Manage iRedAPD (white/blacklists, greylisting, and more)

Manage iRedAPD (white/blacklists, greylisting, and more)

Note

All iRedAPD features listed in current page can be managed with our web-based admin panel - iRedAdmin-Pro.

Introduce iRedAPD

iRedAPD is a simple Postfix policy server, written in Python, with plugin support. it listens on port 7777 by default, and runs as a low-privileged user iredapd.

How to disable iRedAPD service

To disable iRedAPD service:

please remove all check_policy_service inet:127.0.0.1:7777 in Postfix config file /etc/postfix/main.cf (Linux/OpenBSD) or /usr/local/etc/postfix/main.cf (FreeBSD).
Restart or reload Postfix service.
Disable iredapd service.

How to enable or disable iRedAPD plugins

iRedAPD plugin is Python file under /opt/iredapd/plugins/ directory. To enable a plugin, please find line plugins = in iRedAPD config file /opt/iredapd/settings.py, for example:

plugins = ['reject_null_sender', 'amavisd_wblist', 'greylisting', 'throttle']

If you want to enable plugin reject_sender_login_mismatch (file /opt/iredapd/plugins/reject_sender_login_mismatch.py), please add the plugin name in plugins = like below, and restart iRedAPD service:

plugins = ['reject_null_sender', 'amavisd_wblist', 'greylisting', 'throttle', 'reject_sender_login_mismatch']

The priorities of plugins shipped in iRedAPD are hard-coded, so the order of plugin name in plugins = doesn't matter.

To disable a plugin, just remove the plugin name and restart iRedAPD service.

How to add custom settings

iRedAPD has some default settings in file /opt/iredapd/libs/default_settings.py, but you should never modify it. Instead, you should copy the settings you want to modify from /opt/iredapd/libs/default_settings.py to /opt/iredapd/settings.py, then update it with new values. This way you will keep custom settings after upgrading iRedAPD -- because iRedAPD upgrade tool will copy /opt/iredapd/settings.py to new iRedAPD release during upgrading.

Feature: Sender address control

Plugin reject_sender_login_mismatch will reject emails if:

smtp authentication username (sasl_username) is different than than sender address (From:). This is usually called sender login mismatch. Note: This can be performed by Postfix with restriction rule reject_sender_login_mismatch in smtpd_sender_restrictions =.
sender address is forged (sender doesn't perform smtp auth and sender domain is hosted on localhost)

It offers some parameters to control whether or not to reject email:

for forged sender address checking:

# Check whether sender is forged in message sent without smtp auth.
CHECK_FORGED_SENDER = True

# If you allow someone or some service providers to send email as forged
# (your local) address, you can list all allowed addresses in this parameter.
# For example, if some ISPs may send email as 'user@mydomain.com' (mydomain.com
# is hosted on your server) to you, you should add `user@mydomain.com` as one
# of forged senders.
# Sample: ALLOWED_FORGED_SENDERS = ['user@mydomain.com', 'mydomain.com']
ALLOWED_FORGED_SENDERS = []

for sender login mismatch:

# Allow sender login mismatch for specified senders or sender domains.
#
# Sample setting: allow local user `user@local_domain_1.com` and all users
# under `local_domain_2.com` to send email as other users.
#
#   ALLOWED_LOGIN_MISMATCH_SENDERS = ['user@local_domain_1.com', 'local_domain_2.com']
ALLOWED_LOGIN_MISMATCH_SENDERS = []

# Strictly allow sender to send as one of user alias addresses. Default is True.
ALLOWED_LOGIN_MISMATCH_STRICTLY = True

# Allow member of mail lists/alias account to send email as mail list/alias
# ('From: <email_of_mail_list>' in mail header). Default is False.
ALLOWED_LOGIN_MISMATCH_LIST_MEMBER = False

Feature: White/Blacklisting

How to disable white/blacklists completely

To disable white/blacklists completely, please remove plugin name amavisd_wblist in iRedAPD config file /opt/iredapd/settings.py, parameter plugins =:

plugins = [..., 'amavisd_wblist', ...]

