X-Git-Url: https://www.tinc-vpn.org/git/browse?a=blobdiff_plain;f=src%2Fsubnet.c;h=4fefda6ff8f47996c380eabf2165da7d72b1aa9f;hb=refs%2Fheads%2F1.1;hp=1cb816390465fda49cc0bf762ee645f05d50167a;hpb=7ea85043ac1fb2096baea44f6b0af27ac0d0b2cf;p=tinc diff --git a/src/subnet.c b/src/subnet.c index 1cb81639..94000cc0 100644 --- a/src/subnet.c +++ b/src/subnet.c @@ -1,6 +1,6 @@ /* subnet.c -- handle subnet lookups and lists - Copyright (C) 2000-2009 Guus Sliepen , + Copyright (C) 2000-2022 Guus Sliepen , 2000-2005 Ivo Timmermans This program is free software; you can redistribute it and/or modify @@ -21,488 +21,389 @@ #include "system.h" #include "splay_tree.h" -#include "device.h" +#include "control_common.h" +#include "crypto.h" +#include "hash.h" #include "logger.h" #include "net.h" #include "netutl.h" #include "node.h" -#include "process.h" +#include "script.h" #include "subnet.h" -#include "utils.h" #include "xalloc.h" +#include "sandbox.h" /* lists type of subnet */ - -splay_tree_t *subnet_tree; +uint32_t hash_seed; +splay_tree_t subnet_tree = { + .compare = (splay_compare_t) subnet_compare, + .delete = (splay_action_t) free_subnet, +}; /* Subnet lookup cache */ -static ipv4_t cache_ipv4_address[2]; -static subnet_t *cache_ipv4_subnet[2]; -static bool cache_ipv4_valid[2]; -static int cache_ipv4_slot; - -static ipv6_t cache_ipv6_address[2]; -static subnet_t *cache_ipv6_subnet[2]; -static bool cache_ipv6_valid[2]; -static int cache_ipv6_slot; - -void subnet_cache_flush() { - cache_ipv4_valid[0] = cache_ipv4_valid[1] = false; - cache_ipv6_valid[0] = cache_ipv6_valid[1] = false; +static uint32_t wrapping_add32(uint32_t a, uint32_t b) { + return (uint32_t)((uint64_t)a + b); } -/* Subnet comparison */ - -static int subnet_compare_mac(const subnet_t *a, const subnet_t *b) { - int result; - - result = memcmp(&a->net.mac.address, &b->net.mac.address, sizeof a->net.mac.address); - - if(result) - return result; - - result = a->weight - b->weight; - - if(result || !a->owner || !b->owner) - return result; - - return strcmp(a->owner->name, b->owner->name); +static uint32_t wrapping_mul32(uint32_t a, uint32_t b) { + return (uint32_t)((uint64_t)a * b); } -static int subnet_compare_ipv4(const subnet_t *a, const subnet_t *b) { - int result; - - result = b->net.ipv4.prefixlength - a->net.ipv4.prefixlength; - - if(result) - return result; +static uint32_t hash_function_ipv4_t(const ipv4_t *p) { + /* + This basic hash works because + a) Most IPv4 networks routed via tinc are not /0 + b) Most IPv4 networks have more unique low order bits + */ + uint16_t *halfwidth = (uint16_t *)p; + uint32_t hash = hash_seed; + +#if __BYTE_ORDER == __LITTLE_ENDIAN + // 10.0.x.x/16 part + hash = wrapping_add32(hash, wrapping_mul32(halfwidth[1], 0x9e370001U)); + + // x.x.0.[0-255] part +#if SUBNET_HASH_SIZE >= 0x10000 + return hash ^ halfwidth[0]; +#else + // ensure that we have a /24 with no collisions on 32bit + return hash ^ ntohs(halfwidth[0]); +#endif // _____LP64_____ +#else + // 10.0.x.x/16 part + hash = wrapping_add32(hash, wrapping_mul32(halfwidth[0], 0x9e370001U)); + + // x.x.0.[0-255] part (ntohs is nop on big endian) + return hash ^ halfwidth[1]; +#endif // __BYTE_ORDER == __LITTLE_ENDIAN +} - result = memcmp(&a->net.ipv4.address, &b->net.ipv4.address, sizeof(ipv4_t)); - if(result) - return result; - - result = a->weight - b->weight; +static uint32_t hash_function_ipv6_t(const ipv6_t *p) { + uint32_t *fullwidth = (uint32_t *)p; + uint32_t hash = hash_seed; - if(result || !a->owner || !b->owner) - return result; + for(int i = 0; i < 4; i++) { + hash = wrapping_add32(hash, fullwidth[i]); + hash = wrapping_mul32(hash, 