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715 lines
28 KiB
C
715 lines
28 KiB
C
/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:4;tab-width:4;coding:utf-8 -*-│
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│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi│
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╞══════════════════════════════════════════════════════════════════════════════╡
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│ Copyright The Mbed TLS Contributors │
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│ │
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│ Licensed under the Apache License, Version 2.0 (the "License"); │
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│ you may not use this file except in compliance with the License. │
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│ You may obtain a copy of the License at │
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│ │
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│ http://www.apache.org/licenses/LICENSE-2.0 │
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│ │
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│ Unless required by applicable law or agreed to in writing, software │
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│ distributed under the License is distributed on an "AS IS" BASIS, │
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│ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. │
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│ See the License for the specific language governing permissions and │
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│ limitations under the License. │
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╚─────────────────────────────────────────────────────────────────────────────*/
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#include "libc/str/str.h"
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#include "third_party/mbedtls/ccm.h"
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#include "third_party/mbedtls/common.h"
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#include "third_party/mbedtls/error.h"
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#include "third_party/mbedtls/platform.h"
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asm(".ident\t\"\\n\\n\
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Mbed TLS (Apache 2.0)\\n\
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Copyright ARM Limited\\n\
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Copyright Mbed TLS Contributors\"");
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asm(".include \"libc/disclaimer.inc\"");
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/* clang-format off */
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/**
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* @fileoverview NIST SP800-38C compliant CCM implementation
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*
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* This file provides an API for the CCM authenticated encryption mode
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* for block ciphers.
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*
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* CCM combines Counter mode encryption with CBC-MAC authentication
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* for 128-bit block ciphers.
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*
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* Input to CCM includes the following elements:
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* <ul><li>Payload - data that is both authenticated and encrypted.</li>
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* <li>Associated data (Adata) - data that is authenticated but not
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* encrypted, For example, a header.</li>
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* <li>Nonce - A unique value that is assigned to the payload and the
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* associated data.</li></ul>
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*
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* Definition of CCM:
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* http://csrc.nist.gov/publications/nistpubs/800-38C/SP800-38C_updated-July20_2007.pdf
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* RFC 3610 "Counter with CBC-MAC (CCM)"
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*
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* Related:
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* RFC 5116 "An Interface and Algorithms for Authenticated Encryption"
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*
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* Definition of CCM*:
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* IEEE 802.15.4 - IEEE Standard for Local and metropolitan area networks
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* Integer representation is fixed most-significant-octet-first order and
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* the representation of octets is most-significant-bit-first order. This is
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* consistent with RFC 3610.
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*/
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#define CCM_VALIDATE_RET( cond ) \
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MBEDTLS_INTERNAL_VALIDATE_RET( cond, MBEDTLS_ERR_CCM_BAD_INPUT )
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#define CCM_VALIDATE( cond ) \
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MBEDTLS_INTERNAL_VALIDATE( cond )
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#define CCM_ENCRYPT 0
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#define CCM_DECRYPT 1
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/**
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* \brief This function initializes the specified CCM context,
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* to make references valid, and prepare the context
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* for mbedtls_ccm_setkey() or mbedtls_ccm_free().
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*
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* \param ctx The CCM context to initialize. This must not be \c NULL.
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*/
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void mbedtls_ccm_init( mbedtls_ccm_context *ctx )
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{
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CCM_VALIDATE( ctx );
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mbedtls_platform_zeroize( ctx, sizeof( mbedtls_ccm_context ) );
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}
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/**
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* \brief This function initializes the CCM context set in the
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* \p ctx parameter and sets the encryption key.
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*
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* \param ctx The CCM context to initialize. This must be an initialized
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* context.
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* \param cipher The 128-bit block cipher to use.
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* \param key The encryption key. This must not be \c NULL.
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* \param keybits The key size in bits. This must be acceptable by the cipher.
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*
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* \return \c 0 on success.
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* \return A CCM or cipher-specific error code on failure.
