/*
net_packet.c -- Handles in- and outgoing VPN packets
- Copyright (C) 1998-2003 Ivo Timmermans <ivo@o2w.nl>,
- 2000-2003 Guus Sliepen <guus@sliepen.eu.org>
+ Copyright (C) 1998-2005 Ivo Timmermans,
+ 2000-2012 Guus Sliepen <guus@tinc-vpn.org>
+ 2010 Timothy Redaelli <timothy@redaelli.eu>
+ 2010 Brandon Black <blblack@gmail.com>
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: net_packet.c,v 1.1.2.49 2003/12/27 16:32:52 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 "system.h"
#include <openssl/pem.h>
#include <openssl/hmac.h>
+#ifdef HAVE_ZLIB
#include <zlib.h>
-#include <lzo1x.h>
+#endif
+
+#ifdef HAVE_LZO
+#include LZO1X_H
+#endif
-#include "avl_tree.h"
+#include "cipher.h"
#include "conf.h"
#include "connection.h"
+#include "crypto.h"
+#include "digest.h"
#include "device.h"
#include "ethernet.h"
-#include "event.h"
#include "graph.h"
-#include "list.h"
#include "logger.h"
#include "net.h"
#include "netutl.h"
#include "utils.h"
#include "xalloc.h"
-#ifdef WSAEMSGSIZE
-#define EMSGSIZE WSAEMSGSIZE
-#endif
-
int keylifetime = 0;
-int keyexpires = 0;
-EVP_CIPHER_CTX packet_ctx;
+#ifdef HAVE_LZO
static char lzo_wrkmem[LZO1X_999_MEM_COMPRESS > LZO1X_1_MEM_COMPRESS ? LZO1X_999_MEM_COMPRESS : LZO1X_1_MEM_COMPRESS];
+#endif
static void send_udppacket(node_t *, vpn_packet_t *);
+unsigned replaywin = 16;
+bool localdiscovery = false;
+
#define MAX_SEQNO 1073741824
-void send_mtu_probe(node_t *n)
-{
- vpn_packet_t packet;
- int len, i;
-
- cp();
+/* mtuprobes == 1..30: initial discovery, send bursts with 1 second interval
+ mtuprobes == 31: sleep pinginterval seconds
+ mtuprobes == 32: send 1 burst, sleep pingtimeout second
+ mtuprobes == 33: no response from other side, restart PMTU discovery process
+
+ Probes are sent in batches of three, with random sizes between the lower and
+ upper boundaries for the MTU thus far discovered.
+ In case local discovery is enabled, a fourth packet is added to each batch,
+ which will be broadcast to the local network.
+*/
+
+static void send_mtu_probe_handler(int fd, short events, void *data) {
+ node_t *n = data;
+ int timeout = 1;
+
n->mtuprobes++;
- n->mtuevent = NULL;
- if(n->mtuprobes >= 10 && !n->minmtu) {
- ifdebug(TRAFFIC) logger(LOG_INFO, _("No response to MTU probes from %s (%s)"), n->name, n->hostname);
+ if(!n->status.reachable || !n->status.validkey) {
+ logger(DEBUG_TRAFFIC, LOG_INFO, "Trying to send MTU probe to unreachable or rekeying node %s (%s)", n->name, n->hostname);
+ n->mtuprobes = 0;
return;
}
- for(i = 0; i < 3; i++) {
- if(n->mtuprobes >= 30 || n->minmtu >= n->maxmtu) {
- n->mtu = n->minmtu;
- ifdebug(TRAFFIC) logger(LOG_INFO, _("Fixing MTU of %s (%s) to %d after %d probes"), n->name, n->hostname, n->mtu, n->mtuprobes);
- return;
+ if(n->mtuprobes > 32) {
+ if(!n->minmtu) {
+ n->mtuprobes = 31;
+ timeout = pinginterval;
+ goto end;
}
- len = n->minmtu + 1 + random() % (n->maxmtu - n->minmtu);
+ logger(DEBUG_TRAFFIC, LOG_INFO, "%s (%s) did not respond to UDP ping, restarting PMTU discovery", n->name, n->hostname);
+ n->mtuprobes = 1;
+ n->minmtu = 0;
+ n->maxmtu = MTU;
+ }
+
+ if(n->mtuprobes >= 10 && n->mtuprobes < 32 && !n->minmtu) {
+ logger(DEBUG_TRAFFIC, LOG_INFO, "No response to MTU probes from %s (%s)", n->name, n->hostname);
+ n->mtuprobes = 31;
+ }
+
+ if(n->mtuprobes == 30 || (n->mtuprobes < 30 && n->minmtu >= n->maxmtu)) {
+ if(n->minmtu > n->maxmtu)
+ n->minmtu = n->maxmtu;
+ else
+ n->maxmtu = n->minmtu;
+ n->mtu = n->minmtu;
+ logger(DEBUG_TRAFFIC, LOG_INFO, "Fixing MTU of %s (%s) to %d after %d probes", n->name, n->hostname, n->mtu, n->mtuprobes);
+ n->mtuprobes = 31;
+ }
+
+ if(n->mtuprobes == 31) {
+ timeout = pinginterval;
+ goto end;
+ } else if(n->mtuprobes == 32) {
+ timeout = pingtimeout;
+ }
+
+ for(int i = 0; i < 3 + localdiscovery; i++) {
+ int len;
+
