source: branches/samba-3.5.x/source4/auth/ntlmssp/ntlmssp_sign.c

Last change on this file was 414, checked in by Herwig Bauernfeind, 16 years ago

Samba 3.5.0: Initial import
File size: 20.2 KB
Line 
1/*
2 * Unix SMB/CIFS implementation.
3 * Version 3.0
4 * NTLMSSP Signing routines
5 * Copyright (C) Luke Kenneth Casson Leighton 1996-2001
6 * Copyright (C) Andrew Bartlett <abartlet@samba.org> 2003-2005
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 3 of the License, or
11 * (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, see <http://www.gnu.org/licenses/>.
20 */
21
22#include "includes.h"
23#include "auth/ntlmssp/ntlmssp.h"
24#include "../librpc/gen_ndr/ntlmssp.h"
25#include "../libcli/auth/libcli_auth.h"
26#include "../lib/crypto/crypto.h"
27#include "auth/gensec/gensec.h"
28
29#define CLI_SIGN "session key to client-to-server signing key magic constant"
30#define CLI_SEAL "session key to client-to-server sealing key magic constant"
31#define SRV_SIGN "session key to server-to-client signing key magic constant"
32#define SRV_SEAL "session key to server-to-client sealing key magic constant"
33
34/**
35 * Some notes on the NTLM2 code:
36 *
37 * NTLM2 is a AEAD system. This means that the data encrypted is not
38 * all the data that is signed. In DCE-RPC case, the headers of the
39 * DCE-RPC packets are also signed. This prevents some of the
40 * fun-and-games one might have by changing them.
41 *
42 */
43
44static void calc_ntlmv2_key(TALLOC_CTX *mem_ctx,
45 DATA_BLOB *subkey,
46 DATA_BLOB session_key,
47 const char *constant)
48{
49 struct MD5Context ctx3;
50 *subkey = data_blob_talloc(mem_ctx, NULL, 16);
51 MD5Init(&ctx3);
52 MD5Update(&ctx3, session_key.data, session_key.length);
53 MD5Update(&ctx3, (const uint8_t *)constant, strlen(constant)+1);
54 MD5Final(subkey->data, &ctx3);
55}
56
57enum ntlmssp_direction {
58 NTLMSSP_SEND,
59 NTLMSSP_RECEIVE
60};
61
62static NTSTATUS ntlmssp_make_packet_signature(struct gensec_ntlmssp_state *gensec_ntlmssp_state,
63 TALLOC_CTX *sig_mem_ctx,
64 const uint8_t *data, size_t length,
65 const uint8_t *whole_pdu, size_t pdu_length,
66 enum ntlmssp_direction direction,
67 DATA_BLOB *sig, bool encrypt_sig)
68{
69 if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2) {
70
71 HMACMD5Context ctx;
72 uint8_t digest[16];
73 uint8_t seq_num[4];
74
75 *sig = data_blob_talloc(sig_mem_ctx, NULL, NTLMSSP_SIG_SIZE);
76 if (!sig->data) {
77 return NT_STATUS_NO_MEMORY;
78 }
79
80 switch (direction) {
81 case NTLMSSP_SEND:
82 SIVAL(seq_num, 0, gensec_ntlmssp_state->crypt.ntlm2.send_seq_num);
83 gensec_ntlmssp_state->crypt.ntlm2.send_seq_num++;
84 hmac_md5_init_limK_to_64(gensec_ntlmssp_state->crypt.ntlm2.send_sign_key.data,
85 gensec_ntlmssp_state->crypt.ntlm2.send_sign_key.length, &ctx);
86 break;
87 case NTLMSSP_RECEIVE:
88 SIVAL(seq_num, 0, gensec_ntlmssp_state->crypt.ntlm2.recv_seq_num);
89 gensec_ntlmssp_state->crypt.ntlm2.recv_seq_num++;
90 hmac_md5_init_limK_to_64(gensec_ntlmssp_state->crypt.ntlm2.recv_sign_key.data,
91 gensec_ntlmssp_state->crypt.ntlm2.recv_sign_key.length, &ctx);
92 break;
93 }
94 hmac_md5_update(seq_num, sizeof(seq_num), &ctx);
95 hmac_md5_update(whole_pdu, pdu_length, &ctx);
96 hmac_md5_final(digest, &ctx);
97
98 if (encrypt_sig && gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_KEY_EXCH) {
99 switch (direction) {
100 case NTLMSSP_SEND:
101 arcfour_crypt_sbox(gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state, digest, 8);
102 break;
103 case NTLMSSP_RECEIVE:
104 arcfour_crypt_sbox(gensec_ntlmssp_state->crypt.ntlm2.recv_seal_arcfour_state, digest, 8);
105 break;
106 }
