X-Git-Url: https://tinc-vpn.org/git/browse?a=blobdiff_plain;f=src%2Fsubnet.c;h=4fefda6ff8f47996c380eabf2165da7d72b1aa9f;hb=refs%2Fheads%2F1.1;hp=59e4e8245d42efacad377cf28c52f580194c29e6;hpb=d6388d782ede1bbe49a5c2643362e2e0f383fa89;p=tinc diff --git a/src/subnet.c b/src/subnet.c index 59e4e824..94000cc0 100644 --- a/src/subnet.c +++ b/src/subnet.c @@ -1,6 +1,6 @@ /* subnet.c -- handle subnet lookups and lists - Copyright (C) 2000-2012 Guus Sliepen , + Copyright (C) 2000-2022 Guus Sliepen , 2000-2005 Ivo Timmermans This program is free software; you can redistribute it and/or modify @@ -22,270 +22,387 @@ #include "splay_tree.h" #include "control_common.h" -#include "device.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 */ -hash_t *ipv4_cache; -hash_t *ipv6_cache; -hash_t *mac_cache; +static uint32_t wrapping_add32(uint32_t a, uint32_t b) { + return (uint32_t)((uint64_t)a + b); +} -void subnet_cache_flush(void) { - hash_clear(ipv4_cache); - hash_clear(ipv6_cache); - hash_clear(mac_cache); +static uint32_t wrapping_mul32(uint32_t a, uint32_t b) { + return (uint32_t)((uint64_t)a * b); } -/* Initialising trees */ +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 +} -void init_subnets(void) { - subnet_tree = splay_alloc_tree((splay_compare_t) subnet_compare, (splay_action_t) free_subnet); - ipv4_cache = hash_alloc(0x100, sizeof(ipv4_t)); - ipv6_cache = hash_alloc(0x100, sizeof(ipv6_t)); - mac_cache = hash_alloc(0x100, sizeof(mac_t)); +static uint32_t hash_function_ipv6_t(const ipv6_t *p) { + uint32_t *fullwidth = (uint32_t *)p; + uint32_t hash = hash_seed; + + for(int i = 0; i < 4; i++) { + hash = wrapping_add32(hash, fullwidth[i]); + hash = wrapping_mul32(hash, 0x9e370001U); + } + + return hash; } -void exit_subnets(void) { - splay_delete_tree(subnet_tree); +static uint32_t hash_function_mac_t(const mac_t *p) { + uint16_t *halfwidth = (uint16_t *)p; + uint32_t hash = hash_seed; - hash_free(ipv4_cache); - hash_free(ipv6_cache); - hash_free(mac_cache); + for(int i = 0; i < 3; i++) { + hash = wrapping_add32(hash, halfwidth[i]); + hash = wrapping_mul32(hash, 0x9e370001U); + } + + return hash; } -splay_tree_t *new_subnet_tree(void) { - return splay_alloc_tree((splay_compare_t) subnet_compare, NULL); +hash_define(ipv4_t, SUBNET_HASH_SIZE) +hash_define(ipv6_t, SUBNET_HASH_SIZE) +hash_define(mac_t, SUBNET_HASH_SIZE) + +hash_new(ipv4_t, ipv4_cache); +hash_new(ipv6_t, ipv6_cache); +hash_new(mac_t, mac_cache); + + +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(stype != SUBNET_IPV6) { // ipv4 + hash_clear(ipv4_t, &ipv4_cache); + } + + if(stype != SUBNET_IPV4) { // ipv6 + hash_clear(ipv6_t, &ipv6_cache); + } + + hash_clear(mac_t, &mac_cache); +} + +/* Initialising trees */ + +void init_subnets(void) { + hash_seed = prng(UINT32_MAX); + + // tables need to be cleared on startup + subnet_cache_flush_tables(); } -void free_subnet_tree(splay_tree_t *subnet_tree) { - splay_delete_tree(subnet_tree); +void exit_subnets(void) { + splay_empty_tree(&subnet_tree); + subnet_cache_flush_tables(); +} + +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); } +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); +} + +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; + } + + break; + + case SUBNET_IPV6: + if(subnet->net.ipv4.prefixlength == 128) { + hash_delete(ipv6_t, &ipv6_cache, &subnet->net.ipv6.address); + return; + } + + break; + + case SUBNET_MAC: + hash_delete(mac_t, &mac_cache, &subnet->net.mac.address); + return; + } + + subnet_cache_flush_table(subnet->type); +} + /* 