+ if(n->maxmtu <= n->minmtu)
+ len = n->maxmtu;
+ else
+ len = n->minmtu + 1 + rand() % (n->maxmtu - n->minmtu);
+
if(len < 64)
len = 64;
+ vpn_packet_t packet;
memset(packet.data, 0, 14);
- RAND_pseudo_bytes(packet.data + 14, len - 14);
+ randomize(packet.data + 14, len - 14);
packet.len = len;
+ if(i >= 3 && n->mtuprobes <= 10)
+ packet.priority = -1;
+ else
+ packet.priority = 0;
- ifdebug(TRAFFIC) logger(LOG_INFO, _("Sending MTU probe length %d to %s (%s)"), len, n->name, n->hostname);
+ logger(DEBUG_TRAFFIC, LOG_INFO, "Sending MTU probe length %d to %s (%s)", len, n->name, n->hostname);
send_udppacket(n, &packet);
}
- n->mtuevent = xmalloc(sizeof(*n->mtuevent));
- n->mtuevent->handler = (event_handler_t)send_mtu_probe;
- n->mtuevent->data = n;
- n->mtuevent->time = now + 1;
- event_add(n->mtuevent);
+end:
+ event_add(&n->mtuevent, &(struct timeval){timeout, 0});
}
-void mtu_probe_h(node_t *n, vpn_packet_t *packet) {
- ifdebug(TRAFFIC) logger(LOG_INFO, _("Got MTU probe length %d from %s (%s)"), packet->len, n->name, n->hostname);
+void send_mtu_probe(node_t *n) {
+ if(!timeout_initialized(&n->mtuevent))
+ timeout_set(&n->mtuevent, send_mtu_probe_handler, n);
+ send_mtu_probe_handler(0, 0, n);
+}
+
+static void mtu_probe_h(node_t *n, vpn_packet_t *packet, length_t len) {
+ logger(DEBUG_TRAFFIC, LOG_INFO, "Got MTU probe length %d from %s (%s)", packet->len, n->name, n->hostname);
if(!packet->data[0]) {
packet->data[0] = 1;
- send_packet(n, packet);
+ send_udppacket(n, packet);
} else {
- if(n->minmtu < packet->len)
- n->minmtu = packet->len;
+ if(n->mtuprobes > 30) {
+ if(n->minmtu)
+ n->mtuprobes = 30;
+ else
+ n->mtuprobes = 1;
+ }
+
+ if(len > n->maxmtu)
+ len = n->maxmtu;
+ if(n->minmtu < len)
+ n->minmtu = len;
}
}
-static length_t compress_packet(uint8_t *dest, const uint8_t *source, length_t len, int level)
-{
- if(level == 10) {
+static length_t compress_packet(uint8_t *dest, const uint8_t *source, length_t len, int level) {
+ if(level == 0) {
+ memcpy(dest, source, len);
+ return len;
+ } else if(level == 10) {
+#ifdef HAVE_LZO
lzo_uint lzolen = MAXSIZE;
lzo1x_1_compress(source, len, dest, &lzolen, lzo_wrkmem);
return lzolen;
+#else
+ return -1;
+#endif
} else if(level < 10) {
+#ifdef HAVE_ZLIB
unsigned long destlen = MAXSIZE;
if(compress2(dest, &destlen, source, len, level) == Z_OK)
return destlen;
else
+#endif
return -1;
} else {
+#ifdef HAVE_LZO
lzo_uint lzolen = MAXSIZE;
lzo1x_999_compress(source, len, dest, &lzolen, lzo_wrkmem);
return lzolen;
+#else
+ return -1;
+#endif
}
return -1;
}
-static length_t uncompress_packet(uint8_t *dest, const uint8_t *source, length_t len, int level)
-{
- if(level > 9) {
+static length_t uncompress_packet(uint8_t *dest, const uint8_t *source, length_t len, int level) {
+ if(level == 0) {
+ memcpy(dest, source, len);
+ return len;
+ } else if(level > 9) {
+#ifdef HAVE_LZO
lzo_uint lzolen = MAXSIZE;
if(lzo1x_decompress_safe(source, len, dest, &lzolen, NULL) == LZO_E_OK)
return lzolen;
else
+#endif
return -1;
- } else {
+ }
+#ifdef HAVE_ZLIB
+ else {
unsigned long destlen = MAXSIZE;
if(uncompress(dest, &destlen, source, len) == Z_OK)
return destlen;
else
return -1;
}
-
+#endif
+
return -1;
}
/* VPN packet I/O */
-static void receive_packet(node_t *n, vpn_packet_t *packet)
-{
- cp();
-
- ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Received packet of %d bytes from %s (%s)"),
+static void receive_packet(node_t *n, vpn_packet_t *packet) {
+ logger(DEBUG_TRAFFIC, LOG_DEBUG, "Received packet of %d bytes from %s (%s)",
packet->len, n->name, n->hostname);
+ n->in_packets++;
+ n->in_bytes += packet->len;
+
route(n, packet);
}
-static void receive_udppacket(node_t *n, vpn_packet_t *inpkt)
-{
+static bool try_mac(node_t *n, const vpn_packet_t *inpkt) {
+ if(n->status.sptps)
+ return sptps_verify_datagram(&n->sptps, (char *)&inpkt->seqno, inpkt->len);
