r4358: At metze's request, the Christmas elves have removed gensec_end in
[samba.git] / source4 / librpc / rpc / dcerpc_schannel.c
1 /* 
2    Unix SMB/CIFS implementation.
3
4    dcerpc schannel operations
5
6    Copyright (C) Andrew Tridgell 2004
7    
8    This program is free software; you can redistribute it and/or modify
9    it under the terms of the GNU General Public License as published by
10    the Free Software Foundation; either version 2 of the License, or
11    (at your option) any later version.
12    
13    This program is distributed in the hope that it will be useful,
14    but WITHOUT ANY WARRANTY; without even the implied warranty of
15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16    GNU General Public License for more details.
17    
18    You should have received a copy of the GNU General Public License
19    along with this program; if not, write to the Free Software
20    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
21 */
22
23 #include "includes.h"
24 #include "librpc/gen_ndr/ndr_schannel.h"
25 #include "auth/auth.h"
26
27 enum schannel_position {
28         DCERPC_SCHANNEL_STATE_START = 0,
29         DCERPC_SCHANNEL_STATE_UPDATE_1
30 };
31
32 struct dcerpc_schannel_state {
33         enum schannel_position state;
34         struct schannel_state *schannel_state;
35         struct creds_CredentialState *creds;
36         char *account_name;
37 };
38
39 static NTSTATUS dcerpc_schannel_key(struct dcerpc_pipe *p,
40                                     const char *domain,
41                                     const char *username,
42                                     const char *password,
43                                     int chan_type,
44                                     struct creds_CredentialState *creds);
45
46 /*
47   wrappers for the schannel_*() functions
48
49   These will become static again, when we get dynamic registration, and
50   decrpc_schannel_security_ops come back here.
51 */
52 static NTSTATUS dcerpc_schannel_unseal_packet(struct gensec_security *gensec_security, 
53                                               TALLOC_CTX *mem_ctx, 
54                                               uint8_t *data, size_t length, 
55                                               const uint8_t *whole_pdu, size_t pdu_length, 
56                                               DATA_BLOB *sig)
57 {
58         struct dcerpc_schannel_state *dce_schan_state = gensec_security->private_data;
59         
60         return schannel_unseal_packet(dce_schan_state->schannel_state, mem_ctx, data, length, sig);
61 }
62
63 static NTSTATUS dcerpc_schannel_check_packet(struct gensec_security *gensec_security, 
64                                              TALLOC_CTX *mem_ctx, 
65                                              const uint8_t *data, size_t length, 
66                                              const uint8_t *whole_pdu, size_t pdu_length, 
67                                              const DATA_BLOB *sig)
68 {
69         struct dcerpc_schannel_state *dce_schan_state = gensec_security->private_data;
70
71         return schannel_check_packet(dce_schan_state->schannel_state, data, length, sig);
72 }
73
74 static NTSTATUS dcerpc_schannel_seal_packet(struct gensec_security *gensec_security, 
75                                             TALLOC_CTX *mem_ctx, 
76                                             uint8_t *data, size_t length, 
77                                             const uint8_t *whole_pdu, size_t pdu_length, 
78                                             DATA_BLOB *sig)
79 {
80         struct dcerpc_schannel_state *dce_schan_state = gensec_security->private_data;
81
82         return schannel_seal_packet(dce_schan_state->schannel_state, mem_ctx, data, length, sig);
83 }
84
85 static NTSTATUS dcerpc_schannel_sign_packet(struct gensec_security *gensec_security, 
86                                             TALLOC_CTX *mem_ctx, 
87                                             const uint8_t *data, size_t length, 
88                                             const uint8_t *whole_pdu, size_t pdu_length, 
89                                             DATA_BLOB *sig)
90 {
91         struct dcerpc_schannel_state *dce_schan_state = gensec_security->private_data;
92
93         return schannel_sign_packet(dce_schan_state->schannel_state, mem_ctx, data, length, sig);
94 }
95
96 static size_t dcerpc_schannel_sig_size(struct gensec_security *gensec_security)
97 {
98         return 32;
99 }
100
101 static NTSTATUS dcerpc_schannel_session_key(struct gensec_security *gensec_security, 
102                                             DATA_BLOB *session_key)
103 {
104         return NT_STATUS_NOT_IMPLEMENTED;
105 }
106
107 static NTSTATUS dcerpc_schannel_update(struct gensec_security *gensec_security, TALLOC_CTX *out_mem_ctx, 
108                                        const DATA_BLOB in, DATA_BLOB *out) 
109 {
110         struct dcerpc_schannel_state *dce_schan_state = gensec_security->private_data;
111         NTSTATUS status;
112         struct schannel_bind bind_schannel;
113         struct schannel_bind_ack bind_schannel_ack;
114         const char *account_name;
115         *out = data_blob(NULL, 0);
116
117         switch (gensec_security->gensec_role) {
118         case GENSEC_CLIENT:
