Difference between revisions of "Msmtp"

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[[Category:Internet and Email (English)]]
+
{{Lowercase title}}
[[Category:HOWTOs (English)]] {{DISPLAYTITLE:msmtp}}
+
[[Category:Email clients]]
[http://msmtp.sourceforge.net/ msmtp] is a very simple and easy to use smtp client.
+
[[ja:Msmtp]]
 +
{{Related articles start}}
 +
{{Related|mutt}}
 +
{{Related|OfflineIMAP}}
 +
{{Related|SSMTP}}
 +
{{Related|S-nail}}
 +
{{Related|OpenSMTPD}}
 +
{{Related articles end}}
  
== Quick start ==
+
[http://msmtp.sourceforge.net/ msmtp] is a very simple and easy to use SMTP client with fairly complete [[Wikipedia:sendmail|sendmail]] compatibility.
msmtp is in the {{codeline|[extra]}} repository.
 
# pacman -S msmtp
 
  
Open up {{filename|~/.msmtprc}} in your favorite editor. The following is an example of an {{filename|.msmtprc}} for several accounts:
+
== Installing ==
<pre>
 
# A first gmail address
 
account gmail
 
host smtp.gmail.com
 
port 587
 
protocol smtp
 
auth on
 
from username@gmail.com
 
user username@gmail.com
 
password mypassword
 
tls on
 
tls_starttls on
 
tls_trust_file /usr/share/ca-certificates/mozilla/Thawte_Premium_Server_CA.crt
 
  
# A second gmail address
+
[[Install]] the {{Pkg|msmtp}} package. Additionally, [[install]] {{Pkg|msmtp-mta}}, which creates a sendmail alias to msmtp.
account gmail2 : gmail
+
 
from username2@gmail.com
+
== Basic setup ==
user username2@gmail.com
+
 
password mypassword2
+
The following is an example of a msmtp configuration (the file is based on the per-user example file located at {{ic|/usr/share/doc/msmtp/msmtprc-user.example}}; the system configuration file belongs at {{ic|/etc/msmtprc}} and its corresponding example file is located at {{ic|/usr/share/doc/msmtp/msmtprc-system.example}}):
 +
 
 +
{{hc|~/.msmtprc|
 +
# Set default values for all following accounts.
 +
defaults
 +
auth          on
 +
tls            on
 +
tls_trust_file /etc/ssl/certs/ca-certificates.crt
 +
logfile        ~/.msmtp.log
 +
 
 +
# Gmail
 +
account       gmail
 +
host          smtp.gmail.com
 +
port          587
 +
from          ''username''@gmail.com
 +
user          ''username''
 +
password      ''plain-text-password''
  
 
# A freemail service
 
# A freemail service
account freemail
+
account       freemail
host smtp.freemail.example
+
host           smtp.freemail.example
from joe_smith@freemail.example
+
from           joe_smith@freemail.example
auth on
+
...
user joe.smith
 
password secret
 
 
 
# A provider's service
 
account provider
 
host smtp.provider.example
 
  
 
# Set a default account
 
# Set a default account
 
account default : gmail
 
account default : gmail
</pre>
+
}}
  
Note: it looks like Google's in the process of becoming it's own certificate authority. For some users, they seem to have switched to a "Google Certificate Authority" certificate, which is rooted in Equifax. As such, the certificate line may have to be,
+
{{Note|If you are using SSL/TLS and receive a "Server sent empty reply" error message, see [[#Server sent empty reply]].}}
tls_trust_file /usr/share/ca-certificates/mozilla/Equifax_Secure_CA.crt
 
  
Note: if you are completely deseperate, but are 100% sure you are communicating with the right server, you can always disable the certification check :
+
The ''user'' configuration file must be explicitly readable/writeable by its owner or msmtp will fail:
tls_certcheck off
 
  
The config file needs to be read/write only to the user:
 
