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 */
12 #include <lib-lib/lib-lib.h>
15 #include <sasl/sasl.h>
16 #include <sys/socket.h>
17 #include <netinet/in.h>
19 #include <lib-ui/curses.h>
20 #include <lib-sys/mutt_socket.h>
24 #include "mutt_sasl.h"
26 /* arbitrary. SASL will probably use a smaller buffer anyway. OTOH it's
27 * been a while since I've had access to an SASL server which negotiated
28 * a protection buffer. */
29 #define M_SASL_MAXBUF 65536
31 #define IP_PORT_BUFLEN 1024
33 static sasl_callback_t mutt_sasl_callbacks[5];
36 static int mutt_sasl_cb_authname (void *context, int id, const char **result,
38 static int mutt_sasl_cb_pass (sasl_conn_t * conn, void *context, int id,
39 sasl_secret_t ** psecret);
41 /* socket wrappers for a SASL security layer */
42 static int mutt_sasl_conn_open (CONNECTION * conn);
43 static int mutt_sasl_conn_close (CONNECTION * conn);
44 static int mutt_sasl_conn_read (CONNECTION * conn, char *buf, ssize_t len);
45 static int mutt_sasl_conn_write (CONNECTION * conn, const char *buf,
49 iptostring(const struct sockaddr_storage *addr, char *out, unsigned outlen)
51 char hbuf[NI_MAXHOST], pbuf[NI_MAXSERV];
53 if (getnameinfo((struct sockaddr*)addr, sizeof(*addr),
54 hbuf, sizeof(hbuf), pbuf, sizeof(pbuf),
55 NI_NUMERICHOST | NI_NUMERICSERV))
58 snprintf(out, outlen, "%s;%s", hbuf, pbuf);
62 /* mutt_sasl_start: called before doing a SASL exchange - initialises library
64 static int mutt_sasl_start (void)
66 static int sasl_init = 0;
71 if (sasl_client_init(NULL) != SASL_OK)
79 static sasl_callback_t *mutt_sasl_get_callbacks (ACCOUNT * account)
81 sasl_callback_t *callback;
83 callback = mutt_sasl_callbacks;
85 callback->id = SASL_CB_USER;
86 callback->proc = mutt_sasl_cb_authname;
87 callback->context = account;
90 callback->id = SASL_CB_AUTHNAME;
91 callback->proc = mutt_sasl_cb_authname;
92 callback->context = account;
95 callback->id = SASL_CB_PASS;
96 callback->proc = mutt_sasl_cb_pass;
97 callback->context = account;
100 callback->id = SASL_CB_GETREALM;
101 callback->proc = NULL;
102 callback->context = NULL;
105 callback->id = SASL_CB_LIST_END;
106 callback->proc = NULL;
107 callback->context = NULL;
109 return mutt_sasl_callbacks;
112 int mutt_sasl_client_new (CONNECTION * conn, sasl_conn_t ** saslconn)
114 sasl_security_properties_t secprops;
116 struct sockaddr_storage local, remote;
118 char iplocalport[IP_PORT_BUFLEN], ipremoteport[IP_PORT_BUFLEN];
122 if (mutt_sasl_start() != SASL_OK)
125 switch (conn->account.type) {
126 case M_ACCT_TYPE_IMAP:
130 case M_ACCT_TYPE_POP:
138 size = sizeof(local);
139 if (getsockname(conn->fd, (struct sockaddr *) &local, &size)
140 || iptostring(&local, iplocalport, IP_PORT_BUFLEN) != SASL_OK)
145 size = sizeof(remote);
146 if (getpeername(conn->fd, (struct sockaddr *) &remote, &size)
147 || iptostring(&remote, ipremoteport, IP_PORT_BUFLEN) != SASL_OK)
152 rc = sasl_client_new(service, conn->account.host, iplocalport,
154 mutt_sasl_get_callbacks(&conn->account), 0, saslconn);
160 /* set security properties. We use NOPLAINTEXT globally, since we can
161 * just fall back to LOGIN in the IMAP case anyway. If that doesn't
162 * work for POP, we can make it a flag or move this code into
163 * imap/auth_sasl.c */
164 p_clear(&secprops, 1);
165 /* Work around a casting bug in the SASL krb4 module */
166 secprops.max_ssf = 0x7fff;
167 secprops.maxbufsize = M_SASL_MAXBUF;
168 secprops.security_flags |= SASL_SEC_NOPLAINTEXT;
169 if (sasl_setprop (*saslconn, SASL_SEC_PROPS, &secprops) != SASL_OK) {
174 if (sasl_setprop (*saslconn, SASL_SSF_EXTERNAL, &(conn->ssf)) != SASL_OK)
178 if (sasl_setprop (*saslconn, SASL_AUTH_EXTERNAL, conn->account.user) !=
187 int mutt_sasl_interact (sasl_interact_t * interaction)
192 while (interaction->id != SASL_CB_LIST_END) {
193 snprintf (prompt, sizeof (prompt), "%s: ", interaction->prompt);
195 if (mutt_get_field (prompt, resp, sizeof (resp), 0))
198 interaction->len = m_strlen(resp) + 1;
199 interaction->result = p_dupstr(resp, interaction->len - 1);
206 /* SASL can stack a protection layer on top of an existing connection.
