#!/bin/sh
# Various distributions have different paths for systemd unit files ...

SYSTEMD_UNIT_DIR=""
ResolveSystemdPaths()
{
    local UNIT_DIR_LIST="/usr/lib/systemd/system /lib/systemd/system"

    if [ -d /run/systemd/system ]; then
        # Find systemd unit directory
        for i in ${UNIT_DIR_LIST}; do
            if [ -d $i ]; then
                SYSTEMD_UNIT_DIR=${i}
                return 0
            fi
        done

        # Didn't fine unit directory, that's fatal
        echo "FATAL: Unable to resolve systemd unit directory!" 1>&2
        exit 1
    else
	return 1
    fi
}

RemoveGenericService() {
    if [ -f /etc/.omi_disable_service_control ]; then
        return 0
    fi

    SERVICE=$1
    if [ -z "$SERVICE" ]; then
        echo "FATAL: RemoveGenericService requires parameter (service name)" 1>&2
        exit 1
    fi

    # Stop the service in case it's running

    ResolveSystemdPaths
    # Does systemd install on this system
    if [ -d /run/systemd/system ]; then
        # Do we have a systemd unit file?
        if [ -f ${SYSTEMD_UNIT_DIR}/${SERVICE}.service ]; then
            /bin/systemctl stop ${SERVICE}
        fi
    fi

    if  [ -f /etc/init/${SERVICE}.conf ]; then
        initctl stop omid
    fi

    if [ -f /etc/init.d/${SERVICE} ]; then
        if [ -x /bin/systemctl ]; then
            /bin/systemctl stop ${SERVICE}
        elif [ -x /sbin/service ]; then
            /sbin/service ${SERVICE} stop
        elif [ -x /usr/sbin/service ]; then
            /usr/sbin/service ${SERVICE} stop
        elif [ -x /usr/sbin/invoke-rc.d ]; then
            /usr/sbin/invoke-rc.d ${SERVICE} stop
        else
            echo "Unrecognized service controller to stop ${SERVICE} service" 1>&2
            exit 1
        fi
    fi

    # Registered as a systemd service?
    #
    # Note: We've never deployed systemd unit files automatically in the %Files
    # section. Thus, for systemd services, it's safe to remove the file.

    if [ -f ${SYSTEMD_UNIT_DIR}/${SERVICE}.service ]; then
        echo "Unconfiguring ${SERVICE} (systemd) service ..."
        /bin/systemctl disable ${SERVICE}
        rm -f ${SYSTEMD_UNIT_DIR}/${SERVICE}.service
        /bin/systemctl daemon-reload
    fi

    if [ -f /etc/init/omid.conf ]; then
        echo "Unconfiguring omid (upstart) service ..."
        rm -f /usr/init/omid.conf
        initctl reload-configuration
    fi

    if [ -f /etc/init.d/${SERVICE} ]; then
        echo "Unconfiguring ${SERVICE} service ..."
        if [ -f /usr/sbin/update-rc.d ]; then
            /usr/sbin/update-rc.d -f ${SERVICE} remove
        elif [ -x /usr/lib/lsb/remove_initd ]; then
            /usr/lib/lsb/remove_initd /etc/init.d/${SERVICE}
        elif [ -x /sbin/chkconfig ]; then
            chkconfig --del ${SERVICE} > /dev/null
        else
            echo "Unrecognized Service Controller to unregister ${SERVICE} Service."
            exit 1
        fi
    fi
}

StopOmiService() {
    /opt/omi/bin/service_control stop
}

RemoveOmiService() {
    if [ -f /etc/.omi_disable_service_control ]; then
        return 0
    fi

    RemoveGenericService omid
    [ -f /etc/init.d/omid ] && rm /etc/init.d/omid
    [ -f /etc/init/omid.conf ] && rm /etc/init/omid.conf
}

ConfigureOmiService() {
    # If the marker file /etc/.omi_disable_service_control exists,
    # OMI will not be configured with service manager. This may be used in a container
    # environment, where service manager does not work reliably.
    if [ ! -f /etc/.omi_disable_service_control ]; then
      echo "Configuring OMI service ..."
      if [ -d /run/systemd/system ]; then
          # systemd
          ResolveSystemdPaths
          cp /opt/omi/bin/support/omid.systemd ${SYSTEMD_UNIT_DIR}/omid.service
          /bin/systemctl daemon-reload
          /bin/systemctl enable omid
      elif [ -x /sbin/initctl -a -f /etc/init/networking.conf -a ! -z "$(/sbin/initctl list >/dev/null 2>&1 && echo $?)" ]; then
          # If we have /sbin/initctl, we have upstart.
          # Note that the upstart script requires networking,
          # so only use upstart if networking is controlled by upstart (not the case in RedHat 6)
          cp /opt/omi/bin/support/omid.upstart /etc/init/omid.conf

