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 3 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, see <http://www.gnu.org/licenses/>.
21 #include "smbd/smbd.h"
22 #include "smbd/globals.h"
23 #include "../libcli/auth/spnego.h"
24 #include "../libcli/auth/ntlmssp.h"
25 #include "ntlmssp_wrap.h"
26 #include "smb_crypt.h"
27 #include "../lib/util/asn1.h"
30 /******************************************************************************
31 Server side encryption.
32 ******************************************************************************/
34 /******************************************************************************
36 ******************************************************************************/
38 struct smb_srv_trans_enc_ctx
{
39 struct smb_trans_enc_state
*es
;
40 struct auth_ntlmssp_state
*auth_ntlmssp_state
; /* Must be kept in sync with pointer in ec->ntlmssp_state. */
43 /******************************************************************************
44 Return global enc context - this must change if we ever do multiple contexts.
45 ******************************************************************************/
47 uint16_t srv_enc_ctx(void)
49 return srv_trans_enc_ctx
->es
->enc_ctx_num
;
52 /******************************************************************************
53 Is this an incoming encrypted packet ?
54 ******************************************************************************/
56 bool is_encrypted_packet(const uint8_t *inbuf
)
61 /* Ignore non-session messages or non 0xFF'E' messages. */
63 || (smb_len(inbuf
) < 8)
64 || !(inbuf
[4] == 0xFF && inbuf
[5] == 'E')) {
68 status
= get_enc_ctx_num(inbuf
, &enc_num
);
69 if (!NT_STATUS_IS_OK(status
)) {
73 /* Encrypted messages are 0xFF'E'<ctx> */
74 if (srv_trans_enc_ctx
&& enc_num
== srv_enc_ctx()) {
80 /******************************************************************************
81 Create an auth_ntlmssp_state and ensure pointer copy is correct.
82 ******************************************************************************/
84 static NTSTATUS
make_auth_ntlmssp(struct smb_srv_trans_enc_ctx
*ec
)
86 NTSTATUS status
= auth_ntlmssp_start(&ec
->auth_ntlmssp_state
);
87 if (!NT_STATUS_IS_OK(status
)) {
88 return nt_status_squash(status
);
92 * We must remember to update the pointer copy for the common
93 * functions after any auth_ntlmssp_start/auth_ntlmssp_end.
95 ec
->es
->s
.ntlmssp_state
= auth_ntlmssp_get_ntlmssp_state(ec
->auth_ntlmssp_state
);
99 /******************************************************************************
100 Destroy an auth_ntlmssp_state and ensure pointer copy is correct.
101 ******************************************************************************/
103 static void destroy_auth_ntlmssp(struct smb_srv_trans_enc_ctx
*ec
)
106 * We must remember to update the pointer copy for the common
107 * functions after any auth_ntlmssp_start/auth_ntlmssp_end.
110 if (ec
->auth_ntlmssp_state
) {
111 TALLOC_FREE(ec
->auth_ntlmssp_state
);
112 /* The auth_ntlmssp_end killed this already. */
113 ec
->es
->s
.ntlmssp_state
= NULL
;
117 #if defined(HAVE_GSSAPI) && defined(HAVE_KRB5)
119 /******************************************************************************
121 ******************************************************************************/
123 static NTSTATUS
get_srv_gss_creds(const char *service
,
125 gss_cred_usage_t cred_type
,
126 gss_cred_id_t
*p_srv_cred
)
131 gss_buffer_desc input_name
;
132 char *host_princ_s
= NULL
;
133 NTSTATUS status
= NT_STATUS_OK
;
135 gss_OID_desc nt_hostbased_service
=
136 {10, CONST_DISCARD(char *,"\x2a\x86\x48\x86\xf7\x12\x01\x02\x01\x04")};
138 if (asprintf(&host_princ_s
, "%s@%s", service
, name
) == -1) {
139 return NT_STATUS_NO_MEMORY
;
142 input_name
.value
= host_princ_s
;
143 input_name
.length
= strlen(host_princ_s
) + 1;
145 ret
= gss_import_name(&min
,
147 &nt_hostbased_service
,
150 DEBUG(10,("get_srv_gss_creds: imported name %s\n",
153 if (ret
!= GSS_S_COMPLETE
) {
154 SAFE_FREE(host_princ_s
);
155 return map_nt_error_from_gss(ret
, min
);
159 * We're accessing the krb5.keytab file here.
