blob: 526c3f40f6a2624dedf3cd45335af2d34c27f713 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0+
/*
* Cryptographic API.
*
* s390 implementation of the AES Cipher Algorithm.
*
* s390 Version:
* Copyright IBM Corp. 2005, 2017
* Author(s): Jan Glauber (jang@de.ibm.com)
* Sebastian Siewior (sebastian@breakpoint.cc> SW-Fallback
* Patrick Steuer <patrick.steuer@de.ibm.com>
* Harald Freudenberger <freude@de.ibm.com>
*
* Derived from "crypto/aes_generic.c"
*/
#define KMSG_COMPONENT "aes_s390"
#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
#include <crypto/aes.h>
#include <crypto/algapi.h>
#include <crypto/ghash.h>
#include <crypto/internal/aead.h>
#include <crypto/internal/cipher.h>
#include <crypto/internal/skcipher.h>
#include <crypto/scatterwalk.h>
#include <linux/err.h>
#include <linux/module.h>
#include <linux/cpufeature.h>
#include <linux/init.h>
#include <linux/mutex.h>
#include <linux/fips.h>
#include <linux/string.h>
#include <crypto/xts.h>
#include <asm/cpacf.h>
static u8 *ctrblk;
static DEFINE_MUTEX(ctrblk_lock);
static cpacf_mask_t km_functions, kmc_functions, kmctr_functions,
kma_functions;
struct s390_aes_ctx {
u8 key[AES_MAX_KEY_SIZE];
int key_len;
unsigned long fc;
union {
struct crypto_skcipher *skcipher;
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;
};
struct gcm_sg_walk {
struct scatter_walk walk;
unsigned int walk_bytes;
u8 *walk_ptr;
unsigned int walk_bytes_remain;
u8 buf[AES_BLOCK_SIZE];
unsigned int buf_bytes;
u8 *ptr;
unsigned int nbytes;
};
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);
sctx->fallback.cip->base.crt_flags &= ~CRYPTO_TFM_REQ_MASK;
sctx->fallback.cip->base.crt_flags |= (tfm->crt_flags &
CRYPTO_TFM_REQ_MASK);
return crypto_cipher_setkey(sctx->fallback.cip, in_key, key_len);
}
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 crypto_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 crypto_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_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 = crypto_aes_encrypt,
.cia_decrypt = crypto_aes_decrypt,
}
}
};
static int setkey_fallback_skcipher(struct crypto_skcipher *tfm, const u8 *key,
unsigned int len)
{
struct s390_aes_ctx *sctx = crypto_skcipher_ctx(tfm);
crypto_skcipher_clear_flags(sctx->fallback.skcipher,
CRYPTO_TFM_REQ_MASK);
crypto_skcipher_set_flags(sctx->fallback.skcipher,
crypto_skcipher_get_flags(tfm) &
CRYPTO_TFM_REQ_MASK);
return crypto_skcipher_setkey(sctx->fallback.skcipher, key, len);
}
static int fallback_skcipher_crypt(struct s390_aes_ctx *sctx,
struct skcipher_request *req,
unsigned long modifier)
{
struct skcipher_request *subreq = skcipher_request_ctx(req);
*subreq = *req;
skcipher_request_set_tfm(subreq, sctx->fallback.skcipher);
return (modifier & CPACF_DECRYPT) ?
