/* * * Connection Manager * * Copyright (C) 2007-2013 Intel Corporation. All rights reserved. * Copyright (C) 2012-2014 BMW Car IT GmbH. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * 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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA * */ #ifdef HAVE_CONFIG_H #include #endif #include #include #include #include #include #include #include "connman.h" struct address_info { int index; uint32_t start; uint32_t end; unsigned int use_count; struct connman_ippool *pool; }; struct connman_ippool { unsigned int refcount; struct address_info *info; char *gateway; char *broadcast; char *start_ip; char *end_ip; char *subnet_mask; ippool_collision_cb_t collision_cb; void *user_data; }; GSList *allocated_blocks; GHashTable *pool_hash; static uint32_t last_block; static uint32_t block_16_bits; static uint32_t block_20_bits; static uint32_t block_24_bits; static uint32_t subnet_mask_24; struct connman_ippool * __connman_ippool_ref_debug(struct connman_ippool *pool, const char *file, int line, const char *caller) { DBG("%p ref %d by %s:%d:%s()", pool, pool->refcount + 1, file, line, caller); __sync_fetch_and_add(&pool->refcount, 1); return pool; } void __connman_ippool_unref_debug(struct connman_ippool *pool, const char *file, int line, const char *caller) { if (!pool) return; DBG("%p ref %d by %s:%d:%s()", pool, pool->refcount - 1, file, line, caller); if (__sync_fetch_and_sub(&pool->refcount, 1) != 1) return; g_hash_table_remove(pool_hash, pool); } static char *get_ip(uint32_t ip) { struct in_addr addr; addr.s_addr = htonl(ip); return g_strdup(inet_ntoa(addr)); } static uint32_t next_block(uint32_t block) { uint32_t next; /* * Return the next IP block within the private IP range * * 16-bit block 192.168.0.0 – 192.168.255.255 * 20-bit block 172.16.0.0 – 172.31.255.255 * 24-bit block 10.0.0.0 – 10.255.255.255 */ next = (block & 0x0000ff00) >> 8; next += 1; if (next == 255) { if ((block & 0xffff0000) == block_16_bits) { /* * Reached the end of the 16 bit block, switch * to the 20-bit block. */ return block_20_bits; } if ((block & 0xffff0000) >= block_20_bits) { next = (block & 0x00ff0000) >> 16; if (next >= 16 && next < 32) next += 1; if (next == 32) { /* * Reached the end of the 20 bit * block, switch to the 24-bit block. */ return block_24_bits; } return (block & 0xff000000) | ((next << 16) & 0x00ff0000); } if ((block & 0xff000000) == block_24_bits) { next = (block & 0x00ff0000) >> 16; if (next < 255) next += 1; if (next == 255) { /* * Reached the end of the 24 bit * block, switch to the 16-bit block. */ return block_16_bits; } return (block & 0xff000000) | ((next << 16) & 0x00ff0000); } } return (block & 0xffff0000) | ((next << 8) & 0x0000ff00); } static uint32_t get_free_block(unsigned int size) { struct address_info *info; uint32_t block; GSList *list; bool collision; /* * Instead starting always from the 16 bit block, we start * from the last assigned block. This is a simple optimimazion * for the case where a lot of blocks have been assigned, e.g. * the first half of the private IP pool is in use and a new * we need to find a new block. * * To only thing we have to make sure is that we terminated if * there is no block left. */ if (last_block == 0) block = block_16_bits; else block = next_block(last_block); do { collision = false; for (list = allocated_blocks; list; list = list->next) { info = list->data; if (info->start <= block && block <= info->end) { collision = true; break; } } if (!collision) return block; block = next_block(block); } while (block != last_block); return 0; } static struct address_info *lookup_info(int index, uint32_t start) { GSList *list; for (list = allocated_blocks; list; list = list->next) { struct address_info *info = list->data; if (info->index == index && info->start == start) return info; } return NULL; } static bool is_private_address(uint32_t address) { unsigned int a, b; a = (address & 0xff000000) >> 24; b = (address & 0x00ff0000) >> 16; if (a == 10 || (a == 192 && b == 168) || (a == 172 && (b >= 16 && b <= 31))) return true; return false; } void __connman_ippool_newaddr(int index, const char *address, unsigned char prefixlen) { struct address_info *info, *it; struct