Fix encoding issues

This commit is contained in:
Philipp Heckel 2021-12-28 01:26:20 +01:00
parent 7cfe909644
commit 113053a9e3
3 changed files with 213 additions and 7 deletions

View file

@ -769,7 +769,7 @@ func (s *Server) runSMTPServer() error {
s.smtpServer.Domain = s.config.SMTPServerDomain
s.smtpServer.ReadTimeout = 10 * time.Second
s.smtpServer.WriteTimeout = 10 * time.Second
s.smtpServer.MaxMessageBytes = 2 * s.config.MessageLimit
s.smtpServer.MaxMessageBytes = 1024 * 1024 // Must be much larger than message size (headers, multipart, etc.)
s.smtpServer.MaxRecipients = 1
s.smtpServer.AllowInsecureAuth = true
return s.smtpServer.ListenAndServe()

View file

@ -5,16 +5,19 @@ import (
"errors"
"github.com/emersion/go-smtp"
"io"
"mime"
"mime/multipart"
"net/mail"
"strings"
"sync"
)
var (
errInvalidDomain = errors.New("invalid domain")
errInvalidAddress = errors.New("invalid address")
errInvalidTopic = errors.New("invalid topic")
errTooManyRecipients = errors.New("too many recipients")
errInvalidDomain = errors.New("invalid domain")
errInvalidAddress = errors.New("invalid address")
errInvalidTopic = errors.New("invalid topic")
errTooManyRecipients = errors.New("too many recipients")
errUnsupportedContentType = errors.New("unsupported content type")
)
// smtpBackend implements SMTP server methods.
@ -94,6 +97,7 @@ func (s *smtpSession) Rcpt(to string) error {
func (s *smtpSession) Data(r io.Reader) error {
return s.withFailCount(func() error {
conf := s.backend.config
b, err := io.ReadAll(r) // Protected by MaxMessageBytes
if err != nil {
return err
@ -102,13 +106,21 @@ func (s *smtpSession) Data(r io.Reader) error {
if err != nil {
return err
}
body, err := io.ReadAll(io.LimitReader(msg.Body, int64(s.backend.config.MessageLimit)))
body, err := readMailBody(msg)
if err != nil {
return err
}
m := newDefaultMessage(s.topic, string(body))
if len(body) > conf.MessageLimit {
body = body[:conf.MessageLimit]
}
m := newDefaultMessage(s.topic, body)
subject := msg.Header.Get("Subject")
if subject != "" {
dec := mime.WordDecoder{}
subject, err := dec.DecodeHeader(subject)
if err != nil {
return err
}
m.Title = subject
}
if err := s.backend.sub(m); err != nil {
@ -140,3 +152,39 @@ func (s *smtpSession) withFailCount(fn func() error) error {
}
return err
}
func readMailBody(msg *mail.Message) (string, error) {
contentType, params, err := mime.ParseMediaType(msg.Header.Get("Content-Type"))
if err != nil {
return "", err
}
if contentType == "text/plain" {
body, err := io.ReadAll(msg.Body)
if err != nil {
return "", err
}
return string(body), nil
}
if strings.HasPrefix(contentType, "multipart/") {
mr := multipart.NewReader(msg.Body, params["boundary"])
for {
part, err := mr.NextPart()
if err != nil { // may be io.EOF
return "", err
}
partContentType, _, err := mime.ParseMediaType(part.Header.Get("Content-Type"))
if err != nil {
return "", err
}
if partContentType != "text/plain" {
continue
}
body, err := io.ReadAll(part)
if err != nil {
return "", err
}
return string(body), nil
}
}
return "", errUnsupportedContentType
}

