kernel-hacking-2024-linux-s.../arch/s390/crypto/des_s390.c
Martin Schwidefsky 69c0e360f9 s390/crypto: cpacf function detection
The CPACF code makes some assumptions about the availablity of hardware
support. E.g. if the machine supports KM(AES-256) without chaining it is
assumed that KMC(AES-256) with chaining is available as well. For the
existing CPUs this is true but the architecturally correct way is to
check each CPACF functions on its own. This is what the query function
of each instructions is all about.

Reviewed-by: Harald Freudenberger <freude@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-08-29 11:05:09 +02:00

623 lines
16 KiB
C

/*
* Cryptographic API.
*
* s390 implementation of the DES Cipher Algorithm.
*
* Copyright IBM Corp. 2003, 2011
* Author(s): Thomas Spatzier
* Jan Glauber (jan.glauber@de.ibm.com)
*
* 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.
*
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/cpufeature.h>
#include <linux/crypto.h>
#include <crypto/algapi.h>
#include <crypto/des.h>
#include <asm/cpacf.h>
#define DES3_KEY_SIZE (3 * DES_KEY_SIZE)
static u8 *ctrblk;
static DEFINE_SPINLOCK(ctrblk_lock);
static cpacf_mask_t km_functions, kmc_functions, kmctr_functions;
struct s390_des_ctx {
u8 iv[DES_BLOCK_SIZE];
u8 key[DES3_KEY_SIZE];
};
static int des_setkey(struct crypto_tfm *tfm, const u8 *key,
unsigned int key_len)
{
struct s390_des_ctx *ctx = crypto_tfm_ctx(tfm);
u32 tmp[DES_EXPKEY_WORDS];
/* check for weak keys */
if (!des_ekey(tmp, key) &&
(tfm->crt_flags & CRYPTO_TFM_REQ_WEAK_KEY)) {
tfm->crt_flags |= CRYPTO_TFM_RES_WEAK_KEY;
return -EINVAL;
}
memcpy(ctx->key, key, key_len);
return 0;
}
static void des_encrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in)
{
struct s390_des_ctx *ctx = crypto_tfm_ctx(tfm);
cpacf_km(CPACF_KM_DEA, ctx->key, out, in, DES_BLOCK_SIZE);
}
static void des_decrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in)
{
struct s390_des_ctx *ctx = crypto_tfm_ctx(tfm);
cpacf_km(CPACF_KM_DEA | CPACF_DECRYPT,
ctx->key, out, in, DES_BLOCK_SIZE);
}
static struct crypto_alg des_alg = {
.cra_name = "des",
.cra_driver_name = "des-s390",
.cra_priority = 300,
.cra_flags = CRYPTO_ALG_TYPE_CIPHER,
.cra_blocksize = DES_BLOCK_SIZE,
.cra_ctxsize = sizeof(struct s390_des_ctx),
.cra_module = THIS_MODULE,
.cra_u = {
.cipher = {
.cia_min_keysize = DES_KEY_SIZE,
.cia_max_keysize = DES_KEY_SIZE,
.cia_setkey = des_setkey,
.cia_encrypt = des_encrypt,
.cia_decrypt = des_decrypt,
}
}
};
static int ecb_desall_crypt(struct blkcipher_desc *desc, long func,
u8 *key, struct blkcipher_walk *walk)
{
int ret = blkcipher_walk_virt(desc, walk);
unsigned int nbytes;
while ((nbytes = walk->nbytes)) {
/* only use complete blocks */
unsigned int n = nbytes & ~(DES_BLOCK_SIZE - 1);
u8 *out = walk->dst.virt.addr;
u8 *in = walk->src.virt.addr;
cpacf_km(func, key, out, in, n);
nbytes &= DES_BLOCK_SIZE - 1;
ret = blkcipher_walk_done(desc, walk, nbytes);
}
return ret;
}
static int cbc_desall_crypt(struct blkcipher_desc *desc, long func,
struct blkcipher_walk *walk)
{
struct s390_des_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
int ret = blkcipher_walk_virt(desc, walk);
unsigned int nbytes = walk->nbytes;
