480 lines
14 KiB
C
480 lines
14 KiB
C
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/* ====================================================================
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* Copyright (c) 2011 The OpenSSL Project. All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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*
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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*
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in
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* the documentation and/or other materials provided with the
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* distribution.
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*
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* 3. All advertising materials mentioning features or use of this
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* software must display the following acknowledgment:
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* "This product includes software developed by the OpenSSL Project
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* for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
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*
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* 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
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* endorse or promote products derived from this software without
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* prior written permission. For written permission, please contact
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* openssl-core@openssl.org.
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*
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* 5. Products derived from this software may not be called "OpenSSL"
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* nor may "OpenSSL" appear in their names without prior written
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* permission of the OpenSSL Project.
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*
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* 6. Redistributions of any form whatsoever must retain the following
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* acknowledgment:
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* "This product includes software developed by the OpenSSL Project
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* for use in the OpenSSL Toolkit (http://www.openssl.org/)"
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*
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* THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
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* EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
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* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
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* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
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* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
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* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
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* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
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* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
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* OF THE POSSIBILITY OF SUCH DAMAGE.
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* ====================================================================
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*/
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#include <openssl/crypto.h>
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#include "modes_lcl.h"
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#include <string.h>
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#ifndef MODES_DEBUG
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# ifndef NDEBUG
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# define NDEBUG
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# endif
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#endif
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#include <assert.h>
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/*
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* First you setup M and L parameters and pass the key schedule. This is
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* called once per session setup...
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*/
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void CRYPTO_ccm128_init(CCM128_CONTEXT *ctx,
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unsigned int M, unsigned int L, void *key,
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block128_f block)
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{
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memset(ctx->nonce.c, 0, sizeof(ctx->nonce.c));
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ctx->nonce.c[0] = ((u8)(L - 1) & 7) | (u8)(((M - 2) / 2) & 7) << 3;
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ctx->blocks = 0;
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ctx->block = block;
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ctx->key = key;
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}
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/* !!! Following interfaces are to be called *once* per packet !!! */
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/* Then you setup per-message nonce and pass the length of the message */
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int CRYPTO_ccm128_setiv(CCM128_CONTEXT *ctx,
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const unsigned char *nonce, size_t nlen, size_t mlen)
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{
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unsigned int L = ctx->nonce.c[0] & 7; /* the L parameter */
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if (nlen < (14 - L))
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return -1; /* nonce is too short */
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if (sizeof(mlen) == 8 && L >= 3) {
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ctx->nonce.c[8] = (u8)(mlen >> (56 % (sizeof(mlen) * 8)));
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ctx->nonce.c[9] = (u8)(mlen >> (48 % (sizeof(mlen) * 8)));
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ctx->nonce.c[10] = (u8)(mlen >> (40 % (sizeof(mlen) * 8)));
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ctx->nonce.c[11] = (u8)(mlen >> (32 % (sizeof(mlen) * 8)));
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} else
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ctx->nonce.u[1] = 0;
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ctx->nonce.c[12] = (u8)(mlen >> 24);
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ctx->nonce.c[13] = (u8)(mlen >> 16);
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ctx->nonce.c[14] = (u8)(mlen >> 8);
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ctx->nonce.c[15] = (u8)mlen;
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ctx->nonce.c[0] &= ~0x40; /* clear Adata flag */
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memcpy(&ctx->nonce.c[1], nonce, 14 - L);
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return 0;
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}
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/* Then you pass additional authentication data, this is optional */
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void CRYPTO_ccm128_aad(CCM128_CONTEXT *ctx,
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const unsigned char *aad, size_t alen)
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{
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unsigned int i;
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block128_f block = ctx->block;
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if (alen == 0)
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return;
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ctx->nonce.c[0] |= 0x40; /* set Adata flag */
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(*block) (ctx->nonce.c, ctx->cmac.c, ctx->key), ctx->blocks++;
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if (alen < (0x10000 - 0x100)) {
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ctx->cmac.c[0] ^= (u8)(alen >> 8);
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ctx->cmac.c[1] ^= (u8)alen;
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i = 2;
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} else if (sizeof(alen) == 8
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&& alen >= (size_t)1 << (32 % (sizeof(alen) * 8))) {
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ctx->cmac.c[0] ^= 0xFF;
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ctx->cmac.c[1] ^= 0xFF;
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ctx->cmac.c[2] ^= (u8)(alen >> (56 % (sizeof(alen) * 8)));
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ctx->cmac.c[3] ^= (u8)(alen >> (48 % (sizeof(alen) * 8)));
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ctx->cmac.c[4] ^= (u8)(alen >> (40 % (sizeof(alen) * 8)));
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ctx->cmac.c[5] ^= (u8)(alen >> (32 % (sizeof(alen) * 8)));
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ctx->cmac.c[6] ^= (u8)(alen >> 24);
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ctx->cmac.c[7] ^= (u8)(alen >> 16);
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ctx->cmac.c[8] ^= (u8)(alen >> 8);
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ctx->cmac.c[9] ^= (u8)alen;
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i = 10;
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} else {
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ctx->cmac.c[0] ^= 0xFF;
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ctx->cmac.c[1] ^= 0xFE;
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ctx->cmac.c[2] ^= (u8)(alen >> 24);
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ctx->cmac.c[3] ^= (u8)(alen >> 16);
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ctx->cmac.c[4] ^= (u8)(alen >> 8);
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ctx->cmac.c[5] ^= (u8)alen;
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i = 6;
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}
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do {
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for (; i < 16 && alen; ++i, ++aad, --alen)
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ctx->cmac.c[i] ^= *aad;
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(*block) (ctx->cmac.c, ctx->cmac.c, ctx->key), ctx->blocks++;
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i = 0;
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} while (alen);
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}
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/* Finally you encrypt or decrypt the message */
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/*
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* counter part of nonce may not be larger than L*8 bits, L is not larger
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* than 8, therefore 64-bit counter...
