/*
net_packet.c -- Handles in- and outgoing VPN packets
Copyright (C) 1998-2005 Ivo Timmermans,
- 2000-2015 Guus Sliepen <guus@tinc-vpn.org>
+ 2000-2016 Guus Sliepen <guus@tinc-vpn.org>
2010 Timothy Redaelli <timothy@redaelli.eu>
2010 Brandon Black <blblack@gmail.com>
vpn_packet_t packet;
int len, i;
int timeout = 1;
-
+
n->mtuprobes++;
n->mtuevent = NULL;
}
if(n->mtuprobes == 30 || (n->mtuprobes < 30 && n->minmtu >= n->maxmtu)) {
- if(n->minmtu > n->maxmtu)
+ if(n->minmtu > n->maxmtu) {
n->minmtu = n->maxmtu;
- else
+ } else {
n->maxmtu = n->minmtu;
+ }
+
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);
n->mtuprobes = 31;
for(i = 0; i < 4 + localdiscovery; i++) {
if(i == 0) {
- if(n->mtuprobes < 30 || n->maxmtu + 8 >= MTU)
+ if(n->mtuprobes < 30 || n->maxmtu + 8 >= MTU) {
continue;
+ }
+
len = n->maxmtu + 8;
} else if(n->maxmtu <= n->minmtu) {
len = n->maxmtu;
len = n->minmtu + 1 + rand() % (n->maxmtu - n->minmtu);
}
- if(len < 64)
+ if(len < 64) {
len = 64;
-
+ }
+
memset(packet.data, 0, 14);
- RAND_pseudo_bytes(packet.data + 14, len - 14);
+ RAND_bytes(packet.data + 14, len - 14);
packet.len = len;
- if(i >= 4 && n->mtuprobes <= 10)
+
+ if(i >= 4 && n->mtuprobes <= 10) {
packet.priority = -1;
- else
+ } else {
packet.priority = 0;
+ }
ifdebug(TRAFFIC) logger(LOG_INFO, "Sending MTU probe length %d to %s (%s)", len, n->name, n->hostname);
send_udppacket(n, packet);
} else {
if(n->mtuprobes > 30) {
- if (len == n->maxmtu + 8) {
+ if(len == n->maxmtu + 8) {
ifdebug(TRAFFIC) logger(LOG_INFO, "Increase in PMTU to %s (%s) detected, restarting PMTU discovery", n->name, n->hostname);
n->maxmtu = MTU;
n->mtuprobes = 10;
return;
}
- if(n->minmtu)
+ if(n->minmtu) {
n->mtuprobes = 30;
- else
+ } else {
n->mtuprobes = 1;
+ }
}
- if(len > n->maxmtu)
+ if(len > n->maxmtu) {
len = n->maxmtu;
- if(n->minmtu < len)
+ }
+
+ if(n->minmtu < len) {
n->minmtu = len;
+ }
}
}
lzo1x_1_compress(source, len, dest, &lzolen, lzo_wrkmem);
return lzolen;
#else
- return -1;
+ return 0;
#endif
} else if(level < 10) {
#ifdef HAVE_ZLIB
unsigned long destlen = MAXSIZE;
- if(compress2(dest, &destlen, source, len, level) == Z_OK)
+
+ if(compress2(dest, &destlen, source, len, level) == Z_OK) {
return destlen;
- else
+ } else
#endif
- return -1;
+ return 0;
} else {
#ifdef HAVE_LZO
lzo_uint lzolen = MAXSIZE;
lzo1x_999_compress(source, len, dest, &lzolen, lzo_wrkmem);
return lzolen;
#else
- return -1;
+ return 0;
#endif
}
-
- return -1;
+
+ return 0;
}
static length_t uncompress_packet(uint8_t *dest, const uint8_t *source, length_t len, int level) {
} else if(level > 9) {
#ifdef HAVE_LZO
lzo_uint lzolen = MAXSIZE;
- if(lzo1x_decompress_safe(source, len, dest, &lzolen, NULL) == LZO_E_OK)
+
+ if(lzo1x_decompress_safe(source, len, dest, &lzolen, NULL) == LZO_E_OK) {
return lzolen;
- else
+ } else
#endif
- return -1;
+ return 0;
}
+
#ifdef HAVE_ZLIB
else {
unsigned long destlen = MAXSIZE;
- if(uncompress(dest, &destlen, source, len) == Z_OK)
+
+ if(uncompress(dest, &destlen, source, len) == Z_OK) {
return destlen;
- else
- return -1;
+ } else {
+ return 0;
+ }
}
+
#endif
return -1;
static void receive_packet(node_t *n, vpn_packet_t *packet) {
ifdebug(TRAFFIC) logger(LOG_DEBUG, "Received packet of %d bytes from %s (%s)",
- packet->len, n->name, n->hostname);
+ packet->len, n->name, n->hostname);
route(n, packet);
}
