2 Unix SMB/CIFS implementation.
3 simple kerberos5/SPNEGO routines
4 Copyright (C) Andrew Tridgell 2001
5 Copyright (C) Jim McDonough <jmcd@us.ibm.com> 2002
6 Copyright (C) Luke Howard 2003
7 Copyright (C) Jeremy Allison 2010
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 3 of the License, or
12 (at your option) any later version.
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with this program. If not, see <http://www.gnu.org/licenses/>.
24 #include "../libcli/auth/spnego.h"
26 #include "../lib/util/asn1.h"
29 generate a negTokenInit packet given a list of supported
30 OIDs (the mechanisms) a blob, and a principal name string
33 DATA_BLOB
spnego_gen_negTokenInit(TALLOC_CTX
*ctx
,
36 const char *principal
)
42 data
= asn1_init(talloc_tos());
44 return data_blob_null
;
47 asn1_push_tag(data
,ASN1_APPLICATION(0));
48 asn1_write_OID(data
,OID_SPNEGO
);
49 asn1_push_tag(data
,ASN1_CONTEXT(0));
50 asn1_push_tag(data
,ASN1_SEQUENCE(0));
52 asn1_push_tag(data
,ASN1_CONTEXT(0));
53 asn1_push_tag(data
,ASN1_SEQUENCE(0));
54 for (i
=0; OIDs
[i
]; i
++) {
55 asn1_write_OID(data
,OIDs
[i
]);
60 if (psecblob
&& psecblob
->length
&& psecblob
->data
) {
61 asn1_push_tag(data
, ASN1_CONTEXT(2));
62 asn1_write_OctetString(data
,psecblob
->data
,
68 asn1_push_tag(data
, ASN1_CONTEXT(3));
69 asn1_push_tag(data
, ASN1_SEQUENCE(0));
70 asn1_push_tag(data
, ASN1_CONTEXT(0));
71 asn1_write_GeneralString(data
,principal
);
82 if (data
->has_error
) {
83 DEBUG(1,("Failed to build negTokenInit at offset %d\n", (int)data
->ofs
));
86 ret
= data_blob_talloc(ctx
, data
->data
, data
->length
);
93 parse a negTokenInit packet giving a GUID, a list of supported
94 OIDs (the mechanisms) and a principal name string
96 bool spnego_parse_negTokenInit(TALLOC_CTX
*ctx
,
98 char *OIDs
[ASN1_MAX_OIDS
],
106 data
= asn1_init(talloc_tos());
111 asn1_load(data
, blob
);
113 asn1_start_tag(data
,ASN1_APPLICATION(0));
115 asn1_check_OID(data
,OID_SPNEGO
);
117 /* negTokenInit [0] NegTokenInit */
118 asn1_start_tag(data
,ASN1_CONTEXT(0));
119 asn1_start_tag(data
,ASN1_SEQUENCE(0));
121 /* mechTypes [0] MechTypeList OPTIONAL */
123 /* Not really optional, we depend on this to decide
124 * what mechanisms we have to work with. */
126 asn1_start_tag(data
,ASN1_CONTEXT(0));
127 asn1_start_tag(data
,ASN1_SEQUENCE(0));
128 for (i
=0; asn1_tag_remaining(data
) > 0 && i
< ASN1_MAX_OIDS
-1; i
++) {
129 if (!asn1_read_OID(data
,ctx
, &OIDs
[i
])) {
132 if (data
->has_error
) {
144 *secblob
= data_blob_null
;
148 Win7 + Live Sign-in Assistant attaches a mechToken
149 ASN1_CONTEXT(2) to the negTokenInit packet
150 which breaks our negotiation if we just assume
151 the next tag is ASN1_CONTEXT(3).
