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 */
74 /* arbitrary. SASL will probably use a smaller buffer anyway. OTOH it's
75 * been a while since I've had access to an SASL server which negotiated
76 * a protection buffer. */
77 #define M_SASL_MAXBUF 65536
79 #define IP_PORT_BUFLEN 1024
81 static sasl_callback_t mutt_sasl_callbacks[5];
83 static int mutt_sasl_start (void);
86 static int mutt_sasl_cb_log (void *context, int priority,
88 static int mutt_sasl_cb_authname (void *context, int id, const char **result,
90 static int mutt_sasl_cb_pass (sasl_conn_t * conn, void *context, int id,
91 sasl_secret_t ** psecret);
93 /* socket wrappers for a SASL security layer */
94 static int mutt_sasl_conn_open (CONNECTION * conn);
95 static int mutt_sasl_conn_close (CONNECTION * conn);
96 static int mutt_sasl_conn_read (CONNECTION * conn, char *buf, size_t len);
97 static int mutt_sasl_conn_write (CONNECTION * conn, const char *buf,
100 /* utility function, stolen from sasl2 sample code */
101 static int iptostring (const struct sockaddr *addr, socklen_t addrlen,
102 char *out, unsigned outlen)
104 char hbuf[NI_MAXHOST], pbuf[NI_MAXSERV];
108 return SASL_BADPARAM;
110 ret = getnameinfo (addr, addrlen, hbuf, sizeof (hbuf), pbuf, sizeof (pbuf),
112 #ifdef NI_WITHSCOPEID
117 return getnameinfo_err (ret);
119 if (outlen < str_len (hbuf) + str_len (pbuf) + 2)
122 snprintf (out, outlen, "%s;%s", hbuf, pbuf);
128 /* mutt_sasl_start: called before doing a SASL exchange - initialises library
130 int mutt_sasl_start (void)
132 static unsigned char sasl_init = 0;
134 static sasl_callback_t callbacks[2];
140 /* set up default logging callback */
141 callbacks[0].id = SASL_CB_LOG;
142 callbacks[0].proc = mutt_sasl_cb_log;
143 callbacks[0].context = NULL;
145 callbacks[1].id = SASL_CB_LIST_END;
146 callbacks[1].proc = NULL;
147 callbacks[1].context = NULL;
149 rc = sasl_client_init (callbacks);
152 debug_print (1, ("libsasl initialisation failed.\n"));
161 /* mutt_sasl_client_new: wrapper for sasl_client_new which also sets various
162 * security properties. If this turns out to be fine for POP too we can
163 * probably stop exporting mutt_sasl_get_callbacks(). */
164 int mutt_sasl_client_new (CONNECTION * conn, sasl_conn_t ** saslconn)
166 sasl_security_properties_t secprops;
168 struct sockaddr_storage local, remote;
170 char iplocalport[IP_PORT_BUFLEN], ipremoteport[IP_PORT_BUFLEN];
174 if (mutt_sasl_start () != SASL_OK)
177 switch (conn->account.type) {
178 case M_ACCT_TYPE_IMAP:
181 case M_ACCT_TYPE_POP:
185 debug_print (1, ("account type unset\n"));
189 size = sizeof (local);
190 if (getsockname (conn->fd, (struct sockaddr *) &local, &size)) {
191 debug_print (1, ("getsockname for local failed\n"));
196 ((struct sockaddr *) &local, size, iplocalport,
197 IP_PORT_BUFLEN) != SASL_OK) {
198 debug_print (1, ("iptostring for local failed\n"));
202 size = sizeof (remote);
203 if (getpeername (conn->fd, (struct sockaddr *) &remote, &size)) {
204 debug_print (1, ("getsockname for remote failed\n"));
209 ((struct sockaddr *) &remote, size, ipremoteport,
210 IP_PORT_BUFLEN) != SASL_OK) {
211 debug_print (1, ("iptostring for remote failed\n"));
215 debug_print (1, ("local ip: %s, remote ip:%s\n", iplocalport, ipremoteport));
218 sasl_client_new (service, conn->account.host, iplocalport, ipremoteport,
219 mutt_sasl_get_callbacks (&conn->account), 0, saslconn);
222 debug_print (1, ("Error allocating SASL connection\n"));
226 /*** set sasl IP properties, necessary for use with krb4 ***/
227 /* Do we need to fail if this fails? I would assume having these unset
228 * would just disable KRB4. Who wrote this code?
