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 */
16 #include <lib-lib/mem.h>
20 #include "mutt_sasl.h"
21 #include "mutt_socket.h"
23 #include "lib/debug.h"
27 #include <sasl/sasl.h>
29 #include <sys/socket.h>
30 #include <netinet/in.h>
32 static int getnameinfo_err (int ret)
38 debug_print (1, ("The name could not be resolved at this time. Future attempts may succeed.\n"));
42 debug_print (1, ("The flags had an invalid value.\n"));
46 debug_print (1, ("A non-recoverable error occurred.\n"));
50 debug_print (1, ("The address family was not recognized or the address length was invalid for the specified family.\n"));
54 debug_print (1, ("There was a memory allocation failure.\n"));
58 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"));
59 err = SASL_FAIL; /* no real equivalent */
62 debug_print (1, ("A system error occurred. The error code can be found in errno(%d,%s)).\n",
63 errno, strerror (errno)));
64 err = SASL_FAIL; /* no real equivalent */
67 debug_print (1, ("Unknown error %d\n", ret));
68 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 < m_strlen(hbuf) + m_strlen(pbuf) + 2)
122 snprintf (out, outlen, "%s;%s", hbuf, pbuf);
127 /* mutt_sasl_start: called before doing a SASL exchange - initialises library
129 int mutt_sasl_start (void)
131 static unsigned char sasl_init = 0;
133 static sasl_callback_t callbacks[2];
139 /* set up default logging callback */
140 callbacks[0].id = SASL_CB_LOG;
141 callbacks[0].proc = mutt_sasl_cb_log;
142 callbacks[0].context = NULL;
144 callbacks[1].id = SASL_CB_LIST_END;
145 callbacks[1].proc = NULL;
146 callbacks[1].context = NULL;
148 rc = sasl_client_init (callbacks);
151 debug_print (1, ("libsasl initialisation failed.\n"));
160 /* mutt_sasl_client_new: wrapper for sasl_client_new which also sets various
161 * security properties. If this turns out to be fine for POP too we can
162 * probably stop exporting mutt_sasl_get_callbacks(). */
163 int mutt_sasl_client_new (CONNECTION * conn, sasl_conn_t ** saslconn)
165 sasl_security_properties_t secprops;
167 struct sockaddr_storage local, remote;
169 char iplocalport[IP_PORT_BUFLEN], ipremoteport[IP_PORT_BUFLEN];
173 if (mutt_sasl_start () != SASL_OK)
176 switch (conn->account.type) {
177 case M_ACCT_TYPE_IMAP:
180 case M_ACCT_TYPE_POP:
184 debug_print (1, ("account type unset\n"));
188 size = sizeof (local);
189 if (getsockname (conn->fd, (struct sockaddr *) &local, &size)) {
190 debug_print (1, ("getsockname for local failed\n"));
195 ((struct sockaddr *) &local, size, iplocalport,
196 IP_PORT_BUFLEN) != SASL_OK) {
197 debug_print (1, ("iptostring for local failed\n"));
201 size = sizeof (remote);
202 if (getpeername (conn->fd, (struct sockaddr *) &remote, &size)) {
203 debug_print (1, ("getsockname for remote failed\n"));
208 ((struct sockaddr *) &remote, size, ipremoteport,
209 IP_PORT_BUFLEN) != SASL_OK) {
210 debug_print (1, ("iptostring for remote failed\n"));
214 debug_print (1, ("local ip: %s, remote ip:%s\n", iplocalport, ipremoteport));
217 sasl_client_new (service, conn->account.host, iplocalport, ipremoteport,
218 mutt_sasl_get_callbacks (&conn->account), 0, saslconn);
221 debug_print (1, ("Error allocating SASL connection\n"));
225 /*** set sasl IP properties, necessary for use with krb4 ***/
226 /* Do we need to fail if this fails? I would assume having these unset
227 * would just disable KRB4. Who wrote this code?
