r25068: Older samba3 DCs will return DCERPC_FAULT_OP_RNG_ERROR for every opcode on the
[Samba.git] / source / smbd / seal.c
blob5d8ef9b63c8a35e6754cd761530b01617ce5c266
1 /*
2 Unix SMB/CIFS implementation.
3 SMB Transport encryption (sealing) code - server code.
4 Copyright (C) Jeremy Allison 2007.
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, write to the Free Software
18 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
21 #include "includes.h"
23 /******************************************************************************
24 Server side encryption.
25 ******************************************************************************/
27 /******************************************************************************
28 Global server state.
29 ******************************************************************************/
31 struct smb_srv_trans_enc_ctx {
32 struct smb_trans_enc_state *es;
33 AUTH_NTLMSSP_STATE *auth_ntlmssp_state; /* Must be kept in sync with pointer in ec->ntlmssp_state. */
36 static struct smb_srv_trans_enc_ctx *partial_srv_trans_enc_ctx;
37 static struct smb_srv_trans_enc_ctx *srv_trans_enc_ctx;
39 /******************************************************************************
40 Is server encryption on ?
41 ******************************************************************************/
43 BOOL srv_encryption_on(void)
45 if (srv_trans_enc_ctx) {
46 return common_encryption_on(srv_trans_enc_ctx->es);
48 return False;
51 /******************************************************************************
52 Create an auth_ntlmssp_state and ensure pointer copy is correct.
53 ******************************************************************************/
55 static NTSTATUS make_auth_ntlmssp(struct smb_srv_trans_enc_ctx *ec)
57 NTSTATUS status = auth_ntlmssp_start(&ec->auth_ntlmssp_state);
58 if (!NT_STATUS_IS_OK(status)) {
59 return nt_status_squash(status);
63 * We must remember to update the pointer copy for the common
64 * functions after any auth_ntlmssp_start/auth_ntlmssp_end.
66 ec->es->s.ntlmssp_state = ec->auth_ntlmssp_state->ntlmssp_state;
67 return status;
70 /******************************************************************************
71 Destroy an auth_ntlmssp_state and ensure pointer copy is correct.
72 ******************************************************************************/
74 static void destroy_auth_ntlmssp(struct smb_srv_trans_enc_ctx *ec)
77 * We must remember to update the pointer copy for the common
78 * functions after any auth_ntlmssp_start/auth_ntlmssp_end.
81 if (ec->auth_ntlmssp_state) {
82 auth_ntlmssp_end(&ec->auth_ntlmssp_state);
83 /* The auth_ntlmssp_end killed this already. */
84 ec->es->s.ntlmssp_state = NULL;
88 #if defined(HAVE_GSSAPI) && defined(HAVE_KRB5)
90 /******************************************************************************
91 Import a name.
92 ******************************************************************************/
94 static NTSTATUS get_srv_gss_creds(const char *service,
95 const char *name,
96 gss_cred_usage_t cred_type,
97 gss_cred_id_t *p_srv_cred)
99 OM_uint32 ret;
100 OM_uint32 min;
101 gss_name_t srv_name;
102 gss_buffer_desc input_name;
103 char *host_princ_s = NULL;
104 NTSTATUS status = NT_STATUS_OK;
106 gss_OID_desc nt_hostbased_service =
107 {10, CONST_DISCARD(char *,"\x2a\x86\x48\x86\xf7\x12\x01\x02\x01\x04")};
109 asprintf(&host_princ_s, "%s@%s", service, name);
110 if (host_princ_s == NULL) {
111 return NT_STATUS_NO_MEMORY;
114 input_name.value = host_princ_s;
115 input_name.length = strlen(host_princ_s) + 1;
117 ret = gss_import_name(&min,
118 &input_name,
119 &nt_hostbased_service,
120 &srv_name);
122 DEBUG(10,("get_srv_gss_creds: imported name %s\n",
123 host_princ_s ));
125 if (ret != GSS_S_COMPLETE) {
126 SAFE_FREE(host_princ_s);
127 return map_nt_error_from_gss(ret, min);
131 * We're accessing the krb5.keytab file here.
132 * ensure we have permissions to do so.
