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Added protection for getParameter (webGL)

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Fixes #329
This commit is contained in:
kkapsner 2019-09-19 00:47:52 +02:00
parent 64d4aa3f73
commit aa7a4e1d06
7 changed files with 276 additions and 1 deletions
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157
lib/modifiedCanvasAPI.js
View file

@ -511,6 +511,163 @@
});
};
}
},
getParameter: {
type: "readout",
getStatus: function(obj, status, prefs){
const protectedPartChecker = getProtectedPartChecker(prefs, status.url);
status = Object.create(status);
status.active = protectedPartChecker(["readout", "input"]);
return status;
},
object: ["WebGLRenderingContext", "WebGL2RenderingContext"],
fakeGenerator: function(checker){
function getNumber(originalValue, max, index, window){
const bitLength = Math.floor(Math.log2(max) + 1);
const rng = randomSupply.getBitRng(bitLength, window);
let value = 0;
for (let i = 0; i < bitLength; i += 1){
value <<= 1;
value ^= rng(originalValue, index + i);
}
return value;
}
const types = {
decimal: function(originalValue, definition, window){
const int = Math.floor(originalValue);
if (int !== originalValue){
const decimal = originalValue - int;
const rng = randomSupply.getRng(1, window);
const newDecimal = decimal * (rng(definition.pname) / 0xFFFFFFFF);
return int + newDecimal;
}
else {
return originalValue;
}
},
shift: function(originalValue, definition, window){
const value = getNumber(originalValue, definition.max, definition.pname, window);
return originalValue >>> value;
},
"-": function(originalValue, definition, window){
const value = getNumber(originalValue, definition.max, definition.pname, window) *
(definition.factor || 1);
if (value > originalValue){
return 0;
}
return originalValue - value;
}
};
const changeDefinition = {
2928: {name: "DEPTH_RANGE", type: "decimal", isArray: true},
3379: {name: "MAX_TEXTURE_SIZE", type: "shift", max: 1},
3386: {name: "MAX_VIEWPORT_DIMS", type: "shift", max: 1, isArray: true},
32883: {name: "MAX_3D_TEXTURE_SIZE", type: "shift", max: 1},
33000: {name: "MAX_ELEMENTS_VERTICES", type: "-", max: 3, factor: 50},
33001: {name: "MAX_ELEMENTS_INDICES", type: "-", max: 3, factor: 50},
33901: {name: "ALIASED_POINT_SIZE_RANGE", type: "decimal", isArray: true},
33902: {name: "ALIASED_LINE_WIDTH_RANGE", type: "decimal", isArray: true},
34024: {name: "MAX_RENDERBUFFER_SIZE", type: "shift", max: 1},
34045: {name: "MAX_TEXTURE_LOD_BIAS", type: "-", max: 1, factor: 1},
34076: {name: "MAX_CUBE_MAP_TEXTURE_SIZE", type: "shift", max: 1},
34921: {name: "MAX_VERTEX_ATTRIBS", type: "shift", max: 1},
34930: {name: "MAX_TEXTURE_IMAGE_UNITS", type: "shift", max: 1},
35071: {name: "MAX_ARRAY_TEXTURE_LAYERS", type: "shift", max: 1},
35371: {name: "MAX_VERTEX_UNIFORM_BLOCKS", type: "-", max: 1, factor: 1},
35373: {name: "MAX_FRAGMENT_UNIFORM_BLOCKS", type: "-", max: 1, factor: 1},
35374: {name: "MAX_COMBINED_UNIFORM_BLOCKS", type: "-", max: 3, factor: 1},
35375: {name: "MAX_UNIFORM_BUFFER_BINDINGS", type: "-", max: 3, factor: 1},
35376: {name: "MAX_UNIFORM_BLOCK_SIZE", type: "shift", max: 1},
35377: {name: "MAX_COMBINED_VERTEX_UNIFORM_COMPONENTS", type: "-", max: 7, factor: 10},
35379: {name: "MAX_COMBINED_FRAGMENT_UNIFORM_COMPONENTS", type: "-", max: 7, factor: 10},
35657: {name: "MAX_FRAGMENT_UNIFORM_COMPONENTS", type: "shift", max: 1},
35658: {name: "MAX_VERTEX_UNIFORM_COMPONENTS", type: "shift", max: 1},
35659: {name: "MAX_VARYING_COMPONENTS", type: "shift", max: 1},
35660: {name: "MAX_VERTEX_TEXTURE_IMAGE_UNITS", type: "shift", max: 1},
