aes_cbc_crypt.c revision 7c478bd95313f5f23a4c958a745db2134aa03244
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License, Version 1.0 only
* (the "License"). You may not use this file except in compliance
* with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2004 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#pragma ident "%Z%%M% %I% %E% SMI"
#include <sys/sysmacros.h>
#include <sys/systm.h>
#include <sys/crypto/common.h>
#include <sys/strsun.h>
#include "aes_cbc_crypt.h"
#include "aes_impl.h"
#ifndef _KERNEL
#include <strings.h>
#endif /* !_KERNEL */
/*
* Initialize by setting iov_or_mp to point to the current iovec or mp,
* and by setting current_offset to an offset within the current iovec or mp .
*/
static void
aes_init_ptrs(crypto_data_t *out, void **iov_or_mp, offset_t *current_offset)
{
offset_t offset;
switch (out->cd_format) {
case CRYPTO_DATA_RAW:
*current_offset = out->cd_offset;
break;
case CRYPTO_DATA_UIO: {
uio_t *uiop = out->cd_uio;
uintptr_t vec_idx;
offset = out->cd_offset;
for (vec_idx = 0; vec_idx < uiop->uio_iovcnt &&
offset >= uiop->uio_iov[vec_idx].iov_len;
offset -= uiop->uio_iov[vec_idx++].iov_len);
*current_offset = offset;
*iov_or_mp = (void *)vec_idx;
break;
}
case CRYPTO_DATA_MBLK: {
mblk_t *mp;
offset = out->cd_offset;
for (mp = out->cd_mp; mp != NULL && offset >= MBLKL(mp);
offset -= MBLKL(mp), mp = mp->b_cont);
*current_offset = offset;
*iov_or_mp = mp;
break;
}
} /* end switch */
}
/*
* Get pointers for where in the output to copy a block of encrypted or
* decrypted data. The iov_or_mp argument stores a pointer to the current
* iovec or mp, and offset stores an offset into the current iovec or mp.
*/
static void
aes_get_ptrs(crypto_data_t *out, void **iov_or_mp, offset_t *current_offset,
uint8_t **out_data_1, size_t *out_data_1_len, uint8_t **out_data_2)
{
offset_t offset;
switch (out->cd_format) {
case CRYPTO_DATA_RAW: {
iovec_t *iov;
offset = *current_offset;
iov = &out->cd_raw;
if ((offset + AES_BLOCK_LEN) <= iov->iov_len) {
/* one AES block fits */
*out_data_1 = (uint8_t *)iov->iov_base + offset;
*out_data_1_len = AES_BLOCK_LEN;
*out_data_2 = NULL;
*current_offset = offset + AES_BLOCK_LEN;
}
break;
}
case CRYPTO_DATA_UIO: {
uio_t *uio = out->cd_uio;
iovec_t *iov;
offset_t offset;
uintptr_t vec_idx;
uint8_t *p;
offset = *current_offset;
vec_idx = (uintptr_t)(*iov_or_mp);
iov = &uio->uio_iov[vec_idx];
p = (uint8_t *)iov->iov_base + offset;
*out_data_1 = p;
if (offset + AES_BLOCK_LEN <= iov->iov_len) {
/* can fit one AES block into this iov */
*out_data_1_len = AES_BLOCK_LEN;
*out_data_2 = NULL;
*current_offset = offset + AES_BLOCK_LEN;
} else {
/* one AES block spans two iovecs */
*out_data_1_len = iov->iov_len - offset;
if (vec_idx == uio->uio_iovcnt)
return;
vec_idx++;
iov = &uio->uio_iov[vec_idx];
*out_data_2 = (uint8_t *)iov->iov_base;
*current_offset = AES_BLOCK_LEN - *out_data_1_len;
}
*iov_or_mp = (void *)vec_idx;
break;
}
case CRYPTO_DATA_MBLK: {
mblk_t *mp;
uint8_t *p;
offset = *current_offset;
mp = (mblk_t *)*iov_or_mp;
p = mp->b_rptr + offset;
*out_data_1 = p;
if ((p + AES_BLOCK_LEN) <= mp->b_wptr) {
/* can fit one AES block into this mblk */
*out_data_1_len = AES_BLOCK_LEN;
*out_data_2 = NULL;
*current_offset = offset + AES_BLOCK_LEN;
} else {
/* one DES block spans two mblks */
*out_data_1_len = mp->b_wptr - p;
if ((mp = mp->b_cont) == NULL)
return;
*out_data_2 = mp->b_rptr;
*current_offset = (AES_BLOCK_LEN - *out_data_1_len);
}
*iov_or_mp = mp;
break;
}
} /* end switch */
}
/*
* Encrypt multiple blocks of data.