134 become_root();
136 ret = gss_acquire_cred(&min,
137 srv_name,
138 GSS_C_INDEFINITE,
139 GSS_C_NULL_OID_SET,
140 cred_type,
141 p_srv_cred,
142 NULL,
143 NULL);
144 unbecome_root();
146 if (ret != GSS_S_COMPLETE) {
147 ADS_STATUS adss = ADS_ERROR_GSS(ret, min);
148 DEBUG(10,("get_srv_gss_creds: gss_acquire_cred failed with %s\n",
149 ads_errstr(adss)));
150 status = map_nt_error_from_gss(ret, min);
153 SAFE_FREE(host_princ_s);
154 gss_release_name(&min, &srv_name);
155 return status;
158 /******************************************************************************
159 Create a gss state.
160 Try and get the cifs/server@realm principal first, then fall back to
161 host/server@realm.
162 ******************************************************************************/
164 static NTSTATUS make_auth_gss(struct smb_srv_trans_enc_ctx *ec)
166 NTSTATUS status;
167 gss_cred_id_t srv_cred;
168 fstring fqdn;
170 name_to_fqdn(fqdn, global_myname());
171 strlower_m(fqdn);
173 status = get_srv_gss_creds("cifs", fqdn, GSS_C_ACCEPT, &srv_cred);
174 if (!NT_STATUS_IS_OK(status)) {
175 status = get_srv_gss_creds("host", fqdn, GSS_C_ACCEPT, &srv_cred);
176 if (!NT_STATUS_IS_OK(status)) {
177 return nt_status_squash(status);
181 ec->es->s.gss_state = SMB_MALLOC_P(struct smb_tran_enc_state_gss);
182 if (!ec->es->s.gss_state) {
183 OM_uint32 min;
184 gss_release_cred(&min, &srv_cred);
185 return NT_STATUS_NO_MEMORY;
187 ZERO_STRUCTP(ec->es->s.gss_state);
188 ec->es->s.gss_state->creds = srv_cred;
190 /* No context yet. */
191 ec->es->s.gss_state->gss_ctx = GSS_C_NO_CONTEXT;
193 return NT_STATUS_OK;
195 #endif
197 /******************************************************************************
198 Shutdown a server encryption context.
199 ******************************************************************************/
201 static void srv_free_encryption_context(struct smb_srv_trans_enc_ctx **pp_ec)
203 struct smb_srv_trans_enc_ctx *ec = *pp_ec;
205 if (!ec) {
206 return;
209 if (ec->es) {
210 switch (ec->es->smb_enc_type) {
211 case SMB_TRANS_ENC_NTLM:
212 destroy_auth_ntlmssp(ec);
213 break;
214 #if defined(HAVE_GSSAPI) && defined(HAVE_KRB5)
215 case SMB_TRANS_ENC_GSS:
216 break;
217 #endif
219 common_free_encryption_state(&ec->es);
222 SAFE_FREE(ec);
223 *pp_ec = NULL;
226 /******************************************************************************
227 Create a server encryption context.
228 ******************************************************************************/
230 static NTSTATUS make_srv_encryption_context(enum smb_trans_enc_type smb_enc_type, struct smb_srv_trans_enc_ctx **pp_ec)
232 struct smb_srv_trans_enc_ctx *ec;
234 *pp_ec = NULL;
236 ec = SMB_MALLOC_P(struct smb_srv_trans_enc_ctx);
237 if (!ec) {
238 return NT_STATUS_NO_MEMORY;
240 ZERO_STRUCTP(partial_srv_trans_enc_ctx);
241 ec->es = SMB_MALLOC_P(struct smb_trans_enc_state);
242 if (!ec->es) {
243 SAFE_FREE(ec);
244 return NT_STATUS_NO_MEMORY;
246 ZERO_STRUCTP(ec->es);
247 ec->es->smb_enc_type = smb_enc_type;
248 switch (smb_enc_type) {
249 case SMB_TRANS_ENC_NTLM:
251 NTSTATUS status = make_auth_ntlmssp(ec);
252 if (!NT_STATUS_IS_OK(status)) {
253 srv_free_encryption_context(&ec);
254 return status;
257 break;
259 #if defined(HAVE_GSSAPI) && defined(HAVE_KRB5)
260 case SMB_TRANS_ENC_GSS:
261 /* Acquire our credentials by calling gss_acquire_cred here. */
263 NTSTATUS status = make_auth_gss(ec);
264 if (!NT_STATUS_IS_OK(status)) {
265 srv_free_encryption_context(&ec);
266 return status;
269 break;
270 #endif
271 default:
272 srv_free_encryption_context(&ec);
273 return NT_STATUS_INVALID_PARAMETER;
275 *pp_ec = ec;
276 return NT_STATUS_OK;
279 /******************************************************************************
