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 2002/09/04 16:26:04 joda 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, j;
  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     i = addr->len;
  53     addr->len += n;
  54     tmp = realloc(addr->val, addr->len * sizeof(*addr->val));
  55     if (tmp == NULL) {
  56         krb5_set_error_string(context, "malloc: out of memory");
  57         ret = ENOMEM;
  58         goto fail;
  59     }
  60     addr->val = tmp;
  61     for (j = i; j < addr->len; ++j) {
  62         addr->val[i].addr_type = 0;
  63         krb5_data_zero(&addr->val[i].address);
  64     }
  65     for (a = ai; a != NULL; a = a->ai_next) {
  66         ret = krb5_sockaddr2address (context, a->ai_addr, &addr->val[i]);
  67         if (ret == 0)
  68             ++i;
  69         else if (ret == KRB5_PROG_ATYPE_NOSUPP)
  70             krb5_clear_error_string (context);
  71         else
  72             goto fail;
  73     }
  74     addr->len = i;
  75     return 0;
  76 fail:
  77     krb5_free_addresses (context, addr);
  78     return ret;
  79 }
  80
  81 /*
  82  * Forward credentials for `client' to host `hostname`,
  83  * making them forwardable if `forwardable', and returning the
  84  * blob of data to sent in `out_data'.
  85  * If hostname == NULL, pick it from `server'
  86  */
  87
  88 krb5_error_code
  89 krb5_fwd_tgt_creds (krb5_context        context,
  90                     krb5_auth_context   auth_context,
  91                     const char          *hostname,
  92                     krb5_principal      client,
  93                     krb5_principal      server,
  94                     krb5_ccache         ccache,
  95                     int                 forwardable,
  96                     krb5_data           *out_data)
  97 {
  98     krb5_flags flags = 0;
  99     krb5_creds creds;
 100     krb5_error_code ret;
 101     krb5_const_realm client_realm;
 102
 103     flags |= KDC_OPT_FORWARDED;
 104
 105     if (forwardable)
 106         flags |= KDC_OPT_FORWARDABLE;
 107
 108     if (hostname == NULL &&
 109         krb5_principal_get_type(context, server) == KRB5_NT_SRV_HST) {
 110         const char *inst = krb5_principal_get_comp_string(context, server, 0);
 111         const char *host = krb5_principal_get_comp_string(context, server, 1);
 112
 113         if (inst != NULL &&
 114             strcmp(inst, "host") == 0 &&
 115             host != NULL &&
 116             krb5_principal_get_comp_string(context, server, 2) == NULL)
 117             hostname = host;
 118     }
 119
 120     client_realm = krb5_principal_get_realm(context, client);
 121
 122     memset (&creds, 0, sizeof(creds));
 123     creds.client = client;
 124
 125     ret = krb5_build_principal(context,
 126                                &creds.server,
 127                                strlen(client_realm),
 128                                client_realm,
 129                                KRB5_TGS_NAME,
 130                                client_realm,
 131                                NULL);
 132     if (ret)
 133         return ret;
 134
 135     ret = krb5_get_forwarded_creds (context,
 136                                     auth_context,
 137                                     ccache,
 138                                     flags,
 139                                     hostname,
 140                                     &creds,
 141                                     out_data);
 142     return ret;
 143 }
 144
 145 /*
 146  *
 147  */
 148
 149 krb5_error_code
 150 krb5_get_forwarded_creds (krb5_context      context,
 151                           krb5_auth_context auth_context,
 152                           krb5_ccache       ccache,
 153                           krb5_flags        flags,
 154                           const char        *hostname,
 155                           krb5_creds        *in_creds,
 156                           krb5_data         *out_data)
 157 {
 158     krb5_error_code ret;
 159     krb5_creds *out_creds;
