/*
net_packet.c -- Handles in- and outgoing VPN packets
- Copyright (C) 2014 Guus Sliepen <guus@meshlink.io>
+ Copyright (C) 2014-2017 Guus Sliepen <guus@meshlink.io>
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
#include "system.h"
-#ifdef HAVE_ZLIB
-#include <zlib.h>
-#endif
-
#include "conf.h"
#include "connection.h"
#include "crypto.h"
static void send_udppacket(meshlink_handle_t *mesh, node_t *, vpn_packet_t *);
-unsigned replaywin = 16;
-
#define MAX_SEQNO 1073741824
/* mtuprobes == 1..30: initial discovery, send bursts with 1 second interval
n->mtuprobes++;
if(!n->status.reachable || !n->status.validkey) {
- logger(mesh, MESHLINK_INFO, "Trying to send MTU probe to unreachable or rekeying node %s (%s)", n->name, n->hostname);
+ logger(mesh, MESHLINK_INFO, "Trying to send MTU probe to unreachable or rekeying node %s", n->name);
n->mtuprobes = 0;
return;
}
goto end;
}
- logger(mesh, MESHLINK_INFO, "%s (%s) did not respond to UDP ping, restarting PMTU discovery", n->name, n->hostname);
+ logger(mesh, MESHLINK_INFO, "%s did not respond to UDP ping, restarting PMTU discovery", n->name);
n->status.udp_confirmed = false;
n->mtuprobes = 1;
n->minmtu = 0;
}
if(n->mtuprobes >= 10 && n->mtuprobes < 32 && !n->minmtu) {
- logger(mesh, MESHLINK_INFO, "No response to MTU probes from %s (%s)", n->name, n->hostname);
+ logger(mesh, MESHLINK_INFO, "No response to MTU probes from %s", n->name);
n->mtuprobes = 31;
}
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;
- logger(mesh, MESHLINK_INFO, "Fixing MTU of %s (%s) to %d after %d probes", n->name, n->hostname, n->mtu, n->mtuprobes);
+ logger(mesh, MESHLINK_INFO, "Fixing MTU of %s to %d after %d probes", n->name, n->mtu, n->mtuprobes);
n->mtuprobes = 31;
}
int len;
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;
+ }
vpn_packet_t packet;
packet.probe = true;
packet.len = len;
n->status.broadcast = i >= 4 && n->mtuprobes <= 10 && n->prevedge;
- logger(mesh, MESHLINK_INFO, "Sending MTU probe length %d to %s (%s)", len, n->name, n->hostname);
+ logger(mesh, MESHLINK_DEBUG, "Sending MTU probe length %d to %s", len, n->name);
send_udppacket(mesh, n, &packet);
}
n->status.broadcast = false;
- n->probe_counter = 0;
- gettimeofday(&n->probe_time, NULL);
-
- /* Calculate the packet loss of incoming traffic by comparing the rate of
- packets received to the rate with which the sequence number has increased.
