/**
* Tools for SVG sanitization
* @module sanitize
* @license MIT
*
* @copyright 2010 Alexis Deveria, 2010 Jeff Schiller
*/
import {getReverseNS, NS} from './namespaces.js';
import {isGecko} from './browser.js';
import {getHref, setHref, getUrlFromAttr} from './utilities.js';
const REVERSE_NS = getReverseNS();
// Todo: Split out into core attributes, presentation attributes, etc. so consistent
/**
* This defines which elements and attributes that we support (or at least
* don't remove)
* @type {PlainObject}
*/
const svgWhiteList_ = {
// SVG Elements
a: ['class', 'clip-path', 'clip-rule', 'fill', 'fill-opacity', 'fill-rule', 'filter', 'id', 'mask', 'opacity', 'stroke', 'stroke-dasharray', 'stroke-dashoffset', 'stroke-linecap', 'stroke-linejoin', 'stroke-miterlimit', 'stroke-opacity', 'stroke-width', 'style', 'systemLanguage', 'transform', 'xlink:href', 'xlink:title'],
circle: ['class', 'clip-path', 'clip-rule', 'cx', 'cy', 'fill', 'fill-opacity', 'fill-rule', 'filter', 'id', 'mask', 'opacity', 'r', 'requiredFeatures', 'stroke', 'stroke-dasharray', 'stroke-dashoffset', 'stroke-linecap', 'stroke-linejoin', 'stroke-miterlimit', 'stroke-opacity', 'stroke-width', 'style', 'systemLanguage', 'transform'],
clipPath: ['class', 'clipPathUnits', 'id'],
defs: [],
style: ['type'],
desc: [],
ellipse: ['class', 'clip-path', 'clip-rule', 'cx', 'cy', 'fill', 'fill-opacity', 'fill-rule', 'filter', 'id', 'mask', 'opacity', 'requiredFeatures', 'rx', 'ry', 'stroke', 'stroke-dasharray', 'stroke-dashoffset', 'stroke-linecap', 'stroke-linejoin', 'stroke-miterlimit', 'stroke-opacity', 'stroke-width', 'style', 'systemLanguage', 'transform'],
feGaussianBlur: ['class', 'color-interpolation-filters', 'id', 'requiredFeatures', 'stdDeviation'],
feMorphology: ['class', 'in', 'operator', 'radius'],
filter: ['class', 'color-interpolation-filters', 'filterRes', 'filterUnits', 'height', 'id', 'primitiveUnits', 'requiredFeatures', 'width', 'x', 'xlink:href', 'y'],
foreignObject: ['class', 'font-size', 'height', 'id', 'opacity', 'requiredFeatures', 'style', 'transform', 'width', 'x', 'y'],
g: ['class', 'clip-path', 'clip-rule', 'id', 'display', 'fill', 'fill-opacity', 'fill-rule', 'filter', 'mask', 'opacity', 'requiredFeatures', 'stroke', 'stroke-dasharray', 'stroke-dashoffset', 'stroke-linecap', 'stroke-linejoin', 'stroke-miterlimit', 'stroke-opacity', 'stroke-width', 'style', 'systemLanguage', 'transform', 'font-family', 'font-size', 'font-style', 'font-weight', 'text-anchor'],
image: ['class', 'clip-path', 'clip-rule', 'filter', 'height', 'id', 'mask', 'opacity', 'requiredFeatures', 'style', 'systemLanguage', 'transform', 'width', 'x', 'xlink:href', 'xlink:title', 'y'],
line: ['class', 'clip-path', 'clip-rule', 'fill', 'fill-opacity', 'fill-rule', 'filter', 'id', 'marker-end', 'marker-mid', 'marker-start', 'mask', 'opacity', 'requiredFeatures', 'stroke', 'stroke-dasharray', 'stroke-dashoffset', 'stroke-linecap', 'stroke-linejoin', 'stroke-miterlimit', 'stroke-opacity', 'stroke-width', 'style', 'systemLanguage', 'transform', 'x1', 'x2', 'y1', 'y2'],
