+++ /dev/null
-/**********************************************************************
- * gosthash.c *
- * Copyright (c) 2005-2006 Cryptocom LTD *
- * This file is distributed under the same license as OpenSSL *
- * *
- * Implementation of GOST R 34.11-94 hash function *
- * uses on gost89.c and gost89.h Doesn't need OpenSSL *
- **********************************************************************/
-#include <string.h>
-
-#include "gost89.h"
-#include "gosthash.h"
-
-
-/* Use OPENSSL_malloc for memory allocation if compiled with
- * -DOPENSSL_BUILD, and libc malloc otherwise
- */
-#ifndef MYALLOC
-# ifdef OPENSSL_BUILD
-# include <openssl/crypto.h>
-# define MYALLOC(size) OPENSSL_malloc(size)
-# define MYFREE(ptr) OPENSSL_free(ptr)
-# else
-# define MYALLOC(size) malloc(size)
-# define MYFREE(ptr) free(ptr)
-# endif
-#endif
-/* Following functions are various bit meshing routines used in
- * GOST R 34.11-94 algorithms */
-static void swap_bytes (byte *w, byte *k)
- {
- int i,j;
- for (i=0;i<4;i++)
- for (j=0;j<8;j++)
- k[i+4*j]=w[8*i+j];
-
- }
-
-/* was A_A */
-static void circle_xor8 (const byte *w, byte *k)
- {
- byte buf[8];
- int i;
- memcpy(buf,w,8);
- memmove(k,w+8,24);
- for(i=0;i<8;i++)
- k[i+24]=buf[i]^k[i];
- }
-
-/* was R_R */
-static void transform_3 (byte *data)
- {
- unsigned short int acc;
- acc=(data[0]^data[2]^data[4]^data[6]^data[24]^data[30])|
- ((data[1]^data[3]^data[5]^data[7]^data[25]^data[31])<<8);
- memmove(data,data+2,30);
- data[30]=acc&0xff;
- data[31]=acc>>8;
- }
-
-/* Adds blocks of N bytes modulo 2**(8*n). Returns carry*/
-static int add_blocks(int n,byte *left, const byte *right)
- {
- int i;
- int carry=0;
- int sum;
- for (i=0;i<n;i++)
- {
- sum=(int)left[i]+(int)right[i]+carry;
- left[i]=sum & 0xff;
- carry=sum>>8;
- }
- return carry;
- }
-
-/* Xor two sequences of bytes */
-static void xor_blocks (byte *result,const byte *a,const byte *b,size_t len)
- {
- size_t i;
- for (i=0;i<len;i++) result[i]=a[i]^b[i];
- }
-
-/*
- * Calculate H(i+1) = Hash(Hi,Mi)
- * Where H and M are 32 bytes long
- */
-static int hash_step(gost_ctx *c,byte *H,const byte *M)
- {
- byte U[32],W[32],V[32],S[32],Key[32];
- int i;
- /* Compute first key */
- xor_blocks(W,H,M,32);
- swap_bytes(W,Key);
- /* Encrypt first 8 bytes of H with first key*/
- gost_enc_with_key(c,Key,H,S);
- /* Compute second key*/
- circle_xor8(H,U);
- circle_xor8(M,V);
- circle_xor8(V,V);
- xor_blocks(W,U,V,32);
- swap_bytes(W,Key);
- /* encrypt second 8 bytes of H with second key*/
- gost_enc_with_key(c,Key,H+8,S+8);
- /* compute third key */
- circle_xor8(U,U);
- U[31]=~U[31]; U[29]=~U[29]; U[28]=~U[28]; U[24]=~U[24];
- U[23]=~U[23]; U[20]=~U[20]; U[18]=~U[18]; U[17]=~U[17];
- U[14]=~U[14]; U[12]=~U[12]; U[10]=~U[10]; U[ 8]=~U[ 8];
- U[ 7]=~U[ 7]; U[ 5]=~U[ 5]; U[ 3]=~U[ 3]; U[ 1]=~U[ 1];
- circle_xor8(V,V);
- circle_xor8(V,V);
- xor_blocks(W,U,V,32);
- swap_bytes(W,Key);
- /* encrypt third 8 bytes of H with third key*/
- gost_enc_with_key(c,Key,H+16,S+16);
