Using curl to send email

Question

How can I use the curl command line program to send an email from a gmail account?

I have tried the following:

curl -n --ssl-reqd --mail-from "<sender@gmail.com>" --mail-rcpt "<receiver@server.tld>" --url smtps://smtp.gmail.com:465 -T file.txt

With file.txt being the email's contents, however, when I run this command I get the following error:

curl: (67) Access denied: 530

Is it possible to send an email from an account that is hosted by a personal server, still using curl? Does that make the authentication process easier?

Answer 1

curl --ssl-reqd \
  --url 'smtps://smtp.gmail.com:465' \
  --user 'username@gmail.com:password' \
  --mail-from 'username@gmail.com' \
  --mail-rcpt 'john@example.com' \
  --upload-file mail.txt

mail.txt file contents:

From: "User Name" <username@gmail.com>
To: "John Smith" <john@example.com>
Subject: This is a test

Hi John,
I’m sending this mail with curl thru my gmail account.
Bye!

Additional info:

1. I’m using curl version 7.21.6 with SSL support.

2. You don't need to use the --insecure switch, which prevents curl from performing SSL connection verification. See this online resource for further details.

3. It’s considered a bad security practice to pass account credentials thru command line arguments. Use --netrc-file. See the documentation.

4. You must turn on access for less secure apps or the newer App passwords.

Answer 2

if one wants to send mails as carbon copy or blind carbon copy:

curl --url 'smtps://smtp.gmail.com:465' --ssl-reqd \
  --mail-from 'username@gmail.com' --mail-rcpt 'john@example.com' \
  --mail-rcpt 'mary@gmail.com' --mail-rcpt 'eli@example.com' \
  --upload-file mail.txt --user 'username@gmail.com:password' --insecure

From: "User Name" <username@gmail.com>
To: "John Smith" <john@example.com>
Cc: "Mary Smith" <mary@example.com>
Subject: This is a test

a BCC recipient eli is not specified in the data, just in the RCPT list.

Answer 3

Crate a simple email.conf file like so

Username:   hi@example.com
Password:   OKbNGRcjiV
POP/IMAP Server:    mail.example.com

And simply run sendmail.sh, like so after making it executable (sudo chmod +x sendmail.sh)

./sendmail.sh

Code

#!/bin/bash

ARGS=$(xargs echo  $(perl -anle 's/^[^:]+//g && s/:\s+//g && print' email.conf) < /dev/null)
set -- $ARGS "$@";  

declare -A email;
email['user']=$1
email['pass']=$2
email['smtp']=$3
email['port']='587';
email['rcpt']='your-email-address@gmail.com';


email_content='From: "The title" <'"${email['user']}"'>
To: "Gmail" <'"${email['rcpt']}"'>
Subject: from '"${email['user']}"' to Gmail
Date: '"$(date)"'

Hi Gmail,
'"${email['user']}"' is sending email to you and it should work.
Regards
';


echo "$email_content" | curl -s \
    --url "smtp://${email['smtp']}:${email['port']}" \
    --user "${email['user']}:${email['pass']}" \
    --mail-from "${email['user']}" \
    --mail-rcpt "${email['rcpt']}" \
    --upload-file - # email.txt


if [[ $? == 0 ]]; then
    echo;
    echo 'okay';
else
    echo "curl error code $?";
    man curl | grep "^ \+$? \+"
fi

more

Answer 4

Mind that the form of mail.txt seems to be important / CRLF for win, LF for Linux, special characters etc.

Finally after struggling 2 hours, it works for me for GMX (they tell their SMPT port to be 587 - and further down in small letters the hint: "also 465 can be used with SSL"):

UNDER Linux (TinyCore Linux on Raspberry 3B+ with curl.tcz installed):

curl --ssl-reqd --url 'smtps://mail.gmx.net:465' --user 'mymail@gmx.at:mymailPassword' --mail-from 'mymail@gmx.at' --mail-rcpt 'mymail@gmx.at' --upload-file mail.txt

UNDER Windows:

curl --ssl-reqd --url "smtps://mail.gmx.net:465" --user "mymail@gmx.at:mymailPassword" --mail-from "mymail@gmx.at" --mail-rcpt "mymail@gmx.at" --upload-file mail_win.txt

with mail.txt:

From: "User Name" <mymail@gmx.at>
To: "John Smith" <mymail@gmx.at>
Subject: This is a test

Hi John,
Im sending this mail with curl thru my gmx account.
Bye!