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"
29 #include "libsmb/libsmb.h"
31 /******************************************************************************
32 Server side encryption.
33 ******************************************************************************/
35 /******************************************************************************
37 ******************************************************************************/
39 struct smb_srv_trans_enc_ctx
{
40 struct smb_trans_enc_state
*es
;
41 struct auth_ntlmssp_state
*auth_ntlmssp_state
; /* Must be kept in sync with pointer in ec->ntlmssp_state. */
44 /******************************************************************************
45 Return global enc context - this must change if we ever do multiple contexts.
46 ******************************************************************************/
48 uint16_t srv_enc_ctx(void)
50 return srv_trans_enc_ctx
->es
->enc_ctx_num
;
53 /******************************************************************************
54 Is this an incoming encrypted packet ?
55 ******************************************************************************/
57 bool is_encrypted_packet(const uint8_t *inbuf
)
62 /* Ignore non-session messages or non 0xFF'E' messages. */
64 || (smb_len(inbuf
) < 8)
65 || !(inbuf
[4] == 0xFF && inbuf
[5] == 'E')) {
69 status
= get_enc_ctx_num(inbuf
, &enc_num
);
70 if (!NT_STATUS_IS_OK(status
)) {
74 /* Encrypted messages are 0xFF'E'<ctx> */
75 if (srv_trans_enc_ctx
&& enc_num
== srv_enc_ctx()) {
81 /******************************************************************************
82 Create an auth_ntlmssp_state and ensure pointer copy is correct.
83 ******************************************************************************/
85 static NTSTATUS
make_auth_ntlmssp(struct smb_srv_trans_enc_ctx
*ec
)
87 NTSTATUS status
= auth_ntlmssp_start(&ec
->auth_ntlmssp_state
);
88 if (!NT_STATUS_IS_OK(status
)) {
89 return nt_status_squash(status
);
93 * We must remember to update the pointer copy for the common
94 * functions after any auth_ntlmssp_start/auth_ntlmssp_end.
96 ec
->es
->s
.ntlmssp_state
= auth_ntlmssp_get_ntlmssp_state(ec
->auth_ntlmssp_state
);
100 /******************************************************************************
101 Destroy an auth_ntlmssp_state and ensure pointer copy is correct.
102 ******************************************************************************/
104 static void destroy_auth_ntlmssp(struct smb_srv_trans_enc_ctx
*ec
)
107 * We must remember to update the pointer copy for the common
108 * functions after any auth_ntlmssp_start/auth_ntlmssp_end.
111 if (ec
->auth_ntlmssp_state
) {
112 TALLOC_FREE(ec
->auth_ntlmssp_state
);
113 /* The auth_ntlmssp_end killed this already. */
114 ec
->es
->s
.ntlmssp_state
= NULL
;
118 #if defined(HAVE_GSSAPI) && defined(HAVE_KRB5)
120 /******************************************************************************
122 ******************************************************************************/
124 static NTSTATUS
get_srv_gss_creds(const char *service
,
126 gss_cred_usage_t cred_type
,
127 gss_cred_id_t
*p_srv_cred
)
132 gss_buffer_desc input_name
;
133 char *host_princ_s
= NULL
;
134 NTSTATUS status
= NT_STATUS_OK
;
136 gss_OID_desc nt_hostbased_service
=
137 {10, CONST_DISCARD(char *,"\x2a\x86\x48\x86\xf7\x12\x01\x02\x01\x04")};
139 if (asprintf(&host_princ_s
, "%s@%s", service
, name
) == -1) {
140 return NT_STATUS_NO_MEMORY
;
143 input_name
.value
= host_princ_s
;
144 input_name
.length
= strlen(host_princ_s
) + 1;
146 ret
= gss_import_name(&min
,
148 &nt_hostbased_service
,
151 DEBUG(10,("get_srv_gss_creds: imported name %s\n",
154 if (ret
!= GSS_S_COMPLETE
) {
155 SAFE_FREE(host_princ_s
);
156 return map_nt_error_from_gss(ret
, min
);
160 * We're accessing the krb5.keytab file here.