struct {
u8 iv[DES_BLOCK_SIZE];
u8 key[DES3_KEY_SIZE];
} param;
if (!nbytes)
goto out;
memcpy(param.iv, walk->iv, DES_BLOCK_SIZE);
memcpy(param.key, ctx->key, DES3_KEY_SIZE);
do {
/* only use complete blocks */
unsigned int n = nbytes & ~(DES_BLOCK_SIZE - 1);
u8 *out = walk->dst.virt.addr;
u8 *in = walk->src.virt.addr;
cpacf_kmc(func, &param, out, in, n);
nbytes &= DES_BLOCK_SIZE - 1;
ret = blkcipher_walk_done(desc, walk, nbytes);
} while ((nbytes = walk->nbytes));
memcpy(walk->iv, param.iv, DES_BLOCK_SIZE);
out:
return ret;
}
static int ecb_des_encrypt(struct blkcipher_desc *desc,
struct scatterlist *dst, struct scatterlist *src,
unsigned int nbytes)
{
struct s390_des_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
struct blkcipher_walk walk;
blkcipher_walk_init(&walk, dst, src, nbytes);
return ecb_desall_crypt(desc, CPACF_KM_DEA, ctx->key, &walk);
}
static int ecb_des_decrypt(struct blkcipher_desc *desc,
struct scatterlist *dst, struct scatterlist *src,
unsigned int nbytes)
{
struct s390_des_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
struct blkcipher_walk walk;
blkcipher_walk_init(&walk, dst, src, nbytes);
return ecb_desall_crypt(desc, CPACF_KM_DEA | CPACF_DECRYPT,
ctx->key, &walk);
}
static struct crypto_alg ecb_des_alg = {
.cra_name = "ecb(des)",
.cra_driver_name = "ecb-des-s390",
.cra_priority = 400, /* combo: des + ecb */
.cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER,
.cra_blocksize = DES_BLOCK_SIZE,
.cra_ctxsize = sizeof(struct s390_des_ctx),
.cra_type = &crypto_blkcipher_type,
.cra_module = THIS_MODULE,
.cra_u = {
.blkcipher = {
.min_keysize = DES_KEY_SIZE,
.max_keysize = DES_KEY_SIZE,
.setkey = des_setkey,
.encrypt = ecb_des_encrypt,
.decrypt = ecb_des_decrypt,
}
}
};
static int cbc_des_encrypt(struct blkcipher_desc *desc,
struct scatterlist *dst, struct scatterlist *src,
unsigned int nbytes)
{
struct blkcipher_walk walk;
blkcipher_walk_init(&walk, dst, src, nbytes);
return cbc_desall_crypt(desc, CPACF_KMC_DEA, &walk);
}
static int cbc_des_decrypt(struct blkcipher_desc *desc,
struct scatterlist *dst, struct scatterlist *src,
unsigned int nbytes)
{
struct blkcipher_walk walk;
blkcipher_walk_init(&walk, dst, src, nbytes);
return cbc_desall_crypt(desc, CPACF_KMC_DEA | CPACF_DECRYPT, &walk);
}
static struct crypto_alg cbc_des_alg = {
.cra_name = "cbc(des)",
.cra_driver_name = "cbc-des-s390",
.cra_priority = 400, /* combo: des + cbc */
.cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER,
.cra_blocksize = DES_BLOCK_SIZE,
.cra_ctxsize = sizeof(struct s390_des_ctx),
.cra_type = &crypto_blkcipher_type,
.cra_module = THIS_MODULE,
.cra_u = {
.blkcipher = {
.min_keysize = DES_KEY_SIZE,
.max_keysize = DES_KEY_SIZE,
.ivsize = DES_BLOCK_SIZE,
.setkey = des_setkey,
.encrypt = cbc_des_encrypt,
.decrypt = cbc_des_decrypt,
}
}
};
/*
* RFC2451:
*
* For DES-EDE3, there is no known need to reject weak or
* complementation keys. Any weakness is obviated by the use of
* multiple keys.
*
* However, if the first two or last two independent 64-bit keys are
* equal (k1 == k2 or k2 == k3), then the DES3 operation is simply the
* same as DES. Implementers MUST reject keys that exhibit this
* property.
