[PATCH 1/3] crypto: s390 - Remove des and des3_ede code

Eric Biggers
2026-03-26T20:12:53Z

Since DES and Triple DES are obsolete, there is very little point in
maintining architecture-optimized code for them. Remove it.

Signed-off-by: Eric Biggers <ebiggers@kernel.org>
---
arch/s390/configs/debug_defconfig | 1 -
arch/s390/configs/defconfig | 1 -
arch/s390/crypto/Kconfig | 16 -
arch/s390/crypto/Makefile | 1 -
arch/s390/crypto/des_s390.c | 502 ------------------------------
5 files changed, 521 deletions(-)
delete mode 100644 arch/s390/crypto/des_s390.c

diff --git a/arch/s390/configs/debug_defconfig b/arch/s390/configs/debug_defconfig
index 98fd0a2f51c6..74e4bb236623 100644
--- a/arch/s390/configs/debug_defconfig
+++ b/arch/s390/configs/debug_defconfig
@@ -809,11 +809,10 @@ CONFIG_CRYPTO_USER_API_HASH=m
CONFIG_CRYPTO_USER_API_SKCIPHER=m
CONFIG_CRYPTO_USER_API_RNG=m
CONFIG_CRYPTO_USER_API_AEAD=m
CONFIG_CRYPTO_GHASH_S390=m
CONFIG_CRYPTO_AES_S390=m
-CONFIG_CRYPTO_DES_S390=m
CONFIG_CRYPTO_HMAC_S390=m
CONFIG_ZCRYPT=m
CONFIG_PKEY=m
CONFIG_PKEY_CCA=m
CONFIG_PKEY_EP11=m
diff --git a/arch/s390/configs/defconfig b/arch/s390/configs/defconfig
index 0f4cedcab3ce..5cb7b715ba6b 100644
--- a/arch/s390/configs/defconfig
+++ b/arch/s390/configs/defconfig
@@ -794,11 +794,10 @@ CONFIG_CRYPTO_USER_API_HASH=m
CONFIG_CRYPTO_USER_API_SKCIPHER=m
CONFIG_CRYPTO_USER_API_RNG=m
CONFIG_CRYPTO_USER_API_AEAD=m
CONFIG_CRYPTO_GHASH_S390=m
CONFIG_CRYPTO_AES_S390=m
-CONFIG_CRYPTO_DES_S390=m
CONFIG_CRYPTO_HMAC_S390=m
CONFIG_ZCRYPT=m
CONFIG_PKEY=m
CONFIG_PKEY_CCA=m
CONFIG_PKEY_EP11=m
diff --git a/arch/s390/crypto/Kconfig b/arch/s390/crypto/Kconfig
index 79a2d0034258..4218d21f1f00 100644
--- a/arch/s390/crypto/Kconfig
+++ b/arch/s390/crypto/Kconfig
@@ -29,26 +29,10 @@ config CRYPTO_AES_S390

As of z196 the CTR mode is hardware accelerated for all AES
key sizes and XTS mode is hardware accelerated for 256 and
512 bit keys.

-config CRYPTO_DES_S390
- tristate "Ciphers: DES and Triple DES EDE, modes: ECB, CBC, CTR"
- select CRYPTO_ALGAPI
- select CRYPTO_SKCIPHER
- select CRYPTO_LIB_DES
- help
- Block ciphers: DES (FIPS 46-2) cipher algorithm
- Block ciphers: Triple DES EDE (FIPS 46-3) cipher algorithm
- Length-preserving ciphers: DES with ECB, CBC, and CTR modes
- Length-preserving ciphers: Triple DES EDED with ECB, CBC, and CTR modes
-
- Architecture: s390
-
- As of z990 the ECB and CBC mode are hardware accelerated.
- As of z196 the CTR mode is hardware accelerated.
-
config CRYPTO_HMAC_S390
tristate "Keyed-hash message authentication code: HMAC"
select CRYPTO_HASH
help
s390 specific HMAC hardware support for SHA224, SHA256, SHA384 and
diff --git a/arch/s390/crypto/Makefile b/arch/s390/crypto/Makefile
index 387a229e1038..bf5e061ebf13 100644
--- a/arch/s390/crypto/Makefile
+++ b/arch/s390/crypto/Makefile
@@ -1,11 +1,10 @@
# SPDX-License-Identifier: GPL-2.0
#
# Cryptographic API
#

