How to block sending mails?

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I want to block specific user from sending emails. I tried doing these things which did not help:



  1. Commented user in /etc/passwd

  2. Wrote passwd -l user and restarted sendmail service.

User can't receive mails - that's OK, but they still may send mails. I use Sendmail (port 25) and Dovecot (port 110 POP3).



Any ideas to block a user from sending mails?






sendmail







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  • 1




    The purported duplicate question is about a Posfix system. This question is about, as it says, a Sendmail system. It is not the same answer for both.
    – JdeBP
    Aug 8 at 10:09










  • Then it is not dupe.
    – peterh
    Aug 8 at 19:55














up vote
1
down vote

favorite












I want to block specific user from sending emails. I tried doing these things which did not help:



  1. Commented user in /etc/passwd

  2. Wrote passwd -l user and restarted sendmail service.

User can't receive mails - that's OK, but they still may send mails. I use Sendmail (port 25) and Dovecot (port 110 POP3).



Any ideas to block a user from sending mails?






sendmail







share|improve this question



















  • 1




    The purported duplicate question is about a Posfix system. This question is about, as it says, a Sendmail system. It is not the same answer for both.
    – JdeBP
    Aug 8 at 10:09










  • Then it is not dupe.
    – peterh
    Aug 8 at 19:55












up vote
1
down vote

favorite









up vote
1
down vote

favorite











I want to block specific user from sending emails. I tried doing these things which did not help:



  1. Commented user in /etc/passwd

  2. Wrote passwd -l user and restarted sendmail service.

User can't receive mails - that's OK, but they still may send mails. I use Sendmail (port 25) and Dovecot (port 110 POP3).



Any ideas to block a user from sending mails?






sendmail







share|improve this question















I want to block specific user from sending emails. I tried doing these things which did not help:



  1. Commented user in /etc/passwd

  2. Wrote passwd -l user and restarted sendmail service.

User can't receive mails - that's OK, but they still may send mails. I use Sendmail (port 25) and Dovecot (port 110 POP3).



Any ideas to block a user from sending mails?






sendmail




sendmail






share|improve this question















share|improve this question













share|improve this question




share|improve this question








edited Aug 8 at 10:05









slm♦

238k65491662




238k65491662










asked Aug 8 at 9:39









it dev

244




244







  • 1




    The purported duplicate question is about a Posfix system. This question is about, as it says, a Sendmail system. It is not the same answer for both.
    – JdeBP
    Aug 8 at 10:09










  • Then it is not dupe.
    – peterh
    Aug 8 at 19:55












  • 1




    The purported duplicate question is about a Posfix system. This question is about, as it says, a Sendmail system. It is not the same answer for both.
    – JdeBP
    Aug 8 at 10:09










  • Then it is not dupe.
    – peterh
    Aug 8 at 19:55







1




1




The purported duplicate question is about a Posfix system. This question is about, as it says, a Sendmail system. It is not the same answer for both.
– JdeBP
Aug 8 at 10:09




The purported duplicate question is about a Posfix system. This question is about, as it says, a Sendmail system. It is not the same answer for both.
– JdeBP
Aug 8 at 10:09












Then it is not dupe.
– peterh
Aug 8 at 19:55




Then it is not dupe.
– peterh
Aug 8 at 19:55










1 Answer
1






active

oldest

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up vote
1
down vote













In Sendmail you can add this user to the /etc/mail/access database file (access.db) to disallow them from sending emails:



Put their address in the file /etc/mail/access:



user@my-domain.com REJECT


Then rebuild it:



$ makemap hash /etc/mail/access.db < /etc/mail/access


NOTE: From what I remember you may have to put several permutations of their email address in this file to stop them. so things like user@localhost, etc.



I do not have a sendmail setup handy, but you can typically use a Makefile command that's provided in newer implementations of sendmail.