280 Free an encryption-allocated buffer.
281 ******************************************************************************/
283 void srv_free_enc_buffer(char *buf)
285 /* We know this is an smb buffer, and we
286 * didn't malloc, only copy, for a keepalive,
287 * so ignore session keepalives. */
289 if(CVAL(buf,0) == SMBkeepalive) {
290 return;
293 if (srv_trans_enc_ctx) {
294 common_free_enc_buffer(srv_trans_enc_ctx->es, buf);
298 /******************************************************************************
299 Decrypt an incoming buffer.
300 ******************************************************************************/
302 NTSTATUS srv_decrypt_buffer(char *buf)
304 /* Ignore session keepalives. */
305 if(CVAL(buf,0) == SMBkeepalive) {
306 return NT_STATUS_OK;
309 if (srv_trans_enc_ctx) {
310 return common_decrypt_buffer(srv_trans_enc_ctx->es, buf);
313 return NT_STATUS_OK;
316 /******************************************************************************
317 Encrypt an outgoing buffer. Return the encrypted pointer in buf_out.
318 ******************************************************************************/
320 NTSTATUS srv_encrypt_buffer(char *buf, char **buf_out)
322 *buf_out = buf;
324 /* Ignore session keepalives. */
325 if(CVAL(buf,0) == SMBkeepalive) {
326 return NT_STATUS_OK;
329 if (srv_trans_enc_ctx) {
330 return common_encrypt_buffer(srv_trans_enc_ctx->es, buf, buf_out);
332 /* Not encrypting. */
333 return NT_STATUS_OK;
336 /******************************************************************************
337 Do the gss encryption negotiation. Parameters are in/out.
338 Until success we do everything on the partial enc ctx.
339 ******************************************************************************/
341 #if defined(HAVE_GSSAPI) && defined(HAVE_KRB5)
342 static NTSTATUS srv_enc_spnego_gss_negotiate(unsigned char **ppdata, size_t *p_data_size, DATA_BLOB secblob)
344 OM_uint32 ret;
345 OM_uint32 min;
346 OM_uint32 flags = 0;
347 gss_buffer_desc in_buf, out_buf;
348 struct smb_tran_enc_state_gss *gss_state;
349 DATA_BLOB auth_reply = data_blob_null;
350 DATA_BLOB response = data_blob_null;
351 NTSTATUS status;
353 if (!partial_srv_trans_enc_ctx) {
354 status = make_srv_encryption_context(SMB_TRANS_ENC_GSS, &partial_srv_trans_enc_ctx);
355 if (!NT_STATUS_IS_OK(status)) {
356 return status;
360 gss_state = partial_srv_trans_enc_ctx->es->s.gss_state;
362 in_buf.value = secblob.data;
363 in_buf.length = secblob.length;
365 out_buf.value = NULL;
366 out_buf.length = 0;
368 become_root();
370 ret = gss_accept_sec_context(&min,
371 &gss_state->gss_ctx,
372 gss_state->creds,
373 &in_buf,
374 GSS_C_NO_CHANNEL_BINDINGS,
375 NULL,
376 NULL, /* Ignore oids. */
377 &out_buf, /* To return. */
378 &flags,
379 NULL, /* Ingore time. */
380 NULL); /* Ignore delegated creds. */
381 unbecome_root();
383 status = gss_err_to_ntstatus(ret, min);
384 if (ret != GSS_S_COMPLETE && ret != GSS_S_CONTINUE_NEEDED) {
385 return status;
388 /* Ensure we've got sign+seal available. */
389 if (ret == GSS_S_COMPLETE) {
390 if ((flags & (GSS_C_INTEG_FLAG|GSS_C_CONF_FLAG|GSS_C_REPLAY_FLAG|GSS_C_SEQUENCE_FLAG)) !=
391 (GSS_C_INTEG_FLAG|GSS_C_CONF_FLAG|GSS_C_REPLAY_FLAG|GSS_C_SEQUENCE_FLAG)) {
392 DEBUG(0,("srv_enc_spnego_gss_negotiate: quality of service not good enough "
393 "for SMB sealing.\n"));
394 gss_release_buffer(&min, &out_buf);
