krb5_wrap: Add MIT implmentation of smb_krb5_keyblock_init_contents()
[samba.git] / lib / krb5_wrap / krb5_samba.c
1 /*
2    Unix SMB/CIFS implementation.
3    simple kerberos5 routines for active directory
4    Copyright (C) Andrew Tridgell 2001
5    Copyright (C) Luke Howard 2002-2003
6    Copyright (C) Andrew Bartlett <abartlet@samba.org> 2005
7    Copyright (C) Guenther Deschner 2005-2009
8
9    This program is free software; you can redistribute it and/or modify
10    it under the terms of the GNU General Public License as published by
11    the Free Software Foundation; either version 3 of the License, or
12    (at your option) any later version.
13
14    This program is distributed in the hope that it will be useful,
15    but WITHOUT ANY WARRANTY; without even the implied warranty of
16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17    GNU General Public License for more details.
18
19    You should have received a copy of the GNU General Public License
20    along with this program.  If not, see <http://www.gnu.org/licenses/>.
21 */
22
23 #include "includes.h"
24 #include "system/filesys.h"
25 #include "krb5_samba.h"
26 #include "lib/util/asn1.h"
27
28 #ifdef HAVE_COM_ERR_H
29 #include <com_err.h>
30 #endif /* HAVE_COM_ERR_H */
31
32 #ifndef KRB5_AUTHDATA_WIN2K_PAC
33 #define KRB5_AUTHDATA_WIN2K_PAC 128
34 #endif
35
36 #ifndef KRB5_AUTHDATA_IF_RELEVANT
37 #define KRB5_AUTHDATA_IF_RELEVANT 1
38 #endif
39
40 #ifdef HAVE_KRB5
41
42 #define GSSAPI_CHECKSUM      0x8003             /* Checksum type value for Kerberos */
43 #define GSSAPI_BNDLENGTH     16                 /* Bind Length (rfc-1964 pg.3) */
44 #define GSSAPI_CHECKSUM_SIZE (4+GSSAPI_BNDLENGTH+4) /* Length of bind length,
45                                                         bind field, flags field. */
46 #define GSS_C_DELEG_FLAG 1
47
48 /* MIT krb5 1.7beta3 (in Ubuntu Karmic) is missing the prototype,
49    but still has the symbol */
50 #if !HAVE_DECL_KRB5_AUTH_CON_SET_REQ_CKSUMTYPE
51 krb5_error_code krb5_auth_con_set_req_cksumtype(
52         krb5_context     context,
53         krb5_auth_context      auth_context,
54         krb5_cksumtype     cksumtype);
55 #endif
56
57 #if !defined(SMB_MALLOC)
58 #undef malloc
59 #define SMB_MALLOC(s) malloc((s))
60 #endif
61
62 #ifndef SMB_STRDUP
63 #define SMB_STRDUP(s) strdup(s)
64 #endif
65
66 /**********************************************************
67  * MISSING FUNCTIONS
68  **********************************************************/
69
70 #if !defined(HAVE_KRB5_SET_DEFAULT_TGS_KTYPES)
71
72 #if defined(HAVE_KRB5_SET_DEFAULT_TGS_ENCTYPES)
73
74 /* With MIT kerberos, we should use krb5_set_default_tgs_enctypes in preference
75  * to krb5_set_default_tgs_ktypes. See
76  *         http://lists.samba.org/archive/samba-technical/2006-July/048271.html
77  *
78  * If the MIT libraries are not exporting internal symbols, we will end up in
79  * this branch, which is correct. Otherwise we will continue to use the
80  * internal symbol
81  */
82  krb5_error_code krb5_set_default_tgs_ktypes(krb5_context ctx, const krb5_enctype *enc)
83 {
84     return krb5_set_default_tgs_enctypes(ctx, enc);
85 }
86
87 #elif defined(HAVE_KRB5_SET_DEFAULT_IN_TKT_ETYPES)
88
89 /* Heimdal */
90  krb5_error_code krb5_set_default_tgs_ktypes(krb5_context ctx, const krb5_enctype *enc)
91 {
92         return krb5_set_default_in_tkt_etypes(ctx, enc);
93 }
94
95 #endif /* HAVE_KRB5_SET_DEFAULT_TGS_ENCTYPES */
96
97 #endif /* HAVE_KRB5_SET_DEFAULT_TGS_KTYPES */
98
99
100 #if defined(HAVE_KRB5_AUTH_CON_SETKEY) && !defined(HAVE_KRB5_AUTH_CON_SETUSERUSERKEY)
101 krb5_error_code krb5_auth_con_setuseruserkey(krb5_context context,
102                                              krb5_auth_context auth_context,
103                                              krb5_keyblock *keyblock)
104 {
105         return krb5_auth_con_setkey(context, auth_context, keyblock);
106 }
107 #endif
108
109 #if !defined(HAVE_KRB5_FREE_UNPARSED_NAME)
110 void krb5_free_unparsed_name(krb5_context context, char *val)
111 {
112         SAFE_FREE(val);
113 }
114 #endif
115
116 #if defined(HAVE_KRB5_PRINCIPAL_GET_COMP_STRING) && !defined(HAVE_KRB5_PRINC_COMPONENT)
117 const krb5_data *krb5_princ_component(krb5_context context,
118                                       krb5_principal principal, int i);
119
120 const krb5_data *krb5_princ_component(krb5_context context,
121                                       krb5_principal principal, int i)
122 {
123         static krb5_data kdata;
124
125         kdata.data = discard_const_p(char, krb5_principal_get_comp_string(context, principal, i));
126         kdata.length = strlen((const char *)kdata.data);
127         return &kdata;
128 }
129 #endif
130
131
132 /**********************************************************
133  * WRAPPING FUNCTIONS
134  **********************************************************/
135
136 #if defined(HAVE_ADDR_TYPE_IN_KRB5_ADDRESS)
137 /* HEIMDAL */
138
139 /**
140  * @brief Stores the address of a 'struct sockaddr_storage' a krb5_address
141  *
142  * @param[in]  paddr    A pointer to a 'struct sockaddr_storage to extract the
143  *                      address from.
144  *
145  * @param[out] pkaddr   A Kerberos address to store tha address in.
146  *
147  * @return True on success, false if an error occured.
148  */
149 bool smb_krb5_sockaddr_to_kaddr(struct sockaddr_storage *paddr,
150                                 krb5_address *pkaddr)
151 {
152         memset(pkaddr, '\0', sizeof(krb5_address));
153 #if defined(HAVE_IPV6) && defined(KRB5_ADDRESS_INET6)
154         if (paddr->ss_family == AF_INET6) {
155                 pkaddr->addr_type = KRB5_ADDRESS_INET6;
156                 pkaddr->address.length = sizeof(((struct sockaddr_in6 *)paddr)->sin6_addr);
157                 pkaddr->address.data = (char *)&(((struct sockaddr_in6 *)paddr)->sin6_addr);
158                 return true;
159         }
160 #endif
161         if (paddr->ss_family == AF_INET) {
162                 pkaddr->addr_type = KRB5_ADDRESS_INET;
163                 pkaddr->address.length = sizeof(((struct sockaddr_in *)paddr)->sin_addr);
164                 pkaddr->address.data = (char *)&(((struct sockaddr_in *)paddr)->sin_addr);
165                 return true;
166         }
167         return false;
168 }
169 #elif defined(HAVE_ADDRTYPE_IN_KRB5_ADDRESS)
170 /* MIT */
171
172 /**
173  * @brief Stores the address of a 'struct sockaddr_storage' a krb5_address
174  *
175  * @param[in]  paddr    A pointer to a 'struct sockaddr_storage to extract the
176  *                      address from.
177  *
178  * @param[in]  pkaddr A Kerberos address to store tha address in.
179  *
180  * @return True on success, false if an error occured.
181  */
182 bool smb_krb5_sockaddr_to_kaddr(struct sockaddr_storage *paddr,
183                                 krb5_address *pkaddr)
184 {
185         memset(pkaddr, '\0', sizeof(krb5_address));
186 #if defined(HAVE_IPV6) && defined(ADDRTYPE_INET6)
187         if (paddr->ss_family == AF_INET6) {
188                 pkaddr->addrtype = ADDRTYPE_INET6;
189                 pkaddr->length = sizeof(((struct sockaddr_in6 *)paddr)->sin6_addr);
190                 pkaddr->contents = (krb5_octet *)&(((struct sockaddr_in6 *)paddr)->sin6_addr);
191                 return true;
192         }
193 #endif
194         if (paddr->ss_family == AF_INET) {
195                 pkaddr->addrtype = ADDRTYPE_INET;
196                 pkaddr->length = sizeof(((struct sockaddr_in *)paddr)->sin_addr);
197                 pkaddr->contents = (krb5_octet *)&(((struct sockaddr_in *)paddr)->sin_addr);
198                 return true;
199         }
200         return false;
201 }
202 #else
203 #error UNKNOWN_ADDRTYPE
204 #endif
205
206 krb5_error_code smb_krb5_mk_error(krb5_context context,
207                                   krb5_error_code error_code,
208                                   const char *e_text,
209                                   krb5_data *e_data,
210                                   krb5_data *enc_err)
211 {
212         krb5_error_code code = EINVAL;
213 #ifdef SAMBA4_USES_HEIMDAL
214         code = krb5_mk_error(context,
215                              error_code,
216                              e_text,
217                              e_data,
218                              NULL, /* client */
219                              NULL, /* server */
220                              NULL, /* client_time */
221                              NULL, /* client_usec */
222                              enc_err);
223 #else
224         krb5_error dec_err = {
225                 .error = error_code,
226         };
227
228         if (e_text != NULL) {
229                 dec_err.text.length = strlen(e_text);
230                 dec_err.text.data = discard_const_p(char, e_text);
231         }
232         if (e_data != NULL) {
233                 dec_err.e_data = *e_data;
234         }
235
236         code = krb5_mk_error(context,
237                              &dec_err,
238                              enc_err);
239 #endif
240         return code;
241 }
242
243 /**
244 * @brief Create a keyblock based on input parameters
245 *
246 * @param context        The krb5_context
247 * @param host_princ     The krb5_principal to use
248 * @param salt           The optional salt, if omitted, salt is calculated with
249 *                       the provided principal.
250 * @param password       The krb5_data containing the password
251 * @param enctype        The krb5_enctype to use for the keyblock generation
252 * @param key            The returned krb5_keyblock, caller needs to free with
253 *                       krb5_free_keyblock().
254 *
255 * @return krb5_error_code
256 */
257 int smb_krb5_create_key_from_string(krb5_context context,
258                                     krb5_const_principal host_princ,
259                                     krb5_data *salt,
260                                     krb5_data *password,
261                                     krb5_enctype enctype,
262                                     krb5_keyblock *key)
263 {
264         int ret = 0;
265
266         if (host_princ == NULL && salt == NULL) {
267                 return -1;
268         }
269
270 #if defined(HAVE_KRB5_PRINCIPAL2SALT) && defined(HAVE_KRB5_C_STRING_TO_KEY)
271 {/* MIT */
272         krb5_data _salt;
273
274         if (salt == NULL) {
275                 ret = krb5_principal2salt(context, host_princ, &_salt);
276                 if (ret) {
277                         DEBUG(1,("krb5_principal2salt failed (%s)\n", error_message(ret)));
278                         return ret;
279                 }
280         } else {
281                 _salt = *salt;
282         }
283         ret = krb5_c_string_to_key(context, enctype, password, &_salt, key);
284         if (salt == NULL) {
285                 SAFE_FREE(_salt.data);
286         }
287 }
288 #elif defined(HAVE_KRB5_GET_PW_SALT) && defined(HAVE_KRB5_STRING_TO_KEY_SALT)
289 {/* Heimdal */
290         krb5_salt _salt;
291
292         if (salt == NULL) {
293                 ret = krb5_get_pw_salt(context, host_princ, &_salt);
294                 if (ret) {
295                         DEBUG(1,("krb5_get_pw_salt failed (%s)\n", error_message(ret)));
296                         return ret;
297                 }
298         } else {
299                 _salt.saltvalue = *salt;
300                 _salt.salttype = KRB5_PW_SALT;
301         }
302
303         ret = krb5_string_to_key_salt(context, enctype, (const char *)password->data, _salt, key);
304         if (salt == NULL) {
305                 krb5_free_salt(context, _salt);
306         }
307 }
308 #else
309 #error UNKNOWN_CREATE_KEY_FUNCTIONS
310 #endif
311         return ret;
312 }
313
314 /**
315 * @brief Create a salt for a given principal
316 *
317 * @param context        The initialized krb5_context
318 * @param host_princ     The krb5_principal to create the salt for
319 * @param psalt          A pointer to a krb5_data struct
320 *
321 * caller has to free the contents of psalt with smb_krb5_free_data_contents
322 * when function has succeeded
323 *
324 * @return krb5_error_code, returns 0 on success, error code otherwise
325 */
326
327 int smb_krb5_get_pw_salt(krb5_context context,
328                          krb5_const_principal host_princ,
329                          krb5_data *psalt)
330 #if defined(HAVE_KRB5_GET_PW_SALT)
331 /* Heimdal */
332 {
333         int ret;
334         krb5_salt salt;
335
336         ret = krb5_get_pw_salt(context, host_princ, &salt);
337         if (ret) {
338                 return ret;
339         }
340
341         psalt->data = salt.saltvalue.data;
342         psalt->length = salt.saltvalue.length;
343
344         return ret;
345 }
346 #elif defined(HAVE_KRB5_PRINCIPAL2SALT)
347 /* MIT */
348 {
349         return krb5_principal2salt(context, host_princ, psalt);
350 }
351 #else
352 #error UNKNOWN_SALT_FUNCTIONS
353 #endif
354
355 #if defined(HAVE_KRB5_GET_PERMITTED_ENCTYPES)
356 /**
357  * @brief Get a list of encryption types allowed for session keys
358  *
359  * @param[in]  context  The library context
360  *
361  * @param[in]  enctypes An allocated, zero-terminated list of encryption types
362  *
363  * This function returns an allocated list of encryption types allowed for
364  * session keys.
365  *
366  * Use free() to free the enctypes when it is no longer needed.
