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/lib-lib.h>
23 #include <lib-ui/curses.h>
24 #include <lib-sys/mutt_socket.h>
28 #include "mutt_sasl.h"
30 static int getnameinfo_err (int ret)
51 err = SASL_FAIL; /* no real equivalent */
54 err = SASL_FAIL; /* no real equivalent */
57 err = SASL_FAIL; /* no real equivalent */
63 /* arbitrary. SASL will probably use a smaller buffer anyway. OTOH it's
64 * been a while since I've had access to an SASL server which negotiated
65 * a protection buffer. */
66 #define M_SASL_MAXBUF 65536
68 #define IP_PORT_BUFLEN 1024
70 static sasl_callback_t mutt_sasl_callbacks[5];
72 static int mutt_sasl_start (void);
75 static int mutt_sasl_cb_authname (void *context, int id, const char **result,
77 static int mutt_sasl_cb_pass (sasl_conn_t * conn, void *context, int id,
78 sasl_secret_t ** psecret);
80 /* socket wrappers for a SASL security layer */
81 static int mutt_sasl_conn_open (CONNECTION * conn);
82 static int mutt_sasl_conn_close (CONNECTION * conn);
83 static int mutt_sasl_conn_read (CONNECTION * conn, char *buf, ssize_t len);
84 static int mutt_sasl_conn_write (CONNECTION * conn, const char *buf,
87 /* utility function, stolen from sasl2 sample code */
88 static int iptostring (const struct sockaddr *addr, socklen_t addrlen,
89 char *out, unsigned outlen)
91 char hbuf[NI_MAXHOST], pbuf[NI_MAXSERV];
97 ret = getnameinfo (addr, addrlen, hbuf, sizeof (hbuf), pbuf, sizeof (pbuf),
104 return getnameinfo_err (ret);
106 if (outlen < m_strlen(hbuf) + m_strlen(pbuf) + 2)
109 snprintf (out, outlen, "%s;%s", hbuf, pbuf);
114 /* mutt_sasl_cb_log: callback to log SASL messages */
115 static int mutt_sasl_cb_log (void *context, int priority, const char *message)
120 /* mutt_sasl_start: called before doing a SASL exchange - initialises library
122 int mutt_sasl_start (void)
124 static unsigned char sasl_init = 0;
126 static sasl_callback_t callbacks[2];
132 /* set up default logging callback */
133 callbacks[0].id = SASL_CB_LOG;
134 callbacks[0].proc = mutt_sasl_cb_log;
135 callbacks[0].context = NULL;
137 callbacks[1].id = SASL_CB_LIST_END;
138 callbacks[1].proc = NULL;
139 callbacks[1].context = NULL;
141 rc = sasl_client_init (callbacks);
152 /* mutt_sasl_client_new: wrapper for sasl_client_new which also sets various
153 * security properties. If this turns out to be fine for POP too we can
154 * probably stop exporting mutt_sasl_get_callbacks(). */
155 int mutt_sasl_client_new (CONNECTION * conn, sasl_conn_t ** saslconn)
157 sasl_security_properties_t secprops;
159 struct sockaddr_storage local, remote;
161 char iplocalport[IP_PORT_BUFLEN], ipremoteport[IP_PORT_BUFLEN];
165 if (mutt_sasl_start () != SASL_OK)
168 switch (conn->account.type) {
169 case M_ACCT_TYPE_IMAP:
172 case M_ACCT_TYPE_POP:
179 size = sizeof (local);
180 if (getsockname (conn->fd, (struct sockaddr *) &local, &size)) {
184 if (iptostring((struct sockaddr *)&local, size, iplocalport,
185 IP_PORT_BUFLEN) != SASL_OK) {
189 size = sizeof (remote);
190 if (getpeername (conn->fd, (struct sockaddr *) &remote, &size)) {
195 ((struct sockaddr *) &remote, size, ipremoteport,
196 IP_PORT_BUFLEN) != SASL_OK) {
200 rc = sasl_client_new(service, conn->account.host, iplocalport, ipremoteport,
201 mutt_sasl_get_callbacks(&conn->account), 0, saslconn);
207 /*** set sasl IP properties, necessary for use with krb4 ***/
208 /* Do we need to fail if this fails? I would assume having these unset
209 * would just disable KRB4. Who wrote this code?
