s3 swat: Allow getting the user's HTTP auth password
[Samba.git] / source4 / kdc / kpasswdd.c
blob8f2cb6812989c4644d347b91feaa91d910524dac
1 /*
2 Unix SMB/CIFS implementation.
4 kpasswd Server implementation
6 Copyright (C) Andrew Bartlett <abartlet@samba.org> 2005
7 Copyright (C) Andrew Tridgell 2005
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 3 of the License, or
12 (at your option) any later version.
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with this program. If not, see <http://www.gnu.org/licenses/>.
23 #include "includes.h"
24 #include "smbd/service_task.h"
25 #include "lib/events/events.h"
26 #include "lib/socket/socket.h"
27 #include "system/network.h"
28 #include "../lib/util/dlinklist.h"
29 #include "lib/ldb/include/ldb.h"
30 #include "auth/gensec/gensec.h"
31 #include "auth/credentials/credentials.h"
32 #include "auth/credentials/credentials_krb5.h"
33 #include "auth/auth.h"
34 #include "dsdb/samdb/samdb.h"
35 #include "rpc_server/dcerpc_server.h"
36 #include "rpc_server/samr/proto.h"
37 #include "libcli/security/security.h"
38 #include "param/param.h"
39 #include "kdc/kdc.h"
41 /* TODO: remove all SAMBA4_INTERNAL_HEIMDAL stuff from this file */
42 #ifdef SAMBA4_INTERNAL_HEIMDAL
43 #include "heimdal_build/kpasswdd-glue.h"
44 #endif
46 /* hold information about one kdc socket */
47 struct kpasswd_socket {
48 struct socket_context *sock;
49 struct kdc_server *kdc;
50 struct tevent_fd *fde;
52 /* a queue of outgoing replies that have been deferred */
53 struct kdc_reply *send_queue;
56 /* Return true if there is a valid error packet formed in the error_blob */
57 static bool kpasswdd_make_error_reply(struct kdc_server *kdc,
58 TALLOC_CTX *mem_ctx,
59 uint16_t result_code,
60 const char *error_string,
61 DATA_BLOB *error_blob)
63 char *error_string_utf8;
64 size_t len;
66 DEBUG(result_code ? 3 : 10, ("kpasswdd: %s\n", error_string));
68 if (!push_utf8_talloc(mem_ctx, &error_string_utf8, error_string, &len)) {
69 return false;
72 *error_blob = data_blob_talloc(mem_ctx, NULL, 2 + len + 1);
73 if (!error_blob->data) {
74 return false;
76 RSSVAL(error_blob->data, 0, result_code);
77 memcpy(error_blob->data + 2, error_string_utf8, len + 1);
78 return true;
81 /* Return true if there is a valid error packet formed in the error_blob */
82 static bool kpasswdd_make_unauth_error_reply(struct kdc_server *kdc,
83 TALLOC_CTX *mem_ctx,
84 uint16_t result_code,
85 const char *error_string,
86 DATA_BLOB *error_blob)
88 bool ret;
89 int kret;
90 DATA_BLOB error_bytes;
91 krb5_data k5_error_bytes, k5_error_blob;
92 ret = kpasswdd_make_error_reply(kdc, mem_ctx, result_code, error_string,
93 &error_bytes);
94 if (!ret) {
95 return false;
97 k5_error_bytes.data = error_bytes.data;
98 k5_error_bytes.length = error_bytes.length;
99 kret = krb5_mk_error(kdc->smb_krb5_context->krb5_context,
100 result_code, NULL, &k5_error_bytes,
101 NULL, NULL, NULL, NULL, &k5_error_blob);
102 if (kret) {
103 return false;
105 *error_blob = data_blob_talloc(mem_ctx, k5_error_blob.data, k5_error_blob.length);
