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 check 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) {
182 DEBUG(5, ("BAD SIG NTLM2: wanted signature over %llu bytes of input:\n", (unsigned long long)pdu_length));
183 dump_data(5, local_sig.data, local_sig.length);
185 DEBUG(5, ("BAD SIG: got signature over %llu bytes of input:\n", (unsigned long long)pdu_length));
186 dump_data(5, sig->data, sig->length);
188 DEBUG(1, ("NTLMSSP NTLM2 packet check failed due to invalid signature on %llu bytes of input!\n", (unsigned long long)pdu_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(5, ("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(5, ("BAD SIG: got signature of %llu bytes of input:\n", (unsigned long long)length));
199 dump_data(5, sig->data, sig->length);
201 DEBUG(1, ("NTLMSSP NTLM1 packet check failed due to invalid signature on %llu bytes of input:\n", (unsigned long long)length));
202 return NT_STATUS_ACCESS_DENIED;
205 dump_data_pw("checked ntlmssp signature\n", sig->data, sig->length);
212 * Seal data with the NTLMSSP algorithm
216 NTSTATUS gensec_ntlmssp_seal_packet(struct gensec_security *gensec_security,
217 TALLOC_CTX *sig_mem_ctx,
218 uint8_t *data, size_t length,
219 const uint8_t *whole_pdu, size_t pdu_length,
222 struct gensec_ntlmssp_state *gensec_ntlmssp_state = (struct gensec_ntlmssp_state *)gensec_security->private_data;
224 if (!gensec_ntlmssp_state->session_key.length) {
225 DEBUG(3, ("NO session key, cannot seal packet\n"));
226 return NT_STATUS_NO_USER_SESSION_KEY;
229 DEBUG(10,("ntlmssp_seal_data: seal\n"));
230 dump_data_pw("ntlmssp clear data\n", data, length);
231 if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2) {
232 /* The order of these two operations matters - we must first seal the packet,
233 then seal the sequence number - this is becouse the send_seal_hash is not
234 constant, but is is rather updated with each iteration */
235 nt_status = ntlmssp_make_packet_signature(gensec_ntlmssp_state, sig_mem_ctx,
237 whole_pdu, pdu_length,
238 NTLMSSP_SEND, sig, false);
239 arcfour_crypt_sbox(gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state, data, length);
240 if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_KEY_EXCH) {
241 arcfour_crypt_sbox(gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state, sig->data+4, 8);
245 crc = crc32_calc_buffer(data, length);
246 if (!msrpc_gen(sig_mem_ctx,
247 sig, "dddd", NTLMSSP_SIGN_VERSION, 0, crc, gensec_ntlmssp_state->crypt.ntlm.seq_num)) {
248 return NT_STATUS_NO_MEMORY;
251 /* The order of these two operations matters - we must
252 first seal the packet, then seal the sequence
253 number - this is becouse the ntlmssp_hash is not
254 constant, but is is rather updated with each
257 arcfour_crypt_sbox(gensec_ntlmssp_state->crypt.ntlm.arcfour_state, data, length);
258 arcfour_crypt_sbox(gensec_ntlmssp_state->crypt.ntlm.arcfour_state, sig->data+4, sig->length-4);
259 /* increment counter on send */
260 gensec_ntlmssp_state->crypt.ntlm.seq_num++;
261 nt_status = NT_STATUS_OK;
263 dump_data_pw("ntlmssp signature\n", sig->data, sig->length);
264 dump_data_pw("ntlmssp sealed data\n", data, length);
271 * Unseal data with the NTLMSSP algorithm
276 wrappers for the ntlmssp_*() functions
278 NTSTATUS gensec_ntlmssp_unseal_packet(struct gensec_security *gensec_security,
279 TALLOC_CTX *sig_mem_ctx,
280 uint8_t *data, size_t length,
281 const uint8_t *whole_pdu, size_t pdu_length,
282 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 return gensec_ntlmssp_check_packet(gensec_security, sig_mem_ctx, data, length, whole_pdu, pdu_length, sig);
