Add a test suite

.travis.yml

@@ -7,3 +7,6 @@ go:
 before_install:
   - sudo apt-get update -qq
   - sudo apt-get install -qq --no-install-recommends libpam0g-dev
+  - sudo useradd -d /tmp/test -p '$1$Qd8H95T5$RYSZQeoFbEB.gS19zS99A0' -s /bin/false test
+
+script: sudo go test -v ./...

README.md

@@ -11,5 +11,15 @@ There's an example of a "fake login" program in the examples directory.
 Look at the pam module's [godocs][1] for details about the Go API, or refer
 to the official [PAM documentation][2].
 
+The test suite must be run as the root user. To setup your system for testing,
+create a user named "test" with the password "secret". For example:
+
+```
+$ sudo useradd test \
+    -d /tmp/test \
+    -p '$1$Qd8H95T5$RYSZQeoFbEB.gS19zS99A0' \
+    -s /bin/false
+```
+
 [1]: http://godoc.org/github.com/msteinert/pam
 [2]: http://www.kernel.org/pub/linux/libs/pam/Linux-PAM-html/adg-interface-by-app-expected.html

transaction.go

@@ -106,7 +106,7 @@ func Start(service, user string, handler ConversationHandler) (*Transaction, err
 	var u *C.char
 	if len(user) != 0 {
 		u = C.CString(user)
-		defer C.free(unsafe.Pointer(s))
+		defer C.free(unsafe.Pointer(u))
 	}
 	t.status = C.pam_start(s, u, t.conv.conv, &t.handle)
 	if t.status != C.PAM_SUCCESS {

transaction_test.go

@@ -0,0 +1,82 @@
+package pam
+
+import (
+	"errors"
+	"testing"
+)
+
+func TestPAM_001(t *testing.T) {
+	tx, err := StartFunc("", "test", func(s Style, msg string) (string, error) {
+		return "secret", nil
+	})
+	if err != nil {
+		t.Fatalf("start #error: %v", err)
+	}
+	err = tx.Authenticate(0)
+	if err != nil {
+		t.Fatalf("authenticate #error: %v", err)
+	}
+}
+
+func TestPAM_002(t *testing.T) {
+	tx, err := StartFunc("", "", func(s Style, msg string) (string, error) {
+		switch s {
+		case PromptEchoOn:
+			return "test", nil
+		case PromptEchoOff:
+			return "secret", nil
+		}
+		return "", errors.New("unexpected")
+	})
+	if err != nil {
+		t.Fatalf("start #error: %v", err)
+	}
+	err = tx.Authenticate(0)
+	if err != nil {
+		t.Fatalf("authenticate #error: %v", err)
+	}
+}
+
+type Credentials struct {
+	User     string
+	Password string
+}
+
+func (c Credentials) RespondPAM(s Style, msg string) (string, error) {
+	switch s {
+	case PromptEchoOn:
+		return c.User, nil
+	case PromptEchoOff:
+		return c.Password, nil
+	}
+	return "", errors.New("unexpected")
+}
+
+func TestPAM_003(t *testing.T) {
+	c := Credentials{
+		User:     "test",
+		Password: "secret",
+	}
+	tx, err := Start("", "", c)
+	if err != nil {
+		t.Fatalf("start #error: %v", err)
+	}
+	err = tx.Authenticate(0)
+	if err != nil {
+		t.Fatalf("authenticate #error: %v", err)
+	}
+}
+
+func TestPAM_004(t *testing.T) {
+	c := Credentials{
+		Password: "secret",
+	}
+	tx, err := Start("", "test", c)
+	if err != nil {
+		t.Fatalf("start #error: %v", err)
+	}
+	err = tx.Authenticate(0)
+	if err != nil {
+		t.Fatalf("authenticate #error: %v", err)
+	}
+}