212 struct sockaddr_in local, remote;
215 size = sizeof (local);
216 if (getsockname (conn->fd, (struct sockaddr *) &local, &size))
219 size = sizeof (remote);
220 if (getpeername (conn->fd, (struct sockaddr *) &remote, &size))
224 if (sasl_setprop (*saslconn, SASL_IP_LOCAL, &local) != SASL_OK) {
229 #ifdef SASL_IP_REMOTE
230 if (sasl_setprop (*saslconn, SASL_IP_REMOTE, &remote) != SASL_OK) {
236 /* set security properties. We use NOPLAINTEXT globally, since we can
237 * just fall back to LOGIN in the IMAP case anyway. If that doesn't
238 * work for POP, we can make it a flag or move this code into
239 * imap/auth_sasl.c */
240 p_clear(&secprops, 1);
241 /* Work around a casting bug in the SASL krb4 module */
242 secprops.max_ssf = 0x7fff;
243 secprops.maxbufsize = M_SASL_MAXBUF;
244 secprops.security_flags |= SASL_SEC_NOPLAINTEXT;
245 if (sasl_setprop (*saslconn, SASL_SEC_PROPS, &secprops) != SASL_OK) {
250 if (sasl_setprop (*saslconn, SASL_SSF_EXTERNAL, &(conn->ssf)) != SASL_OK)
254 if (sasl_setprop (*saslconn, SASL_AUTH_EXTERNAL, conn->account.user) !=
263 sasl_callback_t *mutt_sasl_get_callbacks (ACCOUNT * account)
265 sasl_callback_t *callback;
267 callback = mutt_sasl_callbacks;
269 callback->id = SASL_CB_USER;
270 callback->proc = mutt_sasl_cb_authname;
271 callback->context = account;
274 callback->id = SASL_CB_AUTHNAME;
275 callback->proc = mutt_sasl_cb_authname;
276 callback->context = account;
279 callback->id = SASL_CB_PASS;
280 callback->proc = mutt_sasl_cb_pass;
281 callback->context = account;
284 callback->id = SASL_CB_GETREALM;
285 callback->proc = NULL;
286 callback->context = NULL;
289 callback->id = SASL_CB_LIST_END;
290 callback->proc = NULL;
291 callback->context = NULL;
293 return mutt_sasl_callbacks;
296 int mutt_sasl_interact (sasl_interact_t * interaction)
298 char prompt[SHORT_STRING];
299 char resp[SHORT_STRING];
301 while (interaction->id != SASL_CB_LIST_END) {
302 snprintf (prompt, sizeof (prompt), "%s: ", interaction->prompt);
304 if (mutt_get_field (prompt, resp, sizeof (resp), 0))
307 interaction->len = m_strlen(resp) + 1;
308 interaction->result = p_dupstr(resp, interaction->len - 1);
315 /* SASL can stack a protection layer on top of an existing connection.
316 * To handle this, we store a saslconn_t in conn->sockdata, and write
317 * wrappers which en/decode the read/write stream, then replace sockdata
318 * with an embedded copy of the old sockdata and call the underlying
319 * functions (which we've also preserved). I thought about trying to make
320 * a general stackable connection system, but it seemed like overkill -
321 * something is wrong if we have 15 filters on top of a socket. Anyway,
322 * anything else which wishes to stack can use the same method. The only
323 * disadvantage is we have to write wrappers for all the socket methods,
324 * even if we only stack over read and write. Thinking about it, the
325 * abstraction problem is that there is more in CONNECTION than there
326 * needs to be. Ideally it would have only (void*)data and methods. */
328 /* mutt_sasl_setup_conn: replace connection methods, sockdata with
329 * SASL wrappers, for protection layers. Also get ssf, as a fastpath
330 * for the read/write methods. */
331 void mutt_sasl_setup_conn (CONNECTION * conn, sasl_conn_t * saslconn)
333 SASL_DATA *sasldata = p_new(SASL_DATA, 1);
335 sasldata->saslconn = saslconn;
336 /* get ssf so we know whether we have to (en|de)code read/write */
337 sasl_getprop (saslconn, SASL_SSF, (const void **)(void *)&sasldata->ssf);
339 /* Add SASL SSF to transport SSF */
340 conn->ssf += *sasldata->ssf;
341 sasl_getprop (saslconn, SASL_MAXOUTBUF,
342 (const void **)(void *)&sasldata->pbufsize);
344 /* clear input buffer */
345 sasldata->buf = NULL;
349 /* preserve old functions */
350 sasldata->sockdata = conn->sockdata;
351 sasldata->msasl_open = conn->conn_open;
352 sasldata->msasl_close = conn->conn_close;
353 sasldata->msasl_read = conn->conn_read;
354 sasldata->msasl_write = conn->conn_write;
