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 <sasl/sasl.h>
19 #include <sys/socket.h>
20 #include <netinet/in.h>
22 #include <lib-lib/mem.h>
23 #include <lib-lib/debug.h>
27 #include "mutt_sasl.h"
28 #include <lib-sys/mutt_socket.h>
30 static int getnameinfo_err (int ret)
36 debug_print (1, ("The name could not be resolved at this time. Future attempts may succeed.\n"));
40 debug_print (1, ("The flags had an invalid value.\n"));
44 debug_print (1, ("A non-recoverable error occurred.\n"));
48 debug_print (1, ("The address family was not recognized or the address length was invalid for the specified family.\n"));
52 debug_print (1, ("There was a memory allocation failure.\n"));
56 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"));
57 err = SASL_FAIL; /* no real equivalent */
60 debug_print (1, ("A system error occurred. The error code can be found in errno(%d,%s)).\n",
61 errno, strerror (errno)));
62 err = SASL_FAIL; /* no real equivalent */
65 debug_print (1, ("Unknown error %d\n", ret));
66 err = SASL_FAIL; /* no real equivalent */
72 /* arbitrary. SASL will probably use a smaller buffer anyway. OTOH it's
73 * been a while since I've had access to an SASL server which negotiated
74 * a protection buffer. */
75 #define M_SASL_MAXBUF 65536
77 #define IP_PORT_BUFLEN 1024
79 static sasl_callback_t mutt_sasl_callbacks[5];
81 static int mutt_sasl_start (void);
84 static int mutt_sasl_cb_log (void *context, int priority,
86 static int mutt_sasl_cb_authname (void *context, int id, const char **result,
88 static int mutt_sasl_cb_pass (sasl_conn_t * conn, void *context, int id,
89 sasl_secret_t ** psecret);
91 /* socket wrappers for a SASL security layer */
92 static int mutt_sasl_conn_open (CONNECTION * conn);
93 static int mutt_sasl_conn_close (CONNECTION * conn);
94 static int mutt_sasl_conn_read (CONNECTION * conn, char *buf, size_t len);
95 static int mutt_sasl_conn_write (CONNECTION * conn, const char *buf,
98 /* utility function, stolen from sasl2 sample code */
99 static int iptostring (const struct sockaddr *addr, socklen_t addrlen,
100 char *out, unsigned outlen)
102 char hbuf[NI_MAXHOST], pbuf[NI_MAXSERV];
106 return SASL_BADPARAM;
108 ret = getnameinfo (addr, addrlen, hbuf, sizeof (hbuf), pbuf, sizeof (pbuf),
110 #ifdef NI_WITHSCOPEID
115 return getnameinfo_err (ret);
117 if (outlen < m_strlen(hbuf) + m_strlen(pbuf) + 2)
120 snprintf (out, outlen, "%s;%s", hbuf, pbuf);
125 /* mutt_sasl_start: called before doing a SASL exchange - initialises library
127 int mutt_sasl_start (void)
129 static unsigned char sasl_init = 0;
131 static sasl_callback_t callbacks[2];
137 /* set up default logging callback */
138 callbacks[0].id = SASL_CB_LOG;
139 callbacks[0].proc = mutt_sasl_cb_log;
140 callbacks[0].context = NULL;
142 callbacks[1].id = SASL_CB_LIST_END;
143 callbacks[1].proc = NULL;
144 callbacks[1].context = NULL;
146 rc = sasl_client_init (callbacks);
149 debug_print (1, ("libsasl initialisation failed.\n"));
158 /* mutt_sasl_client_new: wrapper for sasl_client_new which also sets various
159 * security properties. If this turns out to be fine for POP too we can
160 * probably stop exporting mutt_sasl_get_callbacks(). */
161 int mutt_sasl_client_new (CONNECTION * conn, sasl_conn_t ** saslconn)
163 sasl_security_properties_t secprops;
165 struct sockaddr_storage local, remote;
167 char iplocalport[IP_PORT_BUFLEN], ipremoteport[IP_PORT_BUFLEN];
171 if (mutt_sasl_start () != SASL_OK)
174 switch (conn->account.type) {
175 case M_ACCT_TYPE_IMAP:
178 case M_ACCT_TYPE_POP:
182 debug_print (1, ("account type unset\n"));
186 size = sizeof (local);
187 if (getsockname (conn->fd, (struct sockaddr *) &local, &size)) {
