2 * DCERPC Helper routines
3 * Günther Deschner <gd@samba.org> 2010.
4 * Simo Sorce <idra@samba.org> 2010.
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/>.
22 #include "librpc/rpc/dcerpc.h"
23 #include "librpc/gen_ndr/ndr_dcerpc.h"
24 #include "librpc/gen_ndr/ndr_schannel.h"
25 #include "../libcli/auth/schannel.h"
26 #include "../libcli/auth/spnego.h"
27 #include "librpc/crypto/gse.h"
28 #include "auth/gensec/gensec.h"
31 #define DBGC_CLASS DBGC_RPC_PARSE
34 * @brief NDR Encodes a ncacn_packet
36 * @param mem_ctx The memory context the blob will be allocated on
37 * @param ptype The DCERPC packet type
38 * @param pfc_flags The DCERPC PFC Falgs
39 * @param auth_length The length of the trailing auth blob
40 * @param call_id The call ID
41 * @param u The payload of the packet
42 * @param blob [out] The encoded blob if successful
44 * @return an NTSTATUS error code
46 NTSTATUS
dcerpc_push_ncacn_packet(TALLOC_CTX
*mem_ctx
,
47 enum dcerpc_pkt_type ptype
,
51 union dcerpc_payload
*u
,
54 struct ncacn_packet r
;
55 enum ndr_err_code ndr_err
;
60 r
.pfc_flags
= pfc_flags
;
61 r
.drep
[0] = DCERPC_DREP_LE
;
65 r
.auth_length
= auth_length
;
69 ndr_err
= ndr_push_struct_blob(blob
, mem_ctx
, &r
,
70 (ndr_push_flags_fn_t
)ndr_push_ncacn_packet
);
71 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err
)) {
72 return ndr_map_error2ntstatus(ndr_err
);
75 dcerpc_set_frag_length(blob
, blob
->length
);
78 if (DEBUGLEVEL
>= 10) {
79 /* set frag len for print function */
80 r
.frag_length
= blob
->length
;
81 NDR_PRINT_DEBUG(ncacn_packet
, &r
);
88 * @brief Decodes a ncacn_packet
90 * @param mem_ctx The memory context on which to allocate the packet
92 * @param blob The blob of data to decode
93 * @param r An empty ncacn_packet, must not be NULL
94 * @param bigendian Whether the packet is bignedian encoded
96 * @return a NTSTATUS error code
98 NTSTATUS
dcerpc_pull_ncacn_packet(TALLOC_CTX
*mem_ctx
,
99 const DATA_BLOB
*blob
,
100 struct ncacn_packet
*r
,
103 enum ndr_err_code ndr_err
;
104 struct ndr_pull
*ndr
;
106 ndr
= ndr_pull_init_blob(blob
, mem_ctx
);
108 return NT_STATUS_NO_MEMORY
;
111 ndr
->flags
|= LIBNDR_FLAG_BIGENDIAN
;
114 ndr_err
= ndr_pull_ncacn_packet(ndr
, NDR_SCALARS
|NDR_BUFFERS
, r
);
116 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err
)) {
118 return ndr_map_error2ntstatus(ndr_err
);
122 if (DEBUGLEVEL
>= 10) {
123 NDR_PRINT_DEBUG(ncacn_packet
, r
);
130 * @brief NDR Encodes a NL_AUTH_MESSAGE
132 * @param mem_ctx The memory context the blob will be allocated on
133 * @param r The NL_AUTH_MESSAGE to encode
134 * @param blob [out] The encoded blob if successful
136 * @return a NTSTATUS error code
138 NTSTATUS
dcerpc_push_schannel_bind(TALLOC_CTX
*mem_ctx
,
139 struct NL_AUTH_MESSAGE
*r
,
142 enum ndr_err_code ndr_err
;
144 ndr_err
= ndr_push_struct_blob(blob
, mem_ctx
, r
,
145 (ndr_push_flags_fn_t
)ndr_push_NL_AUTH_MESSAGE
);
146 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err
)) {
147 return ndr_map_error2ntstatus(ndr_err
);
150 if (DEBUGLEVEL
>= 10) {
151 NDR_PRINT_DEBUG(NL_AUTH_MESSAGE
, r
);
158 * @brief NDR Encodes a dcerpc_auth structure
160 * @param mem_ctx The memory context the blob will be allocated on
161 * @param auth_type The DCERPC Authentication Type
162 * @param auth_level The DCERPC Authentication Level
163 * @param auth_pad_length The padding added to the packet this blob will be
165 * @param auth_context_id The context id
166 * @param credentials The authentication credentials blob (signature)
167 * @param blob [out] The encoded blob if successful
169 * @return a NTSTATUS error code
171 NTSTATUS
dcerpc_push_dcerpc_auth(TALLOC_CTX
*mem_ctx
,
172 enum dcerpc_AuthType auth_type
,
173 enum dcerpc_AuthLevel auth_level
,
174 uint8_t auth_pad_length
,
175 uint32_t auth_context_id
,
176 const DATA_BLOB
*credentials