Restarting iRedAPD service is required.

Manage white/blacklists

White/blacklisting is available in iRedAPD-1.4.4 and later releases.

Script tools/wblist_admin.py is available in iRedAPD-1.7.0 and later releases.

White/blacklisting is controlled by plugin amavisd_wblist (file /opt/iredapd/plugins/amavisd_wblist.py), you can manage it with script /opt/iredapd/tools/wblist_admin.py.

Available arguments

    --outbound
        Manage white/blacklist for outbound messages.

        If no '--outbound' argument, defaults to manage inbound messages.

    --account account
        Add white/blacklists for specified (local) account. Valid formats:

            - a single user: username@domain.com
            - a single domain: @domain.com
            - entire domain and all its sub-domains: @.domain.com
            - anyone: @. (the ending dot is required)

        if no '--account' argument, defaults to '@.' (anyone).

    --add
        Add white/blacklists for specified (local) account.

    --delete
        Delete specified white/blacklists for specified (local) account.

    --delete-all
        Delete ALL white/blacklists for specified (local) account.

    --list
        Show existing white/blacklists for specified (local) account. If no
        account specified, defaults to manage server-wide white/blacklists.

    --whitelist sender1 [sender2 sender3 ...]
        Whitelist specified sender(s). Multiple senders must be separated by a space.

    --blacklist sender1 [sender2 sender3 ...]
        Blacklist specified sender(s). Multiple senders must be separated by a space.

    WARNING: Do not use --list, --add-whitelist, --add-blacklist at the same time.

Sample usages

Show and add server-wide whitelists or blacklists:

# python wblist_admin.py --list --whitelist
# python wblist_admin.py --list --blacklist
# python wblist_admin.py --add --whitelist 192.168.1.10 user@domain.com
# python wblist_admin.py --add --blacklist 172.16.1.10 user@domain.com

For per-user or per-domain whitelists and blacklists, please use option --account. for example:

# python wblist_admin.py --account @mydomain.com --add --whitelist 192.168.1.10 user@example.com
# python wblist_admin.py --account user@mydomain.com --add --blacklist 172.16.1.10 baduser@example.com

# python wblist_admin.py --account @mydomain.com --list --whitelist
# python wblist_admin.py --account user@mydomain.com --list --blacklist

Feature: Greylisting

Note

Greylisting is available in iRedAPD-1.7.0 and later releases.

For technical details about greylisting, please visit http://greylisting.org/

How to disable greylisting completely

To disable greylisting completely, please remove plugin name greylisting in iRedAPD config file /opt/iredapd/settings.py, parameter plugins =:

plugins = [..., 'greylisting', ...]

Restarting iRedAPD service is required.

General settings

There're several settings for greylisting behaviour, default values are defined in /opt/iredapd/libs/default_settings.py. If you want to modify them, please add the settings with custom values in /opt/iredapd/settings.py.

GREYLISTING_MESSAGE: the rejection message which will be sent to sender server. Default is Intentional policy rejection, please try again later.
GREYLISTING_BLOCK_EXPIRE: Time (in MINUTES) to wait before client retrying, client will be rejected if retires too soon (in less than specified minutes). Defaults to 15 minutes.
GREYLISTING_AUTH_TRIPLET_EXPIRE: Disable greylisting for how long (in DAYS) for clients which passed greylisting (retried and delivered). It's also used to clean up old greylisting tracking records. Defaults to 30 days.
GREYLISTING_UNAUTH_TRIPLET_EXPIRE: Time (in DAYS) to keep tracking records if client didn't pass the greylisting, and no further deliver attempts. Defaults to 2 days.

Manage greylisting settings

Script tools/greylisting_admin.py is available in iRedAPD-1.8.0 and later releases.

Greylisting is controlled by plugin greylisting (file /opt/iredapd/plugins/greylisting.py), you can manage it with script /opt/iredapd/tools/greylisting_admin.py.