367  *
368  * @retval 0 Success; otherwise - Kerberos error codes
369  */
370 krb5_error_code smb_krb5_get_allowed_etypes(krb5_context context,
371                                             krb5_enctype **enctypes)
372 {
373         return krb5_get_permitted_enctypes(context, enctypes);
374 }
375 #elif defined(HAVE_KRB5_GET_DEFAULT_IN_TKT_ETYPES)
376 krb5_error_code smb_krb5_get_allowed_etypes(krb5_context context,
377                                             krb5_enctype **enctypes)
378 {
379 #ifdef HAVE_KRB5_PDU_NONE_DECL
380         return krb5_get_default_in_tkt_etypes(context, KRB5_PDU_NONE, enctypes);
381 #else
382         return krb5_get_default_in_tkt_etypes(context, enctypes);
383 #endif
384 }
385 #else
386 #error UNKNOWN_GET_ENCTYPES_FUNCTIONS
387 #endif
388
389 bool unwrap_edata_ntstatus(TALLOC_CTX *mem_ctx,
390                            DATA_BLOB *edata,
391                            DATA_BLOB *edata_out)
392 {
393         DATA_BLOB edata_contents;
394         ASN1_DATA *data;
395         int edata_type;
396
397         if (!edata->length) {
398                 return false;
399         }
400
401         data = asn1_init(mem_ctx);
402         if (data == NULL) {
403                 return false;
404         }
405
406         if (!asn1_load(data, *edata)) goto err;
407         if (!asn1_start_tag(data, ASN1_SEQUENCE(0))) goto err;
408         if (!asn1_start_tag(data, ASN1_CONTEXT(1))) goto err;
409         if (!asn1_read_Integer(data, &edata_type)) goto err;
410
411         if (edata_type != KRB5_PADATA_PW_SALT) {
412                 DEBUG(0,("edata is not of required type %d but of type %d\n",
413                         KRB5_PADATA_PW_SALT, edata_type));
414                 goto err;
415         }
416
417         if (!asn1_start_tag(data, ASN1_CONTEXT(2))) goto err;
418         if (!asn1_read_OctetString(data, talloc_tos(), &edata_contents)) goto err;
419         if (!asn1_end_tag(data)) goto err;
420         if (!asn1_end_tag(data)) goto err;
421         if (!asn1_end_tag(data)) goto err;
422         asn1_free(data);
423
424         *edata_out = data_blob_talloc(mem_ctx, edata_contents.data, edata_contents.length);
425
426         data_blob_free(&edata_contents);
427
428         return true;
429
430   err:
431
432         asn1_free(data);
433         return false;
434 }
435
436
437 /**************************************************************
438  krb5_parse_name that takes a UNIX charset.
439 **************************************************************/
440
441 krb5_error_code smb_krb5_parse_name(krb5_context context,
442                                 const char *name, /* in unix charset */
443                                 krb5_principal *principal)
444 {
445         krb5_error_code ret;
446         char *utf8_name;
447         size_t converted_size;
448         TALLOC_CTX *frame = talloc_stackframe();
449
450         if (!push_utf8_talloc(frame, &utf8_name, name, &converted_size)) {
451                 talloc_free(frame);
452                 return ENOMEM;
453         }
454
455         ret = krb5_parse_name(context, utf8_name, principal);
456         TALLOC_FREE(frame);
457         return ret;
458 }
459
460 /**************************************************************
461  krb5_parse_name that returns a UNIX charset name. Must
462  be freed with talloc_free() call.
463 **************************************************************/
464
465 krb5_error_code smb_krb5_unparse_name(TALLOC_CTX *mem_ctx,
466                                       krb5_context context,
467                                       krb5_const_principal principal,
468                                       char **unix_name)
469 {
470         krb5_error_code ret;
471         char *utf8_name;
472         size_t converted_size;
473
474         *unix_name = NULL;
475         ret = krb5_unparse_name(context, principal, &utf8_name);
476         if (ret) {
477                 return ret;
478         }
479
480         if (!pull_utf8_talloc(mem_ctx, unix_name, utf8_name, &converted_size)) {
481                 krb5_free_unparsed_name(context, utf8_name);
482                 return ENOMEM;
483         }
484         krb5_free_unparsed_name(context, utf8_name);
485         return 0;
486 }
487
488 krb5_error_code smb_krb5_parse_name_norealm(krb5_context context, 
489                                             const char *name, 
490                                             krb5_principal *principal)
491 {
492         /* we are cheating here because parse_name will in fact set the realm.
493          * We don't care as the only caller of smb_krb5_parse_name_norealm
494          * ignores the realm anyway when calling
495          * smb_krb5_principal_compare_any_realm later - Guenther */
496
497         return smb_krb5_parse_name(context, name, principal);
498 }
499
500 bool smb_krb5_principal_compare_any_realm(krb5_context context, 
501                                           krb5_const_principal princ1, 
502                                           krb5_const_principal princ2)
503 {
504         return krb5_principal_compare_any_realm(context, princ1, princ2);
505 }
506
507 /**
508  * @brief Free the contents of a krb5_data structure and zero the data field.
509  *
510  * @param[in]  context  The krb5 context
511  *
512  * @param[in]  pdata    The data structure to free contents of
513  *
514  * This function frees the contents, not the structure itself.
515  */
516 void smb_krb5_free_data_contents(krb5_context context, krb5_data *pdata)
517 {
518 #if defined(HAVE_KRB5_FREE_DATA_CONTENTS)
519         if (pdata->data) {
520                 krb5_free_data_contents(context, pdata);
521         }
522 #elif defined(HAVE_KRB5_DATA_FREE)
523         krb5_data_free(context, pdata);
524 #else
525         SAFE_FREE(pdata->data);
526 #endif
527 }
528
529 /*
530  * @brief copy a buffer into a krb5_data struct
531  *
532  * @param[in] p                 The krb5_data
533  * @param[in] data              The data to copy
534  * @param[in] length            The length of the data to copy
535  * @return krb5_error_code
536  *
537  * Caller has to free krb5_data with smb_krb5_free_data_contents().
538  */
539 krb5_error_code smb_krb5_copy_data_contents(krb5_data *p,
540                                             const void *data,
541                                             size_t len)
542 {
543 #if defined(HAVE_KRB5_DATA_COPY)
544         return krb5_data_copy(p, data, len);
545 #else
546         if (len) {
547                 p->data = malloc(len);
548                 if (p->data == NULL) {
549                         return ENOMEM;
550                 }
551                 memmove(p->data, data, len);
552         } else {
553                 p->data = NULL;
554         }
555         p->length = len;
556         p->magic = KV5M_DATA;
557         return 0;
558 #endif
559 }
560
561 bool smb_krb5_get_smb_session_key(TALLOC_CTX *mem_ctx,
562                                   krb5_context context,
563                                   krb5_auth_context auth_context,
564                                   DATA_BLOB *session_key,
565                                   bool remote)
566 {
567         krb5_keyblock *skey = NULL;
568         krb5_error_code err = 0;
569         bool ret = false;
570
571         if (remote) {
572 #ifdef HAVE_KRB5_AUTH_CON_GETRECVSUBKEY
573                 err = krb5_auth_con_getrecvsubkey(context,
574                                                   auth_context,
575                                                   &skey);
576 #else /* HAVE_KRB5_AUTH_CON_GETRECVSUBKEY */
577                 err = krb5_auth_con_getremotesubkey(context,
578                                                     auth_context, &skey);
579 #endif /* HAVE_KRB5_AUTH_CON_GETRECVSUBKEY */
580         } else {
581 #ifdef HAVE_KRB5_AUTH_CON_GETSENDSUBKEY
582                 err = krb5_auth_con_getsendsubkey(context,
583                                                   auth_context,
584                                                   &skey);
585 #else /* HAVE_KRB5_AUTH_CON_GETSENDSUBKEY */
586                 err = krb5_auth_con_getlocalsubkey(context,
587                                                    auth_context, &skey);
588 #endif /* HAVE_KRB5_AUTH_CON_GETSENDSUBKEY */
589         }
590
591         if (err || skey == NULL) {
592                 DEBUG(10, ("KRB5 error getting session key %d\n", err));
593                 goto done;
594         }
595
596         DEBUG(10, ("Got KRB5 session key of length %d\n",
597                    (int)KRB5_KEY_LENGTH(skey)));
598
599         *session_key = data_blob_talloc(mem_ctx,
600                                          KRB5_KEY_DATA(skey),
601                                          KRB5_KEY_LENGTH(skey));
602         dump_data_pw("KRB5 Session Key:\n",
603                      session_key->data,
604                      session_key->length);
605
606         ret = true;
607
608 done:
609         if (skey) {
610                 krb5_free_keyblock(context, skey);
611         }
612
613         return ret;
614 }
615
616
617 /**
618  * @brief Get talloced string component of a principal
619  *
620  * @param[in] mem_ctx           The TALLOC_CTX
621  * @param[in] context           The krb5_context
622  * @param[in] principal         The principal
623  * @param[in] component         The component
624  * @return string component
625  *
626  * Caller must talloc_free if the return value is not NULL.
627  *
628  */
629 char *smb_krb5_principal_get_comp_string(TALLOC_CTX *mem_ctx,
630                                          krb5_context context,
631                                          krb5_const_principal principal,
632                                          unsigned int component)
633 {
634 #if defined(HAVE_KRB5_PRINCIPAL_GET_COMP_STRING)
635         return talloc_strdup(mem_ctx, krb5_principal_get_comp_string(context, principal, component));
636 #else
637         krb5_data *data;
638
639         if (component >= krb5_princ_size(context, principal)) {
640                 return NULL;
641         }
642
643         data = krb5_princ_component(context, principal, component);
644         if (data == NULL) {
645                 return NULL;
646         }
647
648         return talloc_strndup(mem_ctx, data->data, data->length);
649 #endif
650 }
651
652 /**
653  * @brief
654  *
655  * @param[in]  ccache_string A string pointing to the cache to renew the ticket
656  *                           (e.g. FILE:/tmp/krb5cc_0) or NULL. If the principal
657  *                           ccache has not been specified, the default ccache
658  *                           will be used.
659  *
660  * @param[in]  client_string The client principal string (e.g. user@SAMBA.SITE)
661  *                           or NULL. If the principal string has not been
662  *                           specified, the principal from the ccache will be
663  *                           retrieved.
664  *
665  * @param[in]  service_string The service ticket string
666  *                            (e.g. krbtgt/SAMBA.SITE@SAMBA.SITE) or NULL. If
667  *                            the sevice ticket is specified, it is parsed (
668  *                            with the realm part ignored) and used as the
669  *                            server principal of the credential. Otherwise
670  *                            the ticket-granting service is used.
671  *
672  * @param[in]  expire_time    A pointer to store the credentials end time or
673  *                            NULL.
674  *
675  * @return 0 on Succes, a Kerberos error code otherwise.
676  */
677 krb5_error_code smb_krb5_renew_ticket(const char *ccache_string,
678                                       const char *client_string,
679                                       const char *service_string,
680                                       time_t *expire_time)
681 {
682         krb5_error_code ret;
683         krb5_context context = NULL;
684         krb5_ccache ccache = NULL;
685         krb5_principal client = NULL;
686         krb5_creds creds, creds_in;
687
688         ZERO_STRUCT(creds);
689         ZERO_STRUCT(creds_in);
690
691         initialize_krb5_error_table();
692         ret = krb5_init_context(&context);
693         if (ret) {
694                 goto done;
695         }
696
697         if (!ccache_string) {
698                 ccache_string = krb5_cc_default_name(context);
699         }
700
701         if (!ccache_string) {
702                 ret = EINVAL;
703                 goto done;
704         }
705
706         DEBUG(10,("smb_krb5_renew_ticket: using %s as ccache\n", ccache_string));
707
708         /* FIXME: we should not fall back to defaults */
709         ret = krb5_cc_resolve(context, discard_const_p(char, ccache_string), &ccache);
710         if (ret) {
711                 goto done;
712         }
713
714         if (client_string) {
715                 ret = smb_krb5_parse_name(context, client_string, &client);
716                 if (ret) {
717                         goto done;
718                 }
719         } else {
720                 ret = krb5_cc_get_principal(context, ccache, &client);
721                 if (ret) {
722                         goto done;
723                 }
724         }
725
726         ret = krb5_get_renewed_creds(context, &creds, client, ccache, discard_const_p(char, service_string));
727         if (ret) {
728                 DEBUG(10,("smb_krb5_renew_ticket: krb5_get_kdc_cred failed: %s\n", error_message(ret)));
729                 goto done;
730         }
731
732         /* hm, doesn't that create a new one if the old one wasn't there? - Guenther */
733         ret = krb5_cc_initialize(context, ccache, client);
734         if (ret) {
735                 goto done;
736         }
737
738         ret = krb5_cc_store_cred(context, ccache, &creds);
739
740         if (expire_time) {
741                 *expire_time = (time_t) creds.times.endtime;
742         }
743
744 done:
745         krb5_free_cred_contents(context, &creds_in);
746         krb5_free_cred_contents(context, &creds);
747
748         if (client) {
749                 krb5_free_principal(context, client);
750         }
751         if (ccache) {
752                 krb5_cc_close(context, ccache);
753         }
754         if (context) {
755                 krb5_free_context(context);
756         }
757
758         return ret;
759 }
760
761 /**
762  * @brief Free the data stored in an smb_krb5_addresses structure.
763  *
764  * @param[in]  context  The library context
765  *
766  * @param[in]  addr     The address structure to free.
767  *
768  * @return 0 on success, a Kerberos error code otherwise.
769  */
770 krb5_error_code smb_krb5_free_addresses(krb5_context context,
771                                         smb_krb5_addresses *addr)
772 {
773         krb5_error_code ret = 0;
774         if (addr == NULL) {
775                 return ret;
776         }
777 #if defined(HAVE_MAGIC_IN_KRB5_ADDRESS) && defined(HAVE_ADDRTYPE_IN_KRB5_ADDRESS) /* MIT */
778         krb5_free_addresses(context, addr->addrs);
779 #elif defined(HAVE_ADDR_TYPE_IN_KRB5_ADDRESS) /* Heimdal */
780         ret = krb5_free_addresses(context, addr->addrs);
781         SAFE_FREE(addr->addrs);
782 #endif
783         SAFE_FREE(addr);
784         addr = NULL;
785         return ret;
786 }
787
788 #define MAX_NETBIOSNAME_LEN 16
789
790 /**
791  * @brief Add a netbios name to the array of addresses
792  *
793  * @param[in]  kerb_addr A pointer to the smb_krb5_addresses to add the
794  *                       netbios name to.
795  *
796  * @param[in]  netbios_name The netbios name to add.
797  *
798  * @return 0 on success, a Kerberos error code otherwise.