161 * ensure we have permissions to do so.
165 ret
= gss_acquire_cred(&min
,
175 if (ret
!= GSS_S_COMPLETE
) {
176 ADS_STATUS adss
= ADS_ERROR_GSS(ret
, min
);
177 DEBUG(10,("get_srv_gss_creds: gss_acquire_cred failed with %s\n",
179 status
= map_nt_error_from_gss(ret
, min
);
182 SAFE_FREE(host_princ_s
);
183 gss_release_name(&min
, &srv_name
);
187 /******************************************************************************
189 Try and get the cifs/server@realm principal first, then fall back to
191 ******************************************************************************/
193 static NTSTATUS
make_auth_gss(struct smb_srv_trans_enc_ctx
*ec
)
196 gss_cred_id_t srv_cred
;
199 name_to_fqdn(fqdn
, global_myname());
202 status
= get_srv_gss_creds("cifs", fqdn
, GSS_C_ACCEPT
, &srv_cred
);
203 if (!NT_STATUS_IS_OK(status
)) {
204 status
= get_srv_gss_creds("host", fqdn
, GSS_C_ACCEPT
, &srv_cred
);
205 if (!NT_STATUS_IS_OK(status
)) {
206 return nt_status_squash(status
);
210 ec
->es
->s
.gss_state
= SMB_MALLOC_P(struct smb_tran_enc_state_gss
);
211 if (!ec
->es
->s
.gss_state
) {
213 gss_release_cred(&min
, &srv_cred
);
214 return NT_STATUS_NO_MEMORY
;
216 ZERO_STRUCTP(ec
->es
->s
.gss_state
);
217 ec
->es
->s
.gss_state
->creds
= srv_cred
;
219 /* No context yet. */
220 ec
->es
->s
.gss_state
->gss_ctx
= GSS_C_NO_CONTEXT
;
226 /******************************************************************************
227 Shutdown a server encryption context.
228 ******************************************************************************/
230 static void srv_free_encryption_context(struct smb_srv_trans_enc_ctx
**pp_ec
)
232 struct smb_srv_trans_enc_ctx
*ec
= *pp_ec
;
239 switch (ec
->es
->smb_enc_type
) {
240 case SMB_TRANS_ENC_NTLM
:
241 destroy_auth_ntlmssp(ec
);
243 #if defined(HAVE_GSSAPI) && defined(HAVE_KRB5)
244 case SMB_TRANS_ENC_GSS
:
248 common_free_encryption_state(&ec
->es
);
255 /******************************************************************************
256 Create a server encryption context.
257 ******************************************************************************/
259 static NTSTATUS
make_srv_encryption_context(enum smb_trans_enc_type smb_enc_type
, struct smb_srv_trans_enc_ctx
**pp_ec
)
261 struct smb_srv_trans_enc_ctx
*ec
;
265 ec
= SMB_MALLOC_P(struct smb_srv_trans_enc_ctx
);
267 return NT_STATUS_NO_MEMORY
;
269 ZERO_STRUCTP(partial_srv_trans_enc_ctx
);
270 ec
->es
= SMB_MALLOC_P(struct smb_trans_enc_state
);
273 return NT_STATUS_NO_MEMORY
;
275 ZERO_STRUCTP(ec
->es
);
276 ec
->es
->smb_enc_type
= smb_enc_type
;
277 switch (smb_enc_type
) {
278 case SMB_TRANS_ENC_NTLM
:
280 NTSTATUS status
= make_auth_ntlmssp(ec
);
281 if (!NT_STATUS_IS_OK(status
)) {
282 srv_free_encryption_context(&ec
);
288 #if defined(HAVE_GSSAPI) && defined(HAVE_KRB5)
289 case SMB_TRANS_ENC_GSS
:
290 /* Acquire our credentials by calling gss_acquire_cred here. */
292 NTSTATUS status
= make_auth_gss(ec
);
293 if (!NT_STATUS_IS_OK(status
)) {
294 srv_free_encryption_context(&ec
);
301 srv_free_encryption_context(&ec
);
302 return NT_STATUS_INVALID_PARAMETER
;
308 /******************************************************************************
