/*
subnet.c -- handle subnet lookups and lists
- Copyright (C) 2000 Guus Sliepen <guus@sliepen.warande.net>,
- 2000 Ivo Timmermans <itimmermans@bigfoot.com>
+ Copyright (C) 2000-2022 Guus Sliepen <guus@tinc-vpn.org>,
+ 2000-2005 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
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: subnet.c,v 1.1.2.5 2000/10/24 15:46:18 guus 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.
*/
-#include "config.h"
-#include <utils.h>
+#include "system.h"
-#include <xalloc.h>
-#include "subnet.h"
+#include "splay_tree.h"
+#include "control_common.h"
+#include "crypto.h"
+#include "hash.h"
+#include "logger.h"
#include "net.h"
+#include "netutl.h"
+#include "node.h"
+#include "script.h"
+#include "subnet.h"
+#include "xalloc.h"
+
+/* lists type of subnet */
+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 uint32_t wrapping_add32(uint32_t a, uint32_t b) {
+ return (uint32_t)((uint64_t)a + b);
+}
+
+static uint32_t wrapping_mul32(uint32_t a, uint32_t b) {
+ return (uint32_t)((uint64_t)a * b);
+}
+
+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
+}
+
+
+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;
+}
+
+static uint32_t hash_function_mac_t(const mac_t *p) {
+ uint16_t *halfwidth = (uint16_t *)p;
+ uint32_t hash = hash_seed;
+
+ for(int i = 0; i < 3; i++) {
+ hash = wrapping_add32(hash, halfwidth[i]);
+ hash = wrapping_mul32(hash, 0x9e370001U);
+ }
+
+ return hash;
+}
+
+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 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)
-{
-cp
- return (subnet_t *)xmalloc(sizeof(subnet_t));
+subnet_t *new_subnet(void) {
+ return xzalloc(sizeof(subnet_t));
}
-void free_subnet(subnet_t *subnet)
-{
-cp
- free(subnet);
+void free_subnet(subnet_t *subnet) {
+ free(subnet);
}
-/* Linked list management */
-
-void subnet_add(conn_list_t *cl, subnet_t *subnet)
-{
- subnet_t *p = NULL;
- subnet_t *q = NULL;
-cp
- subnet->owner = cl;
-
- /* Sort on size of subnet mask (IPv4 only at the moment!)
-
- Three cases: cl->subnets = NULL -> just add this subnet
- insert before first -> add it in front of list
- rest: insert after another subnet
- */
-
- if(cl->subnets)
- {
- p = q = cl->subnets;
-
- for(; p; p = p->next)
- {
- if(subnet->net.ipv4.mask >= p->net.ipv4.mask)
- break;
-
- q = p;
- }
- }
-
- if(!cl->subnets || p == cl->subnets) /* First two cases */
- {
- /* Insert in front */
- subnet->next = cl->subnets;
- subnet->prev = NULL;
- cl->subnets = subnet;
- }
- else /* Third case */
- {
- /* Insert after q */
- subnet->next = q->next;
- subnet->prev = q;
- q->next = subnet;
- }
-
- if(subnet->next)
- subnet->next->prev = subnet;
-cp
+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(subnet_t *subnet)
-{
-cp
- if(subnet->prev)
- subnet->prev->next = subnet->next;
- else
- subnet->owner->subnets = subnet->next;
+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;
- if(subnet->next)
- subnet->next->prev = subnet->prev;
+ case SUBNET_IPV6:
+ if(subnet->net.ipv4.prefixlength == 128) {
+ hash_delete(ipv6_t, &ipv6_cache, &subnet->net.ipv6.address);
+ return;
+ }
- free_subnet(subnet);
-cp
+ break;
+
+ case SUBNET_MAC:
+ hash_delete(mac_t, &mac_cache, &subnet->net.mac.address);
+ return;
+ }
+
+ subnet_cache_flush_table(subnet->type);
}
-/* Ascii representation of subnets */
-
-subnet_t *str2net(char *subnetstr)
-{
- int type;
- subnet_t *subnet;
