modules/erl/smtp.erl

   1 %    -*- Erlang -*-
   2 %    File:      smtp.erl  (~jb/work/yaws/applications/mail/src/smtp.erl)
   3 %    Author:    Johan Bevemyr
   4 %    Created:   Tue Feb 24 23:15:59 2004
   5 %    Purpose:
   6
   7 -module('smtp').
   8 -author('jb@bevemyr.com').
   9
  10 -export([send/6]).
  11
  12 %% Example
  13
  14 %
  15 % smtp:send("mail.bevemyr.com", "jb@bevemyr.com",
  16 %          ["katrin@bevemyr.com","jb@bevemyr.com"],
  17 %          "Test Subject",
  18 %          "My Message", [{"file1.txt","text/plain","hej hopp igen"}]).
  19 %
  20
  21
  22 send(Server, From, To, Subject, Message, Attached) ->
  23     {ok, Port} = smtp_init(Server, From, To),
  24     Boundary="--Next_Part("++boundary_date()++")--",
  25     CommonHeaders =
  26         [mail_header("To: ", To),
  27          mail_header("From: ", From),
  28          mail_header("Subject: ", Subject)],
  29     Headers = case Attached of
  30                   [] ->
  31                       [mail_header("Content-Type: ", "text/plain"),
  32                        mail_header("Content-Transfer-Encoding: ", "8bit")];
  33                   _ ->
  34                       [mail_header("Mime-Version: ", "1.0"),
  35                        mail_header("Content-Type: ",
  36                                    "Multipart/Mixed;\r\n boundary=\""++
  37                                    Boundary++"\""),
  38                        mail_header("Content-Transfer-Encoding: ", "8bit")]
  39               end,
  40     smtp_send_part(Port, [CommonHeaders, Headers, "\r\n"]),
  41     case Attached of
  42         [] ->
  43             ok;
  44         _ ->
  45             smtp_send_part(Port, ["--",Boundary,"\r\n",
  46                                   mail_header("Content-Type: ",
  47                                               "Text/Plain; charset=us-ascii"),
  48                                   mail_header("Content-Transfer-Encoding: ",
  49                                               "8bit"),
  50                                   "\r\n"])
  51     end,
  52     smtp_send_message(Port, Message),
  53     case Attached of
  54         [] ->
  55             smtp_send_part(Port, ["\r\n.\r\n"]),
  56             smtp_close(Port);
  57         Files ->
  58             smtp_send_attachments(Port, Boundary, Files),
  59             smtp_send_part(Port, ["\r\n.\r\n"]),
  60             smtp_close(Port)
  61     end.
  62
  63
  64 smtp_send_attachments(Port, Boundary, []) ->
  65     smtp_send_part(Port, ["\r\n--",Boundary,"--\r\n"]);
  66 smtp_send_attachments(Port, Boundary, [{FileName,ContentType,Data}|Rest]) ->
  67     smtp_send_part(Port, ["\r\n--",Boundary,"\r\n",
  68                           mail_header("Content-Type: ", ContentType),
  69                           mail_header("Content-Transfer-Encoding: ",
  70                                       "base64"),
  71                           mail_header("Content-Disposition: ",
  72                                       "attachment; filename=\""++
  73                                       FileName++"\""),
  74                           "\r\n"
  75                          ]),
  76     smtp_send_b64(Port, Data),
  77     smtp_send_attachments(Port, Boundary, Rest).
  78
  79
  80 smtp_send_b64(Port, Data) ->
  81     B64 = str2b64_final(Data),
  82     gen_tcp:send(Port, B64).
  83
  84 boundary_date() ->
  85     dat2str_boundary(calendar:local_time()).
  86
  87 dat2str_boundary({{Y, Mo, D}, {H, M, S}}) ->
  88     lists:flatten(
  89       io_lib:format("~s_~2.2.0w_~s_~w_~2.2.0w:~2.2.0w:~2.2.0w_~w",
  90                     [weekday(Y,Mo,D), D, int_to_mt(Mo),
  91                      Y,H,M,S,random:uniform(5000)])).
  92
  93
  94 smtp_init(Server, From, Recipients) ->
  95     {ok, Port} = gen_tcp:connect(Server, 25, [{active, false},
  96                                               {reuseaddr,true},
  97                                               binary]),
  98     smtp_expect(220, Port, "SMTP server does not respond"),
  99     smtp_put( smtp_from(From), Port ),
 100     smtp_expect(250, Port, "Sender not accepted by mail server"),
 101     send_recipients(Recipients, Port),
 102     smtp_put("DATA", Port),
 103     smtp_expect(354, Port, "Message not accepted by mail server."),
 104     {ok, Port}.
