简化dns解析
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@ -38,12 +38,6 @@
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{port, 1366}
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]},
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%% 公共的dns域名解析服务
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{public_dns_servers, [
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{{114, 114, 114, 114}, 53},
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{{8,8,8,8}, 53}
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]},
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{pools, [
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%% mysql连接池配置
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{mysql_sdlan,
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@ -38,12 +38,6 @@
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{port, 1366}
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]},
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%% 公共的dns域名解析服务
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{public_dns_servers, [
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{{114, 114, 114, 114}, 53},
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{{8,8,8,8}, 53}
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]},
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{pools, [
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%% mysql连接池配置
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{mysql_sdlan,
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@ -1,59 +0,0 @@
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-module(dns_cache).
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-include_lib("dns_proxy.hrl").
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-include_lib("dns_erlang/include/dns.hrl").
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-include_lib("dns_erlang/include/dns_records.hrl").
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-include_lib("dns_erlang/include/dns_terms.hrl").
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-export([init/0, lookup/1, insert/2]).
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-define(TABLE, dns_cache).
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init() ->
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ets:new(?TABLE, [named_table, set, public, {keypos, 2}, {read_concurrency, true}]).
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lookup(#dns_query{name = Qname, type = QType, class = QClass}) ->
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Key = {Qname, QType, QClass},
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case ets:lookup(?TABLE, Key) of
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[Cache = #dns_cache{expire_at = ExpireAt}] ->
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Now = os:system_time(second),
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case ExpireAt > Now of
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true ->
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{hit, Cache};
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false ->
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true = ets:delete(?TABLE, Key),
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miss
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end;
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[] ->
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miss
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end.
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insert(#dns_query{name = Qname, type = QType, class = QClass},
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#dns_message{answers = Answers, authority = Authority, additional = Additional, rc = RCode, aa = AA}) ->
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TTLs = lists:foldl(fun(Term, Acc) ->
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case Term of
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#dns_rr{ttl = TTL} ->
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[TTL|Acc];
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_ ->
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Acc
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end
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end, [], Answers ++ Authority ++ Additional),
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case length(TTLs) > 0 of
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true ->
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TTL = lists:min(TTLs),
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ExpireAt = os:system_time(second) + TTL,
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logger:debug("min ttl is: ~p, expire_at: ~p", [TTL, ExpireAt]),
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Key = {Qname, QType, QClass},
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Cache = #dns_cache{
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key = Key,
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answers = Answers,
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authority = Authority,
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additional = Additional,
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rc = RCode,
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flags = #{aa => AA},
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% unix time
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expire_at = ExpireAt
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},
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true = ets:insert(?TABLE, Cache);
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false ->
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ok
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end.
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@ -1,202 +0,0 @@
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%%%-------------------------------------------------------------------
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%%% @author anlicheng
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%%% @copyright (C) 2025, <COMPANY>
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%%% @doc
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%%%
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%%% @end
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%%% Created : 03. 12月 2025 23:00
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%%%-------------------------------------------------------------------
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-module(dns_handler).
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-author("anlicheng").
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-include_lib("dns_erlang/include/dns.hrl").
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-include_lib("pkt/include/pkt.hrl").
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-include("dns_proxy.hrl").
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-export([handle/4]).
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-define(SERVER, ?MODULE).
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-define(RESOLVER_POOL, dns_resolver_pool).
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%% 协议部分
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-define(TCP_PROTOCOL, 6).
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-define(UDP_PROTOCOL, 17).
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-record(state, {}).
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%%%===================================================================
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%%% API
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%%%===================================================================
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handle(Sock, SrcIp, SrcPort, IpPacket) ->
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{#ipv4{saddr = ReqSAddr, daddr = ReqDAddr, p = Protocol}, ReqIpPayload} = pkt:ipv4(IpPacket),
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case Protocol =:= ?UDP_PROTOCOL of
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true ->
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{#udp{sport = ReqSPort, dport = ReqDPort}, UdpPayload} = pkt:udp(ReqIpPayload),
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case resolver(UdpPayload) of
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{ok, DnsResp} ->
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RespIpPacket = build_ip_packet(ReqDAddr, ReqSAddr, ReqDPort, ReqSPort, DnsResp),
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gen_udp:send(Sock, SrcIp, SrcPort, RespIpPacket);
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{error, Reason} ->
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logger:notice("[dns_handler] resolver get error: ~p", [Reason])
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end;
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false ->
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logger:notice("[dns_handler] resolver invalid protocol: ~p", [Protocol])
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end.
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%%%===================================================================
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%%% Internal functions
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%%%===================================================================
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-spec resolver(Packet :: binary()) -> {ok, Resp :: binary()} | {error, Reason :: any()}.