160 * ensure we have permissions to do so.
164 ret
= gss_acquire_cred(&min
,
174 if (ret
!= GSS_S_COMPLETE
) {
175 ADS_STATUS adss
= ADS_ERROR_GSS(ret
, min
);
176 DEBUG(10,("get_srv_gss_creds: gss_acquire_cred failed with %s\n",
178 status
= map_nt_error_from_gss(ret
, min
);
181 SAFE_FREE(host_princ_s
);
182 gss_release_name(&min
, &srv_name
);
186 /******************************************************************************
188 Try and get the cifs/server@realm principal first, then fall back to
190 ******************************************************************************/
192 static NTSTATUS
make_auth_gss(struct smb_srv_trans_enc_ctx
*ec
)
195 gss_cred_id_t srv_cred
;
198 name_to_fqdn(fqdn
, global_myname());
201 status
= get_srv_gss_creds("cifs", fqdn
, GSS_C_ACCEPT
, &srv_cred
);
202 if (!NT_STATUS_IS_OK(status
)) {
203 status
= get_srv_gss_creds("host", fqdn
, GSS_C_ACCEPT
, &srv_cred
);
204 if (!NT_STATUS_IS_OK(status
)) {
205 return nt_status_squash(status
);
209 ec
->es
->s
.gss_state
= SMB_MALLOC_P(struct smb_tran_enc_state_gss
);
210 if (!ec
->es
->s
.gss_state
) {
212 gss_release_cred(&min
, &srv_cred
);
213 return NT_STATUS_NO_MEMORY
;
215 ZERO_STRUCTP(ec
->es
->s
.gss_state
);
216 ec
->es
->s
.gss_state
->creds
= srv_cred
;
218 /* No context yet. */
219 ec
->es
->s
.gss_state
->gss_ctx
= GSS_C_NO_CONTEXT
;
225 /******************************************************************************
226 Shutdown a server encryption context.
227 ******************************************************************************/
229 static void srv_free_encryption_context(struct smb_srv_trans_enc_ctx
**pp_ec
)
231 struct smb_srv_trans_enc_ctx
*ec
= *pp_ec
;
238 switch (ec
->es
->smb_enc_type
) {
239 case SMB_TRANS_ENC_NTLM
:
240 destroy_auth_ntlmssp(ec
);
242 #if defined(HAVE_GSSAPI) && defined(HAVE_KRB5)
243 case SMB_TRANS_ENC_GSS
:
247 common_free_encryption_state(&ec
->es
);
254 /******************************************************************************
255 Create a server encryption context.
256 ******************************************************************************/
258 static NTSTATUS
make_srv_encryption_context(enum smb_trans_enc_type smb_enc_type
, struct smb_srv_trans_enc_ctx
**pp_ec
)
260 struct smb_srv_trans_enc_ctx
*ec
;
264 ec
= SMB_MALLOC_P(struct smb_srv_trans_enc_ctx
);
266 return NT_STATUS_NO_MEMORY
;
268 ZERO_STRUCTP(partial_srv_trans_enc_ctx
);
269 ec
->es
= SMB_MALLOC_P(struct smb_trans_enc_state
);
272 return NT_STATUS_NO_MEMORY
;
274 ZERO_STRUCTP(ec
->es
);
275 ec
->es
->smb_enc_type
= smb_enc_type
;
276 switch (smb_enc_type
) {
277 case SMB_TRANS_ENC_NTLM
:
279 NTSTATUS status
= make_auth_ntlmssp(ec
);
280 if (!NT_STATUS_IS_OK(status
)) {
281 srv_free_encryption_context(&ec
);
287 #if defined(HAVE_GSSAPI) && defined(HAVE_KRB5)
288 case SMB_TRANS_ENC_GSS
:
289 /* Acquire our credentials by calling gss_acquire_cred here. */
291 NTSTATUS status
= make_auth_gss(ec
);
292 if (!NT_STATUS_IS_OK(status
)) {
293 srv_free_encryption_context(&ec
);
300 srv_free_encryption_context(&ec
);
301 return NT_STATUS_INVALID_PARAMETER
;
307 /******************************************************************************
