/*
protocol_misc.c -- handle the meta-protocol, miscellaneous functions
- Copyright (C) 1999-2002 Ivo Timmermans <ivo@o2w.nl>,
- 2000-2002 Guus Sliepen <guus@sliepen.eu.org>
+ Copyright (C) 1999-2005 Ivo Timmermans,
+ 2000-2013 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
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: protocol_misc.c,v 1.1.4.4 2002/06/21 10:11:19 guus Exp $
+ 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 "config.h"
-
-#include <stdlib.h>
-#include <string.h>
-#include <syslog.h>
-#include <stdio.h>
-#include <stdarg.h>
-#include <errno.h>
-
-#include <utils.h>
+#include "system.h"
#include "conf.h"
+#include "connection.h"
+#include "logger.h"
+#include "meta.h"
#include "net.h"
#include "netutl.h"
#include "protocol.h"
-#include "meta.h"
-#include "connection.h"
+#include "utils.h"
+#include "xalloc.h"
-#include "system.h"
+#ifndef MIN
+#define MIN(x, y) (((x)<(y))?(x):(y))
+#endif
+
+int maxoutbufsize = 0;
+int mtu_info_interval = 5;
+int udp_info_interval = 5;
/* Status and error notification routines */
-int send_status(connection_t *c, int statusno, char *statusstring)
-{
-cp
- if(!statusstring)
- statusstring = status_text[statusno];
-cp
- return send_request(c, "%d %d %s", STATUS, statusno, statusstring);
-}
-
-int status_h(connection_t *c)
-{
- int statusno;
- char statusstring[MAX_STRING_SIZE];
-cp
- if(sscanf(c->buffer, "%*d %d "MAX_STRING, &statusno, statusstring) != 2)
- {
- syslog(LOG_ERR, _("Got bad %s from %s (%s)"), "STATUS",
- c->name, c->hostname);
- return -1;
- }
-
- if(debug_lvl >= DEBUG_STATUS)
- {
- syslog(LOG_NOTICE, _("Status message from %s (%s): %s: %s"),
- c->name, c->hostname, status_text[statusno], statusstring);
- }
-
-cp
- return 0;
-}
-
-int send_error(connection_t *c, int err, char *errstring)
-{
-cp
- if(!errstring)
- errstring = strerror(err);
- return send_request(c, "%d %d %s", ERROR, err, errstring);
-}
-
-int error_h(connection_t *c)
-{
- int err;
- char errorstring[MAX_STRING_SIZE];
-cp
- if(sscanf(c->buffer, "%*d %d "MAX_STRING, &err, errorstring) != 2)
- {
- syslog(LOG_ERR, _("Got bad %s from %s (%s)"), "ERROR",
- c->name, c->hostname);
- return -1;
- }
-
- if(debug_lvl >= DEBUG_ERROR)
- {
- syslog(LOG_NOTICE, _("Error message from %s (%s): %s: %s"),
- c->name, c->hostname, strerror(err), errorstring);
- }
-
- terminate_connection(c, c->status.active);
-cp
- return 0;
-}
-
-int send_termreq(connection_t *c)
-{
-cp
- return send_request(c, "%d", TERMREQ);
-}
-
-int termreq_h(connection_t *c)
-{
-cp
- terminate_connection(c, c->status.active);
-cp
- return 0;
-}
-
-int send_ping(connection_t *c)
-{
-cp
- c->status.pinged = 1;
- c->last_ping_time = now;
-cp
- return send_request(c, "%d", PING);
-}
-
-int ping_h(connection_t *c)
-{
-cp
- return send_pong(c);
-}
-
-int send_pong(connection_t *c)
-{
-cp
- return send_request(c, "%d", PONG);
-}
-
-int pong_h(connection_t *c)
-{
-cp
- c->status.pinged = 0;
-
- /* Succesful connection, reset timeout if this is an outgoing connection. */
-
- if(c->outgoing)
- c->outgoing->timeout = 0;
-cp
- return 0;
+bool send_status(connection_t *c, int statusno, const char *statusstring) {
+ if(!statusstring)
+ statusstring = "Status";
+
+ return send_request(c, "%d %d %s", STATUS, statusno, statusstring);
+}
+
+bool status_h(connection_t *c, const char *request) {
+ int statusno;
+ char statusstring[MAX_STRING_SIZE];