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resolver(Packet) when is_binary(Packet) ->
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resolver0(Packet, dns:decode_message(Packet)).
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resolver0(Packet, QueryMsg = #dns_message{qc = 1, questions = [Question = #dns_query{name = QName, type = QType, class = QClass}|_]}) ->
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%% 查找是否是内置的域名
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case sdlan_hostname_regedit:lookup(QName) of
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{ok, Ip} ->
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Answer = #dns_rr {
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name = QName,
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type = QType,
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class = QClass,
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ttl = 300,
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data = #dns_rrdata_a {
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ip = Ip
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}
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},
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RespMsg = QueryMsg#dns_message{
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qr = true,
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ra = true,
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anc = 1,
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auc = 0,
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adc = 0,
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answers = [Answer],
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authority = [],
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additional = []
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},
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logger:debug("[dns_handler] punchnet inbuilt qnanme: ~p, ip: ~p", [QName, Ip]),
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{ok, dns:encode_message(RespMsg)};
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error ->
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%% 是否命中内部的域名后缀
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EmptyDnsResp = dns:encode_message(build_nxdomain_response(QueryMsg)),
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case sdlan_domain_regedit:maybe_domain(QName) of
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true ->
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logger:debug("[dns_handler] punchnet inbuilt qnanme: ~p, nxdomain", [QName]),
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{ok, EmptyDnsResp};
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false ->
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case dns_cache:lookup(Question) of
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{hit, Cache} ->
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logger:debug("[dns_handler] qname: ~p, hit cache answers: ~p", [QName, Cache#dns_cache.answers]),
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RespMsg = build_response(QueryMsg, Cache),
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{ok, dns:encode_message(RespMsg)};
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miss ->
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case forward_to_upstream(Packet) of
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{ok, Resp} ->
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case dns:decode_message(Resp) of
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RespMsg = #dns_message{answers = Answers} ->
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logger:debug("[dns_handler] get a response answers: ~p", [Answers]),
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dns_cache:insert(Question, RespMsg),
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{ok, Resp};
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Error ->
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logger:debug("[dns_handler] parse reply get error: ~p", [Error]),
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{ok, EmptyDnsResp}
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end;
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{error, Reason} ->
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logger:debug("[dns_handler] parse reply get error: ~p", [Reason]),
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{ok, EmptyDnsResp}
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end
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end
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end
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end;
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resolver0(_, Error) ->
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logger:warning("[dns_handler] decode dns_query get error: ~p", [Error]),
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{error, Error}.
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-spec build_response(QueryMsg :: #dns_message{}, Dns_cache :: #dns_cache{}) -> RespMsg :: #dns_message{}.
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build_response(QueryMsg, #dns_cache{expire_at = ExpireAt, answers = Answers, authority = Authority, additional = Additional, rc = RCode, flags = #{aa := AA}}) ->
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Now = os:system_time(second),
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RemainingTTL = ExpireAt - Now,
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Answers2 = [adjust_ttl(RR, RemainingTTL) || RR <- Answers],
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Authority2 = [adjust_ttl(RR, RemainingTTL) || RR <- Authority],
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Additional2 = [adjust_ttl(RR, RemainingTTL) || RR <- Additional],
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QueryMsg#dns_message{
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qr = true,
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ra = true,
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aa = AA,
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rc = RCode,
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anc = length(Answers2),
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auc = length(Authority2),
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adc = length(Additional2),
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answers = Answers2,
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authority = Authority2,
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additional = Additional2
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}.
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-spec adjust_ttl(RR :: any(), RemainingTTL :: integer()) -> any().
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adjust_ttl(RR = #dns_rr{}, RemainingTTL) ->
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RR#dns_rr{ttl = max(0, RemainingTTL)};
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adjust_ttl(RR, _RemainingTTL) ->
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RR.
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-spec build_nxdomain_response(QueryMsg :: #dns_message{}) -> EmptyResp :: #dns_message{}.
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build_nxdomain_response(QueryMsg) ->
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QueryMsg#dns_message{
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qr = true,
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aa = true,
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ra = true,
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rc = ?DNS_RCODE_NXDOMAIN,
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anc = 0,
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auc = 0,
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adc = 0,
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answers = [],
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authority = [],
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additional = []
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}.
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-spec build_ip_packet(SAddr :: inet:ip4_address(), DAddr :: inet:ip4_address(), SPort :: integer(), DPort :: integer(), Payload :: binary()) -> IpPacket :: binary().
