diff options
Diffstat (limited to 'third_party/heimdal/lib/hcrypto/bn.c')
-rw-r--r-- | third_party/heimdal/lib/hcrypto/bn.c | 529 |
1 files changed, 529 insertions, 0 deletions
diff --git a/third_party/heimdal/lib/hcrypto/bn.c b/third_party/heimdal/lib/hcrypto/bn.c new file mode 100644 index 0000000..62297b1 --- /dev/null +++ b/third_party/heimdal/lib/hcrypto/bn.c @@ -0,0 +1,529 @@ +/* + * Copyright (c) 2006 Kungliga Tekniska Högskolan + * (Royal Institute of Technology, Stockholm, Sweden). + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * 3. Neither the name of the Institute nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#include <config.h> +#include <roken.h> + +#include <krb5-types.h> +#include <rfc2459_asn1.h> /* XXX */ +#include <der.h> + +#include <bn.h> +#include <rand.h> +#include <hex.h> + +BIGNUM * +BN_new(void) +{ + heim_integer *hi; + hi = calloc(1, sizeof(*hi)); + return (BIGNUM *)hi; +} + +void +BN_free(BIGNUM *bn) +{ + BN_clear(bn); + free(bn); +} + +void +BN_clear(BIGNUM *bn) +{ + heim_integer *hi = (heim_integer *)bn; + if (hi->data) { + memset(hi->data, 0, hi->length); + free(hi->data); + } + memset(hi, 0, sizeof(*hi)); +} + +void +BN_clear_free(BIGNUM *bn) +{ + BN_free(bn); +} + +BIGNUM * +BN_dup(const BIGNUM *bn) +{ + BIGNUM *b = BN_new(); + if (der_copy_heim_integer((const heim_integer *)bn, (heim_integer *)b)) { + BN_free(b); + return NULL; + } + return b; +} + +/* + * If the caller really want to know the number of bits used, subtract + * one from the length, multiply by 8, and then lookup in the table + * how many bits the hightest byte uses. + */ +int +BN_num_bits(const BIGNUM *bn) +{ + static unsigned char num2bits[256] = { + 0,1,2,2,3,3,3,3,4,4,4,4,4,4,4,4, 5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5, + 6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6, 6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6, + 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7, 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7, + 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7, 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7, + 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8, 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8, + 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8, 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8, + 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8, 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8, + 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8, 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8, + }; + const heim_integer *i = (const void *)bn; + if (i->length == 0) + return 0; + return (i->length - 1) * 8 + num2bits[((unsigned char *)i->data)[0]]; +} + +int +BN_num_bytes(const BIGNUM *bn) +{ + return ((const heim_integer *)bn)->length; +} + +/* + * Ignore negative flag. + */ + +BIGNUM * +BN_bin2bn(const void *s, int len, BIGNUM *bn) +{ + heim_integer *hi = (void *)bn; + + if (len < 0) + return NULL; + + if (hi == NULL) { + hi = (heim_integer *)BN_new(); + if (hi == NULL) + return NULL; + } + if (hi->data) + BN_clear((BIGNUM *)hi); + hi->negative = 0; + hi->data = malloc(len); + if (hi->data == NULL && len != 0) { + if (bn == NULL) + BN_free((BIGNUM *)hi); + return NULL; + } + hi->length = len; + if (len) + memcpy(hi->data, s, len); + return (BIGNUM *)hi; +} + +int +BN_bn2bin(const BIGNUM *bn, void *to) +{ + const heim_integer *hi = (const void *)bn; + memcpy(to, hi->data, hi->length); + return hi->length; +} + +int +BN_hex2bn(BIGNUM **bnp, const char *in) +{ + int negative; + ssize_t ret; + size_t len; + void *data; + + len = strlen(in); + data = malloc(len); + if (data == NULL) + return 0; + + if (*in == '-') { + negative = 1; + in++; + } else + negative = 0; + + ret = hex_decode(in, data, len); + if (ret < 0) { + free(data); + return 0; + } + + *bnp = BN_bin2bn(data, ret, NULL); + free(data); + if (*bnp == NULL) + return 0; + BN_set_negative(*bnp, negative); + return 1; +} + +char * +BN_bn2hex(const BIGNUM *bn) +{ + ssize_t ret; + size_t len; + void *data; + char *str; + + len = BN_num_bytes(bn); + data = malloc(len); + if (data == NULL) + return 0; + + len = BN_bn2bin(bn, data); + + ret = hex_encode(data, len, &str); + free(data); + if (ret < 0) + return 0; + + return str; +} + +int +BN_cmp(const BIGNUM *bn1, const BIGNUM *bn2) +{ + return der_heim_integer_cmp((const heim_integer *)bn1, + (const heim_integer *)bn2); +} + +void +BN_set_negative(BIGNUM *bn, int flag) +{ + ((heim_integer *)bn)->negative = (flag ? 1 : 0); +} + +int +BN_is_negative(const BIGNUM *bn) +{ + return ((const heim_integer *)bn)->negative ? 1 : 0; +} + +static const unsigned char is_set[8] = { 1, 2, 4, 8, 16, 32, 64, 128 }; + +int +BN_is_bit_set(const BIGNUM *bn, int bit) +{ + heim_integer *hi = (heim_integer *)bn; + unsigned char *p = hi->data; + + if ((bit / 8) >= hi->length || hi->length == 0) + return 0; + + return p[hi->length - 1 - (bit / 8)] & is_set[bit % 8]; +} + +int +BN_set_bit(BIGNUM *bn, int bit) +{ + heim_integer *hi = (heim_integer *)bn; + unsigned char *p; + + if ((bit / 8) > hi->length || hi->length == 0) { + size_t len = bit == 0 ? 1 : (bit + 7) / 8; + void *d = realloc(hi->data, len); + if (d == NULL) + return 0; + hi->data = d; + p = hi->data; + memset(&p[hi->length], 0, len); + hi->length = len; + } else + p = hi->data; + + p[hi->length - 1 - (bit / 8)] |= is_set[bit % 8]; + return 1; +} + +int +BN_clear_bit(BIGNUM *bn, int bit) +{ + heim_integer *hi = (heim_integer *)bn; + unsigned char *p = hi->data; + + if ((bit / 8) > hi->length || hi->length == 0) + return 0; + + p[hi->length - 1 - (bit / 8)] &= (unsigned char)(~(is_set[bit % 8])); + + return 1; +} + +int +BN_set_word(BIGNUM *bn, unsigned long num) +{ + unsigned char p[sizeof(num)]; + unsigned long num2; + int i, len; + + if (bn == NULL) + return 0; + + for (num2 = num, i = 0; num2 > 0; i++) + num2 = num2 >> 8; + + len = i; + for (; i > 0; i--) { + p[i - 1] = (num & 0xff); + num = num >> 8; + } + + bn = BN_bin2bn(p, len, bn); + return bn != NULL; +} + +unsigned long +BN_get_word(const BIGNUM *bn) +{ + heim_integer *hi = (heim_integer *)bn; + unsigned long num = 0; + int i; + + if (hi->negative || hi->length > sizeof(num)) + return ULONG_MAX; + + for (i = 0; i < hi->length; i++) + num = ((unsigned char *)hi->data)[i] | (num << 8); + return num; +} + +int +BN_rand(BIGNUM *bn, int bits, int top, int bottom) +{ + size_t len = (bits + 7) / 8; + heim_integer *i = (heim_integer *)bn; + + BN_clear(bn); + + i->negative = 0; + i->data = malloc(len); + if (i->data == NULL && len != 0) + return 0; + i->length = len; + + if (RAND_bytes(i->data, i->length) != 