Move to stdlib and extend the module for io/ioutil package

Author: gagliardetto

ql/src/semmle/go/frameworks/Stdlib.qll

@@ -146,35 +146,6 @@ module Fmt {
   }
 }
 
-/** Provides models of commonly used functions in the `io/ioutil` package. */
-module IoUtil {
-  private class IoUtilFileSystemAccess extends FileSystemAccess::Range, DataFlow::CallNode {
-    IoUtilFileSystemAccess() {
-      exists(string fn | getTarget().hasQualifiedName("io/ioutil", fn) |
-        fn = "ReadDir" or
-        fn = "ReadFile" or
-        fn = "TempDir" or
-        fn = "TempFile" or
-        fn = "WriteFile"
-      )
-    }
-
-    override DataFlow::Node getAPathArgument() { result = getAnArgument() }
-  }
-
-  /**
-   * A taint model of the `ioutil.ReadAll` function, recording that it propagates taint
-   * from its first argument to its first result.
-   */
-  private class ReadAll extends TaintTracking::FunctionModel {
-    ReadAll() { hasQualifiedName("io/ioutil", "ReadAll") }
-
-    override predicate hasTaintFlow(FunctionInput inp, FunctionOutput outp) {
-      inp.isParameter(0) and outp.isResult(0)
-    }
-  }
-}
-
 /** Provides models of commonly used functions in the `os` package. */
 module OS {
   /**

ql/src/semmle/go/frameworks/stdlib/IoIoutil.qll

@@ -0,0 +1,56 @@
+/**
+ * Provides classes modeling security-relevant aspects of the `io/ioutil` package.
+ */
+
+import go
+
+/** Provides models of commonly used functions in the `io/ioutil` package. */
+module IoIoutil {
+  private class IoUtilFileSystemAccess extends FileSystemAccess::Range, DataFlow::CallNode {
+    IoUtilFileSystemAccess() {
+      exists(string fn | getTarget().hasQualifiedName("io/ioutil", fn) |
+        fn = "ReadDir" or
+        fn = "ReadFile" or
+        fn = "TempDir" or
+        fn = "TempFile" or
+        fn = "WriteFile"
+      )
+    }
+
+    override DataFlow::Node getAPathArgument() { result = getAnArgument() }
+  }
+
+  private class FunctionModels extends TaintTracking::FunctionModel {
+    FunctionInput inp;
+    FunctionOutput outp;
+
+    FunctionModels() {
+      // signature: func NopCloser(r io.Reader) io.ReadCloser
+      hasQualifiedName("io/ioutil", "NopCloser") and
+      (inp.isParameter(0) and outp.isResult())
+      or
+      // signature: func ReadAll(r io.Reader) ([]byte, error)
+      hasQualifiedName("io/ioutil", "ReadAll") and
+      (inp.isParameter(0) and outp.isResult(0))
+    }
+
+    override predicate hasTaintFlow(FunctionInput input, FunctionOutput output) {
+      input = inp and output = outp
+    }
+  }
+
+  private class MethodModels extends TaintTracking::FunctionModel, Method {
+    FunctionInput inp;
+    FunctionOutput outp;
+
+    MethodModels() {
+      // signature: func (Writer).Write(p []byte) (n int, err error)
+      this.implements("io", "Writer", "Write") and
+      (inp.isParameter(0) and outp.isReceiver())
+    }
+
+    override predicate hasTaintFlow(FunctionInput input, FunctionOutput output) {
+      input = inp and output = outp
+    }
+  }
+}