309 Free an encryption-allocated buffer.
310 ******************************************************************************/
312 void srv_free_enc_buffer(char *buf
)
314 /* We know this is an smb buffer, and we
315 * didn't malloc, only copy, for a keepalive,
316 * so ignore non-session messages. */
322 if (srv_trans_enc_ctx
) {
323 common_free_enc_buffer(srv_trans_enc_ctx
->es
, buf
);
327 /******************************************************************************
328 Decrypt an incoming buffer.
329 ******************************************************************************/
331 NTSTATUS
srv_decrypt_buffer(char *buf
)
333 /* Ignore non-session messages. */
338 if (srv_trans_enc_ctx
) {
339 return common_decrypt_buffer(srv_trans_enc_ctx
->es
, buf
);
345 /******************************************************************************
346 Encrypt an outgoing buffer. Return the encrypted pointer in buf_out.
347 ******************************************************************************/
349 NTSTATUS
srv_encrypt_buffer(char *buf
, char **buf_out
)
353 /* Ignore non-session messages. */
358 if (srv_trans_enc_ctx
) {
359 return common_encrypt_buffer(srv_trans_enc_ctx
->es
, buf
, buf_out
);
361 /* Not encrypting. */
365 /******************************************************************************
366 Do the gss encryption negotiation. Parameters are in/out.
367 Until success we do everything on the partial enc ctx.
368 ******************************************************************************/
370 #if defined(HAVE_GSSAPI) && defined(HAVE_KRB5)
371 static NTSTATUS
srv_enc_spnego_gss_negotiate(unsigned char **ppdata
, size_t *p_data_size
, DATA_BLOB secblob
)
376 gss_buffer_desc in_buf
, out_buf
;
377 struct smb_tran_enc_state_gss
*gss_state
;
378 DATA_BLOB auth_reply
= data_blob_null
;
379 DATA_BLOB response
= data_blob_null
;
382 if (!partial_srv_trans_enc_ctx
) {
383 status
= make_srv_encryption_context(SMB_TRANS_ENC_GSS
, &partial_srv_trans_enc_ctx
);
384 if (!NT_STATUS_IS_OK(status
)) {
389 gss_state
= partial_srv_trans_enc_ctx
->es
->s
.gss_state
;
391 in_buf
.value
= secblob
.data
;
392 in_buf
.length
= secblob
.length
;
394 out_buf
.value
= NULL
;
399 ret
= gss_accept_sec_context(&min
,
403 GSS_C_NO_CHANNEL_BINDINGS
,
405 NULL
, /* Ignore oids. */
406 &out_buf
, /* To return. */
408 NULL
, /* Ingore time. */
409 NULL
); /* Ignore delegated creds. */
412 status
= gss_err_to_ntstatus(ret
, min
);
413 if (ret
!= GSS_S_COMPLETE
&& ret
!= GSS_S_CONTINUE_NEEDED
) {
417 /* Ensure we've got sign+seal available. */
418 if (ret
== GSS_S_COMPLETE
) {
419 if ((flags
& (GSS_C_INTEG_FLAG
|GSS_C_CONF_FLAG
|GSS_C_REPLAY_FLAG
|GSS_C_SEQUENCE_FLAG
)) !=
420 (GSS_C_INTEG_FLAG
|GSS_C_CONF_FLAG
|GSS_C_REPLAY_FLAG
|GSS_C_SEQUENCE_FLAG
)) {
421 DEBUG(0,("srv_enc_spnego_gss_negotiate: quality of service not good enough "
422 "for SMB sealing.\n"));
423 gss_release_buffer(&min
, &out_buf
);
424 return NT_STATUS_ACCESS_DENIED
;
428 auth_reply
= data_blob(out_buf
.value
, out_buf
.length
);
429 gss_release_buffer(&min
, &out_buf
);
431 /* Wrap in SPNEGO. */
432 response
= spnego_gen_auth_response(talloc_tos(), &auth_reply
, status
, OID_KERBEROS5
);
433 data_blob_free(&auth_reply
);
436 *ppdata
= (unsigned char *)memdup(response
.data
, response
.length
);
437 if ((*ppdata
) == NULL
&& response
.length
> 0) {
438 status
= NT_STATUS_NO_MEMORY
;
440 *p_data_size
= response
.length
;
442 data_blob_free(&response
);
448 /******************************************************************************