 105
 106
 107 smtp_close(Port) ->
 108     smtp_put(".", Port),
 109     smtp_expect(250, Port, "Message not accepted by mail server."),
 110     gen_tcp:close(Port),
 111     ok.
 112
 113 smtp_send_part(Port, Data) ->
 114     gen_tcp:send(Port, Data).
 115
 116 smtp_send_message(Port, Data) ->
 117     {_LastNL, Escaped} = dot_escape(Data, true),
 118     gen_tcp:send(Port, Escaped).
 119
 120 send_recipients( Recipients, Port ) ->
 121         Fun = fun (R) ->
 122                         smtp_put( smtp_recipient(R), Port),
 123                         smtp_expect(250, Port, io_lib:format("Recipient ~s not accepted.",[R]))
 124                 end,
 125         lists:foreach( Fun, Recipients ).
 126
 127 smtp_put(Message, Port) ->
 128     gen_tcp:send(Port, [Message,"\r\n"]).
 129
 130 smtp_expect(Code, Port, ErrorMsg) ->
 131     smtp_expect(Code, Port, [], ErrorMsg).
 132
 133 smtp_expect(Code, Port, Acc, ErrorMsg) ->
 134     Res = gen_tcp:recv(Port, 0, 15000),
 135     case Res of
 136         {ok, Bin} ->
 137             NAcc = Acc++binary_to_list(Bin),
 138             case string:chr(NAcc, $\n) of
 139                 0 ->
 140                     smtp_expect(Code, Port, NAcc, ErrorMsg);
 141                 _N ->
 142                     ResponseCode = to_int(NAcc),
 143                     if
 144                         ResponseCode == Code -> ok;
 145                         true -> throw({error, ErrorMsg})
 146                     end
 147             end;
 148         Err ->
 149             throw({error, Err})
 150     end.
 151
 152 %% add smtp from prelude. add <> around address (if needed)
 153 smtp_from( Address ) ->
 154         lists:append( "MAIL FROM: ", add_angle_brackets( Address ) ).
 155
 156 %% add smtp recipients prelude. add <> around address (if needed)
 157 smtp_recipient( Address ) ->
 158         lists:append( "RCPT TO: ", add_angle_brackets( Address ) ).
 159
 160 %% make sure the address has <> around itself
 161 add_angle_brackets( Address ) ->
 162         add_angle_bracket_start( add_angle_bracket_close(Address) ).
 163
 164 add_angle_bracket_start( [$<|T] ) -> [$<|T];
 165 add_angle_bracket_start( Address ) -> [$<|Address].
 166
 167 %% add > at the end of address, if it is not present
 168 add_angle_bracket_close( Address ) ->
 169         case lists:reverse( Address ) of
 170         [$>|_T] -> Address;
 171         Reversed -> lists:reverse( [$>|Reversed] )
 172         end.
 173
 174 %% Add an . at all lines starting with a dot.
 175
 176 dot_escape(Data, NL) ->
 177     dot_escape(Data, NL, []).
 178
 179 dot_escape([], NL, Acc) ->
 180     {NL, lists:reverse(Acc)};
 181 dot_escape([$.|Rest], true, Acc) ->
 182     dot_escape(Rest, false, [$.,$.|Acc]);
 183 dot_escape([$\n|Rest], _, Acc) ->
 184     dot_escape(Rest, true, [$\n|Acc]);
 185 dot_escape([C|Rest], _, Acc) ->
 186     dot_escape(Rest, false, [C|Acc]).
 187
 188 %%
 189
 190 %dot_unescape(Data) ->
 191 %    {_,Dt} = dot_unescape(Data, true, []),
 192 %    Dt.
 193 %
 194 %dot_unescape([], NL, Acc) ->
 195 %    {NL, lists:reverse(Acc)};
 196 %dot_unescape([$.|Rest], true, Acc) ->
 197 %    dot_unescape(Rest, false, Acc);
 198 %dot_unescape([$\n|Rest], _, Acc) ->
 199 %    dot_unescape(Rest, true, [$\n|Acc]);
 200 %dot_unescape([L|Rest], NL, Acc) when list(L) ->
 201 %    {NL2, L2} = dot_unescape(L, NL, []),
 202 %    dot_unescape(Rest, NL2, [L2|Acc]);
 203 %dot_unescape([C|Rest], _, Acc) ->
 204 %    dot_unescape(Rest, false, [C|Acc]).