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build_ip_packet(SAddr, DAddr, SPort, DPort, UdpPayload) when is_integer(SPort), is_integer(DPort), is_binary(UdpPayload) ->
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ULen = 8 + byte_size(UdpPayload),
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RespUdpHeader = pkt:udp(#udp{
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sport = SPort,
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dport = DPort,
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ulen = ULen,
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sum = dns_utils:udp_checksum(SAddr, DAddr, SPort, DPort, UdpPayload)
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}),
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IpPayload = <<RespUdpHeader/binary, UdpPayload/binary>>,
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IpPacket0 = #ipv4{
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len = 20 + ULen,
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ttl = 64,
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off = 0,
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mf = 0,
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sum = 0,
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p = ?UDP_PROTOCOL,
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saddr = SAddr,
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daddr = DAddr,
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opt = <<>>
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},
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IpCheckSum = dns_utils:ip_checksum(IpPacket0),
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IpHeader = pkt:ipv4(IpPacket0#ipv4{sum = IpCheckSum}),
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<<IpHeader/binary, IpPayload/binary>>.
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-spec forward_to_upstream(Request :: binary()) -> {ok, Resp :: binary()} | {error, Reason :: any()}.
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forward_to_upstream(Request) ->
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{DnsIp, DnsPort} = select_dns_server(),
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{ok, Socket} = gen_udp:open(0, [binary, {active, true}]),
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ok = gen_udp:send(Socket, DnsIp, DnsPort, Request),
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logger:debug("[dns_resolver] send to: ~p, packet: ~p", [{DnsIp, DnsPort}, Request]),
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receive
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{udp, Socket, DnsIp, DnsPort, Resp} ->
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{ok, Resp}
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after 2000 ->
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{error, timeout}
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end.
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-spec select_dns_server() -> {DnsIp :: inet:ip4_address(), DnsPort :: pos_integer()}.
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select_dns_server() ->
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{ok, DnsServers} = application:get_env(sdlan, public_dns_servers),
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Idx = rand:uniform(length(DnsServers)),
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lists:nth(Idx, DnsServers).
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@ -1,66 +0,0 @@
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%%%-------------------------------------------------------------------
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%%% @author anlicheng
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%%% @copyright (C) 2025, <COMPANY>
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%%% @doc
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%%%
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%%% @end
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%%% Created : 03. 12月 2025 17:29
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%%%-------------------------------------------------------------------
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-module(dns_handler_sup).
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-author("anlicheng").
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-behaviour(supervisor).
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%% API
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-export([start_link/0]).
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%% Supervisor callbacks
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-export([init/1]).
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-export([start_handler/0]).
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-define(SERVER, ?MODULE).
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%%%===================================================================
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%%% API functions
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%%%===================================================================
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%% @doc Starts the supervisor
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-spec(start_link() -> {ok, Pid :: pid()} | ignore | {error, Reason :: term()}).
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start_link() ->
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supervisor:start_link({local, ?SERVER}, ?MODULE, []).
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%%%===================================================================
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%%% Supervisor callbacks
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%%%===================================================================
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%% @private
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%% @doc Whenever a supervisor is started using supervisor:start_link/[2,3],
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%% this function is called by the new process to find out about
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%% restart strategy, maximum restart frequency and child
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%% specifications.
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init([]) ->
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SupFlags = #{strategy => simple_one_for_one, intensity => 0, period => 1},
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Spec = #{
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id => dns_handler,
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start => {'dns_handler', start_link, []},
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restart => temporary,
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shutdown => 2000,
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type => worker,
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modules => ['dns_handler']
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},
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{ok, {SupFlags, [Spec]}}.
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%%%===================================================================
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%%% Internal functions
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%%%===================================================================
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start_handler() ->
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case supervisor:start_child(?MODULE, []) of
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{ok, Pid} ->
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{ok, Pid};
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{error, {already_started, Pid}} ->
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{ok, Pid};
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StartError ->
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StartError
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end.
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@ -1,64 +0,0 @@
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-module(dns_pending_wheel).
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-export([start/0, insert/2, lookup/1, delete/1]).
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-define(TTL, 5).
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-define(TICK_MS, 1000).
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-define(WHEEL_SIZE, (?TTL + 1)).
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%%% =====================================================
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%%% Public API
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%%% =====================================================
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start() ->
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ets:new(dns_pending_data, [ordered_set, public, named_table, {read_concurrency, true}, {write_concurrency, true}]),
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ets:new(dns_pending_wheel, [bag, public, named_table, {read_concurrency, true}, {write_concurrency, true}]),
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start_scanner().
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-spec insert(Key :: any(), Val :: any()) -> ok.