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*/
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int mbedtls_ccm_setkey( mbedtls_ccm_context *ctx,
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mbedtls_cipher_id_t cipher,
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const unsigned char *key,
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unsigned int keybits )
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{
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int ret = MBEDTLS_ERR_THIS_CORRUPTION;
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const mbedtls_cipher_info_t *cipher_info;
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CCM_VALIDATE_RET( ctx );
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CCM_VALIDATE_RET( key );
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cipher_info = mbedtls_cipher_info_from_values( cipher, keybits,
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MBEDTLS_MODE_ECB );
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if( cipher_info == NULL )
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return( MBEDTLS_ERR_CCM_BAD_INPUT );
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if( cipher_info->block_size != 16 )
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return( MBEDTLS_ERR_CCM_BAD_INPUT );
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mbedtls_cipher_free( &ctx->cipher_ctx );
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if( ( ret = mbedtls_cipher_setup( &ctx->cipher_ctx, cipher_info ) ) != 0 )
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return( ret );
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if( ( ret = mbedtls_cipher_setkey( &ctx->cipher_ctx, key, keybits,
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MBEDTLS_ENCRYPT ) ) != 0 )
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{
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return( ret );
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}
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return( 0 );
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}
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/**
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* \brief This function releases and clears the specified CCM context
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* and underlying cipher sub-context.
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*
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* \param ctx The CCM context to clear. If this is \c NULL, the function
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* has no effect. Otherwise, this must be initialized.
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*/
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void mbedtls_ccm_free( mbedtls_ccm_context *ctx )
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{
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if( ctx == NULL )
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return;
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mbedtls_cipher_free( &ctx->cipher_ctx );
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mbedtls_platform_zeroize( ctx, sizeof( mbedtls_ccm_context ) );
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}
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/*
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* Macros for common operations.
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* Results in smaller compiled code than static inline functions.
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*/
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/*
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* Update the CBC-MAC state in y using a block in b
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* (Always using b as the source helps the compiler optimise a bit better.)
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*/
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#define UPDATE_CBC_MAC \
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for( i = 0; i < 16; i++ ) \
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y[i] ^= b[i]; \
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\
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if( ( ret = mbedtls_cipher_update( &ctx->cipher_ctx, y, 16, y, &olen ) ) != 0 ) \
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return( ret );
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/*
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* Encrypt or decrypt a partial block with CTR
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* Warning: using b for temporary storage! src and dst must not be b!
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* This avoids allocating one more 16 bytes buffer while allowing src == dst.
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*/
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#define CTR_CRYPT( dst, src, len ) \
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do \
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{ \
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if( ( ret = mbedtls_cipher_update( &ctx->cipher_ctx, ctr, \
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16, b, &olen ) ) != 0 ) \
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{ \
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return( ret ); \
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} \
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\
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for( i = 0; i < (len); i++ ) \
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(dst)[i] = (src)[i] ^ b[i]; \
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} while( 0 )
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/*
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* Authenticated encryption or decryption
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*/
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static int ccm_auth_crypt( mbedtls_ccm_context *ctx, int mode, size_t length,
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const unsigned char *iv, size_t iv_len,
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const unsigned char *add, size_t add_len,
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const unsigned char *input, unsigned char *output,
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unsigned char *tag, size_t tag_len )
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{
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int ret = MBEDTLS_ERR_THIS_CORRUPTION;
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unsigned char i;
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unsigned char q;
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size_t len_left, olen;
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unsigned char b[16];
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unsigned char y[16];
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unsigned char ctr[16];
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const unsigned char *src;
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unsigned char *dst;
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/*
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* Check length requirements: SP800-38C A.1
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* Additional requirement: a < 2^16 - 2^8 to simplify the code.
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* 'length' checked later (when writing it to the first block)
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*
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* Also, loosen the requirements to enable support for CCM* (IEEE 802.15.4).
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*/
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if( tag_len == 2 || tag_len > 16 || tag_len % 2 != 0 )
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return( MBEDTLS_ERR_CCM_BAD_INPUT );
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/* Also implies q is within bounds */
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if( iv_len < 7 || iv_len > 13 )
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return( MBEDTLS_ERR_CCM_BAD_INPUT );
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if( add_len >= 0xFF00 )
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return( MBEDTLS_ERR_CCM_BAD_INPUT );
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q = 16 - 1 - (unsigned char) iv_len;
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/*
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* First block B_0:
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* 0 .. 0 flags
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* 1 .. iv_len nonce (aka iv)
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* iv_len+1 .. 15 length
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*
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* With flags as (bits):
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* 7 0
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* 6 add present?
