/*
meta.c -- handle the meta communication
- Copyright (C) 2000-2004 Guus Sliepen <guus@tinc-vpn.org>,
- 2000-2004 Ivo Timmermans <ivo@tinc-vpn.org>
+ Copyright (C) 2000-2016 Guus Sliepen <guus@tinc-vpn.org>,
+ 2000-2005 Ivo Timmermans
+ 2006 Scott Lamb <slamb@slamb.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
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
- You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software
- Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
-
- $Id$
+ You should have received a copy of the GNU General Public License along
+ with this program; if not, write to the Free Software Foundation, Inc.,
+ 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include "system.h"
#include "meta.h"
#include "net.h"
#include "protocol.h"
-#include "system.h"
+#include "proxy.h"
#include "utils.h"
+#include "xalloc.h"
-bool send_meta(connection_t *c, const char *buffer, int length)
-{
- const char *bufp;
+bool send_meta(connection_t *c, const char *buffer, int length) {
int outlen;
- char outbuf[MAXBUFSIZE];
int result;
- cp();
+ if(!c) {
+ logger(LOG_ERR, "send_meta() called with NULL pointer!");
+ abort();
+ }
- ifdebug(META) logger(LOG_DEBUG, _("Sending %d bytes of metadata to %s (%s)"), length,
+ ifdebug(META) logger(LOG_DEBUG, "Sending %d bytes of metadata to %s (%s)", length,
c->name, c->hostname);
+ if(!c->outbuflen)
+ c->last_flushed_time = now;
+
+ /* Find room in connection's buffer */
+ if(length + c->outbuflen > c->outbufsize) {
+ c->outbufsize = length + c->outbuflen;
+ c->outbuf = xrealloc(c->outbuf, c->outbufsize);
+ }
+
+ if(length + c->outbuflen + c->outbufstart > c->outbufsize) {
+ memmove(c->outbuf, c->outbuf + c->outbufstart, c->outbuflen);
+ c->outbufstart = 0;
+ }
+
+ /* Add our data to buffer */
if(c->status.encryptout) {
- result = EVP_EncryptUpdate(c->outctx, outbuf, &outlen, buffer, length);
- if(!result || outlen != length) {
- logger(LOG_ERR, _("Error while encrypting metadata to %s (%s): %s"),
+ /* Check encryption limits */
+ if(length > c->outbudget) {
+ ifdebug(META) logger(LOG_ERR, "Byte limit exceeded for encryption to %s (%s)", c->name, c->hostname);
+ return false;
+ } else {
+ c->outbudget -= length;
+ }
+
+ result = EVP_EncryptUpdate(c->outctx, (unsigned char *)c->outbuf + c->outbufstart + c->outbuflen,
+ &outlen, (unsigned char *)buffer, length);
+ if(!result || outlen < length) {
+ logger(LOG_ERR, "Error while encrypting metadata to %s (%s): %s",
c->name, c->hostname, ERR_error_string(ERR_get_error(), NULL));
return false;
+ } else if(outlen > length) {
+ logger(LOG_EMERG, "Encrypted data too long! Heap corrupted!");
+ abort();
}
- bufp = outbuf;
- length = outlen;
- } else
- bufp = buffer;
+ c->outbuflen += outlen;
+ } else {
+ memcpy(c->outbuf + c->outbufstart + c->outbuflen, buffer, length);
+ c->outbuflen += length;
+ }
- while(length) {
- result = send(c->socket, bufp, length, 0);
+ return true;
+}
+
+bool flush_meta(connection_t *c) {
+ int result;
+
+ ifdebug(META) logger(LOG_DEBUG, "Flushing %d bytes to %s (%s)",
+ c->outbuflen, c->name, c->hostname);
+
+ while(c->outbuflen) {
+ result = send(c->socket, c->outbuf + c->outbufstart, c->outbuflen, 0);
if(result <= 0) {
if(!errno || errno == EPIPE) {
- ifdebug(CONNECTIONS) logger(LOG_NOTICE, _("Connection closed by %s (%s)"),
+ ifdebug(CONNECTIONS) logger(LOG_NOTICE, "Connection closed by %s (%s)",
c->name, c->hostname);
- } else if(errno == EINTR)
+ } else if(errno == EINTR) {
continue;
- else
- logger(LOG_ERR, _("Sending meta data to %s (%s) failed: %s"), c->name,
- c->hostname, strerror(errno));
+ } else if(sockwouldblock(sockerrno)) {
+ ifdebug(META) logger(LOG_DEBUG, "Flushing %d bytes to %s (%s) would block",
+ c->outbuflen, c->name, c->hostname);
+ return true;
+ } else {
+ logger(LOG_ERR, "Flushing meta data to %s (%s) failed: %s", c->name,
+ c->hostname, sockstrerror(sockerrno));
+ }
+
return false;
}
- bufp += result;
- length -= result;
+
+ c->outbufstart += result;
+ c->outbuflen -= result;
}
-
+
+ c->outbufstart = 0; /* avoid unnecessary memmoves */
return true;
}
-void broadcast_meta(connection_t *from, const char *buffer, int length)
-{
+void broadcast_meta(connection_t *from, const char *buffer, int length) {
avl_node_t *node;
connection_t *c;
- cp();
-
for(node = connection_tree->head; node; node = node->next) {
c = node->data;
}
}
-bool receive_meta(connection_t *c)
-{
+bool receive_meta(connection_t *c) {
int oldlen, i, result;
int lenin, lenout, reqlen;
bool decrypted = false;
char inbuf[MAXBUFSIZE];
- cp();
-
/* Strategy:
- Read as much as possible from the TCP socket in one go.
