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>
26 #include "mutt_sasl.h"
27 #include <lib-sys/mutt_socket.h>
29 static int getnameinfo_err (int ret)
50 err = SASL_FAIL; /* no real equivalent */
53 err = SASL_FAIL; /* no real equivalent */
56 err = SASL_FAIL; /* no real equivalent */
62 /* arbitrary. SASL will probably use a smaller buffer anyway. OTOH it's
63 * been a while since I've had access to an SASL server which negotiated
64 * a protection buffer. */
65 #define M_SASL_MAXBUF 65536
67 #define IP_PORT_BUFLEN 1024
69 static sasl_callback_t mutt_sasl_callbacks[5];
71 static int mutt_sasl_start (void);
74 static int mutt_sasl_cb_authname (void *context, int id, const char **result,
76 static int mutt_sasl_cb_pass (sasl_conn_t * conn, void *context, int id,
77 sasl_secret_t ** psecret);
79 /* socket wrappers for a SASL security layer */
80 static int mutt_sasl_conn_open (CONNECTION * conn);
81 static int mutt_sasl_conn_close (CONNECTION * conn);
82 static int mutt_sasl_conn_read (CONNECTION * conn, char *buf, ssize_t len);
83 static int mutt_sasl_conn_write (CONNECTION * conn, const char *buf,
86 /* utility function, stolen from sasl2 sample code */
87 static int iptostring (const struct sockaddr *addr, socklen_t addrlen,
88 char *out, unsigned outlen)
90 char hbuf[NI_MAXHOST], pbuf[NI_MAXSERV];
96 ret = getnameinfo (addr, addrlen, hbuf, sizeof (hbuf), pbuf, sizeof (pbuf),
103 return getnameinfo_err (ret);
105 if (outlen < m_strlen(hbuf) + m_strlen(pbuf) + 2)
108 snprintf (out, outlen, "%s;%s", hbuf, pbuf);
113 /* mutt_sasl_cb_log: callback to log SASL messages */
114 static int mutt_sasl_cb_log (void *context, int priority, const char *message)
119 /* mutt_sasl_start: called before doing a SASL exchange - initialises library
121 int mutt_sasl_start (void)
123 static unsigned char sasl_init = 0;
125 static sasl_callback_t callbacks[2];
131 /* set up default logging callback */
132 callbacks[0].id = SASL_CB_LOG;
133 callbacks[0].proc = mutt_sasl_cb_log;
134 callbacks[0].context = NULL;
136 callbacks[1].id = SASL_CB_LIST_END;
137 callbacks[1].proc = NULL;
138 callbacks[1].context = NULL;
140 rc = sasl_client_init (callbacks);
151 /* mutt_sasl_client_new: wrapper for sasl_client_new which also sets various
152 * security properties. If this turns out to be fine for POP too we can
153 * probably stop exporting mutt_sasl_get_callbacks(). */
154 int mutt_sasl_client_new (CONNECTION * conn, sasl_conn_t ** saslconn)
156 sasl_security_properties_t secprops;
158 struct sockaddr_storage local, remote;
160 char iplocalport[IP_PORT_BUFLEN], ipremoteport[IP_PORT_BUFLEN];
164 if (mutt_sasl_start () != SASL_OK)
167 switch (conn->account.type) {
168 case M_ACCT_TYPE_IMAP:
171 case M_ACCT_TYPE_POP:
178 size = sizeof (local);
179 if (getsockname (conn->fd, (struct sockaddr *) &local, &size)) {
183 if (iptostring((struct sockaddr *)&local, size, iplocalport,
184 IP_PORT_BUFLEN) != SASL_OK) {
188 size = sizeof (remote);
189 if (getpeername (conn->fd, (struct sockaddr *) &remote, &size)) {
194 ((struct sockaddr *) &remote, size, ipremoteport,
195 IP_PORT_BUFLEN) != SASL_OK) {
199 rc = sasl_client_new(service, conn->account.host, iplocalport, ipremoteport,
200 mutt_sasl_get_callbacks(&conn->account), 0, saslconn);
206 /*** set sasl IP properties, necessary for use with krb4 ***/
207 /* Do we need to fail if this fails? I would assume having these unset
208 * would just disable KRB4. Who wrote this code?