+
+ if(!digest_active(&n->indigest) || inpkt->len < sizeof inpkt->seqno + digest_length(&n->indigest))
+ return false;
+
+ return digest_verify(&n->indigest, &inpkt->seqno, inpkt->len - n->indigest.maclength, (const char *)&inpkt->seqno + inpkt->len - n->indigest.maclength);
+}
+
+static void receive_udppacket(node_t *n, vpn_packet_t *inpkt) {
vpn_packet_t pkt1, pkt2;
vpn_packet_t *pkt[] = { &pkt1, &pkt2, &pkt1, &pkt2 };
int nextpkt = 0;
vpn_packet_t *outpkt = pkt[0];
- int outlen, outpad;
- char hmac[EVP_MAX_MD_SIZE];
- int i;
+ size_t outlen;
- cp();
+ if(n->status.sptps) {
+ sptps_receive_data(&n->sptps, (char *)&inpkt->seqno, inpkt->len);
+ return;
+ }
+
+ if(!cipher_active(&n->incipher)) {
+ logger(DEBUG_TRAFFIC, LOG_DEBUG, "Got packet from %s (%s) but he hasn't got our key yet",
+ n->name, n->hostname);
+ return;
+ }
/* Check packet length */
- if(inpkt->len < sizeof(inpkt->seqno) + myself->maclength) {
- ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Got too short packet from %s (%s)"),
+ if(inpkt->len < sizeof inpkt->seqno + digest_length(&n->indigest)) {
+ logger(DEBUG_TRAFFIC, LOG_DEBUG, "Got too short packet from %s (%s)",
n->name, n->hostname);
return;
}
/* Check the message authentication code */
- if(myself->digest && myself->maclength) {
- inpkt->len -= myself->maclength;
- HMAC(myself->digest, myself->key, myself->keylength,
- (char *) &inpkt->seqno, inpkt->len, hmac, NULL);
-
- if(memcmp(hmac, (char *) &inpkt->seqno + inpkt->len, myself->maclength)) {
- ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Got unauthenticated packet from %s (%s)"),
- n->name, n->hostname);
+ if(digest_active(&n->indigest)) {
+ inpkt->len -= n->indigest.maclength;
+ if(!digest_verify(&n->indigest, &inpkt->seqno, inpkt->len, (const char *)&inpkt->seqno + inpkt->len)) {
+ logger(DEBUG_TRAFFIC, LOG_DEBUG, "Got unauthenticated packet from %s (%s)", n->name, n->hostname);
return;
}
}
-
/* Decrypt the packet */
- if(myself->cipher) {
+ if(cipher_active(&n->incipher)) {
outpkt = pkt[nextpkt++];
+ outlen = MAXSIZE;
- if(!EVP_DecryptInit_ex(&packet_ctx, NULL, NULL, NULL, NULL)
- || !EVP_DecryptUpdate(&packet_ctx, (char *) &outpkt->seqno, &outlen,
- (char *) &inpkt->seqno, inpkt->len)
- || !EVP_DecryptFinal_ex(&packet_ctx, (char *) &outpkt->seqno + outlen, &outpad)) {
- ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Error decrypting packet from %s (%s): %s"),
- n->name, n->hostname, ERR_error_string(ERR_get_error(), NULL));
+ if(!cipher_decrypt(&n->incipher, &inpkt->seqno, inpkt->len, &outpkt->seqno, &outlen, true)) {
+ logger(DEBUG_TRAFFIC, LOG_DEBUG, "Error decrypting packet from %s (%s)", n->name, n->hostname);
return;
}
- outpkt->len = outlen + outpad;
+ outpkt->len = outlen;
inpkt = outpkt;
}
/* Check the sequence number */
- inpkt->len -= sizeof(inpkt->seqno);
+ inpkt->len -= sizeof inpkt->seqno;
inpkt->seqno = ntohl(inpkt->seqno);
- if(inpkt->seqno != n->received_seqno + 1) {
- if(inpkt->seqno >= n->received_seqno + sizeof(n->late) * 8) {
- logger(LOG_WARNING, _("Lost %d packets from %s (%s)"),
- inpkt->seqno - n->received_seqno - 1, n->name, n->hostname);
-
- memset(n->late, 0, sizeof(n->late));
- } else if (inpkt->seqno <= n->received_seqno) {
- if(inpkt->seqno <= n->received_seqno - sizeof(n->late) * 8 || !(n->late[(inpkt->seqno / 8) % sizeof(n->late)] & (1 << inpkt->seqno % 8))) {
- logger(LOG_WARNING, _("Got late or replayed packet from %s (%s), seqno %d, last received %d"),
- n->name, n->hostname, inpkt->seqno, n->received_seqno);
- } else
- for(i = n->received_seqno + 1; i < inpkt->seqno; i++)
- n->late[(inpkt->seqno / 8) % sizeof(n->late)] |= 1 << i % 8;
+ if(replaywin) {
+ if(inpkt->seqno != n->received_seqno + 1) {
+ if(inpkt->seqno >= n->received_seqno + replaywin * 8) {
+ if(n->farfuture++ < replaywin >> 2) {
