source/libsmb/clikrb5.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
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 2 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program; if not, write to the Free Software
  19    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20 */
  21
  22 #include "includes.h"
  23
  24 #ifdef HAVE_KRB5
  25
  26 #ifndef HAVE_KRB5_SET_REAL_TIME
  27 /*
  28  * This function is not in the Heimdal mainline.
  29  */
  30  krb5_error_code krb5_set_real_time(krb5_context context, int32_t seconds, int32_t microseconds)
  31 {
  32         krb5_error_code ret;
  33         int32_t sec, usec;
  34
  35         ret = krb5_us_timeofday(context, &sec, &usec);
  36         if (ret)
  37                 return ret;
  38
  39         context->kdc_sec_offset = seconds - sec;
  40         context->kdc_usec_offset = microseconds - usec;
  41
  42         return 0;
  43 }
  44 #endif
  45
  46 #if defined(HAVE_KRB5_SET_DEFAULT_IN_TKT_ETYPES) && !defined(HAVE_KRB5_SET_DEFAULT_TGS_KTYPES)
  47  krb5_error_code krb5_set_default_tgs_ktypes(krb5_context ctx, const krb5_enctype *enc)
  48 {
  49         return krb5_set_default_in_tkt_etypes(ctx, enc);
  50 }
  51 #endif
  52
  53 #if defined(HAVE_ADDR_TYPE_IN_KRB5_ADDRESS)
  54 /* HEIMDAL */
  55  void setup_kaddr( krb5_address *pkaddr, struct sockaddr *paddr)
  56 {
  57         pkaddr->addr_type = KRB5_ADDRESS_INET;
  58         pkaddr->address.length = sizeof(((struct sockaddr_in *)paddr)->sin_addr);
  59         pkaddr->address.data = (char *)&(((struct sockaddr_in *)paddr)->sin_addr);
  60 }
  61 #elif defined(HAVE_ADDRTYPE_IN_KRB5_ADDRESS)
  62 /* MIT */
  63  void setup_kaddr( krb5_address *pkaddr, struct sockaddr *paddr)
  64 {
  65         pkaddr->addrtype = ADDRTYPE_INET;
  66         pkaddr->length = sizeof(((struct sockaddr_in *)paddr)->sin_addr);
  67         pkaddr->contents = (char *)&(((struct sockaddr_in *)paddr)->sin_addr);
  68 }
  69 #else
  70  __ERROR__XX__UNKNOWN_ADDRTYPE
  71 #endif
  72
  73 #if defined(HAVE_KRB5_PRINCIPAL2SALT) && defined(HAVE_KRB5_USE_ENCTYPE) && defined(HAVE_KRB5_STRING_TO_KEY)
  74  int create_kerberos_key_from_string(krb5_context context,
  75                                         krb5_principal host_princ,
  76                                         krb5_data *password,
  77                                         krb5_keyblock *key,
  78                                         krb5_enctype enctype)
  79 {
  80         int ret;
  81         krb5_data salt;
  82         krb5_encrypt_block eblock;
  83
  84         ret = krb5_principal2salt(context, host_princ, &salt);
  85         if (ret) {
  86                 DEBUG(1,("krb5_principal2salt failed (%s)\n", error_message(ret)));
  87                 return ret;
  88         }
  89         krb5_use_enctype(context, &eblock, enctype);
  90         return krb5_string_to_key(context, &eblock, key, password, &salt);
  91 }
  92 #elif defined(HAVE_KRB5_GET_PW_SALT) && defined(HAVE_KRB5_STRING_TO_KEY_SALT)
  93  int create_kerberos_key_from_string(krb5_context context,
  94                                         krb5_principal host_princ,
  95                                         krb5_data *password,
  96                                         krb5_keyblock *key,
  97                                         krb5_enctype enctype)
  98 {
  99         int ret;
 100         krb5_salt salt;
 101
 102         ret = krb5_get_pw_salt(context, host_princ, &salt);
 103         if (ret) {
 104                 DEBUG(1,("krb5_get_pw_salt failed (%s)\n", error_message(ret)));
 105                 return ret;
 106         }
 107         return krb5_string_to_key_salt(context, enctype, password->data,
 108                 salt, key);
 109 }
 110 #else
 111  __ERROR_XX_UNKNOWN_CREATE_KEY_FUNCTIONS
 112 #endif
 113
 114 #if defined(HAVE_KRB5_GET_PERMITTED_ENCTYPES)
 115 krb5_error_code get_kerberos_allowed_etypes(krb5_context context,
 116                                             krb5_enctype **enctypes)
 117 {
 118         return krb5_get_permitted_enctypes(context, enctypes);
 119 }
 120 #elif defined(HAVE_KRB5_GET_DEFAULT_IN_TKT_ETYPES)
 121 krb5_error_code get_kerberos_allowed_etypes(krb5_context context,
 122                                             krb5_enctype **enctypes)
 123 {
 124         return krb5_get_default_in_tkt_etypes(context, enctypes);
 125 }
 126 #else
 127  __ERROR_XX_UNKNOWN_GET_ENCTYPES_FUNCTIONS
 128 #endif
 129