For more controlling the sending/receiving via Sendmail you can do more specific controls like this in this file:



To:a1@server.vikas.com REJECT # Reject a1 user from recieving mails
From:a1@server.vikas.com REJECT # Reject a1 user from sending mails


References



  • How to enable/disable user's access to email (sendmail)





share|improve this answer




















  • Is it necessary to rebuild it? I am a little frightened to use makemap command
    – it dev
    Aug 8 at 10:22










  • I seem to remember that restarting the sendmail service did this as well. But yeah you typically have to rebuild these files in order for sendmail to use them. BTW I just reinstalled sendmail on CentOS 7 and it does still come with a make command, so you should be able to run that if your setup has it. If you're pensive to do this, back up the whole /etc/mail dir 1st.
    – slm♦
    Aug 8 at 10:23







  • 1




    Good old sendmail...I prefered to deal with it editing .mc files...it would be interesting understanding the problem of the user, blocking users in sendmail wont prevent users/malware scripts form sending email/spam via TCP/25 if the infra-structure allows it.
    – Rui F Ribeiro
    Aug 8 at 10:48










  • @slm, may I only restart sendmail service after REJECTING user in access file? Will it help?
    – it dev
    Aug 8 at 11:13










  • @itdev - my suggestion was to try doing a restart after adding REJECT entry to see if it triggers a rebuild of access.db, but I'm 90% sure that you have to rebuild these manually using either rehash or the make command.
    – slm♦
    Aug 8 at 11:15










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1 Answer
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active

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active

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up vote
1
down vote













In Sendmail you can add this user to the /etc/mail/access database file (access.db) to disallow them from sending emails:



Put their address in the file /etc/mail/access:



user@my-domain.com REJECT


Then rebuild it:



$ makemap hash /etc/mail/access.db < /etc/mail/access


NOTE: From what I remember you may have to put several permutations of their email address in this file to stop them. so things like user@localhost, etc.



I do not have a sendmail setup handy, but you can typically use a Makefile command that's provided in newer implementations of sendmail.



For more controlling the sending/receiving via Sendmail you can do more specific controls like this in this file:



To:a1@server.vikas.com REJECT # Reject a1 user from recieving mails
From:a1@server.vikas.com REJECT # Reject a1 user from sending mails


References



  • How to enable/disable user's access to email (sendmail)





share|improve this answer




















  • Is it necessary to rebuild it? I am a little frightened to use makemap command
    – it dev
    Aug 8 at 10:22










  • I seem to remember that restarting the sendmail service did this as well. But yeah you typically have to rebuild these files in order for sendmail to use them. BTW I just reinstalled sendmail on CentOS 7 and it does still come with a make command, so you should be able to run that if your setup has it. If you're pensive to do this, back up the whole /etc/mail dir 1st.
    – slm♦
    Aug 8 at 10:23







  • 1




    Good old sendmail...I prefered to deal with it editing .mc files...it would be interesting understanding the problem of the user, blocking users in sendmail wont prevent users/malware scripts form sending email/spam via TCP/25 if the infra-structure allows it.
    – Rui F Ribeiro
    Aug 8 at 10:48










  • @slm, may I only restart sendmail service after REJECTING user in access file? Will it help?
    – it dev
    Aug 8 at 11:13










  • @itdev - my suggestion was to try doing a restart after adding REJECT entry to see if it triggers a rebuild of access.db, but I'm 90% sure that you have to rebuild these manually using either rehash or the make command.
    – slm♦
    Aug 8 at 11:15














up vote
1
down vote













In Sendmail you can add this user to the /etc/mail/access database file (access.db) to disallow them from sending emails:



Put their address in the file /etc/mail/access:



user@my-domain.com REJECT


Then rebuild it:



$ makemap hash /etc/mail/access.db < /etc/mail/access


NOTE: From what I remember you may have to put several permutations of their email address in this file to stop them. so things like user@localhost, etc.



I do not have a sendmail setup handy, but you can typically use a Makefile command that's provided in newer implementations of sendmail.



