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Diffstat (limited to 'source4/heimdal/lib/hcrypto/evp-aes-cts.c')
| -rw-r--r-- | source4/heimdal/lib/hcrypto/evp-aes-cts.c | 277 |
1 files changed, 277 insertions, 0 deletions
diff --git a/source4/heimdal/lib/hcrypto/evp-aes-cts.c b/source4/heimdal/lib/hcrypto/evp-aes-cts.c new file mode 100644 index 0000000000..60a538b7de --- /dev/null +++ b/source4/heimdal/lib/hcrypto/evp-aes-cts.c @@ -0,0 +1,277 @@ +/* + * Copyright (c) 2006 - 2007 Kungliga Tekniska Högskolan + * (Royal Institute of Technology, Stockholm, Sweden). + * 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. Neither the name of the Institute nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``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 INSTITUTE 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. + */ + +#ifdef HAVE_CONFIG_H +#include <config.h> +#endif + +RCSID("$Id$"); + +#define HC_DEPRECATED + +#include <sys/types.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <assert.h> + + +#include <krb5-types.h> + +#if defined(BUILD_KRB5_LIB) && defined(HAVE_OPENSSL) +#include <openssl/evp.h> +#include <openssl/aes.h> + +#define _hc_EVP_hcrypto_aes_128_cts _krb5_EVP_hcrypto_aes_128_cts +#define _hc_EVP_hcrypto_aes_192_cts _krb5_EVP_hcrypto_aes_192_cts +#define _hc_EVP_hcrypto_aes_256_cts _krb5_EVP_hcrypto_aes_256_cts + +const EVP_CIPHER * _krb5_EVP_hcrypto_aes_128_cts(void); +const EVP_CIPHER * _krb5_EVP_hcrypto_aes_192_cts(void); +const EVP_CIPHER * _krb5_EVP_hcrypto_aes_256_cts(void); + +#else +#include <evp.h> +#include <aes.h> + +#define _hc_EVP_hcrypto_aes_128_cts hc_EVP_hcrypto_aes_128_cts +#define _hc_EVP_hcrypto_aes_192_cts hc_EVP_hcrypto_aes_192_cts +#define _hc_EVP_hcrypto_aes_256_cts hc_EVP_hcrypto_aes_256_cts + +#endif + +/* + * + */ + +static int +aes_cts_init(EVP_CIPHER_CTX *ctx, + const unsigned char * key, + const unsigned char * iv, + int encp) +{ + AES_KEY *k = ctx->cipher_data; + if (ctx->encrypt) + AES_set_encrypt_key(key, ctx->cipher->key_len * 8, k); + else + AES_set_decrypt_key(key, ctx->cipher->key_len * 8, k); + return 1; +} + +static void +_krb5_aes_cts_encrypt(const unsigned char *in, unsigned char *out, + size_t len, const AES_KEY *key, + unsigned char *ivec, const int encryptp) +{ + unsigned char tmp[AES_BLOCK_SIZE]; + int i; + + /* + * In the framework of kerberos, the length can never be shorter + * then at least one blocksize. + */ + + if (encryptp) { + + while(len > AES_BLOCK_SIZE) { + for (i = 0; i < AES_BLOCK_SIZE; i++) + tmp[i] = in[i] ^ ivec[i]; + AES_encrypt(tmp, out, key); + memcpy(ivec, out, AES_BLOCK_SIZE); + len -= AES_BLOCK_SIZE; + in += AES_BLOCK_SIZE; + out += AES_BLOCK_SIZE; + } + + for (i = 0; i < len; i++) + tmp[i] = in[i] ^ ivec[i]; + for (; i < AES_BLOCK_SIZE; i++) + tmp[i] = 