fixing a bug in the retry loop for winbindd_pam_auth[_crap]()
[tprouty/samba.git] / source / nsswitch / winbindd_pam.c
1 /*
2    Unix SMB/CIFS implementation.
3
4    Winbind daemon - pam auth funcions
5
6    Copyright (C) Andrew Tridgell 2000
7    Copyright (C) Tim Potter 2001
8    Copyright (C) Andrew Bartlett 2001-2002
9    
10    This program is free software; you can redistribute it and/or modify
11    it under the terms of the GNU General Public License as published by
12    the Free Software Foundation; either version 2 of the License, or
13    (at your option) any later version.
14    
15    This program is distributed in the hope that it will be useful,
16    but WITHOUT ANY WARRANTY; without even the implied warranty of
17    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18    GNU General Public License for more details.
19    
20    You should have received a copy of the GNU General Public License
21    along with this program; if not, write to the Free Software
22    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
23 */
24
25 #include "winbindd.h"
26 #undef DBGC_CLASS
27 #define DBGC_CLASS DBGC_WINBIND
28
29
30 static NTSTATUS append_info3_as_ndr(TALLOC_CTX *mem_ctx, 
31                                     struct winbindd_cli_state *state, 
32                                     NET_USER_INFO_3 *info3) 
33 {
34         prs_struct ps;
35         uint32 size;
36         if (!prs_init(&ps, 256 /* Random, non-zero number */, mem_ctx, MARSHALL)) {
37                 return NT_STATUS_NO_MEMORY;
38         }
39         if (!net_io_user_info3("", info3, &ps, 1, 3)) {
40                 prs_mem_free(&ps);
41                 return NT_STATUS_UNSUCCESSFUL;
42         }
43
44         size = prs_data_size(&ps);
45         state->response.extra_data = malloc(size);
46         if (!state->response.extra_data) {
47                 prs_mem_free(&ps);
48                 return NT_STATUS_NO_MEMORY;
49         }
50         prs_copy_all_data_out(state->response.extra_data, &ps);
51         state->response.length += size;
52         prs_mem_free(&ps);
53         return NT_STATUS_OK;
54 }
55
56 /**********************************************************************
57  Authenticate a user with a clear test password
58 **********************************************************************/
59
60 enum winbindd_result winbindd_pam_auth(struct winbindd_cli_state *state) 
61 {
62         NTSTATUS result;
63         fstring name_domain, name_user;
64         unsigned char trust_passwd[16];
65         time_t last_change_time;
66         uint32 sec_channel_type;
67         NET_USER_INFO_3 info3;
68         struct cli_state *cli = NULL;
69         uchar chal[8];
70         TALLOC_CTX *mem_ctx = NULL;
71         DATA_BLOB lm_resp;
72         DATA_BLOB nt_resp;
73         DOM_CRED ret_creds;
74         int attempts = 0;
75         unsigned char local_lm_response[24];
76         unsigned char local_nt_response[24];
77         const char *contact_domain;
78         BOOL retry;
79
80         /* Ensure null termination */
81         state->request.data.auth.user[sizeof(state->request.data.auth.user)-1]='\0';
82
83         /* Ensure null termination */
84         state->request.data.auth.pass[sizeof(state->request.data.auth.pass)-1]='\0';
85
86         DEBUG(3, ("[%5lu]: pam auth %s\n", (unsigned long)state->pid,
87                   state->request.data.auth.user));
88
89         if (!(mem_ctx = talloc_init("winbind pam auth for %s", state->request.data.auth.user))) {
90                 DEBUG(0, ("winbindd_pam_auth: could not talloc_init()!\n"));
91                 result = NT_STATUS_NO_MEMORY;
92                 goto done;
93         }
94
95         /* Parse domain and username */
96         
97         parse_domain_user(state->request.data.auth.user, name_domain, name_user);
98         if ( !*name_domain ) {
99                 DEBUG(5,("no domain separator (%s) in username (%s) - failing auth\n", lp_winbind_separator(), state->request.data.auth.user));
100                 result = NT_STATUS_INVALID_PARAMETER;
101                 goto done;
102         }
103
104         /* do password magic */
