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authorDr. Stephen Henson <steve@openssl.org>2006-09-17 13:00:18 +0000
committerDr. Stephen Henson <steve@openssl.org>2006-09-17 13:00:18 +0000
commita04549cc755408ff2dcab209fd87d3e46f7d662a (patch)
treee4778866a61dddb7fb9ef4465490ad48de919645 /engines/ccgost/gosthash.c
parentbc7535bc7fe30fbba222c316a3957da7d906603b (diff)
GOST public key algorithm ENGINE donated to the OpenSSL by Cryptocom.
Very early version, doesn't do much yet, not even added to the build system.
Diffstat (limited to 'engines/ccgost/gosthash.c')
-rw-r--r--engines/ccgost/gosthash.c256
1 files changed, 256 insertions, 0 deletions
diff --git a/engines/ccgost/gosthash.c b/engines/ccgost/gosthash.c
new file mode 100644
index 0000000000..5978dbabaa
--- /dev/null
+++ b/engines/ccgost/gosthash.c
@@ -0,0 +1,256 @@
+/**********************************************************************
+ * 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);
+ memcpy(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)
+{
+ static 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) {
+ const byte *curptr=block;
+ const byte *barrier=block+(length-32);/* Last byte we can safely hash*/
+ gost_ctx *save_c = ctx->cipher_ctx;
+ if (ctx->left) {
+ /*There are some bytes from previous step*/
+ 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;
+ }
+ if (ctx->left>32) {
+ abort();
+ }
+ curptr=block+add_bytes;
+ hash_step(ctx->cipher_ctx,ctx->H,ctx->remainder);
+ if (save_c!=ctx->cipher_ctx) {
+ abort();
+ }
+ add_blocks(32,ctx->S,ctx->remainder);
+ if (save_c!=ctx->cipher_ctx) {
+ abort();
+ }
+ ctx->len+=32;
+ ctx->left=0;
+ }
+ while (curptr<=barrier)
+ {
+ hash_step(ctx->cipher_ctx,ctx->H,curptr);
+ if (save_c!=ctx->cipher_ctx) {
+ abort();
+ }
+
+ add_blocks(32,ctx->S,curptr);
+ if (save_c!=ctx->cipher_ctx) {
+ abort();
+ }
+ ctx->len+=32;
+ curptr+=32;
+ }
+ if (curptr!=block+length) {
+ ctx->left=block+length-curptr;
+ if (ctx->left>32) {
+ abort();
+ }
+ memcpy(ctx->remainder,curptr,ctx->left);
+ }
+ 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];
+ long long 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++)=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;
+}
+