/* * Cryptographic API. * * MD5 Message Digest Algorithm (RFC1321). * * Derived from cryptoapi implementation, originally based on the * public domain implementation written by Colin Plumb in 1993. * * Copyright (c) Cryptoapi developers. * Copyright (c) 2002 James Morris <jmorris@intercode.com.au> * * 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 <crypto/internal/hash.h> #include <crypto/md5.h> #include <linux/init.h> #include <linux/module.h> #include <linux/string.h> #include <linux/types.h> #include <linux/cryptohash.h> #include <asm/byteorder.h> /* XXX: this stuff can be optimized */ static inline void le32_to_cpu_array(u32 *buf, unsigned int words) { while (words--) { __le32_to_cpus(buf); buf++; } } static inline void cpu_to_le32_array(u32 *buf, unsigned int words) { while (words--) { __cpu_to_le32s(buf); buf++; } } static inline void md5_transform_helper(struct md5_state *ctx) { le32_to_cpu_array(ctx->block, sizeof(ctx->block) / sizeof(u32)); md5_transform(ctx->hash, ctx->block); } static int md5_init(struct shash_desc *desc) { struct md5_state *mctx = shash_desc_ctx(desc); mctx->hash[0] = MD5_H0; mctx->hash[1] = MD5_H1; mctx->hash[2] = MD5_H2; mctx->hash[3] = MD5_H3; mctx->byte_count = 0; return 0; } static int md5_update(struct shash_desc *desc, const u8 *data, unsigned int len) { struct md5_state *mctx = shash_desc_ctx(desc); const u32 avail = sizeof(mctx->block) - (mctx->byte_count & 0x3f); mctx->byte_count += len; if (avail > len) { memcpy((char *)mctx->block + (sizeof(mctx->block) - avail), data, len); return 0; } memcpy((char *)mctx->block + (sizeof(mctx->block) - avail), data, avail); md5_transform_helper(mctx); data += avail; len -= avail; while (len >= sizeof(mctx->block)) { memcpy(mctx->block, data, sizeof(mctx->block)); md5_transform_helper(mctx); data += sizeof(mctx->block); len -= sizeof(mctx->block); } memcpy(mctx->block, data, len); return 0; } static int md5_final(struct shash_desc *desc, u8 *out) { struct md5_state *mctx = shash_desc_ctx(desc); const unsigned int offset = mctx->byte_count & 0x3f; char *p = (char *)mctx->block + offset; int padding = 56 - (offset + 1); *p++ = 0x80; if (padding < 0) { memset(p, 0x00, padding + sizeof (u64)); md5_transform_helper(mctx); p = (char *)mctx->block; padding = 56; } memset(p, 0, padding); mctx->block[14] = mctx->byte_count << 3; mctx->block[15] = mctx->byte_count >> 29; le32_to_cpu_array(mctx->block, (sizeof(mctx->block) - sizeof(u64)) / sizeof(u32)); md5_transform(mctx->hash, mctx->block); cpu_to_le32_array(mctx->hash, sizeof(mctx->hash) / sizeof(u32)); memcpy(out, mctx->hash, sizeof(mctx->hash)); memset(mctx, 0, sizeof(*mctx)); return 0; } static int md5_export(struct shash_desc *desc, void *out) { struct md5_state *ctx = shash_desc_ctx(desc); memcpy(out, ctx, sizeof(*ctx)); return 0; } static int md5_import(struct shash_desc *desc, const void *in) { struct md5_state *ctx = shash_desc_ctx(desc); memcpy(ctx, in, sizeof(*ctx)); return 0; } static struct shash_alg alg = { .digestsize = MD5_DIGEST_SIZE, .init = md5_init, .update = md5_update, .final = md5_final, .export = md5_export, .import = md5_import, .descsize = sizeof(struct md5_state), .statesize = sizeof(struct md5_state), .base = { .cra_name = "md5", .cra_flags = CRYPTO_ALG_TYPE_SHASH, .cra_blocksize = MD5_HMAC_BLOCK_SIZE, .cra_module = THIS_MODULE, } }; static int __init md5_mod_init(void) { return crypto_register_shash(&alg); } static void __exit md5_mod_fini(void) { crypto_unregister_shash(&alg); } module_init(md5_mod_init); module_exit(md5_mod_fini); MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("MD5 Message Digest Algorithm"); MODULE_ALIAS_CRYPTO("md5");