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/globals.h"
23 /******************************************************************************
24 Server side encryption.
25 ******************************************************************************/
27 /******************************************************************************
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 /******************************************************************************
37 Return global enc context - this must change if we ever do multiple contexts.
38 ******************************************************************************/
40 uint16_t srv_enc_ctx(void)
42 return srv_trans_enc_ctx
->es
->enc_ctx_num
;
45 /******************************************************************************
46 Is this an incoming encrypted packet ?
47 ******************************************************************************/
49 bool is_encrypted_packet(const uint8_t *inbuf
)
54 /* Ignore non-session messages or non 0xFF'E' messages. */
55 if(CVAL(inbuf
,0) || !(inbuf
[4] == 0xFF && inbuf
[5] == 'E')) {
59 status
= get_enc_ctx_num(inbuf
, &enc_num
);
60 if (!NT_STATUS_IS_OK(status
)) {
64 /* Encrypted messages are 0xFF'E'<ctx> */
65 if (srv_trans_enc_ctx
&& enc_num
== srv_enc_ctx()) {
71 /******************************************************************************
72 Create an auth_ntlmssp_state and ensure pointer copy is correct.
73 ******************************************************************************/
75 static NTSTATUS
make_auth_ntlmssp(struct smb_srv_trans_enc_ctx
*ec
)
77 NTSTATUS status
= auth_ntlmssp_start(&ec
->auth_ntlmssp_state
);
78 if (!NT_STATUS_IS_OK(status
)) {
79 return nt_status_squash(status
);
83 * We must remember to update the pointer copy for the common
84 * functions after any auth_ntlmssp_start/auth_ntlmssp_end.
86 ec
->es
->s
.ntlmssp_state
= ec
->auth_ntlmssp_state
->ntlmssp_state
;
90 /******************************************************************************
91 Destroy an auth_ntlmssp_state and ensure pointer copy is correct.
92 ******************************************************************************/
94 static void destroy_auth_ntlmssp(struct smb_srv_trans_enc_ctx
*ec
)
97 * We must remember to update the pointer copy for the common
98 * functions after any auth_ntlmssp_start/auth_ntlmssp_end.
101 if (ec
->auth_ntlmssp_state
) {
102 auth_ntlmssp_end(&ec
->auth_ntlmssp_state
);
103 /* The auth_ntlmssp_end killed this already. */
104 ec
->es
->s
.ntlmssp_state
= NULL
;
108 #if defined(HAVE_GSSAPI) && defined(HAVE_KRB5)
110 /******************************************************************************
112 ******************************************************************************/
114 static NTSTATUS
get_srv_gss_creds(const char *service
,
116 gss_cred_usage_t cred_type
,
117 gss_cred_id_t
*p_srv_cred
)
122 gss_buffer_desc input_name
;
123 char *host_princ_s
= NULL
;
124 NTSTATUS status
= NT_STATUS_OK
;
126 gss_OID_desc nt_hostbased_service
=
127 {10, CONST_DISCARD(char *,"\x2a\x86\x48\x86\xf7\x12\x01\x02\x01\x04")};
129 if (asprintf(&host_princ_s
, "%s@%s", service
, name
) == -1) {
130 return NT_STATUS_NO_MEMORY
;
133 input_name
.value
= host_princ_s
;
134 input_name
.length
= strlen(host_princ_s
) + 1;
136 ret
= gss_import_name(&min
,
138 &nt_hostbased_service
,
141 DEBUG(10,("get_srv_gss_creds: imported name %s\n",
144 if (ret
!= GSS_S_COMPLETE
) {
145 SAFE_FREE(host_princ_s
);
146 return map_nt_error_from_gss(ret
, min
);
150 * We're accessing the krb5.keytab file here.
151 * ensure we have permissions to do so.
