From 86902d2e3415666246dae0286262e43923f58532 Mon Sep 17 00:00:00 2001 From: Nick Peng Date: Sun, 6 Sep 2020 15:21:37 +0800 Subject: [PATCH] serve-expired: support config reply ttl --- ReadMe.md | 1 + ReadMe_en.md | 1 + etc/smartdns/smartdns.conf | 4 ++++ src/dns_conf.c | 2 ++ src/dns_conf.h | 1 + src/dns_server.c | 14 ++++++++++++-- 6 files changed, 21 insertions(+), 2 deletions(-) diff --git a/ReadMe.md b/ReadMe.md index 3df12a1..21d1e05 100644 --- a/ReadMe.md +++ b/ReadMe.md @@ -537,6 +537,7 @@ https://github.com/pymumu/smartdns/releases |prefetch-domain|域名预先获取功能|no|[yes\|no]|prefetch-domain yes |serve-expired|过期缓存服务功能|no|[yes\|no]，开启此功能后，如果有请求时尝试回应TTL为0的过期记录，并并发查询记录，以避免查询等待|serve-expired yes |serve-expired-ttl|过期缓存服务最长超时时间|0|秒，0：表示停用超时，> 0表示指定的超时的秒数|serve-expired-ttl 0 +|serve-expired-reply-ttl|回应的过期缓存TTL|5|秒，0：表示停用超时，> 0表示指定的超时的秒数|serve-expired-reply-ttl 30 |dualstack-ip-selection|双栈IP优选|no|[yes\|no]|dualstack-ip-selection yes |dualstack-ip-selection-threshold|双栈IP优选阈值|30ms|毫秒|dualstack-ip-selection-threshold [0-1000] |ca-file|证书文件|/etc/ssl/certs/ca-certificates.crt|路径|ca-file /etc/ssl/certs/ca-certificates.crt diff --git a/ReadMe_en.md b/ReadMe_en.md index 409e6fa..13343e8 100755 --- a/ReadMe_en.md +++ b/ReadMe_en.md @@ -531,6 +531,7 @@ Note: Merlin firmware is derived from ASUS firmware and can theoretically be use |prefetch-domain|domain prefetch feature|no|[yes\|no]|prefetch-domain yes |serve-expired|Cache serve expired feature|no|[yes\|no], Attempts to serve old responses from cache with a TTL of 0 in the response without waiting for the actual resolution to finish.|serve-expired yes |serve-expired-ttl|Cache serve expired limite TTL|0|second，0：disable，> 0 seconds after expiration|serve-expired-ttl 0 +|serve-expired-reply-ttl|TTL value to use when replying with expired data|5|second，0：disable，> 0 seconds after expiration|serve-expired-reply-ttl 30 |dualstack-ip-selection|Dualstack ip selection|no|[yes\|no]|dualstack-ip-selection yes |dualstack-ip-selection-threshold|Dualstack ip select threadhold|30ms|millisecond|dualstack-ip-selection-threshold [0-1000] |ca-file|certificate file|/etc/ssl/certs/ca-certificates.crt|path|ca-file /etc/ssl/certs/ca-certificates.crt diff --git a/etc/smartdns/smartdns.conf b/etc/smartdns/smartdns.conf index dec24b1..018a3f9 100644 --- a/etc/smartdns/smartdns.conf +++ b/etc/smartdns/smartdns.conf @@ -58,6 +58,10 @@ cache-size 4096 # serve-expired-ttl [num] # serve-expired-ttl 0 +# reply TTL value to use when replying with expired data +# serve-expired-reply-ttl [num] +# serve-expired-reply-ttl 30 + # List of hosts that supply bogus NX domain results # bogus-nxdomain [ip/subnet] diff --git a/src/dns_conf.c b/src/dns_conf.c index bd9641c..8f9f408 100644 --- a/src/dns_conf.c +++ b/src/dns_conf.c @@ -50,6 +50,7 @@ int dns_conf_cachesize = DEFAULT_DNS_CACHE_SIZE; int dns_conf_prefetch = 0; int dns_conf_serve_expired = 0; int dns_conf_serve_expired_ttl = 0; +int dns_conf_serve_expired_reply_ttl = 5; /* upstream servers */ struct dns_servers dns_conf_servers[DNS_MAX_SERVERS]; @@ -1366,6 +1367,7 @@ static struct config_item _config_item[] = { CONF_YESNO("prefetch-domain", &dns_conf_prefetch), CONF_YESNO("serve-expired", &dns_conf_serve_expired), CONF_INT("serve-expired-ttl", &dns_conf_serve_expired_ttl, 0, CONF_INT_MAX), + CONF_INT("serve-expired-reply-ttl", &dns_conf_serve_expired_reply_ttl, 0, CONF_INT_MAX), CONF_YESNO("dualstack-ip-selection", &dns_conf_dualstack_ip_selection), CONF_INT("dualstack-ip-selection-threshold", &dns_conf_dualstack_ip_selection_threshold, 0, 1000), CONF_CUSTOM("log-level", _config_log_level, NULL), diff --git a/src/dns_conf.h b/src/dns_conf.h index e8aef86..95aaa78 100644 --- a/src/dns_conf.h +++ b/src/dns_conf.h @@ -205,6 +205,7 @@ extern int dns_conf_cachesize; extern int dns_conf_prefetch; extern int dns_conf_serve_expired; extern int dns_conf_serve_expired_ttl; +extern int dns_conf_serve_expired_reply_ttl; extern struct dns_servers dns_conf_servers[DNS_MAX_SERVERS]; extern int dns_conf_server_num; diff --git a/src/dns_server.c b/src/dns_server.c index 455e564..884601a 100644 --- a/src/dns_server.c +++ b/src/dns_server.c @@ -2264,6 +2264,16 @@ static void _dns_server_process_speed_check_rule(struct dns_request *request) request->check_order_list = check_order; } +static int _dns_server_get_expired_ttl_reply(struct dns_cache *dns_cache) +{ + int ttl = dns_cache_get_ttl(dns_cache); + if (ttl > 0) { + return ttl; + } + + return dns_conf_serve_expired_reply_ttl; +} + static int _dns_server_process_cache_addr(struct dns_request *request, struct dns_cache *dns_cache) { struct dns_cache_addr *cache_addr = (struct dns_cache_addr *)dns_cache_get_data(dns_cache); @@ -2275,12 +2285,12 @@ static int _dns_server_process_cache_addr(struct dns_request *request, struct dn switch (request->qtype) { case DNS_T_A: memcpy(request->ipv4_addr, cache_addr->addr_data.ipv4_addr, DNS_RR_A_LEN); - request->ttl_v4 = dns_cache_get_ttl(dns_cache); + request->ttl_v4 = _dns_server_get_expired_ttl_reply(dns_cache); request->has_ipv4 = 1; break; case DNS_T_AAAA: memcpy(request->ipv6_addr, cache_addr->addr_data.ipv6_addr, DNS_RR_AAAA_LEN); - request->ttl_v6 = dns_cache_get_ttl(dns_cache); + request->ttl_v6 = _dns_server_get_expired_ttl_reply(dns_cache); request->has_ipv6 = 1; break; default: