[Minor] Some more adjustments to CTE detection

diff --git a/src/libmime/mime_parser.c b/src/libmime/mime_parser.c
index c6c80e3f0988eb6af77a96284b3e5b2343f3b2fb..54c490109fe7d623f97c92d7ceac82daf34e23e2 100644 (file)
--- a/src/libmime/mime_parser.c
+++ b/src/libmime/mime_parser.c
@@ -149,8 +149,8 @@ static enum rspamd_cte
 rspamd_mime_part_get_cte_heuristic (struct rspamd_task *task,
                struct rspamd_mime_part *part)
 {
-       const guint check_len = 80;
-       guint real_len, nspaces = 0, neqsign = 0, n8bit = 0;
+       const guint check_len = 128;
+       guint real_len, nspaces = 0, neqsign = 0, n8bit = 0, nqpencoded = 0;
        gboolean b64_chars = TRUE;
        const guchar *p, *end;
        enum rspamd_cte ret = RSPAMD_CTE_UNKNOWN;
@@ -163,6 +163,18 @@ rspamd_mime_part_get_cte_heuristic (struct rspamd_task *task,
                p ++;
        }
 
+       if (end > p + 2) {
+               if (*(end - 1) == '=') {
+                       neqsign ++;
+                       end --;
+               }
+
+               if (*(end - 1) == '=') {
+                       neqsign ++;
+                       end --;
+               }
+       }
+
        if (end - p > real_len) {
                end = p + real_len;
        }
@@ -178,6 +190,14 @@ rspamd_mime_part_get_cte_heuristic (struct rspamd_task *task,
                }
                else if (*p == '=') {
                        neqsign ++;
+                       p ++;
+
+                       if (p + 2 < end && g_ascii_isxdigit (*p) && g_ascii_isxdigit (*(p + 1))) {
+                               p ++;
+                               nqpencoded ++;
+                       }
+
+                       continue;
                }
                else if (*p >= 0x80) {
                        n8bit ++;
@@ -194,7 +214,7 @@ rspamd_mime_part_get_cte_heuristic (struct rspamd_task *task,
                ret = RSPAMD_CTE_B64;
        }
        else if (n8bit == 0) {
-               if (neqsign > 2 && nspaces > 2) {
+               if (neqsign > 2 && nqpencoded > 2) {
                        ret = RSPAMD_CTE_QP;
                }
                else {