xref: /illumos-gate/usr/src/lib/smbsrv/libmlsvc/common/netr_auth.c (revision 8c69cc8fbe729fa7b091e901c4b50508ccc6bb33)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved.
24  * Copyright 2015 Nexenta Systems, Inc.  All rights reserved.
25  */
26 
27 /*
28  * NETR challenge/response client functions.
29  *
30  * NT_STATUS_INVALID_PARAMETER
31  * NT_STATUS_NO_TRUST_SAM_ACCOUNT
32  * NT_STATUS_ACCESS_DENIED
33  */
34 
35 #include <stdio.h>
36 #include <stdlib.h>
37 #include <strings.h>
38 #include <unistd.h>
39 #include <ctype.h>
40 #include <security/cryptoki.h>
41 #include <security/pkcs11.h>
42 
43 #include <smbsrv/libsmb.h>
44 #include <smbsrv/libsmbns.h>
45 #include <smbsrv/libmlsvc.h>
46 #include <smbsrv/ndl/netlogon.ndl>
47 #include <smbsrv/smbinfo.h>
48 #include <smbsrv/netrauth.h>
49 
50 #define	NETR_SESSKEY_ZEROBUF_SZ		4
51 /* The DES algorithm uses a 56-bit encryption key. */
52 #define	NETR_DESKEY_LEN			7
53 
54 int netr_setup_authenticator(netr_info_t *, struct netr_authenticator *,
55     struct netr_authenticator *);
56 DWORD netr_validate_chain(netr_info_t *, struct netr_authenticator *);
57 
58 static int netr_server_req_challenge(mlsvc_handle_t *, netr_info_t *);
59 static int netr_server_authenticate2(mlsvc_handle_t *, netr_info_t *);
60 static int netr_gen_password(BYTE *, BYTE *, BYTE *);
61 
62 /*
63  * Shared with netr_logon.c
64  */
65 netr_info_t netr_global_info;
66 
67 /*
68  * netlogon_auth
69  *
70  * This is the core of the NETLOGON authentication protocol.
71  * Do the challenge response authentication.
72  *
73  * Prior to calling this function, an anonymous session to the NETLOGON
74  * pipe on a domain controller(server) should have already been opened.
75  *
76  * Upon a successful NETLOGON credential chain establishment, the
77  * netlogon sequence number will be set to match the kpasswd sequence
78  * number.
79  *
80  */
81 DWORD
82 netlogon_auth(char *server, mlsvc_handle_t *netr_handle, DWORD flags)
83 {
84 	netr_info_t *netr_info;
85 	int rc;
86 	DWORD leout_rc[2];
87 
88 	netr_info = &netr_global_info;
89 	bzero(netr_info, sizeof (netr_info_t));
90 
91 	netr_info->flags |= flags;
92 
93 	rc = smb_getnetbiosname(netr_info->hostname, NETBIOS_NAME_SZ);
94 	if (rc != 0)
95 		return (NT_STATUS_UNSUCCESSFUL);
96 
97 	/* server is our DC.  Note: normally an FQDN. */
98 	(void) snprintf(netr_info->server, sizeof (netr_info->server),
99 	    "\\\\%s", server);
100 
101 	LE_OUT32(&leout_rc[0], random());
102 	LE_OUT32(&leout_rc[1], random());
103 	(void) memcpy(&netr_info->client_challenge, leout_rc,
104 	    sizeof (struct netr_credential));
105 
106 	if ((rc = netr_server_req_challenge(netr_handle, netr_info)) == 0) {
107 		rc = netr_server_authenticate2(netr_handle, netr_info);
108 		if (rc == 0) {
109 			/*
110 			 * TODO: (later)  When joining a domain using a
111 			 * pre-created machine account, should do:
112 			 * netr_server_password_set(&netr_handle, netr_info);
113 			 * Nexenta issue 11960
114 			 */
115 			smb_update_netlogon_seqnum();
116 			netr_info->flags |= NETR_FLG_VALID;
117 
118 		}
119 	}
120 
121 	return ((rc) ? NT_STATUS_UNSUCCESSFUL : NT_STATUS_SUCCESS);
122 }
123 
124 /*
125  * netr_open
126  *
127  * Open an anonymous session to the NETLOGON pipe on a domain controller
128  * and bind to the NETR RPC interface.
129  *
130  * We store the remote server information, which is used to drive Windows
131  * version specific behavior.