106 krb5_data_free(&k5_error_blob);
107 if (!error_blob->data) {
108 return false;
110 return true;
113 static bool kpasswd_make_pwchange_reply(struct kdc_server *kdc,
114 TALLOC_CTX *mem_ctx,
115 NTSTATUS status,
116 enum samr_RejectReason reject_reason,
117 struct samr_DomInfo1 *dominfo,
118 DATA_BLOB *error_blob)
120 if (NT_STATUS_EQUAL(status, NT_STATUS_NO_SUCH_USER)) {
121 return kpasswdd_make_error_reply(kdc, mem_ctx,
122 KRB5_KPASSWD_ACCESSDENIED,
123 "No such user when changing password",
124 error_blob);
126 if (NT_STATUS_EQUAL(status, NT_STATUS_ACCESS_DENIED)) {
127 return kpasswdd_make_error_reply(kdc, mem_ctx,
128 KRB5_KPASSWD_ACCESSDENIED,
129 "Not permitted to change password",
130 error_blob);
132 if (dominfo && NT_STATUS_EQUAL(status, NT_STATUS_PASSWORD_RESTRICTION)) {
133 const char *reject_string;
134 switch (reject_reason) {
135 case SAMR_REJECT_TOO_SHORT:
136 reject_string = talloc_asprintf(mem_ctx, "Password too short, password must be at least %d characters long",
137 dominfo->min_password_length);
138 break;
139 case SAMR_REJECT_COMPLEXITY:
140 reject_string = "Password does not meet complexity requirements";
141 break;
142 case SAMR_REJECT_IN_HISTORY:
143 reject_string = "Password is already in password history";
144 break;
145 case SAMR_REJECT_OTHER:
146 default:
147 reject_string = talloc_asprintf(mem_ctx, "Password must be at least %d characters long, and cannot match any of your %d previous passwords",
148 dominfo->min_password_length, dominfo->password_history_length);
149 break;
151 return kpasswdd_make_error_reply(kdc, mem_ctx,
152 KRB5_KPASSWD_SOFTERROR,
153 reject_string,
154 error_blob);
156 if (!NT_STATUS_IS_OK(status)) {
157 return kpasswdd_make_error_reply(kdc, mem_ctx,
158 KRB5_KPASSWD_HARDERROR,
159 talloc_asprintf(mem_ctx, "failed to set password: %s", nt_errstr(status)),
160 error_blob);
163 return kpasswdd_make_error_reply(kdc, mem_ctx, KRB5_KPASSWD_SUCCESS,
164 "Password changed",
165 error_blob);
169 A user password change
171 Return true if there is a valid error packet (or sucess) formed in
172 the error_blob
174 static bool kpasswdd_change_password(struct kdc_server *kdc,
175 TALLOC_CTX *mem_ctx,
176 struct auth_session_info *session_info,
177 const DATA_BLOB *password,
178 DATA_BLOB *reply)
180 NTSTATUS status;
181 enum samr_RejectReason reject_reason;
182 struct samr_DomInfo1 *dominfo;
183 struct ldb_context *samdb;
185 samdb = samdb_connect(mem_ctx, kdc->task->event_ctx, kdc->task->lp_ctx, system_session(mem_ctx, kdc->task->lp_ctx));
186 if (!samdb) {
187 return kpasswdd_make_error_reply(kdc, mem_ctx,
188 KRB5_KPASSWD_HARDERROR,
189 "Failed to open samdb",
190 reply);
193 DEBUG(3, ("Changing password of %s\\%s (%s)\n",
194 session_info->server_info->domain_name,
195 session_info->server_info->account_name,
196 dom_sid_string(mem_ctx, session_info->security_token->user_sid)));
198 /* User password change */
199 status = samdb_set_password_sid(samdb, mem_ctx,
