| /* |
| * 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 "hw/virtio/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 "qemu/xattr.h" |
| #include <libgen.h> |
| #include <linux/fs.h> |
| #ifdef CONFIG_LINUX_MAGIC_H |
| #include <linux/magic.h> |
| #endif |
| #include <sys/ioctl.h> |
| |
| #ifndef XFS_SUPER_MAGIC |
| #define XFS_SUPER_MAGIC 0x58465342 |
| #endif |
| #ifndef EXT2_SUPER_MAGIC |
| #define EXT2_SUPER_MAGIC 0xEF53 |
| #endif |
| #ifndef REISERFS_SUPER_MAGIC |
| #define REISERFS_SUPER_MAGIC 0x52654973 |
| #endif |
| #ifndef BTRFS_SUPER_MAGIC |
| #define BTRFS_SUPER_MAGIC 0x9123683E |
| #endif |
| |
| #define VIRTFS_META_DIR ".virtfs_metadata" |
| |
| static const char *local_mapped_attr_path(FsContext *ctx, |
| const char *path, char *buffer) |
| { |
| char *dir_name; |
| char *tmp_path = g_strdup(path); |
| char *base_name = basename(tmp_path); |
| |
| /* NULL terminate the directory */ |
| dir_name = tmp_path; |
| *(base_name - 1) = '\0'; |
| |
| snprintf(buffer, PATH_MAX, "%s/%s/%s/%s", |
| ctx->fs_root, dir_name, VIRTFS_META_DIR, base_name); |
| g_free(tmp_path); |
| return buffer; |
| } |
| |
| static FILE *local_fopen(const char *path, const char *mode) |
| { |
| int fd, o_mode = 0; |
| FILE *fp; |
| int flags = O_NOFOLLOW; |
| /* |
| * only supports two modes |
| */ |
| if (mode[0] == 'r') { |
| flags |= O_RDONLY; |
| } else if (mode[0] == 'w') { |
| flags |= O_WRONLY | O_TRUNC | O_CREAT; |
| o_mode = S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH; |
| } else { |
| return NULL; |
| } |
| fd = open(path, flags, o_mode); |
| if (fd == -1) { |
| return NULL; |
| } |
| fp = fdopen(fd, mode); |
| if (!fp) { |
| close(fd); |
| } |
| return fp; |
| } |
| |
| #define ATTR_MAX 100 |
| static void local_mapped_file_attr(FsContext *ctx, const char *path, |
| struct stat *stbuf) |
| { |
| FILE *fp; |
| char buf[ATTR_MAX]; |
| char attr_path[PATH_MAX]; |
| |
| local_mapped_attr_path(ctx, path, attr_path); |
| fp = local_fopen(attr_path, "r"); |
| if (!fp) { |
| return; |
| } |
| memset(buf, 0, ATTR_MAX); |
| while (fgets(buf, ATTR_MAX, fp)) { |
| if (!strncmp(buf, "virtfs.uid", 10)) { |
| stbuf->st_uid = atoi(buf+11); |
| } else if (!strncmp(buf, "virtfs.gid", 10)) { |
| stbuf->st_gid = atoi(buf+11); |
| } else if (!strncmp(buf, "virtfs.mode", 11)) { |
| stbuf->st_mode = atoi(buf+12); |
| } else if (!strncmp(buf, "virtfs.rdev", 11)) { |
| stbuf->st_rdev = atoi(buf+12); |
| } |
| memset(buf, 0, ATTR_MAX); |
| } |
| fclose(fp); |
| } |
| |
| static int local_lstat(FsContext *fs_ctx, V9fsPath *fs_path, struct stat *stbuf) |
| { |
| int err; |
| char buffer[PATH_MAX]; |
| char *path = fs_path->data; |
| |
| err = lstat(rpath(fs_ctx, path, buffer), stbuf); |
| if (err) { |
| return err; |
| } |
| if (fs_ctx->export_flags & V9FS_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, buffer), "user.virtfs.uid", &tmp_uid, |
| sizeof(uid_t)) > 0) { |
| stbuf->st_uid = tmp_uid; |
| } |
| if (getxattr(rpath(fs_ctx, path, buffer), "user.virtfs.gid", &tmp_gid, |
| sizeof(gid_t)) > 0) { |
| stbuf->st_gid = tmp_gid; |
| } |
| if (getxattr(rpath(fs_ctx, path, buffer), "user.virtfs.mode", |
| &tmp_mode, sizeof(mode_t)) > 0) { |
| stbuf->st_mode = tmp_mode; |
| } |
| if (getxattr(rpath(fs_ctx, path, buffer), "user.virtfs.rdev", &tmp_dev, |
| sizeof(dev_t)) > 0) { |
| stbuf->st_rdev = tmp_dev; |
| } |
| } else if (fs_ctx->export_flags & V9FS_SM_MAPPED_FILE) { |
| local_mapped_file_attr(fs_ctx, path, stbuf); |
| } |
