From 72150bef10eeaf8bc33f0b09c9e38e33f3830c3e Mon Sep 17 00:00:00 2001 From: Stephen J Day Date: Fri, 16 Dec 2016 16:30:11 -0800 Subject: [PATCH] vendor: add opencontainers/go-digest to vendor.conf Signed-off-by: Stephen J Day --- vendor.conf | 1 + .../opencontainers/go-digest/algorithm.go | 144 ++++++++++++++++++ .../opencontainers/go-digest/digest.go | 140 +++++++++++++++++ .../opencontainers/go-digest/digester.go | 25 +++ .../opencontainers/go-digest/doc.go | 42 +++++ .../opencontainers/go-digest/verifiers.go | 31 ++++ 6 files changed, 383 insertions(+) create mode 100644 vendor/github.com/opencontainers/go-digest/algorithm.go create mode 100644 vendor/github.com/opencontainers/go-digest/digest.go create mode 100644 vendor/github.com/opencontainers/go-digest/digester.go create mode 100644 vendor/github.com/opencontainers/go-digest/doc.go create mode 100644 vendor/github.com/opencontainers/go-digest/verifiers.go diff --git a/vendor.conf b/vendor.conf index 7ebddd06c..8ef953a15 100644 --- a/vendor.conf +++ b/vendor.conf @@ -37,3 +37,4 @@ gopkg.in/check.v1 64131543e7896d5bcc6bd5a76287eb75ea96c673 gopkg.in/square/go-jose.v1 40d457b439244b546f023d056628e5184136899b gopkg.in/yaml.v2 bef53efd0c76e49e6de55ead051f886bea7e9420 rsc.io/letsencrypt e770c10b0f1a64775ae91d240407ce00d1a5bdeb https://github.com/dmcgowan/letsencrypt.git +github.com/opencontainers/go-digest a6d0ee40d4207ea02364bd3b9e8e77b9159ba1eb diff --git a/vendor/github.com/opencontainers/go-digest/algorithm.go b/vendor/github.com/opencontainers/go-digest/algorithm.go new file mode 100644 index 000000000..a3c44801d --- /dev/null +++ b/vendor/github.com/opencontainers/go-digest/algorithm.go @@ -0,0 +1,144 @@ +package digest + +import ( + "crypto" + "fmt" + "hash" + "io" +) + +// Algorithm identifies and implementation of a digester by an identifier. +// Note the that this defines both the hash algorithm used and the string +// encoding. +type Algorithm string + +// supported digest types +const ( + SHA256 Algorithm = "sha256" // sha256 with hex encoding + SHA384 Algorithm = "sha384" // sha384 with hex encoding + SHA512 Algorithm = "sha512" // sha512 with hex encoding + + // Canonical is the primary digest algorithm used with the distribution + // project. Other digests may be used but this one is the primary storage + // digest. + Canonical = SHA256 +) + +var ( + // TODO(stevvooe): Follow the pattern of the standard crypto package for + // registration of digests. Effectively, we are a registerable set and + // common symbol access. + + // algorithms maps values to hash.Hash implementations. Other algorithms + // may be available but they cannot be calculated by the digest package. + algorithms = map[Algorithm]crypto.Hash{ + SHA256: crypto.SHA256, + SHA384: crypto.SHA384, + SHA512: crypto.SHA512, + } +) + +// Available returns true if the digest type is available for use. If this +// returns false, Digester and Hash will return nil. +func (a Algorithm) Available() bool { + h, ok := algorithms[a] + if !ok { + return false + } + + // check availability of the hash, as well + return h.Available() +} + +func (a Algorithm) String() string { + return string(a) +} + +// Size returns number of bytes returned by the hash. +func (a Algorithm) Size() int { + h, ok := algorithms[a] + if !ok { + return 0 + } + return h.Size() +} + +// Set implemented to allow use of Algorithm as a command line flag. +func (a *Algorithm) Set(value string) error { + if value == "" { + *a = Canonical + } else { + // just do a type conversion, support is queried with Available. + *a = Algorithm(value) + } + + if !a.Available() { + return ErrDigestUnsupported + } + + return nil +} + +// Digester returns a new digester for the specified algorithm. If the algorithm +// does not have a digester implementation, nil will be returned. This can be +// checked by calling Available before calling Digester. +func (a Algorithm) Digester() Digester { + return &digester{ + alg: a, + hash: a.Hash(), + } +} + +// Hash returns a new hash as used by the algorithm. If not available, the +// method will panic. Check Algorithm.Available() before calling. +func (a Algorithm) Hash() hash.Hash { + if !a.Available() { + // Empty algorithm string is invalid + if a == "" { + panic(fmt.Sprintf("empty digest algorithm, validate before calling Algorithm.Hash()")) + } + + // NOTE(stevvooe): A missing hash is usually a programming error that + // must be resolved at compile time. We don't import in the digest + // package to allow users to choose their hash implementation (such as + // when using stevvooe/resumable or a hardware accelerated package). + // + // Applications that may want to resolve the hash at runtime should + // call