简化dns解析

This commit is contained in:
anlicheng 2026-04-13 14:38:24 +08:00
parent d77f61a5ac
commit 59b6607d4c
10 changed files with 236 additions and 552 deletions

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@ -38,12 +38,6 @@
{port, 1366} {port, 1366}
]}, ]},
%% 公共的dns域名解析服务
{public_dns_servers, [
{{114, 114, 114, 114}, 53},
{{8,8,8,8}, 53}
]},
{pools, [ {pools, [
%% mysql连接池配置 %% mysql连接池配置
{mysql_sdlan, {mysql_sdlan,

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@ -38,12 +38,6 @@
{port, 1366} {port, 1366}
]}, ]},
%% 公共的dns域名解析服务
{public_dns_servers, [
{{114, 114, 114, 114}, 53},
{{8,8,8,8}, 53}
]},
{pools, [ {pools, [
%% mysql连接池配置 %% mysql连接池配置
{mysql_sdlan, {mysql_sdlan,

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@ -1,59 +0,0 @@
-module(dns_cache).
-include_lib("dns_proxy.hrl").
-include_lib("dns_erlang/include/dns.hrl").
-include_lib("dns_erlang/include/dns_records.hrl").
-include_lib("dns_erlang/include/dns_terms.hrl").
-export([init/0, lookup/1, insert/2]).
-define(TABLE, dns_cache).
init() ->
ets:new(?TABLE, [named_table, set, public, {keypos, 2}, {read_concurrency, true}]).
lookup(#dns_query{name = Qname, type = QType, class = QClass}) ->
Key = {Qname, QType, QClass},
case ets:lookup(?TABLE, Key) of
[Cache = #dns_cache{expire_at = ExpireAt}] ->
Now = os:system_time(second),
case ExpireAt > Now of
true ->
{hit, Cache};
false ->
true = ets:delete(?TABLE, Key),
miss
end;
[] ->
miss
end.
insert(#dns_query{name = Qname, type = QType, class = QClass},
#dns_message{answers = Answers, authority = Authority, additional = Additional, rc = RCode, aa = AA}) ->
TTLs = lists:foldl(fun(Term, Acc) ->
case Term of
#dns_rr{ttl = TTL} ->
[TTL|Acc];
_ ->
Acc
end
end, [], Answers ++ Authority ++ Additional),
case length(TTLs) > 0 of
true ->
TTL = lists:min(TTLs),
ExpireAt = os:system_time(second) + TTL,
logger:debug("min ttl is: ~p, expire_at: ~p", [TTL, ExpireAt]),
Key = {Qname, QType, QClass},
Cache = #dns_cache{
key = Key,
answers = Answers,
authority = Authority,
additional = Additional,
rc = RCode,
flags = #{aa => AA},
% unix time
expire_at = ExpireAt
},
true = ets:insert(?TABLE, Cache);
false ->
ok
end.

