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root/crypto/sha256_generic.c

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DEFINITIONS

This source file includes following definitions.
  1. Ch
  2. Maj
  3. LOAD_OP
  4. BLEND_OP
  5. sha256_transform
  6. sha224_init
  7. sha256_init
  8. sha256_update
  9. sha256_final
  10. sha224_final
  11. sha256_generic_mod_init
  12. sha256_generic_mod_fini

/*
 * Cryptographic API.
 *
 * SHA-256, as specified in
 * http://csrc.nist.gov/cryptval/shs/sha256-384-512.pdf
 *
 * SHA-256 code by Jean-Luc Cooke <jlcooke@certainkey.com>.
 *
 * Copyright (c) Jean-Luc Cooke <jlcooke@certainkey.com>
 * Copyright (c) Andrew McDonald <andrew@mcdonald.org.uk>
 * Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
 * SHA224 Support Copyright 2007 Intel Corporation <jonathan.lynch@intel.com>
 *
 * 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/types.h>
#include <crypto/sha.h>
#include <asm/byteorder.h>

struct sha256_ctx {
        u32 count[2];
        u32 state[8];
        u8 buf[128];
};

static inline u32 Ch(u32 x, u32 y, u32 z)
{
        return z ^ (x & (y ^ z));
}

static inline u32 Maj(u32 x, u32 y, u32 z)
{
        return (x & y) | (z & (x | y));
}

#define e0(x)       (ror32(x, 2) ^ ror32(x,13) ^ ror32(x,22))
#define e1(x)       (ror32(x, 6) ^ ror32(x,11) ^ ror32(x,25))
#define s0(x)       (ror32(x, 7) ^ ror32(x,18) ^ (x >> 3))
#define s1(x)       (ror32(x,17) ^ ror32(x,19) ^ (x >> 10))

static inline void LOAD_OP(int I, u32 *W, const u8 *input)
{
        W[I] = __be32_to_cpu( ((__be32*)(input))[I] );
}

static inline void BLEND_OP(int I, u32 *W)
{
        W[I] = s1(W[I-2]) + W[I-7] + s0(W[I-15]) + W[I-16];
}

static void sha256_transform(u32 *state, const u8 *input)
{
        u32 a, b, c, d, e, f, g, h, t1, t2;
        u32 W[64];
        int i;

        /* load the input */
        for (i = 0; i < 16; i++)
                LOAD_OP(i, W, input);

        /* now blend */
        for (i = 16; i < 64; i++)
                BLEND_OP(i, W);
    
        /* load the state into our registers */
        a=state[0];  b=state[1];  c=state[2];  d=state[3];
        e=state[4];  f=state[5];  g=state[6];  h=state[7];

        /* now iterate */
        t1 = h + e1(e) + Ch(e,f,g) + 0x428a2f98 + W[ 0];
        t2 = e0(a) + Maj(a,b,c);    d+=t1;    h=t1+t2;
        t1 = g + e1(d) + Ch(d,e,f) + 0x71374491 + W[ 1];
        t2 = e0(h) + Maj(h,a,b);    c+=t1;    g=t1+t2;
        t1 = f + e1(c) + Ch(c,d,e) + 0xb5c0fbcf + W[ 2];
        t2 = e0(g) + Maj(g,h,a);    b+=t1;    f=t1+t2;
        t1 = e + e1(b) + Ch(b,c,d) + 0xe9b5dba5 + W[ 3];
        t2 = e0(f) + Maj(f,g,h);    a+=t1;    e=t1+t2;
        t1 = d + e1(a) + Ch(a,b,c) + 0x3956c25b + W[ 4];
        t2 = e0(e) + Maj(e,f,g);    h+=t1;    d=t1+t2;
        t1 = c + e1(h) + Ch(h,a,b) + 0x59f111f1 + W[ 5];
        t2 = e0(d) + Maj(d,e,f);    g+=t1;    c=t1+t2;
        t1 = b + e1(g) + Ch(g,h,a) + 0x923f82a4 + W[ 6];
        t2 = e0(c) + Maj(c,d,e);    f+=t1;    b=t1+t2;
        t1 = a + e1(f) + Ch(f,g,h) + 0xab1c5ed5 + W[ 7];
        t2 = e0(b) + Maj(b,c,d);    e+=t1;    a=t1+t2;

