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/*******************************************************************************
uMatrix - a browser extension to black/white list requests.
Copyright (C) 2014-present Raymond Hill
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see {http://www.gnu.org/licenses/}.
Home: https://github.com/gorhill/uMatrix
*/
/* global punycode */
'use strict';
/******************************************************************************/
µMatrix.Matrix = (function() {
/******************************************************************************/
var µm = µMatrix;
var selfieVersion = 1;
/******************************************************************************/
var Matrix = function() {
this.reset();
this.sourceRegister = '';
this.decomposedSourceRegister = [''];
this.specificityRegister = 0;
};
/******************************************************************************/
Matrix.Transparent = 0;
Matrix.Red = 1;
Matrix.Green = 2;
Matrix.Gray = 3;
Matrix.Indirect = 0x00;
Matrix.Direct = 0x80;
Matrix.RedDirect = Matrix.Red | Matrix.Direct;
Matrix.RedIndirect = Matrix.Red | Matrix.Indirect;
Matrix.GreenDirect = Matrix.Green | Matrix.Direct;
Matrix.GreenIndirect = Matrix.Green | Matrix.Indirect;
Matrix.GrayDirect = Matrix.Gray | Matrix.Direct;
Matrix.GrayIndirect = Matrix.Gray | Matrix.Indirect;
/******************************************************************************/
var typeBitOffsets = new Map([
[ '*', 0 ],
[ 'doc', 2 ],
[ 'cookie', 4 ],
[ 'css', 6 ],
[ 'image', 8 ],
[ 'media', 10 ],
[ 'script', 12 ],
[ 'xhr', 14 ],
[ 'frame', 16 ],
[ 'other', 18 ]
]);
var stateToNameMap = new Map([
[ 1, 'block' ],
[ 2, 'allow' ],
[ 3, 'inherit' ]
]);
var nameToStateMap = {
'block': 1,
'allow': 2,
'noop': 2,
'inherit': 3
};
var switchBitOffsets = new Map([
[ 'matrix-off', 0 ],
[ 'https-strict', 2 ],
/* 4 is now unused, formerly assigned to UA spoofing */
[ 'referrer-spoof', 6 ],
[ 'noscript-spoof', 8 ],
[ 'no-workers', 10 ]
]);
var switchStateToNameMap = new Map([
[ 1, 'true' ],
[ 2, 'false' ]
]);
var nameToSwitchStateMap = new Map([
[ 'true', 1 ],
[ 'false', 2 ]
]);
/******************************************************************************/
Matrix.columnHeaderIndices = (function() {
var out = new Map(),
i = 0;
for ( var type of typeBitOffsets.keys() ) {
out.set(type, i++);
}
return out;
})();
Matrix.switchNames = new Set(switchBitOffsets.keys());
/******************************************************************************/
// For performance purpose, as simple tests as possible
var reHostnameVeryCoarse = /[g-z_-]/;
var reIPv4VeryCoarse = /\.\d+$/;
// http://tools.ietf.org/html/rfc5952
// 4.3: "MUST be represented in lowercase"
// Also: http://en.wikipedia.org/wiki/IPv6_address#Literal_IPv6_addresses_in_network_resource_identifiers
var isIPAddress = function(hostname) {
if ( reHostnameVeryCoarse.test(hostname) ) {
return false;
}
if ( reIPv4VeryCoarse.test(hostname) ) {
return true;
}
return hostname.charAt(0) === '[';
};
/******************************************************************************/
var punycodeIf = function(hn) {
return reNotASCII.test(hn) ? punycode.toASCII(hn) : hn;
};
var unpunycodeIf = function(hn) {
return hn.indexOf('xn--') !== -1 ? punycode.toUnicode(hn) : hn;
};
var reNotASCII = /[^\x20-\x7F]/;
/******************************************************************************/
var toBroaderHostname = function(hostname) {
if ( hostname === '*' ) { return ''; }
if ( isIPAddress(hostname) ) {
return toBroaderIPAddress(hostname);
}
var pos = hostname.indexOf('.');
if ( pos === -1 ) {
return '*';
}
return hostname.slice(pos + 1);
};
var toBroaderIPAddress = function(ipaddress) {
// Can't broaden IPv6 (for now)
if ( ipaddress.charAt(0) === '[' ) {
return '*';
}
var pos = ipaddress.lastIndexOf('.');
return pos !== -1 ? ipaddress.slice(0, pos) : '*';
};
Matrix.toBroaderHostname = toBroaderHostname;
/******************************************************************************/
// Find out src-des relationship, using coarse-to-fine grained tests for
// speed. If desHostname is 1st-party to srcHostname, the domain is returned,
// otherwise the empty string.
