xref: /titanic_50/usr/src/lib/smbsrv/libmlsvc/common/netr_auth.c (revision 408aef6a222bf32dc7e66db1ff562316a425ee72)
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  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 /*
27  * NETR challenge/response client functions.
28  *
29  * NT_STATUS_INVALID_PARAMETER
30  * NT_STATUS_NO_TRUST_SAM_ACCOUNT
31  * NT_STATUS_ACCESS_DENIED
32  */
33 
34 #include <stdio.h>
35 #include <stdlib.h>
36 #include <strings.h>
37 #include <unistd.h>
38 #include <ctype.h>
39 #include <security/cryptoki.h>
40 #include <security/pkcs11.h>
41 
42 #include <smbsrv/libsmb.h>
43 #include <smbsrv/libsmbrdr.h>
44 #include <smbsrv/libsmbns.h>
45 #include <smbsrv/libmlsvc.h>
46 #include <smbsrv/ndl/netlogon.ndl>
47 #include <smbsrv/ntstatus.h>
48 #include <smbsrv/smbinfo.h>
49 #include <smbsrv/netrauth.h>
50 
51 #define	NETR_SESSKEY_ZEROBUF_SZ		4
52 /* The DES algorithm uses a 56-bit encryption key. */
53 #define	NETR_DESKEY_LEN			7
54 
55 int netr_setup_authenticator(netr_info_t *, struct netr_authenticator *,
56     struct netr_authenticator *);
57 DWORD netr_validate_chain(netr_info_t *, struct netr_authenticator *);
58 
59 static int netr_server_req_challenge(mlsvc_handle_t *, netr_info_t *);
60 static int netr_server_authenticate2(mlsvc_handle_t *, netr_info_t *);
61 static int netr_gen_password(BYTE *, BYTE *, BYTE *);
62 
63 /*
64  * Shared with netr_logon.c
65  */
66 netr_info_t netr_global_info;
67 
68 /*
69  * netlogon_auth
70  *
71  * This is the core of the NETLOGON authentication protocol.
72  * Do the challenge response authentication.
73  *
74  * Prior to calling this function, an anonymous session to the NETLOGON
75  * pipe on a domain controller(server) should have already been opened.
76  *
77  * Upon a successful NETLOGON credential chain establishment, the
78  * netlogon sequence number will be set to match the kpasswd sequence
79  * number.
80  *
81  */
82 DWORD
83 netlogon_auth(char *server, mlsvc_handle_t *netr_handle, DWORD flags)
84 {
85 	netr_info_t *netr_info;
86 	int rc;
87 	DWORD leout_rc[2];
88 
89 	netr_info = &netr_global_info;
90 	bzero(netr_info, sizeof (netr_info_t));
91 
92 	netr_info->flags |= flags;
93 
94 	rc = smb_getnetbiosname(netr_info->hostname, NETBIOS_NAME_SZ);
95 	if (rc != 0)
96 		return (NT_STATUS_UNSUCCESSFUL);
97 
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 			smb_update_netlogon_seqnum();
110 			netr_info->flags |= NETR_FLG_VALID;
111 
112 		}
113 	}
114 
115 	return ((rc) ? NT_STATUS_UNSUCCESSFUL : NT_STATUS_SUCCESS);
116 }
117 
118 /*
119  * netr_open
120  *
121  * Open an anonymous session to the NETLOGON pipe on a domain
122  * controller and bind to the NETR RPC interface. We store the
123  * remote server's native OS type - we may need it due to
124  * differences between versions of Windows.
125  */
126 int
127 netr_open(char *server, char *domain, mlsvc_handle_t *netr_handle)
128 {
129 	char *user = smbrdr_ipc_get_user();
130 
131 	if (ndr_rpc_bind(netr_handle, server, domain, user, "NETR") < 0)
132 		return (-1);
133 
134 	return (0);
135 }
136 
137 /*
138  * netr_close
139  *
140  * Close a NETLOGON pipe and free the RPC context.