119                 if (dce_schan_state->state != DCERPC_SCHANNEL_STATE_START) {
120                         /* we could parse the bind ack, but we don't know what it is yet */
121                         return NT_STATUS_OK;
122                 }
123                 
124                 status = schannel_start(&dce_schan_state->schannel_state, 
125                                         dce_schan_state->creds->session_key,
126                                         True);
127                 if (!NT_STATUS_IS_OK(status)) {
128                         DEBUG(1, ("Failed to start schannel client\n"));
129                         return status;
130                 }
131                 talloc_steal(dce_schan_state, dce_schan_state->schannel_state);
132         
133                 bind_schannel.unknown1 = 0;
134 #if 0
135                 /* to support this we'd need to have access to the full domain name */
136                 bind_schannel.bind_type = 23;
137                 bind_schannel.u.info23.domain = gensec_security->user.domain;
138                 bind_schannel.u.info23.account_name = gensec_security->user.name;
139                 bind_schannel.u.info23.dnsdomain = str_format_nbt_domain(out_mem_ctx, fulldomainname);
140                 bind_schannel.u.info23.workstation = str_format_nbt_domain(out_mem_ctx, gensec_security->user.name);
141 #else
142                 bind_schannel.bind_type = 3;
143                 bind_schannel.u.info3.domain = gensec_security->user.domain;
144                 bind_schannel.u.info3.account_name = gensec_security->user.name;
145 #endif
146                 
147                 status = ndr_push_struct_blob(out, out_mem_ctx, &bind_schannel,
148                                               (ndr_push_flags_fn_t)ndr_push_schannel_bind);
149                 if (!NT_STATUS_IS_OK(status)) {
150                         DEBUG(3, ("Could not create schannel bind: %s\n",
151                                   nt_errstr(status)));
152                         return status;
153                 }
154                 
155                 dce_schan_state->state = DCERPC_SCHANNEL_STATE_UPDATE_1;
156
157                 return NT_STATUS_MORE_PROCESSING_REQUIRED;
158         case GENSEC_SERVER:
159                 
160                 if (dce_schan_state->state != DCERPC_SCHANNEL_STATE_START) {
161                         /* no third leg on this protocol */
162                         return NT_STATUS_INVALID_PARAMETER;
163                 }
164                 
165                 /* parse the schannel startup blob */
166                 status = ndr_pull_struct_blob(&in, out_mem_ctx, &bind_schannel, 
167                                               (ndr_pull_flags_fn_t)ndr_pull_schannel_bind);
168                 if (!NT_STATUS_IS_OK(status)) {
169                         return status;
170                 }
171                 
172                 if (bind_schannel.bind_type == 23) {
173                         account_name = bind_schannel.u.info23.account_name;
174                 } else {
175                         account_name = bind_schannel.u.info3.account_name;
176                 }
177                 
178                 /* pull the session key for this client */
179                 status = schannel_fetch_session_key(out_mem_ctx, account_name, &dce_schan_state->creds);
180                 if (!NT_STATUS_IS_OK(status)) {
181                         DEBUG(3, ("Could not find session key for attempted schannel connection on %s: %s\n",
182                                   account_name, nt_errstr(status)));
183                         return status;
184                 }
185
186                 dce_schan_state->account_name = talloc_strdup(dce_schan_state, account_name);
187                 
188                 /* start up the schannel server code */
189                 status = schannel_start(&dce_schan_state->schannel_state, 
190                                         dce_schan_state->creds->session_key, False);
191                 if (!NT_STATUS_IS_OK(status)) {
192                         DEBUG(3, ("Could not initialise schannel state for account %s: %s\n",
193                                   account_name, nt_errstr(status)));
194                         return status;
195                 }
196                 talloc_steal(dce_schan_state, dce_schan_state->schannel_state);
197                 
198                 bind_schannel_ack.unknown1 = 1;
199                 bind_schannel_ack.unknown2 = 0;
200                 bind_schannel_ack.unknown3 = 0x6c0000;
201                 
202                 status = ndr_push_struct_blob(out, out_mem_ctx, &bind_schannel_ack, 
203                                               (ndr_push_flags_fn_t)ndr_push_schannel_bind_ack);
204                 if (!NT_STATUS_IS_OK(status)) {
205                         DEBUG(3, ("Could not return schannel bind ack for account %s: %s\n",
206                                   account_name, nt_errstr(status)));
207                         return status;
208                 }
209
210                 dce_schan_state->state = DCERPC_SCHANNEL_STATE_UPDATE_1;
211
212                 return NT_STATUS_OK;
213         }
214         return NT_STATUS_INVALID_PARAMETER;
215 }
216
217 /** 
218  * Return the credentials of a logged on user, including session keys
219  * etc.