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* 5 .. 3 (t - 2) / 2
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* 2 .. 0 q - 1
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*/
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b[0] = 0;
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b[0] |= ( add_len > 0 ) << 6;
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b[0] |= ( ( tag_len - 2 ) / 2 ) << 3;
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b[0] |= q - 1;
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memcpy( b + 1, iv, iv_len );
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for( i = 0, len_left = length; i < q; i++, len_left >>= 8 )
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b[15-i] = (unsigned char)( len_left & 0xFF );
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if( len_left > 0 )
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return( MBEDTLS_ERR_CCM_BAD_INPUT );
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/* Start CBC-MAC with first block */
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memset( y, 0, 16 );
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UPDATE_CBC_MAC;
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/*
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* If there is additional data, update CBC-MAC with
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* add_len, add, 0 (padding to a block boundary)
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*/
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if( add_len > 0 )
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{
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size_t use_len;
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len_left = add_len;
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src = add;
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memset( b, 0, 16 );
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b[0] = (unsigned char)( ( add_len >> 8 ) & 0xFF );
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b[1] = (unsigned char)( ( add_len ) & 0xFF );
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use_len = len_left < 16 - 2 ? len_left : 16 - 2;
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memcpy( b + 2, src, use_len );
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len_left -= use_len;
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src += use_len;
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UPDATE_CBC_MAC;
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while( len_left > 0 )
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{
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use_len = len_left > 16 ? 16 : len_left;
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memset( b, 0, 16 );
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memcpy( b, src, use_len );
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UPDATE_CBC_MAC;
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len_left -= use_len;
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src += use_len;
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}
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}
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/*
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* Prepare counter block for encryption:
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* 0 .. 0 flags
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* 1 .. iv_len nonce (aka iv)
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* iv_len+1 .. 15 counter (initially 1)
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*
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* With flags as (bits):
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* 7 .. 3 0
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* 2 .. 0 q - 1
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*/
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ctr[0] = q - 1;
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memcpy( ctr + 1, iv, iv_len );
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memset( ctr + 1 + iv_len, 0, q );
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ctr[15] = 1;
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/*
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* Authenticate and {en,de}crypt the message.
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*
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* The only difference between encryption and decryption is
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* the respective order of authentication and {en,de}cryption.
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*/
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len_left = length;
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src = input;
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dst = output;
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while( len_left > 0 )
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{
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size_t use_len = len_left > 16 ? 16 : len_left;
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if( mode == CCM_ENCRYPT )
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{
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memset( b, 0, 16 );
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memcpy( b, src, use_len );
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UPDATE_CBC_MAC;
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}
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CTR_CRYPT( dst, src, use_len );
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if( mode == CCM_DECRYPT )
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{
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memset( b, 0, 16 );
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memcpy( b, dst, use_len );
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UPDATE_CBC_MAC;
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}
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dst += use_len;
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src += use_len;
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len_left -= use_len;
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/*
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* Increment counter.
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* No need to check for overflow thanks to the length check above.
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*/
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for( i = 0; i < q; i++ )
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if( ++ctr[15-i] != 0 )
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break;
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}
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/*
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* Authentication: reset counter and crypt/mask internal tag
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*/
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for( i = 0; i < q; i++ )
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ctr[15-i] = 0;
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CTR_CRYPT( y, y, 16 );
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memcpy( tag, y, tag_len );
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return( 0 );
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}
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/**
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* \brief This function encrypts a buffer using CCM*.
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*
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* \note The tag is written to a separate buffer. To concatenate
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* the \p tag with the \p output, as done in <em>RFC-3610:
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* Counter with CBC-MAC (CCM)</em>, use
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* \p tag = \p output + \p length, and make sure that the
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* output buffer is at least \p length + \p tag_len wide.
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*
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* \note When using this function in a variable tag length context,
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* the tag length has to be encoded into the \p iv passed to
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* this function.
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*
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* \param ctx The CCM context to use for encryption. This must be
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* initialized and bound to a key.
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* \param length The length of the input data in Bytes.
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* \param iv The initialization vector (nonce). This must be a readable
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* buffer of at least \p iv_len Bytes.
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* \param iv_len The length of the nonce in Bytes: 7, 8, 9, 10, 11, 12,
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* or 13. The length L of the message length field is
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* 15 - \p iv_len.