105         
106         generate_random_buffer(chal, 8, False);
107         SMBencrypt(state->request.data.auth.pass, chal, local_lm_response);
108                 
109         SMBNTencrypt(state->request.data.auth.pass, chal, local_nt_response);
110
111         lm_resp = data_blob_talloc(mem_ctx, local_lm_response, sizeof(local_lm_response));
112         nt_resp = data_blob_talloc(mem_ctx, local_nt_response, sizeof(local_nt_response));
113         
114         if ( !get_trust_pw(name_domain, trust_passwd, &last_change_time, &sec_channel_type) ) {
115                 result = NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
116                 goto done;
117         }
118
119         /* what domain should we contact? */
120         
121         if ( IS_DC )
122                 contact_domain = name_domain;
123         else
124                 contact_domain = lp_workgroup();
125                 
126         /* check authentication loop */
127
128         do {
129                 ZERO_STRUCT(info3);
130                 ZERO_STRUCT(ret_creds);
131                 retry = False;
132         
133                 /* Don't shut this down - it belongs to the connection cache code */
134                 result = cm_get_netlogon_cli(contact_domain, trust_passwd, 
135                                              sec_channel_type, False, &cli);
136
137                 if (!NT_STATUS_IS_OK(result)) {
138                         DEBUG(3, ("could not open handle to NETLOGON pipe\n"));
139                         goto done;
140                 }
141
142                 result = cli_netlogon_sam_network_logon(cli, mem_ctx,
143                                                         &ret_creds,
144                                                         name_user, name_domain, 
145                                                         global_myname(), chal, 
146                                                         lm_resp, nt_resp,
147                                                         &info3);
148                 attempts += 1;
149                 
150                 /* We have to try a second time as cm_get_netlogon_cli
151                    might not yet have noticed that the DC has killed
152                    our connection. */
153
154                 if ( cli->fd == -1 ) {
155                         retry = True;
156                         continue;
157                 } 
158                 
159                 /* if we get access denied, a possible cuase was that we had and open
160                    connection to the DC, but someone changed our machine account password
161                    out from underneath us using 'net rpc changetrustpw' */
162                    
163                 if ( NT_STATUS_V(result) == NT_STATUS_V(NT_STATUS_ACCESS_DENIED) ) {
164                         DEBUG(3,("winbindd_pam_auth: sam_logon returned ACCESS_DENIED.  Maybe the trust account "
165                                 "password was changed and we didn't know it.  Killing connections to domain %s\n",
166                                 name_domain));
167                         winbindd_cm_flush();
168                         retry = True;
169                         cli = NULL;
170                 } 
171                 
172         } while ( (attempts < 2) && retry );
173         
174         clnt_deal_with_creds(cli->sess_key, &(cli->clnt_cred), &ret_creds);
175         
176         if (NT_STATUS_IS_OK(result)) {
177                 netsamlogon_cache_store( cli->mem_ctx, &info3 );
178                 wcache_invalidate_samlogon(find_domain_from_name(name_domain), &info3);
179         }
180    
181 done:
182         /* give us a more useful (more correct?) error code */
183         if ((NT_STATUS_EQUAL(result, NT_STATUS_DOMAIN_CONTROLLER_NOT_FOUND) || (NT_STATUS_EQUAL(result, NT_STATUS_UNSUCCESSFUL)))) {
184                 result = NT_STATUS_NO_LOGON_SERVERS;
185         }
186         
187         state->response.data.auth.nt_status = NT_STATUS_V(result);
188         fstrcpy(state->response.data.auth.nt_status_string, nt_errstr(result));