,
179 struct dcerpc_auth r
;
180 enum ndr_err_code ndr_err
;
182 r
.auth_type
= auth_type
;
183 r
.auth_level
= auth_level
;
184 r
.auth_pad_length
= auth_pad_length
;
186 r
.auth_context_id
= auth_context_id
;
187 r
.credentials
= *credentials
;
189 ndr_err
= ndr_push_struct_blob(blob
, mem_ctx
, &r
,
190 (ndr_push_flags_fn_t
)ndr_push_dcerpc_auth
);
191 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err
)) {
192 return ndr_map_error2ntstatus(ndr_err
);
195 if (DEBUGLEVEL
>= 10) {
196 NDR_PRINT_DEBUG(dcerpc_auth
, &r
);
203 * @brief Decodes a dcerpc_auth blob
205 * @param mem_ctx The memory context on which to allocate the packet
207 * @param blob The blob of data to decode
208 * @param r An empty dcerpc_auth structure, must not be NULL
210 * @return a NTSTATUS error code
212 NTSTATUS
dcerpc_pull_dcerpc_auth(TALLOC_CTX
*mem_ctx
,
213 const DATA_BLOB
*blob
,
214 struct dcerpc_auth
*r
,
217 enum ndr_err_code ndr_err
;
218 struct ndr_pull
*ndr
;
220 ndr
= ndr_pull_init_blob(blob
, mem_ctx
);
222 return NT_STATUS_NO_MEMORY
;
225 ndr
->flags
|= LIBNDR_FLAG_BIGENDIAN
;
228 ndr_err
= ndr_pull_dcerpc_auth(ndr
, NDR_SCALARS
|NDR_BUFFERS
, r
);
230 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err
)) {
232 return ndr_map_error2ntstatus(ndr_err
);
236 if (DEBUGLEVEL
>= 10) {
237 NDR_PRINT_DEBUG(dcerpc_auth
, r
);
244 * @brief Calculate how much data we can in a packet, including calculating
245 * auth token and pad lengths.
247 * @param auth The pipe_auth_data structure for this pipe.
248 * @param header_len The length of the packet header
249 * @param data_left The data left in the send buffer
250 * @param max_xmit_frag The max fragment size.
251 * @param pad_alignment The NDR padding size.
252 * @param data_to_send [out] The max data we will send in the pdu
253 * @param frag_len [out] The total length of the fragment
254 * @param auth_len [out] The length of the auth trailer
255 * @param pad_len [out] The padding to be applied
257 * @return A NT Error status code.
259 NTSTATUS
dcerpc_guess_sizes(struct pipe_auth_data
*auth
,
260 size_t header_len
, size_t data_left
,
261 size_t max_xmit_frag
, size_t pad_alignment
,
262 size_t *data_to_send
, size_t *frag_len
,
263 size_t *auth_len
, size_t *pad_len
)
267 struct gensec_security
*gensec_security
;
268 struct schannel_state
*schannel_auth
;
270 /* no auth token cases first */
271 switch (auth
->auth_level
) {
272 case DCERPC_AUTH_LEVEL_NONE
:
273 case DCERPC_AUTH_LEVEL_CONNECT
:
274 case DCERPC_AUTH_LEVEL_PACKET
:
275 max_len
= max_xmit_frag
- header_len
;
276 *data_to_send
= MIN(max_len
, data_left
);
279 *frag_len
= header_len
+ *data_to_send
;
282 case DCERPC_AUTH_LEVEL_PRIVACY
:
285 case DCERPC_AUTH_LEVEL_INTEGRITY
:
289 return NT_STATUS_INVALID_PARAMETER
;
293 /* Sign/seal case, calculate auth and pad lengths */
295 max_len
= max_xmit_frag
- header_len
- DCERPC_AUTH_TRAILER_LENGTH
;
297 /* Treat the same for all authenticated rpc requests. */
298 switch (auth
->auth_type
) {
299 case DCERPC_AUTH_TYPE_SPNEGO
:
300 case DCERPC_AUTH_TYPE_NTLMSSP
:
301 case DCERPC_AUTH_TYPE_KRB5
:
302 gensec_security
= talloc_get_type_abort(auth
->auth_ctx
,
303 struct gensec_security
);
304 *auth_len
= gensec_sig_size(gensec_security
, max_len
);
307 case DCERPC_AUTH_TYPE_SCHANNEL
:
308 schannel_auth
= talloc_get_type_abort(auth
->auth_ctx
,
309 struct schannel_state
);
310 *auth_len
= netsec_outgoing_sig_size(schannel_auth
);
313 return NT_STATUS_INVALID_PARAMETER
;
316 max_len
-= *auth_len
;
318 *data_to_send
= MIN(max_len
, data_left
);
320 mod_len
= (header_len
+ *data_to_send
) % pad_alignment
;
322 *pad_len
= pad_alignment
- mod_len
;
327 if (*data_to_send
+ *pad_len
> max_len
) {
328 *data_to_send
-= pad_alignment
;
331 *frag_len
= header_len
+ *data_to_send
+ *pad_len
332 + DCERPC_AUTH_TRAILER_LENGTH
+ *auth_len
;
