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diff --git a/src/crypto/bn/convert.c b/src/crypto/bn/convert.c
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+/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
+ * All rights reserved.
+ *
+ * This package is an SSL implementation written
+ * by Eric Young (eay@cryptsoft.com).
+ * The implementation was written so as to conform with Netscapes SSL.
+ *
+ * This library is free for commercial and non-commercial use as long as
+ * the following conditions are aheared to. The following conditions
+ * apply to all code found in this distribution, be it the RC4, RSA,
+ * lhash, DES, etc., code; not just the SSL code. The SSL documentation
+ * included with this distribution is covered by the same copyright terms
+ * except that the holder is Tim Hudson (tjh@cryptsoft.com).
+ *
+ * Copyright remains Eric Young's, and as such any Copyright notices in
+ * the code are not to be removed.
+ * If this package is used in a product, Eric Young should be given attribution
+ * as the author of the parts of the library used.
+ * This can be in the form of a textual message at program startup or
+ * in documentation (online or textual) provided with the package.
+ *
+ * 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 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. All advertising materials mentioning features or use of this software
+ * must display the following acknowledgement:
+ * "This product includes cryptographic software written by
+ * Eric Young (eay@cryptsoft.com)"
+ * The word 'cryptographic' can be left out if the rouines from the library
+ * being used are not cryptographic related :-).
+ * 4. If you include any Windows specific code (or a derivative thereof) from
+ * the apps directory (application code) you must include an acknowledgement:
+ * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
+ *
+ * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``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 AUTHOR 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.
+ *
+ * The licence and distribution terms for any publically available version or
+ * derivative of this code cannot be changed. i.e. this code cannot simply be
+ * copied and put under another distribution licence
+ * [including the GNU Public Licence.] */
+
+#include <openssl/bn.h>
+
+#include <ctype.h>
+#include <stdio.h>
+#include <string.h>
+
+#include <openssl/bio.h>
+#include <openssl/err.h>
+#include <openssl/mem.h>
+
+#include "internal.h"
+
+BIGNUM *BN_bin2bn(const uint8_t *in, size_t len, BIGNUM *ret) {
+ unsigned num_words, m;
+ BN_ULONG word = 0;
+ BIGNUM *bn = NULL;
+
+ if (ret == NULL) {
+ ret = bn = BN_new();
+ }
+
+ if (ret == NULL) {
+ return NULL;
+ }
+
+ if (len == 0) {
+ ret->top = 0;
+ return ret;
+ }
+
+ num_words = ((len - 1) / BN_BYTES) + 1;
+ m = (len - 1) % BN_BYTES;
+ if (bn_wexpand(ret, num_words) == NULL) {
+ if (bn) {
+ BN_free(bn);
+ }
+ return NULL;
+ }
+
+ ret->top = num_words;
+ ret->neg = 0;
+
+ while (len--) {
+ word = (word << 8) | *(in++);
+ if (m-- == 0) {
+ ret->d[--num_words] = word;
+ word = 0;
+ m = BN_BYTES - 1;
+ }
+ }
+
+ /* need to call this due to clear byte at top if avoiding having the top bit
+ * set (-ve number) */
