/* -*- mode: c; c-basic-offset: 4; indent-tabs-mode: nil -*- */
/* lib/crypto/openssl/enc_provider/camellia.c */
/*
* Copyright (C) 2003, 2007, 2008, 2009, 2010 by the Massachusetts Institute of
* Technology. All rights reserved.
*
* Export of this software from the United States of America may
* require a specific license from the United States Government.
* It is the responsibility of any person or organization contemplating
* export to obtain such a license before exporting.
*
* WITHIN THAT CONSTRAINT, permission to use, copy, modify, and
* distribute this software and its documentation for any purpose and
* without fee is hereby granted, provided that the above copyright
* notice appear in all copies and that both that copyright notice and
* this permission notice appear in supporting documentation, and that
* the name of M.I.T. not be used in advertising or publicity pertaining
* to distribution of the software without specific, written prior
* permission. Furthermore if you modify this software you must label
* your software as modified software and not distribute it in such a
* fashion that it might be confused with the original M.I.T. software.
* M.I.T. makes no representations about the suitability of
* this software for any purpose. It is provided "as is" without express
* or implied warranty.
*/
#include "crypto_int.h"
#include <openssl/evp.h>
#include <openssl/camellia.h>
#include <openssl/modes.h>
static krb5_error_code
cbc_enc(krb5_key key, const krb5_data *ivec, krb5_crypto_iov *data,
size_t num_data);
static krb5_error_code
cbc_decr(krb5_key key, const krb5_data *ivec, krb5_crypto_iov *data,
size_t num_data);
static krb5_error_code
cts_encr(krb5_key key, const krb5_data *ivec, krb5_crypto_iov *data,
size_t num_data, size_t dlen);
static krb5_error_code
cts_decr(krb5_key key, const krb5_data *ivec, krb5_crypto_iov *data,
size_t num_data, size_t dlen);
#define BLOCK_SIZE 16
#define NUM_BITS 8
#define IV_CTS_BUF_SIZE 16 /* 16 - hardcoded in CRYPTO_cts128_en/decrypt */
static void
xorblock(unsigned char *out, const unsigned char *in)
{
int z;
for (z = 0; z < CAMELLIA_BLOCK_SIZE / 4; z++) {
unsigned char *outptr = &out[z * 4];
unsigned char *inptr = (unsigned char *)&in[z * 4];
/*
* Use unaligned accesses. On x86, this will probably still be faster
* than multiple byte accesses for unaligned data, and for aligned data
* should be far better. (One test indicated about 2.4% faster
* encryption for 1024-byte messages.)
*
* If some other CPU has really slow unaligned-word or byte accesses,
* perhaps this function (or the load/store helpers?) should test for
* alignment first.
*
* If byte accesses are faster than unaligned words, we may need to
* conditionalize on CPU type, as that may be hard to determine
* automatically.
*/
store_32_n(load_32_n(outptr) ^ load_32_n(inptr), outptr);
}
}
static const EVP_CIPHER *
map_mode(unsigned int len)
{
if (len==16)
return EVP_camellia_128_cbc();
if (len==32)
return EVP_camellia_256_cbc();
else
return NULL;
}
/* Encrypt one block using CBC. */
static krb5_error_code
cbc_enc(krb5_key key, const krb5_data *ivec, krb5_crypto_iov *data,
size_t num_data)
{
int ret, olen = BLOCK_SIZE;
