1 /* $OpenBSD: a_int.c,v 1.46 2022/08/28 17:49:25 jsing Exp $ */ 2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) 3 * All rights reserved. 4 * 5 * This package is an SSL implementation written 6 * by Eric Young (eay@cryptsoft.com). 7 * The implementation was written so as to conform with Netscapes SSL. 8 * 9 * This library is free for commercial and non-commercial use as long as 10 * the following conditions are aheared to. The following conditions 11 * apply to all code found in this distribution, be it the RC4, RSA, 12 * lhash, DES, etc., code; not just the SSL code. The SSL documentation 13 * included with this distribution is covered by the same copyright terms 14 * except that the holder is Tim Hudson (tjh@cryptsoft.com). 15 * 16 * Copyright remains Eric Young's, and as such any Copyright notices in 17 * the code are not to be removed. 18 * If this package is used in a product, Eric Young should be given attribution 19 * as the author of the parts of the library used. 20 * This can be in the form of a textual message at program startup or 21 * in documentation (online or textual) provided with the package. 22 * 23 * Redistribution and use in source and binary forms, with or without 24 * modification, are permitted provided that the following conditions 25 * are met: 26 * 1. Redistributions of source code must retain the copyright 27 * notice, this list of conditions and the following disclaimer. 28 * 2. Redistributions in binary form must reproduce the above copyright 29 * notice, this list of conditions and the following disclaimer in the 30 * documentation and/or other materials provided with the distribution. 31 * 3. All advertising materials mentioning features or use of this software 32 * must display the following acknowledgement: 33 * "This product includes cryptographic software written by 34 * Eric Young (eay@cryptsoft.com)" 35 * The word 'cryptographic' can be left out if the rouines from the library 36 * being used are not cryptographic related :-). 37 * 4. If you include any Windows specific code (or a derivative thereof) from 38 * the apps directory (application code) you must include an acknowledgement: 39 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" 40 * 41 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND 42 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 43 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 44 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 45 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 46 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 47 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 49 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 50 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 51 * SUCH DAMAGE. 52 * 53 * The licence and distribution terms for any publically available version or 54 * derivative of this code cannot be changed. i.e. this code cannot simply be 55 * copied and put under another distribution licence 56 * [including the GNU Public Licence.] 