- */
-
- if(n->received > n->prev_received)
- n->packetloss = 1.0 - (n->received - n->prev_received) / (float)(n->received_seqno - n->prev_received_seqno);
- else
- n->packetloss = n->received_seqno <= n->prev_received_seqno;
-
- n->prev_received_seqno = n->received_seqno;
- n->prev_received = n->received;
end:
- timeout_set(&mesh->loop, &n->mtutimeout, &(struct timeval){timeout, rand() % 100000});
+ timeout_set(&mesh->loop, &n->mtutimeout, &(struct timeval) {
+ timeout, rand() % 100000
+ });
}
void send_mtu_probe(meshlink_handle_t *mesh, node_t *n) {
- timeout_add(&mesh->loop, &n->mtutimeout, send_mtu_probe_handler, n, &(struct timeval){1, 0});
+ timeout_add(&mesh->loop, &n->mtutimeout, send_mtu_probe_handler, n, &(struct timeval) {
+ 1, 0
+ });
send_mtu_probe_handler(&mesh->loop, n);
}
static void mtu_probe_h(meshlink_handle_t *mesh, node_t *n, vpn_packet_t *packet, uint16_t len) {
- logger(mesh, MESHLINK_INFO, "Got MTU probe length %d from %s (%s)", packet->len, n->name, n->hostname);
+ logger(mesh, MESHLINK_DEBUG, "Got MTU probe length %d from %s", packet->len, n->name);
if(!packet->data[0]) {
/* It's a probe request, send back a reply */
/* If we haven't established the PMTU yet, restart the discovery process. */
if(n->mtuprobes > 30) {
- if (len == n->maxmtu + 8) {
- logger(mesh, MESHLINK_INFO, "Increase in PMTU to %s (%s) detected, restarting PMTU discovery", n->name, n->hostname);
+ if(len == n->maxmtu + 8) {
+ logger(mesh, MESHLINK_INFO, "Increase in PMTU to %s detected, restarting PMTU discovery", n->name);
n->maxmtu = MTU;
n->mtuprobes = 10;
return;
}
- if(n->minmtu)
+ if(n->minmtu) {
n->mtuprobes = 30;
- else
+ } else {
n->mtuprobes = 1;
+ }
}
/* If applicable, raise the minimum supported MTU */
- if(len > n->maxmtu)
+ if(len > n->maxmtu) {
len = n->maxmtu;
- if(n->minmtu < len)
- n->minmtu = len;
-
- /* Calculate RTT and bandwidth.
- The RTT is the time between the MTU probe burst was sent and the first
- reply is received. The bandwidth is measured using the time between the
- arrival of the first and third probe reply.
- */
-
- struct timeval now, diff;
- gettimeofday(&now, NULL);
- timersub(&now, &n->probe_time, &diff);
-
- n->probe_counter++;
-
- if(n->probe_counter == 1) {
- n->rtt = diff.tv_sec + diff.tv_usec * 1e-6;
- n->probe_time = now;
- } else if(n->probe_counter == 3) {
- n->bandwidth = 2.0 * len / (diff.tv_sec + diff.tv_usec * 1e-6);
- logger(mesh, MESHLINK_DEBUG, "%s (%s) RTT %.2f ms, burst bandwidth %.3f Mbit/s, rx packet loss %.2f %%", n->name, n->hostname, n->rtt * 1e3, n->bandwidth * 8e-6, n->packetloss * 1e2);
}
- }
-}
-
-static uint16_t compress_packet(uint8_t *dest, const uint8_t *source, uint16_t len, int level) {
- if(level == 0) {
- memcpy(dest, source, len);
- return len;
- } else if(level == 10) {
- return -1;
- } 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 {
- return -1;
- }
- return -1;
-}
-
-static uint16_t uncompress_packet(uint8_t *dest, const uint8_t *source, uint16_t len, int level) {
- if(level == 0) {
- memcpy(dest, source, len);
- return len;
- } else if(level > 9) {
- return -1;
- }
-#ifdef HAVE_ZLIB
- else {
- unsigned long destlen = MAXSIZE;
- if(uncompress(dest, &destlen, source, len) == Z_OK)
- return destlen;
- else
- return -1;
+ if(n->minmtu < len) {
+ n->minmtu = len;
+ }
}
-#endif
-
- return -1;
}
/* VPN packet I/O */
static void receive_packet(meshlink_handle_t *mesh, node_t *n, vpn_packet_t *packet) {