308 Free an encryption-allocated buffer.
309 ******************************************************************************/
311 void srv_free_enc_buffer(char *buf
)
313 /* We know this is an smb buffer, and we
314 * didn't malloc, only copy, for a keepalive,
315 * so ignore non-session messages. */
321 if (srv_trans_enc_ctx
) {
322 common_free_enc_buffer(srv_trans_enc_ctx
->es
, buf
);
326 /******************************************************************************
327 Decrypt an incoming buffer.
328 ******************************************************************************/
330 NTSTATUS
srv_decrypt_buffer(char *buf
)
332 /* Ignore non-session messages. */
337 if (srv_trans_enc_ctx
) {
338 return common_decrypt_buffer(srv_trans_enc_ctx
->es
, buf
);
344 /******************************************************************************
345 Encrypt an outgoing buffer. Return the encrypted pointer in buf_out.
346 ******************************************************************************/
348 NTSTATUS
srv_encrypt_buffer(char *buf
, char **buf_out
)
352 /* Ignore non-session messages. */
357 if (srv_trans_enc_ctx
) {
358 return common_encrypt_buffer(srv_trans_enc_ctx
->es
, buf
, buf_out
);
360 /* Not encrypting. */
364 /******************************************************************************
365 Do the gss encryption negotiation. Parameters are in/out.
366 Until success we do everything on the partial enc ctx.
367 ******************************************************************************/
369 #if defined(HAVE_GSSAPI) && defined(HAVE_KRB5)
370 static NTSTATUS
srv_enc_spnego_gss_negotiate(unsigned char **ppdata
, size_t *p_data_size
, DATA_BLOB secblob
)
375 gss_buffer_desc in_buf
, out_buf
;
376 struct smb_tran_enc_state_gss
*gss_state
;
377 DATA_BLOB auth_reply
= data_blob_null
;
378 DATA_BLOB response
= data_blob_null
;
381 if (!partial_srv_trans_enc_ctx
) {
382 status
= make_srv_encryption_context(SMB_TRANS_ENC_GSS
, &partial_srv_trans_enc_ctx
);
383 if (!NT_STATUS_IS_OK(status
)) {
388 gss_state
= partial_srv_trans_enc_ctx
->es
->s
.gss_state
;
390 in_buf
.value
= secblob
.data
;
391 in_buf
.length
= secblob
.length
;
393 out_buf
.value
= NULL
;
398 ret
= gss_accept_sec_context(&min
,
402 GSS_C_NO_CHANNEL_BINDINGS
,
404 NULL
, /* Ignore oids. */
405 &out_buf
, /* To return. */
407 NULL
, /* Ingore time. */
408 NULL
); /* Ignore delegated creds. */
411 status
= gss_err_to_ntstatus(ret
, min
);
412 if (ret
!= GSS_S_COMPLETE
&& ret
!= GSS_S_CONTINUE_NEEDED
) {
416 /* Ensure we've got sign+seal available. */
417 if (ret
== GSS_S_COMPLETE
) {
418 if ((flags
& (GSS_C_INTEG_FLAG
|GSS_C_CONF_FLAG
|GSS_C_REPLAY_FLAG
|GSS_C_SEQUENCE_FLAG
)) !=
419 (GSS_C_INTEG_FLAG
|GSS_C_CONF_FLAG
|GSS_C_REPLAY_FLAG
|GSS_C_SEQUENCE_FLAG
)) {
420 DEBUG(0,("srv_enc_spnego_gss_negotiate: quality of service not good enough "
421 "for SMB sealing.\n"));
422 gss_release_buffer(&min
, &out_buf
);
423 return NT_STATUS_ACCESS_DENIED
;
427 auth_reply
= data_blob(out_buf
.value
, out_buf
.length
);
428 gss_release_buffer(&min
, &out_buf
);
430 /* Wrap in SPNEGO. */
431 response
= spnego_gen_auth_response(talloc_tos(), &auth_reply
, status
, OID_KERBEROS5
);
432 data_blob_free(&auth_reply
);
435 *ppdata
= (unsigned char *)memdup(response
.data
, response
.length
);
436 if ((*ppdata
) == NULL
&& response
.length
> 0) {
437 status
= NT_STATUS_NO_MEMORY
;
439 *p_data_size
= response
.length
;
441 data_blob_free(&response
);
447 /******************************************************************************
