[evolution-data-server] I#172 - [IMAPx] Ignore truncated COPYUID server response

[Milan Crha <mcrha src gnome org>]

commit 1932c27efaf7ce2bee6f1f244cefb33ab839b933
Author: Milan Crha <mcrha redhat com>
Date:   Mon Aug 31 11:46:01 2020 +0200

    I#172 -  [IMAPx] Ignore truncated COPYUID server response
    
    Closes https://gitlab.gnome.org/GNOME/evolution-data-server/-/issues/172

 src/camel/providers/imapx/camel-imapx-server.c | 34 +++++++++++++++++++++++++-
 1 file changed, 33 insertions(+), 1 deletion(-)
---
diff --git a/src/camel/providers/imapx/camel-imapx-server.c b/src/camel/providers/imapx/camel-imapx-server.c
index 816c6e66e2..b04012da63 100644
--- a/src/camel/providers/imapx/camel-imapx-server.c
+++ b/src/camel/providers/imapx/camel-imapx-server.c
@@ -930,6 +930,9 @@ imapx_untagged_vanished (CamelIMAPXServer *is,
        geud.n_uids = 0;
 
        if (!imapx_parse_uids_with_callback (CAMEL_IMAPX_INPUT_STREAM (input_stream), 
imapx_gather_existing_uids_cb, &geud, cancellable, error)) {
+               if (error && g_error_matches (*error, CAMEL_IMAPX_ERROR, CAMEL_IMAPX_ERROR_IGNORE))
+                       (*error)->code = CAMEL_IMAPX_ERROR_SERVER_RESPONSE_MALFORMED;
+
                g_object_unref (folder);
                g_object_unref (mailbox);
                return FALSE;
@@ -2626,6 +2629,32 @@ imapx_step (CamelIMAPXServer *is,
                                FALSE, cancellable, error);
                        break;
                default:
+                       if (tok == '[') {
+                               CamelIMAPXCommand *cmd;
+                               gboolean handled = FALSE;
+
+                               cmd = camel_imapx_server_ref_current_command (is);
+
+                               if (cmd && (cmd->job_kind == CAMEL_IMAPX_JOB_COPY_MESSAGE || cmd->job_kind == 
CAMEL_IMAPX_JOB_MOVE_MESSAGE) &&
+                                   camel_imapx_input_stream_atom (CAMEL_IMAPX_INPUT_STREAM (input_stream), 
&token, &len, cancellable, NULL) &&
+                                   imapx_tokenise ((const gchar *) token, len) == IMAPX_COPYUID) {
+                                       /* Ignore malformed COPYUID response (expects "* OK [COPYUID ....]" 
or "A123 OK [COPYUID ...]", but received "[COPYUID ....]") */
+                                       camel_imapx_input_stream_skip (CAMEL_IMAPX_INPUT_STREAM 
(input_stream), cancellable, NULL);
+
+                                       g_set_error_literal (
+                                               error, CAMEL_IMAPX_ERROR, CAMEL_IMAPX_ERROR_IGNORE,
+                                               "malformed COPYUID server response");
+
+                                       handled = TRUE;
+                               }
+
+                               if (cmd)
+                                       camel_imapx_command_unref (cmd);
+
+                               if (handled)
+                                       break;
+                       }
+
                        g_set_error (
                                error, CAMEL_IMAPX_ERROR, CAMEL_IMAPX_ERROR_SERVER_RESPONSE_MALFORMED,
                                "unexpected server response:");
@@ -4184,7 +4213,10 @@ camel_imapx_server_process_command_sync (CamelIMAPXServer *is,
                        "%s", ic->status->text);
        }
 
-       if (local_error) {
+       if (g_error_matches (local_error, CAMEL_IMAPX_ERROR, CAMEL_IMAPX_ERROR_IGNORE)) {
+               g_clear_error (&local_error);
+               success = TRUE;
+       } else if (local_error) {
                /* Sadly, G_IO_ERROR_FAILED is also used for 'Connection reset by peer' error;
                   since GLib 2.44 is used G_IO_ERROR_CONNECTION_CLOSED, which is the same as 
G_IO_ERROR_BROKEN_PIPE */
                if (g_error_matches (local_error, G_IO_ERROR, G_IO_ERROR_FAILED) ||