449 Do the NTLM SPNEGO (or raw) encryption negotiation. Parameters are in/out.
450 Until success we do everything on the partial enc ctx.
451 ******************************************************************************/
453 static NTSTATUS
srv_enc_ntlm_negotiate(unsigned char **ppdata
, size_t *p_data_size
, DATA_BLOB secblob
, bool spnego_wrap
)
456 DATA_BLOB chal
= data_blob_null
;
457 DATA_BLOB response
= data_blob_null
;
459 status
= make_srv_encryption_context(SMB_TRANS_ENC_NTLM
, &partial_srv_trans_enc_ctx
);
460 if (!NT_STATUS_IS_OK(status
)) {
464 status
= auth_ntlmssp_update(partial_srv_trans_enc_ctx
->auth_ntlmssp_state
, secblob
, &chal
);
466 /* status here should be NT_STATUS_MORE_PROCESSING_REQUIRED
470 response
= spnego_gen_auth_response(talloc_tos(), &chal
, status
, OID_NTLMSSP
);
471 data_blob_free(&chal
);
473 /* Return the raw blob. */
478 *ppdata
= (unsigned char *)memdup(response
.data
, response
.length
);
479 if ((*ppdata
) == NULL
&& response
.length
> 0) {
480 status
= NT_STATUS_NO_MEMORY
;
482 *p_data_size
= response
.length
;
483 data_blob_free(&response
);
488 /******************************************************************************
489 Do the SPNEGO encryption negotiation. Parameters are in/out.
490 Based off code in smbd/sesssionsetup.c
491 Until success we do everything on the partial enc ctx.
492 ******************************************************************************/
494 static NTSTATUS
srv_enc_spnego_negotiate(connection_struct
*conn
,
495 unsigned char **ppdata
,
497 unsigned char **pparam
,
498 size_t *p_param_size
)
501 DATA_BLOB blob
= data_blob_null
;
502 DATA_BLOB secblob
= data_blob_null
;
503 char *kerb_mech
= NULL
;
505 blob
= data_blob_const(*ppdata
, *p_data_size
);
507 status
= parse_spnego_mechanisms(talloc_tos(), blob
, &secblob
, &kerb_mech
);
508 if (!NT_STATUS_IS_OK(status
)) {
509 return nt_status_squash(status
);
512 /* We should have no partial context at this point. */
514 srv_free_encryption_context(&partial_srv_trans_enc_ctx
);
517 TALLOC_FREE(kerb_mech
);
519 #if defined(HAVE_GSSAPI) && defined(HAVE_KRB5)
520 status
= srv_enc_spnego_gss_negotiate(ppdata
, p_data_size
, secblob
);
522 /* Currently we don't SPNEGO negotiate
523 * back to NTLMSSP as we do in sessionsetupX. We should... */
524 return NT_STATUS_LOGON_FAILURE
;
527 status
= srv_enc_ntlm_negotiate(ppdata
, p_data_size
, secblob
, true);
530 data_blob_free(&secblob
);
532 if (!NT_STATUS_EQUAL(status
,NT_STATUS_MORE_PROCESSING_REQUIRED
) && !NT_STATUS_IS_OK(status
)) {
533 srv_free_encryption_context(&partial_srv_trans_enc_ctx
);
534 return nt_status_squash(status
);
537 if (NT_STATUS_IS_OK(status
)) {
538 /* Return the context we're using for this encryption state. */
539 if (!(*pparam
= SMB_MALLOC_ARRAY(unsigned char, 2))) {
540 return NT_STATUS_NO_MEMORY
;
542 SSVAL(*pparam
,0,partial_srv_trans_enc_ctx
->es
->enc_ctx_num
);
549 /******************************************************************************
