Changed slightly the SFTP quote commands chmod, chown and chgrp to only

set the attribute that has changed instead of all possible ones. Hopefully,
this will solve the "Permission denied" problem that Nagarajan Sreenivasan
reported when setting some modes, but regardless, it saves a protocol
round trip in the chmod case.

1 files changed, 25 insertions, 16 deletions

diff --git a/lib/ssh.c b/lib/ssh.c
index 6f2392d6d..cb6e96c78 100644
--- a/lib/ssh.c
+++ b/lib/ssh.c
@@ -997,27 +997,34 @@ static CURLcode ssh_statemach_act(struct connectdata *conn)
     break;
 
   case SSH_SFTP_QUOTE_STAT:
-    rc = libssh2_sftp_stat(sshc->sftp_session, sshc->quote_path2,
-                           &sshc->quote_attrs);
-    if(rc == LIBSSH2_ERROR_EAGAIN) {
-      break;
-    }
-    else if(rc != 0) { /* get those attributes */
-      err = libssh2_sftp_last_error(sshc->sftp_session);
-      Curl_safefree(sshc->quote_path1);
-      sshc->quote_path1 = NULL;
-      Curl_safefree(sshc->quote_path2);
-      sshc->quote_path2 = NULL;
-      failf(data, "Attempt to get SFTP stats failed: %s",
-            sftp_libssh2_strerror(err));
-      state(conn, SSH_SFTP_CLOSE);
-      sshc->actualcode = CURLE_QUOTE_ERROR;
-      break;
+    if(!curl_strnequal(sshc->quote_item->data, "chmod", 5)) {
+      /* Since chown and chgrp only set owner OR group but libssh2 wants to
+       * set them both at once, we need to obtain the current ownership first.
+       * This takes an extra protocol round trip.
+       */
+      rc = libssh2_sftp_stat(sshc->sftp_session, sshc->quote_path2,
+			     &sshc->quote_attrs);
+      if(rc == LIBSSH2_ERROR_EAGAIN) {
+	break;
+      }
+      else if(rc != 0) { /* get those attributes */
+	err = libssh2_sftp_last_error(sshc->sftp_session);
+	Curl_safefree(sshc->quote_path1);
+	sshc->quote_path1 = NULL;
+	Curl_safefree(sshc->quote_path2);
+	sshc->quote_path2 = NULL;
+	failf(data, "Attempt to get SFTP stats failed: %s",
+	      sftp_libssh2_strerror(err));
+	state(conn, SSH_SFTP_CLOSE);
+	sshc->actualcode = CURLE_QUOTE_ERROR;
+	break;
+      }
     }
 
     /* Now set the new attributes... */
     if(curl_strnequal(sshc->quote_item->data, "chgrp", 5)) {
       sshc->quote_attrs.gid = strtol(sshc->quote_path1, NULL, 10);
+      sshc->quote_attrs.flags = LIBSSH2_SFTP_ATTR_UIDGID;
       if(sshc->quote_attrs.gid == 0 && !ISDIGIT(sshc->quote_path1[0])) {
         Curl_safefree(sshc->quote_path1);
         sshc->quote_path1 = NULL;
@@ -1031,6 +1038,7 @@ static CURLcode ssh_statemach_act(struct connectdata *conn)
     }
     else if(curl_strnequal(sshc->quote_item->data, "chmod", 5)) {
       sshc->quote_attrs.permissions = strtol(sshc->quote_path1, NULL, 8);
+      sshc->quote_attrs.flags = LIBSSH2_SFTP_ATTR_PERMISSIONS;
       /* permissions are octal */
       if(sshc->quote_attrs.permissions == 0 &&
          !ISDIGIT(sshc->quote_path1[0])) {
@@ -1046,6 +1054,7 @@ static CURLcode ssh_statemach_act(struct connectdata *conn)
     }
     else if(curl_strnequal(sshc->quote_item->data, "chown", 5)) {
       sshc->quote_attrs.uid = strtol(sshc->quote_path1, NULL, 10);
+      sshc->quote_attrs.flags = LIBSSH2_SFTP_ATTR_UIDGID;
       if(sshc->quote_attrs.uid == 0 && !ISDIGIT(sshc->quote_path1[0])) {
         Curl_safefree(sshc->quote_path1);
         sshc->quote_path1 = NULL;