+ logger(DEBUG_ALWAYS, LOG_WARNING, "Packet from %s (%s) is %d seqs in the future, dropped (%u)",
+ n->name, n->hostname, inpkt->seqno - n->received_seqno - 1, n->farfuture);
+ return;
+ }
+ logger(DEBUG_ALWAYS, LOG_WARNING, "Lost %d packets from %s (%s)",
+ inpkt->seqno - n->received_seqno - 1, n->name, n->hostname);
+ memset(n->late, 0, replaywin);
+ } else if (inpkt->seqno <= n->received_seqno) {
+ if((n->received_seqno >= replaywin * 8 && inpkt->seqno <= n->received_seqno - replaywin * 8) || !(n->late[(inpkt->seqno / 8) % replaywin] & (1 << inpkt->seqno % 8))) {
+ logger(DEBUG_ALWAYS, LOG_WARNING, "Got late or replayed packet from %s (%s), seqno %d, last received %d",
+ n->name, n->hostname, inpkt->seqno, n->received_seqno);
+ return;
+ }
+ } else {
+ for(int i = n->received_seqno + 1; i < inpkt->seqno; i++)
+ n->late[(i / 8) % replaywin] |= 1 << i % 8;
+ }
}
+
+ n->farfuture = 0;
+ n->late[(inpkt->seqno / 8) % replaywin] &= ~(1 << inpkt->seqno % 8);
}
-
- n->received_seqno = inpkt->seqno;
- n->late[(n->received_seqno / 8) % sizeof(n->late)] &= ~(1 << n->received_seqno % 8);
+
+ if(inpkt->seqno > n->received_seqno)
+ n->received_seqno = inpkt->seqno;
if(n->received_seqno > MAX_SEQNO)
- keyexpires = 0;
+ regenerate_key();
/* Decompress the packet */
- if(myself->compression) {
+ length_t origlen = inpkt->len;
+
+ if(n->incompression) {
outpkt = pkt[nextpkt++];
- if((outpkt->len = uncompress_packet(outpkt->data, inpkt->data, inpkt->len, myself->compression)) < 0) {
- ifdebug(TRAFFIC) logger(LOG_ERR, _("Error while uncompressing packet from %s (%s)"),
+ if((outpkt->len = uncompress_packet(outpkt->data, inpkt->data, inpkt->len, n->incompression)) < 0) {
+ logger(DEBUG_TRAFFIC, LOG_ERR, "Error while uncompressing packet from %s (%s)",
n->name, n->hostname);
return;
}
inpkt = outpkt;
+
+ origlen -= MTU/64 + 20;
}
- if(n->connection)
- n->connection->last_ping_time = now;
+ inpkt->priority = 0;
if(!inpkt->data[12] && !inpkt->data[13])
- mtu_probe_h(n, inpkt);
+ mtu_probe_h(n, inpkt, origlen);
else
receive_packet(n, inpkt);
}
-void receive_tcppacket(connection_t *c, char *buffer, int len)
-{
+void receive_tcppacket(connection_t *c, const char *buffer, int len) {
vpn_packet_t outpkt;
- cp();
-
outpkt.len = len;
+ if(c->options & OPTION_TCPONLY)
+ outpkt.priority = 0;
+ else
+ outpkt.priority = -1;
memcpy(outpkt.data, buffer, len);
receive_packet(c->node, &outpkt);
}
-static void send_udppacket(node_t *n, vpn_packet_t *inpkt)
-{
+static void send_sptps_packet(node_t *n, vpn_packet_t *origpkt) {
+ if(!n->status.validkey) {
+ logger(DEBUG_TRAFFIC, LOG_INFO, "No valid key known yet for %s (%s)", n->name, n->hostname);
+ if(!n->status.waitingforkey)
+ send_req_key(n);
+ else if(n->last_req_key + 10 < time(NULL)) {
+ sptps_stop(&n->sptps);
+ n->status.waitingforkey = false;
+ send_req_key(n);
+ }
+ return;
+ }
+
+ uint8_t type = 0;
+ int offset = 0;
+
+ if(!(origpkt->data[12] | origpkt->data[13])) {
+ sptps_send_record(&n->sptps, PKT_PROBE, (char *)origpkt->data, origpkt->len);
+ return;
+ }
+
+ if(routing_mode == RMODE_ROUTER)
+ offset = 14;
+ else
+ type = PKT_MAC;
+
+ if(origpkt->len < offset)
+ return;
+
+ vpn_packet_t outpkt;
+
+ if(n->outcompression) {
+ int len = compress_packet(outpkt.data + offset, origpkt->data + offset, origpkt->len - offset, n->outcompression);
+ if(len < 0) {
+ logger(DEBUG_TRAFFIC, LOG_ERR, "Error while compressing packet to %s (%s)", n->name, n->hostname);
+ } else if(len < origpkt->len - offset) {
+ outpkt.len = len + offset;
+ origpkt = &outpkt;
+ type |= PKT_COMPRESSED;
+ }
+ }
+
+ sptps_send_record(&n->sptps, type, (char *)origpkt->data + offset, origpkt->len - offset);
+ return;
+}
+
+static void send_udppacket(node_t *n, vpn_packet_t *origpkt) {
vpn_packet_t pkt1, pkt2;
vpn_packet_t *pkt[] = { &pkt1, &pkt2, &pkt1, &pkt2 };
