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# frozen_string_literal: true
RSpec.shared_examples 'default whitelist' do
it 'sanitizes tags that are not whitelisted' do
act = %q{<textarea>no inputs</textarea> and <blink>no blinks</blink>}
exp = 'no inputs and no blinks'
expect(filter(act).to_html).to eq exp
end
it 'sanitizes tag attributes' do
act = %q{<a href="http://example.com/bar.html" onclick="bar">Text</a>}
exp = %q{<a href="http://example.com/bar.html">Text</a>}
expect(filter(act).to_html).to eq exp
end
it 'sanitizes javascript in attributes' do
act = %q(<a href="javascript:alert('foo')">Text</a>)
exp = '<a>Text</a>'
expect(filter(act).to_html).to eq exp
end
it 'sanitizes mixed-cased javascript in attributes' do
act = %q(<a href="javaScript:alert('foo')">Text</a>)
exp = '<a>Text</a>'
expect(filter(act).to_html).to eq exp
end
it 'allows whitelisted HTML tags from the user' do
exp = act = "<dl>\n<dt>Term</dt>\n<dd>Definition</dd>\n</dl>"
expect(filter(act).to_html).to eq exp
end
it 'sanitizes `class` attribute on any element' do
act = %q{<strong class="foo">Strong</strong>}
expect(filter(act).to_html).to eq %q{<strong>Strong</strong>}
end
it 'sanitizes `id` attribute on any element' do
act = %q{<em id="foo">Emphasis</em>}
expect(filter(act).to_html).to eq %q{<em>Emphasis</em>}
end
end
RSpec.shared_examples 'XSS prevention' do
# Adapted from the Sanitize test suite: http://git.io/vczrM
protocols = {
'protocol-based JS injection: simple, no spaces' => {
input: '<a href="javascript:alert(\'XSS\');">foo</a>',
output: '<a>foo</a>'
},
'protocol-based JS injection: simple, spaces before' => {
input: '<a href="javascript :alert(\'XSS\');">foo</a>',
output: '<a>foo</a>'
},
'protocol-based JS injection: simple, spaces after' => {
input: '<a href="javascript: alert(\'XSS\');">foo</a>',
output: '<a>foo</a>'
},
'protocol-based JS injection: simple, spaces before and after' => {
input: '<a href="javascript : alert(\'XSS\');">foo</a>',
output: '<a>foo</a>'
},
'protocol-based JS injection: preceding colon' => {
input: '<a href=":javascript:alert(\'XSS\');">foo</a>',
output: '<a>foo</a>'
},
'protocol-based JS injection: UTF-8 encoding' => {
input: '<a href="javascript:">foo</a>',
output: '<a>foo</a>'
},
'protocol-based JS injection: long UTF-8 encoding' => {
input: '<a href="javascript:">foo</a>',
output: '<a>foo</a>'
},
'protocol-based JS injection: long UTF-8 encoding without semicolons' => {
input: '<a href=javascript:alert('XSS')>foo</a>',
output: '<a>foo</a>'
},
'protocol-based JS injection: hex encoding' => {
input: '<a href="javascript:">foo</a>',
output: '<a>foo</a>'
},
'protocol-based JS injection: long hex encoding' => {
input: '<a href="javascript:">foo</a>',
output: '<a>foo</a>'
},
'protocol-based JS injection: hex encoding without semicolons' => {
input: '<a href=javascript:alert('XSS')>foo</a>',
output: '<a>foo</a>'
},
'protocol-based JS injection: null char' => {
input: "<a href=java\0script:alert(\"XSS\")>foo</a>",
output: '<a href="java"></a>'
},
'protocol-based JS injection: invalid URL char' => {
input: '<img src=java\script:alert("XSS")>',
output: '<img>'
},
'protocol-based JS injection: Unicode' => {
input: %Q(<a href="\u0001java\u0003script:alert('XSS')">foo</a>),
output: '<a>foo</a>'
},
'protocol-based JS injection: spaces and entities' => {
input: '<a href="  javascript:alert(\'XSS\');">foo</a>',
output: '<a href="">foo</a>'
},
'protocol whitespace' => {
input: '<a href=" http://example.com/"></a>',
output: '<a href="http://example.com/"></a>'
}
}
protocols.each do |name, data|
it "disallows #{name}" do
doc = filter(data[:input])
expect(doc.to_html).to eq data[:output]
end
end
it 'disallows data links' do
input = '<a href="data:text/html;base64,PHNjcmlwdD5hbGVydCgnWFNTJyk8L3NjcmlwdD4K">XSS</a>'
output = filter(input)
expect(output.to_html).to eq '<a>XSS</a>'
end
it 'disallows vbscript links' do
input = '<a href="vbscript:alert(document.domain)">XSS</a>'
output = filter(input)
expect(output.to_html).to eq '<a>XSS</a>'
end
end
RSpec.shared_examples 'sanitize link' do
it 'removes `rel` attribute from `a` elements' do
act = %q{<a href="#" rel="nofollow">Link</a>}
exp = %q{<a href="#">Link</a>}
expect(filter(act).to_html).to eq exp
end
it 'disallows invalid URIs' do
expect(Addressable::URI).to receive(:parse).with('foo://example.com')
.and_raise(Addressable::URI::InvalidURIError)
input = '<a href="foo://example.com">Foo</a>'
output = filter(input)
expect(output.to_html).to eq '<a>Foo</a>'
end
it 'allows non-standard anchor schemes' do
exp = %q{<a href="irc://irc.freenode.net/git">IRC</a>}
act = filter(exp)
expect(act.to_html).to eq exp
end
it 'allows relative links' do
exp = %q{<a href="foo/bar.md">foo/bar.md</a>}
act = filter(exp)
expect(act.to_html).to eq exp
end
end
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