1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
|
%%
%% %CopyrightBegin%
%%
%% Copyright Ericsson AB 2007-2010. All Rights Reserved.
%%
%% The contents of this file are subject to the Erlang Public License,
%% Version 1.1, (the "License"); you may not use this file except in
%% compliance with the License. You should have received a copy of the
%% Erlang Public License along with this software. If not, it can be
%% retrieved online at http://www.erlang.org/.
%%
%% Software distributed under the License is distributed on an "AS IS"
%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
%% the License for the specific language governing rights and limitations
%% under the License.
%%
%% %CopyrightEnd%
%%
%% SCTP protocol contribution by Leonid Timochouk and Serge Aleynikov.
%% See also: $ERL_TOP/lib/kernel/AUTHORS
%%
-module(inet_sctp).
%% This module provides functions for communicating with
%% sockets using the SCTP protocol. The implementation assumes that
%% the OS kernel supports SCTP providing user-level SCTP Socket API:
%% http://tools.ietf.org/html/draft-ietf-tsvwg-sctpsocket-13
-include("inet_sctp.hrl").
-include("inet_int.hrl").
-define(FAMILY, inet).
-export([getserv/1,getaddr/1,getaddr/2,translate_ip/1]).
-export([open/1,close/1,listen/2,connect/5,sendmsg/3,send/4,recv/2]).
getserv(Port) when is_integer(Port) -> {ok, Port};
getserv(Name) when is_atom(Name) ->
inet:getservbyname(Name, sctp);
getserv(_) ->
{error,einval}.
getaddr(Address) ->
inet:getaddr(Address, ?FAMILY).
getaddr(Address, Timer) ->
inet:getaddr_tm(Address, ?FAMILY, Timer).
translate_ip(IP) ->
inet:translate_ip(IP, ?FAMILY).
open(Opts) ->
case inet:sctp_options(Opts, ?MODULE) of
{ok,#sctp_opts{fd=Fd,ifaddr=Addr,port=Port,opts=SOs}} ->
inet:open(Fd, Addr, Port, SOs, sctp, ?FAMILY, ?MODULE);
Error -> Error
end.
close(S) ->
prim_inet:close(S).
listen(S, Flag) ->
prim_inet:listen(S, Flag).
%% A non-blocking connect is implemented when the initial call is to
%% gen_sctp:connect_init which passes the value nowait as the Timer
connect(S, Addr, Port, Opts, Timer) ->
case prim_inet:chgopts(S, Opts) of
ok ->
case prim_inet:getopt(S, active) of
{ok,Active} ->
Timeout = if Timer =:= nowait ->
infinity; %% don't start driver timer in inet_drv
true ->
inet:timeout(Timer)
end,
case prim_inet:connect(S, Addr, Port, Timeout) of
ok when Timer =/= nowait ->
connect_get_assoc(S, Addr, Port, Active, Timer);
OkOrErr1 -> OkOrErr1
end;
Err2 -> Err2
end;
Err3 -> Err3
end.
%% XXX race condition problem
%%
%% If an incoming #sctp_assoc_change{} arrives after
%% prim_inet:getopt(S, alive) above but before the
%% #sctp_assoc_change{state=comm_up} originating from
%% prim_inet:connect(S, Addr, Port, Timeout) above,
%% connect_get_assoc/5 below mistakes it for an invalid response
%% for a socket in {active,false} or {active,once} modes.
%%
%% In {active,true} mode the window of time for the race is smaller,
%% but it is possible and also it is a blocking connect that is
%% implemented even for {active,true}, and that may be a
%% shortcoming.
connect_get_assoc(S, Addr, Port, false, Timer) ->
case recv(S, inet:timeout(Timer)) of
{ok, {Addr, Port, [], #sctp_assoc_change{state=St}=Ev}} ->
if St =:= comm_up ->
%% Yes, successfully connected, return the whole
%% sctp_assoc_change event (containing, in particular,
%% the AssocID).
%% NB: we consider the connection to be successful
%% even if the number of OutStreams is not the same
%% as requested by the user:
{ok,Ev};
true ->
{error,Ev}
end;
%% Any other event: Error:
{ok, Msg} ->
{error, Msg};
{error,_}=Error ->
Error
end;
connect_get_assoc(S, Addr, Port, Active, Timer) ->
Timeout = inet:timeout(Timer),
receive
{sctp,S,Addr,Port,{[],#sctp_assoc_change{state=St}=Ev}} ->
case Active of
once ->
prim_inet:setopt(S, active, once);
_ -> ok
end,
if St =:= comm_up ->
{ok,Ev};
true ->
{error,Ev}
end
after Timeout ->
{error,timeout}
end.
sendmsg(S, SRI, Data) ->
prim_inet:sendmsg(S, SRI, Data).
send(S, AssocId, Stream, Data) ->
case prim_inet:getopts(
S,
[{sctp_default_send_param,#sctp_sndrcvinfo{assoc_id=AssocId}}]) of
{ok,
[{sctp_default_send_param,
#sctp_sndrcvinfo{
flags=Flags, context=Context, ppid=PPID, timetolive=TTL}}]} ->
prim_inet:sendmsg(
S,
#sctp_sndrcvinfo{
flags=Flags, context=Context, ppid=PPID, timetolive=TTL,
assoc_id=AssocId, stream=Stream},
Data);
_ ->
prim_inet:sendmsg(
S, #sctp_sndrcvinfo{assoc_id=AssocId, stream=Stream}, Data)
end.
recv(S, Timeout) ->
prim_inet:recvfrom(S, 0, Timeout).
|