189         fstrcpy(state->response.data.auth.error_string, get_friendly_nt_error_msg(result));
190         state->response.data.auth.pam_error = nt_status_to_pam(result);
191
192         DEBUG(NT_STATUS_IS_OK(result) ? 5 : 2, ("Plain-text authentication for user %s returned %s (PAM: %d)\n", 
193               state->request.data.auth.user, 
194               state->response.data.auth.nt_status_string,
195               state->response.data.auth.pam_error));          
196
197         if (mem_ctx) 
198                 talloc_destroy(mem_ctx);
199         
200         return NT_STATUS_IS_OK(result) ? WINBINDD_OK : WINBINDD_ERROR;
201 }
202
203 /**********************************************************************
204  Challenge Response Authentication Protocol 
205 **********************************************************************/
206
207 enum winbindd_result winbindd_pam_auth_crap(struct winbindd_cli_state *state) 
208 {
209         NTSTATUS result;
210         unsigned char trust_passwd[16];
211         time_t last_change_time;
212         uint32 sec_channel_type;
213         NET_USER_INFO_3 info3;
214         struct cli_state *cli = NULL;
215         TALLOC_CTX *mem_ctx = NULL;
216         char *user = NULL;
217         const char *domain = NULL;
218         const char *workstation;
219         const char *contact_domain;
220         DOM_CRED ret_creds;
221         int attempts = 0;
222         BOOL retry;
223
224         DATA_BLOB lm_resp, nt_resp;
225
226         if (!state->privileged) {
227                 DEBUG(2, ("winbindd_pam_auth_crap: non-privileged access denied!\n"));
228                 /* send a better message than ACCESS_DENIED */
229                 push_utf8_fstring(state->response.data.auth.error_string, "winbind client not authorized to use winbindd_pam_auth_crap");
230                 result =  NT_STATUS_ACCESS_DENIED;
231                 goto done;
232         }
233
234         /* Ensure null termination */
235         state->request.data.auth_crap.user[sizeof(state->request.data.auth_crap.user)-1]=0;
236         state->request.data.auth_crap.domain[sizeof(state->request.data.auth_crap.domain)-1]=0;
237
238         if (!(mem_ctx = talloc_init("winbind pam auth crap for (utf8) %s", state->request.data.auth_crap.user))) {
239                 DEBUG(0, ("winbindd_pam_auth_crap: could not talloc_init()!\n"));
240                 result = NT_STATUS_NO_MEMORY;
241                 goto done;
242         }
243
244         if (pull_utf8_talloc(mem_ctx, &user, state->request.data.auth_crap.user) == (size_t)-1) {
245                 DEBUG(0, ("winbindd_pam_auth_crap: pull_utf8_talloc failed!\n"));
246                 result = NT_STATUS_UNSUCCESSFUL;
247                 goto done;
248         }
249
250         if (*state->request.data.auth_crap.domain) {
251                 char *dom = NULL;
252                 if (pull_utf8_talloc(mem_ctx, &dom, state->request.data.auth_crap.domain) == (size_t)-1) {
253                         DEBUG(0, ("winbindd_pam_auth_crap: pull_utf8_talloc failed!\n"));
254                         result = NT_STATUS_UNSUCCESSFUL;
255                         goto done;
256                 }
257                 domain = dom;
258         } else if (lp_winbind_use_default_domain()) {
259                 domain = lp_workgroup();
260         } else {
261                 DEBUG(5,("no domain specified with username (%s) - failing auth\n", 
262                          user));
263                 result = NT_STATUS_INVALID_PARAMETER;
264                 goto done;
265         }
266
267         DEBUG(3, ("[%5lu]: pam auth crap domain: %s user: %s\n", (unsigned long)state->pid,
268                   domain, user));
269            
270         if ( !get_trust_pw(domain, trust_passwd, &last_change_time, &sec_channel_type) ) {
271                 result = NT_STATUS_CANT_ACCESS_DOMAIN_INFO;
272                 goto done;
273         }
274
275         if (*state->request.data.auth_crap.workstation) {
276                 char *wrk = NULL;
277                 if (pull_utf8_talloc(mem_ctx, &wrk, state->request.data.auth_crap.workstation) == (size_t)-1) {
