vendoring and caldav

vendor/golang.org/x/crypto/AUTHORS

@@ -0,0 +1,3 @@
+# This source code refers to The Go Authors for copyright purposes.
+# The master list of authors is in the main Go distribution,
+# visible at https://tip.golang.org/AUTHORS.

vendor/golang.org/x/crypto/CONTRIBUTORS

@@ -0,0 +1,3 @@
+# This source code was written by the Go contributors.
+# The master list of contributors is in the main Go distribution,
+# visible at https://tip.golang.org/CONTRIBUTORS.

vendor/golang.org/x/crypto/LICENSE

@@ -0,0 +1,27 @@
+Copyright (c) 2009 The Go Authors. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+   * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+   * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+   * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

vendor/golang.org/x/crypto/PATENTS

@@ -0,0 +1,22 @@
+Additional IP Rights Grant (Patents)
+
+"This implementation" means the copyrightable works distributed by
+Google as part of the Go project.
+
+Google hereby grants to You a perpetual, worldwide, non-exclusive,
+no-charge, royalty-free, irrevocable (except as stated in this section)
+patent license to make, have made, use, offer to sell, sell, import,
+transfer and otherwise run, modify and propagate the contents of this
+implementation of Go, where such license applies only to those patent
+claims, both currently owned or controlled by Google and acquired in
+the future, licensable by Google that are necessarily infringed by this
+implementation of Go.  This grant does not include claims that would be
+infringed only as a consequence of further modification of this
+implementation.  If you or your agent or exclusive licensee institute or
+order or agree to the institution of patent litigation against any
+entity (including a cross-claim or counterclaim in a lawsuit) alleging
+that this implementation of Go or any code incorporated within this
+implementation of Go constitutes direct or contributory patent
+infringement, or inducement of patent infringement, then any patent
+rights granted to you under this License for this implementation of Go
+shall terminate as of the date such litigation is filed.

vendor/golang.org/x/crypto/bcrypt/base64.go

@@ -0,0 +1,35 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package bcrypt
+
+import "encoding/base64"
+
+const alphabet = "./ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789"
+
+var bcEncoding = base64.NewEncoding(alphabet)
+
+func base64Encode(src []byte) []byte {
+	n := bcEncoding.EncodedLen(len(src))
+	dst := make([]byte, n)
+	bcEncoding.Encode(dst, src)
+	for dst[n-1] == '=' {
+		n--
+	}
+	return dst[:n]
+}
+
+func base64Decode(src []byte) ([]byte, error) {
+	numOfEquals := 4 - (len(src) % 4)
+	for i := 0; i < numOfEquals; i++ {
+		src = append(src, '=')
+	}
+
+	dst := make([]byte, bcEncoding.DecodedLen(len(src)))
+	n, err := bcEncoding.Decode(dst, src)
+	if err != nil {
+		return nil, err
+	}
+	return dst[:n], nil
+}

vendor/golang.org/x/crypto/bcrypt/bcrypt.go

@@ -0,0 +1,295 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package bcrypt implements Provos and Mazières's bcrypt adaptive hashing
+// algorithm. See http://www.usenix.org/event/usenix99/provos/provos.pdf
+package bcrypt // import "golang.org/x/crypto/bcrypt"
+
+// The code is a port of Provos and Mazières's C implementation.
+import (
+	"crypto/rand"
+	"crypto/subtle"
+	"errors"
+	"fmt"
+	"io"
+	"strconv"
+
+	"golang.org/x/crypto/blowfish"
+)
+
+const (
+	MinCost     int = 4  // the minimum allowable cost as passed in to GenerateFromPassword
+	MaxCost     int = 31 // the maximum allowable cost as passed in to GenerateFromPassword
+	DefaultCost int = 10 // the cost that will actually be set if a cost below MinCost is passed into GenerateFromPassword
+)
+
+// The error returned from CompareHashAndPassword when a password and hash do
+// not match.
+var ErrMismatchedHashAndPassword = errors.New("crypto/bcrypt: hashedPassword is not the hash of the given password")
+
+// The error returned from CompareHashAndPassword when a hash is too short to
+// be a bcrypt hash.
+var ErrHashTooShort = errors.New("crypto/bcrypt: hashedSecret too short to be a bcrypted password")
+
+// The error returned from CompareHashAndPassword when a hash was created with
+// a bcrypt algorithm newer than this implementation.
+type HashVersionTooNewError byte
+
+func (hv HashVersionTooNewError) Error() string {
+	return fmt.Sprintf("crypto/bcrypt: bcrypt algorithm version '%c' requested is newer than current version '%c'", byte(hv), majorVersion)
+}
+
+// The error returned from CompareHashAndPassword when a hash starts with something other than '$'
+type InvalidHashPrefixError byte
+
+func (ih InvalidHashPrefixError) Error() string {
+	return fmt.Sprintf("crypto/bcrypt: bcrypt hashes must start with '$', but hashedSecret started with '%c'", byte(ih))
+}
+
+type InvalidCostError int
+
+func (ic InvalidCostError) Error() string {
+	return fmt.Sprintf("crypto/bcrypt: cost %d is outside allowed range (%d,%d)", int(ic), int(MinCost), int(MaxCost))
+}
+
+const (
+	majorVersion       = '2'
+	minorVersion       = 'a'
+	maxSaltSize        = 16
+	maxCryptedHashSize = 23
+	encodedSaltSize    = 22
+	encodedHashSize    = 31
+	minHashSize        = 59
+)
+
+// magicCipherData is an IV for the 64 Blowfish encryption calls in
+// bcrypt(). It's the string "OrpheanBeholderScryDoubt" in big-endian bytes.
+var magicCipherData = []byte{
+	0x4f, 0x72, 0x70, 0x68,
+	0x65, 0x61, 0x6e, 0x42,
+	0x65, 0x68, 0x6f, 0x6c,
+	0x64, 0x65, 0x72, 0x53,
+	0x63, 0x72, 0x79, 0x44,
+	0x6f, 0x75, 0x62, 0x74,
+}
+
+type hashed struct {
+	hash  []byte
+	salt  []byte
+	cost  int // allowed range is MinCost to MaxCost
+	major byte
+	minor byte
+}
+
+// GenerateFromPassword returns the bcrypt hash of the password at the given
+// cost. If the cost given is less than MinCost, the cost will be set to
+// DefaultCost, instead. Use CompareHashAndPassword, as defined in this package,
+// to compare the returned hashed password with its cleartext version.
+func GenerateFromPassword(password []byte, cost int) ([]byte, error) {
+	p, err := newFromPassword(password, cost)
+	if err != nil {
+		return nil, err
+	}
+	return p.Hash(), nil
+}
+
+// CompareHashAndPassword compares a bcrypt hashed password with its possible
+// plaintext equivalent. Returns nil on success, or an error on failure.
+func CompareHashAndPassword(hashedPassword, password []byte) error {
+	p, err := newFromHash(hashedPassword)
+	if err != nil {
+		return err
+	}
+
+	otherHash, err := bcrypt(password, p.cost, p.salt)
+	if err != nil {
+		return err
+	}
+
+	otherP := &hashed{otherHash, p.salt, p.cost, p.major, p.minor}
+	if subtle.ConstantTimeCompare(p.Hash(), otherP.Hash()) == 1 {
+		return nil
+	}
+
+	return ErrMismatchedHashAndPassword
+}
+
+// Cost returns the hashing cost used to create the given hashed
+// password. When, in the future, the hashing cost of a password system needs
+// to be increased in order to adjust for greater computational power, this
+// function allows one to establish which passwords need to be updated.
+func Cost(hashedPassword []byte) (int, error) {
+	p, err := newFromHash(hashedPassword)
+	if err != nil {
+		return 0, err
+	}
+	return p.cost, nil
+}
+
+func newFromPassword(password []byte, cost int) (*hashed, error) {
+	if cost < MinCost {
+		cost = DefaultCost
+	}
+	p := new(hashed)
+	p.major = majorVersion
+	p.minor = minorVersion
+
+	err := checkCost(cost)
+	if err != nil {
+		return nil, err
+	}
+	p.cost = cost
+
+	unencodedSalt := make([]byte, maxSaltSize)
+	_, err = io.ReadFull(rand.Reader, unencodedSalt)
+	if err != nil {
+		return nil, err
+	}
+
+	p.salt = base64Encode(unencodedSalt)
+	hash, err := bcrypt(password, p.cost, p.salt)
+	if err != nil {
+		return nil, err
+	}
+	p.hash = hash
+	return p, err
+}
+
+func newFromHash(hashedSecret []byte) (*hashed, error) {
+	if len(hashedSecret) < minHashSize {
+		return nil, ErrHashTooShort
+	}
+	p := new(hashed)
+	n, err := p.decodeVersion(hashedSecret)
+	if err != nil {
+		return nil, err
+	}
+	hashedSecret = hashedSecret[n:]
+	n, err = p.decodeCost(hashedSecret)
+	if err != nil {
+		return nil, err
+	}
+	hashedSecret = hashedSecret[n:]
+
+	// The "+2" is here because we'll have to append at most 2 '=' to the salt
+	// when base64 decoding it in expensiveBlowfishSetup().
+	p.salt = make([]byte, encodedSaltSize, encodedSaltSize+2)
+	copy(p.salt, hashedSecret[:encodedSaltSize])
+
+	hashedSecret = hashedSecret[encodedSaltSize:]
+	p.hash = make([]byte, len(hashedSecret))
+	copy(p.hash, hashedSecret)
+
+	return p, nil
+}
+
+func bcrypt(password []byte, cost int, salt []byte) ([]byte, error) {
+	cipherData := make([]byte, len(magicCipherData))
+	copy(cipherData, magicCipherData)
+
+	c, err := expensiveBlowfishSetup(password, uint32(cost), salt)
+	if err != nil {
+		return nil, err
+	}
+
+	for i := 0; i < 24; i += 8 {
+		for j := 0; j < 64; j++ {
+			c.Encrypt(cipherData[i:i+8], cipherData[i:i+8])
+		}
+	}
+
+	// Bug compatibility with C bcrypt implementations. We only encode 23 of
+	// the 24 bytes encrypted.
+	hsh := base64Encode(cipherData[:maxCryptedHashSize])
+	return hsh, nil
+}
+
+func expensiveBlowfishSetup(key []byte, cost uint32, salt []byte) (*blowfish.Cipher, error) {
+	csalt, err := base64Decode(salt)
+	if err != nil {
+		return nil, err
+	}
+
+	// Bug compatibility with C bcrypt implementations. They use the trailing
+	// NULL in the key string during expansion.
+	// We copy the key to prevent changing the underlying array.
+	ckey := append(key[:len(key):len(key)], 0)
+
+	c, err := blowfish.NewSaltedCipher(ckey, csalt)
+	if err != nil {
+		return nil, err
+	}
+
+	var i, rounds uint64
+	rounds = 1 << cost
+	for i = 0; i < rounds; i++ {
+		blowfish.ExpandKey(ckey, c)
+		blowfish.ExpandKey(csalt, c)
+	}
+
+	return c, nil
+}
+
+func (p *hashed) Hash() []byte {
+	arr := make([]byte, 60)
+	arr[0] = '$'
+	arr[1] = p.major
+	n := 2
+	if p.minor != 0 {
+		arr[2] = p.minor
+		n = 3
+	}
+	arr[n] = '$'
+	n++
+	copy(arr[n:], []byte(fmt.Sprintf("%02d", p.cost)))
+	n += 2
+	arr[n] = '$'
+	n++
+	copy(arr[n:], p.salt)
+	n += encodedSaltSize
+	copy(arr[n:], p.hash)
+	n += encodedHashSize
+	return arr[:n]
+}
+
+func (p *hashed) decodeVersion(sbytes []byte) (int, error) {
+	if sbytes[0] != '$' {
+		return -1, InvalidHashPrefixError(sbytes[0])
+	}
+	if sbytes[1] > majorVersion {
+		return -1, HashVersionTooNewError(sbytes[1])
+	}
+	p.major = sbytes[1]
+	n := 3
+	if sbytes[2] != '$' {
+		p.minor = sbytes[2]
+		n++
+	}
+	return n, nil
+}
+
+// sbytes should begin where decodeVersion left off.
+func (p *hashed) decodeCost(sbytes []byte) (int, error) {
+	cost, err := strconv.Atoi(string(sbytes[0:2]))
+	if err != nil {
+		return -1, err
+	}
+	err = checkCost(cost)
+	if err != nil {
+		return -1, err
+	}
+	p.cost = cost
+	return 3, nil
+}
+
+func (p *hashed) String() string {
+	return fmt.Sprintf("&{hash: %#v, salt: %#v, cost: %d, major: %c, minor: %c}", string(p.hash), p.salt, p.cost, p.major, p.minor)
+}
+
+func checkCost(cost int) error {
+	if cost < MinCost || cost > MaxCost {
+		return InvalidCostError(cost)
+	}
+	return nil
+}

vendor/golang.org/x/crypto/blowfish/block.go

@@ -0,0 +1,159 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package blowfish
+
+// getNextWord returns the next big-endian uint32 value from the byte slice
+// at the given position in a circular manner, updating the position.
+func getNextWord(b []byte, pos *int) uint32 {
+	var w uint32
+	j := *pos
+	for i := 0; i < 4; i++ {
+		w = w<<8 | uint32(b[j])
+		j++
+		if j >= len(b) {
+			j = 0
+		}
+	}
+	*pos = j
+	return w
+}
+
+// ExpandKey performs a key expansion on the given *Cipher. Specifically, it
+// performs the Blowfish algorithm's key schedule which sets up the *Cipher's
+// pi and substitution tables for calls to Encrypt. This is used, primarily,
+// by the bcrypt package to reuse the Blowfish key schedule during its
+// set up. It's unlikely that you need to use this directly.
+func ExpandKey(key []byte, c *Cipher) {
+	j := 0
+	for i := 0; i < 18; i++ {
+		// Using inlined getNextWord for performance.
+		var d uint32
+		for k := 0; k < 4; k++ {
+			d = d<<8 | uint32(key[j])
+			j++
+			if j >= len(key) {
+				j = 0
+			}
+		}
+		c.p[i] ^= d
+	}
+
+	var l, r uint32
+	for i := 0; i < 18; i += 2 {
+		l, r = encryptBlock(l, r, c)
+		c.p[i], c.p[i+1] = l, r
+	}
+
+	for i := 0; i < 256; i += 2 {
+		l, r = encryptBlock(l, r, c)
+		c.s0[i], c.s0[i+1] = l, r
+	}
+	for i := 0; i < 256; i += 2 {
+		l, r = encryptBlock(l, r, c)
+		c.s1[i], c.s1[i+1] = l, r
+	}
+	for i := 0; i < 256; i += 2 {
+		l, r = encryptBlock(l, r, c)
+		c.s2[i], c.s2[i+1] = l, r
+	}
+	for i := 0; i < 256; i += 2 {
+		l, r = encryptBlock(l, r, c)
+		c.s3[i], c.s3[i+1] = l, r
+	}
+}
+
+// This is similar to ExpandKey, but folds the salt during the key
+// schedule. While ExpandKey is essentially expandKeyWithSalt with an all-zero
+// salt passed in, reusing ExpandKey turns out to be a place of inefficiency
+// and specializing it here is useful.
+func expandKeyWithSalt(key []byte, salt []byte, c *Cipher) {
+	j := 0
+	for i := 0; i < 18; i++ {
+		c.p[i] ^= getNextWord(key, &j)
+	}
+
+	j = 0
+	var l, r uint32
+	for i := 0; i < 18; i += 2 {
+		l ^= getNextWord(salt, &j)
+		r ^= getNextWord(salt, &j)
+		l, r = encryptBlock(l, r, c)
+		c.p[i], c.p[i+1] = l, r
+	}
+
+	for i := 0; i < 256; i += 2 {
+		l ^= getNextWord(salt, &j)
+		r ^= getNextWord(salt, &j)
+		l, r = encryptBlock(l, r, c)
+		c.s0[i], c.s0[i+1] = l, r
+	}
+
+	for i := 0; i < 256; i += 2 {
+		l ^= getNextWord(salt, &j)
+		r ^= getNextWord(salt, &j)
+		l, r = encryptBlock(l, r, c)
+		c.s1[i], c.s1[i+1] = l, r
+	}
+
+	for i := 0; i < 256; i += 2 {
+		l ^= getNextWord(salt, &j)
+		r ^= getNextWord(salt, &j)
+		l, r = encryptBlock(l, r, c)
+		c.s2[i], c.s2[i+1] = l, r
+	}
+
+	for i := 0; i < 256; i += 2 {
+		l ^= getNextWord(salt, &j)
+		r ^= getNextWord(salt, &j)
+		l, r = encryptBlock(l, r, c)
+		c.s3[i], c.s3[i+1] = l, r
+	}
+}
+
+func encryptBlock(l, r uint32, c *Cipher) (uint32, uint32) {
+	xl, xr := l, r
+	xl ^= c.p[0]
+	xr ^= ((c.s0[byte(xl>>24)] + c.s1[byte(xl>>16)]) ^ c.s2[byte(xl>>8)]) + c.s3[byte(xl)] ^ c.p[1]
+	xl ^= ((c.s0[byte(xr>>24)] + c.s1[byte(xr>>16)]) ^ c.s2[byte(xr>>8)]) + c.s3[byte(xr)] ^ c.p[2]
+	xr ^= ((c.s0[byte(xl>>24)] + c.s1[byte(xl>>16)]) ^ c.s2[byte(xl>>8)]) + c.s3[byte(xl)] ^ c.p[3]
+	xl ^= ((c.s0[byte(xr>>24)] + c.s1[byte(xr>>16)]) ^ c.s2[byte(xr>>8)]) + c.s3[byte(xr)] ^ c.p[4]
+	xr ^= ((c.s0[byte(xl>>24)] + c.s1[byte(xl>>16)]) ^ c.s2[byte(xl>>8)]) + c.s3[byte(xl)] ^ c.p[5]
+	xl ^= ((c.s0[byte(xr>>24)] + c.s1[byte(xr>>16)]) ^ c.s2[byte(xr>>8)]) + c.s3[byte(xr)] ^ c.p[6]
+	xr ^= ((c.s0[byte(xl>>24)] + c.s1[byte(xl>>16)]) ^ c.s2[byte(xl>>8)]) + c.s3[byte(xl)] ^ c.p[7]
+	xl ^= ((c.s0[byte(xr>>24)] + c.s1[byte(xr>>16)]) ^ c.s2[byte(xr>>8)]) + c.s3[byte(xr)] ^ c.p[8]
+	xr ^= ((c.s0[byte(xl>>24)] + c.s1[byte(xl>>16)]) ^ c.s2[byte(xl>>8)]) + c.s3[byte(xl)] ^ c.p[9]
+	xl ^= ((c.s0[byte(xr>>24)] + c.s1[byte(xr>>16)]) ^ c.s2[byte(xr>>8)]) + c.s3[byte(xr)] ^ c.p[10]
+	xr ^= ((c.s0[byte(xl>>24)] + c.s1[byte(xl>>16)]) ^ c.s2[byte(xl>>8)]) + c.s3[byte(xl)] ^ c.p[11]
+	xl ^= ((c.s0[byte(xr>>24)] + c.s1[byte(xr>>16)]) ^ c.s2[byte(xr>>8)]) + c.s3[byte(xr)] ^ c.p[12]
+	xr ^= ((c.s0[byte(xl>>24)] + c.s1[byte(xl>>16)]) ^ c.s2[byte(xl>>8)]) + c.s3[byte(xl)] ^ c.p[13]
+	xl ^= ((c.s0[byte(xr>>24)] + c.s1[byte(xr>>16)]) ^ c.s2[byte(xr>>8)]) + c.s3[byte(xr)] ^ c.p[14]
+	xr ^= ((c.s0[byte(xl>>24)] + c.s1[byte(xl>>16)]) ^ c.s2[byte(xl>>8)]) + c.s3[byte(xl)] ^ c.p[15]
+	xl ^= ((c.s0[byte(xr>>24)] + c.s1[byte(xr>>16)]) ^ c.s2[byte(xr>>8)]) + c.s3[byte(xr)] ^ c.p[16]
+	xr ^= c.p[17]
+	return xr, xl
+}
+
+func decryptBlock(l, r uint32, c *Cipher) (uint32, uint32) {
+	xl, xr := l, r
+	xl ^= c.p[17]
+	xr ^= ((c.s0[byte(xl>>24)] + c.s1[byte(xl>>16)]) ^ c.s2[byte(xl>>8)]) + c.s3[byte(xl)] ^ c.p[16]
+	xl ^= ((c.s0[byte(xr>>24)] + c.s1[byte(xr>>16)]) ^ c.s2[byte(xr>>8)]) + c.s3[byte(xr)] ^ c.p[15]
+	xr ^= ((c.s0[byte(xl>>24)] + c.s1[byte(xl>>16)]) ^ c.s2[byte(xl>>8)]) + c.s3[byte(xl)] ^ c.p[14]
+	xl ^= ((c.s0[byte(xr>>24)] + c.s1[byte(xr>>16)]) ^ c.s2[byte(xr>>8)]) + c.s3[byte(xr)] ^ c.p[13]
+	xr ^= ((c.s0[byte(xl>>24)] + c.s1[byte(xl>>16)]) ^ c.s2[byte(xl>>8)]) + c.s3[byte(xl)] ^ c.p[12]
+	xl ^= ((c.s0[byte(xr>>24)] + c.s1[byte(xr>>16)]) ^ c.s2[byte(xr>>8)]) + c.s3[byte(xr)] ^ c.p[11]
+	xr ^= ((c.s0[byte(xl>>24)] + c.s1[byte(xl>>16)]) ^ c.s2[byte(xl>>8)]) + c.s3[byte(xl)] ^ c.p[10]
+	xl ^= ((c.s0[byte(xr>>24)] + c.s1[byte(xr>>16)]) ^ c.s2[byte(xr>>8)]) + c.s3[byte(xr)] ^ c.p[9]
+	xr ^= ((c.s0[byte(xl>>24)] + c.s1[byte(xl>>16)]) ^ c.s2[byte(xl>>8)]) + c.s3[byte(xl)] ^ c.p[8]
+	xl ^= ((c.s0[byte(xr>>24)] + c.s1[byte(xr>>16)]) ^ c.s2[byte(xr>>8)]) + c.s3[byte(xr)] ^ c.p[7]
+	xr ^= ((c.s0[byte(xl>>24)] + c.s1[byte(xl>>16)]) ^ c.s2[byte(xl>>8)]) + c.s3[byte(xl)] ^ c.p[6]
+	xl ^= ((c.s0[byte(xr>>24)] + c.s1[byte(xr>>16)]) ^ c.s2[byte(xr>>8)]) + c.s3[byte(xr)] ^ c.p[5]
+	xr ^= ((c.s0[byte(xl>>24)] + c.s1[byte(xl>>16)]) ^ c.s2[byte(xl>>8)]) + c.s3[byte(xl)] ^ c.p[4]
+	xl ^= ((c.s0[byte(xr>>24)] + c.s1[byte(xr>>16)]) ^ c.s2[byte(xr>>8)]) + c.s3[byte(xr)] ^ c.p[3]
+	xr ^= ((c.s0[byte(xl>>24)] + c.s1[byte(xl>>16)]) ^ c.s2[byte(xl>>8)]) + c.s3[byte(xl)] ^ c.p[2]
+	xl ^= ((c.s0[byte(xr>>24)] + c.s1[byte(xr>>16)]) ^ c.s2[byte(xr>>8)]) + c.s3[byte(xr)] ^ c.p[1]
+	xr ^= c.p[0]
+	return xr, xl
+}

vendor/golang.org/x/crypto/blowfish/cipher.go

@@ -0,0 +1,91 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package blowfish implements Bruce Schneier's Blowfish encryption algorithm.
+package blowfish // import "golang.org/x/crypto/blowfish"
+
+// The code is a port of Bruce Schneier's C implementation.
+// See https://www.schneier.com/blowfish.html.
+
+import "strconv"
+
+// The Blowfish block size in bytes.
+const BlockSize = 8
+
+// A Cipher is an instance of Blowfish encryption using a particular key.
+type Cipher struct {
+	p              [18]uint32
+	s0, s1, s2, s3 [256]uint32
+}
+
+type KeySizeError int
+
+func (k KeySizeError) Error() string {
+	return "crypto/blowfish: invalid key size " + strconv.Itoa(int(k))
+}
+
+// NewCipher creates and returns a Cipher.
+// The key argument should be the Blowfish key, from 1 to 56 bytes.
+func NewCipher(key []byte) (*Cipher, error) {
+	var result Cipher
+	if k := len(key); k < 1 || k > 56 {
+		return nil, KeySizeError(k)
+	}
+	initCipher(&result)
+	ExpandKey(key, &result)
+	return &result, nil
+}
+
+// NewSaltedCipher creates a returns a Cipher that folds a salt into its key
+// schedule. For most purposes, NewCipher, instead of NewSaltedCipher, is
+// sufficient and desirable. For bcrypt compatibility, the key can be over 56
+// bytes.
+func NewSaltedCipher(key, salt []byte) (*Cipher, error) {
+	if len(salt) == 0 {
+		return NewCipher(key)
+	}
+	var result Cipher
+	if k := len(key); k < 1 {
+		return nil, KeySizeError(k)
+	}
+	initCipher(&result)
+	expandKeyWithSalt(key, salt, &result)
+	return &result, nil
+}
+
+// BlockSize returns the Blowfish block size, 8 bytes.
+// It is necessary to satisfy the Block interface in the
+// package "crypto/cipher".
+func (c *Cipher) BlockSize() int { return BlockSize }
+
+// Encrypt encrypts the 8-byte buffer src using the key k
+// and stores the result in dst.
+// Note that for amounts of data larger than a block,
+// it is not safe to just call Encrypt on successive blocks;
+// instead, use an encryption mode like CBC (see crypto/cipher/cbc.go).
+func (c *Cipher) Encrypt(dst, src []byte) {
+	l := uint32(src[0])<<24 | uint32(src[1])<<16 | uint32(src[2])<<8 | uint32(src[3])
+	r := uint32(src[4])<<24 | uint32(src[5])<<16 | uint32(src[6])<<8 | uint32(src[7])
+	l, r = encryptBlock(l, r, c)
+	dst[0], dst[1], dst[2], dst[3] = byte(l>>24), byte(l>>16), byte(l>>8), byte(l)
+	dst[4], dst[5], dst[6], dst[7] = byte(r>>24), byte(r>>16), byte(r>>8), byte(r)
+}
+
+// Decrypt decrypts the 8-byte buffer src using the key k
+// and stores the result in dst.
+func (c *Cipher) Decrypt(dst, src []byte) {
+	l := uint32(src[0])<<24 | uint32(src[1])<<16 | uint32(src[2])<<8 | uint32(src[3])
+	r := uint32(src[4])<<24 | uint32(src[5])<<16 | uint32(src[6])<<8 | uint32(src[7])
+	l, r = decryptBlock(l, r, c)
+	dst[0], dst[1], dst[2], dst[3] = byte(l>>24), byte(l>>16), byte(l>>8), byte(l)
+	dst[4], dst[5], dst[6], dst[7] = byte(r>>24), byte(r>>16), byte(r>>8), byte(r)
+}
+
+func initCipher(c *Cipher) {
+	copy(c.p[0:], p[0:])
+	copy(c.s0[0:], s0[0:])
+	copy(c.s1[0:], s1[0:])
+	copy(c.s2[0:], s2[0:])
+	copy(c.s3[0:], s3[0:])
+}