Algorithm.Available before call Algorithm.Hash(). + panic(fmt.Sprintf("%v not available (make sure it is imported)", a)) + } + + return algorithms[a].New() +} + +// FromReader returns the digest of the reader using the algorithm. +func (a Algorithm) FromReader(rd io.Reader) (Digest, error) { + digester := a.Digester() + + if _, err := io.Copy(digester.Hash(), rd); err != nil { + return "", err + } + + return digester.Digest(), nil +} + +// FromBytes digests the input and returns a Digest. +func (a Algorithm) FromBytes(p []byte) Digest { + digester := a.Digester() + + if _, err := digester.Hash().Write(p); err != nil { + // Writes to a Hash should never fail. None of the existing + // hash implementations in the stdlib or hashes vendored + // here can return errors from Write. Having a panic in this + // condition instead of having FromBytes return an error value + // avoids unnecessary error handling paths in all callers. + panic("write to hash function returned error: " + err.Error()) + } + + return digester.Digest() +} + +// FromString digests the string input and returns a Digest. +func (a Algorithm) FromString(s string) Digest { + return a.FromBytes([]byte(s)) +} diff --git a/vendor/github.com/opencontainers/go-digest/digest.go b/vendor/github.com/opencontainers/go-digest/digest.go new file mode 100644 index 000000000..7c66c30c0 --- /dev/null +++ b/vendor/github.com/opencontainers/go-digest/digest.go @@ -0,0 +1,140 @@ +package digest + +import ( + "fmt" + "hash" + "io" + "regexp" + "strings" +) + +// Digest allows simple protection of hex formatted digest strings, prefixed +// by their algorithm. Strings of type Digest have some guarantee of being in +// the correct format and it provides quick access to the components of a +// digest string. +// +// The following is an example of the contents of Digest types: +// +// sha256:7173b809ca12ec5dee4506cd86be934c4596dd234ee82c0662eac04a8c2c71dc +// +// This allows to abstract the digest behind this type and work only in those +// terms. +type Digest string + +// NewDigest returns a Digest from alg and a hash.Hash object. +func NewDigest(alg Algorithm, h hash.Hash) Digest { + return NewDigestFromBytes(alg, h.Sum(nil)) +} + +// NewDigestFromBytes returns a new digest from the byte contents of p. +// Typically, this can come from hash.Hash.Sum(...) or xxx.SumXXX(...) +// functions. This is also useful for rebuilding digests from binary +// serializations. +func NewDigestFromBytes(alg Algorithm, p []byte) Digest { + return Digest(fmt.Sprintf("%s:%x", alg, p)) +} + +// NewDigestFromHex returns a Digest from alg and a the hex encoded digest. +func NewDigestFromHex(alg, hex string) Digest { + return Digest(fmt.Sprintf("%s:%s", alg, hex)) +} + +// DigestRegexp matches valid digest types. +var DigestRegexp = regexp.MustCompile(`[a-zA-Z0-9-_+.]+:[a-fA-F0-9]+`) + +// DigestRegexpAnchored matches valid digest types, anchored to the start and end of the match. +var DigestRegexpAnchored = regexp.MustCompile(`^` + DigestRegexp.String() + `$`) + +var ( + // ErrDigestInvalidFormat returned when digest format invalid. + ErrDigestInvalidFormat = fmt.Errorf("invalid checksum digest format") + + // ErrDigestInvalidLength returned when digest has invalid length. + ErrDigestInvalidLength = fmt.Errorf("invalid checksum digest length") + + // ErrDigestUnsupported returned when the digest algorithm is unsupported. + ErrDigestUnsupported = fmt.Errorf("unsupported digest algorithm") +) + +// Parse parses s and returns the validated digest object. An error will +// be returned if the format is invalid. +func Parse(s string) (Digest, error) { + d := Digest(s) + return d, d.Validate() +} + +// FromReader consumes the content of rd until io.EOF, returning canonical digest. +func FromReader(rd io.Reader) (Digest, error) { + return Canonical.FromReader(rd) +} + +// FromBytes digests the input and returns a Digest. +func FromBytes(p []byte) Digest { + return Canonical.FromBytes(p) +} + +// FromString digests the input and returns a Digest. +func FromString(s string) Digest { + return Canonical.FromString(s) +} + +// Validate checks that the contents of d is a valid digest, returning an +// error if not. +func (d Digest) Validate() error { + s := string(d) + + i := strings.Index(s, ":") + + // validate i then run through regexp + if i < 0 || i+1 == len(s) || !DigestRegexpAnchored.MatchString(s) { + return ErrDigestInvalidFormat + } + + algorithm := Algorithm(s[:i]) + if !algorithm.Available() { + return ErrDigestUnsupported + } + + // Digests much always be hex-encoded, ensuring that their hex portion will + // always be size*2 + if algorithm.Size()*2 != len(s[i+1:]) { + return ErrDigestInvalidLength + } + + return