550 Complete a SPNEGO encryption negotiation. Parameters are in/out.
551 We only get this for a NTLM auth second stage.
552 ******************************************************************************/
554 static NTSTATUS
srv_enc_spnego_ntlm_auth(connection_struct
*conn
,
555 unsigned char **ppdata
,
557 unsigned char **pparam
,
558 size_t *p_param_size
)
561 DATA_BLOB blob
= data_blob_null
;
562 DATA_BLOB auth
= data_blob_null
;
563 DATA_BLOB auth_reply
= data_blob_null
;
564 DATA_BLOB response
= data_blob_null
;
565 struct smb_srv_trans_enc_ctx
*ec
= partial_srv_trans_enc_ctx
;
567 /* We must have a partial context here. */
569 if (!ec
|| !ec
->es
|| ec
->auth_ntlmssp_state
== NULL
|| ec
->es
->smb_enc_type
!= SMB_TRANS_ENC_NTLM
) {
570 srv_free_encryption_context(&partial_srv_trans_enc_ctx
);
571 return NT_STATUS_INVALID_PARAMETER
;
574 blob
= data_blob_const(*ppdata
, *p_data_size
);
575 if (!spnego_parse_auth(talloc_tos(), blob
, &auth
)) {
576 srv_free_encryption_context(&partial_srv_trans_enc_ctx
);
577 return NT_STATUS_INVALID_PARAMETER
;
580 status
= auth_ntlmssp_update(ec
->auth_ntlmssp_state
, auth
, &auth_reply
);
581 data_blob_free(&auth
);
587 * This field SHALL only be present in the first reply from the
589 * So set mechOID to NULL here.
592 response
= spnego_gen_auth_response(talloc_tos(), &auth_reply
, status
, NULL
);
593 data_blob_free(&auth_reply
);
595 if (NT_STATUS_IS_OK(status
)) {
596 /* Return the context we're using for this encryption state. */
597 if (!(*pparam
= SMB_MALLOC_ARRAY(unsigned char, 2))) {
598 return NT_STATUS_NO_MEMORY
;
600 SSVAL(*pparam
,0,ec
->es
->enc_ctx_num
);
605 *ppdata
= (unsigned char *)memdup(response
.data
, response
.length
);
606 if ((*ppdata
) == NULL
&& response
.length
> 0)
607 return NT_STATUS_NO_MEMORY
;
608 *p_data_size
= response
.length
;
609 data_blob_free(&response
);
613 /******************************************************************************
614 Raw NTLM encryption negotiation. Parameters are in/out.
615 This function does both steps.
616 ******************************************************************************/
618 static NTSTATUS
srv_enc_raw_ntlm_auth(connection_struct
*conn
,
619 unsigned char **ppdata
,
621 unsigned char **pparam
,
622 size_t *p_param_size
)
625 DATA_BLOB blob
= data_blob_const(*ppdata
, *p_data_size
);
626 DATA_BLOB response
= data_blob_null
;
627 struct smb_srv_trans_enc_ctx
*ec
;
629 if (!partial_srv_trans_enc_ctx
) {
630 /* This is the initial step. */
631 status
= srv_enc_ntlm_negotiate(ppdata
, p_data_size
, blob
, false);
632 if (!NT_STATUS_EQUAL(status
,NT_STATUS_MORE_PROCESSING_REQUIRED
) && !NT_STATUS_IS_OK(status
)) {
633 srv_free_encryption_context(&partial_srv_trans_enc_ctx
);
634 return nt_status_squash(status
);
639 ec
= partial_srv_trans_enc_ctx
;
640 if (!ec
|| !ec
->es
|| ec
->auth_ntlmssp_state
== NULL
|| ec
->es
->smb_enc_type
!= SMB_TRANS_ENC_NTLM
) {
641 srv_free_encryption_context(&partial_srv_trans_enc_ctx
);
642 return NT_STATUS_INVALID_PARAMETER
;
646 status
= auth_ntlmssp_update(partial_srv_trans_enc_ctx
->auth_ntlmssp_state
, blob
, &response
);
648 if (NT_STATUS_IS_OK(status
)) {
649 /* Return the context we're using for this encryption state. */
650 if (!(*pparam
= SMB_MALLOC_ARRAY(unsigned char, 2))) {
651 return NT_STATUS_NO_MEMORY
;
653 SSVAL(*pparam
,0,ec
->es
->enc_ctx_num
);
657 /* Return the raw blob. */
659 *ppdata
= (unsigned char *)memdup(response
.data
, response
.length
);
660 if ((*ppdata
) == NULL
&& response
.length
> 0)
661 return NT_STATUS_NO_MEMORY
;
662 *p_data_size
= response
.length
;
663 data_blob_free(&response
);
667 /******************************************************************************
