Update runc to ce450bcc6c135cae93ee2a99d41a308c179ff6dc

Signed-off-by: Michael Crosby <crosbymichael@gmail.com>
This commit is contained in:
Michael Crosby 2017-01-24 14:57:11 -08:00
parent e09b0b0c35
commit 271cac8634
13 changed files with 1254 additions and 5 deletions

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/*
* Copyright 2016 SUSE LLC
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <unistd.h>
#include "cmsg.h"
#define error(fmt, ...) \
({ \
fprintf(stderr, "nsenter: " fmt ": %m\n", ##__VA_ARGS__); \
errno = ECOMM; \
goto err; /* return value */ \
})
/*
* Sends a file descriptor along the sockfd provided. Returns the return
* value of sendmsg(2). Any synchronisation and preparation of state
* should be done external to this (we expect the other side to be in
* recvfd() in the code).
*/
ssize_t sendfd(int sockfd, struct file_t file)
{
struct msghdr msg = {0};
struct iovec iov[1] = {0};
struct cmsghdr *cmsg;
int *fdptr;
int ret;
union {
char buf[CMSG_SPACE(sizeof(file.fd))];
struct cmsghdr align;
} u;
/*
* We need to send some other data along with the ancillary data,
* otherwise the other side won't recieve any data. This is very
* well-hidden in the documentation (and only applies to
* SOCK_STREAM). See the bottom part of unix(7).
*/
iov[0].iov_base = file.name;
iov[0].iov_len = strlen(file.name) + 1;
msg.msg_name = NULL;
msg.msg_namelen = 0;
msg.msg_iov = iov;
msg.msg_iovlen = 1;
msg.msg_control = u.buf;
msg.msg_controllen = sizeof(u.buf);
cmsg = CMSG_FIRSTHDR(&msg);
cmsg->cmsg_level = SOL_SOCKET;
cmsg->cmsg_type = SCM_RIGHTS;
cmsg->cmsg_len = CMSG_LEN(sizeof(int));
fdptr = (int *) CMSG_DATA(cmsg);
memcpy(fdptr, &file.fd, sizeof(int));
return sendmsg(sockfd, &msg, 0);
}
/*
* Receives a file descriptor from the sockfd provided. Returns the file
* descriptor as sent from sendfd(). It will return the file descriptor
* or die (literally) trying. Any synchronisation and preparation of
* state should be done external to this (we expect the other side to be
* in sendfd() in the code).
*/
struct file_t recvfd(int sockfd)
{
struct msghdr msg = {0};
struct iovec iov[1] = {0};
struct cmsghdr *cmsg;
struct file_t file = {0};
int *fdptr;
int olderrno;
union {
char buf[CMSG_SPACE(sizeof(file.fd))];
struct cmsghdr align;
} u;
/* Allocate a buffer. */
/* TODO: Make this dynamic with MSG_PEEK. */
file.name = malloc(TAG_BUFFER);
if (!file.name)
error("recvfd: failed to allocate file.tag buffer\n");
/*
* We need to "recieve" the non-ancillary data even though we don't
* plan to use it at all. Otherwise, things won't work as expected.
* See unix(7) and other well-hidden documentation.
*/
iov[0].iov_base = file.name;
iov[0].iov_len = TAG_BUFFER;
msg.msg_name = NULL;
msg.msg_namelen = 0;
msg.msg_iov = iov;
msg.msg_iovlen = 1;
msg.msg_control = u.buf;
msg.msg_controllen = sizeof(u.buf);
ssize_t ret = recvmsg(sockfd, &msg, 0);
if (ret < 0)
goto err;
cmsg = CMSG_FIRSTHDR(&msg);
if (!cmsg)
error("recvfd: got NULL from CMSG_FIRSTHDR");
if (cmsg->cmsg_level != SOL_SOCKET)
error("recvfd: expected SOL_SOCKET in cmsg: %d", cmsg->cmsg_level);
if (cmsg->cmsg_type != SCM_RIGHTS)
error("recvfd: expected SCM_RIGHTS in cmsg: %d", cmsg->cmsg_type);
if (cmsg->cmsg_len != CMSG_LEN(sizeof(int)))
error("recvfd: expected correct CMSG_LEN in cmsg: %lu", cmsg->cmsg_len);
fdptr = (int *) CMSG_DATA(cmsg);
if (!fdptr || *fdptr < 0)
error("recvfd: recieved invalid pointer");
file.fd = *fdptr;
return file;
err:
olderrno = errno;
free(file.name);
errno = olderrno;
return (struct file_t){0};
}

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// +build linux
package utils
/*
* Copyright 2016 SUSE LLC
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/*
#include <errno.h>
#include <stdlib.h>
#include "cmsg.h"
*/
import "C"
import (
"os"
"unsafe"
)
// RecvFd waits for a file descriptor to be sent over the given AF_UNIX
// socket. The file name of the remote file descriptor will be recreated
// locally (it is sent as non-auxiliary data in the same payload).
func RecvFd(socket *os.File) (*os.File, error) {
file, err := C.recvfd(C.int(socket.Fd()))
if err != nil {
return nil, err
}
defer C.free(unsafe.Pointer(file.name))
return os.NewFile(uintptr(file.fd), C.GoString(file.name)), nil
}
// SendFd sends a file descriptor over the given AF_UNIX socket. In
// addition, the file.Name() of the given file will also be sent as
// non-auxiliary data in the same payload (allowing to send contextual
// information for a file descriptor).
func SendFd(socket, file *os.File) error {
var cfile C.struct_file_t
cfile.fd = C.int(file.Fd())
cfile.name = C.CString(file.Name())
defer C.free(unsafe.Pointer(cfile.name))
_, err := C.sendfd(C.int(socket.Fd()), cfile)
return err
}