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); + splay_insert(&subnet_tree, subnet); + + if(n) { + splay_insert(&n->subnet_tree, subnet); + } - subnet_cache_flush(); + subnet_cache_flush(subnet); } void subnet_del(node_t *n, subnet_t *subnet) { - splay_delete(n->subnet_tree, subnet); - splay_delete(subnet_tree, subnet); + if(n) { + splay_delete(&n->subnet_tree, subnet); + } + + splay_delete(&subnet_tree, subnet); - subnet_cache_flush(); + subnet_cache_flush(subnet); } /* Subnet lookup routines */ -subnet_t *lookup_subnet(const node_t *owner, const subnet_t *subnet) { - return splay_search(owner->subnet_tree, subnet); +subnet_t *lookup_subnet(node_t *owner, const subnet_t *subnet) { + return splay_search(&owner->subnet_tree, subnet); } subnet_t *lookup_subnet_mac(const node_t *owner, const mac_t *address) { - subnet_t *p, *r = NULL; - splay_node_t *n; + subnet_t *r = NULL; // Check if this address is cached - if((r = hash_search(mac_cache, address))) + if((r = hash_search(mac_t, &mac_cache, address))) { return r; + } // Search all subnets for a matching one - for(n = owner ? owner->subnet_tree->head : subnet_tree->head; n; n = n->next) { - p = n->data; - - if(!p || p->type != SUBNET_MAC) + for splay_each(subnet_t, p, owner ? &owner->subnet_tree : &subnet_tree) { + if(!p || p->type != SUBNET_MAC) { continue; + } - if(!memcmp(address, &p->net.mac.address, sizeof *address)) { + if(!memcmp(address, &p->net.mac.address, sizeof(*address))) { r = p; - if(p->owner->status.reachable) + + if(!p->owner || p->owner->status.reachable) { break; + } } } // Cache the result - if(r) - hash_insert(mac_cache, address, r); + if(r) { + hash_insert(mac_t, &mac_cache, address, r); + } return r; } subnet_t *lookup_subnet_ipv4(const ipv4_t *address) { - subnet_t *p, *r = NULL; - splay_node_t *n; + subnet_t *r = NULL; // Check if this address is cached - if((r = hash_search(ipv4_cache, address))) + if((r = hash_search(ipv4_t, &ipv4_cache, address))) { return r; + } // Search all subnets for a matching one - for(n = subnet_tree->head; n; n = n->next) { - p = n->data; - - if(!p || p->type != SUBNET_IPV4) + 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 - if(r) - hash_insert(ipv4_cache, address, r); + 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; - splay_node_t *n; + subnet_t *r = NULL; // Check if this address is cached - if((r = hash_search(ipv6_cache, address))) + if((r = hash_search(ipv6_t, &ipv6_cache, address))) { return r; + } // Search all subnets for a matching one - for(n = subnet_tree->head; n; n = n->next) { - p = n->data; - - if(!p || p->type != SUBNET_IPV6) + 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 - if(r) - hash_insert(ipv6_cache, address, r); + 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] = {NULL}; + 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, '#'); - if(weight) + + 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, sizeof netstr, 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, '#'); - if(weight) + + 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 < 8; i++) - free(envp[i]); + environment_exit(&env); } bool dump_subnets(connection_t *c) { - char netstr[MAXNETSTR]; - subnet_t *subnet; - splay_node_t *node; + 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; + } + send_request(c, "%d %d %s %s", - CONTROL, REQ_DUMP_SUBNETS, - netstr, subnet->owner->name); + CONTROL, REQ_DUMP_SUBNETS, + netstr, subnet->owner ? subnet->owner->name : "(broadcast)"); } return send_request(c, "%d %d", CONTROL, REQ_DUMP_SUBNETS);