var extractFirstPartyDesDomain = function(srcHostname, desHostname) {
if ( srcHostname === '*' || desHostname === '*' || desHostname === '1st-party' ) {
return '';
}
var µmuri = µm.URI;
var srcDomain = µmuri.domainFromHostname(srcHostname) || srcHostname;
var desDomain = µmuri.domainFromHostname(desHostname) || desHostname;
return desDomain === srcDomain ? desDomain : '';
};
/******************************************************************************/
Matrix.prototype.reset = function() {
this.switches = new Map();
this.rules = new Map();
this.rootValue = Matrix.RedIndirect;
this.modifiedTime = 0;
if ( this.modifyEventTimer !== undefined ) {
clearTimeout(this.modifyEventTimer);
}
this.modifyEventTimer = undefined;
this.modified();
};
/******************************************************************************/
Matrix.prototype.modified = function() {
this.modifiedTime = Date.now();
if ( this.modifyEventTimer !== undefined ) { return; }
this.modifyEventTimer = vAPI.setTimeout(
( ) => {
this.modifyEventTimer = undefined;
window.dispatchEvent(
new CustomEvent(
'matrixRulesetChange',
{ detail: this }
)
);
},
149
);
};
/******************************************************************************/
Matrix.prototype.decomposeSource = function(srcHostname) {
if ( srcHostname === this.sourceRegister ) { return; }
var hn = srcHostname;
this.decomposedSourceRegister[0] = this.sourceRegister = hn;
var i = 1;
for (;;) {
hn = toBroaderHostname(hn);
this.decomposedSourceRegister[i++] = hn;
if ( hn === '' ) { break; }
}
};
/******************************************************************************/
// Copy another matrix to self. Do this incrementally to minimize impact on
// a live matrix.
Matrix.prototype.assign = function(other) {
var k, entry;
// Remove rules not in other
for ( k of this.rules.keys() ) {
if ( other.rules.has(k) === false ) {
this.rules.delete(k);
}
}
// Remove switches not in other
for ( k of this.switches.keys() ) {
if ( other.switches.has(k) === false ) {
this.switches.delete(k);
}
}
// Add/change rules in other
for ( entry of other.rules ) {
this.rules.set(entry[0], entry[1]);
}
// Add/change switches in other
for ( entry of other.switches ) {
this.switches.set(entry[0], entry[1]);
}
this.modified();
return this;
};
// https://www.youtube.com/watch?v=e9RS4biqyAc
/******************************************************************************/
// If value is undefined, the switch is removed
Matrix.prototype.setSwitch = function(switchName, srcHostname, newVal) {
var bitOffset = switchBitOffsets.get(switchName);
if ( bitOffset === undefined ) {
return false;
}
if ( newVal === this.evaluateSwitch(switchName, srcHostname) ) {
return false;
}
var bits = this.switches.get(srcHostname) || 0;
bits &= ~(3 << bitOffset);
bits |= newVal << bitOffset;
if ( bits === 0 ) {
this.switches.delete(srcHostname);
} else {
this.switches.set(srcHostname, bits);
}
this.modified();
return true;
};
/******************************************************************************/
Matrix.prototype.setCell = function(srcHostname, desHostname, type, state) {
var bitOffset = typeBitOffsets.get(type),
k = srcHostname + ' ' + desHostname,
oldBitmap = this.rules.get(k);
if ( oldBitmap === undefined ) {
oldBitmap = 0;
}
var newBitmap = oldBitmap & ~(3 << bitOffset) | (state << bitOffset);
if ( newBitmap === oldBitmap ) {
return false;
}
if ( newBitmap === 0 ) {
this.rules.delete(k);
} else {
this.rules.set(k, newBitmap);
}
this.modified();
return true;
};
/******************************************************************************/
Matrix.prototype.blacklistCell = function(srcHostname, desHostname, type) {
var r = this.evaluateCellZ(srcHostname, desHostname, type);
if ( r === 1 ) {
return false;
}
this.setCell(srcHostname, desHostname, type, 0);
r = this.evaluateCellZ(srcHostname, desHostname, type);
if ( r === 1 ) {