107 }
108
109 SIVAL(sig->data, 0, NTLMSSP_SIGN_VERSION);
110 memcpy(sig->data + 4, digest, 8);
111 memcpy(sig->data + 12, seq_num, 4);
112
113 DEBUG(10, ("NTLM2: created signature over %llu bytes of input:\n", (unsigned long long)pdu_length));
114 dump_data(11, sig->data, sig->length);
115
116 } else {
117 uint32_t crc;
118 crc = crc32_calc_buffer(data, length);
119 if (!msrpc_gen(sig_mem_ctx,
120 sig, "dddd", NTLMSSP_SIGN_VERSION, 0, crc, gensec_ntlmssp_state->crypt.ntlm.seq_num)) {
121 return NT_STATUS_NO_MEMORY;
122 }
123 gensec_ntlmssp_state->crypt.ntlm.seq_num++;
124
125 arcfour_crypt_sbox(gensec_ntlmssp_state->crypt.ntlm.arcfour_state, sig->data+4, sig->length-4);
126
127 DEBUG(10, ("NTLM1: created signature over %llu bytes of input:\n", (unsigned long long)length));
128 dump_data(11, sig->data, sig->length);
129 }
130 return NT_STATUS_OK;
131}
132
133/* TODO: make this non-public */
134NTSTATUS gensec_ntlmssp_sign_packet(struct gensec_security *gensec_security,
135 TALLOC_CTX *sig_mem_ctx,
136 const uint8_t *data, size_t length,
137 const uint8_t *whole_pdu, size_t pdu_length,
138 DATA_BLOB *sig)
139{
140 struct gensec_ntlmssp_state *gensec_ntlmssp_state = (struct gensec_ntlmssp_state *)gensec_security->private_data;
141
142 return ntlmssp_make_packet_signature(gensec_ntlmssp_state, sig_mem_ctx,
143 data, length,
144 whole_pdu, pdu_length,
145 NTLMSSP_SEND, sig, true);
146}
147
148/**
149 * Check the signature of an incoming packet
150 *
151 */
152
153NTSTATUS gensec_ntlmssp_check_packet(struct gensec_security *gensec_security,
154 TALLOC_CTX *sig_mem_ctx,
155 const uint8_t *data, size_t length,
156 const uint8_t *whole_pdu, size_t pdu_length,
157 const DATA_BLOB *sig)
158{
159 struct gensec_ntlmssp_state *gensec_ntlmssp_state = (struct gensec_ntlmssp_state *)gensec_security->private_data;
160
161 DATA_BLOB local_sig;
162 NTSTATUS nt_status;
163
164 if (!gensec_ntlmssp_state->session_key.length) {
165 DEBUG(3, ("NO session key, cannot check packet signature\n"));
166 return NT_STATUS_NO_USER_SESSION_KEY;
167 }
168
169 nt_status = ntlmssp_make_packet_signature(gensec_ntlmssp_state, sig_mem_ctx,
170 data, length,
171 whole_pdu, pdu_length,
172 NTLMSSP_RECEIVE, &local_sig, true);
173
174 if (!NT_STATUS_IS_OK(nt_status)) {
175 DEBUG(0, ("NTLMSSP packet check failed with %s\n", nt_errstr(nt_status)));
176 return nt_status;
177 }
178
179 if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2) {
180 if (local_sig.length != sig->length ||
181 memcmp(local_sig.data,
182 sig->data, sig->length) != 0) {
183 DEBUG(5, ("BAD SIG NTLM2: wanted signature over %llu bytes of input:\n", (unsigned long long)pdu_length));
184 dump_data(5, local_sig.data, local_sig.length);
185
186 DEBUG(5, ("BAD SIG: got signature over %llu bytes of input:\n", (unsigned long long)pdu_length));
187 dump_data(5, sig->data, sig->length);
188
189 DEBUG(1, ("NTLMSSP NTLM2 packet check failed due to invalid signature on %llu bytes of input!\n", (unsigned long long)pdu_length));
190 return NT_STATUS_ACCESS_DENIED;
191 }
192 } else {
193 if (local_sig.length != sig->length ||
194 memcmp(local_sig.data + 8,
195 sig->data + 8, sig->length - 8) != 0) {
196 DEBUG(5, ("BAD SIG NTLM1: wanted signature of %llu bytes of input:\n", (unsigned long long)length));
197 dump_data(5, local_sig.data, local_sig.length);
198
199 DEBUG(5, ("BAD SIG: got signature of %llu bytes of input:\n", (unsigned long long)length));
200 dump_data(5, sig->data, sig->length);
201
202 DEBUG(1, ("NTLMSSP NTLM1 packet check failed due to invalid signature on %llu bytes of input:\n", (unsigned long long)length));
