gost_grasshopper_cipher_destroy_ctr,
1,
sizeof(gost_grasshopper_cipher_ctx_ctr),
- 8,
+ /* IV size is set to match full block, to make it responsibility of
+ * user to assign correct values (IV || 0), and to make naive context
+ * copy possible (for software such as openssh) */
+ 16,
false
},
};
static GRASSHOPPER_INLINE void gost_grasshopper_cipher_destroy_ctr(gost_grasshopper_cipher_ctx* c) {
gost_grasshopper_cipher_ctx_ctr* ctx = (gost_grasshopper_cipher_ctx_ctr*) c;
- grasshopper_zero128(&ctx->iv_buffer);
grasshopper_zero128(&ctx->partial_buffer);
}
gost_grasshopper_cipher_ctx_ctr* c = EVP_CIPHER_CTX_get_cipher_data(ctx);
c->c.type = GRASSHOPPER_CIPHER_CTR;
+ EVP_CIPHER_CTX_set_num(ctx, 0);
- grasshopper_zero128(&c->iv_buffer);
grasshopper_zero128(&c->partial_buffer);
return gost_grasshopper_cipher_init(ctx, key, iv, enc);
unsigned char* iv = EVP_CIPHER_CTX_iv_noconst(ctx);
const unsigned char* current_in = in;
unsigned char* current_out = out;
- size_t blocks = inl / GRASSHOPPER_BLOCK_SIZE;
grasshopper_w128_t* currentInputBlock;
grasshopper_w128_t* currentOutputBlock;
+ unsigned int n = EVP_CIPHER_CTX_num(ctx);
size_t lasted;
size_t i;
- memcpy(&c->iv_buffer, iv, 8);
+ while (n && inl) {
+ *(current_out++) = *(current_in++) ^ c->partial_buffer.b[n];
+ --inl;
+ n = (n + 1) % GRASSHOPPER_BLOCK_SIZE;
+ }
+ EVP_CIPHER_CTX_set_num(ctx, n);
+ size_t blocks = inl / GRASSHOPPER_BLOCK_SIZE;
+
+ grasshopper_w128_t* iv_buffer = (grasshopper_w128_t*) iv;
// full parts
for (i = 0; i < blocks; i++) {
currentInputBlock = (grasshopper_w128_t*) current_in;
currentOutputBlock = (grasshopper_w128_t*) current_out;
- grasshopper_encrypt_block(&c->c.encrypt_round_keys, &c->iv_buffer, currentOutputBlock, &c->c.buffer);
+ grasshopper_encrypt_block(&c->c.encrypt_round_keys, iv_buffer, currentOutputBlock, &c->c.buffer);
grasshopper_append128(currentOutputBlock, currentInputBlock);
- ctr128_inc(c->iv_buffer.b);
+ ctr128_inc(iv_buffer->b);
current_in += GRASSHOPPER_BLOCK_SIZE;
current_out += GRASSHOPPER_BLOCK_SIZE;
}
if (lasted > 0) {
currentInputBlock = (grasshopper_w128_t*) current_in;
currentOutputBlock = (grasshopper_w128_t*) current_out;
- grasshopper_encrypt_block(&c->c.encrypt_round_keys, &c->iv_buffer, &c->partial_buffer, &c->c.buffer);
+ grasshopper_encrypt_block(&c->c.encrypt_round_keys, iv_buffer, &c->partial_buffer, &c->c.buffer);
for (i = 0; i < lasted; i++) {
currentOutputBlock->b[i] = c->partial_buffer.b[i] ^ currentInputBlock->b[i];
}
- ctr128_inc(c->iv_buffer.b);
+ EVP_CIPHER_CTX_set_num(ctx, i);
+ ctr128_inc(iv_buffer->b);
}
return 1;
}
+/*
+ * Fixed 128-bit IV implementation make shift regiser redundant.
+ */
static void gost_grasshopper_cnt_next(gost_grasshopper_cipher_ctx_ofb* ctx, grasshopper_w128_t* iv,
grasshopper_w128_t* buf) {
memcpy(&ctx->buffer1, iv, 16);
- ctx->g = ctx->buffer1.b[0] | (ctx->buffer1.b[1] << 8) | (ctx->buffer1.b[2] << 16) |
- ((uint32_t) ctx->buffer1.b[3] << 24);
- ctx->g += 0x01010101;
- ctx->buffer1.b[0] = (unsigned char) (ctx->g & 0xff);
- ctx->buffer1.b[1] = (unsigned char) ((ctx->g >> 8) & 0xff);
- ctx->buffer1.b[2] = (unsigned char) ((ctx->g >> 16) & 0xff);
- ctx->buffer1.b[3] = (unsigned char) ((ctx->g >> 24) & 0xff);
- ctx->g = ctx->buffer1.b[4] | (ctx->buffer1.b[5] << 8) | (ctx->buffer1.b[6] << 16) |
- ((uint32_t) ctx->buffer1.b[7] << 24);
- ctx->go = ctx->g;
- ctx->g += 0x01010104;
- if (ctx->go > ctx->g) { /* overflow */
- ctx->g++;
- }
- ctx->buffer1.b[4] = (unsigned char) (ctx->g & 0xff);
- ctx->buffer1.b[5] = (unsigned char) ((ctx->g >> 8) & 0xff);
- ctx->buffer1.b[6] = (unsigned char) ((ctx->g >> 16) & 0xff);
- ctx->buffer1.b[7] = (unsigned char) ((ctx->g >> 24) & 0xff);
- ctx->g = ctx->buffer1.b[8] | (ctx->buffer1.b[9] << 8) | (ctx->buffer1.b[10] << 16) |
- ((uint32_t) ctx->buffer1.b[11] << 24);
- ctx->go = ctx->g;
- ctx->g += 0x01010107;
- if (ctx->go > ctx->g) { /* overflow */
- ctx->g++;
- }
- ctx->buffer1.b[8] = (unsigned char) (ctx->g & 0xff);
- ctx->buffer1.b[9] = (unsigned char) ((ctx->g >> 8) & 0xff);
- ctx->buffer1.b[10] = (unsigned char) ((ctx->g >> 16) & 0xff);
- ctx->buffer1.b[11] = (unsigned char) ((ctx->g >> 24) & 0xff);
- ctx->g = ctx->buffer1.b[12] | (ctx->buffer1.b[13] << 8) | (ctx->buffer1.b[14] << 16) |
- ((uint32_t) ctx->buffer1.b[15] << 24);
- ctx->go = ctx->g;
- ctx->g += 0x01010110;
- if (ctx->go > ctx->g) { /* overflow */
- ctx->g++;
- }
- ctx->buffer1.b[12] = (unsigned char) (ctx->g & 0xff);
- ctx->buffer1.b[13] = (unsigned char) ((ctx->g >> 8) & 0xff);
- ctx->buffer1.b[14] = (unsigned char) ((ctx->g >> 16) & 0xff);
- ctx->buffer1.b[15] = (unsigned char) ((ctx->g >> 24) & 0xff);
- memcpy(iv, &ctx->buffer1, 16);
grasshopper_encrypt_block(&ctx->c.encrypt_round_keys, &ctx->buffer1, buf, &ctx->c.buffer);
+ memcpy(iv, buf, 16);
}
int gost_grasshopper_cipher_do_ofb(EVP_CIPHER_CTX* ctx, unsigned char* out,