+
+ if(sscanf(request, "%*d %d " MAX_STRING, &statusno, statusstring) != 2) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Got bad %s from %s (%s)", "STATUS",
+ c->name, c->hostname);
+ return false;
+ }
+
+ logger(DEBUG_STATUS, LOG_NOTICE, "Status message from %s (%s): %d: %s",
+ c->name, c->hostname, statusno, statusstring);
+
+ return true;
+}
+
+bool send_error(connection_t *c, int err, const char *errstring) {
+ if(!errstring)
+ errstring = "Error";
+
+ return send_request(c, "%d %d %s", ERROR, err, errstring);
+}
+
+bool error_h(connection_t *c, const char *request) {
+ int err;
+ char errorstring[MAX_STRING_SIZE];
+
+ if(sscanf(request, "%*d %d " MAX_STRING, &err, errorstring) != 2) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Got bad %s from %s (%s)", "ERROR",
+ c->name, c->hostname);
+ return false;
+ }
+
+ logger(DEBUG_ERROR, LOG_NOTICE, "Error message from %s (%s): %d: %s",
+ c->name, c->hostname, err, errorstring);
+
+ return false;
+}
+
+bool send_termreq(connection_t *c) {
+ return send_request(c, "%d", TERMREQ);
+}
+
+bool termreq_h(connection_t *c, const char *request) {
+ return false;
+}
+
+bool send_ping(connection_t *c) {
+ c->status.pinged = true;
+ c->last_ping_time = now.tv_sec;
+
+ return send_request(c, "%d", PING);
+}
+
+bool ping_h(connection_t *c, const char *request) {
+ return send_pong(c);
+}
+
+bool send_pong(connection_t *c) {
+ return send_request(c, "%d", PONG);
+}
+
+bool pong_h(connection_t *c, const char *request) {
+ c->status.pinged = false;
+
+ /* Succesful connection, reset timeout if this is an outgoing connection. */
+
+ if(c->outgoing) {
+ c->outgoing->timeout = 0;
+ c->outgoing->cfg = NULL;
+ if(c->outgoing->ai)
+ freeaddrinfo(c->outgoing->ai);
+ c->outgoing->ai = NULL;
+ c->outgoing->aip = NULL;
+ }
+
+ return true;
}
/* Sending and receiving packets via TCP */
-int send_tcppacket(connection_t *c, vpn_packet_t *packet)
-{
- int x;
-cp
- /* Evil hack. */
+bool send_tcppacket(connection_t *c, const vpn_packet_t *packet) {
+ /* If there already is a lot of data in the outbuf buffer, discard this packet.
+ We use a very simple Random Early Drop algorithm. */
+
+ if(2.0 * c->outbuf.len / (float)maxoutbufsize - 1 > (float)rand()/(float)RAND_MAX)
+ return true;
- x = send_request(c, "%d %hd", PACKET, packet->len);
+ if(!send_request(c, "%d %hd", PACKET, packet->len))
+ return false;
- if(x)
- return x;
-cp
- return send_meta(c, packet->data, packet->len);
+ return send_meta(c, (char *)DATA(packet), packet->len);
}
-int tcppacket_h(connection_t *c)
-{
- short int len;
-cp
- if(sscanf(c->buffer, "%*d %hd", &len) != 1)
- {
- syslog(LOG_ERR, _("Got bad %s from %s (%s)"), "PACKET", c->name, c->hostname);
- return -1;
- }
+bool tcppacket_h(connection_t *c, const char *request) {
+ short int len;
- /* Set reqlen to len, this will tell receive_meta() that a tcppacket is coming. */
+ if(sscanf(request, "%*d %hd", &len) != 1) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Got bad %s from %s (%s)", "PACKET", c->name,
+ c->hostname);
+ return false;
+ }
- c->tcplen = len;
-cp
- return 0;
+ /* Set reqlen to len, this will tell receive_meta() that a tcppacket is coming. */
+
+ c->tcplen = len;
+
+ return true;
}
-/* Status strings */
+bool send_sptps_tcppacket(connection_t *c, const char* packet, int len) {
+ /* If there already is a lot of data in the outbuf buffer, discard this packet.
