Centos自定义motd

之前在ArchLinux上弄个motd，最近在Centos上按之前的笔记操作一边，发现有很多不一样的地方。

步骤

首先，需要有用于显示的脚本文件，放在/etc/update_motd.d文件夹下，然后使用motd-update脚本执行/etc/update_motd.d文件夹下的脚本。最后，在pam中加入motd-update脚本。

motd-update

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#!/bin/sh
# /usr/bin/update-motd
run-parts-debian --lsbsysinit /etc/update_motd.d
#run-parts /etc/update_motd.d

会发现没有run-parts-debian这个命令，其实这个是我拷贝网上的脚本实现的/usr/bin/run-parts-debian，因为Contos的run-parts没有--lsbsysinit参数。

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cat /usr/bin/run-parts-debian 
#!/usr/bin/env bash

# run-parts - concept taken from Debian
# http://www.unix.com/man-page/linux/8/run-parts/
# with extensions from Ubuntu
# http://manpages.ubuntu.com/manpages/trusty/man8/run-parts.8.html

# keep going when something fails
set +e
# pipefail is required for --report support
set -o pipefail

usage() {
    echo "run-parts  [--test]  [--verbose]  [--report]  [--umask=umask] [--lsbsysinit] [--regex=REGEX]
           [--arg=argument] [--exit-on-error] [--help] [--list] [--reverse]  [--]  DIRECTORY"
}

help() {
    echo "
NAME
       run-parts - run scripts or programs in a directory

SYNOPSIS
       run-parts  [--test]  [--verbose]  [--report]  [--umask=umask] [--lsbsysinit] [--regex=REGEX]
       [--arg=argument] [--exit-on-error] [--help] [--list] [--reverse]  [--]  DIRECTORY

DESCRIPTION
       run-parts runs all the executable files named within constraints described below, found in
       directory directory.  Other files and directories are silently ignored.

       If neither the --lsbsysinit option nor the --regex option is given  then  the  names  must
       consist  entirely of ASCII upper- and lower-case letters, ASCII digits, ASCII underscores,
       and ASCII minus-hyphens.

       If the --lsbsysinit option is given,  then  the  names  must  not  end  in  .dpkg-old   or
       .dpkg-dist  or  .dpkg-new  or  .dpkg-tmp,  and must belong to one or more of the following
       namespaces: the LANANA-assigned namespace (^[a-z0-9]+$); the LSB hierarchical and reserved
       namespaces  (^_?([a-z0-9_.]+-)+[a-z0-9]+$);  and the Debian cron script namespace (^[a-zA-
       Z0-9_-]+$).

       If the --regex option  is  given,  the  names  must  match  the  custom  extended  regular
       expression specified as that option's argument.

       Files  are  run	in  the  lexical sort order of their names unless the --reverse option is
       given, in which case they are run in the opposite order.

OPTIONS
       --test print the names of the scripts which would be run, but don't actually run them.

       --list print the names of the all matching files (not limited to executables),  but  don't
          actually run them. This option cannot be used with --test.

       -v, --verbose
          print the name of each script to stderr before running.

       --report
          similar  to  --verbose,  but  only prints the name of scripts which produce output.
          The script's name is printed to whichever of stdout or stderr the script produces
          output on. The script's name is not printed to stderr if --verbose also specified.

       --reverse
          reverse the scripts' execution order.

       --exit-on-error
          exit as soon as a script returns with a non-zero exit code.

       --umask=umask
          sets  the  umask to umask before running the scripts.  umask should be specified in
          octal.  By default the umask is set to 022.

       --lsbsysinit
          filename must be in one or more of either the LANANA-assigned namespace, the LSB
          namespaces - either hierarchical or reserved - or the Debian cron script namespace.

       --regex=REGEX
          validate filenames against custom extended regular expression REGEX

       -a, --arg=argument
          pass argument to the scripts.  Use --arg once for each argument you want passed.

       --     specifies that this is the end of the options.  Any filename after -- will  be  not
          be interpreted as an option even if it starts with a hyphen.

