#include "utils.h"
#include "xalloc.h"
+#ifndef MIN
+#define MIN(x, y) (((x)<(y))?(x):(y))
+#endif
+
int maxoutbufsize = 0;
+int mtu_info_interval = 5;
+int udp_info_interval = 5;
/* Status and error notification routines */
return true;
}
+bool send_sptps_tcppacket(connection_t *c, const char* packet, int len) {
+ /* If there already is a lot of data in the outbuf buffer, discard this packet.
+ We use a very simple Random Early Drop algorithm. */
+
+ if(2.0 * c->outbuf.len / (float)maxoutbufsize - 1 > (float)rand()/(float)RAND_MAX)
+ return true;
+
+ if(!send_request(c, "%d %d", SPTPS_PACKET, len))
+ return false;
+
+ send_meta_raw(c, packet, len);
+ return true;
+}
+
+bool sptps_tcppacket_h(connection_t *c, const char* request) {
+ short int len;
+
+ if(sscanf(request, "%*d %hd", &len) != 1) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Got bad %s from %s (%s)", "SPTPS_PACKET", c->name,
+ c->hostname);
+ return false;
+ }
+
+ /* Set sptpslen to len, this will tell receive_meta() that a SPTPS packet is coming. */
+
+ c->sptpslen = len;
+
+ return true;
+}
+
/* Transmitting UDP information */
bool send_udp_info(node_t *from, node_t *to) {
if(!to->status.reachable)
return true;
- if(from == myself && to->connection)
- return true;
+ if(from == myself) {
+ if(to->connection)
+ return true;
+
+ struct timeval elapsed;
+ timersub(&now, &to->udp_info_sent, &elapsed);
+ if(elapsed.tv_sec < udp_info_interval)
+ return true;
+ }
if((myself->options | from->options | to->options) & OPTION_TCPONLY)
return true;
free(from_address);
free(from_port);
+ if(from == myself)
+ to->udp_info_sent = now;
+
return x;
}
return send_udp_info(from, to);
}
+
+/* Transmitting MTU information */
+
+bool send_mtu_info(node_t *from, node_t *to, int mtu) {
+ /* Skip cases where sending MTU info messages doesn't make sense.
+ This is done here in order to avoid repeating the same logic in multiple callsites. */
+
+ if(to == myself)
+ return true;
+
+ if(!to->status.reachable)
+ return true;
+
+ if(from == myself) {
+ if(to->connection)
+ return true;
+
+ struct timeval elapsed;
+ timersub(&now, &to->mtu_info_sent, &elapsed);
+ if(elapsed.tv_sec < mtu_info_interval)
+ return true;
+ }
+
+ if((to->nexthop->options >> 24) < 6)
+ return true;
+
+ /* We will send the passed-in MTU value, unless we believe ours is better. */
+
+ node_t *via = (from->via == myself) ? from->nexthop : from->via;
+ if(from->minmtu == from->maxmtu && from->via == myself) {
+ /* We have a direct measurement. Override the value entirely.
+ Note that we only do that if we are sitting as a static relay in the path;
+ otherwise, we can't guarantee packets will flow through us, and increasing
+ MTU could therefore end up being too optimistic. */
+ mtu = from->minmtu;
+ } else if(via->minmtu == via->maxmtu) {
+ /* Static relay. Ensure packets will make it through the entire relay path. */
+ mtu = MIN(mtu, via->minmtu);
+ } else if(via->nexthop->minmtu == via->nexthop->maxmtu) {
+ /* Dynamic relay. Ensure packets will make it through the entire relay path. */
+ mtu = MIN(mtu, via->nexthop->minmtu);
+ }
+
+ if(from == myself)
+ to->mtu_info_sent = now;
+
+ /* If none of the conditions above match in the steady state, it means we're using TCP,
+ so the MTU is irrelevant. That said, it is still important to honor the MTU that was passed in,
+ because other parts of the relay path might be able to use UDP, which means they care about the MTU. */
+
+ return send_request(to->nexthop->connection, "%d %s %s %d", MTU_INFO, from->name, to->name, mtu);
+}
+
+bool mtu_info_h(connection_t *c, const char* request) {
+ char from_name[MAX_STRING_SIZE];
+ char to_name[MAX_STRING_SIZE];
+ int mtu;
+
+ if(sscanf(request, "%*d "MAX_STRING" "MAX_STRING" %d", from_name, to_name, &mtu) != 3) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Got bad %s from %s (%s)", "MTU_INFO", c->name, c->hostname);
+ return false;
+ }
+
+ if(mtu < 512) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Got bad %s from %s (%s): %s", "MTU_INFO", c->name, c->hostname, "invalid MTU");
+ return false;
+ }
+
+ mtu = MIN(mtu, MTU);
+
+ if(!check_id(from_name) || !check_id(to_name)) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Got bad %s from %s (%s): %s", "MTU_INFO", c->name, c->hostname, "invalid name");
+ return false;
+ }
+
+ node_t *from = lookup_node(from_name);
+ if(!from) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Got %s from %s (%s) origin %s which does not exist in our connection list", "MTU_INFO", c->name, c->hostname, from_name);
+ return true;
+ }
+
+ /* If we don't know the current MTU for that node, use the one we received.
+ Even if we're about to make our own measurements, the value we got from downstream nodes should be pretty close
+ so it's a good idea to use it in the mean time. */
+ if(from->mtu != mtu && from->minmtu != from->maxmtu) {
+ logger(DEBUG_TRAFFIC, LOG_INFO, "Using provisional MTU %d for node %s (%s)", mtu, from->name, from->hostname);
+ from->mtu = mtu;
+ }
+
+ node_t *to = lookup_node(to_name);
+ if(!to) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Got %s from %s (%s) destination %s which does not exist in our connection list", "MTU_INFO", c->name, c->hostname, to_name);
+ return true;
+ }
+
+ /* Continue passing the MTU value (or a better one if we have it) up the chain. */
+
+ return send_mtu_info(from, to, mtu);
+}
projects / tinc / blobdiff