132  *
133  * Returns 0 or NT status
134  */
135 DWORD
136 netr_open(char *server, char *domain, mlsvc_handle_t *netr_handle)
137 {
138 	char user[SMB_USERNAME_MAXLEN];
139 	DWORD status;
140 
141 	smb_ipc_get_user(user, SMB_USERNAME_MAXLEN);
142 
143 	status = ndr_rpc_bind(netr_handle, server, domain, user, "NETR");
144 
145 	return (status);
146 }
147 
148 /*
149  * netr_close
150  *
151  * Close a NETLOGON pipe and free the RPC context.
152  */
153 int
154 netr_close(mlsvc_handle_t *netr_handle)
155 {
156 	ndr_rpc_unbind(netr_handle);
157 	return (0);
158 }
159 
160 /*
161  * netr_server_req_challenge
162  */
163 static int
164 netr_server_req_challenge(mlsvc_handle_t *netr_handle, netr_info_t *netr_info)
165 {
166 	struct netr_ServerReqChallenge arg;
167 	int opnum;
168 
169 	bzero(&arg, sizeof (struct netr_ServerReqChallenge));
170 	opnum = NETR_OPNUM_ServerReqChallenge;
171 
172 	arg.servername = (unsigned char *)netr_info->server;
173 	arg.hostname = (unsigned char *)netr_info->hostname;
174 
175 	(void) memcpy(&arg.client_challenge, &netr_info->client_challenge,
176 	    sizeof (struct netr_credential));
177 
178 	if (ndr_rpc_call(netr_handle, opnum, &arg) != 0)
179 		return (-1);
180 
181 	if (arg.status != 0) {
182 		ndr_rpc_status(netr_handle, opnum, arg.status);
183 		ndr_rpc_release(netr_handle);
184 		return (-1);
185 	}
186 
187 	(void) memcpy(&netr_info->server_challenge, &arg.server_challenge,
188 	    sizeof (struct netr_credential));
189 
190 	ndr_rpc_release(netr_handle);
191 	return (0);
192 }
193 
194 /*
195  * netr_server_authenticate2
196  */
197 static int
198 netr_server_authenticate2(mlsvc_handle_t *netr_handle, netr_info_t *netr_info)
199 {
200 	struct netr_ServerAuthenticate2 arg;
201 	/* sizeof netr_info->hostname, + 1 for the '$' */
202 	char account_name[(NETBIOS_NAME_SZ * 2) + 1];
203 	int opnum;
204 	int rc;
205 
206 	bzero(&arg, sizeof (struct netr_ServerAuthenticate2));
207 	opnum = NETR_OPNUM_ServerAuthenticate2;
208 
209 	(void) snprintf(account_name, sizeof (account_name), "%s$",
210 	    netr_info->hostname);
211 
212 	smb_tracef("server=[%s] account_name=[%s] hostname=[%s]\n",
213 	    netr_info->server, account_name, netr_info->hostname);
214 
215 	arg.servername = (unsigned char *)netr_info->server;
216 	arg.account_name = (unsigned char *)account_name;
217 	arg.account_type = NETR_WKSTA_TRUST_ACCOUNT_TYPE;
218 	arg.hostname = (unsigned char *)netr_info->hostname;
219 	arg.negotiate_flags = NETR_NEGOTIATE_BASE_FLAGS;
220 
221 	if (ndr_rpc_server_os(netr_handle) == NATIVE_OS_WIN2000) {
222 		arg.negotiate_flags |= NETR_NEGOTIATE_STRONGKEY_FLAG;
223 		if (netr_gen_skey128(netr_info) != SMBAUTH_SUCCESS)
224 			return (-1);
225 	} else {
226 		if (netr_gen_skey64(netr_info) != SMBAUTH_SUCCESS)
227 			return (-1);
228 	}
229 
230 	if (netr_gen_credentials(netr_info->session_key.key,
231 	    &netr_info->client_challenge, 0,
232 	    &netr_info->client_credential) != SMBAUTH_SUCCESS) {
233 		return (-1);
234 	}
235 
236 	if (netr_gen_credentials(netr_info->session_key.key,
237 	    &netr_info->server_challenge, 0,
238 	    &netr_info->server_credential) != SMBAUTH_SUCCESS) {
239 		return (-1);
240 	}
241 
242 	(void) memcpy(&arg.client_credential, &netr_info->client_credential,
243 	    sizeof (struct netr_credential));
244 
245 	if (ndr_rpc_call(netr_handle, opnum, &arg) != 0)
246 		return (-1);
247 
248 	if (arg.status != 0) {
249 		ndr_rpc_status(netr_handle, opnum, arg.status);
250 		ndr_rpc_release(netr_handle);
251 		return (-1);
252 	}
253 
254 	rc = memcmp(&netr_info->server_credential, &arg.server_credential,
255 	    sizeof (struct netr_credential));
256 
257 	ndr_rpc_release(netr_handle);
258 	return (rc);
259 }
260 
261 /*
262  * netr_gen_skey128
263  *
264  * Generate a 128-bit session key from the client and server challenges.