158
server/smtp_server_test.go Normal file
View file

@ -0,0 +1,158 @@
package server
import (
"github.com/emersion/go-smtp"
"github.com/stretchr/testify/require"
"strings"
"testing"
)
func TestSmtpBackend_Multipart(t *testing.T) {
email := `MIME-Version: 1.0
Date: Tue, 28 Dec 2021 00:30:10 +0100
Message-ID: <CAAvm79YP0C=Rt1N=KWmSUBB87KK2rRChmdzKqF1vCwMEUiVzLQ@mail.gmail.com>
Subject: and one more
From: Phil <phil@example.com>
To: ntfy-mytopic@ntfy.sh
Content-Type: multipart/alternative; boundary="000000000000f3320b05d42915c9"
--000000000000f3320b05d42915c9
Content-Type: text/plain; charset="UTF-8"
what's up
--000000000000f3320b05d42915c9
Content-Type: text/html; charset="UTF-8"
<div dir="ltr">what&#39;s up<br clear="all"><div><br></div></div>
--000000000000f3320b05d42915c9--`
_, backend := newTestBackend(t, func(m *message) error {
require.Equal(t, "mytopic", m.Topic)
require.Equal(t, "and one more", m.Title)
require.Equal(t, "what's up\n", m.Message)
return nil
})
session, _ := backend.AnonymousLogin(nil)
require.Nil(t, session.Mail("phil@example.com", smtp.MailOptions{}))
require.Nil(t, session.Rcpt("ntfy-mytopic@ntfy.sh"))
require.Nil(t, session.Data(strings.NewReader(email)))
}
func TestSmtpBackend_Plaintext(t *testing.T) {
email := `Date: Tue, 28 Dec 2021 00:30:10 +0100
Message-ID: <CAAvm79YP0C=Rt1N=KWmSUBB87KK2rRChmdzKqF1vCwMEUiVzLQ@mail.gmail.com>
Subject: and one more
From: Phil <phil@example.com>
To: mytopic@ntfy.sh
Content-Type: text/plain; charset="UTF-8"
what's up
`
conf, backend := newTestBackend(t, func(m *message) error {
require.Equal(t, "mytopic", m.Topic)
require.Equal(t, "and one more", m.Title)
require.Equal(t, "what's up\n", m.Message)
return nil
})
conf.SMTPServerAddrPrefix = ""
session, _ := backend.AnonymousLogin(nil)
require.Nil(t, session.Mail("phil@example.com", smtp.MailOptions{}))
require.Nil(t, session.Rcpt("mytopic@ntfy.sh"))
require.Nil(t, session.Data(strings.NewReader(email)))
}
func TestSmtpBackend_Plaintext_EncodedSubject(t *testing.T) {
email := `Date: Tue, 28 Dec 2021 00:30:10 +0100
Subject: =?UTF-8?B?VGhyZWUgc2FudGFzIPCfjoXwn46F8J+OhQ==?=
From: Phil <phil@example.com>
To: ntfy-mytopic@ntfy.sh
Content-Type: text/plain; charset="UTF-8"
what's up
`
_, backend := newTestBackend(t, func(m *message) error {
require.Equal(t, "Three santas 🎅🎅🎅", m.Title)
return nil
})
session, _ := backend.AnonymousLogin(nil)
require.Nil(t, session.Mail("phil@example.com", smtp.MailOptions{}))
require.Nil(t, session.Rcpt("ntfy-mytopic@ntfy.sh"))
require.Nil(t, session.Data(strings.NewReader(email)))
}
func TestSmtpBackend_Plaintext_TooLongTruncate(t *testing.T) {
email := `Date: Tue, 28 Dec 2021 00:30:10 +0100
Message-ID: <CAAvm79YP0C=Rt1N=KWmSUBB87KK2rRChmdzKqF1vCwMEUiVzLQ@mail.gmail.com>
Subject: and one more
From: Phil <phil@example.com>
To: mytopic@ntfy.sh
Content-Type: text/plain; charset="UTF-8"
you know this is a string.
it's a long string.
it's supposed to be longer than the max message length
which is 512 bytes,
which some people say is too short
but it kinda makes sense when you look at what it looks like one a phone
heck this wasn't even half of it so far.
so i'm gonna fill the rest of this with AAAAAAAAAAAAAAAAAAAAAAAAAAA
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAa
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
and with BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB
BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB
BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB
that should do it
`
conf, backend := newTestBackend(t, func(m *message) error {
expected := `you know this is a string.
it's a long string.
it's supposed to be longer than the max message length
which is 512 bytes,
which some people say is too short
but it kinda makes sense when you look at what it looks like one a phone
heck this wasn't even half of it so far.
so i'm gonna fill the rest of this with AAAAAAAAAAAAAAAAAAAAAAAAAAA
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAa
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
and with `
require.Equal(t, expected, m.Message)
return nil
})
conf.SMTPServerAddrPrefix = ""
session, _ := backend.AnonymousLogin(nil)
require.Nil(t, session.Mail("phil@example.com", smtp.MailOptions{}))
require.Nil(t, session.Rcpt("mytopic@ntfy.sh"))
require.Nil(t, session.Data(strings.NewReader(email)))
}
func TestSmtpBackend_Unsupported(t *testing.T) {
email := `Date: Tue, 28 Dec 2021 00:30:10 +0100
Message-ID: <CAAvm79YP0C=Rt1N=KWmSUBB87KK2rRChmdzKqF1vCwMEUiVzLQ@mail.gmail.com>
Subject: and one more
From: Phil <phil@example.com>
To: mytopic@ntfy.sh
Content-Type: text/SOMETHINGELSE
what's up
`
conf, backend := newTestBackend(t, func(m *message) error {
return nil
})
conf.SMTPServerAddrPrefix = ""
session, _ := backend.Login(nil, "user", "pass")
require.Nil(t, session.Mail("phil@example.com", smtp.MailOptions{}))
require.Nil(t, session.Rcpt("mytopic@ntfy.sh"))
require.Equal(t, errUnsupportedContentType, session.Data(strings.NewReader(email)))
}
func newTestBackend(t *testing.T, sub subscriber) (*Config, *smtpBackend) {
conf := newTestConfig(t)
conf.SMTPServerListen = ":25"
conf.SMTPServerDomain = "ntfy.sh"
conf.SMTPServerAddrPrefix = "ntfy-"
backend := newMailBackend(conf, sub)
return conf, backend
}