203 return NT_STATUS_ACCESS_DENIED;
204 }
205 }
206 dump_data_pw("checked ntlmssp signature\n", sig->data, sig->length);
207
208 return NT_STATUS_OK;
209}
210
211
212/**
213 * Seal data with the NTLMSSP algorithm
214 *
215 */
216
217NTSTATUS gensec_ntlmssp_seal_packet(struct gensec_security *gensec_security,
218 TALLOC_CTX *sig_mem_ctx,
219 uint8_t *data, size_t length,
220 const uint8_t *whole_pdu, size_t pdu_length,
221 DATA_BLOB *sig)
222{
223 struct gensec_ntlmssp_state *gensec_ntlmssp_state = (struct gensec_ntlmssp_state *)gensec_security->private_data;
224 NTSTATUS nt_status;
225 if (!gensec_ntlmssp_state->session_key.length) {
226 DEBUG(3, ("NO session key, cannot seal packet\n"));
227 return NT_STATUS_NO_USER_SESSION_KEY;
228 }
229
230 DEBUG(10,("ntlmssp_seal_data: seal\n"));
231 dump_data_pw("ntlmssp clear data\n", data, length);
232 if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2) {
233 /* The order of these two operations matters - we must first seal the packet,
234 then seal the sequence number - this is becouse the send_seal_hash is not
235 constant, but is is rather updated with each iteration */
236 nt_status = ntlmssp_make_packet_signature(gensec_ntlmssp_state, sig_mem_ctx,
237 data, length,
238 whole_pdu, pdu_length,
239 NTLMSSP_SEND, sig, false);
240 arcfour_crypt_sbox(gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state, data, length);
241 if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_KEY_EXCH) {
242 arcfour_crypt_sbox(gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state, sig->data+4, 8);
243 }
244 } else {
245 uint32_t crc;
246 crc = crc32_calc_buffer(data, length);
247 if (!msrpc_gen(sig_mem_ctx,
248 sig, "dddd", NTLMSSP_SIGN_VERSION, 0, crc, gensec_ntlmssp_state->crypt.ntlm.seq_num)) {
249 return NT_STATUS_NO_MEMORY;
250 }
251
252 /* The order of these two operations matters - we must
253 first seal the packet, then seal the sequence
254 number - this is becouse the ntlmssp_hash is not
255 constant, but is is rather updated with each
256 iteration */
257
258 arcfour_crypt_sbox(gensec_ntlmssp_state->crypt.ntlm.arcfour_state, data, length);
259 arcfour_crypt_sbox(gensec_ntlmssp_state->crypt.ntlm.arcfour_state, sig->data+4, sig->length-4);
260 /* increment counter on send */
261 gensec_ntlmssp_state->crypt.ntlm.seq_num++;
262 nt_status = NT_STATUS_OK;
263 }
264 dump_data_pw("ntlmssp signature\n", sig->data, sig->length);
265 dump_data_pw("ntlmssp sealed data\n", data, length);
266
267
268 return nt_status;
269}
270
271/**
272 * Unseal data with the NTLMSSP algorithm
273 *
274 */
275
276/*
277 wrappers for the ntlmssp_*() functions
278*/
279NTSTATUS gensec_ntlmssp_unseal_packet(struct gensec_security *gensec_security,
280 TALLOC_CTX *sig_mem_ctx,
281 uint8_t *data, size_t length,
282 const uint8_t *whole_pdu, size_t pdu_length,
283 const DATA_BLOB *sig)
284{
285 struct gensec_ntlmssp_state *gensec_ntlmssp_state = (struct gensec_ntlmssp_state *)gensec_security->private_data;
286 if (!gensec_ntlmssp_state->session_key.length) {
287 DEBUG(3, ("NO session key, cannot unseal packet\n"));
288 return NT_STATUS_NO_USER_SESSION_KEY;
289 }
290
291 dump_data_pw("ntlmssp sealed data\n", data, length);
292 if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2) {
293 arcfour_crypt_sbox(gensec_ntlmssp_state->crypt.ntlm2.recv_seal_arcfour_state, data, length);
294 } else {
295 arcfour_crypt_sbox(gensec_ntlmssp_state->crypt.ntlm.arcfour_state, data, length);
296 }
297 dump_data_pw("ntlmssp clear data\n", data, length);
298 return gensec_ntlmssp_check_packet(gensec_security, sig_mem_ctx, data, length, whole_pdu, pdu_length, sig);
