2 * Unix SMB/CIFS implementation.
4 * NTLMSSP Signing routines
5 * Copyright (C) Luke Kenneth Casson Leighton 1996-2001
6 * Copyright (C) Andrew Bartlett <abartlet@samba.org> 2003-2005
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.
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.
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/>.
23 #include "auth/ntlmssp/ntlmssp.h"
24 #include "../libcli/auth/libcli_auth.h"
25 #include "../lib/crypto/crypto.h"
26 #include "auth/gensec/gensec.h"
28 #define CLI_SIGN "session key to client-to-server signing key magic constant"
29 #define CLI_SEAL "session key to client-to-server sealing key magic constant"
30 #define SRV_SIGN "session key to server-to-client signing key magic constant"
31 #define SRV_SEAL "session key to server-to-client sealing key magic constant"
34 * Some notes on the NTLM2 code:
36 * NTLM2 is a AEAD system. This means that the data encrypted is not
37 * all the data that is signed. In DCE-RPC case, the headers of the
38 * DCE-RPC packets are also signed. This prevents some of the
39 * fun-and-games one might have by changing them.
43 static void calc_ntlmv2_key(TALLOC_CTX *mem_ctx,
45 DATA_BLOB session_key,
48 struct MD5Context ctx3;
49 *subkey = data_blob_talloc(mem_ctx, NULL, 16);
51 MD5Update(&ctx3, session_key.data, session_key.length);
52 MD5Update(&ctx3, (const uint8_t *)constant, strlen(constant)+1);
53 MD5Final(subkey->data, &ctx3);
56 enum ntlmssp_direction {
61 static NTSTATUS ntlmssp_make_packet_signature(struct gensec_ntlmssp_state *gensec_ntlmssp_state,
62 TALLOC_CTX *sig_mem_ctx,
63 const uint8_t *data, size_t length,
64 const uint8_t *whole_pdu, size_t pdu_length,
65 enum ntlmssp_direction direction,
66 DATA_BLOB *sig, bool encrypt_sig)
68 if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2) {
74 *sig = data_blob_talloc(sig_mem_ctx, NULL, NTLMSSP_SIG_SIZE);
76 return NT_STATUS_NO_MEMORY;
81 SIVAL(seq_num, 0, gensec_ntlmssp_state->crypt.ntlm2.send_seq_num);
82 gensec_ntlmssp_state->crypt.ntlm2.send_seq_num++;
83 hmac_md5_init_limK_to_64(gensec_ntlmssp_state->crypt.ntlm2.send_sign_key.data,
84 gensec_ntlmssp_state->crypt.ntlm2.send_sign_key.length, &ctx);
87 SIVAL(seq_num, 0, gensec_ntlmssp_state->crypt.ntlm2.recv_seq_num);
88 gensec_ntlmssp_state->crypt.ntlm2.recv_seq_num++;
89 hmac_md5_init_limK_to_64(gensec_ntlmssp_state->crypt.ntlm2.recv_sign_key.data,
90 gensec_ntlmssp_state->crypt.ntlm2.recv_sign_key.length, &ctx);
93 hmac_md5_update(seq_num, sizeof(seq_num), &ctx);
94 hmac_md5_update(whole_pdu, pdu_length, &ctx);
95 hmac_md5_final(digest, &ctx);
97 if (encrypt_sig && gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_KEY_EXCH) {
100 arcfour_crypt_sbox(gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state, digest, 8);
102 case NTLMSSP_RECEIVE:
103 arcfour_crypt_sbox(gensec_ntlmssp_state->crypt.ntlm2.recv_seal_arcfour_state, digest, 8);
108 SIVAL(sig->data, 0, NTLMSSP_SIGN_VERSION);
109 memcpy(sig->data + 4, digest, 8);
110 memcpy(sig->data + 12, seq_num, 4);
112 DEBUG(10, ("NTLM2: created signature over %llu bytes of input:\n", (unsigned long long)pdu_length));
113 dump_data(11, sig->data, sig->length);
117 crc = crc32_calc_buffer(data, length);
118 if (!msrpc_gen(sig_mem_ctx,
119 sig, "dddd", NTLMSSP_SIGN_VERSION, 0, crc, gensec_ntlmssp_state->crypt.ntlm.seq_num)) {
120 return NT_STATUS_NO_MEMORY;
122 gensec_ntlmssp_state->crypt.ntlm.seq_num++;
124 arcfour_crypt_sbox(gensec_ntlmssp_state->crypt.ntlm.arcfour_state, sig->data+4, sig->length-4);
126 DEBUG(10, ("NTLM1: created signature over %llu bytes of input:\n", (unsigned long long)length));
127 dump_data(11, sig->data, sig->length);
132 /* TODO: make this non-public */
