diff options
Diffstat (limited to 'hw/9pfs/virtio-9p-local.c')
| -rw-r--r-- | hw/9pfs/virtio-9p-local.c | 563 |
1 files changed, 563 insertions, 0 deletions
diff --git a/hw/9pfs/virtio-9p-local.c b/hw/9pfs/virtio-9p-local.c new file mode 100644 index 0000000..0a015de --- /dev/null +++ b/hw/9pfs/virtio-9p-local.c @@ -0,0 +1,563 @@ +/* + * Virtio 9p Posix callback + * + * Copyright IBM, Corp. 2010 + * + * Authors: + * Anthony Liguori <aliguori@us.ibm.com> + * + * This work is licensed under the terms of the GNU GPL, version 2. See + * the COPYING file in the top-level directory. + * + */ +#include "virtio.h" +#include "virtio-9p.h" +#include "virtio-9p-xattr.h" +#include <arpa/inet.h> +#include <pwd.h> +#include <grp.h> +#include <sys/socket.h> +#include <sys/un.h> +#include <attr/xattr.h> + + +static int local_lstat(FsContext *fs_ctx, const char *path, struct stat *stbuf) +{ + int err; + err = lstat(rpath(fs_ctx, path), stbuf); + if (err) { + return err; + } + if (fs_ctx->fs_sm == SM_MAPPED) { + /* Actual credentials are part of extended attrs */ + uid_t tmp_uid; + gid_t tmp_gid; + mode_t tmp_mode; + dev_t tmp_dev; + if (getxattr(rpath(fs_ctx, path), "user.virtfs.uid", &tmp_uid, + sizeof(uid_t)) > 0) { + stbuf->st_uid = tmp_uid; + } + if (getxattr(rpath(fs_ctx, path), "user.virtfs.gid", &tmp_gid, + sizeof(gid_t)) > 0) { + stbuf->st_gid = tmp_gid; + } + if (getxattr(rpath(fs_ctx, path), "user.virtfs.mode", &tmp_mode, + sizeof(mode_t)) > 0) { + stbuf->st_mode = tmp_mode; + } + if (getxattr(rpath(fs_ctx, path), "user.virtfs.rdev", &tmp_dev, + sizeof(dev_t)) > 0) { + stbuf->st_rdev = tmp_dev; + } + } + return err; +} + +static int local_set_xattr(const char *path, FsCred *credp) +{ + int err; + if (credp->fc_uid != -1) { + err = setxattr(path, "user.virtfs.uid", &credp->fc_uid, sizeof(uid_t), + 0); + if (err) { + return err; + } + } + if (credp->fc_gid != -1) { + err = setxattr(path, "user.virtfs.gid", &credp->fc_gid, sizeof(gid_t), + 0); + if (err) { + return err; + } + } + if (credp->fc_mode != -1) { + err = setxattr(path, "user.virtfs.mode", &credp->fc_mode, + sizeof(mode_t), 0); + if (err) { + return err; + } + } + if (credp->fc_rdev != -1) { + err = setxattr(path, "user.virtfs.rdev", &credp->fc_rdev, + sizeof(dev_t), 0); + if (err) { + return err; + } + } + return 0; +} + +static int local_post_create_passthrough(FsContext *fs_ctx, const char *path, + FsCred *credp) +{ + if (chmod(rpath(fs_ctx, path), credp->fc_mode & 07777) < 0) { + return -1; + } + if (lchown(rpath(fs_ctx, path), credp->fc_uid, credp->fc_gid) < 0) { + /* + * If we fail to change ownership and if we are + * using security model none. Ignore the error + */ + if (fs_ctx->fs_sm != SM_NONE) { + return -1; + } + } + return 0; +} + +static ssize_t local_readlink(FsContext *fs_ctx, const char *path, + char *buf, size_t bufsz) +{ + ssize_t tsize = -1; + if (fs_ctx->fs_sm == SM_MAPPED) { + int fd; + fd = open(rpath(fs_ctx, path), O_RDONLY); + if (fd == -1) { + return -1; + } + do { + tsize = read(fd, (void *)buf, bufsz); + } while (tsize == -1 && errno == EINTR); + close(fd); + return tsize; + } else if ((fs_ctx->fs_sm == SM_PASSTHROUGH) || + (fs_ctx->fs_sm == SM_NONE)) { + tsize = readlink(rpath(fs_ctx, path), buf, bufsz); + } + return tsize; +} + +static