207 * To handle this, we store a saslconn_t in conn->sockdata, and write
208 * wrappers which en/decode the read/write stream, then replace sockdata
209 * with an embedded copy of the old sockdata and call the underlying
210 * functions (which we've also preserved). I thought about trying to make
211 * a general stackable connection system, but it seemed like overkill -
212 * something is wrong if we have 15 filters on top of a socket. Anyway,
213 * anything else which wishes to stack can use the same method. The only
214 * disadvantage is we have to write wrappers for all the socket methods,
215 * even if we only stack over read and write. Thinking about it, the
216 * abstraction problem is that there is more in CONNECTION than there
217 * needs to be. Ideally it would have only (void*)data and methods. */
219 /* mutt_sasl_setup_conn: replace connection methods, sockdata with
220 * SASL wrappers, for protection layers. Also get ssf, as a fastpath
221 * for the read/write methods. */
222 void mutt_sasl_setup_conn (CONNECTION * conn, sasl_conn_t * saslconn)
224 SASL_DATA *sasldata = p_new(SASL_DATA, 1);
226 sasldata->saslconn = saslconn;
227 /* get ssf so we know whether we have to (en|de)code read/write */
228 sasl_getprop (saslconn, SASL_SSF, (const void **)(void *)&sasldata->ssf);
230 /* Add SASL SSF to transport SSF */
231 conn->ssf += *sasldata->ssf;
232 sasl_getprop (saslconn, SASL_MAXOUTBUF,
233 (const void **)(void *)&sasldata->pbufsize);
235 /* clear input buffer */
236 sasldata->buf = NULL;
240 /* preserve old functions */
241 sasldata->sockdata = conn->sockdata;
242 sasldata->msasl_open = conn->conn_open;
243 sasldata->msasl_close = conn->conn_close;
244 sasldata->msasl_read = conn->conn_read;
245 sasldata->msasl_write = conn->conn_write;
247 /* and set up new functions */
248 conn->sockdata = sasldata;
249 conn->conn_open = mutt_sasl_conn_open;
250 conn->conn_close = mutt_sasl_conn_close;
251 conn->conn_read = mutt_sasl_conn_read;
252 conn->conn_write = mutt_sasl_conn_write;
255 void mutt_sasl_done (void) {
259 /* mutt_sasl_cb_authname: callback to retrieve authname or user from ACCOUNT */
260 static int mutt_sasl_cb_authname (void *context, int id, const char **result,
263 ACCOUNT *account = (ACCOUNT *) context;
270 return SASL_BADPARAM;
272 if (id == SASL_CB_AUTHNAME) {
273 if (mutt_account_getlogin (account))
275 *result = account->login;
277 if (mutt_account_getuser (account))
279 *result = account->user;
283 *len = m_strlen(*result);
288 static int mutt_sasl_cb_pass(sasl_conn_t *conn __attribute__ ((unused)),
289 void *context, int id __attribute__ ((unused)),
290 sasl_secret_t **psecret)
292 ACCOUNT *account = (ACCOUNT *) context;
295 if (!account || !psecret)
296 return SASL_BADPARAM;
298 if (mutt_account_getpass (account))
301 len = m_strlen(account->pass);
303 *psecret = xmalloc(sizeof(sasl_secret_t) + len);
304 (*psecret)->len = len;
305 memcpy((char*)(*psecret)->data, account->pass, len);
