#include "meshlink_internal.h"
#include "net.h"
#include "netutl.h"
+#include "pmtu.h"
#include "protocol.h"
#include "route.h"
+#include "sptps.h"
#include "utils.h"
#include "xalloc.h"
-int keylifetime = 0;
-
-static void send_udppacket(meshlink_handle_t *mesh, node_t *, vpn_packet_t *);
-
-#define MAX_SEQNO 1073741824
-
-/* 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 at least three, with random sizes between the
- lower and upper boundaries for the MTU thus far discovered.
-
- After the initial discovery, a fourth packet is added to each batch with a
- size larger than the currently known PMTU, to test if the PMTU has increased.
-
- In case local discovery is enabled, another packet is added to each batch,
- which will be broadcast to the local network.
-
-*/
-
-static void send_mtu_probe_handler(event_loop_t *loop, void *data) {
- meshlink_handle_t *mesh = loop->data;
- node_t *n = data;
- int timeout = 1;
-
- n->mtuprobes++;
-
- if(!n->status.reachable || !n->status.validkey) {
- logger(mesh, MESHLINK_INFO, "Trying to send MTU probe to unreachable or rekeying node %s", n->name);
- n->mtuprobes = 0;
- return;
- }
-
- if(n->mtuprobes > 32) {
- if(!n->minmtu) {
- n->mtuprobes = 31;
- timeout = mesh->pinginterval;
- goto end;
- }
-
- 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;
- n->maxmtu = MTU;
- }
-
- if(n->mtuprobes >= 10 && n->mtuprobes < 32 && !n->minmtu) {
- 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) {
- n->minmtu = n->maxmtu;
- } else {
- n->maxmtu = n->minmtu;
- }
-
- n->mtu = n->minmtu;
- logger(mesh, MESHLINK_INFO, "Fixing MTU of %s to %d after %d probes", n->name, n->mtu, n->mtuprobes);
- n->mtuprobes = 31;
- }
-
- if(n->mtuprobes == 31) {
- timeout = mesh->pinginterval;
- goto end;
- } else if(n->mtuprobes == 32) {
- timeout = mesh->pingtimeout;
- }
-
- for(int i = 0; i < 4 + mesh->localdiscovery; i++) {
- int len;
-
- if(i == 0) {
- if(n->mtuprobes < 30 || n->maxmtu + 8 >= MTU) {
- continue;
- }
-
- len = n->maxmtu + 8;
- } else 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;
- packet.probe = true;
- memset(packet.data, 0, 14);
- randomize(packet.data + 14, len - 14);
- packet.len = len;
- n->status.broadcast = i >= 4 && n->mtuprobes <= 10 && n->prevedge;
-
- logger(mesh, MESHLINK_DEBUG, "Sending MTU probe length %d to %s", len, n->name);
-
- send_udppacket(mesh, n, &packet);
- }
-
- n->status.broadcast = false;
-
-end:
- 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
- });
- 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_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 */
-
- packet->data[0] = 1;
-
- /* Temporarily set udp_confirmed, so that the reply is sent
- back exactly the way it came in. */
-
- bool udp_confirmed = n->status.udp_confirmed;
- n->status.udp_confirmed = true;
- send_udppacket(mesh, n, packet);
- n->status.udp_confirmed = udp_confirmed;
- } else {
- /* It's a valid reply: now we know bidirectional communication
- is possible using the address and socket that the reply
- packet used. */
-
- n->status.udp_confirmed = true;