211 struct sockaddr_in local, remote;
214 size = sizeof (local);
215 if (getsockname (conn->fd, (struct sockaddr *) &local, &size))
218 size = sizeof (remote);
219 if (getpeername (conn->fd, (struct sockaddr *) &remote, &size))
223 if (sasl_setprop (*saslconn, SASL_IP_LOCAL, &local) != SASL_OK) {
228 #ifdef SASL_IP_REMOTE
229 if (sasl_setprop (*saslconn, SASL_IP_REMOTE, &remote) != SASL_OK) {
235 /* set security properties. We use NOPLAINTEXT globally, since we can
236 * just fall back to LOGIN in the IMAP case anyway. If that doesn't
237 * work for POP, we can make it a flag or move this code into
238 * imap/auth_sasl.c */
239 p_clear(&secprops, 1);
240 /* Work around a casting bug in the SASL krb4 module */
241 secprops.max_ssf = 0x7fff;
242 secprops.maxbufsize = M_SASL_MAXBUF;
243 secprops.security_flags |= SASL_SEC_NOPLAINTEXT;
244 if (sasl_setprop (*saslconn, SASL_SEC_PROPS, &secprops) != SASL_OK) {
249 if (sasl_setprop (*saslconn, SASL_SSF_EXTERNAL, &(conn->ssf)) != SASL_OK)
253 if (sasl_setprop (*saslconn, SASL_AUTH_EXTERNAL, conn->account.user) !=
262 sasl_callback_t *mutt_sasl_get_callbacks (ACCOUNT * account)
264 sasl_callback_t *callback;
266 callback = mutt_sasl_callbacks;
268 callback->id = SASL_CB_USER;
269 callback->proc = mutt_sasl_cb_authname;
270 callback->context = account;
273 callback->id = SASL_CB_AUTHNAME;
274 callback->proc = mutt_sasl_cb_authname;
275 callback->context = account;
278 callback->id = SASL_CB_PASS;
279 callback->proc = mutt_sasl_cb_pass;
280 callback->context = account;
283 callback->id = SASL_CB_GETREALM;
284 callback->proc = NULL;
285 callback->context = NULL;
288 callback->id = SASL_CB_LIST_END;
289 callback->proc = NULL;
290 callback->context = NULL;
292 return mutt_sasl_callbacks;
295 int mutt_sasl_interact (sasl_interact_t * interaction)
297 char prompt[SHORT_STRING];
298 char resp[SHORT_STRING];
300 while (interaction->id != SASL_CB_LIST_END) {
301 snprintf (prompt, sizeof (prompt), "%s: ", interaction->prompt);
303 if (mutt_get_field (prompt, resp, sizeof (resp), 0))
306 interaction->len = m_strlen(resp) + 1;
307 interaction->result = p_dupstr(resp, interaction->len - 1);
314 /* SASL can stack a protection layer on top of an existing connection.
315 * To handle this, we store a saslconn_t in conn->sockdata, and write
316 * wrappers which en/decode the read/write stream, then replace sockdata
317 * with an embedded copy of the old sockdata and call the underlying
318 * functions (which we've also preserved). I thought about trying to make
319 * a general stackable connection system, but it seemed like overkill -
320 * something is wrong if we have 15 filters on top of a socket. Anyway,
321 * anything else which wishes to stack can use the same method. The only
322 * disadvantage is we have to write wrappers for all the socket methods,
323 * even if we only stack over read and write. Thinking about it, the
324 * abstraction problem is that there is more in CONNECTION than there
325 * needs to be. Ideally it would have only (void*)data and methods. */
327 /* mutt_sasl_setup_conn: replace connection methods, sockdata with
328 * SASL wrappers, for protection layers. Also get ssf, as a fastpath
329 * for the read/write methods. */
330 void mutt_sasl_setup_conn (CONNECTION * conn, sasl_conn_t * saslconn)
332 SASL_DATA *sasldata = p_new(SASL_DATA, 1);
334 sasldata->saslconn = saslconn;
335 /* get ssf so we know whether we have to (en|de)code read/write */
336 sasl_getprop (saslconn, SASL_SSF, (const void **)(void *)&sasldata->ssf);
338 /* Add SASL SSF to transport SSF */
339 conn->ssf += *sasldata->ssf;
340 sasl_getprop (saslconn, SASL_MAXOUTBUF,
341 (const void **)(void *)&sasldata->pbufsize);
343 /* clear input buffer */
344 sasldata->buf = NULL;
348 /* preserve old functions */
349 sasldata->sockdata = conn->sockdata;
350 sasldata->msasl_open = conn->conn_open;
351 sasldata->msasl_close = conn->conn_close;
352 sasldata->msasl_read = conn->conn_read;
353 sasldata->msasl_write = conn->conn_write;
