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 for (i = 0; i < ASN1_MAX_OIDS; i++) {
110 data = asn1_init(talloc_tos());
115 asn1_load(data, blob);
117 asn1_start_tag(data,ASN1_APPLICATION(0));
119 asn1_check_OID(data,OID_SPNEGO);
121 /* negTokenInit [0] NegTokenInit */
122 asn1_start_tag(data,ASN1_CONTEXT(0));
123 asn1_start_tag(data,ASN1_SEQUENCE(0));
125 /* mechTypes [0] MechTypeList OPTIONAL */
127 /* Not really optional, we depend on this to decide
128 * what mechanisms we have to work with. */
130 asn1_start_tag(data,ASN1_CONTEXT(0));
131 asn1_start_tag(data,ASN1_SEQUENCE(0));
132 for (i=0; asn1_tag_remaining(data) > 0 && i < ASN1_MAX_OIDS-1; i++) {
133 if (!asn1_read_OID(data,ctx, &OIDs[i])) {
136 if (data->has_error) {
148 *secblob = data_blob_null;
152 Win7 + Live Sign-in Assistant attaches a mechToken
153 ASN1_CONTEXT(2) to the negTokenInit packet
154 which breaks our negotiation if we just assume
155 the next tag is ASN1_CONTEXT(3).
158 if (asn1_peek_tag(data, ASN1_CONTEXT(1))) {
161 /* reqFlags [1] ContextFlags OPTIONAL */
162 asn1_start_tag(data, ASN1_CONTEXT(1));
163 asn1_start_tag(data, ASN1_BIT_STRING);
164 while (asn1_tag_remaining(data) > 0) {
165 asn1_read_uint8(data, &flags);
171 if (asn1_peek_tag(data, ASN1_CONTEXT(2))) {
172 DATA_BLOB sblob = data_blob_null;
173 /* mechToken [2] OCTET STRING OPTIONAL */
174 asn1_start_tag(data, ASN1_CONTEXT(2));
175 asn1_read_OctetString(data, ctx, &sblob);
180 data_blob_free(&sblob);
184 if (asn1_peek_tag(data, ASN1_CONTEXT(3))) {
186 /* mechListMIC [3] OCTET STRING OPTIONAL */
187 asn1_start_tag(data, ASN1_CONTEXT(3));
188 asn1_start_tag(data, ASN1_SEQUENCE(0));
189 asn1_start_tag(data, ASN1_CONTEXT(0));
190 asn1_read_GeneralString(data, ctx, &princ);
206 ret = !data->has_error;
207 if (data->has_error) {
210 TALLOC_FREE(*principal);
213 data_blob_free(secblob);
215 for(j = 0; j < i && j < ASN1_MAX_OIDS-1; j++) {
216 TALLOC_FREE(OIDs[j]);
225 generate a krb5 GSS-API wrapper packet given a ticket
227 DATA_BLOB spnego_gen_krb5_wrap(TALLOC_CTX *ctx, const DATA_BLOB ticket, const uint8 tok_id[2])
232 data = asn1_init(talloc_tos());
234 return data_blob_null;
237 asn1_push_tag(data, ASN1_APPLICATION(0));
238 asn1_write_OID(data, OID_KERBEROS5);
240 asn1_write(data, tok_id, 2);
241 asn1_write(data, ticket.data, ticket.length);
244 if (data->has_error) {
245 DEBUG(1,("Failed to build krb5 wrapper at offset %d\n", (int)data->ofs));
248 ret = data_blob_talloc(ctx, data->data, data->length);
255 generate a SPNEGO krb5 negTokenInit packet, ready for a EXTENDED_SECURITY
256 kerberos session setup
258 int spnego_gen_krb5_negTokenInit(TALLOC_CTX *ctx,
259 const char *principal, int time_offset,
261 DATA_BLOB *session_key_krb5, uint32 extra_ap_opts,
262 const char *ccname, time_t *expire_time)
265 DATA_BLOB tkt, tkt_wrapped;
266 const char *krb_mechs[] = {OID_KERBEROS5_OLD, OID_KERBEROS5, OID_NTLMSSP, NULL};
268 /* get a kerberos ticket for the service and extract the session key */
269 retval = cli_krb5_get_ticket(ctx, principal, time_offset,
270 &tkt, session_key_krb5,
271 extra_ap_opts, ccname,
277 /* wrap that up in a nice GSS-API wrapping */
