1/* ocsp_ext.c */ 2/* Written by Tom Titchener <Tom_Titchener@groove.net> for the OpenSSL 3 * project. */ 4 5/* History: 6 This file was transfered to Richard Levitte from CertCo by Kathy 7 Weinhold in mid-spring 2000 to be included in OpenSSL or released 8 as a patch kit. */ 9 10/* ==================================================================== 11 * Copyright (c) 1998-2000 The OpenSSL Project. All rights reserved. 12 * 13 * Redistribution and use in source and binary forms, with or without 14 * modification, are permitted provided that the following conditions 15 * are met: 16 * 17 * 1. Redistributions of source code must retain the above copyright 18 * notice, this list of conditions and the following disclaimer. 19 * 20 * 2. Redistributions in binary form must reproduce the above copyright 21 * notice, this list of conditions and the following disclaimer in 22 * the documentation and/or other materials provided with the 23 * distribution. 24 * 25 * 3. All advertising materials mentioning features or use of this 26 * software must display the following acknowledgment: 27 * "This product includes software developed by the OpenSSL Project 28 * for use in the OpenSSL Toolkit. (http://www.openssl.org/)" 29 * 30 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to 31 * endorse or promote products derived from this software without 32 * prior written permission. For written permission, please contact 33 * openssl-core@openssl.org. 34 * 35 * 5. Products derived from this software may not be called "OpenSSL" 36 * nor may "OpenSSL" appear in their names without prior written 37 * permission of the OpenSSL Project. 38 * 39 * 6. Redistributions of any form whatsoever must retain the following 40 * acknowledgment: 41 * "This product includes software developed by the OpenSSL Project 42 * for use in the OpenSSL Toolkit (http://www.openssl.org/)" 43 * 44 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY 45 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 46 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 47 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR 48 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 49 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 50 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 51 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 52 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 53 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 54 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED 55 * OF THE POSSIBILITY OF SUCH DAMAGE. 56 * ==================================================================== 57 * 58 * This product includes cryptographic software written by Eric Young 59 * (eay@cryptsoft.com). This product includes software written by Tim 60 * Hudson (tjh@cryptsoft.com). 