aes_wrap.c

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/* crypto/aes/aes_wrap.c */
/* Written by Dr Stephen N Henson ([email protected]) for the OpenSSL
 * project.
 */
/* ====================================================================
 * Copyright (c) 2008 The OpenSSL Project.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer. 
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. All advertising materials mentioning features or use of this
 *    software must display the following acknowledgment:
 *    "This product includes software developed by the OpenSSL Project
 *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
 *
 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
 *    endorse or promote products derived from this software without
 *    prior written permission. For written permission, please contact
 *    [email protected].
 *
 * 5. Products derived from this software may not be called "OpenSSL"
 *    nor may "OpenSSL" appear in their names without prior written
 *    permission of the OpenSSL Project.
 *
 * 6. Redistributions of any form whatsoever must retain the following
 *    acknowledgment:
 *    "This product includes software developed by the OpenSSL Project
 *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
 *
 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
 * EXPRESSED 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 OpenSSL PROJECT OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 * OF THE POSSIBILITY OF SUCH DAMAGE.
 * ====================================================================
 */

#include "cryptlib.h"
#include <openssl/aes.h>
#include <openssl/bio.h>

static const unsigned char default_iv[] = {
  0xA6, 0xA6, 0xA6, 0xA6, 0xA6, 0xA6, 0xA6, 0xA6,
};

int AES_wrap_key(AES_KEY *key, const unsigned char *iv,
        unsigned char *out,
        const unsigned char *in, unsigned int inlen)
    {
    unsigned char *A, B[16], *R;
    unsigned int i, j, t;
    if ((inlen & 0x7) || (inlen < 8))
        return -1;
    A = B;
    t = 1;
    memcpy(out + 8, in, inlen);
    if (!iv)
        iv = default_iv;

    memcpy(A, iv, 8);

    for (j = 0; j < 6; j++)
        {
        R = out + 8;
        for (i = 0; i < inlen; i += 8, t++, R += 8)
            {
            memcpy(B + 8, R, 8);
            AES_encrypt(B, B, key);
            A[7] ^= (unsigned char)(t & 0xff);
            if (t > 0xff)   
                {
                A[6] ^= (unsigned char)((t >> 8) & 0xff);
                A[5] ^= (unsigned char)((t >> 16) & 0xff);
                A[4] ^= (unsigned char)((t >> 24) & 0xff);
                }
            memcpy(R, B + 8, 8);
            }
        }
    memcpy(out, A, 8);
    return inlen + 8;
    }

int AES_unwrap_key(AES_KEY *key, const unsigned char *iv,
        unsigned char *out,
        const unsigned char *in, unsigned int inlen)
    {
    unsigned char *A, B[16], *R;
    unsigned int i, j, t;
    inlen -= 8;
    if (inlen & 0x7)
        return -1;
    if (inlen < 8)
        return -1;
    A = B;
    t =  6 * (inlen >> 3);
    memcpy(A, in, 8);
    memcpy(out, in + 8, inlen);
    for (j = 0; j < 6; j++)
        {
        R = out + inlen - 8;
        for (i = 0; i < inlen; i += 8, t--, R -= 8)
            {
            A[7] ^= (unsigned char)(t & 0xff);
            if (t > 0xff)   
                {
                A[6] ^= (unsigned char)((t >> 8) & 0xff);
                A[5] ^= (unsigned char)((t >> 16) & 0xff);
                A[4] ^= (unsigned char)((t >> 24) & 0xff);
                }
            memcpy(B + 8, R, 8);
            AES_decrypt(B, B, key);
            memcpy(R, B + 8, 8);
            }
        }
    if (!iv)
        iv = default_iv;
    if (memcmp(A, iv, 8))
        {
        OPENSSL_cleanse(out, inlen);
        return 0;
        }
    return inlen;
    }

#ifdef AES_WRAP_TEST

int AES_wrap_unwrap_test(const unsigned char *kek, int keybits,
             const unsigned char *iv,
             const unsigned char *eout,
             const unsigned char *key, int keylen)
    {
    unsigned char *otmp = NULL, *ptmp = NULL;
    int r, ret = 0;
    AES_KEY wctx;
    otmp = OPENSSL_malloc(keylen + 8);
    ptmp = OPENSSL_malloc(keylen);
    if (!otmp || !ptmp)
        return 0;
    if (AES_set_encrypt_key(kek, keybits, &wctx))
        goto err;
    r = AES_wrap_key(&wctx, iv, otmp, key, keylen);
    if (r <= 0)
        goto err;

    if (eout && memcmp(eout, otmp, keylen))
        goto err;
        
    if (AES_set_decrypt_key(kek, keybits, &wctx))
        goto err;
    r = AES_unwrap_key(&wctx, iv, ptmp, otmp, r);

    if (memcmp(key, ptmp, keylen))
        goto err;

    ret = 1;

    err:
    if (otmp)
        OPENSSL_free(otmp);
    if (ptmp)
        OPENSSL_free(ptmp);

    return ret;