       -h, --help
          display usage information and exit.
"
}

report-and-pipe() {
    rline="$1"
    while IFS= read -r line; do
        echo -en "$rline" ; echo "$line";
        unset rline;
    done;
}

if [ $# -lt 1 ]; then
    usage
    exit 1
fi

args=""
dir=""
umask=""

for i in "$@"; do
    if [ ${append_arg:-0} = 1 ]; then
        args="$args $i"
        append_arg=0
        continue
    fi
    case $i in
        --list)
            list=1
            ;;
        --test)
            test=1
            ;;
        --verbose|-v)
            verbose=1
            ;;
        --report)
            report=1
            ;;
        --reverse)
            reverse=1
            ;;
        --lsbsysinit)
            lsbsysinit=1
            ;;
        --regex)
            regex="${i#*=}"
            ;;
        --arg=*)
            args="$args ${i#*=}"
            ;;
        -a)
            append_arg=1
            ;;
        --umask=*)
            umask="${i#*=}"
            ;;
        --help|-h)
            help
            exit 0
            ;;
        --exit-on-error)
            exit_on_error=1
            ;;
        --)
            # -- end of options
            ;;
        -*)
            echo Unknown argument: $i > /dev/stderr
            echo Rest of arguments: $* > /dev/stderr
            usage
            exit 1
            ;;
        *)
            # directory
            dir=$i
            break
            ;;
    esac
done

if [[ "x$dir" = "x" && ! -d "$dir" ]]; then
    echo "Not a directory: '$dir'"
    usage
    exit 1
fi

# Ignore *~ and *, scripts
filelist=$(LC_ALL=C; ls -1 "${dir}" | grep -vEe '[~,]$')

if [ ${reverse:-0} = 1 ]; then
    filelist=$(echo "$filelist" | sort -r)
fi

echo "$filelist" | while read bname ; do
    fpath="${dir%/}/${bname}"
    [ -d "${fpath}" ] && continue
    # Don't run *.{disabled,rpmsave,rpmorig,rpmnew,swp,cfsaved} scripts
    [ "${bname%.disabled}" != "${bname}" ] && continue
    [ "${bname%.cfsaved}" != "${bname}" ] && continue
    [ "${bname%.rpmsave}" != "${bname}" ] && continue
    [ "${bname%.rpmorig}" != "${bname}" ] && continue
    [ "${bname%.rpmnew}" != "${bname}" ] && continue
    [ "${bname%.swp}" != "${bname}" ] && continue
    [ "${bname%,v}" != "${bname}" ] && continue

    if [ ${lsbsysinit:-0} = 1 ]; then
        # Don't run *.{dpkg-old,dpkg-dist,dpkg-new,dpkg-tmp} scripts
        [ "${bname%.dpkg-old}" != "${bname}" ] && continue
        [ "${bname%.dpkg-dist}" != "${bname}" ] && continue
        [ "${bname%.dpkg-new}" != "${bname}" ] && continue
        [ "${bname%.dpkg-tmp}" != "${bname}" ] && continue
        # Adhere to LANANA-assigned LSB (hierarchical and reserved) and the Debian cron script namespaces
        [[ ! "${bname}" =~ ^[a-z0-9]+$ ]] && \
        [[ ! "${bname}" =~ ^_?([a-z0-9_.]+-)+[a-z0-9]+$ ]] && \
        [[ ! "${bname}" =~ ^[a-zA-Z0-9_-]+$ ]] && continue
    fi

    if [ "x$regex" != "x" ]; then
        [[ ! "${bname}" =~ $regex ]] && continue
    fi

    if [ -e "${fpath}" ]; then
        if [ -r $dir/whitelist ]; then
            grep -q "^${bname}$" $dir/whitelist && continue
        fi

        if [ ${list:-0} = 1 ]; then
            echo "${fpath}" $args;
            continue
        fi

        if [ -x "${fpath}" ]; then
            if [ ${test:-0} = 1 ]; then
                echo "${fpath}" $args;
                continue
            fi
            if [ "$RANDOMIZE" != "" ]; then
                let "rtime = $RANDOM"
                if [ "$RANDOMTIME" != "" ]; then
                    let "rtime %= $RANDOMTIME"
                else
                    let "rtime %= 300"
                fi
                sleep $rtime
            fi