299}
300
301/**
302 Initialise the state for NTLMSSP signing.
303*/
304/* TODO: make this non-public */
305NTSTATUS ntlmssp_sign_init(struct gensec_ntlmssp_state *gensec_ntlmssp_state)
306{
307 TALLOC_CTX *mem_ctx = talloc_new(gensec_ntlmssp_state);
308
309 if (!mem_ctx) {
310 return NT_STATUS_NO_MEMORY;
311 }
312
313 DEBUG(3, ("NTLMSSP Sign/Seal - Initialising with flags:\n"));
314 debug_ntlmssp_flags(gensec_ntlmssp_state->neg_flags);
315
316 if (gensec_ntlmssp_state->session_key.length < 8) {
317 talloc_free(mem_ctx);
318 DEBUG(3, ("NO session key, cannot intialise signing\n"));
319 return NT_STATUS_NO_USER_SESSION_KEY;
320 }
321
322 if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2)
323 {
324 DATA_BLOB weak_session_key = gensec_ntlmssp_state->session_key;
325 const char *send_sign_const;
326 const char *send_seal_const;
327 const char *recv_sign_const;
328 const char *recv_seal_const;
329
330 DATA_BLOB send_seal_key;
331 DATA_BLOB recv_seal_key;
332
333 switch (gensec_ntlmssp_state->role) {
334 case NTLMSSP_CLIENT:
335 send_sign_const = CLI_SIGN;
336 send_seal_const = CLI_SEAL;
337 recv_sign_const = SRV_SIGN;
338 recv_seal_const = SRV_SEAL;
339 break;
340 case NTLMSSP_SERVER:
341 send_sign_const = SRV_SIGN;
342 send_seal_const = SRV_SEAL;
343 recv_sign_const = CLI_SIGN;
344 recv_seal_const = CLI_SEAL;
345 break;
346 default:
347 talloc_free(mem_ctx);
348 return NT_STATUS_INTERNAL_ERROR;
349 }
350
351 gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state = talloc(gensec_ntlmssp_state, struct arcfour_state);
352 NT_STATUS_HAVE_NO_MEMORY(gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state);
353 gensec_ntlmssp_state->crypt.ntlm2.recv_seal_arcfour_state = talloc(gensec_ntlmssp_state, struct arcfour_state);
354 NT_STATUS_HAVE_NO_MEMORY(gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state);
355
356 /**
357 Weaken NTLMSSP keys to cope with down-level
358 clients, servers and export restrictions.
359
360 We probably should have some parameters to control
361 this, once we get NTLM2 working.
362 */
363
364 /* Key weakening was not performed on the master key
365 * for NTLM2 (in ntlmssp_weaken_keys()), but must be
366 * done on the encryption subkeys only. That is why
367 * we don't have this code for the ntlmv1 case.
