"use strict";

var _interopRequireDefault = require("@babel/runtime/helpers/interopRequireDefault");

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.SAS = void 0;

var _Base = require("./Base");

var _anotherJson = _interopRequireDefault(require("another-json"));

var _Error = require("./Error");

var _logger = require("../../logger");

/*
Copyright 2018 New Vector Ltd

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/

/**
 * Short Authentication String (SAS) verification.
 * @module crypto/verification/SAS
 */
const START_TYPE = "m.key.verification.start";
const EVENTS = ["m.key.verification.accept", "m.key.verification.key", "m.key.verification.mac"];
let olmutil;
const newMismatchedSASError = (0, _Error.errorFactory)("m.mismatched_sas", "Mismatched short authentication string");
const newMismatchedCommitmentError = (0, _Error.errorFactory)("m.mismatched_commitment", "Mismatched commitment");

function generateDecimalSas(sasBytes) {
  /**
   *      +--------+--------+--------+--------+--------+
   *      | Byte 0 | Byte 1 | Byte 2 | Byte 3 | Byte 4 |
   *      +--------+--------+--------+--------+--------+
   * bits: 87654321 87654321 87654321 87654321 87654321
   *       \____________/\_____________/\____________/
   *         1st number    2nd number     3rd number
   */
  return [(sasBytes[0] << 5 | sasBytes[1] >> 3) + 1000, ((sasBytes[1] & 0x7) << 10 | sasBytes[2] << 2 | sasBytes[3] >> 6) + 1000, ((sasBytes[3] & 0x3f) << 7 | sasBytes[4] >> 1) + 1000];
}

const emojiMapping = [["🐶", "dog"], //  0
["🐱", "cat"], //  1
["🦁", "lion"], //  2
["🐎", "horse"], //  3
["🦄", "unicorn"], //  4
["🐷", "pig"], //  5
["🐘", "elephant"], //  6
["🐰", "rabbit"], //  7
["🐼", "panda"], //  8
["🐓", "rooster"], //  9
["🐧", "penguin"], // 10
["🐢", "turtle"], // 11
["🐟", "fish"], // 12
["🐙", "octopus"], // 13
["🦋", "butterfly"], // 14
["🌷", "flower"], // 15
["🌳", "tree"], // 16
["🌵", "cactus"], // 17
["🍄", "mushroom"], // 18
["🌏", "globe"], // 19
["🌙", "moon"], // 20
["☁️", "cloud"], // 21
["🔥", "fire"], // 22
["🍌", "banana"], // 23
["🍎", "apple"], // 24
["🍓", "strawberry"], // 25
["🌽", "corn"], // 26
["🍕", "pizza"], // 27
["🎂", "cake"], // 28
["❤️", "heart"], // 29
["🙂", "smiley"], // 30
["🤖", "robot"], // 31
["🎩", "hat"], // 32
["👓", "glasses"], // 33
["🔧", "spanner"], // 34
["🎅", "santa"], // 35
["👍", "thumbs up"], // 36
["☂️", "umbrella"], // 37
["⌛", "hourglass"], // 38
["⏰", "clock"], // 39
["🎁", "gift"], // 40
["💡", "light bulb"], // 41
["📕", "book"], // 42
["✏️", "pencil"], // 43
["📎", "paperclip"], // 44
["✂️", "scissors"], // 45
["🔒", "lock"], // 46
["🔑", "key"], // 47
["🔨", "hammer"], // 48
["☎️", "telephone"], // 49
["🏁", "flag"], // 50
["🚂", "train"], // 51
["🚲", "bicycle"], // 52
["✈️", "aeroplane"], // 53
["🚀", "rocket"], // 54
["🏆", "trophy"], // 55
["⚽", "ball"], // 56
["🎸", "guitar"], // 57
["🎺", "trumpet"], // 58
["🔔", "bell"], // 59
["⚓️", "anchor"], // 60
["🎧", "headphones"], // 61
["📁", "folder"], // 62
["📌", "pin"] // 63
];

