1/* 2 * Copyright (c) 1997 - 2004 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 36static krb5_error_code 37add_addrs(krb5_context context, 38 krb5_addresses *addr, 39 struct addrinfo *ai) 40{ 41 krb5_error_code ret; 42 unsigned n, i; 43 void *tmp; 44 struct addrinfo *a; 45 46 n = 0; 47 for (a = ai; a != NULL; a = a->ai_next) 48 ++n; 49 50 tmp = realloc(addr->val, (addr->len + n) * sizeof(*addr->val)); 51 if (tmp == NULL && (addr->len + n) != 0) { 52 ret = ENOMEM; 53 krb5_set_error_message(context, ret, N_("malloc: out of memory", "")); 54 goto fail; 55 } 56 addr->val = tmp; 57 for (i = addr->len; i < (addr->len + n); ++i) { 58 addr->val[i].addr_type = 0; 59 krb5_data_zero(&addr->val[i].address); 60 } 61 i = addr->len; 62 for (a = ai; a != NULL; a = a->ai_next) { 63 krb5_address ad; 64 65 ret = krb5_sockaddr2address (context, a->ai_addr, &ad); 66 if (ret == 0) { 67 if (krb5_address_search(context, &ad, addr)) 68 krb5_free_address(context, &ad); 69 else 70 addr->val[i++] = ad; 71 } 72 else if (ret == KRB5_PROG_ATYPE_NOSUPP) 73 krb5_clear_error_message (context); 74 else 75 goto fail; 76 addr->len = i; 77 } 78 return 0; 79fail: 80 krb5_free_addresses (context, addr); 81 return ret; 82} 83 84/** 85 * Forward credentials for client to host hostname , making them 86 * forwardable if forwardable, and returning the blob of data to sent 87 * in out_data. If hostname == NULL, pick it from server. 88 * 89 * @param context A kerberos 5 context. 90 * @param auth_context the auth context with the key to encrypt the out_data. 91 * @param hostname the host to forward the tickets too. 92 * @param client the client to delegate from. 93 * @param server the server to delegate the credential too. 94 * @param ccache credential cache to use. 95 * @param forwardable make the forwarded ticket forwabledable. 96 * @param out_data the resulting credential. 97 * 98 * @return Return an error code or 0. 99 * 100 * @ingroup krb5_credential 101 */ 102 103KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL 104krb5_fwd_tgt_creds (krb5_context context, 105 krb5_auth_context auth_context, 106 const char *hostname, 107 krb5_principal client, 108 krb5_principal server, 109 krb5_ccache ccache, 110 int forwardable, 111 krb5_data *out_data) 112{ 113 krb5_flags flags = 0; 114 krb5_creds creds; 115 krb5_error_code ret; 116 krb5_const_realm client_realm; 117 118 flags |= KDC_OPT_FORWARDED; 119 120 if (forwardable) 121 flags |= KDC_OPT_FORWARDABLE; 122 123 if (hostname == NULL && 124 krb5_principal_get_type(context, server) == KRB5_NT_SRV_HST) { 125 const char *inst = krb5_principal_get_comp_string(context, server, 0); 126 const char *host = krb5_principal_get_comp_string(context, server, 1); 127 128 if (inst != NULL && 129 strcmp(inst, "host") == 0 && 130 host != NULL && 131 krb5_principal_get_comp_string(context, server, 2) == NULL) 132 hostname = host; 133 } 134 135 client_realm = krb5_principal_get_realm(context, client); 136 137 memset (&creds, 0, sizeof(creds)); 138 creds.client = client; 139 140 ret = krb5_make_principal(context, 141 &creds.server, 142 client_realm, 143 KRB5_TGS_NAME, 144 client_realm, 145 NULL); 146 if (ret) 147 return ret; 148 149 ret = krb5_get_forwarded_creds (context, 150 auth_context, 151 ccache, 152 flags, 153 hostname, 154 &creds, 155 out_data); 156 return ret; 157} 158 159/** 160 * Gets tickets forwarded to hostname. If the tickets that are 161 * forwarded are address-less, the forwarded tickets will also be 162 * address-less. 163 * 164 * If the ticket have any address, hostname will be used for figure 165 * out the address to forward the ticket too. This since this might 166 * use DNS, its insecure and also doesn't represent configured all 167 * addresses of the host. For example, the host might have two 168 * adresses, one IPv4 and one IPv6 address where the later is not 169 * published in DNS. This IPv6 address might be used communications 170 * and thus the resulting ticket useless. 171 * 172 * @param context A kerberos 5 context. 