X-Git-Url: https://git.openssl.org/?p=openssl.git;a=blobdiff_plain;f=crypto%2Fbn%2Fbn_lib.c;h=7c434020de7c1b50feb2f5717aebe26a8e688bad;hp=c742db6f1f7c277f6a4cc2625b06301d9c051db4;hb=4f22f40507fea3f272637eb8e00cadf1f34b10d9;hpb=0f113f3ee4d629ef9a4a30911b22b224772085e5 diff --git a/crypto/bn/bn_lib.c b/crypto/bn/bn_lib.c index c742db6f1f..7c434020de 100644 --- a/crypto/bn/bn_lib.c +++ b/crypto/bn/bn_lib.c @@ -1,75 +1,20 @@ -/* crypto/bn/bn_lib.c */ -/* 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. +/* + * Copyright 1995-2016 The OpenSSL Project Authors. All Rights Reserved. * - * 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.] + * Licensed under the OpenSSL license (the "License"). You may not use + * this file except in compliance with the License. You can obtain a copy + * in the file LICENSE in the source distribution or at + * https://www.openssl.org/source/license.html */ -#ifndef BN_DEBUG -# undef NDEBUG /* avoid conflicting definitions */ -# define NDEBUG -#endif - #include #include -#include "cryptlib.h" +#include "internal/cryptlib.h" #include "bn_lcl.h" - -const char BN_version[] = "Big Number" OPENSSL_VERSION_PTEXT; +#include /* This stuff appears to be completely unused, so is deprecated */ -#ifndef OPENSSL_NO_DEPRECATED +#if OPENSSL_API_COMPAT < 0x00908000L /*- * For a 32 bit machine * 2 - 4 == 128 @@ -223,6 +168,15 @@ int BN_num_bits(const BIGNUM *a) return ((i * BN_BITS2) + BN_num_bits_word(a->d[i])); } +static void bn_free_d(BIGNUM *a) +{ + if (BN_get_flags(a,BN_FLG_SECURE)) + OPENSSL_secure_free(a->d); + else + OPENSSL_free(a->d); +} + + void BN_clear_free(BIGNUM *a) { int i; @@ -232,11 +186,11 @@ void BN_clear_free(BIGNUM *a) bn_check_top(a); if (a->d != NULL) { OPENSSL_cleanse(a->d, a->dmax * sizeof(a->d[0])); - if (!(BN_get_flags(a, BN_FLG_STATIC_DATA))) - OPENSSL_free(a->d); + if (!BN_get_flags(a, BN_FLG_STATIC_DATA)) + bn_free_d(a); } i = BN_get_flags(a, BN_FLG_MALLOCED); - OPENSSL_cleanse(a, sizeof(BIGNUM)); + OPENSSL_cleanse(a, sizeof(*a)); if (i) OPENSSL_free(a); } @@ -246,21 +200,23 @@ void BN_free(BIGNUM *a) if (a == NULL) return; bn_check_top(a); - if ((a->d != NULL) && !(BN_get_flags(a, BN_FLG_STATIC_DATA))) - OPENSSL_free(a->d); + if (!BN_get_flags(a, BN_FLG_STATIC_DATA)) + bn_free_d(a); if (a->flags & BN_FLG_MALLOCED) OPENSSL_free(a); else { -#ifndef OPENSSL_NO_DEPRECATED +#if OPENSSL_API_COMPAT < 0x00908000L a->flags |= BN_FLG_FREE; #endif a->d = NULL; } } -void BN_init(BIGNUM *a) +void bn_init(BIGNUM *a) { - memset(a, 0, sizeof(BIGNUM)); + static BIGNUM nilbn; + + *a = nilbn; bn_check_top(a); } @@ -268,20 +224,24 @@ BIGNUM *BN_new(void) { BIGNUM *ret; - if ((ret = (BIGNUM *)OPENSSL_malloc(sizeof(BIGNUM))) == NULL) { + if ((ret = OPENSSL_zalloc(sizeof(*ret))) == NULL) { BNerr(BN_F_BN_NEW, ERR_R_MALLOC_FAILURE); return (NULL); } ret->flags = BN_FLG_MALLOCED; - ret->top = 0; - ret->neg = 0; - ret->dmax = 0; - ret->d = NULL; bn_check_top(ret); return (ret); } -/* This is used both by bn_expand2() and bn_dup_expand() */ + BIGNUM *BN_secure_new(void) + { + BIGNUM *ret = BN_new(); + if (ret != NULL) + ret->flags |= BN_FLG_SECURE; + return (ret); + } + +/* This is used by bn_expand2() */ /* The caller MUST check that words > b->dmax before calling this */ static BN_ULONG *bn_expand_internal(const BIGNUM *b, int words) { @@ -299,20 +259,14 @@ static BN_ULONG *bn_expand_internal(const BIGNUM *b, int words) BNerr(BN_F_BN_EXPAND_INTERNAL, BN_R_EXPAND_ON_STATIC_BIGNUM_DATA); return (NULL); } - a = A = (BN_ULONG *)OPENSSL_malloc(sizeof(BN_ULONG) * words); + if (BN_get_flags(b,BN_FLG_SECURE)) + a = A = OPENSSL_secure_zalloc(words * sizeof(*a)); + else + a = A = OPENSSL_zalloc(words * sizeof(*a)); if (A == NULL) { BNerr(BN_F_BN_EXPAND_INTERNAL, ERR_R_MALLOC_FAILURE); return (NULL); } -#ifdef PURIFY - /* - * Valgrind complains in BN_consttime_swap because we process the whole - * array even if it's not initialised yet. This doesn't matter in that - * function - what's important is constant time operation (we're not - * actually going to use the data) - */ - memset(a, 0, sizeof(BN_ULONG) * words); -#endif #if 1 B = b->d; @@ -323,7 +277,7 @@ static BN_ULONG *bn_expand_internal(const BIGNUM *b, int words) * The fact that the loop is unrolled * 4-wise is a tribute to Intel. It's * the one that doesn't have enough - * registers to accomodate more data. + * registers to accommodate more data. * I'd unroll it 8-wise otherwise:-) * * @@ -338,11 +292,6 @@ static BN_ULONG *bn_expand_internal(const BIGNUM *b, int words) A[2] = a2; A[3] = a3; } - /* - * workaround for ultrix cc: without 'case 0', the optimizer does - * the switch table by doing a=top&3; a--; goto jump_table[a]; - * which fails for top== 0 - */ switch (b->top & 3) { case 3: A[2] = B[2]; @@ -351,11 +300,12 @@ static BN_ULONG *bn_expand_internal(const BIGNUM *b, int words) case 1: A[0] = B[0]; case 0: + /* Without the "case 0" some old optimizers got this wrong. */ ; } } #else - memset(A, 0, sizeof(BN_ULONG) * words); + memset(A, 0, sizeof(*A) * words); memcpy(A, b->d, sizeof(b->d[0]) * b->top); #endif @@ -378,35 +328,14 @@ BIGNUM *bn_expand2(BIGNUM *b, int words) BN_ULONG *a = bn_expand_internal(b, words); if (!a) return NULL; - if (b->d) - OPENSSL_free(b->d); + if (b->d) { + OPENSSL_cleanse(b->d, b->dmax * sizeof(b->d[0])); + bn_free_d(b); + } b->d = a; b->dmax = words; } -/* None of this should be necessary because of what b->top means! */ -#if 0 - /* - * NB: bn_wexpand() calls this only if the BIGNUM really has to grow - */ - if (b->top < b->dmax) { - int i; - BN_ULONG *A = &(b->d[b->top]); - for (i = (b->dmax - b->top) >> 3; i > 0; i--, A += 8) { - A[0] = 0; - A[1] = 0; - A[2] = 0; - A[3] = 0; - A[4] = 0; - A[5] = 0; - A[6] = 0; - A[7] = 0; - } - for (i = (b->dmax - b->top) & 7; i > 0; i--, A++) - A[0] = 0; - assert(A == &(b->d[b->dmax])); - } -#endif bn_check_top(b); return b; } @@ -419,7 +348,7 @@ BIGNUM *BN_dup(const BIGNUM *a) return NULL; bn_check_top(a); - t = BN_new(); + t = BN_get_flags(a, BN_FLG_SECURE) ? BN_secure_new() : BN_new(); if (t == NULL) return NULL; if (!BN_copy(t, a)) { @@ -516,7 +445,7 @@ void BN_clear(BIGNUM *a) { bn_check_top(a); if (a->d != NULL) - memset(a->d, 0, a->dmax * sizeof(a->d[0])); + memset(a->d, 0, sizeof(*a->d) * a->dmax); a->top = 0; a->neg = 0; } @@ -555,7 +484,9 @@ BIGNUM *BN_bin2bn(const unsigned char *s, int len, BIGNUM *ret) if (ret == NULL) return (NULL); bn_check_top(ret); - l = 0; + /* Skip leading zero's. */ + for ( ; len > 0 && *s == 0; s++, len--) + continue; n = len; if (n == 0) { ret->top = 0; @@ -564,12 +495,12 @@ BIGNUM *BN_bin2bn(const unsigned char *s, int len, BIGNUM *ret) i = ((n - 1) / BN_BYTES) + 1; m = ((n - 1) % (BN_BYTES)); if (bn_wexpand(ret, (int)i) == NULL) { - if (bn) - BN_free(bn); + BN_free(bn); return NULL; } ret->top = i; ret->neg = 0; + l = 0; while (n--) { l = (l << 8L) | *(s++); if (m-- == 0) { @@ -587,18 +518,104 @@ BIGNUM *BN_bin2bn(const unsigned char *s, int len, BIGNUM *ret) } /* ignore negative */ -int BN_bn2bin(const BIGNUM *a, unsigned char *to) +static int bn2binpad(const BIGNUM *a, unsigned char *to, int tolen) { - int n, i; + int i; BN_ULONG l; bn_check_top(a); - n = i = BN_num_bytes(a); + i = BN_num_bytes(a); + if (tolen == -1) + tolen = i; + else if (tolen < i) + return -1; + /* Add leading zeroes if necessary */ + if (tolen > i) { + memset(to, 0, tolen - i); + to += tolen - i; + } while (i--) { l = a->d[i / BN_BYTES]; *(to++) = (unsigned char)(l >> (8 * (i % BN_BYTES))) & 0xff; } - return (n); + return tolen; +} + +int BN_bn2binpad(const BIGNUM *a, unsigned char *to, int tolen) +{ + if (tolen < 0) + return -1; + return bn2binpad(a, to, tolen); +} + +int BN_bn2bin(const BIGNUM *a, unsigned char *to) +{ + return bn2binpad(a, to, -1); +} + +BIGNUM *BN_lebin2bn(const unsigned char *s, int len, BIGNUM *ret) +{ + unsigned int i, m; + unsigned int n; + BN_ULONG l; + BIGNUM *bn = NULL; + + if (ret == NULL) + ret = bn = BN_new(); + if (ret == NULL) + return (NULL); + bn_check_top(ret); + s += len - 1; + /* Skip trailing zeroes. */ + for ( ; len > 0 && *s == 0; s--, len--) + continue; + n = len; + if (n == 0) { + ret->top = 0; + return ret; + } + i = ((n - 1) / BN_BYTES) + 1; + m = ((n - 1) % (BN_BYTES)); + if (bn_wexpand(ret, (int)i) == NULL) { + BN_free(bn); + return NULL; + } + ret->top = i; + ret->neg = 0; + l = 0; + while (n--) { + l = (l << 8L) | *(s--); + if (m-- == 0) { + ret->d[--i] = l; + l = 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; +} + +int BN_bn2lebinpad(const BIGNUM *a, unsigned char *to, int tolen) +{ + int i; + BN_ULONG l; + bn_check_top(a); + i = BN_num_bytes(a); + if (tolen < i) + return -1; + /* Add trailing zeroes if necessary */ + if (tolen > i) + memset(to + i, 0, tolen - i); + to += i - 1; + while (i--) { + l = a->d[i / BN_BYTES]; + *(to--) = (unsigned char)(l >> (8 * (i % BN_BYTES))) & 0xff; + } + return tolen; } int BN_ucmp(const BIGNUM *a, const BIGNUM *b) @@ -774,9 +791,9 @@ int bn_cmp_words(const BN_ULONG *a, const BN_ULONG *b, int n) /* * Here follows a specialised variants of bn_cmp_words(). It has the - * property of performing the operation on arrays of different sizes. The + * capability of performing the operation on arrays of different sizes. The * sizes of those arrays is expressed through cl, which is the common length - * ( basicall, min(len(a),len(b)) ), and dl, which is the delta between the + * ( basically, min(len(a),len(b)) ), and dl, which is the delta between the * two lengths, calculated as len(a)-len(b). All lengths are the number of * BN_ULONGs... */ @@ -929,7 +946,7 @@ int BN_to_montgomery(BIGNUM *r, const BIGNUM *a, BN_MONT_CTX *mont, return BN_mod_mul_montgomery(r, a, &(mont->RR), mont, ctx); } -void BN_with_flags(BIGNUM *dest, const BIGNUM *b, int n) +void BN_with_flags(BIGNUM *dest, const BIGNUM *b, int flags) { dest->d = b->d; dest->top = b->top; @@ -937,14 +954,14 @@ void BN_with_flags(BIGNUM *dest, const BIGNUM *b, int n) dest->neg = b->neg; dest->flags = ((dest->flags & BN_FLG_MALLOCED) | (b->flags & ~BN_FLG_MALLOCED) - | BN_FLG_STATIC_DATA | n); + | BN_FLG_STATIC_DATA | flags); } BN_GENCB *BN_GENCB_new(void) { BN_GENCB *ret; - if ((ret = (BN_GENCB *)OPENSSL_malloc(sizeof(BN_GENCB))) == NULL) { + if ((ret = OPENSSL_malloc(sizeof(*ret))) == NULL) { BNerr(BN_F_BN_GENCB_NEW, ERR_R_MALLOC_FAILURE); return (NULL); }