arch/s390/crypto/des_s390.c - third_party/linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0+
 /*
  * 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)
  */

 #include <linux/init.h>
 #include <linux/module.h>
 #include <linux/cpufeature.h>
 #include <linux/crypto.h>
 #include <linux/fips.h>
 #include <linux/mutex.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_MUTEX(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, unsigned long fc,
 			    struct blkcipher_walk *walk)
 {
 	struct s390_des_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
 	unsigned int nbytes, n;
 	int ret;

 	ret = blkcipher_walk_virt(desc, walk);
 	while ((nbytes = walk->nbytes) >= DES_BLOCK_SIZE) {
 		/* only use complete blocks */
 		n = nbytes & ~(DES_BLOCK_SIZE - 1);
 		cpacf_km(fc, ctx->key, walk->dst.virt.addr,
 			 walk->src.virt.addr, n);
 		ret = blkcipher_walk_done(desc, walk, nbytes - n);
 	}
 	return ret;
 }

 static int cbc_desall_crypt(struct blkcipher_desc *desc, unsigned long fc,
 			    struct blkcipher_walk *walk)
 {
 	struct s390_des_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
 	unsigned int nbytes, n;
 	int ret;
 	struct {
 		u8 iv[DES_BLOCK_SIZE];
 		u8 key[DES3_KEY_SIZE];
 	} param;

 	ret = blkcipher_walk_virt(desc, walk);
 	memcpy(param.iv, walk->iv, DES_BLOCK_SIZE);
 	memcpy(param.key, ctx->key, DES3_KEY_SIZE);
 	while ((nbytes = walk->nbytes) >= DES_BLOCK_SIZE) {
 		/* only use complete blocks */
 		n = nbytes & ~(DES_BLOCK_SIZE - 1);
 		cpacf_kmc(fc, &param, walk->dst.virt.addr,
 			  walk->src.virt.addr, n);
 		ret = blkcipher_walk_done(desc, walk, nbytes - n);
 	}
 	memcpy(walk->iv, param.iv, DES_BLOCK_SIZE);
 	return ret;
 }

 static int ecb_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 ecb_desall_crypt(desc, CPACF_KM_DEA, &walk);
 }

 static int ecb_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 ecb_desall_crypt(desc, CPACF_KM_DEA | CPACF_DECRYPT, &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.
  *
  *   In fips mode additinally check for all 3 keys are unique.
  *
  */
 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;
 	}

 	/* in fips mode, ensure k1 != k2 and k2 != k3 and k1 != k3 */
 	if (fips_enabled &&
 	    !(crypto_memneq(key, &key[DES_KEY_SIZE], DES_KEY_SIZE) &&
 	      crypto_memneq(&key[DES_KEY_SIZE], &key[DES_KEY_SIZE * 2],
 			    DES_KEY_SIZE) &&
 	      crypto_memneq(key, &key[DES_KEY_SIZE * 2], DES_KEY_SIZE))) {
 		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 blkcipher_walk walk;

 	blkcipher_walk_init(&walk, dst, src, nbytes);
 	return ecb_desall_crypt(desc, CPACF_KM_TDEA_192, &walk);
 }

 static int ecb_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 ecb_desall_crypt(desc, CPACF_KM_TDEA_192 | CPACF_DECRYPT,
 				&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, u8 *iv, 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);
 	memcpy(ctrptr, iv, DES_BLOCK_SIZE);
 	for (i = (n / DES_BLOCK_SIZE) - 1; i > 0; i--) {
 		memcpy(ctrptr + DES_BLOCK_SIZE, ctrptr, DES_BLOCK_SIZE);
 		crypto_inc(ctrptr + DES_BLOCK_SIZE, DES_BLOCK_SIZE);
 		ctrptr += DES_BLOCK_SIZE;
 	}
 	return n;
 }

 static int ctr_desall_crypt(struct blkcipher_desc *desc, unsigned long fc,
 			    struct blkcipher_walk *walk)
 {
 	struct s390_des_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
 	u8 buf[DES_BLOCK_SIZE], *ctrptr;
 	unsigned int n, nbytes;
 	int ret, locked;

 	locked = mutex_trylock(&ctrblk_lock);