*/
/* ARGSUSED */
int
aes_encrypt_contiguous_blocks(aes_ctx_t *ctx, char *data, size_t length,
crypto_data_t *out)
{
/* EXPORT DELETE START */
size_t remainder = length;
size_t need;
uint8_t *datap = (uint8_t *)data;
uint8_t *blockp;
uint8_t *lastp;
uint32_t tmp[4];
void *iov_or_mp;
offset_t offset;
uint8_t *out_data_1;
uint8_t *out_data_2;
size_t out_data_1_len;
if (length + ctx->ac_remainder_len < AES_BLOCK_LEN) {
/* accumulate bytes here and return */
bcopy(datap,
(uint8_t *)ctx->ac_remainder + ctx->ac_remainder_len,
length);
ctx->ac_remainder_len += length;
ctx->ac_copy_to = datap;
return (0);
}
lastp = (uint8_t *)ctx->ac_iv;
if (out != NULL)
aes_init_ptrs(out, &iov_or_mp, &offset);
do {
/* Unprocessed data from last call. */
if (ctx->ac_remainder_len > 0) {
need = AES_BLOCK_LEN - ctx->ac_remainder_len;
if (need > remainder)
return (1);
bcopy(datap, &((uint8_t *)ctx->ac_remainder)
[ctx->ac_remainder_len], need);
blockp = (uint8_t *)ctx->ac_remainder;
} else {
blockp = datap;
}
/* don't write on the plaintext */
if (out != NULL) {
if (IS_P2ALIGNED(blockp, sizeof (uint32_t))) {
/* LINTED: pointer alignment */
tmp[0] = *(uint32_t *)blockp;
/* LINTED: pointer alignment */
tmp[1] = *(uint32_t *)&blockp[4];
/* LINTED: pointer alignment */
tmp[2] = *(uint32_t *)&blockp[8];
/* LINTED: pointer alignment */
tmp[3] = *(uint32_t *)&blockp[12];
} else {
uint8_t *tmp8 = (uint8_t *)tmp;
AES_COPY_BLOCK(blockp, tmp8);
}
blockp = (uint8_t *)tmp;
}
if (ctx->ac_flags & AES_CBC_MODE) {
/*
* XOR the previous cipher block or IV with the
* current clear block. Check for alignment.