61 * 62 */ 63 64#include <stdio.h> 65#include <cryptlib.h> 66#include <openssl/objects.h> 67#include <openssl/x509.h> 68#include <openssl/ocsp.h> 69#include <openssl/rand.h> 70#include <openssl/x509v3.h> 71 72/* Standard wrapper functions for extensions */ 73 74/* OCSP request extensions */ 75 76int OCSP_REQUEST_get_ext_count(OCSP_REQUEST *x) 77 { 78 return(X509v3_get_ext_count(x->tbsRequest->requestExtensions)); 79 } 80 81int OCSP_REQUEST_get_ext_by_NID(OCSP_REQUEST *x, int nid, int lastpos) 82 { 83 return(X509v3_get_ext_by_NID(x->tbsRequest->requestExtensions,nid,lastpos)); 84 } 85 86int OCSP_REQUEST_get_ext_by_OBJ(OCSP_REQUEST *x, ASN1_OBJECT *obj, int lastpos) 87 { 88 return(X509v3_get_ext_by_OBJ(x->tbsRequest->requestExtensions,obj,lastpos)); 89 } 90 91int OCSP_REQUEST_get_ext_by_critical(OCSP_REQUEST *x, int crit, int lastpos) 92 { 93 return(X509v3_get_ext_by_critical(x->tbsRequest->requestExtensions,crit,lastpos)); 94 } 95 96X509_EXTENSION *OCSP_REQUEST_get_ext(OCSP_REQUEST *x, int loc) 97 { 98 return(X509v3_get_ext(x->tbsRequest->requestExtensions,loc)); 99 } 100 101X509_EXTENSION *OCSP_REQUEST_delete_ext(OCSP_REQUEST *x, int loc) 102 { 103 return(X509v3_delete_ext(x->tbsRequest->requestExtensions,loc)); 104 } 105 106void *OCSP_REQUEST_get1_ext_d2i(OCSP_REQUEST *x, int nid, int *crit, int *idx) 107 { 108 return X509V3_get_d2i(x->tbsRequest->requestExtensions, nid, crit, idx); 109 } 110 111int OCSP_REQUEST_add1_ext_i2d(OCSP_REQUEST *x, int nid, void *value, int crit, 112 unsigned long flags) 113 { 114 return X509V3_add1_i2d(&x->tbsRequest->requestExtensions, nid, value, crit, flags); 115 } 116 117int OCSP_REQUEST_add_ext(OCSP_REQUEST *x, X509_EXTENSION *ex, int loc) 118 { 119 return(X509v3_add_ext(&(x->tbsRequest->requestExtensions),ex,loc) != NULL); 120 } 121 122/* Single extensions */ 123 124int OCSP_ONEREQ_get_ext_count(OCSP_ONEREQ *x) 125 { 126 return(X509v3_get_ext_count(x->singleRequestExtensions)); 127 } 128 129int OCSP_ONEREQ_get_ext_by_NID(OCSP_ONEREQ *x, int nid, int lastpos) 130 { 131 return(X509v3_get_ext_by_NID(x->singleRequestExtensions,nid,lastpos)); 132 } 133 134int OCSP_ONEREQ_get_ext_by_OBJ(OCSP_ONEREQ *x, ASN1_OBJECT *obj, int lastpos) 135 { 136 return(X509v3_get_ext_by_OBJ(x->singleRequestExtensions,obj,lastpos)); 137 } 138 139int OCSP_ONEREQ_get_ext_by_critical(OCSP_ONEREQ *x, int crit, int lastpos) 140 { 141 return(X509v3_get_ext_by_critical(x->singleRequestExtensions,crit,lastpos)); 142 } 143 144X509_EXTENSION *OCSP_ONEREQ_get_ext(OCSP_ONEREQ *x, int loc) 145 { 146 return(X509v3_get_ext(x->singleRequestExtensions,loc)); 147 } 148 149X509_EXTENSION *OCSP_ONEREQ_delete_ext(OCSP_ONEREQ *x, int loc) 150 { 151 return(X509v3_delete_ext(x->singleRequestExtensions,loc)); 152 } 153 154void *OCSP_ONEREQ_get1_ext_d2i(OCSP_ONEREQ *x, int nid, int *crit, int *idx) 155 { 156 return X509V3_get_d2i(x->singleRequestExtensions, nid, crit, idx); 157 } 158 159int OCSP_ONEREQ_add1_ext_i2d(OCSP_ONEREQ *x, int nid, void *value, int crit, 160 unsigned long flags) 161 { 162 return X509V3_add1_i2d(&x->singleRequestExtensions, nid, value, crit, flags); 163 } 164 165int OCSP_ONEREQ_add_ext(OCSP_ONEREQ *x, X509_EXTENSION *ex, int loc) 166 { 167 return(X509v3_add_ext(&(x->singleRequestExtensions),ex,loc) != NULL); 