*
*/
static int des3_setkey(struct crypto_tfm *tfm, const u8 *key,
unsigned int key_len)
{
struct s390_des_ctx *ctx = crypto_tfm_ctx(tfm);
if (!(crypto_memneq(key, &key[DES_KEY_SIZE], DES_KEY_SIZE) &&
crypto_memneq(&key[DES_KEY_SIZE], &key[DES_KEY_SIZE * 2],
DES_KEY_SIZE)) &&
(tfm->crt_flags & CRYPTO_TFM_REQ_WEAK_KEY)) {
tfm->crt_flags |= CRYPTO_TFM_RES_WEAK_KEY;
return -EINVAL;
}
memcpy(ctx->key, key, key_len);
return 0;
}
static void des3_encrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
{
struct s390_des_ctx *ctx = crypto_tfm_ctx(tfm);
cpacf_km(CPACF_KM_TDEA_192, ctx->key, dst, src, DES_BLOCK_SIZE);
}
static void des3_decrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
{
struct s390_des_ctx *ctx = crypto_tfm_ctx(tfm);
cpacf_km(CPACF_KM_TDEA_192 | CPACF_DECRYPT,
ctx->key, dst, src, DES_BLOCK_SIZE);
}
static struct crypto_alg des3_alg = {
.cra_name = "des3_ede",
.cra_driver_name = "des3_ede-s390",
.cra_priority = 300,
.cra_flags = CRYPTO_ALG_TYPE_CIPHER,
.cra_blocksize = DES_BLOCK_SIZE,
.cra_ctxsize = sizeof(struct s390_des_ctx),
.cra_module = THIS_MODULE,
.cra_u = {
.cipher = {
.cia_min_keysize = DES3_KEY_SIZE,
.cia_max_keysize = DES3_KEY_SIZE,
.cia_setkey = des3_setkey,
.cia_encrypt = des3_encrypt,
.cia_decrypt = des3_decrypt,
}
}
};
static int ecb_des3_encrypt(struct blkcipher_desc *desc,
struct scatterlist *dst, struct scatterlist *src,
unsigned int nbytes)
{
struct s390_des_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
struct blkcipher_walk walk;
blkcipher_walk_init(&walk, dst, src, nbytes);
return ecb_desall_crypt(desc, CPACF_KM_TDEA_192, ctx->key, &walk);
}
static int ecb_des3_decrypt(struct blkcipher_desc *desc,
struct scatterlist *dst, struct scatterlist *src,
unsigned int nbytes)
{
struct s390_des_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
struct blkcipher_walk walk;
blkcipher_walk_init(&walk, dst, src, nbytes);
return ecb_desall_crypt(desc, CPACF_KM_TDEA_192 | CPACF_DECRYPT,
ctx->key, &walk);
}
static struct crypto_alg ecb_des3_alg = {
.cra_name = "ecb(des3_ede)",
.cra_driver_name = "ecb-des3_ede-s390",
.cra_priority = 400, /* combo: des3 + ecb */
.cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER,
.cra_blocksize = DES_BLOCK_SIZE,
.cra_ctxsize = sizeof(struct s390_des_ctx),
.cra_type = &crypto_blkcipher_type,
.cra_module = THIS_MODULE,
.cra_u = {
.blkcipher = {
.min_keysize = DES3_KEY_SIZE,
.max_keysize = DES3_KEY_SIZE,
.setkey = des3_setkey,
.encrypt = ecb_des3_encrypt,
.decrypt = ecb_des3_decrypt,
}
}
};
static int cbc_des3_encrypt(struct blkcipher_desc *desc,
struct scatterlist *dst, struct scatterlist *src,
unsigned int nbytes)
{
struct blkcipher_walk walk;
blkcipher_walk_init(&walk, dst, src, nbytes);
return cbc_desall_crypt(desc, CPACF_KMC_TDEA_192, &walk);
}
static int cbc_des3_decrypt(struct blkcipher_desc *desc,
struct scatterlist *dst, struct scatterlist *src,
unsigned int nbytes)
{
struct blkcipher_walk walk;
blkcipher_walk_init(&walk, dst, src, nbytes);
return cbc_desall_crypt(desc, CPACF_KMC_TDEA_192 | CPACF_DECRYPT,
&walk);
}
static struct crypto_alg cbc_des3_alg = {
.cra_name = "cbc(des3_ede)",
.cra_driver_name = "cbc-des3_ede-s390",
.cra_priority = 400, /* combo: des3 + cbc */
.cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER,
