// SPDX-FileCopyrightText: Copyright 2010 The Go Authors. All rights reserved. // SPDX-FileCopyrightText: Copyright (c) 2022-2023 The go-mail Authors // // Original net/smtp code from the Go stdlib by the Go Authors. // Use of this source code is governed by a BSD-style // LICENSE file that can be found in this directory. // // go-mail specific modifications by the go-mail Authors. // Licensed under the MIT License. // See [PROJECT ROOT]/LICENSES directory for more information. // // SPDX-License-Identifier: BSD-3-Clause AND MIT package smtp import ( "bufio" "bytes" "crypto/tls" "crypto/x509" "flag" "fmt" "io" "net" "net/textproto" "os" "runtime" "strings" "testing" "time" "github.com/wneessen/go-mail/log" ) type authTest struct { auth Auth challenges []string name string responses []string sf []bool } var authTests = []authTest{ { PlainAuth("", "user", "pass", "testserver"), []string{}, "PLAIN", []string{"\x00user\x00pass"}, []bool{false, false}, }, { PlainAuth("foo", "bar", "baz", "testserver"), []string{}, "PLAIN", []string{"foo\x00bar\x00baz"}, []bool{false, false}, }, { LoginAuth("user", "pass", "testserver"), []string{"Username:", "Password:", "User Name\x00", "Password\x00", "Invalid:"}, "LOGIN", []string{"", "user", "pass", "user", "pass", ""}, []bool{false, false, false, false, true}, }, { CRAMMD5Auth("user", "pass"), []string{"<123456.1322876914@testserver>"}, "CRAM-MD5", []string{"", "user 287eb355114cf5c471c26a875f1ca4ae"}, []bool{false, false}, }, { XOAuth2Auth("username", "token"), []string{""}, "XOAUTH2", []string{"user=username\x01auth=Bearer token\x01\x01", ""}, []bool{false}, }, } func TestAuth(t *testing.T) { testLoop: for i, test := range authTests { name, resp, err := test.auth.Start(&ServerInfo{"testserver", true, nil}) if name != test.name { t.Errorf("#%d got name %s, expected %s", i, name, test.name) } if !bytes.Equal(resp, []byte(test.responses[0])) { t.Errorf("#%d got response %s, expected %s", i, resp, test.responses[0]) } if err != nil { t.Errorf("#%d error: %s", i, err) } for j := range test.challenges { challenge := []byte(test.challenges[j]) expected := []byte(test.responses[j+1]) sf := test.sf[j] resp, err := test.auth.Next(challenge, true) if err != nil && !sf { t.Errorf("#%d error: %s", i, err) continue testLoop } if !bytes.Equal(resp, expected) { t.Errorf("#%d got %s, expected %s", i, resp, expected) continue testLoop } } } } func TestAuthPlain(t *testing.T) { tests := []struct { authName string server *ServerInfo err string }{ { authName: "servername", server: &ServerInfo{Name: "servername", TLS: true}, }, { // OK to use PlainAuth on localhost without TLS authName: "localhost", server: &ServerInfo{Name: "localhost", TLS: false}, }, { // NOT OK on non-localhost, even if server says PLAIN is OK. // (We don't know that the server is the real server.) authName: "servername", server: &ServerInfo{Name: "servername", Auth: []string{"PLAIN"}}, err: "unencrypted connection", }, { authName: "servername", server: &ServerInfo{Name: "servername", Auth: []string{"CRAM-MD5"}}, err: "unencrypted connection", }, { authName: "servername", server: &ServerInfo{Name: "attacker", TLS: true}, err: "wrong host name", }, } for i, tt := range tests { auth := PlainAuth("foo", "bar", "baz", tt.authName) _, _, err := auth.Start(tt.server) got := "" if err != nil { got = err.Error() } if got != tt.err { t.Errorf("%d. got error = %q; want %q", i, got, tt.err) } } } func TestAuthLogin(t *testing.T) { tests := []struct { authName string server *ServerInfo err string }{ { authName: "servername", server: &ServerInfo{Name: "servername", TLS: true}, }, { // OK to use LoginAuth on localhost without TLS authName: "localhost", server: &ServerInfo{Name: "localhost", TLS: false}, }, { // NOT OK on non-localhost, even if server says PLAIN is OK. // (We don't know that the server is the real server.) authName: "servername", server: &ServerInfo{Name: "servername", Auth: []string{"LOGIN"}}, err: "unencrypted connection", }, { authName: "servername", server: &ServerInfo{Name: "servername", Auth: []string{"CRAM-MD5"}}, err: "unencrypted connection", }, { authName: "servername", server: &ServerInfo{Name: "attacker", TLS: true}, err: "wrong host name", }, } for i, tt := range tests { auth := LoginAuth("foo", "bar", tt.authName) _, _, err := auth.Start(tt.server) got := "" if err != nil { got = err.Error() } if got != tt.err { t.Errorf("%d. got error = %q; want %q", i, got, tt.err) } } } func TestXOAuth2OK(t *testing.T) { server := []string{ "220 Fake server ready ESMTP", "250-fake.server", "250-AUTH XOAUTH2", "250 8BITMIME", "235 2.7.0 Accepted", } var wrote strings.Builder var fake faker fake.ReadWriter = struct { io.Reader io.Writer }{ strings.NewReader(strings.Join(server, "\r\n")), &wrote, } c, err := NewClient(fake, "fake.host") if err != nil { t.Fatalf("NewClient: %v", err) } defer c.Close() auth := XOAuth2Auth("user", "token") err = c.Auth(auth) if err != nil { t.Fatalf("XOAuth2 error: %v", err) } // the Next method returns a nil response. It must not be sent. // The client request must end with the authentication. if !strings.HasSuffix(wrote.String(), "AUTH XOAUTH2 dXNlcj11c2VyAWF1dGg9QmVhcmVyIHRva2VuAQE=\r\n") { t.Fatalf("got %q; want AUTH XOAUTH2 dXNlcj11c2VyAWF1dGg9QmVhcmVyIHRva2VuAQE=\r\n", wrote.String()) } } func TestXOAuth2Error(t *testing.T) { serverResp := []string{ "220 Fake server ready ESMTP", "250-fake.server", "250-AUTH XOAUTH2", "250 8BITMIME", "334 eyJzdGF0dXMiOiI0MDAiLCJzY2hlbWVzIjoiQmVhcmVyIiwic2NvcGUiOiJodHRwczovL21haWwuZ29vZ2xlLmNvbS8ifQ==", "535 5.7.8 Username and Password not accepted", "221 2.0.0 closing connection", } var wrote strings.Builder var fake faker fake.ReadWriter = struct { io.Reader io.Writer }{ strings.NewReader(strings.Join(serverResp, "\r\n")), &wrote, } c, err := NewClient(fake, "fake.host") if err != nil { t.Fatalf("NewClient: %v", err) } defer c.Close() auth := XOAuth2Auth("user", "token") err = c.Auth(auth) if err == nil { t.Fatal("expected auth error, got nil") } client := strings.Split(wrote.String(), "\r\n") if len(client) != 5 { t.Fatalf("unexpected number of client requests got %d; want 5", len(client)) } if client[1] != "AUTH XOAUTH2 dXNlcj11c2VyAWF1dGg9QmVhcmVyIHRva2VuAQE=" { t.Fatalf("got %q; want AUTH XOAUTH2 dXNlcj11c2VyAWF1dGg9QmVhcmVyIHRva2VuAQE=", client[1]) } // the Next method returns an empty response. It must be sent if client[2] != "" { t.Fatalf("got %q; want empty response", client[2]) } } // Issue 17794: don't send a trailing space on AUTH command when there's no password. func TestClientAuthTrimSpace(t *testing.T) { server := "220 hello world\r\n" + "200 some more" var wrote strings.Builder var fake faker fake.ReadWriter = struct { io.Reader io.Writer }{ strings.NewReader(server), &wrote, } c, err := NewClient(fake, "fake.host") if err != nil { t.Fatalf("NewClient: %v", err) } c.tls = true c.didHello = true _ = c.Auth(toServerEmptyAuth{}) if err := c.Close(); err != nil { t.Errorf("close failed: %s", err) } if got, want := wrote.String(), "AUTH FOOAUTH\r\n*\r\nQUIT\r\n"; got != want { t.Errorf("wrote %q; want %q", got, want) } } // toServerEmptyAuth is an implementation of Auth that only implements // the Start method, and returns "FOOAUTH", nil, nil. Notably, it returns // zero bytes for "toServer" so we can test that we don't send spaces at // the end of the line. See TestClientAuthTrimSpace. type toServerEmptyAuth struct{} func (toServerEmptyAuth) Start(_ *ServerInfo) (proto string, toServer []byte, err error) { return "FOOAUTH", nil, nil } func (toServerEmptyAuth) Next(_ []byte, _ bool) (toServer []byte, err error) { panic("unexpected call") } type faker struct { io.ReadWriter } func (f faker) Close() error { return nil } func (f faker) LocalAddr() net.Addr { return nil } func (f faker) RemoteAddr() net.Addr { return nil } func (f faker) SetDeadline(time.Time) error { return nil } func (f faker) SetReadDeadline(time.Time) error { return nil } func (f faker) SetWriteDeadline(time.Time) error { return nil } func TestBasic(t *testing.T) { server := strings.Join(strings.Split(basicServer, "\n"), "\r\n") client := strings.Join(strings.Split(basicClient, "\n"), "\r\n") var cmdbuf strings.Builder bcmdbuf := bufio.NewWriter(&cmdbuf) var fake faker fake.ReadWriter = bufio.NewReadWriter(bufio.NewReader(strings.NewReader(server)), bcmdbuf) c := &Client{Text: textproto.NewConn(fake), localName: "localhost"} if err := c.helo(); err != nil { t.Fatalf("HELO failed: %s", err) } if err := c.ehlo(); err == nil { t.Fatalf("Expected first EHLO to fail") } if err := c.ehlo(); err != nil { t.Fatalf("Second EHLO failed: %s", err) } c.didHello = true if ok, args := c.Extension("aUtH"); !ok || args != "LOGIN PLAIN" { t.Fatalf("Expected AUTH supported") } if ok, _ := c.Extension("DSN"); ok { t.Fatalf("Shouldn't support DSN") } if err := c.Mail("user@gmail.com"); err == nil { t.Fatalf("MAIL should require authentication") } if err := c.Verify("user1@gmail.com"); err == nil { t.Fatalf("First VRFY: expected no verification") } if err := c.Verify("user2@gmail.com>\r\nDATA\r\nAnother injected message body\r\n.