168 } 169 170/* OCSP Basic response */ 171 172int OCSP_BASICRESP_get_ext_count(OCSP_BASICRESP *x) 173 { 174 return(X509v3_get_ext_count(x->tbsResponseData->responseExtensions)); 175 } 176 177int OCSP_BASICRESP_get_ext_by_NID(OCSP_BASICRESP *x, int nid, int lastpos) 178 { 179 return(X509v3_get_ext_by_NID(x->tbsResponseData->responseExtensions,nid,lastpos)); 180 } 181 182int OCSP_BASICRESP_get_ext_by_OBJ(OCSP_BASICRESP *x, ASN1_OBJECT *obj, int lastpos) 183 { 184 return(X509v3_get_ext_by_OBJ(x->tbsResponseData->responseExtensions,obj,lastpos)); 185 } 186 187int OCSP_BASICRESP_get_ext_by_critical(OCSP_BASICRESP *x, int crit, int lastpos) 188 { 189 return(X509v3_get_ext_by_critical(x->tbsResponseData->responseExtensions,crit,lastpos)); 190 } 191 192X509_EXTENSION *OCSP_BASICRESP_get_ext(OCSP_BASICRESP *x, int loc) 193 { 194 return(X509v3_get_ext(x->tbsResponseData->responseExtensions,loc)); 195 } 196 197X509_EXTENSION *OCSP_BASICRESP_delete_ext(OCSP_BASICRESP *x, int loc) 198 { 199 return(X509v3_delete_ext(x->tbsResponseData->responseExtensions,loc)); 200 } 201 202void *OCSP_BASICRESP_get1_ext_d2i(OCSP_BASICRESP *x, int nid, int *crit, int *idx) 203 { 204 return X509V3_get_d2i(x->tbsResponseData->responseExtensions, nid, crit, idx); 205 } 206 207int OCSP_BASICRESP_add1_ext_i2d(OCSP_BASICRESP *x, int nid, void *value, int crit, 208 unsigned long flags) 209 { 210 return X509V3_add1_i2d(&x->tbsResponseData->responseExtensions, nid, value, crit, flags); 211 } 212 213int OCSP_BASICRESP_add_ext(OCSP_BASICRESP *x, X509_EXTENSION *ex, int loc) 214 { 215 return(X509v3_add_ext(&(x->tbsResponseData->responseExtensions),ex,loc) != NULL); 216 } 217 218/* OCSP single response extensions */ 219 220int OCSP_SINGLERESP_get_ext_count(OCSP_SINGLERESP *x) 221 { 222 return(X509v3_get_ext_count(x->singleExtensions)); 223 } 224 225int OCSP_SINGLERESP_get_ext_by_NID(OCSP_SINGLERESP *x, int nid, int lastpos) 226 { 227 return(X509v3_get_ext_by_NID(x->singleExtensions,nid,lastpos)); 228 } 229 230int OCSP_SINGLERESP_get_ext_by_OBJ(OCSP_SINGLERESP *x, ASN1_OBJECT *obj, int lastpos) 231 { 232 return(X509v3_get_ext_by_OBJ(x->singleExtensions,obj,lastpos)); 233 } 234 235int OCSP_SINGLERESP_get_ext_by_critical(OCSP_SINGLERESP *x, int crit, int lastpos) 236 { 237 return(X509v3_get_ext_by_critical(x->singleExtensions,crit,lastpos)); 238 } 239 240X509_EXTENSION *OCSP_SINGLERESP_get_ext(OCSP_SINGLERESP *x, int loc) 241 { 242 return(X509v3_get_ext(x->singleExtensions,loc)); 243 } 244 245X509_EXTENSION *OCSP_SINGLERESP_delete_ext(OCSP_SINGLERESP *x, int loc) 246 { 247 return(X509v3_delete_ext(x->singleExtensions,loc)); 248 } 249 250void *OCSP_SINGLERESP_get1_ext_d2i(OCSP_SINGLERESP *x, int nid, int *crit, int *idx) 251 { 252 return X509V3_get_d2i(x->singleExtensions, nid, crit, idx); 253 } 254 255int OCSP_SINGLERESP_add1_ext_i2d(OCSP_SINGLERESP *x, int nid, void *value, int crit, 256 unsigned long flags) 257 { 258 return X509V3_add1_i2d(&x->singleExtensions, nid, value, crit, flags); 259 } 260 261int OCSP_SINGLERESP_add_ext(OCSP_SINGLERESP *x, X509_EXTENSION *ex, int loc) 262 { 263 return(X509v3_add_ext(&(x->singleExtensions),ex,loc) != NULL); 264 } 265 266/* also CRL Entry Extensions */ 267 268ASN1_STRING *ASN1_STRING_encode(ASN1_STRING *s, i2d_of_void *i2d, 269 void *data, STACK_OF(ASN1_OBJECT) *sk) 270 { 271 int i; 272 unsigned char *p, *b = NULL; 273 274 if (data) 275 { 276 if ((i=i2d(data,NULL)) <= 0) goto err; 277 if (!