unsigned char iblock[BLOCK_SIZE], oblock[BLOCK_SIZE];
EVP_CIPHER_CTX *ctx;
struct iov_cursor cursor;
ctx = EVP_CIPHER_CTX_new();
if (ctx == NULL)
return ENOMEM;
ret = EVP_EncryptInit_ex(ctx, map_mode(key->keyblock.length),
NULL, key->keyblock.contents, (ivec) ? (unsigned char*)ivec->data : NULL);
if (ret == 0) {
EVP_CIPHER_CTX_free(ctx);
return KRB5_CRYPTO_INTERNAL;
}
k5_iov_cursor_init(&cursor, data, num_data, BLOCK_SIZE, FALSE);
k5_iov_cursor_get(&cursor, iblock);
EVP_CIPHER_CTX_set_padding(ctx,0);
ret = EVP_EncryptUpdate(ctx, oblock, &olen, iblock, BLOCK_SIZE);
if (ret == 1)
k5_iov_cursor_put(&cursor, oblock);
EVP_CIPHER_CTX_free(ctx);
zap(iblock, BLOCK_SIZE);
zap(oblock, BLOCK_SIZE);
return (ret == 1) ? 0 : KRB5_CRYPTO_INTERNAL;
}
/* Decrypt one block using CBC. */
static krb5_error_code
cbc_decr(krb5_key key, const krb5_data *ivec, krb5_crypto_iov *data,
size_t num_data)
{
int ret = 0, olen = BLOCK_SIZE;
unsigned char iblock[BLOCK_SIZE], oblock[BLOCK_SIZE];
EVP_CIPHER_CTX *ctx;
struct iov_cursor cursor;
ctx = EVP_CIPHER_CTX_new();
if (ctx == NULL)
return ENOMEM;
ret = EVP_DecryptInit_ex(ctx, map_mode(key->keyblock.length),
NULL, key->keyblock.contents, (ivec) ? (unsigned char*)ivec->data : NULL);
if (ret == 0) {
EVP_CIPHER_CTX_free(ctx);
return KRB5_CRYPTO_INTERNAL;
}
k5_iov_cursor_init(&cursor, data, num_data, BLOCK_SIZE, FALSE);
k5_iov_cursor_get(&cursor, iblock);
EVP_CIPHER_CTX_set_padding(ctx,0);
ret = EVP_DecryptUpdate(ctx, oblock, &olen, iblock, BLOCK_SIZE);
if (ret == 1)
k5_iov_cursor_put(&cursor, oblock);
EVP_CIPHER_CTX_free(ctx);
zap(iblock, BLOCK_SIZE);
zap(oblock, BLOCK_SIZE);
return (ret == 1) ? 0 : KRB5_CRYPTO_INTERNAL;
}
static krb5_error_code
cts_encr(krb5_key key, const krb5_data *ivec, krb5_crypto_iov *data,
size_t num_data, size_t dlen)
{
int ret = 0;
size_t size = 0;
unsigned char *oblock = NULL, *dbuf = NULL;
unsigned char iv_cts[IV_CTS_BUF_SIZE];
struct iov_cursor cursor;
CAMELLIA_KEY enck;
memset(iv_cts,0,sizeof(iv_cts));
if (ivec && ivec->data){
if (ivec->length != sizeof(iv_cts))
return KRB5_CRYPTO_INTERNAL;
memcpy(iv_cts, ivec->data,ivec->length);
}
oblock = OPENSSL_malloc(dlen);
if (!oblock){
return ENOMEM;
}
dbuf = OPENSSL_malloc(dlen);
if (!dbuf){
OPENSSL_free(oblock);
return ENOMEM;
}
k5_iov_cursor_init(&cursor, data, num_data, dlen, FALSE);
k5_iov_cursor_get(&cursor, dbuf);
Camellia_set_key(key->keyblock.contents, NUM_BITS * key->keyblock.length,
&enck);
size = CRYPTO_cts128_encrypt((unsigned char *)dbuf, oblock, dlen, &enck,
iv_cts, (cbc128_f)Camellia_cbc_encrypt);
if (size <= 0)
ret = KRB5_CRYPTO_INTERNAL;
else
k5_iov_cursor_put(&cursor, oblock);
if (!ret && ivec && ivec->data)
memcpy(ivec->data, iv_cts, sizeof(iv_cts));
zap(oblock, dlen);
zap(dbuf, dlen);
OPENSSL_free(oblock);
OPENSSL_free(dbuf);
return ret;
}
static krb5_error_code
cts_decr(krb5_key key, const krb5_data *ivec, krb5_crypto_iov *data,
size_t num_data, size_t dlen)
{
int ret = 0;
size_t size = 0;
unsigned char *oblock = NULL;
unsigned char *dbuf = NULL;
unsigned char iv_cts[IV_CTS_BUF_SIZE];
struct iov_cursor cursor;
CAMELLIA_KEY deck;
memset(iv_cts,0,sizeof(iv_cts));
if (ivec && ivec->data){
if (ivec->length != sizeof(iv_cts))
return KRB5_CRYPTO_INTERNAL;
