root / hw / virtio-9p-local.c @ 879c2813
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/*
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* Virtio 9p Posix callback
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*
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* Copyright IBM, Corp. 2010
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*
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* Authors:
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* Anthony Liguori <aliguori@us.ibm.com>
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*
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* This work is licensed under the terms of the GNU GPL, version 2. See
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* the COPYING file in the top-level directory.
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*
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*/
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#include "virtio.h" |
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#include "virtio-9p.h" |
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#include <arpa/inet.h> |
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#include <pwd.h> |
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#include <grp.h> |
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#include <sys/socket.h> |
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#include <sys/un.h> |
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#include <attr/xattr.h> |
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|
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static const char *rpath(FsContext *ctx, const char *path) |
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{
|
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/* FIXME: so wrong... */
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static char buffer[4096]; |
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snprintf(buffer, sizeof(buffer), "%s/%s", ctx->fs_root, path); |
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return buffer;
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} |
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|
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|
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static int local_lstat(FsContext *fs_ctx, const char *path, struct stat *stbuf) |
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{
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int err;
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err = lstat(rpath(fs_ctx, path), stbuf); |
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if (err) {
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return err;
|
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} |
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if (fs_ctx->fs_sm == SM_MAPPED) {
|
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/* Actual credentials are part of extended attrs */
|
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uid_t tmp_uid; |
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gid_t tmp_gid; |
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mode_t tmp_mode; |
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dev_t tmp_dev; |
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if (getxattr(rpath(fs_ctx, path), "user.virtfs.uid", &tmp_uid, |
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sizeof(uid_t)) > 0) { |
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stbuf->st_uid = tmp_uid; |
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} |
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if (getxattr(rpath(fs_ctx, path), "user.virtfs.gid", &tmp_gid, |
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sizeof(gid_t)) > 0) { |
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stbuf->st_gid = tmp_gid; |
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} |
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if (getxattr(rpath(fs_ctx, path), "user.virtfs.mode", &tmp_mode, |
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sizeof(mode_t)) > 0) { |
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stbuf->st_mode = tmp_mode; |
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} |
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if (getxattr(rpath(fs_ctx, path), "user.virtfs.rdev", &tmp_dev, |
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sizeof(dev_t)) > 0) { |
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stbuf->st_rdev = tmp_dev; |
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} |
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} |
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return err;
|
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} |
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|
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static int local_set_xattr(const char *path, FsCred *credp) |
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{
|
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int err;
|
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if (credp->fc_uid != -1) { |
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err = setxattr(path, "user.virtfs.uid", &credp->fc_uid, sizeof(uid_t), |
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0);
|
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if (err) {
|
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return err;
|
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} |
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} |
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if (credp->fc_gid != -1) { |
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err = setxattr(path, "user.virtfs.gid", &credp->fc_gid, sizeof(gid_t), |
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0);
|
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if (err) {
|
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return err;
|
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} |
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} |
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if (credp->fc_mode != -1) { |
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err = setxattr(path, "user.virtfs.mode", &credp->fc_mode,
|
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sizeof(mode_t), 0); |
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if (err) {
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return err;
|
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} |
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} |
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if (credp->fc_rdev != -1) { |
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err = setxattr(path, "user.virtfs.rdev", &credp->fc_rdev,
|
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sizeof(dev_t), 0); |
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if (err) {
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return err;
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} |
