1 /* $Cambridge: exim/src/src/auths/dovecot.c,v 1.12 2010/03/05 16:11:11 nm4 Exp $ */
4 * Copyright (c) 2004 Andrey Panin <pazke@donpac.ru>
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published
8 * by the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
12 /* A number of modifications have been made to the original code. Originally I
13 commented them specially, but now they are getting quite extensive, so I have
14 ceased doing that. The biggest change is to use unbuffered I/O on the socket
15 because using C buffered I/O gives problems on some operating systems. PH */
20 #define VERSION_MAJOR 1
21 #define VERSION_MINOR 0
23 /* Options specific to the authentication mechanism. */
24 optionlist auth_dovecot_options
[] = {
28 (void *)(offsetof(auth_dovecot_options_block
, server_socket
))
32 /* Size of the options list. An extern variable has to be used so that its
33 address can appear in the tables drtables.c. */
35 int auth_dovecot_options_count
=
36 sizeof(auth_dovecot_options
) / sizeof(optionlist
);
38 /* Default private options block for the authentication method. */
40 auth_dovecot_options_block auth_dovecot_option_defaults
= {
41 NULL
, /* server_socket */
45 /* Static variables for reading from the socket */
47 static uschar sbuffer
[256];
52 /*************************************************
53 * Initialization entry point *
54 *************************************************/
56 /* Called for each instance, after its options have been read, to
57 enable consistency checks to be done, or anything else that needs
60 void auth_dovecot_init(auth_instance
*ablock
)
62 auth_dovecot_options_block
*ob
=
63 (auth_dovecot_options_block
*)(ablock
->options_block
);
65 if (ablock
->public_name
== NULL
)
66 ablock
->public_name
= ablock
->name
;
67 if (ob
->server_socket
!= NULL
)
68 ablock
->server
= TRUE
;
69 ablock
->client
= FALSE
;
72 static int strcut(uschar
*str
, uschar
**ptrs
, int nptrs
)
77 for (n
= 0; n
< nptrs
; n
++)
99 #define CHECK_COMMAND(str, arg_min, arg_max) do { \
100 if (strcmpic(US(str), args[0]) != 0) \
102 if (nargs - 1 < (arg_min)) \
104 if ( (arg_max != -1) && (nargs - 1 > (arg_max)) ) \
108 #define OUT(msg) do { \
109 auth_defer_msg = (US msg); \
115 /*************************************************
116 * "fgets" to read directly from socket *
117 *************************************************/
119 /* Added by PH after a suggestion by Steve Usher because the previous use of
120 C-style buffered I/O gave trouble. */
123 dc_gets(uschar
*s
, int n
, int fd
)
132 sbp
= read(fd
, sbuffer
, sizeof(sbuffer
));
133 if (sbp
== 0) { if (count
== 0) return NULL
; else break; }
139 if (count
>= n
- 1) break;
140 s
[count
++] = sbuffer
[p
];
141 if (sbuffer
[p
++] == '\n') break;
144 memmove(sbuffer
, sbuffer
+ p
, sbp
- p
);
147 if (s
[count
-1] == '\n' || count
>= n
- 1) break;
157 /*************************************************
158 * Server entry point *
159 *************************************************/
161 int auth_dovecot_server(auth_instance
*ablock
, uschar
*data
)
163 auth_dovecot_options_block
*ob
=
164 (auth_dovecot_options_block
*)(ablock
->options_block
);
165 struct sockaddr_un sa
;
168 uschar
*auth_command
;
169 uschar
*auth_extra_data
= US
"";
171 int cuid
= 0, cont
= 1, found
= 0, fd
, ret
= DEFER
;
173 HDEBUG(D_auth
) debug_printf("dovecot authentication\n");
175 memset(&sa
, 0, sizeof(sa
));
176 sa
.sun_family
= AF_UNIX
;
178 /* This was the original code here: it is nonsense because strncpy()
179 does not return an integer. I have converted this to use the function
180 that formats and checks length. PH */
183 if (strncpy(sa.sun_path, ob->server_socket, sizeof(sa.sun_path)) < 0) {
186 if (!string_format(US sa
.sun_path
, sizeof(sa
.sun_path
), "%s",
187 ob
->server_socket
)) {
188 auth_defer_msg
= US
"authentication socket path too long";
192 auth_defer_msg
= US
"authentication socket connection error";
194 fd
= socket(PF_UNIX
, SOCK_STREAM
, 0);
198 if (connect(fd
, (struct sockaddr
*) &sa
, sizeof(sa
)) < 0)
201 auth_defer_msg
= US
"authentication socket protocol error";
203 sbp
= 0; /* Socket buffer pointer */
205 if (dc_gets(buffer
, sizeof(buffer
), fd
) == NULL
)
206 OUT("authentication socket read error or premature eof");
208 buffer
[Ustrlen(buffer
) - 1] = 0;
209 HDEBUG(D_auth
) debug_printf("received: %s\n", buffer
);
210 nargs
= strcut(buffer
, args
, sizeof(args
) / sizeof(args
[0]));
212 /* Code below rewritten by Kirill Miazine (km@krot.org). Only check commands that