154 if (asn1_peek_tag(data
, ASN1_CONTEXT(1))) {
157 /* reqFlags [1] ContextFlags OPTIONAL */
158 asn1_start_tag(data
, ASN1_CONTEXT(1));
159 asn1_start_tag(data
, ASN1_BIT_STRING
);
160 while (asn1_tag_remaining(data
) > 0) {
161 asn1_read_uint8(data
, &flags
);
167 if (asn1_peek_tag(data
, ASN1_CONTEXT(2))) {
168 DATA_BLOB sblob
= data_blob_null
;
169 /* mechToken [2] OCTET STRING OPTIONAL */
170 asn1_start_tag(data
, ASN1_CONTEXT(2));
171 asn1_read_OctetString(data
, ctx
, &sblob
);
176 data_blob_free(&sblob
);
180 if (asn1_peek_tag(data
, ASN1_CONTEXT(3))) {
182 /* mechListMIC [3] OCTET STRING OPTIONAL */
183 asn1_start_tag(data
, ASN1_CONTEXT(3));
184 asn1_start_tag(data
, ASN1_SEQUENCE(0));
185 asn1_start_tag(data
, ASN1_CONTEXT(0));
186 asn1_read_GeneralString(data
, ctx
, &princ
);
202 ret
= !data
->has_error
;
203 if (data
->has_error
) {
206 TALLOC_FREE(*principal
);
209 data_blob_free(secblob
);
211 for(j
= 0; j
< i
&& j
< ASN1_MAX_OIDS
-1; j
++) {
212 TALLOC_FREE(OIDs
[j
]);
221 generate a krb5 GSS-API wrapper packet given a ticket
223 DATA_BLOB
spnego_gen_krb5_wrap(TALLOC_CTX
*ctx
, const DATA_BLOB ticket
, const uint8 tok_id
[2])
228 data
= asn1_init(talloc_tos());
230 return data_blob_null
;
233 asn1_push_tag(data
, ASN1_APPLICATION(0));
234 asn1_write_OID(data
, OID_KERBEROS5
);
236 asn1_write(data
, tok_id
, 2);
237 asn1_write(data
, ticket
.data
, ticket
.length
);
240 if (data
->has_error
) {
241 DEBUG(1,("Failed to build krb5 wrapper at offset %d\n", (int)data
->ofs
));
244 ret
= data_blob_talloc(ctx
, data
->data
, data
->length
);
251 parse a krb5 GSS-API wrapper packet giving a ticket
253 bool spnego_parse_krb5_wrap(TALLOC_CTX
*ctx
, DATA_BLOB blob
, DATA_BLOB
*ticket
, uint8 tok_id
[2])
258 *ticket
= data_blob_null
;
260 data
= asn1_init(talloc_tos());
265 asn1_load(data
, blob
);
266 asn1_start_tag(data
, ASN1_APPLICATION(0));
267 asn1_check_OID(data
, OID_KERBEROS5
);
269 data_remaining
= asn1_tag_remaining(data
);
271 if (data_remaining
< 3) {
272 data
->has_error
= True
;
274 asn1_read(data
, tok_id
, 2);
276 *ticket
= data_blob_talloc(ctx
, NULL
, data_remaining
);
277 asn1_read(data
, ticket
->data
, ticket
->length
);
282 ret
= !data
->has_error
;
284 if (data
->has_error
) {
285 data_blob_free(ticket
);
295 generate a SPNEGO krb5 negTokenInit packet, ready for a EXTENDED_SECURITY
296 kerberos session setup
298 int spnego_gen_krb5_negTokenInit(TALLOC_CTX
*ctx
,
299 const char *principal
, int time_offset
,
301 DATA_BLOB
*session_key_krb5
, uint32 extra_ap_opts
,
305 DATA_BLOB tkt
, tkt_wrapped
;
306 const char *krb_mechs
[] = {OID_KERBEROS5_OLD
, OID_KERBEROS5
, OID_NTLMSSP
, NULL
};
308 /* get a kerberos ticket for the service and extract the session key */
309 retval
= cli_krb5_get_ticket(ctx
, principal
, time_offset
,
310 &tkt
, session_key_krb5
,
317 /* wrap that up in a nice GSS-API wrapping */
318 tkt_wrapped
= spnego_gen_krb5_wrap(ctx
, tkt
, TOK_ID_KRB_AP_REQ
);
320 /* and wrap that in a shiny SPNEGO wrapper */
321 *targ
= spnego_gen_negTokenInit(ctx
, krb_mechs
, &tkt_wrapped
, NULL
);