668 Do the SPNEGO encryption negotiation. Parameters are in/out.
669 ******************************************************************************/
671 NTSTATUS
srv_request_encryption_setup(connection_struct
*conn
,
672 unsigned char **ppdata
,
674 unsigned char **pparam
,
675 size_t *p_param_size
)
677 unsigned char *pdata
= *ppdata
;
682 if (*p_data_size
< 1) {
683 return NT_STATUS_INVALID_PARAMETER
;
686 if (pdata
[0] == ASN1_APPLICATION(0)) {
687 /* its a negTokenTarg packet */
688 return srv_enc_spnego_negotiate(conn
, ppdata
, p_data_size
, pparam
, p_param_size
);
691 if (pdata
[0] == ASN1_CONTEXT(1)) {
692 /* It's an auth packet */
693 return srv_enc_spnego_ntlm_auth(conn
, ppdata
, p_data_size
, pparam
, p_param_size
);
696 /* Maybe it's a raw unwrapped auth ? */
697 if (*p_data_size
< 7) {
698 return NT_STATUS_INVALID_PARAMETER
;
701 if (strncmp((char *)pdata
, "NTLMSSP", 7) == 0) {
702 return srv_enc_raw_ntlm_auth(conn
, ppdata
, p_data_size
, pparam
, p_param_size
);
705 DEBUG(1,("srv_request_encryption_setup: Unknown packet\n"));
707 return NT_STATUS_LOGON_FAILURE
;
710 /******************************************************************************
711 Negotiation was successful - turn on server-side encryption.
712 ******************************************************************************/
714 static NTSTATUS
check_enc_good(struct smb_srv_trans_enc_ctx
*ec
)
716 if (!ec
|| !ec
->es
) {
717 return NT_STATUS_LOGON_FAILURE
;
720 if (ec
->es
->smb_enc_type
== SMB_TRANS_ENC_NTLM
) {
721 if (!auth_ntlmssp_negotiated_sign((ec
->auth_ntlmssp_state
))) {
722 return NT_STATUS_INVALID_PARAMETER
;
725 if (!auth_ntlmssp_negotiated_seal((ec
->auth_ntlmssp_state
))) {
726 return NT_STATUS_INVALID_PARAMETER
;
729 /* Todo - check gssapi case. */
734 /******************************************************************************
735 Negotiation was successful - turn on server-side encryption.
736 ******************************************************************************/
738 NTSTATUS
srv_encryption_start(connection_struct
*conn
)
742 /* Check that we are really doing sign+seal. */
743 status
= check_enc_good(partial_srv_trans_enc_ctx
);
744 if (!NT_STATUS_IS_OK(status
)) {
747 /* Throw away the context we're using currently (if any). */
748 srv_free_encryption_context(&srv_trans_enc_ctx
);
750 /* Steal the partial pointer. Deliberate shallow copy. */
751 srv_trans_enc_ctx
= partial_srv_trans_enc_ctx
;
752 srv_trans_enc_ctx
->es
->enc_on
= true;
754 partial_srv_trans_enc_ctx
= NULL
;
756 DEBUG(1,("srv_encryption_start: context negotiated\n"));
760 /******************************************************************************
761 Shutdown all server contexts.
762 ******************************************************************************/
764 void server_encryption_shutdown(void)
766 srv_free_encryption_context(&partial_srv_trans_enc_ctx
);
767 srv_free_encryption_context(&srv_trans_enc_ctx
);