141  */
142 int
143 netr_close(mlsvc_handle_t *netr_handle)
144 {
145 	ndr_rpc_unbind(netr_handle);
146 	return (0);
147 }
148 
149 /*
150  * netr_server_req_challenge
151  */
152 static int
153 netr_server_req_challenge(mlsvc_handle_t *netr_handle, netr_info_t *netr_info)
154 {
155 	struct netr_ServerReqChallenge arg;
156 	int opnum;
157 
158 	bzero(&arg, sizeof (struct netr_ServerReqChallenge));
159 	opnum = NETR_OPNUM_ServerReqChallenge;
160 
161 	arg.servername = (unsigned char *)netr_info->server;
162 	arg.hostname = (unsigned char *)netr_info->hostname;
163 
164 	(void) memcpy(&arg.client_challenge, &netr_info->client_challenge,
165 	    sizeof (struct netr_credential));
166 
167 	if (ndr_rpc_call(netr_handle, opnum, &arg) != 0)
168 		return (-1);
169 
170 	if (arg.status != 0) {
171 		ndr_rpc_status(netr_handle, opnum, arg.status);
172 		ndr_rpc_release(netr_handle);
173 		return (-1);
174 	}
175 
176 	(void) memcpy(&netr_info->server_challenge, &arg.server_challenge,
177 	    sizeof (struct netr_credential));
178 
179 	ndr_rpc_release(netr_handle);
180 	return (0);
181 }
182 
183 /*
184  * netr_server_authenticate2
185  */
186 static int
187 netr_server_authenticate2(mlsvc_handle_t *netr_handle, netr_info_t *netr_info)
188 {
189 	struct netr_ServerAuthenticate2 arg;
190 	int opnum;
191 	int rc;
192 	char account_name[NETBIOS_NAME_SZ * 2];
193 
194 	bzero(&arg, sizeof (struct netr_ServerAuthenticate2));
195 	opnum = NETR_OPNUM_ServerAuthenticate2;
196 
197 	(void) snprintf(account_name, sizeof (account_name), "%s$",
198 	    netr_info->hostname);
199 
200 	smb_tracef("server=[%s] account_name=[%s] hostname=[%s]\n",
201 	    netr_info->server, account_name, netr_info->hostname);
202 
203 	arg.servername = (unsigned char *)netr_info->server;
204 	arg.account_name = (unsigned char *)account_name;
205 	arg.account_type = NETR_WKSTA_TRUST_ACCOUNT_TYPE;
206 	arg.hostname = (unsigned char *)netr_info->hostname;
207 	arg.negotiate_flags = NETR_NEGOTIATE_BASE_FLAGS;
208 
209 	if (ndr_rpc_server_os(netr_handle) != NATIVE_OS_WINNT) {
210 		arg.negotiate_flags |= NETR_NEGOTIATE_STRONGKEY_FLAG;
211 		if (netr_gen_skey128(netr_info) != SMBAUTH_SUCCESS)
212 			return (-1);
213 	} else {
214 		if (netr_gen_skey64(netr_info) != SMBAUTH_SUCCESS)
215 			return (-1);
216 	}
217 
218 	if (netr_gen_credentials(netr_info->session_key.key,
219 	    &netr_info->client_challenge, 0,
220 	    &netr_info->client_credential) != SMBAUTH_SUCCESS) {
221 		return (-1);
222 	}
223 
224 	if (netr_gen_credentials(netr_info->session_key.key,
225 	    &netr_info->server_challenge, 0,
226 	    &netr_info->server_credential) != SMBAUTH_SUCCESS) {
227 		return (-1);
228 	}
229 
230 	(void) memcpy(&arg.client_credential, &netr_info->client_credential,
231 	    sizeof (struct netr_credential));
232 
233 	if (ndr_rpc_call(netr_handle, opnum, &arg) != 0)
234 		return (-1);
235 
236 	if (arg.status != 0) {
237 		ndr_rpc_status(netr_handle, opnum, arg.status);
238 		ndr_rpc_release(netr_handle);
239 		return (-1);
240 	}
241 
242 	rc = memcmp(&netr_info->server_credential, &arg.server_credential,
243 	    sizeof (struct netr_credential));
244 
245 	ndr_rpc_release(netr_handle);
246 	return (rc);
247 }
248 
249 /*
250  * netr_gen_skey128
251  *
252  * Generate a 128-bit session key from the client and server challenges.
253  * See "Session-Key Computation" section of MS-NRPC document.