+ bn_correct_top(ret);
+ return ret;
+}
+
+size_t BN_bn2bin(const BIGNUM *in, uint8_t *out) {
+ size_t n, i;
+ BN_ULONG l;
+
+ n = i = BN_num_bytes(in);
+ while (i--) {
+ l = in->d[i / BN_BYTES];
+ *(out++) = (unsigned char)(l >> (8 * (i % BN_BYTES))) & 0xff;
+ }
+ return n;
+}
+
+/* constant_time_select_ulong returns |x| if |v| is 1 and |y| if |v| is 0. Its
+ * behavior is undefined if |v| takes any other value. */
+static BN_ULONG constant_time_select_ulong(int v, BN_ULONG x, BN_ULONG y) {
+ BN_ULONG mask = v;
+ mask--;
+
+ return (~mask & x) | (mask & y);
+}
+
+/* constant_time_le_size_t returns 1 if |x| <= |y| and 0 otherwise. |x| and |y|
+ * must not have their MSBs set. */
+static int constant_time_le_size_t(size_t x, size_t y) {
+ return ((x - y - 1) >> (sizeof(size_t) * 8 - 1)) & 1;
+}
+
+/* read_word_padded returns the |i|'th word of |in|, if it is not out of
+ * bounds. Otherwise, it returns 0. It does so without branches on the size of
+ * |in|, however it necessarily does not have the same memory access pattern. If
+ * the access would be out of bounds, it reads the last word of |in|. |in| must
+ * not be zero. */
+static BN_ULONG read_word_padded(const BIGNUM *in, size_t i) {
+ /* Read |in->d[i]| if valid. Otherwise, read the last word. */
+ BN_ULONG l = in->d[constant_time_select_ulong(
+ constant_time_le_size_t(in->dmax, i), in->dmax - 1, i)];
+
+ /* Clamp to zero if above |d->top|. */
+ return constant_time_select_ulong(constant_time_le_size_t(in->top, i), 0, l);
+}
+
+int BN_bn2bin_padded(uint8_t *out, size_t len, const BIGNUM *in) {
+ size_t i;
+ BN_ULONG l;
+
+ /* Special case for |in| = 0. Just branch as the probability is negligible. */
+ if (BN_is_zero(in)) {
+ memset(out, 0, len);
+ return 1;
+ }
+
+ /* Check if the integer is too big. This case can exit early in non-constant
+ * time. */
+ if ((size_t)in->top > (len + (BN_BYTES - 1)) / BN_BYTES) {
+ return 0;
+ }
+ if ((len % BN_BYTES) != 0) {
+ l = read_word_padded(in, len / BN_BYTES);
+ if (l >> (8 * (len % BN_BYTES)) != 0) {
+ return 0;
+ }
+ }
+
+ /* Write the bytes out one by one. Serialization is done without branching on
+ * the bits of |in| or on |in->top|, but if the routine would otherwise read
+ * out of bounds, the memory access pattern can't be fixed. However, for an
+ * RSA key of size a multiple of the word size, the probability of BN_BYTES
+ * leading zero octets is low.
+ *
+ * See Falko Stenzke, "Manger's Attack revisited", ICICS 2010. */
+ i = len;
+ while (i--) {
+ l = read_word_padded(in, i / BN_BYTES);
+ *(out++) = (uint8_t)(l >> (8 * (i % BN_BYTES))) & 0xff;
+ }
+ return 1;
+}
+
+static const char hextable[] = "0123456789abcdef";
+
+char *BN_bn2hex(const BIGNUM *bn) {
+ int i, j, v, z = 0;
+ char *buf;
+ char *p;
+
+ buf = (char *)OPENSSL_malloc(bn->top * BN_BYTES * 2 + 2);
+ if (buf == NULL) {
+ OPENSSL_PUT_ERROR(BN, BN_bn2hex, ERR_R_MALLOC_FAILURE);
+ return NULL;
+ }
+
+ p = buf;
+ if (bn->neg) {
+ *(p++) = '-';
+ }
+
+ if (BN_is_zero(bn)) {
+ *(p++) = '0';
+ }
+
+ for (i = bn->top - 1; i >= 0; i--) {
+ for (j = BN_BITS2 - 8; j >= 0; j -= 8) {
+ /* strip leading zeros */
+ v = ((int)(bn->d[i] >> (long)j)) & 0xff;
+ if (z || v != 0) {
+ *(p++) = hextable[v >> 4];
+ *(p++) = hextable[v & 0x0f];
+ z = 1;
+ }