crypto_skcipher_decrypt(subreq) :
crypto_skcipher_encrypt(subreq);
}
static int ecb_aes_set_key(struct crypto_skcipher *tfm, const u8 *in_key,
unsigned int key_len)
{
struct s390_aes_ctx *sctx = crypto_skcipher_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_skcipher(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 skcipher_request *req, unsigned long modifier)
{
struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
struct s390_aes_ctx *sctx = crypto_skcipher_ctx(tfm);
struct skcipher_walk walk;
unsigned int nbytes, n;
int ret;
if (unlikely(!sctx->fc))
return fallback_skcipher_crypt(sctx, req, modifier);
ret = skcipher_walk_virt(&walk, req, false);
while ((nbytes = walk.nbytes) != 0) {
/* 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 = skcipher_walk_done(&walk, nbytes - n);
}
return ret;
}
static int ecb_aes_encrypt(struct skcipher_request *req)
{
return ecb_aes_crypt(req, 0);
}
static int ecb_aes_decrypt(struct skcipher_request *req)
{
return ecb_aes_crypt(req, CPACF_DECRYPT);
}
static int fallback_init_skcipher(struct crypto_skcipher *tfm)
{
const char *name = crypto_tfm_alg_name(&tfm->base);
struct s390_aes_ctx *sctx = crypto_skcipher_ctx(tfm);
sctx->fallback.skcipher = crypto_alloc_skcipher(name, 0,
CRYPTO_ALG_NEED_FALLBACK | CRYPTO_ALG_ASYNC);
if (IS_ERR(sctx->fallback.skcipher)) {
pr_err("Allocating AES fallback algorithm %s failed\n",
name);
return PTR_ERR(sctx->fallback.skcipher);
}
crypto_skcipher_set_reqsize(tfm, sizeof(struct skcipher_request) +
crypto_skcipher_reqsize(sctx->fallback.skcipher));
return 0;
}
static void fallback_exit_skcipher(struct crypto_skcipher *tfm)
{
struct s390_aes_ctx *sctx = crypto_skcipher_ctx(tfm);
crypto_free_skcipher(sctx->fallback.skcipher);
}
static struct skcipher_alg ecb_aes_alg = {
.base.cra_name = "ecb(aes)",
.base.cra_driver_name = "ecb-aes-s390",
.base.cra_priority = 401, /* combo: aes + ecb + 1 */
.base.cra_flags = CRYPTO_ALG_NEED_FALLBACK,
.base.cra_blocksize = AES_BLOCK_SIZE,
.base.cra_ctxsize = sizeof(struct s390_aes_ctx),
.base.cra_module = THIS_MODULE,
.init = fallback_init_skcipher,
.exit = fallback_exit_skcipher,
.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_skcipher *tfm, const u8 *in_key,
unsigned int key_len)
{
struct s390_aes_ctx *sctx = crypto_skcipher_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_skcipher(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 skcipher_request *req, unsigned long modifier)
{
struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
struct s390_aes_ctx *sctx = crypto_skcipher_ctx(tfm);
struct skcipher_walk walk;
unsigned int nbytes, n;
int ret;
struct {
u8 iv[AES_BLOCK_SIZE];
u8 key[AES_MAX_KEY_SIZE];
} param;
if (unlikely(!sctx->fc))
return fallback_skcipher_crypt(sctx, req, modifier);
ret = skcipher_walk_virt(&walk, req, false);
if (ret)
return ret;
memcpy(param.iv, walk.iv, AES_BLOCK_SIZE);
memcpy(param.key, sctx->key, sctx->key_len);
while ((nbytes = walk.nbytes) != 0) {
/* 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);
memcpy(walk.iv, param.iv, AES_BLOCK_SIZE);
ret = skcipher_walk_done(&walk, nbytes - n);
}
memzero_explicit(&param, sizeof(param));
return ret;
}
static int cbc_aes_encrypt(struct skcipher_request *req)
{
return cbc_aes_crypt(req, 0);
}
static int cbc_aes_decrypt(struct skcipher_request *req)
{
return cbc_aes_crypt(req, CPACF_DECRYPT);
}
static struct skcipher_alg cbc_aes_alg = {
.base.cra_name = "cbc(aes)",
.base.cra_driver_name = "cbc-aes-s390",
.base.cra_priority = 402, /* ecb-aes-s390 + 1 */
.base.cra_flags = CRYPTO_ALG_NEED_FALLBACK,
.base.cra_blocksize = AES_BLOCK_SIZE,
.base.cra_ctxsize = sizeof(struct s390_aes_ctx),
.base.cra_module = THIS_MODULE,
.init = fallback_init_skcipher,
.exit = fallback_exit_skcipher,
.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_skcipher *tfm, const u8 *key,
unsigned int len)
{
struct s390_xts_ctx *xts_ctx = crypto_skcipher_ctx(tfm);
crypto_skcipher_clear_flags(xts_ctx->fallback, CRYPTO_TFM_REQ_MASK);
crypto_skcipher_set_flags(xts_ctx->fallback,
crypto_skcipher_get_flags(tfm) &
CRYPTO_TFM_REQ_MASK);
return crypto_skcipher_setkey(xts_ctx->fallback, key, len);
}
static int xts_aes_set_key(struct crypto_skcipher *tfm, const u8 *in_key,
unsigned int key_len)
{
struct s390_xts_ctx *xts_ctx = crypto_skcipher_ctx(tfm);
unsigned long fc;
int err;
err = xts_fallback_setkey(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)
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 0;
/* 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 skcipher_request *req, unsigned long modifier)
{
struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
struct s390_xts_ctx *xts_ctx = crypto_skcipher_ctx(tfm);
struct skcipher_walk walk;
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;
if (req->cryptlen < AES_BLOCK_SIZE)
return -EINVAL;
if (unlikely(!xts_ctx->fc || (req->cryptlen % AES_BLOCK_SIZE) != 0)) {
struct skcipher_request *subreq = skcipher_request_ctx(req);
*subreq = *req;
skcipher_request_set_tfm(subreq, xts_ctx->fallback);
return (modifier & CPACF_DECRYPT) ?
