[PATCH] s390: sha256 support

Add support for the hardware accelerated sha256 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>

6 files changed, 171 insertions, 1 deletions

diff --git a/arch/s390/crypto/Makefile b/arch/s390/crypto/Makefile
index 50843f8d0951..3fccf61ee1d1 100644
--- a/arch/s390/crypto/Makefile
+++ b/arch/s390/crypto/Makefile
@@ -3,6 +3,7 @@
 #
 
 obj-$(CONFIG_CRYPTO_SHA1_S390) += sha1_s390.o
+obj-$(CONFIG_CRYPTO_SHA256_S390) += sha256_s390.o
 obj-$(CONFIG_CRYPTO_DES_S390) += des_s390.o des_check_key.o
 
 obj-$(CONFIG_CRYPTO_TEST) += crypt_s390_query.o
diff --git a/arch/s390/crypto/crypt_s390.h b/arch/s390/crypto/crypt_s390.h
index 4d24f6689755..b70a410ac311 100644
--- a/arch/s390/crypto/crypt_s390.h
+++ b/arch/s390/crypto/crypt_s390.h
@@ -61,6 +61,7 @@ enum crypt_s390_kmc_func {
 enum crypt_s390_kimd_func {
         KIMD_QUERY   = CRYPT_S390_KIMD | 0,
         KIMD_SHA_1   = CRYPT_S390_KIMD | 1,
+        KIMD_SHA_256 = CRYPT_S390_KIMD | 2,
 };
 
 /* function codes for KLMD (COMPUTE LAST MESSAGE DIGEST)
@@ -69,6 +70,7 @@ enum crypt_s390_kimd_func {
 enum crypt_s390_klmd_func {
         KLMD_QUERY   = CRYPT_S390_KLMD | 0,
         KLMD_SHA_1   = CRYPT_S390_KLMD | 1,
+        KLMD_SHA_256 = CRYPT_S390_KLMD | 2,
 };
 
 /* function codes for KMAC (COMPUTE MESSAGE AUTHENTICATION CODE)
diff --git a/arch/s390/crypto/crypt_s390_query.c b/arch/s390/crypto/crypt_s390_query.c
index 0fa6bdf197cf..67081b81a4a3 100644
--- a/arch/s390/crypto/crypt_s390_query.c
+++ b/arch/s390/crypto/crypt_s390_query.c
@@ -48,16 +48,20 @@ static void query_available_functions(void)
                 crypt_s390_func_available(KIMD_QUERY));
         printk(KERN_INFO "KIMD_SHA_1: %d\n",
                 crypt_s390_func_available(KIMD_SHA_1));
+        printk(KERN_INFO "KIMD_SHA_256: %d\n",
+                crypt_s390_func_available(KIMD_SHA_256));
 
         /* query available KLMD functions */
         printk(KERN_INFO "KLMD_QUERY: %d\n",
                 crypt_s390_func_available(KLMD_QUERY));
         printk(KERN_INFO "KLMD_SHA_1: %d\n",
                 crypt_s390_func_available(KLMD_SHA_1));
+        printk(KERN_INFO "KLMD_SHA_256: %d\n",
+                crypt_s390_func_available(KLMD_SHA_256));
 
