[Fix] Fix parsing of URLs with spaces and other bad chars

diff --git a/src/libserver/html.c b/src/libserver/html.c
index af91ab39cff8dd44ffe9626a1238e72a37d3b49d..a26f40ed73b95d3cc1da1fedd8bdffbb53f13492 100644 (file)
--- a/src/libserver/html.c
+++ b/src/libserver/html.c
@@ -1223,8 +1223,11 @@ rspamd_html_process_url (rspamd_mempool_t *pool, const gchar *start, guint len,
        gchar *decoded;
        gint rc;
        gsize decoded_len;
-       const gchar *p;
-       gchar *t, *h;
+       const gchar *p, *s;
+       gchar *d;
+       guint i, dlen;
+       gboolean has_bad_chars = FALSE;
+       static const gchar hexdigests[16] = "0123456789abcdef";
 
        p = start;
 
@@ -1253,36 +1256,55 @@ rspamd_html_process_url (rspamd_mempool_t *pool, const gchar *start, guint len,
                }
        }
 
-       /* Also we need to perform url decode */
-       decoded = rspamd_mempool_alloc (pool, len + 1);
-       rspamd_strlcpy (decoded, start, len + 1);
-       decoded_len = rspamd_decode_url (decoded, start, len);
+       s = start;
+       dlen = 0;
 
-       /* We also need to remove all internal newlines */
-       t = decoded;
-       h = t;
-
-       while (*h) {
-               if (*h == '\r' || *h == '\n') {
-                       h ++;
-                       decoded_len --;
+       for (i = 0; i < len; i ++) {
+               if (G_UNLIKELY (!g_ascii_isgraph (s[i]))) {
+                       dlen += 3;
                }
                else {
-                       *t++ = *h++;
+                       dlen ++;
                }
        }
-       *t = *h;
 
-       if (comp) {
-               comp->start = decoded;
-               comp->len = decoded_len;
+       decoded = rspamd_mempool_alloc (pool, dlen + 1);
+       d = decoded;
+
+       /* We also need to remove all internal newlines and encode unsafe characters */
+       for (i = 0; i < len; i ++) {
+               if (G_UNLIKELY (s[i] == '\r' || s[i] == '\n')) {
+                       continue;
+               }
+               else if (G_UNLIKELY (!g_ascii_isgraph (s[i]))) {
+                       /* URL encode */
+                       *d++ = '%';
+                       *d++ = hexdigests[(s[i] >> 4) & 0xf];
+                       *d++ = hexdigests[s[i] & 0xf];
+                       has_bad_chars = TRUE;
+               }
+               else {
+                       *d++ = s[i];
+               }
        }
 
+       *d = '\0';
+
        url = rspamd_mempool_alloc (pool, sizeof (*url));
-       rc = rspamd_url_parse (url, decoded, decoded_len, pool);
+       rc = rspamd_url_parse (url, decoded, d - decoded, pool);
 
        if (rc == URI_ERRNO_OK) {
+               if (has_bad_chars) {
+                       url->flags |= RSPAMD_URL_FLAG_OBSCURED;
+               }
 
+               decoded = url->string;
+               decoded_len = url->urllen;
+
+               if (comp) {
+                       comp->start = decoded;
+                       comp->len = decoded_len;
+               }
                /* Spaces in href usually mean an attempt to obfuscate URL */
                /* See https://github.com/vstakhov/rspamd/issues/593 */
 #if 0