vendor/golang.org/x/crypto/blowfish/const.go

@@ -0,0 +1,199 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// The startup permutation array and substitution boxes.
+// They are the hexadecimal digits of PI; see:
+// https://www.schneier.com/code/constants.txt.
+
+package blowfish
+
+var s0 = [256]uint32{
+	0xd1310ba6, 0x98dfb5ac, 0x2ffd72db, 0xd01adfb7, 0xb8e1afed, 0x6a267e96,
+	0xba7c9045, 0xf12c7f99, 0x24a19947, 0xb3916cf7, 0x0801f2e2, 0x858efc16,
+	0x636920d8, 0x71574e69, 0xa458fea3, 0xf4933d7e, 0x0d95748f, 0x728eb658,
+	0x718bcd58, 0x82154aee, 0x7b54a41d, 0xc25a59b5, 0x9c30d539, 0x2af26013,
+	0xc5d1b023, 0x286085f0, 0xca417918, 0xb8db38ef, 0x8e79dcb0, 0x603a180e,
+	0x6c9e0e8b, 0xb01e8a3e, 0xd71577c1, 0xbd314b27, 0x78af2fda, 0x55605c60,
+	0xe65525f3, 0xaa55ab94, 0x57489862, 0x63e81440, 0x55ca396a, 0x2aab10b6,
+	0xb4cc5c34, 0x1141e8ce, 0xa15486af, 0x7c72e993, 0xb3ee1411, 0x636fbc2a,
+	0x2ba9c55d, 0x741831f6, 0xce5c3e16, 0x9b87931e, 0xafd6ba33, 0x6c24cf5c,
+	0x7a325381, 0x28958677, 0x3b8f4898, 0x6b4bb9af, 0xc4bfe81b, 0x66282193,
+	0x61d809cc, 0xfb21a991, 0x487cac60, 0x5dec8032, 0xef845d5d, 0xe98575b1,
+	0xdc262302, 0xeb651b88, 0x23893e81, 0xd396acc5, 0x0f6d6ff3, 0x83f44239,
+	0x2e0b4482, 0xa4842004, 0x69c8f04a, 0x9e1f9b5e, 0x21c66842, 0xf6e96c9a,
+	0x670c9c61, 0xabd388f0, 0x6a51a0d2, 0xd8542f68, 0x960fa728, 0xab5133a3,
+	0x6eef0b6c, 0x137a3be4, 0xba3bf050, 0x7efb2a98, 0xa1f1651d, 0x39af0176,
+	0x66ca593e, 0x82430e88, 0x8cee8619, 0x456f9fb4, 0x7d84a5c3, 0x3b8b5ebe,
+	0xe06f75d8, 0x85c12073, 0x401a449f, 0x56c16aa6, 0x4ed3aa62, 0x363f7706,
+	0x1bfedf72, 0x429b023d, 0x37d0d724, 0xd00a1248, 0xdb0fead3, 0x49f1c09b,
+	0x075372c9, 0x80991b7b, 0x25d479d8, 0xf6e8def7, 0xe3fe501a, 0xb6794c3b,
+	0x976ce0bd, 0x04c006ba, 0xc1a94fb6, 0x409f60c4, 0x5e5c9ec2, 0x196a2463,
+	0x68fb6faf, 0x3e6c53b5, 0x1339b2eb, 0x3b52ec6f, 0x6dfc511f, 0x9b30952c,
+	0xcc814544, 0xaf5ebd09, 0xbee3d004, 0xde334afd, 0x660f2807, 0x192e4bb3,
+	0xc0cba857, 0x45c8740f, 0xd20b5f39, 0xb9d3fbdb, 0x5579c0bd, 0x1a60320a,
+	0xd6a100c6, 0x402c7279, 0x679f25fe, 0xfb1fa3cc, 0x8ea5e9f8, 0xdb3222f8,
+	0x3c7516df, 0xfd616b15, 0x2f501ec8, 0xad0552ab, 0x323db5fa, 0xfd238760,
+	0x53317b48, 0x3e00df82, 0x9e5c57bb, 0xca6f8ca0, 0x1a87562e, 0xdf1769db,
+	0xd542a8f6, 0x287effc3, 0xac6732c6, 0x8c4f5573, 0x695b27b0, 0xbbca58c8,
+	0xe1ffa35d, 0xb8f011a0, 0x10fa3d98, 0xfd2183b8, 0x4afcb56c, 0x2dd1d35b,
+	0x9a53e479, 0xb6f84565, 0xd28e49bc, 0x4bfb9790, 0xe1ddf2da, 0xa4cb7e33,
+	0x62fb1341, 0xcee4c6e8, 0xef20cada, 0x36774c01, 0xd07e9efe, 0x2bf11fb4,
+	0x95dbda4d, 0xae909198, 0xeaad8e71, 0x6b93d5a0, 0xd08ed1d0, 0xafc725e0,
+	0x8e3c5b2f, 0x8e7594b7, 0x8ff6e2fb, 0xf2122b64, 0x8888b812, 0x900df01c,
+	0x4fad5ea0, 0x688fc31c, 0xd1cff191, 0xb3a8c1ad, 0x2f2f2218, 0xbe0e1777,
+	0xea752dfe, 0x8b021fa1, 0xe5a0cc0f, 0xb56f74e8, 0x18acf3d6, 0xce89e299,
+	0xb4a84fe0, 0xfd13e0b7, 0x7cc43b81, 0xd2ada8d9, 0x165fa266, 0x80957705,
+	0x93cc7314, 0x211a1477, 0xe6ad2065, 0x77b5fa86, 0xc75442f5, 0xfb9d35cf,
+	0xebcdaf0c, 0x7b3e89a0, 0xd6411bd3, 0xae1e7e49, 0x00250e2d, 0x2071b35e,
+	0x226800bb, 0x57b8e0af, 0x2464369b, 0xf009b91e, 0x5563911d, 0x59dfa6aa,
+	0x78c14389, 0xd95a537f, 0x207d5ba2, 0x02e5b9c5, 0x83260376, 0x6295cfa9,
+	0x11c81968, 0x4e734a41, 0xb3472dca, 0x7b14a94a, 0x1b510052, 0x9a532915,
+	0xd60f573f, 0xbc9bc6e4, 0x2b60a476, 0x81e67400, 0x08ba6fb5, 0x571be91f,
+	0xf296ec6b, 0x2a0dd915, 0xb6636521, 0xe7b9f9b6, 0xff34052e, 0xc5855664,
+	0x53b02d5d, 0xa99f8fa1, 0x08ba4799, 0x6e85076a,
+}
+
+var s1 = [256]uint32{
+	0x4b7a70e9, 0xb5b32944, 0xdb75092e, 0xc4192623, 0xad6ea6b0, 0x49a7df7d,
+	0x9cee60b8, 0x8fedb266, 0xecaa8c71, 0x699a17ff, 0x5664526c, 0xc2b19ee1,
+	0x193602a5, 0x75094c29, 0xa0591340, 0xe4183a3e, 0x3f54989a, 0x5b429d65,
+	0x6b8fe4d6, 0x99f73fd6, 0xa1d29c07, 0xefe830f5, 0x4d2d38e6, 0xf0255dc1,
+	0x4cdd2086, 0x8470eb26, 0x6382e9c6, 0x021ecc5e, 0x09686b3f, 0x3ebaefc9,
+	0x3c971814, 0x6b6a70a1, 0x687f3584, 0x52a0e286, 0xb79c5305, 0xaa500737,
+	0x3e07841c, 0x7fdeae5c, 0x8e7d44ec, 0x5716f2b8, 0xb03ada37, 0xf0500c0d,
+	0xf01c1f04, 0x0200b3ff, 0xae0cf51a, 0x3cb574b2, 0x25837a58, 0xdc0921bd,
+	0xd19113f9, 0x7ca92ff6, 0x94324773, 0x22f54701, 0x3ae5e581, 0x37c2dadc,
+	0xc8b57634, 0x9af3dda7, 0xa9446146, 0x0fd0030e, 0xecc8c73e, 0xa4751e41,
+	0xe238cd99, 0x3bea0e2f, 0x3280bba1, 0x183eb331, 0x4e548b38, 0x4f6db908,
+	0x6f420d03, 0xf60a04bf, 0x2cb81290, 0x24977c79, 0x5679b072, 0xbcaf89af,
+	0xde9a771f, 0xd9930810, 0xb38bae12, 0xdccf3f2e, 0x5512721f, 0x2e6b7124,
+	0x501adde6, 0x9f84cd87, 0x7a584718, 0x7408da17, 0xbc9f9abc, 0xe94b7d8c,
+	0xec7aec3a, 0xdb851dfa, 0x63094366, 0xc464c3d2, 0xef1c1847, 0x3215d908,
+	0xdd433b37, 0x24c2ba16, 0x12a14d43, 0x2a65c451, 0x50940002, 0x133ae4dd,
+	0x71dff89e, 0x10314e55, 0x81ac77d6, 0x5f11199b, 0x043556f1, 0xd7a3c76b,
+	0x3c11183b, 0x5924a509, 0xf28fe6ed, 0x97f1fbfa, 0x9ebabf2c, 0x1e153c6e,
+	0x86e34570, 0xeae96fb1, 0x860e5e0a, 0x5a3e2ab3, 0x771fe71c, 0x4e3d06fa,
+	0x2965dcb9, 0x99e71d0f, 0x803e89d6, 0x5266c825, 0x2e4cc978, 0x9c10b36a,
+	0xc6150eba, 0x94e2ea78, 0xa5fc3c53, 0x1e0a2df4, 0xf2f74ea7, 0x361d2b3d,
+	0x1939260f, 0x19c27960, 0x5223a708, 0xf71312b6, 0xebadfe6e, 0xeac31f66,
+	0xe3bc4595, 0xa67bc883, 0xb17f37d1, 0x018cff28, 0xc332ddef, 0xbe6c5aa5,
+	0x65582185, 0x68ab9802, 0xeecea50f, 0xdb2f953b, 0x2aef7dad, 0x5b6e2f84,
+	0x1521b628, 0x29076170, 0xecdd4775, 0x619f1510, 0x13cca830, 0xeb61bd96,
+	0x0334fe1e, 0xaa0363cf, 0xb5735c90, 0x4c70a239, 0xd59e9e0b, 0xcbaade14,
+	0xeecc86bc, 0x60622ca7, 0x9cab5cab, 0xb2f3846e, 0x648b1eaf, 0x19bdf0ca,
+	0xa02369b9, 0x655abb50, 0x40685a32, 0x3c2ab4b3, 0x319ee9d5, 0xc021b8f7,
+	0x9b540b19, 0x875fa099, 0x95f7997e, 0x623d7da8, 0xf837889a, 0x97e32d77,
+	0x11ed935f, 0x16681281, 0x0e358829, 0xc7e61fd6, 0x96dedfa1, 0x7858ba99,
+	0x57f584a5, 0x1b227263, 0x9b83c3ff, 0x1ac24696, 0xcdb30aeb, 0x532e3054,
+	0x8fd948e4, 0x6dbc3128, 0x58ebf2ef, 0x34c6ffea, 0xfe28ed61, 0xee7c3c73,
+	0x5d4a14d9, 0xe864b7e3, 0x42105d14, 0x203e13e0, 0x45eee2b6, 0xa3aaabea,
+	0xdb6c4f15, 0xfacb4fd0, 0xc742f442, 0xef6abbb5, 0x654f3b1d, 0x41cd2105,
+	0xd81e799e, 0x86854dc7, 0xe44b476a, 0x3d816250, 0xcf62a1f2, 0x5b8d2646,
+	0xfc8883a0, 0xc1c7b6a3, 0x7f1524c3, 0x69cb7492, 0x47848a0b, 0x5692b285,
+	0x095bbf00, 0xad19489d, 0x1462b174, 0x23820e00, 0x58428d2a, 0x0c55f5ea,
+	0x1dadf43e, 0x233f7061, 0x3372f092, 0x8d937e41, 0xd65fecf1, 0x6c223bdb,
+	0x7cde3759, 0xcbee7460, 0x4085f2a7, 0xce77326e, 0xa6078084, 0x19f8509e,
+	0xe8efd855, 0x61d99735, 0xa969a7aa, 0xc50c06c2, 0x5a04abfc, 0x800bcadc,
+	0x9e447a2e, 0xc3453484, 0xfdd56705, 0x0e1e9ec9, 0xdb73dbd3, 0x105588cd,
+	0x675fda79, 0xe3674340, 0xc5c43465, 0x713e38d8, 0x3d28f89e, 0xf16dff20,
+	0x153e21e7, 0x8fb03d4a, 0xe6e39f2b, 0xdb83adf7,
+}
+
+var s2 = [256]uint32{
+	0xe93d5a68, 0x948140f7, 0xf64c261c, 0x94692934, 0x411520f7, 0x7602d4f7,
+	0xbcf46b2e, 0xd4a20068, 0xd4082471, 0x3320f46a, 0x43b7d4b7, 0x500061af,
+	0x1e39f62e, 0x97244546, 0x14214f74, 0xbf8b8840, 0x4d95fc1d, 0x96b591af,
+	0x70f4ddd3, 0x66a02f45, 0xbfbc09ec, 0x03bd9785, 0x7fac6dd0, 0x31cb8504,
+	0x96eb27b3, 0x55fd3941, 0xda2547e6, 0xabca0a9a, 0x28507825, 0x530429f4,
+	0x0a2c86da, 0xe9b66dfb, 0x68dc1462, 0xd7486900, 0x680ec0a4, 0x27a18dee,
+	0x4f3ffea2, 0xe887ad8c, 0xb58ce006, 0x7af4d6b6, 0xaace1e7c, 0xd3375fec,
+	0xce78a399, 0x406b2a42, 0x20fe9e35, 0xd9f385b9, 0xee39d7ab, 0x3b124e8b,
+	0x1dc9faf7, 0x4b6d1856, 0x26a36631, 0xeae397b2, 0x3a6efa74, 0xdd5b4332,
+	0x6841e7f7, 0xca7820fb, 0xfb0af54e, 0xd8feb397, 0x454056ac, 0xba489527,
+	0x55533a3a, 0x20838d87, 0xfe6ba9b7, 0xd096954b, 0x55a867bc, 0xa1159a58,
+	0xcca92963, 0x99e1db33, 0xa62a4a56, 0x3f3125f9, 0x5ef47e1c, 0x9029317c,
+	0xfdf8e802, 0x04272f70, 0x80bb155c, 0x05282ce3, 0x95c11548, 0xe4c66d22,
+	0x48c1133f, 0xc70f86dc, 0x07f9c9ee, 0x41041f0f, 0x404779a4, 0x5d886e17,
+	0x325f51eb, 0xd59bc0d1, 0xf2bcc18f, 0x41113564, 0x257b7834, 0x602a9c60,
+	0xdff8e8a3, 0x1f636c1b, 0x0e12b4c2, 0x02e1329e, 0xaf664fd1, 0xcad18115,
+	0x6b2395e0, 0x333e92e1, 0x3b240b62, 0xeebeb922, 0x85b2a20e, 0xe6ba0d99,
+	0xde720c8c, 0x2da2f728, 0xd0127845, 0x95b794fd, 0x647d0862, 0xe7ccf5f0,
+	0x5449a36f, 0x877d48fa, 0xc39dfd27, 0xf33e8d1e, 0x0a476341, 0x992eff74,
+	0x3a6f6eab, 0xf4f8fd37, 0xa812dc60, 0xa1ebddf8, 0x991be14c, 0xdb6e6b0d,
+	0xc67b5510, 0x6d672c37, 0x2765d43b, 0xdcd0e804, 0xf1290dc7, 0xcc00ffa3,
+	0xb5390f92, 0x690fed0b, 0x667b9ffb, 0xcedb7d9c, 0xa091cf0b, 0xd9155ea3,
+	0xbb132f88, 0x515bad24, 0x7b9479bf, 0x763bd6eb, 0x37392eb3, 0xcc115979,
+	0x8026e297, 0xf42e312d, 0x6842ada7, 0xc66a2b3b, 0x12754ccc, 0x782ef11c,
+	0x6a124237, 0xb79251e7, 0x06a1bbe6, 0x4bfb6350, 0x1a6b1018, 0x11caedfa,
+	0x3d25bdd8, 0xe2e1c3c9, 0x44421659, 0x0a121386, 0xd90cec6e, 0xd5abea2a,
+	0x64af674e, 0xda86a85f, 0xbebfe988, 0x64e4c3fe, 0x9dbc8057, 0xf0f7c086,
+	0x60787bf8, 0x6003604d, 0xd1fd8346, 0xf6381fb0, 0x7745ae04, 0xd736fccc,
+	0x83426b33, 0xf01eab71, 0xb0804187, 0x3c005e5f, 0x77a057be, 0xbde8ae24,
+	0x55464299, 0xbf582e61, 0x4e58f48f, 0xf2ddfda2, 0xf474ef38, 0x8789bdc2,
+	0x5366f9c3, 0xc8b38e74, 0xb475f255, 0x46fcd9b9, 0x7aeb2661, 0x8b1ddf84,
+	0x846a0e79, 0x915f95e2, 0x466e598e, 0x20b45770, 0x8cd55591, 0xc902de4c,
+	0xb90bace1, 0xbb8205d0, 0x11a86248, 0x7574a99e, 0xb77f19b6, 0xe0a9dc09,
+	0x662d09a1, 0xc4324633, 0xe85a1f02, 0x09f0be8c, 0x4a99a025, 0x1d6efe10,
+	0x1ab93d1d, 0x0ba5a4df, 0xa186f20f, 0x2868f169, 0xdcb7da83, 0x573906fe,
+	0xa1e2ce9b, 0x4fcd7f52, 0x50115e01, 0xa70683fa, 0xa002b5c4, 0x0de6d027,
+	0x9af88c27, 0x773f8641, 0xc3604c06, 0x61a806b5, 0xf0177a28, 0xc0f586e0,
+	0x006058aa, 0x30dc7d62, 0x11e69ed7, 0x2338ea63, 0x53c2dd94, 0xc2c21634,
+	0xbbcbee56, 0x90bcb6de, 0xebfc7da1, 0xce591d76, 0x6f05e409, 0x4b7c0188,
+	0x39720a3d, 0x7c927c24, 0x86e3725f, 0x724d9db9, 0x1ac15bb4, 0xd39eb8fc,
+	0xed545578, 0x08fca5b5, 0xd83d7cd3, 0x4dad0fc4, 0x1e50ef5e, 0xb161e6f8,
+	0xa28514d9, 0x6c51133c, 0x6fd5c7e7, 0x56e14ec4, 0x362abfce, 0xddc6c837,
+	0xd79a3234, 0x92638212, 0x670efa8e, 0x406000e0,
+}
+
+var s3 = [256]uint32{
+	0x3a39ce37, 0xd3faf5cf, 0xabc27737, 0x5ac52d1b, 0x5cb0679e, 0x4fa33742,
+	0xd3822740, 0x99bc9bbe, 0xd5118e9d, 0xbf0f7315, 0xd62d1c7e, 0xc700c47b,
+	0xb78c1b6b, 0x21a19045, 0xb26eb1be, 0x6a366eb4, 0x5748ab2f, 0xbc946e79,
+	0xc6a376d2, 0x6549c2c8, 0x530ff8ee, 0x468dde7d, 0xd5730a1d, 0x4cd04dc6,
+	0x2939bbdb, 0xa9ba4650, 0xac9526e8, 0xbe5ee304, 0xa1fad5f0, 0x6a2d519a,
+	0x63ef8ce2, 0x9a86ee22, 0xc089c2b8, 0x43242ef6, 0xa51e03aa, 0x9cf2d0a4,
+	0x83c061ba, 0x9be96a4d, 0x8fe51550, 0xba645bd6, 0x2826a2f9, 0xa73a3ae1,
+	0x4ba99586, 0xef5562e9, 0xc72fefd3, 0xf752f7da, 0x3f046f69, 0x77fa0a59,
+	0x80e4a915, 0x87b08601, 0x9b09e6ad, 0x3b3ee593, 0xe990fd5a, 0x9e34d797,
+	0x2cf0b7d9, 0x022b8b51, 0x96d5ac3a, 0x017da67d, 0xd1cf3ed6, 0x7c7d2d28,
+	0x1f9f25cf, 0xadf2b89b, 0x5ad6b472, 0x5a88f54c, 0xe029ac71, 0xe019a5e6,
+	0x47b0acfd, 0xed93fa9b, 0xe8d3c48d, 0x283b57cc, 0xf8d56629, 0x79132e28,
+	0x785f0191, 0xed756055, 0xf7960e44, 0xe3d35e8c, 0x15056dd4, 0x88f46dba,
+	0x03a16125, 0x0564f0bd, 0xc3eb9e15, 0x3c9057a2, 0x97271aec, 0xa93a072a,
+	0x1b3f6d9b, 0x1e6321f5, 0xf59c66fb, 0x26dcf319, 0x7533d928, 0xb155fdf5,
+	0x03563482, 0x8aba3cbb, 0x28517711, 0xc20ad9f8, 0xabcc5167, 0xccad925f,
+	0x4de81751, 0x3830dc8e, 0x379d5862, 0x9320f991, 0xea7a90c2, 0xfb3e7bce,
+	0x5121ce64, 0x774fbe32, 0xa8b6e37e, 0xc3293d46, 0x48de5369, 0x6413e680,
+	0xa2ae0810, 0xdd6db224, 0x69852dfd, 0x09072166, 0xb39a460a, 0x6445c0dd,
+	0x586cdecf, 0x1c20c8ae, 0x5bbef7dd, 0x1b588d40, 0xccd2017f, 0x6bb4e3bb,
+	0xdda26a7e, 0x3a59ff45, 0x3e350a44, 0xbcb4cdd5, 0x72eacea8, 0xfa6484bb,
+	0x8d6612ae, 0xbf3c6f47, 0xd29be463, 0x542f5d9e, 0xaec2771b, 0xf64e6370,
+	0x740e0d8d, 0xe75b1357, 0xf8721671, 0xaf537d5d, 0x4040cb08, 0x4eb4e2cc,
+	0x34d2466a, 0x0115af84, 0xe1b00428, 0x95983a1d, 0x06b89fb4, 0xce6ea048,
+	0x6f3f3b82, 0x3520ab82, 0x011a1d4b, 0x277227f8, 0x611560b1, 0xe7933fdc,
+	0xbb3a792b, 0x344525bd, 0xa08839e1, 0x51ce794b, 0x2f32c9b7, 0xa01fbac9,
+	0xe01cc87e, 0xbcc7d1f6, 0xcf0111c3, 0xa1e8aac7, 0x1a908749, 0xd44fbd9a,
+	0xd0dadecb, 0xd50ada38, 0x0339c32a, 0xc6913667, 0x8df9317c, 0xe0b12b4f,
+	0xf79e59b7, 0x43f5bb3a, 0xf2d519ff, 0x27d9459c, 0xbf97222c, 0x15e6fc2a,
+	0x0f91fc71, 0x9b941525, 0xfae59361, 0xceb69ceb, 0xc2a86459, 0x12baa8d1,
+	0xb6c1075e, 0xe3056a0c, 0x10d25065, 0xcb03a442, 0xe0ec6e0e, 0x1698db3b,
+	0x4c98a0be, 0x3278e964, 0x9f1f9532, 0xe0d392df, 0xd3a0342b, 0x8971f21e,
+	0x1b0a7441, 0x4ba3348c, 0xc5be7120, 0xc37632d8, 0xdf359f8d, 0x9b992f2e,
+	0xe60b6f47, 0x0fe3f11d, 0xe54cda54, 0x1edad891, 0xce6279cf, 0xcd3e7e6f,
+	0x1618b166, 0xfd2c1d05, 0x848fd2c5, 0xf6fb2299, 0xf523f357, 0xa6327623,
+	0x93a83531, 0x56cccd02, 0xacf08162, 0x5a75ebb5, 0x6e163697, 0x88d273cc,
+	0xde966292, 0x81b949d0, 0x4c50901b, 0x71c65614, 0xe6c6c7bd, 0x327a140a,
+	0x45e1d006, 0xc3f27b9a, 0xc9aa53fd, 0x62a80f00, 0xbb25bfe2, 0x35bdd2f6,
+	0x71126905, 0xb2040222, 0xb6cbcf7c, 0xcd769c2b, 0x53113ec0, 0x1640e3d3,
+	0x38abbd60, 0x2547adf0, 0xba38209c, 0xf746ce76, 0x77afa1c5, 0x20756060,
+	0x85cbfe4e, 0x8ae88dd8, 0x7aaaf9b0, 0x4cf9aa7e, 0x1948c25c, 0x02fb8a8c,
+	0x01c36ae4, 0xd6ebe1f9, 0x90d4f869, 0xa65cdea0, 0x3f09252d, 0xc208e69f,
+	0xb74e6132, 0xce77e25b, 0x578fdfe3, 0x3ac372e6,
+}
+
+var p = [18]uint32{
+	0x243f6a88, 0x85a308d3, 0x13198a2e, 0x03707344, 0xa4093822, 0x299f31d0,
+	0x082efa98, 0xec4e6c89, 0x452821e6, 0x38d01377, 0xbe5466cf, 0x34e90c6c,
+	0xc0ac29b7, 0xc97c50dd, 0x3f84d5b5, 0xb5470917, 0x9216d5d9, 0x8979fb1b,
+}

vendor/golang.org/x/net/AUTHORS

@@ -0,0 +1,3 @@
+# This source code refers to The Go Authors for copyright purposes.
+# The master list of authors is in the main Go distribution,
+# visible at http://tip.golang.org/AUTHORS.

vendor/golang.org/x/net/CONTRIBUTORS

@@ -0,0 +1,3 @@
+# This source code was written by the Go contributors.
+# The master list of contributors is in the main Go distribution,
+# visible at http://tip.golang.org/CONTRIBUTORS.