| return err; |
| } |
| |
| static int local_create_mapped_attr_dir(FsContext *ctx, const char *path) |
| { |
| int err; |
| char attr_dir[PATH_MAX]; |
| char *tmp_path = g_strdup(path); |
| |
| snprintf(attr_dir, PATH_MAX, "%s/%s/%s", |
| ctx->fs_root, dirname(tmp_path), VIRTFS_META_DIR); |
| |
| err = mkdir(attr_dir, 0700); |
| if (err < 0 && errno == EEXIST) { |
| err = 0; |
| } |
| g_free(tmp_path); |
| return err; |
| } |
| |
| static int local_set_mapped_file_attr(FsContext *ctx, |
| const char *path, FsCred *credp) |
| { |
| FILE *fp; |
| int ret = 0; |
| char buf[ATTR_MAX]; |
| char attr_path[PATH_MAX]; |
| int uid = -1, gid = -1, mode = -1, rdev = -1; |
| |
| fp = local_fopen(local_mapped_attr_path(ctx, path, attr_path), "r"); |
| if (!fp) { |
| goto create_map_file; |
| } |
| memset(buf, 0, ATTR_MAX); |
| while (fgets(buf, ATTR_MAX, fp)) { |
| if (!strncmp(buf, "virtfs.uid", 10)) { |
| uid = atoi(buf+11); |
| } else if (!strncmp(buf, "virtfs.gid", 10)) { |
| gid = atoi(buf+11); |
| } else if (!strncmp(buf, "virtfs.mode", 11)) { |
| mode = atoi(buf+12); |
| } else if (!strncmp(buf, "virtfs.rdev", 11)) { |
| rdev = atoi(buf+12); |
| } |
| memset(buf, 0, ATTR_MAX); |
| } |
| fclose(fp); |
| goto update_map_file; |
| |
| create_map_file: |
| ret = local_create_mapped_attr_dir(ctx, path); |
| if (ret < 0) { |
| goto err_out; |
| } |
| |
| update_map_file: |
| fp = local_fopen(attr_path, "w"); |
| if (!fp) { |
| ret = -1; |
| goto err_out; |
| } |
| |
| if (credp->fc_uid != -1) { |
| uid = credp->fc_uid; |
| } |
| if (credp->fc_gid != -1) { |
| gid = credp->fc_gid; |
| } |
| if (credp->fc_mode != -1) { |
| mode = credp->fc_mode; |
| } |
| if (credp->fc_rdev != -1) { |
| rdev = credp->fc_rdev; |
| } |
| |
| |
| if (uid != -1) { |
| fprintf(fp, "virtfs.uid=%d\n", uid); |
| } |
| if (gid != -1) { |
| fprintf(fp, "virtfs.gid=%d\n", gid); |
| } |
| if (mode != -1) { |
| fprintf(fp, "virtfs.mode=%d\n", mode); |
| } |
| if (rdev != -1) { |
| fprintf(fp, "virtfs.rdev=%d\n", rdev); |
| } |
| fclose(fp); |
| |
| err_out: |
| return ret; |
| } |
| |
| 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) |
| { |
| char buffer[PATH_MAX]; |
| |
| if (lchown(rpath(fs_ctx, path, buffer), 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->export_flags & V9FS_SEC_MASK) != V9FS_SM_NONE) { |
| return -1; |
| } |
| } |
| |
| if (chmod(rpath(fs_ctx, path, buffer), credp->fc_mode & 07777) < 0) { |
| return -1; |
| } |
| return 0; |
| } |
| |
| static ssize_t local_readlink(FsContext *fs_ctx, V9fsPath *fs_path, |
| char *buf, size_t bufsz) |
| { |
| ssize_t tsize = -1; |
| char buffer[PATH_MAX]; |
| char *path = fs_path->data; |
| |
| if ((fs_ctx->export_flags & V9FS_SM_MAPPED) || |
| (fs_ctx->export_flags & V9FS_SM_MAPPED_FILE)) { |
| int fd; |
| fd = open(rpath(fs_ctx, path, buffer), O_RDONLY | O_NOFOLLOW); |
| 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->export_flags & V9FS_SM_PASSTHROUGH) || |
| (fs_ctx->export_flags & V9FS_SM_NONE)) { |
| tsize = readlink(rpath(fs_ctx, path, buffer), buf, bufsz); |
| } |
| return tsize; |
| } |
| |
| static int local_close(FsContext *ctx, V9fsFidOpenState *fs) |
| { |
| return close(fs->fd); |
| } |
| |
| static int local_closedir(FsContext *ctx, V9fsFidOpenState *fs) |
| { |
| return closedir(fs->dir); |
| } |
| |
| static int local_open(FsContext *ctx, V9fsPath *fs_path, |
| int flags, V9fsFidOpenState *fs) |
| { |
| char buffer[PATH_MAX]; |
| char *path = fs_path->data; |
| |