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insert(Key, Val) ->
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Tick = now_tick(),
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Slot = Tick rem ?WHEEL_SIZE,
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ets:insert(dns_pending_data, {Key, {Val, Tick}}),
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ets:insert(dns_pending_wheel, {Slot, {Key, Tick}}),
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ok.
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-spec lookup(Key :: any()) -> [term()].
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lookup(Key) ->
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ets:lookup(dns_pending_data, Key).
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-spec delete(Key :: any()) -> ok.
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delete(Key) ->
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ets:delete(dns_pending_data, Key),
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ok.
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%%% =====================================================
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%%% Internal
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%%% =====================================================
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start_scanner() ->
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{ok, spawn_link(fun tick_loop/0)}.
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%% 当前插入数据是在Tick, 而清理是从 Tick + 1 开始的，没有问题
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tick_loop() ->
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Tick = now_tick(),
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CleanSlot = (Tick + 1) rem ?WHEEL_SIZE,
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spawn(fun() -> clean_slot(CleanSlot) end),
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timer:sleep(?TICK_MS),
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tick_loop().
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clean_slot(Slot) ->
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Items = ets:lookup(dns_pending_wheel, Slot),
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true = ets:delete(dns_pending_wheel, Slot),
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lists:foreach(fun({_, {Key, InsertTick}}) ->
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case ets:lookup(dns_pending_data, Key) of
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[{Key, {_Val, InsertTick}}] ->
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ets:delete(dns_pending_data, Key);
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_ ->
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ok
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end
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end, Items).
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-spec now_tick() -> integer().
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now_tick() ->
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erlang:system_time(second).
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@ -4,138 +4,122 @@
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%%% @doc
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%%%
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%%% @end
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%%% Created : 03. 12月 2025 18:26
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%%% Created : 03. 12月 2025 23:00
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%%%-------------------------------------------------------------------
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-module(dns_resolver).
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-author("anlicheng").
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-include_lib("dns_erlang/include/dns.hrl").
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-include_lib("pkt/include/pkt.hrl").
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-include("dns_proxy.hrl").
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-behaviour(gen_server).
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-export([resolve/1]).
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%% API
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-export([start_link/1]).
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%% gen_server callbacks
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-export([init/1, handle_call/3, handle_cast/2, handle_info/2, terminate/2, code_change/3]).
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-export([forward/5]).
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-define(SERVER, ?MODULE).
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-record(state, {
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socket,
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idx :: integer(),
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dns_servers = []
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}).
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%% 协议部分
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-define(TCP_PROTOCOL, 6).
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-define(UDP_PROTOCOL, 17).
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%%%===================================================================
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%%% API
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%%%===================================================================
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forward(Pid, ReceiverPid, Ref, Request, QueryMsg) ->
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gen_server:cast(Pid, {forward, ReceiverPid, Ref, Request, QueryMsg}).
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%% @doc Spawns the server and registers the local name (unique)
|
||||
-spec(start_link(Args :: list()) ->
|
||||
{ok, Pid :: pid()} | ignore | {error, Reason :: term()}).
|
||||
start_link(Args) when is_list(Args) ->
|
||||
gen_server:start_link(?MODULE, [], []).
|
||||
|
||||
%%%===================================================================
|
||||
%%% gen_server callbacks
|
||||
%%%===================================================================
|
||||
|
||||
%% @private
|
||||
%% @doc Initializes the server
|
||||
-spec(init(Args :: term()) ->
|
||||
{ok, State :: #state{}} | {ok, State :: #state{}, timeout() | hibernate} |
|
||||
{stop, Reason :: term()} | ignore).
|
||||
init([]) ->
|
||||
{ok, DnsServers} = application:get_env(sdlan, public_dns_servers),
|
||||
{ok, Sock} = gen_udp:open(0, [binary, {active, true}]),
|
||||
Idx = erlang:unique_integer([monotonic, positive]),
|
||||
{ok, #state{socket = Sock, idx = Idx, dns_servers = DnsServers}}.
|
||||
|
||||
%% @private
|
||||
%% @doc Handling call messages
|
||||
-spec(handle_call(Request :: term(), From :: {pid(), Tag :: term()},
|
||||
State :: #state{}) ->
|
||||
{reply, Reply :: term(), NewState :: #state{}} |
|
||||
{reply, Reply :: term(), NewState :: #state{}, timeout() | hibernate} |
|
||||
{noreply, NewState :: #state{}} |
|
||||
{noreply, NewState :: #state{}, timeout() | hibernate} |
|
||||
{stop, Reason :: term(), Reply :: term(), NewState :: #state{}} |
|
||||
{stop, Reason :: term(), NewState :: #state{}}).