337 /*******************************************************************
338 Create and add the NTLMSSP sign/seal auth data.
339 ********************************************************************/
341 static NTSTATUS
add_generic_auth_footer(struct gensec_security
*gensec_security
,
342 enum dcerpc_AuthLevel auth_level
,
345 uint16_t data_and_pad_len
= rpc_out
->length
346 - DCERPC_RESPONSE_LENGTH
347 - DCERPC_AUTH_TRAILER_LENGTH
;
351 if (!gensec_security
) {
352 return NT_STATUS_INVALID_PARAMETER
;
355 switch (auth_level
) {
356 case DCERPC_AUTH_LEVEL_PRIVACY
:
357 /* Data portion is encrypted. */
358 status
= gensec_seal_packet(gensec_security
,
361 + DCERPC_RESPONSE_LENGTH
,
366 if (!NT_STATUS_IS_OK(status
)) {
371 case DCERPC_AUTH_LEVEL_INTEGRITY
:
372 /* Data is signed. */
373 status
= gensec_sign_packet(gensec_security
,
376 + DCERPC_RESPONSE_LENGTH
,
381 if (!NT_STATUS_IS_OK(status
)) {
388 smb_panic("bad auth level");
390 return NT_STATUS_INVALID_PARAMETER
;
393 /* Finally attach the blob. */
394 if (!data_blob_append(NULL
, rpc_out
,
395 auth_blob
.data
, auth_blob
.length
)) {
396 DEBUG(0, ("Failed to add %u bytes auth blob.\n",
397 (unsigned int)auth_blob
.length
));
398 return NT_STATUS_NO_MEMORY
;
400 data_blob_free(&auth_blob
);
405 /*******************************************************************
406 Check/unseal the NTLMSSP auth data. (Unseal in place).
407 ********************************************************************/
409 static NTSTATUS
get_generic_auth_footer(struct gensec_security
*gensec_security
,
410 enum dcerpc_AuthLevel auth_level
,
411 DATA_BLOB
*data
, DATA_BLOB
*full_pkt
,
412 DATA_BLOB
*auth_token
)
414 switch (auth_level
) {
415 case DCERPC_AUTH_LEVEL_PRIVACY
:
416 /* Data portion is encrypted. */
417 return gensec_unseal_packet(gensec_security
,
424 case DCERPC_AUTH_LEVEL_INTEGRITY
:
425 /* Data is signed. */
426 return gensec_check_packet(gensec_security
,
434 return NT_STATUS_INVALID_PARAMETER
;