155 ret
= gss_acquire_cred(&min
,
165 if (ret
!= GSS_S_COMPLETE
) {
166 ADS_STATUS adss
= ADS_ERROR_GSS(ret
, min
);
167 DEBUG(10,("get_srv_gss_creds: gss_acquire_cred failed with %s\n",
169 status
= map_nt_error_from_gss(ret
, min
);
172 SAFE_FREE(host_princ_s
);
173 gss_release_name(&min
, &srv_name
);
177 /******************************************************************************
179 Try and get the cifs/server@realm principal first, then fall back to
181 ******************************************************************************/
183 static NTSTATUS
make_auth_gss(struct smb_srv_trans_enc_ctx
*ec
)
186 gss_cred_id_t srv_cred
;
189 name_to_fqdn(fqdn
, global_myname());
192 status
= get_srv_gss_creds("cifs", fqdn
, GSS_C_ACCEPT
, &srv_cred
);
193 if (!NT_STATUS_IS_OK(status
)) {
194 status
= get_srv_gss_creds("host", fqdn
, GSS_C_ACCEPT
, &srv_cred
);
195 if (!NT_STATUS_IS_OK(status
)) {
196 return nt_status_squash(status
);
200 ec
->es
->s
.gss_state
= SMB_MALLOC_P(struct smb_tran_enc_state_gss
);
201 if (!ec
->es
->s
.gss_state
) {
203 gss_release_cred(&min
, &srv_cred
);
204 return NT_STATUS_NO_MEMORY
;
206 ZERO_STRUCTP(ec
->es
->s
.gss_state
);
207 ec
->es
->s
.gss_state
->creds
= srv_cred
;
209 /* No context yet. */
210 ec
->es
->s
.gss_state
->gss_ctx
= GSS_C_NO_CONTEXT
;
216 /******************************************************************************
217 Shutdown a server encryption context.
218 ******************************************************************************/
220 static void srv_free_encryption_context(struct smb_srv_trans_enc_ctx
**pp_ec
)
222 struct smb_srv_trans_enc_ctx
*ec
= *pp_ec
;
229 switch (ec
->es
->smb_enc_type
) {
230 case SMB_TRANS_ENC_NTLM
:
231 destroy_auth_ntlmssp(ec
);
233 #if defined(HAVE_GSSAPI) && defined(HAVE_KRB5)
234 case SMB_TRANS_ENC_GSS
:
238 common_free_encryption_state(&ec
->es
);
245 /******************************************************************************
246 Create a server encryption context.
247 ******************************************************************************/
249 static NTSTATUS
make_srv_encryption_context(enum smb_trans_enc_type smb_enc_type
, struct smb_srv_trans_enc_ctx
**pp_ec
)
251 struct smb_srv_trans_enc_ctx
*ec
;
255 ec
= SMB_MALLOC_P(struct smb_srv_trans_enc_ctx
);
257 return NT_STATUS_NO_MEMORY
;
259 ZERO_STRUCTP(partial_srv_trans_enc_ctx
);
260 ec
->es
= SMB_MALLOC_P(struct smb_trans_enc_state
);
263 return NT_STATUS_NO_MEMORY
;
265 ZERO_STRUCTP(ec
->es
);
266 ec
->es
->smb_enc_type
= smb_enc_type
;
267 switch (smb_enc_type
) {
268 case SMB_TRANS_ENC_NTLM
:
270 NTSTATUS status
= make_auth_ntlmssp(ec
);
271 if (!NT_STATUS_IS_OK(status
)) {
272 srv_free_encryption_context(&ec
);
278 #if defined(HAVE_GSSAPI) && defined(HAVE_KRB5)
279 case SMB_TRANS_ENC_GSS
:
280 /* Acquire our credentials by calling gss_acquire_cred here. */
282 NTSTATUS status
= make_auth_gss(ec
);
283 if (!NT_STATUS_IS_OK(status
)) {
284 srv_free_encryption_context(&ec
);
291 srv_free_encryption_context(&ec
);
292 return NT_STATUS_INVALID_PARAMETER
;
298 /******************************************************************************
