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wasm vs asm returns different results

See original GitHub issue

import { asmJsInit } from "@polkadot/wasm-crypto-asmjs/data";
import { wasmBytes } from "@polkadot/wasm-crypto-wasm";
import { initWasm } from "@polkadot/wasm-crypto/bridge";
import { secp256k1FromSeed } from "@polkadot/wasm-crypto";
import * as imports from "@polkadot/wasm-crypto/imports";
const wasmPromise = initWasm(wasmBytes, asmJsInit, imports).catch(() => null);
wasmPromise.then(() => {
  console.log(
    secp256k1FromSeed([
      203,
      109,
      249,
      222,
      30,
      252,
      167,
      163,
      153,
      138,
      142,
      173,
      78,
      2,
      21,
      157,
      95,
      169,
      156,
      62,
      13,
      79,
      214,
      67,
      38,
      103,
      57,
      11,
      180,
      114,
      104,
      84,
    ])
  );
});

outputs

[
  203, 109, 249, 222,  30, 252, 167, 163, 153, 138, 142,
  173,  78,   2,  21, 157,  95, 169, 156,  62,  13,  79,
  214,  67,  38, 103,  57,  11, 180, 114, 104,  84,   2,
   10,  16, 145,  52,  31, 229, 102,  75, 250,  23, 130,
  213, 224,  71, 121, 104, 144, 104, 201,  22, 176,  76,
  179, 101, 236,  49,  83, 117,  86, 132, 217, 161
]

however if you just use asm,

const wasmPromise = initWasm([], asmJsInit, imports).catch(() => null);

itll output

[
  203, 109, 249, 222,  30, 252, 167, 163, 153, 138, 142, 173,
   78,   2,  21, 157,  95, 169, 156,  62,  13,  79, 214,  67,
   38, 103,  57,  11, 180, 114, 104,  84,   2,   0,   0,   0,
    0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,
    0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,   0,
    0,   0,   0,   0,   0
]

seems like asm is somehow broken

Issue Analytics

State:
Created 2 years ago
Comments:13 (8 by maintainers)

Top GitHub Comments

1reaction

jacogrcommented, Mar 19, 2022

As an aside …

In the 5.0.1 release, the init would be simpler for asm-only or asm + wasm (intstead of duplicating what is done internally, this would hopefully make is easier for people to adjust) -

// ... or initWasmAsm to have both asm & WASM support
import "@polkadot/wasm-crypto/initOnlyAsm";

import { secp256k1FromSeed, waitReady } from "@polkadot/wasm-crypto";

waitReady().then(() => {
	console.log(
		secp256k1FromSeed(new Uint8Array([
			203, 109, 249, 222, 30, 252, 167, 163, 153, 138, 142,
			173, 78, 2, 21, 157, 95, 169, 156, 62, 13, 79,
			214, 67, 38, 103, 57, 11, 180, 114, 104, 84
		]))
	);
});

1reaction

jacogrcommented, Mar 19, 2022

All the WASM generator deps have been bumped. This had no effect.

This HACK does yield the right results, which I’m certainly not happy with, but I have no other levers to pull here - https://github.com/polkadot-js/wasm/pull/310/commits/e840a6f3d436d0a3b512fd1b2415edd227adc102 (Or rather, no levers that I could find, maybe the wasm2js has an additional cli option that can help?)

https://github.com/polkadot-js/wasm/blob/0dfb491e9d3b5691adb49b40f932773c238f3d03/packages/wasm-crypto/src/bundle.ts#L57-L72

Additionally going to add an assert in @polkadot/util-crypto to ensure that all-zero public keys are not returned. It went in here - https://github.com/polkadot-js/common/blob/2563a0ac3ddfc8de17f907861aa455b3d8db6b49/packages/util-crypto/src/secp256k1/pair/fromSeed.ts#L18-L32

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