| fs->fd = open(rpath(ctx, path, buffer), flags | O_NOFOLLOW); |
| return fs->fd; |
| } |
| |
| static int local_opendir(FsContext *ctx, |
| V9fsPath *fs_path, V9fsFidOpenState *fs) |
| { |
| char buffer[PATH_MAX]; |
| char *path = fs_path->data; |
| |
| fs->dir = opendir(rpath(ctx, path, buffer)); |
| if (!fs->dir) { |
| return -1; |
| } |
| return 0; |
| } |
| |
| static void local_rewinddir(FsContext *ctx, V9fsFidOpenState *fs) |
| { |
| return rewinddir(fs->dir); |
| } |
| |
| static off_t local_telldir(FsContext *ctx, V9fsFidOpenState *fs) |
| { |
| return telldir(fs->dir); |
| } |
| |
| static int local_readdir_r(FsContext *ctx, V9fsFidOpenState *fs, |
| struct dirent *entry, |
| struct dirent **result) |
| { |
| int ret; |
| |
| again: |
| ret = readdir_r(fs->dir, entry, result); |
| if (ctx->export_flags & V9FS_SM_MAPPED_FILE) { |
| if (!ret && *result != NULL && |
| !strcmp(entry->d_name, VIRTFS_META_DIR)) { |
| /* skp the meta data directory */ |
| goto again; |
| } |
| } |
| return ret; |
| } |
| |
| static void local_seekdir(FsContext *ctx, V9fsFidOpenState *fs, off_t off) |
| { |
| return seekdir(fs->dir, off); |
| } |
| |
| static ssize_t local_preadv(FsContext *ctx, V9fsFidOpenState *fs, |
| const struct iovec *iov, |
| int iovcnt, off_t offset) |
| { |
| #ifdef CONFIG_PREADV |
| return preadv(fs->fd, iov, iovcnt, offset); |
| #else |
| int err = lseek(fs->fd, offset, SEEK_SET); |
| if (err == -1) { |
| return err; |
| } else { |
| return readv(fs->fd, iov, iovcnt); |
| } |
| #endif |
| } |
| |
| static ssize_t local_pwritev(FsContext *ctx, V9fsFidOpenState *fs, |
| const struct iovec *iov, |
| int iovcnt, off_t offset) |
| { |
| ssize_t ret |
| ; |
| #ifdef CONFIG_PREADV |
| ret = pwritev(fs->fd, iov, iovcnt, offset); |
| #else |
| int err = lseek(fs->fd, offset, SEEK_SET); |
| if (err == -1) { |
| return err; |
| } else { |
| ret = writev(fs->fd, iov, iovcnt); |
| } |
| #endif |
| #ifdef CONFIG_SYNC_FILE_RANGE |
| if (ret > 0 && ctx->export_flags & V9FS_IMMEDIATE_WRITEOUT) { |
| /* |
| * Initiate a writeback. This is not a data integrity sync. |
| * We want to ensure that we don't leave dirty pages in the cache |
| * after write when writeout=immediate is sepcified. |
| */ |
| sync_file_range(fs->fd, offset, ret, |
| SYNC_FILE_RANGE_WAIT_BEFORE | SYNC_FILE_RANGE_WRITE); |
| } |
| #endif |
| return ret; |
| } |
| |
| static int local_chmod(FsContext *fs_ctx, V9fsPath *fs_path, FsCred *credp) |
| { |
| char buffer[PATH_MAX]; |
| char *path = fs_path->data; |
| |
| if (fs_ctx->export_flags & V9FS_SM_MAPPED) { |
| return local_set_xattr(rpath(fs_ctx, path, buffer), credp); |
| } else if (fs_ctx->export_flags & V9FS_SM_MAPPED_FILE) { |
| return local_set_mapped_file_attr(fs_ctx, path, credp); |
| } else if ((fs_ctx->export_flags & V9FS_SM_PASSTHROUGH) || |
| (fs_ctx->export_flags & V9FS_SM_NONE)) { |
| return chmod(rpath(fs_ctx, path, buffer), credp->fc_mode); |
| } |
| return -1; |
| } |
| |
| static int local_mknod(FsContext *fs_ctx, V9fsPath *dir_path, |
| const char *name, FsCred *credp) |
| { |
| char *path; |
| int err = -1; |
| int serrno = 0; |
| V9fsString fullname; |
| char buffer[PATH_MAX]; |
| |
| v9fs_string_init(&fullname); |
| v9fs_string_sprintf(&fullname, "%s/%s", dir_path->data, name); |
| path = fullname.data; |
| |
| /* Determine the security model */ |
| if (fs_ctx->export_flags & V9FS_SM_MAPPED) { |
| err = mknod(rpath(fs_ctx, path, buffer), |
| SM_LOCAL_MODE_BITS|S_IFREG, 0); |
| if (err == -1) { |