return true;
}
this.setCell(srcHostname, desHostname, type, 1);
return true;
};
/******************************************************************************/
Matrix.prototype.whitelistCell = function(srcHostname, desHostname, type) {
var r = this.evaluateCellZ(srcHostname, desHostname, type);
if ( r === 2 ) {
return false;
}
this.setCell(srcHostname, desHostname, type, 0);
r = this.evaluateCellZ(srcHostname, desHostname, type);
if ( r === 2 ) {
return true;
}
this.setCell(srcHostname, desHostname, type, 2);
return true;
};
/******************************************************************************/
Matrix.prototype.graylistCell = function(srcHostname, desHostname, type) {
var r = this.evaluateCellZ(srcHostname, desHostname, type);
if ( r === 0 || r === 3 ) {
return false;
}
this.setCell(srcHostname, desHostname, type, 0);
r = this.evaluateCellZ(srcHostname, desHostname, type);
if ( r === 0 || r === 3 ) {
return true;
}
this.setCell(srcHostname, desHostname, type, 3);
return true;
};
/******************************************************************************/
Matrix.prototype.evaluateCell = function(srcHostname, desHostname, type) {
var key = srcHostname + ' ' + desHostname;
var bitmap = this.rules.get(key);
if ( bitmap === undefined ) {
return 0;
}
return bitmap >> typeBitOffsets.get(type) & 3;
};
/******************************************************************************/
Matrix.prototype.evaluateCellZ = function(srcHostname, desHostname, type) {
this.decomposeSource(srcHostname);
var bitOffset = typeBitOffsets.get(type),
s, v, i = 0;
for (;;) {
s = this.decomposedSourceRegister[i++];
if ( s === '' ) { break; }
v = this.rules.get(s + ' ' + desHostname);
if ( v !== undefined ) {
v = v >> bitOffset & 3;
if ( v !== 0 ) {
return v;
}
}
}
// srcHostname is '*' at this point
// Preset blacklisted hostnames are blacklisted in global scope
if ( type === '*' && µm.ubiquitousBlacklist.test(desHostname) ) {
return 1;
}
// https://github.com/gorhill/uMatrix/issues/65
// Hardcoded global `doc` rule
if ( type === 'doc' && desHostname === '*' ) {
return 2;
}
return 0;
};
/******************************************************************************/
Matrix.prototype.evaluateCellZXY = function(srcHostname, desHostname, type) {
// Matrix filtering switch
this.specificityRegister = 0;
if ( this.evaluateSwitchZ('matrix-off', srcHostname) ) {
return Matrix.GreenIndirect;
}
// TODO: There are cells evaluated twice when the type is '*'. Unsure
// whether it's worth trying to avoid that, as this could introduce
// overhead which may not be gained back by skipping the redundant tests.
// And this happens *only* when building the matrix UI, not when
// evaluating net requests.
// Specific-hostname specific-type cell
this.specificityRegister = 1;
var r = this.evaluateCellZ(srcHostname, desHostname, type);
if ( r === 1 ) { return Matrix.RedDirect; }
if ( r === 2 ) { return Matrix.GreenDirect; }
// Specific-hostname any-type cell
this.specificityRegister = 2;
var rl = this.evaluateCellZ(srcHostname, desHostname, '*');
if ( rl === 1 ) { return Matrix.RedIndirect; }
var d = desHostname;
var firstPartyDesDomain = extractFirstPartyDesDomain(srcHostname, desHostname);
// Ancestor cells, up to 1st-party destination domain
if ( firstPartyDesDomain !== '' ) {
this.specificityRegister = 3;
for (;;) {
if ( d === firstPartyDesDomain ) { break; }
d = d.slice(d.indexOf('.') + 1);
// specific-hostname specific-type cell
r = this.evaluateCellZ(srcHostname, d, type);
if ( r === 1 ) { return Matrix.RedIndirect; }
if ( r === 2 ) { return Matrix.GreenIndirect; }
// Do not override a narrower rule
if ( rl !== 2 ) {
rl = this.evaluateCellZ(srcHostname, d, '*');
if ( rl === 1 ) { return Matrix.RedIndirect; }
}
}
// 1st-party specific-type cell: it's a special row, looked up only
// when destination is 1st-party to source.
