X-Git-Url: https://tinc-vpn.org/git/browse?a=blobdiff_plain;f=src%2Fgraph.c;h=49161c1683754a517625698055b6bd7783ff7674;hb=abb24e9d71b3edb9cacf4c04361cc0dfd4e6a061;hp=e8e8baf4a0d1aef063ec59c89144358f2fc7bdcb;hpb=04d33be4bd102de67bb6dba5c449e12fea0db4d2;p=tinc diff --git a/src/graph.c b/src/graph.c index e8e8baf4..49161c16 100644 --- a/src/graph.c +++ b/src/graph.c @@ -1,7 +1,7 @@ /* graph.c -- graph algorithms - Copyright (C) 2001-2002 Guus Sliepen , - 2001-2002 Ivo Timmermans + Copyright (C) 2001-2013 Guus Sliepen , + 2001-2005 Ivo Timmermans 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 @@ -13,11 +13,9 @@ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. - You should have received a copy of the GNU General Public License - along with this program; if not, write to the Free Software - Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. - - $Id: graph.c,v 1.4 2002/04/28 12:46:26 zarq Exp $ + You should have received a copy of the GNU General Public License along + with this program; if not, write to the Free Software Foundation, Inc., + 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. */ /* We need to generate two trees from the graph: @@ -44,247 +42,262 @@ destination address and port of a node if possible. */ -#include "config.h" - -#include -#include -#include -#if defined(HAVE_FREEBSD) || defined(HAVE_OPENBSD) - #include -#endif -#include - -#include -#include +#include "system.h" +#include "connection.h" +#include "device.h" +#include "edge.h" +#include "graph.h" +#include "list.h" +#include "logger.h" +#include "names.h" #include "netutl.h" #include "node.h" -#include "edge.h" -#include "connection.h" -#include "process.h" -#include "logging.h" - -#include "system.h" +#include "protocol.h" +#include "script.h" +#include "subnet.h" +#include "utils.h" +#include "xalloc.h" +#include "graph.h" /* Implementation of Kruskal's algorithm. Running time: O(EN) Please note that sorting on weight is already done by add_edge(). */ -void mst_kruskal(void) -{ - avl_node_t *node, *next; - edge_t *e; - node_t *n; - connection_t *c; - int nodes = 0; - int safe_edges = 0; - int skipped; - - /* Clear MST status on connections */ - - for(node = connection_tree->head; node; node = node->next) - { - c = (connection_t *)node->data; - c->status.mst = 0; - } - - /* Do we have something to do at all? */ - - if(!edge_weight_tree->head) - return; - - if(debug_lvl >= DEBUG_SCARY_THINGS) - syslog(LOG_DEBUG, "Running Kruskal's algorithm:"); - - /* Clear visited status on nodes */ - - for(node = node_tree->head; node; node = node->next) - { - n = (node_t *)node->data; - n->status.visited = 0; - nodes++; - } - - /* Starting point */ - - ((edge_t *)edge_weight_tree->head->data)->from.node->status.visited = 1; - - /* Add safe edges */ - - for(skipped = 0, node = edge_weight_tree->head; node; node = next) - { - next = node->next; - e = (edge_t *)node->data; - - if(e->from.node->status.visited == e->to.node->status.visited) - { - skipped = 1; - continue; - } - - e->from.node->status.visited = 1; - e->to.node->status.visited = 1; - if(e->connection) - e->connection->status.mst = 1; - - safe_edges++; - - if(debug_lvl >= DEBUG_SCARY_THINGS) - syslog(LOG_DEBUG, " Adding edge %s - %s weight %d", e->from.node->name, e->to.node->name, e->weight); - - if(skipped) - { - next = edge_weight_tree->head; - continue; - } - } - - if(debug_lvl >= DEBUG_SCARY_THINGS) - syslog(LOG_DEBUG, "Done, counted %d nodes and %d safe edges.", nodes, safe_edges); +static void mst_kruskal(void) { + /* Clear MST status on connections */ + + for list_each(connection_t, c, connection_list) + c->status.mst = false; + + logger(DEBUG_SCARY_THINGS, LOG_DEBUG, "Running Kruskal's algorithm:"); + + /* Clear visited status on nodes */ + + for splay_each(node_t, n, node_tree) + n->status.visited = false; + + /* Starting point */ + + for splay_each(edge_t, e, edge_weight_tree) { + if(e->from->status.reachable) { + e->from->status.visited = true; + break; + } + } + + /* Add safe edges */ + + bool skipped = false; + + for splay_each(edge_t, e, edge_weight_tree) { + if(!e->reverse || (e->from->status.visited == e->to->status.visited)) { + skipped = true; + continue; + } + + e->from->status.visited = true; + e->to->status.visited = true; + + if(e->connection) + e->connection->status.mst = true; + + if(e->reverse->connection) + e->reverse->connection->status.mst = true; + + logger(DEBUG_SCARY_THINGS, LOG_DEBUG, " Adding edge %s - %s weight %d", e->from->name, e->to->name, e->weight); + + if(skipped) { + skipped = false; + next = edge_weight_tree->head; + } + } } /* Implementation of a simple breadth-first search algorithm. Running time: O(E) */ -void sssp_bfs(void) -{ - avl_node_t *node, *from, *next, *to; - edge_t *e; - node_t *n; - halfconnection_t to_hc, from_hc; - avl_tree_t *todo_tree; - int indirect; - char *name; - - todo_tree = avl_alloc_tree(NULL, NULL); - - /* Clear visited status on nodes */ - - for(node = node_tree->head; node; node = node->next) - { - n = (node_t *)node->data; - n->status.visited = 0; - n->status.indirect = 1; - } - - /* Begin with myself */ - - myself->status.visited = 1; - myself->status.indirect = 0; - myself->nexthop = myself; - myself->via = myself; - node = avl_alloc_node(); - node->data = myself; - avl_insert_top(todo_tree, node); - - /* Loop while todo_tree is filled */ - - while(todo_tree->head) - { - for(from = todo_tree->head; from; from = next) /* "from" is the node from which we start */ - { - next = from->next; - n = (node_t *)from->data; - - for(to = n->edge_tree->head; to; to = to->next) /* "to" is the edge connected to "from" */ - { - e = (edge_t *)to->data; - - if(e->from.node == n) /* "from_hc" is the halfconnection with .node == from */ - to_hc = e->to, from_hc = e->from; - else - to_hc = e->from, from_hc = e->to; - - /* Situation: - - / - / - ------(n)from_hc-----to_hc - \ - \ - - n->address is set to the to_hc.udpaddress of the edge left of n. - We are currently examining the edge right of n: - - - If from_hc.udpaddress != n->address, then to_hc.node is probably - not reachable for the nodes left of n. We do as if the indirectdata - flag is set on edge e. - - If edge e provides for better reachability of to_hc.node, update - to_hc.node and (re)add it to the todo_tree to (re)examine the reachability - of nodes behind it. - */ - - indirect = n->status.indirect || e->options & OPTION_INDIRECT || ((n != myself) && sockaddrcmp(&n->address, &from_hc.udpaddress)); - - if(to_hc.node->status.visited && (!to_hc.node->status.indirect || indirect)) - continue; - - to_hc.node->status.visited = 1; - to_hc.node->status.indirect = indirect; - to_hc.node->nexthop = (n->nexthop == myself) ? to_hc.node : n->nexthop; - to_hc.node->via = indirect ? n->via : to_hc.node; - to_hc.node->options = e->options; - if(sockaddrcmp(&to_hc.node->address, &to_hc.udpaddress)) - { - node = avl_unlink(node_udp_tree, to_hc.node); - to_hc.node->address = to_hc.udpaddress; - if(to_hc.node->hostname) - free(to_hc.node->hostname); - to_hc.node->hostname = sockaddr2hostname(&to_hc.udpaddress); - avl_insert_node(node_udp_tree, node); - } - node = avl_alloc_node(); - node->data = to_hc.node; - avl_insert_before(todo_tree, from, node); - } - - avl_delete_node(todo_tree, from); - } - } - - avl_free_tree(todo_tree); - - /* Check reachability status. */ - - for(node = node_tree->head; node; node = next) - { - next = node->next; - n = (node_t *)node->data; - - if(n->status.visited) - { - if(!n->status.reachable) - { - if(debug_lvl >= DEBUG_TRAFFIC) - syslog(LOG_DEBUG, _("Node %s (%s) became reachable"), n->name, n->hostname); - n->status.reachable = 1; - asprintf(&name, "hosts/%s-up", n->name); - execute_script(name); - free(name); +static void sssp_bfs(void) { + list_t *todo_list = list_alloc(NULL); + + /* Clear visited status on nodes */ + + for splay_each(node_t, n, node_tree) { + n->status.visited = false; + n->status.indirect = true; + n->distance = -1; + } + + /* Begin with myself */ + + myself->status.visited = true; + myself->status.indirect = false; + myself->nexthop = myself; + myself->prevedge = NULL; + myself->via = myself; + myself->distance = 0; + list_insert_head(todo_list, myself); + + /* Loop while todo_list is filled */ + + for list_each(node_t, n, todo_list) { /* "n" is the node from which we start */ + logger(DEBUG_SCARY_THINGS, LOG_DEBUG, " Examining edges from %s", n->name); + + if(n->distance < 0) + abort(); + + for splay_each(edge_t, e, n->edge_tree) { /* "e" is the edge connected to "from" */ + if(!e->reverse) + continue; + + /* Situation: + + / + / + ----->(n)---e-->(e->to) + \ + \ + + Where e is an edge, (n) and (e->to) are nodes. + n->address is set to the e->address of the edge left of n to n. + We are currently examining the edge e right of n from n: + + - If edge e provides for better reachability of e->to, update + e->to and (re)add it to the todo_list to (re)examine the reachability + of nodes behind it. + */ + + bool indirect = n->status.indirect || e->options & OPTION_INDIRECT; + + if(e->to->status.visited + && (!e->to->status.indirect || indirect) + && (e->to->distance != n->distance + 1 || e->weight >= e->to->prevedge->weight)) + continue; + + // Only update nexthop if it doesn't increase the path length + + if(!e->to->status.visited || (e->to->distance == n->distance + 1 && e->weight >= e->to->prevedge->weight)) + e->to->nexthop = (n->nexthop == myself) ? e->to : n->nexthop; + + e->to->status.visited = true; + e->to->status.indirect = indirect; + e->to->prevedge = e; + e->to->via = indirect ? n->via : e->to; + e->to->options = e->options; + e->to->distance = n->distance + 1; + + if(!e->to->status.reachable || (e->to->address.sa.sa_family == AF_UNSPEC && e->address.sa.sa_family != AF_UNKNOWN)) + update_node_udp(e->to, &e->address); + + list_insert_tail(todo_list, e->to); + } + + next = node->next; /* Because the list_insert_tail() above could have added something extra for us! */ + list_delete_node(todo_list, node); + } + + list_free(todo_list); +} + +static void check_reachability(void) { + /* Check reachability status. */ + + int reachable_count = 0; + int became_reachable_count = 0; + int became_unreachable_count = 0; + for splay_each(node_t, n, node_tree) { + if(n->status.visited != n->status.reachable) { + n->status.reachable = !n->status.reachable; + n->last_state_change = now.tv_sec; + + if(n->status.reachable) { + logger(DEBUG_TRAFFIC, LOG_DEBUG, "Node %s (%s) became reachable", + n->name, n->hostname); + if (n != myself) + became_reachable_count++; + } else { + logger(DEBUG_TRAFFIC, LOG_DEBUG, "Node %s (%s) became unreachable", + n->name, n->hostname); + if (n != myself) + became_unreachable_count++; + } + + if(experimental && OPTION_VERSION(n->options) >= 2) + n->status.sptps = true; + + /* TODO: only clear status.validkey if node is unreachable? */ + + n->status.validkey = false; + if(n->status.sptps) { + sptps_stop(&n->sptps); + n->status.waitingforkey = false; + } + n->last_req_key = 0; + + n->status.udp_confirmed = false; + n->maxmtu = MTU; + n->maxrecentlen = 0; + n->minmtu = 0; + n->mtuprobes = 0; + + timeout_del(&n->udp_ping_timeout); + + char *name; + char *address; + char *port; + char *envp[8] = {NULL}; + + xasprintf(&envp[0], "NETNAME=%s", netname ? : ""); + xasprintf(&envp[1], "DEVICE=%s", device ? : ""); + xasprintf(&envp[2], "INTERFACE=%s", iface ? : ""); + xasprintf(&envp[3], "NODE=%s", n->name); + sockaddr2str(&n->address, &address, &port); + xasprintf(&envp[4], "REMOTEADDRESS=%s", address); + xasprintf(&envp[5], "REMOTEPORT=%s", port); + xasprintf(&envp[6], "NAME=%s", myself->name); + + execute_script(n->status.reachable ? "host-up" : "host-down", envp); + + xasprintf(&name, n->status.reachable ? "hosts/%s-up" : "hosts/%s-down", n->name); + execute_script(name, envp); + + free(name); + free(address); + free(port); + + for(int i = 0; i < 7; i++) + free(envp[i]); + + subnet_update(n, NULL, n->status.reachable); + + if(!n->status.reachable) { + update_node_udp(n, NULL); + memset(&n->status, 0, sizeof n->status); + n->options = 0; + } else if(n->connection) { + // Speed up UDP probing by sending our key. + if(!n->status.sptps) + send_ans_key(n); + } + } + + if(n->status.reachable && n != myself) + reachable_count++; } - } - else - { - if(n->status.reachable) - { - if(debug_lvl >= DEBUG_TRAFFIC) - syslog(LOG_DEBUG, _("Node %s (%s) became unreachable"), n->name, n->hostname); - n->status.reachable = 0; - n->status.validkey = 0; - n->status.waitingforkey = 0; - n->sent_seqno = 0; - asprintf(&name, "hosts/%s-down", n->name); - execute_script(name); - free(name); + + if (device_standby) { + if (reachable_count == 0 && became_unreachable_count > 0) + device_disable(); + else if (reachable_count > 0 && reachable_count == became_reachable_count) + device_enable(); } - } - } } -void graph(void) -{ - mst_kruskal(); - sssp_bfs(); +void graph(void) { + subnet_cache_flush(); + sssp_bfs(); + check_reachability(); + mst_kruskal(); }