| goto out; |
| } |
| err = local_set_xattr(rpath(fs_ctx, path, buffer), credp); |
| if (err == -1) { |
| serrno = errno; |
| goto err_end; |
| } |
| } else if (fs_ctx->export_flags & V9FS_SM_MAPPED_FILE) { |
| |
| err = mknod(rpath(fs_ctx, path, buffer), |
| SM_LOCAL_MODE_BITS|S_IFREG, 0); |
| if (err == -1) { |
| goto out; |
| } |
| err = local_set_mapped_file_attr(fs_ctx, path, credp); |
| if (err == -1) { |
| serrno = errno; |
| goto err_end; |
| } |
| } else if ((fs_ctx->export_flags & V9FS_SM_PASSTHROUGH) || |
| (fs_ctx->export_flags & V9FS_SM_NONE)) { |
| err = mknod(rpath(fs_ctx, path, buffer), credp->fc_mode, |
| credp->fc_rdev); |
| if (err == -1) { |
| goto out; |
| } |
| err = local_post_create_passthrough(fs_ctx, path, credp); |
| if (err == -1) { |
| serrno = errno; |
| goto err_end; |
| } |
| } |
| goto out; |
| |
| err_end: |
| remove(rpath(fs_ctx, path, buffer)); |
| errno = serrno; |
| out: |
| v9fs_string_free(&fullname); |
| return err; |
| } |
| |
| static int local_mkdir(FsContext *fs_ctx, V9fsPath *dir_path, |
| const char *name, FsCred *credp) |
| { |
| char *path; |
| int err = -1; |
| int serrno = 0; |
| V9fsString fullname; |
| char buffer[PATH_MAX]; |
| |
| v9fs_string_init(&fullname); |
| v9fs_string_sprintf(&fullname, "%s/%s", dir_path->data, name); |
| path = fullname.data; |
| |
| /* Determine the security model */ |
| if (fs_ctx->export_flags & V9FS_SM_MAPPED) { |
| err = mkdir(rpath(fs_ctx, path, buffer), SM_LOCAL_DIR_MODE_BITS); |
| if (err == -1) { |
| goto out; |
| } |
| credp->fc_mode = credp->fc_mode|S_IFDIR; |
| err = local_set_xattr(rpath(fs_ctx, path, buffer), credp); |
| if (err == -1) { |
| serrno = errno; |
| goto err_end; |
| } |
| } else if (fs_ctx->export_flags & V9FS_SM_MAPPED_FILE) { |
| err = mkdir(rpath(fs_ctx, path, buffer), SM_LOCAL_DIR_MODE_BITS); |
| if (err == -1) { |
| goto out; |
| } |
| credp->fc_mode = credp->fc_mode|S_IFDIR; |
| err = local_set_mapped_file_attr(fs_ctx, path, credp); |
| if (err == -1) { |
| serrno = errno; |
| goto err_end; |
| } |
| } else if ((fs_ctx->export_flags & V9FS_SM_PASSTHROUGH) || |
| (fs_ctx->export_flags & V9FS_SM_NONE)) { |
| err = mkdir(rpath(fs_ctx, path, buffer), credp->fc_mode); |
| if (err == -1) { |
| goto out; |
| } |
| err = local_post_create_passthrough(fs_ctx, path, credp); |
| if (err == -1) { |
| serrno = errno; |
| goto err_end; |
| } |
| } |
| goto out; |
| |
| err_end: |
| remove(rpath(fs_ctx, path, buffer)); |
| errno = serrno; |
| out: |
| v9fs_string_free(&fullname); |
| return err; |
| } |
| |
| static int local_fstat(FsContext *fs_ctx, int fid_type, |
| V9fsFidOpenState *fs, struct stat *stbuf) |
| { |
| int err, fd; |
| |
| if (fid_type == P9_FID_DIR) { |
| fd = dirfd(fs->dir); |
| } else { |
| fd = fs->fd; |
| } |
| |
| err = fstat(fd, stbuf); |
| if (err) { |
| return err; |
| } |
| if (fs_ctx->export_flags & V9FS_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; |
| } |
| } else if (fs_ctx->export_flags & V9FS_SM_MAPPED_FILE) { |
| errno = EOPNOTSUPP; |
| return -1; |
| } |
| return err; |
| } |
| |
| static int local_open2(FsContext *fs_ctx, V9fsPath *dir_path, const char *name, |
| int flags, FsCred *credp, V9fsFidOpenState *fs) |
| { |
| char *path; |
| int fd = -1; |
| int err = -1; |
| int serrno = 0; |
| V9fsString fullname; |
| char buffer[PATH_MAX]; |
| |
| /* |
| * Mark all the open to not follow symlinks |
| */ |
| flags |= O_NOFOLLOW; |
| |
| v9fs_string_init(&fullname); |