 
  $ chmod 600 ~/.msmtprc
 
  $ chmod 600 ~/.msmtprc
  
If you don't like to write your password into the file you may omit the "password" parameter entirely. In that case msmtp asks you for your password when sending mail. However this only works if you're using msmtp from an interactive shell like bash. If you're using mutt this (sadly) doesn't work.
+
To avoid saving the password in plain text in the configuration file, use ''passwordeval'' to launch an external program, or see the [[#Password management]] section below.  This example using Gnu PG is commonly used to perform decryption of a password:
 +
 
 +
  echo -e "password\n" | gpg --encrypt -o .msmtp-gmail.gpg # enter id (email...)
 +
 
 +
{{Warning |Most shells save command history(e.g. .bash_history .zhistory). To avoid this, use gpg with shell stdin:
 +
<code>gpg --encrypt -o .msmtp-gmail.gpg -r <email> -</code>. The ending dash is not a typo, rather it causes gpg to use stdin. After running that snippet of code, type in your password, press enter, and press Control-d so gpg can encrypt your password.}}
 +
 
 +
{{hc|~/.msmtprc|
 +
passwordeval    "gpg --quiet --for-your-eyes-only --no-tty --decrypt ~/.msmtp-gmail.gpg"
 +
}}
 +
 
 +
== Using the mail command ==
 +
 
 +
To send mails using the {{ic|mail}} command you must install the package {{Pkg|s-nail}}, which also provides the {{ic|mailx}} command. You will also need to provide a {{ic|sendmail}}-compatible MTA, either by installing {{Pkg|msmtp-mta}} (which symlinks {{ic|sendmail}} to {{ic|msmtp}}) or by editing {{ic|/etc/mail.rc}} to set the sendmail path:
 +
 
 +
{{hc|/etc/mail.rc|2=set mta=/usr/bin/msmtp}}
 +
 
 +
A {{ic|.msmtprc}} file will need to be in the home of every user who wants to send mail or alternatively the system wide {{ic|/etc/msmtprc}} can be used.
 +
 
 +
msmtp also understands aliases. Add the following line to the defaults section of msmtprc or your local configuration file:
 +
 
 +
{{hc|/etc/msmtprc|2=aliases              /etc/aliases}}
 +
 
 +
and create an aliases file in {{ic|/etc}}
 +
 
 +
{{hc|/etc/aliases|2=# Example aliases file
 +
   
 +
# Send root to Joe and Jane
 +
root: joe_smith@example.com, jane_chang@example.com
 +
 
 +
# Send everything else to admin
 +
default: admin@domain.example}}
 +
 
 +
== Test functionality ==
 +
 
 +
The account option ({{ic|1=--account=,-a}} tells which account to use as sender:
 +
 
 +
$ echo "hello there username." | msmtp -a default ''username''@domain.com
 +
 
 +
Or, with the addresses in a file:
 +
 
 +
To: ''username''@domain.com
 +
From: ''username''@gmail.com
 +
Subject: A test
 +
 +
Hello there.
 +
 
 +
$ cat test.mail | msmtp -a default <username>@domain.com
 +
 
 +
{{Tip|If using Gmail you'll need to either
 +
* If you use two factor authentication: [https://myaccount.google.com/apppasswords create an app password].
 +
* Otherwise: [https://myaccount.google.com/lesssecureapps allow less secure apps]. (not recommended)
 +
}}
 +
{{Tip|You can use ''--read-envelope-from'' instead of ''-a default'' to automatically chose account by ''From:'' field in message you are going to send.}}
 +
 
 +
== Cronie default email client ==
 +
 
 +
{{Out of date|Arch uses [[systemd/Timers]] instead of cronie}}
 +
 
 +
To make {{Pkg|cronie}} use msmtp rather than sendmail, make sure {{Pkg|msmtp-mta}} is installed, or edit the {{ic|cronie.service}} systemd unit:
 +
 
 +
{{hc|/etc/systemd/system/cronie.service.d/msmtp.conf|[Service]
 +
ExecStart&#61;
 +
ExecStart&#61;/usr/bin/crond -n -m '/usr/bin/msmtp -t'}}
 +
 
 +
Then you must tell cronie or msmtp what your email address is, either by:
  
