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-rw-r--r--src/hw/9pfs/virtio-9p-local.c1280
1 files changed, 1280 insertions, 0 deletions
diff --git a/src/hw/9pfs/virtio-9p-local.c b/src/hw/9pfs/virtio-9p-local.c
new file mode 100644
index 0000000..f1f2e25
--- /dev/null
+++ b/src/hw/9pfs/virtio-9p-local.c
@@ -0,0 +1,1280 @@
+/*
+ * 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 "fsdev/qemu-fsdev.h" /* local_ops */
+#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 char *local_mapped_attr_path(FsContext *ctx, const char *path)
+{
+ int dirlen;
+ const char *name = strrchr(path, '/');
+ if (name) {
+ dirlen = name - path;
+ ++name;
+ } else {
+ name = path;
+ dirlen = 0;
+ }
+ return g_strdup_printf("%s/%.*s/%s/%s", ctx->fs_root,
+ dirlen, path, VIRTFS_META_DIR, name);
+}
+
+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;
+
+ attr_path = local_mapped_attr_path(ctx, path);
+ fp = local_fopen(attr_path, "r");
+ g_free(attr_path);
+ 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;
+ char *path = fs_path->data;
+
+ buffer = rpath(fs_ctx, path);
+ err = lstat(buffer, stbuf);
+ if (err) {
+ goto err_out;
+ }
+ 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(buffer, "user.virtfs.uid", &tmp_uid, sizeof(uid_t)) > 0) {
+ stbuf->st_uid = le32_to_cpu(tmp_uid);
+ }
+ if (getxattr(buffer, "user.virtfs.gid", &tmp_gid, sizeof(gid_t)) > 0) {
+ stbuf->st_gid = le32_to_cpu(tmp_gid);
+ }
+ if (getxattr(buffer, "user.virtfs.mode",
+ &tmp_mode, sizeof(mode_t)) > 0) {
+ stbuf->st_mode = le32_to_cpu(tmp_mode);
+ }
+ if (getxattr(buffer, "user.virtfs.rdev", &tmp_dev, sizeof(dev_t)) > 0) {
+ stbuf->st_rdev = le64_to_cpu(tmp_dev);
+ }
+ } else if (fs_ctx->export_flags & V9FS_SM_MAPPED_FILE) {
+ local_mapped_file_attr(fs_ctx, path, stbuf);
+ }
+
+err_out:
+ g_free(buffer);
+ return err;
+}
+
+static int local_create_mapped_attr_dir(FsContext *ctx, const char *path)
+{
+ int err;
+ char *attr_dir;
+ char *tmp_path = g_strdup(path);
+
+ attr_dir = g_strdup_printf("%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(attr_dir);
+ 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;
+ int uid = -1, gid = -1, mode = -1, rdev = -1;
+
+ attr_path = local_mapped_attr_path(ctx, path);
+ fp = local_fopen(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:
+ g_free(attr_path);
+ return ret;
+}
+
+static int local_set_xattr(const char *path, FsCred *credp)
+{
+ int err;
+
+ if (credp->fc_uid != -1) {
+ uint32_t tmp_uid = cpu_to_le32(credp->fc_uid);
+ err = setxattr(path, "user.virtfs.uid", &tmp_uid, sizeof(uid_t), 0);
+ if (err) {
+ return err;
+ }
+ }
+ if (credp->fc_gid != -1) {
+ uint32_t tmp_gid = cpu_to_le32(credp->fc_gid);
+ err = setxattr(path, "user.virtfs.gid", &tmp_gid, sizeof(gid_t), 0);
+ if (err) {
+ return err;
+ }
+ }
+ if (credp->fc_mode != -1) {
+ uint32_t tmp_mode = cpu_to_le32(credp->fc_mode);
+ err = setxattr(path, "user.virtfs.mode", &tmp_mode, sizeof(mode_t), 0);
+ if (err) {
+ return err;
+ }
+ }
+ if (credp->fc_rdev != -1) {
+ uint64_t tmp_rdev = cpu_to_le64(credp->fc_rdev);
+ err = setxattr(path, "user.virtfs.rdev", &tmp_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;
+
+ buffer = rpath(fs_ctx, path);
+ if (lchown(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) {
+ goto err;
+ }
+ }
+
+ if (chmod(buffer, credp->fc_mode & 07777) < 0) {
+ goto err;
+ }
+
+ g_free(buffer);
+ return 0;
+err:
+ g_free(buffer);
+ return -1;
+}
+
+static ssize_t local_readlink(FsContext *fs_ctx, V9fsPath *fs_path,
+ char *buf, size_t bufsz)
+{
+ ssize_t tsize = -1;
+ char *buffer;
+ char *path = fs_path->data;
+
+ if ((fs_ctx->export_flags & V9FS_SM_MAPPED) ||
+ (fs_ctx->export_flags & V9FS_SM_MAPPED_FILE)) {
+ int fd;
+ buffer = rpath(fs_ctx, path);
+ fd = open(buffer, O_RDONLY | O_NOFOLLOW);
+ g_free(buffer);
+ if (fd == -1) {
+ return -1;
+ }
+ do {
+ tsize = read(fd, (void *)buf, bufsz);
+ } while (tsize == -1 && errno == EINTR);
+ close(fd);
+ } else if ((fs_ctx->export_flags & V9FS_SM_PASSTHROUGH) ||
+ (fs_ctx->export_flags & V9FS_SM_NONE)) {
+ buffer = rpath(fs_ctx, path);
+ tsize = readlink(buffer, buf, bufsz);
+ g_free(buffer);
+ }