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/*
* Copyright 2016 SUSE LLC
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#pragma once
#if !defined(CMSG_H)
#define CMSG_H
#include <sys/types.h>
/* TODO: Implement this properly with MSG_PEEK. */
#define TAG_BUFFER 4096
/* This mirrors Go's (*os.File). */
struct file_t {
char *name;
int fd;
};
struct file_t recvfd(int sockfd);
ssize_t sendfd(int sockfd, struct file_t file);
#endif /* !defined(CMSG_H) */

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package utils
import (
"crypto/rand"
"encoding/hex"
"encoding/json"
"io"
"os"
"path/filepath"
"strings"
"syscall"
"unsafe"
)
const (
exitSignalOffset = 128
)
// GenerateRandomName returns a new name joined with a prefix. This size
// specified is used to truncate the randomly generated value
func GenerateRandomName(prefix string, size int) (string, error) {
id := make([]byte, 32)
if _, err := io.ReadFull(rand.Reader, id); err != nil {
return "", err
}
if size > 64 {
size = 64
}
return prefix + hex.EncodeToString(id)[:size], nil
}
// ResolveRootfs ensures that the current working directory is
// not a symlink and returns the absolute path to the rootfs
func ResolveRootfs(uncleanRootfs string) (string, error) {
rootfs, err := filepath.Abs(uncleanRootfs)
if err != nil {
return "", err
}
return filepath.EvalSymlinks(rootfs)
}
// ExitStatus returns the correct exit status for a process based on if it
// was signaled or exited cleanly
func ExitStatus(status syscall.WaitStatus) int {
if status.Signaled() {
return exitSignalOffset + int(status.Signal())
}
return status.ExitStatus()
}
// WriteJSON writes the provided struct v to w using standard json marshaling
func WriteJSON(w io.Writer, v interface{}) error {
data, err := json.Marshal(v)
if err != nil {
return err
}
_, err = w.Write(data)
return err
}
// CleanPath makes a path safe for use with filepath.Join. This is done by not
// only cleaning the path, but also (if the path is relative) adding a leading
// '/' and cleaning it (then removing the leading '/'). This ensures that a
// path resulting from prepending another path will always resolve to lexically
// be a subdirectory of the prefixed path. This is all done lexically, so paths
// that include symlinks won't be safe as a result of using CleanPath.
func CleanPath(path string) string {
// Deal with empty strings nicely.
if path == "" {
return ""
}
// Ensure that all paths are cleaned (especially problematic ones like
// "/../../../../../" which can cause lots of issues).
path = filepath.Clean(path)
// If the path isn't absolute, we need to do more processing to fix paths
// such as "../../../../<etc>/some/path". We also shouldn't convert absolute
// paths to relative ones.
if !filepath.IsAbs(path) {
path = filepath.Clean(string(os.PathSeparator) + path)
// This can't fail, as (by definition) all paths are relative to root.
path, _ = filepath.Rel(string(os.PathSeparator), path)
}
// Clean the path again for good measure.
return filepath.Clean(path)
}
// SearchLabels searches a list of key-value pairs for the provided key and
// returns the corresponding value. The pairs must be separated with '='.
func SearchLabels(labels []string, query string) string {
for _, l := range labels {
parts := strings.SplitN(l, "=", 2)
if len(parts) < 2 {
continue
}
if parts[0] == query {
return parts[1]
}
}
return ""
}
// Annotations returns the bundle path and user defined annotations from the
// libcontainer state. We need to remove the bundle because that is a label
// added by libcontainer.
func Annotations(labels []string) (bundle string, userAnnotations map[string]string) {
userAnnotations = make(map[string]string)
for _, l := range labels {
parts := strings.SplitN(l, "=", 2)
if len(parts) < 2 {
continue
}
if parts[0] == "bundle" {
bundle = parts[1]
} else {
userAnnotations[parts[0]] = parts[1]
}
}
return
}
func GetIntSize() int {
return int(unsafe.Sizeof(1))
}

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// +build !windows
package utils
import (
"io/ioutil"
"strconv"
"syscall"
)
func CloseExecFrom(minFd int) error {
fdList, err := ioutil.ReadDir("/proc/self/fd")
if err != nil {
return err
}
for _, fi := range fdList {
fd, err := strconv.Atoi(fi.Name())
if err != nil {
// ignore non-numeric file names
continue
}
if fd < minFd {
// ignore descriptors lower than our specified minimum
continue
}
// intentionally ignore errors from syscall.CloseOnExec
syscall.CloseOnExec(fd)
// the cases where this might fail are basically file descriptors that have already been closed (including and especially the one that was created when ioutil.ReadDir did the "opendir" syscall)
}
return nil
}