Available arguments

    --list-whitelist-domains
        Show ALL whitelisted sender domain names (in `greylisting_whitelist_domains`)

    --list-whitelists
        Show ALL whitelisted sender addresses (in `greylisting_whitelists`)

    --whitelist-domain
        Whitelist the IP addresses/networks in SPF record of specified sender
        domain for greylisting service. Whitelisted domain is stored in sql
        table `greylisting_whitelist_domains`.

    --remove-whitelist-domain
        Remove whitelisted sender domain

    --list
        Show ALL existing greylisting settings.

    --from <from_address>
    --to <to_address>
        Manage greylisting setting from email which is sent from <from_address>
        to <to_address>.

        Valid formats for both <from_address> and <to_address>:

            - a single user: username@domain.com
            - a single domain: @domain.com
            - entire domain and all its sub-domains: @.domain.com
            - anyone: @. (the ending dot is required)

        if no '--from' or '--to' argument, defaults to '@.' (anyone).

    --enable
        Explicitly enable greylisting for specified account.

    --disable
        Explicitly disable greylisting for specified account.

    --delete
        Delete specified greylisting setting.

Sample usages

List all existing greylisting settings:

python greylisting_admin.py --list

List all whitelisted sender domain names (in SQL table greylisting_whitelist_domains):

python greylisting_admin.py --list-whitelist-domains

List all whitelisted sender addresses (in SQL table greylisting_whitelists):

python greylisting_admin.py --list-whitelists

Whitelist IP networks/addresses specified in sender domain:

python greylisting_admin.py --whitelist-domain --from '@example.com'

This is same as:

python spf_to_whitelist_domains.py --submit example.com

Remove a whitelisted sender domain:

python greylisting_admin.py --remove-whitelist-domain --from '@example.com'

Enable greylisting for emails which are sent from anyone to local mail domain example.com:

python greylisting_admin.py --enable --to '@example.com'

Disable greylisting for emails which are sent from anyone to local mail user user@example.com:

python greylisting_admin.py --disable --to 'user@example.com'

Disable greylisting for emails which are sent from gmail.com to local mail user user@example.com:

python greylisting_admin.py --disable --from '@gmail.com' --to 'user@example.com'

Delete greylisting setting for emails which are sent from anyone to local domain test.com:

python greylisting_admin.py --delete --to '@test.com'

RECOMMENDED: Additional greylisting whitelist support

Seems many companies setup their mail servers to re-deliver returned email immediately from another server, this causes trouble with greylisting.

Possible solutions:

Disable greylisting on your server completely.
[Recommended] Whitelist IP addresses/networks of their mail servers.

For solution #2, you can whitelist those mail servers with script /opt/iredapd/tools/spf_to_greylist_whitelists.py.

Attention

Script tools/spf_to_greylist_whitelists.py is available in iRedAPD-1.8.0 and later releases.

It queries SPF and MX records of specified mail domain names, then store all converted IP addresses/networks defined in SPF/MX records in SQL table iredapd.greylisting_whitelists.

To whitelist IP addresses/networks of some mail domain, for example, outlook.com, microsoft.com, please run command like below:

# cd /opt/iredapd/tools/
# python spf_to_greylist_whitelists.py outlook.com microsoft.com

If you want to whitelist more mail domains, just run the command with the domain names like above sample.

Since iRedAPD-1.8.0, we have SQL table iredapd.greylisting_whitelist_domains to store these mail domain names. if you run spf_to_greylist_whitelists.py without any argument, it will fetch all mail domains stored in sql table greylisting_whitelist_domains instead of fetching from command line arguments.

# python spf_to_greylist_whitelists.py

You should setup a cron job to run this script, so that it can keep the IP addresses/networks up to date. iRedMail sets up the cron job to run every 10 or 30 minutes, like below:

*/30   *   *   *   *   /usr/bin/python /opt/iredapd/tools/spf_to_greylist_whitelists.py &>/dev/null

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