Add comments for (relatively) new features bitmasks.
[privoxy.git] / parsers.c
index 1753445..1fb9983 100644 (file)
--- a/parsers.c
+++ b/parsers.c
@@ -1,4 +1,4 @@
-const char parsers_rcs[] = "$Id: parsers.c,v 1.192 2009/07/11 11:15:14 fabiankeil Exp $";
+const char parsers_rcs[] = "$Id: parsers.c,v 1.208 2009/09/06 14:10:07 fabiankeil Exp $";
 /*********************************************************************
  *
  * File        :  $Source: /cvsroot/ijbswa/current/parsers.c,v $
@@ -156,7 +156,9 @@ static jb_err server_content_disposition(struct client_state *csp, char **header
 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
 static jb_err server_save_content_length(struct client_state *csp, char **header);
 static jb_err server_keep_alive(struct client_state *csp, char **header);
+static jb_err server_proxy_connection(struct client_state *csp, char **header);
 static jb_err client_keep_alive(struct client_state *csp, char **header);
+static jb_err client_save_content_length(struct client_state *csp, char **header);
 #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
 
 static jb_err client_host_adder       (struct client_state *csp);
@@ -172,7 +174,6 @@ static jb_err create_forged_referrer(char **header, const char *hostport);
 static jb_err create_fake_referrer(char **header, const char *fake_referrer);
 static jb_err handle_conditional_hide_referrer_parameter(char **header,
    const char *host, const int parameter_conditional_block);
-static const char *get_appropiate_connection_header(const struct client_state *csp);
 static void create_content_length_header(unsigned long long content_length,
                                          char *header, size_t buffer_length);
 
@@ -204,6 +205,7 @@ static const struct parsers client_patterns[] = {
    { "if-modified-since:",       18,   client_if_modified_since },
 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
    { "Keep-Alive:",              11,   client_keep_alive },
+   { "Content-Length:",          15,   client_save_content_length },
 #else
    { "Keep-Alive:",              11,   crumble },
 #endif
@@ -231,6 +233,7 @@ static const struct parsers server_patterns[] = {
 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
    { "Content-Length:",          15, server_save_content_length },
    { "Keep-Alive:",              11, server_keep_alive },
+   { "Proxy-Connection:",        17, server_proxy_connection },
 #else
    { "Keep-Alive:",              11, crumble },
 #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
@@ -585,7 +588,7 @@ jb_err decompress_iob(struct client_state *csp)
 
    assert(bufsize >= skip_size);
    memcpy(buf, csp->iob->buf, skip_size);
-   zstr.avail_out = bufsize - skip_size;
+   zstr.avail_out = (uInt)(bufsize - skip_size);
    zstr.next_out  = (Bytef *)buf + skip_size;
 
    /* Try to decompress the whole stream in one shot. */
@@ -643,7 +646,7 @@ jb_err decompress_iob(struct client_state *csp)
           * buffer, which may be in a location different from
           * the old one.
           */
-         zstr.avail_out += bufsize - oldbufsize;
+         zstr.avail_out += (uInt)(bufsize - oldbufsize);
          zstr.next_out   = (Bytef *)tmpbuf + bufsize - zstr.avail_out;
 
          /*
@@ -652,7 +655,6 @@ jb_err decompress_iob(struct client_state *csp)
           */
          assert(zstr.avail_out == tmpbuf + bufsize - (char *)zstr.next_out);
          assert((char *)zstr.next_out == tmpbuf + ((char *)oldnext_out - buf));
-         assert(zstr.avail_out > 0U);
 
          buf = tmpbuf;
       }
@@ -1665,12 +1667,37 @@ static jb_err server_keep_alive(struct client_state *csp, char **header)
             "Server keep-alive timeout is %u. Sticking with %u.",
             keep_alive_timeout, csp->server_connection.keep_alive_timeout);
       }
+      csp->flags |= CSP_FLAG_SERVER_KEEP_ALIVE_TIMEOUT_SET;
    }
 
    return JB_ERR_OK;
 }
 
 
+/*********************************************************************
+ *
+ * Function    :  server_proxy_connection
+ *
+ * Description :  Figures out whether or not we should add a
+ *                Proxy-Connection header.
+ *
+ * Parameters  :
+ *          1  :  csp = Current client state (buffers, headers, etc...)
+ *          2  :  header = On input, pointer to header to modify.
+ *                On output, pointer to the modified header, or NULL
+ *                to remove the header.  This function frees the
+ *                original string if necessary.
+ *
+ * Returns     :  JB_ERR_OK.
+ *
+ *********************************************************************/
+static jb_err server_proxy_connection(struct client_state *csp, char **header)
+{
+   csp->flags |= CSP_FLAG_SERVER_PROXY_CONNECTION_HEADER_SET;
+   return JB_ERR_OK;
+}
+
+
 /*********************************************************************
  *
  * Function    :  client_keep_alive
@@ -1692,6 +1719,14 @@ static jb_err client_keep_alive(struct client_state *csp, char **header)
    unsigned int keep_alive_timeout;
    const char *timeout_position = strstr(*header, ": ");
 