nil +} + +// Algorithm returns the algorithm portion of the digest. This will panic if +// the underlying digest is not in a valid format. +func (d Digest) Algorithm() Algorithm { + return Algorithm(d[:d.sepIndex()]) +} + +// Verifier returns a writer object that can be used to verify a stream of +// content against the digest. If the digest is invalid, the method will panic. +func (d Digest) Verifier() Verifier { + return hashVerifier{ + hash: d.Algorithm().Hash(), + digest: d, + } +} + +// Hex returns the hex digest portion of the digest. This will panic if the +// underlying digest is not in a valid format. +func (d Digest) Hex() string { + return string(d[d.sepIndex()+1:]) +} + +func (d Digest) String() string { + return string(d) +} + +func (d Digest) sepIndex() int { + i := strings.Index(string(d), ":") + + if i < 0 { + panic(fmt.Sprintf("no ':' separator in digest %q", d)) + } + + return i +} diff --git a/vendor/github.com/opencontainers/go-digest/digester.go b/vendor/github.com/opencontainers/go-digest/digester.go new file mode 100644 index 000000000..918a3f919 --- /dev/null +++ b/vendor/github.com/opencontainers/go-digest/digester.go @@ -0,0 +1,25 @@ +package digest + +import "hash" + +// Digester calculates the digest of written data. Writes should go directly +// to the return value of Hash, while calling Digest will return the current +// value of the digest. +type Digester interface { + Hash() hash.Hash // provides direct access to underlying hash instance. + Digest() Digest +} + +// digester provides a simple digester definition that embeds a hasher. +type digester struct { + alg Algorithm + hash hash.Hash +} + +func (d *digester) Hash() hash.Hash { + return d.hash +} + +func (d *digester) Digest() Digest { + return NewDigest(d.alg, d.hash) +} diff --git a/vendor/github.com/opencontainers/go-digest/doc.go b/vendor/github.com/opencontainers/go-digest/doc.go new file mode 100644 index 000000000..f64b0db32 --- /dev/null +++ b/vendor/github.com/opencontainers/go-digest/doc.go @@ -0,0 +1,42 @@ +// Package digest provides a generalized type to opaquely represent message +// digests and their operations within the registry. The Digest type is +// designed to serve as a flexible identifier in a content-addressable system. +// More importantly, it provides tools and wrappers to work with +// hash.Hash-based digests with little effort. +// +// Basics +// +// The format of a digest is simply a string with two parts, dubbed the +// "algorithm" and the "digest", separated by a colon: +// +// : +// +// An example of a sha256 digest representation follows: +// +// sha256:7173b809ca12ec5dee4506cd86be934c4596dd234ee82c0662eac04a8c2c71dc +// +// In this case, the string "sha256" is the algorithm and the hex bytes are +// the "digest". +// +// Because the Digest type is simply a string, once a valid Digest is +// obtained, comparisons are cheap, quick and simple to express with the +// standard equality operator. +// +// Verification +// +// The main benefit of using the Digest type is simple verification against a +// given digest. The Verifier interface, modeled after the stdlib hash.Hash +// interface, provides a common write sink for digest verification. After +// writing is complete, calling the Verifier.Verified method will indicate +// whether or not the stream of bytes matches the target digest. +// +// Missing Features +// +// In addition to the above, we intend to add the following features to this +// package: +// +// 1. A Digester type that supports write sink digest calculation. +// +// 2. Suspend and resume of ongoing digest calculations to support efficient digest verification in the registry. +// +package digest diff --git a/vendor/github.com/opencontainers/go-digest/verifiers.go b/vendor/github.com/opencontainers/go-digest/verifiers.go new file mode 100644 index 000000000..f1db6cda8 --- /dev/null +++ b/vendor/github.com/opencontainers/go-digest/verifiers.go @@ -0,0 +1,31 @@ +package digest + +import ( + "hash" + "io" +) + +// Verifier presents a general verification interface to be used with message +// digests and other byte stream verifications. Users instantiate a Verifier +// from one of the various methods, write the data under test to it then check +// the result with the Verified method. +type Verifier interface { + io.Writer + + // Verified will return true if the content written to Verifier matches + // the digest. + Verified() bool +} + +type hashVerifier struct { + digest Digest + hash hash.Hash +} + +func (hv hashVerifier) Write(p []byte) (n int, err error) { + return hv.hash.Write(p) +} + +func (hv hashVerifier) Verified() bool { + return hv.digest == NewDigest(hv.digest.Algorithm(), hv.hash) +}