213 Exim will need. Original code also failed if Dovecot server sent unknown
214 command. E.g. COOKIE in version 1.1 of the protocol would cause troubles. */
215 if (Ustrcmp(args
[0], US
"CUID") == 0) {
216 CHECK_COMMAND("CUID", 1, 1);
217 cuid
= Uatoi(args
[1]);
218 } else if (Ustrcmp(args
[0], US
"VERSION") == 0) {
219 CHECK_COMMAND("VERSION", 2, 2);
220 if (Uatoi(args
[1]) != VERSION_MAJOR
)
221 OUT("authentication socket protocol version mismatch");
222 } else if (Ustrcmp(args
[0], US
"MECH") == 0) {
223 CHECK_COMMAND("MECH", 1, INT_MAX
);
224 if (strcmpic(US args
[1], ablock
->public_name
) == 0)
226 } else if (Ustrcmp(args
[0], US
"DONE") == 0) {
227 CHECK_COMMAND("DONE", 0, 0);
235 /* Added by PH: data must not contain tab (as it is
236 b64 it shouldn't, but check for safety). */
238 if (Ustrchr(data
, '\t') != NULL
) {
243 /* Added by PH: extra fields when TLS is in use or if the TCP/IP
244 connection is local. */
246 if (tls_cipher
!= NULL
)
247 auth_extra_data
= string_sprintf("secured\t%s%s",
248 tls_certificate_verified
? "valid-client-cert" : "",
249 tls_certificate_verified
? "\t" : "");
250 else if (interface_address
!= NULL
&&
251 Ustrcmp(sender_host_address
, interface_address
) == 0)
252 auth_extra_data
= US
"secured\t";
255 /****************************************************************************
256 The code below was the original code here. It didn't work. A reading of the
257 file auth-protocol.txt.gz that came with Dovecot 1.0_beta8 indicated that
258 this was not right. Maybe something changed. I changed it to move the
259 service indication into the AUTH command, and it seems to be better. PH
261 fprintf(f, "VERSION\t%d\t%d\r\nSERVICE\tSMTP\r\nCPID\t%d\r\n"
262 "AUTH\t%d\t%s\trip=%s\tlip=%s\tresp=%s\r\n",
263 VERSION_MAJOR, VERSION_MINOR, getpid(), cuid,
264 ablock->public_name, sender_host_address, interface_address,
265 data ? (char *) data : "");
267 Subsequently, the command was modified to add "secured" and "valid-client-
270 The auth protocol is documented here:
271 http://wiki.dovecot.org/Authentication_Protocol
272 ****************************************************************************/
274 auth_command
= string_sprintf("VERSION\t%d\t%d\nCPID\t%d\n"
275 "AUTH\t%d\t%s\tservice=smtp\t%srip=%s\tlip=%s\tnologin\tresp=%s\n",
276 VERSION_MAJOR
, VERSION_MINOR
, getpid(), cuid
,
277 ablock
->public_name
, auth_extra_data
, sender_host_address
,
278 interface_address
, data
? (char *) data
: "");
280 if (write(fd
, auth_command
, Ustrlen(auth_command
)) < 0)
281 HDEBUG(D_auth
) debug_printf("error sending auth_command: %s\n",
284 HDEBUG(D_auth
) debug_printf("sent: %s", auth_command
);
288 uschar
*auth_id_pre
= NULL
;
291 if (dc_gets(buffer
, sizeof(buffer
), fd
) == NULL
) {
292 auth_defer_msg
= US
"authentication socket read error or premature eof";
296 buffer
[Ustrlen(buffer
) - 1] = 0;
297 HDEBUG(D_auth
) debug_printf("received: %s\n", buffer
);
298 nargs
= strcut(buffer
, args
, sizeof(args
) / sizeof(args
[0]));
300 if (Uatoi(args
[1]) != cuid
)
301 OUT("authentication socket connection id mismatch");
303 switch (toupper(*args
[0])) {
305 CHECK_COMMAND("CONT", 1, 2);
307 tmp
= auth_get_no64_data(&data
, US args
[2]);
313 /* Added by PH: data must not contain tab (as it is
314 b64 it shouldn't, but check for safety). */
316 if (Ustrchr(data
, '\t') != NULL
) {
321 temp
= string_sprintf("CONT\t%d\t%s\n", cuid
, data
);
322 if (write(fd
, temp
, Ustrlen(temp
)) < 0)
323 OUT("authentication socket write error");
327 CHECK_COMMAND("FAIL", 1, -1);
329 for (i
=2; (i
<nargs
) && (auth_id_pre
== NULL
); i
++)
331 if ( Ustrncmp(args
[i
], US
"user=", 5) == 0 )
333 auth_id_pre
= args
[i
]+5;
334 expand_nstring
[1] = auth_vars
[0] =
335 string_copy(auth_id_pre
); /* PH */
336 expand_nlength
[1] = Ustrlen(auth_id_pre
);
345 CHECK_COMMAND("OK", 2, -1);
348 * Search for the "user=$USER" string in the args array
349 * and return the proper value.
351 for (i
=2; (i
<nargs
) && (auth_id_pre
== NULL
); i
++)
353 if ( Ustrncmp(args
[i
], US
"user=", 5) == 0 )
355 auth_id_pre
= args
[i
]+5;
356 expand_nstring
[1] = auth_vars
[0] =
357 string_copy(auth_id_pre
); /* PH */
358 expand_nlength
[1] = Ustrlen(auth_id_pre
);
363 if (auth_id_pre
== NULL
)
364 OUT("authentication socket protocol error, username missing");
375 /* close the socket used by dovecot */
379 /* Expand server_condition as an authorization check */
380 return (ret
== OK
)? auth_check_serv_cond(ablock
) : ret
;