(b=p=OPENSSL_malloc((unsigned int)i))) 278 goto err; 279 if (i2d(data, &p) <= 0) goto err; 280 } 281 else if (sk) 282 { 283 if ((i=i2d_ASN1_SET_OF_ASN1_OBJECT(sk,NULL, 284 (I2D_OF(ASN1_OBJECT))i2d, 285 V_ASN1_SEQUENCE, 286 V_ASN1_UNIVERSAL, 287 IS_SEQUENCE))<=0) goto err; 288 if (!(b=p=OPENSSL_malloc((unsigned int)i))) 289 goto err; 290 if (i2d_ASN1_SET_OF_ASN1_OBJECT(sk,&p,(I2D_OF(ASN1_OBJECT))i2d, 291 V_ASN1_SEQUENCE, 292 V_ASN1_UNIVERSAL, 293 IS_SEQUENCE)<=0) goto err; 294 } 295 else 296 { 297 OCSPerr(OCSP_F_ASN1_STRING_ENCODE,OCSP_R_BAD_DATA); 298 goto err; 299 } 300 if (!s && !(s = ASN1_STRING_new())) goto err; 301 if (!(ASN1_STRING_set(s, b, i))) goto err; 302 OPENSSL_free(b); 303 return s; 304err: 305 if (b) OPENSSL_free(b); 306 return NULL; 307 } 308 309/* Nonce handling functions */ 310 311/* Add a nonce to an extension stack. A nonce can be specificed or if NULL 312 * a random nonce will be generated. 313 * Note: OpenSSL 0.9.7d and later create an OCTET STRING containing the 314 * nonce, previous versions used the raw nonce. 315 */ 316 317static int ocsp_add1_nonce(STACK_OF(X509_EXTENSION) **exts, unsigned char *val, int len) 318 { 319 unsigned char *tmpval; 320 ASN1_OCTET_STRING os; 321 int ret = 0; 322 if (len <= 0) len = OCSP_DEFAULT_NONCE_LENGTH; 323 /* Create the OCTET STRING manually by writing out the header and 324 * appending the content octets. This avoids an extra memory allocation 325 * operation in some cases. Applications should *NOT* do this because 326 * it relies on library internals. 327 */ 328 os.length = ASN1_object_size(0, len, V_ASN1_OCTET_STRING); 329 os.data = OPENSSL_malloc(os.length); 330 if (os.data == NULL) 331 goto err; 332 tmpval = os.data; 333 ASN1_put_object(&tmpval, 0, len, V_ASN1_OCTET_STRING, V_ASN1_UNIVERSAL); 334 if (val) 335 memcpy(tmpval, val, len); 336 else 337 RAND_pseudo_bytes(tmpval, len); 338 if(!X509V3_add1_i2d(exts, NID_id_pkix_OCSP_Nonce, 339 &os, 0, X509V3_ADD_REPLACE)) 340 goto err; 341 ret = 1; 342 err: 343 if (os.data) 344 OPENSSL_free(os.data); 345 return ret; 346 } 347 348 349/* Add nonce to an OCSP request */ 350 351int OCSP_request_add1_nonce(OCSP_REQUEST *req, unsigned char *val, int len) 352 { 353 return ocsp_add1_nonce(&req->tbsRequest->requestExtensions, val, len); 354 } 355 356/* Same as above but for a response */ 357 358int OCSP_basic_add1_nonce(OCSP_BASICRESP *resp, unsigned char *val, int len) 359 { 360 return ocsp_add1_nonce(&resp->tbsResponseData->responseExtensions, val, len); 361 } 362 363/* Check nonce validity in a request and response. 