const emsimp = (f_map_imports, s_tag) => { s_tag += ': '; let AB_HEAP; let ATU8_HEAP; let ATU32_HEAP; // eslint-disable-next-line no-console const console_out = (s_channel, s_out) => console[s_channel](s_tag + s_out.replace(/\0/g, '\n')); let s_error = ''; // for converting bytes to text const utf8 = new TextDecoder(); const h_fds = { // stdout 1(s_out) { console_out('debug', s_out); }, // stderr 2(s_out) { console_out('error', (s_error = s_out)); } }; const g_imports = f_map_imports({ abort() { throw Error(s_tag + (s_error || 'An unknown error occurred')); }, memcpy: (ip_dst, ip_src, nb_size) => ATU8_HEAP.copyWithin(ip_dst, ip_src, ip_src + nb_size), resize(_) { throw Error(s_tag + 'Out of memory'); }, write(i_fd, ip_iov, nl_iovs, ip_written) { // output string let s_out = ''; // track number of bytes read from buffers let cb_read = 0; // each pending iov for (let i_iov = 0; i_iov < nl_iovs; i_iov++) { // start of buffer in memory const ip_start = ATU32_HEAP[ip_iov >> 2]; // size of buffer const nb_len = ATU32_HEAP[(ip_iov + 4) >> 2]; ip_iov += 8; // extract text from buffer s_out += utf8.decode(ATU8_HEAP.subarray(ip_start, ip_start + nb_len)); // update number of bytes read cb_read += nb_len; } // route to fd if (h_fds[i_fd]) { h_fds[i_fd](s_out); } else { // no fd found throw new Error(`libsecp256k1 tried writing to non-open file descriptor: ${i_fd}\n${s_out}`); } // write bytes read ATU32_HEAP[ip_written >> 2] = cb_read; // no error return 0; } }); return [ g_imports, (d_memory) => [ (AB_HEAP = d_memory.buffer), (ATU8_HEAP = new Uint8Array(AB_HEAP)), (ATU32_HEAP = new Uint32Array(AB_HEAP)) ] ]; }; /* * ================================ * GENERATED FILE WARNING * Do not edit this file manually. * ================================ */ const map_wasm_imports = (g_imports) => ({ a: { a: g_imports.abort, f: g_imports.memcpy, d: g_imports.resize, e: () => 52, // _fd_close, c: () => 70, // _fd_seek, b: g_imports.write, }, }); const map_wasm_exports = (g_exports) => ({ malloc: g_exports['i'], free: g_exports['j'], sha256_initialize: g_exports['l'], sha256_write: g_exports['m'], sha256_finalize: g_exports['n'], context_create: g_exports['o'], xonly_pubkey_parse: g_exports['p'], xonly_pubkey_serialize: g_exports['q'], keypair_create: g_exports['r'], keypair_xonly_pub: g_exports['s'], schnorrsig_sign32: g_exports['t'], schnorrsig_verify: g_exports['u'], sbrk: g_exports['sbrk'], memory: g_exports['g'], init: () => g_exports['h'](), }); const S_TAG_BIP340_VERIFY = 'BIP340 verify: '; const S_REASON_INVALID_SK = 'Invalid private key'; const S_REASON_INVALID_PK = 'Invalid public key'; /** * Creates a new instance of the secp256k1 WASM and returns its ES wrapper * @param z_src - a Response containing the WASM binary, a Promise that resolves to one, * or the raw bytes to the WASM binary as a {@link BufferSource} * @returns the wrapper API */ const WasmSecp256k1 = async (z_src) => { // prepare the runtime const [g_imports, f_bind_heap] = emsimp(map_wasm_imports, 'wasm-secp256k1'); // prep the wasm module let d_wasm; // instantiate wasm binary by streaming the response bytes if (z_src instanceof Response || z_src instanceof Promise) { d_wasm = await WebAssembly.instantiateStreaming(z_src, g_imports); } else { // instantiate using raw binary d_wasm = await WebAssembly.instantiate(z_src, g_imports); } // create the libsecp256k1 exports struct const g_wasm = map_wasm_exports(d_wasm.instance.exports); // bind the heap and ref its view(s) const [, ATU8_HEAP] = f_bind_heap(g_wasm.memory); // call into the wasm module's init method g_wasm.init(); const ip_sk = g_wasm.malloc(32 /* ByteLens.PRIVATE_KEY */); const ip_ent = g_wasm.malloc(32 /* ByteLens.NONCE_ENTROPY */); const ip_msg_hash = g_wasm.malloc(32 /* ByteLens.MSG_HASH */); // scratch spaces const ip_pubkey_scratch = g_wasm.malloc(32 /* ByteLens.XONLY_PUBKEY */); const ip_sig_scratch = g_wasm.malloc(64 /* ByteLens.BIP340_SIG */); // library handle: secp256k1_keypair; const ip_keypair = g_wasm.malloc(96 /* ByteLens.KEYPAIR_LIB */); // library handle: secp256k1_xonly_pubkey; const ip_xonly_pubkey = g_wasm.malloc(64 /* ByteLens.XONLY_KEY_LIB */); // library handle: secp256k1_sha256; const ip_sha256 = g_wasm.malloc(104 /* ByteLens.SHA256_LIB */); // create a reusable context const ip_ctx = g_wasm.context_create(513 /* Flags.CONTEXT_SIGN */ | 257 /* Flags.CONTEXT_VERIFY */); // an encoder for hashing strings const utf8 = new TextEncoder(); /** * Puts the given private key into program memory, runs the given callback, then zeroes out the key * @param atu8_sk - the private key * @param f_use - callback to use the key * @returns whatever the callback returns */ const with_keypair = (atu8_sk, f_use) => { // prep callback return let w_return; // in case of any exception.. try { // copy input bytes into place ATU8_HEAP.set(atu8_sk, ip_sk); // instantiate keypair g_wasm.keypair_create(ip_ctx, ip_keypair, ip_sk); // use private key w_return = f_use(); } finally { // zero-out private key and keypair ATU8_HEAP.fill(1, ip_sk, ip_sk + 32 /* ByteLens.PRIVATE_KEY */); ATU8_HEAP.fill(2, ip_keypair, ip_keypair + 96 /* ByteLens.KEYPAIR_LIB */); } // forward result return w_return; }; return { gen_secret_key: () => crypto.getRandomValues(new Uint8Array(32 /* ByteLens.PRIVATE_KEY */)), get_public_key(atu8_sk) { // while using the private key, compute its corresponding public key; from the docs: if (1 /* BinaryResult.SUCCESS */ !== with_keypair(atu8_sk, () => g_wasm.keypair_xonly_pub(ip_ctx, ip_xonly_pubkey, null, ip_keypair))) { throw Error('sk_to_pk: ' + S_REASON_INVALID_SK); } // serialize the public key g_wasm.xonly_pubkey_serialize(ip_ctx, ip_pubkey_scratch, ip_xonly_pubkey); // extract result return ATU8_HEAP.slice(ip_pubkey_scratch, ip_pubkey_scratch + 32 /* ByteLens.XONLY_PUBKEY */); }, sign(atu8_sk, atu8_hash, atu8_ent) { // copy message hash bytes into place ATU8_HEAP.set(atu8_hash, ip_msg_hash); // copy entropy bytes into place if (!atu8_ent && crypto.getRandomValues) { ATU8_HEAP.set(crypto.getRandomValues(new Uint8Array(32)), ip_ent); } // while using the private key, sign the given message hash if (1 /* BinaryResult.SUCCESS */ !== with_keypair(atu8_sk, () => g_wasm.schnorrsig_sign32(ip_ctx, ip_sig_scratch, ip_msg_hash, ip_keypair, ip_ent))) { throw Error('BIP-340 sign: ' + S_REASON_INVALID_SK); } // return serialized signature return ATU8_HEAP.slice(ip_sig_scratch, ip_sig_scratch + 64 /* ByteLens.BIP340_SIG */); }, verify(atu8_signature, atu8_hash, atu8_pk) { // copy signature bytes into place ATU8_HEAP.set(atu8_signature, ip_sig_scratch); // copy message hash bytes into place ATU8_HEAP.set(atu8_hash, ip_msg_hash); // copy pubkey bytes into place ATU8_HEAP.set(atu8_pk, ip_pubkey_scratch); // parse the public key if (1 /* BinaryResult.SUCCESS */ !== g_wasm.xonly_pubkey_parse(ip_ctx, ip_xonly_pubkey, ip_pubkey_scratch)) { throw Error(S_TAG_BIP340_VERIFY + S_REASON_INVALID_PK); } // verify the signature return (1 /* BinaryResult.SUCCESS */ === g_wasm.schnorrsig_verify(ip_ctx, ip_sig_scratch, ip_msg_hash, 32 /* ByteLens.MSG_HASH */, ip_xonly_pubkey)); }, sha256(message) { const ip_message = g_wasm.malloc(message.length); const data = utf8.encode(message); ATU8_HEAP.set(data, ip_message); g_wasm.sha256_initialize(ip_sha256); g_wasm.sha256_write(ip_sha256, ip_message, message.length); g_wasm.sha256_finalize(ip_sha256, ip_msg_hash); return ATU8_HEAP.slice(ip_msg_hash, ip_msg_hash + 32 /* ByteLens.MSG_HASH */); } }; }; export { WasmSecp256k1 as W };