57 */ 58 59 #include <limits.h> 60 #include <stdio.h> 61 #include <string.h> 62 63 #include <openssl/asn1.h> 64 #include <openssl/asn1t.h> 65 #include <openssl/bn.h> 66 #include <openssl/buffer.h> 67 #include <openssl/err.h> 68 69 #include "bytestring.h" 70 71 const ASN1_ITEM ASN1_INTEGER_it = { 72 .itype = ASN1_ITYPE_PRIMITIVE, 73 .utype = V_ASN1_INTEGER, 74 .sname = "ASN1_INTEGER", 75 }; 76 77 ASN1_INTEGER * 78 ASN1_INTEGER_new(void) 79 { 80 return (ASN1_INTEGER *)ASN1_item_new(&ASN1_INTEGER_it); 81 } 82 83 static void 84 asn1_aint_clear(ASN1_INTEGER *aint) 85 { 86 freezero(aint->data, aint->length); 87 88 memset(aint, 0, sizeof(*aint)); 89 90 aint->type = V_ASN1_INTEGER; 91 } 92 93 void 94 ASN1_INTEGER_free(ASN1_INTEGER *a) 95 { 96 ASN1_item_free((ASN1_VALUE *)a, &ASN1_INTEGER_it); 97 } 98 99 static int 100 ASN1_INTEGER_valid(const ASN1_INTEGER *a) 101 { 102 return (a != NULL && a->length >= 0); 103 } 104 105 ASN1_INTEGER * 106 ASN1_INTEGER_dup(const ASN1_INTEGER *x) 107 { 108 if (!ASN1_INTEGER_valid(x)) 109 return NULL; 110 111 return ASN1_STRING_dup(x); 112 } 113 114 int 115 ASN1_INTEGER_cmp(const ASN1_INTEGER *a, const ASN1_INTEGER *b) 116 { 117 int ret = 1; 118 119 /* Compare sign, then content. */ 120 if ((a->type & V_ASN1_NEG) == (b->type & V_ASN1_NEG)) 121 ret = ASN1_STRING_cmp(a, b); 122 123 if ((a->type & V_ASN1_NEG) != 0) 124 return -ret; 125 126 return ret; 127 } 128 129 int 130 asn1_aint_get_uint64(CBS *cbs, uint64_t *out_val) 131 { 132 uint64_t val = 0; 133 uint8_t u8; 134 135 *out_val = 0; 136 137 while (CBS_len(cbs) > 0) { 138 if (!CBS_get_u8(cbs, &u8)) 139 return 0; 140 if (val > (UINT64_MAX >> 8)) { 141 ASN1error(ASN1_R_TOO_LARGE); 142 return 0; 143 } 144 val = val << 8 | u8; 145 } 146 147 *out_val = val; 148 149 return 1; 150 } 151 152 int 153 asn1_aint_set_uint64(uint64_t val, uint8_t **out_data, int *out_len) 154 { 155 uint8_t *data = NULL; 156 size_t data_len = 0; 157 int started = 0; 158 uint8_t u8; 159 CBB cbb; 160 int i; 161 int ret = 0; 162 163 if (!CBB_init(&cbb, sizeof(long))) 164 goto err; 165 166 if (out_data == NULL || out_len == NULL) 167 goto err; 168 if (*out_data != NULL || *out_len != 0) 169 goto err; 170 171 for (i = sizeof(uint64_t) - 1; i >= 0; i--) { 172 u8 = (val >> (i * 8)) & 0xff; 173 if (!started && i != 0 && u8 == 0) 174 continue; 175 if (!CBB_add_u8(&cbb, u8)) 176 goto err; 177 started = 1; 178 } 179 180 if (!CBB_finish(&cbb, &data, &data_len)) 181 goto err; 182 if (data_len > INT_MAX) 183 goto err; 184 185 *out_data = data; 186 *out_len = (int)data_len; 187 data = NULL; 188 189 ret = 1; 190 err: 191 CBB_cleanup(&cbb); 192 freezero(data, data_len); 193 194 return ret; 195 } 196 197 int 198 asn1_aint_get_int64(CBS *cbs, int negative, int64_t *out_val) 199 { 200 uint64_t val; 201 202 if (!asn1_aint_get_uint64(cbs, &val)) 203 return 0; 204 205 if (negative) { 206 if (val > (uint64_t)INT64_MIN) { 207 ASN1error(ASN1_R_TOO_SMALL); 208 return 0; 209 } 210 *out_val = (int64_t)-val; 211 } else { 212 if (val > (uint64_t)INT64_MAX) { 213 ASN1error(ASN1_R_TOO_LARGE); 214 return 0; 215 } 216 *out_val = (int64_t)val; 217 } 218 219 return 1; 220 } 221 222 int 223 ASN1_INTEGER_get_uint64(uint64_t *out_val, const ASN1_INTEGER *aint) 224 { 225 uint64_t val; 226 CBS cbs; 227 228 *out_val = 0; 229 230 if (aint == NULL || aint->length < 0) 231 return 0; 232 233 if (aint->type == V_ASN1_NEG_INTEGER) { 234 ASN1error(ASN1_R_ILLEGAL_NEGATIVE_VALUE); 235 