+   if (!(csp->config->feature_flags & RUNTIME_FEATURE_CONNECTION_KEEP_ALIVE))
+   {
+      log_error(LOG_LEVEL_HEADER,
+         "keep-alive support is disabled. Crunching: %s.", *header);
+      freez(*header);
+      return JB_ERR_OK;
+   }
+
    if ((NULL == timeout_position)
     || (1 != sscanf(timeout_position, ": %u", &keep_alive_timeout)))
    {
@@ -1717,6 +1752,76 @@ static jb_err client_keep_alive(struct client_state *csp, char **header)
 
    return JB_ERR_OK;
 }
+
+
+/*********************************************************************
+ *
+ * Function    :  get_content_length
+ *
+ * Description :  Gets the content length specified in a
+ *                Content-Length header.
+ *
+ * Parameters  :
+ *          1  :  header = The Content-Length header.
+ *          2  :  length = Storage to return the value.
+ *
+ * Returns     :  JB_ERR_OK on success, or
+ *                JB_ERR_PARSE if no value is recognized.
+ *
+ *********************************************************************/
+static jb_err get_content_length(const char *header, unsigned long long *length)
+{
+   assert(header[14] == ':');
+
+#ifdef _WIN32
+   assert(sizeof(unsigned long long) > 4);
+   if (1 != sscanf(header+14, ": %I64u", length))
+#else
+   if (1 != sscanf(header+14, ": %llu", length))
+#endif
+   {
+      return JB_ERR_PARSE;
+   }
+
+   return JB_ERR_OK;
+}
+
+
+/*********************************************************************
+ *
+ * Function    :  client_save_content_length
+ *
+ * Description :  Save the Content-Length sent by the client.
+ *
+ * Parameters  :
+ *          1  :  csp = Current client state (buffers, headers, etc...)
+ *          2  :  header = On input, pointer to header to modify.
+ *                On output, pointer to the modified header, or NULL
+ *                to remove the header.  This function frees the
+ *                original string if necessary.
+ *
+ * Returns     :  JB_ERR_OK on success, or
+ *                JB_ERR_MEMORY on out-of-memory error.
+ *
+ *********************************************************************/
+static jb_err client_save_content_length(struct client_state *csp, char **header)
+{
+   unsigned long long content_length = 0;
+
+   assert(*(*header+14) == ':');
+
+   if (JB_ERR_OK != get_content_length(*header, &content_length))
+   {
+      log_error(LOG_LEVEL_ERROR, "Crunching invalid header: %s", *header);
+      freez(*header);
+   }
+   else
+   {
+      csp->expected_client_content_length = content_length;
+   }
+
+   return JB_ERR_OK;
+}
 #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
 
 
@@ -1742,43 +1847,64 @@ static jb_err client_keep_alive(struct client_state *csp, char **header)
  *********************************************************************/
 static jb_err client_connection(struct client_state *csp, char **header)
 {
-   const char *wanted_header = get_appropiate_connection_header(csp);
+   static const char connection_close[] = "Connection: close";
 
-   if (strcmpic(*header, wanted_header))
+   if (!strcmpic(*header, connection_close))
    {
 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
-      if (!(csp->config->feature_flags & RUNTIME_FEATURE_CONNECTION_SHARING))
+      if ((csp->config->feature_flags & RUNTIME_FEATURE_CONNECTION_SHARING))
       {
-         log_error(LOG_LEVEL_HEADER,
-            "Keeping the client header '%s' around. "
-            "The connection will not be kept alive.",
-            *header);
+          if (!strcmpic(csp->http->ver, "HTTP/1.1"))
+          {
+             log_error(LOG_LEVEL_HEADER,
+                "Removing \'%s\' to imply keep-alive.", *header);
+             freez(*header);
+          }
+          else
+          {
+             char *old_header = *header;
+
+             *header = strdup("Connection: keep-alive");
+             if (header == NULL)
+             {
+                return JB_ERR_MEMORY;
+             }
+             log_error(LOG_LEVEL_HEADER,
+                "Replaced: \'%s\' with \'%s\'", old_header, *header);
+             freez(old_header);
+          }
       }
       else
-#endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
       {
-         char *old_header = *header;
-
-         *header = strdup(wanted_header);
-         if (header == NULL)
-         {
-            return JB_ERR_MEMORY;
-         }
          log_error(LOG_LEVEL_HEADER,
-            "Replaced: \'%s\' with \'%s\'", old_header, *header);
-         freez(old_header);
+            "Keeping the client header '%s' around. "
+            "The connection will not be kept alive.",
+            *header);
+         csp->flags &= ~CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE;
       }
    }
-#ifdef FEATURE_CONNECTION_KEEP_ALIVE
-   else
+   else if ((csp->config->feature_flags & RUNTIME_FEATURE_CONNECTION_KEEP_ALIVE))
    {
       log_error(LOG_LEVEL_HEADER,
          "Keeping the client header '%s' around. "
          "The server connection will be kept alive if possible.",
          *header);
       csp->flags |= CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE;
-   }
 #endif  /* def FEATURE_CONNECTION_KEEP_ALIVE */
+   }
+   else
+   {
+      char *old_header = *header;
+
+      *header = strdup(connection_close);
+      if (header == NULL)
+      {
+         return JB_ERR_MEMORY;
+      }
+      log_error(LOG_LEVEL_HEADER,
+         "Replaced: \'%s\' with \'%s\'", old_header, *header);
+      freez(old_header);
+   }
 