    }



int main(int argc, char **argv)
{

static const unsigned char kek[] = {
  0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
  0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
  0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
  0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f
};

static const unsigned char key[] = {
  0x00, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77,
  0x88, 0x99, 0xaa, 0xbb, 0xcc, 0xdd, 0xee, 0xff,
  0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
  0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f
};

static const unsigned char e1[] = {
  0x1f, 0xa6, 0x8b, 0x0a, 0x81, 0x12, 0xb4, 0x47,
  0xae, 0xf3, 0x4b, 0xd8, 0xfb, 0x5a, 0x7b, 0x82,
  0x9d, 0x3e, 0x86, 0x23, 0x71, 0xd2, 0xcf, 0xe5
};

static const unsigned char e2[] = {
  0x96, 0x77, 0x8b, 0x25, 0xae, 0x6c, 0xa4, 0x35,
  0xf9, 0x2b, 0x5b, 0x97, 0xc0, 0x50, 0xae, 0xd2,
  0x46, 0x8a, 0xb8, 0xa1, 0x7a, 0xd8, 0x4e, 0x5d
};

static const unsigned char e3[] = {
  0x64, 0xe8, 0xc3, 0xf9, 0xce, 0x0f, 0x5b, 0xa2,
  0x63, 0xe9, 0x77, 0x79, 0x05, 0x81, 0x8a, 0x2a,
  0x93, 0xc8, 0x19, 0x1e, 0x7d, 0x6e, 0x8a, 0xe7
};

static const unsigned char e4[] = {
  0x03, 0x1d, 0x33, 0x26, 0x4e, 0x15, 0xd3, 0x32,
  0x68, 0xf2, 0x4e, 0xc2, 0x60, 0x74, 0x3e, 0xdc,
  0xe1, 0xc6, 0xc7, 0xdd, 0xee, 0x72, 0x5a, 0x93,
  0x6b, 0xa8, 0x14, 0x91, 0x5c, 0x67, 0x62, 0xd2
};

static const unsigned char e5[] = {
  0xa8, 0xf9, 0xbc, 0x16, 0x12, 0xc6, 0x8b, 0x3f,
  0xf6, 0xe6, 0xf4, 0xfb, 0xe3, 0x0e, 0x71, 0xe4,
  0x76, 0x9c, 0x8b, 0x80, 0xa3, 0x2c, 0xb8, 0x95,
  0x8c, 0xd5, 0xd1, 0x7d, 0x6b, 0x25, 0x4d, 0xa1
};

static const unsigned char e6[] = {
  0x28, 0xc9, 0xf4, 0x04, 0xc4, 0xb8, 0x10, 0xf4,
  0xcb, 0xcc, 0xb3, 0x5c, 0xfb, 0x87, 0xf8, 0x26,
  0x3f, 0x57, 0x86, 0xe2, 0xd8, 0x0e, 0xd3, 0x26,
  0xcb, 0xc7, 0xf0, 0xe7, 0x1a, 0x99, 0xf4, 0x3b,
  0xfb, 0x98, 0x8b, 0x9b, 0x7a, 0x02, 0xdd, 0x21
};

    AES_KEY wctx, xctx;
    int ret;
    ret = AES_wrap_unwrap_test(kek, 128, NULL, e1, key, 16);
    fprintf(stderr, "Key test result %d\n", ret);
    ret = AES_wrap_unwrap_test(kek, 192, NULL, e2, key, 16);
    fprintf(stderr, "Key test result %d\n", ret);
    ret = AES_wrap_unwrap_test(kek, 256, NULL, e3, key, 16);
    fprintf(stderr, "Key test result %d\n", ret);
    ret = AES_wrap_unwrap_test(kek, 192, NULL, e4, key, 24);
    fprintf(stderr, "Key test result %d\n", ret);
    ret = AES_wrap_unwrap_test(kek, 256, NULL, e5, key, 24);
    fprintf(stderr, "Key test result %d\n", ret);
    ret = AES_wrap_unwrap_test(kek, 256, NULL, e6, key, 32);
    fprintf(stderr, "Key test result %d\n", ret);
}
    
    
#endif