          # initctl registers it with upstart
          initctl reload-configuration
      else
          cp /opt/omi/bin/support/omid.initd /etc/init.d/omid

          if [ -x /usr/sbin/update-rc.d ]; then
              update-rc.d omid defaults > /dev/null
          elif [ -x /usr/lib/lsb/install_initd ]; then
              /usr/lib/lsb/install_initd /etc/init.d/omid
          elif [ -x /sbin/chkconfig ]; then
              chkconfig --add omid > /dev/null
          else
              echo "Unrecognized Service Controller to configure OMI Service."
              exit 1
          fi
      fi
    fi
    
    /opt/omi/bin/service_control start
}

ConfigureCronForLogRotate()
{
    echo "Checking if cron is installed..."
    # warn user that he need to install cron if cron doesn't install
    which cron >/dev/null 2>&1
    if [ $? -ne 0 ]; then
        which crond >/dev/null 2>&1
        if [ $? -ne 0 ]; then
            echo "WARNING: LogRotate can't be enabled, please install cron at first!"
            return
        fi
    fi

    echo "Checking if cron/crond service is started..."
    # warn user that he need to start cron/crond service if cron doesn't start
    cronid=$(pidof cron > /dev/null 2>&1)
    crondid=$(pidof crond > /dev/null 2>&1)
    if [ ! -z "$cronid" -a ! -z "$crondid" ]; then
        echo "WARNING: LogRotate can be enabled, but please start cron/crond service!"
    fi

    echo "Set up a cron job to OMI logrotate every 15 minutes"
    # create the cron file if it doesn't exist
    if [ ! -f /etc/cron.d/omilogrotate ]; then
        (echo "*/15 * * * * root /usr/sbin/logrotate /etc/logrotate.d/omi --state /var/opt/omi/log/omi-logrotate.status >/dev/null 2>&1" > /etc/cron.d/omilogrotate) > /dev/null 2>&1
    fi
}


# dpkg -P omi will remove /opt, to fix the issue, we touch a file under /opt/omi
if [ "$1" = "purge" -o "$1" = "remove" ]; then
    [ ! -f /opt/omi/.omi_not_delete ] && touch /opt/omi/.omi_not_delete
fi

# If we're called for upgrade, don't do anything
if [ "$1" != "upgrade" -a "$1" != "purge" ]; then
    RemoveOmiService
    /opt/omi/bin/support/config_keytab_update.sh --unconfigure
fi

GetNewPAMConfig_file() {
    #
    # See if we have special marker file to use for PAM
    # For ease in customer debugging, return bad config if file is bad
    #
    if [ -f /etc/opt/omi/conf/pam.conf ]; then
        # PAM configuration file found; use that
        omi_conf=`cat /etc/opt/omi/conf/pam.conf`
        if [ $? -ne 0 ]; then
            # We had some sort of problem reading file
            # STDERR should have output; just return failure
            return 1
        fi

        echo "Used custom PAM configuration from /etc/opt/omi/conf/pam.conf"
        return 0
    fi

    #
    # Get configuration for sshd, service modules types auth and account
    #
    sshd_conf=`egrep "^[# ]*sshd[ 	]+(auth|account)" /etc/pam.conf`
    if [ $? -ne 0 ]; then
        # No match found
        # sshd not explicitly configured.
        # Check to see if "other" is configured
        other_conf=`egrep "^[# ]*other[ 	]+(auth|account)" /etc/pam.conf`
        if [ $? -eq 0 ]; then
            # "other" was found - use that (do not write any sort of new PAM configuraton)
            return 0
        fi
        # Use passwd

        if [ -e "/etc/debian_version" ]; then
            sshd_conf=`printf "omi auth required pam_env.so\nomi auth required pam_unix.so nullok_secure\nomi account required pam_unix.so\nomi session required pam_limits.so"`
        elif [ ! -e "/etc/sysconfig/networking" ] && [ ! -e"/etc/sysconfig/network-scripts"]; then
            sshd_conf=`printf "omi auth include common-auth\nomi auth required pam_nologin.so\nomi account include common-account"`
        else
            sshd_conf=`printf "omi auth include system-auth\nomi account required pam_nologin.so\nomi account include system-auth"`
        fi
    fi

    #
    # Substitute sshd with omi.
    #
    omi_conf=`echo "$sshd_conf" | sed "s/sshd/omi/g"`
    if [ $? -ne 0 ]; then
        echo "can't parse /etc/pam.conf"
        return 1
    fi
}

GetNewPAMConfig_dir() {
    #
    # See if we have special marker file to use for PAM
    # For ease in customer debugging, return bad config if file is bad
    #
    if [ -f /etc/opt/omi/conf/pam.conf ]; then
        # PAM configuration file found; use that
        omi_conf=`cat /etc/opt/omi/conf/pam.conf`
        if [ $? -ne 0 ]; then
            # We had some sort of problem reading file
            # STDERR should have output; just return failure
            return 1
        fi

        echo "Used custom PAM configuration from /etc/opt/omi/conf/pam.conf"
        return 0
    fi