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} |
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return 0; |
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} |
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|
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static int local_post_create_passthrough(FsContext *fs_ctx, const char *path, |
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FsCred *credp) |
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{
|
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if (chmod(rpath(fs_ctx, path), credp->fc_mode & 07777) < 0) { |
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return -1; |
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} |
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if (chown(rpath(fs_ctx, path), credp->fc_uid, credp->fc_gid) < 0) { |
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return -1; |
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} |
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return 0; |
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} |
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|
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static ssize_t local_readlink(FsContext *fs_ctx, const char *path, |
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char *buf, size_t bufsz)
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{
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ssize_t tsize = -1;
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if (fs_ctx->fs_sm == SM_MAPPED) {
|
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int fd;
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fd = open(rpath(fs_ctx, path), O_RDONLY); |
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if (fd == -1) { |
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return -1; |
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} |
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do {
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tsize = read(fd, (void *)buf, bufsz);
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} while (tsize == -1 && errno == EINTR); |
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close(fd); |
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return tsize;
|
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} else if (fs_ctx->fs_sm == SM_PASSTHROUGH) { |
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tsize = readlink(rpath(fs_ctx, path), buf, bufsz); |
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} |
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return tsize;
|
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} |
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|
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static int local_close(FsContext *ctx, int fd) |
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{
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return close(fd);
|
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} |
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|
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static int local_closedir(FsContext *ctx, DIR *dir) |
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{
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return closedir(dir);
|
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} |
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|
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static int local_open(FsContext *ctx, const char *path, int flags) |
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{
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return open(rpath(ctx, path), flags);
|
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} |
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|
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static DIR *local_opendir(FsContext *ctx, const char *path) |
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{
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return opendir(rpath(ctx, path));
|
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} |
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|
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static void local_rewinddir(FsContext *ctx, DIR *dir) |
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{
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return rewinddir(dir);
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} |
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|
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static off_t local_telldir(FsContext *ctx, DIR *dir)
|
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{
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return telldir(dir);
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} |
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|
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static struct dirent *local_readdir(FsContext *ctx, DIR *dir) |
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{
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return readdir(dir);
|
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} |
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|
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static void local_seekdir(FsContext *ctx, DIR *dir, off_t off) |
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{
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return seekdir(dir, off);
|
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} |
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|
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static ssize_t local_readv(FsContext *ctx, int fd, const struct iovec *iov, |
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int iovcnt)
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{
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return readv(fd, iov, iovcnt);
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} |
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|
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static off_t local_lseek(FsContext *ctx, int fd, off_t offset, int whence) |
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{
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return lseek(fd, offset, whence);
|
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} |
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|
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static ssize_t local_writev(FsContext *ctx, int fd, const struct iovec *iov, |
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int iovcnt)
|
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{
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return writev(fd, iov, iovcnt);
|
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} |
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|
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static int local_chmod(FsContext *fs_ctx, const char *path, FsCred *credp) |
