1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
|
/**
* --------------------------------------------------------------------------
* Bootstrap (v5.0.1): util/sanitizer.js
* Licensed under MIT (https://github.com/twbs/bootstrap/blob/main/LICENSE)
* --------------------------------------------------------------------------
*/
const uriAttrs = new Set([
'background',
'cite',
'href',
'itemtype',
'longdesc',
'poster',
'src',
'xlink:href'
])
const ARIA_ATTRIBUTE_PATTERN = /^aria-[\w-]*$/i
/**
* A pattern that recognizes a commonly useful subset of URLs that are safe.
*
* Shoutout to Angular 7 https://github.com/angular/angular/blob/7.2.4/packages/core/src/sanitization/url_sanitizer.ts
*/
const SAFE_URL_PATTERN = /^(?:(?:https?|mailto|ftp|tel|file):|[^#&/:?]*(?:[#/?]|$))/i
/**
* A pattern that matches safe data URLs. Only matches image, video and audio types.
*
* Shoutout to Angular 7 https://github.com/angular/angular/blob/7.2.4/packages/core/src/sanitization/url_sanitizer.ts
*/
const DATA_URL_PATTERN = /^data:(?:image\/(?:bmp|gif|jpeg|jpg|png|tiff|webp)|video\/(?:mpeg|mp4|ogg|webm)|audio\/(?:mp3|oga|ogg|opus));base64,[\d+/a-z]+=*$/i
const allowedAttribute = (attr, allowedAttributeList) => {
const attrName = attr.nodeName.toLowerCase()
if (allowedAttributeList.includes(attrName)) {
if (uriAttrs.has(attrName)) {
return Boolean(SAFE_URL_PATTERN.test(attr.nodeValue) || DATA_URL_PATTERN.test(attr.nodeValue))
}
return true
}
const regExp = allowedAttributeList.filter(attrRegex => attrRegex instanceof RegExp)
// Check if a regular expression validates the attribute.
for (let i = 0, len = regExp.length; i < len; i++) {
if (regExp[i].test(attrName)) {
return true
}
}
return false
}
export const DefaultAllowlist = {
// Global attributes allowed on any supplied element below.
'*': ['class', 'dir', 'id', 'lang', 'role', ARIA_ATTRIBUTE_PATTERN],
a: ['target', 'href', 'title', 'rel'],
area: [],
b: [],
br: [],
col: [],
code: [],
div: [],
em: [],
hr: [],
h1: [],
h2: [],
h3: [],
h4: [],
h5: [],
h6: [],
i: [],
img: ['src', 'srcset', 'alt', 'title', 'width', 'height'],
li: [],
ol: [],
p: [],
pre: [],
s: [],
small: [],
span: [],
sub: [],
sup: [],
strong: [],
u: [],
ul: []
}
export function sanitizeHtml(unsafeHtml, allowList, sanitizeFn) {
if (!unsafeHtml.length) {
return unsafeHtml
}
if (sanitizeFn && typeof sanitizeFn === 'function') {
return sanitizeFn(unsafeHtml)
}
const domParser = new window.DOMParser()
const createdDocument = domParser.parseFromString(unsafeHtml, 'text/html')
const allowlistKeys = Object.keys(allowList)
const elements = [].concat(...createdDocument.body.querySelectorAll('*'))
for (let i = 0, len = elements.length; i < len; i++) {
const el = elements[i]
const elName = el.nodeName.toLowerCase()
if (!allowlistKeys.includes(elName)) {
el.remove()
continue
}
const attributeList = [].concat(...el.attributes)
const allowedAttributes = [].concat(allowList['*'] || [], allowList[elName] || [])
attributeList.forEach(attr => {
if (!allowedAttribute(attr, allowedAttributes)) {
el.removeAttribute(attr.nodeName)
}
})
}
return createdDocument.body.innerHTML
}
|