return 0; 236 } 237 if (aint->type != V_ASN1_INTEGER) { 238 ASN1error(ASN1_R_WRONG_INTEGER_TYPE); 239 return 0; 240 } 241 242 CBS_init(&cbs, aint->data, aint->length); 243 244 if (!asn1_aint_get_uint64(&cbs, &val)) 245 return 0; 246 247 *out_val = val; 248 249 return 1; 250 } 251 252 int 253 ASN1_INTEGER_set_uint64(ASN1_INTEGER *aint, uint64_t val) 254 { 255 asn1_aint_clear(aint); 256 257 return asn1_aint_set_uint64(val, &aint->data, &aint->length); 258 } 259 260 int 261 ASN1_INTEGER_get_int64(int64_t *out_val, const ASN1_INTEGER *aint) 262 { 263 CBS cbs; 264 265 *out_val = 0; 266 267 if (aint == NULL || aint->length < 0) 268 return 0; 269 270 if (aint->type != V_ASN1_INTEGER && 271 aint->type != V_ASN1_NEG_INTEGER) { 272 ASN1error(ASN1_R_WRONG_INTEGER_TYPE); 273 return 0; 274 } 275 276 CBS_init(&cbs, aint->data, aint->length); 277 278 return asn1_aint_get_int64(&cbs, (aint->type == V_ASN1_NEG_INTEGER), 279 out_val); 280 } 281 282 int 283 ASN1_INTEGER_set_int64(ASN1_INTEGER *aint, int64_t val) 284 { 285 uint64_t uval; 286 287 asn1_aint_clear(aint); 288 289 uval = (uint64_t)val; 290 291 if (val < 0) { 292 aint->type = V_ASN1_NEG_INTEGER; 293 uval = -uval; 294 } 295 296 return asn1_aint_set_uint64(uval, &aint->data, &aint->length); 297 } 298 299 long 300 ASN1_INTEGER_get(const ASN1_INTEGER *aint) 301 { 302 int64_t val; 303 304 if (aint == NULL) 305 return 0; 306 if (!ASN1_INTEGER_get_int64(&val, aint)) 307 return -1; 308 if (val < LONG_MIN || val > LONG_MAX) { 309 /* hmm... a bit ugly, return all ones */ 310 return -1; 311 } 312 313 return (long)val; 314 } 315 316 int 317 ASN1_INTEGER_set(ASN1_INTEGER *aint, long val) 318 { 319 return ASN1_INTEGER_set_int64(aint, val); 320 } 321 322 ASN1_INTEGER * 323 BN_to_ASN1_INTEGER(const BIGNUM *bn, ASN1_INTEGER *ai) 324 { 325 ASN1_INTEGER *ret; 326 int len, j; 327 328 if (ai == NULL) 329 ret = ASN1_INTEGER_new(); 330 else 331 ret = ai; 332 if (ret == NULL) { 333 ASN1error(ERR_R_NESTED_ASN1_ERROR); 334 goto err; 335 } 336 337 if (!ASN1_INTEGER_valid(ret)) 338 goto err; 339 340 if (BN_is_negative(bn)) 341 ret->type = V_ASN1_NEG_INTEGER; 342 else 343 ret->type = V_ASN1_INTEGER; 344 j = BN_num_bits(bn); 345 len = ((j == 0) ? 0 : ((j / 8) + 1)); 346 if (ret->length < len + 4) { 347 unsigned char *new_data = realloc(ret->data, len + 4); 348 if (!new_data) { 349 ASN1error(ERR_R_MALLOC_FAILURE); 350 goto err; 351 } 352 ret->data = new_data; 353 } 354 ret->length = BN_bn2bin(bn, ret->data); 355 356 /* Correct zero case */ 357 if (!ret->length) { 358 ret->data[0] = 0; 359 ret->length = 1; 360 } 361 return (ret); 362 363 err: 364 if (ret != ai) 365 ASN1_INTEGER_free(ret); 366 return (NULL); 367 } 368 369 BIGNUM * 370 ASN1_INTEGER_to_BN(const ASN1_INTEGER *ai, BIGNUM *bn) 371 { 372 BIGNUM *ret; 373 374 if (!ASN1_INTEGER_valid(ai)) 375 return (NULL); 376 377 if ((ret = BN_bin2bn(ai->data, ai->length, bn)) == NULL) 378 ASN1error(ASN1_R_BN_LIB); 379 else if (ai->type == V_ASN1_NEG_INTEGER) 380 BN_set_negative(ret, 1); 381 return (ret); 382 } 383 384 int 385 i2a_ASN1_INTEGER(BIO *bp, const ASN1_INTEGER *a) 386 { 387 int i, n = 0; 388 static const char h[] = "0123456789ABCDEF"; 389 char buf[2]; 390 391 if (a == NULL) 392 return (0); 393 394 if (a->type & V_ASN1_NEG) { 395 if (BIO_write(bp, "-", 1) != 1) 396 goto err; 397 n = 1; 398 } 399 400 if (a->length == 0) { 401 if (BIO_write(bp, "00", 2) != 2) 402 goto err; 403 n += 2; 404 } else { 405 for (i = 0; i < a->length; i++) { 406 if ((i != 0) && (i % 35 == 0)) { 407 if (BIO_write(bp, "\\\n", 2) != 2) 408 goto err; 409 n += 2; 410 } 411 buf[0] = h[((unsigned char)a->data[i] >> 4) & 0x0f]; 412 buf[1] = h[((unsigned char)a->data[i]) & 0x0f]; 413 if (BIO_write(bp, buf, 2) != 2) 414 goto err; 415 n += 2; 416 } 417 } 418 return (n); 419 420 err: 421 return (-1); 422 } 423 424 int 425 a2i_ASN1_INTEGER(BIO *bp, ASN1_INTEGER *bs, char *buf, int size) 426 { 427 int ret = 0; 428 int i, j,k, m,n, again, bufsize; 429 unsigned char *s = NULL, *sp; 430 unsigned char *bufp; 431 int num = 0, slen = 0, first = 1; 432 433 bs->type = V_ASN1_INTEGER; 434 435 bufsize = BIO_gets(bp, buf, size); 436 for (;;) { 437 if (bufsize < 1) 438 goto err_sl; 439 i = bufsize; 440 if (buf[i - 1] == '\n') 441 buf[--i] = '\0'; 442 if (i == 0) 443 goto err_sl; 444 if (buf[i - 1] == '\r') 445 buf[--i] = '\0'; 446 if (i == 0) 447 goto err_sl; 448 if (buf[i - 1] == '\\') { 449 i--; 450 again = 1; 451 } else 452 again = 0; 453 buf[i] = '\0'; 454 if (i < 2) 455 goto err_sl; 456 457 bufp = (unsigned char *)buf; 458 if (first) { 459 first = 0; 460 if ((bufp[0] == '0') && (buf[1] == '0')) { 461 bufp += 2; 462 i -= 2; 463 } 464 } 465 k = 0; 466 if (i % 2 != 0) { 467 ASN1error(ASN1_R_ODD_NUMBER_OF_CHARS); 468 goto err; 469 } 470 i /= 2; 471 if (num + i > slen) { 472 if ((sp = recallocarray(s, slen, num + i, 1)) == NULL) { 473 ASN1error(ERR_R_MALLOC_FAILURE); 474 goto err; 475 } 476 s = sp; 477 slen = num + i; 478 } 479 for (j = 0; j < i; j++, k += 2) { 480 for (n = 0; n < 2; n++) { 481 m = bufp[k + n]; 482 if ((m >= '0') && (m <= '9')) 483 m -= '0'; 484 else if ((m >= 'a') && (m <= 'f')) 485 m = m - 'a' + 10; 486 else if ((m >= 'A') && (m <= 'F')) 487 m = m - 'A' + 10; 488 else { 489 ASN1error(ASN1_R_NON_HEX_CHARACTERS); 490 goto err; 491 } 492 s[num + j] <<= 4; 493 s[num + j] |= m; 494 } 495 } 496 num += i; 497 if (again) 498 bufsize = BIO_gets(bp, buf, size); 499 else 500 break; 501 } 502 bs->length = num; 503 bs->data = s; 504 return (1); 505 506 err_sl: 507 ASN1error(ASN1_R_SHORT_LINE); 508 err: 509 free(s); 510 return (ret); 511 } 512 513 static void 514 asn1_aint_twos_complement(uint8_t *data, size_t data_len) 515 { 516 uint8_t carry = 1; 517 ssize_t i; 518 519 for (i = data_len - 1; i >= 0; i--) { 520 data[i] = (data[i] ^ 0xff) + carry; 521 if (data[i] != 0) 522 carry = 0; 523 } 524 } 525 526 static int 527 asn1_aint_keep_twos_padding(const uint8_t *data, size_t data_len) 528 { 529 size_t i; 530 531 /* 532 * If a two's complement value has a padding byte (0xff) and the rest 533 * of the value is all zeros, the padding byte cannot be removed as when 534 * converted from two's complement this becomes 0x01 (in the place of 535 * the padding byte) followed by the same number of zero bytes. 