vendor/golang.org/x/net/LICENSE

@@ -0,0 +1,27 @@
+Copyright (c) 2009 The Go Authors. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+   * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+   * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+   * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

vendor/golang.org/x/net/PATENTS

@@ -0,0 +1,22 @@
+Additional IP Rights Grant (Patents)
+
+"This implementation" means the copyrightable works distributed by
+Google as part of the Go project.
+
+Google hereby grants to You a perpetual, worldwide, non-exclusive,
+no-charge, royalty-free, irrevocable (except as stated in this section)
+patent license to make, have made, use, offer to sell, sell, import,
+transfer and otherwise run, modify and propagate the contents of this
+implementation of Go, where such license applies only to those patent
+claims, both currently owned or controlled by Google and acquired in
+the future, licensable by Google that are necessarily infringed by this
+implementation of Go.  This grant does not include claims that would be
+infringed only as a consequence of further modification of this
+implementation.  If you or your agent or exclusive licensee institute or
+order or agree to the institution of patent litigation against any
+entity (including a cross-claim or counterclaim in a lawsuit) alleging
+that this implementation of Go or any code incorporated within this
+implementation of Go constitutes direct or contributory patent
+infringement, or inducement of patent infringement, then any patent
+rights granted to you under this License for this implementation of Go
+shall terminate as of the date such litigation is filed.

vendor/golang.org/x/net/context/context.go

@@ -0,0 +1,56 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package context defines the Context type, which carries deadlines,
+// cancelation signals, and other request-scoped values across API boundaries
+// and between processes.
+// As of Go 1.7 this package is available in the standard library under the
+// name context.  https://golang.org/pkg/context.
+//
+// Incoming requests to a server should create a Context, and outgoing calls to
+// servers should accept a Context. The chain of function calls between must
+// propagate the Context, optionally replacing it with a modified copy created
+// using WithDeadline, WithTimeout, WithCancel, or WithValue.
+//
+// Programs that use Contexts should follow these rules to keep interfaces
+// consistent across packages and enable static analysis tools to check context
+// propagation:
+//
+// Do not store Contexts inside a struct type; instead, pass a Context
+// explicitly to each function that needs it. The Context should be the first
+// parameter, typically named ctx:
+//
+// 	func DoSomething(ctx context.Context, arg Arg) error {
+// 		// ... use ctx ...
+// 	}
+//
+// Do not pass a nil Context, even if a function permits it. Pass context.TODO
+// if you are unsure about which Context to use.
+//
+// Use context Values only for request-scoped data that transits processes and
+// APIs, not for passing optional parameters to functions.
+//
+// The same Context may be passed to functions running in different goroutines;
+// Contexts are safe for simultaneous use by multiple goroutines.
+//
+// See http://blog.golang.org/context for example code for a server that uses
+// Contexts.
+package context // import "golang.org/x/net/context"
+
+// Background returns a non-nil, empty Context. It is never canceled, has no
+// values, and has no deadline. It is typically used by the main function,
+// initialization, and tests, and as the top-level Context for incoming
+// requests.
+func Background() Context {
+	return background
+}
+
+// TODO returns a non-nil, empty Context. Code should use context.TODO when
+// it's unclear which Context to use or it is not yet available (because the
+// surrounding function has not yet been extended to accept a Context
+// parameter).  TODO is recognized by static analysis tools that determine
+// whether Contexts are propagated correctly in a program.
+func TODO() Context {
+	return todo
+}

vendor/golang.org/x/net/context/go17.go

@@ -0,0 +1,72 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build go1.7
+
+package context
+
+import (
+	"context" // standard library's context, as of Go 1.7
+	"time"
+)
+
+var (
+	todo       = context.TODO()
+	background = context.Background()
+)
+
+// Canceled is the error returned by Context.Err when the context is canceled.
+var Canceled = context.Canceled
+
+// DeadlineExceeded is the error returned by Context.Err when the context's
+// deadline passes.
+var DeadlineExceeded = context.DeadlineExceeded
+
+// WithCancel returns a copy of parent with a new Done channel. The returned
+// context's Done channel is closed when the returned cancel function is called
+// or when the parent context's Done channel is closed, whichever happens first.
+//
+// Canceling this context releases resources associated with it, so code should
+// call cancel as soon as the operations running in this Context complete.
+func WithCancel(parent Context) (ctx Context, cancel CancelFunc) {
+	ctx, f := context.WithCancel(parent)
+	return ctx, CancelFunc(f)
+}
+
+// WithDeadline returns a copy of the parent context with the deadline adjusted
+// to be no later than d. If the parent's deadline is already earlier than d,
+// WithDeadline(parent, d) is semantically equivalent to parent. The returned
+// context's Done channel is closed when the deadline expires, when the returned
+// cancel function is called, or when the parent context's Done channel is
+// closed, whichever happens first.
+//
+// Canceling this context releases resources associated with it, so code should
+// call cancel as soon as the operations running in this Context complete.
+func WithDeadline(parent Context, deadline time.Time) (Context, CancelFunc) {
+	ctx, f := context.WithDeadline(parent, deadline)
+	return ctx, CancelFunc(f)
+}
+
+// WithTimeout returns WithDeadline(parent, time.Now().Add(timeout)).
+//
+// Canceling this context releases resources associated with it, so code should
+// call cancel as soon as the operations running in this Context complete:
+//
+// 	func slowOperationWithTimeout(ctx context.Context) (Result, error) {
+// 		ctx, cancel := context.WithTimeout(ctx, 100*time.Millisecond)
+// 		defer cancel()  // releases resources if slowOperation completes before timeout elapses
+// 		return slowOperation(ctx)
+// 	}
+func WithTimeout(parent Context, timeout time.Duration) (Context, CancelFunc) {
+	return WithDeadline(parent, time.Now().Add(timeout))
+}
+
+// WithValue returns a copy of parent in which the value associated with key is
+// val.
+//
+// Use context Values only for request-scoped data that transits processes and
+// APIs, not for passing optional parameters to functions.
+func WithValue(parent Context, key interface{}, val interface{}) Context {
+	return context.WithValue(parent, key, val)
+}

vendor/golang.org/x/net/context/go19.go

@@ -0,0 +1,20 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build go1.9
+
+package context
+
+import "context" // standard library's context, as of Go 1.7
+
+// A Context carries a deadline, a cancelation signal, and other values across
+// API boundaries.
+//
+// Context's methods may be called by multiple goroutines simultaneously.
+type Context = context.Context
+
+// A CancelFunc tells an operation to abandon its work.
+// A CancelFunc does not wait for the work to stop.
+// After the first call, subsequent calls to a CancelFunc do nothing.
+type CancelFunc = context.CancelFunc

vendor/golang.org/x/net/context/pre_go17.go

@@ -0,0 +1,300 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !go1.7
+
+package context
+
+import (
+	"errors"
+	"fmt"
+	"sync"
+	"time"
+)
+
+// An emptyCtx is never canceled, has no values, and has no deadline. It is not
+// struct{}, since vars of this type must have distinct addresses.
+type emptyCtx int
+
+func (*emptyCtx) Deadline() (deadline time.Time, ok bool) {
+	return
+}
+
+func (*emptyCtx) Done() <-chan struct{} {
+	return nil
+}
+
+func (*emptyCtx) Err() error {
+	return nil
+}
+
+func (*emptyCtx) Value(key interface{}) interface{} {
+	return nil
+}
+
+func (e *emptyCtx) String() string {
+	switch e {
+	case background:
+		return "context.Background"
+	case todo:
+		return "context.TODO"
+	}
+	return "unknown empty Context"
+}
+
+var (
+	background = new(emptyCtx)
+	todo       = new(emptyCtx)
+)
+
+// Canceled is the error returned by Context.Err when the context is canceled.
+var Canceled = errors.New("context canceled")
+
+// DeadlineExceeded is the error returned by Context.Err when the context's
+// deadline passes.
+var DeadlineExceeded = errors.New("context deadline exceeded")
+
+// WithCancel returns a copy of parent with a new Done channel. The returned
+// context's Done channel is closed when the returned cancel function is called
+// or when the parent context's Done channel is closed, whichever happens first.
+//
+// Canceling this context releases resources associated with it, so code should
+// call cancel as soon as the operations running in this Context complete.
+func WithCancel(parent Context) (ctx Context, cancel CancelFunc) {
+	c := newCancelCtx(parent)
+	propagateCancel(parent, c)
+	return c, func() { c.cancel(true, Canceled) }
+}
+
+// newCancelCtx returns an initialized cancelCtx.
+func newCancelCtx(parent Context) *cancelCtx {
+	return &cancelCtx{
+		Context: parent,
+		done:    make(chan struct{}),
+	}
+}
+
+// propagateCancel arranges for child to be canceled when parent is.
+func propagateCancel(parent Context, child canceler) {
+	if parent.Done() == nil {
+		return // parent is never canceled
+	}
+	if p, ok := parentCancelCtx(parent); ok {
+		p.mu.Lock()
+		if p.err != nil {
+			// parent has already been canceled
+			child.cancel(false, p.err)
+		} else {
+			if p.children == nil {
+				p.children = make(map[canceler]bool)
+			}
+			p.children[child] = true
+		}
+		p.mu.Unlock()
+	} else {
+		go func() {
+			select {
+			case <-parent.Done():
+				child.cancel(false, parent.Err())
+			case <-child.Done():
+			}
+		}()
+	}
+}
+
+// parentCancelCtx follows a chain of parent references until it finds a
+// *cancelCtx. This function understands how each of the concrete types in this
+// package represents its parent.
+func parentCancelCtx(parent Context) (*cancelCtx, bool) {
+	for {
+		switch c := parent.(type) {
+		case *cancelCtx:
+			return c, true
+		case *timerCtx:
+			return c.cancelCtx, true
+		case *valueCtx:
+			parent = c.Context
+		default:
+			return nil, false
+		}
+	}
+}
+
+// removeChild removes a context from its parent.
+func removeChild(parent Context, child canceler) {
+	p, ok := parentCancelCtx(parent)
+	if !ok {
+		return
+	}
+	p.mu.Lock()
+	if p.children != nil {
+		delete(p.children, child)
+	}
+	p.mu.Unlock()
+}
+
+// A canceler is a context type that can be canceled directly. The
+// implementations are *cancelCtx and *timerCtx.
+type canceler interface {
+	cancel(removeFromParent bool, err error)
+	Done() <-chan struct{}
+}
+
+// A cancelCtx can be canceled. When canceled, it also cancels any children
+// that implement canceler.
+type cancelCtx struct {
+	Context
+
+	done chan struct{} // closed by the first cancel call.
+
+	mu       sync.Mutex
+	children map[canceler]bool // set to nil by the first cancel call
+	err      error             // set to non-nil by the first cancel call
+}
+
+func (c *cancelCtx) Done() <-chan struct{} {
+	return c.done
+}
+
+func (c *cancelCtx) Err() error {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	return c.err
+}
+
+func (c *cancelCtx) String() string {
+	return fmt.Sprintf("%v.WithCancel", c.Context)
+}
+
+// cancel closes c.done, cancels each of c's children, and, if
+// removeFromParent is true, removes c from its parent's children.
+func (c *cancelCtx) cancel(removeFromParent bool, err error) {
+	if err == nil {
+		panic("context: internal error: missing cancel error")
+	}
+	c.mu.Lock()
+	if c.err != nil {
+		c.mu.Unlock()
+		return // already canceled
+	}
+	c.err = err
+	close(c.done)
+	for child := range c.children {
+		// NOTE: acquiring the child's lock while holding parent's lock.
+		child.cancel(false, err)
+	}
+	c.children = nil
+	c.mu.Unlock()
+
+	if removeFromParent {
+		removeChild(c.Context, c)
+	}
+}
+
+// WithDeadline returns a copy of the parent context with the deadline adjusted
+// to be no later than d. If the parent's deadline is already earlier than d,
+// WithDeadline(parent, d) is semantically equivalent to parent. The returned
+// context's Done channel is closed when the deadline expires, when the returned
+// cancel function is called, or when the parent context's Done channel is
+// closed, whichever happens first.
+//
+// Canceling this context releases resources associated with it, so code should
+// call cancel as soon as the operations running in this Context complete.
+func WithDeadline(parent Context, deadline time.Time) (Context, CancelFunc) {
+	if cur, ok := parent.Deadline(); ok && cur.Before(deadline) {
+		// The current deadline is already sooner than the new one.
+		return WithCancel(parent)
+	}
+	c := &timerCtx{
+		cancelCtx: newCancelCtx(parent),
+		deadline:  deadline,
+	}
+	propagateCancel(parent, c)
+	d := deadline.Sub(time.Now())
+	if d <= 0 {
+		c.cancel(true, DeadlineExceeded) // deadline has already passed
+		return c, func() { c.cancel(true, Canceled) }
+	}
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	if c.err == nil {
+		c.timer = time.AfterFunc(d, func() {
+			c.cancel(true, DeadlineExceeded)
+		})
+	}
+	return c, func() { c.cancel(true, Canceled) }
+}
+
+// A timerCtx carries a timer and a deadline. It embeds a cancelCtx to
+// implement Done and Err. It implements cancel by stopping its timer then
+// delegating to cancelCtx.cancel.
+type timerCtx struct {
+	*cancelCtx
+	timer *time.Timer // Under cancelCtx.mu.
+
+	deadline time.Time
+}
+
+func (c *timerCtx) Deadline() (deadline time.Time, ok bool) {
+	return c.deadline, true
+}
+
+func (c *timerCtx) String() string {
+	return fmt.Sprintf("%v.WithDeadline(%s [%s])", c.cancelCtx.Context, c.deadline, c.deadline.Sub(time.Now()))
+}
+
+func (c *timerCtx) cancel(removeFromParent bool, err error) {
+	c.cancelCtx.cancel(false, err)
+	if removeFromParent {
+		// Remove this timerCtx from its parent cancelCtx's children.
+		removeChild(c.cancelCtx.Context, c)
+	}
+	c.mu.Lock()
+	if c.timer != nil {
+		c.timer.Stop()
+		c.timer = nil
+	}
+	c.mu.Unlock()
+}
+
+// WithTimeout returns WithDeadline(parent, time.Now().Add(timeout)).
+//
+// Canceling this context releases resources associated with it, so code should
+// call cancel as soon as the operations running in this Context complete:
+//
+// 	func slowOperationWithTimeout(ctx context.Context) (Result, error) {
+// 		ctx, cancel := context.WithTimeout(ctx, 100*time.Millisecond)
+// 		defer cancel()  // releases resources if slowOperation completes before timeout elapses
+// 		return slowOperation(ctx)
+// 	}
+func WithTimeout(parent Context, timeout time.Duration) (Context, CancelFunc) {
+	return WithDeadline(parent, time.Now().Add(timeout))
+}
+
+// WithValue returns a copy of parent in which the value associated with key is
+// val.
+//
+// Use context Values only for request-scoped data that transits processes and
+// APIs, not for passing optional parameters to functions.
+func WithValue(parent Context, key interface{}, val interface{}) Context {
+	return &valueCtx{parent, key, val}
+}
+
+// A valueCtx carries a key-value pair. It implements Value for that key and
+// delegates all other calls to the embedded Context.
+type valueCtx struct {
+	Context
+	key, val interface{}
+}
+
+func (c *valueCtx) String() string {
+	return fmt.Sprintf("%v.WithValue(%#v, %#v)", c.Context, c.key, c.val)
+}
+
+func (c *valueCtx) Value(key interface{}) interface{} {
+	if c.key == key {
+		return c.val
+	}
+	return c.Context.Value(key)
+}

vendor/golang.org/x/net/context/pre_go19.go

@@ -0,0 +1,109 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !go1.9
+
+package context
+
+import "time"
+
+// A Context carries a deadline, a cancelation signal, and other values across
+// API boundaries.
+//
+// Context's methods may be called by multiple goroutines simultaneously.
+type Context interface {
+	// Deadline returns the time when work done on behalf of this context
+	// should be canceled. Deadline returns ok==false when no deadline is
+	// set. Successive calls to Deadline return the same results.
+	Deadline() (deadline time.Time, ok bool)
+
+	// Done returns a channel that's closed when work done on behalf of this
+	// context should be canceled. Done may return nil if this context can
+	// never be canceled. Successive calls to Done return the same value.
+	//
+	// WithCancel arranges for Done to be closed when cancel is called;
+	// WithDeadline arranges for Done to be closed when the deadline
+	// expires; WithTimeout arranges for Done to be closed when the timeout
+	// elapses.
+	//
+	// Done is provided for use in select statements:
+	//
+	//  // Stream generates values with DoSomething and sends them to out
+	//  // until DoSomething returns an error or ctx.Done is closed.
+	//  func Stream(ctx context.Context, out chan<- Value) error {
+	//  	for {
+	//  		v, err := DoSomething(ctx)
+	//  		if err != nil {
+	//  			return err
+	//  		}
+	//  		select {
+	//  		case <-ctx.Done():
+	//  			return ctx.Err()
+	//  		case out <- v:
+	//  		}
+	//  	}
+	//  }
+	//
+	// See http://blog.golang.org/pipelines for more examples of how to use
+	// a Done channel for cancelation.
+	Done() <-chan struct{}
+
+	// Err returns a non-nil error value after Done is closed. Err returns
+	// Canceled if the context was canceled or DeadlineExceeded if the
+	// context's deadline passed. No other values for Err are defined.
+	// After Done is closed, successive calls to Err return the same value.
+	Err() error
+
+	// Value returns the value associated with this context for key, or nil
+	// if no value is associated with key. Successive calls to Value with
+	// the same key returns the same result.
+	//
+	// Use context values only for request-scoped data that transits
+	// processes and API boundaries, not for passing optional parameters to
+	// functions.
+	//
+	// A key identifies a specific value in a Context. Functions that wish
+	// to store values in Context typically allocate a key in a global
+	// variable then use that key as the argument to context.WithValue and
+	// Context.Value. A key can be any type that supports equality;
+	// packages should define keys as an unexported type to avoid
+	// collisions.
+	//
+	// Packages that define a Context key should provide type-safe accessors
+	// for the values stores using that key:
+	//
+	// 	// Package user defines a User type that's stored in Contexts.
+	// 	package user
+	//
+	// 	import "golang.org/x/net/context"
+	//
+	// 	// User is the type of value stored in the Contexts.
+	// 	type User struct {...}
+	//
+	// 	// key is an unexported type for keys defined in this package.
+	// 	// This prevents collisions with keys defined in other packages.
+	// 	type key int
+	//
+	// 	// userKey is the key for user.User values in Contexts. It is
+	// 	// unexported; clients use user.NewContext and user.FromContext
+	// 	// instead of using this key directly.
+	// 	var userKey key = 0
+	//
+	// 	// NewContext returns a new Context that carries value u.
+	// 	func NewContext(ctx context.Context, u *User) context.Context {
+	// 		return context.WithValue(ctx, userKey, u)
+	// 	}
+	//
+	// 	// FromContext returns the User value stored in ctx, if any.
+	// 	func FromContext(ctx context.Context) (*User, bool) {
+	// 		u, ok := ctx.Value(userKey).(*User)
+	// 		return u, ok
+	// 	}
+	Value(key interface{}) interface{}
+}
+
+// A CancelFunc tells an operation to abandon its work.
+// A CancelFunc does not wait for the work to stop.
+// After the first call, subsequent calls to a CancelFunc do nothing.
+type CancelFunc func()