355 /* and set up new functions */
356 conn->sockdata = sasldata;
357 conn->conn_open = mutt_sasl_conn_open;
358 conn->conn_close = mutt_sasl_conn_close;
359 conn->conn_read = mutt_sasl_conn_read;
360 conn->conn_write = mutt_sasl_conn_write;
363 void mutt_sasl_done (void) {
367 /* mutt_sasl_cb_authname: callback to retrieve authname or user from ACCOUNT */
368 static int mutt_sasl_cb_authname (void *context, int id, const char **result,
371 ACCOUNT *account = (ACCOUNT *) context;
378 return SASL_BADPARAM;
380 if (id == SASL_CB_AUTHNAME) {
381 if (mutt_account_getlogin (account))
383 *result = account->login;
385 if (mutt_account_getuser (account))
387 *result = account->user;
391 *len = m_strlen(*result);
396 static int mutt_sasl_cb_pass (sasl_conn_t * conn, void *context, int id,
397 sasl_secret_t ** psecret)
399 ACCOUNT *account = (ACCOUNT *) context;
402 if (!account || !psecret)
403 return SASL_BADPARAM;
405 if (mutt_account_getpass (account))
408 len = m_strlen(account->pass);
410 *psecret = xmalloc(sizeof(sasl_secret_t) + len);
411 (*psecret)->len = len;
412 strcpy ((char*) (*psecret)->data, account->pass); /* __STRCPY_CHECKED__ */
417 /* mutt_sasl_conn_open: empty wrapper for underlying open function. We
418 * don't know in advance that a connection will use SASL, so we
419 * replace conn's methods with sasl methods when authentication
420 * is successful, using mutt_sasl_setup_conn */
421 static int mutt_sasl_conn_open (CONNECTION * conn)
426 sasldata = (SASL_DATA *) conn->sockdata;
427 conn->sockdata = sasldata->sockdata;
428 rc = (sasldata->msasl_open) (conn);
429 conn->sockdata = sasldata;
434 /* mutt_sasl_conn_close: calls underlying close function and disposes of
435 * the sasl_conn_t object, then restores connection to pre-sasl state */
436 static int mutt_sasl_conn_close (CONNECTION * conn)
441 sasldata = (SASL_DATA *) conn->sockdata;
443 /* restore connection's underlying methods */
444 conn->sockdata = sasldata->sockdata;
445 conn->conn_open = sasldata->msasl_open;
446 conn->conn_close = sasldata->msasl_close;
447 conn->conn_read = sasldata->msasl_read;
448 conn->conn_write = sasldata->msasl_write;
450 /* release sasl resources */
451 sasl_dispose (&sasldata->saslconn);
452 p_delete(&sasldata->buf);
455 /* call underlying close */
456 rc = (conn->conn_close) (conn);
461 static int mutt_sasl_conn_read (CONNECTION * conn, char *buf, ssize_t len)
468 sasldata = (SASL_DATA *) conn->sockdata;
470 /* if we still have data in our read buffer, copy it into buf */
471 if (sasldata->blen > sasldata->bpos) {
472 olen = (sasldata->blen - sasldata->bpos > len) ? len :
473 sasldata->blen - sasldata->bpos;
475 memcpy (buf, sasldata->buf + sasldata->bpos, olen);
476 sasldata->bpos += olen;
481 conn->sockdata = sasldata->sockdata;
483 p_delete(&sasldata->buf);
487 /* and decode the result, if necessary */
488 if (*sasldata->ssf) {
490 /* call the underlying read function to fill the buffer */
491 rc = (sasldata->msasl_read) (conn, buf, len);
495 rc = sasl_decode (sasldata->saslconn, buf, rc, &sasldata->buf,
501 while (!sasldata->blen);
503 olen = (sasldata->blen - sasldata->bpos > len) ? len :
504 sasldata->blen - sasldata->bpos;
506 memcpy (buf, sasldata->buf, olen);
507 sasldata->bpos += olen;
512 rc = (sasldata->msasl_read) (conn, buf, len);
515 conn->sockdata = sasldata;
520 static int mutt_sasl_conn_write (CONNECTION * conn, const char *buf,
527 unsigned int olen, plen;
529 sasldata = (SASL_DATA *) conn->sockdata;
530 conn->sockdata = sasldata->sockdata;
532 /* encode data, if necessary */
533 if (*sasldata->ssf) {
534 /* handle data larger than MAXOUTBUF */
536 olen = (len > *sasldata->pbufsize) ? *sasldata->pbufsize : len;
538 rc = sasl_encode (sasldata->saslconn, buf, olen, &pbuf, &plen);
543 rc = (sasldata->msasl_write) (conn, pbuf, plen);
551 while (len > *sasldata->pbufsize);
554 /* just write using the underlying socket function */
555 rc = (sasldata->msasl_write) (conn, buf, len);
557 conn->sockdata = sasldata;
562 conn->sockdata = sasldata;