--- /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 / openssl-gost / engine.git / blobdiff