0x9e370001U); + } - return strcmp(a->owner->name, b->owner->name); + return hash; } -static int subnet_compare_ipv6(const subnet_t *a, const subnet_t *b) { - int result; +static uint32_t hash_function_mac_t(const mac_t *p) { + uint16_t *halfwidth = (uint16_t *)p; + uint32_t hash = hash_seed; - result = b->net.ipv6.prefixlength - a->net.ipv6.prefixlength; - - if(result) - return result; - - result = memcmp(&a->net.ipv6.address, &b->net.ipv6.address, sizeof(ipv6_t)); + for(int i = 0; i < 3; i++) { + hash = wrapping_add32(hash, halfwidth[i]); + hash = wrapping_mul32(hash, 0x9e370001U); + } - if(result) - return result; - - result = a->weight - b->weight; + return hash; +} - if(result || !a->owner || !b->owner) - return result; +hash_define(ipv4_t, SUBNET_HASH_SIZE) +hash_define(ipv6_t, SUBNET_HASH_SIZE) +hash_define(mac_t, SUBNET_HASH_SIZE) - return strcmp(a->owner->name, b->owner->name); -} +hash_new(ipv4_t, ipv4_cache); +hash_new(ipv6_t, ipv6_cache); +hash_new(mac_t, mac_cache); -int subnet_compare(const subnet_t *a, const subnet_t *b) { - int result; - result = a->type - b->type; +void subnet_cache_flush_table(subnet_type_t stype) { + // NOTE: a subnet type of SUBNET_TYPES can be used to clear all hash tables - if(result) - return result; + if(stype != SUBNET_IPV6) { // ipv4 + hash_clear(ipv4_t, &ipv4_cache); + } - switch (a->type) { - case SUBNET_MAC: - return subnet_compare_mac(a, b); - case SUBNET_IPV4: - return subnet_compare_ipv4(a, b); - case SUBNET_IPV6: - return subnet_compare_ipv6(a, b); - default: - logger(LOG_ERR, "subnet_compare() was called with unknown subnet type %d, exitting!", - a->type); - exit(0); + if(stype != SUBNET_IPV4) { // ipv6 + hash_clear(ipv6_t, &ipv6_cache); } - return 0; + hash_clear(mac_t, &mac_cache); } /* Initialising trees */ void init_subnets(void) { - subnet_tree = splay_alloc_tree((splay_compare_t) subnet_compare, (splay_action_t) free_subnet); + hash_seed = prng(UINT32_MAX); - subnet_cache_flush(); + // tables need to be cleared on startup + subnet_cache_flush_tables(); } void exit_subnets(void) { - splay_delete_tree(subnet_tree); + splay_empty_tree(&subnet_tree); + subnet_cache_flush_tables(); } -splay_tree_t *new_subnet_tree(void) { - return splay_alloc_tree((splay_compare_t) subnet_compare, NULL); -} - -void free_subnet_tree(splay_tree_t *subnet_tree) { - splay_delete_tree(subnet_tree); +void init_subnet_tree(splay_tree_t *tree) { + memset(tree, 0, sizeof(*tree)); + tree->compare = (splay_compare_t) subnet_compare; } /* Allocating and freeing space for subnets */ subnet_t *new_subnet(void) { - return xmalloc_and_zero(sizeof(subnet_t)); + return xzalloc(sizeof(subnet_t)); } void free_subnet(subnet_t *subnet) { free(subnet); } -/* Adding and removing subnets */ - -void subnet_add(node_t *n, subnet_t *subnet) { - subnet->owner = n; - - splay_insert(subnet_tree, subnet); - splay_insert(n->subnet_tree, subnet); - - subnet_cache_flush(); +void subnet_cache_flush_tables(void) { + // flushes all the tables + hash_clear(ipv4_t, &ipv4_cache); + hash_clear(ipv6_t, &ipv6_cache); + hash_clear(mac_t, &mac_cache); } -void subnet_del(node_t *n, subnet_t *subnet) { - splay_delete(n->subnet_tree, subnet); - splay_delete(subnet_tree, subnet); - - subnet_cache_flush(); -} - -/* Ascii representation of subnets */ - -bool str2net(subnet_t *subnet, const char *subnetstr) { - int i, l; - uint16_t x[8]; - int weight = 10; - - if(sscanf(subnetstr, "%hu.%hu.%hu.