sc_reduce32 poc

CMakeLists.txt

@@ -60,7 +60,7 @@ set(
 ) 
 set(
 	EMCC_LINKER_FLAGS 
-	"--bind -Wall -s MODULARIZE=1 -s 'EXPORT_NAME=\"MyMoneroCoreCpp\"'"#"-s SAFE_HEAP=1 --bind -s WASM=1 -O3 -o ./cryptonote_crypto.emcpp.js -s LEGACY_GL_EMULATION=0  -s GL_UNSAFE_OPTS=0 --pre-js pre-module.js --post-js post-module.js -s ASSERTIONS=1 -s GL_ASSERTIONS=1 -s INVOKE_RUN=0  -std=c++11 -s USE_WEBGL2=1 -s FULL_ES3=1 -s USE_GLFW=3 -s OFFSCREENCANVAS_SUPPORT=1 --preload-file shaders --preload-file extern --use-preload-plugins"
+	"--bind -Wall -s MODULARIZE=1 -s 'EXPORT_NAME=\"MyMoneroCoreCpp\"' -s EXPORTED_FUNCTIONS='[\"_sc_reduce32\"]' -s EXTRA_EXPORTED_RUNTIME_METHODS='[\"ccall\", \"cwrap\"]'"#"-s SAFE_HEAP=1 --bind -s WASM=1 -O3 -o ./cryptonote_crypto.emcpp.js -s LEGACY_GL_EMULATION=0  -s GL_UNSAFE_OPTS=0 --pre-js pre-module.js --post-js post-module.js -s ASSERTIONS=1 -s GL_ASSERTIONS=1 -s INVOKE_RUN=0  -std=c++11 -s USE_WEBGL2=1 -s FULL_ES3=1 -s USE_GLFW=3 -s OFFSCREENCANVAS_SUPPORT=1 --preload-file shaders --preload-file extern --use-preload-plugins"
 )
 