278                         DEBUG(0, ("winbindd_pam_auth_crap: pull_utf8_talloc failed!\n"));
279                         result = NT_STATUS_UNSUCCESSFUL;
280                         goto done;
281                 }
282                 workstation = wrk;
283         } else {
284                 workstation = global_myname();
285         }
286
287         if (state->request.data.auth_crap.lm_resp_len > sizeof(state->request.data.auth_crap.lm_resp)
288                 || state->request.data.auth_crap.nt_resp_len > sizeof(state->request.data.auth_crap.nt_resp)) {
289                 DEBUG(0, ("winbindd_pam_auth_crap: invalid password length %u/%u\n", 
290                           state->request.data.auth_crap.lm_resp_len, 
291                           state->request.data.auth_crap.nt_resp_len));
292                 result = NT_STATUS_INVALID_PARAMETER;
293                 goto done;
294         }
295
296         lm_resp = data_blob_talloc(mem_ctx, state->request.data.auth_crap.lm_resp, state->request.data.auth_crap.lm_resp_len);
297         nt_resp = data_blob_talloc(mem_ctx, state->request.data.auth_crap.nt_resp, state->request.data.auth_crap.nt_resp_len);
298         
299         /* what domain should we contact? */
300         
301         if ( IS_DC )
302                 contact_domain = domain;
303         else
304                 contact_domain = lp_workgroup();
305         
306         do {
307                 ZERO_STRUCT(info3);
308                 ZERO_STRUCT(ret_creds);
309                 retry = False;
310
311                 /* Don't shut this down - it belongs to the connection cache code */
312                 result = cm_get_netlogon_cli(contact_domain, trust_passwd, sec_channel_type, False, &cli);
313
314                 if (!NT_STATUS_IS_OK(result)) {
315                         DEBUG(3, ("could not open handle to NETLOGON pipe (error: %s)\n",
316                                   nt_errstr(result)));
317                         goto done;
318                 }
319
320                 result = cli_netlogon_sam_network_logon(cli, mem_ctx,
321                                                         &ret_creds,
322                                                         user, domain,
323                                                         workstation,
324                                                         state->request.data.auth_crap.chal, 
325                                                         lm_resp, nt_resp, 
326                                                         &info3);
327
328                 attempts += 1;
329
330                 /* We have to try a second time as cm_get_netlogon_cli
331                    might not yet have noticed that the DC has killed
332                    our connection. */
333
334                 if ( cli->fd == -1 ) {
335                         retry = True;
336                         continue;
337                 } 
338
339                 /* if we get access denied, a possible cause was that we had and open
340                    connection to the DC, but someone changed our machine account password
341                    out from underneath us using 'net rpc changetrustpw' */
342                    
343                 if ( NT_STATUS_V(result) == NT_STATUS_V(NT_STATUS_ACCESS_DENIED) ) {
344                         DEBUG(3,("winbindd_pam_auth_crap: sam_logon returned ACCESS_DENIED.  Maybe the trust account "
345                                 "password was changed and we didn't know it.  Killing connections to domain %s\n",
346                                 domain));
347                         winbindd_cm_flush();
348                         retry = True;
349                         cli = NULL;
350                 } 
351                 
352         } while ( (attempts < 2) && retry );
353
354         clnt_deal_with_creds(cli->sess_key, &(cli->clnt_cred), &ret_creds);
355         
356         if (NT_STATUS_IS_OK(result)) {
357                 netsamlogon_cache_store( cli->mem_ctx, &info3 );
358                 wcache_invalidate_samlogon(find_domain_from_name(domain), &info3);