278 tkt_wrapped = spnego_gen_krb5_wrap(ctx, tkt, TOK_ID_KRB_AP_REQ);
280 /* and wrap that in a shiny SPNEGO wrapper */
281 *targ = spnego_gen_negTokenInit(ctx, krb_mechs, &tkt_wrapped, NULL);
283 data_blob_free(&tkt_wrapped);
284 data_blob_free(&tkt);
291 parse a spnego NTLMSSP challenge packet giving two security blobs
293 bool spnego_parse_challenge(TALLOC_CTX *ctx, const DATA_BLOB blob,
294 DATA_BLOB *chal1, DATA_BLOB *chal2)
302 data = asn1_init(talloc_tos());
307 asn1_load(data, blob);
308 asn1_start_tag(data,ASN1_CONTEXT(1));
309 asn1_start_tag(data,ASN1_SEQUENCE(0));
311 asn1_start_tag(data,ASN1_CONTEXT(0));
312 asn1_check_enumerated(data,1);
315 asn1_start_tag(data,ASN1_CONTEXT(1));
316 asn1_check_OID(data, OID_NTLMSSP);
319 asn1_start_tag(data,ASN1_CONTEXT(2));
320 asn1_read_OctetString(data, ctx, chal1);
323 /* the second challenge is optional (XP doesn't send it) */
324 if (asn1_tag_remaining(data)) {
325 asn1_start_tag(data,ASN1_CONTEXT(3));
326 asn1_read_OctetString(data, ctx, chal2);
333 ret = !data->has_error;
335 if (data->has_error) {
336 data_blob_free(chal1);
337 data_blob_free(chal2);
346 generate a SPNEGO auth packet. This will contain the encrypted passwords
348 DATA_BLOB spnego_gen_auth(TALLOC_CTX *ctx, DATA_BLOB blob)
353 data = asn1_init(talloc_tos());
355 return data_blob_null;
358 asn1_push_tag(data, ASN1_CONTEXT(1));
359 asn1_push_tag(data, ASN1_SEQUENCE(0));
360 asn1_push_tag(data, ASN1_CONTEXT(2));
361 asn1_write_OctetString(data,blob.data,blob.length);
366 ret = data_blob_talloc(ctx, data->data, data->length);
374 parse a SPNEGO auth packet. This contains the encrypted passwords
376 bool spnego_parse_auth_response(TALLOC_CTX *ctx,
377 DATA_BLOB blob, NTSTATUS nt_status,
384 if (NT_STATUS_IS_OK(nt_status)) {
385 negResult = SPNEGO_ACCEPT_COMPLETED;
386 } else if (NT_STATUS_EQUAL(nt_status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
387 negResult = SPNEGO_ACCEPT_INCOMPLETE;
389 negResult = SPNEGO_REJECT;
392 data = asn1_init(talloc_tos());
397 asn1_load(data, blob);
398 asn1_start_tag(data, ASN1_CONTEXT(1));
399 asn1_start_tag(data, ASN1_SEQUENCE(0));
400 asn1_start_tag(data, ASN1_CONTEXT(0));
401 asn1_check_enumerated(data, negResult);
404 *auth = data_blob_null;
406 if (asn1_tag_remaining(data)) {
407 asn1_start_tag(data,ASN1_CONTEXT(1));
408 asn1_check_OID(data, mechOID);
411 if (asn1_tag_remaining(data)) {
412 asn1_start_tag(data,ASN1_CONTEXT(2));
413 asn1_read_OctetString(data, ctx, auth);
416 } else if (negResult == SPNEGO_ACCEPT_INCOMPLETE) {
420 /* Binding against Win2K DC returns a duplicate of the responseToken in
421 * the optional mechListMIC field. This is a bug in Win2K. We ignore
422 * this field if it exists. Win2K8 may return a proper mechListMIC at
423 * which point we need to implement the integrity checking. */
424 if (asn1_tag_remaining(data)) {
425 DATA_BLOB mechList = data_blob_null;
426 asn1_start_tag(data, ASN1_CONTEXT(3));
427 asn1_read_OctetString(data, ctx, &mechList);
429 data_blob_free(&mechList);
430 DEBUG(5,("spnego_parse_auth_response received mechListMIC, "
437 if (data->has_error) {
438 DEBUG(3,("spnego_parse_auth_response failed at %d\n", (int)data->ofs));
440 data_blob_free(auth);