 160     krb5_addresses addrs;
 161     KRB_CRED cred;
 162     KrbCredInfo *krb_cred_info;
 163     EncKrbCredPart enc_krb_cred_part;
 164     size_t len;
 165     unsigned char *buf;
 166     size_t buf_size;
 167     int32_t sec, usec;
 168     krb5_kdc_flags kdc_flags;
 169     krb5_crypto crypto;
 170     struct addrinfo *ai;
 171     int save_errno;
 172     krb5_keyblock *key;
 173
 174     addrs.len = 0;
 175     addrs.val = NULL;
 176
 177     ret = getaddrinfo (hostname, NULL, NULL, &ai);
 178     if (ret) {
 179         save_errno = errno;
 180         krb5_set_error_string(context, "resolving %s: %s",
 181                               hostname, gai_strerror(ret));
 182         return krb5_eai_to_heim_errno(ret, save_errno);
 183     }
 184
 185     ret = add_addrs (context, &addrs, ai);
 186     freeaddrinfo (ai);
 187     if (ret)
 188         return ret;
 189
 190     kdc_flags.i = flags;
 191
 192     ret = krb5_get_kdc_cred (context,
 193                              ccache,
 194                              kdc_flags,
 195                              &addrs,
 196                              NULL,
 197                              in_creds,
 198                              &out_creds);
 199     krb5_free_addresses (context, &addrs);
 200     if (ret) {
 201         return ret;
 202     }
 203
 204     memset (&cred, 0, sizeof(cred));
 205     cred.pvno = 5;
 206     cred.msg_type = krb_cred;
 207     ALLOC_SEQ(&cred.tickets, 1);
 208     if (cred.tickets.val == NULL) {
 209         ret = ENOMEM;
 210         krb5_set_error_string(context, "malloc: out of memory");
 211         goto out2;
 212     }
 213     ret = decode_Ticket(out_creds->ticket.data,
 214                         out_creds->ticket.length,
 215                         cred.tickets.val, &len);
 216     if (ret)
 217         goto out3;
 218
 219     memset (&enc_krb_cred_part, 0, sizeof(enc_krb_cred_part));
 220     ALLOC_SEQ(&enc_krb_cred_part.ticket_info, 1);
 221     if (enc_krb_cred_part.ticket_info.val == NULL) {
 222         ret = ENOMEM;
 223         krb5_set_error_string(context, "malloc: out of memory");
 224         goto out4;
 225     }
 226
 227     krb5_us_timeofday (context, &sec, &usec);
 228
 229     ALLOC(enc_krb_cred_part.timestamp, 1);
 230     if (enc_krb_cred_part.timestamp == NULL) {
 231         ret = ENOMEM;
 232         krb5_set_error_string(context, "malloc: out of memory");
 233         goto out4;
 234     }
 235     *enc_krb_cred_part.timestamp = sec;
 236     ALLOC(enc_krb_cred_part.usec, 1);
 237     if (enc_krb_cred_part.usec == NULL) {
 238         ret = ENOMEM;
 239         krb5_set_error_string(context, "malloc: out of memory");
 240         goto out4;
 241     }
 242     *enc_krb_cred_part.usec      = usec;
 243
 244     if (auth_context->local_address && auth_context->local_port) {
 245         krb5_boolean noaddr;
 246         const krb5_realm *realm;
 247
 248         realm = krb5_princ_realm(context, out_creds->server);
 249         krb5_appdefault_boolean(context, NULL, *realm, "no-addresses", FALSE,
 250                                 &noaddr);
 251         if (!noaddr) {
 252             ret = krb5_make_addrport (context,
 253                                       &enc_krb_cred_part.s_address,
 254                                       auth_context->local_address,
 255                                       auth_context->local_port);
 256             if (ret)
 257                 goto out4;
 258         }
 259     }
 260
 261     if (auth_context->remote_address) {
 262         if (auth_context->remote_port) {
 263             krb5_boolean noaddr;
 264             const krb5_realm *realm;
 265
 266             realm = krb5_princ_realm(context, out_creds->server);
 267             krb5_appdefault_boolean(context, NULL, *realm, "no-addresses",
 268                                     FALSE, &noaddr);
 269             if (!noaddr) {
 270                 ret = krb5_make_addrport (context,
 271                                           &enc_krb_cred_part.r_address,
