linux/arch/s390/crypto/aes_s390.c

856 lines
23 KiB
C

/*
* Cryptographic API.
*
* s390 implementation of the AES Cipher Algorithm.
*
* s390 Version:
* Copyright IBM Corp. 2005, 2007
* Author(s): Jan Glauber (jang@de.ibm.com)
* Sebastian Siewior (sebastian@breakpoint.cc> SW-Fallback
*
* Derived from "crypto/aes_generic.c"
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the Free
* Software Foundation; either version 2 of the License, or (at your option)
* any later version.
*
*/
#define KMSG_COMPONENT "aes_s390"
#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
#include <crypto/aes.h>
#include <crypto/algapi.h>
#include <crypto/internal/skcipher.h>
#include <linux/err.h>
#include <linux/module.h>
#include <linux/cpufeature.h>
#include <linux/init.h>
#include <linux/spinlock.h>
#include <linux/fips.h>
#include <crypto/xts.h>
#include <asm/cpacf.h>
static u8 *ctrblk;
static DEFINE_SPINLOCK(ctrblk_lock);
static cpacf_mask_t km_functions, kmc_functions, kmctr_functions;
struct s390_aes_ctx {
u8 key[AES_MAX_KEY_SIZE];
int key_len;
unsigned long fc;
union {
struct crypto_skcipher *blk;
struct crypto_cipher *cip;
} fallback;
};
struct s390_xts_ctx {
u8 key[32];
u8 pcc_key[32];
int key_len;
unsigned long fc;
struct crypto_skcipher *fallback;
};
static int setkey_fallback_cip(struct crypto_tfm *tfm, const u8 *in_key,
unsigned int key_len)
{
struct s390_aes_ctx *sctx = crypto_tfm_ctx(tfm);
int ret;
sctx->fallback.cip->base.crt_flags &= ~CRYPTO_TFM_REQ_MASK;
sctx->fallback.cip->base.crt_flags |= (tfm->crt_flags &
CRYPTO_TFM_REQ_MASK);
ret = crypto_cipher_setkey(sctx->fallback.cip, in_key, key_len);
if (ret) {
tfm->crt_flags &= ~CRYPTO_TFM_RES_MASK;
tfm->crt_flags |= (sctx->fallback.cip->base.crt_flags &
CRYPTO_TFM_RES_MASK);
}
return ret;
}
static int aes_set_key(struct crypto_tfm *tfm, const u8 *in_key,
unsigned int key_len)
{
struct s390_aes_ctx *sctx = crypto_tfm_ctx(tfm);
unsigned long fc;
/* Pick the correct function code based on the key length */
fc = (key_len == 16) ? CPACF_KM_AES_128 :
(key_len == 24) ? CPACF_KM_AES_192 :
(key_len == 32) ? CPACF_KM_AES_256 : 0;
/* Check if the function code is available */
sctx->fc = (fc && cpacf_test_func(&km_functions, fc)) ? fc : 0;
if (!sctx->fc)
return setkey_fallback_cip(tfm, in_key, key_len);
sctx->key_len = key_len;
memcpy(sctx->key, in_key, key_len);
return 0;
}
static void aes_encrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in)
{
struct s390_aes_ctx *sctx = crypto_tfm_ctx(tfm);
if (unlikely(!sctx->fc)) {
crypto_cipher_encrypt_one(sctx->fallback.cip, out, in);
return;
}
cpacf_km(sctx->fc, &sctx->key, out, in, AES_BLOCK_SIZE);
}
static void aes_decrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in)
{
struct s390_aes_ctx *sctx = crypto_tfm_ctx(tfm);
if (unlikely(!sctx->fc)) {
crypto_cipher_decrypt_one(sctx->fallback.cip, out, in);