133 NTSTATUS gensec_ntlmssp_sign_packet(struct gensec_security *gensec_security,
134 TALLOC_CTX *sig_mem_ctx,
135 const uint8_t *data, size_t length,
136 const uint8_t *whole_pdu, size_t pdu_length,
139 struct gensec_ntlmssp_state *gensec_ntlmssp_state = (struct gensec_ntlmssp_state *)gensec_security->private_data;
141 return ntlmssp_make_packet_signature(gensec_ntlmssp_state, sig_mem_ctx,
143 whole_pdu, pdu_length,
144 NTLMSSP_SEND, sig, true);
148 * Check the signature of an incoming packet
152 NTSTATUS gensec_ntlmssp_check_packet(struct gensec_security *gensec_security,
153 TALLOC_CTX *sig_mem_ctx,
154 const uint8_t *data, size_t length,
155 const uint8_t *whole_pdu, size_t pdu_length,
156 const DATA_BLOB *sig)
158 struct gensec_ntlmssp_state *gensec_ntlmssp_state = (struct gensec_ntlmssp_state *)gensec_security->private_data;
163 if (!gensec_ntlmssp_state->session_key.length) {
164 DEBUG(3, ("NO session key, cannot check packet signature\n"));
165 return NT_STATUS_NO_USER_SESSION_KEY;
168 nt_status = ntlmssp_make_packet_signature(gensec_ntlmssp_state, sig_mem_ctx,
170 whole_pdu, pdu_length,
171 NTLMSSP_RECEIVE, &local_sig, true);
173 if (!NT_STATUS_IS_OK(nt_status)) {
174 DEBUG(0, ("NTLMSSP packet sig creation failed with %s\n", nt_errstr(nt_status)));
178 if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2) {
179 if (local_sig.length != sig->length ||
180 memcmp(local_sig.data,
181 sig->data, sig->length) != 0) {
183 DEBUG(10, ("BAD SIG NTLM2: wanted signature over %llu bytes of input:\n", (unsigned long long)pdu_length));
184 dump_data(10, local_sig.data, local_sig.length);
186 DEBUG(10, ("BAD SIG: got signature over %llu bytes of input:\n", (unsigned long long)pdu_length));
187 dump_data(10, sig->data, sig->length);
189 return NT_STATUS_ACCESS_DENIED;
192 if (local_sig.length != sig->length ||
193 memcmp(local_sig.data + 8,
194 sig->data + 8, sig->length - 8) != 0) {
195 DEBUG(10, ("BAD SIG NTLM1: wanted signature of %llu bytes of input:\n", (unsigned long long)length));
196 dump_data(5, local_sig.data, local_sig.length);
198 DEBUG(10, ("BAD SIG: got signature of %llu bytes of input:\n", (unsigned long long)length));
199 dump_data(10, sig->data, sig->length);
201 return NT_STATUS_ACCESS_DENIED;
204 dump_data_pw("checked ntlmssp signature\n", sig->data, sig->length);
211 * Seal data with the NTLMSSP algorithm
215 NTSTATUS gensec_ntlmssp_seal_packet(struct gensec_security *gensec_security,
216 TALLOC_CTX *sig_mem_ctx,
217 uint8_t *data, size_t length,
218 const uint8_t *whole_pdu, size_t pdu_length,
221 struct gensec_ntlmssp_state *gensec_ntlmssp_state = (struct gensec_ntlmssp_state *)gensec_security->private_data;
223 if (!gensec_ntlmssp_state->session_key.length) {
224 DEBUG(3, ("NO session key, cannot seal packet\n"));
225 return NT_STATUS_NO_USER_SESSION_KEY;
228 DEBUG(10,("ntlmssp_seal_data: seal\n"));
229 dump_data_pw("ntlmssp clear data\n", data, length);
230 if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2) {
231 /* The order of these two operations matters - we must first seal the packet,
232 then seal the sequence number - this is becouse the send_seal_hash is not
233 constant, but is is rather updated with each iteration */
234 nt_status = ntlmssp_make_packet_signature(gensec_ntlmssp_state, sig_mem_ctx,
236 whole_pdu, pdu_length,
237 NTLMSSP_SEND, sig, false);
238 arcfour_crypt_sbox(gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state, data, length);
239 if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_KEY_EXCH) {
240 arcfour_crypt_sbox(gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state, sig->data+4, 8);
244 crc = crc32_calc_buffer(data, length);
245 if (!msrpc_gen(sig_mem_ctx,