-obj-$(CONFIG_CRYPTO_DES_S390) += des_s390.o
obj-$(CONFIG_CRYPTO_AES_S390) += aes_s390.o
obj-$(CONFIG_CRYPTO_PAES_S390) += paes_s390.o
obj-$(CONFIG_S390_PRNG) += prng.o
obj-$(CONFIG_CRYPTO_GHASH_S390) += ghash_s390.o
obj-$(CONFIG_CRYPTO_HMAC_S390) += hmac_s390.o
diff --git a/arch/s390/crypto/des_s390.c b/arch/s390/crypto/des_s390.c
deleted file mode 100644
index 8e75b83a5ddc..000000000000
--- a/arch/s390/crypto/des_s390.c
+++ /dev/null
@@ -1,502 +0,0 @@
-// 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/internal/des.h>
-#include <crypto/internal/skcipher.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);
- int err;
-
- err = crypto_des_verify_key(tfm, key);
- if (err)
- return err;
-
- memcpy(ctx->key, key, key_len);
- return 0;
-}
-
-static int des_setkey_skcipher(struct crypto_skcipher *tfm, const u8 *key,
- unsigned int key_len)
-{
- return des_setkey(crypto_skcipher_tfm(tfm), key, key_len);
-}
-
-static void s390_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 s390_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 = s390_des_encrypt,
- .cia_decrypt = s390_des_decrypt,
- }
- }
-};
-
-static int ecb_desall_crypt(struct skcipher_request *req, unsigned long fc)
-{
- struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
- struct s390_des_ctx *ctx = crypto_skcipher_ctx(tfm);
- struct skcipher_walk walk;
- unsigned int nbytes, n;
- int ret;
-
- ret = skcipher_walk_virt(&walk, req, false);
- while ((nbytes = walk.nbytes) != 0) {
- /* 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 = skcipher_walk_done(&walk, nbytes - n);
- }
- return ret;
-}
-
-static int cbc_desall_crypt(struct skcipher_request *req, unsigned long fc)
-{
- struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
- struct s390_des_ctx *ctx = crypto_skcipher_ctx(tfm);
- struct skcipher_walk walk;
- unsigned int nbytes, n;
- int ret;
- struct {
- u8 iv[DES_BLOCK_SIZE];
- u8 key[DES3_KEY_SIZE];
- } param;
-
- ret = skcipher_walk_virt(&walk, req, false);
- if (ret)
- return ret;
- memcpy(param.iv, walk.iv, DES_BLOCK_SIZE);
- memcpy(param.key, ctx->key, DES3_KEY_SIZE);
- while ((nbytes = walk.nbytes) != 0) {
- /* only use complete blocks */
- n = nbytes & ~(DES_BLOCK_SIZE - 1);
- cpacf_kmc(fc, &param, walk.dst.virt.addr,
- walk.src.virt.addr, n);
- memcpy(walk.iv, param.iv, DES_BLOCK_SIZE);
- ret = skcipher_walk_done(&walk, nbytes - n);
- }
- return ret;
-}
-
-static int ecb_des_encrypt(struct skcipher_request *req)
-{
- return ecb_desall_crypt(req, CPACF_KM_DEA);
-}
-
-static int ecb_des_decrypt(struct skcipher_request *req)
-{
- return ecb_desall_crypt(req, CPACF_KM_DEA | CPACF_DECRYPT);
-}
-
-static struct skcipher_alg ecb_des_alg = {
- .base.cra_name = "ecb(des)",
- .base.cra_driver_name = "ecb-des-s390",
- .base.cra_priority = 400, /* combo: des + ecb */
- .base.cra_blocksize = DES_BLOCK_SIZE,
- .base.cra_ctxsize = sizeof(struct s390_des_ctx),
- .base.cra_module = THIS_MODULE,
- .min_keysize = DES_KEY_SIZE,