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@ -1,202 +0,0 @@
%%%-------------------------------------------------------------------
%%% @author anlicheng
%%% @copyright (C) 2025, <COMPANY>
%%% @doc
%%%
%%% @end
%%% Created : 03. 12 2025 23:00
%%%-------------------------------------------------------------------
-module(dns_handler).
-author("anlicheng").
-include_lib("dns_erlang/include/dns.hrl").
-include_lib("pkt/include/pkt.hrl").
-include("dns_proxy.hrl").
-export([handle/4]).
-define(SERVER, ?MODULE).
-define(RESOLVER_POOL, dns_resolver_pool).
%%
-define(TCP_PROTOCOL, 6).
-define(UDP_PROTOCOL, 17).
-record(state, {}).
%%%===================================================================
%%% API
%%%===================================================================
handle(Sock, SrcIp, SrcPort, IpPacket) ->
{#ipv4{saddr = ReqSAddr, daddr = ReqDAddr, p = Protocol}, ReqIpPayload} = pkt:ipv4(IpPacket),
case Protocol =:= ?UDP_PROTOCOL of
true ->
{#udp{sport = ReqSPort, dport = ReqDPort}, UdpPayload} = pkt:udp(ReqIpPayload),
case resolver(UdpPayload) of
{ok, DnsResp} ->
RespIpPacket = build_ip_packet(ReqDAddr, ReqSAddr, ReqDPort, ReqSPort, DnsResp),
gen_udp:send(Sock, SrcIp, SrcPort, RespIpPacket);
{error, Reason} ->
logger:notice("[dns_handler] resolver get error: ~p", [Reason])
end;
false ->
logger:notice("[dns_handler] resolver invalid protocol: ~p", [Protocol])
end.
%%%===================================================================
%%% Internal functions
%%%===================================================================
-spec resolver(Packet :: binary()) -> {ok, Resp :: binary()} | {error, Reason :: any()}.
resolver(Packet) when is_binary(Packet) ->
resolver0(Packet, dns:decode_message(Packet)).
resolver0(Packet, QueryMsg = #dns_message{qc = 1, questions = [Question = #dns_query{name = QName, type = QType, class = QClass}|_]}) ->
%%
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_handler] punchnet inbuilt qnanme: ~p, ip: ~p", [QName, Ip]),
{ok, dns:encode_message(RespMsg)};
error ->
%%
EmptyDnsResp = dns:encode_message(build_nxdomain_response(QueryMsg)),
case sdlan_domain_regedit:maybe_domain(QName) of
true ->
logger:debug("[dns_handler] punchnet inbuilt qnanme: ~p, nxdomain", [QName]),
{ok, EmptyDnsResp};
false ->
case dns_cache:lookup(Question) of
{hit, Cache} ->
logger:debug("[dns_handler] qname: ~p, hit cache answers: ~p", [QName, Cache#dns_cache.answers]),
RespMsg = build_response(QueryMsg, Cache),
{ok, dns:encode_message(RespMsg)};
miss ->
case forward_to_upstream(Packet) of
{ok, Resp} ->
case dns:decode_message(Resp) of
RespMsg = #dns_message{answers = Answers} ->
logger:debug("[dns_handler] get a response answers: ~p", [Answers]),
dns_cache:insert(Question, RespMsg),
{ok, Resp};
Error ->
logger:debug("[dns_handler] parse reply get error: ~p", [Error]),
{ok, EmptyDnsResp}
end;
{error, Reason} ->
logger:debug("[dns_handler] parse reply get error: ~p", [Reason]),
{ok, EmptyDnsResp}
end
end
end
end;
resolver0(_, Error) ->
logger:warning("[dns_handler] decode dns_query get error: ~p", [Error]),
{error, Error}.
-spec build_response(QueryMsg :: #dns_message{}, Dns_cache :: #dns_cache{}) -> RespMsg :: #dns_message{}.
build_response(QueryMsg, #dns_cache{expire_at = ExpireAt, answers = Answers, authority = Authority, additional = Additional, rc = RCode, flags = #{aa := AA}}) ->
Now = os:system_time(second),
RemainingTTL = ExpireAt - Now,
Answers2 = [adjust_ttl(RR, RemainingTTL) || RR <- Answers],
Authority2 = [adjust_ttl(RR, RemainingTTL) || RR <- Authority],
Additional2 = [adjust_ttl(RR, RemainingTTL) || RR <- Additional],
QueryMsg#dns_message{
qr = true,
ra = true,
aa = AA,
rc = RCode,
anc = length(Answers2),
auc = length(Authority2),
adc = length(Additional2),
answers = Answers2,
authority = Authority2,
additional = Additional2
}.
-spec adjust_ttl(RR :: any(), RemainingTTL :: integer()) -> any().
adjust_ttl(RR = #dns_rr{}, RemainingTTL) ->
RR#dns_rr{ttl = max(0, RemainingTTL)};
adjust_ttl(RR, _RemainingTTL) ->
RR.
-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>>.
-spec forward_to_upstream(Request :: binary()) -> {ok, Resp :: binary()} | {error, Reason :: any()}.
forward_to_upstream(Request) ->
{DnsIp, DnsPort} = select_dns_server(),
{ok, Socket} = gen_udp:open(0, [binary, {active, true}]),
ok = gen_udp:send(Socket, DnsIp, DnsPort, Request),
logger:debug("[dns_resolver] send to: ~p, packet: ~p", [{DnsIp, DnsPort}, Request]),
receive
{udp, Socket, DnsIp, DnsPort, Resp} ->
{ok, Resp}
after 2000 ->
{error, timeout}
end.
-spec select_dns_server() -> {DnsIp :: inet:ip4_address(), DnsPort :: pos_integer()}.
select_dns_server() ->
{ok, DnsServers} = application:get_env(sdlan, public_dns_servers),
Idx = rand:uniform(length(DnsServers)),
lists:nth(Idx, DnsServers).