200 session_info->security_token->user_sid,
201 password, NULL, NULL,
202 true, /* this is a user password change */
203 &reject_reason,
204 &dominfo);
205 return kpasswd_make_pwchange_reply(kdc, mem_ctx,
206 status,
207 reject_reason,
208 dominfo,
209 reply);
213 static bool kpasswd_process_request(struct kdc_server *kdc,
214 TALLOC_CTX *mem_ctx,
215 struct gensec_security *gensec_security,
216 uint16_t version,
217 DATA_BLOB *input,
218 DATA_BLOB *reply)
220 struct auth_session_info *session_info;
221 size_t pw_len;
223 if (!NT_STATUS_IS_OK(gensec_session_info(gensec_security,
224 &session_info))) {
225 return kpasswdd_make_error_reply(kdc, mem_ctx,
226 KRB5_KPASSWD_HARDERROR,
227 "gensec_session_info failed!",
228 reply);
231 switch (version) {
232 case KRB5_KPASSWD_VERS_CHANGEPW:
234 DATA_BLOB password;
235 if (!convert_string_talloc_convenience(mem_ctx, lp_iconv_convenience(kdc->task->lp_ctx),
236 CH_UTF8, CH_UTF16,
237 (const char *)input->data,
238 input->length,
239 (void **)&password.data, &pw_len, false)) {
240 return false;
242 password.length = pw_len;
244 return kpasswdd_change_password(kdc, mem_ctx, session_info,
245 &password, reply);
246 break;
248 case KRB5_KPASSWD_VERS_SETPW:
250 NTSTATUS status;
251 enum samr_RejectReason reject_reason = SAMR_REJECT_OTHER;
252 struct samr_DomInfo1 *dominfo = NULL;
253 struct ldb_context *samdb;
254 struct ldb_message *msg;
255 krb5_context context = kdc->smb_krb5_context->krb5_context;
257 ChangePasswdDataMS chpw;
258 DATA_BLOB password;
260 krb5_principal principal;
261 char *set_password_on_princ;
262 struct ldb_dn *set_password_on_dn;
264 size_t len;
265 int ret;
267 msg = ldb_msg_new(mem_ctx);
268 if (!msg) {
269 return false;
272 ret = decode_ChangePasswdDataMS(input->data, input->length,
273 &chpw, &len);
274 if (ret) {
275 return kpasswdd_make_error_reply(kdc, mem_ctx,
276 KRB5_KPASSWD_MALFORMED,
277 "failed to decode password change structure",
278 reply);
281 if (!convert_string_talloc_convenience(mem_ctx, lp_iconv_convenience(kdc->task->lp_ctx),
282 CH_UTF8, CH_UTF16,
283 (const char *)chpw.newpasswd.data,
284 chpw.newpasswd.length,
285 (void **)&password.data, &pw_len, false)) {
286 free_ChangePasswdDataMS(&chpw);
287 return false;
290 password.length = pw_len;
292 if ((chpw.targname && !chpw.targrealm)
293 || (!chpw.targname && chpw.targrealm)) {
294 return kpasswdd_make_error_reply(kdc, mem_ctx,
295 KRB5_KPASSWD_MALFORMED,
296 "Realm and principal must be both present, or neither present",
297 reply);
299 if (chpw.targname && chpw.targrealm) {
300 #ifdef SAMBA4_INTERNAL_HEIMDAL
301 if (_krb5_principalname2krb5_principal(kdc->smb_krb5_context->krb5_context,
302 &principal, *chpw.targname,
303 *chpw.targrealm) != 0) {
304 free_ChangePasswdDataMS(&chpw);
305 return kpasswdd_make_error_reply(kdc, mem_ctx,
306 KRB5_KPASSWD_MALFORMED,
307 "failed to extract principal to set",
308 reply);
311 #else /* SAMBA4_INTERNAL_HEIMDAL */
312 return kpasswdd_make_error_reply(kdc, mem_ctx,
313 KRB5_KPASSWD_BAD_VERSION,