|
||||
handle_call(_Request, _From, State = #state{}) ->
|
||||
{reply, ok, State}.
|
||||
|
||||
%% @private
|
||||
%% @doc Handling cast messages
|
||||
-spec(handle_cast(Request :: term(), State :: #state{}) ->
|
||||
{noreply, NewState :: #state{}} |
|
||||
{noreply, NewState :: #state{}, timeout() | hibernate} |
|
||||
{stop, Reason :: term(), NewState :: #state{}}).
|
||||
handle_cast({forward, ReceiverPid, Ref, Request, #dns_message{id = TxId, questions = [#dns_query{name = QName, type = QType, class = QClass}|_]}},
|
||||
State = #state{socket = Socket, idx = Idx, dns_servers = DnsServers}) ->
|
||||
|
||||
lists:foreach(fun({DnsIp, DnsPort}) ->
|
||||
ok = gen_udp:send(Socket, DnsIp, DnsPort, Request),
|
||||
Key = {Idx, TxId, DnsIp, DnsPort, QName, QType, QClass},
|
||||
logger:debug("[dns_resolver] key: ~p, send to: ~p, packet: ~p", [Key, {DnsIp, DnsPort}, Request]),
|
||||
dns_pending_wheel:insert(Key, {Ref, ReceiverPid})
|
||||
end, DnsServers),
|
||||
|
||||
{noreply, State}.
|
||||
|
||||
%% @private
|
||||
%% @doc Handling all non call/cast messages
|
||||
-spec(handle_info(Info :: timeout() | term(), State :: #state{}) ->
|
||||
{noreply, NewState :: #state{}} |
|
||||
{noreply, NewState :: #state{}, timeout() | hibernate} |
|
||||
{stop, Reason :: term(), NewState :: #state{}}).
|
||||
handle_info({udp, Socket, TargetIp, TargetPort, Resp}, State = #state{socket = Socket, idx = Idx}) ->
|
||||
try dns:decode_message(Resp) of
|
||||
#dns_message{id = TxId, questions = [#dns_query{name = QName, type = QType, class = QClass}|_]} ->
|
||||
Key = {Idx, TxId, TargetIp, TargetPort, QName, QType, QClass},
|
||||
Records = dns_pending_wheel:lookup(Key),
|
||||
dns_pending_wheel:delete(Key),
|
||||
resolver_reply(Records, Resp);
|
||||
_ ->
|
||||
ok
|
||||
-spec resolve(IpPacket :: binary()) -> {ok, RespIpPacket :: binary()} | {error, Reason :: term()}.
|
||||
resolve(IpPacket) when is_binary(IpPacket) ->
|
||||
try
|
||||
{#ipv4{saddr = ReqSAddr, daddr = ReqDAddr, p = Protocol}, ReqIpPayload} = pkt:ipv4(IpPacket),
|
||||
case Protocol of
|
||||
?UDP_PROTOCOL ->
|
||||
{#udp{sport = ReqSPort, dport = ReqDPort}, UdpPayload} = pkt:udp(ReqIpPayload),
|
||||
DnsQueryMessage = dns:decode_message(UdpPayload),
|
||||
case resolve0(DnsQueryMessage) of
|
||||
{ok, DnsResp} ->
|
||||
RespIpPacket = build_ip_packet(ReqDAddr, ReqSAddr, ReqDPort, ReqSPort, DnsResp),
|
||||
{ok, RespIpPacket};
|
||||
{error, Reason} ->
|
||||
{error, Reason}
|
||||
end;
|
||||
_ ->
|
||||
{error, invalid_packet}
|
||||
end
|
||||
catch error:_ ->
|
||||
ok
|
||||
end,
|
||||
{noreply, State}.
|
||||
|
||||
%% @private
|
||||
%% @doc This function is called by a gen_server when it is about to
|
||||
%% terminate. It should be the opposite of Module:init/1 and do any
|
||||
%% necessary cleaning up. When it returns, the gen_server terminates
|
||||
%% with Reason. The return value is ignored.
|
||||
-spec(terminate(Reason :: (normal | shutdown | {shutdown, term()} | term()),
|
||||
State :: #state{}) -> term()).
|
||||
terminate(_Reason, _State = #state{}) ->
|
||||
ok.
|
||||
|
||||
%% @private
|
||||
%% @doc Convert process state when code is changed
|
||||
-spec(code_change(OldVsn :: term() | {down, term()}, State :: #state{},
|
||||
Extra :: term()) ->
|
||||
{ok, NewState :: #state{}} | {error, Reason :: term()}).
