crypto/heimdal/lib/krb5/get_for_creds.c

   1 /*
   2  * Copyright (c) 1997 - 2002 Kungliga Tekniska Högskolan
   3  * (Royal Institute of Technology, Stockholm, Sweden).
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  *
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  *
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  *
  17  * 3. Neither the name of the Institute nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 #include <krb5_locl.h>
  35
  36 RCSID("$Id: get_for_creds.c,v 1.34.4.1 2004/01/09 00:51:55 lha Exp $");
  37
  38 static krb5_error_code
  39 add_addrs(krb5_context context,
  40           krb5_addresses *addr,
  41           struct addrinfo *ai)
  42 {
  43     krb5_error_code ret;
  44     unsigned n, i;
  45     void *tmp;
  46     struct addrinfo *a;
  47
  48     n = 0;
  49     for (a = ai; a != NULL; a = a->ai_next)
  50         ++n;
  51
  52     tmp = realloc(addr->val, (addr->len + n) * sizeof(*addr->val));
  53     if (tmp == NULL) {
  54         krb5_set_error_string(context, "malloc: out of memory");
  55         ret = ENOMEM;
  56         goto fail;
  57     }
  58     addr->val = tmp;
  59     for (i = addr->len; i < (addr->len + n); ++i) {
  60         addr->val[i].addr_type = 0;
  61         krb5_data_zero(&addr->val[i].address);
  62     }
  63     i = addr->len;
  64     for (a = ai; a != NULL; a = a->ai_next) {
  65         krb5_address ad;
  66
  67         ret = krb5_sockaddr2address (context, a->ai_addr, &ad);
  68         if (ret == 0) {
  69             if (krb5_address_search(context, &ad, addr))
  70                 krb5_free_address(context, &ad);
  71             else
  72                 addr->val[i++] = ad;
  73         }
  74         else if (ret == KRB5_PROG_ATYPE_NOSUPP)
  75             krb5_clear_error_string (context);
  76         else
  77             goto fail;
  78         addr->len = i;
  79     }
  80     return 0;
  81 fail:
  82     krb5_free_addresses (context, addr);
  83     return ret;
  84 }
  85
  86 /*
  87  * Forward credentials for `client' to host `hostname`,
  88  * making them forwardable if `forwardable', and returning the
  89  * blob of data to sent in `out_data'.
  90  * If hostname == NULL, pick it from `server'
  91  */
  92
  93 krb5_error_code
  94 krb5_fwd_tgt_creds (krb5_context        context,
  95                     krb5_auth_context   auth_context,
  96                     const char          *hostname,
  97                     krb5_principal      client,
  98                     krb5_principal      server,
  99                     krb5_ccache         ccache,
 100                     int                 forwardable,
 101                     krb5_data           *out_data)
 102 {
 103     krb5_flags flags = 0;
 104     krb5_creds creds;
 105     krb5_error_code ret;
 106     krb5_const_realm client_realm;
 107
 108     flags |= KDC_OPT_FORWARDED;
 109
 110     if (forwardable)
 111         flags |= KDC_OPT_FORWARDABLE;
 112
 113     if (hostname == NULL &&
 114         krb5_principal_get_type(context, server) == KRB5_NT_SRV_HST) {
 115         const char *inst = krb5_principal_get_comp_string(context, server, 0);
 116         const char *host = krb5_principal_get_comp_string(context, server, 1);
 117
 118         if (inst != NULL &&
 119             strcmp(inst, "host") == 0 &&
 120             host != NULL &&
 121             krb5_principal_get_comp_string(context, server, 2) == NULL)
 122             hostname = host;
 123     }
 124
 125     client_realm = krb5_principal_get_realm(context, client);
 126
 127     memset (&creds, 0, sizeof(creds));
 128     creds.client = client;
 129
 130     ret = krb5_build_principal(context,
 131                                &creds.server,
 132                                strlen(client_realm),
 133                                client_realm,
 134                                KRB5_TGS_NAME,
 135                                client_realm,
 136                                NULL);
 137     if (ret)
 138         return ret;
 139
 140     ret = krb5_get_forwarded_creds (context,
 141                                     auth_context,
 142                                     ccache,
 143                                     flags,
 144                                     hostname,
 145                                     &creds,
 146                                     out_data);
 147     return ret;
 148 }
 149
 150 /*
 151  *
 152  */
 153
 154 krb5_error_code
 155 krb5_get_forwarded_creds (krb5_context      context,
 156                           krb5_auth_context auth_context,
 157                           krb5_ccache       ccache,
 158                           krb5_flags        flags,
 159                           const char        *hostname,
 160                           krb5_creds        *in_creds,
 161                           krb5_data         *out_data)
 162 {
 163     krb5_error_code ret;
 164     krb5_creds *out_creds;
 165     krb5_addresses addrs, *paddrs;
 166     KRB_CRED cred;
 167     KrbCredInfo *krb_cred_info;
 168     EncKrbCredPart enc_krb_cred_part;
 169     size_t len;
 170     unsigned char *buf;
 171     size_t buf_size;
 172     krb5_kdc_flags kdc_flags;
 173     krb5_crypto crypto;
 174     struct addrinfo *ai;
 175     int save_errno;
 176     krb5_keyblock *key;
 177     krb5_creds *ticket;
 178     char *realm;
 179
 180     if (in_creds->client && in_creds->client->realm)
 181         realm = in_creds->client->realm;
 182     else
 183         realm = in_creds->server->realm;
 184
 185     addrs.len = 0;
 186     addrs.val = NULL;
 187     paddrs = &addrs;
 188
 189     /*
 190      * If tickets are address-less, forward address-less tickets.
