pam-moduler: Add test that generates a new debug module and verify it works

We mimic what pam_debug.so does by default, by implementing a similar
module fully in go, generated using pam-moduler.

This requires various utilities to generate the module and run the tests
that are in a separate internal modules so that it can be shared between
multiple implementations

cmd/pam-moduler/tests/internal/utils/base-module.go

@@ -0,0 +1,38 @@
+package utils
+
+import "github.com/msteinert/pam/v2"
+
+// BaseModule is the type for a base PAM module.
+type BaseModule struct{}
+
+// AcctMgmt is the handler function for PAM AcctMgmt.
+func (h *BaseModule) AcctMgmt(pam.ModuleTransaction, pam.Flags, []string) error {
+	return nil
+}
+
+// Authenticate is the handler function for PAM Authenticate.
+func (h *BaseModule) Authenticate(pam.ModuleTransaction, pam.Flags, []string) error {
+	return nil
+}
+
+// ChangeAuthTok is the handler function for PAM ChangeAuthTok.
+func (h *BaseModule) ChangeAuthTok(pam.ModuleTransaction, pam.Flags, []string) error {
+	return nil
+}
+
+// OpenSession is the handler function for PAM OpenSession.
+func (h *BaseModule) OpenSession(pam.ModuleTransaction, pam.Flags, []string) error {
+	return nil
+}
+
+// CloseSession is the handler function for PAM CloseSession.
+func (h *BaseModule) CloseSession(pam.ModuleTransaction, pam.Flags, []string) error {
+	return nil
+}
+
+// SetCred is the handler function for PAM SetCred.
+func (h *BaseModule) SetCred(pam.ModuleTransaction, pam.Flags, []string) error {
+	return nil
+}
+
+var _ pam.ModuleHandler = &BaseModule{}