Add tests for mime/multipart sources

Author: owen-mc

Diff for: go/ql/test/library-tests/semmle/go/frameworks/Stdlib/MimeMultipartSources.go

@@ -0,0 +1,11 @@
+package main
+
+import "mime/multipart"
+
+func MimeMultipartSources(fh *multipart.FileHeader, form *multipart.Form) {
+	tainted1, _ := fh.Open()
+	sink(tainted1)    // $ hasValueFlow="tainted1"
+	sink(fh.Filename) // $ hasValueFlow="selection of Filename"
+	sink(fh.Header)   // $ hasValueFlow="selection of Header"
+	sink(form.Value)  // $ hasValueFlow="selection of Value"
+}

Diff for: go/ql/test/library-tests/semmle/go/frameworks/Stdlib/TaintFlows.expected

@@ -0,0 +1,15 @@
+import go
+import TestUtilities.InlineFlowTest
+
+module TestConfig implements DataFlow::ConfigSig {
+  predicate isSource(DataFlow::Node source) {
+    source = any(Function f | f.getName() = "source").getACall().getResult() or
+    source instanceof RemoteFlowSource
+  }
+
+  predicate isSink(DataFlow::Node sink) {
+    sink = any(Function f | f.getName() = "sink").getACall().getAnArgument()
+  }
+}
+
+import FlowTest<TestConfig, TestConfig>

Diff for: go/ql/test/library-tests/semmle/go/frameworks/Stdlib/TaintFlows.ql

@@ -0,0 +1,11 @@
+package main
+
+func main() {}
+
+func source() interface{} {
+	return nil
+}
+
+func sink(v interface{}) {}
+
+func link(from interface{}, into interface{}) {}