2 * Copyright notice from original mutt:
3 * Copyright (C) 2000-5 Brendan Cully <brendan@kublai.com>
5 * This file is part of mutt-ng, see http://www.muttng.org/.
6 * It's licensed under the GNU General Public License,
7 * please see the file GPL in the top level source directory.
10 /* common SASL helper routines */
18 #include "mutt_sasl.h"
19 #include "mutt_socket.h"
22 #include "lib/debug.h"
26 #include <sasl/sasl.h>
28 #include <sys/socket.h>
29 #include <netinet/in.h>
31 static int getnameinfo_err (int ret)
37 debug_print (1, ("The name could not be resolved at this time. Future attempts may succeed.\n"));
41 debug_print (1, ("The flags had an invalid value.\n"));
45 debug_print (1, ("A non-recoverable error occurred.\n"));
49 debug_print (1, ("The address family was not recognized or the address length was invalid for the specified family.\n"));
53 debug_print (1, ("There was a memory allocation failure.\n"));
57 debug_print (1, ("The name does not resolve for the supplied parameters. NI_NAMEREQD is set and the host's name cannot be located, or both nodename and servname were null.\n"));
58 err = SASL_FAIL; /* no real equivalent */
61 debug_print (1, ("A system error occurred. The error code can be found in errno(%d,%s)).\n",
62 errno, strerror (errno)));
63 err = SASL_FAIL; /* no real equivalent */
66 debug_print (1, ("Unknown error %d\n", ret));
67 err = SASL_FAIL; /* no real equivalent */
73 /* arbitrary. SASL will probably use a smaller buffer anyway. OTOH it's
74 * been a while since I've had access to an SASL server which negotiated
75 * a protection buffer. */
76 #define M_SASL_MAXBUF 65536
78 #define IP_PORT_BUFLEN 1024
80 static sasl_callback_t mutt_sasl_callbacks[5];
82 static int mutt_sasl_start (void);
85 static int mutt_sasl_cb_log (void *context, int priority,
87 static int mutt_sasl_cb_authname (void *context, int id, const char **result,
89 static int mutt_sasl_cb_pass (sasl_conn_t * conn, void *context, int id,
90 sasl_secret_t ** psecret);
92 /* socket wrappers for a SASL security layer */
93 static int mutt_sasl_conn_open (CONNECTION * conn);
94 static int mutt_sasl_conn_close (CONNECTION * conn);
95 static int mutt_sasl_conn_read (CONNECTION * conn, char *buf, size_t len);
96 static int mutt_sasl_conn_write (CONNECTION * conn, const char *buf,
99 /* utility function, stolen from sasl2 sample code */
100 static int iptostring (const struct sockaddr *addr, socklen_t addrlen,
101 char *out, unsigned outlen)
103 char hbuf[NI_MAXHOST], pbuf[NI_MAXSERV];
107 return SASL_BADPARAM;
109 ret = getnameinfo (addr, addrlen, hbuf, sizeof (hbuf), pbuf, sizeof (pbuf),
111 #ifdef NI_WITHSCOPEID
116 return getnameinfo_err (ret);
118 if (outlen < str_len (hbuf) + str_len (pbuf) + 2)
121 snprintf (out, outlen, "%s;%s", hbuf, pbuf);
126 /* mutt_sasl_start: called before doing a SASL exchange - initialises library
128 int mutt_sasl_start (void)
130 static unsigned char sasl_init = 0;
132 static sasl_callback_t callbacks[2];
138 /* set up default logging callback */
139 callbacks[0].id = SASL_CB_LOG;
140 callbacks[0].proc = mutt_sasl_cb_log;
141 callbacks[0].context = NULL;
143 callbacks[1].id = SASL_CB_LIST_END;
144 callbacks[1].proc = NULL;
145 callbacks[1].context = NULL;
147 rc = sasl_client_init (callbacks);
150 debug_print (1, ("libsasl initialisation failed.\n"));
159 /* mutt_sasl_client_new: wrapper for sasl_client_new which also sets various
160 * security properties. If this turns out to be fine for POP too we can
161 * probably stop exporting mutt_sasl_get_callbacks(). */
162 int mutt_sasl_client_new (CONNECTION * conn, sasl_conn_t ** saslconn)
164 sasl_security_properties_t secprops;
166 struct sockaddr_storage local, remote;
168 char iplocalport[IP_PORT_BUFLEN], ipremoteport[IP_PORT_BUFLEN];
172 if (mutt_sasl_start () != SASL_OK)
175 switch (conn->account.type) {
176 case M_ACCT_TYPE_IMAP:
179 case M_ACCT_TYPE_POP:
183 debug_print (1, ("account type unset\n"));
187 size = sizeof (local);
188 if (getsockname (conn->fd, (struct sockaddr *) &local, &size)) {
189 debug_print (1, ("getsockname for local failed\n"));
194 ((struct sockaddr *) &local, size, iplocalport,
195 IP_PORT_BUFLEN) != SASL_OK) {
196 debug_print (1, ("iptostring for local failed\n"));
200 size = sizeof (remote);
201 if (getpeername (conn->fd, (struct sockaddr *) &remote, &size)) {
202 debug_print (1, ("getsockname for remote failed\n"));
207 ((struct sockaddr *) &remote, size, ipremoteport,
208 IP_PORT_BUFLEN) != SASL_OK) {
209 debug_print (1, ("iptostring for remote failed\n"));
213 debug_print (1, ("local ip: %s, remote ip:%s\n", iplocalport, ipremoteport));
216 sasl_client_new (service, conn->account.host, iplocalport, ipremoteport,
217 mutt_sasl_get_callbacks (&conn->account), 0, saslconn);
220 debug_print (1, ("Error allocating SASL connection\n"));
224 /*** set sasl IP properties, necessary for use with krb4 ***/
225 /* Do we need to fail if this fails? I would assume having these unset
226 * would just disable KRB4. Who wrote this code?
229 struct sockaddr_in local, remote;
232 size = sizeof (local);
233 if (getsockname (conn->fd, (struct sockaddr *) &local, &size))
236 size = sizeof (remote);
237 if (getpeername (conn->fd, (struct sockaddr *) &remote, &size))
241 if (sasl_setprop (*saslconn, SASL_IP_LOCAL, &local) != SASL_OK) {
242 debug_print (1, ("Error setting local IP address\n"));
247 #ifdef SASL_IP_REMOTE
248 if (sasl_setprop (*saslconn, SASL_IP_REMOTE, &remote) != SASL_OK) {
249 debug_print (1, ("Error setting remote IP address\n"));
255 /* set security properties. We use NOPLAINTEXT globally, since we can
256 * just fall back to LOGIN in the IMAP case anyway. If that doesn't
257 * work for POP, we can make it a flag or move this code into
258 * imap/auth_sasl.c */
259 memset (&secprops, 0, sizeof (secprops));
260 /* Work around a casting bug in the SASL krb4 module */
261 secprops.max_ssf = 0x7fff;
262 secprops.maxbufsize = M_SASL_MAXBUF;
263 secprops.security_flags |= SASL_SEC_NOPLAINTEXT;
264 if (sasl_setprop (*saslconn, SASL_SEC_PROPS, &secprops) != SASL_OK) {
265 debug_print (1, ("Error setting security properties\n"));
270 debug_print (2, ("External SSF: %d\n", conn->ssf));
271 if (sasl_setprop (*saslconn, SASL_SSF_EXTERNAL, &(conn->ssf)) != SASL_OK)
273 debug_print (1, ("Error setting external properties\n"));
276 debug_print (2, ("External authentication name: %s\n", conn->account.user));
277 if (sasl_setprop (*saslconn, SASL_AUTH_EXTERNAL, conn->account.user) !=
279 debug_print (1, ("Error setting external properties\n"));
287 sasl_callback_t *mutt_sasl_get_callbacks (ACCOUNT * account)
289 sasl_callback_t *callback;
291 callback = mutt_sasl_callbacks;
293 callback->id = SASL_CB_USER;
294 callback->proc = mutt_sasl_cb_authname;
295 callback->context = account;
298 callback->id = SASL_CB_AUTHNAME;
299 callback->proc = mutt_sasl_cb_authname;
300 callback->context = account;
303 callback->id = SASL_CB_PASS;
304 callback->proc = mutt_sasl_cb_pass;
305 callback->context = account;
308 callback->id = SASL_CB_GETREALM;
309 callback->proc = NULL;
310 callback->context = NULL;
313 callback->id = SASL_CB_LIST_END;
314 callback->proc = NULL;
315 callback->context = NULL;
317 return mutt_sasl_callbacks;
320 int mutt_sasl_interact (sasl_interact_t * interaction)
322 char prompt[SHORT_STRING];
323 char resp[SHORT_STRING];
325 while (interaction->id != SASL_CB_LIST_END) {
326 debug_print (2, ("filling in SASL interaction %ld.\n", interaction->id));
328 snprintf (prompt, sizeof (prompt), "%s: ", interaction->prompt);
330 if (mutt_get_field (prompt, resp, sizeof (resp), 0))
333 interaction->len = str_len (resp) + 1;
334 interaction->result = mem_malloc (interaction->len);
335 memcpy ((char*) interaction->result, resp, interaction->len);
343 /* SASL can stack a protection layer on top of an existing connection.