\r\nQUIT\r\n"); err == nil { t.Fatalf("VRFY should have failed due to a message injection attempt") } if err := c.Verify("user2@gmail.com"); err != nil { t.Fatalf("Second VRFY: expected verification, got %s", err) } // fake TLS so authentication won't complain c.tls = true c.serverName = "smtp.google.com" if err := c.Auth(PlainAuth("", "user", "pass", "smtp.google.com")); err != nil { t.Fatalf("AUTH failed: %s", err) } if err := c.Rcpt("golang-nuts@googlegroups.com>\r\nDATA\r\nInjected message body\r\n.\r\nQUIT\r\n"); err == nil { t.Fatalf("RCPT should have failed due to a message injection attempt") } if err := c.Mail("user@gmail.com>\r\nDATA\r\nAnother injected message body\r\n.\r\nQUIT\r\n"); err == nil { t.Fatalf("MAIL should have failed due to a message injection attempt") } if err := c.Mail("user@gmail.com"); err != nil { t.Fatalf("MAIL failed: %s", err) } if err := c.Rcpt("golang-nuts@googlegroups.com"); err != nil { t.Fatalf("RCPT failed: %s", err) } msg := `From: user@gmail.com To: golang-nuts@googlegroups.com Subject: Hooray for Go Line 1 .Leading dot line . Goodbye.` w, err := c.Data() if err != nil { t.Fatalf("DATA failed: %s", err) } if _, err := w.Write([]byte(msg)); err != nil { t.Fatalf("Data write failed: %s", err) } if err := w.Close(); err != nil { t.Fatalf("Bad data response: %s", err) } if err := c.Quit(); err != nil { t.Fatalf("QUIT failed: %s", err) } if err := bcmdbuf.Flush(); err != nil { t.Errorf("flush failed: %s", err) } actualcmds := cmdbuf.String() if client != actualcmds { t.Fatalf("Got:\n%s\nExpected:\n%s", actualcmds, client) } } var basicServer = `250 mx.google.com at your service 502 Unrecognized command. 250-mx.google.com at your service 250-SIZE 35651584 250-AUTH LOGIN PLAIN 250 8BITMIME 530 Authentication required 252 Send some mail, I'll try my best 250 User is valid 235 Accepted 250 Sender OK 250 Receiver OK 354 Go ahead 250 Data OK 221 OK ` var basicClient = `HELO localhost EHLO localhost EHLO localhost MAIL FROM: BODY=8BITMIME VRFY user1@gmail.com VRFY user2@gmail.com AUTH PLAIN AHVzZXIAcGFzcw== MAIL FROM: BODY=8BITMIME RCPT TO: DATA From: user@gmail.com To: golang-nuts@googlegroups.com Subject: Hooray for Go Line 1 ..Leading dot line . Goodbye. . QUIT ` func TestExtensions(t *testing.T) { fake := func(server string) (c *Client, bcmdbuf *bufio.Writer, cmdbuf *strings.Builder) { server = strings.Join(strings.Split(server, "\n"), "\r\n") cmdbuf = &strings.Builder{} bcmdbuf = bufio.NewWriter(cmdbuf) var fake faker fake.ReadWriter = bufio.NewReadWriter(bufio.NewReader(strings.NewReader(server)), bcmdbuf) c = &Client{Text: textproto.NewConn(fake), localName: "localhost"} return c, bcmdbuf, cmdbuf } t.Run("helo", func(t *testing.T) { const ( basicServer = `250 mx.google.com at your service 250 Sender OK 221 Goodbye ` basicClient = `HELO localhost MAIL FROM: QUIT ` ) c, bcmdbuf, cmdbuf := fake(basicServer) if err := c.helo(); err != nil { t.Fatalf("HELO failed: %s", err) } c.didHello = true if err := c.Mail("user@gmail.com"); err != nil { t.Fatalf("MAIL FROM failed: %s", err) } if err := c.Quit(); err != nil { t.Fatalf("QUIT failed: %s", err) } if err := bcmdbuf.Flush(); err != nil { t.Errorf("flush failed: %s", err) } actualcmds := cmdbuf.String() client := strings.Join(strings.Split(basicClient, "\n"), "\r\n") if client != actualcmds { t.Fatalf("Got:\n%s\nExpected:\n%s", actualcmds, client) } }) t.Run("ehlo", func(t *testing.T) { const ( basicServer = `250-mx.google.com at your service 250 SIZE 35651584 250 Sender OK 221 Goodbye ` basicClient = `EHLO localhost MAIL FROM: QUIT ` ) c, bcmdbuf, cmdbuf := fake(basicServer) if err := c.Hello("localhost"); err != nil { t.Fatalf("EHLO failed: %s", err) } if ok, _ := c.Extension("8BITMIME"); ok { t.Fatalf("Shouldn't support 8BITMIME") } if ok, _ := c.Extension("SMTPUTF8"); ok { t.Fatalf("Shouldn't support SMTPUTF8") } if err := c.Mail("user@gmail.com"); err != nil { t.Fatalf("MAIL FROM failed: %s", err) } if err := c.Quit(); err != nil { t.Fatalf("QUIT failed: %s", err) } if err := bcmdbuf.Flush(); err != nil { t.Errorf("flush failed: %s", err) } actualcmds := cmdbuf.String() client := strings.Join(strings.Split(basicClient, "\n"), "\r\n") if client != actualcmds { t.Fatalf("Got:\n%s\nExpected:\n%s", actualcmds, client) } }) t.Run("ehlo 8bitmime", func(t *testing.T) { const ( basicServer = `250-mx.google.com at your service 250-SIZE 35651584 250 8BITMIME 250 Sender OK 221 Goodbye ` basicClient = `EHLO localhost MAIL FROM: BODY=8BITMIME QUIT ` ) c, bcmdbuf, cmdbuf := fake(basicServer) if err := c.Hello("localhost"); err != nil { t.Fatalf("EHLO failed: %s", err) } if ok, _ := c.Extension("8BITMIME"); !ok { t.Fatalf("Should support 8BITMIME") } if ok, _ := c.Extension("SMTPUTF8"); ok { t.Fatalf("Shouldn't support SMTPUTF8") } if err := c.Mail("user@gmail.com"); err != nil { t.Fatalf("MAIL FROM failed: %s", err) } if err := c.Quit(); err != nil { t.Fatalf("QUIT failed: %s", err) } if err := bcmdbuf.Flush(); err != nil { t.Errorf("failed to flush: %s", err) } actualcmds := cmdbuf.String() client := strings.Join(strings.Split(basicClient, "\n"), "\r\n") if client != actualcmds { t.Fatalf("Got:\n%s\nExpected:\n%s", actualcmds, client) } }) t.Run("ehlo smtputf8", func(t *testing.T) { const ( basicServer = `250-mx.google.com at your service 250-SIZE 35651584 250 SMTPUTF8 250 Sender OK 221 Goodbye ` basicClient = `EHLO localhost MAIL FROM: SMTPUTF8 QUIT ` ) c, bcmdbuf, cmdbuf := fake(basicServer) if err := c.Hello("localhost"); err != nil { t.Fatalf("EHLO failed: %s", err) } if ok, _ := c.Extension("8BITMIME"); ok { t.Fatalf("Shouldn't support 8BITMIME") } if ok, _ := c.Extension("SMTPUTF8"); !ok { t.Fatalf("Should support SMTPUTF8") } if err := c.Mail("user+📧@gmail.com"); err != nil { t.Fatalf("MAIL FROM failed: %s", err) } if err := c.Quit(); err != nil { t.Fatalf("QUIT failed: %s", err) } if err := bcmdbuf.Flush(); err != nil { t.Errorf("failed to flush: %s", err) } actualcmds := cmdbuf.String() client := strings.Join(strings.Split(basicClient, "\n"), "\r\n") if client != actualcmds { t.Fatalf("Got:\n%s\nExpected:\n%s", actualcmds, client) } }) t.Run("ehlo 8bitmime smtputf8", func(t *testing.T) { const ( basicServer = `250-mx.google.com at your service 250-SIZE 35651584 250-8BITMIME 250 SMTPUTF8 250 Sender OK 221 Goodbye ` basicClient = `EHLO localhost MAIL FROM: BODY=8BITMIME SMTPUTF8 QUIT ` ) c, bcmdbuf, cmdbuf := fake(basicServer) if err := c.Hello("localhost"); err != nil { t.Fatalf("EHLO failed: %s", err) } c.didHello = true if ok, _ := c.Extension("8BITMIME"); !ok { t.Fatalf("Should support 8BITMIME") } if ok, _ := c.Extension("SMTPUTF8"); !ok { t.Fatalf("Should support SMTPUTF8") } if err := c.Mail("user+📧@gmail.com"); err != nil { t.Fatalf("MAIL FROM failed: %s", err) } if err := c.Quit(); err != nil { t.Fatalf("QUIT failed: %s", err) } if err := bcmdbuf.Flush(); err != nil { t.Errorf("failed to flush: %s", err) } actualcmds := cmdbuf.String() client := strings.Join(strings.Split(basicClient, "\n"), "\r\n") if client != actualcmds { t.Fatalf("Got:\n%s\nExpected:\n%s", actualcmds, client) } }) } func TestNewClient(t *testing.T) { server := strings.Join(strings.Split(newClientServer, "\n"), "\r\n") client := strings.Join(strings.Split(newClientClient, "\n"), "\r\n") var cmdbuf strings.Builder bcmdbuf := bufio.NewWriter(&cmdbuf) out := func() string { if err := bcmdbuf.Flush(); err != nil { t.Errorf("failed to flush: %s", err) } return cmdbuf.String() } var fake faker fake.ReadWriter = bufio.NewReadWriter(bufio.NewReader(strings.NewReader(server)), bcmdbuf) c, err := NewClient(fake, "fake.host") if err != nil { t.Fatalf("NewClient: %v\n(after %v)", err, out()) } defer func() { _ = c.Close() }() if ok, args := c.Extension("aUtH"); !ok || args != "LOGIN PLAIN" { t.Fatalf("Expected AUTH supported") } if ok, _ := c.Extension("DSN"); ok { t.Fatalf("Shouldn't support DSN") } if err := c.Quit(); err != nil { t.Fatalf("QUIT failed: %s", err) } actualcmds := out() if client != actualcmds { t.Fatalf("Got:\n%s\nExpected:\n%s", actualcmds, client) } } // TestClient_SetDebugLog tests the Client method with the Client.SetDebugLog method // to enable debug logging func TestClient_SetDebugLog(t *testing.T) { server := strings.Join(strings.Split(newClientServer, "\n"), "\r\n") var cmdbuf strings.Builder bcmdbuf := bufio.NewWriter(&cmdbuf) out := func() string { if err := bcmdbuf.Flush(); err != nil { t.Errorf("failed to flush: %s", err) } return cmdbuf.String() } var fake faker fake.ReadWriter = bufio.NewReadWriter(bufio.NewReader(strings.NewReader(server)), bcmdbuf) c, err := NewClient(fake, "fake.host") if err != nil { t.Fatalf("NewClient: %v\n(after %v)", err, out()) } defer func() { _ = c.Close() }() c.SetDebugLog(true) if !c.debug { t.Errorf("Expected DebugLog flag to be true but received false") } } // TestClient_SetLogger tests the Client method with the Client.SetLogger method // to provide a custom logger func TestClient_SetLogger(t *testing.T) { server := strings.Join(strings.Split(newClientServer, "\n"), "\r\n") var cmdbuf strings.Builder bcmdbuf := bufio.NewWriter(&cmdbuf) out := func() string { if err := bcmdbuf.Flush(); err != nil { t.Errorf("failed to flush: %s", err) } return cmdbuf.String() } var fake faker fake.ReadWriter = bufio.NewReadWriter(bufio.NewReader(strings.NewReader(server)), bcmdbuf) c, err := NewClient(fake, "fake.host") if err != nil { t.Fatalf("NewClient: %v\n(after %v)", err, out()) } defer func() { _ = c.Close() }() c.SetLogger(log.New(os.Stderr, log.LevelDebug)) if c.logger == nil { t.Errorf("Expected Logger to be set but received nil") } c.logger.Debugf(log.Log{Direction: log.DirServerToClient, Format: "%s", Messages: []interface{}{"test"}}) c.SetLogger(nil) c.logger.Debugf(log.Log{Direction: log.DirServerToClient, Format: "%s", Messages: []interface{}{"test"}}) } var newClientServer = `220 hello world 250-mx.google.com at your service 250-SIZE 35651584 250-AUTH LOGIN PLAIN 250 8BITMIME 221 OK ` var newClientClient = `EHLO localhost QUIT ` func TestNewClient2(t *testing.T) { server := strings.Join(strings.Split(newClient2Server, "\n"), "\r\n") client := strings.Join(strings.Split(newClient2Client, "\n"), "\r\n") var cmdbuf strings.Builder bcmdbuf := bufio.NewWriter(&cmdbuf) var fake faker fake.ReadWriter = bufio.NewReadWriter(bufio.NewReader(strings.NewReader(server)), bcmdbuf) c, err := NewClient(fake, "fake.host") if err != nil { t.Fatalf("NewClient: %v", err) } defer func() { _ = c.Close() }() if ok, _ := c.Extension("DSN"); ok { t.Fatalf("Shouldn't support DSN") } if err := c.Quit(); err != nil { t.Fatalf("QUIT failed: %s", err) } if err := bcmdbuf.Flush(); err != nil { t.Errorf("flush failed: %s", err) } actualcmds := cmdbuf.String() if client != actualcmds { t.Fatalf("Got:\n%s\nExpected:\n%s", actualcmds, client) } } var newClient2Server = `220 hello world 502 EH? 250-mx.google.com at your service 250-SIZE 35651584 250-AUTH LOGIN PLAIN 250 8BITMIME 221 OK ` var newClient2Client = `EHLO localhost HELO localhost QUIT ` func TestNewClientWithTLS(t *testing.T) { cert, err := tls.X509KeyPair(localhostCert, localhostKey) if err != nil { t.Fatalf("loadcert: %v", err) } config := tls.Config{Certificates: []tls.Certificate{cert}} ln, err := tls.Listen("tcp", "127.0.0.1:0", &config) if err != nil { ln, err = tls.Listen("tcp", "[::1]:0", &config) if err != nil { t.Fatalf("server: listen: %v", err) } } go func() { conn, err := ln.Accept() if err != nil { t.Errorf("server: accept: %v", err) return } defer func() { _ = conn.Close() }() _, err = conn.Write([]byte("220 SIGNS\r\n")) if err != nil { t.Errorf("server: write: %v", err) return } }() config.InsecureSkipVerify = true conn, err := tls.Dial("tcp", ln.Addr().String(), &config) if err != nil { t.Fatalf("client: dial: %v", err) } defer func() { _ = conn.Close() }() client, err := NewClient(conn, ln.Addr().String()) if err != nil { t.Fatalf("smtp: newclient: %v", err) } if !client.tls { t.Errorf("client.tls Got: %t Expected: %t", client.tls, true) } } func TestHello(t *testing.T) { if len(helloServer) != len(helloClient) { t.Fatalf("Hello server and client size mismatch") } tf := func(fake faker, i int) error { c, err := NewClient(fake, "fake.host") if err != nil { t.Fatalf("NewClient: %v", err) } defer func() { _ = c.Close() }() c.localName = "customhost" err = nil switch i { case 0: err = c.Hello("hostinjection>\n\rDATA\r\nInjected message body\r\n.