    #
    # Get configuration for sshd, service modules types auth and account
    #
    sshd_conf=`egrep "(auth|account)" /etc/pam.d/sshd 2> /dev/null`
    if [ $? -ne 0 ]; then
        # No match found
        # sshd not explicitly configured.
        # Use passwd

        if [ -e "/etc/debian_version" ]; then
            sshd_conf=`printf "auth required pam_env.so\n auth required pam_unix.so nullok_secure\n account required pam_unix.so\n session required pam_limits.so"`
        elif [ ! -e "/etc/sysconfig/networking" ] && [ ! -e"/etc/sysconfig/network-scripts"]; then
            sshd_conf=`printf "auth include common-auth\n auth required pam_nologin.so\n account include common-account"`
        else
            sshd_conf=`printf "auth include system-auth\n account required pam_nologin.so\n account include system-auth"`
        fi
    fi

    omi_conf=$sshd_conf
}

#
#
# ConfigurePAM
#
#
ConfigurePAM_file() {
    #
    # First check if omi is already configured in pam.conf
    #
    grep -s "^[# ]*omi" /etc/pam.conf > /dev/null 2>&1
    if [ $? -eq 0 ]; then
        # Match found
        # Looks like omi is already configured
        echo "omi already configured"
        return 0
    fi

    GetNewPAMConfig_file

    #
    # Only update pam.conf if we are returning some new configuration
    if [ "$omi_conf" ]; then
        # Write the final configuration to pam.conf
        #
        # copy file first and modify this copy, so in case of low disk space we preserve the original file
        cp /etc/pam.conf /etc/pam.conf.omi-copy && printf "# The configuration of omi is generated by the omi installer.\n$omi_conf\n# End of section generated by the omi installer.\n" >> /etc/pam.conf.omi-copy
        if [ $? -ne 0 ]; then
            echo "can't update file /etc/pam.conf.omi-copy"
            rm -f /etc/pam.conf.omi-copy
            return 1
        fi
        # verify that complete file was written
        grep "# End of section generated by the omi installer." /etc/pam.conf.omi-copy > /dev/null 2>&1
        if [ $? -ne 0 ]; then
            echo "can't update file /etc/pam.conf.omi-copy"
            rm -f /etc/pam.conf.omi-copy
            return 1
        fi
        # use move to substitute original file with verified copy
        mv /etc/pam.conf.omi-copy /etc/pam.conf
        if [ $? -ne 0 ]; then
            echo "can't replace /etc/pam.conf"
            return 1
        fi
    fi
}

ConfigurePAM_dir() {
    #
    # First check if omi is already configured
    #
    if [ -f /etc/pam.d/omi ]; then
        # Match found
        # Looks like omi is already configured
        echo "omi already configured"
        return 0
    fi

    GetNewPAMConfig_dir

    echo "#%%PAM-1.0
# The configuration of omi is generated by the omi installer.
$omi_conf" > /etc/pam.d/omi
    if [ $? -ne 0 ]; then
        echo "can't create /etc/pam.d/omi"
        return 1
    fi
}


ConfigurePAM() {
    #
    # Check if pam is configured with single
    # configuration file or with configuration
    # directory.
    #
    if [ -s /etc/pam.conf ]; then
        ConfigurePAM_file
    elif [ -d /etc/pam.d ]; then
        ConfigurePAM_dir
    else
        # No pam configuration.
        echo "PAM does not seem to be configured."
        echo "Checked both /etc/pam.conf and /etc/pam.d."
        return 1
    fi
    return 0
}

GetCurrentPAMConfig_file() {
    omi_current_conf=`grep "^[#\t]*omi" /etc/pam.conf`
}

GetCurrentPAMConfig_dir() {
    omi_current_conf=`cat /etc/pam.d/omi | grep -v "#%%PAM-1.0" | grep -v "# The configuration of omi is generated by the omi installer."`
}

#
#
# UnconfigurePAM
#
#
UnconfigurePAM_file() {
    # Configured with single file


    #
    # Get all lines except omi configuration
    #
    pam_configuration=`grep -v "^[#	]*omi" /etc/pam.conf | grep -v "# The configuration of omi is generated by the omi installer." | grep -v "# End of section generated by the omi installer."`
    if [ $? -ne 0 ]; then
        # omi not configured in PAM
        return 0
    fi

    #
    # Write it back (to the copy first)
    #
    cp -p /etc/pam.conf /etc/pam.conf.tmp
    echo "$pam_configuration" > /etc/pam.conf.tmp
    if [ $? -ne 0 ]; then
        echo "can't write to /etc/pam.conf.tmp"
        return 1
    fi
    mv /etc/pam.conf.tmp /etc/pam.conf
    if [ $? -ne 0 ]; then
        echo "can't replace /etc/pam.conf"
        return 1
    fi

}

UnconfigurePAM_dir() {
    # Configured with directory
    if [ -f /etc/pam.d/omi ]; then

        rm -f /etc/pam.d/omi
        return 0
    fi

}

UnconfigurePAM() {
    #
    # Check if pam is configured with single
    # configuration file or with configuration
    # directory.
    #
    if [ -s /etc/pam.conf ]; then
        UnconfigurePAM_file
    elif [ -d /etc/pam.d ]; then
        UnconfigurePAM_dir
    fi
}

UnconfigurePAM
exit 0