static bool try_mac(const node_t *n, const vpn_packet_t *inpkt) {
unsigned char hmac[EVP_MAX_MD_SIZE];
- if(!n->indigest || !n->inmaclength || !n->inkey || inpkt->len < sizeof inpkt->seqno + n->inmaclength)
+ if(!n->indigest || !n->inmaclength || !n->inkey || inpkt->len < sizeof(inpkt->seqno) + n->inmaclength) {
return false;
+ }
HMAC(n->indigest, n->inkey, n->inkeylength, (unsigned char *) &inpkt->seqno, inpkt->len - n->inmaclength, (unsigned char *)hmac, NULL);
vpn_packet_t *outpkt;
int outlen, outpad;
unsigned char hmac[EVP_MAX_MD_SIZE];
- int i;
if(!n->inkey) {
ifdebug(TRAFFIC) logger(LOG_DEBUG, "Got packet from %s (%s) but he hasn't got our key yet",
- n->name, n->hostname);
+ n->name, n->hostname);
return;
}
if(inpkt->len < sizeof(inpkt->seqno) + n->inmaclength) {
ifdebug(TRAFFIC) logger(LOG_DEBUG, "Got too short packet from %s (%s)",
- n->name, n->hostname);
+ n->name, n->hostname);
return;
}
if(n->indigest && n->inmaclength) {
inpkt->len -= n->inmaclength;
HMAC(n->indigest, n->inkey, n->inkeylength,
- (unsigned char *) &inpkt->seqno, inpkt->len, (unsigned char *)hmac, NULL);
+ (unsigned char *) &inpkt->seqno, inpkt->len, (unsigned char *)hmac, NULL);
if(memcmp_constant_time(hmac, (char *) &inpkt->seqno + inpkt->len, n->inmaclength)) {
ifdebug(TRAFFIC) logger(LOG_DEBUG, "Got unauthenticated packet from %s (%s)",
- n->name, n->hostname);
+ n->name, n->hostname);
return;
}
}
if(n->incipher) {
outpkt = pkt[nextpkt++];
- if(!EVP_DecryptInit_ex(&n->inctx, NULL, NULL, NULL, NULL)
- || !EVP_DecryptUpdate(&n->inctx, (unsigned char *) &outpkt->seqno, &outlen,
- (unsigned char *) &inpkt->seqno, inpkt->len)
- || !EVP_DecryptFinal_ex(&n->inctx, (unsigned char *) &outpkt->seqno + outlen, &outpad)) {
+ if(!EVP_DecryptInit_ex(n->inctx, NULL, NULL, NULL, NULL)
+ || !EVP_DecryptUpdate(n->inctx, (unsigned char *) &outpkt->seqno, &outlen,
+ (unsigned char *) &inpkt->seqno, inpkt->len)
+ || !EVP_DecryptFinal_ex(n->inctx, (unsigned 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));
+ n->name, n->hostname, ERR_error_string(ERR_get_error(), NULL));
return;
}
-
+
outpkt->len = outlen + outpad;
inpkt = outpkt;
}
if(inpkt->seqno != n->received_seqno + 1) {
if(inpkt->seqno >= n->received_seqno + replaywin * 8) {
if(n->farfuture++ < replaywin >> 2) {
- logger(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);
+ ifdebug(TRAFFIC) logger(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(LOG_WARNING, "Lost %d packets from %s (%s)",
- inpkt->seqno - n->received_seqno - 1, n->name, n->hostname);
+
+ ifdebug(TRAFFIC) logger(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) {
+ } 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(LOG_WARNING, "Got late or replayed packet from %s (%s), seqno %d, last received %d",
- n->name, n->hostname, inpkt->seqno, n->received_seqno);
+ ifdebug(TRAFFIC) 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);
return;
}
} else {
- for(i = n->received_seqno + 1; i < inpkt->seqno; i++)
+ for(uint32_t i = n->received_seqno + 1; i < inpkt->seqno; i++) {
n->late[(i / 8) % replaywin] |= 1 << i % 8;
+ }
}
}
n->late[(inpkt->seqno / 8) % replaywin] &= ~(1 << inpkt->seqno % 8);
}
- if(inpkt->seqno > n->received_seqno)
+ if(inpkt->seqno > n->received_seqno) {
n->received_seqno = inpkt->seqno;
-
- if(n->received_seqno > MAX_SEQNO)
+ }
+
+ if(n->received_seqno > MAX_SEQNO) {
keyexpires = 0;
+ }