vendor/golang.org/x/net/webdav/file.go

@@ -0,0 +1,796 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package webdav
+
+import (
+	"encoding/xml"
+	"io"
+	"net/http"
+	"os"
+	"path"
+	"path/filepath"
+	"strings"
+	"sync"
+	"time"
+
+	"golang.org/x/net/context"
+)
+
+// slashClean is equivalent to but slightly more efficient than
+// path.Clean("/" + name).
+func slashClean(name string) string {
+	if name == "" || name[0] != '/' {
+		name = "/" + name
+	}
+	return path.Clean(name)
+}
+
+// A FileSystem implements access to a collection of named files. The elements
+// in a file path are separated by slash ('/', U+002F) characters, regardless
+// of host operating system convention.
+//
+// Each method has the same semantics as the os package's function of the same
+// name.
+//
+// Note that the os.Rename documentation says that "OS-specific restrictions
+// might apply". In particular, whether or not renaming a file or directory
+// overwriting another existing file or directory is an error is OS-dependent.
+type FileSystem interface {
+	Mkdir(ctx context.Context, name string, perm os.FileMode) error
+	OpenFile(ctx context.Context, name string, flag int, perm os.FileMode) (File, error)
+	RemoveAll(ctx context.Context, name string) error
+	Rename(ctx context.Context, oldName, newName string) error
+	Stat(ctx context.Context, name string) (os.FileInfo, error)
+}
+
+// A File is returned by a FileSystem's OpenFile method and can be served by a
+// Handler.
+//
+// A File may optionally implement the DeadPropsHolder interface, if it can
+// load and save dead properties.
+type File interface {
+	http.File
+	io.Writer
+}
+
+// A Dir implements FileSystem using the native file system restricted to a
+// specific directory tree.
+//
+// While the FileSystem.OpenFile method takes '/'-separated paths, a Dir's
+// string value is a filename on the native file system, not a URL, so it is
+// separated by filepath.Separator, which isn't necessarily '/'.
+//
+// An empty Dir is treated as ".".
+type Dir string
+
+func (d Dir) resolve(name string) string {
+	// This implementation is based on Dir.Open's code in the standard net/http package.
+	if filepath.Separator != '/' && strings.IndexRune(name, filepath.Separator) >= 0 ||
+		strings.Contains(name, "\x00") {
+		return ""
+	}
+	dir := string(d)
+	if dir == "" {
+		dir = "."
+	}
+	return filepath.Join(dir, filepath.FromSlash(slashClean(name)))
+}
+
+func (d Dir) Mkdir(ctx context.Context, name string, perm os.FileMode) error {
+	if name = d.resolve(name); name == "" {
+		return os.ErrNotExist
+	}
+	return os.Mkdir(name, perm)
+}
+
+func (d Dir) OpenFile(ctx context.Context, name string, flag int, perm os.FileMode) (File, error) {
+	if name = d.resolve(name); name == "" {
+		return nil, os.ErrNotExist
+	}
+	f, err := os.OpenFile(name, flag, perm)
+	if err != nil {
+		return nil, err
+	}
+	return f, nil
+}
+
+func (d Dir) RemoveAll(ctx context.Context, name string) error {
+	if name = d.resolve(name); name == "" {
+		return os.ErrNotExist
+	}
+	if name == filepath.Clean(string(d)) {
+		// Prohibit removing the virtual root directory.
+		return os.ErrInvalid
+	}
+	return os.RemoveAll(name)
+}
+
+func (d Dir) Rename(ctx context.Context, oldName, newName string) error {
+	if oldName = d.resolve(oldName); oldName == "" {
+		return os.ErrNotExist
+	}
+	if newName = d.resolve(newName); newName == "" {
+		return os.ErrNotExist
+	}
+	if root := filepath.Clean(string(d)); root == oldName || root == newName {
+		// Prohibit renaming from or to the virtual root directory.
+		return os.ErrInvalid
+	}
+	return os.Rename(oldName, newName)
+}
+
+func (d Dir) Stat(ctx context.Context, name string) (os.FileInfo, error) {
+	if name = d.resolve(name); name == "" {
+		return nil, os.ErrNotExist
+	}
+	return os.Stat(name)
+}
+
+// NewMemFS returns a new in-memory FileSystem implementation.
+func NewMemFS() FileSystem {
+	return &memFS{
+		root: memFSNode{
+			children: make(map[string]*memFSNode),
+			mode:     0660 | os.ModeDir,
+			modTime:  time.Now(),
+		},
+	}
+}
+
+// A memFS implements FileSystem, storing all metadata and actual file data
+// in-memory. No limits on filesystem size are used, so it is not recommended
+// this be used where the clients are untrusted.
+//
+// Concurrent access is permitted. The tree structure is protected by a mutex,
+// and each node's contents and metadata are protected by a per-node mutex.
+//
+// TODO: Enforce file permissions.
+type memFS struct {
+	mu   sync.Mutex
+	root memFSNode
+}
+
+// TODO: clean up and rationalize the walk/find code.
+
+// walk walks the directory tree for the fullname, calling f at each step. If f
+// returns an error, the walk will be aborted and return that same error.
+//
+// dir is the directory at that step, frag is the name fragment, and final is
+// whether it is the final step. For example, walking "/foo/bar/x" will result
+// in 3 calls to f:
+//   - "/", "foo", false
+//   - "/foo/", "bar", false
+//   - "/foo/bar/", "x", true
+// The frag argument will be empty only if dir is the root node and the walk
+// ends at that root node.
+func (fs *memFS) walk(op, fullname string, f func(dir *memFSNode, frag string, final bool) error) error {
+	original := fullname
+	fullname = slashClean(fullname)
+
+	// Strip any leading "/"s to make fullname a relative path, as the walk
+	// starts at fs.root.
+	if fullname[0] == '/' {
+		fullname = fullname[1:]
+	}
+	dir := &fs.root
+
+	for {
+		frag, remaining := fullname, ""
+		i := strings.IndexRune(fullname, '/')
+		final := i < 0
+		if !final {
+			frag, remaining = fullname[:i], fullname[i+1:]
+		}
+		if frag == "" && dir != &fs.root {
+			panic("webdav: empty path fragment for a clean path")
+		}
+		if err := f(dir, frag, final); err != nil {
+			return &os.PathError{
+				Op:   op,
+				Path: original,
+				Err:  err,
+			}
+		}
+		if final {
+			break
+		}
+		child := dir.children[frag]
+		if child == nil {
+			return &os.PathError{
+				Op:   op,
+				Path: original,
+				Err:  os.ErrNotExist,
+			}
+		}
+		if !child.mode.IsDir() {
+			return &os.PathError{
+				Op:   op,
+				Path: original,
+				Err:  os.ErrInvalid,
+			}
+		}
+		dir, fullname = child, remaining
+	}
+	return nil
+}
+
+// find returns the parent of the named node and the relative name fragment
+// from the parent to the child. For example, if finding "/foo/bar/baz" then
+// parent will be the node for "/foo/bar" and frag will be "baz".
+//
+// If the fullname names the root node, then parent, frag and err will be zero.
+//
+// find returns an error if the parent does not already exist or the parent
+// isn't a directory, but it will not return an error per se if the child does
+// not already exist. The error returned is either nil or an *os.PathError
+// whose Op is op.
+func (fs *memFS) find(op, fullname string) (parent *memFSNode, frag string, err error) {
+	err = fs.walk(op, fullname, func(parent0 *memFSNode, frag0 string, final bool) error {
+		if !final {
+			return nil
+		}
+		if frag0 != "" {
+			parent, frag = parent0, frag0
+		}
+		return nil
+	})
+	return parent, frag, err
+}
+
+func (fs *memFS) Mkdir(ctx context.Context, name string, perm os.FileMode) error {
+	fs.mu.Lock()
+	defer fs.mu.Unlock()
+
+	dir, frag, err := fs.find("mkdir", name)
+	if err != nil {
+		return err
+	}
+	if dir == nil {
+		// We can't create the root.
+		return os.ErrInvalid
+	}
+	if _, ok := dir.children[frag]; ok {
+		return os.ErrExist
+	}
+	dir.children[frag] = &memFSNode{
+		children: make(map[string]*memFSNode),
+		mode:     perm.Perm() | os.ModeDir,
+		modTime:  time.Now(),
+	}
+	return nil
+}
+
+func (fs *memFS) OpenFile(ctx context.Context, name string, flag int, perm os.FileMode) (File, error) {
+	fs.mu.Lock()
+	defer fs.mu.Unlock()
+
+	dir, frag, err := fs.find("open", name)
+	if err != nil {
+		return nil, err
+	}
+	var n *memFSNode
+	if dir == nil {
+		// We're opening the root.
+		if flag&(os.O_WRONLY|os.O_RDWR) != 0 {
+			return nil, os.ErrPermission
+		}
+		n, frag = &fs.root, "/"
+
+	} else {
+		n = dir.children[frag]
+		if flag&(os.O_SYNC|os.O_APPEND) != 0 {
+			// memFile doesn't support these flags yet.
+			return nil, os.ErrInvalid
+		}
+		if flag&os.O_CREATE != 0 {
+			if flag&os.O_EXCL != 0 && n != nil {
+				return nil, os.ErrExist
+			}
+			if n == nil {
+				n = &memFSNode{
+					mode: perm.Perm(),
+				}
+				dir.children[frag] = n
+			}
+		}
+		if n == nil {
+			return nil, os.ErrNotExist
+		}
+		if flag&(os.O_WRONLY|os.O_RDWR) != 0 && flag&os.O_TRUNC != 0 {
+			n.mu.Lock()
+			n.data = nil
+			n.mu.Unlock()
+		}
+	}
+
+	children := make([]os.FileInfo, 0, len(n.children))
+	for cName, c := range n.children {
+		children = append(children, c.stat(cName))
+	}
+	return &memFile{
+		n:                n,
+		nameSnapshot:     frag,
+		childrenSnapshot: children,
+	}, nil
+}
+
+func (fs *memFS) RemoveAll(ctx context.Context, name string) error {
+	fs.mu.Lock()
+	defer fs.mu.Unlock()
+
+	dir, frag, err := fs.find("remove", name)
+	if err != nil {
+		return err
+	}
+	if dir == nil {
+		// We can't remove the root.
+		return os.ErrInvalid
+	}
+	delete(dir.children, frag)
+	return nil
+}
+
+func (fs *memFS) Rename(ctx context.Context, oldName, newName string) error {
+	fs.mu.Lock()
+	defer fs.mu.Unlock()
+
+	oldName = slashClean(oldName)
+	newName = slashClean(newName)
+	if oldName == newName {
+		return nil
+	}
+	if strings.HasPrefix(newName, oldName+"/") {
+		// We can't rename oldName to be a sub-directory of itself.
+		return os.ErrInvalid
+	}
+
+	oDir, oFrag, err := fs.find("rename", oldName)
+	if err != nil {
+		return err
+	}
+	if oDir == nil {
+		// We can't rename from the root.
+		return os.ErrInvalid
+	}
+
+	nDir, nFrag, err := fs.find("rename", newName)
+	if err != nil {
+		return err
+	}
+	if nDir == nil {
+		// We can't rename to the root.
+		return os.ErrInvalid
+	}
+
+	oNode, ok := oDir.children[oFrag]
+	if !ok {
+		return os.ErrNotExist
+	}
+	if oNode.children != nil {
+		if nNode, ok := nDir.children[nFrag]; ok {
+			if nNode.children == nil {
+				return errNotADirectory
+			}
+			if len(nNode.children) != 0 {
+				return errDirectoryNotEmpty
+			}
+		}
+	}
+	delete(oDir.children, oFrag)
+	nDir.children[nFrag] = oNode
+	return nil
+}
+
+func (fs *memFS) Stat(ctx context.Context, name string) (os.FileInfo, error) {
+	fs.mu.Lock()
+	defer fs.mu.Unlock()
+
+	dir, frag, err := fs.find("stat", name)
+	if err != nil {
+		return nil, err
+	}
+	if dir == nil {
+		// We're stat'ting the root.
+		return fs.root.stat("/"), nil
+	}
+	if n, ok := dir.children[frag]; ok {
+		return n.stat(path.Base(name)), nil
+	}
+	return nil, os.ErrNotExist
+}
+
+// A memFSNode represents a single entry in the in-memory filesystem and also
+// implements os.FileInfo.
+type memFSNode struct {
+	// children is protected by memFS.mu.
+	children map[string]*memFSNode
+
+	mu        sync.Mutex
+	data      []byte
+	mode      os.FileMode
+	modTime   time.Time
+	deadProps map[xml.Name]Property
+}
+
+func (n *memFSNode) stat(name string) *memFileInfo {
+	n.mu.Lock()
+	defer n.mu.Unlock()
+	return &memFileInfo{
+		name:    name,
+		size:    int64(len(n.data)),
+		mode:    n.mode,
+		modTime: n.modTime,
+	}
+}
+
+func (n *memFSNode) DeadProps() (map[xml.Name]Property, error) {
+	n.mu.Lock()
+	defer n.mu.Unlock()
+	if len(n.deadProps) == 0 {
+		return nil, nil
+	}
+	ret := make(map[xml.Name]Property, len(n.deadProps))
+	for k, v := range n.deadProps {
+		ret[k] = v
+	}
+	return ret, nil
+}
+
+func (n *memFSNode) Patch(patches []Proppatch) ([]Propstat, error) {
+	n.mu.Lock()
+	defer n.mu.Unlock()
+	pstat := Propstat{Status: http.StatusOK}
+	for _, patch := range patches {
+		for _, p := range patch.Props {
+			pstat.Props = append(pstat.Props, Property{XMLName: p.XMLName})
+			if patch.Remove {
+				delete(n.deadProps, p.XMLName)
+				continue
+			}
+			if n.deadProps == nil {
+				n.deadProps = map[xml.Name]Property{}
+			}
+			n.deadProps[p.XMLName] = p
+		}
+	}
+	return []Propstat{pstat}, nil
+}
+
+type memFileInfo struct {
+	name    string
+	size    int64
+	mode    os.FileMode
+	modTime time.Time
+}
+
+func (f *memFileInfo) Name() string       { return f.name }
+func (f *memFileInfo) Size() int64        { return f.size }
+func (f *memFileInfo) Mode() os.FileMode  { return f.mode }
+func (f *memFileInfo) ModTime() time.Time { return f.modTime }
+func (f *memFileInfo) IsDir() bool        { return f.mode.IsDir() }
+func (f *memFileInfo) Sys() interface{}   { return nil }
+
+// A memFile is a File implementation for a memFSNode. It is a per-file (not
+// per-node) read/write position, and a snapshot of the memFS' tree structure
+// (a node's name and children) for that node.
+type memFile struct {
+	n                *memFSNode
+	nameSnapshot     string
+	childrenSnapshot []os.FileInfo
+	// pos is protected by n.mu.
+	pos int
+}
+
+// A *memFile implements the optional DeadPropsHolder interface.
+var _ DeadPropsHolder = (*memFile)(nil)
+
+func (f *memFile) DeadProps() (map[xml.Name]Property, error)     { return f.n.DeadProps() }
+func (f *memFile) Patch(patches []Proppatch) ([]Propstat, error) { return f.n.Patch(patches) }
+
+func (f *memFile) Close() error {
+	return nil
+}
+
+func (f *memFile) Read(p []byte) (int, error) {
+	f.n.mu.Lock()
+	defer f.n.mu.Unlock()
+	if f.n.mode.IsDir() {
+		return 0, os.ErrInvalid
+	}
+	if f.pos >= len(f.n.data) {
+		return 0, io.EOF
+	}
+	n := copy(p, f.n.data[f.pos:])
+	f.pos += n
+	return n, nil
+}
+
+func (f *memFile) Readdir(count int) ([]os.FileInfo, error) {
+	f.n.mu.Lock()
+	defer f.n.mu.Unlock()
+	if !f.n.mode.IsDir() {
+		return nil, os.ErrInvalid
+	}
+	old := f.pos
+	if old >= len(f.childrenSnapshot) {
+		// The os.File Readdir docs say that at the end of a directory,
+		// the error is io.EOF if count > 0 and nil if count <= 0.
+		if count > 0 {
+			return nil, io.EOF
+		}
+		return nil, nil
+	}
+	if count > 0 {
+		f.pos += count
+		if f.pos > len(f.childrenSnapshot) {
+			f.pos = len(f.childrenSnapshot)
+		}
+	} else {
+		f.pos = len(f.childrenSnapshot)
+		old = 0
+	}
+	return f.childrenSnapshot[old:f.pos], nil
+}
+
+func (f *memFile) Seek(offset int64, whence int) (int64, error) {
+	f.n.mu.Lock()
+	defer f.n.mu.Unlock()
+	npos := f.pos
+	// TODO: How to handle offsets greater than the size of system int?
+	switch whence {
+	case os.SEEK_SET:
+		npos = int(offset)
+	case os.SEEK_CUR:
+		npos += int(offset)
+	case os.SEEK_END:
+		npos = len(f.n.data) + int(offset)
+	default:
+		npos = -1
+	}
+	if npos < 0 {
+		return 0, os.ErrInvalid
+	}
+	f.pos = npos
+	return int64(f.pos), nil
+}
+
+func (f *memFile) Stat() (os.FileInfo, error) {
+	return f.n.stat(f.nameSnapshot), nil
+}
+
+func (f *memFile) Write(p []byte) (int, error) {
+	lenp := len(p)
+	f.n.mu.Lock()
+	defer f.n.mu.Unlock()
+
+	if f.n.mode.IsDir() {
+		return 0, os.ErrInvalid
+	}
+	if f.pos < len(f.n.data) {
+		n := copy(f.n.data[f.pos:], p)
+		f.pos += n
+		p = p[n:]
+	} else if f.pos > len(f.n.data) {
+		// Write permits the creation of holes, if we've seek'ed past the
+		// existing end of file.
+		if f.pos <= cap(f.n.data) {
+			oldLen := len(f.n.data)
+			f.n.data = f.n.data[:f.pos]
+			hole := f.n.data[oldLen:]
+			for i := range hole {
+				hole[i] = 0
+			}
+		} else {
+			d := make([]byte, f.pos, f.pos+len(p))
+			copy(d, f.n.data)
+			f.n.data = d
+		}
+	}
+
+	if len(p) > 0 {
+		// We should only get here if f.pos == len(f.n.data).
+		f.n.data = append(f.n.data, p...)
+		f.pos = len(f.n.data)
+	}
+	f.n.modTime = time.Now()
+	return lenp, nil
+}
+
+// moveFiles moves files and/or directories from src to dst.
+//
+// See section 9.9.4 for when various HTTP status codes apply.
+func moveFiles(ctx context.Context, fs FileSystem, src, dst string, overwrite bool) (status int, err error) {
+	created := false
+	if _, err := fs.Stat(ctx, dst); err != nil {
+		if !os.IsNotExist(err) {
+			return http.StatusForbidden, err
+		}
+		created = true
+	} else if overwrite {
+		// Section 9.9.3 says that "If a resource exists at the destination
+		// and the Overwrite header is "T", then prior to performing the move,
+		// the server must perform a DELETE with "Depth: infinity" on the
+		// destination resource.
+		if err := fs.RemoveAll(ctx, dst); err != nil {
+			return http.StatusForbidden, err
+		}
+	} else {
+		return http.StatusPreconditionFailed, os.ErrExist
+	}
+	if err := fs.Rename(ctx, src, dst); err != nil {
+		return http.StatusForbidden, err
+	}
+	if created {
+		return http.StatusCreated, nil
+	}
+	return http.StatusNoContent, nil
+}
+
+func copyProps(dst, src File) error {
+	d, ok := dst.(DeadPropsHolder)
+	if !ok {
+		return nil
+	}
+	s, ok := src.(DeadPropsHolder)
+	if !ok {
+		return nil
+	}
+	m, err := s.DeadProps()
+	if err != nil {
+		return err
+	}
+	props := make([]Property, 0, len(m))
+	for _, prop := range m {
+		props = append(props, prop)
+	}
+	_, err = d.Patch([]Proppatch{{Props: props}})
+	return err
+}
+
+// copyFiles copies files and/or directories from src to dst.
+//
+// See section 9.8.5 for when various HTTP status codes apply.
+func copyFiles(ctx context.Context, fs FileSystem, src, dst string, overwrite bool, depth int, recursion int) (status int, err error) {
+	if recursion == 1000 {
+		return http.StatusInternalServerError, errRecursionTooDeep
+	}
+	recursion++
+
+	// TODO: section 9.8.3 says that "Note that an infinite-depth COPY of /A/
+	// into /A/B/ could lead to infinite recursion if not handled correctly."
+
+	srcFile, err := fs.OpenFile(ctx, src, os.O_RDONLY, 0)
+	if err != nil {
+		if os.IsNotExist(err) {
+			return http.StatusNotFound, err
+		}
+		return http.StatusInternalServerError, err
+	}
+	defer srcFile.Close()
+	srcStat, err := srcFile.Stat()
+	if err != nil {
+		if os.IsNotExist(err) {
+			return http.StatusNotFound, err
+		}
+		return http.StatusInternalServerError, err
+	}
+	srcPerm := srcStat.Mode() & os.ModePerm
+
+	created := false
+	if _, err := fs.Stat(ctx, dst); err != nil {
+		if os.IsNotExist(err) {
+			created = true
+		} else {
+			return http.StatusForbidden, err
+		}
+	} else {
+		if !overwrite {
+			return http.StatusPreconditionFailed, os.ErrExist
+		}
+		if err := fs.RemoveAll(ctx, dst); err != nil && !os.IsNotExist(err) {
+			return http.StatusForbidden, err
+		}
+	}
+
+	if srcStat.IsDir() {
+		if err := fs.Mkdir(ctx, dst, srcPerm); err != nil {
+			return http.StatusForbidden, err
+		}
+		if depth == infiniteDepth {
+			children, err := srcFile.Readdir(-1)
+			if err != nil {
+				return http.StatusForbidden, err
+			}
+			for _, c := range children {
+				name := c.Name()
+				s := path.Join(src, name)
+				d := path.Join(dst, name)
+				cStatus, cErr := copyFiles(ctx, fs, s, d, overwrite, depth, recursion)
+				if cErr != nil {
+					// TODO: MultiStatus.
+					return cStatus, cErr
+				}
+			}
+		}
+
+	} else {
+		dstFile, err := fs.OpenFile(ctx, dst, os.O_RDWR|os.O_CREATE|os.O_TRUNC, srcPerm)
+		if err != nil {
+			if os.IsNotExist(err) {
+				return http.StatusConflict, err
+			}
+			return http.StatusForbidden, err
+
+		}
+		_, copyErr := io.Copy(dstFile, srcFile)
+		propsErr := copyProps(dstFile, srcFile)
+		closeErr := dstFile.Close()
+		if copyErr != nil {
+			return http.StatusInternalServerError, copyErr
+		}
+		if propsErr != nil {
+			return http.StatusInternalServerError, propsErr
+		}
+		if closeErr != nil {
+			return http.StatusInternalServerError, closeErr
+		}
+	}
+
+	if created {
+		return http.StatusCreated, nil
+	}
+	return http.StatusNoContent, nil
+}
+
+// walkFS traverses filesystem fs starting at name up to depth levels.
+//
+// Allowed values for depth are 0, 1 or infiniteDepth. For each visited node,
+// walkFS calls walkFn. If a visited file system node is a directory and
+// walkFn returns filepath.SkipDir, walkFS will skip traversal of this node.
+func walkFS(ctx context.Context, fs FileSystem, depth int, name string, info os.FileInfo, walkFn filepath.WalkFunc) error {
+	// This implementation is based on Walk's code in the standard path/filepath package.
+	err := walkFn(name, info, nil)
+	if err != nil {
+		if info.IsDir() && err == filepath.SkipDir {
+			return nil
+		}
+		return err
+	}
+	if !info.IsDir() || depth == 0 {
+		return nil
+	}
+	if depth == 1 {
+		depth = 0
+	}
+
+	// Read directory names.
+	f, err := fs.OpenFile(ctx, name, os.O_RDONLY, 0)
+	if err != nil {
+		return walkFn(name, info, err)
+	}
+	fileInfos, err := f.Readdir(0)
+	f.Close()
+	if err != nil {
+		return walkFn(name, info, err)
+	}
+
+	for _, fileInfo := range fileInfos {
+		filename := path.Join(name, fileInfo.Name())
+		fileInfo, err := fs.Stat(ctx, filename)
+		if err != nil {
+			if err := walkFn(filename, fileInfo, err); err != nil && err != filepath.SkipDir {
+				return err
+			}
+		} else {
+			err = walkFS(ctx, fs, depth, filename, fileInfo, walkFn)
+			if err != nil {
+				if !fileInfo.IsDir() || err != filepath.SkipDir {
+					return err
+				}
+			}
+		}
+	}
+	return nil
+}

vendor/golang.org/x/net/webdav/file_go1.6.go

@@ -0,0 +1,17 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !go1.7
+
+package webdav
+
+import (
+	"net/http"
+
+	"golang.org/x/net/context"
+)
+
+func getContext(r *http.Request) context.Context {
+	return context.Background()
+}

vendor/golang.org/x/net/webdav/file_go1.7.go

@@ -0,0 +1,16 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build go1.7
+
+package webdav
+
+import (
+	"context"
+	"net/http"
+)
+
+func getContext(r *http.Request) context.Context {
+	return r.Context()
+}

vendor/golang.org/x/net/webdav/if.go

@@ -0,0 +1,173 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package webdav
+
+// The If header is covered by Section 10.4.
+// http://www.webdav.org/specs/rfc4918.html#HEADER_If
+
+import (
+	"strings"
+)
+
+// ifHeader is a disjunction (OR) of ifLists.
+type ifHeader struct {
+	lists []ifList
+}
+
+// ifList is a conjunction (AND) of Conditions, and an optional resource tag.
+type ifList struct {
+	resourceTag string
+	conditions  []Condition
+}
+
+// parseIfHeader parses the "If: foo bar" HTTP header. The httpHeader string
+// should omit the "If:" prefix and have any "\r\n"s collapsed to a " ", as is
+// returned by req.Header.Get("If") for a http.Request req.
+func parseIfHeader(httpHeader string) (h ifHeader, ok bool) {
+	s := strings.TrimSpace(httpHeader)
+	switch tokenType, _, _ := lex(s); tokenType {
+	case '(':
+		return parseNoTagLists(s)
+	case angleTokenType:
+		return parseTaggedLists(s)
+	default:
+		return ifHeader{}, false
+	}
+}
+
+func parseNoTagLists(s string) (h ifHeader, ok bool) {
+	for {
+		l, remaining, ok := parseList(s)
+		if !ok {
+			return ifHeader{}, false
+		}
+		h.lists = append(h.lists, l)
+		if remaining == "" {
+			return h, true
+		}
+		s = remaining
+	}
+}
+
+func parseTaggedLists(s string) (h ifHeader, ok bool) {
+	resourceTag, n := "", 0
+	for first := true; ; first = false {
+		tokenType, tokenStr, remaining := lex(s)
+		switch tokenType {
+		case angleTokenType:
+			if !first && n == 0 {
+				return ifHeader{}, false
+			}
+			resourceTag, n = tokenStr, 0
+			s = remaining
+		case '(':
+			n++
+			l, remaining, ok := parseList(s)
+			if !ok {
+				return ifHeader{}, false
+			}
+			l.resourceTag = resourceTag
+			h.lists = append(h.lists, l)
+			if remaining == "" {
+				return h, true
+			}
+			s = remaining
+		default:
+			return ifHeader{}, false
+		}
+	}
+}
+
+func parseList(s string) (l ifList, remaining string, ok bool) {
+	tokenType, _, s := lex(s)
+	if tokenType != '(' {
+		return ifList{}, "", false
+	}
+	for {
+		tokenType, _, remaining = lex(s)
+		if tokenType == ')' {
+			if len(l.conditions) == 0 {
+				return ifList{}, "", false
+			}
+			return l, remaining, true
+		}
+		c, remaining, ok := parseCondition(s)
+		if !ok {
+			return ifList{}, "", false
+		}
+		l.conditions = append(l.conditions, c)
+		s = remaining
+	}
+}
+
+func parseCondition(s string) (c Condition, remaining string, ok bool) {
+	tokenType, tokenStr, s := lex(s)
+	if tokenType == notTokenType {
+		c.Not = true
+		tokenType, tokenStr, s = lex(s)
+	}
+	switch tokenType {
+	case strTokenType, angleTokenType:
+		c.Token = tokenStr
+	case squareTokenType:
+		c.ETag = tokenStr
+	default:
+		return Condition{}, "", false
+	}
+	return c, s, true
+}
+
+// Single-rune tokens like '(' or ')' have a token type equal to their rune.
+// All other tokens have a negative token type.
+const (
+	errTokenType    = rune(-1)
+	eofTokenType    = rune(-2)
+	strTokenType    = rune(-3)
+	notTokenType    = rune(-4)
+	angleTokenType  = rune(-5)
+	squareTokenType = rune(-6)
+)
+
+func lex(s string) (tokenType rune, tokenStr string, remaining string) {
+	// The net/textproto Reader that parses the HTTP header will collapse
+	// Linear White Space that spans multiple "\r\n" lines to a single " ",
+	// so we don't need to look for '\r' or '\n'.
+	for len(s) > 0 && (s[0] == '\t' || s[0] == ' ') {
+		s = s[1:]
+	}
+	if len(s) == 0 {
+		return eofTokenType, "", ""
+	}
+	i := 0
+loop:
+	for ; i < len(s); i++ {
+		switch s[i] {
+		case '\t', ' ', '(', ')', '<', '>', '[', ']':
+			break loop
+		}
+	}
+
+	if i != 0 {
+		tokenStr, remaining = s[:i], s[i:]
+		if tokenStr == "Not" {
+			return notTokenType, "", remaining
+		}
+		return strTokenType, tokenStr, remaining
+	}
+
+	j := 0
+	switch s[0] {
+	case '<':
+		j, tokenType = strings.IndexByte(s, '>'), angleTokenType
+	case '[':
+		j, tokenType = strings.IndexByte(s, ']'), squareTokenType
+	default:
+		return rune(s[0]), "", s[1:]
+	}
+	if j < 0 {
+		return errTokenType, "", ""
+	}
+	return tokenType, s[1:j], s[j+1:]
+}

vendor/golang.org/x/net/webdav/internal/xml/README

@@ -0,0 +1,11 @@
+This is a fork of the encoding/xml package at ca1d6c4, the last commit before
+https://go.googlesource.com/go/+/c0d6d33 "encoding/xml: restore Go 1.4 name
+space behavior" made late in the lead-up to the Go 1.5 release.
+
+The list of encoding/xml changes is at
+https://go.googlesource.com/go/+log/master/src/encoding/xml
+
+This fork is temporary, and I (nigeltao) expect to revert it after Go 1.6 is
+released.
+
+See http://golang.org/issue/11841