            # run executable files
            if [ ${verbose:-0} = 1 ]; then
                echo "${fpath}" $args > /dev/stderr
            fi

            if [ "x$umask" != "x" ]; then
                umask $umask
            fi

            if [ ${report:-0} = 1 ]; then
                oline="${fpath}\n"
                # do not report script name over stderr in verbose mode
                # no duplicates are needed
                if [ ${verbose:-0} = 1 ]; then
                    eline=""
                else
                    eline="${fpath}\n"
                fi
                { "${fpath}" $args 2>&1 1>&3 3>&- |
                    # handle stderr redirected to stdout
                    report-and-pipe "$eline"
                } 3>&1 1>&2 |
                    # handle stdout
                    report-and-pipe "$oline"
            else
                "${fpath}" $args
            fi

            rc=${PIPESTATUS[0]}

            if [ ${verbose:-0} = 1 ]; then
                echo "${fpath}" $args exit status $rc > /dev/stderr
            fi

            if [ ${rc:-0} != 0 ]; then
                if [ ${exit_on_error:-0} = 1 ]; then
                    exit $rc
                fi
            fi
        fi
    fi
done

exit 0

pam

在/etc/pam.d/sshd添加

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session    optional     pam_exec.so   stdout /usr/bin/update-motd
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#%PAM-1.0
#/etc/pam.d/sshd
auth	   required	pam_sepermit.so
auth       substack     password-auth
auth       include      postlogin
# Used with polkit to reauthorize users in remote sessions
-auth      optional     pam_reauthorize.so prepare
account    required     pam_nologin.so
account    include      password-auth
password   include      password-auth
# pam_selinux.so close should be the first session rule
session    required     pam_selinux.so close
session    required     pam_loginuid.so
# pam_selinux.so open should only be followed by sessions to be executed in the user context
session    required     pam_selinux.so open env_params
session    required     pam_namespace.so
session    optional     pam_keyinit.so force revoke
session    include      password-auth
session    include      postlogin
session    optional     pam_exec.so   stdout /usr/bin/update-motd
# Used with polkit to reauthorize users in remote sessions
-session   optional     pam_reauthorize.so prepare

/etc/motd-update.d

新建/etc/update_motd.d文件夹

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sudo mkdir /etc/update_motd.d

增加脚本

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#!/bin/bash
#/etc/update_motd.d/00-banner
color="\e[1;33m"
clear="\e[m"
# figlet  -f chunky "ASRock" 
echo -e "${color} ______               __               
|      |.-----.-----.|  |_.-----.-----.
|   ---||  -__|     ||   _|  _  |__ --|
|______||_____|__|__||____|_____|_____|"
echo -e ${clear}
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#!/bin/bash
# /etc/update_motd.d/30-body 
#
# GREETER SCRIPT FOR ARCHLINUX SRV
# https://github.com/Gazeka74/archserver-motd/blob/master/arch-greeter

#########################################
#
#		VARIABLES
#
#########################################

# Kernel information
kernel="$(uname -sr)"

# Uptime
uptime="$(uptime -p | sed 's/up //;s/,//g')"

# Numbers of packages installed
# packages="$(pacman -Q | wc -l)"

# Numbers of updates pending
# updates_count="$(checkupdates | wc -l)"

# Numbers of IP bannedi

# f2b="$(sudo fail2ban-client status sshd | grep 'Currently banned' | rev | cut -f 1 | rev)"
# banned="$f2b IP banned"
# f2b="$(sudo fail2ban-client status sshd | grep 'Currently banned' | rev | cut -f 1 | rev)"
# banned="IP banned"

# Text to be displayed
# if (( $updates_count > 0 )); then
# 	updates="$updates_count updates pending"
# else
# 	updates="$updates_count update pending" 
# fi

## Filesystem
# Number of '-' to be displayed on the filesystem occupation
number=30

# /boot
read boot_a boot_s boot_m boot_pcent <<< "$(df -h --output=avail,size,target,pcent /boot | tail -1)"

# /
read root_a root_s root_m root_pcent<<< "$(df -h --output=avail,size,target,pcent / | tail -1)"

# /home
read home_a home_s home_m home_pcent<<< "$(df -h --output=avail,size,target,pcent /home | tail -1)"

# get free memory
read USED FREE TOTAL <<<$(free -htm | grep "Mem" | awk {'print $3,$4,$2'})
read USEDSW FREESW TOTALSW <<<$(free -htm | grep "Swap" | awk {'print $3,$4,$2'})

# get processes
PROCESS=`ps -eo user=|sort|uniq -c | awk '{ print $2 " " $1 }'`
PROCESS_ALL=`echo "$PROCESS"| awk {'print $2'} | awk '{ SUM += $1} END { print SUM }'`
PROCESS_ROOT=`echo "$PROCESS"| grep root | awk {'print $2'}`
PROCESS_USER=`echo "$PROCESS"| grep -v root | awk {'print $2'} | awk '{ SUM += $1} END { print SUM }'`