344 * To handle this, we store a saslconn_t in conn->sockdata, and write
345 * wrappers which en/decode the read/write stream, then replace sockdata
346 * with an embedded copy of the old sockdata and call the underlying
347 * functions (which we've also preserved). I thought about trying to make
348 * a general stackable connection system, but it seemed like overkill -
349 * something is wrong if we have 15 filters on top of a socket. Anyway,
350 * anything else which wishes to stack can use the same method. The only
351 * disadvantage is we have to write wrappers for all the socket methods,
352 * even if we only stack over read and write. Thinking about it, the
353 * abstraction problem is that there is more in CONNECTION than there
354 * needs to be. Ideally it would have only (void*)data and methods. */
356 /* mutt_sasl_setup_conn: replace connection methods, sockdata with
357 * SASL wrappers, for protection layers. Also get ssf, as a fastpath
358 * for the read/write methods. */
359 void mutt_sasl_setup_conn (CONNECTION * conn, sasl_conn_t * saslconn)
361 SASL_DATA *sasldata = (SASL_DATA *) mem_malloc (sizeof (SASL_DATA));
363 sasldata->saslconn = saslconn;
364 /* get ssf so we know whether we have to (en|de)code read/write */
365 sasl_getprop (saslconn, SASL_SSF, (const void **) &sasldata->ssf);
366 debug_print (3, ("SASL protection strength: %u\n", *sasldata->ssf));
367 /* Add SASL SSF to transport SSF */
368 conn->ssf += *sasldata->ssf;
369 sasl_getprop (saslconn, SASL_MAXOUTBUF,
370 (const void **) &sasldata->pbufsize);
371 debug_print (3, ("SASL protection buffer size: %u\n", *sasldata->pbufsize));
373 /* clear input buffer */
374 sasldata->buf = NULL;
378 /* preserve old functions */
379 sasldata->sockdata = conn->sockdata;
380 sasldata->msasl_open = conn->conn_open;
381 sasldata->msasl_close = conn->conn_close;
382 sasldata->msasl_read = conn->conn_read;
383 sasldata->msasl_write = conn->conn_write;
385 /* and set up new functions */
386 conn->sockdata = sasldata;
387 conn->conn_open = mutt_sasl_conn_open;
388 conn->conn_close = mutt_sasl_conn_close;
389 conn->conn_read = mutt_sasl_conn_read;
390 conn->conn_write = mutt_sasl_conn_write;
393 void mutt_sasl_done (void) {
397 /* mutt_sasl_cb_log: callback to log SASL messages */
398 static int mutt_sasl_cb_log (void *context, int priority, const char *message)
400 debug_print (priority, ("SASL: %s\n", message));
405 /* mutt_sasl_cb_authname: callback to retrieve authname or user from ACCOUNT */
406 static int mutt_sasl_cb_authname (void *context, int id, const char **result,
409 ACCOUNT *account = (ACCOUNT *) context;
416 return SASL_BADPARAM;
418 debug_print (2, ("getting %s for %s:%u\n",
419 id == SASL_CB_AUTHNAME ? "authname" : "user",
420 account->host, account->port));
422 if (id == SASL_CB_AUTHNAME) {
423 if (mutt_account_getlogin (account))
425 *result = account->login;
427 if (mutt_account_getuser (account))
429 *result = account->user;
433 *len = str_len (*result);
438 static int mutt_sasl_cb_pass (sasl_conn_t * conn, void *context, int id,
439 sasl_secret_t ** psecret)
441 ACCOUNT *account = (ACCOUNT *) context;
444 if (!account || !psecret)
445 return SASL_BADPARAM;
447 debug_print (2, ("getting password for %s@%s:%u\n",
448 account->login, account->host, account->port));