function generateEmojiSas(sasBytes) {
  const emojis = [// just like base64 encoding
  sasBytes[0] >> 2, (sasBytes[0] & 0x3) << 4 | sasBytes[1] >> 4, (sasBytes[1] & 0xf) << 2 | sasBytes[2] >> 6, sasBytes[2] & 0x3f, sasBytes[3] >> 2, (sasBytes[3] & 0x3) << 4 | sasBytes[4] >> 4, (sasBytes[4] & 0xf) << 2 | sasBytes[5] >> 6];
  return emojis.map(num => emojiMapping[num]);
}

const sasGenerators = {
  decimal: generateDecimalSas,
  emoji: generateEmojiSas
};

function generateSas(sasBytes, methods) {
  const sas = {};

  for (const method of methods) {
    if (method in sasGenerators) {
      sas[method] = sasGenerators[method](sasBytes);
    }
  }

  return sas;
}

const macMethods = {
  "hkdf-hmac-sha256": "calculate_mac",
  "hmac-sha256": "calculate_mac_long_kdf"
};

function calculateMAC(olmSAS, method) {
  return function (...args) {
    const macFunction = olmSAS[macMethods[method]];
    const mac = macFunction.apply(olmSAS, args);

    _logger.logger.log("SAS calculateMAC:", method, args, mac);

    return mac;
  };
}

const calculateKeyAgreement = {
  "curve25519-hkdf-sha256": function (sas, olmSAS, bytes) {
    const ourInfo = `${sas._baseApis.getUserId()}|${sas._baseApis.deviceId}|` + `${sas.ourSASPubKey}|`;
    const theirInfo = `${sas.userId}|${sas.deviceId}|${sas.theirSASPubKey}|`;
    const sasInfo = "MATRIX_KEY_VERIFICATION_SAS|" + (sas.initiatedByMe ? ourInfo + theirInfo : theirInfo + ourInfo) + sas._channel.transactionId;
    return olmSAS.generate_bytes(sasInfo, bytes);
  },
  "curve25519": function (sas, olmSAS, bytes) {
    const ourInfo = `${sas._baseApis.getUserId()}${sas._baseApis.deviceId}`;
    const theirInfo = `${sas.userId}${sas.deviceId}`;
    const sasInfo = "MATRIX_KEY_VERIFICATION_SAS" + (sas.initiatedByMe ? ourInfo + theirInfo : theirInfo + ourInfo) + sas._channel.transactionId;
    return olmSAS.generate_bytes(sasInfo, bytes);
  }
};
/* lists of algorithms/methods that are supported.  The key agreement, hashes,
 * and MAC lists should be sorted in order of preference (most preferred
 * first).
 */

const KEY_AGREEMENT_LIST = ["curve25519-hkdf-sha256", "curve25519"];
const HASHES_LIST = ["sha256"];
const MAC_LIST = ["hkdf-hmac-sha256", "hmac-sha256"];
const SAS_LIST = Object.keys(sasGenerators);
const KEY_AGREEMENT_SET = new Set(KEY_AGREEMENT_LIST);
const HASHES_SET = new Set(HASHES_LIST);
const MAC_SET = new Set(MAC_LIST);
const SAS_SET = new Set(SAS_LIST);

function intersection(anArray, aSet) {
  return anArray instanceof Array ? anArray.filter(x => aSet.has(x)) : [];
}
/**
 * @alias module:crypto/verification/SAS
 * @extends {module:crypto/verification/Base}
 */


class SAS extends _Base.VerificationBase {
  static get NAME() {
    return "m.sas.v1";
  }

  get events() {
    return EVENTS;
  }

  async _doVerification() {
    await global.Olm.init();
    olmutil = olmutil || new global.Olm.Utility(); // make sure user's keys are downloaded

    await this._baseApis.downloadKeys([this.userId]);
    let retry = false;

    do {
      try {
        if (this.initiatedByMe) {
          return await this._doSendVerification();
        } else {
          return await this._doRespondVerification();
        }
      } catch (err) {
        if (err instanceof _Base.SwitchStartEventError) {
          // this changes what initiatedByMe returns
          this.startEvent = err.startEvent;
          retry = true;
        } else {
          throw err;
        }
      }
    } while (retry);
  }

  canSwitchStartEvent(event) {
    if (event.getType() !== START_TYPE) {
      return false;
    }