265  * See "Session-Key Computation" section of MS-NRPC document.
266  */
267 int
268 netr_gen_skey128(netr_info_t *netr_info)
269 {
270 	unsigned char ntlmhash[SMBAUTH_HASH_SZ];
271 	int rc = SMBAUTH_FAILURE;
272 	CK_RV rv;
273 	CK_MECHANISM mechanism;
274 	CK_SESSION_HANDLE hSession;
275 	CK_ULONG diglen = MD_DIGEST_LEN;
276 	unsigned char md5digest[MD_DIGEST_LEN];
277 	unsigned char zerobuf[NETR_SESSKEY_ZEROBUF_SZ];
278 
279 	bzero(ntlmhash, SMBAUTH_HASH_SZ);
280 	/*
281 	 * We should check (netr_info->flags & NETR_FLG_INIT) and use
282 	 * the appropriate password but it isn't working yet.  So we
283 	 * always use the default one for now.
284 	 */
285 	bzero(netr_info->password, sizeof (netr_info->password));
286 	rc = smb_config_getstr(SMB_CI_MACHINE_PASSWD,
287 	    (char *)netr_info->password, sizeof (netr_info->password));
288 
289 	if ((rc != SMBD_SMF_OK) || *netr_info->password == '\0') {
290 		return (SMBAUTH_FAILURE);
291 	}
292 
293 	rc = smb_auth_ntlm_hash((char *)netr_info->password, ntlmhash);
294 	if (rc != SMBAUTH_SUCCESS)
295 		return (SMBAUTH_FAILURE);
296 
297 	bzero(zerobuf, NETR_SESSKEY_ZEROBUF_SZ);
298 
299 	mechanism.mechanism = CKM_MD5;
300 	mechanism.pParameter = 0;
301 	mechanism.ulParameterLen = 0;
302 
303 	rv = SUNW_C_GetMechSession(mechanism.mechanism, &hSession);
304 	if (rv != CKR_OK)
305 		return (SMBAUTH_FAILURE);
306 
307 	rv = C_DigestInit(hSession, &mechanism);
308 	if (rv != CKR_OK)
309 		goto cleanup;
310 
311 	rv = C_DigestUpdate(hSession, (CK_BYTE_PTR)zerobuf,
312 	    NETR_SESSKEY_ZEROBUF_SZ);
313 	if (rv != CKR_OK)
314 		goto cleanup;
315 
316 	rv = C_DigestUpdate(hSession,
317 	    (CK_BYTE_PTR)netr_info->client_challenge.data, NETR_CRED_DATA_SZ);
318 	if (rv != CKR_OK)
319 		goto cleanup;
320 
321 	rv = C_DigestUpdate(hSession,
322 	    (CK_BYTE_PTR)netr_info->server_challenge.data, NETR_CRED_DATA_SZ);
323 	if (rv != CKR_OK)
324 		goto cleanup;
325 
326 	rv = C_DigestFinal(hSession, (CK_BYTE_PTR)md5digest, &diglen);
327 	if (rv != CKR_OK)
328 		goto cleanup;
329 
330 	rc = smb_auth_hmac_md5(md5digest, diglen, ntlmhash, SMBAUTH_HASH_SZ,
331 	    netr_info->session_key.key);
332 
333 	netr_info->session_key.len = NETR_SESSKEY128_SZ;
334 cleanup:
335 	(void) C_CloseSession(hSession);
336 	return (rc);
337 
338 }
339 /*
340  * netr_gen_skey64
341  *
342  * Generate a 64-bit session key from the client and server challenges.
343  * See "Session-Key Computation" section of MS-NRPC document.
344  *
345  * The algorithm is a two stage hash. For the first hash, the input is
346  * the combination of the client and server challenges, the key is
347  * the first 7 bytes of the password. The initial password is formed
348  * using the NT password hash on the local hostname in lower case.
349  * The result is stored in a temporary buffer.
350  *
351  *		input:	challenge
352  *		key:	passwd lower 7 bytes
353  *		output:	intermediate result
354  *
355  * For the second hash, the input is the result of the first hash and
356  * the key is the last 7 bytes of the password.