== Issues with TLS ==
+
# Add to {{ic|/etc/msmtprc}}: {{bc|aliases /etc/aliases}} and create {{ic|/etc/aliases}}: {{bc|your_username: email@address.com}}&mdash; OR &mdash;.
If you see the following message :
+
* Add a {{ic|MAILTO}} line to the crontab: {{bc|MAILTO&#61;email@address.com}}
 +
 
 +
== Password management ==
 +
 
 +
Passwords for msmtp [http://msmtp.sourceforge.net/doc/msmtp.html#Authentication can be stored] in plaintext, encrypted files, or a keyring.
 +
 
 +
=== GNOME Keyring ===
 +
 
 +
Storing passwords in [[GNOME Keyring]] is supported natively in msmtp. Setup the keyring as described on the linked wiki page and install {{Pkg|libsecret}}. Then, store a password by running:
 +
 
 +
  secret-tool store --label=msmtp host ''smtp.your.domain'' service smtp user ''yourusername''
 +
 
 +
That's all, now msmtp should find the password automatically.
 +
 
 +
=== GnuPG ===
 +
 
 +
The {{Ic|password}} directive may be omitted. In that case, if the account in question has {{Ic|auth}} set to a legitimate value other than {{Ic|off}}, invoking msmtp from an interactive shell will ask for the password before sending mail. msmtp will not prompt if it has been called by another type of application, such as [[Mutt]]. For such cases, the {{ic|--passwordeval}} parameter
 +
can be used to call an external keyring tool like [[GnuPG]].
 +
 
 +
To do this, set up [[GnuPG]], including [[GnuPG#gpg-agent|gpg-agent]] to avoid having to enter the password every time. Then, create an encrypted password file for msmtp, as follows. Create a secure directory with {{ic|700}} permissions located on a [[tmpfs]] to avoid writing the unencrypted password to the disk. In that directory create a plain text file with the mail account password. Then, encrypt the file with your private key:
 +
 
 +
$ gpg --default-recipient-self -e ''/path/to/plain/password''
 +
 
 +
Remove the plain text file and move the encrypted file to the final location, e.g. {{ic|~/.mail/.msmtp-credentials.gpg}}. In {{ic|~/.msmtprc}} add:
 +
 
 +
{{hc|~/.msmtprc|passwordeval  "gpg --quiet --for-your-eyes-only --no-tty --decrypt ~/.mail/.msmtp-credentials.gpg"}}
 +
 
 +
Normally this is sufficient for a GUI password prompt to appear when, for example, sending a message from [[Mutt]]. If gpg prompt for the passphrase cannot be issued, then start the [[GPG#gpg-agent|gpg-agent]] before. A simple hack to start the agent is to execute a external command in your muttrc using  the backtick {{ic| ` command ` }} syntax. For example, you can put something like the following in your muttrc
 +
 
 +
{{hc|muttrc|set my_msmtp_pass&#61;`gpg -d mypwfile.gpg`}}
 +
 
 +
Mutt will execute this when it starts, gpg-agent will cache your password, msmtp will be happy and you can send mail.
 +
{{Note| If you do this, you will have to restart mutt after gpg-agent clears the password to start sending emails again}}
 +
 
 +
An alternative is to place passwords in {{ic|~/.netrc}}, a file that can act as a common pool for msmtp, [[OfflineIMAP]], and associated tools.
 +
 
 +
== Miscellaneous ==
 +
 
 +
===Using msmtp offline===
 +
 
 +
Although msmtp is great, it requires that you be online to use it. This isn't ideal for people on laptops with intermittent connections to the Internet or dialup users. Several scripts have been written to remedy this fact, collectively called msmtpqueue.
 +
 
 +
The scripts are installed under {{ic|/usr/share/doc/msmtp/msmtpqueue}}. You might want to copy the scripts to a convenient location on your computer, ({{ic|/usr/local/bin}} is a good choice).
 +
 