.cra_blocksize = DES_BLOCK_SIZE,
.cra_ctxsize = sizeof(struct s390_des_ctx),
.cra_type = &crypto_blkcipher_type,
.cra_module = THIS_MODULE,
.cra_u = {
.blkcipher = {
.min_keysize = DES3_KEY_SIZE,
.max_keysize = DES3_KEY_SIZE,
.ivsize = DES_BLOCK_SIZE,
.setkey = des3_setkey,
.encrypt = cbc_des3_encrypt,
.decrypt = cbc_des3_decrypt,
}
}
};
static unsigned int __ctrblk_init(u8 *ctrptr, unsigned int nbytes)
{
unsigned int i, n;
/* align to block size, max. PAGE_SIZE */
n = (nbytes > PAGE_SIZE) ? PAGE_SIZE : nbytes & ~(DES_BLOCK_SIZE - 1);
for (i = DES_BLOCK_SIZE; i < n; i += DES_BLOCK_SIZE) {
memcpy(ctrptr + i, ctrptr + i - DES_BLOCK_SIZE, DES_BLOCK_SIZE);
crypto_inc(ctrptr + i, DES_BLOCK_SIZE);
}
return n;
}
static int ctr_desall_crypt(struct blkcipher_desc *desc, long func,
struct s390_des_ctx *ctx,
struct blkcipher_walk *walk)
{
int ret = blkcipher_walk_virt_block(desc, walk, DES_BLOCK_SIZE);
unsigned int n, nbytes;
u8 buf[DES_BLOCK_SIZE], ctrbuf[DES_BLOCK_SIZE];
u8 *out, *in, *ctrptr = ctrbuf;
if (!walk->nbytes)
return ret;
if (spin_trylock(&ctrblk_lock))
ctrptr = ctrblk;
memcpy(ctrptr, walk->iv, DES_BLOCK_SIZE);
while ((nbytes = walk->nbytes) >= DES_BLOCK_SIZE) {
out = walk->dst.virt.addr;
in = walk->src.virt.addr;
while (nbytes >= DES_BLOCK_SIZE) {
if (ctrptr == ctrblk)
n = __ctrblk_init(ctrptr, nbytes);
else
n = DES_BLOCK_SIZE;
cpacf_kmctr(func, ctx->key, out, in, n, ctrptr);
if (n > DES_BLOCK_SIZE)
memcpy(ctrptr, ctrptr + n - DES_BLOCK_SIZE,
DES_BLOCK_SIZE);
crypto_inc(ctrptr, DES_BLOCK_SIZE);
out += n;
in += n;
nbytes -= n;
}
ret = blkcipher_walk_done(desc, walk, nbytes);
}
if (ctrptr == ctrblk) {
if (nbytes)
memcpy(ctrbuf, ctrptr, DES_BLOCK_SIZE);
else
memcpy(walk->iv, ctrptr, DES_BLOCK_SIZE);
spin_unlock(&ctrblk_lock);
} else {
if (!nbytes)
memcpy(walk->iv, ctrptr, DES_BLOCK_SIZE);
}
/* final block may be < DES_BLOCK_SIZE, copy only nbytes */
if (nbytes) {
out = walk->dst.virt.addr;
in = walk->src.virt.addr;
cpacf_kmctr(func, ctx->key, buf, in, DES_BLOCK_SIZE, ctrbuf);
memcpy(out, buf, nbytes);
crypto_inc(ctrbuf, DES_BLOCK_SIZE);
ret = blkcipher_walk_done(desc, walk, 0);
memcpy(walk->iv, ctrbuf, DES_BLOCK_SIZE);
}
return ret;
}
static int ctr_des_encrypt(struct blkcipher_desc *desc,
struct scatterlist *dst, struct scatterlist *src,
unsigned int nbytes)
{
struct s390_des_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
struct blkcipher_walk walk;
blkcipher_walk_init(&walk, dst, src, nbytes);
return ctr_desall_crypt(desc, CPACF_KMCTR_DEA, ctx, &walk);
}
static int ctr_des_decrypt(struct blkcipher_desc *desc,
struct scatterlist *dst, struct scatterlist *src,
unsigned int nbytes)
{
struct s390_des_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
struct blkcipher_walk walk;
blkcipher_walk_init(&walk, dst, src, nbytes);
return ctr_desall_crypt(desc, CPACF_KMCTR_DEA | CPACF_DECRYPT,
ctx, &walk);
}
static struct crypto_alg ctr_des_alg = {
.cra_name = "ctr(des)",
.cra_driver_name = "ctr-des-s390",
.cra_priority = 400, /* combo: des + ctr */
.cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER,
.cra_blocksize = 1,
.cra_ctxsize = sizeof(struct s390_des_ctx),
.cra_type = &crypto_blkcipher_type,
.cra_module = THIS_MODULE,
.cra_u = {
.blkcipher = {