crypto_skcipher_decrypt(subreq) :
crypto_skcipher_encrypt(subreq);
}
ret = skcipher_walk_virt(&walk, req, false);
if (ret)
return ret;
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) != 0) {
/* 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 = skcipher_walk_done(&walk, nbytes - n);
}
memzero_explicit(&pcc_param, sizeof(pcc_param));
memzero_explicit(&xts_param, sizeof(xts_param));
return ret;
}
static int xts_aes_encrypt(struct skcipher_request *req)
{
return xts_aes_crypt(req, 0);
}
static int xts_aes_decrypt(struct skcipher_request *req)
{
return xts_aes_crypt(req, CPACF_DECRYPT);
}
static int xts_fallback_init(struct crypto_skcipher *tfm)
{
const char *name = crypto_tfm_alg_name(&tfm->base);
struct s390_xts_ctx *xts_ctx = crypto_skcipher_ctx(tfm);
xts_ctx->fallback = crypto_alloc_skcipher(name, 0,
CRYPTO_ALG_NEED_FALLBACK | CRYPTO_ALG_ASYNC);
if (IS_ERR(xts_ctx->fallback)) {
pr_err("Allocating XTS fallback algorithm %s failed\n",
name);
return PTR_ERR(xts_ctx->fallback);
}
crypto_skcipher_set_reqsize(tfm, sizeof(struct skcipher_request) +
crypto_skcipher_reqsize(xts_ctx->fallback));
return 0;
}
static void xts_fallback_exit(struct crypto_skcipher *tfm)
{
struct s390_xts_ctx *xts_ctx = crypto_skcipher_ctx(tfm);
crypto_free_skcipher(xts_ctx->fallback);
}
static struct skcipher_alg xts_aes_alg = {
.base.cra_name = "xts(aes)",
.base.cra_driver_name = "xts-aes-s390",
.base.cra_priority = 402, /* ecb-aes-s390 + 1 */
.base.cra_flags = CRYPTO_ALG_NEED_FALLBACK,
.base.cra_blocksize = AES_BLOCK_SIZE,
.base.cra_ctxsize = sizeof(struct s390_xts_ctx),
.base.cra_module = THIS_MODULE,
.init = xts_fallback_init,
.exit = xts_fallback_exit,
.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_skcipher *tfm, const u8 *in_key,
unsigned int key_len)
{
struct s390_aes_ctx *sctx = crypto_skcipher_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_skcipher(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 skcipher_request *req)
{
struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
struct s390_aes_ctx *sctx = crypto_skcipher_ctx(tfm);
u8 buf[AES_BLOCK_SIZE], *ctrptr;
struct skcipher_walk walk;
unsigned int n, nbytes;
int ret, locked;
if (unlikely(!sctx->fc))
return fallback_skcipher_crypt(sctx, req, 0);
locked = mutex_trylock(&ctrblk_lock);
ret = skcipher_walk_virt(&walk, req, false);
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, 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 = skcipher_walk_done(&walk, nbytes - n);
}
if (locked)
mutex_unlock(&ctrblk_lock);
/*
* final block may be < AES_BLOCK_SIZE, copy only nbytes
*/
if (nbytes) {
cpacf_kmctr(sctx->fc, 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 = skcipher_walk_done(&walk, 0);
}
return ret;
}
static struct skcipher_alg ctr_aes_alg = {
.base.cra_name = "ctr(aes)",
.base.cra_driver_name = "ctr-aes-s390",
.base.cra_priority = 402, /* ecb-aes-s390 + 1 */
.base.cra_flags = CRYPTO_ALG_NEED_FALLBACK,
.base.cra_blocksize = 1,
.base.cra_ctxsize = sizeof(struct s390_aes_ctx),