438 /*******************************************************************
439 Create and add the schannel sign/seal auth data.
440 ********************************************************************/
442 static NTSTATUS
add_schannel_auth_footer(struct schannel_state
*sas
,
443 enum dcerpc_AuthLevel auth_level
,
446 uint8_t *data_p
= rpc_out
->data
+ DCERPC_RESPONSE_LENGTH
;
447 size_t data_and_pad_len
= rpc_out
->length
448 - DCERPC_RESPONSE_LENGTH
449 - DCERPC_AUTH_TRAILER_LENGTH
;
454 return NT_STATUS_INVALID_PARAMETER
;
457 DEBUG(10,("add_schannel_auth_footer: SCHANNEL seq_num=%d\n",
460 switch (auth_level
) {
461 case DCERPC_AUTH_LEVEL_PRIVACY
:
462 status
= netsec_outgoing_packet(sas
,
469 case DCERPC_AUTH_LEVEL_INTEGRITY
:
470 status
= netsec_outgoing_packet(sas
,
478 status
= NT_STATUS_INTERNAL_ERROR
;
482 if (!NT_STATUS_IS_OK(status
)) {
483 DEBUG(1,("add_schannel_auth_footer: failed to process packet: %s\n",
488 if (DEBUGLEVEL
>= 10) {
489 dump_NL_AUTH_SIGNATURE(talloc_tos(), &auth_blob
);
492 /* Finally attach the blob. */
493 if (!data_blob_append(NULL
, rpc_out
,
494 auth_blob
.data
, auth_blob
.length
)) {
495 return NT_STATUS_NO_MEMORY
;
497 data_blob_free(&auth_blob
);
502 /*******************************************************************
503 Check/unseal the Schannel auth data. (Unseal in place).
504 ********************************************************************/
506 static NTSTATUS
get_schannel_auth_footer(TALLOC_CTX
*mem_ctx
,
507 struct schannel_state
*auth_state
,
508 enum dcerpc_AuthLevel auth_level
,
509 DATA_BLOB
*data
, DATA_BLOB
*full_pkt
,
510 DATA_BLOB
*auth_token
)
512 switch (auth_level
) {
513 case DCERPC_AUTH_LEVEL_PRIVACY
:
514 /* Data portion is encrypted. */
515 return netsec_incoming_packet(auth_state
,
521 case DCERPC_AUTH_LEVEL_INTEGRITY
:
522 /* Data is signed. */
523 return netsec_incoming_packet(auth_state
,
530 return NT_STATUS_INVALID_PARAMETER
;
535 * @brief Append an auth footer according to what is the current mechanism
537 * @param auth The pipe_auth_data associated with the connection
538 * @param pad_len The padding used in the packet
539 * @param rpc_out Packet blob up to and including the auth header
541 * @return A NTSTATUS error code.
543 NTSTATUS
dcerpc_add_auth_footer(struct pipe_auth_data
*auth
,
544 size_t pad_len
, DATA_BLOB
*rpc_out
)
546 struct schannel_state
*schannel_auth
;
547 struct gensec_security
*gensec_security
;
548 char pad
[CLIENT_NDR_PADDING_SIZE
] = { 0, };
553 if (auth
->auth_type
== DCERPC_AUTH_TYPE_NONE
||
554 auth
->auth_type
== DCERPC_AUTH_TYPE_NCALRPC_AS_SYSTEM
) {
559 /* Copy the sign/seal padding data. */
560 if (!data_blob_append(NULL
, rpc_out
, pad
, pad_len
)) {
561 return NT_STATUS_NO_MEMORY
;
565 /* marshall the dcerpc_auth with an actually empty auth_blob.
566 * This is needed because the ntmlssp signature includes the
567 * auth header. We will append the actual blob later. */
568 auth_blob
= data_blob_null
;
569 status
= dcerpc_push_dcerpc_auth(rpc_out
->data
,
576 if (!NT_STATUS_IS_OK(status
)) {
580 /* append the header */
581 if (!data_blob_append(NULL
, rpc_out
,
582 auth_info
.data
, auth_info
.length
)) {
583 DEBUG(0, ("Failed to add %u bytes auth blob.\n",
584 (unsigned int)auth_info
.length
));
585 return NT_STATUS_NO_MEMORY
;
587 data_blob_free(&auth_info
);
589 /* Generate any auth sign/seal and add the auth footer. */
590 switch (auth
->auth_type
) {
591 case DCERPC_AUTH_TYPE_NONE
:
592 case DCERPC_AUTH_TYPE_NCALRPC_AS_SYSTEM
:
593 status
= NT_STATUS_OK
;
595 case DCERPC_AUTH_TYPE_SPNEGO
:
596 case DCERPC_AUTH_TYPE_KRB5
:
597 case DCERPC_AUTH_TYPE_NTLMSSP
:
598 gensec_security