395 return NT_STATUS_ACCESS_DENIED;
399 auth_reply = data_blob(out_buf.value, out_buf.length);
400 gss_release_buffer(&min, &out_buf);
402 /* Wrap in SPNEGO. */
403 response = spnego_gen_auth_response(&auth_reply, status, OID_KERBEROS5);
404 data_blob_free(&auth_reply);
406 SAFE_FREE(*ppdata);
407 *ppdata = response.data;
408 *p_data_size = response.length;
410 return status;
412 #endif
414 /******************************************************************************
415 Do the NTLM SPNEGO (or raw) encryption negotiation. Parameters are in/out.
416 Until success we do everything on the partial enc ctx.
417 ******************************************************************************/
419 static NTSTATUS srv_enc_ntlm_negotiate(unsigned char **ppdata, size_t *p_data_size, DATA_BLOB secblob, BOOL spnego_wrap)
421 NTSTATUS status;
422 DATA_BLOB chal = data_blob_null;
423 DATA_BLOB response = data_blob_null;
425 status = make_srv_encryption_context(SMB_TRANS_ENC_NTLM, &partial_srv_trans_enc_ctx);
426 if (!NT_STATUS_IS_OK(status)) {
427 return status;
430 status = auth_ntlmssp_update(partial_srv_trans_enc_ctx->auth_ntlmssp_state, secblob, &chal);
432 /* status here should be NT_STATUS_MORE_PROCESSING_REQUIRED
433 * for success ... */
435 if (spnego_wrap) {
436 response = spnego_gen_auth_response(&chal, status, OID_NTLMSSP);
437 data_blob_free(&chal);
438 } else {
439 /* Return the raw blob. */
440 response = chal;
443 SAFE_FREE(*ppdata);
444 *ppdata = response.data;
445 *p_data_size = response.length;
446 return status;
449 /******************************************************************************
450 Do the SPNEGO encryption negotiation. Parameters are in/out.
451 Based off code in smbd/sesssionsetup.c
452 Until success we do everything on the partial enc ctx.
453 ******************************************************************************/
455 static NTSTATUS srv_enc_spnego_negotiate(connection_struct *conn,
456 unsigned char **ppdata,
457 size_t *p_data_size,
458 unsigned char **pparam,
459 size_t *p_param_size)
461 NTSTATUS status;
462 DATA_BLOB blob = data_blob_null;
463 DATA_BLOB secblob = data_blob_null;
464 BOOL got_kerberos_mechanism = False;
466 blob = data_blob_const(*ppdata, *p_data_size);
468 status = parse_spnego_mechanisms(blob, &secblob, &got_kerberos_mechanism);
469 if (!NT_STATUS_IS_OK(status)) {
470 return nt_status_squash(status);
473 /* We should have no partial context at this point. */
475 srv_free_encryption_context(&partial_srv_trans_enc_ctx);
477 #if defined(HAVE_GSSAPI) && defined(HAVE_KRB5)
478 if (got_kerberos_mechanism && lp_use_kerberos_keytab() ) {
479 status = srv_enc_spnego_gss_negotiate(ppdata, p_data_size, secblob);
480 } else
481 #endif
483 status = srv_enc_ntlm_negotiate(ppdata, p_data_size, secblob, True);
486 data_blob_free(&secblob);
488 if (!NT_STATUS_EQUAL(status,NT_STATUS_MORE_PROCESSING_REQUIRED) && !NT_STATUS_IS_OK(status)) {
489 srv_free_encryption_context(&partial_srv_trans_enc_ctx);
490 return nt_status_squash(status);
493 if (NT_STATUS_IS_OK(status)) {
494 /* Return the context we're using for this encryption state. */
495 if (!(*pparam = SMB_MALLOC_ARRAY(unsigned char, 2))) {
496 return NT_STATUS_NO_MEMORY;
498 SSVAL(*pparam,0,partial_srv_trans_enc_ctx->es->enc_ctx_num);
499 *p_param_size = 2;
502 return status;
505 /******************************************************************************