799  */
800 krb5_error_code smb_krb5_gen_netbios_krb5_address(smb_krb5_addresses **kerb_addr,
801                                                    const char *netbios_name)
802 {
803         krb5_error_code ret = 0;
804         char buf[MAX_NETBIOSNAME_LEN];
805         int len;
806 #if defined(HAVE_MAGIC_IN_KRB5_ADDRESS) && defined(HAVE_ADDRTYPE_IN_KRB5_ADDRESS) /* MIT */
807         krb5_address **addrs = NULL;
808 #elif defined(HAVE_ADDR_TYPE_IN_KRB5_ADDRESS) /* Heimdal */
809         krb5_addresses *addrs = NULL;
810 #endif
811
812         *kerb_addr = (smb_krb5_addresses *)SMB_MALLOC(sizeof(smb_krb5_addresses));
813         if (*kerb_addr == NULL) {
814                 return ENOMEM;
815         }
816
817         /* temporarily duplicate put_name() code here to avoid dependency
818          * issues for a 5 lines function */
819         len = strlen(netbios_name);
820         memcpy(buf, netbios_name,
821                 (len < MAX_NETBIOSNAME_LEN) ? len : MAX_NETBIOSNAME_LEN - 1);
822         if (len < MAX_NETBIOSNAME_LEN - 1) {
823                 memset(buf + len, ' ', MAX_NETBIOSNAME_LEN - 1 - len);
824         }
825         buf[MAX_NETBIOSNAME_LEN - 1] = 0x20;
826
827 #if defined(HAVE_MAGIC_IN_KRB5_ADDRESS) && defined(HAVE_ADDRTYPE_IN_KRB5_ADDRESS) /* MIT */
828         {
829                 int num_addr = 2;
830
831                 addrs = (krb5_address **)SMB_MALLOC(sizeof(krb5_address *) * num_addr);
832                 if (addrs == NULL) {
833                         SAFE_FREE(*kerb_addr);
834                         return ENOMEM;
835                 }
836
837                 memset(addrs, 0, sizeof(krb5_address *) * num_addr);
838
839                 addrs[0] = (krb5_address *)SMB_MALLOC(sizeof(krb5_address));
840                 if (addrs[0] == NULL) {
841                         SAFE_FREE(addrs);
842                         SAFE_FREE(*kerb_addr);
843                         return ENOMEM;
844                 }
845
846                 addrs[0]->magic = KV5M_ADDRESS;
847                 addrs[0]->addrtype = KRB5_ADDR_NETBIOS;
848                 addrs[0]->length = MAX_NETBIOSNAME_LEN;
849                 addrs[0]->contents = (unsigned char *)SMB_MALLOC(addrs[0]->length);
850                 if (addrs[0]->contents == NULL) {
851                         SAFE_FREE(addrs[0]);
852                         SAFE_FREE(addrs);
853                         SAFE_FREE(*kerb_addr);
854                         return ENOMEM;
855                 }
856
857                 memcpy(addrs[0]->contents, buf, addrs[0]->length);
858
859                 addrs[1] = NULL;
860         }
861 #elif defined(HAVE_ADDR_TYPE_IN_KRB5_ADDRESS) /* Heimdal */
862         {
863                 addrs = (krb5_addresses *)SMB_MALLOC(sizeof(krb5_addresses));
864                 if (addrs == NULL) {
865                         SAFE_FREE(*kerb_addr);
866                         return ENOMEM;
867                 }
868
869                 memset(addrs, 0, sizeof(krb5_addresses));
870
871                 addrs->len = 1;
872                 addrs->val = (krb5_address *)SMB_MALLOC(sizeof(krb5_address));
873                 if (addrs->val == NULL) {
874                         SAFE_FREE(addrs);
875                         SAFE_FREE(kerb_addr);
876                         return ENOMEM;
877                 }
878
879                 addrs->val[0].addr_type = KRB5_ADDR_NETBIOS;
880                 addrs->val[0].address.length = MAX_NETBIOSNAME_LEN;
881                 addrs->val[0].address.data = (unsigned char *)SMB_MALLOC(addrs->val[0].address.length);
882                 if (addrs->val[0].address.data == NULL) {
883                         SAFE_FREE(addrs->val);
884                         SAFE_FREE(addrs);
885                         SAFE_FREE(*kerb_addr);
886                         return ENOMEM;
887                 }
888
889                 memcpy(addrs->val[0].address.data, buf, addrs->val[0].address.length);
890         }
891 #else
892 #error UNKNOWN_KRB5_ADDRESS_FORMAT
893 #endif
894         (*kerb_addr)->addrs = addrs;
895
896         return ret;
897 }
898
899 /**
900  * @brief Get the enctype from a key table entry
901  *
902  * @param[in]  kt_entry Key table entry to get the enctype from.
903  *
904  * @return The enctype from the entry.
905  */
906 krb5_enctype smb_krb5_kt_get_enctype_from_entry(krb5_keytab_entry *kt_entry)
907 {
908         return KRB5_KEY_TYPE(KRB5_KT_KEY(kt_entry));
909 }
910
911 /**
912  * @brief Free the contents of a key table entry.
913  *
914  * @param[in]  context The library context.
915  *
916  * @param[in]  kt_entry The key table entry to free the contents of.
917  *
918  * @return 0 on success, a Kerberos error code otherwise.
919  *
920  * The pointer itself is not freed.
921  */
922 krb5_error_code smb_krb5_kt_free_entry(krb5_context context,
923                                         krb5_keytab_entry *kt_entry)
924 {
925 /* Try krb5_free_keytab_entry_contents first, since
926  * MIT Kerberos >= 1.7 has both krb5_free_keytab_entry_contents and
927  * krb5_kt_free_entry but only has a prototype for the first, while the
928  * second is considered private.
929  */
930 #if defined(HAVE_KRB5_FREE_KEYTAB_ENTRY_CONTENTS)
931         return krb5_free_keytab_entry_contents(context, kt_entry);
932 #elif defined(HAVE_KRB5_KT_FREE_ENTRY)
933         return krb5_kt_free_entry(context, kt_entry);
934 #else
935 #error UNKNOWN_KT_FREE_FUNCTION
936 #endif
937 }
938
939
940 /**
941  * @brief Convert an encryption type to a string.
942  *
943  * @param[in]  context The library context.
944  *
945  * @param[in]  enctype The encryption type.
946  *
947  * @param[in]  etype_s A pointer to store the allocated encryption type as a
948  *                     string.
949  *
950  * @return 0 on success, a Kerberos error code otherwise.
951  *
952  * The caller needs to free the allocated string etype_s.
953  */
954 krb5_error_code smb_krb5_enctype_to_string(krb5_context context,
955                                            krb5_enctype enctype,
956                                            char **etype_s)
957 {
958 #ifdef HAVE_KRB5_ENCTYPE_TO_STRING_WITH_KRB5_CONTEXT_ARG
959         return krb5_enctype_to_string(context, enctype, etype_s); /* Heimdal */
960 #elif defined(HAVE_KRB5_ENCTYPE_TO_STRING_WITH_SIZE_T_ARG)
961         char buf[256];
962         krb5_error_code ret = krb5_enctype_to_string(enctype, buf, 256); /* MIT */
963         if (ret) {
964                 return ret;
965         }
966         *etype_s = SMB_STRDUP(buf);
967         if (!*etype_s) {
968                 return ENOMEM;
969         }
970         return ret;
971 #else
972 #error UNKNOWN_KRB5_ENCTYPE_TO_STRING_FUNCTION
973 #endif
974 }
975
976 /* This MAX_NAME_LEN is a constant defined in krb5.h */
977 #ifndef MAX_KEYTAB_NAME_LEN
978 #define MAX_KEYTAB_NAME_LEN 1100
979 #endif
980
981 /**
982  * @brief Open a key table readonly or with readwrite access.
983  *
984  * Allows to use a different keytab than the default one using a relative
985  * path to the keytab.
986  *
987  * @param[in]  context  The library context
988  *
989  * @param[in]  keytab_name_req The path to the key table.
990  *
991  * @param[in]  write_access Open with readwrite access.
992  *
993  * @param[in]  keytab A pointer o the opended key table.
994  *
995  * The keytab pointer should be freed using krb5_kt_close().
996  *
997  * @return 0 on success, a Kerberos error code otherwise.
998  */
999 krb5_error_code smb_krb5_kt_open_relative(krb5_context context,
1000                                           const char *keytab_name_req,
1001                                           bool write_access,
1002                                           krb5_keytab *keytab)
1003 {
1004         krb5_error_code ret = 0;
1005         TALLOC_CTX *mem_ctx;
1006         char keytab_string[MAX_KEYTAB_NAME_LEN];
1007         char *kt_str = NULL;
1008         bool found_valid_name = false;
1009         const char *pragma = "FILE";
1010         const char *tmp = NULL;
1011
1012         if (!write_access && !keytab_name_req) {
1013                 /* caller just wants to read the default keytab readonly, so be it */
1014                 return krb5_kt_default(context, keytab);
1015         }
1016
1017         mem_ctx = talloc_init("smb_krb5_open_keytab");
1018         if (!mem_ctx) {
1019                 return ENOMEM;
1020         }
1021
1022 #ifdef HAVE_WRFILE_KEYTAB
1023         if (write_access) {
1024                 pragma = "WRFILE";
1025         }
1026 #endif
1027
1028         if (keytab_name_req) {
1029
1030                 if (strlen(keytab_name_req) > MAX_KEYTAB_NAME_LEN) {
1031                         ret = KRB5_CONFIG_NOTENUFSPACE;
1032                         goto out;
1033                 }
1034
1035                 if ((strncmp(keytab_name_req, "WRFILE:/", 8) == 0) ||
1036                     (strncmp(keytab_name_req, "FILE:/", 6) == 0)) {
1037                         tmp = keytab_name_req;
1038                         goto resolve;
1039                 }
1040
1041                 tmp = talloc_asprintf(mem_ctx, "%s:%s", pragma, keytab_name_req);
1042                 if (!tmp) {
1043                         ret = ENOMEM;
1044                         goto out;
1045                 }
1046
1047                 goto resolve;
1048         }
1049
1050         /* we need to handle more complex keytab_strings, like:
1051          * "ANY:FILE:/etc/krb5.keytab,krb4:/etc/srvtab" */
1052
1053         ret = krb5_kt_default_name(context, &keytab_string[0], MAX_KEYTAB_NAME_LEN - 2);
1054         if (ret) {
1055                 goto out;
1056         }
1057
1058         DEBUG(10,("smb_krb5_open_keytab: krb5_kt_default_name returned %s\n", keytab_string));
1059
1060         tmp = talloc_strdup(mem_ctx, keytab_string);
1061         if (!tmp) {
1062                 ret = ENOMEM;
1063                 goto out;
1064         }
1065
1066         if (strncmp(tmp, "ANY:", 4) == 0) {
1067                 tmp += 4;
1068         }
1069
1070         memset(&keytab_string, '\0', sizeof(keytab_string));
1071
1072         while (next_token_talloc(mem_ctx, &tmp, &kt_str, ",")) {
1073                 if (strncmp(kt_str, "WRFILE:", 7) == 0) {
1074                         found_valid_name = true;
1075                         tmp = kt_str;
1076                         tmp += 7;
1077                 }
1078
1079                 if (strncmp(kt_str, "FILE:", 5) == 0) {
1080                         found_valid_name = true;
1081                         tmp = kt_str;
1082                         tmp += 5;
1083                 }
1084
1085                 if (tmp[0] == '/') {
1086                         /* Treat as a FILE: keytab definition. */
1087                         found_valid_name = true;
1088                 }
1089
1090                 if (found_valid_name) {
1091                         if (tmp[0] != '/') {
1092                                 ret = KRB5_KT_BADNAME;
1093                                 goto out;
1094                         }
1095
1096                         tmp = talloc_asprintf(mem_ctx, "%s:%s", pragma, tmp);
1097                         if (!tmp) {
1098                                 ret = ENOMEM;
1099                                 goto out;
1100                         }
1101                         break;
1102                 }
1103         }
1104
1105         if (!found_valid_name) {
1106                 ret = KRB5_KT_UNKNOWN_TYPE;
1107                 goto out;
1108         }
1109
1110 resolve:
1111         DEBUG(10,("smb_krb5_open_keytab: resolving: %s\n", tmp));
1112         ret = krb5_kt_resolve(context, tmp, keytab);
1113
1114 out:
1115         TALLOC_FREE(mem_ctx);
1116         return ret;
1117 }
1118
1119 /**
1120  * @brief Open a key table readonly or with readwrite access.
1121  *
1122  * Allows to use a different keytab than the default one. The path needs to be
1123  * an absolute path or an error will be returned.
1124  *
1125  * @param[in]  context  The library context
1126  *
1127  * @param[in]  keytab_name_req The path to the key table.
1128  *
1129  * @param[in]  write_access Open with readwrite access.
1130  *
1131  * @param[in]  keytab A pointer o the opended key table.
1132  *
1133  * The keytab pointer should be freed using krb5_kt_close().
1134  *
1135  * @return 0 on success, a Kerberos error code otherwise.
1136  */
1137 krb5_error_code smb_krb5_kt_open(krb5_context context,
1138                                  const char *keytab_name_req,
1139                                  bool write_access,
1140                                  krb5_keytab *keytab)
1141 {
1142         if (keytab_name_req != NULL) {
1143                 if (keytab_name_req[0] != '/') {
1144                         return KRB5_KT_BADNAME;
1145                 }
1146         }
1147
1148         return smb_krb5_kt_open_relative(context,
1149                                          keytab_name_req,
1150                                          write_access,
1151                                          keytab);
1152 }
1153
1154 /**
1155  * @brief Get a key table name.
1156  *
1157  * @param[in]  mem_ctx The talloc context to use for allocation.
1158  *
1159  * @param[in]  context The library context.
1160  *
1161  * @param[in]  keytab The key table to get the name from.
1162  *
1163  * @param[in]  keytab_name A talloc'ed string of the key table name.
1164  *
1165  * The talloc'ed name string needs to be freed with talloc_free().
1166  *
1167  * @return 0 on success, a Kerberos error code otherwise.
1168  */
1169 krb5_error_code smb_krb5_kt_get_name(TALLOC_CTX *mem_ctx,
1170                                      krb5_context context,
1171                                      krb5_keytab keytab,
1172                                      const char **keytab_name)
1173 {
1174         char keytab_string[MAX_KEYTAB_NAME_LEN];
1175         krb5_error_code ret = 0;
1176
1177         ret = krb5_kt_get_name(context, keytab,
1178                                keytab_string, MAX_KEYTAB_NAME_LEN - 2);
1179         if (ret) {
1180                 return ret;
1181         }
1182
1183         *keytab_name = talloc_strdup(mem_ctx, keytab_string);
1184         if (!*keytab_name) {
1185                 return ENOMEM;
1186         }
1187
1188         return ret;
1189 }
1190
1191 /**
1192  * @brief Seek and delete old entries in a keytab based on the passed
1193  *        principal.
1194  *
1195  * @param[in]  context       The KRB5 context to use.
1196  *
1197  * @param[in]  keytab        The keytab to operate on.
1198  *
1199  * @param[in]  kvno          The kvnco to use.
1200  *
1201  * @param[in]  princ_s       The principal as a string to search for.
1202  *
1203  * @param[in]  princ         The principal as a krb5_principal to search for.
1204  *
1205  * @param[in]  flush         Weather to flush the complete keytab.
1206  *
1207  * @param[in]  keep_old_entries Keep the entry with the previous kvno.
1208  *
1209  * @retval 0 on Sucess
1210  *
1211  * @return An appropriate KRB5 error code.