299 Free an encryption-allocated buffer.
300 ******************************************************************************/
302 void srv_free_enc_buffer(char *buf
)
304 /* We know this is an smb buffer, and we
305 * didn't malloc, only copy, for a keepalive,
306 * so ignore non-session messages. */
312 if (srv_trans_enc_ctx
) {
313 common_free_enc_buffer(srv_trans_enc_ctx
->es
, buf
);
317 /******************************************************************************
318 Decrypt an incoming buffer.
319 ******************************************************************************/
321 NTSTATUS
srv_decrypt_buffer(char *buf
)
323 /* Ignore non-session messages. */
328 if (srv_trans_enc_ctx
) {
329 return common_decrypt_buffer(srv_trans_enc_ctx
->es
, buf
);
335 /******************************************************************************
336 Encrypt an outgoing buffer. Return the encrypted pointer in buf_out.
337 ******************************************************************************/
339 NTSTATUS
srv_encrypt_buffer(char *buf
, char **buf_out
)
343 /* Ignore non-session messages. */
348 if (srv_trans_enc_ctx
) {
349 return common_encrypt_buffer(srv_trans_enc_ctx
->es
, buf
, buf_out
);
351 /* Not encrypting. */
355 /******************************************************************************
356 Do the gss encryption negotiation. Parameters are in/out.
357 Until success we do everything on the partial enc ctx.
358 ******************************************************************************/
360 #if defined(HAVE_GSSAPI) && defined(HAVE_KRB5)
361 static NTSTATUS
srv_enc_spnego_gss_negotiate(unsigned char **ppdata
, size_t *p_data_size
, DATA_BLOB secblob
)
366 gss_buffer_desc in_buf
, out_buf
;
367 struct smb_tran_enc_state_gss
*gss_state
;
368 DATA_BLOB auth_reply
= data_blob_null
;
369 DATA_BLOB response
= data_blob_null
;
372 if (!partial_srv_trans_enc_ctx
) {
373 status
= make_srv_encryption_context(SMB_TRANS_ENC_GSS
, &partial_srv_trans_enc_ctx
);
374 if (!NT_STATUS_IS_OK(status
)) {
379 gss_state
= partial_srv_trans_enc_ctx
->es
->s
.gss_state
;
381 in_buf
.value
= secblob
.data
;
382 in_buf
.length
= secblob
.length
;
384 out_buf
.value
= NULL
;
389 ret
= gss_accept_sec_context(&min
,
393 GSS_C_NO_CHANNEL_BINDINGS
,
395 NULL
, /* Ignore oids. */
396 &out_buf
, /* To return. */
398 NULL
, /* Ingore time. */
399 NULL
); /* Ignore delegated creds. */
402 status
= gss_err_to_ntstatus(ret
, min
);
403 if (ret
!= GSS_S_COMPLETE
&& ret
!= GSS_S_CONTINUE_NEEDED
) {
407 /* Ensure we've got sign+seal available. */
408 if (ret
== GSS_S_COMPLETE
) {
409 if ((flags
& (GSS_C_INTEG_FLAG
|GSS_C_CONF_FLAG
|GSS_C_REPLAY_FLAG
|GSS_C_SEQUENCE_FLAG
)) !=
410 (GSS_C_INTEG_FLAG
|GSS_C_CONF_FLAG
|GSS_C_REPLAY_FLAG
|GSS_C_SEQUENCE_FLAG
)) {
411 DEBUG(0,("srv_enc_spnego_gss_negotiate: quality of service not good enough "
412 "for SMB sealing.\n"));
413 gss_release_buffer(&min
, &out_buf
);
414 return NT_STATUS_ACCESS_DENIED
;
418 auth_reply
= data_blob(out_buf
.value
, out_buf
.length
);
419 gss_release_buffer(&min
, &out_buf
);
421 /* Wrap in SPNEGO. */
422 response
= spnego_gen_auth_response(&auth_reply
, status
, OID_KERBEROS5
);
423 data_blob_free(&auth_reply
);
426 *ppdata
= (unsigned char *)memdup(response
.data
, response
.length
);
427 if ((*ppdata
) == NULL
&& response
.length
> 0) {
428 status
= NT_STATUS_NO_MEMORY
;
430 *p_data_size
= response
.length
;
432 data_blob_free(&response
);
438 /******************************************************************************