506 Complete a SPNEGO encryption negotiation. Parameters are in/out.
507 We only get this for a NTLM auth second stage.
508 ******************************************************************************/
510 static NTSTATUS srv_enc_spnego_ntlm_auth(connection_struct *conn,
511 unsigned char **ppdata,
512 size_t *p_data_size,
513 unsigned char **pparam,
514 size_t *p_param_size)
516 NTSTATUS status;
517 DATA_BLOB blob = data_blob_null;
518 DATA_BLOB auth = data_blob_null;
519 DATA_BLOB auth_reply = data_blob_null;
520 DATA_BLOB response = data_blob_null;
521 struct smb_srv_trans_enc_ctx *ec = partial_srv_trans_enc_ctx;
523 /* We must have a partial context here. */
525 if (!ec || !ec->es || ec->auth_ntlmssp_state == NULL || ec->es->smb_enc_type != SMB_TRANS_ENC_NTLM) {
526 srv_free_encryption_context(&partial_srv_trans_enc_ctx);
527 return NT_STATUS_INVALID_PARAMETER;
530 blob = data_blob_const(*ppdata, *p_data_size);
531 if (!spnego_parse_auth(blob, &auth)) {
532 srv_free_encryption_context(&partial_srv_trans_enc_ctx);
533 return NT_STATUS_INVALID_PARAMETER;
536 status = auth_ntlmssp_update(ec->auth_ntlmssp_state, auth, &auth_reply);
537 data_blob_free(&auth);
539 response = spnego_gen_auth_response(&auth_reply, status, OID_NTLMSSP);
540 data_blob_free(&auth_reply);
542 if (NT_STATUS_IS_OK(status)) {
543 /* Return the context we're using for this encryption state. */
544 if (!(*pparam = SMB_MALLOC_ARRAY(unsigned char, 2))) {
545 return NT_STATUS_NO_MEMORY;
547 SSVAL(*pparam,0,ec->es->enc_ctx_num);
548 *p_param_size = 2;
551 SAFE_FREE(*ppdata);
552 *ppdata = response.data;
553 *p_data_size = response.length;
554 return status;
557 /******************************************************************************
558 Raw NTLM encryption negotiation. Parameters are in/out.
559 This function does both steps.
560 ******************************************************************************/
562 static NTSTATUS srv_enc_raw_ntlm_auth(connection_struct *conn,
563 unsigned char **ppdata,
564 size_t *p_data_size,
565 unsigned char **pparam,
566 size_t *p_param_size)
568 NTSTATUS status;
569 DATA_BLOB blob = data_blob_const(*ppdata, *p_data_size);
570 DATA_BLOB response = data_blob_null;
571 struct smb_srv_trans_enc_ctx *ec;
573 if (!partial_srv_trans_enc_ctx) {
574 /* This is the initial step. */
575 status = srv_enc_ntlm_negotiate(ppdata, p_data_size, blob, False);
576 if (!NT_STATUS_EQUAL(status,NT_STATUS_MORE_PROCESSING_REQUIRED) && !NT_STATUS_IS_OK(status)) {
577 srv_free_encryption_context(&partial_srv_trans_enc_ctx);
578 return nt_status_squash(status);
580 return status;
583 ec = partial_srv_trans_enc_ctx;
584 if (!ec || !ec->es || ec->auth_ntlmssp_state == NULL || ec->es->smb_enc_type != SMB_TRANS_ENC_NTLM) {
585 srv_free_encryption_context(&partial_srv_trans_enc_ctx);
586 return NT_STATUS_INVALID_PARAMETER;
589 /* Second step. */
590 status = auth_ntlmssp_update(partial_srv_trans_enc_ctx->auth_ntlmssp_state, blob, &response);
592 if (NT_STATUS_IS_OK(status)) {
593 /* Return the context we're using for this encryption state. */
594 if (!(*pparam = SMB_MALLOC_ARRAY(unsigned char, 2))) {
595 return NT_STATUS_NO_MEMORY;
597 SSVAL(*pparam,0,ec->es->enc_ctx_num);
598 *p_param_size = 2;
601 /* Return the raw blob. */
602 SAFE_FREE(*ppdata);
603 *ppdata = response.data;
604 *p_data_size = response.length;
605 return status;
608 /******************************************************************************