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*/
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static void ctr64_inc(unsigned char *counter)
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{
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unsigned int n = 8;
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u8 c;
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counter += 8;
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do {
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--n;
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c = counter[n];
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++c;
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counter[n] = c;
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if (c)
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return;
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} while (n);
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}
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int CRYPTO_ccm128_encrypt(CCM128_CONTEXT *ctx,
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const unsigned char *inp, unsigned char *out,
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size_t len)
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{
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size_t n;
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unsigned int i, L;
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unsigned char flags0 = ctx->nonce.c[0];
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block128_f block = ctx->block;
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void *key = ctx->key;
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union {
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u64 u[2];
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u8 c[16];
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} scratch;
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if (!(flags0 & 0x40))
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(*block) (ctx->nonce.c, ctx->cmac.c, key), ctx->blocks++;
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ctx->nonce.c[0] = L = flags0 & 7;
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for (n = 0, i = 15 - L; i < 15; ++i) {
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n |= ctx->nonce.c[i];
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ctx->nonce.c[i] = 0;
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n <<= 8;
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}
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n |= ctx->nonce.c[15]; /* reconstructed length */
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ctx->nonce.c[15] = 1;
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if (n != len)
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return -1; /* length mismatch */
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ctx->blocks += ((len + 15) >> 3) | 1;
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if (ctx->blocks > (U64(1) << 61))
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return -2; /* too much data */
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while (len >= 16) {
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#if defined(STRICT_ALIGNMENT)
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union {
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u64 u[2];
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u8 c[16];
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} temp;
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memcpy(temp.c, inp, 16);
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ctx->cmac.u[0] ^= temp.u[0];
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ctx->cmac.u[1] ^= temp.u[1];
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#else
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ctx->cmac.u[0] ^= ((u64 *)inp)[0];
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ctx->cmac.u[1] ^= ((u64 *)inp)[1];
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#endif
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(*block) (ctx->cmac.c, ctx->cmac.c, key);
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(*block) (ctx->nonce.c, scratch.c, key);
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ctr64_inc(ctx->nonce.c);
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#if defined(STRICT_ALIGNMENT)
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temp.u[0] ^= scratch.u[0];
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temp.u[1] ^= scratch.u[1];
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memcpy(out, temp.c, 16);
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#else
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((u64 *)out)[0] = scratch.u[0] ^ ((u64 *)inp)[0];
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((u64 *)out)[1] = scratch.u[1] ^ ((u64 *)inp)[1];
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#endif
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inp += 16;
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out += 16;
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len -= 16;
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}
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if (len) {
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for (i = 0; i < len; ++i)
