bip38: add verify and tests

lib/bip38.js

@@ -223,4 +223,34 @@ Bip38.prototype.decryptECMult = function(encData, passphrase) {
   }
 }
 
+Bip38.prototype.verify = function(encryptedBase58) {
+  var decoded
+  try {
+    decoded = cs.decode(encryptedBase58)
+  } catch (e) {
+    return false
+  }
+
+  if (decoded.length !== 39) return false
+  if (decoded.readUInt8(0) !== 0x01) return false
+
+  var type = decoded.readUInt8(1)
+  var flag = decoded.readUInt8(2)
+
+  // encrypted WIF
+  if (type === 0x42) {
+    if (flag !== 0xc0 && flag !== 0xe0) return false
+
+  // EC mult
+  } else if (type === 0x43) {
+    if ((flag & ~0x24)) return false
+
+  } else {
+    return false
+  }
+
+
+  return true
+}
+
 module.exports = Bip38

test/bip38.test.js

@@ -18,13 +18,21 @@ describe('bip38', function() {
       })
     })
 
-    fixtures.invalid.forEach(function(f) {
+    fixtures.invalid.decrypt.forEach(function(f) {
       it('should throw ' + f.description, function() {
         assert.throws(function() {
           bip38.decrypt(f.bip38, f.passphrase)
         }, new RegExp(f.description, 'i'))
       })
     })
+
+    fixtures.invalid.verify.forEach(function(f) {
+      it('should throw because ' + f.description, function() {
+        assert.throws(function() {
+          bip38.decrypt(f.base58, 'foobar')
+        }, new RegExp(f.exception))
+      })
+    })
   })
 
   describe('encrypt', function() {
@@ -36,4 +44,18 @@ describe('bip38', function() {
       })
     })
   })
+
+  describe('verify', function() {
+    fixtures.valid.forEach(function(f) {
+      it('should return true for ' + f.bip38, function() {
+        assert(bip38.verify(f.bip38))
+      })
+    })
+
+    fixtures.invalid.verify.forEach(function(f) {
+      it('should return false for ' + f.description, function() {
+        assert(!bip38.verify(f.base58))
+      })
+    })
+  })
 })

test/fixtures.json

@@ -71,6 +71,51 @@
       "sequence": 1
     }
   ],
-  "invalid": [
-  ]
+  "invalid": {
+    "decrypt": [],
+    "encrypt": [],
+    "verify": [
+      {
+        "description": "Invalid base58",
+        "exception": "Invalid checksum",
+        "base58": "6PgGWtx25kUg8QWvwuJAgorN6k9FbE25rv5dMRwu5SKMnfpfVe5marXXXX"
+      },
+      {
+        "description": "Length > 39",
+        "exception": "Invalid BIP38 data length",
+        "hex": "0142c000000000000000000000000000000000000000000000000000000000000000000000000000",
+        "base58": "QmxDezFMDL7ExfYmsETsQXAtBbw5YE1CDyA8pm1AGpMpVVUpsVy1yXv4VTL"
+      },
+      {
+        "description": "Length < 39",
+        "exception": "Invalid BIP38 data length",
+        "hex": "0142c00000000000000000000000000000000000000000000000000000000000000000000000",
+        "base58": "2DnNxWcx4Prn8wmjbkvtYGDALsq8BMWxQ33KnXkeH8vrxE41psDLXRmK3"
+      },
+      {
+        "description": "prefix !== 0x01",
+        "exception": "Invalid BIP38 prefix",
+        "hex": "0242c0000000000000000000000000000000000000000000000000000000000000000000000000",
+        "base58": "AfE1YY4Wr2FLAENaH9PVaLRdyk714V4rhwiJMSGyQCGFB3rhGDCs2R7c4s"
+      },
+      {
+        "description": "flag !== 0xc0 && flag !== 0xe0",
+        "exception": "Invalid BIP38 type",
+        "hex": "0101ff000000000000000000000000000000000000000000000000000000000000000000000000",
+        "base58": "5JjnYkbFBmUnhGeDMVhR7aSitLToe1odEfXDBeg4RMK6JmAm9g7rkm7qY3"
+      },
+      {
+        "description": "EC Mult: ~(flag & 0x24)",
+        "exception": "Invalid BIP38 type",
+        "hex": "0101db000000000000000000000000000000000000000000000000000000000000000000000000",
+        "base58": "5JbtdQFKSemRTqMuWrJgSfzE8AX2jdz1KiZuMmuUcv9iXha1s6UarQTciW"
+      },
+      {
+        "description": "EC Mult: ~(flag & 0x24)",
+        "exception": "Invalid BIP38 type",
+        "hex": "010135000000000000000000000000000000000000000000000000000000000000000000000000",
+        "base58": "5HyV7HSYdHUgLf7w36mxMHDPH9muTgUYHEj6cEogKMuV7ae8VRM3VEg56w"
+      }
+    ]
+  }
 }