/*
protocol_key.c -- handle the meta-protocol, key exchange
- 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 "utils.h"
#include "xalloc.h"
-void send_key_changed(meshlink_handle_t *mesh) {
- send_request(mesh, mesh->everyone, "%d %x %s", KEY_CHANGED, rand(), mesh->self->name);
-
- /* Force key exchange for connections using SPTPS */
-
- for splay_each(node_t, n, mesh->nodes)
- if(n->status.reachable && n->status.validkey)
- sptps_force_kex(&n->sptps);
-}
+static const int req_key_timeout = 2;
bool key_changed_h(meshlink_handle_t *mesh, connection_t *c, const char *request) {
+ assert(request);
+ assert(*request);
+
char name[MAX_STRING_SIZE];
node_t *n;
if(sscanf(request, "%*d %*x " MAX_STRING, name) != 1) {
- logger(mesh, MESHLINK_ERROR, "Got bad %s from %s (%s)", "KEY_CHANGED",
- c->name, c->hostname);
+ logger(mesh, MESHLINK_ERROR, "Got bad %s from %s", "KEY_CHANGED", c->name);
return false;
}
- if(seen_request(mesh, request))
+ if(seen_request(mesh, request)) {
return true;
+ }
n = lookup_node(mesh, name);
if(!n) {
- logger(mesh, MESHLINK_ERROR, "Got %s from %s (%s) origin %s which does not exist",
- "KEY_CHANGED", c->name, c->hostname, name);
+ logger(mesh, MESHLINK_ERROR, "Got %s from %s origin %s which does not exist", "KEY_CHANGED", c->name, name);
return true;
}
/* Tell the others */
- forward_request(mesh, c, request);
+ forward_request(mesh, c, NULL, request);
return true;
}
static bool send_initial_sptps_data(void *handle, uint8_t type, const void *data, size_t len) {
+ (void)type;
+
+ assert(data);
+ assert(len);
+
node_t *to = handle;
meshlink_handle_t *mesh = to->mesh;
to->sptps.send_data = send_sptps_data;
char buf[len * 4 / 3 + 5];
b64encode(data, buf, len);
- return send_request(mesh, to->nexthop->connection, "%d %s %s %d %s", REQ_KEY, mesh->self->name, to->name, REQ_KEY, buf);
+ return send_request(mesh, to->nexthop->connection, NULL, "%d %s %s %d %s", REQ_KEY, mesh->self->name, to->name, REQ_KEY, buf);
}
bool send_req_key(meshlink_handle_t *mesh, node_t *to) {
- if(!node_read_ecdsa_public_key(mesh, to)) {
- logger(mesh, MESHLINK_DEBUG, "No ECDSA key known for %s (%s)", to->name, to->hostname);
- send_request(mesh, to->nexthop->connection, "%d %s %s %d", REQ_KEY, mesh->self->name, to->name, REQ_PUBKEY);
+ if(!node_read_public_key(mesh, to)) {
+ logger(mesh, MESHLINK_DEBUG, "No ECDSA key known for %s", to->name);
+ send_request(mesh, to->nexthop->connection, NULL, "%d %s %s %d", REQ_KEY, mesh->self->name, to->name, REQ_PUBKEY);
return true;
}
- if(to->sptps.label)
+ if(to->sptps.label) {
logger(mesh, MESHLINK_DEBUG, "send_req_key(%s) called while sptps->label != NULL!", to->name);
+ }
- char label[14 + strlen(mesh->self->name) + strlen(to->name) + 1];
- snprintf(label, sizeof label, "MeshLink UDP %s %s", mesh->self->name, to->name);
+ char label[sizeof(meshlink_udp_label) + strlen(mesh->self->name) + strlen(to->name) + 2];
+ snprintf(label, sizeof(label), "%s %s %s", meshlink_udp_label, mesh->self->name, to->name);
sptps_stop(&to->sptps);
to->status.validkey = false;
to->status.waitingforkey = true;
to->last_req_key = mesh->loop.now.tv_sec;
- to->incompression = mesh->self->incompression;
- return sptps_start(&to->sptps, to, true, true, mesh->self->connection->ecdsa, to->ecdsa, label, sizeof label - 1, send_initial_sptps_data, receive_sptps_record);
+ return sptps_start(&to->sptps, to, true, true, mesh->private_key, to->ecdsa, label, sizeof(label) - 1, send_initial_sptps_data, receive_sptps_record);
}
/* REQ_KEY is overloaded to allow arbitrary requests to be routed between two nodes. */