359                 
360                 if (state->request.flags & WBFLAG_PAM_INFO3_NDR) {
361                         result = append_info3_as_ndr(mem_ctx, state, &info3);
362                 }
363                 
364                 if (state->request.flags & WBFLAG_PAM_NTKEY) {
365                         memcpy(state->response.data.auth.nt_session_key, info3.user_sess_key, sizeof(state->response.data.auth.nt_session_key) /* 16 */);
366                 }
367                 if (state->request.flags & WBFLAG_PAM_LMKEY) {
368                         memcpy(state->response.data.auth.first_8_lm_hash, info3.padding, sizeof(state->response.data.auth.first_8_lm_hash) /* 8 */);
369                 }
370         }
371
372 done:
373         /* give us a more useful (more correct?) error code */
374         if ((NT_STATUS_EQUAL(result, NT_STATUS_DOMAIN_CONTROLLER_NOT_FOUND) || (NT_STATUS_EQUAL(result, NT_STATUS_UNSUCCESSFUL)))) {
375                 result = NT_STATUS_NO_LOGON_SERVERS;
376         }
377         
378         state->response.data.auth.nt_status = NT_STATUS_V(result);
379         push_utf8_fstring(state->response.data.auth.nt_status_string, nt_errstr(result));
380         if (!*state->response.data.auth.error_string) 
381                 push_utf8_fstring(state->response.data.auth.error_string, get_friendly_nt_error_msg(result));
382         state->response.data.auth.pam_error = nt_status_to_pam(result);
383
384         DEBUG(NT_STATUS_IS_OK(result) ? 5 : 2, 
385               ("NTLM CRAP authentication for user [%s]\\[%s] returned %s (PAM: %d)\n", 
386                domain,
387                user,
388                state->response.data.auth.nt_status_string,
389                state->response.data.auth.pam_error));         
390
391         if (mem_ctx) 
392                 talloc_destroy(mem_ctx);
393         
394         return NT_STATUS_IS_OK(result) ? WINBINDD_OK : WINBINDD_ERROR;
395 }
396
397 /* Change a user password */
398
399 enum winbindd_result winbindd_pam_chauthtok(struct winbindd_cli_state *state)
400 {
401         NTSTATUS result;
402         char *oldpass, *newpass;
403         fstring domain, user;
404         CLI_POLICY_HND *hnd;
405
406         DEBUG(3, ("[%5lu]: pam chauthtok %s\n", (unsigned long)state->pid,
407                 state->request.data.chauthtok.user));
408
409         /* Setup crap */
410
411         if (state == NULL)
412                 return WINBINDD_ERROR;
413
414         parse_domain_user(state->request.data.chauthtok.user, domain, user);
415         if ( !*domain ) {
416                 result = NT_STATUS_INVALID_PARAMETER;
417                 goto done;
418         }
419
420         /* Change password */
421
422         oldpass = state->request.data.chauthtok.oldpass;
423         newpass = state->request.data.chauthtok.newpass;
424
425         /* Get sam handle */
426
427         if ( NT_STATUS_IS_ERR(result = cm_get_sam_handle(domain, &hnd)) ) {
428                 DEBUG(1, ("could not get SAM handle on DC for %s\n", domain));
429                 goto done;
430         }
431
432         if (!cli_oem_change_password(hnd->cli, user, newpass, oldpass)) {
433                 DEBUG(1, ("password change failed for user %s/%s\n", domain, 
434                           user));
435                 result = NT_STATUS_WRONG_PASSWORD;
436         } else {
437                 result = NT_STATUS_OK;
438         }
439
440 done:    
441         state->response.data.auth.nt_status = NT_STATUS_V(result);
442         fstrcpy(state->response.data.auth.nt_status_string, nt_errstr(result));
443         fstrcpy(state->response.data.auth.error_string, nt_errstr(result));
444         state->response.data.auth.pam_error = nt_status_to_pam(result);
445
446         DEBUG(NT_STATUS_IS_OK(result) ? 5 : 2, 
447               ("Password change for user [%s]\\[%s] returned %s (PAM: %d)\n", 
448                domain,
449                user,
450                state->response.data.auth.nt_status_string,
451                state->response.data.auth.pam_error));         
452
453         return NT_STATUS_IS_OK(result) ? WINBINDD_OK : WINBINDD_ERROR;
454 }