364 * Return value reflects result: 365 * 1: nonces present and equal. 366 * 2: nonces both absent. 367 * 3: nonce present in response only. 368 * 0: nonces both present and not equal. 369 * -1: nonce in request only. 370 * 371 * For most responders clients can check return > 0. 372 * If responder doesn't handle nonces return != 0 may be 373 * necessary. return == 0 is always an error. 374 */ 375 376int OCSP_check_nonce(OCSP_REQUEST *req, OCSP_BASICRESP *bs) 377 { 378 /* 379 * Since we are only interested in the presence or absence of 380 * the nonce and comparing its value there is no need to use 381 * the X509V3 routines: this way we can avoid them allocating an 382 * ASN1_OCTET_STRING structure for the value which would be 383 * freed immediately anyway. 384 */ 385 386 int req_idx, resp_idx; 387 X509_EXTENSION *req_ext, *resp_ext; 388 req_idx = OCSP_REQUEST_get_ext_by_NID(req, NID_id_pkix_OCSP_Nonce, -1); 389 resp_idx = OCSP_BASICRESP_get_ext_by_NID(bs, NID_id_pkix_OCSP_Nonce, -1); 390 /* Check both absent */ 391 if((req_idx < 0) && (resp_idx < 0)) 392 return 2; 393 /* Check in request only */ 394 if((req_idx >= 0) && (resp_idx < 0)) 395 return -1; 396 /* Check in response but not request */ 397 if((req_idx < 0) && (resp_idx >= 0)) 398 return 3; 399 /* Otherwise nonce in request and response so retrieve the extensions */ 400 req_ext = OCSP_REQUEST_get_ext(req, req_idx); 401 resp_ext = OCSP_BASICRESP_get_ext(bs, resp_idx); 402 if(ASN1_OCTET_STRING_cmp(req_ext->value, resp_ext->value)) 403 return 0; 404 return 1; 405 } 406 407/* Copy the nonce value (if any) from an OCSP request to 408 * a response. 409 */ 410 411int OCSP_copy_nonce(OCSP_BASICRESP *resp, OCSP_REQUEST *req) 412 { 413 X509_EXTENSION *req_ext; 414 int req_idx; 415 /* Check for nonce in request */ 416 req_idx = OCSP_REQUEST_get_ext_by_NID(req, NID_id_pkix_OCSP_Nonce, -1); 417 /* If no nonce that's OK */ 418 if (req_idx < 0) return 2; 419 req_ext = OCSP_REQUEST_get_ext(req, req_idx); 420 return OCSP_BASICRESP_add_ext(resp, req_ext, -1); 421 } 422 423X509_EXTENSION *OCSP_crlID_new(char *url, long *n, char *tim) 424 { 425 X509_EXTENSION *x = NULL; 426 OCSP_CRLID *cid = NULL; 427 428 if (!(cid = OCSP_CRLID_new())) goto err; 429 if (url) 430 { 431 if (!(cid->crlUrl = ASN1_IA5STRING_new())) goto err; 432 if (!(ASN1_STRING_set(cid->crlUrl, url, -1))) goto err; 433 } 434 if (n) 435 { 436 if (!(cid->crlNum = ASN1_INTEGER_new())) goto err; 437 if (!(ASN1_INTEGER_set(cid->crlNum, *n))) goto err; 438 } 439 if (tim) 440 { 441 if (!(cid->crlTime = ASN1_GENERALIZEDTIME_new())) goto err; 442 if (!(ASN1_GENERALIZEDTIME_set_string(cid->crlTime, tim))) 443 goto err; 444 } 445 if (!(x = X509_EXTENSION_new())) goto err; 446 if (!(x->object = OBJ_nid2obj(NID_id_pkix_OCSP_CrlID))) goto err; 447 if (!(ASN1_STRING_encode_of(OCSP_CRLID,x->value,i2d_OCSP_CRLID,cid, 448 NULL))) 449 goto err; 450 OCSP_CRLID_free(cid); 451 return x; 452err: 453 if (x) X509_EXTENSION_free(x); 454 if (cid) OCSP_CRLID_free(cid); 455 return NULL; 456 } 457 458/* AcceptableResponses ::= SEQUENCE OF OBJECT IDENTIFIER */ 459X509_EXTENSION *OCSP_accept_responses_new(char **oids) 460 { 461 int nid; 462 STACK_OF(ASN1_OBJECT) *sk = NULL; 463 ASN1_OBJECT *o = NULL; 464 X509_EXTENSION *x = NULL; 465 466 if (!