return;
}
cpacf_km(sctx->fc | CPACF_DECRYPT,
&sctx->key, out, in, AES_BLOCK_SIZE);
}
static int fallback_init_cip(struct crypto_tfm *tfm)
{
const char *name = tfm->__crt_alg->cra_name;
struct s390_aes_ctx *sctx = crypto_tfm_ctx(tfm);
sctx->fallback.cip = crypto_alloc_cipher(name, 0,
CRYPTO_ALG_ASYNC | CRYPTO_ALG_NEED_FALLBACK);
if (IS_ERR(sctx->fallback.cip)) {
pr_err("Allocating AES fallback algorithm %s failed\n",
name);
return PTR_ERR(sctx->fallback.cip);
}
return 0;
}
static void fallback_exit_cip(struct crypto_tfm *tfm)
{
struct s390_aes_ctx *sctx = crypto_tfm_ctx(tfm);
crypto_free_cipher(sctx->fallback.cip);
sctx->fallback.cip = NULL;
}
static struct crypto_alg aes_alg = {
.cra_name = "aes",
.cra_driver_name = "aes-s390",
.cra_priority = 300,
.cra_flags = CRYPTO_ALG_TYPE_CIPHER |
CRYPTO_ALG_NEED_FALLBACK,
.cra_blocksize = AES_BLOCK_SIZE,
.cra_ctxsize = sizeof(struct s390_aes_ctx),
.cra_module = THIS_MODULE,
.cra_init = fallback_init_cip,
.cra_exit = fallback_exit_cip,
.cra_u = {
.cipher = {
.cia_min_keysize = AES_MIN_KEY_SIZE,
.cia_max_keysize = AES_MAX_KEY_SIZE,
.cia_setkey = aes_set_key,
.cia_encrypt = aes_encrypt,
.cia_decrypt = aes_decrypt,
}
}
};
static int setkey_fallback_blk(struct crypto_tfm *tfm, const u8 *key,
unsigned int len)
{
struct s390_aes_ctx *sctx = crypto_tfm_ctx(tfm);
unsigned int ret;
crypto_skcipher_clear_flags(sctx->fallback.blk, CRYPTO_TFM_REQ_MASK);
crypto_skcipher_set_flags(sctx->fallback.blk, tfm->crt_flags &
CRYPTO_TFM_REQ_MASK);
ret = crypto_skcipher_setkey(sctx->fallback.blk, key, len);
tfm->crt_flags &= ~CRYPTO_TFM_RES_MASK;
tfm->crt_flags |= crypto_skcipher_get_flags(sctx->fallback.blk) &
CRYPTO_TFM_RES_MASK;
return ret;
}
static int fallback_blk_dec(struct blkcipher_desc *desc,
struct scatterlist *dst, struct scatterlist *src,
unsigned int nbytes)
{
unsigned int ret;
struct crypto_blkcipher *tfm = desc->tfm;
struct s390_aes_ctx *sctx = crypto_blkcipher_ctx(tfm);
SKCIPHER_REQUEST_ON_STACK(req, sctx->fallback.blk);
skcipher_request_set_tfm(req, sctx->fallback.blk);
skcipher_request_set_callback(req, desc->flags, NULL, NULL);
skcipher_request_set_crypt(req, src, dst, nbytes, desc->info);
ret = crypto_skcipher_decrypt(req);
skcipher_request_zero(req);
return ret;
}
static int fallback_blk_enc(struct blkcipher_desc *desc,
struct scatterlist *dst, struct scatterlist *src,
unsigned int nbytes)
{
unsigned int ret;
struct crypto_blkcipher *tfm = desc->tfm;
struct s390_aes_ctx *sctx = crypto_blkcipher_ctx(tfm);
SKCIPHER_REQUEST_ON_STACK(req, sctx->fallback.blk);
skcipher_request_set_tfm(req, sctx->fallback.blk);
skcipher_request_set_callback(req, desc->flags, NULL, NULL);
skcipher_request_set_crypt(req, src, dst, nbytes, desc->info);
ret = crypto_skcipher_encrypt(req);
return ret;
}
static int ecb_aes_set_key(struct crypto_tfm *tfm, const u8 *in_key,