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ctx->cmac.c[i] ^= inp[i];
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(*block) (ctx->cmac.c, ctx->cmac.c, key);
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(*block) (ctx->nonce.c, scratch.c, key);
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for (i = 0; i < len; ++i)
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out[i] = scratch.c[i] ^ inp[i];
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}
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for (i = 15 - L; i < 16; ++i)
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ctx->nonce.c[i] = 0;
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(*block) (ctx->nonce.c, scratch.c, key);
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ctx->cmac.u[0] ^= scratch.u[0];
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ctx->cmac.u[1] ^= scratch.u[1];
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ctx->nonce.c[0] = flags0;
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return 0;
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}
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int CRYPTO_ccm128_decrypt(CCM128_CONTEXT *ctx,
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const unsigned char *inp, unsigned char *out,
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size_t len)
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{
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size_t n;
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unsigned int i, L;
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unsigned char flags0 = ctx->nonce.c[0];
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block128_f block = ctx->block;
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void *key = ctx->key;
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union {
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u64 u[2];
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u8 c[16];
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} scratch;
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if (!(flags0 & 0x40))
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(*block) (ctx->nonce.c, ctx->cmac.c, key);
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ctx->nonce.c[0] = L = flags0 & 7;
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for (n = 0, i = 15 - L; i < 15; ++i) {
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n |= ctx->nonce.c[i];
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ctx->nonce.c[i] = 0;
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n <<= 8;
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}
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n |= ctx->nonce.c[15]; /* reconstructed length */
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ctx->nonce.c[15] = 1;
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if (n != len)
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return -1;
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while (len >= 16) {
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#if defined(STRICT_ALIGNMENT)
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union {
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u64 u[2];
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u8 c[16];
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} temp;
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#endif
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(*block) (ctx->nonce.c, scratch.c, key);
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ctr64_inc(ctx->nonce.c);
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#if defined(STRICT_ALIGNMENT)
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memcpy(temp.c, inp, 16);
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ctx->cmac.u[0] ^= (scratch.u[0] ^= temp.u[0]);
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ctx->cmac.u[1] ^= (scratch.u[1] ^= temp.u[1]);
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memcpy(out, scratch.c, 16);
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#else
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ctx->cmac.u[0] ^= (((u64 *)out)[0] = scratch.u[0] ^ ((u64 *)inp)[0]);
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ctx->cmac.u[1] ^= (((u64 *)out)[1] = scratch.u[1] ^ ((u64 *)inp)[1]);
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#endif
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(*block) (ctx->cmac.c, ctx->cmac.c, key);
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inp += 16;
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out += 16;
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len -= 16;
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}
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if (len) {
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(*block) (ctx->nonce.c, scratch.c, key);
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for (i = 0; i < len; ++i)
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ctx->cmac.c[i] ^= (out[i] = scratch.c[i] ^ inp[i]);
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(*block) (ctx->cmac.c, ctx->cmac.c, key);
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}
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for (i = 15 - L; i < 16; ++i)
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ctx->nonce.c[i] = 0;