- logger(mesh, MESHLINK_DEBUG, "Received packet of %d bytes from %s (%s)",
- packet->len, n->name, n->hostname);
+ logger(mesh, MESHLINK_DEBUG, "Received packet of %d bytes from %s", packet->len, n->name);
- if (n->status.blacklisted) {
- logger(mesh, MESHLINK_WARNING, "Dropping packet from blacklisted node %s", n->name);
- } else {
- n->in_packets++;
- n->in_bytes += packet->len;
+ if(n->status.blacklisted) {
+ logger(mesh, MESHLINK_WARNING, "Dropping packet from blacklisted node %s", n->name);
+ } else {
+ n->in_packets++;
+ n->in_bytes += packet->len;
- route(mesh, n, packet);
- }
+ route(mesh, n, packet);
+ }
}
static bool try_mac(meshlink_handle_t *mesh, node_t *n, const vpn_packet_t *inpkt) {
+ (void)mesh;
return sptps_verify_datagram(&n->sptps, inpkt->data, inpkt->len);
}
static void receive_udppacket(meshlink_handle_t *mesh, node_t *n, vpn_packet_t *inpkt) {
if(!n->sptps.state) {
if(!n->status.waitingforkey) {
- logger(mesh, MESHLINK_DEBUG, "Got packet from %s (%s) but we haven't exchanged keys yet", n->name, n->hostname);
+ logger(mesh, MESHLINK_DEBUG, "Got packet from %s but we haven't exchanged keys yet", n->name);
send_req_key(mesh, n);
} else {
- logger(mesh, MESHLINK_DEBUG, "Got packet from %s (%s) but he hasn't got our key yet", n->name, n->hostname);
+ logger(mesh, MESHLINK_DEBUG, "Got packet from %s but he hasn't got our key yet", n->name);
}
- return;
- }
- sptps_receive_data(&n->sptps, inpkt->data, inpkt->len);
-}
-
-void receive_tcppacket(meshlink_handle_t *mesh, connection_t *c, const char *buffer, int len) {
- vpn_packet_t outpkt;
- if(len > sizeof outpkt.data)
return;
+ }
- outpkt.len = len;
- outpkt.tcp = true;
- memcpy(outpkt.data, buffer, len);
-
- receive_packet(mesh, c->node, &outpkt);
+ sptps_receive_data(&n->sptps, inpkt->data, inpkt->len);
}
static void send_sptps_packet(meshlink_handle_t *mesh, node_t *n, vpn_packet_t *origpkt) {
if(!n->status.validkey) {
- logger(mesh, MESHLINK_INFO, "No valid key known yet for %s (%s)", n->name, n->hostname);
- if(!n->status.waitingforkey)
+ logger(mesh, MESHLINK_INFO, "No valid key known yet for %s", n->name);
+
+ if(!n->status.waitingforkey) {
send_req_key(mesh, n);
- else if(n->last_req_key + 10 < mesh->loop.now.tv_sec) {
+ } else if(n->last_req_key + 10 < mesh->loop.now.tv_sec) {
logger(mesh, MESHLINK_DEBUG, "No key from %s after 10 seconds, restarting SPTPS", n->name);
sptps_stop(&n->sptps);
n->status.waitingforkey = false;
send_req_key(mesh, n);
}
+
return;
}
return;
}
- vpn_packet_t outpkt;
-
if(n->outcompression) {
- int len = compress_packet(outpkt.data, origpkt->data, origpkt->len, n->outcompression);
- if(len < 0) {
- logger(mesh, MESHLINK_ERROR, "Error while compressing packet to %s (%s)", n->name, n->hostname);
- } else if(len < origpkt->len) {
- outpkt.len = len;
- origpkt = &outpkt;
- type |= PKT_COMPRESSED;
- }
+ logger(mesh, MESHLINK_ERROR, "Error while compressing packet to %s", n->name);
+ return;
}
sptps_send_record(&n->sptps, type, origpkt->data, origpkt->len);
*sock = n->sock;
/* If the UDP address is confirmed, use it. */
- if(n->status.udp_confirmed)
+ if(n->status.udp_confirmed) {
return;
+ }
/* Send every third packet to n->address; that could be set
to the node's reflexive UDP address discovered during key
exchange. */
static int x = 0;
+
if(++x >= 3) {
x = 0;
return;
static void send_udppacket(meshlink_handle_t *mesh, node_t *n, vpn_packet_t *origpkt) {
if(!n->status.reachable) {
- logger(mesh, MESHLINK_INFO, "Trying to send UDP packet to unreachable node %s (%s)", n->name, n->hostname);
