Swift: Check the options flag contains .regularExpression.

Author: geoffw0

swift/ql/lib/codeql/swift/regex/Regex.qll

@@ -391,8 +391,15 @@ private class SometimesRegexEval extends RegexEval {
     ) and
     regexInput.asExpr() = this.getArgument(0).getExpr() and
     stringInput.asExpr() = this.getQualifier() and
-    optionsInput.asExpr() = this.getArgumentWithLabel("options").getExpr()
-    // TODO: check options may have value `.regularExpression`
+    optionsInput.asExpr() = this.getArgumentWithLabel("options").getExpr() and
+    // flow from `.regularExpression` to `options` argument
+    exists(MemberRefExpr sourceValue |
+      sourceValue
+          .getMember()
+          .(FieldDecl)
+          .hasQualifiedName("NSString.CompareOptions", "regularExpression") and
+      DataFlow::localFlow(DataFlow::exprNode(sourceValue), optionsInput)
+    )
   }
 
   override DataFlow::Node getRegexInput() { result = regexInput }

swift/ql/test/library-tests/regex/parse.expected

@@ -6334,21 +6334,11 @@ regex.swift:
 #  129| [RegExpStar] .*
 #-----| 0 -> [RegExpDot] .
 
-#  130| [RegExpDot] .
-
-#  130| [RegExpStar] .*
-#-----| 0 -> [RegExpDot] .
-
 #  131| [RegExpDot] .
 
 #  131| [RegExpStar] .*
 #-----| 0 -> [RegExpDot] .
 
-#  132| [RegExpDot] .
-
-#  132| [RegExpStar] .*
-#-----| 0 -> [RegExpDot] .
-
 #  136| [RegExpDot] .
 
 #  136| [RegExpStar] .*
@@ -6359,36 +6349,16 @@ regex.swift:
 #  150| [RegExpStar] .*
 #-----| 0 -> [RegExpDot] .
 
-#  151| [RegExpDot] .
-
-#  151| [RegExpStar] .*
-#-----| 0 -> [RegExpDot] .
-
 #  152| [RegExpDot] .
 
 #  152| [RegExpStar] .*
 #-----| 0 -> [RegExpDot] .
 
-#  153| [RegExpDot] .
-
-#  153| [RegExpStar] .*
-#-----| 0 -> [RegExpDot] .
-
-#  154| [RegExpDot] .
-
-#  154| [RegExpStar] .*
-#-----| 0 -> [RegExpDot] .
-
 #  155| [RegExpDot] .
 
 #  155| [RegExpStar] .*
 #-----| 0 -> [RegExpDot] .
 
-#  156| [RegExpDot] .
-
-#  156| [RegExpStar] .*
-#-----| 0 -> [RegExpDot] .
-
 #  160| [RegExpDot] .
 
 #  160| [RegExpStar] .*
@@ -6643,23 +6613,3 @@ regex.swift:
 
 #  246| [RegExpStar] .*
 #-----| 0 -> [RegExpDot] .
-
-#  251| [RegExpDot] .
-
-#  251| [RegExpStar] .*
-#-----| 0 -> [RegExpDot] .
-
-#  252| [RegExpDot] .
-
-#  252| [RegExpStar] .*
-#-----| 0 -> [RegExpDot] .
-
-#  253| [RegExpDot] .
-
-#  253| [RegExpStar] .*
-#-----| 0 -> [RegExpDot] .
-
-#  254| [RegExpDot] .
-
-#  254| [RegExpStar] .*
-#-----| 0 -> [RegExpDot] .

swift/ql/test/library-tests/regex/regex.swift

@@ -127,9 +127,9 @@ func myRegexpMethodsTests(b: Bool, str_unknown: String) throws {
 	// --- StringProtocol ---
 
 	_ = input.range(of: ".*", options: .regularExpression, range: nil, locale: nil) // $ regex=.* input=input
-	_ = input.range(of: ".*", options: .literal, range: nil, locale: nil) // $ SPURIOUS: regex=.* input=input
+	_ = input.range(of: ".*", options: .literal, range: nil, locale: nil) // (not a regular expression)
 	_ = input.replacingOccurrences(of: ".*", with: "", options: .regularExpression) // $ regex=.* input=input
-	_ = input.replacingOccurrences(of: ".*", with: "", options: .literal) // $ SPURIOUS: regex=.* input=input
+	_ = input.replacingOccurrences(of: ".*", with: "", options: .literal) // (not a regular expression)
 