For more controlling the sending/receiving via Sendmail you can do more specific controls like this in this file:



To:a1@server.vikas.com REJECT # Reject a1 user from recieving mails
From:a1@server.vikas.com REJECT # Reject a1 user from sending mails


References



  • How to enable/disable user's access to email (sendmail)





share|improve this answer




















  • Is it necessary to rebuild it? I am a little frightened to use makemap command
    – it dev
    Aug 8 at 10:22










  • I seem to remember that restarting the sendmail service did this as well. But yeah you typically have to rebuild these files in order for sendmail to use them. BTW I just reinstalled sendmail on CentOS 7 and it does still come with a make command, so you should be able to run that if your setup has it. If you're pensive to do this, back up the whole /etc/mail dir 1st.
    – slm♦
    Aug 8 at 10:23







  • 1




    Good old sendmail...I prefered to deal with it editing .mc files...it would be interesting understanding the problem of the user, blocking users in sendmail wont prevent users/malware scripts form sending email/spam via TCP/25 if the infra-structure allows it.
    – Rui F Ribeiro
    Aug 8 at 10:48










  • @slm, may I only restart sendmail service after REJECTING user in access file? Will it help?
    – it dev
    Aug 8 at 11:13










  • @itdev - my suggestion was to try doing a restart after adding REJECT entry to see if it triggers a rebuild of access.db, but I'm 90% sure that you have to rebuild these manually using either rehash or the make command.
    – slm♦
    Aug 8 at 11:15












up vote
1
down vote










up vote
1
down vote









In Sendmail you can add this user to the /etc/mail/access database file (access.db) to disallow them from sending emails:



Put their address in the file /etc/mail/access:



user@my-domain.com REJECT


Then rebuild it:



$ makemap hash /etc/mail/access.db < /etc/mail/access


NOTE: From what I remember you may have to put several permutations of their email address in this file to stop them. so things like user@localhost, etc.



I do not have a sendmail setup handy, but you can typically use a Makefile command that's provided in newer implementations of sendmail.



For more controlling the sending/receiving via Sendmail you can do more specific controls like this in this file:



To:a1@server.vikas.com REJECT # Reject a1 user from recieving mails
From:a1@server.vikas.com REJECT # Reject a1 user from sending mails


References



  • How to enable/disable user's access to email (sendmail)





share|improve this answer












In Sendmail you can add this user to the /etc/mail/access database file (access.db) to disallow them from sending emails:



Put their address in the file /etc/mail/access:



user@my-domain.com REJECT


Then rebuild it:



$ makemap hash /etc/mail/access.db < /etc/mail/access


NOTE: From what I remember you may have to put several permutations of their email address in this file to stop them. so things like user@localhost, etc.



I do not have a sendmail setup handy, but you can typically use a Makefile command that's provided in newer implementations of sendmail.



For more controlling the sending/receiving via Sendmail you can do more specific controls like this in this file:



To:a1@server.vikas.com REJECT # Reject a1 user from recieving mails
From:a1@server.vikas.com REJECT # Reject a1 user from sending mails


References



  • How to enable/disable user's access to email (sendmail)






share|improve this answer












share|improve this answer



share|improve this answer










answered Aug 8 at 10:11









slm♦

238k65491662




238k65491662











  • Is it necessary to rebuild it? I am a little frightened to use makemap command
    – it dev
    Aug 8 at 10:22










  • I seem to remember that restarting the sendmail service did this as well. But yeah you typically have to rebuild these files in order for sendmail to use them. BTW I just reinstalled sendmail on CentOS 7 and it does still come with a make command, so you should be able to run that if your setup has it. If you're pensive to do this, back up the whole /etc/mail dir 1st.
    – slm♦
    Aug 8 at 10:23







