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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-28 13:14:23 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-28 13:14:23 +0000
commit73df946d56c74384511a194dd01dbe099584fd1a (patch)
treefd0bcea490dd81327ddfbb31e215439672c9a068 /src/net/smtp
parentInitial commit. (diff)
downloadgolang-1.16-73df946d56c74384511a194dd01dbe099584fd1a.tar.xz
golang-1.16-73df946d56c74384511a194dd01dbe099584fd1a.zip
Adding upstream version 1.16.10.upstream/1.16.10upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/net/smtp')
-rw-r--r--src/net/smtp/auth.go110
-rw-r--r--src/net/smtp/example_test.go83
-rw-r--r--src/net/smtp/smtp.go434
-rw-r--r--src/net/smtp/smtp_test.go1143
4 files changed, 1770 insertions, 0 deletions
diff --git a/src/net/smtp/auth.go b/src/net/smtp/auth.go
new file mode 100644
index 0000000..fd1a472
--- /dev/null
+++ b/src/net/smtp/auth.go
@@ -0,0 +1,110 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package smtp
+
+import (
+ "crypto/hmac"
+ "crypto/md5"
+ "errors"
+ "fmt"
+)
+
+// Auth is implemented by an SMTP authentication mechanism.
+type Auth interface {
+ // Start begins an authentication with a server.
+ // It returns the name of the authentication protocol
+ // and optionally data to include in the initial AUTH message
+ // sent to the server. It can return proto == "" to indicate
+ // that the authentication should be skipped.
+ // If it returns a non-nil error, the SMTP client aborts
+ // the authentication attempt and closes the connection.
+ Start(server *ServerInfo) (proto string, toServer []byte, err error)
+
+ // Next continues the authentication. The server has just sent
+ // the fromServer data. If more is true, the server expects a
+ // response, which Next should return as toServer; otherwise
+ // Next should return toServer == nil.
+ // If Next returns a non-nil error, the SMTP client aborts
+ // the authentication attempt and closes the connection.
+ Next(fromServer []byte, more bool) (toServer []byte, err error)
+}
+
+// ServerInfo records information about an SMTP server.
+type ServerInfo struct {
+ Name string // SMTP server name
+ TLS bool // using TLS, with valid certificate for Name
+ Auth []string // advertised authentication mechanisms
+}
+
+type plainAuth struct {
+ identity, username, password string
+ host string
+}
+
+// PlainAuth returns an Auth that implements the PLAIN authentication
+// mechanism as defined in RFC 4616. The returned Auth uses the given
+// username and password to authenticate to host and act as identity.
+// Usually identity should be the empty string, to act as username.
+//
+// PlainAuth will only send the credentials if the connection is using TLS
+// or is connected to localhost. Otherwise authentication will fail with an
+// error, without sending the credentials.
+func PlainAuth(identity, username, password, host string) Auth {
+ return &plainAuth{identity, username, password, host}
+}
+
+func isLocalhost(name string) bool {
+ return name == "localhost" || name == "127.0.0.1" || name == "::1"
+}
+
+func (a *plainAuth) Start(server *ServerInfo) (string, []byte, error) {
+ // Must have TLS, or else localhost server.
+ // Note: If TLS is not true, then we can't trust ANYTHING in ServerInfo.
+ // In particular, it doesn't matter if the server advertises PLAIN auth.
+ // That might just be the attacker saying
+ // "it's ok, you can trust me with your password."
+ if !server.TLS && !isLocalhost(server.Name) {
+ return "", nil, errors.New("unencrypted connection")
+ }
+ if server.Name != a.host {
+ return "", nil, errors.New("wrong host name")
+ }
+ resp := []byte(a.identity + "\x00" + a.username + "\x00" + a.password)
+ return "PLAIN", resp, nil
+}
+
+func (a *plainAuth) Next(fromServer []byte, more bool) ([]byte, error) {
+ if more {
+ // We've already sent everything.
+ return nil, errors.New("unexpected server challenge")
+ }
+ return nil, nil
+}
+
+type cramMD5Auth struct {
+ username, secret string
+}
+
+// CRAMMD5Auth returns an Auth that implements the CRAM-MD5 authentication
+// mechanism as defined in RFC 2195.
+// The returned Auth uses the given username and secret to authenticate
+// to the server using the challenge-response mechanism.