(sk = sk_ASN1_OBJECT_new_null())) goto err; 467 while (oids && *oids) 468 { 469 if ((nid=OBJ_txt2nid(*oids))!=NID_undef&&(o=OBJ_nid2obj(nid))) 470 sk_ASN1_OBJECT_push(sk, o); 471 oids++; 472 } 473 if (!(x = X509_EXTENSION_new())) goto err; 474 if (!(x->object = OBJ_nid2obj(NID_id_pkix_OCSP_acceptableResponses))) 475 goto err; 476 if (!(ASN1_STRING_encode_of(ASN1_OBJECT,x->value,i2d_ASN1_OBJECT,NULL, 477 sk))) 478 goto err; 479 sk_ASN1_OBJECT_pop_free(sk, ASN1_OBJECT_free); 480 return x; 481err: 482 if (x) X509_EXTENSION_free(x); 483 if (sk) sk_ASN1_OBJECT_pop_free(sk, ASN1_OBJECT_free); 484 return NULL; 485 } 486 487/* ArchiveCutoff ::= GeneralizedTime */ 488X509_EXTENSION *OCSP_archive_cutoff_new(char* tim) 489 { 490 X509_EXTENSION *x=NULL; 491 ASN1_GENERALIZEDTIME *gt = NULL; 492 493 if (!(gt = ASN1_GENERALIZEDTIME_new())) goto err; 494 if (!(ASN1_GENERALIZEDTIME_set_string(gt, tim))) goto err; 495 if (!(x = X509_EXTENSION_new())) goto err; 496 if (!(x->object=OBJ_nid2obj(NID_id_pkix_OCSP_archiveCutoff)))goto err; 497 if (!(ASN1_STRING_encode_of(ASN1_GENERALIZEDTIME,x->value, 498 i2d_ASN1_GENERALIZEDTIME,gt,NULL))) goto err; 499 ASN1_GENERALIZEDTIME_free(gt); 500 return x; 501err: 502 if (gt) ASN1_GENERALIZEDTIME_free(gt); 503 if (x) X509_EXTENSION_free(x); 504 return NULL; 505 } 506 507/* per ACCESS_DESCRIPTION parameter are oids, of which there are currently 508 * two--NID_ad_ocsp, NID_id_ad_caIssuers--and GeneralName value. This 509 * method forces NID_ad_ocsp and uniformResourceLocator [6] IA5String. 510 */ 511X509_EXTENSION *OCSP_url_svcloc_new(X509_NAME* issuer, char **urls) 512 { 513 X509_EXTENSION *x = NULL; 514 ASN1_IA5STRING *ia5 = NULL; 515 OCSP_SERVICELOC *sloc = NULL; 516 ACCESS_DESCRIPTION *ad = NULL; 517 518 if (!(sloc = OCSP_SERVICELOC_new())) goto err; 519 if (!(sloc->issuer = X509_NAME_dup(issuer))) goto err; 520 if (urls && *urls && !(sloc->locator = sk_ACCESS_DESCRIPTION_new_null())) goto err; 521 while (urls && *urls) 522 { 523 if (!(ad = ACCESS_DESCRIPTION_new())) goto err; 524 if (!(ad->method=OBJ_nid2obj(NID_ad_OCSP))) goto err; 525 if (!(ad->location = GENERAL_NAME_new())) goto err; 526 if (!(ia5 = ASN1_IA5STRING_new())) goto err; 527 if (!ASN1_STRING_set((ASN1_STRING*)ia5, *urls, -1)) goto err; 528 ad->location->type = GEN_URI; 529 ad->location->d.ia5 = ia5; 530 if (!sk_ACCESS_DESCRIPTION_push(sloc->locator, ad)) goto err; 531 urls++; 532 } 533 if (!(x = X509_EXTENSION_new())) goto err; 534 if (!(x->object = OBJ_nid2obj(NID_id_pkix_OCSP_serviceLocator))) 535 goto err; 536 if (!(ASN1_STRING_encode_of(OCSP_SERVICELOC,x->value, 537 i2d_OCSP_SERVICELOC,sloc,NULL))) goto err; 538 OCSP_SERVICELOC_free(sloc); 539 return x; 540err: 541 if (x) X509_EXTENSION_free(x); 542 if (sloc) OCSP_SERVICELOC_free(sloc); 543 return NULL; 544 } 545 546