+ We use a very simple Random Early Drop algorithm. */
+
+ if(2.0 * c->outbuf.len / (float)maxoutbufsize - 1 > (float)rand()/(float)RAND_MAX)
+ return true;
+
+ if(!send_request(c, "%d %d", SPTPS_PACKET, len))
+ return false;
+
+ send_meta_raw(c, packet, len);
+ return true;
+}
+
+bool sptps_tcppacket_h(connection_t *c, const char* request) {
+ short int len;
+
+ if(sscanf(request, "%*d %hd", &len) != 1) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Got bad %s from %s (%s)", "SPTPS_PACKET", c->name,
+ c->hostname);
+ return false;
+ }
+
+ /* Set sptpslen to len, this will tell receive_meta() that a SPTPS packet is coming. */
+
+ c->sptpslen = len;
+
+ return true;
+}
+
+/* Transmitting UDP information */
+
+bool send_udp_info(node_t *from, node_t *to) {
+ /* If there's a static relay in the path, there's no point in sending the message
+ farther than the static relay. */
+ to = (to->via == myself) ? to->nexthop : to->via;
+
+ /* Skip cases where sending UDP info messages doesn't make sense.
+ This is done here in order to avoid repeating the same logic in multiple callsites. */
+
+ if(to == myself)
+ return true;
+
+ if(!to->status.reachable)
+ return true;
+
+ if(from == myself) {
+ if(to->connection)
+ return true;
+
+ struct timeval elapsed;
+ timersub(&now, &to->udp_info_sent, &elapsed);
+ if(elapsed.tv_sec < udp_info_interval)
+ return true;
+ }
+
+ if((myself->options | from->options | to->options) & OPTION_TCPONLY)
+ return true;
+
+ if((to->nexthop->options >> 24) < 5)
+ return true;
-char (*status_text[]) = {
- "Warning",
-};
+ char *from_address, *from_port;
+ /* If we're the originator, the address we use is irrelevant
+ because the first intermediate node will ignore it.
+ We use our local address as it somewhat makes sense
+ and it's simpler than introducing an encoding for "null" addresses anyway. */
+ sockaddr2str((from != myself) ? &from->address : &to->nexthop->connection->edge->local_address, &from_address, &from_port);
-/* Error strings */
+ bool x = send_request(to->nexthop->connection, "%d %s %s %s %s", UDP_INFO, from->name, to->name, from_address, from_port);
-char (*error_text[]) = {
- "Error",
-};
+ free(from_address);
+ free(from_port);
+
+ if(from == myself)
+ to->udp_info_sent = now;
+
+ return x;
+}
+
+bool udp_info_h(connection_t *c, const char* request) {
+ char from_name[MAX_STRING_SIZE];
+ char to_name[MAX_STRING_SIZE];
+ char from_address[MAX_STRING_SIZE];
+ char from_port[MAX_STRING_SIZE];
+
+ if(sscanf(request, "%*d "MAX_STRING" "MAX_STRING" "MAX_STRING" "MAX_STRING, from_name, to_name, from_address, from_port) != 4) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Got bad %s from %s (%s)", "UDP_INFO", c->name, c->hostname);
+ return false;
+ }
+
+ if(!check_id(from_name) || !check_id(to_name)) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Got bad %s from %s (%s): %s", "UDP_INFO", c->name, c->hostname, "invalid name");
+ return false;
+ }
+
+ node_t *from = lookup_node(from_name);
+ if(!from) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Got %s from %s (%s) origin %s which does not exist in our connection list", "UDP_INFO", c->name, c->hostname, from_name);
+ return true;
+ }
+
+ if(from != from->via) {
+ /* Not supposed to happen, as it means the message wandered past a static relay */
+ logger(DEBUG_PROTOCOL, LOG_WARNING, "Got UDP info message from %s (%s) which we can't reach directly", from->name, from->hostname);
+ return true;
+ }
+
+ /* If we have a direct edge to "from", we are in a better position
+ to guess its address than it is itself. */
+ if(!from->connection && !from->status.udp_confirmed) {
+ sockaddr_t from_addr = str2sockaddr(from_address, from_port);
+ if(sockaddrcmp(&from_addr, &from->address))
+ update_node_udp(from, &from_addr);
+ }
+
+ node_t *to = lookup_node(to_name);
+ if(!to) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Got %s from %s (%s) destination %s which does not exist in our connection list", "UDP_INFO", c->name, c->hostname, to_name);
+ return true;
+ }
+
+ /* Send our own data (which could be what we just received) up the chain. */
+
+ return send_udp_info(from, to);
+}
+
+/* Transmitting MTU information */
+
+bool send_mtu_info(node_t *from, node_t *to, int mtu) {
+ /* Skip cases where sending MTU info messages doesn't make sense.
