/* * Cryptographic API. * * SHA1 Secure Hash Algorithm. * * Derived from cryptoapi implementation, adapted for in-place * scatterlist interface. * * Copyright (c) Alan Smithee. * Copyright (c) Andrew McDonald <andrew@mcdonald.org.uk> * Copyright (c) Jean-Francois Dive <jef@linuxbe.org> * * 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/mm.h> #include <linux/crypto.h> #include <linux/cryptohash.h> #include <linux/types.h> #include <crypto/sha.h> #include <asm/scatterlist.h> #include <asm/byteorder.h> struct sha1_ctx { u64 count; u32 state[5]; u8 buffer[64]; }; static void sha1_init(struct crypto_tfm *tfm) { struct sha1_ctx *sctx = crypto_tfm_ctx(tfm); static const struct sha1_ctx initstate = { 0, { SHA1_H0, SHA1_H1, SHA1_H2, SHA1_H3, SHA1_H4 }, { 0, } }; *sctx = initstate; } static void sha1_update(struct crypto_tfm *tfm, const u8 *data, unsigned int len) { struct sha1_ctx *sctx = crypto_tfm_ctx(tfm); unsigned int partial, done; const u8 *src; partial = sctx->count & 0x3f; sctx->count += len; done = 0; src = data; if ((partial + len) > 63) { u32 temp[SHA_WORKSPACE_WORDS]; if (partial) { done = -partial; memcpy(sctx->buffer + partial, data, done + 64); src = sctx->buffer; } do { sha_transform(sctx->state, src, temp); done += 64; src = data + done; } while (done + 63 < len); memset(temp, 0, sizeof(temp)); partial = 0; } memcpy(sctx->buffer + partial, src, len - done); } /* Add padding and return the message digest. */ static void sha1_final(struct crypto_tfm *tfm, u8 *out) { struct sha1_ctx *sctx = crypto_tfm_ctx(tfm); __be32 *dst = (__be32 *)out; u32 i, index, padlen; __be64 bits; static const u8 padding[64] = { 0x80, }; bits = cpu_to_be64(sctx->count << 3); /* Pad out to 56 mod 64 */ index = sctx->count & 0x3f; padlen = (index < 56) ? (56 - index) : ((64+56) - index); sha1_update(tfm, padding, padlen); /* Append length */ sha1_update(tfm, (const u8 *)&bits, sizeof(bits)); /* Store state in digest */ for (i = 0; i < 5; i++) dst[i] = cpu_to_be32(sctx->state[i]); /* Wipe context */ memset(sctx, 0, sizeof *sctx); } static struct crypto_alg alg = { .cra_name = "sha1", .cra_driver_name= "sha1-generic", .cra_flags = CRYPTO_ALG_TYPE_DIGEST, .cra_blocksize = SHA1_BLOCK_SIZE, .cra_ctxsize = sizeof(struct sha1_ctx), .cra_module = THIS_MODULE, .cra_alignmask = 3, .cra_list = LIST_HEAD_INIT(alg.cra_list), .cra_u = { .digest = { .dia_digestsize = SHA1_DIGEST_SIZE, .dia_init = sha1_init, .dia_update = sha1_update, .dia_final = sha1_final } } }; static int __init init(void) { return crypto_register_alg(&alg); } static void __exit fini(void) { crypto_unregister_alg(&alg); } module_init(init); module_exit(fini); MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("SHA1 Secure Hash Algorithm"); MODULE_ALIAS("sha1");