First iteration for tests

internal/engine/experiment/smtp/smtp.go

@@ -8,7 +8,6 @@ import (
 	"net"
 	"net/smtp"
 	"net/url"
-	"strconv"
 	"time"
 
 	"github.com/ooni/probe-cli/v3/internal/engine/experiment/urlgetter"
@@ -26,9 +25,6 @@ var (
 
 	// errInvalidScheme indicates that the scheme is invalid
 	errInvalidScheme = errors.New("scheme must be smtp(s)")
-
-	// errInvalidPort indicates that the port provided could not be parsed as an int
-	errInvalidPort = errors.New("Port number is not a valid integer")
 )
 
 const (
@@ -37,14 +33,16 @@ const (
 )
 
 // Config contains the experiment config.
-type Config struct {
+type Config struct{}
+
+type RuntimeConfig struct {
 	host       string
 	port       string
 	forced_tls bool
 	noop_count uint8
 }
 
-func config(input model.MeasurementTarget) (*Config, error) {
+func config(input model.MeasurementTarget) (*RuntimeConfig, error) {
 	if input == "" {
 		// TODO: static input data (eg. gmail/riseup..)
 		return nil, errNoInputProvided
@@ -68,16 +66,11 @@ func config(input model.MeasurementTarget) (*Config, error) {
 			port = "465"
 		}
 	} else {
-		// Check that requested port is a valid integer
-		_, err := strconv.Atoi(parsed.Port())
-		if err != nil {
-			return nil, errInvalidPort
-		} else {
-			port = parsed.Port()
-		}
+		// Valid port is checked by URL parsing
+		port = parsed.Port()
 	}
 
-	valid_config := Config{
+	valid_config := RuntimeConfig{
 		host:       parsed.Hostname(),
 		forced_tls: parsed.Scheme == "smtps",
 		port:       port,
@@ -321,7 +314,6 @@ func (m Measurer) Run(
 	ctx context.Context, sess model.ExperimentSession,
 	measurement *model.Measurement, callbacks model.ExperimentCallbacks,
 ) error {
-
 	log := sess.Logger()
 	trace := measurexlite.NewTrace(0, measurement.MeasurementStartTimeSaved)
 
@@ -372,7 +364,7 @@ func (m Measurer) Run(
 			}
 
 			// Try EHLO + NoOps
-			if !tcp_session.smtp("localhost", 10) {
+			if !tcp_session.smtp("localhost", config.noop_count) {
 				continue
 			}
 		} else {
@@ -386,7 +378,7 @@ func (m Measurer) Run(
 				continue
 			}
 
-			if !tcp_session.smtp("localhost", 10) {
+			if !tcp_session.smtp("localhost", config.noop_count) {
 				continue
 			}
 		}