- Decrypt it.
if(lenin <= 0) {
if(!lenin || !errno) {
- ifdebug(CONNECTIONS) logger(LOG_NOTICE, _("Connection closed by %s (%s)"),
+ ifdebug(CONNECTIONS) logger(LOG_NOTICE, "Connection closed by %s (%s)",
c->name, c->hostname);
- } else if(errno == EINTR)
+ } else if(sockwouldblock(sockerrno))
return true;
else
- logger(LOG_ERR, _("Metadata socket read error for %s (%s): %s"),
- c->name, c->hostname, strerror(errno));
+ logger(LOG_ERR, "Metadata socket read error for %s (%s): %s",
+ c->name, c->hostname, sockstrerror(sockerrno));
return false;
}
c->buflen += lenin;
while(lenin > 0) {
+ reqlen = 0;
+
+ /* Is it proxy metadata? */
+
+ if(c->allow_request == PROXY) {
+ reqlen = receive_proxy_meta(c, oldlen, lenin);
+ if(reqlen < 0)
+ return false;
+ goto consume;
+ }
+
/* Decrypt */
if(c->status.decryptin && !decrypted) {
- result = EVP_DecryptUpdate(c->inctx, inbuf, &lenout, c->buffer + oldlen, lenin);
+ /* Check decryption limits */
+ if(lenin > c->inbudget) {
+ ifdebug(META) logger(LOG_ERR, "Byte limit exceeded for decryption from %s (%s)", c->name, c->hostname);
+ return false;
+ } else {
+ c->inbudget -= lenin;
+ }
+
+ result = EVP_DecryptUpdate(c->inctx, (unsigned char *)inbuf, &lenout, (unsigned char *)c->buffer + oldlen, lenin);
if(!result || lenout != lenin) {
- logger(LOG_ERR, _("Error while decrypting metadata from %s (%s): %s"),
+ logger(LOG_ERR, "Error while decrypting metadata from %s (%s): %s",
c->name, c->hostname, ERR_error_string(ERR_get_error(), NULL));
return false;
}
if(c->tcplen) {
if(c->tcplen <= c->buflen) {
- receive_tcppacket(c, c->buffer, c->tcplen);
+ if(c->allow_request != ALL) {
+ logger(LOG_ERR, "Got unauthorized TCP packet from %s (%s)", c->name, c->hostname);
+ return false;
+ }
- c->buflen -= c->tcplen;
- lenin -= c->tcplen - oldlen;
- memmove(c->buffer, c->buffer + c->tcplen, c->buflen);
- oldlen = 0;
+ receive_tcppacket(c, c->buffer, c->tcplen);
+ reqlen = c->tcplen;
c->tcplen = 0;
- continue;
- } else {
- break;
}
- }
-
- /* Otherwise we are waiting for a request */
-
- reqlen = 0;
-
- for(i = oldlen; i < c->buflen; i++) {
- if(c->buffer[i] == '\n') {
- c->buffer[i] = '\0'; /* replace end-of-line by end-of-string so we can use sscanf */
- reqlen = i + 1;
- break;
+ } else {
+ /* Otherwise we are waiting for a request */
+
+ for(i = oldlen; i < c->buflen; i++) {
+ if(c->buffer[i] == '\n') {
+ c->buffer[i] = '\0'; /* replace end-of-line by end-of-string so we can use sscanf */
+ c->reqlen = reqlen = i + 1;
+ break;
+ }
}
- }
- if(reqlen) {
- c->reqlen = reqlen;
- if(!receive_request(c))
+ if(reqlen && !receive_request(c))
return false;
+ }
+consume:
+ if(reqlen) {
c->buflen -= reqlen;
lenin -= reqlen - oldlen;
memmove(c->buffer, c->buffer + reqlen, c->buflen);
}
if(c->buflen >= MAXBUFSIZE) {
- logger(LOG_ERR, _("Metadata read buffer overflow for %s (%s)"),
+ logger(LOG_ERR, "Metadata read buffer overflow for %s (%s)",
c->name, c->hostname);
return false;
}
- c->last_ping_time = now;
-
return true;
}
projects / tinc / blobdiff