231 struct sockaddr_in local, remote;
234 size = sizeof (local);
235 if (getsockname (conn->fd, (struct sockaddr *) &local, &size))
238 size = sizeof (remote);
239 if (getpeername (conn->fd, (struct sockaddr *) &remote, &size))
243 if (sasl_setprop (*saslconn, SASL_IP_LOCAL, &local) != SASL_OK) {
244 debug_print (1, ("Error setting local IP address\n"));
249 #ifdef SASL_IP_REMOTE
250 if (sasl_setprop (*saslconn, SASL_IP_REMOTE, &remote) != SASL_OK) {
251 debug_print (1, ("Error setting remote IP address\n"));
257 /* set security properties. We use NOPLAINTEXT globally, since we can
258 * just fall back to LOGIN in the IMAP case anyway. If that doesn't
259 * work for POP, we can make it a flag or move this code into
260 * imap/auth_sasl.c */
261 memset (&secprops, 0, sizeof (secprops));
262 /* Work around a casting bug in the SASL krb4 module */
263 secprops.max_ssf = 0x7fff;
264 secprops.maxbufsize = M_SASL_MAXBUF;
265 secprops.security_flags |= SASL_SEC_NOPLAINTEXT;
266 if (sasl_setprop (*saslconn, SASL_SEC_PROPS, &secprops) != SASL_OK) {
267 debug_print (1, ("Error setting security properties\n"));
272 debug_print (2, ("External SSF: %d\n", conn->ssf));
273 if (sasl_setprop (*saslconn, SASL_SSF_EXTERNAL, &(conn->ssf)) != SASL_OK)
275 debug_print (1, ("Error setting external properties\n"));
278 debug_print (2, ("External authentication name: %s\n", conn->account.user));
279 if (sasl_setprop (*saslconn, SASL_AUTH_EXTERNAL, conn->account.user) !=
281 debug_print (1, ("Error setting external properties\n"));
289 sasl_callback_t *mutt_sasl_get_callbacks (ACCOUNT * account)
291 sasl_callback_t *callback;
293 callback = mutt_sasl_callbacks;
295 callback->id = SASL_CB_USER;
296 callback->proc = mutt_sasl_cb_authname;
297 callback->context = account;
300 callback->id = SASL_CB_AUTHNAME;
301 callback->proc = mutt_sasl_cb_authname;
302 callback->context = account;
305 callback->id = SASL_CB_PASS;
306 callback->proc = mutt_sasl_cb_pass;
307 callback->context = account;
310 callback->id = SASL_CB_GETREALM;
311 callback->proc = NULL;
312 callback->context = NULL;
315 callback->id = SASL_CB_LIST_END;
316 callback->proc = NULL;
317 callback->context = NULL;
319 return mutt_sasl_callbacks;
322 int mutt_sasl_interact (sasl_interact_t * interaction)
324 char prompt[SHORT_STRING];
325 char resp[SHORT_STRING];
327 while (interaction->id != SASL_CB_LIST_END) {
328 debug_print (2, ("filling in SASL interaction %ld.\n", interaction->id));
330 snprintf (prompt, sizeof (prompt), "%s: ", interaction->prompt);
332 if (mutt_get_field (prompt, resp, sizeof (resp), 0))
335 interaction->len = str_len (resp) + 1;
336 interaction->result = mem_malloc (interaction->len);
337 memcpy ((char*) interaction->result, resp, interaction->len);
345 /* SASL can stack a protection layer on top of an existing connection.