.base.cra_module = THIS_MODULE,
.init = fallback_init_skcipher,
.exit = fallback_exit_skcipher,
.min_keysize = AES_MIN_KEY_SIZE,
.max_keysize = AES_MAX_KEY_SIZE,
.ivsize = AES_BLOCK_SIZE,
.setkey = ctr_aes_set_key,
.encrypt = ctr_aes_crypt,
.decrypt = ctr_aes_crypt,
.chunksize = AES_BLOCK_SIZE,
};
static int gcm_aes_setkey(struct crypto_aead *tfm, const u8 *key,
unsigned int keylen)
{
struct s390_aes_ctx *ctx = crypto_aead_ctx(tfm);
switch (keylen) {
case AES_KEYSIZE_128:
ctx->fc = CPACF_KMA_GCM_AES_128;
break;
case AES_KEYSIZE_192:
ctx->fc = CPACF_KMA_GCM_AES_192;
break;
case AES_KEYSIZE_256:
ctx->fc = CPACF_KMA_GCM_AES_256;
break;
default:
return -EINVAL;
}
memcpy(ctx->key, key, keylen);
ctx->key_len = keylen;
return 0;
}
static int gcm_aes_setauthsize(struct crypto_aead *tfm, unsigned int authsize)
{
switch (authsize) {
case 4:
case 8:
case 12:
case 13:
case 14:
case 15:
case 16:
break;
default:
return -EINVAL;
}
return 0;
}
static void gcm_walk_start(struct gcm_sg_walk *gw, struct scatterlist *sg,
unsigned int len)
{
memset(gw, 0, sizeof(*gw));
gw->walk_bytes_remain = len;
scatterwalk_start(&gw->walk, sg);
}
static inline unsigned int _gcm_sg_clamp_and_map(struct gcm_sg_walk *gw)
{
struct scatterlist *nextsg;
gw->walk_bytes = scatterwalk_clamp(&gw->walk, gw->walk_bytes_remain);
while (!gw->walk_bytes) {
nextsg = sg_next(gw->walk.sg);
if (!nextsg)
return 0;
scatterwalk_start(&gw->walk, nextsg);
gw->walk_bytes = scatterwalk_clamp(&gw->walk,
gw->walk_bytes_remain);
}
gw->walk_ptr = scatterwalk_map(&gw->walk);
return gw->walk_bytes;
}
static inline void _gcm_sg_unmap_and_advance(struct gcm_sg_walk *gw,
unsigned int nbytes)
{
gw->walk_bytes_remain -= nbytes;
scatterwalk_unmap(gw->walk_ptr);
scatterwalk_advance(&gw->walk, nbytes);
scatterwalk_done(&gw->walk, 0, gw->walk_bytes_remain);
gw->walk_ptr = NULL;
}
static int gcm_in_walk_go(struct gcm_sg_walk *gw, unsigned int minbytesneeded)
{
int n;
if (gw->buf_bytes && gw->buf_bytes >= minbytesneeded) {
gw->ptr = gw->buf;
gw->nbytes = gw->buf_bytes;
goto out;
}
if (gw->walk_bytes_remain == 0) {
gw->ptr = NULL;
gw->nbytes = 0;
goto out;
}
if (!_gcm_sg_clamp_and_map(gw)) {
gw->ptr = NULL;
gw->nbytes = 0;
goto out;
}
if (!gw->buf_bytes && gw->walk_bytes >= minbytesneeded) {
gw->ptr = gw->walk_ptr;
gw->nbytes = gw->walk_bytes;
goto out;
}
while (1) {
n = min(gw->walk_bytes, AES_BLOCK_SIZE - gw->buf_bytes);
memcpy(gw->buf + gw->buf_bytes, gw->walk_ptr, n);
gw->buf_bytes += n;
_gcm_sg_unmap_and_advance(gw, n);
if (gw->buf_bytes >= minbytesneeded) {
gw->ptr = gw->buf;
gw->nbytes = gw->buf_bytes;
goto out;
}
if (!_gcm_sg_clamp_and_map(gw)) {
gw->ptr = NULL;
gw->nbytes = 0;
goto out;
}
}
out:
return gw->nbytes;
}
static int gcm_out_walk_go(struct gcm_sg_walk *gw, unsigned int minbytesneeded)
{
if (gw->walk_bytes_remain == 0) {
gw->ptr = NULL;
gw->nbytes = 0;
goto out;
}
if (!_gcm_sg_clamp_and_map(gw)) {
gw->ptr = NULL;
gw->nbytes = 0;
goto out;
}
if (gw->walk_bytes >= minbytesneeded) {
gw->ptr = gw->walk_ptr;