301 Initialise the state for NTLMSSP signing.
303 /* TODO: make this non-public */
304 NTSTATUS ntlmssp_sign_init(struct gensec_ntlmssp_state *gensec_ntlmssp_state)
306 TALLOC_CTX *mem_ctx = talloc_new(gensec_ntlmssp_state);
309 return NT_STATUS_NO_MEMORY;
312 DEBUG(3, ("NTLMSSP Sign/Seal - Initialising with flags:\n"));
313 debug_ntlmssp_flags(gensec_ntlmssp_state->neg_flags);
315 if (gensec_ntlmssp_state->session_key.length < 8) {
316 talloc_free(mem_ctx);
317 DEBUG(3, ("NO session key, cannot intialise signing\n"));
318 return NT_STATUS_NO_USER_SESSION_KEY;
321 if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2)
323 DATA_BLOB weak_session_key = gensec_ntlmssp_state->session_key;
324 const char *send_sign_const;
325 const char *send_seal_const;
326 const char *recv_sign_const;
327 const char *recv_seal_const;
329 DATA_BLOB send_seal_key;
330 DATA_BLOB recv_seal_key;
332 switch (gensec_ntlmssp_state->role) {
334 send_sign_const = CLI_SIGN;
335 send_seal_const = CLI_SEAL;
336 recv_sign_const = SRV_SIGN;
337 recv_seal_const = SRV_SEAL;
340 send_sign_const = SRV_SIGN;
341 send_seal_const = SRV_SEAL;
342 recv_sign_const = CLI_SIGN;
343 recv_seal_const = CLI_SEAL;
346 talloc_free(mem_ctx);
347 return NT_STATUS_INTERNAL_ERROR;
350 gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state = talloc(gensec_ntlmssp_state, struct arcfour_state);
351 NT_STATUS_HAVE_NO_MEMORY(gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state);
352 gensec_ntlmssp_state->crypt.ntlm2.recv_seal_arcfour_state = talloc(gensec_ntlmssp_state, struct arcfour_state);
353 NT_STATUS_HAVE_NO_MEMORY(gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state);
356 Weaken NTLMSSP keys to cope with down-level
357 clients, servers and export restrictions.
359 We probably should have some parameters to control
360 this, once we get NTLM2 working.
363 /* Key weakening was not performed on the master key
364 * for NTLM2 (in ntlmssp_weaken_keys()), but must be
365 * done on the encryption subkeys only. That is why
366 * we don't have this code for the ntlmv1 case.
369 if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_128) {
371 } else if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_56) {
372 weak_session_key.length = 7;
373 } else { /* forty bits */
374 weak_session_key.length = 5;
376 dump_data_pw("NTLMSSP weakend master key:\n",
377 weak_session_key.data,
378 weak_session_key.length);
381 calc_ntlmv2_key(gensec_ntlmssp_state,
382 &gensec_ntlmssp_state->crypt.ntlm2.send_sign_key,
383 gensec_ntlmssp_state->session_key, send_sign_const);
384 dump_data_pw("NTLMSSP send sign key:\n",
385 gensec_ntlmssp_state->crypt.ntlm2.send_sign_key.data,
386 gensec_ntlmssp_state->crypt.ntlm2.send_sign_key.length);
388 /* SEND: seal ARCFOUR pad */
389 calc_ntlmv2_key(mem_ctx,
391 weak_session_key, send_seal_const);
392 dump_data_pw("NTLMSSP send seal key:\n",
394 send_seal_key.length);
395 arcfour_init(gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state,
397 dump_data_pw("NTLMSSP send sesl hash:\n",
398 gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state->sbox,
399 sizeof(gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state->sbox));
402 calc_ntlmv2_key(gensec_ntlmssp_state,
403 &gensec_ntlmssp_state->crypt.ntlm2.recv_sign_key,
404 gensec_ntlmssp_state->session_key, recv_sign_const);
405 dump_data_pw("NTLMSSP recv sign key:\n",
406 gensec_ntlmssp_state->crypt.ntlm2.recv_sign_key.data,