- .max_keysize = DES_KEY_SIZE,
- .setkey = des_setkey_skcipher,
- .encrypt = ecb_des_encrypt,
- .decrypt = ecb_des_decrypt,
-};
-
-static int cbc_des_encrypt(struct skcipher_request *req)
-{
- return cbc_desall_crypt(req, CPACF_KMC_DEA);
-}
-
-static int cbc_des_decrypt(struct skcipher_request *req)
-{
- return cbc_desall_crypt(req, CPACF_KMC_DEA | CPACF_DECRYPT);
-}
-
-static struct skcipher_alg cbc_des_alg = {
- .base.cra_name = "cbc(des)",
- .base.cra_driver_name = "cbc-des-s390",
- .base.cra_priority = 400, /* combo: des + cbc */
- .base.cra_blocksize = DES_BLOCK_SIZE,
- .base.cra_ctxsize = sizeof(struct s390_des_ctx),
- .base.cra_module = THIS_MODULE,
- .min_keysize = DES_KEY_SIZE,
- .max_keysize = DES_KEY_SIZE,
- .ivsize = DES_BLOCK_SIZE,
- .setkey = des_setkey_skcipher,
- .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 additionally 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);
- int err;
-
- err = crypto_des3_ede_verify_key(tfm, key);
- if (err)
- return err;
-
- memcpy(ctx->key, key, key_len);
- return 0;
-}
-
-static int des3_setkey_skcipher(struct crypto_skcipher *tfm, const u8 *key,
- unsigned int key_len)
-{
- return des3_setkey(crypto_skcipher_tfm(tfm), key, key_len);
-}
-
-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 skcipher_request *req)
-{
- return ecb_desall_crypt(req, CPACF_KM_TDEA_192);
-}
-
-static int ecb_des3_decrypt(struct skcipher_request *req)
-{
- return ecb_desall_crypt(req, CPACF_KM_TDEA_192 | CPACF_DECRYPT);
-}
-
-static struct skcipher_alg ecb_des3_alg = {
- .base.cra_name = "ecb(des3_ede)",
- .base.cra_driver_name = "ecb-des3_ede-s390",
- .base.cra_priority = 400, /* combo: des3 + ecb */
- .base.cra_blocksize = DES_BLOCK_SIZE,
- .base.cra_ctxsize = sizeof(struct s390_des_ctx),
- .base.cra_module = THIS_MODULE,
- .min_keysize = DES3_KEY_SIZE,
- .max_keysize = DES3_KEY_SIZE,
- .setkey = des3_setkey_skcipher,
- .encrypt = ecb_des3_encrypt,
- .decrypt = ecb_des3_decrypt,
-};
-
-static int cbc_des3_encrypt(struct skcipher_request *req)
-{
- return cbc_desall_crypt(req, CPACF_KMC_TDEA_192);
-}
-
-static int cbc_des3_decrypt(struct skcipher_request *req)
-{
- return cbc_desall_crypt(req, CPACF_KMC_TDEA_192 | CPACF_DECRYPT);
-}
-
-static struct skcipher_alg cbc_des3_alg = {
- .base.cra_name = "cbc(des3_ede)",
- .base.cra_driver_name = "cbc-des3_ede-s390",
- .base.cra_priority = 400, /* combo: des3 + cbc */
- .base.cra_blocksize = DES_BLOCK_SIZE,
- .base.cra_ctxsize = sizeof(struct s390_des_ctx),
- .base.cra_module = THIS_MODULE,
- .min_keysize = DES3_KEY_SIZE,
- .max_keysize = DES3_KEY_SIZE,
- .ivsize = DES_BLOCK_SIZE,
- .setkey = des3_setkey_skcipher,
- .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 skcipher_request *req, unsigned long fc)
-{
- struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
- struct s390_des_ctx *ctx = crypto_skcipher_ctx(tfm);
- u8 buf[DES_BLOCK_SIZE], *ctrptr;
- struct skcipher_walk walk;