static bool req_key_ext_h(meshlink_handle_t *mesh, connection_t *c, const char *request, node_t *from, int reqno) {
+ (void)c;
+
switch(reqno) {
- case REQ_PUBKEY: {
- char *pubkey = ecdsa_get_base64_public_key(mesh->self->connection->ecdsa);
- send_request(mesh, from->nexthop->connection, "%d %s %s %d %s", REQ_KEY, mesh->self->name, from->name, ANS_PUBKEY, pubkey);
- free(pubkey);
+ case REQ_PUBKEY: {
+ char *pubkey = ecdsa_get_base64_public_key(mesh->private_key);
+
+ if(!from->nexthop || !from->nexthop->connection) {
+ return false;
+ }
+
+ send_request(mesh, from->nexthop->connection, NULL, "%d %s %s %d %s", REQ_KEY, mesh->self->name, from->name, ANS_PUBKEY, pubkey);
+ free(pubkey);
+ return true;
+ }
+
+ case ANS_PUBKEY: {
+ if(node_read_public_key(mesh, from)) {
+ logger(mesh, MESHLINK_WARNING, "Got ANS_PUBKEY from %s even though we already have his pubkey", from->name);
return true;
}
- case ANS_PUBKEY: {
- if(node_read_ecdsa_public_key(mesh, from)) {
- logger(mesh, MESHLINK_WARNING, "Got ANS_PUBKEY from %s (%s) even though we already have his pubkey", from->name, from->hostname);
- return true;
- }
+ char pubkey[MAX_STRING_SIZE];
- char pubkey[MAX_STRING_SIZE];
- if(sscanf(request, "%*d %*s %*s %*d " MAX_STRING, pubkey) != 1 || !(from->ecdsa = ecdsa_set_base64_public_key(pubkey))) {
- logger(mesh, MESHLINK_ERROR, "Got bad %s from %s (%s): %s", "ANS_PUBKEY", from->name, from->hostname, "invalid pubkey");
- return true;
+ if(sscanf(request, "%*d %*s %*s %*d " MAX_STRING, pubkey) != 1 || !(from->ecdsa = ecdsa_set_base64_public_key(pubkey))) {
+ logger(mesh, MESHLINK_ERROR, "Got bad %s from %s: %s", "ANS_PUBKEY", from->name, "invalid pubkey");
+ return true;
+ }
+
+ logger(mesh, MESHLINK_INFO, "Learned ECDSA public key from %s", from->name);
+ from->status.dirty = true;
+
+ /* If we are trying to form an outgoing connection to this node, retry immediately */
+ for list_each(outgoing_t, outgoing, mesh->outgoings) {
+ if(outgoing->node == from && outgoing->ev.cb) {
+ outgoing->timeout = 0;
+ timeout_set(&mesh->loop, &outgoing->ev, &(struct timespec) {
+ 0, 0
+ });
}
+ }
+
+ /* Also reset any UTCP timers */
+ utcp_reset_timers(from->utcp);
+
+ return true;
+ }
- logger(mesh, MESHLINK_INFO, "Learned ECDSA public key from %s (%s)", from->name, from->hostname);
- append_config_file(mesh, from->name, "ECDSAPublicKey", pubkey);
+ case REQ_KEY: {
+ if(!node_read_public_key(mesh, from)) {
+ logger(mesh, MESHLINK_DEBUG, "No ECDSA key known for %s", from->name);
+ send_request(mesh, from->nexthop->connection, NULL, "%d %s %s %d", REQ_KEY, mesh->self->name, from->name, REQ_PUBKEY);
return true;
}
- case REQ_KEY: {
- if(!node_read_ecdsa_public_key(mesh, from)) {
- logger(mesh, MESHLINK_DEBUG, "No ECDSA key known for %s (%s)", from->name, from->hostname);
- send_request(mesh, from->nexthop->connection, "%d %s %s %d", REQ_KEY, mesh->self->name, from->name, REQ_PUBKEY);
+ if(from->sptps.label) {
+ logger(mesh, MESHLINK_DEBUG, "Got REQ_KEY from %s while we already started a SPTPS session!", from->name);
+
+ if(mesh->loop.now.tv_sec < from->last_req_key + req_key_timeout && strcmp(mesh->self->name, from->name) < 0) {
+ logger(mesh, MESHLINK_DEBUG, "Ignoring REQ_KEY from %s.", from->name);
return true;
}
+ }
- if(from->sptps.label) {
- logger(mesh, MESHLINK_DEBUG, "Got REQ_KEY from %s while we already started a SPTPS session!", from->name);
- if(strcmp(mesh->self->name, from->name) < 0) {
- logger(mesh, MESHLINK_DEBUG, "Ignoring REQ_KEY from %s.", from->name);
- return true;
- }
- }
+ char buf[MAX_STRING_SIZE];
+ int len;
- char buf[MAX_STRING_SIZE];
- int len;