536 */ 537 if (data_len <= 1 || data[0] != 0xff) 538 return 0; 539 for (i = 1; i < data_len; i++) { 540 if (data[i] != 0) 541 return 0; 542 } 543 return 1; 544 } 545 546 static int 547 i2c_ASN1_INTEGER_cbb(ASN1_INTEGER *aint, CBB *cbb) 548 { 549 uint8_t *data = NULL; 550 size_t data_len = 0; 551 uint8_t padding, val; 552 uint8_t msb; 553 CBS cbs; 554 int ret = 0; 555 556 if (aint->length < 0) 557 goto err; 558 if (aint->data == NULL && aint->length != 0) 559 goto err; 560 561 if ((aint->type & ~V_ASN1_NEG) != V_ASN1_ENUMERATED && 562 (aint->type & ~V_ASN1_NEG) != V_ASN1_INTEGER) 563 goto err; 564 565 CBS_init(&cbs, aint->data, aint->length); 566 567 /* Find the first non-zero byte. */ 568 while (CBS_len(&cbs) > 0) { 569 if (!CBS_peek_u8(&cbs, &val)) 570 goto err; 571 if (val != 0) 572 break; 573 if (!CBS_skip(&cbs, 1)) 574 goto err; 575 } 576 577 /* A zero value is encoded as a single octet. */ 578 if (CBS_len(&cbs) == 0) { 579 if (!CBB_add_u8(cbb, 0)) 580 goto err; 581 goto done; 582 } 583 584 if (!CBS_stow(&cbs, &data, &data_len)) 585 goto err; 586 587 if ((aint->type & V_ASN1_NEG) != 0) 588 asn1_aint_twos_complement(data, data_len); 589 590 /* Topmost bit indicates sign, padding is all zeros or all ones. */ 591 msb = (data[0] >> 7); 592 padding = (msb - 1) & 0xff; 593 594 /* See if we need a padding octet to avoid incorrect sign. */ 595 if (((aint->type & V_ASN1_NEG) == 0 && msb == 1) || 596 ((aint->type & V_ASN1_NEG) != 0 && msb == 0)) { 597 if (!CBB_add_u8(cbb, padding)) 598 goto err; 599 } 600 if (!CBB_add_bytes(cbb, data, data_len)) 601 goto err; 602 603 done: 604 ret = 1; 605 606 err: 607 freezero(data, data_len); 608 609 return ret; 610 } 611 612 int 613 i2c_ASN1_INTEGER(ASN1_INTEGER *aint, unsigned char **pp) 614 { 615 uint8_t *data = NULL; 616 size_t data_len = 0; 617 CBB cbb; 618 int ret = -3; 619 620 if (!CBB_init(&cbb, 0)) 621 goto err; 622 if (!i2c_ASN1_INTEGER_cbb(aint, &cbb)) 623 goto err; 624 if (!CBB_finish(&cbb, &data, &data_len)) 625 goto err; 626 if (data_len > INT_MAX) 627 goto err; 628 629 if (pp != NULL) { 630 if ((uintptr_t)*pp > UINTPTR_MAX - data_len) 631 goto err; 632 memcpy(*pp, data, data_len); 633 *pp += data_len; 634 } 635 636 ret = data_len; 637 638 err: 639 freezero(data, data_len); 640 CBB_cleanup(&cbb); 641 642 return ret; 643 } 644 645 int 646 c2i_ASN1_INTEGER_cbs(ASN1_INTEGER **out_aint, CBS *cbs) 647 { 648 ASN1_INTEGER *aint = NULL; 649 uint8_t *data = NULL; 650 size_t data_len = 0; 651 uint8_t padding, val; 652 uint8_t negative; 653 int ret = 0; 654 655 if (out_aint == NULL) 656 goto err; 657 658 if (*out_aint != NULL) { 659 ASN1_INTEGER_free(*out_aint); 660 *out_aint = NULL; 661 } 662 663 if (CBS_len(cbs) == 0) { 664 /* XXX INVALID ENCODING? */ 665 ASN1error(ERR_R_ASN1_LENGTH_MISMATCH); 666 goto err; 667 } 668 if (!CBS_peek_u8(cbs, &val)) 669 goto err; 670 671 /* Topmost bit indicates sign, padding is all zeros or all ones. */ 672 negative = (val >> 7); 673 padding = ~(negative - 1) & 0xff; 674 675 /* 676 * Ensure that the first 9 bits are not all zero or all one, as per 677 * X.690 section 8.3.2. Remove the padding octet if possible. 678 */ 679 if (CBS_len(cbs) > 1 && val == padding) { 680 if (!asn1_aint_keep_twos_padding(CBS_data(cbs), CBS_len(cbs))) { 681 if (!CBS_get_u8(cbs, &padding)) 682 goto err; 683 if (!CBS_peek_u8(cbs, &val)) 684 goto err; 685 if ((val >> 7) == (padding >> 7)) { 686 /* XXX INVALID ENCODING? */ 687 ASN1error(ERR_R_ASN1_LENGTH_MISMATCH); 688 goto err; 689 } 690 } 691 } 692 693 if (!CBS_stow(cbs, &data, &data_len)) 694 goto err; 695 if (data_len > INT_MAX) 696 goto err; 697 698 if ((aint = ASN1_INTEGER_new()) == NULL) 699 goto err; 700 701 /* 702 * Negative integers are handled as a separate type - convert from 703 * two's complement for internal representation. 