 205
 206
 207 %%
 208
 209 str2b64_final(String) ->
 210     str2b64_final(String, []).
 211
 212
 213 str2b64_final([], Acc) ->
 214     lists:reverse(Acc);
 215 str2b64_final(String, Acc) ->
 216     case str2b64_line(String, []) of
 217         {ok, Line, Rest} ->
 218             str2b64_final(Rest, ["\n",Line|Acc]);
 219         {more, Cont} ->
 220             lists:reverse(["\n",str2b64_end(Cont)|Acc])
 221     end.
 222
 223 %%
 224
 225 str2b64_line(S, []) -> str2b64_line(S, [], 0);
 226 str2b64_line(S, {Rest,Acc,N}) -> str2b64_line(Rest ++ S, Acc, N).
 227
 228 str2b64_line(S, Out, 76) -> {ok,lists:reverse(Out),S};
 229 str2b64_line([C1,C2,C3|S], Out, N) ->
 230     O1 = e(C1 bsr 2),
 231     O2 = e(((C1 band 16#03) bsl 4) bor (C2 bsr 4)),
 232     O3 = e(((C2 band 16#0f) bsl 2) bor (C3 bsr 6)),
 233     O4 = e(C3 band 16#3f),
 234     str2b64_line(S, [O4,O3,O2,O1|Out], N+4);
 235 str2b64_line(S, Out, N) ->
 236     {more,{S,Out,N}}.
 237
 238 %%
 239
 240 str2b64_end({[C1,C2],Out,_N}) ->
 241     O1 = e(C1 bsr 2),
 242     O2 = e(((C1 band 16#03) bsl 4) bor (C2 bsr 4)),
 243     O3 = e((C2 band 16#0f) bsl 2),
 244     lists:reverse(Out, [O1,O2,O3,$=]);
 245 str2b64_end({[C1],Out,_N}) ->
 246     O1 = e(C1 bsr 2),
 247     O2 = e((C1 band 16#03) bsl 4),
 248     lists:reverse(Out, [O1,O2,$=,$=]);
 249 str2b64_end({[],Out,_N}) -> lists:reverse(Out);
 250 str2b64_end([]) -> [].
 251
 252 %%
 253
 254 e(X) when X >= 0, X < 26 -> X + $A;
 255 e(X) when X >= 26, X < 52 -> X + $a - 26;
 256 e(X) when X >= 52, X < 62 -> X + $0 - 52;
 257 e(62) -> $+;
 258 e(63) -> $/;
 259 e(X) -> erlang:error({badchar,X}).
 260
 261
 262 %%
 263
 264
 265 weekday(Y,Mo,D) ->
 266     int_to_wd(calendar:day_of_the_week(Y,Mo,D)).
 267
 268 int_to_wd(1) -> "Mon";
 269 int_to_wd(2) -> "Tue";
 270 int_to_wd(3) -> "Wed";
 271 int_to_wd(4) -> "Thu";
 272 int_to_wd(5) -> "Fri";
 273 int_to_wd(6) -> "Sat";
 274 int_to_wd(7) -> "Sun".
 275
 276 int_to_mt(1)  -> "Jan";
 277 int_to_mt(2)  -> "Feb";
 278 int_to_mt(3)  -> "Mar";
 279 int_to_mt(4)  -> "Apr";
 280 int_to_mt(5)  -> "May";
 281 int_to_mt(6)  -> "Jun";
 282 int_to_mt(7)  -> "Jul";
 283 int_to_mt(8)  -> "Aug";
 284 int_to_mt(9)  -> "Sep";
 285 int_to_mt(10) -> "Oct";
 286 int_to_mt(11) -> "Nov";
 287 int_to_mt(12) -> "Dec".
 288
 289 %%
 290
 291 mail_header(_Key, []) -> [];
 292 mail_header(Key, Val) -> Key++Val++"\r\n".
 293
 294 %%
 295
 296 to_int(Str) ->
 297     to_int(Str, 0).
 298
 299 to_int([D|Ds], Acc) when D >= $0, D =< $9->
 300     to_int(Ds, Acc*10+D-$0);
 301 to_int(_, Acc) -> Acc.
 302
 303 %%
 304