    const content = event.getContent();
    return content && content.method === SAS.NAME && this._waitingForAccept;
  }

  async _sendStart() {
    const startContent = this._channel.completeContent(START_TYPE, {
      method: SAS.NAME,
      from_device: this._baseApis.deviceId,
      key_agreement_protocols: KEY_AGREEMENT_LIST,
      hashes: HASHES_LIST,
      message_authentication_codes: MAC_LIST,
      // FIXME: allow app to specify what SAS methods can be used
      short_authentication_string: SAS_LIST
    });

    await this._channel.sendCompleted(START_TYPE, startContent);
    return startContent;
  }

  async _doSendVerification() {
    this._waitingForAccept = true;
    let startContent;

    if (this.startEvent) {
      startContent = this._channel.completedContentFromEvent(this.startEvent);
    } else {
      startContent = await this._sendStart();
    } // we might have switched to a different start event,
    // but was we didn't call _waitForEvent there was no
    // call that could throw yet. So check manually that
    // we're still on the initiator side


    if (!this.initiatedByMe) {
      throw new _Base.SwitchStartEventError(this.startEvent);
    }

    let e;

    try {
      e = await this._waitForEvent("m.key.verification.accept");
    } finally {
      this._waitingForAccept = false;
    }

    let content = e.getContent();
    const sasMethods = intersection(content.short_authentication_string, SAS_SET);

    if (!(KEY_AGREEMENT_SET.has(content.key_agreement_protocol) && HASHES_SET.has(content.hash) && MAC_SET.has(content.message_authentication_code) && sasMethods.length)) {
      throw (0, _Error.newUnknownMethodError)();
    }

    if (typeof content.commitment !== "string") {
      throw (0, _Error.newInvalidMessageError)();
    }

    const keyAgreement = content.key_agreement_protocol;
    const macMethod = content.message_authentication_code;
    const hashCommitment = content.commitment;
    const olmSAS = new global.Olm.SAS();

    try {
      this.ourSASPubKey = olmSAS.get_pubkey();
      await this._send("m.key.verification.key", {
        key: this.ourSASPubKey
      });
      e = await this._waitForEvent("m.key.verification.key"); // FIXME: make sure event is properly formed

      content = e.getContent();

      const commitmentStr = content.key + _anotherJson.default.stringify(startContent); // TODO: use selected hash function (when we support multiple)


      if (olmutil.sha256(commitmentStr) !== hashCommitment) {
        throw newMismatchedCommitmentError();
      }

      this.theirSASPubKey = content.key;
      olmSAS.set_their_key(content.key);
      const sasBytes = calculateKeyAgreement[keyAgreement](this, olmSAS, 6);
      const verifySAS = new Promise((resolve, reject) => {
        this.sasEvent = {
          sas: generateSas(sasBytes, sasMethods),
          confirm: async () => {
            try {
              await this._sendMAC(olmSAS, macMethod);
              resolve();
            } catch (err) {
              reject(err);
            }
          },
          cancel: () => reject((0, _Error.newUserCancelledError)()),
          mismatch: () => reject(newMismatchedSASError())
        };
        this.emit("show_sas", this.sasEvent);
      });
      [e] = await Promise.all([this._waitForEvent("m.key.verification.mac").then(e => {
        // we don't expect any more messages from the other
        // party, and they may send a m.key.verification.done
        // when they're done on their end
        this._expectedEvent = "m.key.verification.done";
        return e;
      }), verifySAS]);
      content = e.getContent();
      await this._checkMAC(olmSAS, content, macMethod);
    } finally {
      olmSAS.free();
    }
  }

  async _doRespondVerification() {
    // as m.related_to is not included in the encrypted content in e2e rooms,
    // we need to make sure it is added
    let content = this._channel.completedContentFromEvent(this.startEvent); // Note: we intersect using our pre-made lists, rather than the sets,
    // so that the result will be in our order of preference.  Then
    // fetching the first element from the array will give our preferred
    // method out of the ones offered by the other party.