- unsigned int n, nbytes;
- int ret, locked;
-
- locked = mutex_trylock(&ctrblk_lock);
-
- ret = skcipher_walk_virt(&walk, req, false);
- 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 = skcipher_walk_done(&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 = skcipher_walk_done(&walk, 0);
- }
- return ret;
-}
-
-static int ctr_des_crypt(struct skcipher_request *req)
-{
- return ctr_desall_crypt(req, CPACF_KMCTR_DEA);
-}
-
-static struct skcipher_alg ctr_des_alg = {
- .base.cra_name = "ctr(des)",
- .base.cra_driver_name = "ctr-des-s390",
- .base.cra_priority = 400, /* combo: des + ctr */
- .base.cra_blocksize = 1,
- .base.cra_ctxsize = sizeof(struct s390_des_ctx),
- .base.cra_module = THIS_MODULE,
- .min_keysize = DES_KEY_SIZE,
- .max_keysize = DES_KEY_SIZE,
- .ivsize = DES_BLOCK_SIZE,
- .setkey = des_setkey_skcipher,
- .encrypt = ctr_des_crypt,
- .decrypt = ctr_des_crypt,
- .chunksize = DES_BLOCK_SIZE,
-};
-
-static int ctr_des3_crypt(struct skcipher_request *req)
-{
- return ctr_desall_crypt(req, CPACF_KMCTR_TDEA_192);
-}
-
-static struct skcipher_alg ctr_des3_alg = {
- .base.cra_name = "ctr(des3_ede)",
- .base.cra_driver_name = "ctr-des3_ede-s390",
- .base.cra_priority = 400, /* combo: des3 + ede */
- .base.cra_blocksize = 1,
- .base.cra_ctxsize = sizeof(struct s390_des_ctx),
- .base.cra_module = THIS_MODULE,
- .min_keysize = DES3_KEY_SIZE,
- .max_keysize = DES3_KEY_SIZE,
- .ivsize = DES_BLOCK_SIZE,
- .setkey = des3_setkey_skcipher,
- .encrypt = ctr_des3_crypt,
- .decrypt = ctr_des3_crypt,
- .chunksize = DES_BLOCK_SIZE,
-};
-
-static struct crypto_alg *des_s390_algs_ptr[2];
-static int des_s390_algs_num;
-static struct skcipher_alg *des_s390_skciphers_ptr[6];
-static int des_s390_skciphers_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 int des_s390_register_skcipher(struct skcipher_alg *alg)
-{
- int ret;
-
- ret = crypto_register_skcipher(alg);
- if (!ret)
- des_s390_skciphers_ptr[des_s390_skciphers_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]);
- while (des_s390_skciphers_num--)
- crypto_unregister_skcipher(des_s390_skciphers_ptr[des_s390_skciphers_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_skcipher(&ecb_des_alg);
- if (ret)
- goto out_err;
- }
- if (cpacf_test_func(&kmc_functions, CPACF_KMC_DEA)) {
- ret = des_s390_register_skcipher(&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_skcipher(&ecb_des3_alg);
- if (ret)
- goto out_err;
- }
- if (cpacf_test_func(&kmc_functions, CPACF_KMC_TDEA_192)) {
- ret = des_s390_register_skcipher(&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_skcipher(&ctr_des_alg);
- if (ret)
- goto out_err;
- }
- if (cpacf_test_func(&kmctr_functions, CPACF_KMCTR_TDEA_192)) {
- ret = des_s390_register_skcipher(&ctr_des3_alg);
- if (ret)
- goto out_err;
- }
-
- return 0;
-out_err:
- des_s390_exit();
- return ret;
-}
-
-module_cpu_feature_match(S390_CPU_FEATURE_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");
--
2.53.0