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@ -1,66 +0,0 @@
%%%-------------------------------------------------------------------
%%% @author anlicheng
%%% @copyright (C) 2025, <COMPANY>
%%% @doc
%%%
%%% @end
%%% Created : 03. 12 2025 17:29
%%%-------------------------------------------------------------------
-module(dns_handler_sup).
-author("anlicheng").
-behaviour(supervisor).
%% API
-export([start_link/0]).
%% Supervisor callbacks
-export([init/1]).
-export([start_handler/0]).
-define(SERVER, ?MODULE).
%%%===================================================================
%%% API functions
%%%===================================================================
%% @doc Starts the supervisor
-spec(start_link() -> {ok, Pid :: pid()} | ignore | {error, Reason :: term()}).
start_link() ->
supervisor:start_link({local, ?SERVER}, ?MODULE, []).
%%%===================================================================
%%% Supervisor callbacks
%%%===================================================================
%% @private
%% @doc Whenever a supervisor is started using supervisor:start_link/[2,3],
%% this function is called by the new process to find out about
%% restart strategy, maximum restart frequency and child
%% specifications.
init([]) ->
SupFlags = #{strategy => simple_one_for_one, intensity => 0, period => 1},
Spec = #{
id => dns_handler,
start => {'dns_handler', start_link, []},
restart => temporary,
shutdown => 2000,
type => worker,
modules => ['dns_handler']
},
{ok, {SupFlags, [Spec]}}.
%%%===================================================================
%%% Internal functions
%%%===================================================================
start_handler() ->
case supervisor:start_child(?MODULE, []) of
{ok, Pid} ->
{ok, Pid};
{error, {already_started, Pid}} ->
{ok, Pid};
StartError ->
StartError
end.

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@ -1,64 +0,0 @@
-module(dns_pending_wheel).
-export([start/0, insert/2, lookup/1, delete/1]).
-define(TTL, 5).
-define(TICK_MS, 1000).
-define(WHEEL_SIZE, (?TTL + 1)).
%%% =====================================================
%%% Public API
%%% =====================================================
start() ->
ets:new(dns_pending_data, [ordered_set, public, named_table, {read_concurrency, true}, {write_concurrency, true}]),
ets:new(dns_pending_wheel, [bag, public, named_table, {read_concurrency, true}, {write_concurrency, true}]),
start_scanner().
-spec insert(Key :: any(), Val :: any()) -> ok.
insert(Key, Val) ->
Tick = now_tick(),
Slot = Tick rem ?WHEEL_SIZE,
ets:insert(dns_pending_data, {Key, {Val, Tick}}),
ets:insert(dns_pending_wheel, {Slot, {Key, Tick}}),
ok.
-spec lookup(Key :: any()) -> [term()].
lookup(Key) ->
ets:lookup(dns_pending_data, Key).
-spec delete(Key :: any()) -> ok.
delete(Key) ->
ets:delete(dns_pending_data, Key),
ok.
%%% =====================================================
%%% Internal
%%% =====================================================
start_scanner() ->
{ok, spawn_link(fun tick_loop/0)}.
%% Tick, Tick + 1
tick_loop() ->
Tick = now_tick(),
CleanSlot = (Tick + 1) rem ?WHEEL_SIZE,
spawn(fun() -> clean_slot(CleanSlot) end),
timer:sleep(?TICK_MS),
tick_loop().
clean_slot(Slot) ->
Items = ets:lookup(dns_pending_wheel, Slot),
true = ets:delete(dns_pending_wheel, Slot),
lists:foreach(fun({_, {Key, InsertTick}}) ->
case ets:lookup(dns_pending_data, Key) of
[{Key, {_Val, InsertTick}}] ->
ets:delete(dns_pending_data, Key);
_ ->
ok
end
end, Items).
-spec now_tick() -> integer().
now_tick() ->
erlang:system_time(second).