246 sig, "dddd", NTLMSSP_SIGN_VERSION, 0, crc, gensec_ntlmssp_state->crypt.ntlm.seq_num)) {
247 return NT_STATUS_NO_MEMORY;
250 /* The order of these two operations matters - we must
251 first seal the packet, then seal the sequence
252 number - this is becouse the ntlmssp_hash is not
253 constant, but is is rather updated with each
256 arcfour_crypt_sbox(gensec_ntlmssp_state->crypt.ntlm.arcfour_state, data, length);
257 arcfour_crypt_sbox(gensec_ntlmssp_state->crypt.ntlm.arcfour_state, sig->data+4, sig->length-4);
258 /* increment counter on send */
259 gensec_ntlmssp_state->crypt.ntlm.seq_num++;
260 nt_status = NT_STATUS_OK;
262 dump_data_pw("ntlmssp signature\n", sig->data, sig->length);
263 dump_data_pw("ntlmssp sealed data\n", data, length);
270 * Unseal data with the NTLMSSP algorithm
275 wrappers for the ntlmssp_*() functions
277 NTSTATUS gensec_ntlmssp_unseal_packet(struct gensec_security *gensec_security,
278 TALLOC_CTX *sig_mem_ctx,
279 uint8_t *data, size_t length,
280 const uint8_t *whole_pdu, size_t pdu_length,
281 const DATA_BLOB *sig)
284 struct gensec_ntlmssp_state *gensec_ntlmssp_state = (struct gensec_ntlmssp_state *)gensec_security->private_data;
285 if (!gensec_ntlmssp_state->session_key.length) {
286 DEBUG(3, ("NO session key, cannot unseal packet\n"));
287 return NT_STATUS_NO_USER_SESSION_KEY;
290 dump_data_pw("ntlmssp sealed data\n", data, length);
291 if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2) {
292 arcfour_crypt_sbox(gensec_ntlmssp_state->crypt.ntlm2.recv_seal_arcfour_state, data, length);
294 arcfour_crypt_sbox(gensec_ntlmssp_state->crypt.ntlm.arcfour_state, data, length);
296 dump_data_pw("ntlmssp clear data\n", data, length);
297 status = gensec_ntlmssp_check_packet(gensec_security, sig_mem_ctx, data, length, whole_pdu, pdu_length, sig);
299 if (!NT_STATUS_IS_OK(status)) {
300 DEBUG(1, ("NTLMSSP packet check for unseal failed due to invalid signature on %llu bytes of input:\n", (unsigned long long)length));
306 Initialise the state for NTLMSSP signing.
308 /* TODO: make this non-public */
309 NTSTATUS ntlmssp_sign_init(struct gensec_ntlmssp_state *gensec_ntlmssp_state)
311 TALLOC_CTX *mem_ctx = talloc_new(gensec_ntlmssp_state);
314 return NT_STATUS_NO_MEMORY;
317 DEBUG(3, ("NTLMSSP Sign/Seal - Initialising with flags:\n"));
318 debug_ntlmssp_flags(gensec_ntlmssp_state->neg_flags);
320 if (gensec_ntlmssp_state->session_key.length < 8) {
321 talloc_free(mem_ctx);
322 DEBUG(3, ("NO session key, cannot intialise signing\n"));
323 return NT_STATUS_NO_USER_SESSION_KEY;
326 if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2)
328 DATA_BLOB weak_session_key = gensec_ntlmssp_state->session_key;
329 const char *send_sign_const;
330 const char *send_seal_const;
331 const char *recv_sign_const;
332 const char *recv_seal_const;
334 DATA_BLOB send_seal_key;
335 DATA_BLOB recv_seal_key;
337 switch (gensec_ntlmssp_state->role) {
339 send_sign_const = CLI_SIGN;
340 send_seal_const = CLI_SEAL;
341 recv_sign_const = SRV_SIGN;
342 recv_seal_const = SRV_SEAL;
345 send_sign_const = SRV_SIGN;
346 send_seal_const = SRV_SEAL;
347 recv_sign_const = CLI_SIGN;
348 recv_seal_const = CLI_SEAL;
351 talloc_free(mem_ctx);
352 return NT_STATUS_INTERNAL_ERROR;
355 gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state = talloc(gensec_ntlmssp_state, struct arcfour_state);
356 NT_STATUS_HAVE_NO_MEMORY(gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state);
357 gensec_ntlmssp_state->crypt.ntlm2.recv_seal_arcfour_state = talloc(gensec_ntlmssp_state, struct arcfour_state);
358 NT_STATUS_HAVE_NO_MEMORY(gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state);
361 Weaken NTLMSSP keys to cope with down-level
362 clients, servers and export restrictions.
