From 68ce6b3f0f39867d2fca4c3f051447634fd03fd9 Mon Sep 17 00:00:00 2001 From: Nick Peng Date: Mon, 16 May 2022 22:52:22 +0800 Subject: [PATCH] dns_server: fix ipv6 multi ipaddress issue --- src/dns_server.c | 86 ++++++++++++++++++++++++++++++++---------------- 1 file changed, 57 insertions(+), 29 deletions(-) diff --git a/src/dns_server.c b/src/dns_server.c index 019ac52..25448d7 100644 --- a/src/dns_server.c +++ b/src/dns_server.c @@ -138,6 +138,7 @@ struct dns_ip_address { unsigned long recv_tick; int ping_ttl; dns_type_t addr_type; + char cname[DNS_MAX_CNAME_LEN]; union { unsigned char ipv4_addr[DNS_RR_A_LEN]; unsigned char ipv6_addr[DNS_RR_AAAA_LEN]; @@ -677,9 +678,9 @@ static int _dns_add_rrs(struct dns_server_post_context *context) ret |= dns_add_AAAA(context->packet, DNS_RRS_AN, domain, request->ttl_v6, request->ipv6_addr); context->ip_num++; tlog(TLOG_INFO, - "result: %s, rcode: %d, index: %d, " + "result: %s, rcode: %d, index: %d, rtt: %d, " "%.2x%.2x:%.2x%.2x:%.2x%.2x:%.2x%.2x:%.2x%.2x:%.2x%.2x:%.2x%.2x:%.2x%.2x", - request->domain, request->rcode, context->ip_num, request->ipv6_addr[0], request->ipv6_addr[1], + request->domain, request->rcode, context->ip_num, request->ping_ttl_v6, request->ipv6_addr[0], request->ipv6_addr[1], request->ipv6_addr[2], request->ipv6_addr[3], request->ipv6_addr[4], request->ipv6_addr[5], request->ipv6_addr[6], request->ipv6_addr[7], request->ipv6_addr[8], request->ipv6_addr[9], request->ipv6_addr[10], request->ipv6_addr[11], request->ipv6_addr[12], request->ipv6_addr[13], @@ -1342,7 +1343,7 @@ out: return _dns_server_reply_all_pending_list(request, &context); } -static int _dns_ip_address_check_add(struct dns_request *request, unsigned char *addr, dns_type_t addr_type) +static int _dns_ip_address_check_add(struct dns_request *request, char *cname, unsigned char *addr, dns_type_t addr_type) { uint32_t key = 0; struct dns_ip_address *addr_map = NULL; @@ -1391,6 +1392,7 @@ static int _dns_ip_address_check_add(struct dns_request *request, unsigned char addr_map->recv_tick = get_tick_count(); addr_map->ping_ttl = -1; memcpy(addr_map->addr, addr, addr_len); + safe_strncpy(addr_map->cname, cname, DNS_MAX_CNAME_LEN); hash_add(request->ip_map, &addr_map->node, key); pthread_mutex_unlock(&request->ip_map_lock); @@ -1697,17 +1699,24 @@ static void _dns_server_ping_result(struct ping_host_struct *ping_host, const ch case AF_INET: { struct sockaddr_in *addr_in; addr_in = (struct sockaddr_in *)addr; + addr_map = _dns_ip_address_get(request, (unsigned char *)&addr_in->sin_addr.s_addr, DNS_T_A); + if (addr_map) { + addr_map->ping_ttl = rtt; + } + if (request->ping_ttl_v4 > rtt || request->ping_ttl_v4 == -1) { memcpy(request->ipv4_addr, &addr_in->sin_addr.s_addr, 4); tlog(TLOG_INFO, "ping result: %s, rcode: %d, %d.%d.%d.%d, ping_ttl: %d, rtt: %d\n", request->domain, request->rcode, request->ipv4_addr[0], request->ipv4_addr[1], request->ipv4_addr[2], request->ipv4_addr[3], request->ping_ttl_v4, rtt); request->ping_ttl_v4 = rtt; - } - - addr_map = _dns_ip_address_get(request, (unsigned char *)&addr_in->sin_addr.s_addr, DNS_T_A); - if (addr_map) { - addr_map->ping_ttl = rtt; + request->has_cname = 0; + if (addr_map && addr_map->cname[0] != 0) { + request->has_cname = 1; + safe_strncpy(request->cname, addr_map->cname, DNS_MAX_CNAME_LEN); + } else { + request->has_cname = 0; + } } if (request->qtype == DNS_T_AAAA && request->dualstack_selection) { @@ -1720,21 +1729,35 @@ static void _dns_server_ping_result(struct ping_host_struct *ping_host, const ch struct sockaddr_in6 *addr_in6; addr_in6 = (struct sockaddr_in6 *)addr; if (IN6_IS_ADDR_V4MAPPED(&addr_in6->sin6_addr)) { + addr_map = _dns_ip_address_get(request, addr_in6->sin6_addr.s6_addr + 12, DNS_T_A); + if (addr_map) { + addr_map->ping_ttl = rtt; + } + if (request->ping_ttl_v4 > rtt || request->ping_ttl_v4 == -1) { request->ping_ttl_v4 = rtt; memcpy(request->ipv4_addr, addr_in6->sin6_addr.s6_addr + 12, 4); - addr_map = _dns_ip_address_get(request, addr_in6->sin6_addr.s6_addr + 12, DNS_T_A); - if (addr_map) { - addr_map->ping_ttl = rtt; + if (addr_map && addr_map->cname[0] != 0) { + request->has_cname = 1; + safe_strncpy(request->cname, addr_map->cname, DNS_MAX_CNAME_LEN); + } else { + request->has_cname = 0; } } } else { + addr_map = _dns_ip_address_get(request, addr_in6->sin6_addr.s6_addr, DNS_T_AAAA); + if (addr_map) { + addr_map->ping_ttl = rtt; + } + if (request->ping_ttl_v6 > rtt || request->ping_ttl_v6 == -1) { request->ping_ttl_v6 = rtt; memcpy(request->ipv6_addr, addr_in6->sin6_addr.s6_addr, 16); - addr_map = _dns_ip_address_get(request, addr_in6->sin6_addr.s6_addr, DNS_T_AAAA); - if (addr_map) { - addr_map->ping_ttl = rtt; + if (addr_map && addr_map->cname[0] != 0) { + request->has_cname = 1; + safe_strncpy(request->cname, addr_map->cname, DNS_MAX_CNAME_LEN); + } else { + request->has_cname = 0; } } } @@ -1886,7 +1909,7 @@ static int _dns_server_is_adblock_ipv6(unsigned char addr[16]) return -1; } -static int _dns_server_process_answer_A(struct dns_rrs *rrs, struct dns_request *request, char *domain, +static int _dns_server_process_answer_A(struct dns_rrs *rrs, struct dns_request *request, char *domain, char *cname, unsigned int result_flag, int ping_timeout) { int ttl; @@ -1920,7 +1943,7 @@ static int _dns_server_process_answer_A(struct dns_rrs *rrs, struct dns_request } /* if domain is not match */ - if (strncmp(name, domain, DNS_MAX_CNAME_LEN) != 0 && strncmp(request->cname, name, DNS_MAX_CNAME_LEN) != 0) { + if (strncmp(name, domain, DNS_MAX_CNAME_LEN) != 0 && strncmp(cname, name, DNS_MAX_CNAME_LEN) != 0) { _dns_server_request_release(request); return -1; } @@ -1929,6 +1952,10 @@ static int _dns_server_process_answer_A(struct dns_rrs *rrs, struct dns_request request->has_ipv4 = 1; memcpy(request->ipv4_addr, addr, DNS_RR_A_LEN); request->ttl_v4 = _dns_server_get_conf_ttl(ttl); + if (cname[0] != 0 && request->has_cname == 0) { + request->has_cname = 1; + safe_strncpy(request->cname, cname, DNS_MAX_CNAME_LEN); + } } else { if (ttl < request->ttl_v4) { request->ttl_v4 = _dns_server_get_conf_ttl(ttl); @@ -1945,7 +1972,7 @@ static int _dns_server_process_answer_A(struct dns_rrs *rrs, struct dns_request } /* add this ip to reqeust */ - if (_dns_ip_address_check_add(request, addr, DNS_T_A) != 0) { + if (_dns_ip_address_check_add(request, cname, addr, DNS_T_A) != 0) { _dns_server_request_release(request); return -1; } @@ -1960,7 +1987,7 @@ static int _dns_server_process_answer_A(struct dns_rrs *rrs, struct dns_request return 0; } -static int _dns_server_process_answer_AAAA(struct dns_rrs *rrs, struct dns_request *request, char *domain, +static int _dns_server_process_answer_AAAA(struct dns_rrs *rrs, struct dns_request *request, char *domain, char *cname, unsigned int result_flag, int ping_timeout) { unsigned char addr[16]; @@ -1992,7 +2019,7 @@ static int _dns_server_process_answer_AAAA(struct dns_rrs *rrs, struct dns_reque } /* if domain is not match */ - if (strncmp(name, domain, DNS_MAX_CNAME_LEN) != 0 && strncmp(request->cname, name, DNS_MAX_CNAME_LEN) != 0) { + if (strncmp(name, domain, DNS_MAX_CNAME_LEN) != 0 && strncmp(cname, name, DNS_MAX_CNAME_LEN) != 0) { _dns_server_request_release(request); return -1; } @@ -2001,6 +2028,10 @@ static int _dns_server_process_answer_AAAA(struct dns_rrs *rrs, struct dns_reque request->has_ipv6 = 1; memcpy(request->ipv6_addr, addr, DNS_RR_AAAA_LEN); request->ttl_v6 = _dns_server_get_conf_ttl(ttl); + if (cname[0] != 0 && request->has_cname == 0) { + request->has_cname = 1; + safe_strncpy(request->cname, cname, DNS_MAX_CNAME_LEN); + } } else { if (ttl < request->ttl_v6) { request->ttl_v6 = _dns_server_get_conf_ttl(ttl); @@ -2017,7 +2048,7 @@ static int _dns_server_process_answer_AAAA(struct dns_rrs *rrs, struct dns_reque } /* add this ip to reqeust */ - if (_dns_ip_address_check_add(request, addr, DNS_T_AAAA) != 0) { + if (_dns_ip_address_check_add(request, cname, addr, DNS_T_AAAA) != 0) { _dns_server_request_release(request); return -1; } @@ -2039,6 +2070,7 @@ static int _dns_server_process_answer(struct dns_request *request, char *domain, { int ttl; char name[DNS_MAX_CNAME_LEN] = {0}; + char cname[DNS_MAX_CNAME_LEN] = {0}; int rr_count; int i = 0; int j = 0; @@ -2068,7 +2100,7 @@ static int _dns_server_process_answer(struct dns_request *request, char *domain, for (i = 0; i < rr_count && rrs; i++, rrs = dns_get_rrs_next(packet, rrs)) { switch (rrs->type) { case DNS_T_A: { - ret = _dns_server_process_answer_A(rrs, request, domain, result_flag, ping_timeout); + ret = _dns_server_process_answer_A(rrs, request, domain, cname, result_flag, ping_timeout); if (ret == -1) { break; } else if (ret == -2) { @@ -2077,7 +2109,7 @@ static int _dns_server_process_answer(struct dns_request *request, char *domain, request->rcode = packet->head.rcode; } break; case DNS_T_AAAA: { - ret = _dns_server_process_answer_AAAA(rrs, request, domain, result_flag, ping_timeout); + ret = _dns_server_process_answer_AAAA(rrs, request, domain, cname, result_flag, ping_timeout); if (ret == -1) { break; } else if (ret == -2) { @@ -2086,17 +2118,13 @@ static int _dns_server_process_answer(struct dns_request *request, char *domain, request->rcode = packet->head.rcode; } break; case DNS_T_NS: { - char cname[DNS_MAX_CNAME_LEN]; - dns_get_CNAME(rrs, name, DNS_MAX_CNAME_LEN, &ttl, cname, DNS_MAX_CNAME_LEN); - tlog(TLOG_DEBUG, "NS: %s ttl:%d cname: %s\n", name, ttl, cname); + char nsname[DNS_MAX_CNAME_LEN]; + dns_get_CNAME(rrs, name, DNS_MAX_CNAME_LEN, &ttl, nsname, DNS_MAX_CNAME_LEN); + tlog(TLOG_DEBUG, "NS: %s ttl:%d nsname: %s\n", name, ttl, nsname); } break; case DNS_T_CNAME: { - char cname[DNS_MAX_CNAME_LEN]; dns_get_CNAME(rrs, name, DNS_MAX_CNAME_LEN, &ttl, cname, DNS_MAX_CNAME_LEN); tlog(TLOG_DEBUG, "name:%s ttl: %d cname: %s\n", name, ttl, cname); - safe_strncpy(request->cname, cname, DNS_MAX_CNAME_LEN); - request->ttl_cname = ttl; - request->has_cname = 1; } break; case DNS_T_SOA: { request->has_soa = 1;