173 * @param auth_context the auth context with the key to encrypt the out_data. 174 * @param ccache credential cache to use 175 * @param flags the flags to control the resulting ticket flags 176 * @param hostname the host to forward the tickets too. 177 * @param in_creds the in client and server ticket names. The client 178 * and server components forwarded to the remote host. 179 * @param out_data the resulting credential. 180 * 181 * @return Return an error code or 0. 182 * 183 * @ingroup krb5_credential 184 */ 185 186KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL 187krb5_get_forwarded_creds (krb5_context context, 188 krb5_auth_context auth_context, 189 krb5_ccache ccache, 190 krb5_flags flags, 191 const char *hostname, 192 krb5_creds *in_creds, 193 krb5_data *out_data) 194{ 195 krb5_error_code ret; 196 krb5_creds *out_creds; 197 krb5_addresses addrs, *paddrs; 198 KRB_CRED cred; 199 KrbCredInfo *krb_cred_info; 200 EncKrbCredPart enc_krb_cred_part; 201 size_t len; 202 unsigned char *buf; 203 size_t buf_size; 204 krb5_kdc_flags kdc_flags; 205 krb5_crypto crypto; 206 struct addrinfo *ai; 207 krb5_creds *ticket; 208 209 paddrs = NULL; 210 addrs.len = 0; 211 addrs.val = NULL; 212 213 if (auth_context->keyblock == NULL) { 214 krb5_set_error_message(context, KRB5KDC_ERR_NULL_KEY, N_("auth context is missing session key", "")); 215 return KRB5KDC_ERR_NULL_KEY; 216 } 217 218 219 ret = krb5_get_credentials(context, 0, ccache, in_creds, &ticket); 220 if(ret == 0) { 221 if (ticket->addresses.len) 222 paddrs = &addrs; 223 krb5_free_creds (context, ticket); 224 } else { 225 krb5_boolean noaddr; 226 krb5_appdefault_boolean(context, NULL, 227 krb5_principal_get_realm(context, 228 in_creds->client), 229 "no-addresses", KRB5_ADDRESSLESS_DEFAULT, 230 &noaddr); 231 if (!noaddr) 232 paddrs = &addrs; 233 } 234 235 /* 236 * If tickets have addresses, get the address of the remote host. 237 */ 238 239 if (paddrs != NULL) { 240 241 ret = getaddrinfo (hostname, NULL, NULL, &ai); 242 if (ret) { 243 krb5_error_code ret2 = krb5_eai_to_heim_errno(ret, errno); 244 krb5_set_error_message(context, ret2, 245 N_("resolving host %s failed: %s", 246 "hostname, error"), 247 hostname, gai_strerror(ret)); 248 return ret2; 249 } 250 251 ret = add_addrs (context, &addrs, ai); 252 freeaddrinfo (ai); 253 if (ret) 254 return ret; 255 } 256 257 kdc_flags.b = int2KDCOptions(flags); 258 259 ret = krb5_get_kdc_cred (context, 260 ccache, 261 kdc_flags, 262 paddrs, 263 NULL, 264 in_creds, 265 &out_creds); 266 krb5_free_addresses (context, &addrs); 267 if (ret) 268 return ret; 269 270 memset (&cred, 0, sizeof(cred)); 271 cred.pvno = 5; 272 cred.msg_type = krb_cred; 273 ALLOC_SEQ(&cred.tickets, 1); 274 if (cred.tickets.val == NULL) { 275 ret = ENOMEM; 276 krb5_set_error_message(context, ret, N_("malloc: out of memory", "")); 277 goto out2; 278 } 279 ret = decode_Ticket(out_creds->ticket.data, 280 out_creds->ticket.length, 281 cred.tickets.val, &len); 282 if (ret) 283 goto out3; 284 285 memset (&enc_krb_cred_part, 0, sizeof(enc_krb_cred_part)); 286 ALLOC_SEQ(&enc_krb_cred_part.ticket_info, 1); 287 if (enc_krb_cred_part.ticket_info.val == NULL) { 288 ret = ENOMEM; 289 krb5_set_error_message(context, ret, N_("malloc: out of memory", "")); 290 goto out4; 291 } 292 293 if (auth_context->flags & KRB5_AUTH_CONTEXT_DO_TIME) { 294 krb5_timestamp sec; 295 int32_t usec; 296 297 krb5_us_timeofday (context, &sec, &usec); 298 299 ALLOC(enc_krb_cred_part.timestamp, 1); 300 if (enc_krb_cred_part.timestamp == NULL) { 301 ret = ENOMEM; 302 krb5_set_error_message(context, ret, N_("malloc: out of memory", "")); 303 goto out4; 304 } 305 *enc_krb_cred_part.timestamp = sec; 306 ALLOC(enc_krb_cred_part.usec, 1); 307 if (enc_krb_cred_part.usec == NULL) { 308 ret = ENOMEM; 309 krb5_set_error_message(context, ret, N_("malloc: out of memory", "")); 310 goto out4; 311 } 312 *enc_krb_cred_part.usec = usec; 313 } else { 314 enc_krb_cred_part.timestamp = NULL; 315 enc_krb_cred_part.usec = NULL; 316 } 317 318 if (auth_context->local_address && auth_context->local_port && paddrs) { 319 320 ret = krb5_make_addrport (context, 321 &enc_krb_cred_part.s_address, 322 auth_context->local_address, 323 auth_context->local_port); 324 if (ret) 325 goto out4; 326 } 327 328 if (auth_context->remote_address) { 329 if (auth_context->remote_port) { 330 krb5_boolean noaddr; 331 krb5_const_realm srealm; 332 333 srealm = krb5_principal_get_realm(context, out_creds->server); 334 /* Is this correct, and should we use the paddrs == NULL 335 trick here as well? Having an address-less ticket may 336 indicate that we don't know our own global address, but 337 it does not necessary mean that we don't know the 338 server's. */ 339 krb5_appdefault_boolean(context, NULL, srealm, "no-addresses", 340 FALSE, &noaddr); 341 if (!noaddr) { 342 ret = krb5_make_addrport (context, 343 &enc_krb_cred_part.r_address, 344 auth_context->remote_address, 345 auth_context->remote_port); 346 if (ret) 347 goto out4; 348 } 349 } else { 350 ALLOC(enc_krb_cred_part.r_address, 1); 351 if (enc_krb_cred_part.r_address == NULL) { 352 ret = ENOMEM; 353 krb5_set_error_message(context, ret, 354 N_("malloc: out of memory", "")); 355 goto out4; 356 } 357 358 ret = krb5_copy_address (context, auth_context->remote_address, 359 enc_krb_cred_part.r_address); 360 if (ret) 361 goto out4; 362 } 363 } 364 365 /* fill ticket_info.val[0] */ 366 367 enc_krb_cred_part.ticket_info.len = 1; 368 369 krb_cred_info = enc_krb_cred_part.ticket_info.val; 370 371 copy_EncryptionKey (&out_creds->session, &krb_cred_info->key); 372 ALLOC(krb_cred_info->prealm, 1); 373 copy_Realm (&out_creds->client->realm, krb_cred_info->prealm); 374 ALLOC(krb_cred_info->pname, 1); 375 copy_PrincipalName(&out_creds->client->name, krb_cred_info->pname); 376 ALLOC(krb_cred_info->flags, 1); 377 *krb_cred_info->flags = out_creds->flags.b; 378 ALLOC(krb_cred_info->authtime, 1); 379 *krb_cred_info->authtime = out_creds->times.authtime; 380 ALLOC(krb_cred_info->starttime, 1); 381 *krb_cred_info->starttime = out_creds->times.starttime; 382 ALLOC(krb_cred_info->endtime, 1); 383 *krb_cred_info->endtime = out_creds->times.endtime; 384 ALLOC(krb_cred_info->renew_till, 1); 385 *krb_cred_info->renew_till = out_creds->times.renew_till; 386 ALLOC(krb_cred_info->srealm, 1); 387 copy_Realm (&out_creds->server->realm, krb_cred_info->srealm); 388 ALLOC(krb_cred_info->sname, 1); 389 copy_PrincipalName (&out_creds->server->name, krb_cred_info->sname); 390 ALLOC(krb_cred_info->caddr, 1); 391 copy_HostAddresses (&out_creds->addresses, krb_cred_info->caddr); 392 393 krb5_free_creds (context, out_creds); 394 395 /* encode EncKrbCredPart */ 396 397 ASN1_MALLOC_ENCODE(EncKrbCredPart, buf, buf_size, 398 &enc_krb_cred_part, &len, ret); 399 free_EncKrbCredPart (&enc_krb_cred_part); 400 if (ret) { 401 free_KRB_CRED(&cred); 402 return ret; 403 } 404 if(buf_size != len) 405 krb5_abortx(context, "internal error in ASN.1 encoder"); 406 407 /* 408 * Here older versions then 0.7.2 of Heimdal used the local or 409 * remote subkey. That is wrong, the session key should be 410 * used. Heimdal 0.7.2 and newer have code to try both in the 411 * receiving end. 412 */ 413 414 ret = krb5_crypto_init(context, auth_context->keyblock, 0, &crypto); 415 if (ret) { 416 free(buf); 417 free_KRB_CRED(&cred); 418 return ret; 419 } 420 ret = krb5_encrypt_EncryptedData (context, 421 crypto, 422 KRB5_KU_KRB_CRED, 423 buf, 424 len, 425 0, 426 &cred.enc_part); 427 free(buf); 428 krb5_crypto_destroy(context, crypto); 429 if (ret) { 430 free_KRB_CRED(&cred); 431 return ret; 432 } 433 434 ASN1_MALLOC_ENCODE(KRB_CRED, buf, buf_size, &cred, &len, ret); 435 free_KRB_CRED (&cred); 436 if (ret) 437 return ret; 438 if(buf_size != len) 439 krb5_abortx(context, "internal error in ASN.1 encoder"); 440 out_data->length = len; 441 out_data->data = buf; 442 return 0; 443 out4: 444 free_EncKrbCredPart(&enc_krb_cred_part); 445 out3: 446 free_KRB_CRED(&cred); 447 out2: 448 krb5_free_creds (context, out_creds); 449 return ret; 450} 451