364 We probably should have some parameters to control
365 this, once we get NTLM2 working.
368 /* Key weakening was not performed on the master key
369 * for NTLM2 (in ntlmssp_weaken_keys()), but must be
370 * done on the encryption subkeys only. That is why
371 * we don't have this code for the ntlmv1 case.
374 if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_128) {
376 } else if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_56) {
377 weak_session_key.length = 7;
378 } else { /* forty bits */
379 weak_session_key.length = 5;
381 dump_data_pw("NTLMSSP weakend master key:\n",
382 weak_session_key.data,
383 weak_session_key.length);
386 calc_ntlmv2_key(gensec_ntlmssp_state,
387 &gensec_ntlmssp_state->crypt.ntlm2.send_sign_key,
388 gensec_ntlmssp_state->session_key, send_sign_const);
389 dump_data_pw("NTLMSSP send sign key:\n",
390 gensec_ntlmssp_state->crypt.ntlm2.send_sign_key.data,
391 gensec_ntlmssp_state->crypt.ntlm2.send_sign_key.length);
393 /* SEND: seal ARCFOUR pad */
394 calc_ntlmv2_key(mem_ctx,
396 weak_session_key, send_seal_const);
397 dump_data_pw("NTLMSSP send seal key:\n",
399 send_seal_key.length);
400 arcfour_init(gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state,
402 dump_data_pw("NTLMSSP send sesl hash:\n",
403 gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state->sbox,
404 sizeof(gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state->sbox));
407 calc_ntlmv2_key(gensec_ntlmssp_state,
408 &gensec_ntlmssp_state->crypt.ntlm2.recv_sign_key,
409 gensec_ntlmssp_state->session_key, recv_sign_const);
410 dump_data_pw("NTLMSSP recv sign key:\n",
411 gensec_ntlmssp_state->crypt.ntlm2.recv_sign_key.data,
412 gensec_ntlmssp_state->crypt.ntlm2.recv_sign_key.length);
414 /* RECV: seal ARCFOUR pad */
415 calc_ntlmv2_key(mem_ctx,
417 weak_session_key, recv_seal_const);
418 dump_data_pw("NTLMSSP recv seal key:\n",
420 recv_seal_key.length);
421 arcfour_init(gensec_ntlmssp_state->crypt.ntlm2.recv_seal_arcfour_state,
423 dump_data_pw("NTLMSSP receive seal hash:\n",
424 gensec_ntlmssp_state->crypt.ntlm2.recv_seal_arcfour_state->sbox,
425 sizeof(gensec_ntlmssp_state->crypt.ntlm2.recv_seal_arcfour_state->sbox));
427 gensec_ntlmssp_state->crypt.ntlm2.send_seq_num = 0;
428 gensec_ntlmssp_state->crypt.ntlm2.recv_seq_num = 0;
431 DATA_BLOB weak_session_key = ntlmssp_weakend_key(gensec_ntlmssp_state, mem_ctx);
432 DEBUG(5, ("NTLMSSP Sign/Seal - using NTLM1\n"));
434 gensec_ntlmssp_state->crypt.ntlm.arcfour_state = talloc(gensec_ntlmssp_state, struct arcfour_state);
435 NT_STATUS_HAVE_NO_MEMORY(gensec_ntlmssp_state->crypt.ntlm.arcfour_state);
437 arcfour_init(gensec_ntlmssp_state->crypt.ntlm.arcfour_state,
439 dump_data_pw("NTLMSSP hash:\n", gensec_ntlmssp_state->crypt.ntlm.arcfour_state->sbox,
440 sizeof(gensec_ntlmssp_state->crypt.ntlm.arcfour_state->sbox));
442 gensec_ntlmssp_state->crypt.ntlm.seq_num = 0;
445 talloc_free(mem_ctx);
449 size_t gensec_ntlmssp_sig_size(struct gensec_security *gensec_security, size_t data_size)
451 return NTLMSSP_SIG_SIZE;
454 NTSTATUS gensec_ntlmssp_wrap(struct gensec_security *gensec_security,
455 TALLOC_CTX *sig_mem_ctx,
462 if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
464 *out = data_blob_talloc(sig_mem_ctx, NULL, in->length + NTLMSSP_SIG_SIZE);
466 return NT_STATUS_NO_MEMORY;
468 memcpy(out->data + NTLMSSP_SIG_SIZE, in->data, in->length);
