init

src/derive.js

@@ -0,0 +1,57 @@
+'use strict';
+
+const HDPublicKey = require('hsd/lib/hd/public');
+const Address = require('hsd/lib/primitives/address');
+const fs = require('fs');
+const path = require('path');
+const http = require('http');
+
+const MAX_INDEX = 0x7fffffff;
+
+if (process.argv.length < 3)
+  throw new Error('Usage: node build/hip2-server.js <PORT>');
+const port = process.argv[2];
+
+const xpubFile = path.join(__dirname, '..', 'conf', 'xpub');
+let xpub;
+try {
+  xpub = fs.readFileSync(xpubFile, 'ascii');
+} catch (e) {
+  throw new Error('xpub file missing');
+}
+
+if (xpub === 'xpub6DBMpym6PM3qe7Ug7BwG6zo7dinMMjpk8nmb73czsjkzPTzfQ1d5ZvqDea4uNmMVv1Y9DT6v17GuDL1x2km9FQuKqWMdnrDfRiDNrG1nTMr')
+  throw new Error('Example xpub must not be used! Repalce with your own account xpub.');
+
+const acct = HDPublicKey.fromBase58(xpub);
+const recv = acct.derive(0);
+
+function addr() {
+  const indexFile = path.join(__dirname, '..', 'log', 'hip2-index');
+  let index = 0;
+  try {
+    index = parseInt(fs.readFileSync(indexFile));
+  } catch (e) {
+    ;
+  }
+
+  fs.writeFileSync(indexFile, index + 1);
+
+  // Wow, used all our non-hardened addresses!
+  // Don't roll over the saved index (that way the user knows this has happened)
+  // but start over the address space and reuse addresses starting again at 0.
+  if (index >= MAX_INDEX)
+    index -= MAX_INDEX;
+
+  const pk = recv.derive(index);
+  const addr = Address.fromPubkey(pk.publicKey).toString();
+  return addr;
+}
+
+const requestListener = function (req, res) {
+  res.writeHead(200);
+  res.end(addr());
+};
+
+const server = http.createServer(requestListener);
+server.listen({port});