*/
if (IS_P2ALIGNED(blockp, sizeof (uint32_t)) &&
IS_P2ALIGNED(lastp, sizeof (uint32_t))) {
/* LINTED: pointer alignment */
*(uint32_t *)&blockp[0] ^=
/* LINTED: pointer alignment */
*(uint32_t *)&lastp[0];
/* LINTED: pointer alignment */
*(uint32_t *)&blockp[4] ^=
/* LINTED: pointer alignment */
*(uint32_t *)&lastp[4];
/* LINTED: pointer alignment */
*(uint32_t *)&blockp[8] ^=
/* LINTED: pointer alignment */
*(uint32_t *)&lastp[8];
/* LINTED: pointer alignment */
*(uint32_t *)&blockp[12] ^=
/* LINTED: pointer alignment */
*(uint32_t *)&lastp[12];
} else {
AES_XOR_BLOCK(lastp, blockp);
}
}
if (out == NULL) {
aes_encrypt_block(ctx->ac_keysched, blockp, blockp);
ctx->ac_lastp = blockp;
lastp = blockp;
if (ctx->ac_remainder_len > 0) {
bcopy(blockp, ctx->ac_copy_to,
ctx->ac_remainder_len);
bcopy(blockp + ctx->ac_remainder_len, datap,
need);
}
} else {
aes_encrypt_block(ctx->ac_keysched, blockp, lastp);
aes_get_ptrs(out, &iov_or_mp, &offset, &out_data_1,
&out_data_1_len, &out_data_2);
/* copy block to where it belongs */
bcopy(lastp, out_data_1, out_data_1_len);
if (out_data_2 != NULL) {
bcopy(lastp + out_data_1_len, out_data_2,
AES_BLOCK_LEN - out_data_1_len);
}
/* update offset */
out->cd_offset += AES_BLOCK_LEN;
}
/* Update pointer to next block of data to be processed. */
if (ctx->ac_remainder_len != 0) {
datap += need;
ctx->ac_remainder_len = 0;
} else {
datap += AES_BLOCK_LEN;
}
remainder = (size_t)&data[length] - (size_t)datap;
/* Incomplete last block. */
if (remainder > 0 && remainder < AES_BLOCK_LEN) {
bcopy(datap, ctx->ac_remainder, remainder);
ctx->ac_remainder_len = remainder;
ctx->ac_copy_to = datap;
goto out;
}
ctx->ac_copy_to = NULL;
} while (remainder > 0);
out:
if (ctx->ac_lastp != NULL) {
uint8_t *iv8 = (uint8_t *)ctx->ac_iv;
uint8_t *last8 = (uint8_t *)ctx->ac_lastp;
if (IS_P2ALIGNED(ctx->ac_lastp, sizeof (uint32_t))) {
/* LINTED: pointer alignment */
*(uint32_t *)iv8 = *(uint32_t *)last8;
/* LINTED: pointer alignment */
*(uint32_t *)&iv8[4] = *(uint32_t *)&last8[4];
/* LINTED: pointer alignment */
*(uint32_t *)&iv8[8] = *(uint32_t *)&last8[8];
/* LINTED: pointer alignment */
*(uint32_t *)&iv8[12] = *(uint32_t *)&last8[12];
} else {
AES_COPY_BLOCK(last8, iv8);
}
ctx->ac_lastp = (uint8_t *)ctx->ac_iv;
}
/* EXPORT DELETE END */
return (0);
}
#define OTHER(a, ctx) \
(((a) == (ctx)->ac_lastblock) ? (ctx)->ac_iv : (ctx)->ac_lastblock)
/*
* Decrypt multiple blocks of data.
*/
/* ARGSUSED */
int
aes_decrypt_contiguous_blocks(aes_ctx_t *ctx, char *data, size_t length,
crypto_data_t *out)
{
/* EXPORT DELETE START */
size_t remainder = length;
size_t need;
uint8_t *datap = (uint8_t *)data;
uint8_t *blockp;
uint8_t *lastp;
uint32_t tmp[4];
void *iov_or_mp;
offset_t offset;
uint8_t *out_data_1;
uint8_t *out_data_2;
size_t out_data_1_len;
if (length + ctx->ac_remainder_len < AES_BLOCK_LEN) {
/* accumulate bytes here and return */
bcopy(datap,
(uint8_t *)ctx->ac_remainder + ctx->ac_remainder_len,
length);
ctx->ac_remainder_len += length;
ctx->ac_copy_to = datap;
return (0);
}