/* Decompress the packet */
if(n->incompression) {
outpkt = pkt[nextpkt++];
- if((outpkt->len = uncompress_packet(outpkt->data, inpkt->data, inpkt->len, n->incompression)) < 0) {
+ if(!(outpkt->len = uncompress_packet(outpkt->data, inpkt->data, inpkt->len, n->incompression))) {
ifdebug(TRAFFIC) logger(LOG_ERR, "Error while uncompressing packet from %s (%s)",
- n->name, n->hostname);
+ n->name, n->hostname);
return;
}
inpkt = outpkt;
- origlen -= MTU/64 + 20;
+ origlen -= MTU / 64 + 20;
}
inpkt->priority = 0;
- if(!inpkt->data[12] && !inpkt->data[13])
+ if(!inpkt->data[12] && !inpkt->data[13]) {
mtu_probe_h(n, inpkt, origlen);
- else
+ } else {
receive_packet(n, inpkt);
+ }
}
-void receive_tcppacket(connection_t *c, const char *buffer, int len) {
+void receive_tcppacket(connection_t *c, const char *buffer, length_t len) {
vpn_packet_t outpkt;
- if(len > sizeof outpkt.data)
+ if(len > sizeof(outpkt.data)) {
return;
+ }
outpkt.len = len;
- if(c->options & OPTION_TCPONLY)
+
+ if(c->options & OPTION_TCPONLY) {
outpkt.priority = 0;
- else
+ } else {
outpkt.priority = -1;
+ }
+
memcpy(outpkt.data, buffer, len);
receive_packet(c->node, &outpkt);
if(!n->status.validkey) {
ifdebug(TRAFFIC) logger(LOG_INFO,
- "No valid key known yet for %s (%s), forwarding via TCP",
- n->name, n->hostname);
+ "No valid key known yet for %s (%s), forwarding via TCP",
+ n->name, n->hostname);
if(n->last_req_key + 10 <= now) {
send_req_key(n);
if(n->options & OPTION_PMTU_DISCOVERY && inpkt->len > n->minmtu && (inpkt->data[12] | inpkt->data[13])) {
ifdebug(TRAFFIC) logger(LOG_INFO,
- "Packet for %s (%s) larger than minimum MTU, forwarding via %s",
- n->name, n->hostname, n != n->nexthop ? n->nexthop->name : "TCP");
+ "Packet for %s (%s) larger than minimum MTU, forwarding via %s",
+ n->name, n->hostname, n != n->nexthop ? n->nexthop->name : "TCP");
- if(n != n->nexthop)
+ if(n != n->nexthop) {
send_packet(n->nexthop, origpkt);
- else
+ } else {
send_tcppacket(n->nexthop->connection, origpkt);
+ }
return;
}
if(n->outcompression) {
outpkt = pkt[nextpkt++];
- if((outpkt->len = compress_packet(outpkt->data, inpkt->data, inpkt->len, n->outcompression)) < 0) {
+ if(!(outpkt->len = compress_packet(outpkt->data, inpkt->data, inpkt->len, n->outcompression))) {
ifdebug(TRAFFIC) logger(LOG_ERR, "Error while compressing packet to %s (%s)",
- n->name, n->hostname);
+ n->name, n->hostname);
return;
}
if(n->outcipher) {
outpkt = pkt[nextpkt++];
- if(!EVP_EncryptInit_ex(&n->outctx, NULL, NULL, NULL, NULL)
- || !EVP_EncryptUpdate(&n->outctx, (unsigned char *) &outpkt->seqno, &outlen,
- (unsigned char *) &inpkt->seqno, inpkt->len)
- || !EVP_EncryptFinal_ex(&n->outctx, (unsigned char *) &outpkt->seqno + outlen, &outpad)) {
+ if(!EVP_EncryptInit_ex(n->outctx, NULL, NULL, NULL, NULL)
+ || !EVP_EncryptUpdate(n->outctx, (unsigned char *) &outpkt->seqno, &outlen,
+ (unsigned char *) &inpkt->seqno, inpkt->len)
+ || !EVP_EncryptFinal_ex(n->outctx, (unsigned 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));
+ n->name, n->hostname, ERR_error_string(ERR_get_error(), NULL));
goto end;
}
if(n->outdigest && n->outmaclength) {
HMAC(n->outdigest, n->outkey, n->outkeylength, (unsigned char *) &inpkt->seqno,
- inpkt->len, (unsigned char *) &inpkt->seqno + inpkt->len, NULL);
+ inpkt->len, (unsigned char *) &inpkt->seqno + inpkt->len, NULL);
inpkt->len += n->outmaclength;
