s3: VFS: gluster: Add vfs_gluster_read_dfs_pathat().

Not yet used.

BUG: https://bugzilla.samba.org/show_bug.cgi?id=14282

Signed-off-by: Jeremy Allison <jra@samba.org>
Reviewed-by: Ralph Boehme <slow@samba.org>
(cherry picked from commit 018af49b93f8e9a2cbc0d40cc68b8202e5c95c9a)

diff --git a/source3/modules/vfs_glusterfs.c b/source3/modules/vfs_glusterfs.c
index 059aeb42ab58afb661b4c2e7b890fde56fc272b7..d4b68fba37671892f6634eb283f314568410b746 100644 (file)
--- a/source3/modules/vfs_glusterfs.c
+++ b/source3/modules/vfs_glusterfs.c
@@ -1933,6 +1933,103 @@ static NTSTATUS vfs_gluster_create_dfs_pathat(struct vfs_handle_struct *handle,
        return status;
 }
 
+/*
+ * Read and return the contents of a DFS redirect given a
+ * pathname. A caller can pass in NULL for ppreflist and
+ * preferral_count but still determine if this was a
+ * DFS redirect point by getting NT_STATUS_OK back
+ * without incurring the overhead of reading and parsing
+ * the referral contents.
+ */
+
+static NTSTATUS vfs_gluster_read_dfs_pathat(struct vfs_handle_struct *handle,
+                               TALLOC_CTX *mem_ctx,
+                               struct files_struct *dirfsp,
+                               const struct smb_filename *smb_fname,
+                               struct referral **ppreflist,
+                               size_t *preferral_count)
+{
+       NTSTATUS status = NT_STATUS_NO_MEMORY;
+       size_t bufsize;
+       char *link_target = NULL;
+       int referral_len;
+       bool ok;
+#if defined(HAVE_BROKEN_READLINK)
+       char link_target_buf[PATH_MAX];
+#else
+       char link_target_buf[7];
+#endif
+
+       SMB_ASSERT(dirfsp == dirfsp->conn->cwd_fsp);
+
+       if (ppreflist == NULL && preferral_count == NULL) {
+               /*
+                * We're only checking if this is a DFS
+                * redirect. We don't need to return data.
+                */
+               bufsize = sizeof(link_target_buf);
+               link_target = link_target_buf;
+       } else {
+               bufsize = PATH_MAX;
+               link_target = talloc_array(mem_ctx, char, bufsize);
+               if (!link_target) {
+                       goto err;
+               }
+       }
+
+       referral_len = glfs_readlink(handle->data,
+                               smb_fname->base_name,
+                               link_target,
+                               bufsize - 1);
+       if (referral_len < 0) {
+               if (errno == EINVAL) {
+                       DBG_INFO("%s is not a link.\n", smb_fname->base_name);
+                       status = NT_STATUS_OBJECT_TYPE_MISMATCH;
+               } else {
+                       status = map_nt_error_from_unix(errno);
+                       DBG_ERR("Error reading "
+                               "msdfs link %s: %s\n",
+                               smb_fname->base_name,
+                               strerror(errno));
+               }
+               goto err;
+       }
+       link_target[referral_len] = '\0';
+
+       DBG_INFO("%s -> %s\n",
+                       smb_fname->base_name,
+                       link_target);
+
+       if (!strnequal(link_target, "msdfs:", 6)) {
+               status = NT_STATUS_OBJECT_TYPE_MISMATCH;
+               goto err;
+       }
+
+       if (ppreflist == NULL && preferral_count == NULL) {
+               /* Early return for checking if this is a DFS link. */
+               return NT_STATUS_OK;
+       }
+
+       ok = parse_msdfs_symlink(mem_ctx,
+                       lp_msdfs_shuffle_referrals(SNUM(handle->conn)),
+                       link_target,
+                       ppreflist,
+                       preferral_count);
+
+       if (ok) {
+               status = NT_STATUS_OK;
+       } else {
+               status = NT_STATUS_NO_MEMORY;
+       }
+
+  err:
+
+       if (link_target != link_target_buf) {
+               TALLOC_FREE(link_target);
+       }
+       return status;
+}
+
 static struct vfs_fn_pointers glusterfs_fns = {
 
        /* Disk Operations */
@@ -2007,6 +2104,7 @@ static struct vfs_fn_pointers glusterfs_fns = {
        .get_real_filename_fn = vfs_gluster_get_real_filename,
        .connectpath_fn = vfs_gluster_connectpath,
        .create_dfs_pathat_fn = vfs_gluster_create_dfs_pathat,
+       .read_dfs_pathat_fn = vfs_gluster_read_dfs_pathat,
 
        .brl_lock_windows_fn = NULL,
        .brl_unlock_windows_fn = NULL,