[PATCH] s390: aes support

Add support for the hardware accelerated AES crypto algorithm.

Signed-off-by: Jan Glauber <jan.glauber@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 248 insertions, 0 deletions

diff --git a/arch/s390/crypto/aes_s390.c b/arch/s390/crypto/aes_s390.c
new file mode 100644
index 000000000000..7a1033d8e00f
--- /dev/null
+++ b/arch/s390/crypto/aes_s390.c
@@ -0,0 +1,248 @@
+/*
+ * Cryptographic API.
+ *
+ * s390 implementation of the AES Cipher Algorithm.
+ *
+ * s390 Version:
+ *   Copyright (C) 2005 IBM Deutschland GmbH, IBM Corporation
+ *   Author(s): Jan Glauber (jang@de.ibm.com)
+ *
+ * Derived from "crypto/aes.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.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/crypto.h>
+#include "crypt_s390.h"
+
+#define AES_MIN_KEY_SIZE	16
+#define AES_MAX_KEY_SIZE	32
+
+/* data block size for all key lengths */
+#define AES_BLOCK_SIZE		16
+
+int has_aes_128 = 0;
+int has_aes_192 = 0;
+int has_aes_256 = 0;
+
+struct s390_aes_ctx {
+	u8 iv[AES_BLOCK_SIZE];
+	u8 key[AES_MAX_KEY_SIZE];
+	int key_len;
+};
+
+static int aes_set_key(void *ctx, const u8 *in_key, unsigned int key_len,
+		       u32 *flags)
+{
+	struct s390_aes_ctx *sctx = ctx;
+
+	switch (key_len) {
+	case 16:
+		if (!has_aes_128)
+			goto fail;
+		break;
+	case 24:
+		if (!has_aes_192)
+			goto fail;
+
+		break;
+	case 32:
+		if (!has_aes_256)
+			goto fail;
+		break;
+	default:
+		/* invalid key length */
+		goto fail;
+		break;
+	}
+
+	sctx->key_len = key_len;
+	memcpy(sctx->key, in_key, key_len);
+	return 0;
+fail:
+	*flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
+	return -EINVAL;
+}
+
+static void aes_encrypt(void *ctx, u8 *out, const u8 *in)
+{
+	const struct s390_aes_ctx *sctx = ctx;
+
+	switch (sctx->key_len) {
+	case 16:
+		crypt_s390_km(KM_AES_128_ENCRYPT, &sctx->key, out, in,
+			      AES_BLOCK_SIZE);
+		break;
+	case 24:
+		crypt_s390_km(KM_AES_192_ENCRYPT, &sctx->key, out, in,
+			      AES_BLOCK_SIZE);
+		break;
+	case 32:
+		crypt_s390_km(KM_AES_256_ENCRYPT, &sctx->key, out, in,
+			      AES_BLOCK_SIZE);
+		break;
+	}
+}
+
+static void aes_decrypt(void *ctx, u8 *out, const u8 *in)
+{
+	const struct s390_aes_ctx *sctx = ctx;
+
+	switch (sctx->key_len) {
+	case 16:
+		crypt_s390_km(KM_AES_128_DECRYPT, &sctx->key, out, in,
+			      AES_BLOCK_SIZE);
+		break;
+	case 24:
+		crypt_s390_km(KM_AES_192_DECRYPT, &sctx->key, out, in,
+			      AES_BLOCK_SIZE);
+		break;
+	case 32:
+		crypt_s390_km(KM_AES_256_DECRYPT, &sctx->key, out, in,
+			      AES_BLOCK_SIZE);
+		break;
+	}
+}
+
+static unsigned int aes_encrypt_ecb(const struct cipher_desc *desc, u8 *out,
+				    const u8 *in, unsigned int nbytes)
+{
+	struct s390_aes_ctx *sctx = crypto_tfm_ctx(desc->tfm);
+
+	switch (sctx->key_len) {
+	case 16:
+		crypt_s390_km(KM_AES_128_ENCRYPT, &sctx->key, out, in, nbytes);
+		break;
+	case 24:
+		crypt_s390_km(KM_AES_192_ENCRYPT, &sctx->key, out, in, nbytes);
+		break;
+	case 32:
+		crypt_s390_km(KM_AES_256_ENCRYPT, &sctx->key, out, in, nbytes);