unsigned int key_len)
{
struct s390_aes_ctx *sctx = crypto_tfm_ctx(tfm);
unsigned long fc;
/* Pick the correct function code based on the key length */
fc = (key_len == 16) ? CPACF_KM_AES_128 :
(key_len == 24) ? CPACF_KM_AES_192 :
(key_len == 32) ? CPACF_KM_AES_256 : 0;
/* Check if the function code is available */
sctx->fc = (fc && cpacf_test_func(&km_functions, fc)) ? fc : 0;
if (!sctx->fc)
return setkey_fallback_blk(tfm, in_key, key_len);
sctx->key_len = key_len;
memcpy(sctx->key, in_key, key_len);
return 0;
}
static int ecb_aes_crypt(struct blkcipher_desc *desc, unsigned long modifier,
struct blkcipher_walk *walk)
{
struct s390_aes_ctx *sctx = crypto_blkcipher_ctx(desc->tfm);
unsigned int nbytes, n;
int ret;
ret = blkcipher_walk_virt(desc, walk);
while ((nbytes = walk->nbytes) >= AES_BLOCK_SIZE) {
/* only use complete blocks */
n = nbytes & ~(AES_BLOCK_SIZE - 1);
cpacf_km(sctx->fc | modifier, sctx->key,
walk->dst.virt.addr, walk->src.virt.addr, n);
ret = blkcipher_walk_done(desc, walk, nbytes - n);
}
return ret;
}
static int ecb_aes_encrypt(struct blkcipher_desc *desc,
struct scatterlist *dst, struct scatterlist *src,
unsigned int nbytes)
{
struct s390_aes_ctx *sctx = crypto_blkcipher_ctx(desc->tfm);
struct blkcipher_walk walk;
if (unlikely(!sctx->fc))
return fallback_blk_enc(desc, dst, src, nbytes);
blkcipher_walk_init(&walk, dst, src, nbytes);
return ecb_aes_crypt(desc, 0, &walk);
}
static int ecb_aes_decrypt(struct blkcipher_desc *desc,
struct scatterlist *dst, struct scatterlist *src,
unsigned int nbytes)
{
struct s390_aes_ctx *sctx = crypto_blkcipher_ctx(desc->tfm);
struct blkcipher_walk walk;
if (unlikely(!sctx->fc))
return fallback_blk_dec(desc, dst, src, nbytes);
blkcipher_walk_init(&walk, dst, src, nbytes);
return ecb_aes_crypt(desc, CPACF_DECRYPT, &walk);
}
static int fallback_init_blk(struct crypto_tfm *tfm)
{
const char *name = tfm->__crt_alg->cra_name;
struct s390_aes_ctx *sctx = crypto_tfm_ctx(tfm);
sctx->fallback.blk = crypto_alloc_skcipher(name, 0,
CRYPTO_ALG_ASYNC |
CRYPTO_ALG_NEED_FALLBACK);
if (IS_ERR(sctx->fallback.blk)) {
pr_err("Allocating AES fallback algorithm %s failed\n",
name);
return PTR_ERR(sctx->fallback.blk);
}
return 0;
}
static void fallback_exit_blk(struct crypto_tfm *tfm)
{
struct s390_aes_ctx *sctx = crypto_tfm_ctx(tfm);
crypto_free_skcipher(sctx->fallback.blk);
}
static struct crypto_alg ecb_aes_alg = {
.cra_name = "ecb(aes)",
.cra_driver_name = "ecb-aes-s390",
.cra_priority = 400, /* combo: aes + ecb */
.cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER |
CRYPTO_ALG_NEED_FALLBACK,
.cra_blocksize = AES_BLOCK_SIZE,
.cra_ctxsize = sizeof(struct s390_aes_ctx),
.cra_type = &crypto_blkcipher_type,
.cra_module = THIS_MODULE,
.cra_init = fallback_init_blk,
.cra_exit = fallback_exit_blk,
.cra_u = {
