Swift: Add tests for bad tag filter query.

swift/ql/test/query-tests/Security/CWE-116/BadTagFilter.qlref

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+queries/Security/CWE-116/BadTagFilter.ql

swift/ql/test/query-tests/Security/CWE-116/test.swift

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+
+// --- stubs ---
+
+struct URL {
+    init?(string: String) {}
+}
+
+extension String {
+    init(contentsOf: URL) {
+        let data = ""
+        self.init(data)
+    }
+}
+
+struct AnyRegexOutput {
+}
+
+protocol RegexComponent<RegexOutput> {
+	associatedtype RegexOutput
+}
+
+struct Regex<Output> : RegexComponent {
+	struct Match {
+	}
+
+	init(_ pattern: String) throws where Output == AnyRegexOutput { }
+
+    func ignoresCase(_ ignoresCase: Bool = true) -> Regex<Regex<Output>.RegexOutput> { return self }
+    func dotMatchesNewlines(_ dotMatchesNewlines: Bool = true) -> Regex<Regex<Output>.RegexOutput> { return self }
+
+	func firstMatch(in string: String) throws -> Regex<Output>.Match? { return nil}
+
+	typealias RegexOutput = Output
+}
+
+extension String : RegexComponent {
+	typealias Output = Substring
+	typealias RegexOutput = String.Output
+}
+
+class NSObject {
+}
+
+struct _NSRange {
+	init(location: Int, length: Int) { }
+}
+
+typealias NSRange = _NSRange
+
+func NSMakeRange(_ loc: Int, _ len: Int) -> NSRange { return NSRange(location: loc, length: len) }
+
+class NSTextCheckingResult : NSObject {
+}
+
+class NSRegularExpression : NSObject {
+	struct Options : OptionSet {
+	    var rawValue: UInt
+
+		static var caseInsensitive: NSRegularExpression.Options { get { return Options(rawValue: 1) } }
+	}
+
+	struct MatchingOptions : OptionSet {
+	    var rawValue: UInt
+	}
+
+	init(pattern: String, options: NSRegularExpression.Options = []) throws { }
+
+	func matches(in string: String, options: NSRegularExpression.MatchingOptions = [], range: NSRange) -> [NSTextCheckingResult] { return [] }
+	func firstMatch(in string: String, options: NSRegularExpression.MatchingOptions = [], range: NSRange) -> NSTextCheckingResult? { return nil }
+}
+
+// --- tests ---
+
+func myRegexpVariantsTests(myUrl: URL) throws {
+    let tainted = String(contentsOf: myUrl) // tainted
+
+    // BAD - doesn't match newlines or `</script >`
+    let re1 = try Regex(#"<script.*?>.*?<\/script>"#).ignoresCase(true)
+    _ = try re1.firstMatch(in: tainted)
+
+    // BAD - doesn't match `</script >`
+    let re2 = try Regex(#"<script.*?>.*?<\/script>/is"#).ignoresCase(true)
+    _ = try re2.firstMatch(in: tainted)
+
+    // GOOD
+    let re3 = try Regex(#"<script.*?>.*?<\/script[^>]*>"#).ignoresCase(true).dotMatchesNewlines(true)
+    _ = try re3.firstMatch(in: tainted)
+
+    // GOOD - we don't care regexps that only match comments
+    let re4 = try Regex(#"<!--.*-->"#).ignoresCase(true).dotMatchesNewlines(true)
+    _ = try re4.firstMatch(in: tainted)
+
+    // GOOD
+    let re5 = try Regex(#"<!--.*--!?>"#).ignoresCase(true).dotMatchesNewlines(true)
+    _ = try re5.firstMatch(in: tainted)
+
+    // BAD, does not match newlines
+    let re6 = try Regex(#"<!--.*--!?>"#).ignoresCase(true)
+    _ = try re6.firstMatch(in: tainted)
+
+    // BAD - doesn't match inside the script tag
+    let re7 = try Regex(#"<script.*?>(.|\s)*?<\/script[^>]*>"#).ignoresCase(true)
+    _ = try re7.firstMatch(in: tainted)
+
+    // BAD - doesn't match newlines inside the content
+    let re8 = try Regex(#"<script[^>]*?>.*?<\/script[^>]*>"#).ignoresCase(true)