1212  */
1213 krb5_error_code smb_krb5_kt_seek_and_delete_old_entries(krb5_context context,
1214                                                         krb5_keytab keytab,
1215                                                         krb5_kvno kvno,
1216                                                         krb5_enctype enctype,
1217                                                         const char *princ_s,
1218                                                         krb5_principal princ,
1219                                                         bool flush,
1220                                                         bool keep_old_entries)
1221 {
1222         krb5_error_code ret;
1223         krb5_kt_cursor cursor;
1224         krb5_kt_cursor zero_csr;
1225         krb5_keytab_entry kt_entry;
1226         krb5_keytab_entry zero_kt_entry;
1227         char *ktprinc = NULL;
1228         krb5_kvno old_kvno = kvno - 1;
1229         TALLOC_CTX *tmp_ctx;
1230
1231         ZERO_STRUCT(cursor);
1232         ZERO_STRUCT(zero_csr);
1233         ZERO_STRUCT(kt_entry);
1234         ZERO_STRUCT(zero_kt_entry);
1235
1236         ret = krb5_kt_start_seq_get(context, keytab, &cursor);
1237         if (ret == KRB5_KT_END || ret == ENOENT ) {
1238                 /* no entries */
1239                 return 0;
1240         }
1241
1242         tmp_ctx = talloc_new(NULL);
1243         if (tmp_ctx == NULL) {
1244                 return ENOMEM;
1245         }
1246
1247         DEBUG(3, (__location__ ": Will try to delete old keytab entries\n"));
1248         while (!krb5_kt_next_entry(context, keytab, &kt_entry, &cursor)) {
1249                 bool name_ok = false;
1250                 krb5_enctype kt_entry_enctype =
1251                         smb_krb5_kt_get_enctype_from_entry(&kt_entry);
1252
1253                 if (!flush && (princ_s != NULL)) {
1254                         ret = smb_krb5_unparse_name(tmp_ctx, context,
1255                                                     kt_entry.principal,
1256                                                     &ktprinc);
1257                         if (ret) {
1258                                 DEBUG(1, (__location__
1259                                           ": smb_krb5_unparse_name failed "
1260                                           "(%s)\n", error_message(ret)));
1261                                 goto out;
1262                         }
1263
1264 #ifdef HAVE_KRB5_KT_COMPARE
1265                         name_ok = krb5_kt_compare(context, &kt_entry,
1266                                                   princ, 0, 0);
1267 #else
1268                         name_ok = (strcmp(ktprinc, princ_s) == 0);
1269 #endif
1270
1271                         if (!name_ok) {
1272                                 DEBUG(10, (__location__ ": ignoring keytab "
1273                                            "entry principal %s, kvno = %d\n",
1274                                            ktprinc, kt_entry.vno));
1275
1276                                 /* Not a match,
1277                                  * just free this entry and continue. */
1278                                 ret = smb_krb5_kt_free_entry(context,
1279                                                              &kt_entry);
1280                                 ZERO_STRUCT(kt_entry);
1281                                 if (ret) {
1282                                         DEBUG(1, (__location__
1283                                                   ": smb_krb5_kt_free_entry "
1284                                                   "failed (%s)\n",
1285                                                   error_message(ret)));
1286                                         goto out;
1287                                 }
1288
1289                                 TALLOC_FREE(ktprinc);
1290                                 continue;
1291                         }
1292
1293                         TALLOC_FREE(ktprinc);
1294                 }
1295
1296                 /*------------------------------------------------------------
1297                  * Save the entries with kvno - 1. This is what microsoft does
1298                  * to allow people with existing sessions that have kvno - 1
1299                  * to still work. Otherwise, when the password for the machine
1300                  * changes, all kerberizied sessions will 'break' until either
1301                  * the client reboots or the client's session key expires and
1302                  * they get a new session ticket with the new kvno.
1303                  * Some keytab files only store the kvno in 8bits, limit
1304                  * the compare accordingly.
1305                  */
1306
1307                 if (!flush && ((kt_entry.vno & 0xff) == (old_kvno & 0xff))) {
1308                         DEBUG(5, (__location__ ": Saving previous (kvno %d) "
1309                                   "entry for principal: %s.\n",
1310                                   old_kvno, princ_s));
1311                         continue;
1312                 }
1313
1314                 if (keep_old_entries) {
1315                         DEBUG(5, (__location__ ": Saving old (kvno %d) "
1316                                   "entry for principal: %s.\n",
1317                                   kvno, princ_s));
1318                         continue;
1319                 }
1320
1321                 if (!flush &&
1322                     (kt_entry.vno == kvno) &&
1323                     (kt_entry_enctype != enctype))
1324                 {
1325                         DEBUG(5, (__location__ ": Saving entry with kvno [%d] "
1326                                   "enctype [%d] for principal: %s.\n",
1327                                   kvno, kt_entry_enctype, princ_s));
1328                         continue;
1329                 }
1330
1331                 DEBUG(5, (__location__ ": Found old entry for principal: %s "
1332                           "(kvno %d) - trying to remove it.\n",
1333                           princ_s, kt_entry.vno));
1334
1335                 ret = krb5_kt_end_seq_get(context, keytab, &cursor);
1336                 ZERO_STRUCT(cursor);
1337                 if (ret) {
1338                         DEBUG(1, (__location__ ": krb5_kt_end_seq_get() "
1339                                   "failed (%s)\n", error_message(ret)));
1340                         goto out;
1341                 }
1342                 ret = krb5_kt_remove_entry(context, keytab, &kt_entry);
1343                 if (ret) {
1344                         DEBUG(1, (__location__ ": krb5_kt_remove_entry() "
1345                                   "failed (%s)\n", error_message(ret)));
1346                         goto out;
1347                 }
1348
1349                 DEBUG(5, (__location__ ": removed old entry for principal: "
1350                           "%s (kvno %d).\n", princ_s, kt_entry.vno));
1351
1352                 ret = krb5_kt_start_seq_get(context, keytab, &cursor);
1353                 if (ret) {
1354                         DEBUG(1, (__location__ ": krb5_kt_start_seq() failed "
1355                                   "(%s)\n", error_message(ret)));
1356                         goto out;
1357                 }
1358                 ret = smb_krb5_kt_free_entry(context, &kt_entry);
1359                 ZERO_STRUCT(kt_entry);
1360                 if (ret) {
1361                         DEBUG(1, (__location__ ": krb5_kt_remove_entry() "
1362                                   "failed (%s)\n", error_message(ret)));
1363                         goto out;
1364                 }
1365         }
1366
1367 out:
1368         talloc_free(tmp_ctx);
1369         if (memcmp(&zero_kt_entry, &kt_entry, sizeof(krb5_keytab_entry))) {
1370                 smb_krb5_kt_free_entry(context, &kt_entry);
1371         }
1372         if (memcmp(&cursor, &zero_csr, sizeof(krb5_kt_cursor)) != 0) {
1373                 krb5_kt_end_seq_get(context, keytab, &cursor);
1374         }
1375         return ret;
1376 }
1377
1378 /**
1379  * @brief Add a keytab entry for the given principal
1380  *
1381  * @param[in]  context       The krb5 context to use.
1382  *
1383  * @param[in]  keytab        The keytab to add the entry to.
1384  *
1385  * @param[in]  kvno          The kvno to use.
1386  *
1387  * @param[in]  princ_s       The principal as a string.
1388  *
1389  * @param[in]  salt_principal The salt principal to salt the password with.
1390  *                            Only needed for keys which support salting.
1391  *                            If no salt is used set no_salt to false and
1392  *                            pass NULL here.
1393  *
1394  * @param[in]  enctype        The encryption type of the keytab entry.
1395  *
1396  * @param[in]  password       The password of the keytab entry.
1397  *
1398  * @param[in]  no_salt        If the password should not be salted. Normally
1399  *                            this is only set to false for encryption types
1400  *                            which do not support salting like RC4.
1401  *
1402  * @param[in]  keep_old_entries Wether to keep or delte old keytab entries.
1403  *
1404  * @retval 0 on Success
1405  *
1406  * @return A corresponding KRB5 error code.
1407  *
1408  * @see smb_krb5_kt_open()
1409  */
1410 krb5_error_code smb_krb5_kt_add_entry(krb5_context context,
1411                                       krb5_keytab keytab,
1412                                       krb5_kvno kvno,
1413                                       const char *princ_s,
1414                                       const char *salt_principal,
1415                                       krb5_enctype enctype,
1416                                       krb5_data *password,
1417                                       bool no_salt,
1418                                       bool keep_old_entries)
1419 {
1420         krb5_error_code ret;
1421         krb5_keytab_entry kt_entry;
1422         krb5_principal princ = NULL;
1423         krb5_keyblock *keyp;
1424
1425         ZERO_STRUCT(kt_entry);
1426
1427         ret = smb_krb5_parse_name(context, princ_s, &princ);
1428         if (ret) {
1429                 DEBUG(1, (__location__ ": smb_krb5_parse_name(%s) "
1430                           "failed (%s)\n", princ_s, error_message(ret)));
1431                 goto out;
1432         }
1433
1434         /* Seek and delete old keytab entries */
1435         ret = smb_krb5_kt_seek_and_delete_old_entries(context,
1436                                                       keytab,
1437                                                       kvno,
1438                                                       enctype,
1439                                                       princ_s,
1440                                                       princ,
1441                                                       false,
1442                                                       keep_old_entries);
1443         if (ret) {
1444                 goto out;
1445         }
1446
1447         /* If we get here, we have deleted all the old entries with kvno's
1448          * not equal to the current kvno-1. */
1449
1450         keyp = KRB5_KT_KEY(&kt_entry);
1451
1452         if (no_salt) {
1453                 KRB5_KEY_DATA(keyp) = (KRB5_KEY_DATA_CAST *)SMB_MALLOC(password->length);
1454                 if (KRB5_KEY_DATA(keyp) == NULL) {
1455                         ret = ENOMEM;
1456                         goto out;
1457                 }
1458                 memcpy(KRB5_KEY_DATA(keyp), password->data, password->length);
1459                 KRB5_KEY_LENGTH(keyp) = password->length;
1460                 KRB5_KEY_TYPE(keyp) = enctype;
1461         } else {
1462                 krb5_principal salt_princ = NULL;
1463
1464                 /* Now add keytab entries for all encryption types */
1465                 ret = smb_krb5_parse_name(context, salt_principal, &salt_princ);
1466                 if (ret) {
1467                         DBG_WARNING("krb5_parse_name(%s) failed (%s)\n",
1468                                     salt_principal, error_message(ret));
1469                         goto out;
1470                 }
1471
1472                 ret = smb_krb5_create_key_from_string(context,
1473                                                       salt_princ,
1474                                                       NULL,
1475                                                       password,
1476                                                       enctype,
1477                                                       keyp);
1478                 krb5_free_principal(context, salt_princ);
1479                 if (ret != 0) {
1480                         goto out;
1481                 }
1482         }
1483
1484         kt_entry.principal = princ;
1485         kt_entry.vno       = kvno;
1486
1487         DEBUG(3, (__location__ ": adding keytab entry for (%s) with "
1488                   "encryption type (%d) and version (%d)\n",
1489                   princ_s, enctype, kt_entry.vno));
1490         ret = krb5_kt_add_entry(context, keytab, &kt_entry);
1491         krb5_free_keyblock_contents(context, keyp);
1492         ZERO_STRUCT(kt_entry);
1493         if (ret) {
1494                 DEBUG(1, (__location__ ": adding entry to keytab "
1495                           "failed (%s)\n", error_message(ret)));
1496                 goto out;
1497         }
1498
1499 out:
1500         if (princ) {
1501                 krb5_free_principal(context, princ);
1502         }
1503
1504         return ret;
1505 }
1506
1507 #if defined(HAVE_KRB5_GET_CREDS_OPT_SET_IMPERSONATE) && \
1508     defined(HAVE_KRB5_GET_CREDS_OPT_ALLOC) && \
1509     defined(HAVE_KRB5_GET_CREDS)
1510 static krb5_error_code smb_krb5_get_credentials_for_user_opt(krb5_context context,
1511                                                              krb5_ccache ccache,
1512                                                              krb5_principal me,
1513                                                              krb5_principal server,
1514                                                              krb5_principal impersonate_princ,
1515                                                              krb5_creds **out_creds)
1516 {
1517         krb5_error_code ret;
1518         krb5_get_creds_opt opt;
1519
1520         ret = krb5_get_creds_opt_alloc(context, &opt);
1521         if (ret) {
1522                 goto done;
1523         }
1524         krb5_get_creds_opt_add_options(context, opt, KRB5_GC_FORWARDABLE);
1525
1526         if (impersonate_princ) {
1527                 ret = krb5_get_creds_opt_set_impersonate(context, opt,
1528                                                          impersonate_princ);
1529                 if (ret) {
1530                         goto done;
1531                 }
1532         }
1533
1534         ret = krb5_get_creds(context, opt, ccache, server, out_creds);
1535         if (ret) {
1536                 goto done;
1537         }
1538
1539  done:
1540         if (opt) {
1541                 krb5_get_creds_opt_free(context, opt);
1542         }
1543         return ret;
1544 }
1545 #endif /* HAVE_KRB5_GET_CREDS_OPT_SET_IMPERSONATE */
1546
1547 #ifdef HAVE_KRB5_GET_CREDENTIALS_FOR_USER
1548
1549 #if !HAVE_DECL_KRB5_GET_CREDENTIALS_FOR_USER
1550 krb5_error_code KRB5_CALLCONV
1551 krb5_get_credentials_for_user(krb5_context context, krb5_flags options,
1552                               krb5_ccache ccache, krb5_creds *in_creds,
1553                               krb5_data *subject_cert,
1554                               krb5_creds **out_creds);
1555 #endif /* !HAVE_DECL_KRB5_GET_CREDENTIALS_FOR_USER */
1556
1557 static krb5_error_code smb_krb5_get_credentials_for_user(krb5_context context,
1558                                                          krb5_ccache ccache,
1559                                                          krb5_principal me,
1560                                                          krb5_principal server,
1561                                                          krb5_principal impersonate_princ,
1562                                                          krb5_creds **out_creds)
1563 {
1564         krb5_error_code ret;
1565         krb5_creds in_creds;
1566
1567         ZERO_STRUCT(in_creds);
1568
1569         if (impersonate_princ) {
1570
1571                 in_creds.server = me;
1572                 in_creds.client = impersonate_princ;
1573
1574                 ret = krb5_get_credentials_for_user(context,
1575                                                     0, /* krb5_flags options */
1576                                                     ccache,
1577                                                     &in_creds,
1578                                                     NULL, /* krb5_data *subject_cert */
1579                                                     out_creds);
1580         } else {
1581                 in_creds.client = me;
1582                 in_creds.server = server;
1583
1584                 ret = krb5_get_credentials(context, 0, ccache,
1585                                            &in_creds, out_creds);
1586         }
1587
1588         return ret;
1589 }
1590 #endif /* HAVE_KRB5_GET_CREDENTIALS_FOR_USER */
1591
1592 /*
1593  * smb_krb5_get_credentials
1594  *
1595  * @brief Get krb5 credentials for a server
1596  *
1597  * @param[in] context           An initialized krb5_context
1598  * @param[in] ccache            An initialized krb5_ccache
1599  * @param[in] me                The krb5_principal of the caller
1600  * @param[in] server            The krb5_principal of the requested service
1601  * @param[in] impersonate_princ The krb5_principal of a user to impersonate as (optional)
1602  * @param[out] out_creds        The returned krb5_creds structure
1603  * @return krb5_error_code
1604  *
1605  */
1606 krb5_error_code smb_krb5_get_credentials(krb5_context context,
1607                                          krb5_ccache ccache,
1608                                          krb5_principal me,
1609                                          krb5_principal server,
1610                                          krb5_principal impersonate_princ,
1611                                          krb5_creds **out_creds)
1612 {
1613         krb5_error_code ret;
1614         krb5_creds *creds = NULL;
1615
1616         if (out_creds != NULL) {
1617                 *out_creds = NULL;
1618         }
1619
1620         if (impersonate_princ) {
1621 #ifdef HAVE_KRB5_GET_CREDS_OPT_SET_IMPERSONATE /* Heimdal */
1622                 ret = smb_krb5_get_credentials_for_user_opt(context, ccache, me, server, impersonate_princ, &creds);
1623 #elif defined(HAVE_KRB5_GET_CREDENTIALS_FOR_USER) /* MIT */
1624                 ret = smb_krb5_get_credentials_for_user(context, ccache, me, server, impersonate_princ, &creds);
1625 #else
1626                 ret = ENOTSUP;
1627 #endif
1628         } else {
1629                 krb5_creds in_creds;
1630
1631                 ZERO_STRUCT(in_creds);
1632
1633                 in_creds.client = me;
1634                 in_creds.server = server;
1635
1636                 ret = krb5_get_credentials(context, 0, ccache,
1637                                            &in_creds, &creds);
1638         }
1639         if (ret) {
1640                 goto done;
1641         }
1642
1643         if (out_creds) {
1644                 *out_creds = creds;
1645         }
1646
1647  done:
1648         if (creds && ret) {
1649                 krb5_free_creds(context, creds);
1650         }
1651
1652         return ret;
1653 }
1654
1655 /**
1656  * @brief Initialize a krb5_keyblock with the given data.