\r\nQUIT\r\n") if err == nil { t.Errorf("Expected Hello to be rejected due to a message injection attempt") } err = c.Hello("customhost") case 1: err = c.StartTLS(nil) if err.Error() == "502 Not implemented" { err = nil } case 2: err = c.Verify("test@example.com") case 3: c.tls = true c.serverName = "smtp.google.com" err = c.Auth(PlainAuth("", "user", "pass", "smtp.google.com")) case 4: err = c.Mail("test@example.com") case 5: ok, _ := c.Extension("feature") if ok { t.Errorf("Expected FEATURE not to be supported") } case 6: err = c.Reset() case 7: err = c.Quit() case 8: err = c.Verify("test@example.com") if err != nil { err = c.Hello("customhost") if err != nil { t.Errorf("Want error, got none") } } case 9: err = c.Noop() default: t.Fatalf("Unhandled command") } if err != nil { t.Errorf("Command %d failed: %v", i, err) } return nil } for i := 0; i < len(helloServer); i++ { server := strings.Join(strings.Split(baseHelloServer+helloServer[i], "\n"), "\r\n") client := strings.Join(strings.Split(baseHelloClient+helloClient[i], "\n"), "\r\n") var cmdbuf strings.Builder bcmdbuf := bufio.NewWriter(&cmdbuf) var fake faker fake.ReadWriter = bufio.NewReadWriter(bufio.NewReader(strings.NewReader(server)), bcmdbuf) if err := tf(fake, i); err != nil { t.Error(err) } if err := bcmdbuf.Flush(); err != nil { t.Errorf("flush failed: %s", err) } actualcmds := cmdbuf.String() if client != actualcmds { t.Errorf("Got:\n%s\nExpected:\n%s", actualcmds, client) } } } var baseHelloServer = `220 hello world 502 EH? 250-mx.google.com at your service 250 FEATURE ` var helloServer = []string{ "", "502 Not implemented\n", "250 User is valid\n", "235 Accepted\n", "250 Sender ok\n", "", "250 Reset ok\n", "221 Goodbye\n", "250 Sender ok\n", "250 ok\n", } var baseHelloClient = `EHLO customhost HELO customhost ` var helloClient = []string{ "", "STARTTLS\n", "VRFY test@example.com\n", "AUTH PLAIN AHVzZXIAcGFzcw==\n", "MAIL FROM:\n", "", "RSET\n", "QUIT\n", "VRFY test@example.com\n", "NOOP\n", } func TestSendMail(t *testing.T) { server := strings.Join(strings.Split(sendMailServer, "\n"), "\r\n") client := strings.Join(strings.Split(sendMailClient, "\n"), "\r\n") var cmdbuf strings.Builder bcmdbuf := bufio.NewWriter(&cmdbuf) l, err := net.Listen("tcp", "127.0.0.1:0") if err != nil { t.Fatalf("Unable to create listener: %v", err) } defer func() { _ = l.Close() }() // prevent data race on bcmdbuf done := make(chan struct{}) go func(data []string) { defer close(done) conn, err := l.Accept() if err != nil { t.Errorf("Accept error: %v", err) return } defer func() { _ = conn.Close() }() tc := textproto.NewConn(conn) for i := 0; i < len(data) && data[i] != ""; i++ { if err := tc.PrintfLine(data[i]); err != nil { t.Errorf("printing to textproto failed: %s", err) } for len(data[i]) >= 4 && data[i][3] == '-' { i++ if err := tc.PrintfLine(data[i]); err != nil { t.Errorf("printing to textproto failed: %s", err) } } if data[i] == "221 Goodbye" { return } read := false for !read || data[i] == "354 Go ahead" { msg, err := tc.ReadLine() if _, err := bcmdbuf.Write([]byte(msg + "\r\n")); err != nil { t.Errorf("write failed: %s", err) } read = true if err != nil { t.Errorf("Read error: %v", err) return } if data[i] == "354 Go ahead" && msg == "." { break } } } }(strings.Split(server, "\r\n")) err = SendMail(l.Addr().String(), nil, "test@example.com", []string{"other@example.com>\n\rDATA\r\nInjected message body\r\n.\r\nQUIT\r\n"}, []byte(strings.Replace(`From: test@example.com To: other@example.com Subject: SendMail test SendMail is working for me. `, "\n", "\r\n", -1))) if err == nil { t.Errorf("Expected SendMail to be rejected due to a message injection attempt") } err = SendMail(l.Addr().String(), nil, "test@example.com", []string{"other@example.com"}, []byte(strings.Replace(`From: test@example.com To: other@example.com Subject: SendMail test SendMail is working for me. `, "\n", "\r\n", -1))) if err != nil { t.Errorf("%v", err) } <-done if err := bcmdbuf.Flush(); err != nil { t.Errorf("flush failed: %s", err) } actualcmds := cmdbuf.String() if client != actualcmds { t.Errorf("Got:\n%s\nExpected:\n%s", actualcmds, client) } } var sendMailServer = `220 hello world 502 EH? 250 mx.google.com at your service 250 Sender ok 250 Receiver ok 354 Go ahead 250 Data ok 221 Goodbye ` var sendMailClient = `EHLO localhost HELO localhost MAIL FROM: RCPT TO: DATA From: test@example.com To: other@example.com Subject: SendMail test SendMail is