220  *
221  * Only valid after a successful authentication
222  *
223  * May only be called once per authentication.
224  *
225  */
226
227 NTSTATUS dcerpc_schannel_session_info(struct gensec_security *gensec_security,
228                                       struct auth_session_info **session_info)
229
230         struct dcerpc_schannel_state *dce_schan_state = gensec_security->private_data;
231
232         (*session_info) = talloc_p(gensec_security, struct auth_session_info);
233         if (*session_info == NULL) {
234                 return NT_STATUS_NO_MEMORY;
235         }
236
237         ZERO_STRUCTP(*session_info);
238         (*session_info)->refcount = 1;
239         
240         (*session_info)->workstation = talloc_strdup(*session_info, dce_schan_state->account_name);
241         if ((*session_info)->workstation == NULL) {
242                 talloc_free(*session_info);
243                 return NT_STATUS_NO_MEMORY;
244         }
245         return NT_STATUS_OK;
246 }
247                 
248
249 /**
250  * Return the struct creds_CredentialState.
251  *
252  * Make sure not to call this unless gensec is using schannel...
253  */
254
255 NTSTATUS dcerpc_schannel_creds(struct gensec_security *gensec_security,
256                                TALLOC_CTX *mem_ctx,
257                                struct creds_CredentialState **creds)
258
259         struct dcerpc_schannel_state *dce_schan_state = gensec_security->private_data;
260
261         *creds = talloc_reference(mem_ctx, dce_schan_state->creds);
262         if (!*creds) {
263                 return NT_STATUS_NO_MEMORY;
264         }
265         return NT_STATUS_OK;
266 }
267                 
268
269 /*
270   end crypto state
271 */
272 static int dcerpc_schannel_destroy(void *ptr)
273 {
274         struct dcerpc_schannel_state *dce_schan_state = ptr;
275
276         schannel_end(&dce_schan_state->schannel_state);
277
278         return 0;
279 }
280
281 static NTSTATUS dcerpc_schannel_start(struct gensec_security *gensec_security)
282 {
283         struct dcerpc_schannel_state *dce_schan_state;
284
285         dce_schan_state = talloc_p(gensec_security, struct dcerpc_schannel_state);
286         if (!dce_schan_state) {
287                 return NT_STATUS_NO_MEMORY;
288         }
289
290         dce_schan_state->state = DCERPC_SCHANNEL_STATE_START;
291         gensec_security->private_data = dce_schan_state;
292         gensec_security->have_features = 
293                 GENSEC_FEATURE_SESSION_KEY | 
294                 GENSEC_FEATURE_SIGN | 
295                 GENSEC_FEATURE_SEAL;
296
297         talloc_set_destructor(dce_schan_state, dcerpc_schannel_destroy);
298         
299         return NT_STATUS_OK;
300 }
301
302 static NTSTATUS dcerpc_schannel_server_start(struct gensec_security *gensec_security) 
303 {
304         NTSTATUS status;
305
306         status = dcerpc_schannel_start(gensec_security);
307         if (!NT_STATUS_IS_OK(status)) {
308                 return status;
309         }
310
311         return NT_STATUS_OK;
312 }
313
314 static NTSTATUS dcerpc_schannel_client_start(struct gensec_security *gensec_security) 
315 {
316         NTSTATUS status;
317
318         status = dcerpc_schannel_start(gensec_security);
319         if (!NT_STATUS_IS_OK(status)) {
320                 return status;
321         }
322
323         return NT_STATUS_OK;
324 }
325
326
327 /*
328   get a schannel key using a netlogon challenge on a secondary pipe
329 */
330 static NTSTATUS dcerpc_schannel_key(struct dcerpc_pipe *p,
331                                     const char *domain,
332                                     const char *username,
333                                     const char *password,
334                                     int chan_type,
335                                     struct creds_CredentialState *creds)
336 {
337         NTSTATUS status;
338         struct dcerpc_pipe *p2;
339         struct netr_ServerReqChallenge r;
340         struct netr_ServerAuthenticate2 a;
341         struct netr_Credential credentials1, credentials2, credentials3;
342         struct samr_Password mach_pwd;