+		break;
+	}
+	return nbytes & ~(AES_BLOCK_SIZE - 1);
+}
+
+static unsigned int aes_decrypt_ecb(const struct cipher_desc *desc, u8 *out,
+				    const u8 *in, unsigned int nbytes)
+{
+	struct s390_aes_ctx *sctx = crypto_tfm_ctx(desc->tfm);
+
+	switch (sctx->key_len) {
+	case 16:
+		crypt_s390_km(KM_AES_128_DECRYPT, &sctx->key, out, in, nbytes);
+		break;
+	case 24:
+		crypt_s390_km(KM_AES_192_DECRYPT, &sctx->key, out, in, nbytes);
+		break;
+	case 32:
+		crypt_s390_km(KM_AES_256_DECRYPT, &sctx->key, out, in, nbytes);
+		break;
+	}
+	return nbytes & ~(AES_BLOCK_SIZE - 1);
+}
+
+static unsigned int aes_encrypt_cbc(const struct cipher_desc *desc, u8 *out,
+				    const u8 *in, unsigned int nbytes)
+{
+	struct s390_aes_ctx *sctx = crypto_tfm_ctx(desc->tfm);
+
+	memcpy(&sctx->iv, desc->info, AES_BLOCK_SIZE);
+	switch (sctx->key_len) {
+	case 16:
+		crypt_s390_kmc(KMC_AES_128_ENCRYPT, &sctx->iv, out, in, nbytes);
+		break;
+	case 24:
+		crypt_s390_kmc(KMC_AES_192_ENCRYPT, &sctx->iv, out, in, nbytes);
+		break;
+	case 32:
+		crypt_s390_kmc(KMC_AES_256_ENCRYPT, &sctx->iv, out, in, nbytes);
+		break;
+	}
+	memcpy(desc->info, &sctx->iv, AES_BLOCK_SIZE);
+
+	return nbytes & ~(AES_BLOCK_SIZE - 1);
+}
+
+static unsigned int aes_decrypt_cbc(const struct cipher_desc *desc, u8 *out,
+				    const u8 *in, unsigned int nbytes)
+{
+	struct s390_aes_ctx *sctx = crypto_tfm_ctx(desc->tfm);
+
+	memcpy(&sctx->iv, desc->info, AES_BLOCK_SIZE);
+	switch (sctx->key_len) {
+	case 16:
+		crypt_s390_kmc(KMC_AES_128_DECRYPT, &sctx->iv, out, in, nbytes);
+		break;
+	case 24:
+		crypt_s390_kmc(KMC_AES_192_DECRYPT, &sctx->iv, out, in, nbytes);
+		break;
+	case 32:
+		crypt_s390_kmc(KMC_AES_256_DECRYPT, &sctx->iv, out, in, nbytes);
+		break;
+	}
+	return nbytes & ~(AES_BLOCK_SIZE - 1);
+}
+
+
+static struct crypto_alg aes_alg = {
+	.cra_name		=	"aes",
+	.cra_flags		=	CRYPTO_ALG_TYPE_CIPHER,
+	.cra_blocksize		=	AES_BLOCK_SIZE,
+	.cra_ctxsize		=	sizeof(struct s390_aes_ctx),
+	.cra_module		=	THIS_MODULE,
+	.cra_list		=	LIST_HEAD_INIT(aes_alg.cra_list),
+	.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,
+			.cia_encrypt_ecb	=	aes_encrypt_ecb,
+			.cia_decrypt_ecb	=	aes_decrypt_ecb,
+			.cia_encrypt_cbc	=	aes_encrypt_cbc,
+			.cia_decrypt_cbc	=	aes_decrypt_cbc,
+		}
+	}
+};
+
+static int __init aes_init(void)
+{
+	int ret;
+
+	if (crypt_s390_func_available(KM_AES_128_ENCRYPT))
+		has_aes_128 = 1;
+	if (crypt_s390_func_available(KM_AES_192_ENCRYPT))
+		has_aes_192 = 1;
+	if (crypt_s390_func_available(KM_AES_256_ENCRYPT))
+		has_aes_256 = 1;
+
+	if (!has_aes_128 && !has_aes_192 && !has_aes_256)
+		return -ENOSYS;
+
+	ret = crypto_register_alg(&aes_alg);
+	if (ret != 0)
+		printk(KERN_INFO "crypt_s390: aes_s390 couldn't be loaded.\n");
+	return ret;
+}
+
+static void __exit aes_fini(void)
+{
+	crypto_unregister_alg(&aes_alg);
+}
+
+module_init(aes_init);
+module_exit(aes_fini);
+
+MODULE_ALIAS("aes");
+
+MODULE_DESCRIPTION("Rijndael (AES) Cipher Algorithm");
+MODULE_LICENSE("GPL");
+