int local_close(FsContext *ctx, int fd) +{ + return close(fd); +} + +static int local_closedir(FsContext *ctx, DIR *dir) +{ + return closedir(dir); +} + +static int local_open(FsContext *ctx, const char *path, int flags) +{ + return open(rpath(ctx, path), flags); +} + +static DIR *local_opendir(FsContext *ctx, const char *path) +{ + return opendir(rpath(ctx, path)); +} + +static void local_rewinddir(FsContext *ctx, DIR *dir) +{ + return rewinddir(dir); +} + +static off_t local_telldir(FsContext *ctx, DIR *dir) +{ + return telldir(dir); +} + +static struct dirent *local_readdir(FsContext *ctx, DIR *dir) +{ + return readdir(dir); +} + +static void local_seekdir(FsContext *ctx, DIR *dir, off_t off) +{ + return seekdir(dir, off); +} + +static ssize_t local_preadv(FsContext *ctx, int fd, const struct iovec *iov, + int iovcnt, off_t offset) +{ +#ifdef CONFIG_PREADV + return preadv(fd, iov, iovcnt, offset); +#else + int err = lseek(fd, offset, SEEK_SET); + if (err == -1) { + return err; + } else { + return readv(fd, iov, iovcnt); + } +#endif +} + +static ssize_t local_pwritev(FsContext *ctx, int fd, const struct iovec *iov, + int iovcnt, off_t offset) +{ +#ifdef CONFIG_PREADV + return pwritev(fd, iov, iovcnt, offset); +#else + int err = lseek(fd, offset, SEEK_SET); + if (err == -1) { + return err; + } else { + return writev(fd, iov, iovcnt); + } +#endif +} + +static int local_chmod(FsContext *fs_ctx, const char *path, FsCred *credp) +{ + if (fs_ctx->fs_sm == SM_MAPPED) { + return local_set_xattr(rpath(fs_ctx, path), credp); + } else if ((fs_ctx->fs_sm == SM_PASSTHROUGH) || + (fs_ctx->fs_sm == SM_NONE)) { + return chmod(rpath(fs_ctx, path), credp->fc_mode); + } + return -1; +} + +static int local_mknod(FsContext *fs_ctx, const char *path, FsCred *credp) +{ + int err = -1; + int serrno = 0; + + /* Determine the security model */ + if (fs_ctx->fs_sm == SM_MAPPED) { + err = mknod(rpath(fs_ctx, path), SM_LOCAL_MODE_BITS|S_IFREG, 0); + if (err == -1) { + return err; + } + local_set_xattr(rpath(fs_ctx, path), credp); + if (err == -1) { + serrno = errno; + goto err_end; + } + } else if ((fs_ctx->fs_sm == SM_PASSTHROUGH) || + (fs_ctx->fs_sm == SM_NONE)) { + err = mknod(rpath(fs_ctx, path), credp->fc_mode, credp->fc_rdev); + if (err == -1) { + return err; + } + err = local_post_create_passthrough(fs_ctx, path, credp); + if (err == -1) { + serrno = errno; + goto err_end; + } + } + return err; + +err_end: + remove(rpath(fs_ctx, path)); + errno = serrno; + return err; +} + +static int local_mkdir(FsContext *fs_ctx, const char *path, FsCred *credp) +{ + int err = -1; + int serrno = 0; + + /* Determine the security model */ + if (fs_ctx->fs_sm == SM_MAPPED) { + err = mkdir(rpath(fs_ctx, path), SM_LOCAL_DIR_MODE_BITS); + if (err == -1) { + return err; + } + credp->fc_mode = credp->fc_mode|S_IFDIR; + err = local_set_xattr(rpath(fs_ctx, path), credp); + if (err == -1) { + serrno = errno; + goto err_end; + } + } else if ((fs_ctx->fs_sm == SM_PASSTHROUGH) || + (fs_ctx->fs_sm == SM_NONE)) { + err = mkdir(rpath(fs_ctx, path), credp->fc_mode); + if (err == -1) { + return err; + } + err = local_post_create_passthrough(fs_ctx, path, credp); + if (err == -1) { + serrno = errno; + goto err_end; + } + } + return err; + +err_end: + remove(rpath(fs_ctx, path)); + errno = serrno; + return err; +} + +static int local_fstat(FsContext *fs_ctx, int fd, struct stat *stbuf) +{ + int err; + err = fstat(fd, stbuf); + if (err) { + return err; + } + if (fs_ctx->fs_sm == SM_MAPPED) { + /* Actual credentials are part of extended attrs */ + uid_t tmp_uid; + gid_t tmp_gid; + mode_t tmp_mode; + dev_t tmp_dev; + + if (fgetxattr(fd, "user.virtfs.uid", &tmp_uid, sizeof(uid_t)) > 0) { + stbuf->st_uid = tmp_uid; + } + if (fgetxattr(fd, "user.virtfs.gid", &tmp_gid, sizeof(gid_t)) > 0) { + stbuf->st_gid = tmp_gid; + } + if (fgetxattr(fd, "user.virtfs.mode", &tmp_mode, sizeof(mode_t)) > 0) { + stbuf->st_mode = tmp_mode; + } + if (fgetxattr(fd, "user.virtfs.rdev", &tmp_dev, sizeof(dev_t)) > 0) { + stbuf->st_rdev = tmp_dev; + } + } + return err; +} + +static int local_open2(FsContext *fs_ctx, const char *path, int flags, + FsCred *credp) +{ + int fd = -1; + int err = -1; + int serrno = 0; + + /* Determine the security model */ + if (fs_ctx->fs_sm == SM_MAPPED) { + fd = open(rpath(fs_ctx, path), flags, SM_LOCAL_MODE_BITS); + if (fd == -1) { + return fd; + } + credp->fc_mode = credp->fc_mode|S_IFREG; + /* Set cleint credentials in xattr */ + err = local_set_xattr(rpath(fs_ctx, path), credp); + if (err == -1) { + serrno = errno; + goto err_end; + } + } else if ((fs_ctx->fs_sm == SM_PASSTHROUGH) || + (fs_ctx->fs_sm == SM_NONE)) { + fd = open(rpath(fs_ctx, path), flags, credp->fc_mode); + if (fd == -1) { + return fd; + } + err = local_post_create_passthrough(fs_ctx, path, credp); + if (err == -1) { + serrno = errno; + goto err_end; + } + } + return fd; + +err_end: + close(fd); + remove(rpath(fs_ctx, path)); + errno = serrno; + return err; +} + + +static int local_symlink(FsContext *fs_ctx, const char *oldpath, + const char *newpath, FsCred *credp) +{ + int err = -1; + int serrno = 0; + + /* Determine the security model */ + if (fs_ctx->fs_sm == SM_MAPPED) { + int fd; + ssize_t oldpath_size, write_size; + fd = open(rpath(fs_ctx, newpath), O_CREAT|O_EXCL|O_RDWR, + SM_LOCAL_MODE_BITS); + if (fd == -1) { + return fd; + } + /* Write the oldpath (target) to the file. */ + oldpath_size = strlen(oldpath); + do { + write_size = write(fd, (void *)oldpath, oldpath_size); + } while (write_size == -1 && errno == EINTR); + + if (write_size != oldpath_size) { + serrno = errno; + close(fd); + err = -1; + goto err_end; + } + close(fd); + /* Set cleint credentials in symlink's xattr */ + credp->fc_mode = credp->fc_mode|S_IFLNK; + err = local_set_xattr(rpath(fs_ctx, newpath), credp); + if (err == -1) { + serrno = errno; + goto err_end; + } + } else if ((fs_ctx->fs_sm == SM_PASSTHROUGH) || + (fs_ctx->fs_sm == SM_NONE)) { + err = symlink(oldpath, rpath(fs_ctx, newpath)); + if (err) { + return err; + } + err = lchown(rpath(fs_ctx, newpath), credp->fc_uid, credp->fc_gid); + if (err == -1) { + /* + * If we fail to change ownership and if we are + * using security model none. Ignore the error + */ + if (fs_ctx->fs_sm != SM_NONE) { + serrno = errno; + goto err_end; + } else + err = 0; + } + } + return err; + +err_end: + remove(rpath(fs_ctx, newpath)); + errno = serrno; + return err; +} + +static int local_link(FsContext *ctx, const char *oldpath, const char *newpath) +{ + char *tmp = qemu_strdup(rpath(ctx, oldpath)); + int