        t1 = h + e1(e) + Ch(e,f,g) + 0xd807aa98 + W[ 8];
        t2 = e0(a) + Maj(a,b,c);    d+=t1;    h=t1+t2;
        t1 = g + e1(d) + Ch(d,e,f) + 0x12835b01 + W[ 9];
        t2 = e0(h) + Maj(h,a,b);    c+=t1;    g=t1+t2;
        t1 = f + e1(c) + Ch(c,d,e) + 0x243185be + W[10];
        t2 = e0(g) + Maj(g,h,a);    b+=t1;    f=t1+t2;
        t1 = e + e1(b) + Ch(b,c,d) + 0x550c7dc3 + W[11];
        t2 = e0(f) + Maj(f,g,h);    a+=t1;    e=t1+t2;
        t1 = d + e1(a) + Ch(a,b,c) + 0x72be5d74 + W[12];
        t2 = e0(e) + Maj(e,f,g);    h+=t1;    d=t1+t2;
        t1 = c + e1(h) + Ch(h,a,b) + 0x80deb1fe + W[13];
        t2 = e0(d) + Maj(d,e,f);    g+=t1;    c=t1+t2;
        t1 = b + e1(g) + Ch(g,h,a) + 0x9bdc06a7 + W[14];
        t2 = e0(c) + Maj(c,d,e);    f+=t1;    b=t1+t2;
        t1 = a + e1(f) + Ch(f,g,h) + 0xc19bf174 + W[15];
        t2 = e0(b) + Maj(b,c,d);    e+=t1;    a=t1+t2;

        t1 = h + e1(e) + Ch(e,f,g) + 0xe49b69c1 + W[16];
        t2 = e0(a) + Maj(a,b,c);    d+=t1;    h=t1+t2;
        t1 = g + e1(d) + Ch(d,e,f) + 0xefbe4786 + W[17];
        t2 = e0(h) + Maj(h,a,b);    c+=t1;    g=t1+t2;
        t1 = f + e1(c) + Ch(c,d,e) + 0x0fc19dc6 + W[18];
        t2 = e0(g) + Maj(g,h,a);    b+=t1;    f=t1+t2;
        t1 = e + e1(b) + Ch(b,c,d) + 0x240ca1cc + W[19];
        t2 = e0(f) + Maj(f,g,h);    a+=t1;    e=t1+t2;
        t1 = d + e1(a) + Ch(a,b,c) + 0x2de92c6f + W[20];
        t2 = e0(e) + Maj(e,f,g);    h+=t1;    d=t1+t2;
        t1 = c + e1(h) + Ch(h,a,b) + 0x4a7484aa + W[21];
        t2 = e0(d) + Maj(d,e,f);    g+=t1;    c=t1+t2;
        t1 = b + e1(g) + Ch(g,h,a) + 0x5cb0a9dc + W[22];
        t2 = e0(c) + Maj(c,d,e);    f+=t1;    b=t1+t2;
        t1 = a + e1(f) + Ch(f,g,h) + 0x76f988da + W[23];
        t2 = e0(b) + Maj(b,c,d);    e+=t1;    a=t1+t2;

        t1 = h + e1(e) + Ch(e,f,g) + 0x983e5152 + W[24];
        t2 = e0(a) + Maj(a,b,c);    d+=t1;    h=t1+t2;
        t1 = g + e1(d) + Ch(d,e,f) + 0xa831c66d + W[25];
        t2 = e0(h) + Maj(h,a,b);    c+=t1;    g=t1+t2;
        t1 = f + e1(c) + Ch(c,d,e) + 0xb00327c8 + W[26];
        t2 = e0(g) + Maj(g,h,a);    b+=t1;    f=t1+t2;
        t1 = e + e1(b) + Ch(b,c,d) + 0xbf597fc7 + W[27];
        t2 = e0(f) + Maj(f,g,h);    a+=t1;    e=t1+t2;
        t1 = d + e1(a) + Ch(a,b,c) + 0xc6e00bf3 + W[28];
        t2 = e0(e) + Maj(e,f,g);    h+=t1;    d=t1+t2;
        t1 = c + e1(h) + Ch(h,a,b) + 0xd5a79147 + W[29];
        t2 = e0(d) + Maj(d,e,f);    g+=t1;    c=t1+t2;
        t1 = b + e1(g) + Ch(g,h,a) + 0x06ca6351 + W[30];
        t2 = e0(c) + Maj(c,d,e);    f+=t1;    b=t1+t2;
        t1 = a + e1(f) + Ch(f,g,h) + 0x14292967 + W[31];
        t2 = e0(b) + Maj(b,c,d);    e+=t1;    a=t1+t2;