448 Do the NTLM SPNEGO (or raw) encryption negotiation. Parameters are in/out.
449 Until success we do everything on the partial enc ctx.
450 ******************************************************************************/
452 static NTSTATUS
srv_enc_ntlm_negotiate(unsigned char **ppdata
, size_t *p_data_size
, DATA_BLOB secblob
, bool spnego_wrap
)
455 DATA_BLOB chal
= data_blob_null
;
456 DATA_BLOB response
= data_blob_null
;
458 status
= make_srv_encryption_context(SMB_TRANS_ENC_NTLM
, &partial_srv_trans_enc_ctx
);
459 if (!NT_STATUS_IS_OK(status
)) {
463 status
= auth_ntlmssp_update(partial_srv_trans_enc_ctx
->auth_ntlmssp_state
, secblob
, &chal
);
465 /* status here should be NT_STATUS_MORE_PROCESSING_REQUIRED
469 response
= spnego_gen_auth_response(talloc_tos(), &chal
, status
, OID_NTLMSSP
);
470 data_blob_free(&chal
);
472 /* Return the raw blob. */
477 *ppdata
= (unsigned char *)memdup(response
.data
, response
.length
);
478 if ((*ppdata
) == NULL
&& response
.length
> 0) {
479 status
= NT_STATUS_NO_MEMORY
;
481 *p_data_size
= response
.length
;
482 data_blob_free(&response
);
487 /******************************************************************************
488 Do the SPNEGO encryption negotiation. Parameters are in/out.
489 Based off code in smbd/sesssionsetup.c
490 Until success we do everything on the partial enc ctx.
491 ******************************************************************************/
493 static NTSTATUS
srv_enc_spnego_negotiate(connection_struct
*conn
,
494 unsigned char **ppdata
,
496 unsigned char **pparam
,
497 size_t *p_param_size
)
500 DATA_BLOB blob
= data_blob_null
;
501 DATA_BLOB secblob
= data_blob_null
;
502 char *kerb_mech
= NULL
;
504 blob
= data_blob_const(*ppdata
, *p_data_size
);
506 status
= parse_spnego_mechanisms(talloc_tos(), blob
, &secblob
, &kerb_mech
);
507 if (!NT_STATUS_IS_OK(status
)) {
508 return nt_status_squash(status
);
511 /* We should have no partial context at this point. */
513 srv_free_encryption_context(&partial_srv_trans_enc_ctx
);
516 TALLOC_FREE(kerb_mech
);
518 #if defined(HAVE_GSSAPI) && defined(HAVE_KRB5)
519 status
= srv_enc_spnego_gss_negotiate(ppdata
, p_data_size
, secblob
);
521 /* Currently we don't SPNEGO negotiate
522 * back to NTLMSSP as we do in sessionsetupX. We should... */
523 return NT_STATUS_LOGON_FAILURE
;
526 status
= srv_enc_ntlm_negotiate(ppdata
, p_data_size
, secblob
, true);
529 data_blob_free(&secblob
);
531 if (!NT_STATUS_EQUAL(status
,NT_STATUS_MORE_PROCESSING_REQUIRED
) && !NT_STATUS_IS_OK(status
)) {
532 srv_free_encryption_context(&partial_srv_trans_enc_ctx
);
533 return nt_status_squash(status
);
536 if (NT_STATUS_IS_OK(status
)) {
537 /* Return the context we're using for this encryption state. */
538 if (!(*pparam
= SMB_MALLOC_ARRAY(unsigned char, 2))) {
539 return NT_STATUS_NO_MEMORY
;
541 SSVAL(*pparam
,0,partial_srv_trans_enc_ctx
->es
->enc_ctx_num
);
548 /******************************************************************************