| v9fs_string_sprintf(&fullname, "%s/%s", dir_path->data, name); |
| path = fullname.data; |
| |
| /* Determine the security model */ |
| if (fs_ctx->export_flags & V9FS_SM_MAPPED) { |
| fd = open(rpath(fs_ctx, path, buffer), flags, SM_LOCAL_MODE_BITS); |
| if (fd == -1) { |
| err = fd; |
| goto out; |
| } |
| credp->fc_mode = credp->fc_mode|S_IFREG; |
| /* Set cleint credentials in xattr */ |
| err = local_set_xattr(rpath(fs_ctx, path, buffer), credp); |
| if (err == -1) { |
| serrno = errno; |
| goto err_end; |
| } |
| } else if (fs_ctx->export_flags & V9FS_SM_MAPPED_FILE) { |
| fd = open(rpath(fs_ctx, path, buffer), flags, SM_LOCAL_MODE_BITS); |
| if (fd == -1) { |
| err = fd; |
| goto out; |
| } |
| credp->fc_mode = credp->fc_mode|S_IFREG; |
| /* Set client credentials in .virtfs_metadata directory files */ |
| err = local_set_mapped_file_attr(fs_ctx, path, credp); |
| if (err == -1) { |
| serrno = errno; |
| goto err_end; |
| } |
| } else if ((fs_ctx->export_flags & V9FS_SM_PASSTHROUGH) || |
| (fs_ctx->export_flags & V9FS_SM_NONE)) { |
| fd = open(rpath(fs_ctx, path, buffer), flags, credp->fc_mode); |
| if (fd == -1) { |
| err = fd; |
| goto out; |
| } |
| err = local_post_create_passthrough(fs_ctx, path, credp); |
| if (err == -1) { |
| serrno = errno; |
| goto err_end; |
| } |
| } |
| err = fd; |
| fs->fd = fd; |
| goto out; |
| |
| err_end: |
| close(fd); |
| remove(rpath(fs_ctx, path, buffer)); |
| errno = serrno; |
| out: |
| v9fs_string_free(&fullname); |
| return err; |
| } |
| |
| |
| static int local_symlink(FsContext *fs_ctx, const char *oldpath, |
| V9fsPath *dir_path, const char *name, FsCred *credp) |
| { |
| int err = -1; |
| int serrno = 0; |
| char *newpath; |
| V9fsString fullname; |
| char buffer[PATH_MAX]; |
| |
| v9fs_string_init(&fullname); |
| v9fs_string_sprintf(&fullname, "%s/%s", dir_path->data, name); |
| newpath = fullname.data; |
| |
| /* Determine the security model */ |
| if (fs_ctx->export_flags & V9FS_SM_MAPPED) { |
| int fd; |
| ssize_t oldpath_size, write_size; |
| fd = open(rpath(fs_ctx, newpath, buffer), |
| O_CREAT|O_EXCL|O_RDWR|O_NOFOLLOW, |
| SM_LOCAL_MODE_BITS); |
| if (fd == -1) { |
| err = fd; |
| goto out; |
| } |
| /* 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, buffer), credp); |
| if (err == -1) { |
| serrno = errno; |
| goto err_end; |
| } |
| } else if (fs_ctx->export_flags & V9FS_SM_MAPPED_FILE) { |
| int fd; |
| ssize_t oldpath_size, write_size; |
| fd = open(rpath(fs_ctx, newpath, buffer), |
| O_CREAT|O_EXCL|O_RDWR|O_NOFOLLOW, |
| SM_LOCAL_MODE_BITS); |
| if (fd == -1) { |
| err = fd; |
| goto out; |
| } |
| /* 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_mapped_file_attr(fs_ctx, newpath, credp); |
| if (err == -1) { |
| serrno = errno; |
| goto err_end; |
| } |
| } else if ((fs_ctx->export_flags & V9FS_SM_PASSTHROUGH) || |
| (fs_ctx->export_flags & V9FS_SM_NONE)) { |
| err = symlink(oldpath, rpath(fs_ctx, newpath, buffer)); |
| if (err) { |
| goto out; |
| } |
| err = lchown(rpath(fs_ctx, newpath, buffer), 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->export_flags & V9FS_SEC_MASK) != V9FS_SM_NONE) { |
| serrno = errno; |
| goto err_end; |
| } else |
| err = 0; |
| } |
| } |
| goto out; |
| |
| err_end: |
| remove(rpath(fs_ctx, newpath, buffer)); |
| errno = serrno; |
| out: |
| v9fs_string_free(&fullname); |
| return err; |
| } |
| |
| static int local_link(FsContext *ctx, V9fsPath *oldpath, |
| V9fsPath *dirpath, const char *name) |
| { |
| int ret; |