vendor/golang.org/x/net/webdav/internal/xml/read.go

@@ -0,0 +1,692 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package xml
+
+import (
+	"bytes"
+	"encoding"
+	"errors"
+	"fmt"
+	"reflect"
+	"strconv"
+	"strings"
+)
+
+// BUG(rsc): Mapping between XML elements and data structures is inherently flawed:
+// an XML element is an order-dependent collection of anonymous
+// values, while a data structure is an order-independent collection
+// of named values.
+// See package json for a textual representation more suitable
+// to data structures.
+
+// Unmarshal parses the XML-encoded data and stores the result in
+// the value pointed to by v, which must be an arbitrary struct,
+// slice, or string. Well-formed data that does not fit into v is
+// discarded.
+//
+// Because Unmarshal uses the reflect package, it can only assign
+// to exported (upper case) fields. Unmarshal uses a case-sensitive
+// comparison to match XML element names to tag values and struct
+// field names.
+//
+// Unmarshal maps an XML element to a struct using the following rules.
+// In the rules, the tag of a field refers to the value associated with the
+// key 'xml' in the struct field's tag (see the example above).
+//
+//   * If the struct has a field of type []byte or string with tag
+//      ",innerxml", Unmarshal accumulates the raw XML nested inside the
+//      element in that field. The rest of the rules still apply.
+//
+//   * If the struct has a field named XMLName of type xml.Name,
+//      Unmarshal records the element name in that field.
+//
+//   * If the XMLName field has an associated tag of the form
+//      "name" or "namespace-URL name", the XML element must have
+//      the given name (and, optionally, name space) or else Unmarshal
+//      returns an error.
+//
+//   * If the XML element has an attribute whose name matches a
+//      struct field name with an associated tag containing ",attr" or
+//      the explicit name in a struct field tag of the form "name,attr",
+//      Unmarshal records the attribute value in that field.
+//
+//   * If the XML element contains character data, that data is
+//      accumulated in the first struct field that has tag ",chardata".
+//      The struct field may have type []byte or string.
+//      If there is no such field, the character data is discarded.
+//
+//   * If the XML element contains comments, they are accumulated in
+//      the first struct field that has tag ",comment".  The struct
+//      field may have type []byte or string. If there is no such
+//      field, the comments are discarded.
+//
+//   * If the XML element contains a sub-element whose name matches
+//      the prefix of a tag formatted as "a" or "a>b>c", unmarshal
+//      will descend into the XML structure looking for elements with the
+//      given names, and will map the innermost elements to that struct
+//      field. A tag starting with ">" is equivalent to one starting
+//      with the field name followed by ">".
+//
+//   * If the XML element contains a sub-element whose name matches
+//      a struct field's XMLName tag and the struct field has no
+//      explicit name tag as per the previous rule, unmarshal maps
+//      the sub-element to that struct field.
+//
+//   * If the XML element contains a sub-element whose name matches a
+//      field without any mode flags (",attr", ",chardata", etc), Unmarshal
+//      maps the sub-element to that struct field.
+//
+//   * If the XML element contains a sub-element that hasn't matched any
+//      of the above rules and the struct has a field with tag ",any",
+//      unmarshal maps the sub-element to that struct field.
+//
+//   * An anonymous struct field is handled as if the fields of its
+//      value were part of the outer struct.
+//
+//   * A struct field with tag "-" is never unmarshalled into.
+//
+// Unmarshal maps an XML element to a string or []byte by saving the
+// concatenation of that element's character data in the string or
+// []byte. The saved []byte is never nil.
+//
+// Unmarshal maps an attribute value to a string or []byte by saving
+// the value in the string or slice.
+//
+// Unmarshal maps an XML element to a slice by extending the length of
+// the slice and mapping the element to the newly created value.
+//
+// Unmarshal maps an XML element or attribute value to a bool by
+// setting it to the boolean value represented by the string.
+//
+// Unmarshal maps an XML element or attribute value to an integer or
+// floating-point field by setting the field to the result of
+// interpreting the string value in decimal. There is no check for
+// overflow.
+//
+// Unmarshal maps an XML element to an xml.Name by recording the
+// element name.
+//
+// Unmarshal maps an XML element to a pointer by setting the pointer
+// to a freshly allocated value and then mapping the element to that value.
+//
+func Unmarshal(data []byte, v interface{}) error {
+	return NewDecoder(bytes.NewReader(data)).Decode(v)
+}
+
+// Decode works like xml.Unmarshal, except it reads the decoder
+// stream to find the start element.
+func (d *Decoder) Decode(v interface{}) error {
+	return d.DecodeElement(v, nil)
+}
+
+// DecodeElement works like xml.Unmarshal except that it takes
+// a pointer to the start XML element to decode into v.
+// It is useful when a client reads some raw XML tokens itself
+// but also wants to defer to Unmarshal for some elements.
+func (d *Decoder) DecodeElement(v interface{}, start *StartElement) error {
+	val := reflect.ValueOf(v)
+	if val.Kind() != reflect.Ptr {
+		return errors.New("non-pointer passed to Unmarshal")
+	}
+	return d.unmarshal(val.Elem(), start)
+}
+
+// An UnmarshalError represents an error in the unmarshalling process.
+type UnmarshalError string
+
+func (e UnmarshalError) Error() string { return string(e) }
+
+// Unmarshaler is the interface implemented by objects that can unmarshal
+// an XML element description of themselves.
+//
+// UnmarshalXML decodes a single XML element
+// beginning with the given start element.
+// If it returns an error, the outer call to Unmarshal stops and
+// returns that error.
+// UnmarshalXML must consume exactly one XML element.
+// One common implementation strategy is to unmarshal into
+// a separate value with a layout matching the expected XML
+// using d.DecodeElement,  and then to copy the data from
+// that value into the receiver.
+// Another common strategy is to use d.Token to process the
+// XML object one token at a time.
+// UnmarshalXML may not use d.RawToken.
+type Unmarshaler interface {
+	UnmarshalXML(d *Decoder, start StartElement) error
+}
+
+// UnmarshalerAttr is the interface implemented by objects that can unmarshal
+// an XML attribute description of themselves.
+//
+// UnmarshalXMLAttr decodes a single XML attribute.
+// If it returns an error, the outer call to Unmarshal stops and
+// returns that error.
+// UnmarshalXMLAttr is used only for struct fields with the
+// "attr" option in the field tag.
+type UnmarshalerAttr interface {
+	UnmarshalXMLAttr(attr Attr) error
+}
+
+// receiverType returns the receiver type to use in an expression like "%s.MethodName".
+func receiverType(val interface{}) string {
+	t := reflect.TypeOf(val)
+	if t.Name() != "" {
+		return t.String()
+	}
+	return "(" + t.String() + ")"
+}
+
+// unmarshalInterface unmarshals a single XML element into val.
+// start is the opening tag of the element.
+func (p *Decoder) unmarshalInterface(val Unmarshaler, start *StartElement) error {
+	// Record that decoder must stop at end tag corresponding to start.
+	p.pushEOF()
+
+	p.unmarshalDepth++
+	err := val.UnmarshalXML(p, *start)
+	p.unmarshalDepth--
+	if err != nil {
+		p.popEOF()
+		return err
+	}
+
+	if !p.popEOF() {
+		return fmt.Errorf("xml: %s.UnmarshalXML did not consume entire <%s> element", receiverType(val), start.Name.Local)
+	}
+
+	return nil
+}
+
+// unmarshalTextInterface unmarshals a single XML element into val.
+// The chardata contained in the element (but not its children)
+// is passed to the text unmarshaler.
+func (p *Decoder) unmarshalTextInterface(val encoding.TextUnmarshaler, start *StartElement) error {
+	var buf []byte
+	depth := 1
+	for depth > 0 {
+		t, err := p.Token()
+		if err != nil {
+			return err
+		}
+		switch t := t.(type) {
+		case CharData:
+			if depth == 1 {
+				buf = append(buf, t...)
+			}
+		case StartElement:
+			depth++
+		case EndElement:
+			depth--
+		}
+	}
+	return val.UnmarshalText(buf)
+}
+
+// unmarshalAttr unmarshals a single XML attribute into val.
+func (p *Decoder) unmarshalAttr(val reflect.Value, attr Attr) error {
+	if val.Kind() == reflect.Ptr {
+		if val.IsNil() {
+			val.Set(reflect.New(val.Type().Elem()))
+		}
+		val = val.Elem()
+	}
+
+	if val.CanInterface() && val.Type().Implements(unmarshalerAttrType) {
+		// This is an unmarshaler with a non-pointer receiver,
+		// so it's likely to be incorrect, but we do what we're told.
+		return val.Interface().(UnmarshalerAttr).UnmarshalXMLAttr(attr)
+	}
+	if val.CanAddr() {
+		pv := val.Addr()
+		if pv.CanInterface() && pv.Type().Implements(unmarshalerAttrType) {
+			return pv.Interface().(UnmarshalerAttr).UnmarshalXMLAttr(attr)
+		}
+	}
+
+	// Not an UnmarshalerAttr; try encoding.TextUnmarshaler.
+	if val.CanInterface() && val.Type().Implements(textUnmarshalerType) {
+		// This is an unmarshaler with a non-pointer receiver,
+		// so it's likely to be incorrect, but we do what we're told.
+		return val.Interface().(encoding.TextUnmarshaler).UnmarshalText([]byte(attr.Value))
+	}
+	if val.CanAddr() {
+		pv := val.Addr()
+		if pv.CanInterface() && pv.Type().Implements(textUnmarshalerType) {
+			return pv.Interface().(encoding.TextUnmarshaler).UnmarshalText([]byte(attr.Value))
+		}
+	}
+
+	copyValue(val, []byte(attr.Value))
+	return nil
+}
+
+var (
+	unmarshalerType     = reflect.TypeOf((*Unmarshaler)(nil)).Elem()
+	unmarshalerAttrType = reflect.TypeOf((*UnmarshalerAttr)(nil)).Elem()
+	textUnmarshalerType = reflect.TypeOf((*encoding.TextUnmarshaler)(nil)).Elem()
+)
+
+// Unmarshal a single XML element into val.
+func (p *Decoder) unmarshal(val reflect.Value, start *StartElement) error {
+	// Find start element if we need it.
+	if start == nil {
+		for {
+			tok, err := p.Token()
+			if err != nil {
+				return err
+			}
+			if t, ok := tok.(StartElement); ok {
+				start = &t
+				break
+			}
+		}
+	}
+
+	// Load value from interface, but only if the result will be
+	// usefully addressable.
+	if val.Kind() == reflect.Interface && !val.IsNil() {
+		e := val.Elem()
+		if e.Kind() == reflect.Ptr && !e.IsNil() {
+			val = e
+		}
+	}
+
+	if val.Kind() == reflect.Ptr {
+		if val.IsNil() {
+			val.Set(reflect.New(val.Type().Elem()))
+		}
+		val = val.Elem()
+	}
+
+	if val.CanInterface() && val.Type().Implements(unmarshalerType) {
+		// This is an unmarshaler with a non-pointer receiver,
+		// so it's likely to be incorrect, but we do what we're told.
+		return p.unmarshalInterface(val.Interface().(Unmarshaler), start)
+	}
+
+	if val.CanAddr() {
+		pv := val.Addr()
+		if pv.CanInterface() && pv.Type().Implements(unmarshalerType) {
+			return p.unmarshalInterface(pv.Interface().(Unmarshaler), start)
+		}
+	}
+
+	if val.CanInterface() && val.Type().Implements(textUnmarshalerType) {
+		return p.unmarshalTextInterface(val.Interface().(encoding.TextUnmarshaler), start)
+	}
+
+	if val.CanAddr() {
+		pv := val.Addr()
+		if pv.CanInterface() && pv.Type().Implements(textUnmarshalerType) {
+			return p.unmarshalTextInterface(pv.Interface().(encoding.TextUnmarshaler), start)
+		}
+	}
+
+	var (
+		data         []byte
+		saveData     reflect.Value
+		comment      []byte
+		saveComment  reflect.Value
+		saveXML      reflect.Value
+		saveXMLIndex int
+		saveXMLData  []byte
+		saveAny      reflect.Value
+		sv           reflect.Value
+		tinfo        *typeInfo
+		err          error
+	)
+
+	switch v := val; v.Kind() {
+	default:
+		return errors.New("unknown type " + v.Type().String())
+
+	case reflect.Interface:
+		// TODO: For now, simply ignore the field. In the near
+		//       future we may choose to unmarshal the start
+		//       element on it, if not nil.
+		return p.Skip()
+
+	case reflect.Slice:
+		typ := v.Type()
+		if typ.Elem().Kind() == reflect.Uint8 {
+			// []byte
+			saveData = v
+			break
+		}
+
+		// Slice of element values.
+		// Grow slice.
+		n := v.Len()
+		if n >= v.Cap() {
+			ncap := 2 * n
+			if ncap < 4 {
+				ncap = 4
+			}
+			new := reflect.MakeSlice(typ, n, ncap)
+			reflect.Copy(new, v)
+			v.Set(new)
+		}
+		v.SetLen(n + 1)
+
+		// Recur to read element into slice.
+		if err := p.unmarshal(v.Index(n), start); err != nil {
+			v.SetLen(n)
+			return err
+		}
+		return nil
+
+	case reflect.Bool, reflect.Float32, reflect.Float64, reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64, reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr, reflect.String:
+		saveData = v
+
+	case reflect.Struct:
+		typ := v.Type()
+		if typ == nameType {
+			v.Set(reflect.ValueOf(start.Name))
+			break
+		}
+
+		sv = v
+		tinfo, err = getTypeInfo(typ)
+		if err != nil {
+			return err
+		}
+
+		// Validate and assign element name.
+		if tinfo.xmlname != nil {
+			finfo := tinfo.xmlname
+			if finfo.name != "" && finfo.name != start.Name.Local {
+				return UnmarshalError("expected element type <" + finfo.name + "> but have <" + start.Name.Local + ">")
+			}
+			if finfo.xmlns != "" && finfo.xmlns != start.Name.Space {
+				e := "expected element <" + finfo.name + "> in name space " + finfo.xmlns + " but have "
+				if start.Name.Space == "" {
+					e += "no name space"
+				} else {
+					e += start.Name.Space
+				}
+				return UnmarshalError(e)
+			}
+			fv := finfo.value(sv)
+			if _, ok := fv.Interface().(Name); ok {
+				fv.Set(reflect.ValueOf(start.Name))
+			}
+		}
+
+		// Assign attributes.
+		// Also, determine whether we need to save character data or comments.
+		for i := range tinfo.fields {
+			finfo := &tinfo.fields[i]
+			switch finfo.flags & fMode {
+			case fAttr:
+				strv := finfo.value(sv)
+				// Look for attribute.
+				for _, a := range start.Attr {
+					if a.Name.Local == finfo.name && (finfo.xmlns == "" || finfo.xmlns == a.Name.Space) {
+						if err := p.unmarshalAttr(strv, a); err != nil {
+							return err
+						}
+						break
+					}
+				}
+
+			case fCharData:
+				if !saveData.IsValid() {
+					saveData = finfo.value(sv)
+				}
+
+			case fComment:
+				if !saveComment.IsValid() {
+					saveComment = finfo.value(sv)
+				}
+
+			case fAny, fAny | fElement:
+				if !saveAny.IsValid() {
+					saveAny = finfo.value(sv)
+				}
+
+			case fInnerXml:
+				if !saveXML.IsValid() {
+					saveXML = finfo.value(sv)
+					if p.saved == nil {
+						saveXMLIndex = 0
+						p.saved = new(bytes.Buffer)
+					} else {
+						saveXMLIndex = p.savedOffset()
+					}
+				}
+			}
+		}
+	}
+
+	// Find end element.
+	// Process sub-elements along the way.
+Loop:
+	for {
+		var savedOffset int
+		if saveXML.IsValid() {
+			savedOffset = p.savedOffset()
+		}
+		tok, err := p.Token()
+		if err != nil {
+			return err
+		}
+		switch t := tok.(type) {
+		case StartElement:
+			consumed := false
+			if sv.IsValid() {
+				consumed, err = p.unmarshalPath(tinfo, sv, nil, &t)
+				if err != nil {
+					return err
+				}
+				if !consumed && saveAny.IsValid() {
+					consumed = true
+					if err := p.unmarshal(saveAny, &t); err != nil {
+						return err
+					}
+				}
+			}
+			if !consumed {
+				if err := p.Skip(); err != nil {
+					return err
+				}
+			}
+
+		case EndElement:
+			if saveXML.IsValid() {
+				saveXMLData = p.saved.Bytes()[saveXMLIndex:savedOffset]
+				if saveXMLIndex == 0 {
+					p.saved = nil
+				}
+			}
+			break Loop
+
+		case CharData:
+			if saveData.IsValid() {
+				data = append(data, t...)
+			}
+
+		case Comment:
+			if saveComment.IsValid() {
+				comment = append(comment, t...)
+			}
+		}
+	}
+
+	if saveData.IsValid() && saveData.CanInterface() && saveData.Type().Implements(textUnmarshalerType) {
+		if err := saveData.Interface().(encoding.TextUnmarshaler).UnmarshalText(data); err != nil {
+			return err
+		}
+		saveData = reflect.Value{}
+	}
+
+	if saveData.IsValid() && saveData.CanAddr() {
+		pv := saveData.Addr()
+		if pv.CanInterface() && pv.Type().Implements(textUnmarshalerType) {
+			if err := pv.Interface().(encoding.TextUnmarshaler).UnmarshalText(data); err != nil {
+				return err
+			}
+			saveData = reflect.Value{}
+		}
+	}
+
+	if err := copyValue(saveData, data); err != nil {
+		return err
+	}
+
+	switch t := saveComment; t.Kind() {
+	case reflect.String:
+		t.SetString(string(comment))
+	case reflect.Slice:
+		t.Set(reflect.ValueOf(comment))
+	}
+
+	switch t := saveXML; t.Kind() {
+	case reflect.String:
+		t.SetString(string(saveXMLData))
+	case reflect.Slice:
+		t.Set(reflect.ValueOf(saveXMLData))
+	}
+
+	return nil
+}
+
+func copyValue(dst reflect.Value, src []byte) (err error) {
+	dst0 := dst
+
+	if dst.Kind() == reflect.Ptr {
+		if dst.IsNil() {
+			dst.Set(reflect.New(dst.Type().Elem()))
+		}
+		dst = dst.Elem()
+	}
+
+	// Save accumulated data.
+	switch dst.Kind() {
+	case reflect.Invalid:
+		// Probably a comment.
+	default:
+		return errors.New("cannot unmarshal into " + dst0.Type().String())
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		itmp, err := strconv.ParseInt(string(src), 10, dst.Type().Bits())
+		if err != nil {
+			return err
+		}
+		dst.SetInt(itmp)
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		utmp, err := strconv.ParseUint(string(src), 10, dst.Type().Bits())
+		if err != nil {
+			return err
+		}
+		dst.SetUint(utmp)
+	case reflect.Float32, reflect.Float64:
+		ftmp, err := strconv.ParseFloat(string(src), dst.Type().Bits())
+		if err != nil {
+			return err
+		}
+		dst.SetFloat(ftmp)
+	case reflect.Bool:
+		value, err := strconv.ParseBool(strings.TrimSpace(string(src)))
+		if err != nil {
+			return err
+		}
+		dst.SetBool(value)
+	case reflect.String:
+		dst.SetString(string(src))
+	case reflect.Slice:
+		if len(src) == 0 {
+			// non-nil to flag presence
+			src = []byte{}
+		}
+		dst.SetBytes(src)
+	}
+	return nil
+}
+
+// unmarshalPath walks down an XML structure looking for wanted
+// paths, and calls unmarshal on them.
+// The consumed result tells whether XML elements have been consumed
+// from the Decoder until start's matching end element, or if it's
+// still untouched because start is uninteresting for sv's fields.
+func (p *Decoder) unmarshalPath(tinfo *typeInfo, sv reflect.Value, parents []string, start *StartElement) (consumed bool, err error) {
+	recurse := false
+Loop:
+	for i := range tinfo.fields {
+		finfo := &tinfo.fields[i]
+		if finfo.flags&fElement == 0 || len(finfo.parents) < len(parents) || finfo.xmlns != "" && finfo.xmlns != start.Name.Space {
+			continue
+		}
+		for j := range parents {
+			if parents[j] != finfo.parents[j] {
+				continue Loop
+			}
+		}
+		if len(finfo.parents) == len(parents) && finfo.name == start.Name.Local {
+			// It's a perfect match, unmarshal the field.
+			return true, p.unmarshal(finfo.value(sv), start)
+		}
+		if len(finfo.parents) > len(parents) && finfo.parents[len(parents)] == start.Name.Local {
+			// It's a prefix for the field. Break and recurse
+			// since it's not ok for one field path to be itself
+			// the prefix for another field path.
+			recurse = true
+
+			// We can reuse the same slice as long as we
+			// don't try to append to it.
+			parents = finfo.parents[:len(parents)+1]
+			break
+		}
+	}
+	if !recurse {
+		// We have no business with this element.
+		return false, nil
+	}
+	// The element is not a perfect match for any field, but one
+	// or more fields have the path to this element as a parent
+	// prefix. Recurse and attempt to match these.
+	for {
+		var tok Token
+		tok, err = p.Token()
+		if err != nil {
+			return true, err
+		}
+		switch t := tok.(type) {
+		case StartElement:
+			consumed2, err := p.unmarshalPath(tinfo, sv, parents, &t)
+			if err != nil {
+				return true, err
+			}
+			if !consumed2 {
+				if err := p.Skip(); err != nil {
+					return true, err
+				}
+			}
+		case EndElement:
+			return true, nil
+		}
+	}
+}
+
+// Skip reads tokens until it has consumed the end element
+// matching the most recent start element already consumed.
+// It recurs if it encounters a start element, so it can be used to
+// skip nested structures.
+// It returns nil if it finds an end element matching the start
+// element; otherwise it returns an error describing the problem.
+func (d *Decoder) Skip() error {
+	for {
+		tok, err := d.Token()
+		if err != nil {
+			return err
+		}
+		switch tok.(type) {
+		case StartElement:
+			if err := d.Skip(); err != nil {
+				return err
+			}
+		case EndElement:
+			return nil
+		}
+	}
+}

vendor/golang.org/x/net/webdav/internal/xml/typeinfo.go

@@ -0,0 +1,371 @@
+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package xml
+
+import (
+	"fmt"
+	"reflect"
+	"strings"
+	"sync"
+)
+
+// typeInfo holds details for the xml representation of a type.
+type typeInfo struct {
+	xmlname *fieldInfo
+	fields  []fieldInfo
+}
+
+// fieldInfo holds details for the xml representation of a single field.
+type fieldInfo struct {
+	idx     []int
+	name    string
+	xmlns   string
+	flags   fieldFlags
+	parents []string
+}
+
+type fieldFlags int
+
+const (
+	fElement fieldFlags = 1 << iota
+	fAttr
+	fCharData
+	fInnerXml
+	fComment
+	fAny
+
+	fOmitEmpty
+
+	fMode = fElement | fAttr | fCharData | fInnerXml | fComment | fAny
+)
+
+var tinfoMap = make(map[reflect.Type]*typeInfo)
+var tinfoLock sync.RWMutex
+
+var nameType = reflect.TypeOf(Name{})
+
+// getTypeInfo returns the typeInfo structure with details necessary
+// for marshalling and unmarshalling typ.
+func getTypeInfo(typ reflect.Type) (*typeInfo, error) {
+	tinfoLock.RLock()
+	tinfo, ok := tinfoMap[typ]
+	tinfoLock.RUnlock()
+	if ok {
+		return tinfo, nil
+	}
+	tinfo = &typeInfo{}
+	if typ.Kind() == reflect.Struct && typ != nameType {
+		n := typ.NumField()
+		for i := 0; i < n; i++ {
+			f := typ.Field(i)
+			if f.PkgPath != "" || f.Tag.Get("xml") == "-" {
+				continue // Private field
+			}
+
+			// For embedded structs, embed its fields.
+			if f.Anonymous {
+				t := f.Type
+				if t.Kind() == reflect.Ptr {
+					t = t.Elem()
+				}
+				if t.Kind() == reflect.Struct {
+					inner, err := getTypeInfo(t)
+					if err != nil {
+						return nil, err
+					}
+					if tinfo.xmlname == nil {
+						tinfo.xmlname = inner.xmlname
+					}
+					for _, finfo := range inner.fields {
+						finfo.idx = append([]int{i}, finfo.idx...)
+						if err := addFieldInfo(typ, tinfo, &finfo); err != nil {
+							return nil, err
+						}
+					}
+					continue
+				}
+			}
+
+			finfo, err := structFieldInfo(typ, &f)
+			if err != nil {
+				return nil, err
+			}
+
+			if f.Name == "XMLName" {
+				tinfo.xmlname = finfo
+				continue
+			}
+
+			// Add the field if it doesn't conflict with other fields.
+			if err := addFieldInfo(typ, tinfo, finfo); err != nil {
+				return nil, err
+			}
+		}
+	}
+	tinfoLock.Lock()
+	tinfoMap[typ] = tinfo
+	tinfoLock.Unlock()
+	return tinfo, nil
+}
+
+// structFieldInfo builds and returns a fieldInfo for f.
+func structFieldInfo(typ reflect.Type, f *reflect.StructField) (*fieldInfo, error) {
+	finfo := &fieldInfo{idx: f.Index}
+
+	// Split the tag from the xml namespace if necessary.
+	tag := f.Tag.Get("xml")
+	if i := strings.Index(tag, " "); i >= 0 {
+		finfo.xmlns, tag = tag[:i], tag[i+1:]
+	}
+
+	// Parse flags.
+	tokens := strings.Split(tag, ",")
+	if len(tokens) == 1 {
+		finfo.flags = fElement
+	} else {
+		tag = tokens[0]
+		for _, flag := range tokens[1:] {
+			switch flag {
+			case "attr":
+				finfo.flags |= fAttr
+			case "chardata":
+				finfo.flags |= fCharData
+			case "innerxml":
+				finfo.flags |= fInnerXml
+			case "comment":
+				finfo.flags |= fComment
+			case "any":
+				finfo.flags |= fAny
+			case "omitempty":
+				finfo.flags |= fOmitEmpty
+			}
+		}
+
+		// Validate the flags used.
+		valid := true
+		switch mode := finfo.flags & fMode; mode {
+		case 0:
+			finfo.flags |= fElement
+		case fAttr, fCharData, fInnerXml, fComment, fAny:
+			if f.Name == "XMLName" || tag != "" && mode != fAttr {
+				valid = false
+			}
+		default:
+			// This will also catch multiple modes in a single field.
+			valid = false
+		}
+		if finfo.flags&fMode == fAny {
+			finfo.flags |= fElement
+		}
+		if finfo.flags&fOmitEmpty != 0 && finfo.flags&(fElement|fAttr) == 0 {
+			valid = false
+		}
+		if !valid {
+			return nil, fmt.Errorf("xml: invalid tag in field %s of type %s: %q",
+				f.Name, typ, f.Tag.Get("xml"))
+		}
+	}
+
+	// Use of xmlns without a name is not allowed.
+	if finfo.xmlns != "" && tag == "" {
+		return nil, fmt.Errorf("xml: namespace without name in field %s of type %s: %q",
+			f.Name, typ, f.Tag.Get("xml"))
+	}
+
+	if f.Name == "XMLName" {
+		// The XMLName field records the XML element name. Don't
+		// process it as usual because its name should default to
+		// empty rather than to the field name.
+		finfo.name = tag
+		return finfo, nil
+	}
+
+	if tag == "" {
+		// If the name part of the tag is completely empty, get
+		// default from XMLName of underlying struct if feasible,
+		// or field name otherwise.
+		if xmlname := lookupXMLName(f.Type); xmlname != nil {
+			finfo.xmlns, finfo.name = xmlname.xmlns, xmlname.name
+		} else {
+			finfo.name = f.Name
+		}
+		return finfo, nil
+	}
+
+	if finfo.xmlns == "" && finfo.flags&fAttr == 0 {
+		// If it's an element no namespace specified, get the default
+		// from the XMLName of enclosing struct if possible.
+		if xmlname := lookupXMLName(typ); xmlname != nil {
+			finfo.xmlns = xmlname.xmlns
+		}
+	}
+
+	// Prepare field name and parents.
+	parents := strings.Split(tag, ">")
+	if parents[0] == "" {
+		parents[0] = f.Name
+	}
+	if parents[len(parents)-1] == "" {
+		return nil, fmt.Errorf("xml: trailing '>' in field %s of type %s", f.Name, typ)
+	}
+	finfo.name = parents[len(parents)-1]
+	if len(parents) > 1 {
+		if (finfo.flags & fElement) == 0 {
+			return nil, fmt.Errorf("xml: %s chain not valid with %s flag", tag, strings.Join(tokens[1:], ","))
+		}
+		finfo.parents = parents[:len(parents)-1]
+	}
+
+	// If the field type has an XMLName field, the names must match
+	// so that the behavior of both marshalling and unmarshalling
+	// is straightforward and unambiguous.
+	if finfo.flags&fElement != 0 {
+		ftyp := f.Type
+		xmlname := lookupXMLName(ftyp)
+		if xmlname != nil && xmlname.name != finfo.name {
+			return nil, fmt.Errorf("xml: name %q in tag of %s.%s conflicts with name %q in %s.XMLName",
+				finfo.name, typ, f.Name, xmlname.name, ftyp)
+		}
+	}
+	return finfo, nil
+}
+
+// lookupXMLName returns the fieldInfo for typ's XMLName field
+// in case it exists and has a valid xml field tag, otherwise
+// it returns nil.
+func lookupXMLName(typ reflect.Type) (xmlname *fieldInfo) {
+	for typ.Kind() == reflect.Ptr {
+		typ = typ.Elem()
+	}
+	if typ.Kind() != reflect.Struct {
+		return nil
+	}
+	for i, n := 0, typ.NumField(); i < n; i++ {
+		f := typ.Field(i)
+		if f.Name != "XMLName" {
+			continue
+		}
+		finfo, err := structFieldInfo(typ, &f)
+		if finfo.name != "" && err == nil {
+			return finfo
+		}
+		// Also consider errors as a non-existent field tag
+		// and let getTypeInfo itself report the error.
+		break
+	}
+	return nil
+}
+
+func min(a, b int) int {
+	if a <= b {
+		return a
+	}
+	return b
+}
+
+// addFieldInfo adds finfo to tinfo.fields if there are no
+// conflicts, or if conflicts arise from previous fields that were
+// obtained from deeper embedded structures than finfo. In the latter
+// case, the conflicting entries are dropped.
+// A conflict occurs when the path (parent + name) to a field is
+// itself a prefix of another path, or when two paths match exactly.
+// It is okay for field paths to share a common, shorter prefix.
+func addFieldInfo(typ reflect.Type, tinfo *typeInfo, newf *fieldInfo) error {
+	var conflicts []int
+Loop:
+	// First, figure all conflicts. Most working code will have none.
+	for i := range tinfo.fields {
+		oldf := &tinfo.fields[i]
+		if oldf.flags&fMode != newf.flags&fMode {
+			continue
+		}
+		if oldf.xmlns != "" && newf.xmlns != "" && oldf.xmlns != newf.xmlns {
+			continue
+		}
+		minl := min(len(newf.parents), len(oldf.parents))
+		for p := 0; p < minl; p++ {
+			if oldf.parents[p] != newf.parents[p] {
+				continue Loop
+			}
+		}
+		if len(oldf.parents) > len(newf.parents) {
+			if oldf.parents[len(newf.parents)] == newf.name {
+				conflicts = append(conflicts, i)
+			}
+		} else if len(oldf.parents) < len(newf.parents) {
+			if newf.parents[len(oldf.parents)] == oldf.name {
+				conflicts = append(conflicts, i)
+			}
+		} else {
+			if newf.name == oldf.name {
+				conflicts = append(conflicts, i)
+			}
+		}
+	}
+	// Without conflicts, add the new field and return.
+	if conflicts == nil {
+		tinfo.fields = append(tinfo.fields, *newf)
+		return nil
+	}
+
+	// If any conflict is shallower, ignore the new field.
+	// This matches the Go field resolution on embedding.
+	for _, i := range conflicts {
+		if len(tinfo.fields[i].idx) < len(newf.idx) {
+			return nil
+		}
+	}
+
+	// Otherwise, if any of them is at the same depth level, it's an error.
+	for _, i := range conflicts {
+		oldf := &tinfo.fields[i]
+		if len(oldf.idx) == len(newf.idx) {
+			f1 := typ.FieldByIndex(oldf.idx)
+			f2 := typ.FieldByIndex(newf.idx)
+			return &TagPathError{typ, f1.Name, f1.Tag.Get("xml"), f2.Name, f2.Tag.Get("xml")}
+		}
+	}
+
+	// Otherwise, the new field is shallower, and thus takes precedence,
+	// so drop the conflicting fields from tinfo and append the new one.
+	for c := len(conflicts) - 1; c >= 0; c-- {
+		i := conflicts[c]
+		copy(tinfo.fields[i:], tinfo.fields[i+1:])
+		tinfo.fields = tinfo.fields[:len(tinfo.fields)-1]
+	}
+	tinfo.fields = append(tinfo.fields, *newf)
+	return nil
+}
+
+// A TagPathError represents an error in the unmarshalling process
+// caused by the use of field tags with conflicting paths.
+type TagPathError struct {
+	Struct       reflect.Type
+	Field1, Tag1 string
+	Field2, Tag2 string
+}
+
+func (e *TagPathError) Error() string {
+	return fmt.Sprintf("%s field %q with tag %q conflicts with field %q with tag %q", e.Struct, e.Field1, e.Tag1, e.Field2, e.Tag2)
+}
+
+// value returns v's field value corresponding to finfo.
+// It's equivalent to v.FieldByIndex(finfo.idx), but initializes
+// and dereferences pointers as necessary.
+func (finfo *fieldInfo) value(v reflect.Value) reflect.Value {
+	for i, x := range finfo.idx {
+		if i > 0 {
+			t := v.Type()
+			if t.Kind() == reflect.Ptr && t.Elem().Kind() == reflect.Struct {
+				if v.IsNil() {
+					v.Set(reflect.New(v.Type().Elem()))
+				}
+				v = v.Elem()
+			}
+		}
+		v = v.Field(x)
+	}
+	return v
+}

