Disable RC4.

[tlsproxy/tlsproxy.git] / src / connection.c

diff --git a/src/connection.c b/src/connection.c
index e675a825c72b15297af939bb118093c3c0f2bb9e..fb854da4536937ae43f136ff6f418cbbaf776698 100644 (file)
--- a/src/connection.c
+++ b/src/connection.c
@@ -1,7 +1,7 @@
 /*
  * Handle connections.
  *
- * Copyright (C) 2011-2013  Simon Ruderich
+ * Copyright (C) 2011-2014  Simon Ruderich
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -26,6 +26,7 @@
 #include <limits.h>
 #include <netdb.h>
 #include <poll.h>
+#include <sys/socket.h>
 #include <unistd.h>
 
 #include <gnutls/x509.h>
@@ -40,7 +41,8 @@
 /* Format string used to send HTTP/1.0 error responses to the client.
  *
  * %s is used 5 times, first is the error code, then additional headers, next
- * two are the error code (no %n$s!), the last is the message. */
+ * two are the error code (no %n$s which is not in C98!), the last is the
+ * message. */
 #define HTTP_RESPONSE_FORMAT "HTTP/1.0 %s\r\n\
 Content-Type: text/html; charset=US-ASCII\r\n\
 %s\r\n\
@@ -100,9 +102,9 @@ void handle_connection(int client_socket) {
     int version_minor; /* x in HTTP/1.x */
     int result;
 
-    /* client_x509_cred is used when talking to the client (acting as a TSL
+    /* client_x509_cred is used when talking to the client (acting as a TLS
      * server), server_x509_cred is used when talking to the server (acting as
-     * a TSL client). */
+     * a TLS client). */
     gnutls_certificate_credentials_t client_x509_cred, server_x509_cred;
 
     gnutls_session_t client_session, server_session;
@@ -205,7 +207,7 @@ void handle_connection(int client_socket) {
     LOG(DEBUG1, "connection to server established");
 
     /* If the -u option is used and we don't know this hostname's server
-     * certificate then just pass through the connection and let the client
+     * certificate, then just pass through the connection and let the client
      * verify the server certificate. */
     if (global_passthrough_unknown) {
         char path[TLSPROXY_MAX_PATH_LENGTH];
@@ -616,6 +618,7 @@ static void tls_send_invalid_cert_message(gnutls_session_t session) {
     const char msg[]   = "Server certificate validation failed, check logs.";
 
     int result;
+    ssize_t size_written;
     char buffer[sizeof(HTTP_RESPONSE_FORMAT)
                 + 3 * sizeof(error) + sizeof(msg)];
 
@@ -623,7 +626,13 @@ static void tls_send_invalid_cert_message(gnutls_session_t session) {
                                               error, "", error, error, msg);
     assert(result > 0 && (size_t)result < sizeof(buffer));
 
-    gnutls_record_send(session, buffer, strlen(buffer));
+    size_written = gnutls_record_send(session, buffer, strlen(buffer));
+    if (size_written < 0) {
+        LOG(WARNING, "tls_send_invalid_cert_message(): "
+                     "gnutls_record_send(): %s",
+                     gnutls_strerror((int)size_written));
+    }
+    /* Just an error message, no need to check if everything was written. */
 }
 
 
@@ -695,8 +704,8 @@ static int read_from_write_to(int from, int to) {
         return -1;
     }
     if (size_read != size_written) {
-        LOG(ERROR, "read_from_write_to(): only written %ld of %ld bytes!",
-                   (long int)size_written, (long int)size_read);
+        LOG(ERROR, "read_from_write_to(): only written %zu of %zu bytes!",
+                   size_written, size_read);
         return -1;
     }
 
@@ -723,8 +732,8 @@ static void transfer_data_tls(int client, int server,
     if (gnutls_record_get_max_size(server_session) < buffer_size) {
         buffer_size = gnutls_record_get_max_size(server_session);
     }
-    LOG(DEBUG2, "transfer_data_tls(): suggested buffer size: %ld",
-                (long int)buffer_size);
+    LOG(DEBUG2, "transfer_data_tls(): suggested buffer size: %zu",
+                buffer_size);
 
     for (;;) {
         int result = poll(fds, 2 /* fd count */, -1 /* no timeout */);
@@ -767,16 +776,32 @@ static int read_from_write_to_tls(gnutls_session_t from,
                                   size_t buffer_size) {
     ssize_t size_read;
     ssize_t size_written;
-    char buffer[16384];
+    char buffer[16384]; /* GnuTLS default maximum */
 
     if (buffer_size > sizeof(buffer)) {
-        LOG(WARNING, "read_from_write_to_tls(): reduced buffer size to %ld",
-                     (long int)(sizeof(buffer)));
+        LOG(WARNING, "read_from_write_to_tls(): reduced buffer size to %zu",
+                     sizeof(buffer));
         buffer_size = sizeof(buffer);
     }
 
     size_read = gnutls_record_recv(from, buffer, buffer_size);
     if (size_read < 0) {
+        /* Allow rehandshakes. As handshakes might be insecure make sure that
+         * %SAFE_RENEGOTIATION is used in GnuTLS's priority string. */
+        if (size_read == GNUTLS_E_REHANDSHAKE) {
+            int result;
+
+            LOG(DEBUG1, "server requested TLS rehandshake");
+
+            result = gnutls_handshake(from);
+            if (result != GNUTLS_E_SUCCESS) {
+                LOG(WARNING, "server TLS rehandshake failed: %s",
+                             gnutls_strerror(result));
+                return -1;
+            }
+            return 0;
+        }
+
         LOG(WARNING, "read_from_write_to_tls(): gnutls_record_recv(): %s",
                      gnutls_strerror((int)size_read));
         return -1;
@@ -792,8 +817,8 @@ static int read_from_write_to_tls(gnutls_session_t from,
         return -1;
     }
     if (size_read != size_written) {
-        LOG(ERROR, "read_from_write_to_tls(): only written %ld of %ld bytes!",
-                   (long int)size_written, (long int)size_read);
+        LOG(ERROR, "read_from_write_to_tls(): only written %zu of %zu bytes!",
+                   size_written, size_read);
         return -1;
     }
 
@@ -819,8 +844,10 @@ static int connect_to_host(const char *hostname, const char *port) {
     gai_hints.ai_socktype = SOCK_STREAM;
     gai_hints.ai_protocol = 0;
     gai_hints.ai_flags    = AI_NUMERICSERV /* given port is numeric */
+#ifdef AI_ADDRCONFIG
                           | AI_ADDRCONFIG  /* supported by this computer */
-                          | AI_V4MAPPED;   /* support IPv4 through IPv6 */
+#endif
+                          ;
     gai_return = getaddrinfo(hostname, port, &gai_hints, &gai_result);
     if (gai_return != 0) {
         if (gai_return == EAI_SYSTEM) {