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{
|
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if (fs_ctx->fs_sm == SM_MAPPED) {
|
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return local_set_xattr(rpath(fs_ctx, path), credp);
|
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} else if (fs_ctx->fs_sm == SM_PASSTHROUGH) { |
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return chmod(rpath(fs_ctx, path), credp->fc_mode);
|
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} |
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return -1; |
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} |
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|
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static int local_mknod(FsContext *ctx, const char *path, mode_t mode, dev_t dev) |
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{
|
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return mknod(rpath(ctx, path), mode, dev);
|
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} |
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|
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static int local_mksock(FsContext *ctx2, const char *path) |
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{
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struct sockaddr_un addr;
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int s;
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|
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addr.sun_family = AF_UNIX; |
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snprintf(addr.sun_path, 108, "%s", rpath(ctx2, path)); |
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|
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s = socket(PF_UNIX, SOCK_STREAM, 0);
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if (s == -1) { |
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return -1; |
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} |
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|
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if (bind(s, (struct sockaddr *)&addr, sizeof(addr))) { |
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close(s); |
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return -1; |
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} |
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|
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close(s); |
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return 0; |
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} |
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|
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static int local_mkdir(FsContext *fs_ctx, const char *path, FsCred *credp) |
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{
|
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int err = -1; |
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int serrno = 0; |
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|
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/* Determine the security model */
|
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if (fs_ctx->fs_sm == SM_MAPPED) {
|
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err = mkdir(rpath(fs_ctx, path), SM_LOCAL_DIR_MODE_BITS); |
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if (err == -1) { |
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return err;
|
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} |
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credp->fc_mode = credp->fc_mode|S_IFDIR; |
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err = local_set_xattr(rpath(fs_ctx, path), credp); |
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if (err == -1) { |
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serrno = errno; |
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goto err_end;
|
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} |
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} else if (fs_ctx->fs_sm == SM_PASSTHROUGH) { |
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err = mkdir(rpath(fs_ctx, path), credp->fc_mode); |
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if (err == -1) { |
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return err;
|
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} |
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err = local_post_create_passthrough(fs_ctx, path, credp); |
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if (err == -1) { |
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serrno = errno; |
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goto err_end;
|
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} |
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} |
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return err;
|
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|
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err_end:
|
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remove(rpath(fs_ctx, path)); |
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errno = serrno; |
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return err;
|
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} |
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|
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static int local_fstat(FsContext *fs_ctx, int fd, struct stat *stbuf) |
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{
|
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int err;
|
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err = fstat(fd, stbuf); |
| 265 |
if (err) {
|
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return err;
|
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} |
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if (fs_ctx->fs_sm == SM_MAPPED) {
|
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/* Actual credentials are part of extended attrs */
|
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uid_t tmp_uid; |
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gid_t tmp_gid; |
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mode_t tmp_mode; |
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dev_t tmp_dev; |
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|
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if (fgetxattr(fd, "user.virtfs.uid", &tmp_uid, sizeof(uid_t)) > 0) { |
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stbuf->st_uid = tmp_uid; |
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} |
| 278 |
if (fgetxattr(fd, "user.virtfs.gid", &tmp_gid, sizeof(gid_t)) > 0) { |
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stbuf->st_gid = tmp_gid; |
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} |
| 281 |
if (fgetxattr(fd, "user.virtfs.mode", &tmp_mode, sizeof(mode_t)) > 0) { |
| 282 |
stbuf->st_mode = tmp_mode; |
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} |
| 284 |
if (fgetxattr(fd, "user.virtfs.rdev", &tmp_dev, sizeof(dev_t)) > 0) { |