working for me. . QUIT ` func TestSendMailWithAuth(t *testing.T) { l, err := net.Listen("tcp", "127.0.0.1:0") if err != nil { t.Fatalf("Unable to create listener: %v", err) } defer func() { _ = l.Close() }() errCh := make(chan error) go func() { defer close(errCh) conn, err := l.Accept() if err != nil { errCh <- fmt.Errorf("listener Accept: %w", err) return } defer func() { _ = conn.Close() }() tc := textproto.NewConn(conn) if err := tc.PrintfLine("220 hello world"); err != nil { t.Errorf("textproto connetion print failed: %s", err) } msg, err := tc.ReadLine() if err != nil { errCh <- fmt.Errorf("textproto connection ReadLine error: %w", err) return } const wantMsg = "EHLO localhost" if msg != wantMsg { errCh <- fmt.Errorf("unexpected response %q; want %q", msg, wantMsg) return } err = tc.PrintfLine("250 mx.google.com at your service") if err != nil { errCh <- fmt.Errorf("textproto connection PrintfLine: %w", err) return } }() err = SendMail(l.Addr().String(), PlainAuth("", "user", "pass", "smtp.google.com"), "test@example.com", []string{"other@example.com"}, []byte(strings.Replace(`From: test@example.com To: other@example.com Subject: SendMail test SendMail is working for me. `, "\n", "\r\n", -1))) if err == nil { t.Error("SendMail: Server doesn't support AUTH, expected to get an error, but got none ") } if err.Error() != "smtp: server doesn't support AUTH" { t.Errorf("Expected: smtp: server doesn't support AUTH, got: %s", err) } err = <-errCh if err != nil { t.Fatalf("server error: %v", err) } } func TestAuthFailed(t *testing.T) { server := strings.Join(strings.Split(authFailedServer, "\n"), "\r\n") client := strings.Join(strings.Split(authFailedClient, "\n"), "\r\n") var cmdbuf strings.Builder bcmdbuf := bufio.NewWriter(&cmdbuf) var fake faker fake.ReadWriter = bufio.NewReadWriter(bufio.NewReader(strings.NewReader(server)), bcmdbuf) c, err := NewClient(fake, "fake.host") if err != nil { t.Fatalf("NewClient: %v", err) } defer func() { _ = c.Close() }() c.tls = true c.serverName = "smtp.google.com" err = c.Auth(PlainAuth("", "user", "pass", "smtp.google.com")) if err == nil { t.Error("Auth: expected error; got none") } else if err.Error() != "535 Invalid credentials\nplease see www.example.com" { t.Errorf("Auth: got error: %v, want: %s", err, "535 Invalid credentials\nplease see www.example.com") } if err := bcmdbuf.Flush(); err != nil { t.Errorf("flush failed: %s", err) } actualcmds := cmdbuf.String() if client != actualcmds { t.Errorf("Got:\n%s\nExpected:\n%s", actualcmds, client) } } var authFailedServer = `220 hello world 250-mx.google.com at your service 250 AUTH LOGIN PLAIN 535-Invalid credentials 535 please see www.example.com 221 Goodbye ` var authFailedClient = `EHLO localhost AUTH PLAIN AHVzZXIAcGFzcw== * QUIT ` func TestTLSClient(t *testing.T) { if runtime.GOOS == "freebsd" || runtime.GOOS == "js" || runtime.GOOS == "wasip1" { SkipFlaky(t, 19229) } ln := newLocalListener(t) defer func() { _ = ln.Close() }() errc := make(chan error) go func() { errc <- sendMail(ln.Addr().String()) }() conn, err := ln.Accept() if err != nil { t.Fatalf("failed to accept connection: %v", err) } defer func() { _ = conn.Close() }() if err := serverHandle(conn, t); err != nil { t.Fatalf("failed to handle connection: %v", err) } if err := <-errc; err != nil { t.Fatalf("client error: %v", err) } } func TestTLSConnState(t *testing.T) { ln := newLocalListener(t) defer func() { _ = ln.Close() }() clientDone := make(chan bool) serverDone := make(chan bool) go func() { defer close(serverDone) c, err := ln.Accept() if err != nil { t.Errorf("Server accept: %v", err) return } defer func() { _ = c.Close() }() if err := serverHandle(c, t); err != nil { t.Errorf("server error: %v", err) } }() go func() { defer close(clientDone) c, err := Dial(ln.Addr().String()) if err != nil { t.Errorf("Client dial: %v", err) return } defer func() { _ = c.Quit() }() cfg := &tls.Config{ServerName: "example.com"} testHookStartTLS(cfg) // set the RootCAs if err := c.StartTLS(cfg); err != nil { t.Errorf("StartTLS: %v", err) return } cs, ok := c.TLSConnectionState() if !ok { t.Errorf("TLSConnectionState returned ok == false; want true") return } if cs.Version == 0 || !cs.HandshakeComplete { t.Errorf("ConnectionState = %#v; expect non-zero Version and HandshakeComplete", cs) } }() <-clientDone <-serverDone } func newLocalListener(t *testing.T) net.Listener { ln, err := net.Listen("tcp", "127.0.0.1:0") if err != nil { ln, err = net.Listen("tcp6", "[::1]:0") } if err != nil { t.Fatal(err) } return ln } type smtpSender struct { w io.Writer } func (s smtpSender) send(f string) { _, _ = s.w.Write([]byte(f + "\r\n")) } // smtp server, finely tailored to deal with our own client only! func serverHandle(c net.Conn, t *testing.T) error { send := smtpSender{c}.send send("220 127.0.0.1 ESMTP service ready") s := bufio.NewScanner(c) tf := func(config *tls.Config) error { c = tls.Server(c, config) defer func() { _ = c.Close() }() return serverHandleTLS(c, t) } for s.Scan() { switch s.Text() { case "EHLO localhost": send("250-127.0.0.1 ESMTP offers a warm hug of welcome") send("250-STARTTLS") send("250 Ok") case "STARTTLS": send("220 Go ahead") keypair, err := tls.X509KeyPair(localhostCert, localhostKey) if err != nil { return err } config := &tls.Config{Certificates: []tls.Certificate{keypair}} return tf(config) default: t.Fatalf("unrecognized command: %q", s.Text()) } } return s.Err() } func serverHandleTLS(c net.Conn, t *testing.T) error { send := smtpSender{c}.send s := bufio.NewScanner(c) for s.Scan() { switch s.Text() { case "EHLO localhost": send("250 Ok") case "MAIL FROM:": send("250 Ok") case "RCPT TO:": send("250 Ok") case "DATA": send("354 send the mail data, end with .") send("250 Ok") case "Subject: test": case "": case "howdy!": case ".": case "QUIT": send("221 127.0.0.1 Service closing transmission channel") return nil default: t.Fatalf("unrecognized command during TLS: %q", s.Text()) } } return s.Err() } func init() { testRootCAs := x509.NewCertPool() testRootCAs.AppendCertsFromPEM(localhostCert) testHookStartTLS = func(config *tls.Config) { config.RootCAs = testRootCAs } } func sendMail(hostPort string) error { from := "joe1@example.com" to := []string{"joe2@example.com"} return SendMail(hostPort, nil, from, to, []byte("Subject: test\n\nhowdy!")) } // localhostCert is a PEM-encoded TLS cert generated from src/crypto/tls: // // go run generate_cert.go --rsa-bits 1024 --host 127.0.0.1,::1,example.com \ // --ca --start-date "Jan 1 00:00:00 1970" --duration=1000000h var localhostCert = []byte(` -----BEGIN CERTIFICATE----- MIICFDCCAX2gAwIBAgIRAK0xjnaPuNDSreeXb+z+0u4wDQYJKoZIhvcNAQELBQAw EjEQMA4GA1UEChMHQWNtZSBDbzAgFw03MDAxMDEwMDAwMDBaGA8yMDg0MDEyOTE2 MDAwMFowEjEQMA4GA1UEChMHQWNtZSBDbzCBnzANBgkqhkiG9w0BAQEFAAOBjQAw gYkCgYEA0nFbQQuOWsjbGtejcpWz153OlziZM4bVjJ9jYruNw5n2Ry6uYQAffhqa JOInCmmcVe2siJglsyH9aRh6vKiobBbIUXXUU1ABd56ebAzlt0LobLlx7pZEMy30 LqIi9E6zmL3YvdGzpYlkFRnRrqwEtWYbGBf3znO250S56CCWH2UCAwEAAaNoMGYw DgYDVR0PAQH/BAQDAgKkMBMGA1UdJQQMMAoGCCsGAQUFBwMBMA8GA1UdEwEB/wQF MAMBAf8wLgYDVR0RBCcwJYILZXhhbXBsZS5jb22HBH8AAAGHEAAAAAAAAAAAAAAA AAAAAAEwDQYJKoZIhvcNAQELBQADgYEAbZtDS2dVuBYvb+MnolWnCNqvw1w5Gtgi NmvQQPOMgM3m+oQSCPRTNGSg25e1Qbo7bgQDv8ZTnq8FgOJ/rbkyERw2JckkHpD4 n4qcK27WkEDBtQFlPihIM8hLIuzWoi/9wygiElTy/tVL3y7fGCvY2/k1KBthtZGF tN8URjVmyEo= -----END CERTIFICATE-----`) // localhostKey is the private key for localhostCert. var localhostKey = []byte(testingKey(` -----BEGIN RSA TESTING KEY----- MIICXgIBAAKBgQDScVtBC45ayNsa16NylbPXnc6XOJkzhtWMn2Niu43DmfZHLq5h AB9+Gpok4icKaZxV7ayImCWzIf1pGHq8qKhsFshRddRTUAF3np5sDOW3QuhsuXHu lkQzLfQuoiL0TrOYvdi90bOliWQVGdGurAS1ZhsYF/fOc7bnRLnoIJYfZQIDAQAB AoGBAMst7OgpKyFV6c3JwyI/jWqxDySL3caU+RuTTBaodKAUx2ZEmNJIlx9eudLA kucHvoxsM/eRxlxkhdFxdBcwU6J+zqooTnhu/FE3jhrT1lPrbhfGhyKnUrB0KKMM VY3IQZyiehpxaeXAwoAou6TbWoTpl9t8ImAqAMY8hlULCUqlAkEA+9+Ry5FSYK/m 542LujIcCaIGoG1/Te6Sxr3hsPagKC2rH20rDLqXwEedSFOpSS0vpzlPAzy/6Rbb PHTJUhNdwwJBANXkA+TkMdbJI5do9/mn//U0LfrCR9NkcoYohxfKz8JuhgRQxzF2 6jpo3q7CdTuuRixLWVfeJzcrAyNrVcBq87cCQFkTCtOMNC7fZnCTPUv+9q1tcJyB vNjJu3yvoEZeIeuzouX9TJE21/33FaeDdsXbRhQEj23cqR38qFHsF1qAYNMCQQDP QXLEiJoClkR2orAmqjPLVhR3t2oB3INcnEjLNSq8LHyQEfXyaFfu4U9l5+fRPL2i jiC0k/9L5dHUsF0XZothAkEA23ddgRs+Id/HxtojqqUT27B8MT/IGNrYsp4DvS/c qgkeluku4GjxRlDMBuXk94xOBEinUs+p/hwP1Alll80Tpg== -----END RSA TESTING KEY-----`)) func testingKey(s string) string { return strings.ReplaceAll(s, "TESTING KEY", "PRIVATE KEY") } var flaky = flag.Bool("flaky", false, "run known-flaky tests too") func SkipFlaky(t testing.TB, issue int) { t.Helper() if !*flaky { t.Skipf("skipping known flaky test without the -flaky flag; see golang.org/issue/%d", issue) } }