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* \param add The additional data field. This must be a readable buffer of
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* at least \p add_len Bytes.
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* \param add_len The length of additional data in Bytes.
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* This must be less than 2^16 - 2^8.
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* \param input The buffer holding the input data. If \p length is greater
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* than zero, \p input must be a readable buffer of at least
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* that length.
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* \param output The buffer holding the output data. If \p length is greater
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* than zero, \p output must be a writable buffer of at least
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* that length.
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* \param tag The buffer holding the authentication field. This must be a
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* writable buffer of at least \p tag_len Bytes.
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* \param tag_len The length of the authentication field to generate in Bytes:
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* 0, 4, 6, 8, 10, 12, 14 or 16.
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*
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* \warning Passing \c 0 as \p tag_len means that the message is no
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* longer authenticated.
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*
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* \return \c 0 on success.
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* \return A CCM or cipher-specific error code on failure.
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*/
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int mbedtls_ccm_star_encrypt_and_tag( mbedtls_ccm_context *ctx, size_t length,
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const unsigned char *iv, size_t iv_len,
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const unsigned char *add, size_t add_len,
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const unsigned char *input, unsigned char *output,
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unsigned char *tag, size_t tag_len )
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{
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CCM_VALIDATE_RET( ctx );
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CCM_VALIDATE_RET( iv );
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CCM_VALIDATE_RET( add_len == 0 || add );
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CCM_VALIDATE_RET( length == 0 || input );
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CCM_VALIDATE_RET( length == 0 || output );
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CCM_VALIDATE_RET( tag_len == 0 || tag );
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return( ccm_auth_crypt( ctx, CCM_ENCRYPT, length, iv, iv_len,
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add, add_len, input, output, tag, tag_len ) );
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}
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/**
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* \brief This function encrypts a buffer using CCM.
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*
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* \note The tag is written to a separate buffer. To concatenate
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* the \p tag with the \p output, as done in <em>RFC-3610:
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* Counter with CBC-MAC (CCM)</em>, use
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* \p tag = \p output + \p length, and make sure that the
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* output buffer is at least \p length + \p tag_len wide.
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*
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* \param ctx The CCM context to use for encryption. This must be
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* initialized and bound to a key.
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* \param length The length of the input data in Bytes.
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* \param iv The initialization vector (nonce). This must be a readable
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* buffer of at least \p iv_len Bytes.
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* \param iv_len The length of the nonce in Bytes: 7, 8, 9, 10, 11, 12,
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* or 13. The length L of the message length field is
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* 15 - \p iv_len.
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* \param add The additional data field. If \p add_len is greater than
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* zero, \p add must be a readable buffer of at least that
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* length.
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* \param add_len The length of additional data in Bytes.
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* This must be less than `2^16 - 2^8`.
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* \param input The buffer holding the input data. If \p length is greater
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* than zero, \p input must be a readable buffer of at least
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* that length.
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* \param output The buffer holding the output data. If \p length is greater
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* than zero, \p output must be a writable buffer of at least
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* that length.
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* \param tag The buffer holding the authentication field. This must be a
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* writable buffer of at least \p tag_len Bytes.
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* \param tag_len The length of the authentication field to generate in Bytes:
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* 4, 6, 8, 10, 12, 14 or 16.
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*
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* \return \c 0 on success.
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* \return A CCM or cipher-specific error code on failure.
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*/
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int mbedtls_ccm_encrypt_and_tag( mbedtls_ccm_context *ctx, size_t length,
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const unsigned char *iv, size_t iv_len,
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const unsigned char *add, size_t add_len,
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const unsigned char *input, unsigned char *output,
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unsigned char *tag, size_t tag_len )
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{
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CCM_VALIDATE_RET( ctx );
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CCM_VALIDATE_RET( iv );
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CCM_VALIDATE_RET( add_len == 0 || add );
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CCM_VALIDATE_RET( length == 0 || input );
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CCM_VALIDATE_RET( length == 0 || output );
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CCM_VALIDATE_RET( tag_len == 0 || tag );
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if( tag_len == 0 )
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return( MBEDTLS_ERR_CCM_BAD_INPUT );
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return( mbedtls_ccm_star_encrypt_and_tag( ctx, length, iv, iv_len, add,
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add_len, input, output, tag, tag_len ) );
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}
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/**
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* \brief This function performs a CCM* authenticated decryption of a
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* buffer.
