From 1514e13bb86d4714550107efa58c947b1bfc39c6 Mon Sep 17 00:00:00 2001
From: zeripath <art27@cantab.net>
Date: Thu, 6 Jan 2022 00:43:45 +0000
Subject: [PATCH] Add option to convert CRLF to LF line endings for sendmail
(#18075)
It appears that several versions of sendmail require that the mail is sent to them with
LF line endings instead of CRLF endings - which of course they will then convert back
to CRLF line endings to comply with the SMTP standard.
This PR adds another setting SENDMAIL_CONVERT_CRLF which will pass the message writer
through a filter. This will filter out and convert CRLFs to LFs before writing them
out to sendmail.
Fix #18024
Signed-off-by: Andrew Thornton <art27@cantab.net>
---
custom/conf/app.example.ini | 3 +++
.../content/doc/advanced/config-cheat-sheet.en-us.md | 1 +
modules/setting/mailer.go | 12 +++++++-----
services/mailer/mailer.go | 11 +++++++++--
4 files changed, 20 insertions(+), 7 deletions(-)
diff --git a/custom/conf/app.example.ini b/custom/conf/app.example.ini
index d860923500..17343aaea1 100644
--- a/custom/conf/app.example.ini
+++ b/custom/conf/app.example.ini
@@ -1494,6 +1494,9 @@ PATH =
;;
;; Timeout for Sendmail
;SENDMAIL_TIMEOUT = 5m
+;;
+;; convert \r\n to \n for Sendmail
+;SENDMAIL_CONVERT_CRLF = true
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
diff --git a/docs/content/doc/advanced/config-cheat-sheet.en-us.md b/docs/content/doc/advanced/config-cheat-sheet.en-us.md
index 02a61fe445..247ea935ee 100644
--- a/docs/content/doc/advanced/config-cheat-sheet.en-us.md
+++ b/docs/content/doc/advanced/config-cheat-sheet.en-us.md
@@ -667,6 +667,7 @@ Define allowed algorithms and their minimum key length (use -1 to disable a type
command or full path).
- `SENDMAIL_ARGS`: **_empty_**: Specify any extra sendmail arguments.
- `SENDMAIL_TIMEOUT`: **5m**: default timeout for sending email through sendmail
+- `SENDMAIL_CONVERT_CRLF`: **true**: Most versions of sendmail prefer LF line endings rather than CRLF line endings. Set this to false if your version of sendmail requires CRLF line endings.
- `SEND_BUFFER_LEN`: **100**: Buffer length of mailing queue. **DEPRECATED** use `LENGTH` in `[queue.mailer]`
## Cache (`cache`)
diff --git a/modules/setting/mailer.go b/modules/setting/mailer.go
index 1bcd63a914..d7713f3b80 100644
--- a/modules/setting/mailer.go
+++ b/modules/setting/mailer.go
@@ -37,9 +37,10 @@ type Mailer struct {
IsTLSEnabled bool
// Sendmail sender
- SendmailPath string
- SendmailArgs []string
- SendmailTimeout time.Duration
+ SendmailPath string
+ SendmailArgs []string
+ SendmailTimeout time.Duration
+ SendmailConvertCRLF bool
}
var (
@@ -71,8 +72,9 @@ func newMailService() {
IsTLSEnabled: sec.Key("IS_TLS_ENABLED").MustBool(),
SubjectPrefix: sec.Key("SUBJECT_PREFIX").MustString(""),
- SendmailPath: sec.Key("SENDMAIL_PATH").MustString("sendmail"),
- SendmailTimeout: sec.Key("SENDMAIL_TIMEOUT").MustDuration(5 * time.Minute),
+ SendmailPath: sec.Key("SENDMAIL_PATH").MustString("sendmail"),
+ SendmailTimeout: sec.Key("SENDMAIL_TIMEOUT").MustDuration(5 * time.Minute),
+ SendmailConvertCRLF: sec.Key("SENDMAIL_CONVERT_CRLF").MustBool(true),
}
MailService.From = sec.Key("FROM").MustString(MailService.User)
MailService.EnvelopeFrom = sec.Key("ENVELOPE_FROM").MustString("")
diff --git a/services/mailer/mailer.go b/services/mailer/mailer.go
index eac2b15c3c..e5e6272f10 100644
--- a/services/mailer/mailer.go
+++ b/services/mailer/mailer.go
@@ -290,13 +290,20 @@ func (s *sendmailSender) Send(from string, to []string, msg io.WriterTo) error {
return err
}
- _, err = msg.WriteTo(pipe)
+ if setting.MailService.SendmailConvertCRLF {
+ buf := &strings.Builder{}
+ _, err = msg.WriteTo(buf)
+ if err == nil {
+ _, err = strings.NewReplacer("\r\n", "\n").WriteString(pipe, buf.String())
+ }
+ } else {
+ _, err = msg.WriteTo(pipe)
+ }
// we MUST close the pipe or sendmail will hang waiting for more of the message
// Also we should wait on our sendmail command even if something fails
closeError = pipe.Close()
waitError = cmd.Wait()
-
if err != nil {
return err
} else if closeError != nil {