2 meta.c -- handle the meta communication
3 Copyright (C) 2000-2009 Guus Sliepen <guus@tinc-vpn.org>,
4 2000-2005 Ivo Timmermans
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License along
17 with this program; if not, write to the Free Software Foundation, Inc.,
18 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
23 #include <openssl/err.h>
24 #include <openssl/evp.h>
27 #include "connection.h"
35 bool send_meta(connection_t *c, const char *buffer, int length) {
42 logger(LOG_ERR, _("send_meta() called with NULL pointer!"));
46 ifdebug(META) logger(LOG_DEBUG, _("Sending %d bytes of metadata to %s (%s)"), length,
47 c->name, c->hostname);
50 c->last_flushed_time = now;
52 /* Find room in connection's buffer */
53 if(length + c->outbuflen > c->outbufsize) {
54 c->outbufsize = length + c->outbuflen;
55 c->outbuf = xrealloc(c->outbuf, c->outbufsize);
58 if(length + c->outbuflen + c->outbufstart > c->outbufsize) {
59 memmove(c->outbuf, c->outbuf + c->outbufstart, c->outbuflen);
63 /* Add our data to buffer */
64 if(c->status.encryptout) {
65 result = EVP_EncryptUpdate(c->outctx, (unsigned char *)c->outbuf + c->outbufstart + c->outbuflen,
66 &outlen, (unsigned char *)buffer, length);
67 if(!result || outlen < length) {
68 logger(LOG_ERR, _("Error while encrypting metadata to %s (%s): %s"),
69 c->name, c->hostname, ERR_error_string(ERR_get_error(), NULL));
71 } else if(outlen > length) {
72 logger(LOG_EMERG, _("Encrypted data too long! Heap corrupted!"));
75 c->outbuflen += outlen;
77 memcpy(c->outbuf + c->outbufstart + c->outbuflen, buffer, length);
78 c->outbuflen += length;
84 bool flush_meta(connection_t *c) {
87 ifdebug(META) logger(LOG_DEBUG, _("Flushing %d bytes to %s (%s)"),
88 c->outbuflen, c->name, c->hostname);
91 result = send(c->socket, c->outbuf + c->outbufstart, c->outbuflen, 0);
93 if(!errno || errno == EPIPE) {
94 ifdebug(CONNECTIONS) logger(LOG_NOTICE, _("Connection closed by %s (%s)"),
95 c->name, c->hostname);
96 } else if(errno == EINTR) {
99 } else if(errno == EWOULDBLOCK) {
100 ifdebug(CONNECTIONS) logger(LOG_DEBUG, _("Flushing %d bytes to %s (%s) would block"),
101 c->outbuflen, c->name, c->hostname);
105 logger(LOG_ERR, _("Flushing meta data to %s (%s) failed: %s"), c->name,
106 c->hostname, strerror(errno));
112 c->outbufstart += result;
113 c->outbuflen -= result;
116 c->outbufstart = 0; /* avoid unnecessary memmoves */
120 void broadcast_meta(connection_t *from, const char *buffer, int length) {
126 for(node = connection_tree->head; node; node = node->next) {
129 if(c != from && c->status.active)
130 send_meta(c, buffer, length);
134 bool receive_meta(connection_t *c) {
135 int oldlen, i, result;
136 int lenin, lenout, reqlen;
137 bool decrypted = false;
138 char inbuf[MAXBUFSIZE];
143 - Read as much as possible from the TCP socket in one go.
145 - Check if a full request is in the input buffer.
146 - If yes, process request and remove it from the buffer,
148 - If not, keep stuff in buffer and exit.
151 lenin = recv(c->socket, c->buffer + c->buflen, MAXBUFSIZE - c->buflen, 0);
154 if(!lenin || !errno) {
155 ifdebug(CONNECTIONS) logger(LOG_NOTICE, _("Connection closed by %s (%s)"),
156 c->name, c->hostname);
157 } else if(errno == EINTR)
160 logger(LOG_ERR, _("Metadata socket read error for %s (%s): %s"),
161 c->name, c->hostname, strerror(errno));
172 if(c->status.decryptin && !decrypted) {
173 result = EVP_DecryptUpdate(c->inctx, (unsigned char *)inbuf, &lenout, (unsigned char *)c->buffer + oldlen, lenin);
174 if(!result || lenout != lenin) {
175 logger(LOG_ERR, _("Error while decrypting metadata from %s (%s): %s"),
176 c->name, c->hostname, ERR_error_string(ERR_get_error(), NULL));
179 memcpy(c->buffer + oldlen, inbuf, lenin);
183 /* Are we receiving a TCPpacket? */
186 if(c->tcplen <= c->buflen) {
187 receive_tcppacket(c, c->buffer, c->tcplen);
189 c->buflen -= c->tcplen;
190 lenin -= c->tcplen - oldlen;
191 memmove(c->buffer, c->buffer + c->tcplen, c->buflen);
200 /* Otherwise we are waiting for a request */
204 for(i = oldlen; i < c->buflen; i++) {
205 if(c->buffer[i] == '\n') {
206 c->buffer[i] = '\0'; /* replace end-of-line by end-of-string so we can use sscanf */
214 if(!receive_request(c))
218 lenin -= reqlen - oldlen;
219 memmove(c->buffer, c->buffer + reqlen, c->buflen);
227 if(c->buflen >= MAXBUFSIZE) {
228 logger(LOG_ERR, _("Metadata read buffer overflow for %s (%s)"),
229 c->name, c->hostname);
233 c->last_ping_time = now;