188 debug_print (1, ("getsockname for local failed\n"));
193 ((struct sockaddr *) &local, size, iplocalport,
194 IP_PORT_BUFLEN) != SASL_OK) {
195 debug_print (1, ("iptostring for local failed\n"));
199 size = sizeof (remote);
200 if (getpeername (conn->fd, (struct sockaddr *) &remote, &size)) {
201 debug_print (1, ("getsockname for remote failed\n"));
206 ((struct sockaddr *) &remote, size, ipremoteport,
207 IP_PORT_BUFLEN) != SASL_OK) {
208 debug_print (1, ("iptostring for remote failed\n"));
212 debug_print (1, ("local ip: %s, remote ip:%s\n", iplocalport, ipremoteport));
215 sasl_client_new (service, conn->account.host, iplocalport, ipremoteport,
216 mutt_sasl_get_callbacks (&conn->account), 0, saslconn);
219 debug_print (1, ("Error allocating SASL connection\n"));
223 /*** set sasl IP properties, necessary for use with krb4 ***/
224 /* Do we need to fail if this fails? I would assume having these unset
225 * would just disable KRB4. Who wrote this code?
228 struct sockaddr_in local, remote;
231 size = sizeof (local);
232 if (getsockname (conn->fd, (struct sockaddr *) &local, &size))
235 size = sizeof (remote);
236 if (getpeername (conn->fd, (struct sockaddr *) &remote, &size))
240 if (sasl_setprop (*saslconn, SASL_IP_LOCAL, &local) != SASL_OK) {
241 debug_print (1, ("Error setting local IP address\n"));
246 #ifdef SASL_IP_REMOTE
247 if (sasl_setprop (*saslconn, SASL_IP_REMOTE, &remote) != SASL_OK) {
248 debug_print (1, ("Error setting remote IP address\n"));
254 /* set security properties. We use NOPLAINTEXT globally, since we can
255 * just fall back to LOGIN in the IMAP case anyway. If that doesn't
256 * work for POP, we can make it a flag or move this code into
257 * imap/auth_sasl.c */
258 p_clear(&secprops, 1);
259 /* Work around a casting bug in the SASL krb4 module */
260 secprops.max_ssf = 0x7fff;
261 secprops.maxbufsize = M_SASL_MAXBUF;
262 secprops.security_flags |= SASL_SEC_NOPLAINTEXT;
263 if (sasl_setprop (*saslconn, SASL_SEC_PROPS, &secprops) != SASL_OK) {
264 debug_print (1, ("Error setting security properties\n"));
269 debug_print (2, ("External SSF: %d\n", conn->ssf));
270 if (sasl_setprop (*saslconn, SASL_SSF_EXTERNAL, &(conn->ssf)) != SASL_OK)
272 debug_print (1, ("Error setting external properties\n"));
275 debug_print (2, ("External authentication name: %s\n", conn->account.user));
276 if (sasl_setprop (*saslconn, SASL_AUTH_EXTERNAL, conn->account.user) !=
278 debug_print (1, ("Error setting external properties\n"));
286 sasl_callback_t *mutt_sasl_get_callbacks (ACCOUNT * account)
288 sasl_callback_t *callback;
290 callback = mutt_sasl_callbacks;
292 callback->id = SASL_CB_USER;
293 callback->proc = mutt_sasl_cb_authname;
294 callback->context = account;
297 callback->id = SASL_CB_AUTHNAME;
298 callback->proc = mutt_sasl_cb_authname;
299 callback->context = account;
302 callback->id = SASL_CB_PASS;
303 callback->proc = mutt_sasl_cb_pass;
304 callback->context = account;
307 callback->id = SASL_CB_GETREALM;
308 callback->proc = NULL;
309 callback->context = NULL;
312 callback->id = SASL_CB_LIST_END;
313 callback->proc = NULL;
314 callback->context = NULL;
316 return mutt_sasl_callbacks;
319 int mutt_sasl_interact (sasl_interact_t * interaction)
321 char prompt[SHORT_STRING];
322 char resp[SHORT_STRING];
324 while (interaction->id != SASL_CB_LIST_END) {
325 debug_print (2, ("filling in SASL interaction %ld.\n", interaction->id));
327 snprintf (prompt, sizeof (prompt), "%s: ", interaction->prompt);
329 if (mutt_get_field (prompt, resp, sizeof (resp), 0))
332 interaction->len = m_strlen(resp) + 1;
333 interaction->result = p_dupstr(resp, interaction->len - 1);
340 /* SASL can stack a protection layer on top of an existing connection.