35661: {name: "MAX_COMBINED_TEXTURE_IMAGE_UNITS", type: "-", max: 1, factor: 2},
35968: {name: "MAX_TRANSFORM_FEEDBACK_SEPARATE_COMPONENTS", type: "shift", max: 1},
35978: {name: "MAX_TRANSFORM_FEEDBACK_INTERLEAVED_COMPONENTS", type: "shift", max: 1},
36203: {name: "MAX_ELEMENT_INDEX", type: "-", max: 15, factor: 1},
36347: {name: "MAX_VERTEX_UNIFORM_VECTORS", type: "shift", max: 1},
36348: {name: "MAX_VARYING_VECTORS", type: "shift", max: 1},
36349: {name: "MAX_FRAGMENT_UNIFORM_VECTORS", type: "shift", max: 1},
37154: {name: "MAX_VERTEX_OUTPUT_COMPONENTS", type: "shift", max: 1},
37157: {name: "MAX_FRAGMENT_INPUT_COMPONENTS", type: "shift", max: 1},
7936: {name: "VENDOR", fake: function(originalValue, window, prefs){
const settingValue = prefs("webGLVendor") || originalValue;
return {value: settingValue, faked: settingValue === originalValue};
}},
7937: {name: "RENDERER", fake: function(originalValue, window, prefs){
const settingValue = prefs("webGLRenderer") || originalValue;
return {value: settingValue, faked: settingValue === originalValue};
}},
37445: {name: "UNMASKED_VENDOR_WEBGL", fake: function(originalValue, window, prefs){
const settingValue = prefs("webGLUnmaskedVendor") || originalValue;
return {value: settingValue, faked: settingValue === originalValue};
}},
37446: {name: "UNMASKED_RENDERER_WEBGL", fake: function(originalValue, window, prefs){
const settingValue = prefs("webGLUnmaskedRenderer") || originalValue;
return {value: settingValue, faked: settingValue === originalValue};
}}
};
const parameterNames = Object.keys(changeDefinition);
parameterNames.forEach(function(parameterName){
const definition = changeDefinition[parameterName];
definition.pname = parameterName;
if (!definition.fake){
definition.fake = definition.isArray?
function fake(originalValue, window){
let faked = false;
let fakedValue = [];
for (var i = 0; i < originalValue.length; i += 1){
fakedValue[i] = types[this.type](originalValue[i], this, window);
faked |= originalValue[i] === fakedValue[i];
originalValue[i] = fakedValue[i];
}
this.fake = function(originalValue){
if (faked){
for (var i = 0; i < originalValue.length; i += 1){
originalValue[i] = fakedValue[i];
}
}
return {
value: originalValue,
faked
};
};
return {
value: originalValue,
faked
};
}:
function fake(originalValue, window){
let value = types[this.type](originalValue, this, window);
let faked = value === originalValue;
this.fake = function(){
return {value, faked};
};
return {value, faked};
};
}
});
return function getParameter(pname){
return checkerWrapper(checker, this, arguments, function(args, check){
var {prefs, notify, window, original} = check;
const originalValue = original.apply(this, window.Array.from(args));
if (changeDefinition[pname]){
const definition = changeDefinition[pname];
const {value, faked} = definition.fake(originalValue, window, prefs);
if (faked){
notify("fakedReadout");
}
return value;
}
else {
return originalValue;
}
});
};
}
}
};
Object.keys(scope.changedFunctions).forEach(function(key){

18
lib/settingDefinitions.js
View file

@ -98,7 +98,7 @@
{message: "input", level: 2},
"fillText", "strokeText",
{name: "webGL", level: 2},
"readPixels",
"readPixels", "getParameter",
{name: "Audio-API", level: 1},
"getFloatFrequencyData", "getByteFrequencyData", "getFloatTimeDomainData", "getByteTimeDomainData",
"getChannelData", "copyFromChannel",
@ -148,6 +148,22 @@
name: "fakeAlphaChannel",
defaultValue: false
},
{
name: "webGLVendor",
defaultValue: ""
},
{
name: "webGLRenderer",
defaultValue: ""
},
{
name: "webGLUnmaskedVendor",
defaultValue: ""
},
{
name: "webGLUnmaskedRenderer",
defaultValue: ""
},
{
name: "persistentRndStorage",
defaultValue: ""