diff options
Diffstat (limited to 'arch/s390/crypto/sha256_s390.c')
-rw-r--r-- | arch/s390/crypto/sha256_s390.c | 151 |
1 files changed, 151 insertions, 0 deletions
diff --git a/arch/s390/crypto/sha256_s390.c b/arch/s390/crypto/sha256_s390.c new file mode 100644 index 0000000..b75bdbd --- /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"); |