609 Do the SPNEGO encryption negotiation. Parameters are in/out.
610 ******************************************************************************/
612 NTSTATUS srv_request_encryption_setup(connection_struct *conn,
613 unsigned char **ppdata,
614 size_t *p_data_size,
615 unsigned char **pparam,
616 size_t *p_param_size)
618 unsigned char *pdata = *ppdata;
620 SAFE_FREE(*pparam);
621 *p_param_size = 0;
623 if (*p_data_size < 1) {
624 return NT_STATUS_INVALID_PARAMETER;
627 if (pdata[0] == ASN1_APPLICATION(0)) {
628 /* its a negTokenTarg packet */
629 return srv_enc_spnego_negotiate(conn, ppdata, p_data_size, pparam, p_param_size);
632 if (pdata[0] == ASN1_CONTEXT(1)) {
633 /* It's an auth packet */
634 return srv_enc_spnego_ntlm_auth(conn, ppdata, p_data_size, pparam, p_param_size);
637 /* Maybe it's a raw unwrapped auth ? */
638 if (*p_data_size < 7) {
639 return NT_STATUS_INVALID_PARAMETER;
642 if (strncmp((char *)pdata, "NTLMSSP", 7) == 0) {
643 return srv_enc_raw_ntlm_auth(conn, ppdata, p_data_size, pparam, p_param_size);
646 DEBUG(1,("srv_request_encryption_setup: Unknown packet\n"));
648 return NT_STATUS_LOGON_FAILURE;
651 /******************************************************************************
652 Negotiation was successful - turn on server-side encryption.
653 ******************************************************************************/
655 static NTSTATUS check_enc_good(struct smb_srv_trans_enc_ctx *ec)
657 if (!ec || !ec->es) {
658 return NT_STATUS_LOGON_FAILURE;
661 if (ec->es->smb_enc_type == SMB_TRANS_ENC_NTLM) {
662 if ((ec->es->s.ntlmssp_state->neg_flags & (NTLMSSP_NEGOTIATE_SIGN|NTLMSSP_NEGOTIATE_SEAL)) !=
663 (NTLMSSP_NEGOTIATE_SIGN|NTLMSSP_NEGOTIATE_SEAL)) {
664 return NT_STATUS_INVALID_PARAMETER;
667 /* Todo - check gssapi case. */
669 return NT_STATUS_OK;
672 /******************************************************************************
673 Negotiation was successful - turn on server-side encryption.
674 ******************************************************************************/
676 NTSTATUS srv_encryption_start(connection_struct *conn)
678 NTSTATUS status;
680 /* Check that we are really doing sign+seal. */
681 status = check_enc_good(partial_srv_trans_enc_ctx);
682 if (!NT_STATUS_IS_OK(status)) {
683 return status;
685 /* Throw away the context we're using currently (if any). */
686 srv_free_encryption_context(&srv_trans_enc_ctx);
688 /* Steal the partial pointer. Deliberate shallow copy. */
689 srv_trans_enc_ctx = partial_srv_trans_enc_ctx;
690 srv_trans_enc_ctx->es->enc_on = True;
692 partial_srv_trans_enc_ctx = NULL;
693 return NT_STATUS_OK;
696 /******************************************************************************
697 Shutdown all server contexts.
698 ******************************************************************************/
700 void server_encryption_shutdown(void)
702 srv_free_encryption_context(&partial_srv_trans_enc_ctx);
703 srv_free_encryption_context(&srv_trans_enc_ctx);