-cp
- if(sscanf(subnetstr, "%d,", &type) != 1)
- return NULL;
-
- subnet = new_subnet();
-
- switch(type)
- {
- case SUBNET_MAC:
- if(sscanf(subnetstr, "%d,%hhx:%hhx:%hhx:%hhx:%hhx:%hhx", &subnet->type,
- &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]) != 7)
- {
- free_subnet(subnet);
- return NULL;
- }
- break;
- case SUBNET_IPV4:
- if(sscanf(subnetstr, "%d,%lx/%lx", &subnet->type, &subnet->net.ipv4.address, &subnet->net.ipv4.mask) != 3)
- {
- free_subnet(subnet);
- return NULL;
- }
- break;
- case SUBNET_IPV6:
- if(sscanf(subnetstr, "%d,%hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx/%hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx", &subnet->type,
- &subnet->net.ipv6.address.x[0],
- &subnet->net.ipv6.address.x[1],
- &subnet->net.ipv6.address.x[2],
- &subnet->net.ipv6.address.x[3],
- &subnet->net.ipv6.address.x[4],
- &subnet->net.ipv6.address.x[5],
- &subnet->net.ipv6.address.x[6],
- &subnet->net.ipv6.address.x[7],
- &subnet->net.ipv6.mask.x[0],
- &subnet->net.ipv6.mask.x[1],
- &subnet->net.ipv6.mask.x[2],
- &subnet->net.ipv6.mask.x[3],
- &subnet->net.ipv6.mask.x[4],
- &subnet->net.ipv6.mask.x[5],
- &subnet->net.ipv6.mask.x[6],
- &subnet->net.ipv6.mask.x[7]) != 17)
- {
- free_subnet(subnet);
- return NULL;
- }
- break;
- break;
- default:
- free_subnet(subnet);
- return NULL;
- }
-cp
- return subnet;
+/* Adding and removing subnets */
+
+void subnet_add(node_t *n, subnet_t *subnet) {
+ subnet->owner = n;
+
+ splay_insert(&subnet_tree, subnet);
+
+ if(n) {
+ splay_insert(&n->subnet_tree, subnet);
+ }
+
+ subnet_cache_flush(subnet);
}
-char *net2str(subnet_t *subnet)
-{
- char *netstr;
-cp
- switch(subnet->type)
- {
- case SUBNET_MAC:
- asprintf(&netstr, "%d,%hhx:%hhx:%hhx:%hhx:%hhx:%hhx", subnet->type,
- 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]);
- break;
- case SUBNET_IPV4:
- asprintf(&netstr, "%d,%lx/%lx", subnet->type, subnet->net.ipv4.address, subnet->net.ipv4.mask);
- break;
- case SUBNET_IPV6:
- asprintf(&netstr, "%d,%hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx/%hx:%hx:%hx:%hx:%hx:%hx:%hx:%hx",
- subnet->net.ipv6.address.x[0],
- subnet->net.ipv6.address.x[1],
- subnet->net.ipv6.address.x[2],
- subnet->net.ipv6.address.x[3],
- subnet->net.ipv6.address.x[4],
- subnet->net.ipv6.address.x[5],
- subnet->net.ipv6.address.x[6],
- subnet->net.ipv6.address.x[7],
- subnet->net.ipv6.mask.x[0],
- subnet->net.ipv6.mask.x[1],
- subnet->net.ipv6.mask.x[2],
- subnet->net.ipv6.mask.x[3],
- subnet->net.ipv6.mask.x[4],
- subnet->net.ipv6.mask.x[5],
- subnet->net.ipv6.mask.x[6],
- subnet->net.ipv6.mask.x[7]);
- break;
- default:
- netstr = NULL;
- }
-cp
- return netstr;
+void subnet_del(node_t *n, subnet_t *subnet) {
+ if(n) {
+ splay_delete(&n->subnet_tree, subnet);
+ }
+
+ splay_delete(&subnet_tree, subnet);
+
+ subnet_cache_flush(subnet);
}
/* Subnet lookup routines */
-subnet_t *lookup_subnet_mac(subnet_t *subnets, mac_t address)
-{
- subnet_t *subnet;
-cp
- for(subnet = subnets; subnet != NULL; subnet = subnet->next)
- {
- if(subnet->type == SUBNET_MAC)
- if(memcmp(&address, &subnet->net.mac.address, sizeof(address)) == 0)
- break;
- }
-cp
- return 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 *r = NULL;
+
+ // Check if this address is cached
+
+ if((r = hash_search(mac_t, &mac_cache, address))) {
+ return r;
+ }
+
+ // Search all subnets for a matching one
+