 +
Finally, change your MUA to use msmtp-enqueue.sh instead of msmtp when sending e-mail. By default, queued messages will be stored in {{ic|~/.msmtpqueue}}. To change this location, change the {{ic|QUEUEDIR&#61;$HOME/.msmtpqueue}} line in the scripts (or delete the line, and export the QUEUEDIR variable in {{ic|.bash_profile}} like so: {{ic|export QUEUEDIR&#61;"$XDG_DATA_HOME/msmtpqueue"}}).
 +
 
 +
When you want to send any mail that you've created and queued up run:
 +
$ /usr/local/bin/msmtp-runqueue.sh
 +
 
 +
Adding {{ic|/usr/local/bin}} to your PATH can save you some keystrokes if you're doing it manually. The README file that comes with the scripts has some handy information, reading it is recommended.
 +
 
 +
===Vim syntax highlighting===
 +
 
 +
The msmtp source distribution includes an {{ic|msmtprc}} syntax-highlighting script for [[Vim]], which is available at {{ic|/usr/share/vim/vimfiles/syntax/msmtp.vim}}. The filetype is not detected automatically. The easiest way to enable it is by adding a [http://vimdoc.sourceforge.net/htmldoc/options.html#modeline modeline] at the top or bottom of the file(s), i.e.:
 +
 
 +
    # vim:filetype=msmtp
 +
 
 +
===Send mail with PHP using msmtp===
 +
Look for ''sendmail_path'' option in your {{ic|php.ini}} and edit like this:
 +
{{bc|1=
 +
sendmail_path = "/usr/bin/msmtp -C /path/to/your/config -t"
 +
}}
 +
 
 +
Note that you '''can not''' use a user configuration file (ie: one under ~/) if you plan on using msmtp as a sendmail replacement with php or something similar.
 +
In that case just create /etc/msmtprc, and remove your user configuration (or not if you plan on using it for something else). Also make sure it's readable by whatever you're using it with (php, django, etc...)
 +
 
 +
From the msmtp manual: ''Accounts defined in the user configuration file override accounts from the system configuration file. The user configuration file must have no more permissions than user read/write''
 +
 
 +
So it's impossible to have a conf file under ~/ and have it still be readable by the php user.
 +
 
 +
To test it place this file in your php enabled server or using php-cli.
 +
{{bc|
 +
<?php
 +
mail("your@email.com", "Test email from PHP", "msmtp as sendmail for PHP");
 +
?>
 +
}}
 +
 
 +
==Troubleshooting==
 +
===Issues with TLS===
 +
If you see the following message:
 
   msmtp: TLS certificate verification failed: the certificate hasn't got a known issuer
 
   msmtp: TLS certificate verification failed: the certificate hasn't got a known issuer
 
it probably means your tls_trust_file is not right.
 
it probably means your tls_trust_file is not right.
  
Just follow the [http://msmtp.sourceforge.net/doc/msmtp.html#Transport-Layer-Security fine manual]. It explains you how to find out the server certificate issuer of a given smtp server. Then you can explore the {{filename|/usr/share/ca-certificates/}} directory to find out if by any chance, the certificate you need is there. If not, you will have to get the certificate on your own.
+
Just follow the [http://msmtp.sourceforge.net/doc/msmtp.html#Transport-Layer-Security fine manual]. It explains you how to find out the server certificate issuer of a given smtp server. Then you can explore the {{ic|/usr/share/ca-certificates/}} directory to find out if by any chance, the certificate you need is there. If not, you will have to get the certificate on your own. If you are using your own certificate, you can make msmtp trust it by adding the following to your '''~/.msmtprc''':
  
== Using msmtp offline ==
+
  tls_fingerprint <SHA1 (recommended) or MD5 fingerprint of the certificate>
Although msmtp is great, it requires that you be online to use it. This isn't ideal for people on laptops with intermittent connections to the Internet or dialup users. Several scripts have been written to remedy this fact, collectively called msmtpqueue.
+
 
 +
If you are trying to send mail through GMail and are receiving this error, have a look at [http://www.mail-archive.com/msmtp-users@lists.sourceforge.net/msg00141.html this] thread or just use the second GMail example above.
 +
 
 +
If you are completely desperate, but are 100% sure you are communicating with the right server, you can always temporarily disable the cert check:
 +
$ msmtp --tls-certcheck off
 +
 
