decred stratum hack with extranonce field

override the coinbase field with the static part of the decred header...

rc.local

@@ -39,6 +39,7 @@ screen -dmS lyra2v2 $STRATUM_DIR/run.sh lyra2v2
 
 screen -dmS blake $STRATUM_DIR/run.sh blake
 screen -dmS vanilla $STRATUM_DIR/run.sh vanilla # blake 8
+screen -dmS decred $STRATUM_DIR/run.sh decred # blake 14
 
 #screen -dmS keccak $STRATUM_DIR/run.sh keccak
 screen -dmS whirlpool $STRATUM_DIR/run.sh whirlpool

stratum/algos/blake.c

@@ -1,10 +1,9 @@
-#include "blake.h"
 #include <stdlib.h>
 #include <stdint.h>
 #include <string.h>
 #include <stdio.h>
 
-#include "../sha3/sph_blake.h"
+#include <sha3/sph_blake.h>
 
 
 void blake_hash(const char* input, char* output, uint32_t len)
@@ -17,3 +16,30 @@ void blake_hash(const char* input, char* output, uint32_t len)
 	sph_blake256(&ctx_blake, input, len);
 	sph_blake256_close(&ctx_blake, output);
 }
+
+static void hexlify(char *hex, const unsigned char *bin, int len)
+{
+	hex[0] = 0;
+	for(int i=0; i < len; i++)
+		sprintf(hex+strlen(hex), "%02x", bin[i]);
+}
+
+void decred_hash(const char* input, char* output, uint32_t len)
+{
+	sph_blake256_context ctx_blake;
+
+	sph_blake256_set_rounds(14);
+
+	uint32_t* in = (uint32_t*) input;
+	fprintf(stderr, "decred input len=%u n=%08x %08x %08x %08x\n",
+		len, in[35], in[36], in[37], in[38]);
+	if (len > 180) len  = 180;
+
+	//char hex[512];
+	//hexlify(hex, input, len);
+	//fprintf(stderr, "decred %s\n", hex);
+
+	sph_blake256_init(&ctx_blake);
+	sph_blake256(&ctx_blake, input, len);
+	sph_blake256_close(&ctx_blake, output);
+}

stratum/algos/blake.h

@@ -8,6 +8,7 @@ extern "C" {
 #include <stdint.h>
 
 void blake_hash(const char* input, char* output, uint32_t len);
+void decred_hash(const char* input, char* output, uint32_t len);
 
 #ifdef __cplusplus
 }

stratum/client.cpp

@@ -35,6 +35,14 @@ bool client_subscribe(YAAMP_CLIENT *client, json_value *json_params)
 	strcpy(client->extranonce1, client->extranonce1_default);
 	client->extranonce2size = client->extranonce2size_default;
 
+	// decred uses an extradata field in block header, 2 first uint32 are set by the miner
+	if (g_current_algo->name && !strcmp(g_current_algo->name,"decred")) {
+		memset(client->extranonce1, '0', sizeof(client->extranonce1));
+		memcpy(&client->extranonce1[16], client->extranonce1_default, YAAMP_EXTRANONCE2_SIZE*2);
+		client->extranonce1[24] = '\0';
+		client->extranonce2size = client->extranonce2size_default = 12;
+	}
+
 	get_random_key(client->notify_id);
 
 	if(json_params->u.array.length>0)

stratum/client_submit.cpp

@@ -44,6 +44,79 @@ void build_submit_values(YAAMP_JOB_VALUES *submitvalues, YAAMP_JOB_TEMPLATE *tem
 	string_be(submitvalues->hash_hex, submitvalues->hash_be);
 }
 