314 "Operation Not Implemented",
315 reply);
316 #endif /* SAMBA4_INTERNAL_HEIMDAL */
317 } else {
318 free_ChangePasswdDataMS(&chpw);
319 return kpasswdd_change_password(kdc, mem_ctx, session_info,
320 &password, reply);
322 free_ChangePasswdDataMS(&chpw);
324 if (krb5_unparse_name(context, principal, &set_password_on_princ) != 0) {
325 krb5_free_principal(context, principal);
326 return kpasswdd_make_error_reply(kdc, mem_ctx,
327 KRB5_KPASSWD_MALFORMED,
328 "krb5_unparse_name failed!",
329 reply);
332 krb5_free_principal(context, principal);
334 samdb = samdb_connect(mem_ctx, kdc->task->event_ctx, kdc->task->lp_ctx, session_info);
335 if (!samdb) {
336 return kpasswdd_make_error_reply(kdc, mem_ctx,
337 KRB5_KPASSWD_HARDERROR,
338 "Unable to open database!",
339 reply);
342 DEBUG(3, ("%s\\%s (%s) is changing password of %s\n",
343 session_info->server_info->domain_name,
344 session_info->server_info->account_name,
345 dom_sid_string(mem_ctx, session_info->security_token->user_sid),
346 set_password_on_princ));
347 ret = ldb_transaction_start(samdb);
348 if (ret) {
349 status = NT_STATUS_TRANSACTION_ABORTED;
350 return kpasswd_make_pwchange_reply(kdc, mem_ctx,
351 status,
352 SAMR_REJECT_OTHER,
353 NULL,
354 reply);
357 status = crack_user_principal_name(samdb, mem_ctx,
358 set_password_on_princ,
359 &set_password_on_dn, NULL);
360 free(set_password_on_princ);
361 if (!NT_STATUS_IS_OK(status)) {
362 ldb_transaction_cancel(samdb);
363 return kpasswd_make_pwchange_reply(kdc, mem_ctx,
364 status,
365 SAMR_REJECT_OTHER,
366 NULL,
367 reply);
370 msg = ldb_msg_new(mem_ctx);
371 if (msg == NULL) {
372 ldb_transaction_cancel(samdb);
373 status = NT_STATUS_NO_MEMORY;
374 } else {
375 msg->dn = ldb_dn_copy(msg, set_password_on_dn);
376 if (!msg->dn) {
377 status = NT_STATUS_NO_MEMORY;
381 if (NT_STATUS_IS_OK(status)) {
382 /* Admin password set */
383 status = samdb_set_password(samdb, mem_ctx,
384 set_password_on_dn, NULL,
385 msg, &password, NULL, NULL,
386 false, /* this is not a user password change */
387 &reject_reason, &dominfo);
390 if (NT_STATUS_IS_OK(status)) {
391 /* modify the samdb record */
392 ret = samdb_replace(samdb, mem_ctx, msg);
393 if (ret != 0) {
394 DEBUG(2,("Failed to modify record to set password on %s: %s\n",
395 ldb_dn_get_linearized(msg->dn),
396 ldb_errstring(samdb)));
397 status = NT_STATUS_ACCESS_DENIED;
400 if (NT_STATUS_IS_OK(status)) {
401 ret = ldb_transaction_commit(samdb);
402 if (ret != 0) {
403 DEBUG(1,("Failed to commit transaction to set password on %s: %s\n",
404 ldb_dn_get_linearized(msg->dn),
405 ldb_errstring(samdb)));
406 status = NT_STATUS_TRANSACTION_ABORTED;
408 } else {
409 ldb_transaction_cancel(samdb);
411 return kpasswd_make_pwchange_reply(kdc, mem_ctx,
412 status,
413 reject_reason,
414 dominfo,
415 reply);
417 default:
418 return kpasswdd_make_error_reply(kdc, mem_ctx,
419 KRB5_KPASSWD_BAD_VERSION,
420 talloc_asprintf(mem_ctx,
421 "Protocol version %u not supported",
422 version),
423 reply);
425 return true;