+ 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;
+ char *path = fs_path->data;
+
+ buffer = rpath(ctx, path);
+ fs->fd = open(buffer, flags | O_NOFOLLOW);
+ g_free(buffer);
+ return fs->fd;
+}
+
+static int local_opendir(FsContext *ctx,
+ V9fsPath *fs_path, V9fsFidOpenState *fs)
+{
+ char *buffer;
+ char *path = fs_path->data;
+
+ buffer = rpath(ctx, path);
+ fs->dir = opendir(buffer);
+ g_free(buffer);
+ if (!fs->dir) {
+ return -1;
+ }
+ return 0;
+}
+
+static void local_rewinddir(FsContext *ctx, V9fsFidOpenState *fs)
+{
+ 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) {
+ entry->d_type = DT_UNKNOWN;
+ } else 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;
+ }
+ entry->d_type = DT_UNKNOWN;
+ }
+ return ret;
+}
+
+static void local_seekdir(FsContext *ctx, V9fsFidOpenState *fs, off_t off)
+{
+ 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;
+ int ret = -1;
+ char *path = fs_path->data;
+
+ if (fs_ctx->export_flags & V9FS_SM_MAPPED) {
+ buffer = rpath(fs_ctx, path);
+ ret = local_set_xattr(buffer, credp);
+ g_free(buffer);
+ } 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)) {
+ buffer = rpath(fs_ctx, path);
+ ret = chmod(buffer, credp->fc_mode);
+ g_free(buffer);
+ }
+ return ret;
+}
+
+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 = NULL;
+
+ 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) {
+ buffer = rpath(fs_ctx, path);
+ err = mknod(buffer, SM_LOCAL_MODE_BITS|S_IFREG, 0);
+ if (err == -1) {
+ goto out;
+ }
+ err = local_set_xattr(buffer, credp);
+ if (err == -1) {
+ serrno = errno;
+ goto err_end;
+ }
+ } else if (fs_ctx->export_flags & V9FS_SM_MAPPED_FILE) {
+
+ buffer = rpath(fs_ctx, path);
+ err = mknod(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)) {
+ buffer = rpath(fs_ctx, path);
+ err = mknod(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(buffer);
+ errno = serrno;
+out:
+ g_free(buffer);
+ 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 = NULL;
+
+ 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) {
+ buffer = rpath(fs_ctx, path);
+ err = mkdir(buffer, SM_LOCAL_DIR_MODE_BITS);
+ if (err == -1) {
+ goto out;
+ }
+ credp->fc_mode = credp->fc_mode|S_IFDIR;
+ err = local_set_xattr(buffer, credp);
+ if (err == -1) {
+ serrno = errno;
+ goto err_end;
+ }
+ } else if (fs_ctx->export_flags & V9FS_SM_MAPPED_FILE) {
+ buffer = rpath(fs_ctx, path);
+ err = mkdir(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)) {
+ buffer = rpath(fs_ctx, path);
+ err = mkdir(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(buffer);
+ errno = serrno;
+out:
+ g_free(buffer);
+ 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 = le32_to_cpu(tmp_uid);
+ }
+ if (fgetxattr(fd, "user.virtfs.gid", &tmp_gid, sizeof(gid_t)) > 0) {
+ stbuf->st_gid = le32_to_cpu(tmp_gid);
+ }
+ if (fgetxattr(fd, "user.virtfs.mode", &tmp_mode, sizeof(mode_t)) > 0) {
+ stbuf->st_mode = le32_to_cpu(tmp_mode);
+ }
+ if (fgetxattr(fd, "user.virtfs.rdev", &tmp_dev, sizeof(dev_t)) > 0) {
+ stbuf->st_rdev = le64_to_cpu(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 = NULL;
+
+ /*
+ * 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) {
+ buffer = rpath(fs_ctx, path);
+ fd = open(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(buffer, credp);
+ if (err == -1) {
+ serrno = errno;
+ goto err_end;
+ }
+ } else if (fs_ctx->export_flags & V9FS_SM_MAPPED_FILE) {
+ buffer = rpath(fs_ctx, path);
+ fd = open(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)) {
+ buffer = rpath(fs_ctx, path);
+ fd = open(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(buffer);
+ errno = serrno;
+out:
+ g_free(buffer);
+ 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 = NULL;
+
+ 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;
+ buffer = rpath(fs_ctx, newpath);
+ fd = open(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(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;
+ buffer = rpath(fs_ctx, newpath);
+ fd = open(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)) {
+ buffer = rpath(fs_ctx, newpath);
+ err = symlink(oldpath, buffer);
+ if (err) {
+ goto out;
+ }
+ err = lchown(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(buffer);