450 if (mutt_account_getpass (account))
453 len = str_len (account->pass);
455 *psecret = (sasl_secret_t *) mem_malloc (sizeof (sasl_secret_t) + len);
456 (*psecret)->len = len;
457 strcpy ((char*) (*psecret)->data, account->pass); /* __STRCPY_CHECKED__ */
462 /* mutt_sasl_conn_open: empty wrapper for underlying open function. We
463 * don't know in advance that a connection will use SASL, so we
464 * replace conn's methods with sasl methods when authentication
465 * is successful, using mutt_sasl_setup_conn */
466 static int mutt_sasl_conn_open (CONNECTION * conn)
471 sasldata = (SASL_DATA *) conn->sockdata;
472 conn->sockdata = sasldata->sockdata;
473 rc = (sasldata->msasl_open) (conn);
474 conn->sockdata = sasldata;
479 /* mutt_sasl_conn_close: calls underlying close function and disposes of
480 * the sasl_conn_t object, then restores connection to pre-sasl state */
481 static int mutt_sasl_conn_close (CONNECTION * conn)
486 sasldata = (SASL_DATA *) conn->sockdata;
488 /* restore connection's underlying methods */
489 conn->sockdata = sasldata->sockdata;
490 conn->conn_open = sasldata->msasl_open;
491 conn->conn_close = sasldata->msasl_close;
492 conn->conn_read = sasldata->msasl_read;
493 conn->conn_write = sasldata->msasl_write;
495 /* release sasl resources */
496 sasl_dispose (&sasldata->saslconn);
497 mem_free (&sasldata->buf);
498 mem_free (&sasldata);
500 /* call underlying close */
501 rc = (conn->conn_close) (conn);
506 static int mutt_sasl_conn_read (CONNECTION * conn, char *buf, size_t len)
513 sasldata = (SASL_DATA *) conn->sockdata;
515 /* if we still have data in our read buffer, copy it into buf */
516 if (sasldata->blen > sasldata->bpos) {
517 olen = (sasldata->blen - sasldata->bpos > len) ? len :
518 sasldata->blen - sasldata->bpos;
520 memcpy (buf, sasldata->buf + sasldata->bpos, olen);
521 sasldata->bpos += olen;
526 conn->sockdata = sasldata->sockdata;
528 mem_free (&sasldata->buf);
532 /* and decode the result, if necessary */
533 if (*sasldata->ssf) {
535 /* call the underlying read function to fill the buffer */
536 rc = (sasldata->msasl_read) (conn, buf, len);
540 rc = sasl_decode (sasldata->saslconn, buf, rc, &sasldata->buf,
543 debug_print (1, ("SASL decode failed: %s\n",
544 sasl_errstring (rc, NULL, NULL)));
548 while (!sasldata->blen);
550 olen = (sasldata->blen - sasldata->bpos > len) ? len :
551 sasldata->blen - sasldata->bpos;
553 memcpy (buf, sasldata->buf, olen);
554 sasldata->bpos += olen;
559 rc = (sasldata->msasl_read) (conn, buf, len);
562 conn->sockdata = sasldata;
567 static int mutt_sasl_conn_write (CONNECTION * conn, const char *buf,
574 unsigned int olen, plen;
576 sasldata = (SASL_DATA *) conn->sockdata;
577 conn->sockdata = sasldata->sockdata;
579 /* encode data, if necessary */
580 if (*sasldata->ssf) {
581 /* handle data larger than MAXOUTBUF */
583 olen = (len > *sasldata->pbufsize) ? *sasldata->pbufsize : len;
585 rc = sasl_encode (sasldata->saslconn, buf, olen, &pbuf, &plen);
587 debug_print (1, ("SASL encoding failed: %s\n",
588 sasl_errstring (rc, NULL, NULL)));
592 rc = (sasldata->msasl_write) (conn, pbuf, plen);
600 while (len > *sasldata->pbufsize);
603 /* just write using the underlying socket function */
604 rc = (sasldata->msasl_write) (conn, buf, len);
606 conn->sockdata = sasldata;
611 conn->sockdata = sasldata;