310 /* mutt_sasl_conn_open: empty wrapper for underlying open function. We
311 * don't know in advance that a connection will use SASL, so we
312 * replace conn's methods with sasl methods when authentication
313 * is successful, using mutt_sasl_setup_conn */
314 static int mutt_sasl_conn_open (CONNECTION * conn)
319 sasldata = (SASL_DATA *) conn->sockdata;
320 conn->sockdata = sasldata->sockdata;
321 rc = (sasldata->msasl_open) (conn);
322 conn->sockdata = sasldata;
327 /* mutt_sasl_conn_close: calls underlying close function and disposes of
328 * the sasl_conn_t object, then restores connection to pre-sasl state */
329 static int mutt_sasl_conn_close(CONNECTION * conn)
334 sasldata = (SASL_DATA *) conn->sockdata;
336 /* restore connection's underlying methods */
337 conn->sockdata = sasldata->sockdata;
338 conn->conn_open = sasldata->msasl_open;
339 conn->conn_close = sasldata->msasl_close;
340 conn->conn_read = sasldata->msasl_read;
341 conn->conn_write = sasldata->msasl_write;
343 /* release sasl resources */
344 sasl_dispose (&sasldata->saslconn);
345 p_delete(&sasldata->buf);
348 /* call underlying close */
349 rc = (conn->conn_close) (conn);
354 static int mutt_sasl_conn_read (CONNECTION * conn, char *buf, ssize_t len)
361 sasldata = (SASL_DATA *) conn->sockdata;
363 /* if we still have data in our read buffer, copy it into buf */
364 if (sasldata->blen > sasldata->bpos) {
365 olen = (sasldata->blen - sasldata->bpos > len) ? len :
366 sasldata->blen - sasldata->bpos;
368 memcpy (buf, sasldata->buf + sasldata->bpos, olen);
369 sasldata->bpos += olen;
374 conn->sockdata = sasldata->sockdata;
376 p_delete(&sasldata->buf);
380 /* and decode the result, if necessary */
381 if (*sasldata->ssf) {
383 /* call the underlying read function to fill the buffer */
384 rc = (sasldata->msasl_read) (conn, buf, len);
388 rc = sasl_decode(sasldata->saslconn, buf, rc,
389 (const char **)&sasldata->buf, &sasldata->blen);
394 while (!sasldata->blen);
396 olen = (sasldata->blen - sasldata->bpos > len) ? len :
397 sasldata->blen - sasldata->bpos;
399 memcpy (buf, sasldata->buf, olen);
400 sasldata->bpos += olen;
405 rc = (sasldata->msasl_read) (conn, buf, len);
408 conn->sockdata = sasldata;
414 mutt_sasl_conn_write(CONNECTION * conn, const char *buf, ssize_t len)
420 unsigned int olen, plen;
422 sasldata = (SASL_DATA *) conn->sockdata;
423 conn->sockdata = sasldata->sockdata;
425 /* encode data, if necessary */
426 if (*sasldata->ssf) {
427 /* handle data larger than MAXOUTBUF */
429 olen = (len > *sasldata->pbufsize) ? *sasldata->pbufsize : len;
431 rc = sasl_encode(sasldata->saslconn, buf, olen,
432 (const char **)&pbuf, &plen);
437 rc = (sasldata->msasl_write)(conn, pbuf, plen);
444 } while (len > *sasldata->pbufsize);
446 /* just write using the underlying socket function */
447 rc = (sasldata->msasl_write) (conn, buf, len);
450 conn->sockdata = sasldata;
455 conn->sockdata = sasldata;