407 gensec_ntlmssp_state->crypt.ntlm2.recv_sign_key.length);
409 /* RECV: seal ARCFOUR pad */
410 calc_ntlmv2_key(mem_ctx,
412 weak_session_key, recv_seal_const);
413 dump_data_pw("NTLMSSP recv seal key:\n",
415 recv_seal_key.length);
416 arcfour_init(gensec_ntlmssp_state->crypt.ntlm2.recv_seal_arcfour_state,
418 dump_data_pw("NTLMSSP receive seal hash:\n",
419 gensec_ntlmssp_state->crypt.ntlm2.recv_seal_arcfour_state->sbox,
420 sizeof(gensec_ntlmssp_state->crypt.ntlm2.recv_seal_arcfour_state->sbox));
422 gensec_ntlmssp_state->crypt.ntlm2.send_seq_num = 0;
423 gensec_ntlmssp_state->crypt.ntlm2.recv_seq_num = 0;
426 DATA_BLOB weak_session_key = ntlmssp_weakend_key(gensec_ntlmssp_state, mem_ctx);
427 DEBUG(5, ("NTLMSSP Sign/Seal - using NTLM1\n"));
429 gensec_ntlmssp_state->crypt.ntlm.arcfour_state = talloc(gensec_ntlmssp_state, struct arcfour_state);
430 NT_STATUS_HAVE_NO_MEMORY(gensec_ntlmssp_state->crypt.ntlm.arcfour_state);
432 arcfour_init(gensec_ntlmssp_state->crypt.ntlm.arcfour_state,
434 dump_data_pw("NTLMSSP hash:\n", gensec_ntlmssp_state->crypt.ntlm.arcfour_state->sbox,
435 sizeof(gensec_ntlmssp_state->crypt.ntlm.arcfour_state->sbox));
437 gensec_ntlmssp_state->crypt.ntlm.seq_num = 0;
440 talloc_free(mem_ctx);
444 size_t gensec_ntlmssp_sig_size(struct gensec_security *gensec_security, size_t data_size)
446 return NTLMSSP_SIG_SIZE;
449 NTSTATUS gensec_ntlmssp_wrap(struct gensec_security *gensec_security,
450 TALLOC_CTX *sig_mem_ctx,
457 if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
459 *out = data_blob_talloc(sig_mem_ctx, NULL, in->length + NTLMSSP_SIG_SIZE);
461 return NT_STATUS_NO_MEMORY;
463 memcpy(out->data + NTLMSSP_SIG_SIZE, in->data, in->length);
465 nt_status = gensec_ntlmssp_seal_packet(gensec_security, sig_mem_ctx,
466 out->data + NTLMSSP_SIG_SIZE,
467 out->length - NTLMSSP_SIG_SIZE,
468 out->data + NTLMSSP_SIG_SIZE,
469 out->length - NTLMSSP_SIG_SIZE,
472 if (NT_STATUS_IS_OK(nt_status)) {
473 memcpy(out->data, sig.data, NTLMSSP_SIG_SIZE);
477 } else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
479 *out = data_blob_talloc(sig_mem_ctx, NULL, in->length + NTLMSSP_SIG_SIZE);
481 return NT_STATUS_NO_MEMORY;
483 memcpy(out->data + NTLMSSP_SIG_SIZE, in->data, in->length);
485 nt_status = gensec_ntlmssp_sign_packet(gensec_security, sig_mem_ctx,
486 out->data + NTLMSSP_SIG_SIZE,
487 out->length - NTLMSSP_SIG_SIZE,
488 out->data + NTLMSSP_SIG_SIZE,
489 out->length - NTLMSSP_SIG_SIZE,
492 if (NT_STATUS_IS_OK(nt_status)) {
493 memcpy(out->data, sig.data, NTLMSSP_SIG_SIZE);
504 NTSTATUS gensec_ntlmssp_unwrap(struct gensec_security *gensec_security,
505 TALLOC_CTX *sig_mem_ctx,
511 if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
512 if (in->length < NTLMSSP_SIG_SIZE) {
513 return NT_STATUS_INVALID_PARAMETER;
516 sig.length = NTLMSSP_SIG_SIZE;
518 *out = data_blob_talloc(sig_mem_ctx, in->data + NTLMSSP_SIG_SIZE, in->length - NTLMSSP_SIG_SIZE);
520 return gensec_ntlmssp_unseal_packet(gensec_security, sig_mem_ctx,
521 out->data, out->length,
522 out->data, out->length,
525 } else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
526 if (in->length < NTLMSSP_SIG_SIZE) {
527 return NT_STATUS_INVALID_PARAMETER;
530 sig.length = NTLMSSP_SIG_SIZE;
532 *out = data_blob_talloc(sig_mem_ctx, in->data + NTLMSSP_SIG_SIZE, in->length - NTLMSSP_SIG_SIZE);
534 return gensec_ntlmssp_check_packet(gensec_security, sig_mem_ctx,
535 out->data, out->length,
536 out->data, out->length,