357  *
358  *		input:	result of first hash
359  *		key:	passwd upper 7 bytes
360  *		output:	session_key
361  *
362  * The final output should be the session key.
363  *
364  *		FYI: smb_auth_DES(output, key, input)
365  *
366  * If any difficulties occur using the cryptographic framework, the
367  * function returns SMBAUTH_FAILURE.  Otherwise SMBAUTH_SUCCESS is
368  * returned.
369  */
370 int
371 netr_gen_skey64(netr_info_t *netr_info)
372 {
373 	unsigned char md4hash[32];
374 	unsigned char buffer[8];
375 	DWORD data[2];
376 	DWORD *client_challenge;
377 	DWORD *server_challenge;
378 	int rc;
379 	DWORD le_data[2];
380 
381 	client_challenge = (DWORD *)(uintptr_t)&netr_info->client_challenge;
382 	server_challenge = (DWORD *)(uintptr_t)&netr_info->server_challenge;
383 	bzero(md4hash, 32);
384 
385 	/*
386 	 * We should check (netr_info->flags & NETR_FLG_INIT) and use
387 	 * the appropriate password but it isn't working yet.  So we
388 	 * always use the default one for now.
389 	 */
390 	bzero(netr_info->password, sizeof (netr_info->password));
391 	rc = smb_config_getstr(SMB_CI_MACHINE_PASSWD,
392 	    (char *)netr_info->password, sizeof (netr_info->password));
393 
394 	if ((rc != SMBD_SMF_OK) || *netr_info->password == '\0') {
395 		return (SMBAUTH_FAILURE);
396 	}
397 
398 	rc = smb_auth_ntlm_hash((char *)netr_info->password, md4hash);
399 
400 	if (rc != SMBAUTH_SUCCESS)
401 		return (SMBAUTH_FAILURE);
402 
403 	data[0] = LE_IN32(&client_challenge[0]) + LE_IN32(&server_challenge[0]);
404 	data[1] = LE_IN32(&client_challenge[1]) + LE_IN32(&server_challenge[1]);
405 	LE_OUT32(&le_data[0], data[0]);
406 	LE_OUT32(&le_data[1], data[1]);
407 	rc = smb_auth_DES(buffer, 8, md4hash, NETR_DESKEY_LEN,
408 	    (unsigned char *)le_data, 8);
409 
410 	if (rc != SMBAUTH_SUCCESS)
411 		return (rc);
412 
413 	netr_info->session_key.len = NETR_SESSKEY64_SZ;
414 	rc = smb_auth_DES(netr_info->session_key.key,
415 	    netr_info->session_key.len, &md4hash[9], NETR_DESKEY_LEN, buffer,
416 	    8);
417 
418 	return (rc);
419 }
420 
421 /*
422  * netr_gen_credentials
423  *
424  * Generate a set of credentials from a challenge and a session key.
425  * The algorithm is a two stage hash. For the first hash, the
426  * timestamp is added to the challenge and the result is stored in a
427  * temporary buffer:
428  *
429  *		input:	challenge (including timestamp)
430  *		key:	session_key
431  *		output:	intermediate result
432  *
433  * For the second hash, the input is the result of the first hash and
434  * a strange partial key is used:
435  *
436  *		input:	result of first hash
437  *		key:	funny partial key
438  *		output:	credentiails
439  *
440  * The final output should be an encrypted set of credentials.
441  *
442  *		FYI: smb_auth_DES(output, key, input)
443  *
444  * If any difficulties occur using the cryptographic framework, the
445  * function returns SMBAUTH_FAILURE.  Otherwise SMBAUTH_SUCCESS is
446  * returned.
447  */
448 int
449 netr_gen_credentials(BYTE *session_key, netr_cred_t *challenge,
450     DWORD timestamp, netr_cred_t *out_cred)
451 {
452 	unsigned char buffer[8];
453 	DWORD data[2];
454 	DWORD le_data[2];
455 	DWORD *p;
456 	int rc;
457 
458 	p = (DWORD *)(uintptr_t)challenge;
459 	data[0] = LE_IN32(&p[0]) + timestamp;
460 	data[1] = LE_IN32(&p[1]);
461 
462 	LE_OUT32(&le_data[0], data[0]);
463 	LE_OUT32(&le_data[1], data[1]);
464 
465 	if (smb_auth_DES(buffer, 8, session_key, NETR_DESKEY_LEN,
466 	    (unsigned char *)le_data, 8) != SMBAUTH_SUCCESS)
467 		return (SMBAUTH_FAILURE);
468 
469 	rc = smb_auth_DES(out_cred->data, 8, &session_key[NETR_DESKEY_LEN],
470 	    NETR_DESKEY_LEN, buffer, 8);
471 
472 	return (rc);
473 }
474 
475 /*
476  * netr_server_password_set
477  *
478  * Attempt to change the trust account password for this system.