         /* query available KMAC functions */
         printk(KERN_INFO "KMAC_QUERY: %d\n",
-                crypt_s3990_func_available(KMAC_QUERY));
+                crypt_s390_func_available(KMAC_QUERY));
         printk(KERN_INFO "KMAC_DEA: %d\n",
                 crypt_s390_func_available(KMAC_DEA));
         printk(KERN_INFO "KMAC_TDEA_128: %d\n",
diff --git a/arch/s390/crypto/sha256_s390.c b/arch/s390/crypto/sha256_s390.c
new file mode 100644
index 000000000000..b75bdbd476c7
--- /dev/null
+++ b/arch/s390/crypto/sha256_s390.c
@@ -0,0 +1,151 @@
+/*
+ * Cryptographic API.
+ *
+ * s390 implementation of the SHA256 Secure Hash Algorithm.
+ *
+ * s390 Version:
+ *   Copyright (C) 2005 IBM Deutschland GmbH, IBM Corporation
+ *   Author(s): Jan Glauber (jang@de.ibm.com)
+ *
+ * Derived from "crypto/sha256.c"
+ * and "arch/s390/crypto/sha1_s390.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/init.h>
+#include <linux/module.h>
+#include <linux/crypto.h>
+
+#include "crypt_s390.h"
+
+#define SHA256_DIGEST_SIZE      32
+#define SHA256_BLOCK_SIZE       64
+
+struct s390_sha256_ctx {
+        u64 count;
+        u32 state[8];
+        u8 buf[2 * SHA256_BLOCK_SIZE];
+};
+
+static void sha256_init(void *ctx)
+{
+        struct s390_sha256_ctx *sctx = ctx;
+
+        sctx->state[0] = 0x6a09e667;
+        sctx->state[1] = 0xbb67ae85;
+        sctx->state[2] = 0x3c6ef372;
+        sctx->state[3] = 0xa54ff53a;
+        sctx->state[4] = 0x510e527f;
+        sctx->state[5] = 0x9b05688c;
+        sctx->state[6] = 0x1f83d9ab;
+        sctx->state[7] = 0x5be0cd19;
+        sctx->count = 0;
+        memset(sctx->buf, 0, sizeof(sctx->buf));
+}
+
+static void sha256_update(void *ctx, const u8 *data, unsigned int len)
+{
+        struct s390_sha256_ctx *sctx = ctx;
+        unsigned int index;
+
+        /* how much is already in the buffer? */
+        index = sctx->count / 8 & 0x3f;
+
+        /* update message bit length */
+        sctx->count += len * 8;
+
+        /* process one block */
+        if ((index + len) >= SHA256_BLOCK_SIZE) {
+                memcpy(sctx->buf + index, data, SHA256_BLOCK_SIZE - index);
+                crypt_s390_kimd(KIMD_SHA_256, sctx->state, sctx->buf,
+                                SHA256_BLOCK_SIZE);
+                data += SHA256_BLOCK_SIZE - index;
+                len -= SHA256_BLOCK_SIZE - index;
+        }
+
+        /* anything left? */
+        if (len)
+                memcpy(sctx->buf + index , data, len);
+}
+
+static void pad_message(struct s390_sha256_ctx* sctx)
+{
+        int index, end;
+
+        index = sctx->count / 8 & 0x3f;
+        end = index < 56 ? SHA256_BLOCK_SIZE : 2 * SHA256_BLOCK_SIZE;
+
+        /* start pad with 1 */
+        sctx->buf[index] = 0x80;
+
+        /* pad with zeros */
+        index++;
+        memset(sctx->buf + index, 0x00, end - index - 8);
+
+        /* append message length */
+        memcpy(sctx->buf + end - 8, &sctx->count, sizeof sctx->count);
+
+        sctx->count = end * 8;
+}
+
+/* Add padding and return the message digest */
+static void sha256_final(void* ctx, u8 *out)
+{
+        struct s390_sha256_ctx *sctx = ctx;
+
+        /* must perform manual padding */
+        pad_message(sctx);
+
+        crypt_s390_kimd(KIMD_SHA_256, sctx->state, sctx->buf,
+                        sctx->count / 8);
+
+        /* copy digest to out */
+        memcpy(out, sctx->state, SHA256_DIGEST_SIZE);
+
+        /* wipe context */
+        memset(sctx, 0, sizeof *sctx);
+}
+
+static struct crypto_alg alg = {
+        .cra_name       =       "sha256",
+        .cra_flags      =       CRYPTO_ALG_TYPE_DIGEST,
+        .cra_blocksize  =       SHA256_BLOCK_SIZE,
+        .cra_ctxsize    =       sizeof(struct s390_sha256_ctx),
+        .cra_module     =       THIS_MODULE,
+        .cra_list       =       LIST_HEAD_INIT(alg.cra_list),
+        .cra_u          =       { .digest = {
+        .dia_digestsize =       SHA256_DIGEST_SIZE,
+        .dia_init       =       sha256_init,
+        .dia_update     =       sha256_update,
+        .dia_final      =       sha256_final } }
+};
+
+static int init(void)
+{
+        int ret;
+
+        if (!crypt_s390_func_available(KIMD_SHA_256))
+                return -ENOSYS;
+
+        ret = crypto_register_alg(&alg);
+        if (ret != 0)
+                printk(KERN_INFO "crypt_s390: sha256_s390 couldn't be loaded.");
+        return ret;
+}
+
+static void __exit fini(void)
+{
+        crypto_unregister_alg(&alg);
+}
+
+module_init(init);
+module_exit(fini);
+
+MODULE_ALIAS("sha256");
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("SHA256 Secure Hash Algorithm");
diff --git a/arch/s390/defconfig b/arch/s390/defconfig
index 0cb2995bf21c..fd00a9f53d53 100644
--- a/arch/s390/defconfig
+++ b/arch/s390/defconfig
@@ -634,6 +634,7 @@ CONFIG_CRYPTO=y
 # CONFIG_CRYPTO_SHA1 is not set
 # CONFIG_CRYPTO_SHA1_S390 is not set
 # CONFIG_CRYPTO_SHA256 is not set
+# CONFIG_CRYPTO_SHA256_S390 is not set
 # CONFIG_CRYPTO_SHA512 is not set
 # CONFIG_CRYPTO_WP512 is not set
 # CONFIG_CRYPTO_TGR192 is not set
diff --git a/crypto/Kconfig b/crypto/Kconfig
index 85af57100923..9fdab742b10f 100644
--- a/crypto/Kconfig
+++ b/crypto/Kconfig
@@ -44,6 +44,7 @@ config CRYPTO_SHA1_S390
         tristate "SHA1 digest algorithm (s390)"
         depends on CRYPTO && ARCH_S390
         help
+          This is the s390 hardware accelerated implementation of the
           SHA-1 secure hash standard (FIPS 180-1/DFIPS 180-2).
 
 config CRYPTO_SHA256
@@ -55,6 +56,16 @@ config CRYPTO_SHA256
           This version of SHA implements a 256 bit hash with 128 bits of
           security against collision attacks.
 
+config CRYPTO_SHA256_S390
+        tristate "SHA256 digest algorithm (s390)"
+        depends on CRYPTO && ARCH_S390
+        help
+          This is the s390 hardware accelerated implementation of the
+          SHA256 secure hash standard (DFIPS 180-2).
+
+          This version of SHA implements a 256 bit hash with 128 bits of
+          security against collision attacks.
+
 config CRYPTO_SHA512
         tristate "SHA384 and SHA512 digest algorithms"
         depends on CRYPTO