1 /* crypto/asn1/a_int.c */
2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
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.
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).
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.
23 * Redistribution and use in source and binary forms, with or without
24 * modification, are permitted provided that the following conditions
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)"
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
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.]
60 #include "internal/cryptlib.h"
62 #include <openssl/asn1.h>
63 #include <openssl/bn.h>
64 #include "asn1_locl.h"
66 ASN1_INTEGER *ASN1_INTEGER_dup(const ASN1_INTEGER *x)
68 return ASN1_STRING_dup(x);
71 int ASN1_INTEGER_cmp(const ASN1_INTEGER *x, const ASN1_INTEGER *y)
75 neg = x->type & V_ASN1_NEG;
76 if (neg != (y->type & V_ASN1_NEG)) {
83 ret = ASN1_STRING_cmp(x, y);
92 * This converts a big endian buffer and sign into its content encoding.
93 * This is used for INTEGER and ENUMERATED types.
94 * The internal representation is an ASN1_STRING whose data is a big endian
95 * representation of the value, ignoring the sign. The sign is determined by
96 * the type: if type & V_ASN1_NEG is true it is negative, otherwise positive.
98 * Positive integers are no problem: they are almost the same as the DER
99 * encoding, except if the first byte is >= 0x80 we need to add a zero pad.
101 * Negative integers are a bit trickier...
102 * The DER representation of negative integers is in 2s complement form.
103 * The internal form is converted by complementing each octet and finally
104 * adding one to the result. This can be done less messily with a little trick.
105 * If the internal form has trailing zeroes then they will become FF by the
106 * complement and 0 by the add one (due to carry) so just copy as many trailing
107 * zeros to the destination as there are in the source. The carry will add one
108 * to the last none zero octet: so complement this octet and add one and finally
109 * complement any left over until you get to the start of the string.
111 * Padding is a little trickier too. If the first bytes is > 0x80 then we pad
112 * with 0xff. However if the first byte is 0x80 and one of the following bytes
113 * is non-zero we pad with 0xff. The reason for this distinction is that 0x80
114 * followed by optional zeros isn't padded.
117 static size_t i2c_ibuf(const unsigned char *b, size_t blen, int neg,
122 unsigned char *p, pb = 0;
123 const unsigned char *n;
125 if (b == NULL || blen == 0)
130 if (ret == 1 && i == 0)
132 if (!neg && (i > 127)) {
139 } else if (i == 128) {
141 * Special case: if any other bytes non zero we pad:
142 * otherwise we don't.
144 for (i = 1; i < blen; i++)
165 /* Begin at the end of the encoding */
169 /* Copy zeros to destination as long as source is zero */
170 while (!*n && i > 1) {
175 /* Complement and increment next octet */
176 *(p--) = ((*(n--)) ^ 0xff) + 1;
178 /* Complement any octets left */
180 *(p--) = *(n--) ^ 0xff;
188 * convert content octets into a big endian buffer. Returns the length
189 * of buffer or 0 on error: for malformed INTEGER. If output bufer is
190 * NULL just return length.
193 static size_t c2i_ibuf(unsigned char *b, int *pneg,
194 const unsigned char *p, size_t plen)
198 /* Zero content length is illegal */
200 ASN1err(ASN1_F_C2I_IBUF, ASN1_R_ILLEGAL_ZERO_CONTENT);
206 /* Handle common case where length is 1 octet separately */
210 b[0] = (p[0] ^ 0xFF) + 1;
216 if (p[0] == 0 || p[0] == 0xFF)
220 /* reject illegal padding: first two octets MSB can't match */