+ vpn_packet_t *inpkt = origpkt;
int nextpkt = 0;
vpn_packet_t *outpkt;
- int origlen;
- int outlen, outpad;
- vpn_packet_t *copy;
+ int origlen = origpkt->len;
+ size_t outlen;
+#if defined(SOL_IP) && defined(IP_TOS)
static int priority = 0;
- int origpriority;
- int sock;
+#endif
+ int origpriority = origpkt->priority;
+
+ if(!n->status.reachable) {
+ logger(DEBUG_TRAFFIC, LOG_INFO, "Trying to send UDP packet to unreachable node %s (%s)", n->name, n->hostname);
+ return;
+ }
- cp();
+ if(n->status.sptps)
+ return send_sptps_packet(n, origpkt);
/* Make sure we have a valid key */
if(!n->status.validkey) {
- ifdebug(TRAFFIC) logger(LOG_INFO,
- _("No valid key known yet for %s (%s), queueing packet"),
- n->name, n->hostname);
+ time_t now = time(NULL);
- /* Since packet is on the stack of handle_tap_input(), we have to make a copy of it first. */
+ logger(DEBUG_TRAFFIC, LOG_INFO,
+ "No valid key known yet for %s (%s), forwarding via TCP",
+ n->name, n->hostname);
- *(copy = xmalloc(sizeof(*copy))) = *inpkt;
+ if(n->last_req_key + 10 <= now) {
+ send_req_key(n);
+ n->last_req_key = now;
+ }
- list_insert_tail(n->queue, copy);
+ send_tcppacket(n->nexthop->connection, origpkt);
- if(n->queue->count > MAXQUEUELENGTH)
- list_delete_head(n->queue);
+ return;
+ }
- if(!n->status.waitingforkey)
- send_req_key(n->nexthop->connection, myself, n);
+ if(n->options & OPTION_PMTU_DISCOVERY && inpkt->len > n->minmtu && (inpkt->data[12] | inpkt->data[13])) {
+ logger(DEBUG_TRAFFIC, LOG_INFO,
+ "Packet for %s (%s) larger than minimum MTU, forwarding via %s",
+ n->name, n->hostname, n != n->nexthop ? n->nexthop->name : "TCP");
- n->status.waitingforkey = true;
+ if(n != n->nexthop)
+ send_packet(n->nexthop, origpkt);
+ else
+ send_tcppacket(n->nexthop->connection, origpkt);
return;
}
- origlen = inpkt->len;
- origpriority = inpkt->priority;
-
/* Compress the packet */
- if(n->compression) {
+ if(n->outcompression) {
outpkt = pkt[nextpkt++];
- if((outpkt->len = compress_packet(outpkt->data, inpkt->data, inpkt->len, n->compression)) < 0) {
- ifdebug(TRAFFIC) logger(LOG_ERR, _("Error while compressing packet to %s (%s)"),
+ if((outpkt->len = compress_packet(outpkt->data, inpkt->data, inpkt->len, n->outcompression)) < 0) {
+ logger(DEBUG_TRAFFIC, LOG_ERR, "Error while compressing packet to %s (%s)",
n->name, n->hostname);
return;
}
/* Add sequence number */
inpkt->seqno = htonl(++(n->sent_seqno));
- inpkt->len += sizeof(inpkt->seqno);
+ inpkt->len += sizeof inpkt->seqno;
/* Encrypt the packet */
- if(n->cipher) {
+ if(cipher_active(&n->outcipher)) {
outpkt = pkt[nextpkt++];
+ outlen = MAXSIZE;
- if(!EVP_EncryptInit_ex(&n->packet_ctx, NULL, NULL, NULL, NULL)
- || !EVP_EncryptUpdate(&n->packet_ctx, (char *) &outpkt->seqno, &outlen,
- (char *) &inpkt->seqno, inpkt->len)
- || !EVP_EncryptFinal_ex(&n->packet_ctx, (char *) &outpkt->seqno + outlen, &outpad)) {
- ifdebug(TRAFFIC) logger(LOG_ERR, _("Error while encrypting packet to %s (%s): %s"),
- n->name, n->hostname, ERR_error_string(ERR_get_error(), NULL));
+ if(!cipher_encrypt(&n->outcipher, &inpkt->seqno, inpkt->len, &outpkt->seqno, &outlen, true)) {
+ logger(DEBUG_TRAFFIC, LOG_ERR, "Error while encrypting packet to %s (%s)", n->name, n->hostname);
goto end;
}
- outpkt->len = outlen + outpad;
+ outpkt->len = outlen;
inpkt = outpkt;
}
/* Add the message authentication code */
- if(n->digest && n->maclength) {
- HMAC(n->digest, n->key, n->keylength, (char *) &inpkt->seqno,
- inpkt->len, (char *) &inpkt->seqno + inpkt->len, &outlen);
- inpkt->len += n->maclength;
+ if(digest_active(&n->outdigest)) {
+ digest_create(&n->outdigest, &inpkt->seqno, inpkt->len, (char *)&inpkt->seqno + inpkt->len);
+ inpkt->len += digest_length(&n->outdigest);
}
/* Determine which socket we have to use */
- for(sock = 0; sock < listen_sockets; sock++)
