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         krb5_free_ktypes(context, enctypes);
 135         return;
 136 #else
 137         SAFE_FREE(enctypes);
 138         return;
 139 #endif
 140 }
 141
 142 #if defined(HAVE_KRB5_AUTH_CON_SETKEY) && !defined(HAVE_KRB5_AUTH_CON_SETUSERUSERKEY)
 143  krb5_error_code krb5_auth_con_setuseruserkey(krb5_context context,
 144                                         krb5_auth_context auth_context,
 145                                         krb5_keyblock *keyblock)
 146 {
 147         return krb5_auth_con_setkey(context, auth_context, keyblock);
 148 }
 149 #endif
 150
 151  void get_auth_data_from_tkt(DATA_BLOB *auth_data, krb5_ticket *tkt)
 152 {
 153 #if defined(HAVE_KRB5_TKT_ENC_PART2)
 154         if (tkt->enc_part2)
 155                 *auth_data = data_blob(tkt->enc_part2->authorization_data[0]->contents,
 156                         tkt->enc_part2->authorization_data[0]->length);
 157 #else
 158         if (tkt->ticket.authorization_data && tkt->ticket.authorization_data->len)
 159                 *auth_data = data_blob(tkt->ticket.authorization_data->val->ad_data.data,
 160                         tkt->ticket.authorization_data->val->ad_data.length);
 161 #endif
 162 }
 163
 164  krb5_const_principal get_principal_from_tkt(krb5_ticket *tkt)
 165 {
 166 #if defined(HAVE_KRB5_TKT_ENC_PART2)
 167         return tkt->enc_part2->client;
 168 #else
 169         return tkt->client;
 170 #endif
 171 }
 172
 173 #if !defined(HAVE_KRB5_LOCATE_KDC)
 174  krb5_error_code krb5_locate_kdc(krb5_context ctx, const krb5_data *realm, struct sockaddr **addr_pp, int *naddrs, int get_masters)
 175 {
 176         krb5_krbhst_handle hnd;
 177         krb5_krbhst_info *hinfo;
 178         krb5_error_code rc;
 179         int num_kdcs, i;
 180         struct sockaddr *sa;
 181
 182         *addr_pp = NULL;
 183         *naddrs = 0;
 184
 185         rc = krb5_krbhst_init(ctx, realm->data, KRB5_KRBHST_KDC, &hnd);
 186         if (rc) {
 187                 DEBUG(0, ("krb5_locate_kdc: krb5_krbhst_init failed (%s)\n", error_message(rc)));
 188                 return rc;
 189         }
 190
 191         for ( num_kdcs = 0; (rc = krb5_krbhst_next(ctx, hnd, &hinfo) == 0); num_kdcs++)
 192                 ;
 193
 194         krb5_krbhst_reset(ctx, hnd);
 195
 196         if (!num_kdcs) {
 197                 DEBUG(0, ("krb5_locate_kdc: zero kdcs found !\n"));
 198                 krb5_krbhst_free(ctx, hnd);
 199                 return -1;
 200         }
 201
 202         sa = malloc( sizeof(struct sockaddr) * num_kdcs );
 203         if (!sa) {
 204                 DEBUG(0, ("krb5_locate_kdc: malloc failed\n"));
 205                 krb5_krbhst_free(ctx, hnd);
 206                 naddrs = 0;
 207                 return -1;
 208         }
 209
 210         memset(*addr_pp, '\0', sizeof(struct sockaddr) * num_kdcs );
 211
 212         for (i = 0; i < num_kdcs && (rc = krb5_krbhst_next(ctx, hnd, &hinfo) == 0); i++) {
 213                 if (hinfo->ai->ai_family == AF_INET)
 214                         memcpy(&sa[i], hinfo->ai->ai_addr, sizeof(struct sockaddr));
 215         }
 216
 217         krb5_krbhst_free(ctx, hnd);
 218
 219         *naddrs = num_kdcs;
 220         *addr_pp = sa;
 221         return 0;
 222 }
 223 #endif
 224
 225 /*
 226   we can't use krb5_mk_req because w2k wants the service to be in a particular format
 227 */
 228 static krb5_error_code krb5_mk_req2(krb5_context context,
 229                                     krb5_auth_context *auth_context,
 230                                     const krb5_flags ap_req_options,
 231                                     const char *principal,
 232                                     krb5_ccache ccache,
 233                                     krb5_data *outbuf)
 234 {
 235         krb5_error_code           retval;
 236         krb5_principal    server;
 237         krb5_creds              * credsp;
 238         krb5_creds                creds;
 239         krb5_data in_data;
 240
 241         retval = krb5_parse_name(context, principal, &server);
 242         if (retval) {
 243                 DEBUG(1,("Failed to parse principal %s\n", principal));
 244                 return retval;
 245         }
 246
 247         /* obtain ticket & session key */
 248         memset((char *)&creds, 0, sizeof(creds));
 249         if ((retval = krb5_copy_principal(context, server, &creds.server))) {