439 Do the NTLM SPNEGO (or raw) encryption negotiation. Parameters are in/out.
440 Until success we do everything on the partial enc ctx.
441 ******************************************************************************/
443 static NTSTATUS
srv_enc_ntlm_negotiate(unsigned char **ppdata
, size_t *p_data_size
, DATA_BLOB secblob
, bool spnego_wrap
)
446 DATA_BLOB chal
= data_blob_null
;
447 DATA_BLOB response
= data_blob_null
;
449 status
= make_srv_encryption_context(SMB_TRANS_ENC_NTLM
, &partial_srv_trans_enc_ctx
);
450 if (!NT_STATUS_IS_OK(status
)) {
454 status
= auth_ntlmssp_update(partial_srv_trans_enc_ctx
->auth_ntlmssp_state
, secblob
, &chal
);
456 /* status here should be NT_STATUS_MORE_PROCESSING_REQUIRED
460 response
= spnego_gen_auth_response(&chal
, status
, OID_NTLMSSP
);
461 data_blob_free(&chal
);
463 /* Return the raw blob. */
468 *ppdata
= (unsigned char *)memdup(response
.data
, response
.length
);
469 if ((*ppdata
) == NULL
&& response
.length
> 0) {
470 status
= NT_STATUS_NO_MEMORY
;
472 *p_data_size
= response
.length
;
473 data_blob_free(&response
);
478 /******************************************************************************
479 Do the SPNEGO encryption negotiation. Parameters are in/out.
480 Based off code in smbd/sesssionsetup.c
481 Until success we do everything on the partial enc ctx.
482 ******************************************************************************/
484 static NTSTATUS
srv_enc_spnego_negotiate(connection_struct
*conn
,
485 unsigned char **ppdata
,
487 unsigned char **pparam
,
488 size_t *p_param_size
)
491 DATA_BLOB blob
= data_blob_null
;
492 DATA_BLOB secblob
= data_blob_null
;
493 char *kerb_mech
= NULL
;
495 blob
= data_blob_const(*ppdata
, *p_data_size
);
497 status
= parse_spnego_mechanisms(blob
, &secblob
, &kerb_mech
);
498 if (!NT_STATUS_IS_OK(status
)) {
499 return nt_status_squash(status
);
502 /* We should have no partial context at this point. */
504 srv_free_encryption_context(&partial_srv_trans_enc_ctx
);
507 SAFE_FREE(kerb_mech
);
509 #if defined(HAVE_GSSAPI) && defined(HAVE_KRB5)
510 status
= srv_enc_spnego_gss_negotiate(ppdata
, p_data_size
, secblob
);
512 /* Currently we don't SPNEGO negotiate
513 * back to NTLMSSP as we do in sessionsetupX. We should... */
514 return NT_STATUS_LOGON_FAILURE
;
517 status
= srv_enc_ntlm_negotiate(ppdata
, p_data_size
, secblob
, true);
520 data_blob_free(&secblob
);
522 if (!NT_STATUS_EQUAL(status
,NT_STATUS_MORE_PROCESSING_REQUIRED
) && !NT_STATUS_IS_OK(status
)) {
523 srv_free_encryption_context(&partial_srv_trans_enc_ctx
);
524 return nt_status_squash(status
);
527 if (NT_STATUS_IS_OK(status
)) {
528 /* Return the context we're using for this encryption state. */
529 if (!(*pparam
= SMB_MALLOC_ARRAY(unsigned char, 2))) {
530 return NT_STATUS_NO_MEMORY
;
532 SSVAL(*pparam
,0,partial_srv_trans_enc_ctx
->es
->enc_ctx_num
);
539 /******************************************************************************
