2 meta.c -- handle the meta communication
3 Copyright (C) 2000-2006 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
17 along with this program; if not, write to the Free Software
18 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
25 #include <openssl/err.h>
26 #include <openssl/evp.h>
29 #include "connection.h"
37 bool send_meta(connection_t *c, const char *buffer, int length)
44 ifdebug(META) logger(LOG_DEBUG, _("Sending %d bytes of metadata to %s (%s)"), length,
45 c->name, c->hostname);
48 c->last_flushed_time = now;
49 if(event_add(&c->outev, NULL) < 0) {
50 logger(LOG_EMERG, _("event_add failed: %s"), strerror(errno));
55 /* Find room in connection's buffer */
56 if(length + c->outbuflen > c->outbufsize) {
57 c->outbufsize = length + c->outbuflen;
58 c->outbuf = xrealloc(c->outbuf, c->outbufsize);
61 if(length + c->outbuflen + c->outbufstart > c->outbufsize) {
62 memmove(c->outbuf, c->outbuf + c->outbufstart, c->outbuflen);
66 /* Add our data to buffer */
67 if(c->status.encryptout) {
68 result = EVP_EncryptUpdate(c->outctx, (unsigned char *)c->outbuf + c->outbufstart + c->outbuflen,
69 &outlen, (unsigned char *)buffer, length);
70 if(!result || outlen < length) {
71 logger(LOG_ERR, _("Error while encrypting metadata to %s (%s): %s"),
72 c->name, c->hostname, ERR_error_string(ERR_get_error(), NULL));
74 } else if(outlen > length) {
75 logger(LOG_EMERG, _("Encrypted data too long! Heap corrupted!"));
78 c->outbuflen += outlen;
80 memcpy(c->outbuf + c->outbufstart + c->outbuflen, buffer, length);
81 c->outbuflen += length;
87 void flush_meta(int fd, short events, void *data)
89 connection_t *c = data;
92 ifdebug(META) logger(LOG_DEBUG, _("Flushing %d bytes to %s (%s)"),
93 c->outbuflen, c->name, c->hostname);
96 result = send(c->socket, c->outbuf + c->outbufstart, c->outbuflen, 0);
98 if(!errno || errno == EPIPE) {
99 ifdebug(CONNECTIONS) logger(LOG_NOTICE, _("Connection closed by %s (%s)"),
100 c->name, c->hostname);
101 } else if(errno == EINTR) {
104 } else if(errno == EWOULDBLOCK) {
105 ifdebug(CONNECTIONS) logger(LOG_DEBUG, _("Flushing %d bytes to %s (%s) would block"),
106 c->outbuflen, c->name, c->hostname);
110 logger(LOG_ERR, _("Flushing meta data to %s (%s) failed: %s"), c->name,
111 c->hostname, strerror(errno));
114 terminate_connection(c, c->status.active);
118 c->outbufstart += result;
119 c->outbuflen -= result;
122 event_del(&c->outev);
124 c->outbufstart = 0; /* avoid unnecessary memmoves */
127 void broadcast_meta(connection_t *from, const char *buffer, int length)
134 for(node = connection_tree->head; node; node = node->next) {
137 if(c != from && c->status.active)
138 send_meta(c, buffer, length);
142 bool receive_meta(connection_t *c)
144 int oldlen, i, result;
145 int lenin, lenout, reqlen;
146 bool decrypted = false;
147 char inbuf[MAXBUFSIZE];
152 - Read as much as possible from the TCP socket in one go.
154 - Check if a full request is in the input buffer.
155 - If yes, process request and remove it from the buffer,
157 - If not, keep stuff in buffer and exit.
160 lenin = recv(c->socket, c->buffer + c->buflen, MAXBUFSIZE - c->buflen, 0);
163 if(!lenin || !errno) {
164 ifdebug(CONNECTIONS) logger(LOG_NOTICE, _("Connection closed by %s (%s)"),
165 c->name, c->hostname);
166 } else if(errno == EINTR)
169 logger(LOG_ERR, _("Metadata socket read error for %s (%s): %s"),
170 c->name, c->hostname, strerror(errno));
181 if(c->status.decryptin && !decrypted) {
182 result = EVP_DecryptUpdate(c->inctx, (unsigned char *)inbuf, &lenout, (unsigned char *)c->buffer + oldlen, lenin);
183 if(!result || lenout != lenin) {
184 logger(LOG_ERR, _("Error while decrypting metadata from %s (%s): %s"),
185 c->name, c->hostname, ERR_error_string(ERR_get_error(), NULL));
188 memcpy(c->buffer + oldlen, inbuf, lenin);
192 /* Are we receiving a TCPpacket? */
195 if(c->tcplen <= c->buflen) {
196 receive_tcppacket(c, c->buffer, c->tcplen);
198 c->buflen -= c->tcplen;
199 lenin -= c->tcplen - oldlen;
200 memmove(c->buffer, c->buffer + c->tcplen, c->buflen);
209 /* Otherwise we are waiting for a request */
213 for(i = oldlen; i < c->buflen; i++) {
214 if(c->buffer[i] == '\n') {
215 c->buffer[i] = '\0'; /* replace end-of-line by end-of-string so we can use sscanf */
223 if(!receive_request(c))
227 lenin -= reqlen - oldlen;
228 memmove(c->buffer, c->buffer + reqlen, c->buflen);
236 if(c->buflen >= MAXBUFSIZE) {
237 logger(LOG_ERR, _("Metadata read buffer overflow for %s (%s)"),
238 c->name, c->hostname);
242 c->last_ping_time = now;