 +
If you see the following message:
 +
  msmtp: TLS handshake failed: the operation timed out
 +
You may be affected by this [https://bugs.archlinux.org/task/44994 bug]. Recompile with "--with-ssl=openssl" (msmtp is compiled with GnuTLS by default).
 +
 
 +
===Server sent empty reply===
 +
If you get a "server sent empty reply" error, this probably means the mail server doesn't allow STARTTLS over port 587, but requires the nonstandard SSL/TLS over port 465.[https://www.fastmail.com/help/technical/ssltlsstarttls.html]
 +
 
 +
To let msmtp use SSL/TLS over port 465, add the following line to {{ic|~/.msmtprc}}:
  
The scripts can be downloaded from [http://sourceforge.net/project/showfiles.php?group_id=86651&package_id=96024 SourceForge], the most recent of which is msmtpqueue-0.5.tar.gz.
+
tls_starttls off
  
Once the scripts have been downloaded extract them using:
+
===Issues with GSSAPI===
$ tar xvzf msmtpqueue-0.5.tar.gz
 
  
After that, copy the scripts to a convenient location on your computer ({{filename|/usr/local/bin}} is a good choice):
+
If you get the following error
$ cp msmtpqueue-0.5/*.sh /usr/local/bin/
 
  
Finally, change your MUA to use msmtp-enqueue.sh instead of msmtp when sending e-mail. Queued messages will be stored in {{filename|~/.msmtpqueue}}.
+
GNU SASL: GSSAPI error in client while negotiating security context in gss_init_sec_context() in SASL library. This is most likely due insufficient credentials or malicious interactions.
  
When you want to send any mail that you've created and queued up run:
+
Try changing your auth setting to plain, instead of gssapi in your .msmtprc file [https://bbs.archlinux.org/viewtopic.php?id=138727]:
$ /usr/local/bin/msmtp-runqueue.sh
 
  
Adding {{filename|/usr/local/bin}} to your PATH can save you some keystrokes if you're doing it manually. The README file that comes with the scripts has some handy information, reading it is recommended.
+
auth plain

Latest revision as of 00:11, 30 September 2018

msmtp is a very simple and easy to use SMTP client with fairly complete sendmail compatibility.

Installing

Install the msmtp package. Additionally, install msmtp-mta, which creates a sendmail alias to msmtp.

Basic setup

The following is an example of a msmtp configuration (the file is based on the per-user example file located at /usr/share/doc/msmtp/msmtprc-user.example; the system configuration file belongs at /etc/msmtprc and its corresponding example file is located at /usr/share/doc/msmtp/msmtprc-system.example):

~/.msmtprc
# Set default values for all following accounts.
defaults
auth           on
tls            on
tls_trust_file /etc/ssl/certs/ca-certificates.crt
logfile        ~/.msmtp.log

# Gmail
account        gmail
host           smtp.gmail.com
port           587
from           username@gmail.com
user           username
password       plain-text-password

# A freemail service
account        freemail
host           smtp.freemail.example
from           joe_smith@freemail.example
...

# Set a default account
account default : gmail
Note: If you are using SSL/TLS and receive a "Server sent empty reply" error message, see #Server sent empty reply.

The user configuration file must be explicitly readable/writeable by its owner or msmtp will fail:

$ chmod 600 ~/.msmtprc

To avoid saving the password in plain text in the configuration file, use passwordeval to launch an external program, or see the #Password management section below. This example using Gnu PG is commonly used to perform decryption of a password:

 echo -e "password\n" | gpg --encrypt -o .msmtp-gmail.gpg # enter id (email...)
Warning: Most shells save command history(e.g. .bash_history .zhistory). To avoid this, use gpg with shell stdin: gpg --encrypt -o .msmtp-gmail.gpg -r <email> -. The ending dash is not a typo, rather it causes gpg to use stdin. After running that snippet of code, type in your password, press enter, and press Control-d so gpg can encrypt your password.
~/.msmtprc
passwordeval    "gpg --quiet --for-your-eyes-only --no-tty --decrypt ~/.msmtp-gmail.gpg"

