chrome/browser/resources/cryptotoken/usbsignhandler.js

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 /**
   6  * @fileoverview Implements a sign handler using USB gnubbies.
   7  */
   8 'use strict';
   9
  10 var CORRUPT_sign = false;
  11
  12 /**
  13  * @param {!SignHelperRequest} request The sign request.
  14  * @constructor
  15  * @implements {RequestHandler}
  16  */
  17 function UsbSignHandler(request) {
  18   /** @private {!SignHelperRequest} */
  19   this.request_ = request;
  20
  21   /** @private {boolean} */
  22   this.notified_ = false;
  23   /** @private {boolean} */
  24   this.anyGnubbiesFound_ = false;
  25   /** @private {!Array<!Gnubby>} */
  26   this.notEnrolledGnubbies_ = [];
  27 }
  28
  29 /**
  30  * Default timeout value in case the caller never provides a valid timeout.
  31  * @const
  32  */
  33 UsbSignHandler.DEFAULT_TIMEOUT_MILLIS = 30 * 1000;
  34
  35 /**
  36  * Attempts to run this handler's request.
  37  * @param {RequestHandlerCallback} cb Called with the result of the request and
  38  *     an optional source for the sign result.
  39  * @return {boolean} whether this set of challenges was accepted.
  40  */
  41 UsbSignHandler.prototype.run = function(cb) {
  42   if (this.cb_) {
  43     // Can only handle one request.
  44     return false;
  45   }
  46   /** @private {RequestHandlerCallback} */
  47   this.cb_ = cb;
  48   if (!this.request_.signData || !this.request_.signData.length) {
  49     // Fail a sign request with an empty set of challenges.
  50     return false;
  51   }
  52   var timeoutMillis =
  53       this.request_.timeoutSeconds ?
  54       this.request_.timeoutSeconds * 1000 :
  55       UsbSignHandler.DEFAULT_TIMEOUT_MILLIS;
  56   /** @private {MultipleGnubbySigner} */
  57   this.signer_ = new MultipleGnubbySigner(
  58       false /* forEnroll */,
  59       this.signerCompleted_.bind(this),
  60       this.signerFoundGnubby_.bind(this),
  61       timeoutMillis,
  62       this.request_.logMsgUrl);
  63   return this.signer_.doSign(this.request_.signData);
  64 };
  65
  66
  67 /**
  68  * Called when a MultipleGnubbySigner completes.
  69  * @param {boolean} anyPending Whether any gnubbies are pending.
  70  * @private
  71  */
  72 UsbSignHandler.prototype.signerCompleted_ = function(anyPending) {
  73   if (!this.anyGnubbiesFound_ || anyPending) {
  74     this.notifyError_(DeviceStatusCodes.TIMEOUT_STATUS);
  75   } else if (this.signerError_ !== undefined) {
  76     this.notifyError_(this.signerError_);
  77   } else {
  78     // Do nothing: signerFoundGnubby_ will have returned results from other
  79     // gnubbies.
  80   }
  81 };
  82
  83 /**
  84  * Called when a MultipleGnubbySigner finds a gnubby that has completed signing
  85  * its challenges.
  86  * @param {MultipleSignerResult} signResult Signer result object
  87  * @param {boolean} moreExpected Whether the signer expects to produce more
  88  *     results.
  89  * @private
  90  */
  91 UsbSignHandler.prototype.signerFoundGnubby_ =
  92     function(signResult, moreExpected) {
  93   this.anyGnubbiesFound_ = true;
  94   if (!signResult.code) {
  95     var gnubby = signResult['gnubby'];
  96     var challenge = signResult['challenge'];
  97     var info = new Uint8Array(signResult['info']);
  98     this.notifySuccess_(gnubby, challenge, info);
  99   } else if (signResult.code == DeviceStatusCodes.WRONG_DATA_STATUS) {
 100     var gnubby = signResult['gnubby'];
 101     this.notEnrolledGnubbies_.push(gnubby);
 102     this.sendBogusEnroll_(gnubby);
 103   } else if (!moreExpected) {
 104     // If the signer doesn't expect more results, return the error directly to
 105     // the caller.
 106     this.notifyError_(signResult.code);
 107   } else {
 108     // Record the last error, to report from the complete callback if no other
 109     // eligible gnubbies are found.
 110     /** @private {number} */
 111     this.signerError_ = signResult.code;
 112   }
 113 };
 114
 115 /** @const */
 116 UsbSignHandler.BOGUS_APP_ID_HASH = [
 117     0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41,
 118     0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41,
 119     0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41,
 120     0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41
 121 ];
 122
 123 /** @const */
 124 UsbSignHandler.BOGUS_CHALLENGE_V1 = [
 125     0x04, 0xA2, 0x24, 0x7D, 0x5C, 0x0B, 0x76, 0xF1,
 126     0xDC, 0xCD, 0x44, 0xAF, 0x91, 0x9A, 0xA2, 0x3F,
 127     0x3F, 0xBA, 0x65, 0x9F, 0x06, 0x78, 0x82, 0xFB,
 128     0x93, 0x4B, 0xBF, 0x86, 0x55, 0x95, 0x66, 0x46,
 129     0x76, 0x90, 0xDC, 0xE1, 0xE8, 0x6C, 0x86, 0x86,
 130     0xC3, 0x03, 0x4E, 0x65, 0x52, 0x4C, 0x32, 0x6F,
 131     0xB6, 0x44, 0x0D, 0x50, 0xF9, 0x16, 0xC0, 0xA3,
 132     0xDA, 0x31, 0x4B, 0xD3, 0x3F, 0x94, 0xA5, 0xF1,
 133     0xD3
 134 ];
 135
 136 /** @const */
 137 UsbSignHandler.BOGUS_CHALLENGE_V2 = [
 138     0x42, 0x42, 0x42, 0x42, 0x42, 0x42, 0x42, 0x42,
 139     0x42, 0x42, 0x42, 0x42, 0x42, 0x42, 0x42, 0x42,
 140     0x42, 0x42, 0x42, 0x42, 0x42, 0x42, 0x42, 0x42,
 141     0x42, 0x42, 0x42, 0x42, 0x42, 0x42, 0x42, 0x42
 142 ];
 143
 144 /**
 145  * Sends a bogus enroll command to the not-enrolled gnubby, to force the user
 146  * to tap the gnubby before revealing its state to the caller.