- if(n->address.sa.sa_family == listen_socket[sock].sa.sa.sa_family)
- break;
-
- if(sock >= listen_sockets)
- sock = 0; /* If none is available, just use the first and hope for the best. */
+ if(n->address.sa.sa_family != listen_socket[n->sock].sa.sa.sa_family) {
+ for(int sock = 0; sock < listen_sockets; sock++) {
+ if(n->address.sa.sa_family == listen_socket[sock].sa.sa.sa_family) {
+ n->sock = sock;
+ break;
+ }
+ }
+ }
/* Send the packet */
+ struct sockaddr *sa;
+ socklen_t sl;
+ int sock;
+
+ /* Overloaded use of priority field: -1 means local broadcast */
+
+ if(origpriority == -1 && n->prevedge) {
+ struct sockaddr_in in;
+ in.sin_family = AF_INET;
+ in.sin_addr.s_addr = -1;
+ in.sin_port = n->prevedge->address.in.sin_port;
+ sa = (struct sockaddr *)∈
+ sl = sizeof in;
+ sock = 0;
+ } else {
+ if(origpriority == -1)
+ origpriority = 0;
+
+ sa = &(n->address.sa);
+ sl = SALEN(n->address.sa);
+ sock = n->sock;
+ }
+
#if defined(SOL_IP) && defined(IP_TOS)
if(priorityinheritance && origpriority != priority
- && listen_socket[sock].sa.sa.sa_family == AF_INET) {
+ && listen_socket[n->sock].sa.sa.sa_family == AF_INET) {
priority = origpriority;
- ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Setting outgoing packet priority to %d"), priority);
- if(setsockopt(listen_socket[sock].udp, SOL_IP, IP_TOS, &priority, sizeof(priority))) /* SO_PRIORITY doesn't seem to work */
- logger(LOG_ERR, _("System call `%s' failed: %s"), "setsockopt", strerror(errno));
+ logger(DEBUG_TRAFFIC, LOG_DEBUG, "Setting outgoing packet priority to %d", priority);
+ if(setsockopt(listen_socket[n->sock].udp, SOL_IP, IP_TOS, &priority, sizeof(priority))) /* SO_PRIORITY doesn't seem to work */
+ logger(DEBUG_ALWAYS, LOG_ERR, "System call `%s' failed: %s", "setsockopt", strerror(errno));
}
#endif
- if((sendto(listen_socket[sock].udp, (char *) &inpkt->seqno, inpkt->len, 0, &(n->address.sa), SALEN(n->address.sa))) < 0) {
- if(errno == EMSGSIZE) {
+ if(sendto(listen_socket[sock].udp, (char *) &inpkt->seqno, inpkt->len, 0, sa, sl) < 0 && !sockwouldblock(sockerrno)) {
+ if(sockmsgsize(sockerrno)) {
if(n->maxmtu >= origlen)
n->maxmtu = origlen - 1;
if(n->mtu >= origlen)
n->mtu = origlen - 1;
} else
- logger(LOG_ERR, _("Error sending packet to %s (%s): %s"), n->name, n->hostname, strerror(errno));
+ logger(DEBUG_TRAFFIC, LOG_WARNING, "Error sending packet to %s (%s): %s", n->name, n->hostname, sockstrerror(sockerrno));
}
end:
- inpkt->len = origlen;
+ origpkt->len = origlen;
+}
+
+bool send_sptps_data(void *handle, uint8_t type, const char *data, size_t len) {
+ node_t *to = handle;
+
+ if(type >= SPTPS_HANDSHAKE
+ || ((myself->options | to->options) & OPTION_TCPONLY)
+ || (type != PKT_PROBE && len > to->minmtu)) {
+ char buf[len * 4 / 3 + 5];
+ b64encode(data, buf, len);
+ if(!to->status.validkey)
+ return send_request(to->nexthop->connection, "%d %s %s %s -1 -1 -1 %d", ANS_KEY, myself->name, to->name, buf, myself->incompression);
+ else
+ return send_request(to->nexthop->connection, "%d %s %s %d %s", REQ_KEY, myself->name, to->name, type >= SPTPS_HANDSHAKE ? REQ_SPTPS : REQ_PACKET, buf);
+ }
+
+ /* Send the packet */
+
+ struct sockaddr *sa;
+ socklen_t sl;
+ int sock;
+
+ sa = &(to->address.sa);
+ sl = SALEN(to->address.sa);
+ sock = to->sock;
+
+ if(sendto(listen_socket[sock].udp, data, len, 0, sa, sl) < 0 && !sockwouldblock(sockerrno)) {
+ if(sockmsgsize(sockerrno)) {
+ if(to->maxmtu >= len)
+ to->maxmtu = len - 1;
+ if(to->mtu >= len)
+ to->mtu = len - 1;
+ } else {
+ logger(DEBUG_TRAFFIC, LOG_WARNING, "Error sending UDP SPTPS packet to %s (%s): %s", to->name, to->hostname, sockstrerror(sockerrno));
+ return false;
+ }
+ }
+
+ return true;
+}
+
+bool receive_sptps_record(void *handle, uint8_t type, const char *data, uint16_t len) {
+ node_t *from = handle;
+