254  */
255 int
256 netr_gen_skey128(netr_info_t *netr_info)
257 {
258 	unsigned char ntlmhash[SMBAUTH_HASH_SZ];
259 	int rc = SMBAUTH_FAILURE;
260 	CK_RV rv;
261 	CK_MECHANISM mechanism;
262 	CK_SESSION_HANDLE hSession;
263 	CK_ULONG diglen = MD_DIGEST_LEN;
264 	unsigned char md5digest[MD_DIGEST_LEN];
265 	unsigned char zerobuf[NETR_SESSKEY_ZEROBUF_SZ];
266 
267 	bzero(ntlmhash, SMBAUTH_HASH_SZ);
268 	/*
269 	 * We should check (netr_info->flags & NETR_FLG_INIT) and use
270 	 * the appropriate password but it isn't working yet.  So we
271 	 * always use the default one for now.
272 	 */
273 	bzero(netr_info->password, sizeof (netr_info->password));
274 	rc = smb_config_getstr(SMB_CI_MACHINE_PASSWD,
275 	    (char *)netr_info->password, sizeof (netr_info->password));
276 
277 	if ((rc != SMBD_SMF_OK) || *netr_info->password == '\0') {
278 		return (SMBAUTH_FAILURE);
279 	}
280 
281 	rc = smb_auth_ntlm_hash((char *)netr_info->password, ntlmhash);
282 	if (rc != SMBAUTH_SUCCESS)
283 		return (SMBAUTH_FAILURE);
284 
285 	bzero(zerobuf, NETR_SESSKEY_ZEROBUF_SZ);
286 
287 	mechanism.mechanism = CKM_MD5;
288 	mechanism.pParameter = 0;
289 	mechanism.ulParameterLen = 0;
290 
291 	rv = SUNW_C_GetMechSession(mechanism.mechanism, &hSession);
292 	if (rv != CKR_OK)
293 		return (SMBAUTH_FAILURE);
294 
295 	rv = C_DigestInit(hSession, &mechanism);
296 	if (rv != CKR_OK)
297 		goto cleanup;
298 
299 	rv = C_DigestUpdate(hSession, (CK_BYTE_PTR)zerobuf,
300 	    NETR_SESSKEY_ZEROBUF_SZ);
301 	if (rv != CKR_OK)
302 		goto cleanup;
303 
304 	rv = C_DigestUpdate(hSession,
305 	    (CK_BYTE_PTR)netr_info->client_challenge.data, NETR_CRED_DATA_SZ);
306 	if (rv != CKR_OK)
307 		goto cleanup;
308 
309 	rv = C_DigestUpdate(hSession,
310 	    (CK_BYTE_PTR)netr_info->server_challenge.data, NETR_CRED_DATA_SZ);
311 	if (rv != CKR_OK)
312 		goto cleanup;
313 
314 	rv = C_DigestFinal(hSession, (CK_BYTE_PTR)md5digest, &diglen);
315 	if (rv != CKR_OK)
316 		goto cleanup;
317 
318 	rc = smb_auth_hmac_md5(md5digest, diglen, ntlmhash, SMBAUTH_HASH_SZ,
319 	    netr_info->session_key.key);
320 
321 	netr_info->session_key.len = NETR_SESSKEY128_SZ;
322 cleanup:
323 	(void) C_CloseSession(hSession);
324 	return (rc);
325 
326 }
327 /*
328  * netr_gen_skey64
329  *
330  * Generate a 64-bit session key from the client and server challenges.
331  * See "Session-Key Computation" section of MS-NRPC document.
332  *
333  * The algorithm is a two stage hash. For the first hash, the input is
334  * the combination of the client and server challenges, the key is
335  * the first 7 bytes of the password. The initial password is formed
336  * using the NT password hash on the local hostname in lower case.
337  * The result is stored in a temporary buffer.
338  *
339  *		input:	challenge
340  *		key:	passwd lower 7 bytes
341  *		output:	intermediate result
342  *
343  * For the second hash, the input is the result of the first hash and
344  * the key is the last 7 bytes of the password.
345  *
346  *		input:	result of first hash
347  *		key:	passwd upper 7 bytes
348  *		output:	session_key
349  *
350  * The final output should be the session key.
351  *
352  *		FYI: smb_auth_DES(output, key, input)
353  *
354  * If any difficulties occur using the cryptographic framework, the
355  * function returns SMBAUTH_FAILURE.  Otherwise SMBAUTH_SUCCESS is
356  * returned.