|
||||
code_change(_OldVsn, State = #state{}, _Extra) ->
|
||||
{ok, State}.
|
||||
{error, invalid_packet}
|
||||
end.
|
||||
|
||||
%%%===================================================================
|
||||
%%% Internal functions
|
||||
%%%===================================================================
|
||||
|
||||
-spec resolver_reply(list(), Resp :: binary()) -> no_return().
|
||||
resolver_reply(Records, Resp) when is_binary(Resp) ->
|
||||
lists:foreach(fun({_, {Ref, ReceiverPid}}) ->
|
||||
case is_process_alive(ReceiverPid) of
|
||||
true ->
|
||||
ReceiverPid ! {dns_resolver_reply, Ref, Resp};
|
||||
false ->
|
||||
ok
|
||||
end
|
||||
end, Records).
|
||||
-spec resolve0(Packet :: binary()) -> {ok, Resp :: binary()} | {error, Reason :: any()}.
|
||||
resolve0(QueryMsg = #dns_message{qc = 1, questions = [#dns_query{name = QName, type = QType, class = QClass}|_]}) ->
|
||||
%% 查找是否是内置的域名
|
||||
case sdlan_hostname_regedit:lookup(QName) of
|
||||
{ok, Ip} ->
|
||||
Answer = #dns_rr {
|
||||
name = QName,
|
||||
type = QType,
|
||||
class = QClass,
|
||||
ttl = 300,
|
||||
data = #dns_rrdata_a {
|
||||
ip = Ip
|
||||
}
|
||||
},
|
||||
RespMsg = QueryMsg#dns_message{
|
||||
qr = true,
|
||||
ra = true,
|
||||
anc = 1,
|
||||
auc = 0,
|
||||
adc = 0,
|
||||
answers = [Answer],
|
||||
authority = [],
|
||||
additional = []
|
||||
},
|
||||
logger:debug("[dns_resolver] punchnet inbuilt qnanme: ~p, ip: ~p", [QName, Ip]),
|
||||
{ok, dns:encode_message(RespMsg)};
|
||||
error ->
|
||||
EmptyDnsResp = dns:encode_message(build_nxdomain_response(QueryMsg)),
|
||||
{ok, EmptyDnsResp}
|
||||
end;
|
||||
resolve0(Error) ->
|
||||
{error, Error}.
|
||||
|
||||
-spec build_nxdomain_response(QueryMsg :: #dns_message{}) -> EmptyResp :: #dns_message{}.
|
||||
build_nxdomain_response(QueryMsg) ->
|
||||
QueryMsg#dns_message{
|
||||
qr = true,
|
||||
aa = true,
|
||||
ra = true,
|
||||
rc = ?DNS_RCODE_NXDOMAIN,
|
||||
anc = 0,
|
||||
auc = 0,
|
||||
adc = 0,
|
||||
answers = [],
|
||||
authority = [],
|
||||
additional = []
|
||||
}.
|
||||
|
||||
-spec build_ip_packet(SAddr :: inet:ip4_address(), DAddr :: inet:ip4_address(), SPort :: integer(), DPort :: integer(), Payload :: binary()) -> IpPacket :: binary().
|
||||
build_ip_packet(SAddr, DAddr, SPort, DPort, UdpPayload) when is_integer(SPort), is_integer(DPort), is_binary(UdpPayload) ->
|
||||
ULen = 8 + byte_size(UdpPayload),
|
||||
RespUdpHeader = pkt:udp(#udp{
|
||||
sport = SPort,
|
||||
dport = DPort,
|
||||
ulen = ULen,
|
||||
sum = dns_utils:udp_checksum(SAddr, DAddr, SPort, DPort, UdpPayload)
|
||||
}),
|
||||
IpPayload = <<RespUdpHeader/binary, UdpPayload/binary>>,
|
||||
|
||||
IpPacket0 = #ipv4{
|
||||
len = 20 + ULen,
|
||||
ttl = 64,
|
||||
off = 0,
|
||||
mf = 0,
|
||||
sum = 0,
|
||||
p = ?UDP_PROTOCOL,
|
||||
saddr = SAddr,
|
||||
daddr = DAddr,
|
||||
opt = <<>>
|
||||
},
|
||||
IpCheckSum = dns_utils:ip_checksum(IpPacket0),
|
||||
IpHeader = pkt:ipv4(IpPacket0#ipv4{sum = IpCheckSum}),
|
||||
|
||||
<<IpHeader/binary, IpPayload/binary>>.