vendor/golang.org/x/net/webdav/litmus_test_server.go

@@ -0,0 +1,94 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build ignore
+
+/*
+This program is a server for the WebDAV 'litmus' compliance test at
+http://www.webdav.org/neon/litmus/
+To run the test:
+
+go run litmus_test_server.go
+
+and separately, from the downloaded litmus-xxx directory:
+
+make URL=http://localhost:9999/ check
+*/
+package main
+
+import (
+	"flag"
+	"fmt"
+	"log"
+	"net/http"
+	"net/url"
+
+	"golang.org/x/net/webdav"
+)
+
+var port = flag.Int("port", 9999, "server port")
+
+func main() {
+	flag.Parse()
+	log.SetFlags(0)
+	h := &webdav.Handler{
+		FileSystem: webdav.NewMemFS(),
+		LockSystem: webdav.NewMemLS(),
+		Logger: func(r *http.Request, err error) {
+			litmus := r.Header.Get("X-Litmus")
+			if len(litmus) > 19 {
+				litmus = litmus[:16] + "..."
+			}
+
+			switch r.Method {
+			case "COPY", "MOVE":
+				dst := ""
+				if u, err := url.Parse(r.Header.Get("Destination")); err == nil {
+					dst = u.Path
+				}
+				o := r.Header.Get("Overwrite")
+				log.Printf("%-20s%-10s%-30s%-30so=%-2s%v", litmus, r.Method, r.URL.Path, dst, o, err)
+			default:
+				log.Printf("%-20s%-10s%-30s%v", litmus, r.Method, r.URL.Path, err)
+			}
+		},
+	}
+
+	// The next line would normally be:
+	//	http.Handle("/", h)
+	// but we wrap that HTTP handler h to cater for a special case.
+	//
+	// The propfind_invalid2 litmus test case expects an empty namespace prefix
+	// declaration to be an error. The FAQ in the webdav litmus test says:
+	//
+	// "What does the "propfind_invalid2" test check for?...
+	//
+	// If a request was sent with an XML body which included an empty namespace
+	// prefix declaration (xmlns:ns1=""), then the server must reject that with
+	// a "400 Bad Request" response, as it is invalid according to the XML
+	// Namespace specification."
+	//
+	// On the other hand, the Go standard library's encoding/xml package
+	// accepts an empty xmlns namespace, as per the discussion at
+	// https://github.com/golang/go/issues/8068
+	//
+	// Empty namespaces seem disallowed in the second (2006) edition of the XML
+	// standard, but allowed in a later edition. The grammar differs between
+	// http://www.w3.org/TR/2006/REC-xml-names-20060816/#ns-decl and
+	// http://www.w3.org/TR/REC-xml-names/#dt-prefix
+	//
+	// Thus, we assume that the propfind_invalid2 test is obsolete, and
+	// hard-code the 400 Bad Request response that the test expects.
+	http.Handle("/", http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if r.Header.Get("X-Litmus") == "props: 3 (propfind_invalid2)" {
+			http.Error(w, "400 Bad Request", http.StatusBadRequest)
+			return
+		}
+		h.ServeHTTP(w, r)
+	}))
+
+	addr := fmt.Sprintf(":%d", *port)
+	log.Printf("Serving %v", addr)
+	log.Fatal(http.ListenAndServe(addr, nil))
+}

vendor/golang.org/x/net/webdav/lock.go

@@ -0,0 +1,445 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package webdav
+
+import (
+	"container/heap"
+	"errors"
+	"strconv"
+	"strings"
+	"sync"
+	"time"
+)
+
+var (
+	// ErrConfirmationFailed is returned by a LockSystem's Confirm method.
+	ErrConfirmationFailed = errors.New("webdav: confirmation failed")
+	// ErrForbidden is returned by a LockSystem's Unlock method.
+	ErrForbidden = errors.New("webdav: forbidden")
+	// ErrLocked is returned by a LockSystem's Create, Refresh and Unlock methods.
+	ErrLocked = errors.New("webdav: locked")
+	// ErrNoSuchLock is returned by a LockSystem's Refresh and Unlock methods.
+	ErrNoSuchLock = errors.New("webdav: no such lock")
+)
+
+// Condition can match a WebDAV resource, based on a token or ETag.
+// Exactly one of Token and ETag should be non-empty.
+type Condition struct {
+	Not   bool
+	Token string
+	ETag  string
+}
+
+// LockSystem manages access to a collection of named resources. The elements
+// in a lock name are separated by slash ('/', U+002F) characters, regardless
+// of host operating system convention.
+type LockSystem interface {
+	// Confirm confirms that the caller can claim all of the locks specified by
+	// the given conditions, and that holding the union of all of those locks
+	// gives exclusive access to all of the named resources. Up to two resources
+	// can be named. Empty names are ignored.
+	//
+	// Exactly one of release and err will be non-nil. If release is non-nil,
+	// all of the requested locks are held until release is called. Calling
+	// release does not unlock the lock, in the WebDAV UNLOCK sense, but once
+	// Confirm has confirmed that a lock claim is valid, that lock cannot be
+	// Confirmed again until it has been released.
+	//
+	// If Confirm returns ErrConfirmationFailed then the Handler will continue
+	// to try any other set of locks presented (a WebDAV HTTP request can
+	// present more than one set of locks). If it returns any other non-nil
+	// error, the Handler will write a "500 Internal Server Error" HTTP status.
+	Confirm(now time.Time, name0, name1 string, conditions ...Condition) (release func(), err error)
+
+	// Create creates a lock with the given depth, duration, owner and root
+	// (name). The depth will either be negative (meaning infinite) or zero.
+	//
+	// If Create returns ErrLocked then the Handler will write a "423 Locked"
+	// HTTP status. If it returns any other non-nil error, the Handler will
+	// write a "500 Internal Server Error" HTTP status.
+	//
+	// See http://www.webdav.org/specs/rfc4918.html#rfc.section.9.10.6 for
+	// when to use each error.
+	//
+	// The token returned identifies the created lock. It should be an absolute
+	// URI as defined by RFC 3986, Section 4.3. In particular, it should not
+	// contain whitespace.
+	Create(now time.Time, details LockDetails) (token string, err error)
+
+	// Refresh refreshes the lock with the given token.
+	//
+	// If Refresh returns ErrLocked then the Handler will write a "423 Locked"
+	// HTTP Status. If Refresh returns ErrNoSuchLock then the Handler will write
+	// a "412 Precondition Failed" HTTP Status. If it returns any other non-nil
+	// error, the Handler will write a "500 Internal Server Error" HTTP status.
+	//
+	// See http://www.webdav.org/specs/rfc4918.html#rfc.section.9.10.6 for
+	// when to use each error.
+	Refresh(now time.Time, token string, duration time.Duration) (LockDetails, error)
+
+	// Unlock unlocks the lock with the given token.
+	//
+	// If Unlock returns ErrForbidden then the Handler will write a "403
+	// Forbidden" HTTP Status. If Unlock returns ErrLocked then the Handler
+	// will write a "423 Locked" HTTP status. If Unlock returns ErrNoSuchLock
+	// then the Handler will write a "409 Conflict" HTTP Status. If it returns
+	// any other non-nil error, the Handler will write a "500 Internal Server
+	// Error" HTTP status.
+	//
+	// See http://www.webdav.org/specs/rfc4918.html#rfc.section.9.11.1 for
+	// when to use each error.
+	Unlock(now time.Time, token string) error
+}
+
+// LockDetails are a lock's metadata.
+type LockDetails struct {
+	// Root is the root resource name being locked. For a zero-depth lock, the
+	// root is the only resource being locked.
+	Root string
+	// Duration is the lock timeout. A negative duration means infinite.
+	Duration time.Duration
+	// OwnerXML is the verbatim <owner> XML given in a LOCK HTTP request.
+	//
+	// TODO: does the "verbatim" nature play well with XML namespaces?
+	// Does the OwnerXML field need to have more structure? See
+	// https://codereview.appspot.com/175140043/#msg2
+	OwnerXML string
+	// ZeroDepth is whether the lock has zero depth. If it does not have zero
+	// depth, it has infinite depth.
+	ZeroDepth bool
+}
+
+// NewMemLS returns a new in-memory LockSystem.
+func NewMemLS() LockSystem {
+	return &memLS{
+		byName:  make(map[string]*memLSNode),
+		byToken: make(map[string]*memLSNode),
+		gen:     uint64(time.Now().Unix()),
+	}
+}
+
+type memLS struct {
+	mu      sync.Mutex
+	byName  map[string]*memLSNode
+	byToken map[string]*memLSNode
+	gen     uint64
+	// byExpiry only contains those nodes whose LockDetails have a finite
+	// Duration and are yet to expire.
+	byExpiry byExpiry
+}
+
+func (m *memLS) nextToken() string {
+	m.gen++
+	return strconv.FormatUint(m.gen, 10)
+}
+
+func (m *memLS) collectExpiredNodes(now time.Time) {
+	for len(m.byExpiry) > 0 {
+		if now.Before(m.byExpiry[0].expiry) {
+			break
+		}
+		m.remove(m.byExpiry[0])
+	}
+}
+
+func (m *memLS) Confirm(now time.Time, name0, name1 string, conditions ...Condition) (func(), error) {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+	m.collectExpiredNodes(now)
+
+	var n0, n1 *memLSNode
+	if name0 != "" {
+		if n0 = m.lookup(slashClean(name0), conditions...); n0 == nil {
+			return nil, ErrConfirmationFailed
+		}
+	}
+	if name1 != "" {
+		if n1 = m.lookup(slashClean(name1), conditions...); n1 == nil {
+			return nil, ErrConfirmationFailed
+		}
+	}
+
+	// Don't hold the same node twice.
+	if n1 == n0 {
+		n1 = nil
+	}
+
+	if n0 != nil {
+		m.hold(n0)
+	}
+	if n1 != nil {
+		m.hold(n1)
+	}
+	return func() {
+		m.mu.Lock()
+		defer m.mu.Unlock()
+		if n1 != nil {
+			m.unhold(n1)
+		}
+		if n0 != nil {
+			m.unhold(n0)
+		}
+	}, nil
+}
+
+// lookup returns the node n that locks the named resource, provided that n
+// matches at least one of the given conditions and that lock isn't held by
+// another party. Otherwise, it returns nil.
+//
+// n may be a parent of the named resource, if n is an infinite depth lock.
+func (m *memLS) lookup(name string, conditions ...Condition) (n *memLSNode) {
+	// TODO: support Condition.Not and Condition.ETag.
+	for _, c := range conditions {
+		n = m.byToken[c.Token]
+		if n == nil || n.held {
+			continue
+		}
+		if name == n.details.Root {
+			return n
+		}
+		if n.details.ZeroDepth {
+			continue
+		}
+		if n.details.Root == "/" || strings.HasPrefix(name, n.details.Root+"/") {
+			return n
+		}
+	}
+	return nil
+}
+
+func (m *memLS) hold(n *memLSNode) {
+	if n.held {
+		panic("webdav: memLS inconsistent held state")
+	}
+	n.held = true
+	if n.details.Duration >= 0 && n.byExpiryIndex >= 0 {
+		heap.Remove(&m.byExpiry, n.byExpiryIndex)
+	}
+}
+
+func (m *memLS) unhold(n *memLSNode) {
+	if !n.held {
+		panic("webdav: memLS inconsistent held state")
+	}
+	n.held = false
+	if n.details.Duration >= 0 {
+		heap.Push(&m.byExpiry, n)
+	}
+}
+
+func (m *memLS) Create(now time.Time, details LockDetails) (string, error) {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+	m.collectExpiredNodes(now)
+	details.Root = slashClean(details.Root)
+
+	if !m.canCreate(details.Root, details.ZeroDepth) {
+		return "", ErrLocked
+	}
+	n := m.create(details.Root)
+	n.token = m.nextToken()
+	m.byToken[n.token] = n
+	n.details = details
+	if n.details.Duration >= 0 {
+		n.expiry = now.Add(n.details.Duration)
+		heap.Push(&m.byExpiry, n)
+	}
+	return n.token, nil
+}
+
+func (m *memLS) Refresh(now time.Time, token string, duration time.Duration) (LockDetails, error) {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+	m.collectExpiredNodes(now)
+
+	n := m.byToken[token]
+	if n == nil {
+		return LockDetails{}, ErrNoSuchLock
+	}
+	if n.held {
+		return LockDetails{}, ErrLocked
+	}
+	if n.byExpiryIndex >= 0 {
+		heap.Remove(&m.byExpiry, n.byExpiryIndex)
+	}
+	n.details.Duration = duration
+	if n.details.Duration >= 0 {
+		n.expiry = now.Add(n.details.Duration)
+		heap.Push(&m.byExpiry, n)
+	}
+	return n.details, nil
+}
+
+func (m *memLS) Unlock(now time.Time, token string) error {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+	m.collectExpiredNodes(now)
+
+	n := m.byToken[token]
+	if n == nil {
+		return ErrNoSuchLock
+	}
+	if n.held {
+		return ErrLocked
+	}
+	m.remove(n)
+	return nil
+}
+
+func (m *memLS) canCreate(name string, zeroDepth bool) bool {
+	return walkToRoot(name, func(name0 string, first bool) bool {
+		n := m.byName[name0]
+		if n == nil {
+			return true
+		}
+		if first {
+			if n.token != "" {
+				// The target node is already locked.
+				return false
+			}
+			if !zeroDepth {
+				// The requested lock depth is infinite, and the fact that n exists
+				// (n != nil) means that a descendent of the target node is locked.
+				return false
+			}
+		} else if n.token != "" && !n.details.ZeroDepth {
+			// An ancestor of the target node is locked with infinite depth.
+			return false
+		}
+		return true
+	})
+}
+
+func (m *memLS) create(name string) (ret *memLSNode) {
+	walkToRoot(name, func(name0 string, first bool) bool {
+		n := m.byName[name0]
+		if n == nil {
+			n = &memLSNode{
+				details: LockDetails{
+					Root: name0,
+				},
+				byExpiryIndex: -1,
+			}
+			m.byName[name0] = n
+		}
+		n.refCount++
+		if first {
+			ret = n
+		}
+		return true
+	})
+	return ret
+}
+
+func (m *memLS) remove(n *memLSNode) {
+	delete(m.byToken, n.token)
+	n.token = ""
+	walkToRoot(n.details.Root, func(name0 string, first bool) bool {
+		x := m.byName[name0]
+		x.refCount--
+		if x.refCount == 0 {
+			delete(m.byName, name0)
+		}
+		return true
+	})
+	if n.byExpiryIndex >= 0 {
+		heap.Remove(&m.byExpiry, n.byExpiryIndex)
+	}
+}
+
+func walkToRoot(name string, f func(name0 string, first bool) bool) bool {
+	for first := true; ; first = false {
+		if !f(name, first) {
+			return false
+		}
+		if name == "/" {
+			break
+		}
+		name = name[:strings.LastIndex(name, "/")]
+		if name == "" {
+			name = "/"
+		}
+	}
+	return true
+}
+
+type memLSNode struct {
+	// details are the lock metadata. Even if this node's name is not explicitly locked,
+	// details.Root will still equal the node's name.
+	details LockDetails
+	// token is the unique identifier for this node's lock. An empty token means that
+	// this node is not explicitly locked.
+	token string
+	// refCount is the number of self-or-descendent nodes that are explicitly locked.
+	refCount int
+	// expiry is when this node's lock expires.
+	expiry time.Time
+	// byExpiryIndex is the index of this node in memLS.byExpiry. It is -1
+	// if this node does not expire, or has expired.
+	byExpiryIndex int
+	// held is whether this node's lock is actively held by a Confirm call.
+	held bool
+}
+
+type byExpiry []*memLSNode
+
+func (b *byExpiry) Len() int {
+	return len(*b)
+}
+
+func (b *byExpiry) Less(i, j int) bool {
+	return (*b)[i].expiry.Before((*b)[j].expiry)
+}
+
+func (b *byExpiry) Swap(i, j int) {
+	(*b)[i], (*b)[j] = (*b)[j], (*b)[i]
+	(*b)[i].byExpiryIndex = i
+	(*b)[j].byExpiryIndex = j
+}
+
+func (b *byExpiry) Push(x interface{}) {
+	n := x.(*memLSNode)
+	n.byExpiryIndex = len(*b)
+	*b = append(*b, n)
+}
+
+func (b *byExpiry) Pop() interface{} {
+	i := len(*b) - 1
+	n := (*b)[i]
+	(*b)[i] = nil
+	n.byExpiryIndex = -1
+	*b = (*b)[:i]
+	return n
+}
+
+const infiniteTimeout = -1
+
+// parseTimeout parses the Timeout HTTP header, as per section 10.7. If s is
+// empty, an infiniteTimeout is returned.
+func parseTimeout(s string) (time.Duration, error) {
+	if s == "" {
+		return infiniteTimeout, nil
+	}
+	if i := strings.IndexByte(s, ','); i >= 0 {
+		s = s[:i]
+	}
+	s = strings.TrimSpace(s)
+	if s == "Infinite" {
+		return infiniteTimeout, nil
+	}
+	const pre = "Second-"
+	if !strings.HasPrefix(s, pre) {
+		return 0, errInvalidTimeout
+	}
+	s = s[len(pre):]
+	if s == "" || s[0] < '0' || '9' < s[0] {
+		return 0, errInvalidTimeout
+	}
+	n, err := strconv.ParseInt(s, 10, 64)
+	if err != nil || 1<<32-1 < n {
+		return 0, errInvalidTimeout
+	}
+	return time.Duration(n) * time.Second, nil
+}