479  *
480  * Note that this call may legitimately fail if the registry on the
481  * domain controller has been setup to deny attempts to change the
482  * trust account password. In this case we should just continue to
483  * use the original password.
484  *
485  * Possible status values:
486  *	NT_STATUS_ACCESS_DENIED
487  */
488 int
489 netr_server_password_set(mlsvc_handle_t *netr_handle, netr_info_t *netr_info)
490 {
491 	struct netr_PasswordSet  arg;
492 	int opnum;
493 	BYTE new_password[NETR_OWF_PASSWORD_SZ];
494 	char account_name[NETBIOS_NAME_SZ * 2];
495 
496 	bzero(&arg, sizeof (struct netr_PasswordSet));
497 	opnum = NETR_OPNUM_ServerPasswordSet;
498 
499 	(void) snprintf(account_name, sizeof (account_name), "%s$",
500 	    netr_info->hostname);
501 
502 	arg.servername = (unsigned char *)netr_info->server;
503 	arg.account_name = (unsigned char *)account_name;
504 	arg.sec_chan_type = NETR_WKSTA_TRUST_ACCOUNT_TYPE;
505 	arg.hostname = (unsigned char *)netr_info->hostname;
506 
507 	/*
508 	 * Set up the client side authenticator.
509 	 */
510 	if (netr_setup_authenticator(netr_info, &arg.auth, 0) !=
511 	    SMBAUTH_SUCCESS) {
512 		return (-1);
513 	}
514 
515 	/*
516 	 * Generate a new password from the old password.
517 	 */
518 	if (netr_gen_password(netr_info->session_key.key,
519 	    netr_info->password, new_password) == SMBAUTH_FAILURE) {
520 		return (-1);
521 	}
522 
523 	(void) memcpy(&arg.owf_password, &new_password,
524 	    NETR_OWF_PASSWORD_SZ);
525 
526 	if (ndr_rpc_call(netr_handle, opnum, &arg) != 0)
527 		return (-1);
528 
529 	if (arg.status != 0) {
530 		ndr_rpc_status(netr_handle, opnum, arg.status);
531 		ndr_rpc_release(netr_handle);
532 		return (-1);
533 	}
534 
535 	/*
536 	 * Check the returned credentials.  The server returns the new
537 	 * client credential rather than the new server credentiali,
538 	 * as documented elsewhere.
539 	 *
540 	 * Generate the new seed for the credential chain.  Increment
541 	 * the timestamp and add it to the client challenge.  Then we
542 	 * need to copy the challenge to the credential field in
543 	 * preparation for the next cycle.
544 	 */
545 	if (netr_validate_chain(netr_info, &arg.auth) == 0) {
546 		/*
547 		 * Save the new password.
548 		 */
549 		(void) memcpy(netr_info->password, new_password,
550 		    NETR_OWF_PASSWORD_SZ);
551 	}
552 
553 	ndr_rpc_release(netr_handle);
554 	return (0);
555 }
556 
557 /*
558  * netr_gen_password
559  *
560  * Generate a new pasword from the old password  and the session key.
561  * The algorithm is a two stage hash. The session key is used in the
562  * first hash but only part of the session key is used in the second
563  * hash.
564  *
565  * If any difficulties occur using the cryptographic framework, the
566  * function returns SMBAUTH_FAILURE.  Otherwise SMBAUTH_SUCCESS is
567  * returned.
568  */
569 static int
570 netr_gen_password(BYTE *session_key, BYTE *old_password, BYTE *new_password)
571 {
572 	int rv;
573 
574 	rv = smb_auth_DES(new_password, 8, session_key, NETR_DESKEY_LEN,
575 	    old_password, 8);
576 	if (rv != SMBAUTH_SUCCESS)
577 		return (rv);
578 
579 	rv = smb_auth_DES(&new_password[8], 8, &session_key[NETR_DESKEY_LEN],
580 	    NETR_DESKEY_LEN, &old_password[8], 8);
581 	return (rv);
582 }
583 
584 /*
585  * Todo: need netr_server_password_set2()
586  * used by "unsecure join". (NX 11960)
587  */
588