1657  *
1658  * Initialized a new keyblock, allocates the contents fo the key and
1659  * copies the data into the keyblock.
1660  *
1661  * @param[in]  context  The library context
1662  *
1663  * @param[in]  enctype  The encryption type.
1664  *
1665  * @param[in]  data     The date to initialize the keyblock with.
1666  *
1667  * @param[in]  length   The length of the keyblock.
1668  *
1669  * @param[in]  key      Newly allocated keyblock structure.
1670  *
1671  * The key date must be freed using krb5_free_keyblock_contents() when it is
1672  * no longer needed.
1673  *
1674  * @return 0 on success, a Kerberos error code otherwise.
1675  */
1676 krb5_error_code smb_krb5_keyblock_init_contents(krb5_context context,
1677                                                 krb5_enctype enctype,
1678                                                 const void *data,
1679                                                 size_t length,
1680                                                 krb5_keyblock *key)
1681 {
1682 #if defined(HAVE_KRB5_KEYBLOCK_INIT)
1683         return krb5_keyblock_init(context, enctype, data, length, key);
1684 #elif defined(HAVE_KRB5_INIT_KEYBLOCK)
1685         krb5_error_code code;
1686
1687         code = krb5_init_keyblock(context,
1688                                   enctype,
1689                                   length,
1690                                   key);
1691         if (code != 0) {
1692                 return code;
1693         }
1694
1695         if (length != 0) {
1696                 memcpy(KRB5_KEY_DATA(key), data, length);
1697         }
1698
1699         return 0;
1700 #else
1701         memset(key, 0, sizeof(krb5_keyblock));
1702         KRB5_KEY_DATA(key) = SMB_MALLOC(length);
1703         if (NULL == KRB5_KEY_DATA(key)) {
1704                 return ENOMEM;
1705         }
1706         memcpy(KRB5_KEY_DATA(key), data, length);
1707         KRB5_KEY_LENGTH(key) = length;
1708         KRB5_KEY_TYPE(key) = enctype;
1709         return 0;
1710 #endif
1711 }
1712
1713 /*
1714   simulate a kinit, putting the tgt in the given credentials cache.
1715   Orignally by remus@snapserver.com
1716
1717   This version is built to use a keyblock, rather than needing the
1718   original password.
1719
1720   The impersonate_principal is the principal if NULL, or the principal
1721   to impersonate
1722
1723   The target_service defaults to the krbtgt if NULL, but could be
1724    kpasswd/realm or the local service (if we are doing s4u2self)
1725 */
1726 krb5_error_code kerberos_kinit_keyblock_cc(krb5_context ctx, krb5_ccache cc,
1727                                            krb5_principal principal,
1728                                            krb5_keyblock *keyblock,
1729                                            const char *target_service,
1730                                            krb5_get_init_creds_opt *krb_options,
1731                                            time_t *expire_time,
1732                                            time_t *kdc_time)
1733 {
1734         krb5_error_code code = 0;
1735         krb5_creds my_creds;
1736
1737 #if defined(HAVE_KRB5_GET_INIT_CREDS_KEYBLOCK)
1738         code = krb5_get_init_creds_keyblock(ctx, &my_creds, principal,
1739                                             keyblock, 0, target_service,
1740                                             krb_options);
1741 #elif defined(HAVE_KRB5_GET_INIT_CREDS_KEYTAB)
1742 {
1743 #define SMB_CREDS_KEYTAB "MEMORY:tmp_smb_creds_XXXXXX"
1744         char tmp_name[sizeof(SMB_CREDS_KEYTAB)];
1745         krb5_keytab_entry entry;
1746         krb5_keytab keytab;
1747         mode_t mask;
1748
1749         memset(&entry, 0, sizeof(entry));
1750         entry.principal = principal;
1751         *(KRB5_KT_KEY(&entry)) = *keyblock;
1752
1753         memcpy(tmp_name, SMB_CREDS_KEYTAB, sizeof(SMB_CREDS_KEYTAB));
1754         mask = umask(S_IRWXO | S_IRWXG);
1755         mktemp(tmp_name);
1756         umask(mask);
1757         if (tmp_name[0] == 0) {
1758                 return KRB5_KT_BADNAME;
1759         }
1760         code = krb5_kt_resolve(ctx, tmp_name, &keytab);
1761         if (code) {
1762                 return code;
1763         }
1764
1765         code = krb5_kt_add_entry(ctx, keytab, &entry);
1766         if (code) {
1767                 (void)krb5_kt_close(ctx, keytab);
1768                 goto done;
1769         }
1770
1771         code = krb5_get_init_creds_keytab(ctx, &my_creds, principal,
1772                                           keytab, 0, target_service,
1773                                           krb_options);
1774         (void)krb5_kt_close(ctx, keytab);
1775 }
1776 #else
1777 #error krb5_get_init_creds_keyblock not available!
1778 #endif
1779         if (code) {
1780                 return code;
1781         }
1782
1783 #ifndef SAMBA4_USES_HEIMDAL /* MIT */
1784         /*
1785          * We need to store the principal as returned from the KDC to the
1786          * credentials cache. If we don't do that the KRB5 library is not
1787          * able to find the tickets it is looking for
1788          */
1789         principal = my_creds.client;
1790 #endif
1791         code = krb5_cc_initialize(ctx, cc, principal);
1792         if (code) {
1793                 goto done;
1794         }
1795
1796         code = krb5_cc_store_cred(ctx, cc, &my_creds);
1797         if (code) {
1798                 goto done;
1799         }
1800
1801         if (expire_time) {
1802                 *expire_time = (time_t) my_creds.times.endtime;
1803         }
1804
1805         if (kdc_time) {
1806                 *kdc_time = (time_t) my_creds.times.starttime;
1807         }
1808
1809         code = 0;
1810 done:
1811         krb5_free_cred_contents(ctx, &my_creds);
1812         return code;
1813 }
1814
1815 krb5_error_code kerberos_kinit_password_cc(krb5_context ctx, krb5_ccache cc,
1816                                            krb5_principal principal,
1817                                            const char *password,
1818                                            const char *target_service,
1819                                            krb5_get_init_creds_opt *krb_options,
1820                                            time_t *expire_time,
1821                                            time_t *kdc_time)
1822 {
1823         krb5_error_code code = 0;
1824         krb5_creds my_creds;
1825
1826         code = krb5_get_init_creds_password(ctx, &my_creds, principal,
1827                                             password, NULL, NULL, 0,
1828                                             target_service, krb_options);
1829         if (code) {
1830                 return code;
1831         }
1832
1833 #ifndef SAMBA4_USES_HEIMDAL /* MIT */
1834         /*
1835          * We need to store the principal as returned from the KDC to the
1836          * credentials cache. If we don't do that the KRB5 library is not
1837          * able to find the tickets it is looking for
1838          */
1839         principal = my_creds.client;
1840 #endif
1841         code = krb5_cc_initialize(ctx, cc, principal);
1842         if (code) {
1843                 goto done;
1844         }
1845
1846         code = krb5_cc_store_cred(ctx, cc, &my_creds);
1847         if (code) {
1848                 goto done;
1849         }
1850
1851         if (expire_time) {
1852                 *expire_time = (time_t) my_creds.times.endtime;
1853         }
1854
1855         if (kdc_time) {
1856                 *kdc_time = (time_t) my_creds.times.starttime;
1857         }
1858
1859         code = 0;
1860 done:
1861         krb5_free_cred_contents(ctx, &my_creds);
1862         return code;
1863 }
1864
1865 #ifdef SAMBA4_USES_HEIMDAL
1866 /*
1867   simulate a kinit, putting the tgt in the given credentials cache.
1868   Orignally by remus@snapserver.com
1869
1870   The impersonate_principal is the principal
1871
1872   The self_service, should be the local service (for S4U2Self if
1873   impersonate_principal is given).
1874
1875   The target_service defaults to the krbtgt if NULL, but could be
1876   kpasswd/realm or a remote service (for S4U2Proxy)
1877
1878 */
1879 krb5_error_code kerberos_kinit_s4u2_cc(krb5_context ctx,
1880                                         krb5_ccache store_cc,
1881                                         krb5_principal init_principal,
1882                                         const char *init_password,
1883                                         krb5_principal impersonate_principal,
1884                                         const char *self_service,
1885                                         const char *target_service,
1886                                         krb5_get_init_creds_opt *krb_options,
1887                                         time_t *expire_time,
1888                                         time_t *kdc_time)
1889 {
1890         krb5_error_code code = 0;
1891         krb5_get_creds_opt options;
1892         krb5_principal store_principal;
1893         krb5_creds store_creds;
1894         krb5_creds *s4u2self_creds;
1895         Ticket s4u2self_ticket;
1896         size_t s4u2self_ticketlen;
1897         krb5_creds *s4u2proxy_creds;
1898         krb5_principal self_princ;
1899         bool s4u2proxy;
1900         krb5_principal target_princ;
1901         krb5_ccache tmp_cc;
1902         const char *self_realm;
1903         krb5_principal blacklist_principal = NULL;
1904         krb5_principal whitelist_principal = NULL;
1905
1906         code = krb5_get_init_creds_password(ctx, &store_creds,
1907                                             init_principal,
1908                                             init_password,
1909                                             NULL, NULL,
1910                                             0,
1911                                             NULL,
1912                                             krb_options);
1913         if (code != 0) {
1914                 return code;
1915         }
1916
1917         store_principal = init_principal;
1918
1919         /*
1920          * We are trying S4U2Self now:
1921          *
1922          * As we do not want to expose our TGT in the
1923          * krb5_ccache, which is also holds the impersonated creds.
1924          *
1925          * Some low level krb5/gssapi function might use the TGT
1926          * identity and let the client act as our machine account.
1927          *
1928          * We need to avoid that and use a temporary krb5_ccache
1929          * in order to pass our TGT to the krb5_get_creds() function.
1930          */
1931         code = krb5_cc_new_unique(ctx, NULL, NULL, &tmp_cc);
1932         if (code != 0) {
1933                 krb5_free_cred_contents(ctx, &store_creds);
1934                 return code;
1935         }
1936
1937         code = krb5_cc_initialize(ctx, tmp_cc, store_creds.client);
1938         if (code != 0) {
1939                 krb5_cc_destroy(ctx, tmp_cc);
1940                 krb5_free_cred_contents(ctx, &store_creds);
1941                 return code;
1942         }
1943
1944         code = krb5_cc_store_cred(ctx, tmp_cc, &store_creds);
1945         if (code != 0) {
1946                 krb5_free_cred_contents(ctx, &store_creds);
1947                 krb5_cc_destroy(ctx, tmp_cc);
1948                 return code;
1949         }
1950
1951         /*
1952          * we need to remember the client principal of our
1953          * TGT and make sure the KDC does not return this
1954          * in the impersonated tickets. This can happen
1955          * if the KDC does not support S4U2Self and S4U2Proxy.
1956          */
1957         blacklist_principal = store_creds.client;
1958         store_creds.client = NULL;
1959         krb5_free_cred_contents(ctx, &store_creds);
1960
1961         /*
1962          * Check if we also need S4U2Proxy or if S4U2Self is
1963          * enough in order to get a ticket for the target.
1964          */
1965         if (target_service == NULL) {
1966                 s4u2proxy = false;
1967         } else if (strcmp(target_service, self_service) == 0) {
1968                 s4u2proxy = false;
1969         } else {
1970                 s4u2proxy = true;
1971         }
1972
1973         /*
1974          * For S4U2Self we need our own service principal,
1975          * which belongs to our own realm (available on
1976          * our client principal).
1977          */
1978         self_realm = krb5_principal_get_realm(ctx, init_principal);
1979
1980         code = krb5_parse_name(ctx, self_service, &self_princ);
1981         if (code != 0) {
1982                 krb5_free_principal(ctx, blacklist_principal);
1983                 krb5_cc_destroy(ctx, tmp_cc);
1984                 return code;
1985         }
1986
1987         code = krb5_principal_set_realm(ctx, self_princ, self_realm);
1988         if (code != 0) {
1989                 krb5_free_principal(ctx, blacklist_principal);
1990                 krb5_free_principal(ctx, self_princ);
1991                 krb5_cc_destroy(ctx, tmp_cc);
1992                 return code;
1993         }
1994
1995         code = krb5_get_creds_opt_alloc(ctx, &options);
1996         if (code != 0) {
1997                 krb5_free_principal(ctx, blacklist_principal);
1998                 krb5_free_principal(ctx, self_princ);
1999                 krb5_cc_destroy(ctx, tmp_cc);
2000                 return code;
2001         }
2002
2003         if (s4u2proxy) {
2004                 /*
2005                  * If we want S4U2Proxy, we need the forwardable flag
2006                  * on the S4U2Self ticket.
2007                  */
2008                 krb5_get_creds_opt_set_options(ctx, options, KRB5_GC_FORWARDABLE);
2009         }
2010
2011         code = krb5_get_creds_opt_set_impersonate(ctx, options,
2012                                                   impersonate_principal);
2013         if (code != 0) {
2014                 krb5_get_creds_opt_free(ctx, options);
2015                 krb5_free_principal(ctx, blacklist_principal);
2016                 krb5_free_principal(ctx, self_princ);
2017                 krb5_cc_destroy(ctx, tmp_cc);
2018                 return code;
2019         }
2020
2021         code = krb5_get_creds(ctx, options, tmp_cc,
2022                               self_princ, &s4u2self_creds);
2023         krb5_get_creds_opt_free(ctx, options);
2024         krb5_free_principal(ctx, self_princ);
2025         if (code != 0) {
2026                 krb5_free_principal(ctx, blacklist_principal);
2027                 krb5_cc_destroy(ctx, tmp_cc);
2028                 return code;
2029         }
2030
2031         if (!s4u2proxy) {
2032                 krb5_cc_destroy(ctx, tmp_cc);
2033
2034                 /*
2035                  * Now make sure we store the impersonated principal
2036                  * and creds instead of the TGT related stuff
2037                  * in the krb5_ccache of the caller.