memcpy(iv_cts, ivec->data,ivec->length);
}
oblock = OPENSSL_malloc(dlen);
if (!oblock)
return ENOMEM;
dbuf = OPENSSL_malloc(dlen);
if (!dbuf){
OPENSSL_free(oblock);
return ENOMEM;
}
Camellia_set_key(key->keyblock.contents, NUM_BITS * key->keyblock.length,
&deck);
k5_iov_cursor_init(&cursor, data, num_data, dlen, FALSE);
k5_iov_cursor_get(&cursor, dbuf);
size = CRYPTO_cts128_decrypt((unsigned char *)dbuf, oblock,
dlen, &deck,
iv_cts, (cbc128_f)Camellia_cbc_encrypt);
if (size <= 0)
ret = KRB5_CRYPTO_INTERNAL;
else
k5_iov_cursor_put(&cursor, oblock);
if (!ret && ivec && ivec->data)
memcpy(ivec->data, iv_cts, sizeof(iv_cts));
zap(oblock, dlen);
zap(dbuf, dlen);
OPENSSL_free(oblock);
OPENSSL_free(dbuf);
return ret;
}
static krb5_error_code
krb5int_camellia_encrypt(krb5_key key, const krb5_data *ivec,
krb5_crypto_iov *data, size_t num_data)
{
int ret = 0;
size_t input_length, nblocks;
input_length = iov_total_length(data, num_data, FALSE);
nblocks = (input_length + BLOCK_SIZE - 1) / BLOCK_SIZE;
if (nblocks == 1) {
if (input_length != BLOCK_SIZE)
return KRB5_BAD_MSIZE;
ret = cbc_enc(key, ivec, data, num_data);
} else if (nblocks > 1) {
ret = cts_encr(key, ivec, data, num_data, input_length);
}
return ret;
}
static krb5_error_code
krb5int_camellia_decrypt(krb5_key key, const krb5_data *ivec,
krb5_crypto_iov *data, size_t num_data)
{
int ret = 0;
size_t input_length, nblocks;
input_length = iov_total_length(data, num_data, FALSE);
nblocks = (input_length + BLOCK_SIZE - 1) / BLOCK_SIZE;
if (nblocks == 1) {
if (input_length != BLOCK_SIZE)
return KRB5_BAD_MSIZE;
ret = cbc_decr(key, ivec, data, num_data);
} else if (nblocks > 1) {
ret = cts_decr(key, ivec, data, num_data, input_length);
}
return ret;
}
krb5_error_code
krb5int_camellia_cbc_mac(krb5_key key, const krb5_crypto_iov *data,
size_t num_data, const krb5_data *iv,
krb5_data *output)
{
CAMELLIA_KEY enck;
unsigned char blockY[CAMELLIA_BLOCK_SIZE], blockB[CAMELLIA_BLOCK_SIZE];
struct iov_cursor cursor;
if (output->length < CAMELLIA_BLOCK_SIZE)
return KRB5_BAD_MSIZE;
Camellia_set_key(key->keyblock.contents,
NUM_BITS * key->keyblock.length, &enck);
if (iv != NULL)
memcpy(blockY, iv->data, CAMELLIA_BLOCK_SIZE);
else
memset(blockY, 0, CAMELLIA_BLOCK_SIZE);
k5_iov_cursor_init(&cursor, data, num_data, CAMELLIA_BLOCK_SIZE, FALSE);
while (k5_iov_cursor_get(&cursor, blockB)) {
xorblock(blockB, blockY);
Camellia_ecb_encrypt(blockB, blockY, &enck, 1);
}
output->length = CAMELLIA_BLOCK_SIZE;
memcpy(output->data, blockY, CAMELLIA_BLOCK_SIZE);
return 0;
}
static krb5_error_code
krb5int_camellia_init_state (const krb5_keyblock *key, krb5_keyusage usage,
krb5_data *state)
{
state->length = 16;
state->data = (void *) malloc(16);
if (state->data == NULL)
return ENOMEM;
memset(state->data, 0, state->length);
return 0;
}
const struct krb5_enc_provider krb5int_enc_camellia128 = {
16,
16, 16,
krb5int_camellia_encrypt,
krb5int_camellia_decrypt,
krb5int_camellia_cbc_mac,
krb5int_camellia_init_state,
krb5int_default_free_state
};
const struct krb5_enc_provider krb5int_enc_camellia256 = {
16,
32, 32,
krb5int_camellia_encrypt,
krb5int_camellia_decrypt,
krb5int_camellia_cbc_mac,
krb5int_camellia_init_state,
krb5int_default_free_state
};