 191      */
 192
 193     ret = _krb5_get_krbtgt (context,
 194                             ccache,
 195                             realm,
 196                             &ticket);
 197     if(ret == 0) {
 198         if (ticket->addresses.len == 0)
 199             paddrs = NULL;
 200         krb5_free_creds (context, ticket);
 201     }
 202
 203     if (paddrs != NULL) {
 204
 205         ret = getaddrinfo (hostname, NULL, NULL, &ai);
 206         if (ret) {
 207             save_errno = errno;
 208             krb5_set_error_string(context, "resolving %s: %s",
 209                                   hostname, gai_strerror(ret));
 210             return krb5_eai_to_heim_errno(ret, save_errno);
 211         }
 212
 213         ret = add_addrs (context, &addrs, ai);
 214         freeaddrinfo (ai);
 215         if (ret)
 216             return ret;
 217     }
 218
 219     kdc_flags.i = flags;
 220
 221     ret = krb5_get_kdc_cred (context,
 222                              ccache,
 223                              kdc_flags,
 224                              paddrs,
 225                              NULL,
 226                              in_creds,
 227                              &out_creds);
 228     krb5_free_addresses (context, &addrs);
 229     if (ret) {
 230         return ret;
 231     }
 232
 233     memset (&cred, 0, sizeof(cred));
 234     cred.pvno = 5;
 235     cred.msg_type = krb_cred;
 236     ALLOC_SEQ(&cred.tickets, 1);
 237     if (cred.tickets.val == NULL) {
 238         ret = ENOMEM;
 239         krb5_set_error_string(context, "malloc: out of memory");
 240         goto out2;
 241     }
 242     ret = decode_Ticket(out_creds->ticket.data,
 243                         out_creds->ticket.length,
 244                         cred.tickets.val, &len);
 245     if (ret)
 246         goto out3;
 247
 248     memset (&enc_krb_cred_part, 0, sizeof(enc_krb_cred_part));
 249     ALLOC_SEQ(&enc_krb_cred_part.ticket_info, 1);
 250     if (enc_krb_cred_part.ticket_info.val == NULL) {
 251         ret = ENOMEM;
 252         krb5_set_error_string(context, "malloc: out of memory");
 253         goto out4;
 254     }
 255
 256     if (auth_context->flags & KRB5_AUTH_CONTEXT_DO_TIME) {
 257         int32_t sec, usec;
 258
 259         krb5_us_timeofday (context, &sec, &usec);
 260
 261         ALLOC(enc_krb_cred_part.timestamp, 1);
 262         if (enc_krb_cred_part.timestamp == NULL) {
 263             ret = ENOMEM;
 264             krb5_set_error_string(context, "malloc: out of memory");
 265             goto out4;
 266         }
 267         *enc_krb_cred_part.timestamp = sec;
 268         ALLOC(enc_krb_cred_part.usec, 1);
 269         if (enc_krb_cred_part.usec == NULL) {
 270             ret = ENOMEM;
 271             krb5_set_error_string(context, "malloc: out of memory");
 272             goto out4;
 273         }
 274         *enc_krb_cred_part.usec      = usec;
 275     } else {
 276         enc_krb_cred_part.timestamp = NULL;
 277         enc_krb_cred_part.usec = NULL;
 278     }
 279
 280     if (auth_context->local_address && auth_context->local_port) {
 281         krb5_boolean noaddr;
 282         krb5_const_realm realm;
 283
 284         realm = krb5_principal_get_realm(context, out_creds->server);
 285         krb5_appdefault_boolean(context, NULL, realm, "no-addresses", FALSE,
 286                                 &noaddr);
 287         if (!noaddr) {
 288             ret = krb5_make_addrport (context,
 289                                       &enc_krb_cred_part.s_address,
 290                                       auth_context->local_address,
 291                                       auth_context->local_port);
 292             if (ret)
 293                 goto out4;
 294         }
 295     }
 296
 297     if (auth_context->remote_address) {
 298         if (auth_context->remote_port) {
 299             krb5_boolean noaddr;
 300             krb5_const_realm realm;
 301
 302             realm = krb5_principal_get_realm(context, out_creds->server);
 303             krb5_appdefault_boolean(context, NULL, realm, "no-addresses",
 304                                     FALSE, &noaddr);
 305             if (!noaddr) {