gw->nbytes = gw->walk_bytes;
goto out;
}
scatterwalk_unmap(gw->walk_ptr);
gw->walk_ptr = NULL;
gw->ptr = gw->buf;
gw->nbytes = sizeof(gw->buf);
out:
return gw->nbytes;
}
static int gcm_in_walk_done(struct gcm_sg_walk *gw, unsigned int bytesdone)
{
if (gw->ptr == NULL)
return 0;
if (gw->ptr == gw->buf) {
int n = gw->buf_bytes - bytesdone;
if (n > 0) {
memmove(gw->buf, gw->buf + bytesdone, n);
gw->buf_bytes = n;
} else
gw->buf_bytes = 0;
} else
_gcm_sg_unmap_and_advance(gw, bytesdone);
return bytesdone;
}
static int gcm_out_walk_done(struct gcm_sg_walk *gw, unsigned int bytesdone)
{
int i, n;
if (gw->ptr == NULL)
return 0;
if (gw->ptr == gw->buf) {
for (i = 0; i < bytesdone; i += n) {
if (!_gcm_sg_clamp_and_map(gw))
return i;
n = min(gw->walk_bytes, bytesdone - i);
memcpy(gw->walk_ptr, gw->buf + i, n);
_gcm_sg_unmap_and_advance(gw, n);
}
} else
_gcm_sg_unmap_and_advance(gw, bytesdone);
return bytesdone;
}
static int gcm_aes_crypt(struct aead_request *req, unsigned int flags)
{
struct crypto_aead *tfm = crypto_aead_reqtfm(req);
struct s390_aes_ctx *ctx = crypto_aead_ctx(tfm);
unsigned int ivsize = crypto_aead_ivsize(tfm);
unsigned int taglen = crypto_aead_authsize(tfm);
unsigned int aadlen = req->assoclen;
unsigned int pclen = req->cryptlen;
int ret = 0;
unsigned int n, len, in_bytes, out_bytes,
min_bytes, bytes, aad_bytes, pc_bytes;
struct gcm_sg_walk gw_in, gw_out;
u8 tag[GHASH_DIGEST_SIZE];
struct {
u32 _[3]; /* reserved */
u32 cv; /* Counter Value */
u8 t[GHASH_DIGEST_SIZE];/* Tag */
u8 h[AES_BLOCK_SIZE]; /* Hash-subkey */
u64 taadl; /* Total AAD Length */
u64 tpcl; /* Total Plain-/Cipher-text Length */
u8 j0[GHASH_BLOCK_SIZE];/* initial counter value */
u8 k[AES_MAX_KEY_SIZE]; /* Key */
} param;
/*
* encrypt
* req->src: aad||plaintext
* req->dst: aad||ciphertext||tag
* decrypt
* req->src: aad||ciphertext||tag
* req->dst: aad||plaintext, return 0 or -EBADMSG
* aad, plaintext and ciphertext may be empty.
*/
if (flags & CPACF_DECRYPT)
pclen -= taglen;
len = aadlen + pclen;
memset(&param, 0, sizeof(param));
param.cv = 1;
param.taadl = aadlen * 8;
param.tpcl = pclen * 8;
memcpy(param.j0, req->iv, ivsize);
*(u32 *)(param.j0 + ivsize) = 1;
memcpy(param.k, ctx->key, ctx->key_len);
gcm_walk_start(&gw_in, req->src, len);
gcm_walk_start(&gw_out, req->dst, len);
do {
min_bytes = min_t(unsigned int,
aadlen > 0 ? aadlen : pclen, AES_BLOCK_SIZE);
in_bytes = gcm_in_walk_go(&gw_in, min_bytes);
out_bytes = gcm_out_walk_go(&gw_out, min_bytes);
bytes = min(in_bytes, out_bytes);
if (aadlen + pclen <= bytes) {
aad_bytes = aadlen;
pc_bytes = pclen;
flags |= CPACF_KMA_LAAD | CPACF_KMA_LPC;
} else {
if (aadlen <= bytes) {
aad_bytes = aadlen;
pc_bytes = (bytes - aadlen) &
~(AES_BLOCK_SIZE - 1);
flags |= CPACF_KMA_LAAD;
} else {
aad_bytes = bytes & ~(AES_BLOCK_SIZE - 1);
pc_bytes = 0;
}
}
if (aad_bytes > 0)
memcpy(gw_out.ptr, gw_in.ptr, aad_bytes);
cpacf_kma(ctx->fc | flags, &param,
gw_out.ptr + aad_bytes,
gw_in.ptr + aad_bytes, pc_bytes,
gw_in.ptr, aad_bytes);
n = aad_bytes + pc_bytes;