+/////////////////////////////////////////////
+
+static void create_decred_header(YAAMP_JOB_TEMPLATE *templ, YAAMP_JOB_VALUES *out,
+	const char *ntime, const char *nonce, const char *nonce2)
+{
+	struct __attribute__((__packed__)) {
+		uint32_t version;
+		char prevblock[32];
+		char merkleroot[32];
+		char stakeroot[32];
+		uint16_t votebits;
+		char finalstate[6];
+		uint16_t voters;
+		uint8_t freshstake;
+		uint8_t revoc;
+		uint32_t poolsize;
+		uint32_t nbits;
+		uint64_t sbits;
+		uint32_t height;
+		uint32_t size;
+		uint32_t ntime;
+		uint32_t nonce;
+		unsigned char extra[36];
+	} header;
+
+	memcpy(&header, templ->header, sizeof(header));
+
+	memset(header.extra, 0, 36);
+	sscanf(nonce, "%08x", &header.nonce);
+	binlify(header.extra, (const char*) nonce2);
+
+	hexlify(out->header, (const unsigned char*) &header, 192);
+	memcpy(out->header_bin, &header, sizeof(header));
+}
+
+void build_submit_values_decred(YAAMP_JOB_VALUES *submitvalues, YAAMP_JOB_TEMPLATE *templ,
+	const char *nonce1, const char *nonce2, const char *ntime, const char *nonce)
+{
+	sprintf(submitvalues->coinbase, "%s%s%s%s", templ->coinb1, nonce1, nonce2, templ->coinb2);
+	int coinbase_len = strlen(submitvalues->coinbase);
+
+	unsigned char coinbase_bin[1024];
+	memset(coinbase_bin, 0, 1024);
+	binlify(coinbase_bin, submitvalues->coinbase);
+
+	char doublehash[128];
+	memset(doublehash, 0, 128);
+
+	// some (old) wallet/algos need a simple SHA256 (blakecoin, whirlcoin, groestlcoin...)
+	YAAMP_HASH_FUNCTION merkle_hash = sha256_double_hash_hex;
+	if (g_current_algo->merkle_func)
+		merkle_hash = g_current_algo->merkle_func;
+	merkle_hash((char *)coinbase_bin, doublehash, coinbase_len/2);
+
+	string merkleroot = merkle_with_first(templ->txsteps, doublehash);
+	ser_string_be(merkleroot.c_str(), submitvalues->merkleroot_be, 8);
+
+#ifdef MERKLE_DEBUGLOG
+	printf("merkle root %s\n", merkleroot.c_str());
+#endif
+	create_decred_header(templ, submitvalues, ntime, nonce, nonce2);
+
+	//ser_string_be(submitvalues->header, submitvalues->header_be, 20);
+	//binlify(submitvalues->header_bin, submitvalues->header_be);
+
+//	printf("%s\n", submitvalues->header_be);
+	int header_len = strlen(submitvalues->header)/2;
+	g_current_algo->hash_function((char *)submitvalues->header_bin, (char *)submitvalues->hash_bin, header_len);
+
+	hexlify(submitvalues->hash_hex, submitvalues->hash_bin, 32);
+	string_be(submitvalues->hash_hex, submitvalues->hash_be);
+}
+
 /////////////////////////////////////////////////////////////////////////////////
 
 void client_do_submit(YAAMP_CLIENT *client, YAAMP_JOB *job, YAAMP_JOB_VALUES *submitvalues, char *extranonce2, char *ntime, char *nonce)
@@ -286,7 +359,10 @@ bool client_submit(YAAMP_CLIENT *client, json_value *json_params)
 	YAAMP_JOB_VALUES submitvalues;
 	memset(&submitvalues, 0, sizeof(submitvalues));
 
-	build_submit_values(&submitvalues, templ, client->extranonce1, extranonce2, ntime, nonce);
+	if(job->coind && !strcmp(job->coind->symbol,"DCR"))
+		build_submit_values_decred(&submitvalues, templ, client->extranonce1, extranonce2, ntime, nonce);
+	else
+		build_submit_values(&submitvalues, templ, client->extranonce1, extranonce2, ntime, nonce);
 
 	// minimum hash diff begins with 0000, for all...
 	uint8_t pfx = submitvalues.hash_bin[30] | submitvalues.hash_bin[31];

stratum/coinbase.cpp

@@ -196,6 +196,12 @@ void coinbase_create(YAAMP_COIND *coind, YAAMP_JOB_TEMPLATE *templ, json_value *
 	job_pack_tx(coind, templ->coinb2, available, NULL);
 	strcat(templ->coinb2, "00000000"); // locktime
 