341 * To handle this, we store a saslconn_t in conn->sockdata, and write
342 * wrappers which en/decode the read/write stream, then replace sockdata
343 * with an embedded copy of the old sockdata and call the underlying
344 * functions (which we've also preserved). I thought about trying to make
345 * a general stackable connection system, but it seemed like overkill -
346 * something is wrong if we have 15 filters on top of a socket. Anyway,
347 * anything else which wishes to stack can use the same method. The only
348 * disadvantage is we have to write wrappers for all the socket methods,
349 * even if we only stack over read and write. Thinking about it, the
350 * abstraction problem is that there is more in CONNECTION than there
351 * needs to be. Ideally it would have only (void*)data and methods. */
353 /* mutt_sasl_setup_conn: replace connection methods, sockdata with
354 * SASL wrappers, for protection layers. Also get ssf, as a fastpath
355 * for the read/write methods. */
356 void mutt_sasl_setup_conn (CONNECTION * conn, sasl_conn_t * saslconn)
358 SASL_DATA *sasldata = p_new(SASL_DATA, 1);
360 sasldata->saslconn = saslconn;
361 /* get ssf so we know whether we have to (en|de)code read/write */
362 sasl_getprop (saslconn, SASL_SSF, (const void **)(void *)&sasldata->ssf);
363 debug_print (3, ("SASL protection strength: %u\n", *sasldata->ssf));
364 /* Add SASL SSF to transport SSF */
365 conn->ssf += *sasldata->ssf;
366 sasl_getprop (saslconn, SASL_MAXOUTBUF,
367 (const void **)(void *)&sasldata->pbufsize);
368 debug_print (3, ("SASL protection buffer size: %u\n", *sasldata->pbufsize));
370 /* clear input buffer */
371 sasldata->buf = NULL;
375 /* preserve old functions */
376 sasldata->sockdata = conn->sockdata;
377 sasldata->msasl_open = conn->conn_open;
378 sasldata->msasl_close = conn->conn_close;
379 sasldata->msasl_read = conn->conn_read;
380 sasldata->msasl_write = conn->conn_write;
382 /* and set up new functions */
383 conn->sockdata = sasldata;
384 conn->conn_open = mutt_sasl_conn_open;
385 conn->conn_close = mutt_sasl_conn_close;
386 conn->conn_read = mutt_sasl_conn_read;
387 conn->conn_write = mutt_sasl_conn_write;
390 void mutt_sasl_done (void) {
394 /* mutt_sasl_cb_log: callback to log SASL messages */
395 static int mutt_sasl_cb_log (void *context, int priority, const char *message)
397 debug_print (priority, ("SASL: %s\n", message));
402 /* mutt_sasl_cb_authname: callback to retrieve authname or user from ACCOUNT */
403 static int mutt_sasl_cb_authname (void *context, int id, const char **result,
406 ACCOUNT *account = (ACCOUNT *) context;
413 return SASL_BADPARAM;
415 debug_print (2, ("getting %s for %s:%u\n",
416 id == SASL_CB_AUTHNAME ? "authname" : "user",
417 account->host, account->port));
419 if (id == SASL_CB_AUTHNAME) {
420 if (mutt_account_getlogin (account))
422 *result = account->login;
424 if (mutt_account_getuser (account))
426 *result = account->user;
430 *len = m_strlen(*result);
435 static int mutt_sasl_cb_pass (sasl_conn_t * conn, void *context, int id,
436 sasl_secret_t ** psecret)
438 ACCOUNT *account = (ACCOUNT *) context;
441 if (!account || !psecret)
442 return SASL_BADPARAM;
444 debug_print (2, ("getting password for %s@%s:%u\n",
445 account->login, account->host, account->port));