368 */
369
370 if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_128) {
371
372 } else if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_56) {
373 weak_session_key.length = 7;
374 } else { /* forty bits */
375 weak_session_key.length = 5;
376 }
377 dump_data_pw("NTLMSSP weakend master key:\n",
378 weak_session_key.data,
379 weak_session_key.length);
380
381 /* SEND: sign key */
382 calc_ntlmv2_key(gensec_ntlmssp_state,
383 &gensec_ntlmssp_state->crypt.ntlm2.send_sign_key,
384 gensec_ntlmssp_state->session_key, send_sign_const);
385 dump_data_pw("NTLMSSP send sign key:\n",
386 gensec_ntlmssp_state->crypt.ntlm2.send_sign_key.data,
387 gensec_ntlmssp_state->crypt.ntlm2.send_sign_key.length);
388
389 /* SEND: seal ARCFOUR pad */
390 calc_ntlmv2_key(mem_ctx,
391 &send_seal_key,
392 weak_session_key, send_seal_const);
393 dump_data_pw("NTLMSSP send seal key:\n",
394 send_seal_key.data,
395 send_seal_key.length);
396 arcfour_init(gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state,
397 &send_seal_key);
398 dump_data_pw("NTLMSSP send sesl hash:\n",
399 gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state->sbox,
400 sizeof(gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state->sbox));
401
402 /* RECV: sign key */
403 calc_ntlmv2_key(gensec_ntlmssp_state,
404 &gensec_ntlmssp_state->crypt.ntlm2.recv_sign_key,
405 gensec_ntlmssp_state->session_key, recv_sign_const);
406 dump_data_pw("NTLMSSP recv sign key:\n",
407 gensec_ntlmssp_state->crypt.ntlm2.recv_sign_key.data,
408 gensec_ntlmssp_state->crypt.ntlm2.recv_sign_key.length);
409
410 /* RECV: seal ARCFOUR pad */
411 calc_ntlmv2_key(mem_ctx,
412 &recv_seal_key,
413 weak_session_key, recv_seal_const);
414 dump_data_pw("NTLMSSP recv seal key:\n",
415 recv_seal_key.data,
416 recv_seal_key.length);
417 arcfour_init(gensec_ntlmssp_state->crypt.ntlm2.recv_seal_arcfour_state,
418 &recv_seal_key);
419 dump_data_pw("NTLMSSP receive seal hash:\n",
420 gensec_ntlmssp_state->crypt.ntlm2.recv_seal_arcfour_state->sbox,
421 sizeof(gensec_ntlmssp_state->crypt.ntlm2.recv_seal_arcfour_state->sbox));
422
423 gensec_ntlmssp_state->crypt.ntlm2.send_seq_num = 0;
424 gensec_ntlmssp_state->crypt.ntlm2.recv_seq_num = 0;
425
426 } else {
427 DATA_BLOB weak_session_key = ntlmssp_weakend_key(gensec_ntlmssp_state, mem_ctx);
428 DEBUG(5, ("NTLMSSP Sign/Seal - using NTLM1\n"));
429
430 gensec_ntlmssp_state->crypt.ntlm.arcfour_state = talloc(gensec_ntlmssp_state, struct arcfour_state);
431 NT_STATUS_HAVE_NO_MEMORY(gensec_ntlmssp_state->crypt.ntlm.arcfour_state);
432
433 arcfour_init(gensec_ntlmssp_state->crypt.ntlm.arcfour_state,
434 &weak_session_key);
435 dump_data_pw("NTLMSSP hash:\n", gensec_ntlmssp_state->crypt.ntlm.arcfour_state->sbox,
436 sizeof(gensec_ntlmssp_state->crypt.ntlm.arcfour_state->sbox));
437
438 gensec_ntlmssp_state->crypt.ntlm.seq_num = 0;
439 }
440
441 talloc_free(mem_ctx);
442 return NT_STATUS_OK;
443}
444
445size_t gensec_ntlmssp_sig_size(struct gensec_security *gensec_security, size_t data_size)
446{
447 return NTLMSSP_SIG_SIZE;
448}
449
450NTSTATUS gensec_ntlmssp_wrap(struct gensec_security *gensec_security,
451 TALLOC_CTX *sig_mem_ctx,
452 const DATA_BLOB *in,
453 DATA_BLOB *out)
454{
455 DATA_BLOB sig;
456 NTSTATUS nt_status;
457
458 if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
459
460 *out = data_blob_talloc(sig_mem_ctx, NULL, in->length + NTLMSSP_SIG_SIZE);
461 if (!out->data) {
462 return NT_STATUS_NO_MEMORY;
463 }
464 memcpy(out->data + NTLMSSP_SIG_SIZE, in->data, in->length);
465
466 nt_status = gensec_ntlmssp_seal_packet(gensec_security, sig_mem_ctx,
467 out->data + NTLMSSP_SIG_SIZE,
468 out->length - NTLMSSP_SIG_SIZE,
469 out->data + NTLMSSP_SIG_SIZE,
470 out->length - NTLMSSP_SIG_SIZE,
471 &sig);
472
473 if (NT_STATUS_IS_OK(nt_status)) {