428 bool kpasswdd_process(struct kdc_server *kdc,
429 TALLOC_CTX *mem_ctx,
430 DATA_BLOB *input,
431 DATA_BLOB *reply,
432 struct socket_address *peer_addr,
433 struct socket_address *my_addr,
434 int datagram_reply)
436 bool ret;
437 const uint16_t header_len = 6;
438 uint16_t len;
439 uint16_t ap_req_len;
440 uint16_t krb_priv_len;
441 uint16_t version;
442 NTSTATUS nt_status;
443 DATA_BLOB ap_req, krb_priv_req;
444 DATA_BLOB krb_priv_rep = data_blob(NULL, 0);
445 DATA_BLOB ap_rep = data_blob(NULL, 0);
446 DATA_BLOB kpasswd_req, kpasswd_rep;
447 struct cli_credentials *server_credentials;
448 struct gensec_security *gensec_security;
449 TALLOC_CTX *tmp_ctx = talloc_new(mem_ctx);
451 if (!tmp_ctx) {
452 return false;
455 /* Be parinoid. We need to ensure we don't just let the
456 * caller lead us into a buffer overflow */
457 if (input->length <= header_len) {
458 talloc_free(tmp_ctx);
459 return false;
462 len = RSVAL(input->data, 0);
463 if (input->length != len) {
464 talloc_free(tmp_ctx);
465 return false;
468 /* There are two different versions of this protocol so far,
469 * plus others in the standards pipe. Fortunetly they all
470 * take a very similar framing */
471 version = RSVAL(input->data, 2);
472 ap_req_len = RSVAL(input->data, 4);
473 if ((ap_req_len >= len) || (ap_req_len + header_len) >= len) {
474 talloc_free(tmp_ctx);
475 return false;
478 krb_priv_len = len - ap_req_len;
479 ap_req = data_blob_const(&input->data[header_len], ap_req_len);
480 krb_priv_req = data_blob_const(&input->data[header_len + ap_req_len], krb_priv_len);
482 server_credentials = cli_credentials_init(tmp_ctx);
483 if (!server_credentials) {
484 DEBUG(1, ("Failed to init server credentials\n"));
485 return false;
488 /* We want the credentials subsystem to use the krb5 context
489 * we already have, rather than a new context */
490 cli_credentials_set_krb5_context(server_credentials, kdc->smb_krb5_context);
491 cli_credentials_set_conf(server_credentials, kdc->task->lp_ctx);
492 nt_status = cli_credentials_set_stored_principal(server_credentials, kdc->task->event_ctx, kdc->task->lp_ctx, "kadmin/changepw");
493 if (!NT_STATUS_IS_OK(nt_status)) {
494 ret = kpasswdd_make_unauth_error_reply(kdc, mem_ctx,
495 KRB5_KPASSWD_HARDERROR,
496 talloc_asprintf(mem_ctx,
497 "Failed to obtain server credentials for kadmin/changepw: %s\n",
498 nt_errstr(nt_status)),
499 &krb_priv_rep);
500 ap_rep.length = 0;
501 if (ret) {
502 goto reply;
504 talloc_free(tmp_ctx);
505 return ret;
508 /* We don't strictly need to call this wrapper, and could call
509 * gensec_server_start directly, as we have no need for NTLM
510 * and we have a PAC, but this ensures that the wrapper can be
511 * safely extended for other helpful things in future */
512 nt_status = samba_server_gensec_start(tmp_ctx, kdc->task->event_ctx,
513 kdc->task->msg_ctx,
514 kdc->task->lp_ctx,
515 server_credentials,
516 "kpasswd",
517 &gensec_security);
518 if (!NT_STATUS_IS_OK(nt_status)) {
519 talloc_free(tmp_ctx);
520 return false;
