X-Git-Url: http://www.privoxy.org/gitweb/?a=blobdiff_plain;f=filters.c;h=df89372a27c482937fdf8398e938540cfb869b23;hb=20269c138d782591788097e1dbe0906788122145;hp=963adac963b17a66097e44cbe4ae910bb2e50480;hpb=303208e0fba2760a1863d71d7d2c9730f5480db4;p=privoxy.git

diff --git a/filters.c b/filters.c
index 963adac9..df89372a 100644
--- a/filters.c
+++ b/filters.c
@@ -1,4 +1,4 @@
-const char filters_rcs[] = "$Id: filters.c,v 1.145 2011/09/04 11:10:56 fabiankeil Exp $";
+const char filters_rcs[] = "$Id: filters.c,v 1.159 2011/11/06 11:52:36 fabiankeil Exp $";
 /*********************************************************************
  *
  * File        :  $Source: /cvsroot/ijbswa/current/filters.c,v $
@@ -1105,53 +1105,78 @@ char *get_last_url(char *subject, const char *redirect_mode)
       return NULL;
    }
 
-   if (0 == strcmpic(redirect_mode, "check-decoded-url"))
+   if (0 == strcmpic(redirect_mode, "check-decoded-url") && strchr(subject, '%'))
    {  
-     log_error(LOG_LEVEL_REDIRECTS, "Checking \"%s\" for encoded redirects.",
-               subject);
-
-      /* jwz: Check each parameter in the URL separately.
-              Sectionize the URL at "?" and "&",
-              then URL-decode each component,
-              and look for a URL in the decoded result.
-              Keep the last one we spot.
+      log_error(LOG_LEVEL_REDIRECTS,
+         "Checking \"%s\" for encoded redirects.", subject);
+
+      /*
+       * Check each parameter in the URL separately.
+       * Sectionize the URL at "?" and "&",
+       * go backwards through the segments, URL-decode them
+       * and look for a URL in the decoded result.
+       * Stop the search after the first match.
+       */
+      char *url_segment = NULL;
+      /*
+       * XXX: This estimate is guaranteed to be high enough as we
+       *      let ssplit() ignore empty fields, but also a bit wasteful.
        */
-      char *found = 0;
-      char *s = strdup (subject);
-      char *token = strtok (s, "?&");
-      while (token)
+      size_t max_segments = strlen(subject) / 2;
+      char **url_segments = malloc(max_segments * sizeof(char *));
+      int segments;
+
+      if (NULL == url_segments)
       {
-        char *dtoken = url_decode (token);
-        if (!dtoken) continue;
-        char *h1 = strstr (dtoken, "http://");
-        char *h2 = strstr (dtoken, "https://");
-        char *h = (h1 && h2
-                   ? (h1 < h2 ? h1 : h2)
-                   : (h1 ? h1 : h2));
-        if (h)
-        {
-          freez(found);
-          found = strdup (h);
-        }
-        token = strtok (0, "?&");
+         log_error(LOG_LEVEL_ERROR, "Out of memory while decoding URL: %s", new_url);
+         freez(subject);
+         return NULL;
       }
-      freez(s);
 
-      if (found)
+      segments = ssplit(subject, "?&", url_segments, max_segments, 1, 1);
+
+      while (segments-- > 0)
       {
-        freez(subject);
-        return found;
+         char *dtoken = url_decode(url_segments[segments]);
+         if (NULL == dtoken)
+         {
+            log_error(LOG_LEVEL_ERROR, "Unable to decode \"%s\".", url_segments[segments]);
+            continue;
+         }
+         url_segment = strstr(dtoken, "http://");
+         if (NULL == url_segment)
+         {
+            url_segment = strstr(dtoken, "https://");
+         }
+         if (NULL != url_segment)
+         {
+            url_segment = strdup(url_segment);
+            freez(dtoken);
+            if (url_segment == NULL)
+            {
+               log_error(LOG_LEVEL_ERROR,
+                  "Out of memory while searching for redirects.");
+               return NULL;
+            }
+            break;
+         }
+         freez(dtoken);
       }
+      freez(subject);
+      freez(url_segments);
 
-      freez (subject);
-      return NULL;
+      if (url_segment == NULL)
+      {
+         return NULL;
+      }
+      subject = url_segment;
+   }
+   else
+   {
+      /* Look for a URL inside this one, without decoding anything. */
+      log_error(LOG_LEVEL_REDIRECTS,
+         "Checking \"%s\" for unencoded redirects.", subject);
    }
-
-
-   /* Else, just look for a URL inside this one, without decoding anything. */
-
-   log_error(LOG_LEVEL_REDIRECTS, "Checking \"%s\" for unencoded redirects.", 
-             subject);
 
    /*
     * Find the last URL encoded in the request
@@ -1283,6 +1308,21 @@ struct http_response *redirect_url(struct client_state *csp)
    /* Did any redirect action trigger? */
    if (new_url)
    {
+      if (url_requires_percent_encoding(new_url))
+      {
+         char *encoded_url;
+         log_error(LOG_LEVEL_REDIRECTS, "Percent-encoding redirect URL: %N",
+            strlen(new_url), new_url);
+         encoded_url = percent_encode_url(new_url);
+         freez(new_url);
+         if (encoded_url == NULL)
+         {
+            return cgi_error_memory();
+         }
+         new_url = encoded_url;
+         assert(FALSE == url_requires_percent_encoding(new_url));
+      }
+
       if (0 == strcmpic(new_url, csp->http->url))
       {
          log_error(LOG_LEVEL_ERROR,
@@ -1300,8 +1340,8 @@ struct http_response *redirect_url(struct client_state *csp)
             return cgi_error_memory();
          }
 
-         if ( enlist_unique_header(rsp->headers, "Location", new_url)
-           || (NULL == (rsp->status = strdup("302 Local Redirect from Privoxy"))) )
+         if (enlist_unique_header(rsp->headers, "Location", new_url)
+           || (NULL == (rsp->status = strdup("302 Local Redirect from Privoxy"))))
          {
             freez(new_url);
             free_http_response(rsp);