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 generate a SPNEGO krb5 negTokenInit packet, ready for a EXTENDED_SECURITY
252 kerberos session setup
254 int spnego_gen_krb5_negTokenInit(TALLOC_CTX
*ctx
,
255 const char *principal
, int time_offset
,
257 DATA_BLOB
*session_key_krb5
, uint32 extra_ap_opts
,
258 const char *ccname
, time_t *expire_time
)
261 DATA_BLOB tkt
, tkt_wrapped
;
262 const char *krb_mechs
[] = {OID_KERBEROS5_OLD
, OID_KERBEROS5
, OID_NTLMSSP
, NULL
};
264 /* get a kerberos ticket for the service and extract the session key */
265 retval
= cli_krb5_get_ticket(ctx
, principal
, time_offset
,
266 &tkt
, session_key_krb5
,
267 extra_ap_opts
, ccname
,
273 /* wrap that up in a nice GSS-API wrapping */
274 tkt_wrapped
= spnego_gen_krb5_wrap(ctx
, tkt
, TOK_ID_KRB_AP_REQ
);
276 /* and wrap that in a shiny SPNEGO wrapper */
277 *targ
= spnego_gen_negTokenInit(ctx
, krb_mechs
, &tkt_wrapped
, NULL
);
279 data_blob_free(&tkt_wrapped
);
280 data_blob_free(&tkt
);
287 parse a spnego NTLMSSP challenge packet giving two security blobs
289 bool spnego_parse_challenge(TALLOC_CTX
*ctx
, const DATA_BLOB blob
,
290 DATA_BLOB
*chal1
, DATA_BLOB
*chal2
)
298 data
= asn1_init(talloc_tos());
303 asn1_load(data
, blob
);
304 asn1_start_tag(data
,ASN1_CONTEXT(1));
305 asn1_start_tag(data
,ASN1_SEQUENCE(0));
307 asn1_start_tag(data
,ASN1_CONTEXT(0));
308 asn1_check_enumerated(data
,1);
311 asn1_start_tag(data
,ASN1_CONTEXT(1));
312 asn1_check_OID(data
, OID_NTLMSSP
);
315 asn1_start_tag(data
,ASN1_CONTEXT(2));
316 asn1_read_OctetString(data
, ctx
, chal1
);
319 /* the second challenge is optional (XP doesn't send it) */
320 if (asn1_tag_remaining(data
)) {
321 asn1_start_tag(data
,ASN1_CONTEXT(3));
322 asn1_read_OctetString(data
, ctx
, chal2
);
329 ret
= !data
->has_error
;
331 if (data
->has_error
) {
332 data_blob_free(chal1
);
333 data_blob_free(chal2
);
342 generate a SPNEGO auth packet. This will contain the encrypted passwords
344 DATA_BLOB
spnego_gen_auth(TALLOC_CTX
*ctx
, DATA_BLOB blob
)
349 data
= asn1_init(talloc_tos());
351 return data_blob_null
;
354 asn1_push_tag(data
, ASN1_CONTEXT(1));
355 asn1_push_tag(data
, ASN1_SEQUENCE(0));
356 asn1_push_tag(data
, ASN1_CONTEXT(2));
357 asn1_write_OctetString(data
,blob
.data
,blob
.length
);
362 ret
= data_blob_talloc(ctx
, data
->data
, data
->length
);
370 parse a SPNEGO auth packet. This contains the encrypted passwords
372 bool spnego_parse_auth_response(TALLOC_CTX
*ctx
,
373 DATA_BLOB blob
, NTSTATUS nt_status
,
380 if (NT_STATUS_IS_OK(nt_status
)) {
381 negResult
= SPNEGO_ACCEPT_COMPLETED
;
382 } else if (NT_STATUS_EQUAL(nt_status
, NT_STATUS_MORE_PROCESSING_REQUIRED
)) {
383 negResult
= SPNEGO_ACCEPT_INCOMPLETE
;
385 negResult
= SPNEGO_REJECT
;
388 data
= asn1_init(talloc_tos());
393 asn1_load(data
, blob
);
394 asn1_start_tag(data
, ASN1_CONTEXT(1));
395 asn1_start_tag(data
, ASN1_SEQUENCE(0));
396 asn1_start_tag(data
, ASN1_CONTEXT(0));
397 asn1_check_enumerated(data
, negResult
);
400 *auth
= data_blob_null
;
402 if (asn1_tag_remaining(data
)) {
403 asn1_start_tag(data
,ASN1_CONTEXT(1));
404 asn1_check_OID(data
, mechOID
);
407 if (asn1_tag_remaining(data
)) {
408 asn1_start_tag(data
,ASN1_CONTEXT(2));
409 asn1_read_OctetString(data
, ctx
, auth
);
412 } else if (negResult
== SPNEGO_ACCEPT_INCOMPLETE
) {
416 /* Binding against Win2K DC returns a duplicate of the responseToken in
417 * the optional mechListMIC field. This is a bug in Win2K. We ignore
418 * this field if it exists. Win2K8 may return a proper mechListMIC at
419 * which point we need to implement the integrity checking. */
420 if (asn1_tag_remaining(data
)) {
421 DATA_BLOB mechList
= data_blob_null
;
422 asn1_start_tag(data
, ASN1_CONTEXT(3));
423 asn1_read_OctetString(data
, ctx
, &mechList
);
425 data_blob_free(&mechList
);
426 DEBUG(5,("spnego_parse_auth_response received mechListMIC, "
433 if (data
->has_error
) {
434 DEBUG(3,("spnego_parse_auth_response failed at %d\n", (int)data
->ofs
));
436 data_blob_free(auth
);