 147  * @param {Gnubby} gnubby The gnubby to "enroll" on.
 148  * @private
 149  */
 150 UsbSignHandler.prototype.sendBogusEnroll_ = function(gnubby) {
 151   var self = this;
 152   gnubby.version(function(rc, opt_data) {
 153     if (rc) {
 154       self.notifyError_(rc);
 155       return;
 156     }
 157     var enrollChallenge;
 158     var version = UTIL_BytesToString(new Uint8Array(opt_data || []));
 159     switch (version) {
 160       case Gnubby.U2F_V1:
 161         enrollChallenge = UsbSignHandler.BOGUS_CHALLENGE_V1;
 162         break;
 163       case Gnubby.U2F_V2:
 164         enrollChallenge = UsbSignHandler.BOGUS_CHALLENGE_V2;
 165         break;
 166       default:
 167         self.notifyError_(DeviceStatusCodes.INVALID_DATA_STATUS);
 168     }
 169     gnubby.enroll(
 170         /** @type {Array<number>} */ (enrollChallenge),
 171         UsbSignHandler.BOGUS_APP_ID_HASH,
 172         self.enrollCallback_.bind(self, gnubby));
 173   });
 174 };
 175
 176 /**
 177  * Called with the result of the (bogus, tap capturing) enroll command.
 178  * @param {Gnubby} gnubby The gnubby "enrolled".
 179  * @param {number} code The result of the enroll command.
 180  * @param {ArrayBuffer=} infoArray Returned data.
 181  * @private
 182  */
 183 UsbSignHandler.prototype.enrollCallback_ = function(gnubby, code, infoArray) {
 184   if (this.notified_)
 185     return;
 186   switch (code) {
 187     case DeviceStatusCodes.WAIT_TOUCH_STATUS:
 188       this.sendBogusEnroll_(gnubby);
 189       return;
 190
 191     case DeviceStatusCodes.OK_STATUS:
 192       // Got a successful enroll => user tapped gnubby.
 193       // Send a WRONG_DATA_STATUS finally. (The gnubby is implicitly closed
 194       // by notifyError_.)
 195       this.notifyError_(DeviceStatusCodes.WRONG_DATA_STATUS);
 196       return;
 197   }
 198 };
 199
 200 /**
 201  * Reports the result of a successful sign operation.
 202  * @param {Gnubby} gnubby Gnubby instance
 203  * @param {SignHelperChallenge} challenge Challenge signed
 204  * @param {Uint8Array} info Result data
 205  * @private
 206  */
 207 UsbSignHandler.prototype.notifySuccess_ = function(gnubby, challenge, info) {
 208   if (this.notified_)
 209     return;
 210   this.notified_ = true;
 211
 212   gnubby.closeWhenIdle();
 213   this.close();
 214
 215   if (CORRUPT_sign) {
 216     CORRUPT_sign = false;
 217     info[info.length - 1] = info[info.length - 1] ^ 0xff;
 218   }
 219   var responseData = {
 220     'appIdHash': B64_encode(challenge['appIdHash']),
 221     'challengeHash': B64_encode(challenge['challengeHash']),
 222     'keyHandle': B64_encode(challenge['keyHandle']),
 223     'signatureData': B64_encode(info)
 224   };
 225   var reply = {
 226     'type': 'sign_helper_reply',
 227     'code': DeviceStatusCodes.OK_STATUS,
 228     'responseData': responseData
 229   };
 230   this.cb_(reply, 'USB');
 231 };
 232
 233 /**
 234  * Reports error to the caller.
 235  * @param {number} code error to report
 236  * @private
 237  */
 238 UsbSignHandler.prototype.notifyError_ = function(code) {
 239   if (this.notified_)
 240     return;
 241   this.notified_ = true;
 242   this.close();
 243   var reply = {
 244     'type': 'sign_helper_reply',
 245     'code': code
 246   };
 247   this.cb_(reply);
 248 };
 249
 250 /**
 251  * Closes the MultipleGnubbySigner, if any.
 252  */
 253 UsbSignHandler.prototype.close = function() {
 254   while (this.notEnrolledGnubbies_.length != 0) {
 255     var gnubby = this.notEnrolledGnubbies_.shift();
 256     gnubby.closeWhenIdle();
 257   }
 258   if (this.signer_) {
 259     this.signer_.close();
 260     this.signer_ = null;
 261   }
 262 };