+ This is done here in order to avoid repeating the same logic in multiple callsites. */
+
+ if(to == myself)
+ return true;
+
+ if(!to->status.reachable)
+ return true;
+
+ if(from == myself) {
+ if(to->connection)
+ return true;
+
+ struct timeval elapsed;
+ timersub(&now, &to->mtu_info_sent, &elapsed);
+ if(elapsed.tv_sec < mtu_info_interval)
+ return true;
+ }
+
+ if((to->nexthop->options >> 24) < 6)
+ return true;
+
+ /* We will send the passed-in MTU value, unless we believe ours is better. */
+
+ node_t *via = (from->via == myself) ? from->nexthop : from->via;
+ if(from->minmtu == from->maxmtu && from->via == myself) {
+ /* We have a direct measurement. Override the value entirely.
+ Note that we only do that if we are sitting as a static relay in the path;
+ otherwise, we can't guarantee packets will flow through us, and increasing
+ MTU could therefore end up being too optimistic. */
+ mtu = from->minmtu;
+ } else if(via->minmtu == via->maxmtu) {
+ /* Static relay. Ensure packets will make it through the entire relay path. */
+ mtu = MIN(mtu, via->minmtu);
+ } else if(via->nexthop->minmtu == via->nexthop->maxmtu) {
+ /* Dynamic relay. Ensure packets will make it through the entire relay path. */
+ mtu = MIN(mtu, via->nexthop->minmtu);
+ }
+
+ if(from == myself)
+ to->mtu_info_sent = now;
+
+ /* If none of the conditions above match in the steady state, it means we're using TCP,
+ so the MTU is irrelevant. That said, it is still important to honor the MTU that was passed in,
+ because other parts of the relay path might be able to use UDP, which means they care about the MTU. */
+
+ return send_request(to->nexthop->connection, "%d %s %s %d", MTU_INFO, from->name, to->name, mtu);
+}
+
+bool mtu_info_h(connection_t *c, const char* request) {
+ char from_name[MAX_STRING_SIZE];
+ char to_name[MAX_STRING_SIZE];
+ int mtu;
+
+ if(sscanf(request, "%*d "MAX_STRING" "MAX_STRING" %d", from_name, to_name, &mtu) != 3) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Got bad %s from %s (%s)", "MTU_INFO", c->name, c->hostname);
+ return false;
+ }
+
+ if(mtu < 512) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Got bad %s from %s (%s): %s", "MTU_INFO", c->name, c->hostname, "invalid MTU");
+ return false;
+ }
+
+ mtu = MIN(mtu, MTU);
+
+ if(!check_id(from_name) || !check_id(to_name)) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Got bad %s from %s (%s): %s", "MTU_INFO", c->name, c->hostname, "invalid name");
+ return false;
+ }
+
+ node_t *from = lookup_node(from_name);
+ if(!from) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Got %s from %s (%s) origin %s which does not exist in our connection list", "MTU_INFO", c->name, c->hostname, from_name);
+ return true;
+ }
+
+ /* If we don't know the current MTU for that node, use the one we received.
+ Even if we're about to make our own measurements, the value we got from downstream nodes should be pretty close
+ so it's a good idea to use it in the mean time. */
+ if(from->mtu != mtu && from->minmtu != from->maxmtu) {
+ logger(DEBUG_TRAFFIC, LOG_INFO, "Using provisional MTU %d for node %s (%s)", mtu, from->name, from->hostname);
+ from->mtu = mtu;
+ }
+
+ node_t *to = lookup_node(to_name);
+ if(!to) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Got %s from %s (%s) destination %s which does not exist in our connection list", "MTU_INFO", c->name, c->hostname, to_name);
+ return true;
+ }
+
+ /* Continue passing the MTU value (or a better one if we have it) up the chain. */
+
+ return send_mtu_info(from, to, mtu);
+}
projects / tinc / blobdiff