549 Complete a SPNEGO encryption negotiation. Parameters are in/out.
550 We only get this for a NTLM auth second stage.
551 ******************************************************************************/
553 static NTSTATUS
srv_enc_spnego_ntlm_auth(connection_struct
*conn
,
554 unsigned char **ppdata
,
556 unsigned char **pparam
,
557 size_t *p_param_size
)
560 DATA_BLOB blob
= data_blob_null
;
561 DATA_BLOB auth
= data_blob_null
;
562 DATA_BLOB auth_reply
= data_blob_null
;
563 DATA_BLOB response
= data_blob_null
;
564 struct smb_srv_trans_enc_ctx
*ec
= partial_srv_trans_enc_ctx
;
566 /* We must have a partial context here. */
568 if (!ec
|| !ec
->es
|| ec
->auth_ntlmssp_state
== NULL
|| ec
->es
->smb_enc_type
!= SMB_TRANS_ENC_NTLM
) {
569 srv_free_encryption_context(&partial_srv_trans_enc_ctx
);
570 return NT_STATUS_INVALID_PARAMETER
;
573 blob
= data_blob_const(*ppdata
, *p_data_size
);
574 if (!spnego_parse_auth(talloc_tos(), blob
, &auth
)) {
575 srv_free_encryption_context(&partial_srv_trans_enc_ctx
);
576 return NT_STATUS_INVALID_PARAMETER
;
579 status
= auth_ntlmssp_update(ec
->auth_ntlmssp_state
, auth
, &auth_reply
);
580 data_blob_free(&auth
);
586 * This field SHALL only be present in the first reply from the
588 * So set mechOID to NULL here.
591 response
= spnego_gen_auth_response(talloc_tos(), &auth_reply
, status
, NULL
);
592 data_blob_free(&auth_reply
);
594 if (NT_STATUS_IS_OK(status
)) {
595 /* Return the context we're using for this encryption state. */
596 if (!(*pparam
= SMB_MALLOC_ARRAY(unsigned char, 2))) {
597 return NT_STATUS_NO_MEMORY
;
599 SSVAL(*pparam
,0,ec
->es
->enc_ctx_num
);
604 *ppdata
= (unsigned char *)memdup(response
.data
, response
.length
);
605 if ((*ppdata
) == NULL
&& response
.length
> 0)
606 return NT_STATUS_NO_MEMORY
;
607 *p_data_size
= response
.length
;
608 data_blob_free(&response
);
612 /******************************************************************************
613 Raw NTLM encryption negotiation. Parameters are in/out.
614 This function does both steps.
615 ******************************************************************************/
617 static NTSTATUS
srv_enc_raw_ntlm_auth(connection_struct
*conn
,
618 unsigned char **ppdata
,
620 unsigned char **pparam
,
621 size_t *p_param_size
)
624 DATA_BLOB blob
= data_blob_const(*ppdata
, *p_data_size
);
625 DATA_BLOB response
= data_blob_null
;
626 struct smb_srv_trans_enc_ctx
*ec
;
628 if (!partial_srv_trans_enc_ctx
) {
629 /* This is the initial step. */
630 status
= srv_enc_ntlm_negotiate(ppdata
, p_data_size
, blob
, false);
631 if (!NT_STATUS_EQUAL(status
,NT_STATUS_MORE_PROCESSING_REQUIRED
) && !NT_STATUS_IS_OK(status
)) {
632 srv_free_encryption_context(&partial_srv_trans_enc_ctx
);
633 return nt_status_squash(status
);
638 ec
= partial_srv_trans_enc_ctx
;
639 if (!ec
|| !ec
->es
|| ec
->auth_ntlmssp_state
== NULL
|| ec
->es
->smb_enc_type
!= SMB_TRANS_ENC_NTLM
) {
640 srv_free_encryption_context(&partial_srv_trans_enc_ctx
);
641 return NT_STATUS_INVALID_PARAMETER
;
645 status
= auth_ntlmssp_update(partial_srv_trans_enc_ctx
->auth_ntlmssp_state
, blob
, &response
);
647 if (NT_STATUS_IS_OK(status
)) {
648 /* Return the context we're using for this encryption state. */
649 if (!(*pparam
= SMB_MALLOC_ARRAY(unsigned char, 2))) {
650 return NT_STATUS_NO_MEMORY
;
652 SSVAL(*pparam
,0,ec
->es
->enc_ctx_num
);
656 /* Return the raw blob. */
658 *ppdata
= (unsigned char *)memdup(response
.data
, response
.length
);
659 if ((*ppdata
) == NULL
&& response
.length
> 0)
660 return NT_STATUS_NO_MEMORY
;
661 *p_data_size
= response
.length
;
662 data_blob_free(&response
);
666 /******************************************************************************