 	ret = blkcipher_walk_virt_block(desc, walk, DES_BLOCK_SIZE);
 	while ((nbytes = walk->nbytes) >= DES_BLOCK_SIZE) {
 		n = DES_BLOCK_SIZE;
 		if (nbytes >= 2*DES_BLOCK_SIZE && locked)
 			n = __ctrblk_init(ctrblk, walk->iv, nbytes);
 		ctrptr = (n > DES_BLOCK_SIZE) ? ctrblk : walk->iv;
 		cpacf_kmctr(fc, ctx->key, walk->dst.virt.addr,
 			    walk->src.virt.addr, n, ctrptr);
 		if (ctrptr == ctrblk)
 			memcpy(walk->iv, ctrptr + n - DES_BLOCK_SIZE,
 				DES_BLOCK_SIZE);
 		crypto_inc(walk->iv, DES_BLOCK_SIZE);
 		ret = blkcipher_walk_done(desc, walk, nbytes - n);
 	}
 	if (locked)
 		mutex_unlock(&ctrblk_lock);
 	/* final block may be < DES_BLOCK_SIZE, copy only nbytes */
 	if (nbytes) {
 		cpacf_kmctr(fc, ctx->key, buf, walk->src.virt.addr,
 			    DES_BLOCK_SIZE, walk->iv);
 		memcpy(walk->dst.virt.addr, buf, nbytes);
 		crypto_inc(walk->iv, DES_BLOCK_SIZE);
 		ret = blkcipher_walk_done(desc, walk, 0);
 	}
 	return ret;
 }

 static int ctr_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 ctr_desall_crypt(desc, CPACF_KMCTR_DEA, &walk);
 }

 static int ctr_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 ctr_desall_crypt(desc, CPACF_KMCTR_DEA | CPACF_DECRYPT, &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 blkcipher_walk walk;

 	blkcipher_walk_init(&walk, dst, src, nbytes);
 	return ctr_desall_crypt(desc, CPACF_KMCTR_TDEA_192, &walk);
 }

 static int ctr_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 ctr_desall_crypt(desc, CPACF_KMCTR_TDEA_192 | CPACF_DECRYPT,
 				&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");
	// SPDX-License-Identifier: GPL-2.0+
	/*
	* 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)
	*/

	#include <linux/init.h>
	#include <linux/module.h>
	#include <linux/cpufeature.h>
	#include <linux/crypto.h>
	#include <linux/fips.h>
	#include <linux/mutex.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_MUTEX(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, unsigned long fc,
	struct blkcipher_walk *walk)
	{
	struct s390_des_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
	unsigned int nbytes, n;
	int ret;

	ret = blkcipher_walk_virt(desc, walk);
	while ((nbytes = walk->nbytes) >= DES_BLOCK_SIZE) {
	/* only use complete blocks */
	n = nbytes & ~(DES_BLOCK_SIZE - 1);
	cpacf_km(fc, ctx->key, walk->dst.virt.addr,
	walk->src.virt.addr, n);
	ret = blkcipher_walk_done(desc, walk, nbytes - n);
	}
	return ret;
	}

	static int cbc_desall_crypt(struct blkcipher_desc *desc, unsigned long fc,
	struct blkcipher_walk *walk)
	{
	struct s390_des_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
	unsigned int nbytes, n;
	int ret;
	struct {
	u8 iv[DES_BLOCK_SIZE];
	u8 key[DES3_KEY_SIZE];
	} param;

	ret = blkcipher_walk_virt(desc, walk);
	memcpy(param.iv, walk->iv, DES_BLOCK_SIZE);
	memcpy(param.key, ctx->key, DES3_KEY_SIZE);
	while ((nbytes = walk->nbytes) >= DES_BLOCK_SIZE) {
	/* only use complete blocks */
	n = nbytes & ~(DES_BLOCK_SIZE - 1);
	cpacf_kmc(fc, &param, walk->dst.virt.addr,
	walk->src.virt.addr, n);
	ret = blkcipher_walk_done(desc, walk, nbytes - n);
	}
	memcpy(walk->iv, param.iv, DES_BLOCK_SIZE);
	return ret;
	}

	static int ecb_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 ecb_desall_crypt(desc, CPACF_KM_DEA, &walk);
	}

	static int ecb_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 ecb_desall_crypt(desc, CPACF_KM_DEA \| CPACF_DECRYPT, &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.
	*
	* In fips mode additinally check for all 3 keys are unique.
	*
	*/
	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;
	}