err, serrno = 0; + + if (tmp == NULL) { + return -ENOMEM; + } + + err = link(tmp, rpath(ctx, newpath)); + if (err == -1) { + serrno = errno; + } + + qemu_free(tmp); + + if (err == -1) { + errno = serrno; + } + + return err; +} + +static int local_truncate(FsContext *ctx, const char *path, off_t size) +{ + return truncate(rpath(ctx, path), size); +} + +static int local_rename(FsContext *ctx, const char *oldpath, + const char *newpath) +{ + char *tmp; + int err; + + tmp = qemu_strdup(rpath(ctx, oldpath)); + + err = rename(tmp, rpath(ctx, newpath)); + if (err == -1) { + int serrno = errno; + qemu_free(tmp); + errno = serrno; + } else { + qemu_free(tmp); + } + + return err; + +} + +static int local_chown(FsContext *fs_ctx, const char *path, FsCred *credp) +{ + if ((credp->fc_uid == -1 && credp->fc_gid == -1) || + (fs_ctx->fs_sm == SM_PASSTHROUGH)) { + return lchown(rpath(fs_ctx, path), credp->fc_uid, credp->fc_gid); + } else if (fs_ctx->fs_sm == SM_MAPPED) { + return local_set_xattr(rpath(fs_ctx, path), credp); + } else if ((fs_ctx->fs_sm == SM_PASSTHROUGH) || + (fs_ctx->fs_sm == SM_NONE)) { + return lchown(rpath(fs_ctx, path), credp->fc_uid, credp->fc_gid); + } + return -1; +} + +static int local_utimensat(FsContext *s, const char *path, + const struct timespec *buf) +{ + return qemu_utimensat(AT_FDCWD, rpath(s, path), buf, AT_SYMLINK_NOFOLLOW); +} + +static int local_remove(FsContext *ctx, const char *path) +{ + return remove(rpath(ctx, path)); +} + +static int local_fsync(FsContext *ctx, int fd, int datasync) +{ + if (datasync) { + return qemu_fdatasync(fd); + } else { + return fsync(fd); + } +} + +static int local_statfs(FsContext *s, const char *path, struct statfs *stbuf) +{ + return statfs(rpath(s, path), stbuf); +} + +static ssize_t local_lgetxattr(FsContext *ctx, const char *path, + const char *name, void *value, size_t size) +{ + return v9fs_get_xattr(ctx, path, name, value, size); +} + +static ssize_t local_llistxattr(FsContext *ctx, const char *path, + void *value, size_t size) +{ + return v9fs_list_xattr(ctx, path, value, size); +} + +static int local_lsetxattr(FsContext *ctx, const char *path, const char *name, + void *value, size_t size, int flags) +{ + return v9fs_set_xattr(ctx, path, name, value, size, flags); +} + +static int local_lremovexattr(FsContext *ctx, + const char *path, const char *name) +{ + return v9fs_remove_xattr(ctx, path, name); +} + + +FileOperations local_ops = { + .lstat = local_lstat, + .readlink = local_readlink, + .close = local_close, + .closedir = local_closedir, + .open = local_open, + .opendir = local_opendir, + .rewinddir = local_rewinddir, + .telldir = local_telldir, + .readdir = local_readdir, + .seekdir = local_seekdir, + .preadv = local_preadv, + .pwritev = local_pwritev, + .chmod = local_chmod, + .mknod = local_mknod, + .mkdir = local_mkdir, + .fstat = local_fstat, + .open2 = local_open2, + .symlink = local_symlink, + .link = local_link, + .truncate = local_truncate, + .rename = local_rename, + .chown = local_chown, + .utimensat = local_utimensat, + .remove = local_remove, + .fsync = local_fsync, + .statfs = local_statfs, + .lgetxattr = local_lgetxattr, + .llistxattr = local_llistxattr, + .lsetxattr = local_lsetxattr, + .lremovexattr = local_lremovexattr, +}; |