internal/engine/experiment/smtp/smtp_test.go

@@ -0,0 +1,185 @@
+package smtp
+
+import (
+	"bufio"
+	"context"
+	"crypto/tls"
+	"errors"
+	"fmt"
+	"net"
+	"strings"
+	"testing"
+
+	"github.com/ooni/probe-cli/v3/internal/engine/mockable"
+	"github.com/ooni/probe-cli/v3/internal/model"
+)
+
+func plaintextListener() net.Listener {
+	l, err := net.Listen("tcp", "127.0.0.1:0")
+	if err != nil {
+		if l, err = net.Listen("tcp6", "[::1]:0"); err != nil {
+			panic(fmt.Sprintf("httptest: failed to listen on a port: %v", err))
+		}
+	}
+	return l
+}
+
+func tlsListener(l net.Listener) net.Listener {
+	return tls.NewListener(l, &tls.Config{})
+}
+
+func listener_addr(l net.Listener) string {
+	return l.Addr().String()
+}
+
+func ValidSMTPServer(conn net.Conn) {
+	for {
+		command, err := bufio.NewReader(conn).ReadString('\n')
+		if err != nil {
+			return
+		}
+
+		if command == "" {
+		} else if command == "NOOP" {
+			conn.Write([]byte("250 2.0.0 Ok\n"))
+		} else if command == "STARTTLS" {
+			conn.Write([]byte("220 2.0.0 Ready to start TLS\n"))
+			// TODO: conn.Close does not actually close connection? or does client not detect it?
+			conn.Close()
+			return
+		} else if strings.HasPrefix(command, "EHLO") {
+			conn.Write([]byte("250 mock.example.com\n"))
+		}
+		conn.Write([]byte("\n"))
+	}
+}
+
+func TCPServer(l net.Listener) {
+	for {
+		conn, err := l.Accept()
+		if err != nil {
+			continue
+		}
+		defer conn.Close()
+		conn.Write([]byte("220 mock.example.com ESMTP (spam is not appreciated)\n"))
+		ValidSMTPServer(conn)
+	}
+}
+
+func TestMeasurer_run(t *testing.T) {
+	// runHelper is an helper function to run this set of tests.
+	runHelper := func(input string) (*model.Measurement, model.ExperimentMeasurer, error) {
+		m := NewExperimentMeasurer(Config{})
+		if m.ExperimentName() != "smtp" {
+			t.Fatal("invalid experiment name")
+		}
+		if m.ExperimentVersion() != "0.0.1" {
+			t.Fatal("invalid experiment version")
+		}
+		ctx := context.Background()
+		meas := &model.Measurement{
+			Input: model.MeasurementTarget(input),
+		}
+		sess := &mockable.Session{
+			MockableLogger: model.DiscardLogger,
+		}
+		callbacks := model.NewPrinterCallbacks(model.DiscardLogger)
+		err := m.Run(ctx, sess, meas, callbacks)
+		return meas, m, err
+	}
+
+	t.Run("with empty input", func(t *testing.T) {
+		_, _, err := runHelper("")
+		if !errors.Is(err, errNoInputProvided) {
+			t.Fatal("unexpected error", err)
+		}
+	})
+
+	t.Run("with invalid URL", func(t *testing.T) {
+		_, _, err := runHelper("\t")
+		if !errors.Is(err, errInputIsNotAnURL) {
+			t.Fatal("unexpected error", err)
+		}
+	})
+
+	t.Run("with invalid scheme", func(t *testing.T) {
+		_, _, err := runHelper("https://8.8.8.8:443/")
+		if !errors.Is(err, errInvalidScheme) {
+			t.Fatal("unexpected error", err)
+		}
+	})
+
+	t.Run("with broken TLS", func(t *testing.T) {
+		p := plaintextListener()
+		defer p.Close()
+
+		l := tlsListener(p)
+		defer l.Close()
+		addr := listener_addr(l)
+		go TCPServer(l)
+
+		meas, m, err := runHelper("smtps://" + addr)
+		if err != nil {
+			t.Fatal(err)
+		}
+
+		tk := meas.TestKeys.(*TestKeys)
+
+		for _, run := range tk.Runs {
+			for _, handshake := range run.TLSHandshakes {
+				if *handshake.Failure != "unknown_failure: remote error: tls: unrecognized name" {
+					t.Fatal("expected unrecognized_name in TLS handshake")
+				}
+			}
+
+			if run.NoOpCounter != 0 {
+				t.Fatalf("expected to not have any noops, not %d noops", run.NoOpCounter)
+			}
+		}
+
+		ask, err := m.GetSummaryKeys(meas)
+		if err != nil {
+			t.Fatal("cannot obtain summary")
+		}
+		summary := ask.(SummaryKeys)
+		if summary.IsAnomaly {
+			t.Fatal("expected no anomaly")
+		}
+	})
+
+	t.Run("with broken starttls", func(t *testing.T) {
+		l := plaintextListener()
+		defer l.Close()
+		addr := listener_addr(l)
+
+		go TCPServer(l)
+
+		meas, m, err := runHelper("smtp://" + addr)
+		if err != nil {
+			t.Fatal(err)
+		}
+
+		tk := meas.TestKeys.(*TestKeys)
+
+		for _, run := range tk.Runs {
+			for _, handshake := range run.TLSHandshakes {
+				if *handshake.Failure != "generic_timeout_error" {
+					t.Fatal("expected timeout in TLS handshake")
+				}
+			}
+
+			if run.NoOpCounter != 0 {
+				t.Fatalf("expected to not have any noops, not %d noops", run.NoOpCounter)
+			}
+		}
+
+		ask, err := m.GetSummaryKeys(meas)
+		if err != nil {
+			t.Fatal("cannot obtain summary")
+		}
+		summary := ask.(SummaryKeys)
+		if summary.IsAnomaly {
+			t.Fatal("expected no anomaly")
+		}
+	})
+}