667 Do the SPNEGO encryption negotiation. Parameters are in/out.
668 ******************************************************************************/
670 NTSTATUS
srv_request_encryption_setup(connection_struct
*conn
,
671 unsigned char **ppdata
,
673 unsigned char **pparam
,
674 size_t *p_param_size
)
676 unsigned char *pdata
= *ppdata
;
681 if (*p_data_size
< 1) {
682 return NT_STATUS_INVALID_PARAMETER
;
685 if (pdata
[0] == ASN1_APPLICATION(0)) {
686 /* its a negTokenTarg packet */
687 return srv_enc_spnego_negotiate(conn
, ppdata
, p_data_size
, pparam
, p_param_size
);
690 if (pdata
[0] == ASN1_CONTEXT(1)) {
691 /* It's an auth packet */
692 return srv_enc_spnego_ntlm_auth(conn
, ppdata
, p_data_size
, pparam
, p_param_size
);
695 /* Maybe it's a raw unwrapped auth ? */
696 if (*p_data_size
< 7) {
697 return NT_STATUS_INVALID_PARAMETER
;
700 if (strncmp((char *)pdata
, "NTLMSSP", 7) == 0) {
701 return srv_enc_raw_ntlm_auth(conn
, ppdata
, p_data_size
, pparam
, p_param_size
);
704 DEBUG(1,("srv_request_encryption_setup: Unknown packet\n"));
706 return NT_STATUS_LOGON_FAILURE
;
709 /******************************************************************************
710 Negotiation was successful - turn on server-side encryption.
711 ******************************************************************************/
713 static NTSTATUS
check_enc_good(struct smb_srv_trans_enc_ctx
*ec
)
715 if (!ec
|| !ec
->es
) {
716 return NT_STATUS_LOGON_FAILURE
;
719 if (ec
->es
->smb_enc_type
== SMB_TRANS_ENC_NTLM
) {
720 if (!auth_ntlmssp_negotiated_sign((ec
->auth_ntlmssp_state
))) {
721 return NT_STATUS_INVALID_PARAMETER
;
724 if (!auth_ntlmssp_negotiated_seal((ec
->auth_ntlmssp_state
))) {
725 return NT_STATUS_INVALID_PARAMETER
;
728 /* Todo - check gssapi case. */
733 /******************************************************************************
734 Negotiation was successful - turn on server-side encryption.
735 ******************************************************************************/
737 NTSTATUS
srv_encryption_start(connection_struct
*conn
)
741 /* Check that we are really doing sign+seal. */
742 status
= check_enc_good(partial_srv_trans_enc_ctx
);
743 if (!NT_STATUS_IS_OK(status
)) {
746 /* Throw away the context we're using currently (if any). */
747 srv_free_encryption_context(&srv_trans_enc_ctx
);
749 /* Steal the partial pointer. Deliberate shallow copy. */
750 srv_trans_enc_ctx
= partial_srv_trans_enc_ctx
;
751 srv_trans_enc_ctx
->es
->enc_on
= true;
753 partial_srv_trans_enc_ctx
= NULL
;
755 DEBUG(1,("srv_encryption_start: context negotiated\n"));
759 /******************************************************************************
760 Shutdown all server contexts.
761 ******************************************************************************/
763 void server_encryption_shutdown(void)
765 srv_free_encryption_context(&partial_srv_trans_enc_ctx
);
766 srv_free_encryption_context(&srv_trans_enc_ctx
);