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@ -4,138 +4,122 @@
%%% @doc %%% @doc
%%% %%%
%%% @end %%% @end
%%% Created : 03. 12 2025 18:26 %%% Created : 03. 12 2025 23:00
%%%------------------------------------------------------------------- %%%-------------------------------------------------------------------
-module(dns_resolver). -module(dns_resolver).
-author("anlicheng"). -author("anlicheng").
-include_lib("dns_erlang/include/dns.hrl"). -include_lib("dns_erlang/include/dns.hrl").
-include_lib("pkt/include/pkt.hrl").
-include("dns_proxy.hrl").
-behaviour(gen_server). -export([resolve/1]).
%% API %%
-export([start_link/1]). -define(TCP_PROTOCOL, 6).
-define(UDP_PROTOCOL, 17).
%% gen_server callbacks
-export([init/1, handle_call/3, handle_cast/2, handle_info/2, terminate/2, code_change/3]).
-export([forward/5]).
-define(SERVER, ?MODULE).
-record(state, {
socket,
idx :: integer(),
dns_servers = []
}).
%%%=================================================================== %%%===================================================================
%%% API %%% API
%%%=================================================================== %%%===================================================================
forward(Pid, ReceiverPid, Ref, Request, QueryMsg) -> -spec resolve(IpPacket :: binary()) -> {ok, RespIpPacket :: binary()} | {error, Reason :: term()}.
gen_server:cast(Pid, {forward, ReceiverPid, Ref, Request, QueryMsg}). resolve(IpPacket) when is_binary(IpPacket) ->
try
%% @doc Spawns the server and registers the local name (unique) {#ipv4{saddr = ReqSAddr, daddr = ReqDAddr, p = Protocol}, ReqIpPayload} = pkt:ipv4(IpPacket),
-spec(start_link(Args :: list()) -> case Protocol of
{ok, Pid :: pid()} | ignore | {error, Reason :: term()}). ?UDP_PROTOCOL ->
start_link(Args) when is_list(Args) -> {#udp{sport = ReqSPort, dport = ReqDPort}, UdpPayload} = pkt:udp(ReqIpPayload),
gen_server:start_link(?MODULE, [], []). DnsQueryMessage = dns:decode_message(UdpPayload),
case resolve0(DnsQueryMessage) of
%%%=================================================================== {ok, DnsResp} ->
%%% gen_server callbacks RespIpPacket = build_ip_packet(ReqDAddr, ReqSAddr, ReqDPort, ReqSPort, DnsResp),
%%%=================================================================== {ok, RespIpPacket};
{error, Reason} ->
%% @private {error, Reason}
%% @doc Initializes the server end;
-spec(init(Args :: term()) -> _ ->
{ok, State :: #state{}} | {ok, State :: #state{}, timeout() | hibernate} | {error, invalid_packet}
{stop, Reason :: term()} | ignore). end
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
catch error:_ -> catch error:_ ->
ok {error, invalid_packet}
end, 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}.
%%%=================================================================== %%%===================================================================
%%% Internal functions %%% Internal functions
%%%=================================================================== %%%===================================================================
-spec resolver_reply(list(), Resp :: binary()) -> no_return(). -spec resolve0(Packet :: binary()) -> {ok, Resp :: binary()} | {error, Reason :: any()}.
resolver_reply(Records, Resp) when is_binary(Resp) -> resolve0(QueryMsg = #dns_message{qc = 1, questions = [#dns_query{name = QName, type = QType, class = QClass}|_]}) ->
lists:foreach(fun({_, {Ref, ReceiverPid}}) -> %%
case is_process_alive(ReceiverPid) of case sdlan_hostname_regedit:lookup(QName) of
true -> {ok, Ip} ->
ReceiverPid ! {dns_resolver_reply, Ref, Resp}; Answer = #dns_rr {
false -> name = QName,
ok type = QType,
end class = QClass,
end, Records). 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>>.