346 * To handle this, we store a saslconn_t in conn->sockdata, and write
347 * wrappers which en/decode the read/write stream, then replace sockdata
348 * with an embedded copy of the old sockdata and call the underlying
349 * functions (which we've also preserved). I thought about trying to make
350 * a general stackable connection system, but it seemed like overkill -
351 * something is wrong if we have 15 filters on top of a socket. Anyway,
352 * anything else which wishes to stack can use the same method. The only
353 * disadvantage is we have to write wrappers for all the socket methods,
354 * even if we only stack over read and write. Thinking about it, the
355 * abstraction problem is that there is more in CONNECTION than there
356 * needs to be. Ideally it would have only (void*)data and methods. */
358 /* mutt_sasl_setup_conn: replace connection methods, sockdata with
359 * SASL wrappers, for protection layers. Also get ssf, as a fastpath
360 * for the read/write methods. */
361 void mutt_sasl_setup_conn (CONNECTION * conn, sasl_conn_t * saslconn)
363 SASL_DATA *sasldata = (SASL_DATA *) mem_malloc (sizeof (SASL_DATA));
365 sasldata->saslconn = saslconn;
366 /* get ssf so we know whether we have to (en|de)code read/write */
367 sasl_getprop (saslconn, SASL_SSF, (const void **) &sasldata->ssf);
368 debug_print (3, ("SASL protection strength: %u\n", *sasldata->ssf));
369 /* Add SASL SSF to transport SSF */
370 conn->ssf += *sasldata->ssf;
371 sasl_getprop (saslconn, SASL_MAXOUTBUF,
372 (const void **) &sasldata->pbufsize);
373 debug_print (3, ("SASL protection buffer size: %u\n", *sasldata->pbufsize));
375 /* clear input buffer */
376 sasldata->buf = NULL;
380 /* preserve old functions */
381 sasldata->sockdata = conn->sockdata;
382 sasldata->msasl_open = conn->conn_open;
383 sasldata->msasl_close = conn->conn_close;
384 sasldata->msasl_read = conn->conn_read;
385 sasldata->msasl_write = conn->conn_write;
387 /* and set up new functions */
388 conn->sockdata = sasldata;
389 conn->conn_open = mutt_sasl_conn_open;
390 conn->conn_close = mutt_sasl_conn_close;
391 conn->conn_read = mutt_sasl_conn_read;
392 conn->conn_write = mutt_sasl_conn_write;
395 void mutt_sasl_done (void) {
399 /* mutt_sasl_cb_log: callback to log SASL messages */
400 static int mutt_sasl_cb_log (void *context, int priority, const char *message)
402 debug_print (priority, ("SASL: %s\n", message));
407 /* mutt_sasl_cb_authname: callback to retrieve authname or user from ACCOUNT */
408 static int mutt_sasl_cb_authname (void *context, int id, const char **result,
411 ACCOUNT *account = (ACCOUNT *) context;
418 return SASL_BADPARAM;
420 debug_print (2, ("getting %s for %s:%u\n",
421 id == SASL_CB_AUTHNAME ? "authname" : "user",
422 account->host, account->port));
424 if (id == SASL_CB_AUTHNAME) {
425 if (mutt_account_getlogin (account))
427 *result = account->login;
429 if (mutt_account_getuser (account))
431 *result = account->user;
435 *len = str_len (*result);
440 static int mutt_sasl_cb_pass (sasl_conn_t * conn, void *context, int id,
441 sasl_secret_t ** psecret)
443 ACCOUNT *account = (ACCOUNT *) context;
446 if (!account || !psecret)
447 return SASL_BADPARAM;
449 debug_print (2, ("getting password for %s@%s:%u\n",
450 account->login, account->host, account->port));