2038                  */
2039                 code = krb5_copy_creds_contents(ctx, s4u2self_creds,
2040                                                 &store_creds);
2041                 krb5_free_creds(ctx, s4u2self_creds);
2042                 if (code != 0) {
2043                         return code;
2044                 }
2045
2046                 /*
2047                  * It's important to store the principal the KDC
2048                  * returned, as otherwise the caller would not find
2049                  * the S4U2Self ticket in the krb5_ccache lookup.
2050                  */
2051                 store_principal = store_creds.client;
2052                 goto store;
2053         }
2054
2055         /*
2056          * We are trying S4U2Proxy:
2057          *
2058          * We need the ticket from the S4U2Self step
2059          * and our TGT in order to get the delegated ticket.
2060          */
2061         code = decode_Ticket((const uint8_t *)s4u2self_creds->ticket.data,
2062                              s4u2self_creds->ticket.length,
2063                              &s4u2self_ticket,
2064                              &s4u2self_ticketlen);
2065         if (code != 0) {
2066                 krb5_free_creds(ctx, s4u2self_creds);
2067                 krb5_free_principal(ctx, blacklist_principal);
2068                 krb5_cc_destroy(ctx, tmp_cc);
2069                 return code;
2070         }
2071
2072         /*
2073          * we need to remember the client principal of the
2074          * S4U2Self stage and as it needs to match the one we
2075          * will get for the S4U2Proxy stage. We need this
2076          * in order to detect KDCs which does not support S4U2Proxy.
2077          */
2078         whitelist_principal = s4u2self_creds->client;
2079         s4u2self_creds->client = NULL;
2080         krb5_free_creds(ctx, s4u2self_creds);
2081
2082         /*
2083          * For S4U2Proxy we also got a target service principal,
2084          * which also belongs to our own realm (available on
2085          * our client principal).
2086          */
2087         code = krb5_parse_name(ctx, target_service, &target_princ);
2088         if (code != 0) {
2089                 free_Ticket(&s4u2self_ticket);
2090                 krb5_free_principal(ctx, whitelist_principal);
2091                 krb5_free_principal(ctx, blacklist_principal);
2092                 krb5_cc_destroy(ctx, tmp_cc);
2093                 return code;
2094         }
2095
2096         code = krb5_principal_set_realm(ctx, target_princ, self_realm);
2097         if (code != 0) {
2098                 free_Ticket(&s4u2self_ticket);
2099                 krb5_free_principal(ctx, target_princ);
2100                 krb5_free_principal(ctx, whitelist_principal);
2101                 krb5_free_principal(ctx, blacklist_principal);
2102                 krb5_cc_destroy(ctx, tmp_cc);
2103                 return code;
2104         }
2105
2106         code = krb5_get_creds_opt_alloc(ctx, &options);
2107         if (code != 0) {
2108                 free_Ticket(&s4u2self_ticket);
2109                 krb5_free_principal(ctx, target_princ);
2110                 krb5_free_principal(ctx, whitelist_principal);
2111                 krb5_free_principal(ctx, blacklist_principal);
2112                 krb5_cc_destroy(ctx, tmp_cc);
2113                 return code;
2114         }
2115
2116         krb5_get_creds_opt_set_options(ctx, options, KRB5_GC_FORWARDABLE);
2117         krb5_get_creds_opt_set_options(ctx, options, KRB5_GC_CONSTRAINED_DELEGATION);
2118
2119         code = krb5_get_creds_opt_set_ticket(ctx, options, &s4u2self_ticket);
2120         free_Ticket(&s4u2self_ticket);
2121         if (code != 0) {
2122                 krb5_get_creds_opt_free(ctx, options);
2123                 krb5_free_principal(ctx, target_princ);
2124                 krb5_free_principal(ctx, whitelist_principal);
2125                 krb5_free_principal(ctx, blacklist_principal);
2126                 krb5_cc_destroy(ctx, tmp_cc);
2127                 return code;
2128         }
2129
2130         code = krb5_get_creds(ctx, options, tmp_cc,
2131                               target_princ, &s4u2proxy_creds);
2132         krb5_get_creds_opt_free(ctx, options);
2133         krb5_free_principal(ctx, target_princ);
2134         krb5_cc_destroy(ctx, tmp_cc);
2135         if (code != 0) {
2136                 krb5_free_principal(ctx, whitelist_principal);
2137                 krb5_free_principal(ctx, blacklist_principal);
2138                 return code;
2139         }
2140
2141         /*
2142          * Now make sure we store the impersonated principal
2143          * and creds instead of the TGT related stuff
2144          * in the krb5_ccache of the caller.
2145          */
2146         code = krb5_copy_creds_contents(ctx, s4u2proxy_creds,
2147                                         &store_creds);
2148         krb5_free_creds(ctx, s4u2proxy_creds);
2149         if (code != 0) {
2150                 krb5_free_principal(ctx, whitelist_principal);
2151                 krb5_free_principal(ctx, blacklist_principal);
2152                 return code;
2153         }
2154
2155         /*
2156          * It's important to store the principal the KDC
2157          * returned, as otherwise the caller would not find
2158          * the S4U2Self ticket in the krb5_ccache lookup.
2159          */
2160         store_principal = store_creds.client;
2161
2162  store:
2163         if (blacklist_principal &&
2164             krb5_principal_compare(ctx, store_creds.client, blacklist_principal)) {
2165                 char *sp = NULL;
2166                 char *ip = NULL;
2167
2168                 code = krb5_unparse_name(ctx, blacklist_principal, &sp);
2169                 if (code != 0) {
2170                         sp = NULL;
2171                 }
2172                 code = krb5_unparse_name(ctx, impersonate_principal, &ip);
2173                 if (code != 0) {
2174                         ip = NULL;
2175                 }
2176                 DEBUG(1, ("kerberos_kinit_password_cc: "
2177                           "KDC returned self principal[%s] while impersonating [%s]\n",
2178                           sp?sp:"<no memory>",
2179                           ip?ip:"<no memory>"));
2180
2181                 SAFE_FREE(sp);
2182                 SAFE_FREE(ip);
2183
2184                 krb5_free_principal(ctx, whitelist_principal);
2185                 krb5_free_principal(ctx, blacklist_principal);
2186                 krb5_free_cred_contents(ctx, &store_creds);
2187                 return KRB5_FWD_BAD_PRINCIPAL;
2188         }
2189         if (blacklist_principal) {
2190                 krb5_free_principal(ctx, blacklist_principal);
2191         }
2192
2193         if (whitelist_principal &&
2194             !krb5_principal_compare(ctx, store_creds.client, whitelist_principal)) {
2195                 char *sp = NULL;
2196                 char *ep = NULL;
2197
2198                 code = krb5_unparse_name(ctx, store_creds.client, &sp);
2199                 if (code != 0) {
2200                         sp = NULL;
2201                 }
2202                 code = krb5_unparse_name(ctx, whitelist_principal, &ep);
2203                 if (code != 0) {
2204                         ep = NULL;
2205                 }
2206                 DEBUG(1, ("kerberos_kinit_password_cc: "
2207                           "KDC returned wrong principal[%s] we expected [%s]\n",
2208                           sp?sp:"<no memory>",
2209                           ep?ep:"<no memory>"));
2210
2211                 SAFE_FREE(sp);
2212                 SAFE_FREE(ep);
2213
2214                 krb5_free_principal(ctx, whitelist_principal);
2215                 krb5_free_cred_contents(ctx, &store_creds);
2216                 return KRB5_FWD_BAD_PRINCIPAL;
2217         }
2218         if (whitelist_principal) {
2219                 krb5_free_principal(ctx, whitelist_principal);
2220         }
2221
2222         code = krb5_cc_initialize(ctx, store_cc, store_principal);
2223         if (code != 0) {
2224                 krb5_free_cred_contents(ctx, &store_creds);
2225                 return code;
2226         }
2227
2228         code = krb5_cc_store_cred(ctx, store_cc, &store_creds);
2229         if (code != 0) {
2230                 krb5_free_cred_contents(ctx, &store_creds);
2231                 return code;
2232         }
2233
2234         if (expire_time) {
2235                 *expire_time = (time_t) store_creds.times.endtime;
2236         }
2237
2238         if (kdc_time) {
2239                 *kdc_time = (time_t) store_creds.times.starttime;
2240         }
2241
2242         krb5_free_cred_contents(ctx, &store_creds);
2243
2244         return 0;
2245 }
2246 #endif
2247
2248 #if !defined(HAVE_KRB5_MAKE_PRINCIPAL) && defined(HAVE_KRB5_BUILD_PRINCIPAL_ALLOC_VA)
2249 krb5_error_code smb_krb5_make_principal(krb5_context context,
2250                                         krb5_principal *principal,
2251                                         const char *_realm, ...)
2252 {
2253         krb5_error_code code;
2254         bool free_realm;
2255         char *realm;
2256         va_list ap;
2257
2258         if (_realm) {
2259                 realm = discard_const_p(char, _realm);
2260                 free_realm = false;
2261         } else {
2262                 code = krb5_get_default_realm(context, &realm);
2263                 if (code) {
2264                         return code;
2265                 }
2266                 free_realm = true;
2267         }
2268
2269         va_start(ap, _realm);
2270         code = krb5_build_principal_alloc_va(context, principal,
2271                                              strlen(realm), realm,
2272                                              ap);
2273         va_end(ap);
2274
2275         if (free_realm) {
2276                 krb5_free_default_realm(context, realm);
2277         }
2278
2279         return code;
2280 }
2281 #endif
2282
2283 #if !defined(HAVE_KRB5_CC_GET_LIFETIME) && defined(HAVE_KRB5_CC_RETRIEVE_CRED)
2284 /**
2285  * @brief Get the lifetime of the initial ticket in the cache.
2286  *
2287  * @param[in]  context  The kerberos context.
2288  *
2289  * @param[in]  id       The credential cache to get the ticket lifetime.
2290  *
2291  * @param[out] t        A pointer to a time value to store the lifetime.
2292  *
2293  * @return              0 on success, a krb5_error_code on error.
2294  */
2295 krb5_error_code smb_krb5_cc_get_lifetime(krb5_context context,
2296                                          krb5_ccache id,
2297                                          time_t *t)
2298 {
2299         krb5_cc_cursor cursor;
2300         krb5_error_code kerr;
2301         krb5_creds cred;
2302         krb5_timestamp now;
2303
2304         *t = 0;
2305
2306         kerr = krb5_timeofday(context, &now);
2307         if (kerr) {
2308                 return kerr;
2309         }
2310
2311         kerr = krb5_cc_start_seq_get(context, id, &cursor);
2312         if (kerr) {
2313                 return kerr;
2314         }
2315
2316         while ((kerr = krb5_cc_next_cred(context, id, &cursor, &cred)) == 0) {
2317 #ifndef HAVE_FLAGS_IN_KRB5_CREDS
2318                 if (cred.ticket_flags & TKT_FLG_INITIAL) {
2319 #else
2320                 if (cred.flags.b.initial) {
2321 #endif
2322                         if (now < cred.times.endtime) {
2323                                 *t = (time_t) (cred.times.endtime - now);
2324                         }
2325                         krb5_free_cred_contents(context, &cred);
2326                         break;
2327                 }
2328                 krb5_free_cred_contents(context, &cred);
2329         }
2330
2331         krb5_cc_end_seq_get(context, id, &cursor);
2332
2333         return kerr;
2334 }
2335 #endif /* HAVE_KRB5_CC_GET_LIFETIME */
2336
2337 #if !defined(HAVE_KRB5_FREE_CHECKSUM_CONTENTS) && defined(HAVE_FREE_CHECKSUM)
2338 void smb_krb5_free_checksum_contents(krb5_context ctx, krb5_checksum *cksum)
2339 {
2340         free_Checksum(cksum);
2341 }
2342 #endif
2343
2344 krb5_error_code smb_krb5_make_pac_checksum(TALLOC_CTX *mem_ctx,
2345                                            DATA_BLOB *pac_data,
2346                                            krb5_context context,
2347                                            const krb5_keyblock *keyblock,
2348                                            uint32_t *sig_type,
2349                                            DATA_BLOB *sig_blob)
2350 {
2351         krb5_error_code ret;
2352         krb5_checksum cksum;
2353 #if defined(HAVE_KRB5_CRYPTO_INIT) && defined(HAVE_KRB5_CREATE_CHECKSUM)
2354         krb5_crypto crypto;
2355
2356
2357         ret = krb5_crypto_init(context,
2358                                keyblock,
2359                                0,
2360                                &crypto);
2361         if (ret) {
2362                 DEBUG(0,("krb5_crypto_init() failed: %s\n",
2363                           smb_get_krb5_error_message(context, ret, mem_ctx)));
2364                 return ret;
2365         }
2366         ret = krb5_create_checksum(context,
2367                                    crypto,
2368                                    KRB5_KU_OTHER_CKSUM,
2369                                    0,
2370                                    pac_data->data,
2371                                    pac_data->length,
2372                                    &cksum);
2373         if (ret) {
2374                 DEBUG(2, ("PAC Verification failed: %s\n",
2375                           smb_get_krb5_error_message(context, ret, mem_ctx)));
2376         }
2377
2378         krb5_crypto_destroy(context, crypto);
2379
2380         if (ret) {
2381                 return ret;
2382         }
2383
2384         *sig_type = cksum.cksumtype;
2385         *sig_blob = data_blob_talloc(mem_ctx,
2386                                         cksum.checksum.data,
2387                                         cksum.checksum.length);
2388 #elif defined(HAVE_KRB5_C_MAKE_CHECKSUM)
2389         krb5_data input;
2390
2391         input.data = (char *)pac_data->data;
2392         input.length = pac_data->length;
2393
2394         ret = krb5_c_make_checksum(context,
2395                                    0,
2396                                    keyblock,
2397                                    KRB5_KEYUSAGE_APP_DATA_CKSUM,
2398                                    &input,
2399                                    &cksum);
2400         if (ret) {
2401                 DEBUG(2, ("PAC Verification failed: %s\n",
2402                           smb_get_krb5_error_message(context, ret, mem_ctx)));
2403                 return ret;
2404         }
2405
2406         *sig_type = cksum.checksum_type;
2407         *sig_blob = data_blob_talloc(mem_ctx,
2408                                         cksum.contents,
2409                                         cksum.length);
2410
2411 #else
2412 #error krb5_create_checksum or krb5_c_make_checksum not available
2413 #endif /* HAVE_KRB5_C_MAKE_CHECKSUM */
2414         smb_krb5_free_checksum_contents(context, &cksum);
2415
2416         return 0;
2417 }
2418
2419
2420 /*
2421  * smb_krb5_principal_get_realm
2422  *
2423  * @brief Get realm of a principal
2424  *
2425  * @param[in] context           The krb5_context
2426  * @param[in] principal         The principal
2427  * @return pointer to the realm
2428  *
2429  * Caller must free if the return value is not NULL.