|
||||
@ -1,19 +1,130 @@
|
||||
%%%-------------------------------------------------------------------
|
||||
%%% @author anlicheng
|
||||
%%% @copyright (C) 2024, <COMPANY>
|
||||
%%% @doc
|
||||
%%%
|
||||
%%% @end
|
||||
%%% Created : 09. 4月 2024 17:37
|
||||
%%%-------------------------------------------------------------------
|
||||
-module(dns_server).
|
||||
-export([start_link/1, init/1]).
|
||||
-author("anlicheng").
|
||||
-include("sdlan.hrl").
|
||||
-include("sdlan_pb.hrl").
|
||||
|
||||
start_link(Port) when is_integer(Port) ->
|
||||
{ok, spawn_link(?MODULE, init, [Port])}.
|
||||
-behaviour(gen_server).
|
||||
|
||||
init(Port) ->
|
||||
dns_cache:init(),
|
||||
{ok, Sock} = gen_udp:open(Port, [binary, {active, true}]),
|
||||
logger:debug("[dns_server] DNS Forwarder started on UDP port ~p~n", [Port]),
|
||||
loop(Sock).
|
||||
%% API
|
||||
-export([start_link/2]).
|
||||
-export([get_name/1]).
|
||||
|
||||
loop(Sock) ->
|
||||
receive
|
||||
{udp, Sock, Ip, Port, Packet} ->
|
||||
logger:debug("[dns_server] ip: ~p, get a packet: ~p", [{Ip, Port}, Packet]),
|
||||
spawn(fun() -> dns_handler:handle(Sock, Ip, Port, Packet) end),
|
||||
loop(Sock)
|
||||
end.
|
||||
%% gen_server callbacks
|
||||
-export([init/1, handle_call/3, handle_cast/2, handle_info/2, terminate/2, code_change/3]).
|
||||
|
||||
-define(SERVER, ?MODULE).
|
||||
|
||||
-record(state, {
|
||||
socket
|
||||
}).
|
||||
|
||||
%%%===================================================================
|
||||
%%% API
|
||||
%%%===================================================================
|
||||
|
||||
-spec get_name(Id :: integer()) -> atom().
|
||||
get_name(Id) when is_integer(Id) ->
|
||||
list_to_atom("dns_server:" ++ integer_to_list(Id)).
|
||||
|
||||
%% @doc Spawns the server and registers the local name (unique)
|
||||
-spec(start_link(Name :: atom(), Port :: integer()) ->
|
||||
{ok, Pid :: pid()} | ignore | {error, Reason :: term()}).
|
||||
start_link(Name, Port) when is_atom(Name), is_integer(Port) ->
|
||||
gen_server:start_link({local, Name}, ?MODULE, [Port], []).
|
||||
|
||||
%%%===================================================================
|
||||
%%% gen_server callbacks
|
||||
%%%===================================================================
|
||||
|
||||
%% @private
|
||||
%% @doc Initializes the server
|
||||
-spec(init(Args :: term()) ->
|
||||
{ok, State :: #state{}} | {ok, State :: #state{}, timeout() | hibernate} |
|
||||
{stop, Reason :: term()} | ignore).
|
||||
init([Port]) ->
|
||||
%% 需要提高进程的调度优先级
|
||||
erlang:process_flag(priority, high),
|
||||
Opts = [
|
||||
binary,
|
||||
{reuseaddr, true},
|
||||
{reuseport, true},
|
||||
{active, true},
|
||||
{recbuf, 5 * 1024 * 1024},
|
||||
{sndbuf, 5 * 1024 * 1024}
|
||||
],
|
||||
{ok, Socket} = gen_udp:open(Port, Opts),
|
||||
inet_udp:controlling_process(Socket, self()),
|
||||
|
||||
logger:debug("[sdlan_stun] start at port: ~p", [Port]),
|
||||
{ok, #state{socket = Socket}}.
|
||||
|
||||
%% @private
|
||||
%% @doc Handling call messages
|
||||
-spec(handle_call(Request :: term(), From :: {pid(), Tag :: term()},
|
||||
State :: #state{}) ->
|
||||
{reply, Reply :: term(), NewState :: #state{}} |
|
||||
{reply, Reply :: term(), NewState :: #state{}, timeout() | hibernate} |
|
||||
{noreply, NewState :: #state{}} |
|
||||
{noreply, NewState :: #state{}, timeout() | hibernate} |
|
||||
{stop, Reason :: term(), Reply :: term(), NewState :: #state{}} |
|
||||
{stop, Reason :: term(), NewState :: #state{}}).
|
||||
handle_call(_Request, _From, State = #state{}) ->
|
||||
{reply, ok, State}.