1) { + free(i->data); + i->data = NULL; + return 0; + } + + { + size_t j = len * 8; + while(j > bits) { + BN_clear_bit(bn, j - 1); + j--; + } + } + + if (top == -1) { + ; + } else if (top == 0 && bits > 0) { + BN_set_bit(bn, bits - 1); + } else if (top == 1 && bits > 1) { + BN_set_bit(bn, bits - 1); + BN_set_bit(bn, bits - 2); + } else { + BN_clear(bn); + return 0; + } + + if (bottom && bits > 0) + BN_set_bit(bn, 0); + + return 1; +} + +/* + * + */ + +int +BN_uadd(BIGNUM *res, const BIGNUM *a, const BIGNUM *b) +{ + const heim_integer *ai = (const heim_integer *)a; + const heim_integer *bi = (const heim_integer *)b; + const unsigned char *ap, *bp; + unsigned char *cp; + heim_integer ci; + int carry = 0; + ssize_t len; + + if (ai->negative && bi->negative) + return 0; + if (ai->length < bi->length) { + const heim_integer *si = bi; + bi = ai; ai = si; + } + + ci.negative = 0; + ci.length = ai->length + 1; + ci.data = malloc(ci.length); + if (ci.data == NULL) + return 0; + + ap = &((const unsigned char *)ai->data)[ai->length - 1]; + bp = &((const unsigned char *)bi->data)[bi->length - 1]; + cp = &((unsigned char *)ci.data)[ci.length - 1]; + + for (len = bi->length; len > 0; len--) { + carry = *ap + *bp + carry; + *cp = carry & 0xff; + carry = (carry & ~0xff) ? 1 : 0; + ap--; bp--; cp--; + } + for (len = ai->length - bi->length; len > 0; len--) { + carry = *ap + carry; + *cp = carry & 0xff; + carry = (carry & ~0xff) ? 1 : 0; + ap--; cp--; + } + if (!carry) + memmove(cp, cp + 1, --ci.length); + else + *cp = carry; + + BN_clear(res); + *((heim_integer *)res) = ci; + + return 1; +} + + +/* + * Callback when doing slow generation of numbers, like primes. + */ + +void +BN_GENCB_set(BN_GENCB *gencb, int (*cb_2)(int, int, BN_GENCB *), void *ctx) +{ + gencb->ver = 2; + gencb->cb.cb_2 = cb_2; + gencb->arg = ctx; +} + +int +BN_GENCB_call(BN_GENCB *cb, int a, int b) +{ + if (cb == NULL || cb->cb.cb_2 == NULL) + return 1; + return cb->cb.cb_2(a, b, cb); +} + +/* + * + */ + +struct BN_CTX { + struct { + BIGNUM **val; + size_t used; + size_t len; + } bn; + struct { + size_t *val; + size_t used; + size_t len; + } stack; +}; + +BN_CTX * +BN_CTX_new(void) +{ + struct BN_CTX *c; + c = calloc(1, sizeof(*c)); + return c; +} + +void +BN_CTX_free(BN_CTX *c) +{ + size_t i; + for (i = 0; i < c->bn.len; i++) + BN_free(c->bn.val[i]); + free(c->bn.val); + free(c->stack.val); +} + +BIGNUM * +BN_CTX_get(BN_CTX *c) +{ + if (c->bn.used == c->bn.len) { + void *ptr; + size_t i; + c->bn.len += 16; + ptr = realloc(c->bn.val, c->bn.len * sizeof(c->bn.val[0])); + if (ptr == NULL) + return NULL; + c->bn.val = ptr; + for (i = c->bn.used; i < c->bn.len; i++) { + c->bn.val[i] = BN_new(); + if (c->bn.val[i] == NULL) { + c->bn.len = i; + return NULL; + } + } + } + return c->bn.val[c->bn.used++]; +} + +void +BN_CTX_start(BN_CTX *c) +{ + if (c->stack.used == c->stack.len) { + void *ptr; + c->stack.len += 16; + ptr = realloc(c->stack.val, c->stack.len * sizeof(c->stack.val[0])); + if (ptr == NULL) + abort(); + c->stack.val = ptr; + } + c->stack.val[c->stack.used++] = c->bn.used; +} + +void +BN_CTX_end(BN_CTX *c) +{ + const size_t prev = c->stack.val[c->stack.used - 1]; + size_t i; + + if (c->stack.used == 0) + abort(); + + for (i = prev; i < c->bn.used; i++) + BN_clear(c->bn.val[i]); + + c->stack.used--; + c->bn.used = prev; +} + |