540 Complete a SPNEGO encryption negotiation. Parameters are in/out.
541 We only get this for a NTLM auth second stage.
542 ******************************************************************************/
544 static NTSTATUS
srv_enc_spnego_ntlm_auth(connection_struct
*conn
,
545 unsigned char **ppdata
,
547 unsigned char **pparam
,
548 size_t *p_param_size
)
551 DATA_BLOB blob
= data_blob_null
;
552 DATA_BLOB auth
= data_blob_null
;
553 DATA_BLOB auth_reply
= data_blob_null
;
554 DATA_BLOB response
= data_blob_null
;
555 struct smb_srv_trans_enc_ctx
*ec
= partial_srv_trans_enc_ctx
;
557 /* We must have a partial context here. */
559 if (!ec
|| !ec
->es
|| ec
->auth_ntlmssp_state
== NULL
|| ec
->es
->smb_enc_type
!= SMB_TRANS_ENC_NTLM
) {
560 srv_free_encryption_context(&partial_srv_trans_enc_ctx
);
561 return NT_STATUS_INVALID_PARAMETER
;
564 blob
= data_blob_const(*ppdata
, *p_data_size
);
565 if (!spnego_parse_auth(blob
, &auth
)) {
566 srv_free_encryption_context(&partial_srv_trans_enc_ctx
);
567 return NT_STATUS_INVALID_PARAMETER
;
570 status
= auth_ntlmssp_update(ec
->auth_ntlmssp_state
, auth
, &auth_reply
);
571 data_blob_free(&auth
);
577 * This field SHALL only be present in the first reply from the
579 * So set mechOID to NULL here.
582 response
= spnego_gen_auth_response(&auth_reply
, status
, NULL
);
583 data_blob_free(&auth_reply
);
585 if (NT_STATUS_IS_OK(status
)) {
586 /* Return the context we're using for this encryption state. */
587 if (!(*pparam
= SMB_MALLOC_ARRAY(unsigned char, 2))) {
588 return NT_STATUS_NO_MEMORY
;
590 SSVAL(*pparam
,0,ec
->es
->enc_ctx_num
);
595 *ppdata
= (unsigned char *)memdup(response
.data
, response
.length
);
596 if ((*ppdata
) == NULL
&& response
.length
> 0)
597 return NT_STATUS_NO_MEMORY
;
598 *p_data_size
= response
.length
;
599 data_blob_free(&response
);
603 /******************************************************************************
604 Raw NTLM encryption negotiation. Parameters are in/out.
605 This function does both steps.
606 ******************************************************************************/
608 static NTSTATUS
srv_enc_raw_ntlm_auth(connection_struct
*conn
,
609 unsigned char **ppdata
,
611 unsigned char **pparam
,
612 size_t *p_param_size
)
615 DATA_BLOB blob
= data_blob_const(*ppdata
, *p_data_size
);
616 DATA_BLOB response
= data_blob_null
;
617 struct smb_srv_trans_enc_ctx
*ec
;
619 if (!partial_srv_trans_enc_ctx
) {
620 /* This is the initial step. */
621 status
= srv_enc_ntlm_negotiate(ppdata
, p_data_size
, blob
, false);
622 if (!NT_STATUS_EQUAL(status
,NT_STATUS_MORE_PROCESSING_REQUIRED
) && !NT_STATUS_IS_OK(status
)) {
623 srv_free_encryption_context(&partial_srv_trans_enc_ctx
);
624 return nt_status_squash(status
);
629 ec
= partial_srv_trans_enc_ctx
;
630 if (!ec
|| !ec
->es
|| ec
->auth_ntlmssp_state
== NULL
|| ec
->es
->smb_enc_type
!= SMB_TRANS_ENC_NTLM
) {
631 srv_free_encryption_context(&partial_srv_trans_enc_ctx
);
632 return NT_STATUS_INVALID_PARAMETER
;
636 status
= auth_ntlmssp_update(partial_srv_trans_enc_ctx
->auth_ntlmssp_state
, blob
, &response
);
638 if (NT_STATUS_IS_OK(status
)) {
639 /* Return the context we're using for this encryption state. */
640 if (!(*pparam
= SMB_MALLOC_ARRAY(unsigned char, 2))) {
641 return NT_STATUS_NO_MEMORY
;
643 SSVAL(*pparam
,0,ec
->es
->enc_ctx_num
);
647 /* Return the raw blob. */
649 *ppdata
= (unsigned char *)memdup(response
.data
, response
.length
);
650 if ((*ppdata
) == NULL
&& response
.length
> 0)
651 return NT_STATUS_NO_MEMORY
;
652 *p_data_size
= response
.length
;
653 data_blob_free(&response
);
657 /******************************************************************************