 130  void free_kerberos_etypes(krb5_context context,
 131                            krb5_enctype *enctypes)
 132 {
 133 #if defined(HAVE_KRB5_FREE_KTYPES)
 134         return krb5_free_ktypes(context, enctypes);
 135 #else
 136         SAFE_FREE(enctypes);
 137         return;
 138 #endif
 139 }
 140
 141 #if defined(HAVE_KRB5_AUTH_CON_SETKEY) && !defined(HAVE_KRB5_AUTH_CON_SETUSERUSERKEY)
 142  krb5_error_code krb5_auth_con_setuseruserkey(krb5_context context,
 143                                         krb5_auth_context auth_context,
 144                                         krb5_keyblock *keyblock)
 145 {
 146         return krb5_auth_con_setkey(context, auth_context, keyblock);
 147 }
 148 #endif
 149
 150  void get_auth_data_from_tkt(DATA_BLOB *auth_data, krb5_ticket *tkt)
 151 {
 152 #if defined(HAVE_KRB5_TKT_ENC_PART2)
 153         if (tkt->enc_part2)
 154                 *auth_data = data_blob(tkt->enc_part2->authorization_data[0]->contents,
 155                         tkt->enc_part2->authorization_data[0]->length);
 156 #else
 157         if (tkt->ticket.authorization_data && tkt->ticket.authorization_data->len)
 158                 *auth_data = data_blob(tkt->ticket.authorization_data->val->ad_data.data,
 159                         tkt->ticket.authorization_data->val->ad_data.length);
 160 #endif
 161 }
 162
 163  krb5_const_principal get_principal_from_tkt(krb5_ticket *tkt)
 164 {
 165 #if defined(HAVE_KRB5_TKT_ENC_PART2)
 166         return tkt->enc_part2->client;
 167 #else
 168         return tkt->client;
 169 #endif
 170 }
 171
 172 #if !defined(HAVE_KRB5_LOCATE_KDC)
 173  krb5_error_code krb5_locate_kdc(krb5_context ctx, const krb5_data *realm, struct sockaddr **addr_pp, int *naddrs, int get_masters)
 174 {
 175         krb5_krbhst_handle hnd;
 176         krb5_krbhst_info *hinfo;
 177         krb5_error_code rc;
 178         int num_kdcs, i;
 179         struct sockaddr *sa;
 180
 181         *addr_pp = NULL;
 182         *naddrs = 0;
 183
 184         rc = krb5_krbhst_init(ctx, realm->data, KRB5_KRBHST_KDC, &hnd);
 185         if (rc) {
 186                 DEBUG(0, ("krb5_locate_kdc: krb5_krbhst_init failed (%s)\n", error_message(rc)));
 187                 return rc;
 188         }
 189
 190         for ( num_kdcs = 0; (rc = krb5_krbhst_next(ctx, hnd, &hinfo) == 0); num_kdcs++)
 191                 ;
 192
 193         krb5_krbhst_reset(ctx, hnd);
 194
 195         if (!num_kdcs) {
 196                 DEBUG(0, ("krb5_locate_kdc: zero kdcs found !\n"));
 197                 krb5_krbhst_free(ctx, hnd);
 198                 return -1;
 199         }
 200
 201         sa = malloc( sizeof(struct sockaddr) * num_kdcs );
 202         if (!sa) {
 203                 DEBUG(0, ("krb5_locate_kdc: malloc failed\n"));
 204                 krb5_krbhst_free(ctx, hnd);
 205                 naddrs = 0;
 206                 return -1;
 207         }
 208
 209         memset(*addr_pp, '\0', sizeof(struct sockaddr) * num_kdcs );
 210
 211         for (i = 0; i < num_kdcs && (rc = krb5_krbhst_next(ctx, hnd, &hinfo) == 0); i++) {
 212                 if (hinfo->ai->ai_family == AF_INET)
 213                         memcpy(&sa[i], hinfo->ai->ai_addr, sizeof(struct sockaddr));
 214         }
 215
 216         krb5_krbhst_free(ctx, hnd);
 217
 218         *naddrs = num_kdcs;
 219         *addr_pp = sa;
 220         return 0;
 221 }
 222 #endif
 223
 224 /*
 225   we can't use krb5_mk_req because w2k wants the service to be in a particular format
 226 */
 227 static krb5_error_code krb5_mk_req2(krb5_context context,
 228                                     krb5_auth_context *auth_context,
 229                                     const krb5_flags ap_req_options,
 230                                     const char *principal,
 231                                     krb5_ccache ccache,
 232                                     krb5_data *outbuf)
 233 {
 234         krb5_error_code           retval;
 235         krb5_principal    server;
 236         krb5_creds              * credsp;
 237         krb5_creds                creds;
 238         krb5_data in_data;
 239
 240         retval = krb5_parse_name(context, principal, &server);
 241         if (retval) {
 242                 DEBUG(1,("Failed to parse principal %s\n", principal));
 243                 return retval;
 244         }
 245
 246         /* obtain ticket & session key */
 247         memset((char *)&creds, 0, sizeof(creds));