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*
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* \note When using this function in a variable tag length context,
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* the tag length has to be decoded from \p iv and passed to
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* this function as \p tag_len. (\p tag needs to be adjusted
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* accordingly.)
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*
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* \param ctx The CCM context to use for decryption. This must be
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* initialized and bound to a key.
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* \param length The length of the input data in Bytes.
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* \param iv The initialization vector (nonce). This must be a readable
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* buffer of at least \p iv_len Bytes.
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* \param iv_len The length of the nonce in Bytes: 7, 8, 9, 10, 11, 12,
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* or 13. The length L of the message length field is
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* 15 - \p iv_len.
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|
* \param add The additional data field. This must be a readable buffer of
|
|
* at least that \p add_len Bytes.
|
|
* \param add_len The length of additional data in Bytes.
|
|
* This must be less than 2^16 - 2^8.
|
|
* \param input The buffer holding the input data. If \p length is greater
|
|
* than zero, \p input must be a readable buffer of at least
|
|
* that length.
|
|
* \param output The buffer holding the output data. If \p length is greater
|
|
* than zero, \p output must be a writable buffer of at least
|
|
* that length.
|
|
* \param tag The buffer holding the authentication field. This must be a
|
|
* readable buffer of at least \p tag_len Bytes.
|
|
* \param tag_len The length of the authentication field in Bytes.
|
|
* 0, 4, 6, 8, 10, 12, 14 or 16.
|
|
*
|
|
* \warning Passing \c 0 as \p tag_len means that the message is nos
|
|
* longer authenticated.
|
|
*
|
|
* \return \c 0 on success.
|
|
* \return #MBEDTLS_ERR_CCM_AUTH_FAILED if the tag does not match.
|
|
* \return A cipher-specific error code on calculation failure.
|
|
*/
|
|
int mbedtls_ccm_star_auth_decrypt( mbedtls_ccm_context *ctx, size_t length,
|
|
const unsigned char *iv, size_t iv_len,
|
|
const unsigned char *add, size_t add_len,
|
|
const unsigned char *input, unsigned char *output,
|
|
const unsigned char *tag, size_t tag_len )
|
|
{
|
|
int ret = MBEDTLS_ERR_THIS_CORRUPTION;
|
|
unsigned char check_tag[16];
|
|
unsigned char i;
|
|
int diff;
|
|
|
|
CCM_VALIDATE_RET( ctx );
|
|
CCM_VALIDATE_RET( iv );
|
|
CCM_VALIDATE_RET( add_len == 0 || add );
|
|
CCM_VALIDATE_RET( length == 0 || input );
|
|
CCM_VALIDATE_RET( length == 0 || output );
|
|
CCM_VALIDATE_RET( tag_len == 0 || tag );
|
|
|
|
if( ( ret = ccm_auth_crypt( ctx, CCM_DECRYPT, length,
|
|
iv, iv_len, add, add_len,
|
|
input, output, check_tag, tag_len ) ) != 0 )
|
|
{
|
|
return( ret );
|
|
}
|
|
|
|
/* Check tag in "constant-time" */
|
|
for( diff = 0, i = 0; i < tag_len; i++ )
|
|
diff |= tag[i] ^ check_tag[i];
|
|
|
|
if( diff != 0 )
|
|
{
|
|
mbedtls_platform_zeroize( output, length );
|
|
return( MBEDTLS_ERR_CCM_AUTH_FAILED );
|
|
}
|
|
|
|
return( 0 );
|
|
}
|
|
|
|
/**
|
|
* \brief This function performs a CCM authenticated decryption of a
|
|
* buffer.
|
|
*
|
|
* \param ctx The CCM context to use for decryption. This must be
|
|
* initialized and bound to a key.
|
|
* \param length The length of the input data in Bytes.
|
|
* \param iv The initialization vector (nonce). This must be a readable
|
|
* buffer of at least \p iv_len Bytes.
|
|
* \param iv_len The length of the nonce in Bytes: 7, 8, 9, 10, 11, 12,
|
|
* or 13. The length L of the message length field is
|
|
* 15 - \p iv_len.
