Add ability to use proxies to connect to hostnames when there is no nameserver.

[tinc] / src / protocol_auth.c

diff --git a/src/protocol_auth.c b/src/protocol_auth.c
index e5c4c16..e54fe23 100644 (file)
--- a/src/protocol_auth.c
+++ b/src/protocol_auth.c
@@ -1,7 +1,7 @@
 /*
     protocol_auth.c -- handle the meta-protocol, authentication
     Copyright (C) 1999-2005 Ivo Timmermans,
-                  2000-2012 Guus Sliepen <guus@tinc-vpn.org>
+                  2000-2014 Guus Sliepen <guus@tinc-vpn.org>
 
     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
@@ -36,49 +36,12 @@
 #include "netutl.h"
 #include "node.h"
 #include "protocol.h"
+#include "proxy.h"
 #include "utils.h"
 #include "xalloc.h"
 
-static bool send_proxyrequest(connection_t *c) {
-       switch(proxytype) {
-               case PROXY_HTTP: {
-                       char *host;
-                       char *port;
-
-                       sockaddr2str(&c->address, &host, &port);
-                       send_request(c, "CONNECT %s:%s HTTP/1.1\r\n\r", host, port);
-                       free(host);
-                       free(port);
-                       return true;
-               }
-               case PROXY_SOCKS4: {
-                       if(c->address.sa.sa_family != AF_INET) {
-                               logger(LOG_ERR, "Cannot connect to an IPv6 host through a SOCKS 4 proxy!");
-                               return false;
-                       }
-                       char s4req[9 + (proxyuser ? strlen(proxyuser) : 0)];
-                       s4req[0] = 4;
-                       s4req[1] = 1;
-                       memcpy(s4req + 2, &c->address.in.sin_port, 2);
-                       memcpy(s4req + 4, &c->address.in.sin_addr, 4);
-                       if(proxyuser)
-                               strcpy(s4req + 8, proxyuser);
-                       s4req[sizeof s4req - 1] = 0;
-                       c->tcplen = 8;
-                       return send_meta(c, s4req, sizeof s4req);
-               }
-               case PROXY_SOCKS4A:
-               case PROXY_SOCKS5:
-                       logger(LOG_ERR, "Proxy type not implemented yet");
-                       return false;
-               default:
-                       logger(LOG_ERR, "Unknown proxy type");
-                       return false;
-       }
-}
-
 bool send_id(connection_t *c) {
-       if(proxytype)
+       if(proxytype && c->outgoing)
                if(!send_proxyrequest(c))
                        return false;
 
@@ -167,7 +130,12 @@ bool send_metakey(connection_t *c) {
 
        /* Copy random data to the buffer */
 
-       RAND_pseudo_bytes((unsigned char *)c->outkey, len);
+       if (1 != RAND_bytes((unsigned char *)c->outkey, len)) {
+               int err = ERR_get_error();
+               logger(LOG_ERR, "Failed to generate meta key (%s)", ERR_error_string(err, NULL));
+               return false;
+       }
+
 
        /* The message we send must be smaller than the modulus of the RSA key.
           By definition, for a key of k bits, the following formula holds:
@@ -196,8 +164,8 @@ bool send_metakey(connection_t *c) {
         */
 
        if(RSA_public_encrypt(len, (unsigned char *)c->outkey, (unsigned char *)buffer, c->rsa_key, RSA_NO_PADDING) != len) {
-               logger(LOG_ERR, "Error during encryption of meta key for %s (%s)",
-                          c->name, c->hostname);
+               logger(LOG_ERR, "Error during encryption of meta key for %s (%s): %s",
+                          c->name, c->hostname, ERR_error_string(ERR_get_error(), NULL));
                return false;
        }
 
@@ -260,13 +228,16 @@ bool metakey_h(connection_t *c) {
 
        /* Convert the challenge from hexadecimal back to binary */
 
-       hex2bin(buffer, buffer, len);
+       if(!hex2bin(buffer, buffer, len)) {
+               logger(LOG_ERR, "Got bad %s from %s(%s): %s", "METAKEY", c->name, c->hostname, "invalid key");
+               return false;
+       }
 
        /* Decrypt the meta key */
 
        if(RSA_private_decrypt(len, (unsigned char *)buffer, (unsigned char *)c->inkey, myself->connection->rsa_key, RSA_NO_PADDING) != len) {  /* See challenge() */
-               logger(LOG_ERR, "Error during decryption of meta key for %s (%s)",
-                          c->name, c->hostname);
+               logger(LOG_ERR, "Error during decryption of meta key for %s (%s): %s",
+                          c->name, c->hostname, ERR_error_string(ERR_get_error(), NULL));
                return false;
        }
 
@@ -340,7 +311,11 @@ bool send_challenge(connection_t *c) {
 
        /* Copy random data to the buffer */
 
-       RAND_pseudo_bytes((unsigned char *)c->hischallenge, len);
+       if (1 != RAND_bytes((unsigned char *)c->hischallenge, len)) {
+               int err = ERR_get_error();
+               logger(LOG_ERR, "Failed to generate challenge (%s)", ERR_error_string(err, NULL));
+               return false; // Do not send predictable challenges, let connection attempt fail.
+       }
 
        /* Convert to hex */
 
@@ -378,7 +353,10 @@ bool challenge_h(connection_t *c) {
 
        /* Convert the challenge from hexadecimal back to binary */
 
-       hex2bin(buffer, c->mychallenge, len);
+       if(!hex2bin(buffer, c->mychallenge, len)) {
+               logger(LOG_ERR, "Got bad %s from %s(%s): %s", "CHALLENGE", c->name, c->hostname, "invalid challenge");
+               return false;
+       }
 
        c->allow_request = CHAL_REPLY;
 
@@ -432,7 +410,10 @@ bool chal_reply_h(connection_t *c) {
 
        /* Convert the hash to binary format */
 
-       hex2bin(hishash, hishash, c->outdigest->md_size);
+       if(!hex2bin(hishash, hishash, c->outdigest->md_size)) {
+               logger(LOG_ERR, "Got bad %s from %s(%s): %s", "CHAL_REPLY", c->name, c->hostname, "invalid hash");
+               return false;
+       }
 
        /* Calculate the hash from the challenge we sent */