343         const char *workgroup, *workstation;
344         uint32_t negotiate_flags;
345
346         if (p->flags & DCERPC_SCHANNEL_128) {
347                 negotiate_flags = NETLOGON_NEG_AUTH2_ADS_FLAGS;
348         } else {
349                 negotiate_flags = NETLOGON_NEG_AUTH2_FLAGS;
350         }
351
352         workstation = username;
353         workgroup = domain;
354
355         /*
356           step 1 - establish a netlogon connection, with no authentication
357         */
358         status = dcerpc_secondary_connection(p, &p2, 
359                                              DCERPC_NETLOGON_NAME, 
360                                              DCERPC_NETLOGON_UUID, 
361                                              DCERPC_NETLOGON_VERSION);
362         if (!NT_STATUS_IS_OK(status)) {
363                 return status;
364         }
365
366
367         /*
368           step 2 - request a netlogon challenge
369         */
370         r.in.server_name = talloc_asprintf(p, "\\\\%s", dcerpc_server_name(p));
371         r.in.computer_name = workstation;
372         r.in.credentials = &credentials1;
373         r.out.credentials = &credentials2;
374
375         generate_random_buffer(credentials1.data, sizeof(credentials1.data));
376
377         status = dcerpc_netr_ServerReqChallenge(p2, p, &r);
378         if (!NT_STATUS_IS_OK(status)) {
379                 return status;
380         }
381
382         /*
383           step 3 - authenticate on the netlogon pipe
384         */
385         E_md4hash(password, mach_pwd.hash);
386         creds_client_init(creds, &credentials1, &credentials2, &mach_pwd, &credentials3,
387                           negotiate_flags);
388
389         a.in.server_name = r.in.server_name;
390         a.in.account_name = talloc_asprintf(p, "%s$", workstation);
391         a.in.secure_channel_type = chan_type;
392         a.in.computer_name = workstation;
393         a.in.negotiate_flags = &negotiate_flags;
394         a.out.negotiate_flags = &negotiate_flags;
395         a.in.credentials = &credentials3;
396         a.out.credentials = &credentials3;
397
398         status = dcerpc_netr_ServerAuthenticate2(p2, p, &a);
399         if (!NT_STATUS_IS_OK(status)) {
400                 return status;
401         }
402
403         if (!creds_client_check(creds, a.out.credentials)) {
404                 return NT_STATUS_UNSUCCESSFUL;
405         }
406
407         /*
408           the schannel session key is now in creds.session_key
409
410           we no longer need the netlogon pipe open
411         */
412         dcerpc_pipe_close(p2);
413
414         return NT_STATUS_OK;
415 }
416
417 /*
418   do a schannel style bind on a dcerpc pipe. The username is usually
419   of the form HOSTNAME$ and the password is the domain trust password
420 */
421 NTSTATUS dcerpc_bind_auth_schannel_withkey(struct dcerpc_pipe *p,
422                                            const char *uuid, uint_t version,
423                                            const char *domain,
424                                            const char *username,
425                                            const char *password,
426                                            struct creds_CredentialState *creds)
427 {
428         NTSTATUS status;
429         struct dcerpc_schannel_state *dce_schan_state;
430
431         status = gensec_client_start(p, &p->security_state.generic_state);
432         if (!NT_STATUS_IS_OK(status)) {
433                 return status;
434         }
435
436         status = gensec_set_username(p->security_state.generic_state, username);
437         if (!NT_STATUS_IS_OK(status)) {
438                 DEBUG(1, ("Failed to set schannel username to %s: %s\n", username, nt_errstr(status)));
439                 talloc_free(p->security_state.generic_state);
440                 p->security_state.generic_state = NULL;
441                 return status;
442         }
443         
444         status = gensec_set_domain(p->security_state.generic_state, domain);
445         if (!NT_STATUS_IS_OK(status)) {
446                 DEBUG(1, ("Failed to set schannel domain to %s: %s\n", domain, nt_errstr(status)));