-
- /* 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 detected, restarting PMTU discovery", n->name);
- n->maxmtu = MTU;
- n->mtuprobes = 10;
- return;
- }
-
- if(n->minmtu) {
- n->mtuprobes = 30;
- } else {
- n->mtuprobes = 1;
- }
- }
-
- /* If applicable, raise the minimum supported MTU */
-
- if(len > n->maxmtu) {
- len = n->maxmtu;
- }
-
- if(n->minmtu < len) {
- n->minmtu = len;
- }
- }
-}
-
-/* VPN packet I/O */
+/* 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", 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;
-
route(mesh, n, packet);
}
}
}
static void receive_udppacket(meshlink_handle_t *mesh, node_t *n, vpn_packet_t *inpkt) {
+ if(!n->status.reachable) {
+ logger(mesh, MESHLINK_ERROR, "Got SPTPS data from unreachable node %s", n->name);
+ return;
+ }
+
if(!n->sptps.state) {
if(!n->status.waitingforkey) {
logger(mesh, MESHLINK_DEBUG, "Got packet from %s but we haven't exchanged keys yet", n->name);
return;
}
- sptps_receive_data(&n->sptps, inpkt->data, inpkt->len);
+ if(!sptps_receive_data(&n->sptps, inpkt->data, inpkt->len)) {
+ logger(mesh, MESHLINK_ERROR, "Could not process SPTPS data from %s: %s", n->name, strerror(errno));
+ }
}
static void send_sptps_packet(meshlink_handle_t *mesh, node_t *n, vpn_packet_t *origpkt) {
+ if(!n->status.reachable) {
+ logger(mesh, MESHLINK_ERROR, "Trying to send SPTPS data to unreachable node %s", n->name);
+ return;
+ }
+
if(!n->status.validkey) {
+ if(n->connection && (n->connection->flags & PROTOCOL_TINY) & n->connection->status.active) {
+ send_raw_packet(mesh, n->connection, origpkt);
+ return;
+ }
+
logger(mesh, MESHLINK_INFO, "No valid key known yet for %s", n->name);
if(!n->status.waitingforkey) {
return;
}
- if(n->outcompression) {
- logger(mesh, MESHLINK_ERROR, "Error while compressing packet to %s", n->name);
- return;
- }
-
sptps_send_record(&n->sptps, type, origpkt->data, origpkt->len);
return;
}
-static void choose_udp_address(meshlink_handle_t *mesh, const node_t *n, const sockaddr_t **sa, int *sock) {
+void choose_udp_address(meshlink_handle_t *mesh, const node_t *n, const sockaddr_t **sa, int *sock, sockaddr_t *sa_buf) {
/* Latest guess */
*sa = &n->address;
*sock = n->sock;
to the node's reflexive UDP address discovered during key
exchange. */
- static int x = 0;
-
- if(++x >= 3) {
- x = 0;
+ if(++mesh->udp_choice >= 3) {
+ mesh->udp_choice = 0;
return;
}
+ /* If we have learned an address via Catta, try this once every batch */
+ if(mesh->udp_choice == 1 && n->catta_address.sa.sa_family != AF_UNSPEC) {
+ *sa = &n->catta_address;
+ goto check_socket;
+ }
+
+ /* Else, if we have a canonical address, try this once every batch */
+ if(mesh->udp_choice == 1 && n->canonical_address) {
+ char *host = xstrdup(n->canonical_address);
+ char *port = strchr(host, ' ');
+
+ if(port) {
+ *port++ = 0;
+ *sa_buf = str2sockaddr_random(mesh, host, port);
+ *sa = sa_buf;
+
+ if(sa_buf->sa.sa_family != AF_UNKNOWN) {
+ free(host);
+ goto check_socket;
+ }
+ }
+
+ free(host);
+ }
+
/* Otherwise, address are found in edges to this node.