- /* Compute fourth key */
- circle_xor8(U,U);
- circle_xor8(V,V);
- circle_xor8(V,V);
- xor_blocks(W,U,V,32);
- swap_bytes(W,Key);
- /* Encrypt last 8 bytes with fourth key */
- gost_enc_with_key(c,Key,H+24,S+24);
- for (i=0;i<12;i++)
- transform_3(S);
- xor_blocks(S,S,M,32);
- transform_3(S);
- xor_blocks(S,S,H,32);
- for (i=0;i<61;i++)
- transform_3(S);
- memcpy(H,S,32);
- return 1;
- }
-
-/* Initialize gost_hash ctx - cleans up temporary structures and
- * set up substitution blocks
- */
-int init_gost_hash_ctx(gost_hash_ctx *ctx, const gost_subst_block *subst_block)
- {
- memset(ctx,0,sizeof(gost_hash_ctx));
- ctx->cipher_ctx = (gost_ctx *)MYALLOC(sizeof(gost_ctx));
- if (!ctx->cipher_ctx)
- {
- return 0;
- }
- gost_init(ctx->cipher_ctx,subst_block);
- return 1;
- }
-
-/*
- * Free cipher CTX if it is dynamically allocated. Do not use
- * if cipher ctx is statically allocated as in OpenSSL implementation of
- * GOST hash algroritm
- *
- */
-void done_gost_hash_ctx(gost_hash_ctx *ctx)
- {
- /* No need to use gost_destroy, because cipher keys are not really
- * secret when hashing */
- MYFREE(ctx->cipher_ctx);
- }
-
-/*
- * reset state of hash context to begin hashing new message
- */
-int start_hash(gost_hash_ctx *ctx)
- {
- if (!ctx->cipher_ctx) return 0;
- memset(&(ctx->H),0,32);
- memset(&(ctx->S),0,32);
- ctx->len = 0L;
- ctx->left=0;
- return 1;
- }
-
-/*
- * Hash block of arbitrary length
- *
- *
- */
-int hash_block(gost_hash_ctx *ctx,const byte *block, size_t length)
- {
- if (ctx->left)
- {
- /*There are some bytes from previous step*/
- unsigned int add_bytes = 32-ctx->left;
- if (add_bytes>length)
- {
- add_bytes = length;
- }
- memcpy(&(ctx->remainder[ctx->left]),block,add_bytes);
- ctx->left+=add_bytes;
- if (ctx->left<32)
- {
- return 1;
- }
- block+=add_bytes;
- length-=add_bytes;
- hash_step(ctx->cipher_ctx,ctx->H,ctx->remainder);
- add_blocks(32,ctx->S,ctx->remainder);
- ctx->len+=32;
- ctx->left=0;
- }
- while (length>=32)
- {
- hash_step(ctx->cipher_ctx,ctx->H,block);
-
- add_blocks(32,ctx->S,block);
- ctx->len+=32;
- block+=32;
- length-=32;
- }
- if (length)
- {
- memcpy(ctx->remainder,block,ctx->left=length);
- }
- return 1;
- }
-
-/*
- * Compute hash value from current state of ctx
- * state of hash ctx becomes invalid and cannot be used for further
- * hashing.
- */
-int finish_hash(gost_hash_ctx *ctx,byte *hashval)
- {
- byte buf[32];
- byte H[32];
- byte S[32];
- ghosthash_len fin_len=ctx->len;
- byte *bptr;
- memcpy(H,ctx->H,32);
- memcpy(S,ctx->S,32);
- if (ctx->left)
- {
- memset(buf,0,32);
- memcpy(buf,ctx->remainder,ctx->left);
- hash_step(ctx->cipher_ctx,H,buf);
- add_blocks(32,S,buf);
- fin_len+=ctx->left;
- }
- memset(buf,0,32);
- bptr=buf;
- fin_len<<=3; /* Hash length in BITS!!*/
- while(fin_len>0)
- {
- *(bptr++)=(byte)(fin_len&0xFF);
- fin_len>>=8;
- };
- hash_step(ctx->cipher_ctx,H,buf);
- hash_step(ctx->cipher_ctx,H,S);
- memcpy(hashval,H,32);
- return 1;
- }
projects / cassiopeia.git / blobdiff