.blkcipher = {
.min_keysize = AES_MIN_KEY_SIZE,
.max_keysize = AES_MAX_KEY_SIZE,
.setkey = ecb_aes_set_key,
.encrypt = ecb_aes_encrypt,
.decrypt = ecb_aes_decrypt,
}
}
};
static int cbc_aes_set_key(struct crypto_tfm *tfm, const u8 *in_key,
unsigned int key_len)
{
struct s390_aes_ctx *sctx = crypto_tfm_ctx(tfm);
unsigned long fc;
/* Pick the correct function code based on the key length */
fc = (key_len == 16) ? CPACF_KMC_AES_128 :
(key_len == 24) ? CPACF_KMC_AES_192 :
(key_len == 32) ? CPACF_KMC_AES_256 : 0;
/* Check if the function code is available */
sctx->fc = (fc && cpacf_test_func(&kmc_functions, fc)) ? fc : 0;
if (!sctx->fc)
return setkey_fallback_blk(tfm, in_key, key_len);
sctx->key_len = key_len;
memcpy(sctx->key, in_key, key_len);
return 0;
}
static int cbc_aes_crypt(struct blkcipher_desc *desc, unsigned long modifier,
struct blkcipher_walk *walk)
{
struct s390_aes_ctx *sctx = crypto_blkcipher_ctx(desc->tfm);
unsigned int nbytes, n;
int ret;
struct {
u8 iv[AES_BLOCK_SIZE];
u8 key[AES_MAX_KEY_SIZE];
} param;
ret = blkcipher_walk_virt(desc, walk);
memcpy(param.iv, walk->iv, AES_BLOCK_SIZE);
memcpy(param.key, sctx->key, sctx->key_len);
while ((nbytes = walk->nbytes) >= AES_BLOCK_SIZE) {
/* only use complete blocks */
n = nbytes & ~(AES_BLOCK_SIZE - 1);
cpacf_kmc(sctx->fc | modifier, &param,
walk->dst.virt.addr, walk->src.virt.addr, n);
ret = blkcipher_walk_done(desc, walk, nbytes - n);
}
memcpy(walk->iv, param.iv, AES_BLOCK_SIZE);
return ret;
}
static int cbc_aes_encrypt(struct blkcipher_desc *desc,
struct scatterlist *dst, struct scatterlist *src,
unsigned int nbytes)
{
struct s390_aes_ctx *sctx = crypto_blkcipher_ctx(desc->tfm);
struct blkcipher_walk walk;
if (unlikely(!sctx->fc))
return fallback_blk_enc(desc, dst, src, nbytes);
blkcipher_walk_init(&walk, dst, src, nbytes);
return cbc_aes_crypt(desc, 0, &walk);
}
static int cbc_aes_decrypt(struct blkcipher_desc *desc,
struct scatterlist *dst, struct scatterlist *src,
unsigned int nbytes)
{
struct s390_aes_ctx *sctx = crypto_blkcipher_ctx(desc->tfm);
struct blkcipher_walk walk;
if (unlikely(!sctx->fc))
return fallback_blk_dec(desc, dst, src, nbytes);
blkcipher_walk_init(&walk, dst, src, nbytes);
return cbc_aes_crypt(desc, CPACF_DECRYPT, &walk);
}
static struct crypto_alg cbc_aes_alg = {
.cra_name = "cbc(aes)",
.cra_driver_name = "cbc-aes-s390",
.cra_priority = 400, /* combo: aes + cbc */
.cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER |
CRYPTO_ALG_NEED_FALLBACK,
.cra_blocksize = AES_BLOCK_SIZE,
.cra_ctxsize = sizeof(struct s390_aes_ctx),
.cra_type = &crypto_blkcipher_type,
.cra_module = THIS_MODULE,
.cra_init = fallback_init_blk,
.cra_exit = fallback_exit_blk,
.cra_u = {
.blkcipher = {
.min_keysize = AES_MIN_KEY_SIZE,
.max_keysize = AES_MAX_KEY_SIZE,
.ivsize = AES_BLOCK_SIZE,
.setkey = cbc_aes_set_key,
