source: trip-planner-front/node_modules/sshpk/lib/fingerprint.js

// Copyright 2018 Joyent, Inc.

module.exports = Fingerprint;

var assert = require('assert-plus');
var Buffer = require('safer-buffer').Buffer;
var algs = require('./algs');
var crypto = require('crypto');
var errs = require('./errors');
var Key = require('./key');
var PrivateKey = require('./private-key');
var Certificate = require('./certificate');
var utils = require('./utils');

var FingerprintFormatError = errs.FingerprintFormatError;
var InvalidAlgorithmError = errs.InvalidAlgorithmError;

function Fingerprint(opts) {
        assert.object(opts, 'options');
        assert.string(opts.type, 'options.type');
        assert.buffer(opts.hash, 'options.hash');
        assert.string(opts.algorithm, 'options.algorithm');

        this.algorithm = opts.algorithm.toLowerCase();
        if (algs.hashAlgs[this.algorithm] !== true)
                throw (new InvalidAlgorithmError(this.algorithm));

        this.hash = opts.hash;
        this.type = opts.type;
        this.hashType = opts.hashType;
}

Fingerprint.prototype.toString = function (format) {
        if (format === undefined) {
                if (this.algorithm === 'md5' || this.hashType === 'spki')
                        format = 'hex';
                else
                        format = 'base64';
        }
        assert.string(format);

        switch (format) {
        case 'hex':
                if (this.hashType === 'spki')
                        return (this.hash.toString('hex'));
                return (addColons(this.hash.toString('hex')));
        case 'base64':
                if (this.hashType === 'spki')
                        return (this.hash.toString('base64'));
                return (sshBase64Format(this.algorithm,
                    this.hash.toString('base64')));
        default:
                throw (new FingerprintFormatError(undefined, format));
        }
};

Fingerprint.prototype.matches = function (other) {
        assert.object(other, 'key or certificate');
        if (this.type === 'key' && this.hashType !== 'ssh') {
                utils.assertCompatible(other, Key, [1, 7], 'key with spki');
                if (PrivateKey.isPrivateKey(other)) {
                        utils.assertCompatible(other, PrivateKey, [1, 6],
                            'privatekey with spki support');
                }
        } else if (this.type === 'key') {
                utils.assertCompatible(other, Key, [1, 0], 'key');
        } else {
                utils.assertCompatible(other, Certificate, [1, 0],
                    'certificate');
        }

        var theirHash = other.hash(this.algorithm, this.hashType);
        var theirHash2 = crypto.createHash(this.algorithm).
            update(theirHash).digest('base64');

        if (this.hash2 === undefined)
                this.hash2 = crypto.createHash(this.algorithm).
                    update(this.hash).digest('base64');

        return (this.hash2 === theirHash2);
};

/*JSSTYLED*/
var base64RE = /^[A-Za-z0-9+\/=]+$/;
/*JSSTYLED*/
var hexRE = /^[a-fA-F0-9]+$/;

Fingerprint.parse = function (fp, options) {
        assert.string(fp, 'fingerprint');

        var alg, hash, enAlgs;
        if (Array.isArray(options)) {
                enAlgs = options;
                options = {};
        }
        assert.optionalObject(options, 'options');
        if (options === undefined)
                options = {};
        if (options.enAlgs !== undefined)
                enAlgs = options.enAlgs;
        if (options.algorithms !== undefined)
                enAlgs = options.algorithms;
        assert.optionalArrayOfString(enAlgs, 'algorithms');

        var hashType = 'ssh';
        if (options.hashType !== undefined)
                hashType = options.hashType;
        assert.string(hashType, 'options.hashType');

        var parts = fp.split(':');
        if (parts.length == 2) {
                alg = parts[0].toLowerCase();
                if (!base64RE.test(parts[1]))
                        throw (new FingerprintFormatError(fp));
                try {
                        hash = Buffer.from(parts[1], 'base64');
                } catch (e) {
                        throw (new FingerprintFormatError(fp));
                }
        } else if (parts.length > 2) {
                alg = 'md5';
                if (parts[0].toLowerCase() === 'md5')
                        parts = parts.slice(1);
                parts = parts.map(function (p) {
                        while (p.length < 2)
                                p = '0' + p;
                        if (p.length > 2)
                                throw (new FingerprintFormatError(fp));
                        return (p);
                });
                parts = parts.join('');
                if (!hexRE.test(parts) || parts.length % 2 !== 0)
                        throw (new FingerprintFormatError(fp));
                try {
                        hash = Buffer.from(parts, 'hex');
                } catch (e) {
                        throw (new FingerprintFormatError(fp));
                }
        } else {
                if (hexRE.test(fp)) {
                        hash = Buffer.from(fp, 'hex');
                } else if (base64RE.test(fp)) {
                        hash = Buffer.from(fp, 'base64');
                } else {
                        throw (new FingerprintFormatError(fp));
                }

                switch (hash.length) {
                case 32:
                        alg = 'sha256';
                        break;
                case 16:
                        alg = 'md5';
                        break;
                case 20:
                        alg = 'sha1';
                        break;
                case 64:
                        alg = 'sha512';
                        break;
                default:
                        throw (new FingerprintFormatError(fp));
                }

                /* Plain hex/base64: guess it's probably SPKI unless told. */
                if (options.hashType === undefined)
                        hashType = 'spki';
        }

        if (alg === undefined)
                throw (new FingerprintFormatError(fp));

        if (algs.hashAlgs[alg] === undefined)
                throw (new InvalidAlgorithmError(alg));

        if (enAlgs !== undefined) {
                enAlgs = enAlgs.map(function (a) { return a.toLowerCase(); });
                if (enAlgs.indexOf(alg) === -1)
                        throw (new InvalidAlgorithmError(alg));
        }

        return (new Fingerprint({
                algorithm: alg,
                hash: hash,
                type: options.type || 'key',
                hashType: hashType
        }));
};

function addColons(s) {
        /*JSSTYLED*/
        return (s.replace(/(.{2})(?=.)/g, '$1:'));
}

function base64Strip(s) {
        /*JSSTYLED*/
        return (s.replace(/=*$/, ''));
}

function sshBase64Format(alg, h) {
        return (alg.toUpperCase() + ':' + base64Strip(h));
}

Fingerprint.isFingerprint = function (obj, ver) {
        return (utils.isCompatible(obj, Fingerprint, ver));
};

/*
 * API versions for Fingerprint:
 * [1,0] -- initial ver
 * [1,1] -- first tagged ver
 * [1,2] -- hashType and spki support
 */
Fingerprint.prototype._sshpkApiVersion = [1, 2];

Fingerprint._oldVersionDetect = function (obj) {
        assert.func(obj.toString);
        assert.func(obj.matches);
        return ([1, 0]);
};