        t1 = h + e1(e) + Ch(e,f,g) + 0x27b70a85 + W[32];
        t2 = e0(a) + Maj(a,b,c);    d+=t1;    h=t1+t2;
        t1 = g + e1(d) + Ch(d,e,f) + 0x2e1b2138 + W[33];
        t2 = e0(h) + Maj(h,a,b);    c+=t1;    g=t1+t2;
        t1 = f + e1(c) + Ch(c,d,e) + 0x4d2c6dfc + W[34];
        t2 = e0(g) + Maj(g,h,a);    b+=t1;    f=t1+t2;
        t1 = e + e1(b) + Ch(b,c,d) + 0x53380d13 + W[35];
        t2 = e0(f) + Maj(f,g,h);    a+=t1;    e=t1+t2;
        t1 = d + e1(a) + Ch(a,b,c) + 0x650a7354 + W[36];
        t2 = e0(e) + Maj(e,f,g);    h+=t1;    d=t1+t2;
        t1 = c + e1(h) + Ch(h,a,b) + 0x766a0abb + W[37];
        t2 = e0(d) + Maj(d,e,f);    g+=t1;    c=t1+t2;
        t1 = b + e1(g) + Ch(g,h,a) + 0x81c2c92e + W[38];
        t2 = e0(c) + Maj(c,d,e);    f+=t1;    b=t1+t2;
        t1 = a + e1(f) + Ch(f,g,h) + 0x92722c85 + W[39];
        t2 = e0(b) + Maj(b,c,d);    e+=t1;    a=t1+t2;

        t1 = h + e1(e) + Ch(e,f,g) + 0xa2bfe8a1 + W[40];
        t2 = e0(a) + Maj(a,b,c);    d+=t1;    h=t1+t2;
        t1 = g + e1(d) + Ch(d,e,f) + 0xa81a664b + W[41];
        t2 = e0(h) + Maj(h,a,b);    c+=t1;    g=t1+t2;
        t1 = f + e1(c) + Ch(c,d,e) + 0xc24b8b70 + W[42];
        t2 = e0(g) + Maj(g,h,a);    b+=t1;    f=t1+t2;
        t1 = e + e1(b) + Ch(b,c,d) + 0xc76c51a3 + W[43];
        t2 = e0(f) + Maj(f,g,h);    a+=t1;    e=t1+t2;
        t1 = d + e1(a) + Ch(a,b,c) + 0xd192e819 + W[44];
        t2 = e0(e) + Maj(e,f,g);    h+=t1;    d=t1+t2;
        t1 = c + e1(h) + Ch(h,a,b) + 0xd6990624 + W[45];
        t2 = e0(d) + Maj(d,e,f);    g+=t1;    c=t1+t2;
        t1 = b + e1(g) + Ch(g,h,a) + 0xf40e3585 + W[46];
        t2 = e0(c) + Maj(c,d,e);    f+=t1;    b=t1+t2;
        t1 = a + e1(f) + Ch(f,g,h) + 0x106aa070 + W[47];
        t2 = e0(b) + Maj(b,c,d);    e+=t1;    a=t1+t2;

