[Minor] More heuristics in HTML urls detection

diff --git a/src/libserver/html.c b/src/libserver/html.c
index 8ade5a61e4747bb627c4109408c52ad959b27985..3353db7b7520e63db40d1b5a83ecbc47a6db721c 100644 (file)
--- a/src/libserver/html.c
+++ b/src/libserver/html.c
@@ -1301,7 +1301,7 @@ rspamd_html_process_url (rspamd_mempool_t *pool, const gchar *start, guint len,
        gchar *decoded;
        gint rc;
        gsize decoded_len;
-       const gchar *p, *s;
+       const gchar *p, *s, *prefix = "http://";
        gchar *d;
        guint i, dlen;
        gboolean has_bad_chars = FALSE, no_prefix = FALSE;
@@ -1347,44 +1347,50 @@ rspamd_html_process_url (rspamd_mempool_t *pool, const gchar *start, guint len,
        }
 
        if (rspamd_substring_search (start, len, "://", 3) == -1) {
-               /* We have no prefix */
-               dlen += sizeof ("http://") - 1;
-               no_prefix = TRUE;
+               if (len >= sizeof ("mailto:") &&
+                               (memcmp (start, "mailto:", sizeof ("mailto:") - 1) == 0 ||
+                                               memcmp (start, "tel:", sizeof ("tel:") - 1) == 0)) {
+                       /* Exclusion, has valid but 'strange' prefix */
+               }
+               else {
+                       for (i = 0; i < len; i ++) {
+                               if (!((s[i] & 0x80) || g_ascii_isalnum (s[i]))) {
+                                       if (i == 0 && len > 2 && s[i] == '/'  && s[i + 1] == '/') {
+                                               prefix = "http:";
+                                               dlen += sizeof ("http:") - 1;
+                                               no_prefix = TRUE;
+                                       }
+                                       else if (s[i] == '@') {
+                                               /* Likely email prefix */
+                                               prefix = "mailto://";
+                                               dlen += sizeof ("mailto://") - 1;
+                                               no_prefix = TRUE;
+                                       }
+                                       else {
+                                               if (i == 0) {
+                                                       /* No valid data */
+                                                       return NULL;
+                                               }
+                                       }
+
+                                       break;
+                               }
+                       }
+
+                       if (!no_prefix) {
+                               no_prefix = TRUE;
+                               dlen += strlen (prefix);
+                       }
+               }
        }
 
        decoded = rspamd_mempool_alloc (pool, dlen + 1);
        d = decoded;
 
        if (no_prefix) {
-               if (s[0] == '/' && (len > 2 && s[1] == '/')) {
-                       /* //bla case */
-                       memcpy (d, "http:", sizeof ("http:") - 1);
-                       d += sizeof ("http:") - 1;
-               }
-               else if (s[0] == '\\' && (len > 2 && s[1] == '\\')) {
-                       /* Likely SMB share, ignore */
-                       return NULL;
-               }
-               else {
-                       if (s[0] == '.') {
-                               /*
-                                * We have relative URL without base URL:
-                                * the former is covered by caller function which
-                                * checks for the base URL.
-                                *
-                                * In the most cases, it is caused by a broken client
-                                */
-                               return NULL;
-                       }
-                       else if ((s[0] & 0x80) || g_ascii_isalnum (s[0])) {
-                               memcpy (d, "http://", sizeof ("http://") - 1);
-                               d += sizeof ("http://") - 1;
-                       }
-                       else {
-                               /* Some crap */
-                               return NULL;
-                       }
-               }
+               gsize plen = strlen (prefix);
+               memcpy (d, prefix, plen);
+               d += plen;
        }
 
        /*