+func CRAMMD5Auth(username, secret string) Auth {
+ return &cramMD5Auth{username, secret}
+}
+
+func (a *cramMD5Auth) Start(server *ServerInfo) (string, []byte, error) {
+ return "CRAM-MD5", nil, nil
+}
+
+func (a *cramMD5Auth) Next(fromServer []byte, more bool) ([]byte, error) {
+ if more {
+ d := hmac.New(md5.New, []byte(a.secret))
+ d.Write(fromServer)
+ s := make([]byte, 0, d.Size())
+ return []byte(fmt.Sprintf("%s %x", a.username, d.Sum(s))), nil
+ }
+ return nil, nil
+}
diff --git a/src/net/smtp/example_test.go b/src/net/smtp/example_test.go
new file mode 100644
index 0000000..16419f4
--- /dev/null
+++ b/src/net/smtp/example_test.go
@@ -0,0 +1,83 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package smtp_test
+
+import (
+ "fmt"
+ "log"
+ "net/smtp"
+)
+
+func Example() {
+ // Connect to the remote SMTP server.
+ c, err := smtp.Dial("mail.example.com:25")
+ if err != nil {
+ log.Fatal(err)
+ }
+
+ // Set the sender and recipient first
+ if err := c.Mail("sender@example.org"); err != nil {
+ log.Fatal(err)
+ }
+ if err := c.Rcpt("recipient@example.net"); err != nil {
+ log.Fatal(err)
+ }
+
+ // Send the email body.
+ wc, err := c.Data()
+ if err != nil {
+ log.Fatal(err)
+ }
+ _, err = fmt.Fprintf(wc, "This is the email body")
+ if err != nil {
+ log.Fatal(err)
+ }
+ err = wc.Close()
+ if err != nil {
+ log.Fatal(err)
+ }
+
+ // Send the QUIT command and close the connection.
+ err = c.Quit()
+ if err != nil {
+ log.Fatal(err)
+ }
+}
+
+// variables to make ExamplePlainAuth compile, without adding
+// unnecessary noise there.
+var (
+ from = "gopher@example.net"
+ msg = []byte("dummy message")
+ recipients = []string{"foo@example.com"}
+)
+
+func ExamplePlainAuth() {
+ // hostname is used by PlainAuth to validate the TLS certificate.
+ hostname := "mail.example.com"
+ auth := smtp.PlainAuth("", "user@example.com", "password", hostname)
+
+ err := smtp.SendMail(hostname+":25", auth, from, recipients, msg)
+ if err != nil {
+ log.Fatal(err)
+ }
+}
+
+func ExampleSendMail() {
+ // Set up authentication information.
+ auth := smtp.PlainAuth("", "user@example.com", "password", "mail.example.com")
+
+ // Connect to the server, authenticate, set the sender and recipient,
+ // and send the email all in one step.
+ to := []string{"recipient@example.net"}
+ msg := []byte("To: recipient@example.net\r\n" +
+ "Subject: discount Gophers!\r\n" +
+ "\r\n" +
+ "This is the email body.\r\n")
+ err := smtp.SendMail("mail.example.com:25", auth, "sender@example.org", to, msg)
+ if err != nil {
+ log.Fatal(err)
+ }
+}
diff --git a/src/net/smtp/smtp.go b/src/net/smtp/smtp.go
new file mode 100644
index 0000000..1a6864a
--- /dev/null
+++ b/src/net/smtp/smtp.go
@@ -0,0 +1,434 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package smtp implements the Simple Mail Transfer Protocol as defined in RFC 5321.
+// It also implements the following extensions:
+// 8BITMIME RFC 1652
+// AUTH RFC 2554
+// STARTTLS RFC 3207
+// Additional extensions may be handled by clients.
+//
+// The smtp package is frozen and is not accepting new features.
+// Some external packages provide more functionality. See:
+//
+// https://godoc.org/?q=smtp
+package smtp
+
+import (
+ "crypto/tls"
+ "encoding/base64"
+ "errors"
+ "fmt"
+ "io"
+ "net"
+ "net/textproto"
+ "strings"
+)
+
+// A Client represents a client connection to an SMTP server.
+type Client struct {
+ // Text is the textproto.Conn used by the Client. It is exported to allow for
+ // clients to add extensions.
+ Text *textproto.Conn
+ // keep a reference to the connection so it can be used to create a TLS
+ // connection later
+ conn net.Conn
+ // whether the Client is using TLS
+ tls bool
+ serverName string
+ // map of supported extensions
+ ext map[string]string
+ // supported auth mechanisms
+ auth []string
+ localName string // the name to use in HELO/EHLO
+ didHello bool // whether we've said HELO/EHLO
+ helloError error // the error from the hello
+}
+
+// Dial returns a new Client connected to an SMTP server at addr.