        t1 = h + e1(e) + Ch(e,f,g) + 0x19a4c116 + W[48];
        t2 = e0(a) + Maj(a,b,c);    d+=t1;    h=t1+t2;
        t1 = g + e1(d) + Ch(d,e,f) + 0x1e376c08 + W[49];
        t2 = e0(h) + Maj(h,a,b);    c+=t1;    g=t1+t2;
        t1 = f + e1(c) + Ch(c,d,e) + 0x2748774c + W[50];
        t2 = e0(g) + Maj(g,h,a);    b+=t1;    f=t1+t2;
        t1 = e + e1(b) + Ch(b,c,d) + 0x34b0bcb5 + W[51];
        t2 = e0(f) + Maj(f,g,h);    a+=t1;    e=t1+t2;
        t1 = d + e1(a) + Ch(a,b,c) + 0x391c0cb3 + W[52];
        t2 = e0(e) + Maj(e,f,g);    h+=t1;    d=t1+t2;
        t1 = c + e1(h) + Ch(h,a,b) + 0x4ed8aa4a + W[53];
        t2 = e0(d) + Maj(d,e,f);    g+=t1;    c=t1+t2;
        t1 = b + e1(g) + Ch(g,h,a) + 0x5b9cca4f + W[54];
        t2 = e0(c) + Maj(c,d,e);    f+=t1;    b=t1+t2;
        t1 = a + e1(f) + Ch(f,g,h) + 0x682e6ff3 + W[55];
        t2 = e0(b) + Maj(b,c,d);    e+=t1;    a=t1+t2;

        t1 = h + e1(e) + Ch(e,f,g) + 0x748f82ee + W[56];
        t2 = e0(a) + Maj(a,b,c);    d+=t1;    h=t1+t2;
        t1 = g + e1(d) + Ch(d,e,f) + 0x78a5636f + W[57];
        t2 = e0(h) + Maj(h,a,b);    c+=t1;    g=t1+t2;
        t1 = f + e1(c) + Ch(c,d,e) + 0x84c87814 + W[58];
        t2 = e0(g) + Maj(g,h,a);    b+=t1;    f=t1+t2;
        t1 = e + e1(b) + Ch(b,c,d) + 0x8cc70208 + W[59];
        t2 = e0(f) + Maj(f,g,h);    a+=t1;    e=t1+t2;
        t1 = d + e1(a) + Ch(a,b,c) + 0x90befffa + W[60];
        t2 = e0(e) + Maj(e,f,g);    h+=t1;    d=t1+t2;
        t1 = c + e1(h) + Ch(h,a,b) + 0xa4506ceb + W[61];
        t2 = e0(d) + Maj(d,e,f);    g+=t1;    c=t1+t2;
        t1 = b + e1(g) + Ch(g,h,a) + 0xbef9a3f7 + W[62];
        t2 = e0(c) + Maj(c,d,e);    f+=t1;    b=t1+t2;
        t1 = a + e1(f) + Ch(f,g,h) + 0xc67178f2 + W[63];
        t2 = e0(b) + Maj(b,c,d);    e+=t1;    a=t1+t2;

        state[0] += a; state[1] += b; state[2] += c; state[3] += d;
        state[4] += e; state[5] += f; state[6] += g; state[7] += h;

        /* clear any sensitive info... */
        a = b = c = d = e = f = g = h = t1 = t2 = 0;
        memset(W, 0, 64 * sizeof(u32));
}


static void sha224_init(struct crypto_tfm *tfm)
{
        struct sha256_ctx *sctx = crypto_tfm_ctx(tfm);
        sctx->state[0] = SHA224_H0;
        sctx->state[1] = SHA224_H1;
        sctx->state[2] = SHA224_H2;
        sctx->state[3] = SHA224_H3;
        sctx->state[4] = SHA224_H4;
        sctx->state[5] = SHA224_H5;
        sctx->state[6] = SHA224_H6;
        sctx->state[7] = SHA224_H7;
        sctx->count[0] = 0;
        sctx->count[1] = 0;
}

static void sha256_init(struct crypto_tfm *tfm)
{
        struct sha256_ctx *sctx = crypto_tfm_ctx(tfm);
        sctx->state[0] = SHA256_H0;
        sctx->state[1] = SHA256_H1;
        sctx->state[2] = SHA256_H2;
        sctx->state[3] = SHA256_H3;
        sctx->state[4] = SHA256_H4;
        sctx->state[5] = SHA256_H5;
        sctx->state[6] = SHA256_H6;
        sctx->state[7] = SHA256_H7;
        sctx->count[0] = sctx->count[1] = 0;
}

static void sha256_update(struct crypto_tfm *tfm, const u8 *data,
                          unsigned int len)
{
        struct sha256_ctx *sctx = crypto_tfm_ctx(tfm);
        unsigned int i, index, part_len;

        /* Compute number of bytes mod 128 */
        index = (unsigned int)((sctx->count[0] >> 3) & 0x3f);