474 memcpy(out->data, sig.data, NTLMSSP_SIG_SIZE);
475 }
476 return nt_status;
477
478 } else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
479
480 *out = data_blob_talloc(sig_mem_ctx, NULL, in->length + NTLMSSP_SIG_SIZE);
481 if (!out->data) {
482 return NT_STATUS_NO_MEMORY;
483 }
484 memcpy(out->data + NTLMSSP_SIG_SIZE, in->data, in->length);
485
486 nt_status = gensec_ntlmssp_sign_packet(gensec_security, sig_mem_ctx,
487 out->data + NTLMSSP_SIG_SIZE,
488 out->length - NTLMSSP_SIG_SIZE,
489 out->data + NTLMSSP_SIG_SIZE,
490 out->length - NTLMSSP_SIG_SIZE,
491 &sig);
492
493 if (NT_STATUS_IS_OK(nt_status)) {
494 memcpy(out->data, sig.data, NTLMSSP_SIG_SIZE);
495 }
496 return nt_status;
497
498 } else {
499 *out = *in;
500 return NT_STATUS_OK;
501 }
502}
503
504
505NTSTATUS gensec_ntlmssp_unwrap(struct gensec_security *gensec_security,
506 TALLOC_CTX *sig_mem_ctx,
507 const DATA_BLOB *in,
508 DATA_BLOB *out)
509{
510 DATA_BLOB sig;
511
512 if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
513 if (in->length < NTLMSSP_SIG_SIZE) {
514 return NT_STATUS_INVALID_PARAMETER;
515 }
516 sig.data = in->data;
517 sig.length = NTLMSSP_SIG_SIZE;
518
519 *out = data_blob_talloc(sig_mem_ctx, in->data + NTLMSSP_SIG_SIZE, in->length - NTLMSSP_SIG_SIZE);
520
521 return gensec_ntlmssp_unseal_packet(gensec_security, sig_mem_ctx,
522 out->data, out->length,
523 out->data, out->length,
524 &sig);
525
526 } else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
527 struct gensec_ntlmssp_state *gensec_ntlmssp_state =
528 (struct gensec_ntlmssp_state *)gensec_security->private_data;
529 NTSTATUS status;
530 uint32_t ntlm_seqnum;
531 struct arcfour_state ntlm_state;
532 uint32_t ntlm2_seqnum_r;
533 uint8_t ntlm2_key_r[16];
534 struct arcfour_state ntlm2_state_r;
535
536 if (in->length < NTLMSSP_SIG_SIZE) {
537 return NT_STATUS_INVALID_PARAMETER;
538 }
539 sig.data = in->data;
540 sig.length = NTLMSSP_SIG_SIZE;
541 *out = data_blob_talloc(sig_mem_ctx, in->data + NTLMSSP_SIG_SIZE, in->length - NTLMSSP_SIG_SIZE);
542
543 if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2) {
544 ntlm2_seqnum_r = gensec_ntlmssp_state->crypt.ntlm2.recv_seq_num;
545 ntlm2_state_r = *gensec_ntlmssp_state->crypt.ntlm2.recv_seal_arcfour_state;
546 memcpy(ntlm2_key_r,
547 gensec_ntlmssp_state->crypt.ntlm2.recv_sign_key.data,
548 16);
549 } else {
550 ntlm_seqnum = gensec_ntlmssp_state->crypt.ntlm.seq_num;
551 ntlm_state = *gensec_ntlmssp_state->crypt.ntlm.arcfour_state;
552 }
553
554 status = gensec_ntlmssp_check_packet(gensec_security, sig_mem_ctx,
555 out->data, out->length,
556 out->data, out->length,
557 &sig);
558 if (!NT_STATUS_IS_OK(status)) {
559 NTSTATUS check_status = status;
560 /*
561 * The Windows LDAP libraries seems to have a bug
562 * and always use sealing even if only signing was
563 * negotiated. So we need to fallback.
564 */
565
566 if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2) {
567 gensec_ntlmssp_state->crypt.ntlm2.recv_seq_num = ntlm2_seqnum_r;
568 *gensec_ntlmssp_state->crypt.ntlm2.recv_seal_arcfour_state = ntlm2_state_r;
569 memcpy(gensec_ntlmssp_state->crypt.ntlm2.recv_sign_key.data,
570 ntlm2_key_r, 16);
571 } else {
572 gensec_ntlmssp_state->crypt.ntlm.seq_num = ntlm_seqnum;
573 *gensec_ntlmssp_state->crypt.ntlm.arcfour_state = ntlm_state;
574 }
575
576 status = gensec_ntlmssp_unseal_packet(gensec_security,
577 sig_mem_ctx,
578 out->data,
579 out->length,
580 out->data,
581 out->length,
582 &sig);
583 if (NT_STATUS_IS_OK(status)) {
584 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_SEAL;
585 } else {
586 status = check_status;
587 }
588 }
589 return status;
590 } else {
591 *out = *in;
592 return NT_STATUS_OK;
593 }
594}
595
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