    const keyAgreement = intersection(KEY_AGREEMENT_LIST, new Set(content.key_agreement_protocols))[0];
    const hashMethod = intersection(HASHES_LIST, new Set(content.hashes))[0];
    const macMethod = intersection(MAC_LIST, new Set(content.message_authentication_codes))[0]; // FIXME: allow app to specify what SAS methods can be used

    const sasMethods = intersection(content.short_authentication_string, SAS_SET);

    if (!(keyAgreement !== undefined && hashMethod !== undefined && macMethod !== undefined && sasMethods.length)) {
      throw (0, _Error.newUnknownMethodError)();
    }

    const olmSAS = new global.Olm.SAS();

    try {
      const commitmentStr = olmSAS.get_pubkey() + _anotherJson.default.stringify(content);

      await this._send("m.key.verification.accept", {
        key_agreement_protocol: keyAgreement,
        hash: hashMethod,
        message_authentication_code: macMethod,
        short_authentication_string: sasMethods,
        // TODO: use selected hash function (when we support multiple)
        commitment: olmutil.sha256(commitmentStr)
      });
      let e = await this._waitForEvent("m.key.verification.key"); // FIXME: make sure event is properly formed

      content = e.getContent();
      this.theirSASPubKey = content.key;
      olmSAS.set_their_key(content.key);
      this.ourSASPubKey = olmSAS.get_pubkey();
      await this._send("m.key.verification.key", {
        key: this.ourSASPubKey
      });
      const sasBytes = calculateKeyAgreement[keyAgreement](this, olmSAS, 6);
      const verifySAS = new Promise((resolve, reject) => {
        this.sasEvent = {
          sas: generateSas(sasBytes, sasMethods),
          confirm: async () => {
            try {
              await this._sendMAC(olmSAS, macMethod);
              resolve();
            } catch (err) {
              reject(err);
            }
          },
          cancel: () => reject((0, _Error.newUserCancelledError)()),
          mismatch: () => reject(newMismatchedSASError())
        };
        this.emit("show_sas", this.sasEvent);
      });
      [e] = await Promise.all([this._waitForEvent("m.key.verification.mac").then(e => {
        // we don't expect any more messages from the other
        // party, and they may send a m.key.verification.done
        // when they're done on their end
        this._expectedEvent = "m.key.verification.done";
        return e;
      }), verifySAS]);
      content = e.getContent();
      await this._checkMAC(olmSAS, content, macMethod);
    } finally {
      olmSAS.free();
    }
  }

  _sendMAC(olmSAS, method) {
    const mac = {};
    const keyList = [];

    const baseInfo = "MATRIX_KEY_VERIFICATION_MAC" + this._baseApis.getUserId() + this._baseApis.deviceId + this.userId + this.deviceId + this._channel.transactionId;

    const deviceKeyId = `ed25519:${this._baseApis.deviceId}`;
    mac[deviceKeyId] = calculateMAC(olmSAS, method)(this._baseApis.getDeviceEd25519Key(), baseInfo + deviceKeyId);
    keyList.push(deviceKeyId);

    const crossSigningId = this._baseApis.getCrossSigningId();

    if (crossSigningId) {
      const crossSigningKeyId = `ed25519:${crossSigningId}`;
      mac[crossSigningKeyId] = calculateMAC(olmSAS, method)(crossSigningId, baseInfo + crossSigningKeyId);
      keyList.push(crossSigningKeyId);
    }

    const keys = calculateMAC(olmSAS, method)(keyList.sort().join(","), baseInfo + "KEY_IDS");
    return this._send("m.key.verification.mac", {
      mac,
      keys
    });
  }

  async _checkMAC(olmSAS, content, method) {
    const baseInfo = "MATRIX_KEY_VERIFICATION_MAC" + this.userId + this.deviceId + this._baseApis.getUserId() + this._baseApis.deviceId + this._channel.transactionId;

    if (content.keys !== calculateMAC(olmSAS, method)(Object.keys(content.mac).sort().join(","), baseInfo + "KEY_IDS")) {
      throw (0, _Error.newKeyMismatchError)();
    }

    await this._verifyKeys(this.userId, content.mac, (keyId, device, keyInfo) => {
      if (keyInfo !== calculateMAC(olmSAS, method)(device.keys[keyId], baseInfo + keyId)) {
        throw (0, _Error.newKeyMismatchError)();
      }
    });
  }

}

exports.SAS = SAS;