+// The addr must include a port, as in "mail.example.com:smtp".
+func Dial(addr string) (*Client, error) {
+ conn, err := net.Dial("tcp", addr)
+ if err != nil {
+ return nil, err
+ }
+ host, _, _ := net.SplitHostPort(addr)
+ return NewClient(conn, host)
+}
+
+// NewClient returns a new Client using an existing connection and host as a
+// server name to be used when authenticating.
+func NewClient(conn net.Conn, host string) (*Client, error) {
+ text := textproto.NewConn(conn)
+ _, _, err := text.ReadResponse(220)
+ if err != nil {
+ text.Close()
+ return nil, err
+ }
+ c := &Client{Text: text, conn: conn, serverName: host, localName: "localhost"}
+ _, c.tls = conn.(*tls.Conn)
+ return c, nil
+}
+
+// Close closes the connection.
+func (c *Client) Close() error {
+ return c.Text.Close()
+}
+
+// hello runs a hello exchange if needed.
+func (c *Client) hello() error {
+ if !c.didHello {
+ c.didHello = true
+ err := c.ehlo()
+ if err != nil {
+ c.helloError = c.helo()
+ }
+ }
+ return c.helloError
+}
+
+// Hello sends a HELO or EHLO to the server as the given host name.
+// Calling this method is only necessary if the client needs control
+// over the host name used. The client will introduce itself as "localhost"
+// automatically otherwise. If Hello is called, it must be called before
+// any of the other methods.
+func (c *Client) Hello(localName string) error {
+ if err := validateLine(localName); err != nil {
+ return err
+ }
+ if c.didHello {
+ return errors.New("smtp: Hello called after other methods")
+ }
+ c.localName = localName
+ return c.hello()
+}
+
+// cmd is a convenience function that sends a command and returns the response
+func (c *Client) cmd(expectCode int, format string, args ...interface{}) (int, string, error) {
+ id, err := c.Text.Cmd(format, args...)
+ if err != nil {
+ return 0, "", err
+ }
+ c.Text.StartResponse(id)
+ defer c.Text.EndResponse(id)
+ code, msg, err := c.Text.ReadResponse(expectCode)
+ return code, msg, err
+}
+
+// helo sends the HELO greeting to the server. It should be used only when the
+// server does not support ehlo.
+func (c *Client) helo() error {
+ c.ext = nil
+ _, _, err := c.cmd(250, "HELO %s", c.localName)
+ return err
+}
+
+// ehlo sends the EHLO (extended hello) greeting to the server. It
+// should be the preferred greeting for servers that support it.
+func (c *Client) ehlo() error {
+ _, msg, err := c.cmd(250, "EHLO %s", c.localName)
+ if err != nil {
+ return err
+ }
+ ext := make(map[string]string)
+ extList := strings.Split(msg, "\n")
+ if len(extList) > 1 {
+ extList = extList[1:]
+ for _, line := range extList {
+ args := strings.SplitN(line, " ", 2)
+ if len(args) > 1 {
+ ext[args[0]] = args[1]
+ } else {
+ ext[args[0]] = ""
+ }
+ }
+ }
+ if mechs, ok := ext["AUTH"]; ok {
+ c.auth = strings.Split(mechs, " ")
+ }
+ c.ext = ext
+ return err
+}
+
+// StartTLS sends the STARTTLS command and encrypts all further communication.
+// Only servers that advertise the STARTTLS extension support this function.
+func (c *Client) StartTLS(config *tls.Config) error {
+ if err := c.hello(); err != nil {
+ return err
+ }
+ _, _, err := c.cmd(220, "STARTTLS")
+ if err != nil {
+ return err
+ }
+ c.conn = tls.Client(c.conn, config)
+ c.Text = textproto.NewConn(c.conn)
+ c.tls = true
+ return c.ehlo()
+}
+
+// TLSConnectionState returns the client's TLS connection state.
+// The return values are their zero values if StartTLS did
+// not succeed.
+func (c *Client) TLSConnectionState() (state tls.ConnectionState, ok bool) {
+ tc, ok := c.conn.(*tls.Conn)
+ if !ok {
+ return
+ }
+ return tc.ConnectionState(), true
+}
+
+// Verify checks the validity of an email address on the server.
+// If Verify returns nil, the address is valid. A non-nil return
+// does not necessarily indicate an invalid address. Many servers
+// will not verify addresses for security reasons.