r = this.evaluateCellZ(srcHostname, '1st-party', type);
if ( r === 1 ) { return Matrix.RedIndirect; }
if ( r === 2 ) { return Matrix.GreenIndirect; }
// Do not override narrower rule
if ( rl !== 2 ) {
rl = this.evaluateCellZ(srcHostname, '1st-party', '*');
if ( rl === 1 ) { return Matrix.RedIndirect; }
}
}
// Keep going, up to root
this.specificityRegister = 4;
for (;;) {
d = toBroaderHostname(d);
if ( d === '*' ) { break; }
// specific-hostname specific-type cell
r = this.evaluateCellZ(srcHostname, d, type);
if ( r === 1 ) { return Matrix.RedIndirect; }
if ( r === 2 ) { return Matrix.GreenIndirect; }
// Do not override narrower rule
if ( rl !== 2 ) {
rl = this.evaluateCellZ(srcHostname, d, '*');
if ( rl === 1 ) { return Matrix.RedIndirect; }
}
}
// Any-hostname specific-type cells
this.specificityRegister = 5;
r = this.evaluateCellZ(srcHostname, '*', type);
// Line below is strict-blocking
if ( r === 1 ) { return Matrix.RedIndirect; }
// Narrower rule wins
if ( rl === 2 ) { return Matrix.GreenIndirect; }
if ( r === 2 ) { return Matrix.GreenIndirect; }
// Any-hostname any-type cell
this.specificityRegister = 6;
r = this.evaluateCellZ(srcHostname, '*', '*');
if ( r === 1 ) { return Matrix.RedIndirect; }
if ( r === 2 ) { return Matrix.GreenIndirect; }
return this.rootValue;
};
// https://www.youtube.com/watch?v=4C5ZkwrnVfM
/******************************************************************************/
Matrix.prototype.evaluateRowZXY = function(srcHostname, desHostname) {
let out = [];
for ( let type of typeBitOffsets.keys() ) {
out.push(this.evaluateCellZXY(srcHostname, desHostname, type));
}
return out;
};
/******************************************************************************/
Matrix.prototype.mustBlock = function(srcHostname, desHostname, type) {
return (this.evaluateCellZXY(srcHostname, desHostname, type) & 3) === Matrix.Red;
};
/******************************************************************************/
Matrix.prototype.srcHostnameFromRule = function(rule) {
return rule.slice(0, rule.indexOf(' '));
};
/******************************************************************************/
Matrix.prototype.desHostnameFromRule = function(rule) {
return rule.slice(rule.indexOf(' ') + 1);
};
/******************************************************************************/
Matrix.prototype.setSwitchZ = function(switchName, srcHostname, newState) {
var bitOffset = switchBitOffsets.get(switchName);
if ( bitOffset === undefined ) {
return false;
}
var state = this.evaluateSwitchZ(switchName, srcHostname);
if ( newState === state ) {
return false;
}
if ( newState === undefined ) {
newState = !state;
}
var bits = this.switches.get(srcHostname) || 0;
bits &= ~(3 << bitOffset);
if ( bits === 0 ) {
this.switches.delete(srcHostname);
} else {
this.switches.set(srcHostname, bits);
}
this.modified();
state = this.evaluateSwitchZ(switchName, srcHostname);
if ( state === newState ) {
return true;
}
this.switches.set(srcHostname, bits | ((newState ? 1 : 2) << bitOffset));
return true;
};
/******************************************************************************/
// 0 = inherit from broader scope, up to default state
// 1 = non-default state
// 2 = forced default state (to override a broader non-default state)
Matrix.prototype.evaluateSwitch = function(switchName, srcHostname) {
var bits = this.switches.get(srcHostname) || 0;
if ( bits === 0 ) {
return 0;
}
var bitOffset = switchBitOffsets.get(switchName);
if ( bitOffset === undefined ) {
return 0;
}
return (bits >> bitOffset) & 3;
};
/******************************************************************************/
Matrix.prototype.evaluateSwitchZ = function(switchName, srcHostname) {