    /* Signal client_connection_adder() to return early. */
    csp->flags |= CSP_FLAG_CLIENT_CONNECTION_HEADER_SET;
@@ -2163,11 +2289,7 @@ static jb_err server_save_content_length(struct client_state *csp, char **header
 
    assert(*(*header+14) == ':');
 
-#ifdef _WIN32
-   if (1 != sscanf(*header+14, ": %I64u", &content_length))
-#else
-   if (1 != sscanf(*header+14, ": %llu", &content_length))
-#endif
+   if (JB_ERR_OK != get_content_length(*header, &content_length))
    {
       log_error(LOG_LEVEL_ERROR, "Crunching invalid header: %s", *header);
       freez(*header);
@@ -3466,17 +3588,8 @@ static jb_err server_connection_adder(struct client_state *csp)
 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
     && !(csp->flags & CSP_FLAG_SERVER_SOCKET_TAINTED)
 #endif
-    && (csp->http->status == 200)
        )
    {
-      /*
-       * XXX: not doing this for status codes other than 200 works
-       * around problems with broken servers that will keep the
-       * connection open, but terminate the connection when the
-       * next request arrives. Once we are able to figure out which
-       * requests are safe to send again, this will probably no
-       * longer be necessary.
-       */
       log_error(LOG_LEVEL_HEADER, "A HTTP/1.1 response "
          "without Connection header implies keep-alive.");
       csp->flags |= CSP_FLAG_SERVER_CONNECTION_KEEP_ALIVE;
@@ -3511,7 +3624,8 @@ static jb_err server_proxy_connection_adder(struct client_state *csp)
    jb_err err = JB_ERR_OK;
 
    if ((csp->flags & CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE)
-    && !(csp->flags & CSP_FLAG_SERVER_SOCKET_TAINTED))
+    && !(csp->flags & CSP_FLAG_SERVER_SOCKET_TAINTED)
+    && !(csp->flags & CSP_FLAG_SERVER_PROXY_CONNECTION_HEADER_SET))
    {
       log_error(LOG_LEVEL_HEADER, "Adding: %s", proxy_connection_header);
       err = enlist(csp->headers, proxy_connection_header);
@@ -3619,8 +3733,7 @@ static jb_err server_http(struct client_state *csp, char **header)
  * Function    :  server_set_cookie
  *
  * Description :  Handle the server "cookie" header properly.
- *                Log cookie to the jar file.  Then "crunch",
- *                accept or rewrite it to a session cookie.
+ *                Crunch, accept or rewrite it to a session cookie.
  *                Called from `sed'.
  *
  *                TODO: Allow the user to specify a new expiration
@@ -4103,37 +4216,6 @@ static jb_err handle_conditional_hide_referrer_parameter(char **header,
 }
 
 
-/*********************************************************************
- *
- * Function    :  get_appropiate_connection_header
- *
- * Description :  Returns an appropiate Connection header
- *                depending on whether or not we try to keep
- *                the connection to the server alive.
- *
- * Parameters  :
- *          1  :  csp = Current client state (buffers, headers, etc...)
- *
- * Returns     :  Pointer to statically allocated header buffer.
- *
- *********************************************************************/
-static const char *get_appropiate_connection_header(const struct client_state *csp)
-{
-   static const char connection_keep_alive[] = "Connection: keep-alive";
-   static const char connection_close[] = "Connection: close";
-
-   if ((csp->config->feature_flags & RUNTIME_FEATURE_CONNECTION_KEEP_ALIVE)
-#ifdef FEATURE_CONNECTION_KEEP_ALIVE
-    && !(csp->flags & CSP_FLAG_SERVER_SOCKET_TAINTED)
-#endif
-    && (csp->http->ssl == 0))
-   {
-      return connection_keep_alive;
-   }
-   return connection_close;
-}
-
-
 /*********************************************************************
  *
  * Function    :  create_content_length_header