use gostd for merkle in case of stratum

ccminer.cpp

@@ -1500,6 +1500,9 @@ static bool stratum_gen_work(struct stratum_ctx *sctx, struct work *work)
 		case ALGO_WHIRLCOIN:
 			SHA256((uchar*)sctx->job.coinbase, sctx->job.coinbase_size, (uchar*)merkle_root);
 			break;
+        case ALGO_GOSTD:
+            gostd(merkle_root, sctx->job.coinbase, (int)sctx->job.coinbase_size);
+        break;
 		case ALGO_WHIRLPOOL:
 		default:
 			sha256d(merkle_root, sctx->job.coinbase, (int)sctx->job.coinbase_size);
@@ -1509,6 +1512,11 @@ static bool stratum_gen_work(struct stratum_ctx *sctx, struct work *work)
 		memcpy(merkle_root + 32, sctx->job.merkle[i], 32);
 		if (opt_algo == ALGO_HEAVY || opt_algo == ALGO_MJOLLNIR)
 			heavycoin_hash(merkle_root, merkle_root, 64);
+        if (opt_algo == ALGO_GOSTD)
+        {
+            memcpy(merkle_root + 32, merkle_root, 32);
+            gostd(merkle_root, merkle_root, 64);
+        }
 		else
 			sha256d(merkle_root, merkle_root, 64);
 	}

gost/gost.cu

@@ -21,6 +21,15 @@ extern "C" void gostd_hash(void *output, const void *input)
 	memcpy(output, hash, 32);
 }
 
+extern "C" void gostd(void *output, const void *input, size_t len)
+{
+	unsigned char _ALIGN(64) hash[64];
+
+	sph_gost512(hash, (const void*)input, len);
+	sph_gost256(hash, (const void*)hash, 64);
+
+	memcpy(output, hash, 32);
+}
 
 //#define _DEBUG
 #define _DEBUG_PREFIX "gost"

miner.h

@@ -268,6 +268,8 @@ void sha256_init(uint32_t *state);
 void sha256_transform(uint32_t *state, const uint32_t *block, int swap);
 void sha256d(unsigned char *hash, const unsigned char *data, int len);
 
+void gostd(void *output, const void *input, size_t len);
+
 #define HAVE_SHA256_4WAY 0
 #define HAVE_SHA256_8WAY 0