= talloc_get_type_abort(auth
->auth_ctx
,
599 struct gensec_security
);
600 status
= add_generic_auth_footer(gensec_security
,
604 case DCERPC_AUTH_TYPE_SCHANNEL
:
605 schannel_auth
= talloc_get_type_abort(auth
->auth_ctx
,
606 struct schannel_state
);
607 status
= add_schannel_auth_footer(schannel_auth
,
612 status
= NT_STATUS_INVALID_PARAMETER
;
620 * @brief Check authentication for request/response packets
622 * @param auth The auth data for the connection
623 * @param pkt The actual ncacn_packet
624 * @param pkt_trailer The stub_and_verifier part of the packet
625 * @param header_size The header size
626 * @param raw_pkt The whole raw packet data blob
627 * @param pad_len [out] The padding length used in the packet
629 * @return A NTSTATUS error code
631 NTSTATUS
dcerpc_check_auth(struct pipe_auth_data
*auth
,
632 struct ncacn_packet
*pkt
,
633 DATA_BLOB
*pkt_trailer
,
638 struct schannel_state
*schannel_auth
;
639 struct gensec_security
*gensec_security
;
641 struct dcerpc_auth auth_info
;
642 uint32_t auth_length
;
646 switch (auth
->auth_level
) {
647 case DCERPC_AUTH_LEVEL_PRIVACY
:
648 DEBUG(10, ("Requested Privacy.\n"));
651 case DCERPC_AUTH_LEVEL_INTEGRITY
:
652 DEBUG(10, ("Requested Integrity.\n"));
655 case DCERPC_AUTH_LEVEL_CONNECT
:
656 if (pkt
->auth_length
!= 0) {
662 case DCERPC_AUTH_LEVEL_NONE
:
663 if (pkt
->auth_length
!= 0) {
664 DEBUG(3, ("Got non-zero auth len on non "
665 "authenticated connection!\n"));
666 return NT_STATUS_INVALID_PARAMETER
;
672 DEBUG(3, ("Unimplemented Auth Level %d",
674 return NT_STATUS_INVALID_PARAMETER
;
677 /* Paranioa checks for auth_length. */
678 if (pkt
->auth_length
> pkt
->frag_length
) {
679 return NT_STATUS_INFO_LENGTH_MISMATCH
;
681 if (((unsigned int)pkt
->auth_length
682 + DCERPC_AUTH_TRAILER_LENGTH
< (unsigned int)pkt
->auth_length
) ||
683 ((unsigned int)pkt
->auth_length
684 + DCERPC_AUTH_TRAILER_LENGTH
< DCERPC_AUTH_TRAILER_LENGTH
)) {
685 /* Integer wrap attempt. */
686 return NT_STATUS_INFO_LENGTH_MISMATCH
;
689 status
= dcerpc_pull_auth_trailer(pkt
, pkt
, pkt_trailer
,
690 &auth_info
, &auth_length
, false);
691 if (!NT_STATUS_IS_OK(status
)) {
695 data
= data_blob_const(raw_pkt
->data
+ header_size
,
696 pkt_trailer
->length
- auth_length
);
697 full_pkt
= data_blob_const(raw_pkt
->data
,
698 raw_pkt
->length
- auth_info
.credentials
.length
);
700 switch (auth
->auth_type
) {
701 case DCERPC_AUTH_TYPE_NONE
:
702 case DCERPC_AUTH_TYPE_NCALRPC_AS_SYSTEM
:
705 case DCERPC_AUTH_TYPE_SPNEGO
:
706 case DCERPC_AUTH_TYPE_KRB5
:
707 case DCERPC_AUTH_TYPE_NTLMSSP
:
709 DEBUG(10, ("GENSEC auth\n"));
711 gensec_security
= talloc_get_type_abort(auth
->auth_ctx
,
712 struct gensec_security
);
713 status
= get_generic_auth_footer(gensec_security
,
716 &auth_info
.credentials
);
717 if (!NT_STATUS_IS_OK(status
)) {
722 case DCERPC_AUTH_TYPE_SCHANNEL
:
724 DEBUG(10, ("SCHANNEL auth\n"));
726 schannel_auth
= talloc_get_type_abort(auth
->auth_ctx
,
727 struct schannel_state
);
728 status
= get_schannel_auth_footer(pkt
, schannel_auth
,
731 &auth_info
.credentials
);
732 if (!NT_STATUS_IS_OK(status
)) {
738 DEBUG(0, ("process_request_pdu: "
739 "unknown auth type %u set.\n",
740 (unsigned int)auth
->auth_type
));
741 return NT_STATUS_INVALID_PARAMETER
;
744 /* TODO: remove later
745 * this is still needed because in the server code the
746 * pkt_trailer actually has a copy of the raw data, and they
747 * are still both used in later calls */
748 if (auth
->auth_level
== DCERPC_AUTH_LEVEL_PRIVACY
) {
749 memcpy(pkt_trailer
->data
, data
.data
, data
.length
);
752 *pad_len
= auth_info
.auth_pad_length
;
753 data_blob_free(&auth_info
.credentials
);