704 */ 705 if (negative) { 706 aint->type = V_ASN1_NEG_INTEGER; 707 asn1_aint_twos_complement(data, data_len); 708 } 709 710 aint->data = data; 711 aint->length = (int)data_len; 712 data = NULL; 713 714 *out_aint = aint; 715 aint = NULL; 716 717 ret = 1; 718 719 err: 720 ASN1_INTEGER_free(aint); 721 freezero(data, data_len); 722 723 return ret; 724 } 725 726 ASN1_INTEGER * 727 c2i_ASN1_INTEGER(ASN1_INTEGER **out_aint, const unsigned char **pp, long len) 728 { 729 ASN1_INTEGER *aint = NULL; 730 CBS content; 731 732 if (out_aint != NULL) { 733 ASN1_INTEGER_free(*out_aint); 734 *out_aint = NULL; 735 } 736 737 if (len < 0) { 738 ASN1error(ASN1_R_LENGTH_ERROR); 739 return NULL; 740 } 741 742 CBS_init(&content, *pp, len); 743 744 if (!c2i_ASN1_INTEGER_cbs(&aint, &content)) 745 return NULL; 746 747 *pp = CBS_data(&content); 748 749 if (out_aint != NULL) 750 *out_aint = aint; 751 752 return aint; 753 } 754 755 int 756 i2d_ASN1_INTEGER(ASN1_INTEGER *a, unsigned char **out) 757 { 758 return ASN1_item_i2d((ASN1_VALUE *)a, out, &ASN1_INTEGER_it); 759 } 760 761 ASN1_INTEGER * 762 d2i_ASN1_INTEGER(ASN1_INTEGER **a, const unsigned char **in, long len) 763 { 764 return (ASN1_INTEGER *)ASN1_item_d2i((ASN1_VALUE **)a, in, len, 765 &ASN1_INTEGER_it); 766 } 767 768 /* This is a version of d2i_ASN1_INTEGER that ignores the sign bit of 769 * ASN1 integers: some broken software can encode a positive INTEGER 770 * with its MSB set as negative (it doesn't add a padding zero). 771 */ 772 773 ASN1_INTEGER * 774 d2i_ASN1_UINTEGER(ASN1_INTEGER **a, const unsigned char **pp, long length) 775 { 776 ASN1_INTEGER *ret = NULL; 777 const unsigned char *p; 778 unsigned char *s; 779 long len; 780 int inf, tag, xclass; 781 int i; 782 783 if ((a == NULL) || ((*a) == NULL)) { 784 if ((ret = ASN1_INTEGER_new()) == NULL) 785 return (NULL); 786 } else 787 ret = (*a); 788 789 if (!ASN1_INTEGER_valid(ret)) { 790 i = ERR_R_ASN1_LENGTH_MISMATCH; 791 goto err; 792 } 793 794 p = *pp; 795 inf = ASN1_get_object(&p, &len, &tag, &xclass, length); 796 if (inf & 0x80) { 797 i = ASN1_R_BAD_OBJECT_HEADER; 798 goto err; 799 } 800 801 if (tag != V_ASN1_INTEGER) { 802 i = ASN1_R_EXPECTING_AN_INTEGER; 803 goto err; 804 } 805 806 /* We must malloc stuff, even for 0 bytes otherwise it 807 * signifies a missing NULL parameter. */ 808 if (len < 0 || len > INT_MAX) { 809 i = ERR_R_ASN1_LENGTH_MISMATCH; 810 goto err; 811 } 812 s = malloc(len + 1); 813 if (s == NULL) { 814 i = ERR_R_MALLOC_FAILURE; 815 goto err; 816 } 817 ret->type = V_ASN1_INTEGER; 818 if (len) { 819 if ((*p == 0) && (len != 1)) { 820 p++; 821 len--; 822 } 823 memcpy(s, p, len); 824 p += len; 825 } 826 827 free(ret->data); 828 ret->data = s; 829 ret->length = (int)len; 830 if (a != NULL) 831 (*a) = ret; 832 *pp = p; 833 return (ret); 834 835 err: 836 ASN1error(i); 837 if (a == NULL || *a != ret) 838 ASN1_INTEGER_free(ret); 839 return (NULL); 840 } 841