447 if (mutt_account_getpass (account))
450 len = m_strlen(account->pass);
452 *psecret = xmalloc(sizeof(sasl_secret_t) + len);
453 (*psecret)->len = len;
454 strcpy ((char*) (*psecret)->data, account->pass); /* __STRCPY_CHECKED__ */
459 /* mutt_sasl_conn_open: empty wrapper for underlying open function. We
460 * don't know in advance that a connection will use SASL, so we
461 * replace conn's methods with sasl methods when authentication
462 * is successful, using mutt_sasl_setup_conn */
463 static int mutt_sasl_conn_open (CONNECTION * conn)
468 sasldata = (SASL_DATA *) conn->sockdata;
469 conn->sockdata = sasldata->sockdata;
470 rc = (sasldata->msasl_open) (conn);
471 conn->sockdata = sasldata;
476 /* mutt_sasl_conn_close: calls underlying close function and disposes of
477 * the sasl_conn_t object, then restores connection to pre-sasl state */
478 static int mutt_sasl_conn_close (CONNECTION * conn)
483 sasldata = (SASL_DATA *) conn->sockdata;
485 /* restore connection's underlying methods */
486 conn->sockdata = sasldata->sockdata;
487 conn->conn_open = sasldata->msasl_open;
488 conn->conn_close = sasldata->msasl_close;
489 conn->conn_read = sasldata->msasl_read;
490 conn->conn_write = sasldata->msasl_write;
492 /* release sasl resources */
493 sasl_dispose (&sasldata->saslconn);
494 p_delete(&sasldata->buf);
497 /* call underlying close */
498 rc = (conn->conn_close) (conn);
503 static int mutt_sasl_conn_read (CONNECTION * conn, char *buf, size_t len)
510 sasldata = (SASL_DATA *) conn->sockdata;
512 /* if we still have data in our read buffer, copy it into buf */
513 if (sasldata->blen > sasldata->bpos) {
514 olen = (sasldata->blen - sasldata->bpos > len) ? len :
515 sasldata->blen - sasldata->bpos;
517 memcpy (buf, sasldata->buf + sasldata->bpos, olen);
518 sasldata->bpos += olen;
523 conn->sockdata = sasldata->sockdata;
525 p_delete(&sasldata->buf);
529 /* and decode the result, if necessary */
530 if (*sasldata->ssf) {
532 /* call the underlying read function to fill the buffer */
533 rc = (sasldata->msasl_read) (conn, buf, len);
537 rc = sasl_decode (sasldata->saslconn, buf, rc, &sasldata->buf,
540 debug_print (1, ("SASL decode failed: %s\n",
541 sasl_errstring (rc, NULL, NULL)));
545 while (!sasldata->blen);
547 olen = (sasldata->blen - sasldata->bpos > len) ? len :
548 sasldata->blen - sasldata->bpos;
550 memcpy (buf, sasldata->buf, olen);
551 sasldata->bpos += olen;
556 rc = (sasldata->msasl_read) (conn, buf, len);
559 conn->sockdata = sasldata;
564 static int mutt_sasl_conn_write (CONNECTION * conn, const char *buf,
571 unsigned int olen, plen;
573 sasldata = (SASL_DATA *) conn->sockdata;
574 conn->sockdata = sasldata->sockdata;
576 /* encode data, if necessary */
577 if (*sasldata->ssf) {
578 /* handle data larger than MAXOUTBUF */
580 olen = (len > *sasldata->pbufsize) ? *sasldata->pbufsize : len;
582 rc = sasl_encode (sasldata->saslconn, buf, olen, &pbuf, &plen);
584 debug_print (1, ("SASL encoding failed: %s\n",
585 sasl_errstring (rc, NULL, NULL)));
589 rc = (sasldata->msasl_write) (conn, pbuf, plen);
597 while (len > *sasldata->pbufsize);
600 /* just write using the underlying socket function */
601 rc = (sasldata->msasl_write) (conn, buf, len);
603 conn->sockdata = sasldata;
608 conn->sockdata = sasldata;