.min_keysize = DES_KEY_SIZE,
.max_keysize = DES_KEY_SIZE,
.ivsize = DES_BLOCK_SIZE,
.setkey = des_setkey,
.encrypt = ctr_des_encrypt,
.decrypt = ctr_des_decrypt,
}
}
};
static int ctr_des3_encrypt(struct blkcipher_desc *desc,
struct scatterlist *dst, struct scatterlist *src,
unsigned int nbytes)
{
struct s390_des_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
struct blkcipher_walk walk;
blkcipher_walk_init(&walk, dst, src, nbytes);
return ctr_desall_crypt(desc, CPACF_KMCTR_TDEA_192, ctx, &walk);
}
static int ctr_des3_decrypt(struct blkcipher_desc *desc,
struct scatterlist *dst, struct scatterlist *src,
unsigned int nbytes)
{
struct s390_des_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
struct blkcipher_walk walk;
blkcipher_walk_init(&walk, dst, src, nbytes);
return ctr_desall_crypt(desc, CPACF_KMCTR_TDEA_192 | CPACF_DECRYPT,
ctx, &walk);
}
static struct crypto_alg ctr_des3_alg = {
.cra_name = "ctr(des3_ede)",
.cra_driver_name = "ctr-des3_ede-s390",
.cra_priority = 400, /* combo: des3 + ede */
.cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER,
.cra_blocksize = 1,
.cra_ctxsize = sizeof(struct s390_des_ctx),
.cra_type = &crypto_blkcipher_type,
.cra_module = THIS_MODULE,
.cra_u = {
.blkcipher = {
.min_keysize = DES3_KEY_SIZE,
.max_keysize = DES3_KEY_SIZE,
.ivsize = DES_BLOCK_SIZE,
.setkey = des3_setkey,
.encrypt = ctr_des3_encrypt,
.decrypt = ctr_des3_decrypt,
}
}
};
static struct crypto_alg *des_s390_algs_ptr[8];
static int des_s390_algs_num;
static int des_s390_register_alg(struct crypto_alg *alg)
{
int ret;
ret = crypto_register_alg(alg);
if (!ret)
des_s390_algs_ptr[des_s390_algs_num++] = alg;
return ret;
}
static void des_s390_exit(void)
{
while (des_s390_algs_num--)
crypto_unregister_alg(des_s390_algs_ptr[des_s390_algs_num]);
if (ctrblk)
free_page((unsigned long) ctrblk);
}
static int __init des_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_DEA)) {
ret = des_s390_register_alg(&des_alg);
if (ret)
goto out_err;
ret = des_s390_register_alg(&ecb_des_alg);
if (ret)
goto out_err;
}
if (cpacf_test_func(&kmc_functions, CPACF_KMC_DEA)) {
ret = des_s390_register_alg(&cbc_des_alg);
if (ret)
goto out_err;
}
if (cpacf_test_func(&km_functions, CPACF_KM_TDEA_192)) {
ret = des_s390_register_alg(&des3_alg);
if (ret)
goto out_err;
ret = des_s390_register_alg(&ecb_des3_alg);
if (ret)
goto out_err;
}
if (cpacf_test_func(&kmc_functions, CPACF_KMC_TDEA_192)) {
ret = des_s390_register_alg(&cbc_des3_alg);
if (ret)
goto out_err;
}
if (cpacf_test_func(&kmctr_functions, CPACF_KMCTR_DEA) ||
cpacf_test_func(&kmctr_functions, CPACF_KMCTR_TDEA_192)) {
ctrblk = (u8 *) __get_free_page(GFP_KERNEL);
if (!ctrblk) {
ret = -ENOMEM;
goto out_err;
}
}
if (cpacf_test_func(&kmctr_functions, CPACF_KMCTR_DEA)) {
ret = des_s390_register_alg(&ctr_des_alg);
if (ret)
goto out_err;
}
if (cpacf_test_func(&kmctr_functions, CPACF_KMCTR_TDEA_192)) {
ret = des_s390_register_alg(&ctr_des3_alg);
if (ret)
goto out_err;
}
return 0;
out_err:
des_s390_exit();
return ret;
}
module_cpu_feature_match(MSA, des_s390_init);
module_exit(des_s390_exit);
MODULE_ALIAS_CRYPTO("des");
MODULE_ALIAS_CRYPTO("des3_ede");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("DES & Triple DES EDE Cipher Algorithms");