Using the mail command

To send mails using the mail command you must install the package s-nail, which also provides the mailx command. You will also need to provide a sendmail-compatible MTA, either by installing msmtp-mta (which symlinks sendmail to msmtp) or by editing /etc/mail.rc to set the sendmail path:

/etc/mail.rc
set mta=/usr/bin/msmtp

A .msmtprc file will need to be in the home of every user who wants to send mail or alternatively the system wide /etc/msmtprc can be used.

msmtp also understands aliases. Add the following line to the defaults section of msmtprc or your local configuration file:

/etc/msmtprc
aliases               /etc/aliases

and create an aliases file in /etc

/etc/aliases
# Example aliases file
     
# Send root to Joe and Jane
root: joe_smith@example.com, jane_chang@example.com
   
# Send everything else to admin
default: admin@domain.example

Test functionality

The account option (--account=,-a tells which account to use as sender:

$ echo "hello there username." | msmtp -a default username@domain.com

Or, with the addresses in a file:

To: username@domain.com
From: username@gmail.com
Subject: A test

Hello there.
$ cat test.mail | msmtp -a default <username>@domain.com
Tip: If using Gmail you'll need to either
Tip: You can use --read-envelope-from instead of -a default to automatically chose account by From: field in message you are going to send.

Cronie default email client

Tango-view-refresh-red.pngThis article or section is out of date.Tango-view-refresh-red.png

Reason: Arch uses systemd/Timers instead of cronie (Discuss in Talk:Msmtp#)

To make cronie use msmtp rather than sendmail, make sure msmtp-mta is installed, or edit the cronie.service systemd unit:

/etc/systemd/system/cronie.service.d/msmtp.conf
[Service]
ExecStart=
ExecStart=/usr/bin/crond -n -m '/usr/bin/msmtp -t'

Then you must tell cronie or msmtp what your email address is, either by:

  1. Add to /etc/msmtprc:
    aliases /etc/aliases
    and create /etc/aliases:
    your_username: email@address.com
    — OR —.
  • Add a MAILTO line to the crontab:
    MAILTO=email@address.com

Password management

Passwords for msmtp can be stored in plaintext, encrypted files, or a keyring.

GNOME Keyring

Storing passwords in GNOME Keyring is supported natively in msmtp. Setup the keyring as described on the linked wiki page and install libsecret. Then, store a password by running:

 secret-tool store --label=msmtp host smtp.your.domain service smtp user yourusername

That's all, now msmtp should find the password automatically.

GnuPG

The password directive may be omitted. In that case, if the account in question has auth set to a legitimate value other than off, invoking msmtp from an interactive shell will ask for the password before sending mail. msmtp will not prompt if it has been called by another type of application, such as Mutt. For such cases, the --passwordeval parameter can be used to call an external keyring tool like GnuPG.

To do this, set up GnuPG, including gpg-agent to avoid having to enter the password every time. Then, create an encrypted password file for msmtp, as follows. Create a secure directory with 700 permissions located on a tmpfs to avoid writing the unencrypted password to the disk. In that directory create a plain text file with the mail account password. Then, encrypt the file with your private key:

$ gpg --default-recipient-self -e /path/to/plain/password

Remove the plain text file and move the encrypted file to the final location, e.g. ~/.mail/.msmtp-credentials.gpg. In ~/.msmtprc add:

~/.msmtprc
passwordeval  "gpg --quiet --for-your-eyes-only --no-tty --decrypt ~/.mail/.msmtp-credentials.gpg"

Normally this is sufficient for a GUI password prompt to appear when, for example, sending a message from Mutt. If gpg prompt for the passphrase cannot be issued, then start the gpg-agent before. A simple hack to start the agent is to execute a external command in your muttrc using the backtick ` command ` syntax. For example, you can put something like the following in your muttrc

muttrc
set my_msmtp_pass=`gpg -d mypwfile.gpg`

Mutt will execute this when it starts, gpg-agent will cache your password, msmtp will be happy and you can send mail.