if (gcm_in_walk_done(&gw_in, n) != n)
return -ENOMEM;
if (gcm_out_walk_done(&gw_out, n) != n)
return -ENOMEM;
aadlen -= aad_bytes;
pclen -= pc_bytes;
} while (aadlen + pclen > 0);
if (flags & CPACF_DECRYPT) {
scatterwalk_map_and_copy(tag, req->src, len, taglen, 0);
if (crypto_memneq(tag, param.t, taglen))
ret = -EBADMSG;
} else
scatterwalk_map_and_copy(param.t, req->dst, len, taglen, 1);
memzero_explicit(&param, sizeof(param));
return ret;
}
static int gcm_aes_encrypt(struct aead_request *req)
{
return gcm_aes_crypt(req, CPACF_ENCRYPT);
}
static int gcm_aes_decrypt(struct aead_request *req)
{
return gcm_aes_crypt(req, CPACF_DECRYPT);
}
static struct aead_alg gcm_aes_aead = {
.setkey = gcm_aes_setkey,
.setauthsize = gcm_aes_setauthsize,
.encrypt = gcm_aes_encrypt,
.decrypt = gcm_aes_decrypt,
.ivsize = GHASH_BLOCK_SIZE - sizeof(u32),
.maxauthsize = GHASH_DIGEST_SIZE,
.chunksize = AES_BLOCK_SIZE,
.base = {
.cra_blocksize = 1,
.cra_ctxsize = sizeof(struct s390_aes_ctx),
.cra_priority = 900,
.cra_name = "gcm(aes)",
.cra_driver_name = "gcm-aes-s390",
.cra_module = THIS_MODULE,
},
};
static struct crypto_alg *aes_s390_alg;
static struct skcipher_alg *aes_s390_skcipher_algs[4];
static int aes_s390_skciphers_num;
static struct aead_alg *aes_s390_aead_alg;
static int aes_s390_register_skcipher(struct skcipher_alg *alg)
{
int ret;
ret = crypto_register_skcipher(alg);
if (!ret)
aes_s390_skcipher_algs[aes_s390_skciphers_num++] = alg;
return ret;
}
static void aes_s390_fini(void)
{
if (aes_s390_alg)
crypto_unregister_alg(aes_s390_alg);
while (aes_s390_skciphers_num--)
crypto_unregister_skcipher(aes_s390_skcipher_algs[aes_s390_skciphers_num]);
if (ctrblk)
free_page((unsigned long) ctrblk);
if (aes_s390_aead_alg)
crypto_unregister_aead(aes_s390_aead_alg);
}
static int __init aes_s390_init(void)
{
int ret;
/* Query available functions for KM, KMC, KMCTR and KMA */
cpacf_query(CPACF_KM, &km_functions);
cpacf_query(CPACF_KMC, &kmc_functions);
cpacf_query(CPACF_KMCTR, &kmctr_functions);
cpacf_query(CPACF_KMA, &kma_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 = crypto_register_alg(&aes_alg);
if (ret)
goto out_err;
aes_s390_alg = &aes_alg;
ret = aes_s390_register_skcipher(&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_skcipher(&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_skcipher(&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_skcipher(&ctr_aes_alg);
if (ret)
goto out_err;
}
if (cpacf_test_func(&kma_functions, CPACF_KMA_GCM_AES_128) ||
cpacf_test_func(&kma_functions, CPACF_KMA_GCM_AES_192) ||
cpacf_test_func(&kma_functions, CPACF_KMA_GCM_AES_256)) {
ret = crypto_register_aead(&gcm_aes_aead);
if (ret)
goto out_err;
aes_s390_aead_alg = &gcm_aes_aead;
}
return 0;
out_err:
aes_s390_fini();
return ret;
}
module_cpu_feature_match(S390_CPU_FEATURE_MSA, aes_s390_init);
module_exit(aes_s390_fini);
MODULE_ALIAS_CRYPTO("aes-all");
MODULE_DESCRIPTION("Rijndael (AES) Cipher Algorithm");
MODULE_LICENSE("GPL");
MODULE_IMPORT_NS(CRYPTO_INTERNAL);