+ logger(mesh, MESHLINK_INFO, "Trying to send UDP packet to unreachable node %s", n->name);
return;
}
- return send_sptps_packet(mesh, n, origpkt);
+ send_sptps_packet(mesh, n, origpkt);
}
bool send_sptps_data(void *handle, uint8_t type, const void *data, size_t len) {
if(type >= SPTPS_HANDSHAKE || ((mesh->self->options | to->options) & OPTION_TCPONLY) || (type != PKT_PROBE && len > to->minmtu)) {
char buf[len * 4 / 3 + 5];
b64encode(data, buf, len);
+
/* If no valid key is known yet, send the packets using ANS_KEY requests,
to ensure we get to learn the reflexive UDP address. */
if(!to->status.validkey) {
const sockaddr_t *sa;
int sock;
- if(to->status.broadcast)
+ if(to->status.broadcast) {
choose_broadcast_address(mesh, to, &sa, &sock);
- else
+ } else {
choose_udp_address(mesh, to, &sa, &sock);
+ }
if(sendto(mesh->listen_socket[sock].udp.fd, data, len, 0, &sa->sa, SALEN(sa->sa)) < 0 && !sockwouldblock(sockerrno)) {
if(sockmsgsize(sockerrno)) {
- if(to->maxmtu >= len)
+ if(to->maxmtu >= len) {
to->maxmtu = len - 1;
- if(to->mtu >= len)
+ }
+
+ if(to->mtu >= len) {
to->mtu = len - 1;
+ }
} else {
- logger(mesh, MESHLINK_WARNING, "Error sending UDP SPTPS packet to %s (%s): %s", to->name, to->hostname, sockstrerror(sockerrno));
+ logger(mesh, MESHLINK_WARNING, "Error sending UDP SPTPS packet to %s: %s", to->name, sockstrerror(sockerrno));
return false;
}
}
if(type == SPTPS_HANDSHAKE) {
if(!from->status.validkey) {
+ logger(mesh, MESHLINK_INFO, "SPTPS key exchange with %s succesful", from->name);
from->status.validkey = true;
from->status.waitingforkey = false;
- logger(mesh, MESHLINK_INFO, "SPTPS key exchange with %s (%s) succesful", from->name, from->hostname);
+
+ if(from->utcp) {
+ utcp_reset_timers(from->utcp);
+ }
}
+
return true;
}
if(len > MTU) {
- logger(mesh, MESHLINK_ERROR, "Packet from %s (%s) larger than maximum supported size (%d > %d)", from->name, from->hostname, len, MTU);
+ logger(mesh, MESHLINK_ERROR, "Packet from %s larger than maximum supported size (%d > %d)", from->name, len, MTU);
return false;
}
}
if(type & ~(PKT_COMPRESSED)) {
- logger(mesh, MESHLINK_ERROR, "Unexpected SPTPS record type %d len %d from %s (%s)", type, len, from->name, from->hostname);
+ logger(mesh, MESHLINK_ERROR, "Unexpected SPTPS record type %d len %d from %s", type, len, from->name);
return false;
}
if(type & PKT_COMPRESSED) {
- uint16_t ulen = uncompress_packet(inpkt.data, (const uint8_t *)data, len, from->incompression);
- if(ulen < 0) {
- return false;
- } else {
- inpkt.len = ulen;
- }
- if(inpkt.len > MAXSIZE)
- abort();
- } else {
- memcpy(inpkt.data, data, len);
- inpkt.len = len;
+ logger(mesh, MESHLINK_ERROR, "Error while decompressing packet from %s", from->name);
+ return false;
}
+ memcpy(inpkt.data, data, len); // TODO: get rid of memcpy
+ inpkt.len = len;
+
receive_packet(mesh, from, &inpkt);
return true;
}
return;
}
- logger(mesh, MESHLINK_DEBUG, "Sending packet of %d bytes to %s (%s)",
- packet->len, n->name, n->hostname);
+ logger(mesh, MESHLINK_DEBUG, "Sending packet of %d bytes to %s", packet->len, n->name);
if(!n->status.reachable) {
- logger(mesh, MESHLINK_WARNING, "Node %s (%s) is not reachable",
- n->name, n->hostname);
+ logger(mesh, MESHLINK_WARNING, "Node %s is not reachable", n->name);
return;
}
void broadcast_packet(meshlink_handle_t *mesh, const node_t *from, vpn_packet_t *packet) {
// Always give ourself a copy of the packet.