	/* in fips mode, ensure k1 != k2 and k2 != k3 and k1 != k3 */
	if (fips_enabled &&
	!(crypto_memneq(key, &key[DES_KEY_SIZE], DES_KEY_SIZE) &&
	crypto_memneq(&key[DES_KEY_SIZE], &key[DES_KEY_SIZE * 2],
	DES_KEY_SIZE) &&
	crypto_memneq(key, &key[DES_KEY_SIZE * 2], DES_KEY_SIZE))) {
	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 blkcipher_walk walk;

	blkcipher_walk_init(&walk, dst, src, nbytes);
	return ecb_desall_crypt(desc, CPACF_KM_TDEA_192, &walk);
	}

	static int ecb_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 ecb_desall_crypt(desc, CPACF_KM_TDEA_192 \| CPACF_DECRYPT,
	&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, u8 iv, 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);
	memcpy(ctrptr, iv, DES_BLOCK_SIZE);
	for (i = (n / DES_BLOCK_SIZE) - 1; i > 0; i--) {
	memcpy(ctrptr + DES_BLOCK_SIZE, ctrptr, DES_BLOCK_SIZE);
	crypto_inc(ctrptr + DES_BLOCK_SIZE, DES_BLOCK_SIZE);
	ctrptr += DES_BLOCK_SIZE;
	}
	return n;
	}

	static int ctr_desall_crypt(struct blkcipher_desc *desc, unsigned long fc,
	struct blkcipher_walk *walk)
	{
	struct s390_des_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
	u8 buf[DES_BLOCK_SIZE], *ctrptr;
	unsigned int n, nbytes;
	int ret, locked;

	locked = mutex_trylock(&ctrblk_lock);

	ret = blkcipher_walk_virt_block(desc, walk, DES_BLOCK_SIZE);
	while ((nbytes = walk->nbytes) >= DES_BLOCK_SIZE) {
	n = DES_BLOCK_SIZE;
	if (nbytes >= 2*DES_BLOCK_SIZE && locked)
	n = __ctrblk_init(ctrblk, walk->iv, nbytes);
	ctrptr = (n > DES_BLOCK_SIZE) ? ctrblk : walk->iv;
	cpacf_kmctr(fc, ctx->key, walk->dst.virt.addr,
	walk->src.virt.addr, n, ctrptr);
	if (ctrptr == ctrblk)
	memcpy(walk->iv, ctrptr + n - DES_BLOCK_SIZE,
	DES_BLOCK_SIZE);
	crypto_inc(walk->iv, DES_BLOCK_SIZE);
	ret = blkcipher_walk_done(desc, walk, nbytes - n);
	}
	if (locked)
	mutex_unlock(&ctrblk_lock);
	/* final block may be < DES_BLOCK_SIZE, copy only nbytes */
	if (nbytes) {
	cpacf_kmctr(fc, ctx->key, buf, walk->src.virt.addr,
	DES_BLOCK_SIZE, walk->iv);
	memcpy(walk->dst.virt.addr, buf, nbytes);
	crypto_inc(walk->iv, DES_BLOCK_SIZE);
	ret = blkcipher_walk_done(desc, walk, 0);
	}
	return ret;
	}

	static int ctr_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 ctr_desall_crypt(desc, CPACF_KMCTR_DEA, &walk);
	}

	static int ctr_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 ctr_desall_crypt(desc, CPACF_KMCTR_DEA \| CPACF_DECRYPT, &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 blkcipher_walk walk;

	blkcipher_walk_init(&walk, dst, src, nbytes);
	return ctr_desall_crypt(desc, CPACF_KMCTR_TDEA_192, &walk);
	}

	static int ctr_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 ctr_desall_crypt(desc, CPACF_KMCTR_TDEA_192 \| CPACF_DECRYPT,
	&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");