230 struct sockaddr_in local, remote;
233 size = sizeof (local);
234 if (getsockname (conn->fd, (struct sockaddr *) &local, &size))
237 size = sizeof (remote);
238 if (getpeername (conn->fd, (struct sockaddr *) &remote, &size))
242 if (sasl_setprop (*saslconn, SASL_IP_LOCAL, &local) != SASL_OK) {
243 debug_print (1, ("Error setting local IP address\n"));
248 #ifdef SASL_IP_REMOTE
249 if (sasl_setprop (*saslconn, SASL_IP_REMOTE, &remote) != SASL_OK) {
250 debug_print (1, ("Error setting remote IP address\n"));
256 /* set security properties. We use NOPLAINTEXT globally, since we can
257 * just fall back to LOGIN in the IMAP case anyway. If that doesn't
258 * work for POP, we can make it a flag or move this code into
259 * imap/auth_sasl.c */
260 p_clear(&secprops, 1);
261 /* Work around a casting bug in the SASL krb4 module */
262 secprops.max_ssf = 0x7fff;
263 secprops.maxbufsize = M_SASL_MAXBUF;
264 secprops.security_flags |= SASL_SEC_NOPLAINTEXT;
265 if (sasl_setprop (*saslconn, SASL_SEC_PROPS, &secprops) != SASL_OK) {
266 debug_print (1, ("Error setting security properties\n"));
271 debug_print (2, ("External SSF: %d\n", conn->ssf));
272 if (sasl_setprop (*saslconn, SASL_SSF_EXTERNAL, &(conn->ssf)) != SASL_OK)
274 debug_print (1, ("Error setting external properties\n"));
277 debug_print (2, ("External authentication name: %s\n", conn->account.user));
278 if (sasl_setprop (*saslconn, SASL_AUTH_EXTERNAL, conn->account.user) !=
280 debug_print (1, ("Error setting external properties\n"));
288 sasl_callback_t *mutt_sasl_get_callbacks (ACCOUNT * account)
290 sasl_callback_t *callback;
292 callback = mutt_sasl_callbacks;
294 callback->id = SASL_CB_USER;
295 callback->proc = mutt_sasl_cb_authname;
296 callback->context = account;
299 callback->id = SASL_CB_AUTHNAME;
300 callback->proc = mutt_sasl_cb_authname;
301 callback->context = account;
304 callback->id = SASL_CB_PASS;
305 callback->proc = mutt_sasl_cb_pass;
306 callback->context = account;
309 callback->id = SASL_CB_GETREALM;
310 callback->proc = NULL;
311 callback->context = NULL;
314 callback->id = SASL_CB_LIST_END;
315 callback->proc = NULL;
316 callback->context = NULL;
318 return mutt_sasl_callbacks;
321 int mutt_sasl_interact (sasl_interact_t * interaction)
323 char prompt[SHORT_STRING];
324 char resp[SHORT_STRING];
326 while (interaction->id != SASL_CB_LIST_END) {
327 debug_print (2, ("filling in SASL interaction %ld.\n", interaction->id));
329 snprintf (prompt, sizeof (prompt), "%s: ", interaction->prompt);
331 if (mutt_get_field (prompt, resp, sizeof (resp), 0))
334 interaction->len = m_strlen(resp) + 1;
335 interaction->result = p_dupstr(resp, interaction->len - 1);
342 /* SASL can stack a protection layer on top of an existing connection.
343 * To handle this, we store a saslconn_t in conn->sockdata, and write
344 * wrappers which en/decode the read/write stream, then replace sockdata
345 * with an embedded copy of the old sockdata and call the underlying
346 * functions (which we've also preserved). I thought about trying to make
347 * a general stackable connection system, but it seemed like overkill -
348 * something is wrong if we have 15 filters on top of a socket. Anyway,
349 * anything else which wishes to stack can use the same method. The only
350 * disadvantage is we have to write wrappers for all the socket methods,
351 * even if we only stack over read and write. Thinking about it, the
352 * abstraction problem is that there is more in CONNECTION than there
353 * needs to be. Ideally it would have only (void*)data and methods. */
355 /* mutt_sasl_setup_conn: replace connection methods, sockdata with
356 * SASL wrappers, for protection layers. Also get ssf, as a fastpath
357 * for the read/write methods. */
358 void mutt_sasl_setup_conn (CONNECTION * conn, sasl_conn_t * saslconn)
360 SASL_DATA *sasldata = p_new(SASL_DATA, 1);
362 sasldata->saslconn = saslconn;
363 /* get ssf so we know whether we have to (en|de)code read/write */
364 sasl_getprop (saslconn, SASL_SSF, (const void **)(void *)&sasldata->ssf);
365 debug_print (3, ("SASL protection strength: %u\n", *sasldata->ssf));
366 /* Add SASL SSF to transport SSF */
367 conn->ssf += *sasldata->ssf;
368 sasl_getprop (saslconn, SASL_MAXOUTBUF,
369 (const void **)(void *)&sasldata->pbufsize);
370 debug_print (3, ("SASL protection buffer size: %u\n", *sasldata->pbufsize));
372 /* clear input buffer */
373 sasldata->buf = NULL;
377 /* preserve old functions */
378 sasldata->sockdata = conn->sockdata;
379 sasldata->msasl_open = conn->conn_open;
380 sasldata->msasl_close = conn->conn_close;
381 sasldata->msasl_read = conn->conn_read;
382 sasldata->msasl_write = conn->conn_write;