523 /* The kerberos PRIV packets include these addresses. MIT
524 * clients check that they are present */
525 nt_status = gensec_set_peer_addr(gensec_security, peer_addr);
526 if (!NT_STATUS_IS_OK(nt_status)) {
527 talloc_free(tmp_ctx);
528 return false;
530 nt_status = gensec_set_my_addr(gensec_security, my_addr);
531 if (!NT_STATUS_IS_OK(nt_status)) {
532 talloc_free(tmp_ctx);
533 return false;
536 /* We want the GENSEC wrap calls to generate PRIV tokens */
537 gensec_want_feature(gensec_security, GENSEC_FEATURE_SEAL);
539 nt_status = gensec_start_mech_by_name(gensec_security, "krb5");
540 if (!NT_STATUS_IS_OK(nt_status)) {
541 talloc_free(tmp_ctx);
542 return false;
545 /* Accept the AP-REQ and generate teh AP-REP we need for the reply */
546 nt_status = gensec_update(gensec_security, tmp_ctx, ap_req, &ap_rep);
547 if (!NT_STATUS_IS_OK(nt_status) && !NT_STATUS_EQUAL(nt_status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
549 ret = kpasswdd_make_unauth_error_reply(kdc, mem_ctx,
550 KRB5_KPASSWD_HARDERROR,
551 talloc_asprintf(mem_ctx,
552 "gensec_update failed: %s",
553 nt_errstr(nt_status)),
554 &krb_priv_rep);
555 ap_rep.length = 0;
556 if (ret) {
557 goto reply;
559 talloc_free(tmp_ctx);
560 return ret;
563 /* Extract the data from the KRB-PRIV half of the message */
564 nt_status = gensec_unwrap(gensec_security, tmp_ctx, &krb_priv_req, &kpasswd_req);
565 if (!NT_STATUS_IS_OK(nt_status)) {
566 ret = kpasswdd_make_unauth_error_reply(kdc, mem_ctx,
567 KRB5_KPASSWD_HARDERROR,
568 talloc_asprintf(mem_ctx,
569 "gensec_unwrap failed: %s",
570 nt_errstr(nt_status)),
571 &krb_priv_rep);
572 ap_rep.length = 0;
573 if (ret) {
574 goto reply;
576 talloc_free(tmp_ctx);
577 return ret;
580 /* Figure out something to do with it (probably changing a password...) */
581 ret = kpasswd_process_request(kdc, tmp_ctx,
582 gensec_security,
583 version,
584 &kpasswd_req, &kpasswd_rep);
585 if (!ret) {
586 /* Argh! */
587 return false;
590 /* And wrap up the reply: This ensures that the error message
591 * or success can be verified by the client */
592 nt_status = gensec_wrap(gensec_security, tmp_ctx,
593 &kpasswd_rep, &krb_priv_rep);
594 if (!NT_STATUS_IS_OK(nt_status)) {
595 ret = kpasswdd_make_unauth_error_reply(kdc, mem_ctx,
596 KRB5_KPASSWD_HARDERROR,
597 talloc_asprintf(mem_ctx,
598 "gensec_wrap failed: %s",
599 nt_errstr(nt_status)),
600 &krb_priv_rep);
601 ap_rep.length = 0;
602 if (ret) {
603 goto reply;
605 talloc_free(tmp_ctx);
606 return ret;
609 reply:
610 *reply = data_blob_talloc(mem_ctx, NULL, krb_priv_rep.length + ap_rep.length + header_len);
611 if (!reply->data) {
612 return false;
615 RSSVAL(reply->data, 0, reply->length);
616 RSSVAL(reply->data, 2, 1); /* This is a version 1 reply, MS change/set or otherwise */
617 RSSVAL(reply->data, 4, ap_rep.length);
618 memcpy(reply->data + header_len,
619 ap_rep.data,
620 ap_rep.length);
621 memcpy(reply->data + header_len + ap_rep.length,
622 krb_priv_rep.data,
623 krb_priv_rep.length);
625 talloc_free(tmp_ctx);
626 return ret;