|
|
* \param add The additional data field. This must be a readable buffer
|
|
* of at least that \p add_len Bytes..
|
|
* \param add_len The length of additional data in Bytes.
|
|
* This must be less than 2^16 - 2^8.
|
|
* \param input The buffer holding the input data. If \p length is greater
|
|
* than zero, \p input must be a readable buffer of at least
|
|
* that length.
|
|
* \param output The buffer holding the output data. If \p length is greater
|
|
* than zero, \p output must be a writable buffer of at least
|
|
* that length.
|
|
* \param tag The buffer holding the authentication field. This must be a
|
|
* readable buffer of at least \p tag_len Bytes.
|
|
* \param tag_len The length of the authentication field to generate in Bytes:
|
|
* 4, 6, 8, 10, 12, 14 or 16.
|
|
*
|
|
* \return \c 0 on success. This indicates that the message is
|
|
* authentic. \return #MBEDTLS_ERR_CCM_AUTH_FAILED if the tag does not
|
|
* match. \return A cipher-specific error code on calculation failure.
|
|
*/
|
|
int mbedtls_ccm_auth_decrypt( mbedtls_ccm_context *ctx, size_t length,
|
|
const unsigned char *iv, size_t iv_len,
|
|
const unsigned char *add, size_t add_len,
|
|
const unsigned char *input, unsigned char *output,
|
|
const unsigned char *tag, size_t tag_len )
|
|
{
|
|
CCM_VALIDATE_RET( ctx );
|
|
CCM_VALIDATE_RET( iv );
|
|
CCM_VALIDATE_RET( add || !add_len );
|
|
CCM_VALIDATE_RET( input || !length );
|
|
CCM_VALIDATE_RET( output || !length );
|
|
CCM_VALIDATE_RET( tag || !tag_len );
|
|
if( !tag_len )
|
|
return( MBEDTLS_ERR_CCM_BAD_INPUT );
|
|
return( mbedtls_ccm_star_auth_decrypt( ctx, length, iv, iv_len, add,
|
|
add_len, input, output, tag, tag_len ) );
|
|
}
|
|
|
|
#if defined(MBEDTLS_SELF_TEST) && defined(MBEDTLS_AES_C)
|
|
/*
|
|
* Examples 1 to 3 from SP800-38C Appendix C
|
|
*/
|
|
|
|
#define NB_TESTS 3
|
|
#define CCM_SELFTEST_PT_MAX_LEN 24
|
|
#define CCM_SELFTEST_CT_MAX_LEN 32
|
|
/*
|
|
* The data is the same for all tests, only the used length changes
|
|
*/
|
|
static const unsigned char key_test_data[] = {
|
|
0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47,
|
|
0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f
|
|
};
|
|
|
|
static const unsigned char iv_test_data[] = {
|
|
0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
|
|
0x18, 0x19, 0x1a, 0x1b
|
|
};
|
|
|
|
static const unsigned char ad_test_data[] = {
|
|
0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
|
|
0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
|
|
0x10, 0x11, 0x12, 0x13
|
|
};
|
|
|
|
static const unsigned char msg_test_data[CCM_SELFTEST_PT_MAX_LEN] = {
|
|
0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27,
|
|
0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f,
|
|
0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,
|
|
};
|
|
|
|
static const size_t iv_len_test_data [NB_TESTS] = { 7, 8, 12 };
|
|
static const size_t add_len_test_data[NB_TESTS] = { 8, 16, 20 };
|
|
static const size_t msg_len_test_data[NB_TESTS] = { 4, 16, 24 };
|
|
static const size_t tag_len_test_data[NB_TESTS] = { 4, 6, 8 };
|
|
|
|
static const unsigned char res_test_data[NB_TESTS][CCM_SELFTEST_CT_MAX_LEN] = {
|
|
{ 0x71, 0x62, 0x01, 0x5b, 0x4d, 0xac, 0x25, 0x5d },
|
|
{ 0xd2, 0xa1, 0xf0, 0xe0, 0x51, 0xea, 0x5f, 0x62,
|
|
0x08, 0x1a, 0x77, 0x92, 0x07, 0x3d, 0x59, 0x3d,
|
|
0x1f, 0xc6, 0x4f, 0xbf, 0xac, 0xcd },
|
|
{ 0xe3, 0xb2, 0x01, 0xa9, 0xf5, 0xb7, 0x1a, 0x7a,
|
|
0x9b, 0x1c, 0xea, 0xec, 0xcd, 0x97, 0xe7, 0x0b,
|
|
0x61, 0x76, 0xaa, 0xd9, 0xa4, 0x42, 0x8a, 0xa5,
|
|
0x48, 0x43, 0x92, 0xfb, 0xc1, 0xb0, 0x99, 0x51 }
|
|
};
|
|
|
|
/**
|
|
* \brief The CCM checkup routine.