linearGradient: ['class', 'id', 'gradientTransform', 'gradientUnits', 'requiredFeatures', 'spreadMethod', 'systemLanguage', 'x1', 'x2', 'xlink:href', 'y1', 'y2'],
marker: ['id', 'class', 'markerHeight', 'markerUnits', 'markerWidth', 'orient', 'preserveAspectRatio', 'refX', 'refY', 'systemLanguage', 'viewBox'],
mask: ['class', 'height', 'id', 'maskContentUnits', 'maskUnits', 'width', 'x', 'y'],
metadata: ['class', 'id'],
path: ['class', 'clip-path', 'clip-rule', 'd', 'fill', 'fill-opacity', 'fill-rule', 'filter', 'id', 'marker-end', 'marker-mid', 'marker-start', 'mask', 'opacity', 'requiredFeatures', 'stroke', 'stroke-dasharray', 'stroke-dashoffset', 'stroke-linecap', 'stroke-linejoin', 'stroke-miterlimit', 'stroke-opacity', 'stroke-width', 'style', 'systemLanguage', 'transform'],
pattern: ['class', 'height', 'id', 'patternContentUnits', 'patternTransform', 'patternUnits', 'requiredFeatures', 'style', 'systemLanguage', 'viewBox', 'width', 'x', 'xlink:href', 'y'],
polygon: ['class', 'clip-path', 'clip-rule', 'id', 'fill', 'fill-opacity', 'fill-rule', 'filter', 'id', 'class', 'marker-end', 'marker-mid', 'marker-start', 'mask', 'opacity', 'points', 'requiredFeatures', 'stroke', 'stroke-dasharray', 'stroke-dashoffset', 'stroke-linecap', 'stroke-linejoin', 'stroke-miterlimit', 'stroke-opacity', 'stroke-width', 'style', 'systemLanguage', 'transform'],
polyline: ['class', 'clip-path', 'clip-rule', 'id', 'fill', 'fill-opacity', 'fill-rule', 'filter', 'marker-end', 'marker-mid', 'marker-start', 'mask', 'opacity', 'points', 'requiredFeatures', 'stroke', 'stroke-dasharray', 'stroke-dashoffset', 'stroke-linecap', 'stroke-linejoin', 'stroke-miterlimit', 'stroke-opacity', 'stroke-width', 'style', 'systemLanguage', 'transform'],
radialGradient: ['class', 'cx', 'cy', 'fx', 'fy', 'gradientTransform', 'gradientUnits', 'id', 'r', 'requiredFeatures', 'spreadMethod', 'systemLanguage', 'xlink:href'],
rect: ['class', 'clip-path', 'clip-rule', 'fill', 'fill-opacity', 'fill-rule', 'filter', 'height', 'id', 'mask', 'opacity', 'requiredFeatures', 'rx', 'ry', 'stroke', 'stroke-dasharray', 'stroke-dashoffset', 'stroke-linecap', 'stroke-linejoin', 'stroke-miterlimit', 'stroke-opacity', 'stroke-width', 'style', 'systemLanguage', 'transform', 'width', 'x', 'y'],
stop: ['class', 'id', 'offset', 'requiredFeatures', 'stop-color', 'stop-opacity', 'style', 'systemLanguage'],
svg: ['class', 'clip-path', 'clip-rule', 'filter', 'id', 'height', 'mask', 'preserveAspectRatio', 'requiredFeatures', 'style', 'systemLanguage', 'viewBox', 'width', 'x', 'xmlns', 'xmlns:se', 'xmlns:xlink', 'y'],
switch: ['class', 'id', 'requiredFeatures', 'systemLanguage'],
symbol: ['class', 'fill', 'fill-opacity', 'fill-rule', 'filter', 'font-family', 'font-size', 'font-style', 'font-weight', 'id', 'opacity', 'preserveAspectRatio', 'requiredFeatures', 'stroke', 'stroke-dasharray', 'stroke-dashoffset', 'stroke-linecap', 'stroke-linejoin', 'stroke-miterlimit', 'stroke-opacity', 'stroke-width', 'style', 'systemLanguage', 'transform', 'viewBox'],
