[Fix] Try to fix double signing in the milter

Issue: #2810

diff --git a/src/libserver/protocol.c b/src/libserver/protocol.c
index 23690f45a9eac74c99283c518539e4a42414338c..34eaabe89376198894163a798d2ed1f75a29acd1 100644 (file)
--- a/src/libserver/protocol.c
+++ b/src/libserver/protocol.c
@@ -1233,38 +1233,56 @@ rspamd_protocol_write_ucl (struct rspamd_task *task,
                dkim_sigs = rspamd_mempool_get_variable (task->task_pool,
                                RSPAMD_MEMPOOL_DKIM_SIGNATURE);
 
-               for (; dkim_sigs != NULL; dkim_sigs = dkim_sigs->next) {
-                       GString *folded_header;
-                       dkim_sig = (GString *) dkim_sigs->data;
 
-                       if (task->flags & RSPAMD_TASK_FLAG_MILTER) {
-                               folded_header = rspamd_header_value_fold ("DKIM-Signature",
-                                               dkim_sig->str, 80, RSPAMD_TASK_NEWLINES_LF, NULL);
+               if (dkim_sigs) {
+                       if (dkim_sigs->next) {
+                               /* Multiple DKIM signatures */
+                               ucl_object_t *ar = ucl_object_typed_new (UCL_ARRAY);
+
+                               for (; dkim_sigs != NULL; dkim_sigs = dkim_sigs->next) {
+                                       GString *folded_header;
+                                       dkim_sig = (GString *) dkim_sigs->data;
+
+                                       if (task->flags & RSPAMD_TASK_FLAG_MILTER) {
+                                               folded_header = rspamd_header_value_fold ("DKIM-Signature",
+                                                               dkim_sig->str, 80, RSPAMD_TASK_NEWLINES_LF, NULL);
+                                       }
+                                       else {
+                                               folded_header = rspamd_header_value_fold ("DKIM-Signature",
+                                                               dkim_sig->str, 80, task->nlines_type, NULL);
+                                       }
+
+                                       ucl_array_append (ar,
+                                                       ucl_object_fromstring_common (folded_header->str,
+                                                                       folded_header->len, UCL_STRING_RAW));
+                                       g_string_free (folded_header, TRUE);
+                               }
+
+                               ucl_object_insert_key (top,
+                                               ar,
+                                               "dkim-signature", 0,
+                                               false);
                        }
                        else {
-                               folded_header = rspamd_header_value_fold ("DKIM-Signature",
-                                               dkim_sig->str, 80, task->nlines_type, NULL);
+                               /* Single DKIM signature */
+                               GString *folded_header;
+                               dkim_sig = (GString *) dkim_sigs->data;
+
+                               if (task->flags & RSPAMD_TASK_FLAG_MILTER) {
+                                       folded_header = rspamd_header_value_fold ("DKIM-Signature",
+                                                       dkim_sig->str, 80, RSPAMD_TASK_NEWLINES_LF, NULL);
+                               }
+                               else {
+                                       folded_header = rspamd_header_value_fold ("DKIM-Signature",
+                                                       dkim_sig->str, 80, task->nlines_type, NULL);
+                               }
+
+                               ucl_object_insert_key (top,
+                                               ucl_object_fromstring_common (folded_header->str,
+                                                               folded_header->len, UCL_STRING_RAW),
+                                               "dkim-signature", 0, false);
+                               g_string_free (folded_header, TRUE);
                        }
-                       /*
-                        * According to milter docs, we need to be extra careful
-                        * when folding headers:
-                        * Neither the name nor the value of the header is checked for standards
-                        * compliance. However, each line of the header must be under 2048
-                        * characters and should be under 998 characters.
-                        * If longer headers are needed, make them multi-line.
-                        * To make a multi-line header, insert a line feed (ASCII 0x0a, or \n
-                        * in C) followed by at least one whitespace character such as a
-                        * space (ASCII 0x20) or tab (ASCII 0x09, or \t in C).
-                        * The line feed should NOT be preceded by a carriage return (ASCII 0x0d);
-                        * the MTA will add this automatically.
-                        * It is the filter writer's responsibility to ensure that no
-                        * standards are violated.
-                        */
-                       ucl_object_insert_key (top,
-                                       ucl_object_fromstring_common (folded_header->str,
-                                                       folded_header->len, UCL_STRING_RAW),
-                                                       "dkim-signature", 0, false);
-                       g_string_free (folded_header, TRUE);
                }
        }