0 ^ ivec[i]; + + AES_encrypt(tmp, out - AES_BLOCK_SIZE, key); + + memcpy(out, ivec, len); + memcpy(ivec, out - AES_BLOCK_SIZE, AES_BLOCK_SIZE); + + } else { + unsigned char tmp2[AES_BLOCK_SIZE]; + unsigned char tmp3[AES_BLOCK_SIZE]; + + while(len > AES_BLOCK_SIZE * 2) { + memcpy(tmp, in, AES_BLOCK_SIZE); + AES_decrypt(in, out, key); + for (i = 0; i < AES_BLOCK_SIZE; i++) + out[i] ^= ivec[i]; + memcpy(ivec, tmp, AES_BLOCK_SIZE); + len -= AES_BLOCK_SIZE; + in += AES_BLOCK_SIZE; + out += AES_BLOCK_SIZE; + } + + len -= AES_BLOCK_SIZE; + + memcpy(tmp, in, AES_BLOCK_SIZE); /* save last iv */ + AES_decrypt(in, tmp2, key); + + memcpy(tmp3, in + AES_BLOCK_SIZE, len); + memcpy(tmp3 + len, tmp2 + len, AES_BLOCK_SIZE - len); /* xor 0 */ + + for (i = 0; i < len; i++) + out[i + AES_BLOCK_SIZE] = tmp2[i] ^ tmp3[i]; + + AES_decrypt(tmp3, out, key); + for (i = 0; i < AES_BLOCK_SIZE; i++) + out[i] ^= ivec[i]; + memcpy(ivec, tmp, AES_BLOCK_SIZE); + } +} + +static int +aes_cts_do_cipher(EVP_CIPHER_CTX *ctx, + unsigned char *out, + const unsigned char *in, + unsigned int len) +{ + AES_KEY *k = ctx->cipher_data; + + if (len < AES_BLOCK_SIZE) + abort(); /* krb5_abortx(context, "invalid use of AES_CTS_encrypt"); */ + if (len == AES_BLOCK_SIZE) { + if (ctx->encrypt) + AES_encrypt(in, out, k); + else + AES_decrypt(in, out, k); + } else { + _krb5_aes_cts_encrypt(in, out, len, k, ctx->iv, ctx->encrypt); + } + + return 1; +} + + +static int +aes_cts_cleanup(EVP_CIPHER_CTX *ctx) +{ + memset(ctx->cipher_data, 0, sizeof(AES_KEY)); + return 1; +} + +/** + * The AES-128 cts cipher type (hcrypto) + * + * @return the AES-128 EVP_CIPHER pointer. + * + * @ingroup hcrypto_evp + */ + +const EVP_CIPHER * +_hc_EVP_hcrypto_aes_128_cts(void) +{ + static const EVP_CIPHER aes_128_cts = { + 0, + 1, + 16, + 16, + EVP_CIPH_CBC_MODE, + aes_cts_init, + aes_cts_do_cipher, + aes_cts_cleanup, + sizeof(AES_KEY), + NULL, + NULL, + NULL, + NULL + }; + + return &aes_128_cts; +} + +/** + * The AES-192 cts cipher type (hcrypto) + * + * @return the AES-192 EVP_CIPHER pointer. + * + * @ingroup hcrypto_evp + */ + +const EVP_CIPHER * +_hc_EVP_hcrypto_aes_192_cts(void) +{ + static const EVP_CIPHER aes_192_cts = { + 0, + 1, + 24, + 16, + EVP_CIPH_CBC_MODE, + aes_cts_init, + aes_cts_do_cipher, + aes_cts_cleanup, + sizeof(AES_KEY), + NULL, + NULL, + NULL, + NULL + }; + + return &aes_192_cts; +} + +/** + * The AES-256 cts cipher type (hcrypto) + * + * @return the AES-256 EVP_CIPHER pointer. + * + * @ingroup hcrypto_evp + */ + +const EVP_CIPHER * +_hc_EVP_hcrypto_aes_256_cts(void) +{ + static const EVP_CIPHER aes_256_cts = { + 0, + 1, + 32, + 16, + EVP_CIPH_CBC_MODE, + aes_cts_init, + aes_cts_do_cipher, + aes_cts_cleanup, + sizeof(AES_KEY), + NULL, + NULL, + NULL, + NULL + }; + + return &aes_256_cts; +} |