356 /* and set up new functions */
357 conn->sockdata = sasldata;
358 conn->conn_open = mutt_sasl_conn_open;
359 conn->conn_close = mutt_sasl_conn_close;
360 conn->conn_read = mutt_sasl_conn_read;
361 conn->conn_write = mutt_sasl_conn_write;
364 void mutt_sasl_done (void) {
368 /* mutt_sasl_cb_authname: callback to retrieve authname or user from ACCOUNT */
369 static int mutt_sasl_cb_authname (void *context, int id, const char **result,
372 ACCOUNT *account = (ACCOUNT *) context;
379 return SASL_BADPARAM;
381 if (id == SASL_CB_AUTHNAME) {
382 if (mutt_account_getlogin (account))
384 *result = account->login;
386 if (mutt_account_getuser (account))
388 *result = account->user;
392 *len = m_strlen(*result);
397 static int mutt_sasl_cb_pass (sasl_conn_t * conn, void *context, int id,
398 sasl_secret_t ** psecret)
400 ACCOUNT *account = (ACCOUNT *) context;
403 if (!account || !psecret)
404 return SASL_BADPARAM;
406 if (mutt_account_getpass (account))
409 len = m_strlen(account->pass);
411 *psecret = xmalloc(sizeof(sasl_secret_t) + len);
412 (*psecret)->len = len;
413 strcpy ((char*) (*psecret)->data, account->pass); /* __STRCPY_CHECKED__ */
418 /* mutt_sasl_conn_open: empty wrapper for underlying open function. We
419 * don't know in advance that a connection will use SASL, so we
420 * replace conn's methods with sasl methods when authentication
421 * is successful, using mutt_sasl_setup_conn */
422 static int mutt_sasl_conn_open (CONNECTION * conn)
427 sasldata = (SASL_DATA *) conn->sockdata;
428 conn->sockdata = sasldata->sockdata;
429 rc = (sasldata->msasl_open) (conn);
430 conn->sockdata = sasldata;
435 /* mutt_sasl_conn_close: calls underlying close function and disposes of
436 * the sasl_conn_t object, then restores connection to pre-sasl state */
437 static int mutt_sasl_conn_close (CONNECTION * conn)
442 sasldata = (SASL_DATA *) conn->sockdata;
444 /* restore connection's underlying methods */
445 conn->sockdata = sasldata->sockdata;
446 conn->conn_open = sasldata->msasl_open;
447 conn->conn_close = sasldata->msasl_close;
448 conn->conn_read = sasldata->msasl_read;
449 conn->conn_write = sasldata->msasl_write;
451 /* release sasl resources */
452 sasl_dispose (&sasldata->saslconn);
453 p_delete(&sasldata->buf);
456 /* call underlying close */
457 rc = (conn->conn_close) (conn);
462 static int mutt_sasl_conn_read (CONNECTION * conn, char *buf, ssize_t len)
469 sasldata = (SASL_DATA *) conn->sockdata;
471 /* if we still have data in our read buffer, copy it into buf */
472 if (sasldata->blen > sasldata->bpos) {
473 olen = (sasldata->blen - sasldata->bpos > len) ? len :
474 sasldata->blen - sasldata->bpos;
476 memcpy (buf, sasldata->buf + sasldata->bpos, olen);
477 sasldata->bpos += olen;
482 conn->sockdata = sasldata->sockdata;
484 p_delete(&sasldata->buf);
488 /* and decode the result, if necessary */
489 if (*sasldata->ssf) {
491 /* call the underlying read function to fill the buffer */
492 rc = (sasldata->msasl_read) (conn, buf, len);
496 rc = sasl_decode (sasldata->saslconn, buf, rc, &sasldata->buf,
502 while (!sasldata->blen);
504 olen = (sasldata->blen - sasldata->bpos > len) ? len :
505 sasldata->blen - sasldata->bpos;
507 memcpy (buf, sasldata->buf, olen);
508 sasldata->bpos += olen;
513 rc = (sasldata->msasl_read) (conn, buf, len);
516 conn->sockdata = sasldata;
521 static int mutt_sasl_conn_write (CONNECTION * conn, const char *buf,
528 unsigned int olen, plen;
530 sasldata = (SASL_DATA *) conn->sockdata;
531 conn->sockdata = sasldata->sockdata;
533 /* encode data, if necessary */
534 if (*sasldata->ssf) {
535 /* handle data larger than MAXOUTBUF */
537 olen = (len > *sasldata->pbufsize) ? *sasldata->pbufsize : len;
539 rc = sasl_encode (sasldata->saslconn, buf, olen, &pbuf, &plen);
544 rc = (sasldata->msasl_write) (conn, pbuf, plen);
552 while (len > *sasldata->pbufsize);
555 /* just write using the underlying socket function */
556 rc = (sasldata->msasl_write) (conn, buf, len);
558 conn->sockdata = sasldata;
563 conn->sockdata = sasldata;