}
if(origpriority == -1 && n->prevedge) {
sock = rand() % listen_sockets;
- memset(&broadcast, 0, sizeof broadcast);
+ memset(&broadcast, 0, sizeof(broadcast));
+
if(listen_socket[sock].sa.sa.sa_family == AF_INET6) {
broadcast.in6.sin6_family = AF_INET6;
broadcast.in6.sin6_addr.s6_addr[0x0] = 0xff;
broadcast.in.sin_addr.s_addr = -1;
broadcast.in.sin_port = n->prevedge->address.in.sin_port;
}
+
sa = &broadcast.sa;
sl = SALEN(broadcast.sa);
} else {
- if(origpriority == -1)
+ if(origpriority == -1) {
origpriority = 0;
+ }
sa = &(n->address.sa);
sl = SALEN(n->address.sa);
if(priorityinheritance && origpriority != listen_socket[n->sock].priority) {
listen_socket[n->sock].priority = origpriority;
+
switch(listen_socket[n->sock].sa.sa.sa_family) {
#if defined(SOL_IP) && defined(IP_TOS)
+
case AF_INET:
ifdebug(TRAFFIC) logger(LOG_DEBUG, "Setting IPv4 outgoing packet priority to %d", origpriority);
- if(setsockopt(listen_socket[n->sock].udp, SOL_IP, IP_TOS, (void *)&origpriority, sizeof(origpriority))) /* SO_PRIORITY doesn't seem to work */
+
+ if(setsockopt(listen_socket[n->sock].udp, SOL_IP, IP_TOS, (void *)&origpriority, sizeof(origpriority))) { /* SO_PRIORITY doesn't seem to work */
logger(LOG_ERR, "System call `%s' failed: %s", "setsockopt", strerror(errno));
+ }
+
break;
#endif
#if defined(IPPROTO_IPV6) && defined(IPV6_TCLASS)
+
case AF_INET6:
ifdebug(TRAFFIC) logger(LOG_DEBUG, "Setting IPv6 outgoing packet priority to %d", origpriority);
- if(setsockopt(listen_socket[n->sock].udp, IPPROTO_IPV6, IPV6_TCLASS, (void *)&origpriority, sizeof(origpriority)))
+
+ if(setsockopt(listen_socket[n->sock].udp, IPPROTO_IPV6, IPV6_TCLASS, (void *)&origpriority, sizeof(origpriority))) {
logger(LOG_ERR, "System call `%s' failed: %s", "setsockopt", strerror(errno));
+ }
+
break;
#endif
+
default:
break;
}
if(sendto(listen_socket[sock].udp, (char *) &inpkt->seqno, inpkt->len, 0, sa, sl) < 0 && !sockwouldblock(sockerrno)) {
if(sockmsgsize(sockerrno)) {
- if(n->maxmtu >= origlen)
+ if(n->maxmtu >= origlen) {
n->maxmtu = origlen - 1;
- if(n->mtu >= origlen)
+ }
+
+ if(n->mtu >= origlen) {
n->mtu = origlen - 1;
- } else
+ }
+ } else {
ifdebug(TRAFFIC) logger(LOG_WARNING, "Error sending packet to %s (%s): %s", n->name, n->hostname, sockstrerror(sockerrno));
+ }
}
end:
node_t *via;
if(n == myself) {
- if(overwrite_mac)
- memcpy(packet->data, mymac.x, ETH_ALEN);
+ if(overwrite_mac) {
+ memcpy(packet->data, mymac.x, ETH_ALEN);
+ }
+
devops.write(packet);
return;
}
ifdebug(TRAFFIC) logger(LOG_ERR, "Sending packet of %d bytes to %s (%s)",
- packet->len, n->name, n->hostname);
+ packet->len, n->name, n->hostname);
if(!n->status.reachable) {
ifdebug(TRAFFIC) logger(LOG_INFO, "Node %s (%s) is not reachable",
- n->name, n->hostname);
+ n->name, n->hostname);
return;
}
if(via != n)
ifdebug(TRAFFIC) logger(LOG_INFO, "Sending packet to %s via %s (%s)",
- n->name, via->name, n->via->hostname);
+ n->name, via->name, n->via->hostname);
if(packet->priority == -1 || ((myself->options | via->options) & OPTION_TCPONLY)) {
- if(!send_tcppacket(via->connection, packet))
+ if(!send_tcppacket(via->connection, packet)) {
terminate_connection(via->connection, true);
- } else
+ }
+ } else {
send_udppacket(via, packet);
+ }
}
/* Broadcast a packet using the minimum spanning tree */
node_t *n;
// Always give ourself a copy of the packet.