  • 1




    Good old sendmail...I prefered to deal with it editing .mc files...it would be interesting understanding the problem of the user, blocking users in sendmail wont prevent users/malware scripts form sending email/spam via TCP/25 if the infra-structure allows it.
    – Rui F Ribeiro
    Aug 8 at 10:48










  • @slm, may I only restart sendmail service after REJECTING user in access file? Will it help?
    – it dev
    Aug 8 at 11:13










  • @itdev - my suggestion was to try doing a restart after adding REJECT entry to see if it triggers a rebuild of access.db, but I'm 90% sure that you have to rebuild these manually using either rehash or the make command.
    – slm♦
    Aug 8 at 11:15
















  • Is it necessary to rebuild it? I am a little frightened to use makemap command
    – it dev
    Aug 8 at 10:22










  • I seem to remember that restarting the sendmail service did this as well. But yeah you typically have to rebuild these files in order for sendmail to use them. BTW I just reinstalled sendmail on CentOS 7 and it does still come with a make command, so you should be able to run that if your setup has it. If you're pensive to do this, back up the whole /etc/mail dir 1st.
    – slm♦
    Aug 8 at 10:23







  • 1




    Good old sendmail...I prefered to deal with it editing .mc files...it would be interesting understanding the problem of the user, blocking users in sendmail wont prevent users/malware scripts form sending email/spam via TCP/25 if the infra-structure allows it.
    – Rui F Ribeiro
    Aug 8 at 10:48










  • @slm, may I only restart sendmail service after REJECTING user in access file? Will it help?
    – it dev
    Aug 8 at 11:13










  • @itdev - my suggestion was to try doing a restart after adding REJECT entry to see if it triggers a rebuild of access.db, but I'm 90% sure that you have to rebuild these manually using either rehash or the make command.
    – slm♦
    Aug 8 at 11:15















Is it necessary to rebuild it? I am a little frightened to use makemap command
– it dev
Aug 8 at 10:22




Is it necessary to rebuild it? I am a little frightened to use makemap command
– it dev
Aug 8 at 10:22












I seem to remember that restarting the sendmail service did this as well. But yeah you typically have to rebuild these files in order for sendmail to use them. BTW I just reinstalled sendmail on CentOS 7 and it does still come with a make command, so you should be able to run that if your setup has it. If you're pensive to do this, back up the whole /etc/mail dir 1st.
– slm♦
Aug 8 at 10:23





I seem to remember that restarting the sendmail service did this as well. But yeah you typically have to rebuild these files in order for sendmail to use them. BTW I just reinstalled sendmail on CentOS 7 and it does still come with a make command, so you should be able to run that if your setup has it. If you're pensive to do this, back up the whole /etc/mail dir 1st.
– slm♦
Aug 8 at 10:23





1




1




Good old sendmail...I prefered to deal with it editing .mc files...it would be interesting understanding the problem of the user, blocking users in sendmail wont prevent users/malware scripts form sending email/spam via TCP/25 if the infra-structure allows it.
– Rui F Ribeiro
Aug 8 at 10:48




Good old sendmail...I prefered to deal with it editing .mc files...it would be interesting understanding the problem of the user, blocking users in sendmail wont prevent users/malware scripts form sending email/spam via TCP/25 if the infra-structure allows it.
– Rui F Ribeiro
Aug 8 at 10:48












@slm, may I only restart sendmail service after REJECTING user in access file? Will it help?
– it dev
Aug 8 at 11:13




@slm, may I only restart sendmail service after REJECTING user in access file? Will it help?
– it dev
Aug 8 at 11:13












@itdev - my suggestion was to try doing a restart after adding REJECT entry to see if it triggers a rebuild of access.db, but I'm 90% sure that you have to rebuild these manually using either rehash or the make command.
– slm♦
Aug 8 at 11:15




@itdev - my suggestion was to try doing a restart after adding REJECT entry to see if it triggers a rebuild of access.db, but I'm 90% sure that you have to rebuild these manually using either rehash or the make command.
– slm♦
Aug 8 at 11:15

















 

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