+func (c *Client) Verify(addr string) error {
+ if err := validateLine(addr); err != nil {
+ return err
+ }
+ if err := c.hello(); err != nil {
+ return err
+ }
+ _, _, err := c.cmd(250, "VRFY %s", addr)
+ return err
+}
+
+// Auth authenticates a client using the provided authentication mechanism.
+// A failed authentication closes the connection.
+// Only servers that advertise the AUTH extension support this function.
+func (c *Client) Auth(a Auth) error {
+ if err := c.hello(); err != nil {
+ return err
+ }
+ encoding := base64.StdEncoding
+ mech, resp, err := a.Start(&ServerInfo{c.serverName, c.tls, c.auth})
+ if err != nil {
+ c.Quit()
+ return err
+ }
+ resp64 := make([]byte, encoding.EncodedLen(len(resp)))
+ encoding.Encode(resp64, resp)
+ code, msg64, err := c.cmd(0, strings.TrimSpace(fmt.Sprintf("AUTH %s %s", mech, resp64)))
+ for err == nil {
+ var msg []byte
+ switch code {
+ case 334:
+ msg, err = encoding.DecodeString(msg64)
+ case 235:
+ // the last message isn't base64 because it isn't a challenge
+ msg = []byte(msg64)
+ default:
+ err = &textproto.Error{Code: code, Msg: msg64}
+ }
+ if err == nil {
+ resp, err = a.Next(msg, code == 334)
+ }
+ if err != nil {
+ // abort the AUTH
+ c.cmd(501, "*")
+ c.Quit()
+ break
+ }
+ if resp == nil {
+ break
+ }
+ resp64 = make([]byte, encoding.EncodedLen(len(resp)))
+ encoding.Encode(resp64, resp)
+ code, msg64, err = c.cmd(0, string(resp64))
+ }
+ return err
+}
+
+// Mail issues a MAIL command to the server using the provided email address.
+// If the server supports the 8BITMIME extension, Mail adds the BODY=8BITMIME
+// parameter. If the server supports the SMTPUTF8 extension, Mail adds the
+// SMTPUTF8 parameter.
+// This initiates a mail transaction and is followed by one or more Rcpt calls.
+func (c *Client) Mail(from string) error {
+ if err := validateLine(from); err != nil {
+ return err
+ }
+ if err := c.hello(); err != nil {
+ return err
+ }
+ cmdStr := "MAIL FROM:<%s>"
+ if c.ext != nil {
+ if _, ok := c.ext["8BITMIME"]; ok {
+ cmdStr += " BODY=8BITMIME"
+ }
+ if _, ok := c.ext["SMTPUTF8"]; ok {
+ cmdStr += " SMTPUTF8"
+ }
+ }
+ _, _, err := c.cmd(250, cmdStr, from)
+ return err
+}
+
+// Rcpt issues a RCPT command to the server using the provided email address.
+// A call to Rcpt must be preceded by a call to Mail and may be followed by
+// a Data call or another Rcpt call.
+func (c *Client) Rcpt(to string) error {
+ if err := validateLine(to); err != nil {
+ return err
+ }
+ _, _, err := c.cmd(25, "RCPT TO:<%s>", to)
+ return err
+}
+
+type dataCloser struct {
+ c *Client
+ io.WriteCloser
+}
+
+func (d *dataCloser) Close() error {
+ d.WriteCloser.Close()
+ _, _, err := d.c.Text.ReadResponse(250)
+ return err
+}
+
+// Data issues a DATA command to the server and returns a writer that
+// can be used to write the mail headers and body. The caller should
+// close the writer before calling any more methods on c. A call to
+// Data must be preceded by one or more calls to Rcpt.
+func (c *Client) Data() (io.WriteCloser, error) {
+ _, _, err := c.cmd(354, "DATA")
+ if err != nil {
+ return nil, err
+ }
+ return &dataCloser{c, c.Text.DotWriter()}, nil
+}
+
+var testHookStartTLS func(*tls.Config) // nil, except for tests
+
+// SendMail connects to the server at addr, switches to TLS if
+// possible, authenticates with the optional mechanism a if possible,
+// and then sends an email from address from, to addresses to, with
+// message msg.
+// The addr must include a port, as in "mail.example.com:smtp".
+//
+// The addresses in the to parameter are the SMTP RCPT addresses.
