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/auth.h"
24 #include "auth/ntlmssp/ntlmssp.h"
25 #include "auth/ntlmssp/msrpc_parse.h"
26 #include "lib/crypto/crypto.h"
27 #include "auth/credentials/credentials.h"
28 #include "auth/gensec/gensec.h"
30 #define CLI_SIGN "session key to client-to-server signing key magic constant"
31 #define CLI_SEAL "session key to client-to-server sealing key magic constant"
32 #define SRV_SIGN "session key to server-to-client signing key magic constant"
33 #define SRV_SEAL "session key to server-to-client sealing key magic constant"
36 * Some notes on the NTLM2 code:
38 * NTLM2 is a AEAD system. This means that the data encrypted is not
39 * all the data that is signed. In DCE-RPC case, the headers of the
40 * DCE-RPC packets are also signed. This prevents some of the
41 * fun-and-games one might have by changing them.
45 static void calc_ntlmv2_key(TALLOC_CTX *mem_ctx,
47 DATA_BLOB session_key,
50 struct MD5Context ctx3;
51 *subkey = data_blob_talloc(mem_ctx, NULL, 16);
53 MD5Update(&ctx3, session_key.data, session_key.length);
54 MD5Update(&ctx3, (const uint8_t *)constant, strlen(constant)+1);
55 MD5Final(subkey->data, &ctx3);
58 enum ntlmssp_direction {
63 static NTSTATUS ntlmssp_make_packet_signature(struct gensec_ntlmssp_state *gensec_ntlmssp_state,
64 TALLOC_CTX *sig_mem_ctx,
65 const uint8_t *data, size_t length,
66 const uint8_t *whole_pdu, size_t pdu_length,
67 enum ntlmssp_direction direction,
68 DATA_BLOB *sig, bool encrypt_sig)
70 if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2) {
76 *sig = data_blob_talloc(sig_mem_ctx, NULL, NTLMSSP_SIG_SIZE);
78 return NT_STATUS_NO_MEMORY;
83 SIVAL(seq_num, 0, gensec_ntlmssp_state->crypt.ntlm2.send_seq_num);
84 gensec_ntlmssp_state->crypt.ntlm2.send_seq_num++;
85 hmac_md5_init_limK_to_64(gensec_ntlmssp_state->crypt.ntlm2.send_sign_key.data,
86 gensec_ntlmssp_state->crypt.ntlm2.send_sign_key.length, &ctx);
89 SIVAL(seq_num, 0, gensec_ntlmssp_state->crypt.ntlm2.recv_seq_num);
90 gensec_ntlmssp_state->crypt.ntlm2.recv_seq_num++;
91 hmac_md5_init_limK_to_64(gensec_ntlmssp_state->crypt.ntlm2.recv_sign_key.data,
92 gensec_ntlmssp_state->crypt.ntlm2.recv_sign_key.length, &ctx);
95 hmac_md5_update(seq_num, sizeof(seq_num), &ctx);
96 hmac_md5_update(whole_pdu, pdu_length, &ctx);
97 hmac_md5_final(digest, &ctx);
99 if (encrypt_sig && gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_KEY_EXCH) {
102 arcfour_crypt_sbox(gensec_ntlmssp_state->crypt.ntlm2.send_seal_arcfour_state, digest, 8);
104 case NTLMSSP_RECEIVE:
105 arcfour_crypt_sbox(gensec_ntlmssp_state->crypt.ntlm2.recv_seal_arcfour_state, digest, 8);
110 SIVAL(sig->data, 0, NTLMSSP_SIGN_VERSION);
111 memcpy(sig->data + 4, digest, 8);
112 memcpy(sig->data + 12, seq_num, 4);
114 DEBUG(10, ("NTLM2: created signature over %llu bytes of input:\n", (unsigned long long)pdu_length));
115 dump_data(11, sig->data, sig->length);
119 crc = crc32_calc_buffer(data, length);
120 if (!msrpc_gen(sig_mem_ctx, sig, "dddd", NTLMSSP_SIGN_VERSION, 0, crc, gensec_ntlmssp_state->crypt.ntlm.seq_num)) {
121 return NT_STATUS_NO_MEMORY;
123 gensec_ntlmssp_state->crypt.ntlm.seq_num++;
125 arcfour_crypt_sbox(gensec_ntlmssp_state->crypt.ntlm.arcfour_state, sig->data+4, sig->length-4);
127 DEBUG(10, ("NTLM1: created signature over %llu bytes of input:\n", (unsigned long long)length));
128 dump_data(11, sig->data, sig->length);
133 /* TODO: make this non-public */
134 _PUBLIC_ NTSTATUS 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,
140 struct gensec_ntlmssp_state *gensec_ntlmssp_state = (struct gensec_ntlmssp_state *)gensec_security->private_data;
142 return ntlmssp_make_packet_signature(gensec_ntlmssp_state, sig_mem_ctx,
144 whole_pdu, pdu_length,
145 NTLMSSP_SEND, sig, true);
149 * Check the signature of an incoming packet
153 NTSTATUS 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)
159 struct gensec_ntlmssp_state *gensec_ntlmssp_state = (struct gensec_ntlmssp_state *)gensec_security->private_data;
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;
169 nt_status = ntlmssp_make_packet_signature(gensec_ntlmssp_state, sig_mem_ctx,
171 whole_pdu, pdu_length,
172 NTLMSSP_RECEIVE, &local_sig, true);
174 if (!NT_STATUS_IS_OK(nt_status)) {
175 DEBUG(0, ("NTLMSSP packet check failed with %s\n", nt_errstr(nt_status)));
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);
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);
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;
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);
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);
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;
206 dump_data_pw("checked ntlmssp signature\n", sig->data, sig->length);
213 * Seal data with the NTLMSSP algorithm
217 NTSTATUS 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,
223 struct gensec_ntlmssp_state *gensec_ntlmssp_state = (struct gensec_ntlmssp_state *)gensec_security->private_data;
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;
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,
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);
246 crc = crc32_calc_buffer(data, length);
247 if (!msrpc_gen(sig_mem_ctx, 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 _PUBLIC_ 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,