323 data_blob_free(&tkt_wrapped
);
324 data_blob_free(&tkt
);
331 parse a spnego NTLMSSP challenge packet giving two security blobs
333 bool spnego_parse_challenge(TALLOC_CTX
*ctx
, const DATA_BLOB blob
,
334 DATA_BLOB
*chal1
, DATA_BLOB
*chal2
)
342 data
= asn1_init(talloc_tos());
347 asn1_load(data
, blob
);
348 asn1_start_tag(data
,ASN1_CONTEXT(1));
349 asn1_start_tag(data
,ASN1_SEQUENCE(0));
351 asn1_start_tag(data
,ASN1_CONTEXT(0));
352 asn1_check_enumerated(data
,1);
355 asn1_start_tag(data
,ASN1_CONTEXT(1));
356 asn1_check_OID(data
, OID_NTLMSSP
);
359 asn1_start_tag(data
,ASN1_CONTEXT(2));
360 asn1_read_OctetString(data
, ctx
, chal1
);
363 /* the second challenge is optional (XP doesn't send it) */
364 if (asn1_tag_remaining(data
)) {
365 asn1_start_tag(data
,ASN1_CONTEXT(3));
366 asn1_read_OctetString(data
, ctx
, chal2
);
373 ret
= !data
->has_error
;
375 if (data
->has_error
) {
376 data_blob_free(chal1
);
377 data_blob_free(chal2
);
386 generate a SPNEGO auth packet. This will contain the encrypted passwords
388 DATA_BLOB
spnego_gen_auth(TALLOC_CTX
*ctx
, DATA_BLOB blob
)
393 data
= asn1_init(talloc_tos());
395 return data_blob_null
;
398 asn1_push_tag(data
, ASN1_CONTEXT(1));
399 asn1_push_tag(data
, ASN1_SEQUENCE(0));
400 asn1_push_tag(data
, ASN1_CONTEXT(2));
401 asn1_write_OctetString(data
,blob
.data
,blob
.length
);
406 ret
= data_blob_talloc(ctx
, data
->data
, data
->length
);
414 parse a SPNEGO auth packet. This contains the encrypted passwords
416 bool spnego_parse_auth_response(TALLOC_CTX
*ctx
,
417 DATA_BLOB blob
, NTSTATUS nt_status
,
424 if (NT_STATUS_IS_OK(nt_status
)) {
425 negResult
= SPNEGO_ACCEPT_COMPLETED
;
426 } else if (NT_STATUS_EQUAL(nt_status
, NT_STATUS_MORE_PROCESSING_REQUIRED
)) {
427 negResult
= SPNEGO_ACCEPT_INCOMPLETE
;
429 negResult
= SPNEGO_REJECT
;
432 data
= asn1_init(talloc_tos());
437 asn1_load(data
, blob
);
438 asn1_start_tag(data
, ASN1_CONTEXT(1));
439 asn1_start_tag(data
, ASN1_SEQUENCE(0));
440 asn1_start_tag(data
, ASN1_CONTEXT(0));
441 asn1_check_enumerated(data
, negResult
);
444 *auth
= data_blob_null
;
446 if (asn1_tag_remaining(data
)) {
447 asn1_start_tag(data
,ASN1_CONTEXT(1));
448 asn1_check_OID(data
, mechOID
);
451 if (asn1_tag_remaining(data
)) {
452 asn1_start_tag(data
,ASN1_CONTEXT(2));
453 asn1_read_OctetString(data
, ctx
, auth
);
456 } else if (negResult
== SPNEGO_ACCEPT_INCOMPLETE
) {
460 /* Binding against Win2K DC returns a duplicate of the responseToken in
461 * the optional mechListMIC field. This is a bug in Win2K. We ignore
462 * this field if it exists. Win2K8 may return a proper mechListMIC at
463 * which point we need to implement the integrity checking. */
464 if (asn1_tag_remaining(data
)) {
465 DATA_BLOB mechList
= data_blob_null
;
466 asn1_start_tag(data
, ASN1_CONTEXT(3));
467 asn1_read_OctetString(data
, ctx
, &mechList
);
469 data_blob_free(&mechList
);
470 DEBUG(5,("spnego_parse_auth_response received mechListMIC, "
477 if (data
->has_error
) {
478 DEBUG(3,("spnego_parse_auth_response failed at %d\n", (int)data
->ofs
));
480 data_blob_free(auth
);