Note: If you do this, you will have to restart mutt after gpg-agent clears the password to start sending emails again

An alternative is to place passwords in ~/.netrc, a file that can act as a common pool for msmtp, OfflineIMAP, and associated tools.

Miscellaneous

Using msmtp offline

Although msmtp is great, it requires that you be online to use it. This isn't ideal for people on laptops with intermittent connections to the Internet or dialup users. Several scripts have been written to remedy this fact, collectively called msmtpqueue.

The scripts are installed under /usr/share/doc/msmtp/msmtpqueue. You might want to copy the scripts to a convenient location on your computer, (/usr/local/bin is a good choice).

Finally, change your MUA to use msmtp-enqueue.sh instead of msmtp when sending e-mail. By default, queued messages will be stored in ~/.msmtpqueue. To change this location, change the QUEUEDIR=$HOME/.msmtpqueue line in the scripts (or delete the line, and export the QUEUEDIR variable in .bash_profile like so: export QUEUEDIR="$XDG_DATA_HOME/msmtpqueue").

When you want to send any mail that you've created and queued up run:

$ /usr/local/bin/msmtp-runqueue.sh

Adding /usr/local/bin to your PATH can save you some keystrokes if you're doing it manually. The README file that comes with the scripts has some handy information, reading it is recommended.

Vim syntax highlighting

The msmtp source distribution includes an msmtprc syntax-highlighting script for Vim, which is available at /usr/share/vim/vimfiles/syntax/msmtp.vim. The filetype is not detected automatically. The easiest way to enable it is by adding a modeline at the top or bottom of the file(s), i.e.:

   # vim:filetype=msmtp

Send mail with PHP using msmtp

Look for sendmail_path option in your php.ini and edit like this:

sendmail_path = "/usr/bin/msmtp -C /path/to/your/config -t"

Note that you can not use a user configuration file (ie: one under ~/) if you plan on using msmtp as a sendmail replacement with php or something similar. In that case just create /etc/msmtprc, and remove your user configuration (or not if you plan on using it for something else). Also make sure it's readable by whatever you're using it with (php, django, etc...)

From the msmtp manual: Accounts defined in the user configuration file override accounts from the system configuration file. The user configuration file must have no more permissions than user read/write

So it's impossible to have a conf file under ~/ and have it still be readable by the php user.

To test it place this file in your php enabled server or using php-cli.

<?php
mail("your@email.com", "Test email from PHP", "msmtp as sendmail for PHP");
?>

Troubleshooting

Issues with TLS

If you see the following message:

 msmtp: TLS certificate verification failed: the certificate hasn't got a known issuer

it probably means your tls_trust_file is not right.

Just follow the fine manual. It explains you how to find out the server certificate issuer of a given smtp server. Then you can explore the /usr/share/ca-certificates/ directory to find out if by any chance, the certificate you need is there. If not, you will have to get the certificate on your own. If you are using your own certificate, you can make msmtp trust it by adding the following to your ~/.msmtprc:

 tls_fingerprint <SHA1 (recommended) or MD5 fingerprint of the certificate>

If you are trying to send mail through GMail and are receiving this error, have a look at this thread or just use the second GMail example above.

If you are completely desperate, but are 100% sure you are communicating with the right server, you can always temporarily disable the cert check:

$ msmtp --tls-certcheck off

If you see the following message:

 msmtp: TLS handshake failed: the operation timed out

You may be affected by this bug. Recompile with "--with-ssl=openssl" (msmtp is compiled with GnuTLS by default).

Server sent empty reply

If you get a "server sent empty reply" error, this probably means the mail server doesn't allow STARTTLS over port 587, but requires the nonstandard SSL/TLS over port 465.[1]

To let msmtp use SSL/TLS over port 465, add the following line to ~/.msmtprc:

tls_starttls off

Issues with GSSAPI

If you get the following error

GNU SASL: GSSAPI error in client while negotiating security context in gss_init_sec_context() in SASL library.  This is most likely due insufficient credentials or malicious interactions.

Try changing your auth setting to plain, instead of gssapi in your .msmtprc file [2]:

auth plain