text: ['class', 'clip-path', 'clip-rule', 'fill', 'fill-opacity', 'fill-rule', 'filter', 'font-family', 'font-size', 'font-style', 'font-weight', 'id', 'mask', 'opacity', 'requiredFeatures', 'stroke', 'stroke-dasharray', 'stroke-dashoffset', 'stroke-linecap', 'stroke-linejoin', 'stroke-miterlimit', 'stroke-opacity', 'stroke-width', 'style', 'systemLanguage', 'text-anchor', 'transform', 'x', 'xml:space', 'y'],
textPath: ['class', 'id', 'method', 'requiredFeatures', 'spacing', 'startOffset', 'style', 'systemLanguage', 'transform', 'xlink:href'],
title: [],
tspan: ['class', 'clip-path', 'clip-rule', 'dx', 'dy', 'fill', 'fill-opacity', 'fill-rule', 'filter', 'font-family', 'font-size', 'font-style', 'font-weight', 'id', 'mask', 'opacity', 'requiredFeatures', 'rotate', 'stroke', 'stroke-dasharray', 'stroke-dashoffset', 'stroke-linecap', 'stroke-linejoin', 'stroke-miterlimit', 'stroke-opacity', 'stroke-width', 'style', 'systemLanguage', 'text-anchor', 'textLength', 'transform', 'x', 'xml:space', 'y'],
use: ['class', 'clip-path', 'clip-rule', 'fill', 'fill-opacity', 'fill-rule', 'filter', 'height', 'id', 'mask', 'stroke', 'stroke-dasharray', 'stroke-dashoffset', 'stroke-linecap', 'stroke-linejoin', 'stroke-miterlimit', 'stroke-opacity', 'stroke-width', 'style', 'transform', 'width', 'x', 'xlink:href', 'y'],
// MathML Elements
annotation: ['encoding'],
'annotation-xml': ['encoding'],
maction: ['actiontype', 'other', 'selection'],
math: ['class', 'id', 'display', 'xmlns'],
menclose: ['notation'],
merror: [],
mfrac: ['linethickness'],
mi: ['mathvariant'],
mmultiscripts: [],
mn: [],
mo: ['fence', 'lspace', 'maxsize', 'minsize', 'rspace', 'stretchy'],
mover: [],
mpadded: ['lspace', 'width', 'height', 'depth', 'voffset'],
mphantom: [],
mprescripts: [],
mroot: [],
mrow: ['xlink:href', 'xlink:type', 'xmlns:xlink'],
mspace: ['depth', 'height', 'width'],
msqrt: [],
mstyle: ['displaystyle', 'mathbackground', 'mathcolor', 'mathvariant', 'scriptlevel'],
msub: [],
msubsup: [],
msup: [],
mtable: ['align', 'columnalign', 'columnlines', 'columnspacing', 'displaystyle', 'equalcolumns', 'equalrows', 'frame', 'rowalign', 'rowlines', 'rowspacing', 'width'],
mtd: ['columnalign', 'columnspan', 'rowalign', 'rowspan'],
mtext: [],
mtr: ['columnalign', 'rowalign'],
munder: [],
munderover: [],
none: [],
semantics: []
};
// Produce a Namespace-aware version of svgWhitelist
const svgWhiteListNS_ = {};
Object.entries(svgWhiteList_).forEach(function ([elt, atts]) {
const attNS = {};
Object.entries(atts).forEach(function ([i, att]) {
if (att.includes(':')) {
const v = att.split(':');
attNS[v[1]] = NS[(v[0]).toUpperCase()];
} else {
attNS[att] = att === 'xmlns' ? NS.XMLNS : null;
}
});
svgWhiteListNS_[elt] = attNS;
});
/**
* Sanitizes the input node and its children.
* It only keeps what is allowed from our whitelist defined above.
* @function module:sanitize.sanitizeSvg
* @param {Text|Element} node - The DOM element to be checked (we'll also check its children) or text node to be cleaned up
* @returns {void}
*/
export const sanitizeSvg = function (node) {
// Cleanup text nodes
if (node.nodeType === 3) { // 3 === TEXT_NODE
// Trim whitespace
node.nodeValue = node.nodeValue.replace(/^\s+|\s+$/g, '');
// Remove if empty
if (!node.nodeValue.length) {
node.remove();
}
}
// We only care about element nodes.