 # extract the filename without an extension (NAME_WE)

src/index.cpp

@@ -8,10 +8,150 @@ float foo(float a, float b, float t)
     return (1 - t) * a + t * b;
 }
 EMSCRIPTEN_BINDINGS(my_module)
-{
+{ // C++ -> JS
     function("foo", &foo);
 }
+extern "C"
+{ // C -> JS
+	/* Common functions */
+	uint64_t load_3(const unsigned char *in) 
+	{
+		uint64_t result;
+		result = (uint64_t) in[0];
+		result |= ((uint64_t) in[1]) << 8;
+		result |= ((uint64_t) in[2]) << 16;
+		return result;
+	}
+	uint64_t load_4(const unsigned char *in)
+	{
+		uint64_t result;
+		result = (uint64_t) in[0];
+		result |= ((uint64_t) in[1]) << 8;
+		result |= ((uint64_t) in[2]) << 16;
+		result |= ((uint64_t) in[3]) << 24;
+		return result;
+	}
+	void sc_reduce32(unsigned char *s) 
+	{
+		printf("calling sc_reduce32 with %s\n", s);
+		// buffer = "returned from sc_reduce32";
+		int64_t s0 = 2097151 & load_3(s);
+		int64_t s1 = 2097151 & (load_4(s + 2) >> 5);
+		int64_t s2 = 2097151 & (load_3(s + 5) >> 2);
+		int64_t s3 = 2097151 & (load_4(s + 7) >> 7);
+		int64_t s4 = 2097151 & (load_4(s + 10) >> 4);
+		int64_t s5 = 2097151 & (load_3(s + 13) >> 1);
+		int64_t s6 = 2097151 & (load_4(s + 15) >> 6);
+		int64_t s7 = 2097151 & (load_3(s + 18) >> 3);
+		int64_t s8 = 2097151 & load_3(s + 21);
+		int64_t s9 = 2097151 & (load_4(s + 23) >> 5);
+		int64_t s10 = 2097151 & (load_3(s + 26) >> 2);
+		int64_t s11 = (load_4(s + 28) >> 7);
+		int64_t s12 = 0;
+		int64_t carry0;
+		int64_t carry1;
+		int64_t carry2;
+		int64_t carry3;
+		int64_t carry4;
+		int64_t carry5;
+		int64_t carry6;
+		int64_t carry7;
+		int64_t carry8;
+		int64_t carry9;
+		int64_t carry10;
+		int64_t carry11;
+
+		carry0 = (s0 + (1<<20)) >> 21; s1 += carry0; s0 -= carry0 << 21;
+		carry2 = (s2 + (1<<20)) >> 21; s3 += carry2; s2 -= carry2 << 21;
+		carry4 = (s4 + (1<<20)) >> 21; s5 += carry4; s4 -= carry4 << 21;
+		carry6 = (s6 + (1<<20)) >> 21; s7 += carry6; s6 -= carry6 << 21;
+		carry8 = (s8 + (1<<20)) >> 21; s9 += carry8; s8 -= carry8 << 21;
+		carry10 = (s10 + (1<<20)) >> 21; s11 += carry10; s10 -= carry10 << 21;
+
+		carry1 = (s1 + (1<<20)) >> 21; s2 += carry1; s1 -= carry1 << 21;
+		carry3 = (s3 + (1<<20)) >> 21; s4 += carry3; s3 -= carry3 << 21;
+		carry5 = (s5 + (1<<20)) >> 21; s6 += carry5; s5 -= carry5 << 21;
+		carry7 = (s7 + (1<<20)) >> 21; s8 += carry7; s7 -= carry7 << 21;
+		carry9 = (s9 + (1<<20)) >> 21; s10 += carry9; s9 -= carry9 << 21;
+		carry11 = (s11 + (1<<20)) >> 21; s12 += carry11; s11 -= carry11 << 21;
+
+		s0 += s12 * 666643;
+		s1 += s12 * 470296;
+		s2 += s12 * 654183;
+		s3 -= s12 * 997805;
+		s4 += s12 * 136657;
+		s5 -= s12 * 683901;
+		s12 = 0;
+
+		carry0 = s0 >> 21; s1 += carry0; s0 -= carry0 << 21;
+		carry1 = s1 >> 21; s2 += carry1; s1 -= carry1 << 21;
+		carry2 = s2 >> 21; s3 += carry2; s2 -= carry2 << 21;
+		carry3 = s3 >> 21; s4 += carry3; s3 -= carry3 << 21;
+		carry4 = s4 >> 21; s5 += carry4; s4 -= carry4 << 21;
+		carry5 = s5 >> 21; s6 += carry5; s5 -= carry5 << 21;
+		carry6 = s6 >> 21; s7 += carry6; s6 -= carry6 << 21;
+		carry7 = s7 >> 21; s8 += carry7; s7 -= carry7 << 21;
+		carry8 = s8 >> 21; s9 += carry8; s8 -= carry8 << 21;
+		carry9 = s9 >> 21; s10 += carry9; s9 -= carry9 << 21;
+		carry10 = s10 >> 21; s11 += carry10; s10 -= carry10 << 21;
+		carry11 = s11 >> 21; s12 += carry11; s11 -= carry11 << 21;
 
+		s0 += s12 * 666643;
+		s1 += s12 * 470296;
+		s2 += s12 * 654183;
+		s3 -= s12 * 997805;
+		s4 += s12 * 136657;
+		s5 -= s12 * 683901;
+
+		carry0 = s0 >> 21; s1 += carry0; s0 -= carry0 << 21;
+		carry1 = s1 >> 21; s2 += carry1; s1 -= carry1 << 21;
+		carry2 = s2 >> 21; s3 += carry2; s2 -= carry2 << 21;
+		carry3 = s3 >> 21; s4 += carry3; s3 -= carry3 << 21;
+		carry4 = s4 >> 21; s5 += carry4; s4 -= carry4 << 21;
+		carry5 = s5 >> 21; s6 += carry5; s5 -= carry5 << 21;
+		carry6 = s6 >> 21; s7 += carry6; s6 -= carry6 << 21;
+		carry7 = s7 >> 21; s8 += carry7; s7 -= carry7 << 21;
+		carry8 = s8 >> 21; s9 += carry8; s8 -= carry8 << 21;
+		carry9 = s9 >> 21; s10 += carry9; s9 -= carry9 << 21;
+		carry10 = s10 >> 21; s11 += carry10; s10 -= carry10 << 21;
+
+		s[0] = s0 >> 0;
+		s[1] = s0 >> 8;
+		s[2] = (s0 >> 16) | (s1 << 5);
+		s[3] = s1 >> 3;
+		s[4] = s1 >> 11;
+		s[5] = (s1 >> 19) | (s2 << 2);
+		s[6] = s2 >> 6;
+		s[7] = (s2 >> 14) | (s3 << 7);
+		s[8] = s3 >> 1;
+		s[9] = s3 >> 9;
+		s[10] = (s3 >> 17) | (s4 << 4);
+		s[11] = s4 >> 4;
+		s[12] = s4 >> 12;
+		s[13] = (s4 >> 20) | (s5 << 1);
+		s[14] = s5 >> 7;
+		s[15] = (s5 >> 15) | (s6 << 6);
+		s[16] = s6 >> 2;
+		s[17] = s6 >> 10;
+		s[18] = (s6 >> 18) | (s7 << 3);
+		s[19] = s7 >> 5;
+		s[20] = s7 >> 13;
+		s[21] = s8 >> 0;
+		s[22] = s8 >> 8;
+		s[23] = (s8 >> 16) | (s9 << 5);
+		s[24] = s9 >> 3;
+		s[25] = s9 >> 11;
+		s[26] = (s9 >> 19) | (s10 << 2);
+		s[27] = s10 >> 6;
+		s[28] = (s10 >> 14) | (s11 << 7);
+		s[29] = s11 >> 1;
+		s[30] = s11 >> 9;
+		s[31] = s11 >> 17;
+
+		printf("ending sc_reduce32 with %s\n", s);
+
+	}
+}
 int main() {
   printf("hello, world!\n");
   return 0;