%hu/%d#%d", - &x[0], &x[1], &x[2], &x[3], &l, &weight) >= 5) { - if(l < 0 || l > 32) - return false; +static void subnet_cache_flush(subnet_t *subnet) { + switch(subnet->type) { + case SUBNET_IPV4: + if(subnet->net.ipv4.prefixlength == 32) { + hash_delete(ipv4_t, &ipv4_cache, &subnet->net.ipv4.address); + return; + } - subnet->type = SUBNET_IPV4; - subnet->net.ipv4.prefixlength = l; - subnet->weight = weight; + break; - for(i = 0; i < 4; i++) { - if(x[i] > 255) - return false; - subnet->net.ipv4.address.x[i] = x[i]; + case SUBNET_IPV6: + if(subnet->net.ipv4.prefixlength == 128) { + hash_delete(ipv6_t, &ipv6_cache, &subnet->net.ipv6.address); + return; } - return true; - } - - if(sscanf(subnetstr, "%hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx/%d#%d", - &x[0], &x[1], &x[2], &x[3], &x[4], &x[5], &x[6], &x[7], - &l, &weight) >= 9) { - if(l < 0 || l > 128) - return false; + break; - subnet->type = SUBNET_IPV6; - subnet->net.ipv6.prefixlength = l; - subnet->weight = weight; + case SUBNET_MAC: + hash_delete(mac_t, &mac_cache, &subnet->net.mac.address); + return; + } - for(i = 0; i < 8; i++) - subnet->net.ipv6.address.x[i] = htons(x[i]); + subnet_cache_flush_table(subnet->type); +} - return true; - } +/* Adding and removing subnets */ - if(sscanf(subnetstr, "%hu.%hu.%hu.%hu#%d", &x[0], &x[1], &x[2], &x[3], &weight) >= 4) { - subnet->type = SUBNET_IPV4; - subnet->net.ipv4.prefixlength = 32; - subnet->weight = weight; +void subnet_add(node_t *n, subnet_t *subnet) { + subnet->owner = n; - for(i = 0; i < 4; i++) { - if(x[i] > 255) - return false; - subnet->net.ipv4.address.x[i] = x[i]; - } + splay_insert(&subnet_tree, subnet); - return true; + if(n) { + splay_insert(&n->subnet_tree, subnet); } - if(sscanf(subnetstr, "%hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx#%d", - &x[0], &x[1], &x[2], &x[3], &x[4], &x[5], &x[6], &x[7], &weight) >= 8) { - subnet->type = SUBNET_IPV6; - subnet->net.ipv6.prefixlength = 128; - subnet->weight = weight; - - for(i = 0; i < 8; i++) - subnet->net.ipv6.address.x[i] = htons(x[i]); + subnet_cache_flush(subnet); +} - return true; +void subnet_del(node_t *n, subnet_t *subnet) { + if(n) { + splay_delete(&n->subnet_tree, subnet); } - if(sscanf(subnetstr, "%hx:%hx:%hx:%hx:%hx:%hx#%d", - &x[0], &x[1], &x[2], &x[3], &x[4], &x[5], &weight) >= 6) { - subnet->type = SUBNET_MAC; - subnet->weight = weight; + splay_delete(&subnet_tree, subnet); - for(i = 0; i < 6; i++) - subnet->net.mac.address.x[i] = x[i]; + subnet_cache_flush(subnet); +} - return true; - } +/* Subnet lookup routines */ - return false; +subnet_t *lookup_subnet(node_t *owner, const subnet_t *subnet) { + return splay_search(&owner->subnet_tree, subnet); } -bool net2str(char *netstr, int len, const subnet_t *subnet) { - if(!netstr || !subnet) { - logger(LOG_ERR, "net2str() was called with netstr=%p, subnet=%p!\n", netstr, subnet); - return false; - } +subnet_t *lookup_subnet_mac(const node_t *owner, const mac_t *address) { + subnet_t *r = NULL; + + // Check if this address is cached - switch (subnet->type) { - case SUBNET_MAC: - snprintf(netstr, len, "%hx:%hx:%hx:%hx:%hx:%hx#%d", - subnet->net.mac.address.x[0], - subnet->net.mac.address.x[1], - subnet->net.mac.address.x[2], - subnet->net.mac.address.x[3], - subnet->net.mac.address.x[4], - subnet->net.mac.address.x[5], - subnet->weight); - break; - - case SUBNET_IPV4: - snprintf(netstr, len, "%hu.%hu.%hu.