.encrypt = cbc_aes_encrypt,
.decrypt = cbc_aes_decrypt,
}
}
};
static int xts_fallback_setkey(struct crypto_tfm *tfm, const u8 *key,
unsigned int len)
{
struct s390_xts_ctx *xts_ctx = crypto_tfm_ctx(tfm);
unsigned int ret;
crypto_skcipher_clear_flags(xts_ctx->fallback, CRYPTO_TFM_REQ_MASK);
crypto_skcipher_set_flags(xts_ctx->fallback, tfm->crt_flags &
CRYPTO_TFM_REQ_MASK);
ret = crypto_skcipher_setkey(xts_ctx->fallback, key, len);
tfm->crt_flags &= ~CRYPTO_TFM_RES_MASK;
tfm->crt_flags |= crypto_skcipher_get_flags(xts_ctx->fallback) &
CRYPTO_TFM_RES_MASK;
return ret;
}
static int xts_fallback_decrypt(struct blkcipher_desc *desc,
struct scatterlist *dst, struct scatterlist *src,
unsigned int nbytes)
{
struct crypto_blkcipher *tfm = desc->tfm;
struct s390_xts_ctx *xts_ctx = crypto_blkcipher_ctx(tfm);
SKCIPHER_REQUEST_ON_STACK(req, xts_ctx->fallback);
unsigned int ret;
skcipher_request_set_tfm(req, xts_ctx->fallback);
skcipher_request_set_callback(req, desc->flags, NULL, NULL);
skcipher_request_set_crypt(req, src, dst, nbytes, desc->info);
ret = crypto_skcipher_decrypt(req);
skcipher_request_zero(req);
return ret;
}
static int xts_fallback_encrypt(struct blkcipher_desc *desc,
struct scatterlist *dst, struct scatterlist *src,
unsigned int nbytes)
{
struct crypto_blkcipher *tfm = desc->tfm;
struct s390_xts_ctx *xts_ctx = crypto_blkcipher_ctx(tfm);
SKCIPHER_REQUEST_ON_STACK(req, xts_ctx->fallback);
unsigned int ret;
skcipher_request_set_tfm(req, xts_ctx->fallback);
skcipher_request_set_callback(req, desc->flags, NULL, NULL);
skcipher_request_set_crypt(req, src, dst, nbytes, desc->info);
ret = crypto_skcipher_encrypt(req);
skcipher_request_zero(req);
return ret;
}
static int xts_aes_set_key(struct crypto_tfm *tfm, const u8 *in_key,
unsigned int key_len)
{
struct s390_xts_ctx *xts_ctx = crypto_tfm_ctx(tfm);
unsigned long fc;
int err;
err = xts_check_key(tfm, in_key, key_len);
if (err)
return err;
/* In fips mode only 128 bit or 256 bit keys are valid */
if (fips_enabled && key_len != 32 && key_len != 64) {
tfm->crt_flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
return -EINVAL;
}
/* Pick the correct function code based on the key length */
fc = (key_len == 32) ? CPACF_KM_XTS_128 :
(key_len == 64) ? CPACF_KM_XTS_256 : 0;
/* Check if the function code is available */
xts_ctx->fc = (fc && cpacf_test_func(&km_functions, fc)) ? fc : 0;
if (!xts_ctx->fc)
return xts_fallback_setkey(tfm, in_key, key_len);
/* Split the XTS key into the two subkeys */
key_len = key_len / 2;
xts_ctx->key_len = key_len;
memcpy(xts_ctx->key, in_key, key_len);
memcpy(xts_ctx->pcc_key, in_key + key_len, key_len);
return 0;
}
static int xts_aes_crypt(struct blkcipher_desc *desc, unsigned long modifier,
struct blkcipher_walk *walk)
{
struct s390_xts_ctx *xts_ctx = crypto_blkcipher_ctx(desc->tfm);
unsigned int offset, nbytes, n;