tests/emjs/MyMoneroCoreCpp.spec.js

@@ -40,6 +40,7 @@ if (!process.env.LISTENING_TO_UNHANDLEDS) {
 }
 //
 const dummy_test_utils = require("./dummy-test-utils.js");
+const dummy_cnUtils_instance = require("./dummy-cnutils").cnUtil()
 
 var public_key =
 	"904e49462268d771cc1649084c35aa1296bfb214880fe2e7f373620a3e2ba597";
@@ -66,7 +67,29 @@ it("has a foo which works", () => {
 		}
 	)
 })
-
+it("can sc_reduce32", () => {
+	dummy_test_utils.OnceModuleReady(
+		function(Module)
+		{
+			var input = dummy_cnUtils_instance.hextobin(public_key);
+			expect(input).toBeTruthy()
+			expect(input.length).toEqual(32)
+			expect(input[0]).toEqual(144)
+			//
+			const mem = Module._malloc(32);
+			expect(mem).toBeTruthy()
+			Module.HEAPU8.set(input, mem);
+			// TODO: assert contents of mem by input
+			//
+			Module.ccall("sc_reduce32", "void", ["number"], [mem]);
+			var output = Module.HEAPU8.subarray(mem, mem + 32);
+			Module._free(mem);
+			//
+			const outputHexString = dummy_cnUtils_instance.bintohex(output)
+			expect(outputHexString).toEqual("3bdba40135ec31594393944d786cd35695bfb214880fe2e7f373620a3e2ba507")
+		}
+	)
+})
 
 
 

tests/emjs/dummy-cnutils.js

@@ -0,0 +1,53 @@
+// Copyright (c) 2014-2018, MyMonero.com
+//
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without modification, are
+// permitted provided that the following conditions are met:
+//
+// 1. Redistributions of source code must retain the above copyright notice, this list of
+//	conditions and the following disclaimer.
+//
+// 2. Redistributions in binary form must reproduce the above copyright notice, this list
+//	of conditions and the following disclaimer in the documentation and/or other
+//	materials provided with the distribution.
+//
+// 3. Neither the name of the copyright holder nor the names of its contributors may be
+//	used to endorse or promote products derived from this software without specific
+//	prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
+// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+// MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
+// THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+// STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
+// THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+//
+var cnUtil = function()
+{
+	this.valid_hex = function(hex) {
+		var exp = new RegExp("[0-9a-fA-F]{" + hex.length + "}");
+		return exp.test(hex);
+	};
+	this.hextobin = function(hex) {
+		if (hex.length % 2 !== 0) throw "Hex string has invalid length!";
+		var res = new Uint8Array(hex.length / 2);
+		for (var i = 0; i < hex.length / 2; ++i) {
+			res[i] = parseInt(hex.slice(i * 2, i * 2 + 2), 16);
+		}
+		return res;
+	}
+	this.bintohex = function(bin) {
+		var out = [];
+		for (var i = 0; i < bin.length; ++i) {
+			out.push(("0" + bin[i].toString(16)).slice(-2));
+		}
+		return out.join("");
+	}
+
+	return this;
+}
+exports.cnUtil = cnUtil;