2430  *
2431  */
2432
2433 char *smb_krb5_principal_get_realm(krb5_context context,
2434                                    krb5_const_principal principal)
2435 {
2436 #ifdef HAVE_KRB5_PRINCIPAL_GET_REALM /* Heimdal */
2437         return strdup(discard_const_p(char, krb5_principal_get_realm(context, principal)));
2438 #elif defined(krb5_princ_realm) /* MIT */
2439         krb5_data *realm;
2440         realm = discard_const_p(krb5_data,
2441                                 krb5_princ_realm(context, principal));
2442         return strndup(realm->data, realm->length);
2443 #else
2444 #error UNKNOWN_GET_PRINC_REALM_FUNCTIONS
2445 #endif
2446 }
2447
2448 /*
2449  * smb_krb5_principal_set_realm
2450  *
2451  * @brief Get realm of a principal
2452  *
2453  * @param[in] context           The krb5_context
2454  * @param[in] principal         The principal
2455  * @param[in] realm             The realm
2456  * @return                      0 on success, a krb5_error_code on error.
2457  *
2458  */
2459
2460 krb5_error_code smb_krb5_principal_set_realm(krb5_context context,
2461                                              krb5_principal principal,
2462                                              const char *realm)
2463 {
2464 #ifdef HAVE_KRB5_PRINCIPAL_SET_REALM /* Heimdal */
2465         return krb5_principal_set_realm(context, principal, realm);
2466 #elif defined(krb5_princ_realm) && defined(krb5_princ_set_realm) /* MIT */
2467         krb5_error_code ret;
2468         krb5_data data;
2469         krb5_data *old_data;
2470
2471         old_data = krb5_princ_realm(context, principal);
2472
2473         ret = smb_krb5_copy_data_contents(&data,
2474                                           realm,
2475                                           strlen(realm));
2476         if (ret) {
2477                 return ret;
2478         }
2479
2480         /* free realm before setting */
2481         free(old_data->data);
2482
2483         krb5_princ_set_realm(context, principal, &data);
2484
2485         return ret;
2486 #else
2487 #error UNKNOWN_PRINC_SET_REALM_FUNCTION
2488 #endif
2489 }
2490
2491
2492 /************************************************************************
2493  Routine to get the default realm from the kerberos credentials cache.
2494  Caller must free if the return value is not NULL.
2495 ************************************************************************/
2496
2497 static char *smb_krb5_get_default_realm_from_ccache(TALLOC_CTX *mem_ctx)
2498 {
2499         char *realm = NULL;
2500         krb5_context ctx = NULL;
2501         krb5_ccache cc = NULL;
2502         krb5_principal princ = NULL;
2503
2504         initialize_krb5_error_table();
2505         if (krb5_init_context(&ctx)) {
2506                 return NULL;
2507         }
2508
2509         DEBUG(5,("kerberos_get_default_realm_from_ccache: "
2510                 "Trying to read krb5 cache: %s\n",
2511                 krb5_cc_default_name(ctx)));
2512         if (krb5_cc_default(ctx, &cc)) {
2513                 DEBUG(5,("kerberos_get_default_realm_from_ccache: "
2514                         "failed to read default cache\n"));
2515                 goto out;
2516         }
2517         if (krb5_cc_get_principal(ctx, cc, &princ)) {
2518                 DEBUG(5,("kerberos_get_default_realm_from_ccache: "
2519                         "failed to get default principal\n"));
2520                 goto out;
2521         }
2522
2523 #if defined(HAVE_KRB5_PRINCIPAL_GET_REALM)
2524         realm = talloc_strdup(mem_ctx, krb5_principal_get_realm(ctx, princ));
2525 #elif defined(HAVE_KRB5_PRINC_REALM)
2526         {
2527                 krb5_data *realm_data = krb5_princ_realm(ctx, princ);
2528                 realm = talloc_strndup(mem_ctx, realm_data->data, realm_data->length);
2529         }
2530 #endif
2531
2532   out:
2533
2534         if (ctx) {
2535                 if (princ) {
2536                         krb5_free_principal(ctx, princ);
2537                 }
2538                 if (cc) {
2539                         krb5_cc_close(ctx, cc);
2540                 }
2541                 krb5_free_context(ctx);
2542         }
2543
2544         return realm;
2545 }
2546
2547 /************************************************************************
2548  Routine to get the realm from a given DNS name.
2549 ************************************************************************/
2550
2551 static char *smb_krb5_get_realm_from_hostname(TALLOC_CTX *mem_ctx,
2552                                                 const char *hostname)
2553 {
2554 #if defined(HAVE_KRB5_REALM_TYPE)
2555         /* Heimdal. */
2556         krb5_realm *realm_list = NULL;
2557 #else
2558         /* MIT */
2559         char **realm_list = NULL;
2560 #endif
2561         char *realm = NULL;
2562         krb5_error_code kerr;
2563         krb5_context ctx = NULL;
2564
2565         initialize_krb5_error_table();
2566         if (krb5_init_context(&ctx)) {
2567                 return NULL;
2568         }
2569
2570         kerr = krb5_get_host_realm(ctx, hostname, &realm_list);
2571         if (kerr != 0) {
2572                 DEBUG(3,("kerberos_get_realm_from_hostname %s: "
2573                         "failed %s\n",
2574                         hostname ? hostname : "(NULL)",
2575                         error_message(kerr) ));
2576                 goto out;
2577         }
2578
2579         if (realm_list && realm_list[0]) {
2580                 realm = talloc_strdup(mem_ctx, realm_list[0]);
2581         }
2582
2583   out:
2584
2585         if (ctx) {
2586                 if (realm_list) {
2587                         krb5_free_host_realm(ctx, realm_list);
2588                         realm_list = NULL;
2589                 }
2590                 krb5_free_context(ctx);
2591                 ctx = NULL;
2592         }
2593         return realm;
2594 }
2595
2596 char *kerberos_get_principal_from_service_hostname(TALLOC_CTX *mem_ctx,
2597                                                    const char *service,
2598                                                    const char *remote_name,
2599                                                    const char *default_realm)
2600 {
2601         char *realm = NULL;
2602         char *host = NULL;
2603         char *principal;
2604         host = strchr_m(remote_name, '.');
2605         if (host) {
2606                 /* DNS name. */
2607                 realm = smb_krb5_get_realm_from_hostname(talloc_tos(),
2608                                                          remote_name);
2609         } else {
2610                 /* NetBIOS name - use our realm. */
2611                 realm = smb_krb5_get_default_realm_from_ccache(talloc_tos());
2612         }
2613
2614         if (realm == NULL || *realm == '\0') {
2615                 realm = talloc_strdup(talloc_tos(), default_realm);
2616                 if (!realm) {
2617                         return NULL;
2618                 }
2619                 DEBUG(3,("kerberos_get_principal_from_service_hostname: "
2620                          "cannot get realm from, "
2621                          "desthost %s or default ccache. Using default "
2622                          "smb.conf realm %s\n",
2623                          remote_name,
2624                          realm));
2625         }
2626
2627         principal = talloc_asprintf(mem_ctx,
2628                                     "%s/%s@%s",
2629                                     service, remote_name,
2630                                     realm);
2631         TALLOC_FREE(realm);
2632         return principal;
2633 }
2634
2635 char *smb_get_krb5_error_message(krb5_context context,
2636                                  krb5_error_code code,
2637                                  TALLOC_CTX *mem_ctx)
2638 {
2639         char *ret;
2640
2641 #if defined(HAVE_KRB5_GET_ERROR_MESSAGE) && defined(HAVE_KRB5_FREE_ERROR_MESSAGE)
2642         const char *context_error = krb5_get_error_message(context, code);
2643         if (context_error) {
2644                 ret = talloc_asprintf(mem_ctx, "%s: %s",
2645                                         error_message(code), context_error);
2646                 krb5_free_error_message(context, context_error);
2647                 return ret;
2648         }
2649 #endif
2650         ret = talloc_strdup(mem_ctx, error_message(code));
2651         return ret;
2652 }
2653
2654
2655 /**
2656 * @brief Return the kerberos library setting for "libdefaults:allow_weak_crypto"
2657 *
2658 * @param context        The krb5_context
2659 *
2660 * @return krb5_boolean
2661 *
2662 * Function returns true if weak crypto is allowd, false if not
2663 */
2664
2665 krb5_boolean smb_krb5_get_allowed_weak_crypto(krb5_context context)
2666 #if defined(HAVE_KRB5_CONFIG_GET_BOOL_DEFAULT)
2667 {
2668         return krb5_config_get_bool_default(context,
2669                                             NULL,
2670                                             FALSE,
2671                                             "libdefaults",
2672                                             "allow_weak_crypto",
2673                                             NULL);
2674 }
2675 #elif defined(HAVE_PROFILE_H) && defined(HAVE_KRB5_GET_PROFILE)
2676 {
2677 #include <profile.h>
2678         krb5_error_code ret;
2679         krb5_boolean ret_default = false;
2680         profile_t profile;
2681         int ret_profile;
2682
2683         ret = krb5_get_profile(context,
2684                                &profile);
2685         if (ret) {
2686                 return ret_default;
2687         }
2688
2689         ret = profile_get_boolean(profile,
2690                                   "libdefaults",
2691                                   "allow_weak_crypto",
2692                                   NULL, /* subsubname */
2693                                   ret_default, /* def_val */
2694                                   &ret_profile /* *ret_default */);
2695         if (ret) {
2696                 return ret_default;
2697         }
2698
2699         profile_release(profile);
2700
2701         return ret_profile;
2702 }
2703 #else
2704 #error UNKNOWN_KRB5_CONFIG_ROUTINES
2705 #endif
2706
2707 /**
2708 * @brief Return the type of a krb5_principal
2709 *
2710 * @param context        The krb5_context
2711 * @param principal      The const krb5_principal
2712 *
2713 * @return integer type of the principal
2714 */
2715 int smb_krb5_principal_get_type(krb5_context context,
2716                                 krb5_const_principal principal)
2717 {
2718 #ifdef HAVE_KRB5_PRINCIPAL_GET_TYPE /* Heimdal */
2719         return krb5_principal_get_type(context, principal);
2720 #elif defined(krb5_princ_type) /* MIT */
2721         return krb5_princ_type(context, principal);
2722 #else
2723 #error  UNKNOWN_PRINC_GET_TYPE_FUNCTION
2724 #endif
2725 }
2726
2727 /**
2728 * @brief Set the type of a krb5_principal
2729 *
2730 * @param context        The krb5_context
2731 * @param principal      The const krb5_principal
2732 * @param type           The principal type
2733 *
2734 */
2735 void smb_krb5_principal_set_type(krb5_context context,
2736                                  krb5_principal principal,
2737                                  int type)
2738 {
2739 #ifdef HAVE_KRB5_PRINCIPAL_SET_TYPE /* Heimdal */
2740         krb5_principal_set_type(context, principal, type);
2741 #elif defined(krb5_princ_type) /* MIT */
2742         krb5_princ_type(context, principal) = type;
2743 #else
2744 #error  UNKNOWN_PRINC_SET_TYPE_FUNCTION
2745 #endif
2746 }
2747
2748 /**
2749 * @brief Generate a krb5 warning, forwarding to com_err
2750 *
2751 * @param context        The krb5_context
2752 * @param fmt            The message format
2753 * @param ...            The message arguments
2754 *
2755 * @return
2756 */
2757 #if !defined(HAVE_KRB5_WARNX)
2758 krb5_error_code krb5_warnx(krb5_context context, const char *fmt, ...)
2759 {
2760         va_list args;
2761
2762         va_start(args, fmt);
2763         com_err_va("kdb_samba", errno, fmt, args);
2764         va_end(args);
2765
2766         return 0;
2767 }
2768 #endif
2769
2770 krb5_error_code smb_krb5_cc_copy_creds(krb5_context context,
2771                                        krb5_ccache incc, krb5_ccache outcc)
2772 {
2773 #ifdef HAVE_KRB5_CC_COPY_CACHE /* Heimdal */
2774         return krb5_cc_copy_cache(context, incc, outcc);
2775 #elif defined(HAVE_KRB5_CC_COPY_CREDS)
2776         return krb5_cc_copy_creds(context, incc, outcc);
2777 #else
2778 #error UNKNOWN_KRB5_CC_COPY_CACHE_OR_CREDS_FUNCTION
2779 #endif
2780 }
2781
2782 /**********************************************************
2783  * ADS KRB5 CALLS
2784  **********************************************************/
2785
2786 static bool ads_cleanup_expired_creds(krb5_context context,
2787                                       krb5_ccache  ccache,
2788                                       krb5_creds  *credsp)
2789 {
2790         krb5_error_code retval;
2791         const char *cc_type = krb5_cc_get_type(context, ccache);
2792
2793         DEBUG(3, ("ads_cleanup_expired_creds: Ticket in ccache[%s:%s] expiration %s\n",
2794                   cc_type, krb5_cc_get_name(context, ccache),
2795                   http_timestring(talloc_tos(), credsp->times.endtime)));
2796
2797         /* we will probably need new tickets if the current ones
2798            will expire within 10 seconds.
2799         */
2800         if (credsp->times.endtime >= (time(NULL) + 10))
2801                 return false;
2802
2803         /* heimdal won't remove creds from a file ccache, and
2804            perhaps we shouldn't anyway, since internally we
2805            use memory ccaches, and a FILE one probably means that
2806            we're using creds obtained outside of our exectuable
2807         */
2808         if (strequal(cc_type, "FILE")) {
2809                 DEBUG(5, ("ads_cleanup_expired_creds: We do not remove creds from a %s ccache\n", cc_type));
2810                 return false;
2811         }
2812
2813         retval = krb5_cc_remove_cred(context, ccache, 0, credsp);
2814         if (retval) {
2815                 DEBUG(1, ("ads_cleanup_expired_creds: krb5_cc_remove_cred failed, err %s\n",
2816                           error_message(retval)));
2817                 /* If we have an error in this, we want to display it,
2818                    but continue as though we deleted it */
2819         }
2820         return true;
2821 }
2822
2823 /* Allocate and setup the auth context into the state we need. */
2824
2825 static krb5_error_code ads_setup_auth_context(krb5_context context,
2826                                               krb5_auth_context *auth_context)
2827 {
2828         krb5_error_code retval;
2829
2830         retval = krb5_auth_con_init(context, auth_context );
2831         if (retval) {
2832                 DEBUG(1,("krb5_auth_con_init failed (%s)\n",
2833                         error_message(retval)));
2834                 return retval;
2835         }
2836
2837         /* Ensure this is an addressless ticket. */
2838         retval = krb5_auth_con_setaddrs(context, *auth_context, NULL, NULL);
2839         if (retval) {
2840                 DEBUG(1,("krb5_auth_con_setaddrs failed (%s)\n",
2841                         error_message(retval)));
2842         }
2843
2844         return retval;
2845 }
2846
2847 #if defined(TKT_FLG_OK_AS_DELEGATE ) && defined(HAVE_KRB5_AUTH_CON_SETUSERUSERKEY) && defined(KRB5_AUTH_CONTEXT_USE_SUBKEY) && defined(HAVE_KRB5_AUTH_CON_SET_REQ_CKSUMTYPE)
2848 static krb5_error_code ads_create_gss_checksum(krb5_data *in_data, /* [inout] */
2849                                                uint32_t gss_flags)
2850 {
2851         unsigned int orig_length = in_data->length;
2852         unsigned int base_cksum_size = GSSAPI_CHECKSUM_SIZE;
2853         char *gss_cksum = NULL;
2854
2855         if (orig_length) {
2856                 /* Extra length field for delgated ticket. */
2857                 base_cksum_size += 4;
2858         }
2859
2860         if ((unsigned int)base_cksum_size + orig_length <
2861                         (unsigned int)base_cksum_size) {
2862                 return EINVAL;
2863         }
2864
2865         gss_cksum = (char *)SMB_MALLOC(base_cksum_size + orig_length);
2866         if (gss_cksum == NULL) {
2867                 return ENOMEM;
2868         }
2869
2870         memset(gss_cksum, '\0', base_cksum_size + orig_length);
2871         SIVAL(gss_cksum, 0, GSSAPI_BNDLENGTH);
2872
2873         /*
2874          * GSS_C_NO_CHANNEL_BINDINGS means 16 zero bytes.