357  */
358 int
359 netr_gen_skey64(netr_info_t *netr_info)
360 {
361 	unsigned char md4hash[32];
362 	unsigned char buffer[8];
363 	DWORD data[2];
364 	DWORD *client_challenge;
365 	DWORD *server_challenge;
366 	int rc;
367 	DWORD le_data[2];
368 
369 	client_challenge = (DWORD *)(uintptr_t)&netr_info->client_challenge;
370 	server_challenge = (DWORD *)(uintptr_t)&netr_info->server_challenge;
371 	bzero(md4hash, 32);
372 
373 	/*
374 	 * We should check (netr_info->flags & NETR_FLG_INIT) and use
375 	 * the appropriate password but it isn't working yet.  So we
376 	 * always use the default one for now.
377 	 */
378 	bzero(netr_info->password, sizeof (netr_info->password));
379 	rc = smb_config_getstr(SMB_CI_MACHINE_PASSWD,
380 	    (char *)netr_info->password, sizeof (netr_info->password));
381 
382 	if ((rc != SMBD_SMF_OK) || *netr_info->password == '\0') {
383 		return (SMBAUTH_FAILURE);
384 	}
385 
386 	rc = smb_auth_ntlm_hash((char *)netr_info->password, md4hash);
387 
388 	if (rc != SMBAUTH_SUCCESS)
389 		return (SMBAUTH_FAILURE);
390 
391 	data[0] = LE_IN32(&client_challenge[0]) + LE_IN32(&server_challenge[0]);
392 	data[1] = LE_IN32(&client_challenge[1]) + LE_IN32(&server_challenge[1]);
393 	LE_OUT32(&le_data[0], data[0]);
394 	LE_OUT32(&le_data[1], data[1]);
395 	rc = smb_auth_DES(buffer, 8, md4hash, NETR_DESKEY_LEN,
396 	    (unsigned char *)le_data, 8);
397 
398 	if (rc != SMBAUTH_SUCCESS)
399 		return (rc);
400 
401 	netr_info->session_key.len = NETR_SESSKEY64_SZ;
402 	rc = smb_auth_DES(netr_info->session_key.key,
403 	    netr_info->session_key.len, &md4hash[9], NETR_DESKEY_LEN, buffer,
404 	    8);
405 
406 	return (rc);
407 }
408 
409 /*
410  * netr_gen_credentials
411  *
412  * Generate a set of credentials from a challenge and a session key.
413  * The algorithm is a two stage hash. For the first hash, the
414  * timestamp is added to the challenge and the result is stored in a
415  * temporary buffer:
416  *
417  *		input:	challenge (including timestamp)
418  *		key:	session_key
419  *		output:	intermediate result
420  *
421  * For the second hash, the input is the result of the first hash and
422  * a strange partial key is used:
423  *
424  *		input:	result of first hash
425  *		key:	funny partial key
426  *		output:	credentiails
427  *
428  * The final output should be an encrypted set of credentials.
429  *
430  *		FYI: smb_auth_DES(output, key, input)
431  *
432  * If any difficulties occur using the cryptographic framework, the
433  * function returns SMBAUTH_FAILURE.  Otherwise SMBAUTH_SUCCESS is
434  * returned.
435  */
436 int
437 netr_gen_credentials(BYTE *session_key, netr_cred_t *challenge,
438     DWORD timestamp, netr_cred_t *out_cred)
439 {
440 	unsigned char buffer[8];
441 	DWORD data[2];
442 	DWORD le_data[2];
443 	DWORD *p;
444 	int rc;
445 
446 	p = (DWORD *)(uintptr_t)challenge;
447 	data[0] = LE_IN32(&p[0]) + timestamp;
448 	data[1] = LE_IN32(&p[1]);
449 
450 	LE_OUT32(&le_data[0], data[0]);
451 	LE_OUT32(&le_data[1], data[1]);
452 
453 	if (smb_auth_DES(buffer, 8, session_key, NETR_DESKEY_LEN,
454 	    (unsigned char *)le_data, 8) != SMBAUTH_SUCCESS)
455 		return (SMBAUTH_FAILURE);
456 
457 	rc = smb_auth_DES(out_cred->data, 8, &session_key[NETR_DESKEY_LEN],
458 	    NETR_DESKEY_LEN, buffer, 8);
459 
460 	return (rc);
461 }
462 
463 /*
464  * netr_server_password_set
465  *
466  * Attempt to change the trust account password for this system.