+ if(type == SPTPS_HANDSHAKE) {
+ from->status.validkey = true;
+ from->status.waitingforkey = false;
+ logger(DEBUG_META, LOG_INFO, "SPTPS key exchange with %s (%s) succesful", from->name, from->hostname);
+ return true;
+ }
+
+ if(len > MTU) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Packet from %s (%s) larger than maximum supported size (%d > %d)", from->name, from->hostname, len, MTU);
+ return false;
+ }
+
+ vpn_packet_t inpkt;
+
+ if(type == PKT_PROBE) {
+ inpkt.len = len;
+ memcpy(inpkt.data, data, len);
+ mtu_probe_h(from, &inpkt, len);
+ return true;
+ }
+
+ if(type & ~(PKT_COMPRESSED | PKT_MAC)) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Unexpected SPTPS record type %d len %d from %s (%s)", type, len, from->name, from->hostname);
+ return false;
+ }
+
+ /* Check if we have the headers we need */
+ if(routing_mode != RMODE_ROUTER && !(type & PKT_MAC)) {
+ logger(DEBUG_TRAFFIC, LOG_ERR, "Received packet from %s (%s) without MAC header (maybe Mode is not set correctly)", from->name, from->hostname);
+ return false;
+ } else if(routing_mode == RMODE_ROUTER && (type & PKT_MAC)) {
+ logger(DEBUG_TRAFFIC, LOG_WARNING, "Received packet from %s (%s) with MAC header (maybe Mode is not set correctly)", from->name, from->hostname);
+ }
+
+ int offset = (type & PKT_MAC) ? 0 : 14;
+ if(type & PKT_COMPRESSED) {
+ len = uncompress_packet(inpkt.data + offset, (const uint8_t *)data, len, from->incompression);
+ if(len < 0) {
+ return false;
+ } else {
+ inpkt.len = len + offset;
+ }
+ if(inpkt.len > MAXSIZE)
+ abort();
+ } else {
+ memcpy(inpkt.data + offset, data, len);
+ inpkt.len = len + offset;
+ }
+
+ /* Generate the Ethernet packet type if necessary */
+ if(offset) {
+ switch(inpkt.data[14] >> 4) {
+ case 4:
+ inpkt.data[12] = 0x08;
+ inpkt.data[13] = 0x00;
+ break;
+ case 6:
+ inpkt.data[12] = 0x86;
+ inpkt.data[13] = 0xDD;
+ break;
+ default:
+ logger(DEBUG_TRAFFIC, LOG_ERR,
+ "Unknown IP version %d while reading packet from %s (%s)",
+ inpkt.data[14] >> 4, from->name, from->hostname);
+ return false;
+ }
+ }
+
+ receive_packet(from, &inpkt);
+ return true;
}
/*
send a packet to the given vpn ip.
*/
-void send_packet(const node_t *n, vpn_packet_t *packet)
-{
+void send_packet(node_t *n, vpn_packet_t *packet) {
node_t *via;
- cp();
-
if(n == myself) {
if(overwrite_mac)
memcpy(packet->data, mymac.x, ETH_ALEN);
- write_packet(packet);
+ n->out_packets++;
+ n->out_bytes += packet->len;
+ devops.write(packet);
return;
}
- ifdebug(TRAFFIC) logger(LOG_ERR, _("Sending packet of %d bytes to %s (%s)"),
+ logger(DEBUG_TRAFFIC, LOG_ERR, "Sending packet of %d bytes to %s (%s)",
packet->len, n->name, n->hostname);
if(!n->status.reachable) {
- ifdebug(TRAFFIC) logger(LOG_INFO, _("Node %s (%s) is not reachable"),
+ logger(DEBUG_TRAFFIC, LOG_INFO, "Node %s (%s) is not reachable",
n->name, n->hostname);
return;
}
- via = (n->via == myself) ? n->nexthop : n->via;
+ n->out_packets++;
+ n->out_bytes += packet->len;
+
+ if(n->status.sptps) {
+ send_sptps_packet(n, packet);
+ return;
+ }
+
+ via = (packet->priority == -1 || n->via == myself) ? n->nexthop : n->via;
if(via != n)
- ifdebug(TRAFFIC) logger(LOG_ERR, _("Sending packet to %s via %s (%s)"),
+ logger(DEBUG_TRAFFIC, LOG_INFO, "Sending packet to %s via %s (%s)",
n->name, via->name, n->via->hostname);
- if((myself->options | via->options) & OPTION_TCPONLY) {
+ if(packet->priority == -1 || ((myself->options | via->options) & OPTION_TCPONLY)) {
if(!send_tcppacket(via->connection, packet))
terminate_connection(via->connection, true);
} else
/* Broadcast a packet using the minimum spanning tree */
-void broadcast_packet(const node_t *from, vpn_packet_t *packet)
-{
- avl_node_t *node;
- connection_t *c;
+void broadcast_packet(const node_t *from, vpn_packet_t *packet) {
+ // Always give ourself a copy of the packet.