var bitOffset = switchBitOffsets.get(switchName);
if ( bitOffset === undefined ) { return false; }
this.decomposeSource(srcHostname);
var s, bits, i = 0;
for (;;) {
s = this.decomposedSourceRegister[i++];
if ( s === '' ) { break; }
bits = this.switches.get(s) || 0;
if ( bits !== 0 ) {
bits = bits >> bitOffset & 3;
if ( bits !== 0 ) {
return bits === 1;
}
}
}
return false;
};
/******************************************************************************/
Matrix.prototype.extractAllSourceHostnames = (function() {
var cachedResult = new Set();
var matrixId = 0;
var readTime = 0;
return function() {
if ( matrixId !== this.id || readTime !== this.modifiedTime ) {
cachedResult.clear();
for ( var rule of this.rules.keys() ) {
cachedResult.add(rule.slice(0, rule.indexOf(' ')));
}
matrixId = this.id;
readTime = this.modifiedTime;
}
return cachedResult;
};
})();
/******************************************************************************/
// https://github.com/gorhill/uMatrix/issues/759
// Backward compatibility: 'plugin' => 'media'
Matrix.prototype.partsFromLine = function(line) {
let fields = line.split(/\s+/);
if ( fields.length < 3 ) { return; }
// Switches
if ( this.reSwitchRule.test(fields[0]) ) {
fields[0] = fields[0].slice(0, -1);
if ( switchBitOffsets.has(fields[0]) === false ) { return; }
fields[1] = punycodeIf(fields[1]);
fields[2] = nameToSwitchStateMap.get(fields[2]);
if ( fields[2] === undefined ) { return; }
fields.length = 3;
return fields;
}
// Rules
if ( fields.length < 4 ) { return; }
fields[0] = punycodeIf(fields[0]);
fields[1] = punycodeIf(fields[1]);
if ( fields[2] === 'plugin' ) { fields[2] = 'media'; }
if ( typeBitOffsets.get(fields[2]) === undefined ) { return; }
if ( nameToStateMap.hasOwnProperty(fields[3]) === false ) { return; }
fields[3] = nameToStateMap[fields[3]];
fields.length = 4;
return fields;
};
Matrix.prototype.reSwitchRule = /^[0-9a-z-]+:$/;
/******************************************************************************/
Matrix.prototype.fromArray = function(lines, append) {
let matrix = append === true ? this : new Matrix();
for ( let line of lines ) {
matrix.addFromLine(line);
}
if ( append !== true ) {
this.assign(matrix);
}
this.modified();
};
Matrix.prototype.toArray = function() {
let out = [];
for ( let rule of this.rules.keys() ) {
let srcHostname = this.srcHostnameFromRule(rule);
let desHostname = this.desHostnameFromRule(rule);
for ( let type of typeBitOffsets.keys() ) {
let val = this.evaluateCell(srcHostname, desHostname, type);
if ( val === 0 ) { continue; }
out.push(
unpunycodeIf(srcHostname) + ' ' +
unpunycodeIf(desHostname) + ' ' +
type + ' ' +
stateToNameMap.get(val)
);
}
}
for ( let srcHostname of this.switches.keys() ) {
for ( let switchName of switchBitOffsets.keys() ) {
let val = this.evaluateSwitch(switchName, srcHostname);
if ( val === 0 ) { continue; }
out.push(
switchName + ': ' +
srcHostname + ' ' +
switchStateToNameMap.get(val)
);
}
}
return out;
};
/******************************************************************************/
Matrix.prototype.fromString = function(text, append) {
let matrix = append === true ? this : new Matrix();
let textEnd = text.length;
let lineBeg = 0;
while ( lineBeg < textEnd ) {
let lineEnd = text.indexOf('\n', lineBeg);
if ( lineEnd === -1 ) {
lineEnd = text.indexOf('\r', lineBeg);
if ( lineEnd === -1 ) {
lineEnd = textEnd;
}
}
let line = text.slice(lineBeg, lineEnd).trim();
lineBeg = lineEnd + 1;
let pos = line.indexOf('# ');
if ( pos !== -1 ) {
line = line.slice(0, pos).trim();
}
if ( line === '' ) { continue; }
matrix.addFromLine(line);
}
if ( append !== true ) {
this.assign(matrix);
}
this.modified();
};
Matrix.prototype.toString = function() {