- if(from != mesh->self)
+ if(from != mesh->self) {
send_packet(mesh, mesh->self, packet);
+ }
- logger(mesh, MESHLINK_INFO, "Broadcasting packet of %d bytes from %s (%s)",
- packet->len, from->name, from->hostname);
+ logger(mesh, MESHLINK_INFO, "Broadcasting packet of %d bytes from %s", packet->len, from->name);
for list_each(connection_t, c, mesh->connections)
- if(c->status.active && c->status.mst && c != from->nexthop->connection)
+ if(c->status.active && c->status.mst && c != from->nexthop->connection) {
send_packet(mesh, c->node, packet);
+ }
}
static node_t *try_harder(meshlink_handle_t *mesh, const sockaddr_t *from, const vpn_packet_t *pkt) {
static time_t last_hard_try = 0;
for splay_each(edge_t, e, mesh->edges) {
- if(!e->to->status.reachable || e->to == mesh->self)
+ if(!e->to->status.reachable || e->to == mesh->self) {
continue;
+ }
if(sockaddrcmp_noport(from, &e->address)) {
- if(last_hard_try == mesh->loop.now.tv_sec)
+ if(last_hard_try == mesh->loop.now.tv_sec) {
continue;
+ }
+
hard = true;
}
- if(!try_mac(mesh, e->to, pkt))
+ if(!try_mac(mesh, e->to, pkt)) {
continue;
+ }
n = e->to;
break;
}
- if(hard)
+ if(hard) {
last_hard_try = mesh->loop.now.tv_sec;
+ }
last_hard_try = mesh->loop.now.tv_sec;
return n;
}
void handle_incoming_vpn_data(event_loop_t *loop, void *data, int flags) {
+ (void)flags;
meshlink_handle_t *mesh = loop->data;
listen_socket_t *ls = data;
vpn_packet_t pkt;
char *hostname;
- sockaddr_t from = {{0}};
- socklen_t fromlen = sizeof from;
+ sockaddr_t from = {0};
+ socklen_t fromlen = sizeof(from);
node_t *n;
int len;
len = recvfrom(ls->udp.fd, pkt.data, MAXSIZE, 0, &from.sa, &fromlen);
if(len <= 0 || len > MAXSIZE) {
- if(!sockwouldblock(sockerrno))
+ if(!sockwouldblock(sockerrno)) {
logger(mesh, MESHLINK_ERROR, "Receiving packet failed: %s", sockstrerror(sockerrno));
+ }
+
return;
}
if(!n) {
n = try_harder(mesh, &from, &pkt);
- if(n)
+
+ if(n) {
update_node_udp(mesh, n, &from);
- else if(mesh->log_level >= MESHLINK_WARNING) {
+ } else if(mesh->log_level >= MESHLINK_WARNING) {
hostname = sockaddr2hostname(&from);
logger(mesh, MESHLINK_WARNING, "Received UDP packet from unknown source %s", hostname);
free(hostname);
return;
- }
- else
+ } else {
return;
+ }
+ }
+
+ if(n->status.blacklisted) {
+ logger(mesh, MESHLINK_WARNING, "Dropping packet from blacklisted node %s", n->name);
+ return;
}
- if (n->status.blacklisted) {
- logger(mesh, MESHLINK_WARNING, "Dropping packet from blacklisted node %s", n->name);
- return;
- }
n->sock = ls - mesh->listen_socket;
receive_udppacket(mesh, n, &pkt);