// Automatically return for all non-element nodes, such as comments, etc.
if (node.nodeType !== 1) { // 1 == ELEMENT_NODE
return;
}
const doc = node.ownerDocument;
const parent = node.parentNode;
// can parent ever be null here? I think the root node's parent is the document...
if (!doc || !parent) {
return;
}
const allowedAttrs = svgWhiteList_[node.nodeName];
const allowedAttrsNS = svgWhiteListNS_[node.nodeName];
// if this element is supported, sanitize it
if (typeof allowedAttrs !== 'undefined') {
const seAttrs = [];
let i = node.attributes.length;
while (i--) {
// if the attribute is not in our whitelist, then remove it
// could use jQuery's inArray(), but I don't know if that's any better
const attr = node.attributes.item(i);
const attrName = attr.nodeName;
const attrLocalName = attr.localName;
const attrNsURI = attr.namespaceURI;
// Check that an attribute with the correct localName in the correct namespace is on
// our whitelist or is a namespace declaration for one of our allowed namespaces
if (!({}.hasOwnProperty.call(allowedAttrsNS, attrLocalName) && attrNsURI === allowedAttrsNS[attrLocalName] && attrNsURI !== NS.XMLNS) &&
!(attrNsURI === NS.XMLNS && REVERSE_NS[attr.value])) {
// TODO(codedread): Programmatically add the se: attributes to the NS-aware whitelist.
// Bypassing the whitelist to allow se: prefixes.
// Is there a more appropriate way to do this?
if (attrName.startsWith('se:') || attrName.startsWith('data-')) {
seAttrs.push([attrName, attr.value]);
}
node.removeAttributeNS(attrNsURI, attrLocalName);
}
// Add spaces before negative signs where necessary
if (isGecko()) {
switch (attrName) {
case 'transform':
case 'gradientTransform':
case 'patternTransform': {
const val = attr.value.replace(/(\d)-/g, '$1 -');
// const val = attr.value.replace(/(?<digit>\d)-/g, '$<digit> -');
node.setAttribute(attrName, val);
break;
}
}
}
// For the style attribute, rewrite it in terms of XML presentational attributes
if (attrName === 'style') {
const props = attr.value.split(';');
let p = props.length;
while (p--) {
const [name, val] = props[p].split(':');
const styleAttrName = (name || '').trim();
const styleAttrVal = (val || '').trim();
// Now check that this attribute is supported
if (allowedAttrs.includes(styleAttrName)) {
node.setAttribute(styleAttrName, styleAttrVal);
}
}
node.removeAttribute('style');
}
}
Object.values(seAttrs).forEach(([att, val]) => {
node.setAttributeNS(NS.SE, att, val);
});
// for some elements that have a xlink:href, ensure the URI refers to a local element
// (but not for links)
const href = getHref(node);
if (href &&
['filter', 'linearGradient', 'pattern',
'radialGradient', 'textPath', 'use'].includes(node.nodeName)) {
// TODO: we simply check if the first character is a #, is this bullet-proof?
if (href[0] !== '#') {
// remove the attribute (but keep the element)
setHref(node, '');
node.removeAttributeNS(NS.XLINK, 'href');
}
}
// Safari crashes on a <use> without a xlink:href, so we just remove the node here
if (node.nodeName === 'use' && !getHref(node)) {
node.remove();
return;
}
// if the element has attributes pointing to a non-local reference,
// need to remove the attribute
Object.values(['clip-path', 'fill', 'filter', 'marker-end', 'marker-mid', 'marker-start', 'mask', 'stroke'], function (attr) {
let val = node.getAttribute(attr);
if (val) {
val = getUrlFromAttr(val);
// simply check for first character being a '#'
if (val && val[0] !== '#') {
node.setAttribute(attr, '');
node.removeAttribute(attr);
}
}
});
// recurse to children
i = node.childNodes.length;
while (i--) { sanitizeSvg(node.childNodes.item(i)); }
// else (element not supported), remove it
} else {
// remove all children from this node and insert them before this node
// TODO: in the case of animation elements this will hardly ever be correct
const children = [];
while (node.hasChildNodes()) {
children.push(parent.insertBefore(node.firstChild, node));
}
// remove this node from the document altogether
node.remove();
// call sanitizeSvg on each of those children
let i = children.length;
while (i--) { sanitizeSvg(children[i]); }
}
};