int ret;
struct {
u8 key[32];
u8 tweak[16];
u8 block[16];
u8 bit[16];
u8 xts[16];
} pcc_param;
struct {
u8 key[32];
u8 init[16];
} xts_param;
ret = blkcipher_walk_virt(desc, walk);
offset = xts_ctx->key_len & 0x10;
memset(pcc_param.block, 0, sizeof(pcc_param.block));
memset(pcc_param.bit, 0, sizeof(pcc_param.bit));
memset(pcc_param.xts, 0, sizeof(pcc_param.xts));
memcpy(pcc_param.tweak, walk->iv, sizeof(pcc_param.tweak));
memcpy(pcc_param.key + offset, xts_ctx->pcc_key, xts_ctx->key_len);
cpacf_pcc(xts_ctx->fc, pcc_param.key + offset);
memcpy(xts_param.key + offset, xts_ctx->key, xts_ctx->key_len);
memcpy(xts_param.init, pcc_param.xts, 16);
while ((nbytes = walk->nbytes) >= AES_BLOCK_SIZE) {
/* only use complete blocks */
n = nbytes & ~(AES_BLOCK_SIZE - 1);
cpacf_km(xts_ctx->fc | modifier, xts_param.key + offset,
walk->dst.virt.addr, walk->src.virt.addr, n);
ret = blkcipher_walk_done(desc, walk, nbytes - n);
}
return ret;
}
static int xts_aes_encrypt(struct blkcipher_desc *desc,
struct scatterlist *dst, struct scatterlist *src,
unsigned int nbytes)
{
struct s390_xts_ctx *xts_ctx = crypto_blkcipher_ctx(desc->tfm);
struct blkcipher_walk walk;
if (unlikely(!xts_ctx->fc))
return xts_fallback_encrypt(desc, dst, src, nbytes);
blkcipher_walk_init(&walk, dst, src, nbytes);
return xts_aes_crypt(desc, 0, &walk);
}
static int xts_aes_decrypt(struct blkcipher_desc *desc,
struct scatterlist *dst, struct scatterlist *src,
unsigned int nbytes)
{
struct s390_xts_ctx *xts_ctx = crypto_blkcipher_ctx(desc->tfm);
struct blkcipher_walk walk;
if (unlikely(!xts_ctx->fc))
return xts_fallback_decrypt(desc, dst, src, nbytes);
blkcipher_walk_init(&walk, dst, src, nbytes);
return xts_aes_crypt(desc, CPACF_DECRYPT, &walk);
}
static int xts_fallback_init(struct crypto_tfm *tfm)
{
const char *name = tfm->__crt_alg->cra_name;
struct s390_xts_ctx *xts_ctx = crypto_tfm_ctx(tfm);
xts_ctx->fallback = crypto_alloc_skcipher(name, 0,
CRYPTO_ALG_ASYNC |
CRYPTO_ALG_NEED_FALLBACK);
if (IS_ERR(xts_ctx->fallback)) {
pr_err("Allocating XTS fallback algorithm %s failed\n",
name);
return PTR_ERR(xts_ctx->fallback);
}
return 0;
}
static void xts_fallback_exit(struct crypto_tfm *tfm)
{
struct s390_xts_ctx *xts_ctx = crypto_tfm_ctx(tfm);
crypto_free_skcipher(xts_ctx->fallback);
}
static struct crypto_alg xts_aes_alg = {
.cra_name = "xts(aes)",
.cra_driver_name = "xts-aes-s390",
.cra_priority = 400, /* combo: aes + xts */
.cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER |
CRYPTO_ALG_NEED_FALLBACK,
.cra_blocksize = AES_BLOCK_SIZE,
.cra_ctxsize = sizeof(struct s390_xts_ctx),
.cra_type = &crypto_blkcipher_type,
.cra_module = THIS_MODULE,
.cra_init = xts_fallback_init,
.cra_exit = xts_fallback_exit,
.cra_u = {
.blkcipher = {
.min_keysize = 2 * AES_MIN_KEY_SIZE,
.max_keysize = 2 * AES_MAX_KEY_SIZE,