| V9fsString newpath; |
| char buffer[PATH_MAX], buffer1[PATH_MAX]; |
| |
| v9fs_string_init(&newpath); |
| v9fs_string_sprintf(&newpath, "%s/%s", dirpath->data, name); |
| |
| ret = link(rpath(ctx, oldpath->data, buffer), |
| rpath(ctx, newpath.data, buffer1)); |
| |
| /* now link the virtfs_metadata files */ |
| if (!ret && (ctx->export_flags & V9FS_SM_MAPPED_FILE)) { |
| /* Link the .virtfs_metadata files. Create the metada directory */ |
| ret = local_create_mapped_attr_dir(ctx, newpath.data); |
| if (ret < 0) { |
| goto err_out; |
| } |
| ret = link(local_mapped_attr_path(ctx, oldpath->data, buffer), |
| local_mapped_attr_path(ctx, newpath.data, buffer1)); |
| if (ret < 0 && errno != ENOENT) { |
| goto err_out; |
| } |
| } |
| err_out: |
| v9fs_string_free(&newpath); |
| return ret; |
| } |
| |
| static int local_truncate(FsContext *ctx, V9fsPath *fs_path, off_t size) |
| { |
| char buffer[PATH_MAX]; |
| char *path = fs_path->data; |
| |
| return truncate(rpath(ctx, path, buffer), size); |
| } |
| |
| static int local_rename(FsContext *ctx, const char *oldpath, |
| const char *newpath) |
| { |
| int err; |
| char buffer[PATH_MAX], buffer1[PATH_MAX]; |
| |
| if (ctx->export_flags & V9FS_SM_MAPPED_FILE) { |
| err = local_create_mapped_attr_dir(ctx, newpath); |
| if (err < 0) { |
| return err; |
| } |
| /* rename the .virtfs_metadata files */ |
| err = rename(local_mapped_attr_path(ctx, oldpath, buffer), |
| local_mapped_attr_path(ctx, newpath, buffer1)); |
| if (err < 0 && errno != ENOENT) { |
| return err; |
| } |
| } |
| return rename(rpath(ctx, oldpath, buffer), rpath(ctx, newpath, buffer1)); |
| } |
| |
| static int local_chown(FsContext *fs_ctx, V9fsPath *fs_path, FsCred *credp) |
| { |
| char buffer[PATH_MAX]; |
| char *path = fs_path->data; |
| |
| if ((credp->fc_uid == -1 && credp->fc_gid == -1) || |
| (fs_ctx->export_flags & V9FS_SM_PASSTHROUGH) || |
| (fs_ctx->export_flags & V9FS_SM_NONE)) { |
| return lchown(rpath(fs_ctx, path, buffer), |
| credp->fc_uid, credp->fc_gid); |
| } else if (fs_ctx->export_flags & V9FS_SM_MAPPED) { |
| return local_set_xattr(rpath(fs_ctx, path, buffer), credp); |
| } else if (fs_ctx->export_flags & V9FS_SM_MAPPED_FILE) { |
| return local_set_mapped_file_attr(fs_ctx, path, credp); |
| } |
| return -1; |
| } |
| |
| static int local_utimensat(FsContext *s, V9fsPath *fs_path, |
| const struct timespec *buf) |
| { |
| char buffer[PATH_MAX]; |
| char *path = fs_path->data; |
| |
| return qemu_utimens(rpath(s, path, buffer), buf); |
| } |
| |
| static int local_remove(FsContext *ctx, const char *path) |
| { |
| int err; |
| struct stat stbuf; |
| char buffer[PATH_MAX]; |
| |
| if (ctx->export_flags & V9FS_SM_MAPPED_FILE) { |
| err = lstat(rpath(ctx, path, buffer), &stbuf); |
| if (err) { |
| goto err_out; |
| } |
| /* |
| * If directory remove .virtfs_metadata contained in the |
| * directory |
| */ |
| if (S_ISDIR(stbuf.st_mode)) { |
| sprintf(buffer, "%s/%s/%s", ctx->fs_root, path, VIRTFS_META_DIR); |
| err = remove(buffer); |
| if (err < 0 && errno != ENOENT) { |
| /* |
| * We didn't had the .virtfs_metadata file. May be file created |
| * in non-mapped mode ?. Ignore ENOENT. |
| */ |
| goto err_out; |
| } |
| } |
| /* |
| * Now remove the name from parent directory |
| * .virtfs_metadata directory |
| */ |
| err = remove(local_mapped_attr_path(ctx, path, buffer)); |
| if (err < 0 && errno != ENOENT) { |
| /* |
| * We didn't had the .virtfs_metadata file. May be file created |