384 /* and set up new functions */
385 conn->sockdata = sasldata;
386 conn->conn_open = mutt_sasl_conn_open;
387 conn->conn_close = mutt_sasl_conn_close;
388 conn->conn_read = mutt_sasl_conn_read;
389 conn->conn_write = mutt_sasl_conn_write;
392 void mutt_sasl_done (void) {
396 /* mutt_sasl_cb_log: callback to log SASL messages */
397 static int mutt_sasl_cb_log (void *context, int priority, const char *message)
399 debug_print (priority, ("SASL: %s\n", message));
404 /* mutt_sasl_cb_authname: callback to retrieve authname or user from ACCOUNT */
405 static int mutt_sasl_cb_authname (void *context, int id, const char **result,
408 ACCOUNT *account = (ACCOUNT *) context;
415 return SASL_BADPARAM;
417 debug_print (2, ("getting %s for %s:%u\n",
418 id == SASL_CB_AUTHNAME ? "authname" : "user",
419 account->host, account->port));
421 if (id == SASL_CB_AUTHNAME) {
422 if (mutt_account_getlogin (account))
424 *result = account->login;
426 if (mutt_account_getuser (account))
428 *result = account->user;
432 *len = m_strlen(*result);
437 static int mutt_sasl_cb_pass (sasl_conn_t * conn, void *context, int id,
438 sasl_secret_t ** psecret)
440 ACCOUNT *account = (ACCOUNT *) context;
443 if (!account || !psecret)
444 return SASL_BADPARAM;
446 debug_print (2, ("getting password for %s@%s:%u\n",
447 account->login, account->host, account->port));
449 if (mutt_account_getpass (account))
452 len = m_strlen(account->pass);
454 *psecret = xmalloc(sizeof(sasl_secret_t) + len);
455 (*psecret)->len = len;
456 strcpy ((char*) (*psecret)->data, account->pass); /* __STRCPY_CHECKED__ */
461 /* mutt_sasl_conn_open: empty wrapper for underlying open function. We
462 * don't know in advance that a connection will use SASL, so we
463 * replace conn's methods with sasl methods when authentication
464 * is successful, using mutt_sasl_setup_conn */
465 static int mutt_sasl_conn_open (CONNECTION * conn)
470 sasldata = (SASL_DATA *) conn->sockdata;
471 conn->sockdata = sasldata->sockdata;
472 rc = (sasldata->msasl_open) (conn);
473 conn->sockdata = sasldata;
478 /* mutt_sasl_conn_close: calls underlying close function and disposes of
479 * the sasl_conn_t object, then restores connection to pre-sasl state */
480 static int mutt_sasl_conn_close (CONNECTION * conn)
485 sasldata = (SASL_DATA *) conn->sockdata;
487 /* restore connection's underlying methods */
488 conn->sockdata = sasldata->sockdata;
489 conn->conn_open = sasldata->msasl_open;
490 conn->conn_close = sasldata->msasl_close;
491 conn->conn_read = sasldata->msasl_read;
492 conn->conn_write = sasldata->msasl_write;
494 /* release sasl resources */
495 sasl_dispose (&sasldata->saslconn);
496 p_delete(&sasldata->buf);
499 /* call underlying close */
500 rc = (conn->conn_close) (conn);
505 static int mutt_sasl_conn_read (CONNECTION * conn, char *buf, size_t len)
512 sasldata = (SASL_DATA *) conn->sockdata;
514 /* if we still have data in our read buffer, copy it into buf */
515 if (sasldata->blen > sasldata->bpos) {
516 olen = (sasldata->blen - sasldata->bpos > len) ? len :
517 sasldata->blen - sasldata->bpos;
519 memcpy (buf, sasldata->buf + sasldata->bpos, olen);
520 sasldata->bpos += olen;
525 conn->sockdata = sasldata->sockdata;
527 p_delete(&sasldata->buf);
531 /* and decode the result, if necessary */
532 if (*sasldata->ssf) {
534 /* call the underlying read function to fill the buffer */
535 rc = (sasldata->msasl_read) (conn, buf, len);
539 rc = sasl_decode (sasldata->saslconn, buf, rc, &sasldata->buf,
542 debug_print (1, ("SASL decode failed: %s\n",
543 sasl_errstring (rc, NULL, NULL)));
547 while (!sasldata->blen);
549 olen = (sasldata->blen - sasldata->bpos > len) ? len :
550 sasldata->blen - sasldata->bpos;
552 memcpy (buf, sasldata->buf, olen);
553 sasldata->bpos += olen;
558 rc = (sasldata->msasl_read) (conn, buf, len);
561 conn->sockdata = sasldata;
566 static int mutt_sasl_conn_write (CONNECTION * conn, const char *buf,
573 unsigned int olen, plen;
575 sasldata = (SASL_DATA *) conn->sockdata;
576 conn->sockdata = sasldata->sockdata;
578 /* encode data, if necessary */
579 if (*sasldata->ssf) {
580 /* handle data larger than MAXOUTBUF */
582 olen = (len > *sasldata->pbufsize) ? *sasldata->pbufsize : len;
584 rc = sasl_encode (sasldata->saslconn, buf, olen, &pbuf, &plen);
586 debug_print (1, ("SASL encoding failed: %s\n",
587 sasl_errstring (rc, NULL, NULL)));
591 rc = (sasldata->msasl_write) (conn, pbuf, plen);
599 while (len > *sasldata->pbufsize);
602 /* just write using the underlying socket function */
603 rc = (sasldata->msasl_write) (conn, buf, len);
605 conn->sockdata = sasldata;
610 conn->sockdata = sasldata;