+ }
+ }
+ *p = '\0';
+
+ return buf;
+}
+
+/* decode_hex decodes |i| bytes of hex data from |in| and updates |bn|. */
+static void decode_hex(BIGNUM *bn, const char *in, int i) {
+ int h, m, j, k, c;
+ BN_ULONG l=0;
+
+ j = i; /* least significant 'hex' */
+ h = 0;
+ while (j > 0) {
+ m = ((BN_BYTES * 2) <= j) ? (BN_BYTES * 2) : j;
+ l = 0;
+ for (;;) {
+ c = in[j - m];
+ if ((c >= '0') && (c <= '9')) {
+ k = c - '0';
+ } else if ((c >= 'a') && (c <= 'f')) {
+ k = c - 'a' + 10;
+ } else if ((c >= 'A') && (c <= 'F')) {
+ k = c - 'A' + 10;
+ } else {
+ k = 0; /* paranoia */
+ }
+
+ l = (l << 4) | k;
+
+ if (--m <= 0) {
+ bn->d[h++] = l;
+ break;
+ }
+ }
+
+ j -= (BN_BYTES * 2);
+ }
+
+ bn->top = h;
+}
+
+/* decode_dec decodes |i| bytes of decimal data from |in| and updates |bn|. */
+static void decode_dec(BIGNUM *bn, const char *in, int i) {
+ int j;
+ BN_ULONG l = 0;
+
+ j = BN_DEC_NUM - (i % BN_DEC_NUM);
+ if (j == BN_DEC_NUM) {
+ j = 0;
+ }
+ l = 0;
+ while (*in) {
+ l *= 10;
+ l += *in - '0';
+ in++;
+ if (++j == BN_DEC_NUM) {
+ BN_mul_word(bn, BN_DEC_CONV);
+ BN_add_word(bn, l);
+ l = 0;
+ j = 0;
+ }
+ }
+}
+
+typedef void (*decode_func) (BIGNUM *bn, const char *in, int i);
+typedef int (*char_test_func) (int c);
+
+static int bn_x2bn(BIGNUM **outp, const char *in, decode_func decode, char_test_func want_char) {
+ BIGNUM *ret = NULL;
+ int neg = 0, i;
+ int num;
+
+ if (in == NULL || *in == 0) {
+ return 0;
+ }
+
+ if (*in == '-') {
+ neg = 1;
+ in++;
+ }
+
+ for (i = 0; want_char((unsigned char)in[i]); i++) {}
+
+ num = i + neg;
+ if (outp == NULL) {
+ return num;
+ }
+
+ /* in is the start of the hex digits, and it is 'i' long */
+ if (*outp == NULL) {
+ ret = BN_new();
+ if (ret == NULL) {
+ return 0;
+ }
+ } else {
+ ret = *outp;
+ BN_zero(ret);
+ }
+ ret->neg = neg;
+
+ /* i is the number of hex digests; */
+ if (bn_expand(ret, i * 4) == NULL) {
+ goto err;
+ }
+
+ decode(ret, in, i);
+
+ bn_correct_top(ret);
+
+ *outp = ret;
+ return num;
+
+err:
+ if (*outp == NULL) {
+ BN_free(ret);
+ }
+
+ return 0;
+}
+
+int BN_hex2bn(BIGNUM **outp, const char *in) {
+ return bn_x2bn(outp, in, decode_hex, isxdigit);
+}
+
+char *BN_bn2dec(const BIGNUM *a) {
+ int i = 0, num, ok = 0;
+ char *buf = NULL;
+ char *p;
+ BIGNUM *t = NULL;
+ BN_ULONG *bn_data = NULL, *lp;
+
+ /* get an upper bound for the length of the decimal integer
+ * num <= (BN_num_bits(a) + 1) * log(2)
+ * <= 3 * BN_num_bits(a) * 0.1001 + log(2) + 1 (rounding error)
+ * <= BN_num_bits(a)/10 + BN_num_bits/1000 + 1 + 1
+ */
+ i = BN_num_bits(a) * 3;
+ num = i / 10 + i / 1000 + 1 + 1;
+ bn_data =
+ (BN_ULONG *)OPENSSL_malloc((num / BN_DEC_NUM + 1) * sizeof(BN_ULONG));
+ buf = (char *)OPENSSL_malloc(num + 3);
+ if ((buf == NULL) || (bn_data == NULL)) {
+ OPENSSL_PUT_ERROR(BN, BN_bn2dec, ERR_R_MALLOC_FAILURE);
+ goto err;
+ }
+ t = BN_dup(a);
+ if (t == NULL) {
+ goto err;
+ }
+
+#define BUF_REMAIN (num + 3 - (size_t)(p - buf))
+ p = buf;
+ lp = bn_data;
+ if (BN_is_zero(t)) {
+ *(p++) = '0';
+ *(p++) = '\0';
+ } else {
+ if (BN_is_negative(t)) {
+ *p++ = '-';
+ }
+
+ while (!BN_is_zero(t)) {
+ *lp = BN_div_word(t, BN_DEC_CONV);
+ lp++;
+ }
+ lp--;
+ /* We now have a series of blocks, BN_DEC_NUM chars
+ * in length, where the last one needs truncation.