+//
+// The msg parameter should be an RFC 822-style email with headers
+// first, a blank line, and then the message body. The lines of msg
+// should be CRLF terminated. The msg headers should usually include
+// fields such as "From", "To", "Subject", and "Cc". Sending "Bcc"
+// messages is accomplished by including an email address in the to
+// parameter but not including it in the msg headers.
+//
+// The SendMail function and the net/smtp package are low-level
+// mechanisms and provide no support for DKIM signing, MIME
+// attachments (see the mime/multipart package), or other mail
+// functionality. Higher-level packages exist outside of the standard
+// library.
+func SendMail(addr string, a Auth, from string, to []string, msg []byte) error {
+ if err := validateLine(from); err != nil {
+ return err
+ }
+ for _, recp := range to {
+ if err := validateLine(recp); err != nil {
+ return err
+ }
+ }
+ c, err := Dial(addr)
+ if err != nil {
+ return err
+ }
+ defer c.Close()
+ if err = c.hello(); err != nil {
+ return err
+ }
+ if ok, _ := c.Extension("STARTTLS"); ok {
+ config := &tls.Config{ServerName: c.serverName}
+ if testHookStartTLS != nil {
+ testHookStartTLS(config)
+ }
+ if err = c.StartTLS(config); err != nil {
+ return err
+ }
+ }
+ if a != nil && c.ext != nil {
+ if _, ok := c.ext["AUTH"]; !ok {
+ return errors.New("smtp: server doesn't support AUTH")
+ }
+ if err = c.Auth(a); err != nil {
+ return err
+ }
+ }
+ if err = c.Mail(from); err != nil {
+ return err
+ }
+ for _, addr := range to {
+ if err = c.Rcpt(addr); err != nil {
+ return err
+ }
+ }
+ w, err := c.Data()
+ if err != nil {
+ return err
+ }
+ _, err = w.Write(msg)
+ if err != nil {
+ return err
+ }
+ err = w.Close()
+ if err != nil {
+ return err
+ }
+ return c.Quit()
+}
+
+// Extension reports whether an extension is support by the server.
+// The extension name is case-insensitive. If the extension is supported,
+// Extension also returns a string that contains any parameters the
+// server specifies for the extension.
+func (c *Client) Extension(ext string) (bool, string) {
+ if err := c.hello(); err != nil {
+ return false, ""
+ }
+ if c.ext == nil {
+ return false, ""
+ }
+ ext = strings.ToUpper(ext)
+ param, ok := c.ext[ext]
+ return ok, param
+}
+
+// Reset sends the RSET command to the server, aborting the current mail
+// transaction.
+func (c *Client) Reset() error {
+ if err := c.hello(); err != nil {
+ return err
+ }
+ _, _, err := c.cmd(250, "RSET")
+ return err
+}
+
+// Noop sends the NOOP command to the server. It does nothing but check
+// that the connection to the server is okay.
+func (c *Client) Noop() error {
+ if err := c.hello(); err != nil {
+ return err
+ }
+ _, _, err := c.cmd(250, "NOOP")
+ return err
+}
+
+// Quit sends the QUIT command and closes the connection to the server.
+func (c *Client) Quit() error {
+ if err := c.hello(); err != nil {
+ return err
+ }
+ _, _, err := c.cmd(221, "QUIT")
+ if err != nil {
+ return err
+ }
+ return c.Text.Close()
+}
+
+// validateLine checks to see if a line has CR or LF as per RFC 5321
+func validateLine(line string) error {
+ if strings.ContainsAny(line, "\n\r") {
+ return errors.New("smtp: A line must not contain CR or LF")
+ }
+ return nil
+}
diff --git a/src/net/smtp/smtp_test.go b/src/net/smtp/smtp_test.go
new file mode 100644
index 0000000..5521937
--- /dev/null
+++ b/src/net/smtp/smtp_test.go
@@ -0,0 +1,1143 @@
+// Copyright 2010 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package smtp
+
+import (
+ "bufio"
+ "bytes"
+ "crypto/tls"
+ "crypto/x509"
+ "fmt"
+ "internal/testenv"
+ "io"
+ "net"
+ "net/textproto"
+ "runtime"
+ "strings"
+ "testing"
+ "time"
+)
+
+type authTest struct {
+ auth Auth
+ challenges []string
+ name string
+ responses []string
+}
+
+var authTests = []authTest{
+ {PlainAuth("", "user", "pass", "testserver"), []string{}, "PLAIN", []string{"\x00user\x00pass"}},
+ {PlainAuth("foo", "bar", "baz", "testserver"), []string{}, "PLAIN", []string{"foo\x00bar\x00baz"}},
+ {CRAMMD5Auth("user", "pass"), []string{"<123456.1322876914@testserver>"}, "CRAM-MD5", []string{"", "user 287eb355114cf5c471c26a875f1ca4ae"}},
+}
+
+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])
+ resp, err := test.auth.Next(challenge, true)
+ if err != nil {
+ 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)
+ }
+ }
+}
+
+// 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 bytes.Buffer
+ 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{})
+ c.Close()
+ 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(server *ServerInfo) (proto string, toServer []byte, err error) {
+ return "FOOAUTH", nil, nil
+}
+
