symlink: rename and link handle ERROR_REPARSE

when rename or link call nfs41_lookup() for the destination directory, they need to be able to handle ERROR_REPARSE and find the real dest dir

open now does the same thing when it sees ERROR_REPARSE; previously, it was only replacing the first symlink in the path, and could require multiple reparses on a path

modified nfs41_symlink_target() to support the case where the source and destination paths are the same (used by rename/link)

Signed-off-by: Casey Bodley <cbodley@citi.umich.edu>

daemon/open.c

@@ -238,12 +238,20 @@ int handle_open(nfs41_upcall *upcall)
 
     if (status == ERROR_REPARSE) {
         /* one of the parent components was a symlink */
+        do {
+            /* replace the path with the symlink target's */
+            status = nfs41_symlink_target(state->session,
+                &state->parent, &state->path);
+
+            /* redo the lookup until it doesn't return REPARSE */
+            status = nfs41_lookup(args->root, state->session,
+                &state->path, &state->parent, NULL, NULL, &state->session);
+        } while (status == ERROR_REPARSE);
+
+        abs_path_copy(&args->symlink, &state->path);
+        status = NO_ERROR;
         upcall->last_error = ERROR_REPARSE;
         args->symlink_embedded = TRUE;
-
-        /* replace the path with the symlink target */
-        status = nfs41_symlink_target(state->session,
-            &state->parent, &args->symlink);
         goto out_free_state;
     }
 

daemon/setattr.c

@@ -199,6 +199,7 @@ static void open_state_rename(
 static int handle_nfs41_rename(setattr_upcall_args *args)
 {
     nfs41_open_state *state = args->state;
+    nfs41_session *dst_session;
     PFILE_RENAME_INFO rename = (PFILE_RENAME_INFO)args->buf;
     nfs41_abs_path dst_path;
     nfs41_path_fh dst_dir;
@@ -248,7 +249,16 @@ static int handle_nfs41_rename(setattr_upcall_args *args)
 
     /* the destination path is absolute, so start from the root session */
     status = nfs41_lookup(args->root, nfs41_root_session(args->root),
-        &dst_path, &dst_dir, NULL, NULL, NULL);
+        &dst_path, &dst_dir, NULL, NULL, &dst_session);
+
+    while (status == ERROR_REPARSE) {
+        /* replace the path with the symlink target's */
+        status = nfs41_symlink_target(dst_session, &dst_dir, &dst_path);
+
+        /* redo the lookup until it doesn't return REPARSE */
+        status = nfs41_lookup(args->root, dst_session,
+            &dst_path, &dst_dir, NULL, NULL, &dst_session);
+    }
 
     /* get the components after lookup in case a referral changed its path */
     last_component(dst_path.path, dst_path.path + dst_path.len, &dst_name);
@@ -322,6 +332,7 @@ int handle_nfs41_link(setattr_upcall_args *args)
 {
     nfs41_open_state *state = args->state;
     PFILE_LINK_INFORMATION link = (PFILE_LINK_INFORMATION)args->buf;
+    nfs41_session *dst_session;
     nfs41_abs_path dst_path;
     nfs41_path_fh dst_dir;
     nfs41_component dst_name;
@@ -342,7 +353,16 @@ int handle_nfs41_link(setattr_upcall_args *args)
 
     /* the destination path is absolute, so start from the root session */
     status = nfs41_lookup(args->root, nfs41_root_session(args->root),
-        &dst_path, &dst_dir, NULL, NULL, NULL);
+        &dst_path, &dst_dir, NULL, NULL, &dst_session);
+
+    while (status == ERROR_REPARSE) {
+        /* replace the path with the symlink target's */
+        status = nfs41_symlink_target(dst_session, &dst_dir, &dst_path);
+
+        /* redo the lookup until it doesn't return REPARSE */
+        status = nfs41_lookup(args->root, dst_session,
+            &dst_path, &dst_dir, NULL, NULL, &dst_session);
+    }
 
     /* get the components after lookup in case a referral changed its path */
     last_component(dst_path.path, dst_path.path + dst_path.len, &dst_name);

daemon/symlink.c

@@ -113,29 +113,31 @@ int nfs41_symlink_target(
 
     dprintf(2, "--> nfs41_symlink_target('%s', '%s')\n", path->path, link);
 
+    /* append any components after the symlink */
+    if (FAILED(StringCchCatA(link, NFS41_MAX_PATH_LEN,
+        file->name.name + file->name.len))) {
+        status = ERROR_BUFFER_OVERFLOW;
+        goto out;
+    }
+    link_len = (uint32_t)strlen(link);
+
     /* overwrite the last component of the path; get the starting offset */
     path_offset = file->name.name - path->path;
 
     /* copy the path and update it with the results from link */
-    target->len = path->len;
+    if (target != path) {
-    if (FAILED(StringCchCopyNA(target->path, NFS41_MAX_PATH_LEN,
+        target->len = path->len;
-        path->path, path->len))) {
+        if (FAILED(StringCchCopyNA(target->path, NFS41_MAX_PATH_LEN,
-        status = ERROR_BUFFER_OVERFLOW;
+            path->path, path->len))) {
-        goto out;
+            status = ERROR_BUFFER_OVERFLOW;
+            goto out;
+        }
     }
     status = abs_path_link(target, target->path + path_offset, link, link_len);
     if (status) {
         eprintf("abs_path_link() failed with %d\n", status);
         goto out;
     }
-
-    /* append any components after the symlink */
-    if (FAILED(StringCchCopyA(target->path + target->len,
-        NFS41_MAX_PATH_LEN - target->len, file->name.name + file->name.len))) {
-        status = ERROR_BUFFER_OVERFLOW;
-        goto out;
-    }
-    target->len = (unsigned short)strlen(target->path);
 out:
     dprintf(2, "<-- nfs41_symlink_target('%s') returning %d\n",
         target->path, status);