+ if(sscanf(request, "%*d %*s %*s %*d " MAX_STRING, buf) != 1 || !(len = b64decode(buf, buf, strlen(buf)))) {
+ logger(mesh, MESHLINK_ERROR, "Got bad %s from %s: %s", "REQ_SPTPS_START", from->name, "invalid SPTPS data");
+ return true;
+ }
- if(sscanf(request, "%*d %*s %*s %*d " MAX_STRING, buf) != 1 || !(len = b64decode(buf, buf, strlen(buf)))) {
- logger(mesh, MESHLINK_ERROR, "Got bad %s from %s (%s): %s", "REQ_SPTPS_START", from->name, from->hostname, "invalid SPTPS data");
- return true;
- }
+ char label[sizeof(meshlink_udp_label) + strlen(from->name) + strlen(mesh->self->name) + 2];
+ snprintf(label, sizeof(label), "%s %s %s", meshlink_udp_label, from->name, mesh->self->name);
+ sptps_stop(&from->sptps);
+ from->status.validkey = false;
+ from->status.waitingforkey = true;
+ from->last_req_key = mesh->loop.now.tv_sec;
- char label[14 + strlen(from->name) + strlen(mesh->self->name) + 1];
- snprintf(label, sizeof label, "MeshLink UDP %s %s", from->name, mesh->self->name);
- sptps_stop(&from->sptps);
- from->status.validkey = false;
- from->status.waitingforkey = true;
- from->last_req_key = mesh->loop.now.tv_sec;
- sptps_start(&from->sptps, from, false, true, mesh->self->connection->ecdsa, from->ecdsa, label, sizeof label - 1, send_sptps_data, receive_sptps_record);
- sptps_receive_data(&from->sptps, buf, len);
+ if(!sptps_start(&from->sptps, from, false, true, mesh->private_key, from->ecdsa, label, sizeof(label) - 1, send_sptps_data, receive_sptps_record)) {
+ logger(mesh, MESHLINK_ERROR, "Could not start SPTPS session with %s: %s", from->name, strerror(errno));
return true;
}
- case REQ_SPTPS: {
- if(!from->status.validkey) {
- logger(mesh, MESHLINK_ERROR, "Got REQ_SPTPS from %s (%s) but we don't have a valid key yet", from->name, from->hostname);
- return true;
- }
+ if(!sptps_receive_data(&from->sptps, buf, len)) {
+ logger(mesh, MESHLINK_ERROR, "Could not process SPTPS data from %s: %s", from->name, strerror(errno));
+ return true;
+ }
- char buf[MAX_STRING_SIZE];
- int len;
- if(sscanf(request, "%*d %*s %*s %*d " MAX_STRING, buf) != 1 || !(len = b64decode(buf, buf, strlen(buf)))) {
- logger(mesh, MESHLINK_ERROR, "Got bad %s from %s (%s): %s", "REQ_SPTPS", from->name, from->hostname, "invalid SPTPS data");
- return true;
- }
- sptps_receive_data(&from->sptps, buf, len);
+ return true;
+ }
+
+ case REQ_SPTPS: {
+ if(!from->status.validkey) {
+ logger(mesh, MESHLINK_ERROR, "Got REQ_SPTPS from %s but we don't have a valid key yet", from->name);
return true;
}
- default:
- logger(mesh, MESHLINK_ERROR, "Unknown extended REQ_KEY request from %s (%s): %s", from->name, from->hostname, request);
+ char buf[MAX_STRING_SIZE];
+ int len;
+
+ if(sscanf(request, "%*d %*s %*s %*d " MAX_STRING, buf) != 1 || !(len = b64decode(buf, buf, strlen(buf)))) {
+ logger(mesh, MESHLINK_ERROR, "Got bad %s from %s: %s", "REQ_SPTPS", from->name, "invalid SPTPS data");
return true;
+ }
+
+ if(!sptps_receive_data(&from->sptps, buf, len)) {
+ logger(mesh, MESHLINK_ERROR, "Could not process SPTPS data from %s: %s", from->name, strerror(errno));
+ return true;
+ }
+
+ return true;
+ }
+
+ default:
+ logger(mesh, MESHLINK_ERROR, "Unknown extended REQ_KEY request from %s: %s", from->name, request);
+ return true;
}
}
bool req_key_h(meshlink_handle_t *mesh, connection_t *c, const char *request) {
+ assert(request);
+ assert(*request);
+
char from_name[MAX_STRING_SIZE];
char to_name[MAX_STRING_SIZE];
node_t *from, *to;
int reqno = 0;
if(sscanf(request, "%*d " MAX_STRING " " MAX_STRING " %d", from_name, to_name, &reqno) < 2) {
- logger(mesh, MESHLINK_ERROR, "Got bad %s from %s (%s)", "REQ_KEY", c->name,
- c->hostname);