 248         if ((retval = krb5_copy_principal(context, server, &creds.server))) {
 249                 DEBUG(1,("krb5_copy_principal failed (%s)\n",
 250                          error_message(retval)));
 251                 goto cleanup_princ;
 252         }
 253
 254         if ((retval = krb5_cc_get_principal(context, ccache, &creds.client))) {
 255                 DEBUG(1,("krb5_cc_get_principal failed (%s)\n",
 256                          error_message(retval)));
 257                 goto cleanup_creds;
 258         }
 259
 260         if ((retval = krb5_get_credentials(context, 0,
 261                                            ccache, &creds, &credsp))) {
 262                 DEBUG(1,("krb5_get_credentials failed for %s (%s)\n",
 263                          principal, error_message(retval)));
 264                 goto cleanup_creds;
 265         }
 266
 267         /* cope with the ticket being in the future due to clock skew */
 268         if ((unsigned)credsp->times.starttime > time(NULL)) {
 269                 time_t t = time(NULL);
 270                 int time_offset = (unsigned)credsp->times.starttime - t;
 271                 DEBUG(4,("Advancing clock by %d seconds to cope with clock skew\n", time_offset));
 272                 krb5_set_real_time(context, t + time_offset + 1, 0);
 273         }
 274
 275         in_data.length = 0;
 276         retval = krb5_mk_req_extended(context, auth_context, ap_req_options,
 277                                       &in_data, credsp, outbuf);
 278         if (retval) {
 279                 DEBUG(1,("krb5_mk_req_extended failed (%s)\n",
 280                          error_message(retval)));
 281         }
 282
 283         krb5_free_creds(context, credsp);
 284
 285 cleanup_creds:
 286         krb5_free_cred_contents(context, &creds);
 287
 288 cleanup_princ:
 289         krb5_free_principal(context, server);
 290
 291         return retval;
 292 }
 293
 294 /*
 295   get a kerberos5 ticket for the given service
 296 */
 297 DATA_BLOB krb5_get_ticket(const char *principal, time_t time_offset)
 298 {
 299         krb5_error_code retval;
 300         krb5_data packet;
 301         krb5_ccache ccdef;
 302         krb5_context context;
 303         krb5_auth_context auth_context = NULL;
 304         DATA_BLOB ret;
 305         krb5_enctype enc_types[] = {
 306 #ifdef ENCTYPE_ARCFOUR_HMAC
 307                 ENCTYPE_ARCFOUR_HMAC,
 308 #endif
 309                                     ENCTYPE_DES_CBC_MD5,
 310                                     ENCTYPE_DES_CBC_CRC,
 311                                     ENCTYPE_NULL};
 312
 313         retval = krb5_init_context(&context);
 314         if (retval) {
 315                 DEBUG(1,("krb5_init_context failed (%s)\n",
 316                          error_message(retval)));
 317                 goto failed;
 318         }
 319
 320         if (time_offset != 0) {
 321                 krb5_set_real_time(context, time(NULL) + time_offset, 0);
 322         }
 323
 324         if ((retval = krb5_cc_default(context, &ccdef))) {
 325                 DEBUG(1,("krb5_cc_default failed (%s)\n",
 326                          error_message(retval)));
 327                 goto failed;
 328         }
 329
 330         if ((retval = krb5_set_default_tgs_ktypes(context, enc_types))) {
 331                 DEBUG(1,("krb5_set_default_tgs_ktypes failed (%s)\n",
 332                          error_message(retval)));
 333                 goto failed;
 334         }
 335
 336         if ((retval = krb5_mk_req2(context,
 337                                    &auth_context,
 338                                    0,
 339                                    principal,
 340                                    ccdef, &packet))) {
 341                 goto failed;
 342         }
 343
 344         ret = data_blob(packet.data, packet.length);
 345 /* Hmm, heimdal dooesn't have this - what's the correct call? */
 346 /*      krb5_free_data_contents(context, &packet); */
 347         krb5_free_context(context);
 348         return ret;
 349
 350 failed:
 351         if ( context )
 352                 krb5_free_context(context);
 353
 354         return data_blob(NULL, 0);
 355 }
 356
 357 #else /* HAVE_KRB5 */
 358  /* this saves a few linking headaches */
 359  DATA_BLOB krb5_get_ticket(const char *principal, time_t time_offset)
 360  {
 361          DEBUG(0,("NO KERBEROS SUPPORT\n"));
 362          return data_blob(NULL, 0);
 363  }
 364 #endif