Expose the vdf_sha2_nif to help with debugging a Rust implementation

apps/arweave/c_src/vdf.cpp

@@ -69,26 +69,36 @@ void _vdf_sha2(unsigned char* saltBuffer, unsigned char* seed, unsigned char* ou
 			unsigned char* locIn  = checkpointIdx == 0               ? seed : (outCheckpoint + VDF_SHA_HASH_SIZE*(checkpointIdx-1));
 			unsigned char* locOut = checkpointIdx == checkpointCount ? out  : (outCheckpoint + VDF_SHA_HASH_SIZE*checkpointIdx);
 
-			{
-				SHA256_CTX sha256;
-				SHA256_Init(&sha256);
-				SHA256_Update(&sha256, saltBuffer, SALT_SIZE);
-				SHA256_Update(&sha256, locIn, VDF_SHA_HASH_SIZE); // -1 memcpy
-				SHA256_Final(tempOut, &sha256);
-			}
-			for(int i = 2; i < hashingIterations; i++) {
-				SHA256_CTX sha256;
-				SHA256_Init(&sha256);
-				SHA256_Update(&sha256, saltBuffer, SALT_SIZE);
-				SHA256_Update(&sha256, tempOut, VDF_SHA_HASH_SIZE);
-				SHA256_Final(tempOut, &sha256);
-			}
-			{
-				SHA256_CTX sha256;
-				SHA256_Init(&sha256);
-				SHA256_Update(&sha256, saltBuffer, SALT_SIZE);
-				SHA256_Update(&sha256, tempOut, VDF_SHA_HASH_SIZE);
-				SHA256_Final(locOut, &sha256);
+			if (hashingIterations > 1) {
+				{
+					SHA256_CTX sha256;
+					SHA256_Init(&sha256);
+					SHA256_Update(&sha256, saltBuffer, SALT_SIZE);
+					SHA256_Update(&sha256, locIn, VDF_SHA_HASH_SIZE); // -1 memcpy
+					SHA256_Final(tempOut, &sha256);
+				}
+				for(int i = 2; i < hashingIterations; i++) {
+					SHA256_CTX sha256;
+					SHA256_Init(&sha256);
+					SHA256_Update(&sha256, saltBuffer, SALT_SIZE);
+					SHA256_Update(&sha256, tempOut, VDF_SHA_HASH_SIZE);
+					SHA256_Final(tempOut, &sha256);
+				}
+				{
+					SHA256_CTX sha256;
+					SHA256_Init(&sha256);
+					SHA256_Update(&sha256, saltBuffer, SALT_SIZE);
+					SHA256_Update(&sha256, tempOut, VDF_SHA_HASH_SIZE);
+					SHA256_Final(locOut, &sha256);
+				}
+			} else {
+				{
+					SHA256_CTX sha256;
+					SHA256_Init(&sha256);
+					SHA256_Update(&sha256, saltBuffer, SALT_SIZE);
+					SHA256_Update(&sha256, locIn, VDF_SHA_HASH_SIZE); // -1 memcpy
+					SHA256_Final(locOut, &sha256);
+				}
 			}
 			long_add(saltBuffer, 1);
 		}

apps/arweave/src/ar.erl

@@ -6,7 +6,7 @@
 -behaviour(application).
 
 -export([main/0, main/1, create_wallet/0, create_wallet/1,
-		benchmark_packing/1, benchmark_packing/0, benchmark_vdf/0, start/0,
+		benchmark_packing/1, benchmark_packing/0, benchmark_vdf/0, manual_vdf/0, start/0,
 		start/1, start/2, stop/1, stop_dependencies/0, tests/0, tests/1, tests/2, test_ipfs/0,
 		docs/0, start_for_tests/0, shutdown/1, console/1, console/2]).
 
@@ -721,6 +721,10 @@ benchmark_vdf() ->
 	ar_bench_vdf:run_benchmark(),
 	erlang:halt().
 
+manual_vdf() ->
+	ar_manual_vdf:manual_vdf(),
+	erlang:halt().
+
 shutdown([NodeName]) ->
 	rpc:cast(NodeName, init, stop, []).
 

apps/arweave/src/ar_manual_vdf.erl

@@ -0,0 +1,21 @@
+-module(ar_manual_vdf).
+
+-export([manual_vdf/0]).
+
+-include_lib("arweave/include/ar_vdf.hrl").
+
+manual_vdf() ->
+	PrevOutput = ar_util:decode(<<"W-5B1F7rYIayc_1d3nq3bsLanXNympgA3tkIXOT0EF8">>),
+	StepNumber = 21499625,
+	Salt = ar_vdf:step_number_to_salt_number(StepNumber-1),
+	Salt2 = << Salt:256 >>,
+	CheckpointCount = 0,
+	SkipCheckpointCount = 0,
+	Iterations = 1,
+	{ok, Output, _CheckpointsBuffer} =
+			ar_mine_randomx:vdf_sha2_nif(
+				Salt2, PrevOutput, CheckpointCount, SkipCheckpointCount, Iterations),
+	io:format("~n~n"),
+	io:format("Salt: ~p~n", [ar_util:encode(Salt2)]),
+	io:format("Output: ~p~n", [ar_util:encode(Output)]).
+

bin/manual-vdf

@@ -0,0 +1,17 @@
+#!/usr/bin/env bash
+
+set -e
+
+SCRIPT_DIR="$(dirname "$0")"
+cd "$SCRIPT_DIR/.."
+
+echo Building dependencies...
+./rebar3 compile
+
+ERL="erl"
+# ERL="$ERL_TOP/bin/cerl -debug"
+
+$ERL +MBas aobf +MBlmbcs 512 +A100 +SDio100 +Bi -pa `./rebar3 path` \
+	-config config/sys.config -args_file config/vm.args.dev \
+	-run ar manual_vdf ${@:1}
+