| * in non-mapped mode ?. Ignore ENOENT. |
| */ |
| goto err_out; |
| } |
| } |
| return remove(rpath(ctx, path, buffer)); |
| err_out: |
| return err; |
| } |
| |
| static int local_fsync(FsContext *ctx, int fid_type, |
| V9fsFidOpenState *fs, int datasync) |
| { |
| int fd; |
| |
| if (fid_type == P9_FID_DIR) { |
| fd = dirfd(fs->dir); |
| } else { |
| fd = fs->fd; |
| } |
| |
| if (datasync) { |
| return qemu_fdatasync(fd); |
| } else { |
| return fsync(fd); |
| } |
| } |
| |
| static int local_statfs(FsContext *s, V9fsPath *fs_path, struct statfs *stbuf) |
| { |
| char buffer[PATH_MAX]; |
| char *path = fs_path->data; |
| |
| return statfs(rpath(s, path, buffer), stbuf); |
| } |
| |
| static ssize_t local_lgetxattr(FsContext *ctx, V9fsPath *fs_path, |
| const char *name, void *value, size_t size) |
| { |
| char *path = fs_path->data; |
| |
| return v9fs_get_xattr(ctx, path, name, value, size); |
| } |
| |
| static ssize_t local_llistxattr(FsContext *ctx, V9fsPath *fs_path, |
| void *value, size_t size) |
| { |
| char *path = fs_path->data; |
| |
| return v9fs_list_xattr(ctx, path, value, size); |
| } |
| |
| static int local_lsetxattr(FsContext *ctx, V9fsPath *fs_path, const char *name, |
| void *value, size_t size, int flags) |
| { |
| char *path = fs_path->data; |
| |
| return v9fs_set_xattr(ctx, path, name, value, size, flags); |
| } |
| |
| static int local_lremovexattr(FsContext *ctx, V9fsPath *fs_path, |
| const char *name) |
| { |
| char *path = fs_path->data; |
| |
| return v9fs_remove_xattr(ctx, path, name); |
| } |
| |
| static int local_name_to_path(FsContext *ctx, V9fsPath *dir_path, |
| const char *name, V9fsPath *target) |
| { |
| if (dir_path) { |
| v9fs_string_sprintf((V9fsString *)target, "%s/%s", |
| dir_path->data, name); |
| } else { |
| v9fs_string_sprintf((V9fsString *)target, "%s", name); |
| } |
| /* Bump the size for including terminating NULL */ |
| target->size++; |
| return 0; |
| } |
| |
| static int local_renameat(FsContext *ctx, V9fsPath *olddir, |
| const char *old_name, V9fsPath *newdir, |
| const char *new_name) |
| { |
| int ret; |
| V9fsString old_full_name, new_full_name; |
| |
| v9fs_string_init(&old_full_name); |
| v9fs_string_init(&new_full_name); |
| |
| v9fs_string_sprintf(&old_full_name, "%s/%s", olddir->data, old_name); |
| v9fs_string_sprintf(&new_full_name, "%s/%s", newdir->data, new_name); |
| |
| ret = local_rename(ctx, old_full_name.data, new_full_name.data); |
| v9fs_string_free(&old_full_name); |
| v9fs_string_free(&new_full_name); |
| return ret; |
| } |
| |
| static int local_unlinkat(FsContext *ctx, V9fsPath *dir, |
| const char *name, int flags) |
| { |
| int ret; |
| V9fsString fullname; |
| char buffer[PATH_MAX]; |
| |
| v9fs_string_init(&fullname); |
| |
| v9fs_string_sprintf(&fullname, "%s/%s", dir->data, name); |
| if (ctx->export_flags & V9FS_SM_MAPPED_FILE) { |
| if (flags == AT_REMOVEDIR) { |
| /* |
| * If directory remove .virtfs_metadata contained in the |
| * directory |
| */ |
| sprintf(buffer, "%s/%s/%s", ctx->fs_root, |
| fullname.data, VIRTFS_META_DIR); |
| ret = remove(buffer); |
| if (ret < 0 && errno != ENOENT) { |
| /* |
| * We didn't had the .virtfs_metadata file. May be file created |
| * in non-mapped mode ?. Ignore ENOENT. |
| */ |
| goto err_out; |
| } |
| } |
| /* |
| * Now remove the name from parent directory |
| * .virtfs_metadata directory. |
| */ |
| ret = remove(local_mapped_attr_path(ctx, fullname.data, buffer)); |