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stbuf->st_rdev = tmp_dev; |
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} |
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} |
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return err;
|
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} |
| 290 |
|
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static int local_open2(FsContext *fs_ctx, const char *path, int flags, |
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FsCred *credp) |
| 293 |
{
|
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int fd = -1; |
| 295 |
int err = -1; |
| 296 |
int serrno = 0; |
| 297 |
|
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/* Determine the security model */
|
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if (fs_ctx->fs_sm == SM_MAPPED) {
|
| 300 |
fd = open(rpath(fs_ctx, path), flags, SM_LOCAL_MODE_BITS); |
| 301 |
if (fd == -1) { |
| 302 |
return fd;
|
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} |
| 304 |
credp->fc_mode = credp->fc_mode|S_IFREG; |
| 305 |
/* Set cleint credentials in xattr */
|
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err = local_set_xattr(rpath(fs_ctx, path), credp); |
| 307 |
if (err == -1) { |
| 308 |
serrno = errno; |
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goto err_end;
|
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} |
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} else if (fs_ctx->fs_sm == SM_PASSTHROUGH) { |
| 312 |
fd = open(rpath(fs_ctx, path), flags, credp->fc_mode); |
| 313 |
if (fd == -1) { |
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return fd;
|
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} |
| 316 |
err = local_post_create_passthrough(fs_ctx, path, credp); |
| 317 |
if (err == -1) { |
| 318 |
serrno = errno; |
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goto err_end;
|
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} |
| 321 |
} |
| 322 |
return fd;
|
| 323 |
|
| 324 |
err_end:
|
| 325 |
close(fd); |
| 326 |
remove(rpath(fs_ctx, path)); |
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errno = serrno; |
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return err;
|
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} |
| 330 |
|
| 331 |
|
| 332 |
static int local_symlink(FsContext *fs_ctx, const char *oldpath, |
| 333 |
const char *newpath, FsCred *credp) |
| 334 |
{
|
| 335 |
int err = -1; |
| 336 |
int serrno = 0; |
| 337 |
|
| 338 |
/* Determine the security model */
|
| 339 |
if (fs_ctx->fs_sm == SM_MAPPED) {
|
| 340 |
int fd;
|
| 341 |
ssize_t oldpath_size, write_size; |
| 342 |
fd = open(rpath(fs_ctx, newpath), O_CREAT|O_EXCL|O_RDWR, |
| 343 |
SM_LOCAL_MODE_BITS); |
| 344 |
if (fd == -1) { |
| 345 |
return fd;
|
| 346 |
} |
| 347 |
/* Write the oldpath (target) to the file. */
|
| 348 |
oldpath_size = strlen(oldpath) + 1;
|
| 349 |
do {
|
| 350 |
write_size = write(fd, (void *)oldpath, oldpath_size);
|
| 351 |
} while (write_size == -1 && errno == EINTR); |
| 352 |
|
| 353 |
if (write_size != oldpath_size) {
|
| 354 |
serrno = errno; |
| 355 |
close(fd); |
| 356 |
err = -1;
|
| 357 |
goto err_end;
|
| 358 |
} |
| 359 |
close(fd); |
| 360 |
/* Set cleint credentials in symlink's xattr */
|
| 361 |
credp->fc_mode = credp->fc_mode|S_IFLNK; |
| 362 |
err = local_set_xattr(rpath(fs_ctx, newpath), credp); |
| 363 |
if (err == -1) { |
| 364 |
serrno = errno; |
| 365 |
goto err_end;
|
| 366 |
} |
| 367 |
} else if (fs_ctx->fs_sm == SM_PASSTHROUGH) { |
| 368 |
err = symlink(oldpath, rpath(fs_ctx, newpath)); |
| 369 |
if (err) {
|
| 370 |
return err;
|
| 371 |
} |
| 372 |
err = lchown(rpath(fs_ctx, newpath), credp->fc_uid, credp->fc_gid); |
| 373 |
if (err == -1) { |
| 374 |
serrno = errno; |
| 375 |
goto err_end;
|
| 376 |
} |
| 377 |
} |
| 378 |
return err;
|
| 379 |
|
| 380 |
err_end:
|
| 381 |
remove(rpath(fs_ctx, newpath)); |
| 382 |
errno = serrno; |
| 383 |
return err;
|
| 384 |
} |
| 385 |
|
| 386 |
static int local_link(FsContext *ctx, const char *oldpath, const char *newpath) |
| 387 |
{
|
| 388 |
char *tmp = qemu_strdup(rpath(ctx, oldpath));
|
| 389 |
int err, serrno = 0; |
| 390 |
|
| 391 |
if (tmp == NULL) { |
| 392 |
return -ENOMEM;
|
| 393 |
} |
| 394 |
|
| 395 |
err = link(tmp, rpath(ctx, newpath)); |
| 396 |
if (err == -1) { |
| 397 |
serrno = errno; |
| 398 |
} |
| 399 |
|
| 400 |
qemu_free(tmp); |
| 401 |
|
| 402 |
if (err == -1) { |
| 403 |
errno = serrno; |
| 404 |
} |
| 405 |
|
| 406 |
return err;
|
| 407 |
} |
| 408 |
|
| 409 |
static int local_truncate(FsContext *ctx, const char *path, off_t size) |
| 410 |
{
|
| 411 |
return truncate(rpath(ctx, path), size);
|
| 412 |
} |
| 413 |
|
| 414 |
static int local_rename(FsContext *ctx, const char *oldpath, |
| 415 |
const char *newpath) |
| 416 |
{
|
| 417 |
char *tmp;
|
| 418 |
int err;
|
| 419 |
|
| 420 |
tmp = qemu_strdup(rpath(ctx, oldpath)); |
| 421 |
if (tmp == NULL) { |
| 422 |
return -1; |
| 423 |
} |
| 424 |
|
| 425 |
err = rename(tmp, rpath(ctx, newpath)); |
| 426 |
if (err == -1) { |
| 427 |
int serrno = errno;
|
| 428 |
qemu_free(tmp); |
| 429 |
errno = serrno; |
| 430 |
} else {
|
| 431 |
qemu_free(tmp); |
| 432 |
} |
| 433 |
|
| 434 |
return err;
|
| 435 |
|
| 436 |
} |
| 437 |
|
| 438 |
static int local_chown(FsContext *fs_ctx, const char *path, FsCred *credp) |
| 439 |
{
|
| 440 |
if (fs_ctx->fs_sm == SM_MAPPED) {
|
| 441 |
return local_set_xattr(rpath(fs_ctx, path), credp);
|
| 442 |
} else if (fs_ctx->fs_sm == SM_PASSTHROUGH) { |
| 443 |
return lchown(rpath(fs_ctx, path), credp->fc_uid, credp->fc_gid);
|
| 444 |
} |
| 445 |
return -1; |
| 446 |
} |
| 447 |
|
| 448 |
static int local_utime(FsContext *ctx, const char *path, |
| 449 |
const struct utimbuf *buf) |
| 450 |
{
|
| 451 |
return utime(rpath(ctx, path), buf);
|
| 452 |
} |
| 453 |
|
| 454 |
static int local_remove(FsContext *ctx, const char *path) |
| 455 |
{
|
| 456 |
return remove(rpath(ctx, path));
|
| 457 |
} |
| 458 |
|
| 459 |
static int local_fsync(FsContext *ctx, int fd) |
| 460 |
{
|
| 461 |
return fsync(fd);
|
| 462 |
} |
| 463 |
|
| 464 |
FileOperations local_ops = {
|
| 465 |
.lstat = local_lstat, |
| 466 |
.readlink = local_readlink, |
| 467 |
.close = local_close, |
| 468 |
.closedir = local_closedir, |
| 469 |
.open = local_open, |
| 470 |
.opendir = local_opendir, |
| 471 |
.rewinddir = local_rewinddir, |
| 472 |
.telldir = local_telldir, |
| 473 |
.readdir = local_readdir, |
| 474 |
.seekdir = local_seekdir, |
| 475 |
.readv = local_readv, |
| 476 |
.lseek = local_lseek, |
| 477 |
.writev = local_writev, |
| 478 |
.chmod = local_chmod, |
| 479 |
.mknod = local_mknod, |
| 480 |
.mksock = local_mksock, |
| 481 |
.mkdir = local_mkdir, |
| 482 |
.fstat = local_fstat, |
| 483 |
.open2 = local_open2, |
| 484 |
.symlink = local_symlink, |
| 485 |
.link = local_link, |
| 486 |
.truncate = local_truncate, |
| 487 |
.rename = local_rename, |
| 488 |
.chown = local_chown, |
| 489 |
.utime = local_utime, |
| 490 |
.remove = local_remove, |
| 491 |
.fsync = local_fsync, |
| 492 |
}; |