 250                 DEBUG(1,("krb5_copy_principal failed (%s)\n",
 251                          error_message(retval)));
 252                 goto cleanup_princ;
 253         }
 254
 255         if ((retval = krb5_cc_get_principal(context, ccache, &creds.client))) {
 256                 DEBUG(1,("krb5_cc_get_principal failed (%s)\n",
 257                          error_message(retval)));
 258                 goto cleanup_creds;
 259         }
 260
 261         if ((retval = krb5_get_credentials(context, 0,
 262                                            ccache, &creds, &credsp))) {
 263                 DEBUG(1,("krb5_get_credentials failed for %s (%s)\n",
 264                          principal, error_message(retval)));
 265                 goto cleanup_creds;
 266         }
 267
 268         /* cope with the ticket being in the future due to clock skew */
 269         if ((unsigned)credsp->times.starttime > time(NULL)) {
 270                 time_t t = time(NULL);
 271                 int time_offset = (unsigned)credsp->times.starttime - t;
 272                 DEBUG(4,("Advancing clock by %d seconds to cope with clock skew\n", time_offset));
 273                 krb5_set_real_time(context, t + time_offset + 1, 0);
 274         }
 275
 276         in_data.length = 0;
 277         retval = krb5_mk_req_extended(context, auth_context, ap_req_options,
 278                                       &in_data, credsp, outbuf);
 279         if (retval) {
 280                 DEBUG(1,("krb5_mk_req_extended failed (%s)\n",
 281                          error_message(retval)));
 282         }
 283
 284         krb5_free_creds(context, credsp);
 285
 286 cleanup_creds:
 287         krb5_free_cred_contents(context, &creds);
 288
 289 cleanup_princ:
 290         krb5_free_principal(context, server);
 291
 292         return retval;
 293 }
 294
 295 /*
 296   get a kerberos5 ticket for the given service
 297 */
 298 DATA_BLOB krb5_get_ticket(const char *principal, time_t time_offset)
 299 {
 300         krb5_error_code retval;
 301         krb5_data packet;
 302         krb5_ccache ccdef;
 303         krb5_context context;
 304         krb5_auth_context auth_context = NULL;
 305         DATA_BLOB ret;
 306         krb5_enctype enc_types[] = {
 307 #ifdef ENCTYPE_ARCFOUR_HMAC
 308                 ENCTYPE_ARCFOUR_HMAC,
 309 #endif
 310                                     ENCTYPE_DES_CBC_MD5,
 311                                     ENCTYPE_DES_CBC_CRC,
 312                                     ENCTYPE_NULL};
 313
 314         retval = krb5_init_context(&context);
 315         if (retval) {
 316                 DEBUG(1,("krb5_init_context failed (%s)\n",
 317                          error_message(retval)));
 318                 goto failed;
 319         }
 320
 321         if (time_offset != 0) {
 322                 krb5_set_real_time(context, time(NULL) + time_offset, 0);
 323         }
 324
 325         if ((retval = krb5_cc_default(context, &ccdef))) {
 326                 DEBUG(1,("krb5_cc_default failed (%s)\n",
 327                          error_message(retval)));
 328                 goto failed;
 329         }
 330
 331         if ((retval = krb5_set_default_tgs_ktypes(context, enc_types))) {
 332                 DEBUG(1,("krb5_set_default_tgs_ktypes failed (%s)\n",
 333                          error_message(retval)));
 334                 goto failed;
 335         }
 336
 337         if ((retval = krb5_mk_req2(context,
 338                                    &auth_context,
 339                                    0,
 340                                    principal,
 341                                    ccdef, &packet))) {
 342                 goto failed;
 343         }
 344
 345         ret = data_blob(packet.data, packet.length);
 346 /* Hmm, heimdal dooesn't have this - what's the correct call? */
 347 /*      krb5_free_data_contents(context, &packet); */
 348         krb5_free_context(context);
 349         return ret;
 350
 351 failed:
 352         if ( context )
 353                 krb5_free_context(context);
 354
 355         return data_blob(NULL, 0);
 356 }
 357
 358 #else /* HAVE_KRB5 */
 359  /* this saves a few linking headaches */
 360  DATA_BLOB krb5_get_ticket(const char *principal, time_t time_offset)
 361  {
 362          DEBUG(0,("NO KERBEROS SUPPORT\n"));
 363          return data_blob(NULL, 0);
 364  }
 365 #endif