%hu/%d#%d", - subnet->net.ipv4.address.x[0], - subnet->net.ipv4.address.x[1], - subnet->net.ipv4.address.x[2], - subnet->net.ipv4.address.x[3], - subnet->net.ipv4.prefixlength, - subnet->weight); - break; - - case SUBNET_IPV6: - snprintf(netstr, len, "%hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx/%d#%d", - ntohs(subnet->net.ipv6.address.x[0]), - ntohs(subnet->net.ipv6.address.x[1]), - ntohs(subnet->net.ipv6.address.x[2]), - ntohs(subnet->net.ipv6.address.x[3]), - ntohs(subnet->net.ipv6.address.x[4]), - ntohs(subnet->net.ipv6.address.x[5]), - ntohs(subnet->net.ipv6.address.x[6]), - ntohs(subnet->net.ipv6.address.x[7]), - subnet->net.ipv6.prefixlength, - subnet->weight); - break; - - default: - logger(LOG_ERR, - "net2str() was called with unknown subnet type %d, exiting!", - subnet->type); - exit(0); + if((r = hash_search(mac_t, &mac_cache, address))) { + return r; } - return true; -} + // Search all subnets for a matching one -/* Subnet lookup routines */ + for splay_each(subnet_t, p, owner ? &owner->subnet_tree : &subnet_tree) { + if(!p || p->type != SUBNET_MAC) { + continue; + } -subnet_t *lookup_subnet(const node_t *owner, const subnet_t *subnet) { - return splay_search(owner->subnet_tree, subnet); -} + if(!memcmp(address, &p->net.mac.address, sizeof(*address))) { + r = p; -subnet_t *lookup_subnet_mac(const mac_t *address) { - subnet_t *p, subnet = {0}; + if(!p->owner || p->owner->status.reachable) { + break; + } + } + } - subnet.type = SUBNET_MAC; - subnet.net.mac.address = *address; - subnet.owner = NULL; + // Cache the result - p = splay_search(subnet_tree, &subnet); + if(r) { + hash_insert(mac_t, &mac_cache, address, r); + } - return p; + return r; } subnet_t *lookup_subnet_ipv4(const ipv4_t *address) { - subnet_t *p, *r = NULL, subnet = {0}; - splay_node_t *n; - int i; + subnet_t *r = NULL; // Check if this address is cached - for(i = 0; i < 2; i++) { - if(!cache_ipv4_valid[i]) - continue; - if(!memcmp(address, &cache_ipv4_address[i], sizeof *address)) - return cache_ipv4_subnet[i]; + if((r = hash_search(ipv4_t, &ipv4_cache, address))) { + return r; } // Search all subnets for a matching one - subnet.type = SUBNET_IPV4; - subnet.net.ipv4.address = *address; - subnet.net.ipv4.prefixlength = 32; - subnet.owner = NULL; - - for(n = subnet_tree->head; n; n = n->next) { - p = n->data; - - if(!p || p->type != subnet.type) + for splay_each(subnet_t, p, &subnet_tree) { + if(!p || p->type != SUBNET_IPV4) { continue; + } if(!maskcmp(address, &p->net.ipv4.address, p->net.ipv4.prefixlength)) { r = p; - if(p->owner->status.reachable) + + if(!p->owner || p->owner->status.reachable) { break; + } } } // Cache the result - cache_ipv4_slot = !cache_ipv4_slot; - memcpy(&cache_ipv4_address[cache_ipv4_slot], address, sizeof *address); - cache_ipv4_subnet[cache_ipv4_slot] = r; - cache_ipv4_valid[cache_ipv4_slot] = true; + if(r) { + hash_insert(ipv4_t, &ipv4_cache, address, r); + } return r; } subnet_t *lookup_subnet_ipv6(const ipv6_t *address) { - subnet_t *p, *r = NULL, subnet = {0}; - splay_node_t *n; - int i; + subnet_t *r = NULL; // Check if this address is cached - for(i = 0; i < 2; i++) { - if(!cache_ipv6_valid[i]) - continue; - if(!memcmp(address, &cache_ipv6_address[i], sizeof *address)) - return cache_ipv6_subnet[i]; + if((r = hash_search(ipv6_t, &ipv6_cache, address))) { + return r; } // Search all subnets for a matching one - subnet.type = SUBNET_IPV6; - subnet.net.ipv6.address = *address; - subnet.net.ipv6.prefixlength = 128; - subnet.owner = NULL; - - for(n = subnet_tree->head; n; n = n->next) { - p = n->data; - - if(!p || p->type != subnet.type) + for splay_each(subnet_t, p, &subnet_tree) { + if(!p || p->type != SUBNET_IPV6) { continue; + } if(!maskcmp(address, &p->net.ipv6.address, p->net.ipv6.prefixlength)) { r = p; - if(p->owner->status.reachable) + + if(!p->owner || p->owner->status.reachable) { break; + } } } // Cache the result - cache_ipv6_slot = !cache_ipv6_slot; - memcpy(&cache_ipv6_address[cache_ipv6_slot], address, sizeof *address); - cache_ipv6_subnet[cache_ipv6_slot] = r; - cache_ipv6_valid[cache_ipv6_slot] = true; + if(r) { + hash_insert(ipv6_t, &ipv6_cache, address, r); + } return r; } void subnet_update(node_t *owner, subnet_t *subnet, bool up) { - splay_node_t *node; - int i; - char *envp[9] = {0}; + if(!sandbox_can(START_PROCESSES, RIGHT_NOW)) { + return; + } + char netstr[MAXNETSTR]; - char *name, *address, *port; + char *address, *port; char empty[] = ""; // Prepare environment variables to be passed to the script - xasprintf(&envp[0], "NETNAME=%s", netname ? : ""); - xasprintf(&envp[1], "DEVICE=%s", device ? : ""); - xasprintf(&envp[2], "INTERFACE=%s", iface ? : ""); - xasprintf(&envp[3], "NODE=%s", owner->name); + environment_t env; + environment_init(&env); + environment_add(&env, "NODE=%s", owner->name); if(owner != myself) { sockaddr2str(&owner->address, &address, &port); - // 4 and 5 are reserved for SUBNET and WEIGHT - xasprintf(&envp[6], "REMOTEADDRESS=%s", address); - xasprintf(&envp[7], "REMOTEPORT=%s", port); + environment_add(&env, "REMOTEADDRESS=%s", address); + environment_add(&env, "REMOTEPORT=%s", port); + free(port); + free(address); } - name = up ? "subnet-up" : "subnet-down"; + int env_subnet = environment_add(&env, NULL); + int env_weight = environment_add(&env, NULL); + + const char *name = up ? "subnet-up" : "subnet-down"; if(!subnet) { - for(node = owner->subnet_tree->head; node; node = node->next) { - subnet = node->data; - if(!net2str(netstr, sizeof netstr, subnet)) + for splay_each(subnet_t, subnet, &owner->subnet_tree) { + if(!net2str(netstr, sizeof(netstr), subnet)) { continue; + } + // Strip the weight from the subnet, and put it in its own environment variable - char *weight = strchr(netstr + 7, '#'); - if(weight) + char *weight = strchr(netstr, '#'); + + if(weight) { *weight++ = 0; - else + } else { weight = empty; + } // Prepare the SUBNET and WEIGHT variables - if(envp[4]) - free(envp[4]); - if(envp[5]) - free(envp[5]); - xasprintf(&envp[4], "SUBNET=%s", netstr); - xasprintf(&envp[5], "WEIGHT=%s", weight); - - execute_script(name, envp); + environment_update(&env, env_subnet, "SUBNET=%s", netstr); + environment_update(&env, env_weight, "WEIGHT=%s", weight); + + execute_script(name, &env); } } else { - if(net2str(netstr + 7, sizeof netstr - 7, subnet)) { + if(net2str(netstr, sizeof(netstr), subnet)) { // Strip the weight from the subnet, and put it in its own environment variable - char *weight = strchr(netstr + 7, '#'); - if(weight) + char *weight = strchr(netstr, '#'); + + if(weight) { *weight++ = 0; - else + } else { weight = empty; + } // Prepare the SUBNET and WEIGHT variables - xasprintf(&envp[4], "SUBNET=%s", netstr); - xasprintf(&envp[5], "WEIGHT=%s", weight); + environment_update(&env, env_subnet, "SUBNET=%s", netstr); + environment_update(&env, env_weight, "WEIGHT=%s", weight); - execute_script(name, envp); + execute_script(name, &env); } } - for(i = 0; envp[i] && i < 9; i++) - free(envp[i]); + environment_exit(&env); } -int dump_subnets(struct evbuffer *out) { - char netstr[MAXNETSTR]; - subnet_t *subnet; - splay_node_t *node; +bool dump_subnets(connection_t *c) { + for splay_each(subnet_t, subnet, &subnet_tree) { + char netstr[MAXNETSTR]; - for(node = subnet_tree->head; node; node = node->next) { - subnet = node->data; - if(!net2str(netstr, sizeof netstr, subnet)) + if(!net2str(netstr, sizeof(netstr), subnet)) { continue; - if(evbuffer_add_printf(out, " %s owner %s\n", - netstr, subnet->owner->name) == -1) - return errno; + } + + send_request(c, "%d %d %s %s", + CONTROL, REQ_DUMP_SUBNETS, + netstr, subnet->owner ? subnet->owner->name : "(broadcast)"); } - return 0; + return send_request(c, "%d %d", CONTROL, REQ_DUMP_SUBNETS); }