2875          * This matches the behavior of heimdal and mit.
2876          *
2877          * And it is needed to work against some closed source
2878          * SMB servers.
2879          *
2880          * See bug #7883
2881          */
2882         memset(&gss_cksum[4], 0x00, GSSAPI_BNDLENGTH);
2883
2884         SIVAL(gss_cksum, 20, gss_flags);
2885
2886         if (orig_length) {
2887                 SSVAL(gss_cksum, 24, 1); /* The Delegation Option identifier */
2888                 SSVAL(gss_cksum, 26, orig_length);
2889                 /* Copy the kerberos KRB_CRED data */
2890                 memcpy(gss_cksum + 28, in_data->data, orig_length);
2891                 free(in_data->data);
2892                 in_data->data = NULL;
2893                 in_data->length = 0;
2894         }
2895         in_data->data = gss_cksum;
2896         in_data->length = base_cksum_size + orig_length;
2897         return 0;
2898 }
2899 #endif
2900
2901 /*
2902  * We can't use krb5_mk_req because w2k wants the service to be in a particular
2903  * format.
2904  */
2905 static krb5_error_code ads_krb5_mk_req(krb5_context context,
2906                                        krb5_auth_context *auth_context,
2907                                        const krb5_flags ap_req_options,
2908                                        const char *principal,
2909                                        krb5_ccache ccache,
2910                                        krb5_data *outbuf,
2911                                        time_t *expire_time,
2912                                        const char *impersonate_princ_s)
2913 {
2914         krb5_error_code retval;
2915         krb5_principal server;
2916         krb5_principal impersonate_princ = NULL;
2917         krb5_creds *credsp;
2918         krb5_creds creds;
2919         krb5_data in_data;
2920         bool creds_ready = false;
2921         int i = 0, maxtries = 3;
2922         bool ok;
2923
2924         ZERO_STRUCT(in_data);
2925
2926         retval = smb_krb5_parse_name(context, principal, &server);
2927         if (retval != 0) {
2928                 DEBUG(1,("ads_krb5_mk_req: Failed to parse principal %s\n", principal));
2929                 return retval;
2930         }
2931
2932         if (impersonate_princ_s) {
2933                 retval = smb_krb5_parse_name(context, impersonate_princ_s,
2934                                              &impersonate_princ);
2935                 if (retval) {
2936                         DEBUG(1,("ads_krb5_mk_req: Failed to parse principal %s\n", impersonate_princ_s));
2937                         goto cleanup_princ;
2938                 }
2939         }
2940
2941         /* obtain ticket & session key */
2942         ZERO_STRUCT(creds);
2943         if ((retval = krb5_copy_principal(context, server, &creds.server))) {
2944                 DEBUG(1,("ads_krb5_mk_req: krb5_copy_principal failed (%s)\n",
2945                          error_message(retval)));
2946                 goto cleanup_princ;
2947         }
2948
2949         retval = krb5_cc_get_principal(context, ccache, &creds.client);
2950         if (retval != 0) {
2951                 /* This can commonly fail on smbd startup with no ticket in the cache.
2952                  * Report at higher level than 1. */
2953                 DEBUG(3,("ads_krb5_mk_req: krb5_cc_get_principal failed (%s)\n",
2954                          error_message(retval)));
2955                 goto cleanup_creds;
2956         }
2957
2958         while (!creds_ready && (i < maxtries)) {
2959
2960                 retval = smb_krb5_get_credentials(context,
2961                                                   ccache,
2962                                                   creds.client,
2963                                                   creds.server,
2964                                                   impersonate_princ,
2965                                                   &credsp);
2966                 if (retval != 0) {
2967                         DBG_WARNING("smb_krb5_get_credentials failed for %s "
2968                                     "(%s)\n",
2969                                     principal,
2970                                     error_message(retval));
2971                         goto cleanup_creds;
2972                 }
2973
2974                 /* cope with ticket being in the future due to clock skew */
2975                 if ((unsigned)credsp->times.starttime > time(NULL)) {
2976                         time_t t = time(NULL);
2977                         int time_offset =(int)((unsigned)credsp->times.starttime-t);
2978                         DEBUG(4,("ads_krb5_mk_req: Advancing clock by %d seconds to cope with clock skew\n", time_offset));
2979                         krb5_set_real_time(context, t + time_offset + 1, 0);
2980                 }
2981
2982                 ok = ads_cleanup_expired_creds(context, ccache, credsp);
2983                 if (!ok) {
2984                         creds_ready = true;
2985                 }
2986
2987                 i++;
2988         }
2989
2990         DBG_DEBUG("Ticket (%s) in ccache (%s:%s) is valid until: (%s - %u)\n",
2991                   principal,
2992                   krb5_cc_get_type(context, ccache),
2993                   krb5_cc_get_name(context, ccache),
2994                   http_timestring(talloc_tos(),
2995                                   (unsigned)credsp->times.endtime),
2996                   (unsigned)credsp->times.endtime);
2997
2998         if (expire_time) {
2999                 *expire_time = (time_t)credsp->times.endtime;
3000         }
3001
3002         /* Allocate the auth_context. */
3003         retval = ads_setup_auth_context(context, auth_context);
3004         if (retval != 0) {
3005                 DBG_WARNING("ads_setup_auth_context failed (%s)\n",
3006                             error_message(retval));
3007                 goto cleanup_creds;
3008         }
3009
3010 #if defined(TKT_FLG_OK_AS_DELEGATE ) && defined(HAVE_KRB5_AUTH_CON_SETUSERUSERKEY) && defined(KRB5_AUTH_CONTEXT_USE_SUBKEY) && defined(HAVE_KRB5_AUTH_CON_SET_REQ_CKSUMTYPE)
3011         {
3012                 uint32_t gss_flags = 0;
3013
3014                 if (credsp->ticket_flags & TKT_FLG_OK_AS_DELEGATE) {
3015                         /*
3016                          * Fetch a forwarded TGT from the KDC so that we can
3017                          * hand off a 2nd ticket as part of the kerberos
3018                          * exchange.
3019                          */
3020
3021                         DBG_INFO("Server marked as OK to delegate to, building "
3022                                  "forwardable TGT\n");
3023
3024                         retval = krb5_auth_con_setuseruserkey(context,
3025                                         *auth_context,
3026                                         &credsp->keyblock );
3027                         if (retval != 0) {
3028                                 DBG_WARNING("krb5_auth_con_setuseruserkey "
3029                                             "failed (%s)\n",
3030                                             error_message(retval)));
3031                                 goto cleanup_creds;
3032                         }
3033
3034                         /* Must use a subkey for forwarded tickets. */
3035                         retval = krb5_auth_con_setflags(context,
3036                                                         *auth_context,
3037                                                         KRB5_AUTH_CONTEXT_USE_SUBKEY);
3038                         if (retval != 0) {
3039                                 DBG_WARNING("krb5_auth_con_setflags failed (%s)\n",
3040                                             error_message(retval)));
3041                                 goto cleanup_creds;
3042                         }
3043
3044                         retval = krb5_fwd_tgt_creds(context,/* Krb5 context [in] */
3045                                 *auth_context,  /* Authentication context [in] */
3046                                 discard_const_p(char, KRB5_TGS_NAME),  /* Ticket service name ("krbtgt") [in] */
3047                                 credsp->client, /* Client principal for the tgt [in] */
3048                                 credsp->server, /* Server principal for the tgt [in] */
3049                                 ccache,         /* Credential cache to use for storage [in] */
3050                                 1,              /* Turn on for "Forwardable ticket" [in] */
3051                                 &in_data );     /* Resulting response [out] */
3052
3053                         if (retval) {
3054                                 DBG_INFO("krb5_fwd_tgt_creds failed (%s)\n",
3055                                          error_message(retval));
3056
3057                                 /*
3058                                  * This is not fatal. Delete the *auth_context and continue
3059                                  * with krb5_mk_req_extended to get a non-forwardable ticket.
3060                                  */
3061
3062                                 if (in_data.data) {
3063                                         free( in_data.data );
3064                                         in_data.data = NULL;
3065                                         in_data.length = 0;
3066                                 }
3067                                 krb5_auth_con_free(context, *auth_context);
3068                                 *auth_context = NULL;
3069                                 retval = ads_setup_auth_context(context, auth_context);
3070                                 if (retval != 0) {
3071                                         DBG_WARNING("ads_setup_auth_context failed (%s)\n",
3072                                                     error_message(retval)));
3073                                         goto cleanup_creds;
3074                                 }
3075                         } else {
3076                                 /* We got a delegated ticket. */
3077                                 gss_flags |= GSS_C_DELEG_FLAG;
3078                         }
3079                 }
3080
3081                 /* Frees and reallocates in_data into a GSS checksum blob. */
3082                 retval = ads_create_gss_checksum(&in_data, gss_flags);
3083                 if (retval != 0) {
3084                         goto cleanup_data;
3085                 }
3086
3087                 /* We always want GSS-checksum types. */
3088                 retval = krb5_auth_con_set_req_cksumtype(context, *auth_context, GSSAPI_CHECKSUM );
3089                 if (retval != 0) {
3090                         DEBUG(1,("krb5_auth_con_set_req_cksumtype failed (%s)\n",
3091                                 error_message(retval)));
3092                         goto cleanup_data;
3093                 }
3094         }
3095 #endif
3096
3097         retval = krb5_mk_req_extended(context, auth_context, ap_req_options,
3098                                       &in_data, credsp, outbuf);
3099         if (retval != 0) {
3100                 DBG_WARNING("krb5_mk_req_extended failed (%s)\n",
3101                             error_message(retval));
3102         }
3103
3104 #if defined(TKT_FLG_OK_AS_DELEGATE ) && defined(HAVE_KRB5_AUTH_CON_SETUSERUSERKEY) && defined(KRB5_AUTH_CONTEXT_USE_SUBKEY) && defined(HAVE_KRB5_AUTH_CON_SET_REQ_CKSUMTYPE)
3105 cleanup_data:
3106 #endif
3107
3108         if (in_data.data) {
3109                 free( in_data.data );
3110                 in_data.length = 0;
3111         }
3112
3113         krb5_free_creds(context, credsp);
3114
3115 cleanup_creds:
3116         krb5_free_cred_contents(context, &creds);
3117
3118 cleanup_princ:
3119         krb5_free_principal(context, server);
3120         if (impersonate_princ) {
3121                 krb5_free_principal(context, impersonate_princ);
3122         }
3123
3124         return retval;
3125 }
3126
3127 /*
3128   get a kerberos5 ticket for the given service
3129 */
3130 int ads_krb5_cli_get_ticket(TALLOC_CTX *mem_ctx,
3131                             const char *principal,
3132                             time_t time_offset,
3133                             DATA_BLOB *ticket,
3134                             DATA_BLOB *session_key_krb5,
3135                             uint32_t extra_ap_opts, const char *ccname,
3136                             time_t *tgs_expire,
3137                             const char *impersonate_princ_s)
3138 {
3139         krb5_error_code retval;
3140         krb5_data packet;
3141         krb5_context context = NULL;
3142         krb5_ccache ccdef = NULL;
3143         krb5_auth_context auth_context = NULL;
3144         krb5_enctype enc_types[] = {
3145 #ifdef HAVE_ENCTYPE_AES256_CTS_HMAC_SHA1_96
3146                 ENCTYPE_AES256_CTS_HMAC_SHA1_96,
3147 #endif
3148 #ifdef HAVE_ENCTYPE_AES128_CTS_HMAC_SHA1_96
3149                 ENCTYPE_AES128_CTS_HMAC_SHA1_96,
3150 #endif
3151                 ENCTYPE_ARCFOUR_HMAC,
3152                 ENCTYPE_DES_CBC_MD5,
3153                 ENCTYPE_DES_CBC_CRC,
3154                 ENCTYPE_NULL};
3155         bool ok;
3156
3157         initialize_krb5_error_table();
3158         retval = krb5_init_context(&context);
3159         if (retval != 0) {
3160                 DBG_WARNING("krb5_init_context failed (%s)\n",
3161                             error_message(retval));
3162                 goto failed;
3163         }
3164
3165         if (time_offset != 0) {
3166                 krb5_set_real_time(context, time(NULL) + time_offset, 0);
3167         }
3168
3169         retval = krb5_cc_resolve(context,
3170                                  ccname ? ccname : krb5_cc_default_name(context),
3171                                  &ccdef);
3172         if (retval != 0) {
3173                 DBG_WARNING("krb5_cc_default failed (%s)\n",
3174                             error_message(retval));
3175                 goto failed;
3176         }
3177
3178         retval = krb5_set_default_tgs_ktypes(context, enc_types);
3179         if (retval != 0) {
3180                 DBG_WARNING("krb5_set_default_tgs_ktypes failed (%s)\n",
3181                             error_message(retval));
3182                 goto failed;
3183         }
3184
3185         retval = ads_krb5_mk_req(context,
3186                                  &auth_context,
3187                                  AP_OPTS_USE_SUBKEY | (krb5_flags)extra_ap_opts,
3188                                  principal,
3189                                  ccdef,
3190                                  &packet,
3191                                  tgs_expire,
3192                                  impersonate_princ_s);
3193         if (retval != 0) {
3194                 goto failed;
3195         }
3196
3197         ok = smb_krb5_get_smb_session_key(mem_ctx,
3198                                           context,
3199                                           auth_context,
3200                                           session_key_krb5,
3201                                           false);
3202         if (!ok) {
3203                 retval = ENOMEM;
3204                 goto failed;
3205         }
3206
3207         *ticket = data_blob_talloc(mem_ctx, packet.data, packet.length);
3208
3209         smb_krb5_free_data_contents(context, &packet);
3210
3211 failed:
3212
3213         if (context) {
3214                 if (ccdef) {
3215                         krb5_cc_close(context, ccdef);
3216                 }
3217                 if (auth_context) {
3218                         krb5_auth_con_free(context, auth_context);
3219                 }
3220                 krb5_free_context(context);
3221         }
3222
3223         return retval;
3224 }
3225
3226 #else /* HAVE_KRB5 */
3227 /* This saves a few linking headaches */
3228 int ads_krb5_cli_get_ticket(TALLOC_CTX *mem_ctx,
3229                             const char *principal,
3230                             time_t time_offset,
3231                             DATA_BLOB *ticket,
3232                             DATA_BLOB *session_key_krb5,
3233                             uint32_t extra_ap_opts, const char *ccname,
3234                             time_t *tgs_expire,
3235                             const char *impersonate_princ_s)
3236 {
3237          DEBUG(0,("NO KERBEROS SUPPORT\n"));
3238          return 1;
3239 }
3240
3241 #endif /* HAVE_KRB5 */