1 files changed, 105 insertions, 0 deletions
diff --git a/node_modules/public-encrypt/privateDecrypt.js b/node_modules/public-encrypt/privateDecrypt.js
new file mode 100644
index 0000000..8fc6dfe
--- /dev/null
+++ b/node_modules/public-encrypt/privateDecrypt.js
@@ -0,0 +1,105 @@
+var parseKeys = require('parse-asn1')
+var mgf = require('./mgf')
+var xor = require('./xor')
+var BN = require('bn.js')
+var crt = require('browserify-rsa')
+var createHash = require('create-hash')
+var withPublic = require('./withPublic')
+var Buffer = require('safe-buffer').Buffer
+
+module.exports = function privateDecrypt (privateKey, enc, reverse) {
+  var padding
+  if (privateKey.padding) {
+    padding = privateKey.padding
+  } else if (reverse) {
+    padding = 1
+  } else {
+    padding = 4
+  }
+
+  var key = parseKeys(privateKey)
+  var k = key.modulus.byteLength()
+  if (enc.length > k || new BN(enc).cmp(key.modulus) >= 0) {
+    throw new Error('decryption error')
+  }
+  var msg
+  if (reverse) {
+    msg = withPublic(new BN(enc), key)
+  } else {
+    msg = crt(enc, key)
+  }
+  var zBuffer = Buffer.alloc(k - msg.length)
+  msg = Buffer.concat([zBuffer, msg], k)
+  if (padding === 4) {
+    return oaep(key, msg)
+  } else if (padding === 1) {
+    return pkcs1(key, msg, reverse)
+  } else if (padding === 3) {
+    return msg
+  } else {
+    throw new Error('unknown padding')
+  }
+}
+
+function oaep (key, msg) {
+  var k = key.modulus.byteLength()
+  var iHash = createHash('sha1').update(Buffer.alloc(0)).digest()
+  var hLen = iHash.length
+  if (msg[0] !== 0) {
+    throw new Error('decryption error')
+  }
+  var maskedSeed = msg.slice(1, hLen + 1)
+  var maskedDb = msg.slice(hLen + 1)
+  var seed = xor(maskedSeed, mgf(maskedDb, hLen))
+  var db = xor(maskedDb, mgf(seed, k - hLen - 1))
+  if (compare(iHash, db.slice(0, hLen))) {
+    throw new Error('decryption error')
+  }
+  var i = hLen
+  while (db[i] === 0) {
+    i++
+  }
+  if (db[i++] !== 1) {
+    throw new Error('decryption error')
+  }
+  return db.slice(i)
+}
+
+function pkcs1 (key, msg, reverse) {
+  var p1 = msg.slice(0, 2)
+  var i = 2
+  var status = 0
+  while (msg[i++] !== 0) {
+    if (i >= msg.length) {
+      status++
+      break
+    }
+  }
+  var ps = msg.slice(2, i - 1)
+
+  if ((p1.toString('hex') !== '0002' && !reverse) || (p1.toString('hex') !== '0001' && reverse)) {
+    status++
+  }
+  if (ps.length < 8) {
+    status++
+  }
+  if (status) {
+    throw new Error('decryption error')
+  }
+  return msg.slice(i)
+}
+function compare (a, b) {
+  a = Buffer.from(a)
+  b = Buffer.from(b)
+  var dif = 0
+  var len = a.length
+  if (a.length !== b.length) {
+    dif++
+    len = Math.min(a.length, b.length)
+  }
+  var i = -1
+  while (++i < len) {
+    dif += (a[i] ^ b[i])
+  }
+  return dif
+}