|
||||
|
||||
%% @private
|
||||
%% @doc Handling cast messages
|
||||
-spec(handle_cast(Request :: term(), State :: #state{}) ->
|
||||
{noreply, NewState :: #state{}} |
|
||||
{noreply, NewState :: #state{}, timeout() | hibernate} |
|
||||
{stop, Reason :: term(), NewState :: #state{}}).
|
||||
%% 当前node下的转发，基于进程间的通讯
|
||||
handle_cast(_Request, State) ->
|
||||
{noreply, State}.
|
||||
|
||||
%% @private
|
||||
%% @doc Handling all non call/cast messages
|
||||
-spec(handle_info(Info :: timeout() | term(), State :: #state{}) ->
|
||||
{noreply, NewState :: #state{}} |
|
||||
{noreply, NewState :: #state{}, timeout() | hibernate} |
|
||||
{stop, Reason :: term(), NewState :: #state{}}).
|
||||
handle_info({udp, Sock, Ip, Port, IpPacket}, State = #state{socket = Sock}) ->
|
||||
case dns_resolver:resolve(IpPacket) of
|
||||
{ok, RespIpPacket} ->
|
||||
gen_udp:send(Sock, Ip, Port, RespIpPacket);
|
||||
{error, Reason} ->
|
||||
logger:debug("[dns_server] resolve dns query error: ~p", [Reason])
|
||||
end,
|
||||
{noreply, State};
|
||||
handle_info(Info, State) ->
|
||||
logger:error("[sdlan_stun] get a unknown message: ~p, channel will closed", [Info]),
|
||||
{noreply, State}.
|
||||
|
||||
%% @private
|
||||
%% @doc This function is called by a gen_server when it is about to
|
||||
%% terminate. It should be the opposite of Module:init/1 and do any
|
||||
%% necessary cleaning up. When it returns, the gen_server terminates
|
||||
%% with Reason. The return value is ignored.
|
||||
-spec(terminate(Reason :: (normal | shutdown | {shutdown, term()} | term()),
|
||||
State :: #state{}) -> term()).
|
||||
terminate(_Reason, _State = #state{}) ->
|
||||
ok.
|
||||
|
||||
%% @private
|
||||
%% @doc Convert process state when code is changed
|
||||
-spec(code_change(OldVsn :: term() | {down, term()}, State :: #state{},
|
||||
Extra :: term()) ->
|
||||
{ok, NewState :: #state{}} | {error, Reason :: term()}).
|
||||
code_change(_OldVsn, State = #state{}, _Extra) ->
|
||||
{ok, State}.
|
||||
|
||||
%%%===================================================================
|
||||
%%% Internal functions
|
||||
%%%===================================================================
|
||||
@ -3,7 +3,7 @@
|
||||
%% @end
|
||||
%%%-------------------------------------------------------------------
|
||||
|
||||
-module(dns_proxy_sup).
|
||||
-module(dns_server_sup).
|
||||
|
||||
-behaviour(supervisor).
|
||||
|
||||
@ -26,25 +26,18 @@ start_link() ->
|
||||
%% modules => modules()} % optional
|
||||
init([]) ->
|
||||
SupFlags = #{strategy => one_for_one, intensity => 1000, period => 3600},
|
||||
|
||||
Port = 15353,
|
||||
Specs = [
|
||||
AcceptorNum = 10,
|
||||
|
||||
Specs = lists:map(fun(Id) ->
|
||||
Name = dns_server:get_name(Id),
|
||||
#{
|
||||
id => dns_handler_sup,
|
||||
start => {dns_handler_sup, start_link, []},
|
||||
restart => permanent,
|
||||
shutdown => 2000,
|
||||
type => supervisor,
|
||||
modules => ['dns_handler_sup']
|
||||
},
|
||||
#{
|
||||
id => dns_server,
|
||||
start => {dns_server, start_link, [Port]},
|
||||
id => Name,
|
||||
start => {sdlan_stun, start_link, [Name, Port]},
|
||||
restart => permanent,
|
||||
shutdown => 2000,
|
||||
type => worker,
|
||||
modules => ['dns_server']
|
||||
}
|
||||
],
|
||||
|
||||
end, lists:seq(1, AcceptorNum)),
|
||||
{ok, {SupFlags, Specs}}.
|
||||
@ -17,7 +17,6 @@ start(_StartType, _StartArgs) ->
|
||||
%% 启动注册表
|
||||
sdlan_hostname_regedit:init(),
|
||||
sdlan_domain_regedit:init(),
|
||||
dns_pending_wheel:start(),
|
||||
|
||||
%% 权限的数据管理
|
||||
identity_policy_ets:init(),
|
||||
|
||||
Loading…
x
Reference in New Issue
Block a user