So we pick a random edge and a random socket. */
- int i = 0;
- int j = rand() % n->edge_tree->count;
edge_t *candidate = NULL;
- for splay_each(edge_t, e, n->edge_tree) {
- if(i++ == j) {
- candidate = e->reverse;
- break;
+ {
+ int i = 0;
+ int j = prng(mesh, n->edge_tree->count);
+
+ for splay_each(edge_t, e, n->edge_tree) {
+ if(i++ == j) {
+ candidate = e->reverse;
+ break;
+ }
}
}
if(candidate) {
*sa = &candidate->address;
- *sock = rand() % mesh->listen_sockets;
+ *sock = prng(mesh, mesh->listen_sockets);
}
+check_socket:
+
/* Make sure we have a suitable socket for the chosen address */
if(mesh->listen_socket[*sock].sa.sa.sa_family != (*sa)->sa.sa_family) {
for(int i = 0; i < mesh->listen_sockets; i++) {
}
static void choose_broadcast_address(meshlink_handle_t *mesh, const node_t *n, const sockaddr_t **sa, int *sock) {
- static sockaddr_t broadcast_ipv4 = {
- .in = {
- .sin_family = AF_INET,
- .sin_addr.s_addr = -1,
- }
- };
-
- static sockaddr_t broadcast_ipv6 = {
- .in6 = {
- .sin6_family = AF_INET6,
- .sin6_addr.s6_addr[0x0] = 0xff,
- .sin6_addr.s6_addr[0x1] = 0x02,
- .sin6_addr.s6_addr[0xf] = 0x01,
- }
- };
+ *sock = prng(mesh, mesh->listen_sockets);
+ sockaddr_t *broadcast_sa = &mesh->listen_socket[*sock].broadcast_sa;
- *sock = rand() % mesh->listen_sockets;
-
- if(mesh->listen_socket[*sock].sa.sa.sa_family == AF_INET6) {
- if(mesh->localdiscovery_address.sa.sa_family == AF_INET6) {
- mesh->localdiscovery_address.in6.sin6_port = n->prevedge->address.in.sin_port;
- *sa = &mesh->localdiscovery_address;
- } else {
- broadcast_ipv6.in6.sin6_port = n->prevedge->address.in.sin_port;
- broadcast_ipv6.in6.sin6_scope_id = mesh->listen_socket[*sock].sa.in6.sin6_scope_id;
- *sa = &broadcast_ipv6;
- }
+ if(broadcast_sa->sa.sa_family == AF_INET6) {
+ broadcast_sa->in6.sin6_port = n->prevedge->address.in.sin_port;
} else {
- if(mesh->localdiscovery_address.sa.sa_family == AF_INET) {
- mesh->localdiscovery_address.in.sin_port = n->prevedge->address.in.sin_port;
- *sa = &mesh->localdiscovery_address;
- } else {
- broadcast_ipv4.in.sin_port = n->prevedge->address.in.sin_port;
- *sa = &broadcast_ipv4;
- }
+ broadcast_sa->in.sin_port = n->prevedge->address.in.sin_port;
}
+
+ *sa = broadcast_sa;
}
-static void send_udppacket(meshlink_handle_t *mesh, node_t *n, vpn_packet_t *origpkt) {
+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", n->name);
return;
}
bool send_sptps_data(void *handle, uint8_t type, const void *data, size_t len) {
+ assert(handle);
+ assert(data);
+ assert(len);
+
node_t *to = handle;
meshlink_handle_t *mesh = to->mesh;
+ if(!to->status.reachable) {
+ logger(mesh, MESHLINK_ERROR, "Trying to send SPTPS data to unreachable node %s", to->name);
+ return false;
+ }
+
/* Send it via TCP if it is a handshake packet, TCPOnly is in use, or this packet is larger than the MTU. */
- if(type >= SPTPS_HANDSHAKE || ((mesh->self->options | to->options) & OPTION_TCPONLY) || (type != PKT_PROBE && len > to->minmtu)) {
+ if(type >= SPTPS_HANDSHAKE || (type != PKT_PROBE && (len - 21) > to->minmtu)) {
char buf[len * 4 / 3 + 5];
b64encode(data, buf, len);
+ if(!to->nexthop || !to->nexthop->connection) {
+ logger(mesh, MESHLINK_WARNING, "Unable to forward SPTPS packet to %s via %s", to->name, to->nexthop ? to->nexthop->name : to->name);
+ return false;
+ }
+
/* 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) {
- to->incompression = mesh->self->incompression;
- return send_request(mesh, to->nexthop->connection, "%d %s %s %s -1 -1 -1 %d", ANS_KEY, mesh->self->name, to->name, buf, to->incompression);