return this.toArray().join('\n');
};
/******************************************************************************/
Matrix.prototype.addFromLine = function(line) {
let fields = this.partsFromLine(line);
if ( fields !== undefined ) {
// Switches
if ( fields.length === 3 ) {
return this.setSwitch(fields[0], fields[1], fields[2]);
}
// Rules
if ( fields.length === 4 ) {
return this.setCell(fields[0], fields[1], fields[2], fields[3]);
}
}
};
Matrix.prototype.removeFromLine = function(line) {
let fields = this.partsFromLine(line);
if ( fields !== undefined ) {
// Switches
if ( fields.length === 3 ) {
return this.setSwitch(fields[0], fields[1], 0);
}
// Rules
if ( fields.length === 4 ) {
return this.setCell(fields[0], fields[1], fields[2], 0);
}
}
};
/******************************************************************************/
Matrix.prototype.fromSelfie = function(selfie) {
if ( selfie.version !== selfieVersion ) { return false; }
this.switches = new Map(selfie.switches);
this.rules = new Map(selfie.rules);
this.modified();
return true;
};
Matrix.prototype.toSelfie = function() {
return {
version: selfieVersion,
switches: Array.from(this.switches),
rules: Array.from(this.rules)
};
};
/******************************************************************************/
Matrix.prototype.diff = function(other, srcHostname, desHostnames) {
var out = [];
var desHostname, type;
var switchName, i, thisVal, otherVal;
for (;;) {
for ( switchName of switchBitOffsets.keys() ) {
thisVal = this.evaluateSwitch(switchName, srcHostname);
otherVal = other.evaluateSwitch(switchName, srcHostname);
if ( thisVal !== otherVal ) {
out.push({
'what': switchName,
'src': srcHostname
});
}
}
i = desHostnames.length;
while ( i-- ) {
desHostname = desHostnames[i];
for ( type of typeBitOffsets.keys() ) {
thisVal = this.evaluateCell(srcHostname, desHostname, type);
otherVal = other.evaluateCell(srcHostname, desHostname, type);
if ( thisVal === otherVal ) { continue; }
out.push({
'what': 'rule',
'src': srcHostname,
'des': desHostname,
'type': type
});
}
}
srcHostname = toBroaderHostname(srcHostname);
if ( srcHostname === '' ) { break; }
}
return out;
};
/******************************************************************************/
Matrix.prototype.applyDiff = function(diff, from) {
var changed = false;
var i = diff.length;
var action, val;
while ( i-- ) {
action = diff[i];
if ( action.what === 'rule' ) {
val = from.evaluateCell(action.src, action.des, action.type);
changed = this.setCell(action.src, action.des, action.type, val) || changed;
continue;
}
if ( switchBitOffsets.has(action.what) ) {
val = from.evaluateSwitch(action.what, action.src);
changed = this.setSwitch(action.what, action.src, val) || changed;
continue;
}
}
return changed;
};
Matrix.prototype.copyRuleset = function(entries, from, deep) {
let changed = false;
for ( let entry of entries ) {
let srcHn = entry.srcHn;
for (;;) {
if (
entry.switchName !== undefined &&
switchBitOffsets.has(entry.switchName)
) {
let val = from.evaluateSwitch(entry.switchName, srcHn);
if ( this.setSwitch(entry.switchName, srcHn, val) ) {
changed = true;
}
} else if ( entry.desHn && entry.type ) {
let val = from.evaluateCell(srcHn, entry.desHn, entry.type);
if ( this.setCell(srcHn, entry.desHn, entry.type, val) ) {
changed = true;
}
}
if ( !deep ) { break; }
srcHn = toBroaderHostname(srcHn);
if ( srcHn === '' ) { break; }
}
}
return changed;
};
/******************************************************************************/
return Matrix;
/******************************************************************************/
// https://www.youtube.com/watch?v=wlNrQGmj6oQ
})();
/******************************************************************************/