Swift: Add and use AbstractFunctionDecl.hasGlobalName predicate.

Author: geoffw0

swift/ql/lib/codeql/swift/elements/decl/AbstractFunctionDecl.qll

@@ -1,4 +1,5 @@
 private import codeql.swift.generated.decl.AbstractFunctionDecl
+private import codeql.swift.elements.decl.MethodDecl
 
 class AbstractFunctionDecl extends Generated::AbstractFunctionDecl {
   override string toString() { result = this.getName() }
@@ -7,4 +8,12 @@ class AbstractFunctionDecl extends Generated::AbstractFunctionDecl {
    * Holds if this function is called `funcName`.
    */
   predicate hasName(string funcName) { this.getName() = funcName }
+
+  /**
+   * Holds if this is a global (non-member) function called `funcName`.
+   */
+  predicate hasGlobalName(string funcName) {
+    this.hasName(funcName) and
+    not this instanceof MethodDecl
+  }
 }

swift/ql/src/queries/Security/CWE-089/SqlInjection.ql

@@ -27,15 +27,14 @@ abstract class SqlSink extends DataFlow::Node { }
 class CApiSqlSink extends SqlSink {
   CApiSqlSink() {
     // `sqlite3_exec` and variants of `sqlite3_prepare`.
-    exists(AbstractFunctionDecl f, CallExpr call |
-      f.getName() =
-        [
-          "sqlite3_exec(_:_:_:_:_:)", "sqlite3_prepare(_:_:_:_:_:)",
-          "sqlite3_prepare_v2(_:_:_:_:_:)", "sqlite3_prepare_v3(_:_:_:_:_:_:)",
-          "sqlite3_prepare16(_:_:_:_:_:)", "sqlite3_prepare16_v2(_:_:_:_:_:)",
-          "sqlite3_prepare16_v3(_:_:_:_:_:_:)"
-        ] and
-      call.getStaticTarget() = f and
+    exists(CallExpr call |
+      call.getStaticTarget()
+          .hasGlobalName([
+              "sqlite3_exec(_:_:_:_:_:)", "sqlite3_prepare(_:_:_:_:_:)",
+              "sqlite3_prepare_v2(_:_:_:_:_:)", "sqlite3_prepare_v3(_:_:_:_:_:_:)",
+              "sqlite3_prepare16(_:_:_:_:_:)", "sqlite3_prepare16_v2(_:_:_:_:_:)",
+              "sqlite3_prepare16_v3(_:_:_:_:_:_:)"
+            ]) and
       call.getArgument(1).getExpr() = this.asExpr()
     )
   }