+ 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))) {
+ r = p;
+
+ if(!p->owner || p->owner->status.reachable) {
+ break;
+ }
+ }
+ }
+
+ // Cache the result
+
+ if(r) {
+ hash_insert(mac_t, &mac_cache, address, r);
+ }
+
+ return r;
}
-subnet_t *lookup_subnet_ipv4(subnet_t *subnets, ipv4_t address)
-{
- subnet_t *subnet;
-cp
- for(subnet = subnets; subnet != NULL; subnet = subnet->next)
- {
- if(subnet->type == SUBNET_IPV4)
- if((address & subnet->net.ipv4.mask) == subnet->net.ipv4.address)
- break;
- }
-cp
- return subnet;
+subnet_t *lookup_subnet_ipv4(const ipv4_t *address) {
+ subnet_t *r = NULL;
+
+ // Check if this address is cached
+
+ if((r = hash_search(ipv4_t, &ipv4_cache, address))) {
+ return r;
+ }
+
+ // Search all subnets for a matching one
+
+ 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 || p->owner->status.reachable) {
+ break;
+ }
+ }
+ }
+
+ // Cache the result
+
+ if(r) {
+ hash_insert(ipv4_t, &ipv4_cache, address, r);
+ }
+
+ return r;
}
-subnet_t *lookup_subnet_ipv6(subnet_t *subnets, ipv6_t address)
-{
- subnet_t *subnet;
- int i;
-cp
- for(subnet = subnets; subnet != NULL; subnet = subnet->next)
- {
- if(subnet->type == SUBNET_IPV6)
- {
- for(i=0; i<8; i++)
- if((address.x[i] & subnet->net.ipv6.mask.x[i]) != subnet->net.ipv6.address.x[i])
- break;
- if(i=8)
- break;
- }
- }
-cp
- return subnet;
+subnet_t *lookup_subnet_ipv6(const ipv6_t *address) {
+ subnet_t *r = NULL;
+
+ // Check if this address is cached
+
+ if((r = hash_search(ipv6_t, &ipv6_cache, address))) {
+ return r;
+ }
+
+ // Search all subnets for a matching one
+
+ 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 || p->owner->status.reachable) {
+ break;
+ }
+ }
+ }
+
+ // Cache the result
+
+ if(r) {
+ hash_insert(ipv6_t, &ipv6_cache, address, r);
+ }
+
+ return r;
+}
+
+void subnet_update(node_t *owner, subnet_t *subnet, bool up) {
+ char netstr[MAXNETSTR];
+ char *address, *port;
+ char empty[] = "";
+
+ // Prepare environment variables to be passed to the script
+
+ environment_t env;
+ environment_init(&env);
+ environment_add(&env, "NODE=%s", owner->name);
+
+ if(owner != myself) {
+ sockaddr2str(&owner->address, &address, &port);
+ environment_add(&env, "REMOTEADDRESS=%s", address);
+ environment_add(&env, "REMOTEPORT=%s", port);
+ free(port);
+ free(address);
+ }
+
+ 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 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) {
+ *weight++ = 0;
+ } else {
+ weight = empty;
+ }
+
+ // Prepare the SUBNET and WEIGHT variables
+ 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)) {
+ // Strip the weight from the subnet, and put it in its own environment variable
+ char *weight = strchr(netstr, '#');
+
+ if(weight) {
+ *weight++ = 0;
+ } else {
+ weight = empty;
+ }
+
+ // Prepare the SUBNET and WEIGHT variables
+ environment_update(&env, env_subnet, "SUBNET=%s", netstr);
+ environment_update(&env, env_weight, "WEIGHT=%s", weight);
+
+ execute_script(name, &env);
+ }
+ }
+
+ environment_exit(&env);
+}
+
+bool dump_subnets(connection_t *c) {
+ for splay_each(subnet_t, subnet, &subnet_tree) {
+ char netstr[MAXNETSTR];
+
+ if(!net2str(netstr, sizeof(netstr), subnet)) {
+ continue;
+ }
+
+ send_request(c, "%d %d %s %s",
+ CONTROL, REQ_DUMP_SUBNETS,
+ netstr, subnet->owner ? subnet->owner->name : "(broadcast)");
+ }
+
+ return send_request(c, "%d %d", CONTROL, REQ_DUMP_SUBNETS);
}