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