221 if (pad && (neg == (p[1] & 0x80))) {
222 ASN1err(ASN1_F_C2I_IBUF, ASN1_R_ILLEGAL_PADDING);
225 /* If positive just copy across */
228 memcpy(b, p + pad, plen - pad);
233 /* check is any following octets are non zero */
234 for (i = 1; i < plen; i++) {
238 /* if all bytes are zero handle as special case */
242 memset(b + 1, 0, plen - 1);
249 /* Must be negative: calculate twos complement */
251 const unsigned char *from = p + plen - 1 + pad;
252 unsigned char *to = b + plen - 1;
254 while (*from == 0 && i) {
259 *to-- = (*from-- ^ 0xff) + 1;
260 OPENSSL_assert(i != 0);
263 *to-- = *from-- ^ 0xff;
268 int i2c_ASN1_INTEGER(ASN1_INTEGER *a, unsigned char **pp)
270 return i2c_ibuf(a->data, a->length, a->type & V_ASN1_NEG, pp);
273 /* Convert big endian buffer into uint64_t, return 0 on error */
274 static int asn1_get_uint64(uint64_t *pr, const unsigned char *b, size_t blen)
277 if (blen > sizeof(*pr)) {
278 ASN1err(ASN1_F_ASN1_GET_UINT64, ASN1_R_TOO_LARGE);
284 for (i = 0; i < blen; i++) {
291 static size_t asn1_put_uint64(unsigned char *b, uint64_t r)
298 /* Work out how many bytes we need */
304 /* Copy from end to beginning */
315 b[0] = (unsigned char)r;
321 * Absolute value of INT64_MIN: we can't just use -INT64_MIN as it produces
325 #define ABS_INT64_MIN \
326 ((uint64_t)INT64_MAX + (uint64_t)(-(INT64_MIN + INT64_MAX)))
328 /* signed version of asn1_get_uint64 */
329 static int asn1_get_int64(int64_t *pr, const unsigned char *b, size_t blen,
333 if (asn1_get_uint64(&r, b, blen) == 0)
336 if (r > ABS_INT64_MIN) {
337 ASN1err(ASN1_F_ASN1_GET_INT64, ASN1_R_TOO_SMALL);
343 ASN1err(ASN1_F_ASN1_GET_INT64, ASN1_R_TOO_LARGE);
351 /* Convert ASN1 INTEGER content octets to ASN1_INTEGER structure */
352 ASN1_INTEGER *c2i_ASN1_INTEGER(ASN1_INTEGER **a, const unsigned char **pp,
355 ASN1_INTEGER *ret = NULL;
359 r = c2i_ibuf(NULL, NULL, *pp, len);
364 if ((a == NULL) || ((*a) == NULL)) {
365 ret = ASN1_INTEGER_new();
368 ret->type = V_ASN1_INTEGER;
372 if (ASN1_STRING_set(ret, NULL, r) == 0)
375 c2i_ibuf(ret->data, &neg, *pp, len);
378 ret->type |= V_ASN1_NEG;
385 ASN1err(ASN1_F_C2I_ASN1_INTEGER, ERR_R_MALLOC_FAILURE);
386 if ((a == NULL) || (*a != ret))
387 ASN1_INTEGER_free(ret);
391 static int asn1_string_get_int64(int64_t *pr, const ASN1_STRING *a, int itype)
394 ASN1err(ASN1_F_ASN1_STRING_GET_INT64, ERR_R_PASSED_NULL_PARAMETER);
397 if ((a->type & ~V_ASN1_NEG) != itype) {
398 ASN1err(ASN1_F_ASN1_STRING_GET_INT64, ASN1_R_WRONG_INTEGER_TYPE);
401 return asn1_get_int64(pr, a->data, a->length, a->type & V_ASN1_NEG);
404 static int asn1_string_set_int64(ASN1_STRING *a, int64_t r, int itype)
406 unsigned char tbuf[sizeof(r)];
410 l = asn1_put_uint64(tbuf, -r);
411 a->type |= V_ASN1_NEG;
413 l = asn1_put_uint64(tbuf, r);
414 a->type &= ~V_ASN1_NEG;
418 return ASN1_STRING_set(a, tbuf, l);
422 * This is a version of d2i_ASN1_INTEGER that ignores the sign bit of ASN1
423 * integers: some broken software can encode a positive INTEGER with its MSB
424 * set as negative (it doesn't add a padding zero).
427 ASN1_INTEGER *d2i_ASN1_UINTEGER(ASN1_INTEGER **a, const unsigned char **pp,
430 ASN1_INTEGER *ret = NULL;
431 const unsigned char *p;
434 int inf, tag, xclass;
437 if ((a == NULL) || ((*a) == NULL)) {
438 if ((ret = ASN1_INTEGER_new()) == NULL)
440 ret->type = V_ASN1_INTEGER;
445 inf = ASN1_get_object(&p, &len, &tag, &xclass, length);
447 i = ASN1_R_BAD_OBJECT_HEADER;
451 if (tag != V_ASN1_INTEGER) {
452 i = ASN1_R_EXPECTING_AN_INTEGER;
457 * We must OPENSSL_malloc stuff, even for 0 bytes otherwise it signifies
458 * a missing NULL parameter.