vendor/golang.org/x/net/webdav/prop.go

@@ -0,0 +1,418 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package webdav
+
+import (
+	"bytes"
+	"encoding/xml"
+	"fmt"
+	"io"
+	"mime"
+	"net/http"
+	"os"
+	"path/filepath"
+	"strconv"
+
+	"golang.org/x/net/context"
+)
+
+// Proppatch describes a property update instruction as defined in RFC 4918.
+// See http://www.webdav.org/specs/rfc4918.html#METHOD_PROPPATCH
+type Proppatch struct {
+	// Remove specifies whether this patch removes properties. If it does not
+	// remove them, it sets them.
+	Remove bool
+	// Props contains the properties to be set or removed.
+	Props []Property
+}
+
+// Propstat describes a XML propstat element as defined in RFC 4918.
+// See http://www.webdav.org/specs/rfc4918.html#ELEMENT_propstat
+type Propstat struct {
+	// Props contains the properties for which Status applies.
+	Props []Property
+
+	// Status defines the HTTP status code of the properties in Prop.
+	// Allowed values include, but are not limited to the WebDAV status
+	// code extensions for HTTP/1.1.
+	// http://www.webdav.org/specs/rfc4918.html#status.code.extensions.to.http11
+	Status int
+
+	// XMLError contains the XML representation of the optional error element.
+	// XML content within this field must not rely on any predefined
+	// namespace declarations or prefixes. If empty, the XML error element
+	// is omitted.
+	XMLError string
+
+	// ResponseDescription contains the contents of the optional
+	// responsedescription field. If empty, the XML element is omitted.
+	ResponseDescription string
+}
+
+// makePropstats returns a slice containing those of x and y whose Props slice
+// is non-empty. If both are empty, it returns a slice containing an otherwise
+// zero Propstat whose HTTP status code is 200 OK.
+func makePropstats(x, y Propstat) []Propstat {
+	pstats := make([]Propstat, 0, 2)
+	if len(x.Props) != 0 {
+		pstats = append(pstats, x)
+	}
+	if len(y.Props) != 0 {
+		pstats = append(pstats, y)
+	}
+	if len(pstats) == 0 {
+		pstats = append(pstats, Propstat{
+			Status: http.StatusOK,
+		})
+	}
+	return pstats
+}
+
+// DeadPropsHolder holds the dead properties of a resource.
+//
+// Dead properties are those properties that are explicitly defined. In
+// comparison, live properties, such as DAV:getcontentlength, are implicitly
+// defined by the underlying resource, and cannot be explicitly overridden or
+// removed. See the Terminology section of
+// http://www.webdav.org/specs/rfc4918.html#rfc.section.3
+//
+// There is a whitelist of the names of live properties. This package handles
+// all live properties, and will only pass non-whitelisted names to the Patch
+// method of DeadPropsHolder implementations.
+type DeadPropsHolder interface {
+	// DeadProps returns a copy of the dead properties held.
+	DeadProps() (map[xml.Name]Property, error)
+
+	// Patch patches the dead properties held.
+	//
+	// Patching is atomic; either all or no patches succeed. It returns (nil,
+	// non-nil) if an internal server error occurred, otherwise the Propstats
+	// collectively contain one Property for each proposed patch Property. If
+	// all patches succeed, Patch returns a slice of length one and a Propstat
+	// element with a 200 OK HTTP status code. If none succeed, for reasons
+	// other than an internal server error, no Propstat has status 200 OK.
+	//
+	// For more details on when various HTTP status codes apply, see
+	// http://www.webdav.org/specs/rfc4918.html#PROPPATCH-status
+	Patch([]Proppatch) ([]Propstat, error)
+}
+
+// liveProps contains all supported, protected DAV: properties.
+var liveProps = map[xml.Name]struct {
+	// findFn implements the propfind function of this property. If nil,
+	// it indicates a hidden property.
+	findFn func(context.Context, FileSystem, LockSystem, string, os.FileInfo) (string, error)
+	// dir is true if the property applies to directories.
+	dir bool
+}{
+	{Space: "DAV:", Local: "resourcetype"}: {
+		findFn: findResourceType,
+		dir:    true,
+	},
+	{Space: "DAV:", Local: "displayname"}: {
+		findFn: findDisplayName,
+		dir:    true,
+	},
+	{Space: "DAV:", Local: "getcontentlength"}: {
+		findFn: findContentLength,
+		dir:    false,
+	},
+	{Space: "DAV:", Local: "getlastmodified"}: {
+		findFn: findLastModified,
+		// http://webdav.org/specs/rfc4918.html#PROPERTY_getlastmodified
+		// suggests that getlastmodified should only apply to GETable
+		// resources, and this package does not support GET on directories.
+		//
+		// Nonetheless, some WebDAV clients expect child directories to be
+		// sortable by getlastmodified date, so this value is true, not false.
+		// See golang.org/issue/15334.
+		dir: true,
+	},
+	{Space: "DAV:", Local: "creationdate"}: {
+		findFn: nil,
+		dir:    false,
+	},
+	{Space: "DAV:", Local: "getcontentlanguage"}: {
+		findFn: nil,
+		dir:    false,
+	},
+	{Space: "DAV:", Local: "getcontenttype"}: {
+		findFn: findContentType,
+		dir:    false,
+	},
+	{Space: "DAV:", Local: "getetag"}: {
+		findFn: findETag,
+		// findETag implements ETag as the concatenated hex values of a file's
+		// modification time and size. This is not a reliable synchronization
+		// mechanism for directories, so we do not advertise getetag for DAV
+		// collections.
+		dir: false,
+	},
+
+	// TODO: The lockdiscovery property requires LockSystem to list the
+	// active locks on a resource.
+	{Space: "DAV:", Local: "lockdiscovery"}: {},
+	{Space: "DAV:", Local: "supportedlock"}: {
+		findFn: findSupportedLock,
+		dir:    true,
+	},
+}
+
+// TODO(nigeltao) merge props and allprop?
+
+// Props returns the status of the properties named pnames for resource name.
+//
+// Each Propstat has a unique status and each property name will only be part
+// of one Propstat element.
+func props(ctx context.Context, fs FileSystem, ls LockSystem, name string, pnames []xml.Name) ([]Propstat, error) {
+	f, err := fs.OpenFile(ctx, name, os.O_RDONLY, 0)
+	if err != nil {
+		return nil, err
+	}
+	defer f.Close()
+	fi, err := f.Stat()
+	if err != nil {
+		return nil, err
+	}
+	isDir := fi.IsDir()
+
+	var deadProps map[xml.Name]Property
+	if dph, ok := f.(DeadPropsHolder); ok {
+		deadProps, err = dph.DeadProps()
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	pstatOK := Propstat{Status: http.StatusOK}
+	pstatNotFound := Propstat{Status: http.StatusNotFound}
+	for _, pn := range pnames {
+		// If this file has dead properties, check if they contain pn.
+		if dp, ok := deadProps[pn]; ok {
+			pstatOK.Props = append(pstatOK.Props, dp)
+			continue
+		}
+		// Otherwise, it must either be a live property or we don't know it.
+		if prop := liveProps[pn]; prop.findFn != nil && (prop.dir || !isDir) {
+			innerXML, err := prop.findFn(ctx, fs, ls, name, fi)
+			if err != nil {
+				return nil, err
+			}
+			pstatOK.Props = append(pstatOK.Props, Property{
+				XMLName:  pn,
+				InnerXML: []byte(innerXML),
+			})
+		} else {
+			pstatNotFound.Props = append(pstatNotFound.Props, Property{
+				XMLName: pn,
+			})
+		}
+	}
+	return makePropstats(pstatOK, pstatNotFound), nil
+}
+
+// Propnames returns the property names defined for resource name.
+func propnames(ctx context.Context, fs FileSystem, ls LockSystem, name string) ([]xml.Name, error) {
+	f, err := fs.OpenFile(ctx, name, os.O_RDONLY, 0)
+	if err != nil {
+		return nil, err
+	}
+	defer f.Close()
+	fi, err := f.Stat()
+	if err != nil {
+		return nil, err
+	}
+	isDir := fi.IsDir()
+
+	var deadProps map[xml.Name]Property
+	if dph, ok := f.(DeadPropsHolder); ok {
+		deadProps, err = dph.DeadProps()
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	pnames := make([]xml.Name, 0, len(liveProps)+len(deadProps))
+	for pn, prop := range liveProps {
+		if prop.findFn != nil && (prop.dir || !isDir) {
+			pnames = append(pnames, pn)
+		}
+	}
+	for pn := range deadProps {
+		pnames = append(pnames, pn)
+	}
+	return pnames, nil
+}
+
+// Allprop returns the properties defined for resource name and the properties
+// named in include.
+//
+// Note that RFC 4918 defines 'allprop' to return the DAV: properties defined
+// within the RFC plus dead properties. Other live properties should only be
+// returned if they are named in 'include'.
+//
+// See http://www.webdav.org/specs/rfc4918.html#METHOD_PROPFIND
+func allprop(ctx context.Context, fs FileSystem, ls LockSystem, name string, include []xml.Name) ([]Propstat, error) {
+	pnames, err := propnames(ctx, fs, ls, name)
+	if err != nil {
+		return nil, err
+	}
+	// Add names from include if they are not already covered in pnames.
+	nameset := make(map[xml.Name]bool)
+	for _, pn := range pnames {
+		nameset[pn] = true
+	}
+	for _, pn := range include {
+		if !nameset[pn] {
+			pnames = append(pnames, pn)
+		}
+	}
+	return props(ctx, fs, ls, name, pnames)
+}
+
+// Patch patches the properties of resource name. The return values are
+// constrained in the same manner as DeadPropsHolder.Patch.
+func patch(ctx context.Context, fs FileSystem, ls LockSystem, name string, patches []Proppatch) ([]Propstat, error) {
+	conflict := false
+loop:
+	for _, patch := range patches {
+		for _, p := range patch.Props {
+			if _, ok := liveProps[p.XMLName]; ok {
+				conflict = true
+				break loop
+			}
+		}
+	}
+	if conflict {
+		pstatForbidden := Propstat{
+			Status:   http.StatusForbidden,
+			XMLError: `<D:cannot-modify-protected-property xmlns:D="DAV:"/>`,
+		}
+		pstatFailedDep := Propstat{
+			Status: StatusFailedDependency,
+		}
+		for _, patch := range patches {
+			for _, p := range patch.Props {
+				if _, ok := liveProps[p.XMLName]; ok {
+					pstatForbidden.Props = append(pstatForbidden.Props, Property{XMLName: p.XMLName})
+				} else {
+					pstatFailedDep.Props = append(pstatFailedDep.Props, Property{XMLName: p.XMLName})
+				}
+			}
+		}
+		return makePropstats(pstatForbidden, pstatFailedDep), nil
+	}
+
+	f, err := fs.OpenFile(ctx, name, os.O_RDWR, 0)
+	if err != nil {
+		return nil, err
+	}
+	defer f.Close()
+	if dph, ok := f.(DeadPropsHolder); ok {
+		ret, err := dph.Patch(patches)
+		if err != nil {
+			return nil, err
+		}
+		// http://www.webdav.org/specs/rfc4918.html#ELEMENT_propstat says that
+		// "The contents of the prop XML element must only list the names of
+		// properties to which the result in the status element applies."
+		for _, pstat := range ret {
+			for i, p := range pstat.Props {
+				pstat.Props[i] = Property{XMLName: p.XMLName}
+			}
+		}
+		return ret, nil
+	}
+	// The file doesn't implement the optional DeadPropsHolder interface, so
+	// all patches are forbidden.
+	pstat := Propstat{Status: http.StatusForbidden}
+	for _, patch := range patches {
+		for _, p := range patch.Props {
+			pstat.Props = append(pstat.Props, Property{XMLName: p.XMLName})
+		}
+	}
+	return []Propstat{pstat}, nil
+}
+
+func escapeXML(s string) string {
+	for i := 0; i < len(s); i++ {
+		// As an optimization, if s contains only ASCII letters, digits or a
+		// few special characters, the escaped value is s itself and we don't
+		// need to allocate a buffer and convert between string and []byte.
+		switch c := s[i]; {
+		case c == ' ' || c == '_' ||
+			('+' <= c && c <= '9') || // Digits as well as + , - . and /
+			('A' <= c && c <= 'Z') ||
+			('a' <= c && c <= 'z'):
+			continue
+		}
+		// Otherwise, go through the full escaping process.
+		var buf bytes.Buffer
+		xml.EscapeText(&buf, []byte(s))
+		return buf.String()
+	}
+	return s
+}
+
+func findResourceType(ctx context.Context, fs FileSystem, ls LockSystem, name string, fi os.FileInfo) (string, error) {
+	if fi.IsDir() {
+		return `<D:collection xmlns:D="DAV:"/>`, nil
+	}
+	return "", nil
+}
+
+func findDisplayName(ctx context.Context, fs FileSystem, ls LockSystem, name string, fi os.FileInfo) (string, error) {
+	if slashClean(name) == "/" {
+		// Hide the real name of a possibly prefixed root directory.
+		return "", nil
+	}
+	return escapeXML(fi.Name()), nil
+}
+
+func findContentLength(ctx context.Context, fs FileSystem, ls LockSystem, name string, fi os.FileInfo) (string, error) {
+	return strconv.FormatInt(fi.Size(), 10), nil
+}
+
+func findLastModified(ctx context.Context, fs FileSystem, ls LockSystem, name string, fi os.FileInfo) (string, error) {
+	return fi.ModTime().Format(http.TimeFormat), nil
+}
+
+func findContentType(ctx context.Context, fs FileSystem, ls LockSystem, name string, fi os.FileInfo) (string, error) {
+	f, err := fs.OpenFile(ctx, name, os.O_RDONLY, 0)
+	if err != nil {
+		return "", err
+	}
+	defer f.Close()
+	// This implementation is based on serveContent's code in the standard net/http package.
+	ctype := mime.TypeByExtension(filepath.Ext(name))
+	if ctype != "" {
+		return ctype, nil
+	}
+	// Read a chunk to decide between utf-8 text and binary.
+	var buf [512]byte
+	n, err := io.ReadFull(f, buf[:])
+	if err != nil && err != io.EOF && err != io.ErrUnexpectedEOF {
+		return "", err
+	}
+	ctype = http.DetectContentType(buf[:n])
+	// Rewind file.
+	_, err = f.Seek(0, os.SEEK_SET)
+	return ctype, err
+}
+
+func findETag(ctx context.Context, fs FileSystem, ls LockSystem, name string, fi os.FileInfo) (string, error) {
+	// The Apache http 2.4 web server by default concatenates the
+	// modification time and size of a file. We replicate the heuristic
+	// with nanosecond granularity.
+	return fmt.Sprintf(`"%x%x"`, fi.ModTime().UnixNano(), fi.Size()), nil
+}
+
+func findSupportedLock(ctx context.Context, fs FileSystem, ls LockSystem, name string, fi os.FileInfo) (string, error) {
+	return `` +
+		`<D:lockentry xmlns:D="DAV:">` +
+		`<D:lockscope><D:exclusive/></D:lockscope>` +
+		`<D:locktype><D:write/></D:locktype>` +
+		`</D:lockentry>`, nil
+}

vendor/golang.org/x/net/webdav/webdav.go

@@ -0,0 +1,702 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package webdav provides a WebDAV server implementation.
+package webdav // import "golang.org/x/net/webdav"
+
+import (
+	"errors"
+	"fmt"
+	"io"
+	"net/http"
+	"net/url"
+	"os"
+	"path"
+	"strings"
+	"time"
+)
+
+type Handler struct {
+	// Prefix is the URL path prefix to strip from WebDAV resource paths.
+	Prefix string
+	// FileSystem is the virtual file system.
+	FileSystem FileSystem
+	// LockSystem is the lock management system.
+	LockSystem LockSystem
+	// Logger is an optional error logger. If non-nil, it will be called
+	// for all HTTP requests.
+	Logger func(*http.Request, error)
+}
+
+func (h *Handler) stripPrefix(p string) (string, int, error) {
+	if h.Prefix == "" {
+		return p, http.StatusOK, nil
+	}
+	if r := strings.TrimPrefix(p, h.Prefix); len(r) < len(p) {
+		return r, http.StatusOK, nil
+	}
+	return p, http.StatusNotFound, errPrefixMismatch
+}
+
+func (h *Handler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	status, err := http.StatusBadRequest, errUnsupportedMethod
+	if h.FileSystem == nil {
+		status, err = http.StatusInternalServerError, errNoFileSystem
+	} else if h.LockSystem == nil {
+		status, err = http.StatusInternalServerError, errNoLockSystem
+	} else {
+		switch r.Method {
+		case "OPTIONS":
+			status, err = h.handleOptions(w, r)
+		case "GET", "HEAD", "POST":
+			status, err = h.handleGetHeadPost(w, r)
+		case "DELETE":
+			status, err = h.handleDelete(w, r)
+		case "PUT":
+			status, err = h.handlePut(w, r)
+		case "MKCOL":
+			status, err = h.handleMkcol(w, r)
+		case "COPY", "MOVE":
+			status, err = h.handleCopyMove(w, r)
+		case "LOCK":
+			status, err = h.handleLock(w, r)
+		case "UNLOCK":
+			status, err = h.handleUnlock(w, r)
+		case "PROPFIND":
+			status, err = h.handlePropfind(w, r)
+		case "PROPPATCH":
+			status, err = h.handleProppatch(w, r)
+		}
+	}
+
+	if status != 0 {
+		w.WriteHeader(status)
+		if status != http.StatusNoContent {
+			w.Write([]byte(StatusText(status)))
+		}
+	}
+	if h.Logger != nil {
+		h.Logger(r, err)
+	}
+}
+
+func (h *Handler) lock(now time.Time, root string) (token string, status int, err error) {
+	token, err = h.LockSystem.Create(now, LockDetails{
+		Root:      root,
+		Duration:  infiniteTimeout,
+		ZeroDepth: true,
+	})
+	if err != nil {
+		if err == ErrLocked {
+			return "", StatusLocked, err
+		}
+		return "", http.StatusInternalServerError, err
+	}
+	return token, 0, nil
+}
+
+func (h *Handler) confirmLocks(r *http.Request, src, dst string) (release func(), status int, err error) {
+	hdr := r.Header.Get("If")
+	if hdr == "" {
+		// An empty If header means that the client hasn't previously created locks.
+		// Even if this client doesn't care about locks, we still need to check that
+		// the resources aren't locked by another client, so we create temporary
+		// locks that would conflict with another client's locks. These temporary
+		// locks are unlocked at the end of the HTTP request.
+		now, srcToken, dstToken := time.Now(), "", ""
+		if src != "" {
+			srcToken, status, err = h.lock(now, src)
+			if err != nil {
+				return nil, status, err
+			}
+		}
+		if dst != "" {
+			dstToken, status, err = h.lock(now, dst)
+			if err != nil {
+				if srcToken != "" {
+					h.LockSystem.Unlock(now, srcToken)
+				}
+				return nil, status, err
+			}
+		}
+
+		return func() {
+			if dstToken != "" {
+				h.LockSystem.Unlock(now, dstToken)
+			}
+			if srcToken != "" {
+				h.LockSystem.Unlock(now, srcToken)
+			}
+		}, 0, nil
+	}
+
+	ih, ok := parseIfHeader(hdr)
+	if !ok {
+		return nil, http.StatusBadRequest, errInvalidIfHeader
+	}
+	// ih is a disjunction (OR) of ifLists, so any ifList will do.
+	for _, l := range ih.lists {
+		lsrc := l.resourceTag
+		if lsrc == "" {
+			lsrc = src
+		} else {
+			u, err := url.Parse(lsrc)
+			if err != nil {
+				continue
+			}
+			if u.Host != r.Host {
+				continue
+			}
+			lsrc, status, err = h.stripPrefix(u.Path)
+			if err != nil {
+				return nil, status, err
+			}
+		}
+		release, err = h.LockSystem.Confirm(time.Now(), lsrc, dst, l.conditions...)
+		if err == ErrConfirmationFailed {
+			continue
+		}
+		if err != nil {
+			return nil, http.StatusInternalServerError, err
+		}
+		return release, 0, nil
+	}
+	// Section 10.4.1 says that "If this header is evaluated and all state lists
+	// fail, then the request must fail with a 412 (Precondition Failed) status."
+	// We follow the spec even though the cond_put_corrupt_token test case from
+	// the litmus test warns on seeing a 412 instead of a 423 (Locked).
+	return nil, http.StatusPreconditionFailed, ErrLocked
+}
+
+func (h *Handler) handleOptions(w http.ResponseWriter, r *http.Request) (status int, err error) {
+	reqPath, status, err := h.stripPrefix(r.URL.Path)
+	if err != nil {
+		return status, err
+	}
+	ctx := getContext(r)
+	allow := "OPTIONS, LOCK, PUT, MKCOL"
+	if fi, err := h.FileSystem.Stat(ctx, reqPath); err == nil {
+		if fi.IsDir() {
+			allow = "OPTIONS, LOCK, DELETE, PROPPATCH, COPY, MOVE, UNLOCK, PROPFIND"
+		} else {
+			allow = "OPTIONS, LOCK, GET, HEAD, POST, DELETE, PROPPATCH, COPY, MOVE, UNLOCK, PROPFIND, PUT"
+		}
+	}
+	w.Header().Set("Allow", allow)
+	// http://www.webdav.org/specs/rfc4918.html#dav.compliance.classes
+	w.Header().Set("DAV", "1, 2")
+	// http://msdn.microsoft.com/en-au/library/cc250217.aspx
+	w.Header().Set("MS-Author-Via", "DAV")
+	return 0, nil
+}
+
+func (h *Handler) handleGetHeadPost(w http.ResponseWriter, r *http.Request) (status int, err error) {
+	reqPath, status, err := h.stripPrefix(r.URL.Path)
+	if err != nil {
+		return status, err
+	}
+	// TODO: check locks for read-only access??
+	ctx := getContext(r)
+	f, err := h.FileSystem.OpenFile(ctx, reqPath, os.O_RDONLY, 0)
+	if err != nil {
+		return http.StatusNotFound, err
+	}
+	defer f.Close()
+	fi, err := f.Stat()
+	if err != nil {
+		return http.StatusNotFound, err
+	}
+	if fi.IsDir() {
+		return http.StatusMethodNotAllowed, nil
+	}
+	etag, err := findETag(ctx, h.FileSystem, h.LockSystem, reqPath, fi)
+	if err != nil {
+		return http.StatusInternalServerError, err
+	}
+	w.Header().Set("ETag", etag)
+	// Let ServeContent determine the Content-Type header.
+	http.ServeContent(w, r, reqPath, fi.ModTime(), f)
+	return 0, nil
+}
+
+func (h *Handler) handleDelete(w http.ResponseWriter, r *http.Request) (status int, err error) {
+	reqPath, status, err := h.stripPrefix(r.URL.Path)
+	if err != nil {
+		return status, err
+	}
+	release, status, err := h.confirmLocks(r, reqPath, "")
+	if err != nil {
+		return status, err
+	}
+	defer release()
+
+	ctx := getContext(r)
+
+	// TODO: return MultiStatus where appropriate.
+
+	// "godoc os RemoveAll" says that "If the path does not exist, RemoveAll
+	// returns nil (no error)." WebDAV semantics are that it should return a
+	// "404 Not Found". We therefore have to Stat before we RemoveAll.
+	if _, err := h.FileSystem.Stat(ctx, reqPath); err != nil {
+		if os.IsNotExist(err) {
+			return http.StatusNotFound, err
+		}
+		return http.StatusMethodNotAllowed, err
+	}
+	if err := h.FileSystem.RemoveAll(ctx, reqPath); err != nil {
+		return http.StatusMethodNotAllowed, err
+	}
+	return http.StatusNoContent, nil
+}
+
+func (h *Handler) handlePut(w http.ResponseWriter, r *http.Request) (status int, err error) {
+	reqPath, status, err := h.stripPrefix(r.URL.Path)
+	if err != nil {
+		return status, err
+	}
+	release, status, err := h.confirmLocks(r, reqPath, "")
+	if err != nil {
+		return status, err
+	}
+	defer release()
+	// TODO(rost): Support the If-Match, If-None-Match headers? See bradfitz'
+	// comments in http.checkEtag.
+	ctx := getContext(r)
+
+	f, err := h.FileSystem.OpenFile(ctx, reqPath, os.O_RDWR|os.O_CREATE|os.O_TRUNC, 0666)
+	if err != nil {
+		return http.StatusNotFound, err
+	}
+	_, copyErr := io.Copy(f, r.Body)
+	fi, statErr := f.Stat()
+	closeErr := f.Close()
+	// TODO(rost): Returning 405 Method Not Allowed might not be appropriate.
+	if copyErr != nil {
+		return http.StatusMethodNotAllowed, copyErr
+	}
+	if statErr != nil {
+		return http.StatusMethodNotAllowed, statErr
+	}
+	if closeErr != nil {
+		return http.StatusMethodNotAllowed, closeErr
+	}
+	etag, err := findETag(ctx, h.FileSystem, h.LockSystem, reqPath, fi)
+	if err != nil {
+		return http.StatusInternalServerError, err
+	}
+	w.Header().Set("ETag", etag)
+	return http.StatusCreated, nil
+}
+
+func (h *Handler) handleMkcol(w http.ResponseWriter, r *http.Request) (status int, err error) {
+	reqPath, status, err := h.stripPrefix(r.URL.Path)
+	if err != nil {
+		return status, err
+	}
+	release, status, err := h.confirmLocks(r, reqPath, "")
+	if err != nil {
+		return status, err
+	}
+	defer release()
+
+	ctx := getContext(r)
+
+	if r.ContentLength > 0 {
+		return http.StatusUnsupportedMediaType, nil
+	}
+	if err := h.FileSystem.Mkdir(ctx, reqPath, 0777); err != nil {
+		if os.IsNotExist(err) {
+			return http.StatusConflict, err
+		}
+		return http.StatusMethodNotAllowed, err
+	}
+	return http.StatusCreated, nil
+}
+
+func (h *Handler) handleCopyMove(w http.ResponseWriter, r *http.Request) (status int, err error) {
+	hdr := r.Header.Get("Destination")
+	if hdr == "" {
+		return http.StatusBadRequest, errInvalidDestination
+	}
+	u, err := url.Parse(hdr)
+	if err != nil {
+		return http.StatusBadRequest, errInvalidDestination
+	}
+	if u.Host != r.Host {
+		return http.StatusBadGateway, errInvalidDestination
+	}
+
+	src, status, err := h.stripPrefix(r.URL.Path)
+	if err != nil {
+		return status, err
+	}
+
+	dst, status, err := h.stripPrefix(u.Path)
+	if err != nil {
+		return status, err
+	}
+
+	if dst == "" {
+		return http.StatusBadGateway, errInvalidDestination
+	}
+	if dst == src {
+		return http.StatusForbidden, errDestinationEqualsSource
+	}
+
+	ctx := getContext(r)
+
+	if r.Method == "COPY" {
+		// Section 7.5.1 says that a COPY only needs to lock the destination,
+		// not both destination and source. Strictly speaking, this is racy,
+		// even though a COPY doesn't modify the source, if a concurrent
+		// operation modifies the source. However, the litmus test explicitly
+		// checks that COPYing a locked-by-another source is OK.
+		release, status, err := h.confirmLocks(r, "", dst)
+		if err != nil {
+			return status, err
+		}
+		defer release()
+
+		// Section 9.8.3 says that "The COPY method on a collection without a Depth
+		// header must act as if a Depth header with value "infinity" was included".
+		depth := infiniteDepth
+		if hdr := r.Header.Get("Depth"); hdr != "" {
+			depth = parseDepth(hdr)
+			if depth != 0 && depth != infiniteDepth {
+				// Section 9.8.3 says that "A client may submit a Depth header on a
+				// COPY on a collection with a value of "0" or "infinity"."
+				return http.StatusBadRequest, errInvalidDepth
+			}
+		}
+		return copyFiles(ctx, h.FileSystem, src, dst, r.Header.Get("Overwrite") != "F", depth, 0)
+	}
+
+	release, status, err := h.confirmLocks(r, src, dst)
+	if err != nil {
+		return status, err
+	}
+	defer release()
+
+	// Section 9.9.2 says that "The MOVE method on a collection must act as if
+	// a "Depth: infinity" header was used on it. A client must not submit a
+	// Depth header on a MOVE on a collection with any value but "infinity"."
+	if hdr := r.Header.Get("Depth"); hdr != "" {
+		if parseDepth(hdr) != infiniteDepth {
+			return http.StatusBadRequest, errInvalidDepth
+		}
+	}
+	return moveFiles(ctx, h.FileSystem, src, dst, r.Header.Get("Overwrite") == "T")
+}
+
+func (h *Handler) handleLock(w http.ResponseWriter, r *http.Request) (retStatus int, retErr error) {
+	duration, err := parseTimeout(r.Header.Get("Timeout"))
+	if err != nil {
+		return http.StatusBadRequest, err
+	}
+	li, status, err := readLockInfo(r.Body)
+	if err != nil {
+		return status, err
+	}
+
+	ctx := getContext(r)
+	token, ld, now, created := "", LockDetails{}, time.Now(), false
+	if li == (lockInfo{}) {
+		// An empty lockInfo means to refresh the lock.
+		ih, ok := parseIfHeader(r.Header.Get("If"))
+		if !ok {
+			return http.StatusBadRequest, errInvalidIfHeader
+		}
+		if len(ih.lists) == 1 && len(ih.lists[0].conditions) == 1 {
+			token = ih.lists[0].conditions[0].Token
+		}
+		if token == "" {
+			return http.StatusBadRequest, errInvalidLockToken
+		}
+		ld, err = h.LockSystem.Refresh(now, token, duration)
+		if err != nil {
+			if err == ErrNoSuchLock {
+				return http.StatusPreconditionFailed, err
+			}
+			return http.StatusInternalServerError, err
+		}
+
+	} else {
+		// Section 9.10.3 says that "If no Depth header is submitted on a LOCK request,
+		// then the request MUST act as if a "Depth:infinity" had been submitted."
+		depth := infiniteDepth
+		if hdr := r.Header.Get("Depth"); hdr != "" {
+			depth = parseDepth(hdr)
+			if depth != 0 && depth != infiniteDepth {
+				// Section 9.10.3 says that "Values other than 0 or infinity must not be
+				// used with the Depth header on a LOCK method".
+				return http.StatusBadRequest, errInvalidDepth
+			}
+		}
+		reqPath, status, err := h.stripPrefix(r.URL.Path)
+		if err != nil {
+			return status, err
+		}
+		ld = LockDetails{
+			Root:      reqPath,
+			Duration:  duration,
+			OwnerXML:  li.Owner.InnerXML,
+			ZeroDepth: depth == 0,
+		}
+		token, err = h.LockSystem.Create(now, ld)
+		if err != nil {
+			if err == ErrLocked {
+				return StatusLocked, err
+			}
+			return http.StatusInternalServerError, err
+		}
+		defer func() {
+			if retErr != nil {
+				h.LockSystem.Unlock(now, token)
+			}
+		}()
+
+		// Create the resource if it didn't previously exist.
+		if _, err := h.FileSystem.Stat(ctx, reqPath); err != nil {
+			f, err := h.FileSystem.OpenFile(ctx, reqPath, os.O_RDWR|os.O_CREATE|os.O_TRUNC, 0666)
+			if err != nil {
+				// TODO: detect missing intermediate dirs and return http.StatusConflict?
+				return http.StatusInternalServerError, err
+			}
+			f.Close()
+			created = true
+		}
+
+		// http://www.webdav.org/specs/rfc4918.html#HEADER_Lock-Token says that the
+		// Lock-Token value is a Coded-URL. We add angle brackets.
+		w.Header().Set("Lock-Token", "<"+token+">")
+	}
+
+	w.Header().Set("Content-Type", "application/xml; charset=utf-8")
+	if created {
+		// This is "w.WriteHeader(http.StatusCreated)" and not "return
+		// http.StatusCreated, nil" because we write our own (XML) response to w
+		// and Handler.ServeHTTP would otherwise write "Created".
+		w.WriteHeader(http.StatusCreated)
+	}
+	writeLockInfo(w, token, ld)
+	return 0, nil
+}
+
+func (h *Handler) handleUnlock(w http.ResponseWriter, r *http.Request) (status int, err error) {
+	// http://www.webdav.org/specs/rfc4918.html#HEADER_Lock-Token says that the
+	// Lock-Token value is a Coded-URL. We strip its angle brackets.
+	t := r.Header.Get("Lock-Token")
+	if len(t) < 2 || t[0] != '<' || t[len(t)-1] != '>' {
+		return http.StatusBadRequest, errInvalidLockToken
+	}
+	t = t[1 : len(t)-1]
+
+	switch err = h.LockSystem.Unlock(time.Now(), t); err {
+	case nil:
+		return http.StatusNoContent, err
+	case ErrForbidden:
+		return http.StatusForbidden, err
+	case ErrLocked:
+		return StatusLocked, err
+	case ErrNoSuchLock:
+		return http.StatusConflict, err
+	default:
+		return http.StatusInternalServerError, err
+	}
+}
+
+func (h *Handler) handlePropfind(w http.ResponseWriter, r *http.Request) (status int, err error) {
+	reqPath, status, err := h.stripPrefix(r.URL.Path)
+	if err != nil {
+		return status, err
+	}
+	ctx := getContext(r)
+	fi, err := h.FileSystem.Stat(ctx, reqPath)
+	if err != nil {
+		if os.IsNotExist(err) {
+			return http.StatusNotFound, err
+		}
+		return http.StatusMethodNotAllowed, err
+	}
+	depth := infiniteDepth
+	if hdr := r.Header.Get("Depth"); hdr != "" {
+		depth = parseDepth(hdr)
+		if depth == invalidDepth {
+			return http.StatusBadRequest, errInvalidDepth
+		}
+	}
+	pf, status, err := readPropfind(r.Body)
+	if err != nil {
+		return status, err
+	}
+
+	mw := multistatusWriter{w: w}
+
+	walkFn := func(reqPath string, info os.FileInfo, err error) error {
+		if err != nil {
+			return err
+		}
+		var pstats []Propstat
+		if pf.Propname != nil {
+			pnames, err := propnames(ctx, h.FileSystem, h.LockSystem, reqPath)
+			if err != nil {
+				return err
+			}
+			pstat := Propstat{Status: http.StatusOK}
+			for _, xmlname := range pnames {
+				pstat.Props = append(pstat.Props, Property{XMLName: xmlname})
+			}
+			pstats = append(pstats, pstat)
+		} else if pf.Allprop != nil {
+			pstats, err = allprop(ctx, h.FileSystem, h.LockSystem, reqPath, pf.Prop)
+		} else {
+			pstats, err = props(ctx, h.FileSystem, h.LockSystem, reqPath, pf.Prop)
+		}
+		if err != nil {
+			return err
+		}
+		return mw.write(makePropstatResponse(path.Join(h.Prefix, reqPath), pstats))
+	}
+
+	walkErr := walkFS(ctx, h.FileSystem, depth, reqPath, fi, walkFn)
+	closeErr := mw.close()
+	if walkErr != nil {
+		return http.StatusInternalServerError, walkErr
+	}
+	if closeErr != nil {
+		return http.StatusInternalServerError, closeErr
+	}
+	return 0, nil
+}
+
+func (h *Handler) handleProppatch(w http.ResponseWriter, r *http.Request) (status int, err error) {
+	reqPath, status, err := h.stripPrefix(r.URL.Path)
+	if err != nil {
+		return status, err
+	}
+	release, status, err := h.confirmLocks(r, reqPath, "")
+	if err != nil {
+		return status, err
+	}
+	defer release()
+
+	ctx := getContext(r)
+
+	if _, err := h.FileSystem.Stat(ctx, reqPath); err != nil {
+		if os.IsNotExist(err) {
+			return http.StatusNotFound, err
+		}
+		return http.StatusMethodNotAllowed, err
+	}
+	patches, status, err := readProppatch(r.Body)
+	if err != nil {
+		return status, err
+	}
+	pstats, err := patch(ctx, h.FileSystem, h.LockSystem, reqPath, patches)
+	if err != nil {
+		return http.StatusInternalServerError, err
+	}
+	mw := multistatusWriter{w: w}
+	writeErr := mw.write(makePropstatResponse(r.URL.Path, pstats))
+	closeErr := mw.close()
+	if writeErr != nil {
+		return http.StatusInternalServerError, writeErr
+	}
+	if closeErr != nil {
+		return http.StatusInternalServerError, closeErr
+	}
+	return 0, nil
+}
+
+func makePropstatResponse(href string, pstats []Propstat) *response {
+	resp := response{
+		Href:     []string{(&url.URL{Path: href}).EscapedPath()},
+		Propstat: make([]propstat, 0, len(pstats)),
+	}
+	for _, p := range pstats {
+		var xmlErr *xmlError
+		if p.XMLError != "" {
+			xmlErr = &xmlError{InnerXML: []byte(p.XMLError)}
+		}
+		resp.Propstat = append(resp.Propstat, propstat{
+			Status:              fmt.Sprintf("HTTP/1.1 %d %s", p.Status, StatusText(p.Status)),
+			Prop:                p.Props,
+			ResponseDescription: p.ResponseDescription,
+			Error:               xmlErr,
+		})
+	}
+	return &resp
+}
+
+const (
+	infiniteDepth = -1
+	invalidDepth  = -2
+)
+
+// parseDepth maps the strings "0", "1" and "infinity" to 0, 1 and
+// infiniteDepth. Parsing any other string returns invalidDepth.
+//
+// Different WebDAV methods have further constraints on valid depths:
+//	- PROPFIND has no further restrictions, as per section 9.1.
+//	- COPY accepts only "0" or "infinity", as per section 9.8.3.
+//	- MOVE accepts only "infinity", as per section 9.9.2.
+//	- LOCK accepts only "0" or "infinity", as per section 9.10.3.
+// These constraints are enforced by the handleXxx methods.
+func parseDepth(s string) int {
+	switch s {
+	case "0":
+		return 0
+	case "1":
+		return 1
+	case "infinity":
+		return infiniteDepth
+	}
+	return invalidDepth
+}
+
+// http://www.webdav.org/specs/rfc4918.html#status.code.extensions.to.http11
+const (
+	StatusMulti               = 207
+	StatusUnprocessableEntity = 422
+	StatusLocked              = 423
+	StatusFailedDependency    = 424
+	StatusInsufficientStorage = 507
+)
+
+func StatusText(code int) string {
+	switch code {
+	case StatusMulti:
+		return "Multi-Status"
+	case StatusUnprocessableEntity:
+		return "Unprocessable Entity"
+	case StatusLocked:
+		return "Locked"
+	case StatusFailedDependency:
+		return "Failed Dependency"
+	case StatusInsufficientStorage:
+		return "Insufficient Storage"
+	}
+	return http.StatusText(code)
+}
+
+var (
+	errDestinationEqualsSource = errors.New("webdav: destination equals source")
+	errDirectoryNotEmpty       = errors.New("webdav: directory not empty")
+	errInvalidDepth            = errors.New("webdav: invalid depth")
+	errInvalidDestination      = errors.New("webdav: invalid destination")
+	errInvalidIfHeader         = errors.New("webdav: invalid If header")
+	errInvalidLockInfo         = errors.New("webdav: invalid lock info")
+	errInvalidLockToken        = errors.New("webdav: invalid lock token")
+	errInvalidPropfind         = errors.New("webdav: invalid propfind")
+	errInvalidProppatch        = errors.New("webdav: invalid proppatch")
+	errInvalidResponse         = errors.New("webdav: invalid response")
+	errInvalidTimeout          = errors.New("webdav: invalid timeout")
+	errNoFileSystem            = errors.New("webdav: no file system")
+	errNoLockSystem            = errors.New("webdav: no lock system")
+	errNotADirectory           = errors.New("webdav: not a directory")
+	errPrefixMismatch          = errors.New("webdav: prefix mismatch")
+	errRecursionTooDeep        = errors.New("webdav: recursion too deep")
+	errUnsupportedLockInfo     = errors.New("webdav: unsupported lock info")
+	errUnsupportedMethod       = errors.New("webdav: unsupported method")
+)