+func (toServerEmptyAuth) Next(fromServer []byte, more 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 bytes.Buffer
+ 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)
+ }
+
+ bcmdbuf.Flush()
+ 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:<user@gmail.com> BODY=8BITMIME
+VRFY user1@gmail.com
+VRFY user2@gmail.com
+AUTH PLAIN AHVzZXIAcGFzcw==
+MAIL FROM:<user@gmail.com> BODY=8BITMIME
+RCPT TO:<golang-nuts@googlegroups.com>
+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:<user@gmail.com>
+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)
+ }
+
+ bcmdbuf.Flush()
+ 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:<user@gmail.com>
+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)
+ }
+
+ bcmdbuf.Flush()
+ 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:<user@gmail.com> 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)
+ }
+
+ bcmdbuf.Flush()
+ 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:<user+📧@gmail.com> 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)
+ }
+
+ bcmdbuf.Flush()
+ 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:<user+📧@gmail.com> 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)
+ }
+
+ bcmdbuf.Flush()
+ 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 bytes.Buffer
+ bcmdbuf := bufio.NewWriter(&cmdbuf)
+ out := func() string {
+ bcmdbuf.Flush()
+ 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 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)
+ }
+}
+
+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 bytes.Buffer
+ 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 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)
+ }
+
+ bcmdbuf.Flush()
+ 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 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 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")
+ }
+
+ 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 bytes.Buffer
+ 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 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)
+ }
+
+ bcmdbuf.Flush()
+ 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:<test@example.com>\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 bytes.Buffer
+ 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 l.Close()
+
+ // prevent data race on bcmdbuf
+ var 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 conn.Close()
+
+ tc := textproto.NewConn(conn)
+ for i := 0; i < len(data) && data[i] != ""; i++ {
+ tc.PrintfLine(data[i])
+ for len(data[i]) >= 4 && data[i][3] == '-' {
+ i++
+ tc.PrintfLine(data[i])
+ }
+ if data[i] == "221 Goodbye" {
+ return
+ }
+ read := false
+ for !read || data[i] == "354 Go ahead" {
+ msg, err := tc.ReadLine()
+ bcmdbuf.Write([]byte(msg + "\r\n"))
+ 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
+ bcmdbuf.Flush()
+ 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:<test@example.com>
+RCPT TO:<other@example.com>
+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 l.Close()
+
+ errCh := make(chan error)
+ go func() {
+ defer close(errCh)
+ conn, err := l.Accept()
+ if err != nil {
+ errCh <- fmt.Errorf("Accept: %v", err)
+ return
+ }
+ defer conn.Close()
+
+ tc := textproto.NewConn(conn)
+ tc.PrintfLine("220 hello world")
+ msg, err := tc.ReadLine()
+ if err != nil {
+ errCh <- fmt.Errorf("ReadLine error: %v", 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("PrintfLine: %v", 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 bytes.Buffer
+ 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 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")
+ }
+
+ bcmdbuf.Flush()
+ 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.GOARCH == "amd64") || runtime.GOOS == "js" {
+ testenv.SkipFlaky(t, 19229)
+ }
+ ln := newLocalListener(t)
+ defer 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 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 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 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 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)
+ 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}}
+ c = tls.Server(c, config)
+ defer c.Close()
+ return serverHandleTLS(c, t)
+ 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:<joe1@example.com>":
+ send("250 Ok")
+ case "RCPT TO:<joe2@example.com>":
+ 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-----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+-----END CERTIFICATE-----`)
+
+// localhostKey is the private key for localhostCert.
+var localhostKey = []byte(testingKey(`
+-----BEGIN RSA TESTING KEY-----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+-----END RSA TESTING KEY-----`))
+
+func testingKey(s string) string { return strings.ReplaceAll(s, "TESTING KEY", "PRIVATE KEY") }