467  *
468  * Note that this call may legitimately fail if the registry on the
469  * domain controller has been setup to deny attempts to change the
470  * trust account password. In this case we should just continue to
471  * use the original password.
472  *
473  * Possible status values:
474  *	NT_STATUS_ACCESS_DENIED
475  */
476 int
477 netr_server_password_set(mlsvc_handle_t *netr_handle, netr_info_t *netr_info)
478 {
479 	struct netr_PasswordSet  arg;
480 	int opnum;
481 	BYTE new_password[NETR_OWF_PASSWORD_SZ];
482 	char account_name[NETBIOS_NAME_SZ * 2];
483 
484 	bzero(&arg, sizeof (struct netr_PasswordSet));
485 	opnum = NETR_OPNUM_ServerPasswordSet;
486 
487 	(void) snprintf(account_name, sizeof (account_name), "%s$",
488 	    netr_info->hostname);
489 
490 	arg.servername = (unsigned char *)netr_info->server;
491 	arg.account_name = (unsigned char *)account_name;
492 	arg.account_type = NETR_WKSTA_TRUST_ACCOUNT_TYPE;
493 	arg.hostname = (unsigned char *)netr_info->hostname;
494 
495 	/*
496 	 * Set up the client side authenticator.
497 	 */
498 	if (netr_setup_authenticator(netr_info, &arg.auth, 0) !=
499 	    SMBAUTH_SUCCESS) {
500 		return (-1);
501 	}
502 
503 	/*
504 	 * Generate a new password from the old password.
505 	 */
506 	if (netr_gen_password(netr_info->session_key.key,
507 	    netr_info->password, new_password) == SMBAUTH_FAILURE) {
508 		return (-1);
509 	}
510 
511 	(void) memcpy(&arg.uas_new_password, &new_password,
512 	    NETR_OWF_PASSWORD_SZ);
513 
514 	if (ndr_rpc_call(netr_handle, opnum, &arg) != 0)
515 		return (-1);
516 
517 	if (arg.status != 0) {
518 		ndr_rpc_status(netr_handle, opnum, arg.status);
519 		ndr_rpc_release(netr_handle);
520 		return (-1);
521 	}
522 
523 	/*
524 	 * Check the returned credentials.  The server returns the new
525 	 * client credential rather than the new server credentiali,
526 	 * as documented elsewhere.
527 	 *
528 	 * Generate the new seed for the credential chain.  Increment
529 	 * the timestamp and add it to the client challenge.  Then we
530 	 * need to copy the challenge to the credential field in
531 	 * preparation for the next cycle.
532 	 */
533 	if (netr_validate_chain(netr_info, &arg.auth) == 0) {
534 		/*
535 		 * Save the new password.
536 		 */
537 		(void) memcpy(netr_info->password, new_password,
538 		    NETR_OWF_PASSWORD_SZ);
539 	}
540 
541 	ndr_rpc_release(netr_handle);
542 	return (0);
543 }
544 
545 /*
546  * netr_gen_password
547  *
548  * Generate a new pasword from the old password  and the session key.
549  * The algorithm is a two stage hash. The session key is used in the
550  * first hash but only part of the session key is used in the second
551  * hash.
552  *
553  * If any difficulties occur using the cryptographic framework, the
554  * function returns SMBAUTH_FAILURE.  Otherwise SMBAUTH_SUCCESS is
555  * returned.
556  */
557 static int
558 netr_gen_password(BYTE *session_key, BYTE *old_password, BYTE *new_password)
559 {
560 	int rv;
561 
562 	rv = smb_auth_DES(new_password, 8, session_key, NETR_DESKEY_LEN,
563 	    old_password, 8);
564 	if (rv != SMBAUTH_SUCCESS)
565 		return (rv);
566 
567 	rv = smb_auth_DES(&new_password[8], 8, &session_key[NETR_DESKEY_LEN],
568 	    NETR_DESKEY_LEN, &old_password[8], 8);
569 	return (rv);
570 }
571