+	if(!strcmp(coind->symbol, "DCR")) {
+		// bypass coinbase and merkle for now... sent without changes
+		const unsigned char *hdr = (unsigned char *) &templ->header[36];
+		hexlify(templ->coinb1, hdr, 192 - 80);
+	}
+
 	//if(coind->txmessage)
 	//	strcat(templ->coinb2, "00");
 

stratum/coind.cpp

@@ -150,7 +150,7 @@ void coind_init(YAAMP_COIND *coind)
 	yaamp_create_mutex(&coind->mutex);
 
 	coind->rpc.curl = 0;
-	if(!strcmp(coind->symbol, "DCR") || !strcmp(coind->symbol, "DCRD")) {
+	if(!strcmp(coind->symbol, "DCR")) {
 		coind->rpc.curl = 1;
 		sprintf(account, "default");
 	}

stratum/coind_template.cpp

@@ -114,7 +114,7 @@ static int coind_parse_decred_header(YAAMP_JOB_TEMPLATE *templ, json_value *json
 		uint32_t size;
 		uint32_t ntime;
 		uint32_t nonce;
-		char extra[36];
+		unsigned char extra[36];
 	} header;
 
 	const char *header_hex = json_get_string(json, "header");
@@ -125,7 +125,7 @@ static int coind_parse_decred_header(YAAMP_JOB_TEMPLATE *templ, json_value *json
 	binlify((unsigned char*) &header, header_hex);
 
 	templ->height = header.height;
-	sprintf(templ->version, "%08x", header.version);
+	sprintf(templ->version, "%08x", bswap32(header.version));
 	sprintf(templ->ntime, "%08x", header.ntime);
 	sprintf(templ->nbits, "%08x", header.nbits);
 
@@ -134,6 +134,9 @@ static int coind_parse_decred_header(YAAMP_JOB_TEMPLATE *templ, json_value *json
 	for(int i=0; i < 32; i++)
 		sprintf(templ->prevhash_hex + (i*2), "%02x", (uint8_t) header.prevblock[31-i]);
 
+	// store all other stuff
+	memcpy(templ->header, &header, sizeof(header));
+
 	return 0;
 }
 
@@ -192,7 +195,7 @@ YAAMP_JOB_TEMPLATE *coind_create_template(YAAMP_COIND *coind)
 	const char *flags = json_get_string(json_coinbaseaux, "flags");
 	strcpy(templ->flags, flags ? flags : "");
 
-	if (!strcmp(coind->symbol, "DCR") || !strcmp(coind->symbol, "DCRD")) {
+	if (!strcmp(coind->symbol, "DCR")) {
 		coind_parse_decred_header(templ, json_result);
 	}
 	else

stratum/job.cpp

@@ -89,6 +89,13 @@ static bool job_assign_client(YAAMP_JOB *job, YAAMP_CLIENT *client, double maxha
 		strcpy(client->extranonce1, client->extranonce1_default);
 		client->extranonce2size = client->extranonce2size_default;
 
+		// decred uses an extradata field in block header, 2 first uint32 are set by the miner
+		if (g_current_algo->name && !strcmp(g_current_algo->name,"decred")) {
+			memset(client->extranonce1, '0', sizeof(client->extranonce1));
+			memcpy(&client->extranonce1[16], client->extranonce1_default, 8);
+			client->extranonce1[24] = '\0';
+		}
+
 		client->difficulty_remote = 0;
 		client->jobid_locked = 0;
 	}

stratum/job.h

@@ -45,6 +45,8 @@ struct YAAMP_JOB_TEMPLATE
 	char coinb1[4*1024];
 	char coinb2[4*1024];
 
+	char header[256];
+
 	int auxs_size;
 	YAAMP_COIND_AUX *auxs[MAX_AUXS];
 };

stratum/stratum.cpp

@@ -99,6 +99,7 @@ YAAMP_ALGO g_algos[] =
 	{"blake", blake_hash, 1, 0 },
 	{"blakecoin", blakecoin_hash, 0x100, 0, sha256_hash_hex },
 	{"vanilla", blakecoin_hash, 1, 0 },
+	{"decred", decred_hash, 1, 0 },
 
 	{"fresh", fresh_hash, 0x100, 0, 0},
 	{"quark", quark_hash, 1, 0, 0},