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@ -1,19 +1,130 @@
%%%-------------------------------------------------------------------
%%% @author anlicheng
%%% @copyright (C) 2024, <COMPANY>
%%% @doc
%%%
%%% @end
%%% Created : 09. 4 2024 17:37
%%%-------------------------------------------------------------------
-module(dns_server). -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) -> -behaviour(gen_server).
{ok, spawn_link(?MODULE, init, [Port])}.
init(Port) -> %% API
dns_cache:init(), -export([start_link/2]).
{ok, Sock} = gen_udp:open(Port, [binary, {active, true}]), -export([get_name/1]).
logger:debug("[dns_server] DNS Forwarder started on UDP port ~p~n", [Port]),
loop(Sock).
loop(Sock) -> %% gen_server callbacks
receive -export([init/1, handle_call/3, handle_cast/2, handle_info/2, terminate/2, code_change/3]).
{udp, Sock, Ip, Port, Packet} ->
logger:debug("[dns_server] ip: ~p, get a packet: ~p", [{Ip, Port}, Packet]), -define(SERVER, ?MODULE).
spawn(fun() -> dns_handler:handle(Sock, Ip, Port, Packet) end),
loop(Sock) -record(state, {
end. 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]) ->
%%
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{}}).
%% node下的转发
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
%%%===================================================================

View File

@ -3,7 +3,7 @@
%% @end %% @end
%%%------------------------------------------------------------------- %%%-------------------------------------------------------------------
-module(dns_proxy_sup). -module(dns_server_sup).
-behaviour(supervisor). -behaviour(supervisor).
@ -26,25 +26,18 @@ start_link() ->
%% modules => modules()} % optional %% modules => modules()} % optional
init([]) -> init([]) ->
SupFlags = #{strategy => one_for_one, intensity => 1000, period => 3600}, SupFlags = #{strategy => one_for_one, intensity => 1000, period => 3600},
Port = 15353, Port = 15353,
Specs = [ AcceptorNum = 10,
Specs = lists:map(fun(Id) ->
Name = dns_server:get_name(Id),
#{ #{
id => dns_handler_sup, id => Name,
start => {dns_handler_sup, start_link, []}, start => {sdlan_stun, start_link, [Name, Port]},
restart => permanent,
shutdown => 2000,
type => supervisor,
modules => ['dns_handler_sup']
},
#{
id => dns_server,
start => {dns_server, start_link, [Port]},
restart => permanent, restart => permanent,
shutdown => 2000, shutdown => 2000,
type => worker, type => worker,
modules => ['dns_server'] modules => ['dns_server']
} }
], end, lists:seq(1, AcceptorNum)),
{ok, {SupFlags, Specs}}. {ok, {SupFlags, Specs}}.

View File

@ -17,7 +17,6 @@ start(_StartType, _StartArgs) ->
%% %%
sdlan_hostname_regedit:init(), sdlan_hostname_regedit:init(),
sdlan_domain_regedit:init(), sdlan_domain_regedit:init(),
dns_pending_wheel:start(),
%% %%
identity_policy_ets:init(), identity_policy_ets:init(),