+    _ = try re8.firstMatch(in: tainted)
+
+    // BAD - does not match single quotes for attribute values
+    let re9 = try Regex(#"<script(\s|\w|=|")*?>.*?<\/script[^>]*>"#).ignoresCase(true).dotMatchesNewlines(true)
+    _ = try re9.firstMatch(in: tainted)
+
+    // BAD - does not match double quotes for attribute values
+    let re10 = try Regex(#"<script(\s|\w|=|')*?>.*?<\/script[^>]*>"#).ignoresCase(true).dotMatchesNewlines(true)
+    _ = try re10.firstMatch(in: tainted)
+
+    // BAD - does not match tabs between attributes
+    let re11 = try Regex(#"<script( |\n|\w|=|'|")*?>.*?<\/script[^>]*>"#).ignoresCase(true).dotMatchesNewlines(true)
+    _ = try re11.firstMatch(in: tainted)
+
+    // BAD - does not match uppercase SCRIPT tags
+    let re12 = try Regex(#"<script.*?>.*?<\/script[^>]*>"#).dotMatchesNewlines(true)
+    _ = try re12.firstMatch(in: tainted)
+
+    // BAD - does not match mixed case script tags
+    let re13 = try Regex(#"<(script|SCRIPT).*?>.*?<\/(script|SCRIPT)[^>]*>"#).dotMatchesNewlines(true)
+    _ = try re13.firstMatch(in: tainted)
+
+    // BAD - doesn't match newlines in the end tag
+    let re14 = try Regex(#"<script[^>]*?>[\s\S]*?<\/script.*>"#).ignoresCase(true)
+    _ = try re14.firstMatch(in: tainted)
+
+    // GOOD
+    let re15 = try Regex(#"<script[^>]*?>[\s\S]*?<\/script[^>]*?>"#).ignoresCase(true)
+    _ = try re15.firstMatch(in: tainted)
+
+    // BAD - doesn't match comments with the right capture groups
+    let re16 = try Regex(#"<(?:!--([\S|\s]*?)-->)|([^\/\s>]+)[\S\s]*?>"#)
+    _ = try re16.firstMatch(in: tainted)
+
+    // BAD - capture groups
+    let re17 = try Regex(#"<(?:(?:\/([^>]+)>)|(?:!--([\S|\s]*?)-->)|(?:([^\/\s>]+)((?:\s+[\w\-:.]+(?:\s*=\s*?(?:(?:"[^"]*")|(?:'[^']*')|[^\s"'\/>]+))?)*)[\S\s]*?(\/?)>))"#)
+    _ = try re17.firstMatch(in: tainted)
+
+    // BAD - too strict matching on the end tag
+    let ns1 = try NSRegularExpression(pattern: #"<script\b[^>]*>([\s\S]*?)<\/script>"#, options: .caseInsensitive)
+    _ = ns1.matches(in: tainted, range: NSMakeRange(0, tainted.utf16.count))
+
+    // BAD - capture groups
+    let ns2 = try NSRegularExpression(pattern: #"(<[a-z\/!$]("[^"]*"|'[^']*'|[^'">])*>|<!(--.*?--\s*)+>)"#, options: .caseInsensitive)
+    _ = ns2.matches(in: tainted, range: NSMakeRange(0, tainted.utf16.count))
+
+    // BAD - capture groups
+    let ns3 = try NSRegularExpression(pattern: #"<(?:(?:!--([\w\W]*?)-->)|(?:!\[CDATA\[([\w\W]*?)\]\]>)|(?:!DOCTYPE([\w\W]*?)>)|(?:\?([^\s\/<>]+) ?([\w\W]*?)[?/]>)|(?:\/([A-Za-z][A-Za-z0-9\-_\:\.]*)>)|(?:([A-Za-z][A-Za-z0-9\-_\:\.]*)((?:\s+[^"'>]+(?:(?:"[^"]*")|(?:'[^']*')|[^>]*))*|\/|\s+)>))"#)
+    _ = ns3.matches(in: tainted, range: NSMakeRange(0, tainted.utf16.count))
+
+    // BAD - capture groups
+    let ns4 = try NSRegularExpression(pattern: #"<!--([\w\W]*?)-->|<([^>]*?)>"#)
+    _ = ns4.matches(in: tainted, range: NSMakeRange(0, tainted.utf16.count))
+
+    // GOOD - it's used with the ignorecase flag
+    let ns5 = try NSRegularExpression(pattern: #"<script([^>]*)>([\\S\\s]*?)<\/script([^>]*)>"#, options: .caseInsensitive)
+    _ = ns5.matches(in: tainted, range: NSMakeRange(0, tainted.utf16.count))
+
+    // BAD - doesn't match --!>
+    let ns6 = try NSRegularExpression(pattern: #"-->"#)
+    _ = ns6.matches(in: tainted, range: NSMakeRange(0, tainted.utf16.count))
+
+    // GOOD
+    let ns7 = try NSRegularExpression(pattern: #"^>|^->|<!--|-->|--!>|<!-$"#)
+    _ = ns7.matches(in: tainted, range: NSMakeRange(0, tainted.utf16.count))
+}