+ logger(mesh, MESHLINK_ERROR, "Got bad %s from %s", "REQ_KEY", c->name);
return false;
}
if(!check_id(from_name) || !check_id(to_name)) {
- logger(mesh, MESHLINK_ERROR, "Got bad %s from %s (%s): %s", "REQ_KEY", c->name, c->hostname, "invalid name");
+ logger(mesh, MESHLINK_ERROR, "Got bad %s from %s: %s", "REQ_KEY", c->name, "invalid name");
return false;
}
from = lookup_node(mesh, from_name);
if(!from) {
- logger(mesh, MESHLINK_ERROR, "Got %s from %s (%s) origin %s which does not exist in our connection list",
- "REQ_KEY", c->name, c->hostname, from_name);
+ logger(mesh, MESHLINK_ERROR, "Got %s from %s origin %s which does not exist in our connection list",
+ "REQ_KEY", c->name, from_name);
return true;
}
to = lookup_node(mesh, to_name);
if(!to) {
- logger(mesh, MESHLINK_ERROR, "Got %s from %s (%s) destination %s which does not exist in our connection list",
- "REQ_KEY", c->name, c->hostname, to_name);
+ logger(mesh, MESHLINK_ERROR, "Got %s from %s destination %s which does not exist in our connection list",
+ "REQ_KEY", c->name, to_name);
return true;
}
if(to == mesh->self) { /* Yes */
/* Is this an extended REQ_KEY message? */
- if(reqno)
+ if(reqno) {
return req_key_ext_h(mesh, c, request, from, reqno);
+ }
- /* No, just send our key back */
- send_ans_key(mesh, from);
+ /* This should never happen. Ignore it, unless it came directly from the connected peer, in which case we disconnect. */
+ return from->connection != c;
} else {
if(!to->status.reachable) {
- logger(mesh, MESHLINK_WARNING, "Got %s from %s (%s) destination %s which is not reachable",
- "REQ_KEY", c->name, c->hostname, to_name);
+ logger(mesh, MESHLINK_WARNING, "Got %s from %s destination %s which is not reachable",
+ "REQ_KEY", c->name, to_name);
return true;
}
- send_request(mesh, to->nexthop->connection, "%s", request);
+ send_request(mesh, to->nexthop->connection, NULL, "%s", request);
}
return true;
}
-bool send_ans_key(meshlink_handle_t *mesh, node_t *to) {
- abort();
-}
-
bool ans_key_h(meshlink_handle_t *mesh, connection_t *c, const char *request) {
+ assert(request);
+ assert(*request);
+
char from_name[MAX_STRING_SIZE];
char to_name[MAX_STRING_SIZE];
char key[MAX_STRING_SIZE];
node_t *from, *to;
if(sscanf(request, "%*d "MAX_STRING" "MAX_STRING" "MAX_STRING" %d %d %d %d "MAX_STRING" "MAX_STRING,
- from_name, to_name, key, &cipher, &digest, &maclength,
- &compression, address, port) < 7) {
- logger(mesh, MESHLINK_ERROR, "Got bad %s from %s (%s)", "ANS_KEY", c->name,
- c->hostname);
+ from_name, to_name, key, &cipher, &digest, &maclength,
+ &compression, address, port) < 7) {
+ logger(mesh, MESHLINK_ERROR, "Got bad %s from %s", "ANS_KEY", c->name);
return false;
}
if(!check_id(from_name) || !check_id(to_name)) {
- logger(mesh, MESHLINK_ERROR, "Got bad %s from %s (%s): %s", "ANS_KEY", c->name, c->hostname, "invalid name");
+ logger(mesh, MESHLINK_ERROR, "Got bad %s from %s: %s", "ANS_KEY", c->name, "invalid name");
return false;
}
from = lookup_node(mesh, from_name);
if(!from) {
- logger(mesh, MESHLINK_ERROR, "Got %s from %s (%s) origin %s which does not exist in our connection list",
- "ANS_KEY", c->name, c->hostname, from_name);
+ logger(mesh, MESHLINK_ERROR, "Got %s from %s origin %s which does not exist in our connection list",
+ "ANS_KEY", c->name, from_name);
return true;
}
to = lookup_node(mesh, to_name);
if(!to) {
- logger(mesh, MESHLINK_ERROR, "Got %s from %s (%s) destination %s which does not exist in our connection list",
- "ANS_KEY", c->name, c->hostname, to_name);
+ logger(mesh, MESHLINK_ERROR, "Got %s from %s destination %s which does not exist in our connection list",