.ivsize = AES_BLOCK_SIZE,
.setkey = xts_aes_set_key,
.encrypt = xts_aes_encrypt,
.decrypt = xts_aes_decrypt,
}
}
};
static int ctr_aes_set_key(struct crypto_tfm *tfm, const u8 *in_key,
unsigned int key_len)
{
struct s390_aes_ctx *sctx = crypto_tfm_ctx(tfm);
unsigned long fc;
/* Pick the correct function code based on the key length */
fc = (key_len == 16) ? CPACF_KMCTR_AES_128 :
(key_len == 24) ? CPACF_KMCTR_AES_192 :
(key_len == 32) ? CPACF_KMCTR_AES_256 : 0;
/* Check if the function code is available */
sctx->fc = (fc && cpacf_test_func(&kmctr_functions, fc)) ? fc : 0;
if (!sctx->fc)
return setkey_fallback_blk(tfm, in_key, key_len);
sctx->key_len = key_len;
memcpy(sctx->key, in_key, key_len);
return 0;
}
static unsigned int __ctrblk_init(u8 *ctrptr, u8 *iv, unsigned int nbytes)
{
unsigned int i, n;
/* only use complete blocks, max. PAGE_SIZE */
memcpy(ctrptr, iv, AES_BLOCK_SIZE);
n = (nbytes > PAGE_SIZE) ? PAGE_SIZE : nbytes & ~(AES_BLOCK_SIZE - 1);
for (i = (n / AES_BLOCK_SIZE) - 1; i > 0; i--) {
memcpy(ctrptr + AES_BLOCK_SIZE, ctrptr, AES_BLOCK_SIZE);
crypto_inc(ctrptr + AES_BLOCK_SIZE, AES_BLOCK_SIZE);
ctrptr += AES_BLOCK_SIZE;
}
return n;
}
static int ctr_aes_crypt(struct blkcipher_desc *desc, unsigned long modifier,
struct blkcipher_walk *walk)
{
struct s390_aes_ctx *sctx = crypto_blkcipher_ctx(desc->tfm);
u8 buf[AES_BLOCK_SIZE], *ctrptr;
unsigned int n, nbytes;
int ret, locked;
locked = spin_trylock(&ctrblk_lock);
ret = blkcipher_walk_virt_block(desc, walk, AES_BLOCK_SIZE);
while ((nbytes = walk->nbytes) >= AES_BLOCK_SIZE) {
n = AES_BLOCK_SIZE;
if (nbytes >= 2*AES_BLOCK_SIZE && locked)
n = __ctrblk_init(ctrblk, walk->iv, nbytes);
ctrptr = (n > AES_BLOCK_SIZE) ? ctrblk : walk->iv;
cpacf_kmctr(sctx->fc | modifier, sctx->key,
walk->dst.virt.addr, walk->src.virt.addr,
n, ctrptr);
if (ctrptr == ctrblk)
memcpy(walk->iv, ctrptr + n - AES_BLOCK_SIZE,
AES_BLOCK_SIZE);
crypto_inc(walk->iv, AES_BLOCK_SIZE);
ret = blkcipher_walk_done(desc, walk, nbytes - n);
}
if (locked)
spin_unlock(&ctrblk_lock);
/*
* final block may be < AES_BLOCK_SIZE, copy only nbytes
*/
if (nbytes) {
cpacf_kmctr(sctx->fc | modifier, sctx->key,
buf, walk->src.virt.addr,
AES_BLOCK_SIZE, walk->iv);
memcpy(walk->dst.virt.addr, buf, nbytes);
crypto_inc(walk->iv, AES_BLOCK_SIZE);
ret = blkcipher_walk_done(desc, walk, 0);
}
return ret;
}
static int ctr_aes_encrypt(struct blkcipher_desc *desc,
struct scatterlist *dst, struct scatterlist *src,
unsigned int nbytes)
{
struct s390_aes_ctx *sctx = crypto_blkcipher_ctx(desc->tfm);
struct blkcipher_walk walk;
if (unlikely(!sctx->fc))
return fallback_blk_enc(desc, dst, src, nbytes);
blkcipher_walk_init(&walk, dst, src, nbytes);
return ctr_aes_crypt(desc, 0, &walk);
}
static int ctr_aes_decrypt(struct blkcipher_desc *desc,
struct scatterlist *dst, struct scatterlist *src,