lastp = ctx->ac_lastp;
if (out != NULL)
aes_init_ptrs(out, &iov_or_mp, &offset);
do {
/* Unprocessed data from last call. */
if (ctx->ac_remainder_len > 0) {
need = AES_BLOCK_LEN - ctx->ac_remainder_len;
if (need > remainder)
return (1);
bcopy(datap, &((uint8_t *)ctx->ac_remainder)
[ctx->ac_remainder_len], need);
blockp = (uint8_t *)ctx->ac_remainder;
} else {
blockp = datap;
}
if (ctx->ac_flags & AES_CBC_MODE) {
/* Save current ciphertext block */
if (IS_P2ALIGNED(blockp, sizeof (uint32_t))) {
uint32_t *tmp32;
/* LINTED: pointer alignment */
tmp32 = (uint32_t *)OTHER((uint64_t *)lastp,
ctx);
/* LINTED: pointer alignment */
*tmp32++ = *(uint32_t *)blockp;
/* LINTED: pointer alignment */
*tmp32++ = *(uint32_t *)&blockp[4];
/* LINTED: pointer alignment */
*tmp32++ = *(uint32_t *)&blockp[8];
/* LINTED: pointer alignment */
*tmp32++ = *(uint32_t *)&blockp[12];
} else {
uint8_t *tmp8;
/* LINTED: pointer alignment */
tmp8 = (uint8_t *)OTHER((uint64_t *)lastp, ctx);
AES_COPY_BLOCK(blockp, tmp8);
}
}
if (out != NULL) {
aes_decrypt_block(ctx->ac_keysched, blockp,
(uint8_t *)tmp);
blockp = (uint8_t *)tmp;
} else {
aes_decrypt_block(ctx->ac_keysched, blockp, blockp);
}
if (ctx->ac_flags & AES_CBC_MODE) {
/*
* XOR the previous cipher block or IV with the
* currently decrypted block. Check for alignment.
*/
if (IS_P2ALIGNED(blockp, sizeof (uint32_t)) &&
IS_P2ALIGNED(lastp, sizeof (uint32_t))) {
/* LINTED: pointer alignment */
*(uint32_t *)blockp ^= *(uint32_t *)lastp;
/* LINTED: pointer alignment */
*(uint32_t *)&blockp[4] ^=
/* LINTED: pointer alignment */
*(uint32_t *)&lastp[4];
/* LINTED: pointer alignment */
*(uint32_t *)&blockp[8] ^=
/* LINTED: pointer alignment */
*(uint32_t *)&lastp[8];
/* LINTED: pointer alignment */
*(uint32_t *)&blockp[12] ^=
/* LINTED: pointer alignment */
*(uint32_t *)&lastp[12];
} else {
AES_XOR_BLOCK(lastp, blockp);
}
/* LINTED: pointer alignment */
lastp = (uint8_t *)OTHER((uint64_t *)lastp, ctx);
}
if (out != NULL) {
aes_get_ptrs(out, &iov_or_mp, &offset, &out_data_1,
&out_data_1_len, &out_data_2);
/* copy temporary block to where it belongs */
bcopy(&tmp, out_data_1, out_data_1_len);
if (out_data_2 != NULL) {
bcopy((uint8_t *)&tmp + out_data_1_len,
out_data_2, AES_BLOCK_LEN - out_data_1_len);
}
/* update offset */
out->cd_offset += AES_BLOCK_LEN;
} else if (ctx->ac_remainder_len > 0) {
/* copy temporary block to where it belongs */
bcopy(blockp, ctx->ac_copy_to, ctx->ac_remainder_len);
bcopy(blockp + ctx->ac_remainder_len, datap, need);
}
/* Update pointer to next block of data to be processed. */
if (ctx->ac_remainder_len != 0) {
datap += need;
ctx->ac_remainder_len = 0;
} else {
datap += AES_BLOCK_LEN;
}
remainder = (size_t)&data[length] - (size_t)datap;
/* Incomplete last block. */
if (remainder > 0 && remainder < AES_BLOCK_LEN) {
bcopy(datap, ctx->ac_remainder, remainder);
ctx->ac_remainder_len = remainder;
ctx->ac_lastp = lastp;
ctx->ac_copy_to = datap;
return (0);
}
ctx->ac_copy_to = NULL;
} while (remainder > 0);
ctx->ac_lastp = lastp;
/* EXPORT DELETE END */
return (0);
}