 272                                           auth_context->remote_address,
 273                                           auth_context->remote_port);
 274                 if (ret)
 275                     goto out4;
 276             }
 277         } else {
 278             ALLOC(enc_krb_cred_part.r_address, 1);
 279             if (enc_krb_cred_part.r_address == NULL) {
 280                 ret = ENOMEM;
 281                 krb5_set_error_string(context, "malloc: out of memory");
 282                 goto out4;
 283             }
 284
 285             ret = krb5_copy_address (context, auth_context->remote_address,
 286                                      enc_krb_cred_part.r_address);
 287             if (ret)
 288                 goto out4;
 289         }
 290     }
 291
 292     /* fill ticket_info.val[0] */
 293
 294     enc_krb_cred_part.ticket_info.len = 1;
 295
 296     krb_cred_info = enc_krb_cred_part.ticket_info.val;
 297
 298     copy_EncryptionKey (&out_creds->session, &krb_cred_info->key);
 299     ALLOC(krb_cred_info->prealm, 1);
 300     copy_Realm (&out_creds->client->realm, krb_cred_info->prealm);
 301     ALLOC(krb_cred_info->pname, 1);
 302     copy_PrincipalName(&out_creds->client->name, krb_cred_info->pname);
 303     ALLOC(krb_cred_info->flags, 1);
 304     *krb_cred_info->flags          = out_creds->flags.b;
 305     ALLOC(krb_cred_info->authtime, 1);
 306     *krb_cred_info->authtime       = out_creds->times.authtime;
 307     ALLOC(krb_cred_info->starttime, 1);
 308     *krb_cred_info->starttime      = out_creds->times.starttime;
 309     ALLOC(krb_cred_info->endtime, 1);
 310     *krb_cred_info->endtime        = out_creds->times.endtime;
 311     ALLOC(krb_cred_info->renew_till, 1);
 312     *krb_cred_info->renew_till = out_creds->times.renew_till;
 313     ALLOC(krb_cred_info->srealm, 1);
 314     copy_Realm (&out_creds->server->realm, krb_cred_info->srealm);
 315     ALLOC(krb_cred_info->sname, 1);
 316     copy_PrincipalName (&out_creds->server->name, krb_cred_info->sname);
 317     ALLOC(krb_cred_info->caddr, 1);
 318     copy_HostAddresses (&out_creds->addresses, krb_cred_info->caddr);
 319
 320     krb5_free_creds (context, out_creds);
 321
 322     /* encode EncKrbCredPart */
 323
 324     ASN1_MALLOC_ENCODE(EncKrbCredPart, buf, buf_size,
 325                        &enc_krb_cred_part, &len, ret);
 326     free_EncKrbCredPart (&enc_krb_cred_part);
 327     if (ret) {
 328         free_KRB_CRED(&cred);
 329         return ret;
 330     }
 331     if(buf_size != len)
 332         krb5_abortx(context, "internal error in ASN.1 encoder");
 333
 334     if (auth_context->local_subkey)
 335         key = auth_context->local_subkey;
 336     else if (auth_context->remote_subkey)
 337         key = auth_context->remote_subkey;
 338     else
 339         key = auth_context->keyblock;
 340
 341     ret = krb5_crypto_init(context, key, 0, &crypto);
 342     if (ret) {
 343         free(buf);
 344         free_KRB_CRED(&cred);
 345         return ret;
 346     }
 347     ret = krb5_encrypt_EncryptedData (context,
 348                                       crypto,
 349                                       KRB5_KU_KRB_CRED,
 350                                       buf,
 351                                       len,
 352                                       0,
 353                                       &cred.enc_part);
 354     free(buf);
 355     krb5_crypto_destroy(context, crypto);
 356     if (ret) {
 357         free_KRB_CRED(&cred);
 358         return ret;
 359     }
 360
 361     ASN1_MALLOC_ENCODE(KRB_CRED, buf, buf_size, &cred, &len, ret);
 362     free_KRB_CRED (&cred);
 363     if (ret)
 364         return ret;
 365     if(buf_size != len)
 366         krb5_abortx(context, "internal error in ASN.1 encoder");
 367     out_data->length = len;
 368     out_data->data   = buf;
 369     return 0;
 370 out4:
 371     free_EncKrbCredPart(&enc_krb_cred_part);
 372 out3:
 373     free_KRB_CRED(&cred);
 374 out2:
 375     krb5_free_creds (context, out_creds);
 376     return ret;
 377 }