- if(from != myself)
+ if(from != myself) {
send_packet(myself, packet);
+ }
// In TunnelServer mode, do not forward broadcast packets.
- // The MST might not be valid and create loops.
- if(tunnelserver || broadcast_mode == BMODE_NONE)
+ // 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)",
- packet->len, from->name, from->hostname);
+ packet->len, from->name, from->hostname);
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(node = connection_tree->head; node; node = node->next) {
- c = node->data;
-
- if(c->status.active && c->status.mst && c != from->nexthop->connection)
- send_packet(c->node, packet);
+ // 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(node = connection_tree->head; node; node = node->next) {
+ c = node->data;
+
+ 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;
+ 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;
+ }
- for(node = node_udp_tree->head; node; node = node->next) {
- n = node->data;
+ for(node = node_udp_tree->head; node; node = node->next) {
+ n = node->data;
- if(n->status.reachable && n != myself && ((n->via == myself && n->nexthop == n) || n->via == n))
- send_packet(n, packet);
+ if(n->status.reachable && n != myself && ((n->via == myself && n->nexthop == n) || n->via == n)) {
+ send_packet(n, packet);
}
- break;
+ }
- default:
- break;
+ break;
+
+ default:
+ break;
}
}
for(node = edge_weight_tree->head; node; node = node->next) {
e = node->data;
- if(e->to == myself)
+ if(e->to == myself) {
continue;
+ }
- if(last_hard_try == now && sockaddrcmp_noport(from, &e->address))
+ if(last_hard_try == now && sockaddrcmp_noport(from, &e->address)) {
continue;
+ }
- if(!try_mac(e->to, pkt))
+ if(!try_mac(e->to, pkt)) {
continue;
+ }
n = e->to;
break;
socklen_t fromlen = sizeof(from);
node_t *n;
- pkt.len = recvfrom(listen_socket[sock].udp, (char *) &pkt.seqno, MAXSIZE, 0, &from.sa, &fromlen);
+ ssize_t len = recvfrom(listen_socket[sock].udp, (char *) &pkt.seqno, MAXSIZE, 0, &from.sa, &fromlen);
- if(pkt.len < 0) {
- if(!sockwouldblock(sockerrno))
+ if(len <= 0 || len > UINT16_MAX) {
+ if(len >= 0) {
+ logger(LOG_ERR, "Receiving packet with invalid size");
+ } else if(!sockwouldblock(sockerrno)) {
logger(LOG_ERR, "Receiving packet failed: %s", sockstrerror(sockerrno));
+ }
+
return;
}
- sockaddrunmap(&from); /* Some braindead IPv6 implementations do stupid things. */
+ pkt.len = len;
+ sockaddrunmap(&from); /* Some braindead IPv6 implementations do stupid things. */
n = lookup_node_udp(&from);
if(!n) {
n = try_harder(&from, &pkt);
- if(n)
+
+ if(n) {
update_node_udp(n, &from);
- else ifdebug(PROTOCOL) {
+ } else ifdebug(PROTOCOL) {
hostname = sockaddr2hostname(&from);
logger(LOG_WARNING, "Received UDP packet from unknown source %s", hostname);
free(hostname);
return;
- }
- else
+ } else {
return;
+ }
}
n->sock = sock;
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