## Colors
bold="\033[01;1m"
black="\033[01;36m"
red="\033[01;31m"
green="\033[01;32m"
yellow="\033[01;33m"
blue="\033[01;34m"
magenta="\033[01;35m"
cyan="\033[01;36m"
white="\033[01;37m"
reset="\033[0m"

beg="${c1} ${c0}"			# in front of information
c0="${reset}${blue}${bold}"		# logo + text 1 color
c1="${reset}${white}${bold}"		# text 2 color
upd_color=""				# updates based on amount

#########################################
#
#		FUNCTIONS
#
#########################################

# Displays a progression bar of the FS depending on the available space and the total space
# $PARAM1 = percentage used
bar () {
	temp1="${1%?}"			# Remove last character
	temp2=$(($temp1*$number/100))	# Number of #

	str="["				# Initiate

	# Add a color to the output
	if (($temp1 > 75)); then
		str+="${red}"
	elif (($temp1 > 50)); then
		str+="${yellow}"
	elif (($temp1 > 25)); then
		str+="${green}"
	else 
		str+="${white}"
	fi
	# Fill with '#'
	for i in $(seq 1 $temp2)
	do
		str+="="
	done

	# reset the color
	str+="${white}"

	# Fill with '-'
	for i in $(seq $temp2 $number)
	do
		str+="-"
	done
	str+="]"
	echo $str
}

boot_bar=$(bar $boot_pcent)
root_bar=$(bar $root_pcent)
home_bar=$(bar $home_pcent)

## Memory

while IFS=":" read -r a b; do
	case $a in
		"MemTotal") ((mem_used+=${b/kB})); mem_total="${b/kB}" ;;
		"Shmem") ((mem_used+=${b/kB}))  ;;
		"MemFree" | "Buffers" | "Cached" | "SReclaimable")
			mem_used="$((mem_used-=${b/kB}))"
		;;
		# Available since Linux 3.14rc (34e431b0ae398fc54ea69ff85ec700722c9da773).
		# If detected this will be used over the above calculation for mem_used.
		"MemAvailable")
			mem_avail=${b/kB}
		;;
	esac
done < /proc/meminfo

if [[ $mem_avail ]]; then
	mem_used=$(((mem_total - mem_avail) / 1024))
else
	mem_used="$((mem_used / 1024))"
fi

mem_total="$((mem_total / 1024))"

mem_perc="$((mem_used * 100 / mem_total))"

mem_used=$(awk '{printf "%.2f", $1 / $2}' <<< "$mem_used 1024")
mem_total=$(awk '{printf "%.2f", $1 / $2}' <<< "$mem_total 1024")
mem_label=GiB

memory="${yellow}${mem_used}${mem_label:-MiB} ${white}/ ${blue}${mem_total}${mem_label:-MiB} ${white}${mem_perc:+(${mem_perc}%)}"

memory_bar="$(bar "${mem_perc}%")"


#########################################
#
#		PROCESSING		
#
#########################################

# Setting updates color 
# if (( $updates_count > 15 )); then
# 	upd_color="${reset}${red}"
# elif (( $updates_count > 5 )); then
# 	upd_color="${reset}${yellow}"
# else
# 	upd_color="${reset}${white}"
# fi

cpu=`cat /proc/cpuinfo | grep "name" | uniq | cut -d ":" -f2 | sed 's/ //;s/(TM)//g;s/(R)//g;s/CPU//;s/  / /'`
proc="${yellow}$PROCESS_ROOT${c1} (r), ${yellow}$PROCESS_USER${c1} (u) | ${yellow}$PROCESS_ALL${c1} (t)"

echo -e "${white}${bold}--------------------------------------------------------------------------------
${c0} ${beg}KERNEL:${c1}${kernel}
${c0} ${beg}UPTIME:${c1}${uptime}
${c0} ${beg}Proc:${c1}${proc}
${c0} ${beg}CPU:${c1}${cpu}
${c0} ${beg}Memory:${memory}
${c0} ${beg}${c1}${memory_bar}
${white}${bold}--------------------------------------------------------------------------------
FILESYSTEM		TOTAL	AVAIL	USED
$root_m			$root_s	$root_a	$root_pcent	${root_bar}
$boot_m			$boot_s	$boot_a	$boot_pcent	${boot_bar}
$home_m			$home_s	$home_a	$home_pcent	${home_bar}
${white}${bold}--------------------------------------------------------------------------------"
教程
#linux #Centos #tool
Centos自定义motd
https://bubao.github.io/posts/c3249d60.html
作者
一念
发布于
2021年9月12日
许可协议