452 if (mutt_account_getpass (account))
455 len = str_len (account->pass);
457 *psecret = (sasl_secret_t *) mem_malloc (sizeof (sasl_secret_t) + len);
458 (*psecret)->len = len;
459 strcpy ((char*) (*psecret)->data, account->pass); /* __STRCPY_CHECKED__ */
464 /* mutt_sasl_conn_open: empty wrapper for underlying open function. We
465 * don't know in advance that a connection will use SASL, so we
466 * replace conn's methods with sasl methods when authentication
467 * is successful, using mutt_sasl_setup_conn */
468 static int mutt_sasl_conn_open (CONNECTION * conn)
473 sasldata = (SASL_DATA *) conn->sockdata;
474 conn->sockdata = sasldata->sockdata;
475 rc = (sasldata->msasl_open) (conn);
476 conn->sockdata = sasldata;
481 /* mutt_sasl_conn_close: calls underlying close function and disposes of
482 * the sasl_conn_t object, then restores connection to pre-sasl state */
483 static int mutt_sasl_conn_close (CONNECTION * conn)
488 sasldata = (SASL_DATA *) conn->sockdata;
490 /* restore connection's underlying methods */
491 conn->sockdata = sasldata->sockdata;
492 conn->conn_open = sasldata->msasl_open;
493 conn->conn_close = sasldata->msasl_close;
494 conn->conn_read = sasldata->msasl_read;
495 conn->conn_write = sasldata->msasl_write;
497 /* release sasl resources */
498 sasl_dispose (&sasldata->saslconn);
499 mem_free (&sasldata->buf);
500 mem_free (&sasldata);
502 /* call underlying close */
503 rc = (conn->conn_close) (conn);
508 static int mutt_sasl_conn_read (CONNECTION * conn, char *buf, size_t len)
515 sasldata = (SASL_DATA *) conn->sockdata;
517 /* if we still have data in our read buffer, copy it into buf */
518 if (sasldata->blen > sasldata->bpos) {
519 olen = (sasldata->blen - sasldata->bpos > len) ? len :
520 sasldata->blen - sasldata->bpos;
522 memcpy (buf, sasldata->buf + sasldata->bpos, olen);
523 sasldata->bpos += olen;
528 conn->sockdata = sasldata->sockdata;
530 mem_free (&sasldata->buf);
534 /* and decode the result, if necessary */
535 if (*sasldata->ssf) {
537 /* call the underlying read function to fill the buffer */
538 rc = (sasldata->msasl_read) (conn, buf, len);
542 rc = sasl_decode (sasldata->saslconn, buf, rc, &sasldata->buf,
545 debug_print (1, ("SASL decode failed: %s\n",
546 sasl_errstring (rc, NULL, NULL)));
550 while (!sasldata->blen);
552 olen = (sasldata->blen - sasldata->bpos > len) ? len :
553 sasldata->blen - sasldata->bpos;
555 memcpy (buf, sasldata->buf, olen);
556 sasldata->bpos += olen;
561 rc = (sasldata->msasl_read) (conn, buf, len);
564 conn->sockdata = sasldata;
569 static int mutt_sasl_conn_write (CONNECTION * conn, const char *buf,
576 unsigned int olen, plen;
578 sasldata = (SASL_DATA *) conn->sockdata;
579 conn->sockdata = sasldata->sockdata;
581 /* encode data, if necessary */
582 if (*sasldata->ssf) {
583 /* handle data larger than MAXOUTBUF */
585 olen = (len > *sasldata->pbufsize) ? *sasldata->pbufsize : len;
587 rc = sasl_encode (sasldata->saslconn, buf, olen, &pbuf, &plen);
589 debug_print (1, ("SASL encoding failed: %s\n",
590 sasl_errstring (rc, NULL, NULL)));
594 rc = (sasldata->msasl_write) (conn, pbuf, plen);
602 while (len > *sasldata->pbufsize);
605 /* just write using the underlying socket function */
606 rc = (sasldata->msasl_write) (conn, buf, len);
608 conn->sockdata = sasldata;
613 conn->sockdata = sasldata;