+ return send_request(mesh, to->nexthop->connection, NULL, "%d %s %s %s -1 -1 -1 %d", ANS_KEY, mesh->self->name, to->name, buf, 0);
} else {
- return send_request(mesh, to->nexthop->connection, "%d %s %s %d %s", REQ_KEY, mesh->self->name, to->name, REQ_SPTPS, buf);
+ return send_request(mesh, to->nexthop->connection, NULL, "%d %s %s %d %s", REQ_KEY, mesh->self->name, to->name, REQ_SPTPS, buf);
}
}
/* Otherwise, send the packet via UDP */
+ sockaddr_t sa_buf;
const sockaddr_t *sa;
int sock;
if(to->status.broadcast) {
choose_broadcast_address(mesh, to, &sa, &sock);
} else {
- choose_udp_address(mesh, to, &sa, &sock);
+ choose_udp_address(mesh, to, &sa, &sock, &sa_buf);
}
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) {
- to->maxmtu = len - 1;
+ if(sockmsgsize(sockerrno) && len > 21) {
+ if(to->maxmtu >= len - 21) {
+ to->maxmtu = len - 22;
}
- if(to->mtu >= len) {
- to->mtu = len - 1;
+ if(to->mtu >= len - 21) {
+ to->mtu = len - 22;
}
} else {
logger(mesh, MESHLINK_WARNING, "Error sending UDP SPTPS packet to %s: %s", to->name, sockstrerror(sockerrno));
}
bool receive_sptps_record(void *handle, uint8_t type, const void *data, uint16_t len) {
+ assert(handle);
+ assert(!data || len);
+
node_t *from = handle;
meshlink_handle_t *mesh = from->mesh;
if(type == SPTPS_HANDSHAKE) {
if(!from->status.validkey) {
- logger(mesh, MESHLINK_INFO, "SPTPS key exchange with %s succesful", from->name);
+ logger(mesh, MESHLINK_INFO, "SPTPS key exchange with %s successful", from->name);
from->status.validkey = true;
from->status.waitingforkey = false;
return true;
}
- if(len > MTU) {
- logger(mesh, MESHLINK_ERROR, "Packet from %s larger than maximum supported size (%d > %d)", from->name, len, MTU);
+ if(len > MAXSIZE) {
+ logger(mesh, MESHLINK_ERROR, "Packet from %s larger than maximum supported size (%d > %d)", from->name, len, MAXSIZE);
return false;
}
inpkt.len = len;
inpkt.probe = true;
memcpy(inpkt.data, data, len);
- mtu_probe_h(mesh, from, &inpkt, len);
+ udp_probe_h(mesh, from, &inpkt, len);
return true;
} else {
inpkt.probe = false;
*/
void send_packet(meshlink_handle_t *mesh, node_t *n, vpn_packet_t *packet) {
if(n == mesh->self) {
- n->out_packets++;
- n->out_bytes += packet->len;
// TODO: send to application
return;
}
return;
}
- n->out_packets++;
- n->out_bytes += packet->len;
+ n->status.want_udp = true;
send_sptps_packet(mesh, n, packet);
+ keepalive(mesh, n, true);
return;
}
-/* Broadcast a packet using the minimum spanning tree */
-
-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) {
- send_packet(mesh, mesh->self, packet);
- }
-
- 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) {
- send_packet(mesh, c->node, packet);
- }
-}
-
static node_t *try_harder(meshlink_handle_t *mesh, const sockaddr_t *from, const vpn_packet_t *pkt) {
node_t *n = NULL;
bool hard = false;
- 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(sockaddrcmp_noport(from, &e->address)) {
- if(last_hard_try == mesh->loop.now.tv_sec) {
+ if(mesh->last_hard_try == mesh->loop.now.tv_sec) {
continue;
}
}
if(hard) {
- last_hard_try = mesh->loop.now.tv_sec;
+ mesh->last_hard_try = mesh->loop.now.tv_sec;
}
- last_hard_try = mesh->loop.now.tv_sec;
return n;
}
listen_socket_t *ls = data;
vpn_packet_t pkt;
char *hostname;
- sockaddr_t from = {0};
+ sockaddr_t from;
socklen_t fromlen = sizeof(from);
node_t *n;
int len;
+ memset(&from, 0, sizeof(from));
+
len = recvfrom(ls->udp.fd, pkt.data, MAXSIZE, 0, &from.sa, &fromlen);
if(len <= 0 || len > MAXSIZE) {
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);