+ if(from != myself)
+ send_packet(myself, packet);
- cp();
+ // In TunnelServer mode, do not forward broadcast packets.
+ // The MST might not be valid and create loops.
+ if(tunnelserver || broadcast_mode == BMODE_NONE)
+ return;
- ifdebug(TRAFFIC) logger(LOG_INFO, _("Broadcasting packet of %d bytes from %s (%s)"),
+ logger(DEBUG_TRAFFIC, LOG_INFO, "Broadcasting packet of %d bytes from %s (%s)",
packet->len, from->name, from->hostname);
- for(node = connection_tree->head; node; node = node->next) {
- c = node->data;
+ switch(broadcast_mode) {
+ // In MST mode, broadcast packets travel via the Minimum Spanning Tree.
+ // This guarantees all nodes receive the broadcast packet, and
+ // usually distributes the sending of broadcast packets over all nodes.
+ case BMODE_MST:
+ for list_each(connection_t, c, connection_list)
+ if(c->status.active && c->status.mst && c != from->nexthop->connection)
+ send_packet(c->node, packet);
+ break;
+
+ // In direct mode, we send copies to each node we know of.
+ // However, this only reaches nodes that can be reached in a single hop.
+ // We don't have enough information to forward broadcast packets in this case.
+ case BMODE_DIRECT:
+ if(from != myself)
+ break;
- if(c->status.active && c->status.mst && c != from->nexthop->connection)
- send_packet(c->node, packet);
+ for splay_each(node_t, n, node_tree)
+ if(n->status.reachable && ((n->via == myself && n->nexthop == n) || n->via == n))
+ send_packet(n, packet);
+ break;
+
+ default:
+ break;
}
}
-void flush_queue(node_t *n)
-{
- list_node_t *node, *next;
+static node_t *try_harder(const sockaddr_t *from, const vpn_packet_t *pkt) {
+ node_t *n = NULL;
+ bool hard = false;
+ static time_t last_hard_try = 0;
+ time_t now = time(NULL);
- cp();
+ for splay_each(edge_t, e, edge_weight_tree) {
+ if(!e->to->status.reachable || e->to == myself)
+ continue;
- ifdebug(TRAFFIC) logger(LOG_INFO, _("Flushing queue for %s (%s)"), n->name, n->hostname);
+ if(sockaddrcmp_noport(from, &e->address)) {
+ if(last_hard_try == now)
+ continue;
+ hard = true;
+ }
+
+ if(!try_mac(e->to, pkt))
+ continue;
- for(node = n->queue->head; node; node = next) {
- next = node->next;
- send_udppacket(n, node->data);
- list_delete_node(n->queue, node);
+ n = e->to;
+ break;
}
+
+ if(hard)
+ last_hard_try = now;
+
+ last_hard_try = now;
+ return n;
}
-void handle_incoming_vpn_data(int sock)
-{
+void handle_incoming_vpn_data(int sock, short events, void *data) {
vpn_packet_t pkt;
char *hostname;
- sockaddr_t from;
- socklen_t fromlen = sizeof(from);
+ sockaddr_t from = {{0}};
+ socklen_t fromlen = sizeof from;
node_t *n;
+ int len;
- cp();
-
- pkt.len = recvfrom(sock, (char *) &pkt.seqno, MAXSIZE, 0, &from.sa, &fromlen);
+ len = recvfrom(sock, (char *) &pkt.seqno, MAXSIZE, 0, &from.sa, &fromlen);
- if(pkt.len < 0) {
- logger(LOG_ERR, _("Receiving packet failed: %s"), strerror(errno));
+ if(len <= 0 || len > MAXSIZE) {
+ if(!sockwouldblock(sockerrno))
+ logger(DEBUG_ALWAYS, LOG_ERR, "Receiving packet failed: %s", sockstrerror(sockerrno));
return;
}
+ pkt.len = len;
+
sockaddrunmap(&from); /* Some braindead IPv6 implementations do stupid things. */
n = lookup_node_udp(&from);
if(!n) {
- hostname = sockaddr2hostname(&from);
- logger(LOG_WARNING, _("Received UDP packet from unknown source %s"),
- hostname);
- free(hostname);
- return;
+ n = try_harder(&from, &pkt);
+ if(n)
+ update_node_udp(n, &from);
+ else if(debug_level >= DEBUG_PROTOCOL) {
+ hostname = sockaddr2hostname(&from);
+ logger(DEBUG_PROTOCOL, LOG_WARNING, "Received UDP packet from unknown source %s", hostname);
+ free(hostname);
+ return;
+ }
+ else
+ return;
}
+ n->sock = (intptr_t)data;
+
receive_udppacket(n, &pkt);
}
+
+void handle_device_data(int sock, short events, void *data) {
+ vpn_packet_t packet;
+
+ packet.priority = 0;
+
+ if(devops.read(&packet)) {
+ myself->in_packets++;
+ myself->in_bytes += packet.len;
+ route(myself, &packet);
+ }
+}