vendor/golang.org/x/net/webdav/xml.go

@@ -0,0 +1,519 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package webdav
+
+// The XML encoding is covered by Section 14.
+// http://www.webdav.org/specs/rfc4918.html#xml.element.definitions
+
+import (
+	"bytes"
+	"encoding/xml"
+	"fmt"
+	"io"
+	"net/http"
+	"time"
+
+	// As of https://go-review.googlesource.com/#/c/12772/ which was submitted
+	// in July 2015, this package uses an internal fork of the standard
+	// library's encoding/xml package, due to changes in the way namespaces
+	// were encoded. Such changes were introduced in the Go 1.5 cycle, but were
+	// rolled back in response to https://github.com/golang/go/issues/11841
+	//
+	// However, this package's exported API, specifically the Property and
+	// DeadPropsHolder types, need to refer to the standard library's version
+	// of the xml.Name type, as code that imports this package cannot refer to
+	// the internal version.
+	//
+	// This file therefore imports both the internal and external versions, as
+	// ixml and xml, and converts between them.
+	//
+	// In the long term, this package should use the standard library's version
+	// only, and the internal fork deleted, once
+	// https://github.com/golang/go/issues/13400 is resolved.
+	ixml "golang.org/x/net/webdav/internal/xml"
+)
+
+// http://www.webdav.org/specs/rfc4918.html#ELEMENT_lockinfo
+type lockInfo struct {
+	XMLName   ixml.Name `xml:"lockinfo"`
+	Exclusive *struct{} `xml:"lockscope>exclusive"`
+	Shared    *struct{} `xml:"lockscope>shared"`
+	Write     *struct{} `xml:"locktype>write"`
+	Owner     owner     `xml:"owner"`
+}
+
+// http://www.webdav.org/specs/rfc4918.html#ELEMENT_owner
+type owner struct {
+	InnerXML string `xml:",innerxml"`
+}
+
+func readLockInfo(r io.Reader) (li lockInfo, status int, err error) {
+	c := &countingReader{r: r}
+	if err = ixml.NewDecoder(c).Decode(&li); err != nil {
+		if err == io.EOF {
+			if c.n == 0 {
+				// An empty body means to refresh the lock.
+				// http://www.webdav.org/specs/rfc4918.html#refreshing-locks
+				return lockInfo{}, 0, nil
+			}
+			err = errInvalidLockInfo
+		}
+		return lockInfo{}, http.StatusBadRequest, err
+	}
+	// We only support exclusive (non-shared) write locks. In practice, these are
+	// the only types of locks that seem to matter.
+	if li.Exclusive == nil || li.Shared != nil || li.Write == nil {
+		return lockInfo{}, http.StatusNotImplemented, errUnsupportedLockInfo
+	}
+	return li, 0, nil
+}
+
+type countingReader struct {
+	n int
+	r io.Reader
+}
+
+func (c *countingReader) Read(p []byte) (int, error) {
+	n, err := c.r.Read(p)
+	c.n += n
+	return n, err
+}
+
+func writeLockInfo(w io.Writer, token string, ld LockDetails) (int, error) {
+	depth := "infinity"
+	if ld.ZeroDepth {
+		depth = "0"
+	}
+	timeout := ld.Duration / time.Second
+	return fmt.Fprintf(w, "<?xml version=\"1.0\" encoding=\"utf-8\"?>\n"+
+		"<D:prop xmlns:D=\"DAV:\"><D:lockdiscovery><D:activelock>\n"+
+		"	<D:locktype><D:write/></D:locktype>\n"+
+		"	<D:lockscope><D:exclusive/></D:lockscope>\n"+
+		"	<D:depth>%s</D:depth>\n"+
+		"	<D:owner>%s</D:owner>\n"+
+		"	<D:timeout>Second-%d</D:timeout>\n"+
+		"	<D:locktoken><D:href>%s</D:href></D:locktoken>\n"+
+		"	<D:lockroot><D:href>%s</D:href></D:lockroot>\n"+
+		"</D:activelock></D:lockdiscovery></D:prop>",
+		depth, ld.OwnerXML, timeout, escape(token), escape(ld.Root),
+	)
+}
+
+func escape(s string) string {
+	for i := 0; i < len(s); i++ {
+		switch s[i] {
+		case '"', '&', '\'', '<', '>':
+			b := bytes.NewBuffer(nil)
+			ixml.EscapeText(b, []byte(s))
+			return b.String()
+		}
+	}
+	return s
+}
+
+// Next returns the next token, if any, in the XML stream of d.
+// RFC 4918 requires to ignore comments, processing instructions
+// and directives.
+// http://www.webdav.org/specs/rfc4918.html#property_values
+// http://www.webdav.org/specs/rfc4918.html#xml-extensibility
+func next(d *ixml.Decoder) (ixml.Token, error) {
+	for {
+		t, err := d.Token()
+		if err != nil {
+			return t, err
+		}
+		switch t.(type) {
+		case ixml.Comment, ixml.Directive, ixml.ProcInst:
+			continue
+		default:
+			return t, nil
+		}
+	}
+}
+
+// http://www.webdav.org/specs/rfc4918.html#ELEMENT_prop (for propfind)
+type propfindProps []xml.Name
+
+// UnmarshalXML appends the property names enclosed within start to pn.
+//
+// It returns an error if start does not contain any properties or if
+// properties contain values. Character data between properties is ignored.
+func (pn *propfindProps) UnmarshalXML(d *ixml.Decoder, start ixml.StartElement) error {
+	for {
+		t, err := next(d)
+		if err != nil {
+			return err
+		}
+		switch t.(type) {
+		case ixml.EndElement:
+			if len(*pn) == 0 {
+				return fmt.Errorf("%s must not be empty", start.Name.Local)
+			}
+			return nil
+		case ixml.StartElement:
+			name := t.(ixml.StartElement).Name
+			t, err = next(d)
+			if err != nil {
+				return err
+			}
+			if _, ok := t.(ixml.EndElement); !ok {
+				return fmt.Errorf("unexpected token %T", t)
+			}
+			*pn = append(*pn, xml.Name(name))
+		}
+	}
+}
+
+// http://www.webdav.org/specs/rfc4918.html#ELEMENT_propfind
+type propfind struct {
+	XMLName  ixml.Name     `xml:"DAV: propfind"`
+	Allprop  *struct{}     `xml:"DAV: allprop"`
+	Propname *struct{}     `xml:"DAV: propname"`
+	Prop     propfindProps `xml:"DAV: prop"`
+	Include  propfindProps `xml:"DAV: include"`
+}
+
+func readPropfind(r io.Reader) (pf propfind, status int, err error) {
+	c := countingReader{r: r}
+	if err = ixml.NewDecoder(&c).Decode(&pf); err != nil {
+		if err == io.EOF {
+			if c.n == 0 {
+				// An empty body means to propfind allprop.
+				// http://www.webdav.org/specs/rfc4918.html#METHOD_PROPFIND
+				return propfind{Allprop: new(struct{})}, 0, nil
+			}
+			err = errInvalidPropfind
+		}
+		return propfind{}, http.StatusBadRequest, err
+	}
+
+	if pf.Allprop == nil && pf.Include != nil {
+		return propfind{}, http.StatusBadRequest, errInvalidPropfind
+	}
+	if pf.Allprop != nil && (pf.Prop != nil || pf.Propname != nil) {
+		return propfind{}, http.StatusBadRequest, errInvalidPropfind
+	}
+	if pf.Prop != nil && pf.Propname != nil {
+		return propfind{}, http.StatusBadRequest, errInvalidPropfind
+	}
+	if pf.Propname == nil && pf.Allprop == nil && pf.Prop == nil {
+		return propfind{}, http.StatusBadRequest, errInvalidPropfind
+	}
+	return pf, 0, nil
+}
+
+// Property represents a single DAV resource property as defined in RFC 4918.
+// See http://www.webdav.org/specs/rfc4918.html#data.model.for.resource.properties
+type Property struct {
+	// XMLName is the fully qualified name that identifies this property.
+	XMLName xml.Name
+
+	// Lang is an optional xml:lang attribute.
+	Lang string `xml:"xml:lang,attr,omitempty"`
+
+	// InnerXML contains the XML representation of the property value.
+	// See http://www.webdav.org/specs/rfc4918.html#property_values
+	//
+	// Property values of complex type or mixed-content must have fully
+	// expanded XML namespaces or be self-contained with according
+	// XML namespace declarations. They must not rely on any XML
+	// namespace declarations within the scope of the XML document,
+	// even including the DAV: namespace.
+	InnerXML []byte `xml:",innerxml"`
+}
+
+// ixmlProperty is the same as the Property type except it holds an ixml.Name
+// instead of an xml.Name.
+type ixmlProperty struct {
+	XMLName  ixml.Name
+	Lang     string `xml:"xml:lang,attr,omitempty"`
+	InnerXML []byte `xml:",innerxml"`
+}
+
+// http://www.webdav.org/specs/rfc4918.html#ELEMENT_error
+// See multistatusWriter for the "D:" namespace prefix.
+type xmlError struct {
+	XMLName  ixml.Name `xml:"D:error"`
+	InnerXML []byte    `xml:",innerxml"`
+}
+
+// http://www.webdav.org/specs/rfc4918.html#ELEMENT_propstat
+// See multistatusWriter for the "D:" namespace prefix.
+type propstat struct {
+	Prop                []Property `xml:"D:prop>_ignored_"`
+	Status              string     `xml:"D:status"`
+	Error               *xmlError  `xml:"D:error"`
+	ResponseDescription string     `xml:"D:responsedescription,omitempty"`
+}
+
+// ixmlPropstat is the same as the propstat type except it holds an ixml.Name
+// instead of an xml.Name.
+type ixmlPropstat struct {
+	Prop                []ixmlProperty `xml:"D:prop>_ignored_"`
+	Status              string         `xml:"D:status"`
+	Error               *xmlError      `xml:"D:error"`
+	ResponseDescription string         `xml:"D:responsedescription,omitempty"`
+}
+
+// MarshalXML prepends the "D:" namespace prefix on properties in the DAV: namespace
+// before encoding. See multistatusWriter.
+func (ps propstat) MarshalXML(e *ixml.Encoder, start ixml.StartElement) error {
+	// Convert from a propstat to an ixmlPropstat.
+	ixmlPs := ixmlPropstat{
+		Prop:                make([]ixmlProperty, len(ps.Prop)),
+		Status:              ps.Status,
+		Error:               ps.Error,
+		ResponseDescription: ps.ResponseDescription,
+	}
+	for k, prop := range ps.Prop {
+		ixmlPs.Prop[k] = ixmlProperty{
+			XMLName:  ixml.Name(prop.XMLName),
+			Lang:     prop.Lang,
+			InnerXML: prop.InnerXML,
+		}
+	}
+
+	for k, prop := range ixmlPs.Prop {
+		if prop.XMLName.Space == "DAV:" {
+			prop.XMLName = ixml.Name{Space: "", Local: "D:" + prop.XMLName.Local}
+			ixmlPs.Prop[k] = prop
+		}
+	}
+	// Distinct type to avoid infinite recursion of MarshalXML.
+	type newpropstat ixmlPropstat
+	return e.EncodeElement(newpropstat(ixmlPs), start)
+}
+
+// http://www.webdav.org/specs/rfc4918.html#ELEMENT_response
+// See multistatusWriter for the "D:" namespace prefix.
+type response struct {
+	XMLName             ixml.Name  `xml:"D:response"`
+	Href                []string   `xml:"D:href"`
+	Propstat            []propstat `xml:"D:propstat"`
+	Status              string     `xml:"D:status,omitempty"`
+	Error               *xmlError  `xml:"D:error"`
+	ResponseDescription string     `xml:"D:responsedescription,omitempty"`
+}
+
+// MultistatusWriter marshals one or more Responses into a XML
+// multistatus response.
+// See http://www.webdav.org/specs/rfc4918.html#ELEMENT_multistatus
+// TODO(rsto, mpl): As a workaround, the "D:" namespace prefix, defined as
+// "DAV:" on this element, is prepended on the nested response, as well as on all
+// its nested elements. All property names in the DAV: namespace are prefixed as
+// well. This is because some versions of Mini-Redirector (on windows 7) ignore
+// elements with a default namespace (no prefixed namespace). A less intrusive fix
+// should be possible after golang.org/cl/11074. See https://golang.org/issue/11177
+type multistatusWriter struct {
+	// ResponseDescription contains the optional responsedescription
+	// of the multistatus XML element. Only the latest content before
+	// close will be emitted. Empty response descriptions are not
+	// written.
+	responseDescription string
+
+	w   http.ResponseWriter
+	enc *ixml.Encoder
+}
+
+// Write validates and emits a DAV response as part of a multistatus response
+// element.
+//
+// It sets the HTTP status code of its underlying http.ResponseWriter to 207
+// (Multi-Status) and populates the Content-Type header. If r is the
+// first, valid response to be written, Write prepends the XML representation
+// of r with a multistatus tag. Callers must call close after the last response
+// has been written.
+func (w *multistatusWriter) write(r *response) error {
+	switch len(r.Href) {
+	case 0:
+		return errInvalidResponse
+	case 1:
+		if len(r.Propstat) > 0 != (r.Status == "") {
+			return errInvalidResponse
+		}
+	default:
+		if len(r.Propstat) > 0 || r.Status == "" {
+			return errInvalidResponse
+		}
+	}
+	err := w.writeHeader()
+	if err != nil {
+		return err
+	}
+	return w.enc.Encode(r)
+}
+
+// writeHeader writes a XML multistatus start element on w's underlying
+// http.ResponseWriter and returns the result of the write operation.
+// After the first write attempt, writeHeader becomes a no-op.
+func (w *multistatusWriter) writeHeader() error {
+	if w.enc != nil {
+		return nil
+	}
+	w.w.Header().Add("Content-Type", "text/xml; charset=utf-8")
+	w.w.WriteHeader(StatusMulti)
+	_, err := fmt.Fprintf(w.w, `<?xml version="1.0" encoding="UTF-8"?>`)
+	if err != nil {
+		return err
+	}
+	w.enc = ixml.NewEncoder(w.w)
+	return w.enc.EncodeToken(ixml.StartElement{
+		Name: ixml.Name{
+			Space: "DAV:",
+			Local: "multistatus",
+		},
+		Attr: []ixml.Attr{{
+			Name:  ixml.Name{Space: "xmlns", Local: "D"},
+			Value: "DAV:",
+		}},
+	})
+}
+
+// Close completes the marshalling of the multistatus response. It returns
+// an error if the multistatus response could not be completed. If both the
+// return value and field enc of w are nil, then no multistatus response has
+// been written.
+func (w *multistatusWriter) close() error {
+	if w.enc == nil {
+		return nil
+	}
+	var end []ixml.Token
+	if w.responseDescription != "" {
+		name := ixml.Name{Space: "DAV:", Local: "responsedescription"}
+		end = append(end,
+			ixml.StartElement{Name: name},
+			ixml.CharData(w.responseDescription),
+			ixml.EndElement{Name: name},
+		)
+	}
+	end = append(end, ixml.EndElement{
+		Name: ixml.Name{Space: "DAV:", Local: "multistatus"},
+	})
+	for _, t := range end {
+		err := w.enc.EncodeToken(t)
+		if err != nil {
+			return err
+		}
+	}
+	return w.enc.Flush()
+}
+
+var xmlLangName = ixml.Name{Space: "http://www.w3.org/XML/1998/namespace", Local: "lang"}
+
+func xmlLang(s ixml.StartElement, d string) string {
+	for _, attr := range s.Attr {
+		if attr.Name == xmlLangName {
+			return attr.Value
+		}
+	}
+	return d
+}
+
+type xmlValue []byte
+
+func (v *xmlValue) UnmarshalXML(d *ixml.Decoder, start ixml.StartElement) error {
+	// The XML value of a property can be arbitrary, mixed-content XML.
+	// To make sure that the unmarshalled value contains all required
+	// namespaces, we encode all the property value XML tokens into a
+	// buffer. This forces the encoder to redeclare any used namespaces.
+	var b bytes.Buffer
+	e := ixml.NewEncoder(&b)
+	for {
+		t, err := next(d)
+		if err != nil {
+			return err
+		}
+		if e, ok := t.(ixml.EndElement); ok && e.Name == start.Name {
+			break
+		}
+		if err = e.EncodeToken(t); err != nil {
+			return err
+		}
+	}
+	err := e.Flush()
+	if err != nil {
+		return err
+	}
+	*v = b.Bytes()
+	return nil
+}
+
+// http://www.webdav.org/specs/rfc4918.html#ELEMENT_prop (for proppatch)
+type proppatchProps []Property
+
+// UnmarshalXML appends the property names and values enclosed within start
+// to ps.
+//
+// An xml:lang attribute that is defined either on the DAV:prop or property
+// name XML element is propagated to the property's Lang field.
+//
+// UnmarshalXML returns an error if start does not contain any properties or if
+// property values contain syntactically incorrect XML.
+func (ps *proppatchProps) UnmarshalXML(d *ixml.Decoder, start ixml.StartElement) error {
+	lang := xmlLang(start, "")
+	for {
+		t, err := next(d)
+		if err != nil {
+			return err
+		}
+		switch elem := t.(type) {
+		case ixml.EndElement:
+			if len(*ps) == 0 {
+				return fmt.Errorf("%s must not be empty", start.Name.Local)
+			}
+			return nil
+		case ixml.StartElement:
+			p := Property{
+				XMLName: xml.Name(t.(ixml.StartElement).Name),
+				Lang:    xmlLang(t.(ixml.StartElement), lang),
+			}
+			err = d.DecodeElement(((*xmlValue)(&p.InnerXML)), &elem)
+			if err != nil {
+				return err
+			}
+			*ps = append(*ps, p)
+		}
+	}
+}
+
+// http://www.webdav.org/specs/rfc4918.html#ELEMENT_set
+// http://www.webdav.org/specs/rfc4918.html#ELEMENT_remove
+type setRemove struct {
+	XMLName ixml.Name
+	Lang    string         `xml:"xml:lang,attr,omitempty"`
+	Prop    proppatchProps `xml:"DAV: prop"`
+}
+
+// http://www.webdav.org/specs/rfc4918.html#ELEMENT_propertyupdate
+type propertyupdate struct {
+	XMLName   ixml.Name   `xml:"DAV: propertyupdate"`
+	Lang      string      `xml:"xml:lang,attr,omitempty"`
+	SetRemove []setRemove `xml:",any"`
+}
+
+func readProppatch(r io.Reader) (patches []Proppatch, status int, err error) {
+	var pu propertyupdate
+	if err = ixml.NewDecoder(r).Decode(&pu); err != nil {
+		return nil, http.StatusBadRequest, err
+	}
+	for _, op := range pu.SetRemove {
+		remove := false
+		switch op.XMLName {
+		case ixml.Name{Space: "DAV:", Local: "set"}:
+			// No-op.
+		case ixml.Name{Space: "DAV:", Local: "remove"}:
+			for _, p := range op.Prop {
+				if len(p.InnerXML) > 0 {
+					return nil, http.StatusBadRequest, errInvalidProppatch
+				}
+			}
+			remove = true
+		default:
+			return nil, http.StatusBadRequest, errInvalidProppatch
+		}
+		patches = append(patches, Proppatch{Remove: remove, Props: op.Prop})
+	}
+	return patches, 0, nil
+}