+ * The blocks need to be reversed in order. */
+ BIO_snprintf(p, BUF_REMAIN, BN_DEC_FMT1, *lp);
+ while (*p) {
+ p++;
+ }
+ while (lp != bn_data) {
+ lp--;
+ BIO_snprintf(p, BUF_REMAIN, BN_DEC_FMT2, *lp);
+ while (*p) {
+ p++;
+ }
+ }
+ }
+ ok = 1;
+
+err:
+ if (bn_data != NULL) {
+ OPENSSL_free(bn_data);
+ }
+ if (t != NULL) {
+ BN_free(t);
+ }
+ if (!ok && buf) {
+ OPENSSL_free(buf);
+ buf = NULL;
+ }
+
+ return buf;
+}
+
+int BN_dec2bn(BIGNUM **outp, const char *in) {
+ return bn_x2bn(outp, in, decode_dec, isdigit);
+}
+
+int BN_asc2bn(BIGNUM **outp, const char *in) {
+ const char *const orig_in = in;
+ if (*in == '-') {
+ in++;
+ }
+
+ if (in[0] == '0' && (in[1] == 'X' || in[1] == 'x')) {
+ if (!BN_hex2bn(outp, in+2)) {
+ return 0;
+ }
+ } else {
+ if (!BN_dec2bn(outp, in)) {
+ return 0;
+ }
+ }
+
+ if (*orig_in == '-') {
+ (*outp)->neg = 1;
+ }
+
+ return 1;
+}
+
+int BN_print(BIO *bp, const BIGNUM *a) {
+ int i, j, v, z = 0;
+ int ret = 0;
+
+ if (a->neg && BIO_write(bp, "-", 1) != 1) {
+ goto end;
+ }
+
+ if (BN_is_zero(a) && BIO_write(bp, "0", 1) != 1) {
+ goto end;
+ }
+
+ for (i = a->top - 1; i >= 0; i--) {
+ for (j = BN_BITS2 - 4; j >= 0; j -= 4) {
+ /* strip leading zeros */
+ v = ((int)(a->d[i] >> (long)j)) & 0x0f;
+ if (z || v != 0) {
+ if (BIO_write(bp, &hextable[v], 1) != 1) {
+ goto end;
+ }
+ z = 1;
+ }
+ }
+ }
+ ret = 1;
+
+end:
+ return ret;
+}
+
+int BN_print_fp(FILE *fp, const BIGNUM *a) {
+ BIO *b;
+ int ret;
+
+ b = BIO_new(BIO_s_file());
+ if (b == NULL) {
+ return 0;
+ }
+ BIO_set_fp(b, fp, BIO_NOCLOSE);
+ ret = BN_print(b, a);
+ BIO_free(b);
+
+ return ret;
+}
+
+BN_ULONG BN_get_word(const BIGNUM *bn) {
+ switch (bn->top) {
+ case 0:
+ return 0;
+ case 1:
+ return bn->d[0];
+ default:
+ return BN_MASK2;
+ }
+}
generated by cgit v1.1 at 2024-05-23 03:09:45 +0000