460 s = OPENSSL_malloc((int)len + 1);
462 i = ERR_R_MALLOC_FAILURE;
465 ret->type = V_ASN1_INTEGER;
467 if ((*p == 0) && (len != 1)) {
471 memcpy(s, p, (int)len);
475 OPENSSL_free(ret->data);
477 ret->length = (int)len;
483 ASN1err(ASN1_F_D2I_ASN1_UINTEGER, i);
484 if ((a == NULL) || (*a != ret))
485 ASN1_INTEGER_free(ret);
489 static ASN1_STRING *bn_to_asn1_string(const BIGNUM *bn, ASN1_STRING *ai,
496 ret = ASN1_STRING_type_new(atype);
503 ASN1err(ASN1_F_BN_TO_ASN1_STRING, ERR_R_NESTED_ASN1_ERROR);
507 if (BN_is_negative(bn) && !BN_is_zero(bn))
508 ret->type |= V_ASN1_NEG_INTEGER;
510 len = BN_num_bytes(bn);
515 if (ASN1_STRING_set(ret, NULL, len) == 0) {
516 ASN1err(ASN1_F_BN_TO_ASN1_STRING, ERR_R_MALLOC_FAILURE);
520 /* Correct zero case */
524 len = BN_bn2bin(bn, ret->data);
529 ASN1_INTEGER_free(ret);
533 static BIGNUM *asn1_string_to_bn(const ASN1_INTEGER *ai, BIGNUM *bn,
538 if ((ai->type & ~V_ASN1_NEG) != itype) {
539 ASN1err(ASN1_F_ASN1_STRING_TO_BN, ASN1_R_WRONG_INTEGER_TYPE);
543 ret = BN_bin2bn(ai->data, ai->length, bn);
545 ASN1err(ASN1_F_ASN1_STRING_TO_BN, ASN1_R_BN_LIB);
548 if (ai->type & V_ASN1_NEG)
549 BN_set_negative(ret, 1);
553 int ASN1_INTEGER_get_int64(int64_t *pr, const ASN1_INTEGER *a)
555 return asn1_string_get_int64(pr, a, V_ASN1_INTEGER);
558 int ASN1_INTEGER_set_int64(ASN1_INTEGER *a, int64_t r)
560 return asn1_string_set_int64(a, r, V_ASN1_INTEGER);
563 int ASN1_INTEGER_set(ASN1_INTEGER *a, long v)
565 return ASN1_INTEGER_set_int64(a, v);
568 long ASN1_INTEGER_get(const ASN1_INTEGER *a)
574 i = ASN1_INTEGER_get_int64(&r, a);
577 if (r > LONG_MAX || r < LONG_MIN)
582 ASN1_INTEGER *BN_to_ASN1_INTEGER(const BIGNUM *bn, ASN1_INTEGER *ai)
584 return bn_to_asn1_string(bn, ai, V_ASN1_INTEGER);
587 BIGNUM *ASN1_INTEGER_to_BN(const ASN1_INTEGER *ai, BIGNUM *bn)
589 return asn1_string_to_bn(ai, bn, V_ASN1_INTEGER);
592 int ASN1_ENUMERATED_get_int64(int64_t *pr, const ASN1_ENUMERATED *a)
594 return asn1_string_get_int64(pr, a, V_ASN1_ENUMERATED);
597 int ASN1_ENUMERATED_set_int64(ASN1_ENUMERATED *a, int64_t r)
599 return asn1_string_set_int64(a, r, V_ASN1_ENUMERATED);
602 int ASN1_ENUMERATED_set(ASN1_ENUMERATED *a, long v)
604 return ASN1_ENUMERATED_set_int64(a, v);
607 long ASN1_ENUMERATED_get(ASN1_ENUMERATED *a)
613 if ((a->type & ~V_ASN1_NEG) != V_ASN1_ENUMERATED)
615 if (a->length > (int)sizeof(long))
617 i = ASN1_ENUMERATED_get_int64(&r, a);
620 if (r > LONG_MAX || r < LONG_MIN)
625 ASN1_ENUMERATED *BN_to_ASN1_ENUMERATED(const BIGNUM *bn, ASN1_ENUMERATED *ai)
627 return bn_to_asn1_string(bn, ai, V_ASN1_ENUMERATED);
630 BIGNUM *ASN1_ENUMERATED_to_BN(const ASN1_ENUMERATED *ai, BIGNUM *bn)
632 return asn1_string_to_bn(ai, bn, V_ASN1_ENUMERATED);