| if (ret < 0 && errno != ENOENT) { |
| /* |
| * We didn't had the .virtfs_metadata file. May be file created |
| * in non-mapped mode ?. Ignore ENOENT. |
| */ |
| goto err_out; |
| } |
| } |
| /* Remove the name finally */ |
| ret = remove(rpath(ctx, fullname.data, buffer)); |
| v9fs_string_free(&fullname); |
| |
| err_out: |
| return ret; |
| } |
| |
| static int local_ioc_getversion(FsContext *ctx, V9fsPath *path, |
| mode_t st_mode, uint64_t *st_gen) |
| { |
| int err; |
| #ifdef FS_IOC_GETVERSION |
| V9fsFidOpenState fid_open; |
| |
| /* |
| * Do not try to open special files like device nodes, fifos etc |
| * We can get fd for regular files and directories only |
| */ |
| if (!S_ISREG(st_mode) && !S_ISDIR(st_mode)) { |
| return 0; |
| } |
| err = local_open(ctx, path, O_RDONLY, &fid_open); |
| if (err < 0) { |
| return err; |
| } |
| err = ioctl(fid_open.fd, FS_IOC_GETVERSION, st_gen); |
| local_close(ctx, &fid_open); |
| #else |
| err = -ENOTTY; |
| #endif |
| return err; |
| } |
| |
| static int local_init(FsContext *ctx) |
| { |
| int err = 0; |
| struct statfs stbuf; |
| |
| if (ctx->export_flags & V9FS_SM_PASSTHROUGH) { |
| ctx->xops = passthrough_xattr_ops; |
| } else if (ctx->export_flags & V9FS_SM_MAPPED) { |
| ctx->xops = mapped_xattr_ops; |
| } else if (ctx->export_flags & V9FS_SM_NONE) { |
| ctx->xops = none_xattr_ops; |
| } else if (ctx->export_flags & V9FS_SM_MAPPED_FILE) { |
| /* |
| * xattr operation for mapped-file and passthrough |
| * remain same. |
| */ |
| ctx->xops = passthrough_xattr_ops; |
| } |
| ctx->export_flags |= V9FS_PATHNAME_FSCONTEXT; |
| #ifdef FS_IOC_GETVERSION |
| /* |
| * use ioc_getversion only if the iocl is definied |
| */ |
| err = statfs(ctx->fs_root, &stbuf); |
| if (!err) { |
| switch (stbuf.f_type) { |
| case EXT2_SUPER_MAGIC: |
| case BTRFS_SUPER_MAGIC: |
| case REISERFS_SUPER_MAGIC: |
| case XFS_SUPER_MAGIC: |
| ctx->exops.get_st_gen = local_ioc_getversion; |
| break; |
| } |
| } |
| #endif |
| return err; |
| } |
| |
| static int local_parse_opts(QemuOpts *opts, struct FsDriverEntry *fse) |
| { |
| const char *sec_model = qemu_opt_get(opts, "security_model"); |
| const char *path = qemu_opt_get(opts, "path"); |
| |
| if (!sec_model) { |
| fprintf(stderr, "security model not specified, " |
| "local fs needs security model\nvalid options are:" |
| "\tsecurity_model=[passthrough|mapped|none]\n"); |
| return -1; |
| } |
| |
| if (!strcmp(sec_model, "passthrough")) { |
| fse->export_flags |= V9FS_SM_PASSTHROUGH; |
| } else if (!strcmp(sec_model, "mapped") || |
| !strcmp(sec_model, "mapped-xattr")) { |
| fse->export_flags |= V9FS_SM_MAPPED; |
| } else if (!strcmp(sec_model, "none")) { |
| fse->export_flags |= V9FS_SM_NONE; |
| } else if (!strcmp(sec_model, "mapped-file")) { |
| fse->export_flags |= V9FS_SM_MAPPED_FILE; |
| } else { |
| fprintf(stderr, "Invalid security model %s specified, valid options are" |
| "\n\t [passthrough|mapped-xattr|mapped-file|none]\n", |
| sec_model); |
| return -1; |
| } |
| |
| if (!path) { |
| fprintf(stderr, "fsdev: No path specified.\n"); |
| return -1; |
| } |
| fse->path = g_strdup(path); |
| |
| return 0; |
| } |
| |
| FileOperations local_ops = { |
| .parse_opts = local_parse_opts, |
| .init = local_init, |
| .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_r = local_readdir_r, |
| .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, |
| .name_to_path = local_name_to_path, |
| .renameat = local_renameat, |
| .unlinkat = local_unlinkat, |
| }; |