 306                 ret = krb5_make_addrport (context,
 307                                           &enc_krb_cred_part.r_address,
 308                                           auth_context->remote_address,
 309                                           auth_context->remote_port);
 310                 if (ret)
 311                     goto out4;
 312             }
 313         } else {
 314             ALLOC(enc_krb_cred_part.r_address, 1);
 315             if (enc_krb_cred_part.r_address == NULL) {
 316                 ret = ENOMEM;
 317                 krb5_set_error_string(context, "malloc: out of memory");
 318                 goto out4;
 319             }
 320
 321             ret = krb5_copy_address (context, auth_context->remote_address,
 322                                      enc_krb_cred_part.r_address);
 323             if (ret)
 324                 goto out4;
 325         }
 326     }
 327
 328     /* fill ticket_info.val[0] */
 329
 330     enc_krb_cred_part.ticket_info.len = 1;
 331
 332     krb_cred_info = enc_krb_cred_part.ticket_info.val;
 333
 334     copy_EncryptionKey (&out_creds->session, &krb_cred_info->key);
 335     ALLOC(krb_cred_info->prealm, 1);
 336     copy_Realm (&out_creds->client->realm, krb_cred_info->prealm);
 337     ALLOC(krb_cred_info->pname, 1);
 338     copy_PrincipalName(&out_creds->client->name, krb_cred_info->pname);
 339     ALLOC(krb_cred_info->flags, 1);
 340     *krb_cred_info->flags          = out_creds->flags.b;
 341     ALLOC(krb_cred_info->authtime, 1);
 342     *krb_cred_info->authtime       = out_creds->times.authtime;
 343     ALLOC(krb_cred_info->starttime, 1);
 344     *krb_cred_info->starttime      = out_creds->times.starttime;
 345     ALLOC(krb_cred_info->endtime, 1);
 346     *krb_cred_info->endtime        = out_creds->times.endtime;
 347     ALLOC(krb_cred_info->renew_till, 1);
 348     *krb_cred_info->renew_till = out_creds->times.renew_till;
 349     ALLOC(krb_cred_info->srealm, 1);
 350     copy_Realm (&out_creds->server->realm, krb_cred_info->srealm);
 351     ALLOC(krb_cred_info->sname, 1);
 352     copy_PrincipalName (&out_creds->server->name, krb_cred_info->sname);
 353     ALLOC(krb_cred_info->caddr, 1);
 354     copy_HostAddresses (&out_creds->addresses, krb_cred_info->caddr);
 355
 356     krb5_free_creds (context, out_creds);
 357
 358     /* encode EncKrbCredPart */
 359
 360     ASN1_MALLOC_ENCODE(EncKrbCredPart, buf, buf_size,
 361                        &enc_krb_cred_part, &len, ret);
 362     free_EncKrbCredPart (&enc_krb_cred_part);
 363     if (ret) {
 364         free_KRB_CRED(&cred);
 365         return ret;
 366     }
 367     if(buf_size != len)
 368         krb5_abortx(context, "internal error in ASN.1 encoder");
 369
 370     if (auth_context->local_subkey)
 371         key = auth_context->local_subkey;
 372     else if (auth_context->remote_subkey)
 373         key = auth_context->remote_subkey;
 374     else
 375         key = auth_context->keyblock;
 376
 377     ret = krb5_crypto_init(context, key, 0, &crypto);
 378     if (ret) {
 379         free(buf);
 380         free_KRB_CRED(&cred);
 381         return ret;
 382     }
 383     ret = krb5_encrypt_EncryptedData (context,
 384                                       crypto,
 385                                       KRB5_KU_KRB_CRED,
 386                                       buf,
 387                                       len,
 388                                       0,
 389                                       &cred.enc_part);
 390     free(buf);
 391     krb5_crypto_destroy(context, crypto);
 392     if (ret) {
 393         free_KRB_CRED(&cred);
 394         return ret;
 395     }
 396
 397     ASN1_MALLOC_ENCODE(KRB_CRED, buf, buf_size, &cred, &len, ret);
 398     free_KRB_CRED (&cred);
 399     if (ret)
 400         return ret;
 401     if(buf_size != len)
 402         krb5_abortx(context, "internal error in ASN.1 encoder");
 403     out_data->length = len;
 404     out_data->data   = buf;
 405     return 0;
 406  out4:
 407     free_EncKrbCredPart(&enc_krb_cred_part);
 408  out3:
 409     free_KRB_CRED(&cred);
 410  out2:
 411     krb5_free_creds (context, out_creds);
 412     return ret;
 413 }