470 nt_status = gensec_ntlmssp_seal_packet(gensec_security, sig_mem_ctx,
471 out->data + NTLMSSP_SIG_SIZE,
472 out->length - NTLMSSP_SIG_SIZE,
473 out->data + NTLMSSP_SIG_SIZE,
474 out->length - NTLMSSP_SIG_SIZE,
477 if (NT_STATUS_IS_OK(nt_status)) {
478 memcpy(out->data, sig.data, NTLMSSP_SIG_SIZE);
482 } else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
484 *out = data_blob_talloc(sig_mem_ctx, NULL, in->length + NTLMSSP_SIG_SIZE);
486 return NT_STATUS_NO_MEMORY;
488 memcpy(out->data + NTLMSSP_SIG_SIZE, in->data, in->length);
490 nt_status = gensec_ntlmssp_sign_packet(gensec_security, sig_mem_ctx,
491 out->data + NTLMSSP_SIG_SIZE,
492 out->length - NTLMSSP_SIG_SIZE,
493 out->data + NTLMSSP_SIG_SIZE,
494 out->length - NTLMSSP_SIG_SIZE,
497 if (NT_STATUS_IS_OK(nt_status)) {
498 memcpy(out->data, sig.data, NTLMSSP_SIG_SIZE);
509 NTSTATUS gensec_ntlmssp_unwrap(struct gensec_security *gensec_security,
510 TALLOC_CTX *sig_mem_ctx,
516 if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
517 if (in->length < NTLMSSP_SIG_SIZE) {
518 return NT_STATUS_INVALID_PARAMETER;
521 sig.length = NTLMSSP_SIG_SIZE;
523 *out = data_blob_talloc(sig_mem_ctx, in->data + NTLMSSP_SIG_SIZE, in->length - NTLMSSP_SIG_SIZE);
525 return gensec_ntlmssp_unseal_packet(gensec_security, sig_mem_ctx,
526 out->data, out->length,
527 out->data, out->length,
530 } else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
531 struct gensec_ntlmssp_state *gensec_ntlmssp_state =
532 (struct gensec_ntlmssp_state *)gensec_security->private_data;
534 uint32_t ntlm_seqnum;
535 struct arcfour_state ntlm_state;
536 uint32_t ntlm2_seqnum_r;
537 uint8_t ntlm2_key_r[16];
538 struct arcfour_state ntlm2_state_r;
540 if (in->length < NTLMSSP_SIG_SIZE) {
541 return NT_STATUS_INVALID_PARAMETER;
544 sig.length = NTLMSSP_SIG_SIZE;
545 *out = data_blob_talloc(sig_mem_ctx, in->data + NTLMSSP_SIG_SIZE, in->length - NTLMSSP_SIG_SIZE);
547 if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2) {
548 ntlm2_seqnum_r = gensec_ntlmssp_state->crypt.ntlm2.recv_seq_num;
549 ntlm2_state_r = *gensec_ntlmssp_state->crypt.ntlm2.recv_seal_arcfour_state;
551 gensec_ntlmssp_state->crypt.ntlm2.recv_sign_key.data,
554 ntlm_seqnum = gensec_ntlmssp_state->crypt.ntlm.seq_num;
555 ntlm_state = *gensec_ntlmssp_state->crypt.ntlm.arcfour_state;
558 status = gensec_ntlmssp_check_packet(gensec_security, sig_mem_ctx,
559 out->data, out->length,
560 out->data, out->length,
562 if (!NT_STATUS_IS_OK(status)) {
563 NTSTATUS check_status = status;
565 * The Windows LDAP libraries seems to have a bug
566 * and always use sealing even if only signing was
567 * negotiated. So we need to fallback.
570 if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2) {
571 gensec_ntlmssp_state->crypt.ntlm2.recv_seq_num = ntlm2_seqnum_r;
572 *gensec_ntlmssp_state->crypt.ntlm2.recv_seal_arcfour_state = ntlm2_state_r;
573 memcpy(gensec_ntlmssp_state->crypt.ntlm2.recv_sign_key.data,
576 gensec_ntlmssp_state->crypt.ntlm.seq_num = ntlm_seqnum;
577 *gensec_ntlmssp_state->crypt.ntlm.arcfour_state = ntlm_state;
580 status = gensec_ntlmssp_unseal_packet(gensec_security,
587 if (NT_STATUS_IS_OK(status)) {
588 gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_SEAL;
590 status = check_status;
594 if (!NT_STATUS_IS_OK(status)) {
595 DEBUG(1, ("NTLMSSP packet check for unwrap failed due to invalid signature\n"));