in_addr inp; uint32_t start, end, mask; GSList *list; if (inet_aton(address, &inp) == 0) return; start = ntohl(inp.s_addr); if (!is_private_address(start)) return; if (prefixlen >= 32) mask = 0xffffffff; else mask = ~(0xffffffff >> prefixlen); start = start & mask; end = start | ~mask; info = lookup_info(index, start); if (info) goto update; info = g_try_new0(struct address_info, 1); if (!info) return; info->index = index; info->start = start; info->end = end; allocated_blocks = g_slist_prepend(allocated_blocks, info); update: info->use_count = info->use_count + 1; if (info->use_count > 1 || info->pool) { /* * We need only to check for the first IP in a block for * collisions. */ return; } for (list = allocated_blocks; list; list = list->next) { it = list->data; if (it == info) continue; if (!(info->start >= it->start && info->start <= it->end)) continue; if (it->pool && it->pool->collision_cb) it->pool->collision_cb(it->pool, it->pool->user_data); return; } } void __connman_ippool_deladdr(int index, const char *address, unsigned char prefixlen) { struct address_info *info; struct in_addr inp; uint32_t start, mask; if (inet_aton(address, &inp) == 0) return; start = ntohl(inp.s_addr); if (!is_private_address(start)) return; mask = ~(0xffffffff >> prefixlen); start = start & mask; info = lookup_info(index, start); if (!info) { /* In theory this should never happen */ connman_error("Inconsistent IP pool management (start not found)"); return; } info->use_count = info->use_count - 1; if (info->pool) return; if (info->use_count > 0) return; allocated_blocks = g_slist_remove(allocated_blocks, info); g_free(info); } struct connman_ippool *__connman_ippool_create(int index, unsigned int start, unsigned int range, ippool_collision_cb_t collision_cb, void *user_data) { struct connman_ippool *pool; struct address_info *info; uint32_t block; DBG(""); /* * The range is at max 255 and we don't support overlapping * blocks. */ if (start + range > 254) { connman_error("IP pool does not support pool size larger than 254"); return NULL; } block = get_free_block(start + range); if (block == 0) { connman_warn("Could not find a free IP block"); return NULL; } pool = g_try_new0(struct connman_ippool, 1); if (!pool) return NULL; info = g_try_new0(struct address_info, 1); if (!info) { g_free(pool); return NULL; } last_block = block; info->index = index; info->start = block; info->end = block + range; pool->refcount = 1; pool->info = info; pool->collision_cb = collision_cb; pool->user_data = user_data; info->pool = pool; if (range == 0) range = 1; pool->gateway = get_ip(info->start + 1); pool->broadcast = get_ip(info->start + 255); pool->subnet_mask = get_ip(subnet_mask_24); pool->start_ip = get_ip(block + start); pool->end_ip = get_ip(block + start + range); allocated_blocks = g_slist_prepend(allocated_blocks, info); g_hash_table_insert(pool_hash, pool, pool); return pool; } const char *__connman_ippool_get_gateway(struct connman_ippool *pool) { return pool->gateway; } const char *__connman_ippool_get_broadcast(struct connman_ippool *pool) { return pool->broadcast; } const char *__connman_ippool_get_start_ip(struct connman_ippool *pool) { return pool->start_ip; } const char *__connman_ippool_get_end_ip(struct connman_ippool *pool) { return pool->end_ip; } const char *__connman_ippool_get_subnet_mask(struct connman_ippool *pool) { return pool->subnet_mask; } static void pool_free(gpointer data) { struct connman_ippool *pool = data; if (pool->info) { allocated_blocks = g_slist_remove(allocated_blocks, pool->info); g_free(pool->info); } g_free(pool->gateway); g_free(pool->broadcast); g_free(pool->start_ip); g_free(pool->end_ip); g_free(pool->subnet_mask); g_free(pool); } int __connman_ippool_init(void) { DBG(""); block_16_bits = ntohl(inet_addr("192.168.0.0")); block_20_bits = ntohl(inet_addr("172.16.0.0")); block_24_bits = ntohl(inet_addr("10.0.0.0")); subnet_mask_24 = ntohl(inet_addr("255.255.255.0")); pool_hash = g_hash_table_new_full(g_direct_hash, g_direct_equal, NULL, pool_free); return 0; } void __connman_ippool_cleanup(void) { DBG(""); g_hash_table_destroy(pool_hash); pool_hash = NULL; g_slist_free_full(allocated_blocks, g_free); last_block = 0; allocated_blocks = NULL; }