447                 talloc_free(p->security_state.generic_state);
448                 p->security_state.generic_state = NULL;
449                 return status;
450         }
451         
452         status = gensec_start_mech_by_authtype(p->security_state.generic_state, DCERPC_AUTH_TYPE_SCHANNEL, dcerpc_auth_level(p));
453
454         if (!NT_STATUS_IS_OK(status)) {
455                 DEBUG(1, ("Failed to start SCHANNEL GENSEC backend: %s\n", nt_errstr(status)));
456                 talloc_free(p->security_state.generic_state);
457                 p->security_state.generic_state = NULL;
458                 return status;
459         }
460
461         dce_schan_state = p->security_state.generic_state->private_data;
462         dce_schan_state->creds = talloc_reference(dce_schan_state, creds);
463
464         status = dcerpc_bind_auth3(p, DCERPC_AUTH_TYPE_SCHANNEL, dcerpc_auth_level(p),
465                                   uuid, version);
466
467         if (!NT_STATUS_IS_OK(status)) {
468                 DEBUG(1, ("Failed to bind to pipe with SCHANNEL: %s\n", nt_errstr(status)));
469                 talloc_free(p->security_state.generic_state);
470                 p->security_state.generic_state = NULL;
471                 return status;
472         }
473
474         return NT_STATUS_OK;
475 }
476
477 NTSTATUS dcerpc_bind_auth_schannel(struct dcerpc_pipe *p,
478                                    const char *uuid, uint_t version,
479                                    const char *domain,
480                                    const char *username,
481                                    const char *password)
482 {
483         NTSTATUS status;
484         int chan_type = 0;
485         struct creds_CredentialState *creds;
486         creds = talloc_p(p, struct creds_CredentialState);
487         if (!creds) {
488                 return NT_STATUS_NO_MEMORY;
489         }
490
491         if (p->flags & DCERPC_SCHANNEL_BDC) {
492                 chan_type = SEC_CHAN_BDC;
493         } else if (p->flags & DCERPC_SCHANNEL_WORKSTATION) {
494                 chan_type = SEC_CHAN_WKSTA;
495         } else if (p->flags & DCERPC_SCHANNEL_DOMAIN) {
496                 chan_type = SEC_CHAN_DOMAIN;
497         }
498
499         status = dcerpc_schannel_key(p, domain, 
500                                      username,
501                                      password, 
502                                      chan_type,
503                                      creds);
504
505         if (!NT_STATUS_IS_OK(status)) {
506                 DEBUG(1, ("Failed to fetch schannel session key: %s\n",
507                           nt_errstr(status)));
508                 return status;
509         }
510
511         return dcerpc_bind_auth_schannel_withkey(p, uuid, version, domain,
512                                                  username, password,
513                                                  creds);
514 }
515
516 static const struct gensec_security_ops gensec_dcerpc_schannel_security_ops = {
517         .name           = "dcerpc_schannel",
518         .auth_type      = DCERPC_AUTH_TYPE_SCHANNEL,
519         .client_start   = dcerpc_schannel_client_start,
520         .server_start   = dcerpc_schannel_server_start,
521         .update         = dcerpc_schannel_update,
522         .seal_packet    = dcerpc_schannel_seal_packet,
523         .sign_packet    = dcerpc_schannel_sign_packet,
524         .check_packet   = dcerpc_schannel_check_packet,
525         .unseal_packet  = dcerpc_schannel_unseal_packet,
526         .session_key    = dcerpc_schannel_session_key,
527         .session_info   = dcerpc_schannel_session_info,
528         .sig_size       = dcerpc_schannel_sig_size,
529 };
530
531 NTSTATUS gensec_dcerpc_schannel_init(void)
532 {
533         NTSTATUS ret;
534         ret = gensec_register(&gensec_dcerpc_schannel_security_ops);
535         if (!NT_STATUS_IS_OK(ret)) {
536                 DEBUG(0,("Failed to register '%s' gensec backend!\n",
537                         gensec_dcerpc_schannel_security_ops.name));
538                 return ret;
539         }
540
541         return ret;
542 }