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(*block) (ctx->nonce.c, scratch.c, key);
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ctx->cmac.u[0] ^= scratch.u[0];
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ctx->cmac.u[1] ^= scratch.u[1];
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ctx->nonce.c[0] = flags0;
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return 0;
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}
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static void ctr64_add(unsigned char *counter, size_t inc)
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{
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size_t n = 8, val = 0;
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counter += 8;
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do {
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--n;
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val += counter[n] + (inc & 0xff);
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counter[n] = (unsigned char)val;
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val >>= 8; /* carry bit */
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inc >>= 8;
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} while (n && (inc || val));
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}
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int CRYPTO_ccm128_encrypt_ccm64(CCM128_CONTEXT *ctx,
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const unsigned char *inp, unsigned char *out,
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size_t len, ccm128_f stream)
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{
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size_t n;
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||
|
|
unsigned int i, L;
|
||
|
|
unsigned char flags0 = ctx->nonce.c[0];
|
||
|
|
block128_f block = ctx->block;
|
||
|
|
void *key = ctx->key;
|
||
|
|
union {
|
||
|
|
u64 u[2];
|
||
|
|
u8 c[16];
|
||
|
|
} scratch;
|
||
|
|
|
||
|
|
if (!(flags0 & 0x40))
|
||
|
|
(*block) (ctx->nonce.c, ctx->cmac.c, key), ctx->blocks++;
|
||
|
|
|
||
|
|
ctx->nonce.c[0] = L = flags0 & 7;
|
||
|
|
for (n = 0, i = 15 - L; i < 15; ++i) {
|
||
|
|
n |= ctx->nonce.c[i];
|
||
|
|
ctx->nonce.c[i] = 0;
|
||
|
|
n <<= 8;
|
||
|
|
}
|
||
|
|
n |= ctx->nonce.c[15]; /* reconstructed length */
|
||
|
|
ctx->nonce.c[15] = 1;
|
||
|
|
|
||
|
|
if (n != len)
|
||
|
|
return -1; /* length mismatch */
|
||
|
|
|
||
|
|
ctx->blocks += ((len + 15) >> 3) | 1;
|
||
|
|
if (ctx->blocks > (U64(1) << 61))
|
||
|
|
return -2; /* too much data */
|
||
|
|
|
||
|
|
if ((n = len / 16)) {
|
||
|
|
(*stream) (inp, out, n, key, ctx->nonce.c, ctx->cmac.c);
|
||
|
|
n *= 16;
|
||
|
|
inp += n;
|
||
|
|
out += n;
|
||
|
|
len -= n;
|
||
|
|
if (len)
|
||
|
|
ctr64_add(ctx->nonce.c, n / 16);
|
||
|
|
}
|
||
|
|
|
||
|
|
if (len) {
|
||
|
|
for (i = 0; i < len; ++i)
|
||
|
|
ctx->cmac.c[i] ^= inp[i];
|
||
|
|
(*block) (ctx->cmac.c, ctx->cmac.c, key);
|
||
|
|
(*block) (ctx->nonce.c, scratch.c, key);
|
||
|
|
for (i = 0; i < len; ++i)
|
||
|
|
out[i] = scratch.c[i] ^ inp[i];
|
||
|
|
}
|
||
|
|
|
||
|
|
for (i = 15 - L; i < 16; ++i)
|
||
|
|
ctx->nonce.c[i] = 0;
|
||
|
|
|
||
|
|
(*block) (ctx->nonce.c, scratch.c, key);
|
||
|
|
ctx->cmac.u[0] ^= scratch.u[0];
|
||
|
|
ctx->cmac.u[1] ^= scratch.u[1];
|
||
|
|
|
||
|
|
ctx->nonce.c[0] = flags0;
|
||
|
|
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
int CRYPTO_ccm128_decrypt_ccm64(CCM128_CONTEXT *ctx,
|
||
|
|
const unsigned char *inp, unsigned char *out,
|
||
|
|
size_t len, ccm128_f stream)
|
||
|
|
{
|
||
|
|
size_t n;
|
||
|
|
unsigned int i, L;
|
||
|
|
unsigned char flags0 = ctx->nonce.c[0];
|
||
|
|
block128_f block = ctx->block;
|
||
|
|
void *key = ctx->key;
|
||
|
|
union {
|
||
|
|
u64 u[2];
|
||
|
|
u8 c[16];
|
||
|
|
} scratch;
|
||
|
|
|
||
|
|
if (!(flags0 & 0x40))
|
||
|
|
(*block) (ctx->nonce.c, ctx->cmac.c, key);
|
||
|
|
|
||
|
|
ctx->nonce.c[0] = L = flags0 & 7;
|
||
|
|
for (n = 0, i = 15 - L; i < 15; ++i) {
|
||
|
|
n |= ctx->nonce.c[i];
|
||
|
|
ctx->nonce.c[i] = 0;
|
||
|
|
n <<= 8;
|
||
|
|
}
|
||
|
|
n |= ctx->nonce.c[15]; /* reconstructed length */
|
||
|
|
ctx->nonce.c[15] = 1;
|
||
|
|
|
||
|
|
if (n != len)
|
||
|
|
return -1;
|
||
|
|
|
||
|
|
if ((n = len / 16)) {
|
||
|
|
(*stream) (inp, out, n, key, ctx->nonce.c, ctx->cmac.c);
|
||
|
|
n *= 16;
|
||
|
|
inp += n;
|
||
|
|
out += n;
|
||
|
|
len -= n;
|
||
|
|
if (len)
|
||
|
|
ctr64_add(ctx->nonce.c, n / 16);
|
||
|
|
}
|
||
|
|
|
||
|
|
if (len) {
|
||
|
|
(*block) (ctx->nonce.c, scratch.c, key);
|
||
|
|
for (i = 0; i < len; ++i)
|
||
|
|
ctx->cmac.c[i] ^= (out[i] = scratch.c[i] ^ inp[i]);
|
||
|
|
(*block) (ctx->cmac.c, ctx->cmac.c, key);
|
||
|
|
}
|
||
|
|
|
||
|
|
for (i = 15 - L; i < 16; ++i)
|
||
|
|
ctx->nonce.c[i] = 0;
|
||
|
|
|
||
|
|
(*block) (ctx->nonce.c, scratch.c, key);
|
||
|
|
ctx->cmac.u[0] ^= scratch.u[0];
|
||
|
|
ctx->cmac.u[1] ^= scratch.u[1];
|
||
|
|
|
||
|
|
ctx->nonce.c[0] = flags0;
|
||
|
|
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
size_t CRYPTO_ccm128_tag(CCM128_CONTEXT *ctx, unsigned char *tag, size_t len)
|
||
|
|
{
|
||
|
|
unsigned int M = (ctx->nonce.c[0] >> 3) & 7; /* the M parameter */
|
||
|
|
|
||
|
|
M *= 2;
|
||
|
|
M += 2;
|
||
|
|
if (len < M)
|
||
|
|
return 0;
|
||
|
|
memcpy(tag, ctx->cmac.c, M);
|
||
|
|
return M;
|
||
|
|
}
|