unsigned int nbytes)
{
struct s390_aes_ctx *sctx = crypto_blkcipher_ctx(desc->tfm);
struct blkcipher_walk walk;
if (unlikely(!sctx->fc))
return fallback_blk_dec(desc, dst, src, nbytes);
blkcipher_walk_init(&walk, dst, src, nbytes);
return ctr_aes_crypt(desc, CPACF_DECRYPT, &walk);
}
static struct crypto_alg ctr_aes_alg = {
.cra_name = "ctr(aes)",
.cra_driver_name = "ctr-aes-s390",
.cra_priority = 400, /* combo: aes + ctr */
.cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER |
CRYPTO_ALG_NEED_FALLBACK,
.cra_blocksize = 1,
.cra_ctxsize = sizeof(struct s390_aes_ctx),
.cra_type = &crypto_blkcipher_type,
.cra_module = THIS_MODULE,
.cra_init = fallback_init_blk,
.cra_exit = fallback_exit_blk,
.cra_u = {
.blkcipher = {
.min_keysize = AES_MIN_KEY_SIZE,
.max_keysize = AES_MAX_KEY_SIZE,
.ivsize = AES_BLOCK_SIZE,
.setkey = ctr_aes_set_key,
.encrypt = ctr_aes_encrypt,
.decrypt = ctr_aes_decrypt,
}
}
};
static struct crypto_alg *aes_s390_algs_ptr[5];
static int aes_s390_algs_num;
static int aes_s390_register_alg(struct crypto_alg *alg)
{
int ret;
ret = crypto_register_alg(alg);
if (!ret)
aes_s390_algs_ptr[aes_s390_algs_num++] = alg;
return ret;
}
static void aes_s390_fini(void)
{
while (aes_s390_algs_num--)
crypto_unregister_alg(aes_s390_algs_ptr[aes_s390_algs_num]);
if (ctrblk)
free_page((unsigned long) ctrblk);
}
static int __init aes_s390_init(void)
{
int ret;
/* Query available functions for KM, KMC and KMCTR */
cpacf_query(CPACF_KM, &km_functions);
cpacf_query(CPACF_KMC, &kmc_functions);
cpacf_query(CPACF_KMCTR, &kmctr_functions);
if (cpacf_test_func(&km_functions, CPACF_KM_AES_128) ||
cpacf_test_func(&km_functions, CPACF_KM_AES_192) ||
cpacf_test_func(&km_functions, CPACF_KM_AES_256)) {
ret = aes_s390_register_alg(&aes_alg);
if (ret)
goto out_err;
ret = aes_s390_register_alg(&ecb_aes_alg);
if (ret)
goto out_err;
}
if (cpacf_test_func(&kmc_functions, CPACF_KMC_AES_128) ||
cpacf_test_func(&kmc_functions, CPACF_KMC_AES_192) ||
cpacf_test_func(&kmc_functions, CPACF_KMC_AES_256)) {
ret = aes_s390_register_alg(&cbc_aes_alg);
if (ret)
goto out_err;
}
if (cpacf_test_func(&km_functions, CPACF_KM_XTS_128) ||
cpacf_test_func(&km_functions, CPACF_KM_XTS_256)) {
ret = aes_s390_register_alg(&xts_aes_alg);
if (ret)
goto out_err;
}
if (cpacf_test_func(&kmctr_functions, CPACF_KMCTR_AES_128) ||
cpacf_test_func(&kmctr_functions, CPACF_KMCTR_AES_192) ||
cpacf_test_func(&kmctr_functions, CPACF_KMCTR_AES_256)) {
ctrblk = (u8 *) __get_free_page(GFP_KERNEL);
if (!ctrblk) {
ret = -ENOMEM;
goto out_err;
}
ret = aes_s390_register_alg(&ctr_aes_alg);
if (ret)
goto out_err;
}
return 0;
out_err:
aes_s390_fini();
return ret;
}
module_cpu_feature_match(MSA, aes_s390_init);
module_exit(aes_s390_fini);
MODULE_ALIAS_CRYPTO("aes-all");
MODULE_DESCRIPTION("Rijndael (AES) Cipher Algorithm");
MODULE_LICENSE("GPL");