658 Do the SPNEGO encryption negotiation. Parameters are in/out.
659 ******************************************************************************/
661 NTSTATUS
srv_request_encryption_setup(connection_struct
*conn
,
662 unsigned char **ppdata
,
664 unsigned char **pparam
,
665 size_t *p_param_size
)
667 unsigned char *pdata
= *ppdata
;
672 if (*p_data_size
< 1) {
673 return NT_STATUS_INVALID_PARAMETER
;
676 if (pdata
[0] == ASN1_APPLICATION(0)) {
677 /* its a negTokenTarg packet */
678 return srv_enc_spnego_negotiate(conn
, ppdata
, p_data_size
, pparam
, p_param_size
);
681 if (pdata
[0] == ASN1_CONTEXT(1)) {
682 /* It's an auth packet */
683 return srv_enc_spnego_ntlm_auth(conn
, ppdata
, p_data_size
, pparam
, p_param_size
);
686 /* Maybe it's a raw unwrapped auth ? */
687 if (*p_data_size
< 7) {
688 return NT_STATUS_INVALID_PARAMETER
;
691 if (strncmp((char *)pdata
, "NTLMSSP", 7) == 0) {
692 return srv_enc_raw_ntlm_auth(conn
, ppdata
, p_data_size
, pparam
, p_param_size
);
695 DEBUG(1,("srv_request_encryption_setup: Unknown packet\n"));
697 return NT_STATUS_LOGON_FAILURE
;
700 /******************************************************************************
701 Negotiation was successful - turn on server-side encryption.
702 ******************************************************************************/
704 static NTSTATUS
check_enc_good(struct smb_srv_trans_enc_ctx
*ec
)
706 if (!ec
|| !ec
->es
) {
707 return NT_STATUS_LOGON_FAILURE
;
710 if (ec
->es
->smb_enc_type
== SMB_TRANS_ENC_NTLM
) {
711 if ((ec
->es
->s
.ntlmssp_state
->neg_flags
& (NTLMSSP_NEGOTIATE_SIGN
|NTLMSSP_NEGOTIATE_SEAL
)) !=
712 (NTLMSSP_NEGOTIATE_SIGN
|NTLMSSP_NEGOTIATE_SEAL
)) {
713 return NT_STATUS_INVALID_PARAMETER
;
716 /* Todo - check gssapi case. */
721 /******************************************************************************
722 Negotiation was successful - turn on server-side encryption.
723 ******************************************************************************/
725 NTSTATUS
srv_encryption_start(connection_struct
*conn
)
729 /* Check that we are really doing sign+seal. */
730 status
= check_enc_good(partial_srv_trans_enc_ctx
);
731 if (!NT_STATUS_IS_OK(status
)) {
734 /* Throw away the context we're using currently (if any). */
735 srv_free_encryption_context(&srv_trans_enc_ctx
);
737 /* Steal the partial pointer. Deliberate shallow copy. */
738 srv_trans_enc_ctx
= partial_srv_trans_enc_ctx
;
739 srv_trans_enc_ctx
->es
->enc_on
= true;
741 partial_srv_trans_enc_ctx
= NULL
;
743 DEBUG(1,("srv_encryption_start: context negotiated\n"));
747 /******************************************************************************
748 Shutdown all server contexts.
749 ******************************************************************************/
751 void server_encryption_shutdown(void)
753 srv_free_encryption_context(&partial_srv_trans_enc_ctx
);
754 srv_free_encryption_context(&srv_trans_enc_ctx
);