        /* Update number of bits */
        if ((sctx->count[0] += (len << 3)) < (len << 3)) {
                sctx->count[1]++;
                sctx->count[1] += (len >> 29);
        }

        part_len = 64 - index;

        /* Transform as many times as possible. */
        if (len >= part_len) {
                memcpy(&sctx->buf[index], data, part_len);
                sha256_transform(sctx->state, sctx->buf);

                for (i = part_len; i + 63 < len; i += 64)
                        sha256_transform(sctx->state, &data[i]);
                index = 0;
        } else {
                i = 0;
        }
        
        /* Buffer remaining input */
        memcpy(&sctx->buf[index], &data[i], len-i);
}

static void sha256_final(struct crypto_tfm *tfm, u8 *out)
{
        struct sha256_ctx *sctx = crypto_tfm_ctx(tfm);
        __be32 *dst = (__be32 *)out;
        __be32 bits[2];
        unsigned int index, pad_len;
        int i;
        static const u8 padding[64] = { 0x80, };

        /* Save number of bits */
        bits[1] = cpu_to_be32(sctx->count[0]);
        bits[0] = cpu_to_be32(sctx->count[1]);

        /* Pad out to 56 mod 64. */
        index = (sctx->count[0] >> 3) & 0x3f;
        pad_len = (index < 56) ? (56 - index) : ((64+56) - index);
        sha256_update(tfm, padding, pad_len);

        /* Append length (before padding) */
        sha256_update(tfm, (const u8 *)bits, sizeof(bits));

        /* Store state in digest */
        for (i = 0; i < 8; i++)
                dst[i] = cpu_to_be32(sctx->state[i]);

        /* Zeroize sensitive information. */
        memset(sctx, 0, sizeof(*sctx));
}

static void sha224_final(struct crypto_tfm *tfm, u8 *hash)
{
        u8 D[SHA256_DIGEST_SIZE];

        sha256_final(tfm, D);

        memcpy(hash, D, SHA224_DIGEST_SIZE);
        memset(D, 0, SHA256_DIGEST_SIZE);
}

static struct crypto_alg sha256 = {
        .cra_name       =       "sha256",
        .cra_driver_name=       "sha256-generic",
        .cra_flags      =       CRYPTO_ALG_TYPE_DIGEST,
        .cra_blocksize  =       SHA256_BLOCK_SIZE,
        .cra_ctxsize    =       sizeof(struct sha256_ctx),
        .cra_module     =       THIS_MODULE,
        .cra_alignmask  =       3,
        .cra_list       =       LIST_HEAD_INIT(sha256.cra_list),
        .cra_u          =       { .digest = {
        .dia_digestsize =       SHA256_DIGEST_SIZE,
        .dia_init       =       sha256_init,
        .dia_update     =       sha256_update,
        .dia_final      =       sha256_final } }
};

static struct crypto_alg sha224 = {
        .cra_name       = "sha224",
        .cra_driver_name = "sha224-generic",
        .cra_flags      = CRYPTO_ALG_TYPE_DIGEST,
        .cra_blocksize  = SHA224_BLOCK_SIZE,
        .cra_ctxsize    = sizeof(struct sha256_ctx),
        .cra_module     = THIS_MODULE,
        .cra_alignmask  = 3,
        .cra_list       = LIST_HEAD_INIT(sha224.cra_list),
        .cra_u          = { .digest = {
        .dia_digestsize = SHA224_DIGEST_SIZE,
        .dia_init       = sha224_init,
        .dia_update     = sha256_update,
        .dia_final      = sha224_final } }
};

static int __init sha256_generic_mod_init(void)
{
        int ret = 0;

        ret = crypto_register_alg(&sha224);

        if (ret < 0)
                return ret;

        ret = crypto_register_alg(&sha256);

        if (ret < 0)
                crypto_unregister_alg(&sha224);

        return ret;
}

static void __exit sha256_generic_mod_fini(void)
{
        crypto_unregister_alg(&sha224);
        crypto_unregister_alg(&sha256);
}

module_init(sha256_generic_mod_init);
module_exit(sha256_generic_mod_fini);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("SHA-224 and SHA-256 Secure Hash Algorithm");

MODULE_ALIAS("sha224");
MODULE_ALIAS("sha256");

/* [<][>][^][v][top][bottom][index][help] */

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