+ errno = serrno;
+out:
+ g_free(buffer);
+ 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, *buffer1;
+
+ v9fs_string_init(&newpath);
+ v9fs_string_sprintf(&newpath, "%s/%s", dirpath->data, name);
+
+ buffer = rpath(ctx, oldpath->data);
+ buffer1 = rpath(ctx, newpath.data);
+ ret = link(buffer, buffer1);
+ g_free(buffer);
+ g_free(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;
+ }
+ buffer = local_mapped_attr_path(ctx, oldpath->data);
+ buffer1 = local_mapped_attr_path(ctx, newpath.data);
+ ret = link(buffer, buffer1);
+ g_free(buffer);
+ g_free(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;
+ int ret;
+ char *path = fs_path->data;
+
+ buffer = rpath(ctx, path);
+ ret = truncate(buffer, size);
+ g_free(buffer);
+ return ret;
+}
+
+static int local_rename(FsContext *ctx, const char *oldpath,
+ const char *newpath)
+{
+ int err;
+ char *buffer, *buffer1;
+
+ 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 */
+ buffer = local_mapped_attr_path(ctx, oldpath);
+ buffer1 = local_mapped_attr_path(ctx, newpath);
+ err = rename(buffer, buffer1);
+ g_free(buffer);
+ g_free(buffer1);
+ if (err < 0 && errno != ENOENT) {
+ return err;
+ }
+ }
+
+ buffer = rpath(ctx, oldpath);
+ buffer1 = rpath(ctx, newpath);
+ err = rename(buffer, buffer1);
+ g_free(buffer);
+ g_free(buffer1);
+ return err;
+}
+
+static int local_chown(FsContext *fs_ctx, V9fsPath *fs_path, FsCred *credp)
+{
+ char *buffer;
+ int ret = -1;
+ 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)) {
+ buffer = rpath(fs_ctx, path);
+ ret = lchown(buffer, credp->fc_uid, credp->fc_gid);
+ g_free(buffer);
+ } else if (fs_ctx->export_flags & V9FS_SM_MAPPED) {
+ buffer = rpath(fs_ctx, path);
+ ret = local_set_xattr(buffer, credp);
+ g_free(buffer);
+ } else if (fs_ctx->export_flags & V9FS_SM_MAPPED_FILE) {
+ return local_set_mapped_file_attr(fs_ctx, path, credp);
+ }
+ return ret;
+}
+
+static int local_utimensat(FsContext *s, V9fsPath *fs_path,
+ const struct timespec *buf)
+{
+ char *buffer;
+ int ret;
+ char *path = fs_path->data;
+
+ buffer = rpath(s, path);
+ ret = qemu_utimens(buffer, buf);
+ g_free(buffer);
+ return ret;
+}
+
+static int local_remove(FsContext *ctx, const char *path)
+{
+ int err;
+ struct stat stbuf;
+ char *buffer;
+
+ if (ctx->export_flags & V9FS_SM_MAPPED_FILE) {
+ buffer = rpath(ctx, path);
+ err = lstat(buffer, &stbuf);
+ g_free(buffer);
+ if (err) {
+ goto err_out;
+ }
+ /*
+ * If directory remove .virtfs_metadata contained in the
+ * directory
+ */
+ if (S_ISDIR(stbuf.st_mode)) {
+ buffer = g_strdup_printf("%s/%s/%s", ctx->fs_root,
+ path, VIRTFS_META_DIR);
+ err = remove(buffer);
+ g_free(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
+ */
+ buffer = local_mapped_attr_path(ctx, path);
+ err = remove(buffer);
+ g_free(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;
+ }
+ }
+
+ buffer = rpath(ctx, path);
+ err = remove(buffer);
+ g_free(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;
+ int ret;
+ char *path = fs_path->data;
+
+ buffer = rpath(s, path);
+ ret = statfs(buffer, stbuf);
+ g_free(buffer);
+ return ret;
+}
+
+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;
+
+ 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
+ */
+ buffer = g_strdup_printf("%s/%s/%s", ctx->fs_root,
+ fullname.data, VIRTFS_META_DIR);
+ ret = remove(buffer);
+ g_free(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.
+ */
+ buffer = local_mapped_attr_path(ctx, fullname.data);
+ ret = remove(buffer);
+ g_free(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 */
+ buffer = rpath(ctx, fullname.data);
+ ret = remove(buffer);
+ g_free(buffer);
+
+err_out:
+ v9fs_string_free(&fullname);
+ return ret;
+}
+
+static int local_ioc_getversion(FsContext *ctx, V9fsPath *path,
+ mode_t st_mode, uint64_t *st_gen)
+{
+#ifdef FS_IOC_GETVERSION
+ int err;
+ 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)) {
+ errno = ENOTTY;
+ return -1;
+ }
+ 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);
+ return err;
+#else
+ errno = ENOTTY;
+ return -1;
+#endif
+}
+
+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,
+};
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