+ "ANS_KEY", c->name, to_name);
return true;
}
if(to != mesh->self) {
if(!to->status.reachable) {
- logger(mesh, MESHLINK_WARNING, "Got %s from %s (%s) destination %s which is not reachable",
- "ANS_KEY", c->name, c->hostname, to_name);
+ logger(mesh, MESHLINK_WARNING, "Got %s from %s destination %s which is not reachable",
+ "ANS_KEY", c->name, to_name);
return true;
}
- if(!*address && from->address.sa.sa_family != AF_UNSPEC) {
+ if(from == to) {
+ logger(mesh, MESHLINK_WARNING, "Got %s from %s from %s to %s",
+ "ANS_KEY", c->name, from_name, to_name);
+ return true;
+ }
+
+ /* Append the known UDP address of the from node, if we have a confirmed one */
+ if(!*address && from->status.udp_confirmed && from->address.sa.sa_family != AF_UNSPEC) {
char *address, *port;
logger(mesh, MESHLINK_DEBUG, "Appending reflexive UDP address to ANS_KEY from %s to %s", from->name, to->name);
sockaddr2str(&from->address, &address, &port);
- send_request(mesh, to->nexthop->connection, "%s %s %s", request, address, port);
+ send_request(mesh, to->nexthop->connection, NULL, "%s %s %s", request, address, port);
free(address);
free(port);
return true;
}
- return send_request(mesh, to->nexthop->connection, "%s", request);
+ return send_request(mesh, to->nexthop->connection, NULL, "%s", request);
}
- /* Don't use key material until every check has passed. */
- from->status.validkey = false;
+ /* Is this an ANS_KEY informing us of our own reflexive UDP address? */
+
+ if(from == mesh->self) {
+ if(*key == '.' && *address && *port) {
+ logger(mesh, MESHLINK_DEBUG, "Learned our own reflexive UDP address from %s: %s port %s", c->name, address, port);
+
+ /* Inform all other nodes we want to communicate with and which are reachable via this connection */
+ for splay_each(node_t, n, mesh->nodes) {
+ if(n->nexthop != c->node) {
+ continue;
+ }
+
+ if(n->status.udp_confirmed) {
+ continue;
+ }
+
+ if(!n->status.waitingforkey && !n->status.validkey) {
+ continue;
+ }
+
+ logger(mesh, MESHLINK_DEBUG, "Forwarding our own reflexive UDP address to %s", n->name);
+ send_request(mesh, c, NULL, "%d %s %s . -1 -1 -1 0 %s %s", ANS_KEY, mesh->self->name, n->name, address, port);
+ }
+ } else {
+ logger(mesh, MESHLINK_WARNING, "Got %s from %s from %s to %s",
+ "ANS_KEY", c->name, from_name, to_name);
+ }
- if(compression < 0 || compression > 11) {
- logger(mesh, MESHLINK_ERROR, "Node %s (%s) uses bogus compression level!", from->name, from->hostname);
return true;
}
- from->outcompression = compression;
+ /* Process SPTPS data if present */
- /* SPTPS or old-style key exchange? */
+ if(*key != '.') {
+ /* Don't use key material until every check has passed. */
+ from->status.validkey = false;
- char buf[strlen(key)];
- int len = b64decode(key, buf, strlen(key));
+ /* Compression is not supported. */
+ if(compression != 0) {
+ logger(mesh, MESHLINK_ERROR, "Node %s uses bogus compression level!", from->name);
+ return true;
+ }
+
+ char buf[strlen(key)];
+ int len = b64decode(key, buf, strlen(key));
- if(!len || !sptps_receive_data(&from->sptps, buf, len))
- logger(mesh, MESHLINK_ERROR, "Error processing SPTPS data from %s (%s)", from->name, from->hostname);
+ if(!len || !sptps_receive_data(&from->sptps, buf, len)) {
+ logger(mesh, MESHLINK_ERROR, "Error processing SPTPS data from %s", from->name);
+ }
+ }
if(from->status.validkey) {
if(*address && *port) {
update_node_udp(mesh, from, &sa);
}
- if(from->options & OPTION_PMTU_DISCOVERY && !(from->options & OPTION_TCPONLY))
- send_mtu_probe(mesh, from);
+ send_mtu_probe(mesh, from);
}
return true;
projects / meshlink / blobdiff