 	// --- NSRegularExpression ---
 
@@ -148,12 +148,12 @@ func myRegexpMethodsTests(b: Bool, str_unknown: String) throws {
 	let regexOptions = NSString.CompareOptions.regularExpression
 	let regexOptions2 : NSString.CompareOptions = [.regularExpression, .caseInsensitive]
 	_ = inputNS.range(of: ".*", options: .regularExpression) // $ regex=.* input=inputNS
-	_ = inputNS.range(of: ".*", options: [.regularExpression]) // $ regex=.* input=inputNS
+	_ = inputNS.range(of: ".*", options: [.regularExpression]) // $ MISSING: regex=.* input=inputNS
 	_ = inputNS.range(of: ".*", options: regexOptions) // $ regex=.* input=inputNS
-	_ = inputNS.range(of: ".*", options: regexOptions2) // $ regex=.* input=inputNS
-	_ = inputNS.range(of: ".*", options: .literal) // $ SPURIOUS: regex=.* input=inputNS
+	_ = inputNS.range(of: ".*", options: regexOptions2) // $ MISSING: regex=.* input=inputNS
+	_ = inputNS.range(of: ".*", options: .literal) // (not a regular expression)
 	_ = inputNS.replacingOccurrences(of: ".*", with: "", options: .regularExpression, range: NSMakeRange(0, inputNS.length)) // $ regex=.* input=inputNS
-	_ = inputNS.replacingOccurrences(of: ".*", with: "", options: .literal, range: NSMakeRange(0, inputNS.length)) // $ SPURIOUS: regex=.* input=inputNS
+	_ = inputNS.replacingOccurrences(of: ".*", with: "", options: .literal, range: NSMakeRange(0, inputNS.length)) // (not a regular expression)
 
 	// --- flow ---
 
@@ -248,8 +248,8 @@ func myRegexpMethodsTests(b: Bool, str_unknown: String) throws {
 	// parse modes set through other methods
 
 	let myOptions2 : NSString.CompareOptions = [.regularExpression, .caseInsensitive]
-    _ = input.replacingOccurrences(of: ".*", with: "", options: [.regularExpression, .caseInsensitive]) // $ regex=.* input=input MISSING: modes=IGNORECASE
-    _ = input.replacingOccurrences(of: ".*", with: "", options: myOptions2) // $ regex=.* input=input MISSING: modes=IGNORECASE
-    _ = NSString(string: "abc").replacingOccurrences(of: ".*", with: "", options: [.regularExpression, .caseInsensitive], range: NSMakeRange(0, inputNS.length)) // $ regex=.* input="call to NSString.init(string:)" MISSING: modes=IGNORECASE
-    _ = NSString(string: "abc").replacingOccurrences(of: ".*", with: "", options: myOptions2, range: NSMakeRange(0, inputNS.length)) // $ regex=.* input="call to NSString.init(string:)" MISSING: modes=IGNORECASE
+    _ = input.replacingOccurrences(of: ".*", with: "", options: [.regularExpression, .caseInsensitive]) // $ MISSING: regex=.* input=input modes=IGNORECASE
+    _ = input.replacingOccurrences(of: ".*", with: "", options: myOptions2) // $ MISSING: regex=.* input=input modes=IGNORECASE
+    _ = NSString(string: "abc").replacingOccurrences(of: ".*", with: "", options: [.regularExpression, .caseInsensitive], range: NSMakeRange(0, inputNS.length)) // $ MISSING: regex=.* input="call to NSString.init(string:)" modes=IGNORECASE
+    _ = NSString(string: "abc").replacingOccurrences(of: ".*", with: "", options: myOptions2, range: NSMakeRange(0, inputNS.length)) // $ MISSING: regex=.* input="call to NSString.init(string:)" modes=IGNORECASE
 }