|
|
*
|
|
* \return \c 0 on success.
|
|
* \return \c 1 on failure.
|
|
*/
|
|
int mbedtls_ccm_self_test( int verbose )
|
|
{
|
|
mbedtls_ccm_context ctx;
|
|
/*
|
|
* Some hardware accelerators require the input and output buffers
|
|
* would be in RAM, because the flash is not accessible.
|
|
* Use buffers on the stack to hold the test vectors data.
|
|
*/
|
|
unsigned char plaintext[CCM_SELFTEST_PT_MAX_LEN];
|
|
unsigned char ciphertext[CCM_SELFTEST_CT_MAX_LEN];
|
|
size_t i;
|
|
int ret = MBEDTLS_ERR_THIS_CORRUPTION;
|
|
|
|
mbedtls_ccm_init( &ctx );
|
|
|
|
if( mbedtls_ccm_setkey( &ctx, MBEDTLS_CIPHER_ID_AES, key_test_data,
|
|
8 * sizeof key_test_data ) != 0 )
|
|
{
|
|
if( verbose != 0 )
|
|
mbedtls_printf( " CCM: setup failed" );
|
|
|
|
return( 1 );
|
|
}
|
|
|
|
for( i = 0; i < NB_TESTS; i++ )
|
|
{
|
|
if( verbose != 0 )
|
|
mbedtls_printf( " CCM-AES #%u: ", (unsigned int) i + 1 );
|
|
|
|
mbedtls_platform_zeroize( plaintext, CCM_SELFTEST_PT_MAX_LEN );
|
|
mbedtls_platform_zeroize( ciphertext, CCM_SELFTEST_CT_MAX_LEN );
|
|
memcpy( plaintext, msg_test_data, msg_len_test_data[i] );
|
|
|
|
ret = mbedtls_ccm_encrypt_and_tag( &ctx, msg_len_test_data[i],
|
|
iv_test_data, iv_len_test_data[i],
|
|
ad_test_data, add_len_test_data[i],
|
|
plaintext, ciphertext,
|
|
ciphertext + msg_len_test_data[i],
|
|
tag_len_test_data[i] );
|
|
|
|
if( ret != 0 ||
|
|
timingsafe_bcmp( ciphertext, res_test_data[i],
|
|
msg_len_test_data[i] + tag_len_test_data[i] ) != 0 )
|
|
{
|
|
if( verbose != 0 )
|
|
mbedtls_printf( "failed\n" );
|
|
|
|
return( 1 );
|
|
}
|
|
mbedtls_platform_zeroize( plaintext, CCM_SELFTEST_PT_MAX_LEN );
|
|
|
|
ret = mbedtls_ccm_auth_decrypt( &ctx, msg_len_test_data[i],
|
|
iv_test_data, iv_len_test_data[i],
|
|
ad_test_data, add_len_test_data[i],
|
|
ciphertext, plaintext,
|
|
ciphertext + msg_len_test_data[i],
|
|
tag_len_test_data[i] );
|
|
|
|
if( ret != 0 ||
|
|
timingsafe_bcmp( plaintext, msg_test_data, msg_len_test_data[i] ) != 0 )
|
|
{
|
|
if( verbose != 0 )
|
|
mbedtls_printf( "failed\n" );
|
|
|
|
return( 1 );
|
|
}
|
|
|
|
if( verbose != 0 )
|
|
mbedtls_printf( "passed\n" );
|
|
}
|
|
|
|
mbedtls_ccm_free( &ctx );
|
|
|
|
if( verbose != 0 )
|
|
mbedtls_printf( "\n" );
|
|
|
|
return( 0 );
|
|
}
|
|
|
|
#endif /* MBEDTLS_SELF_TEST && MBEDTLS_AES_C */
|