CentOS7.9安全加固镜像制作流程梳理

#!/usr/bin/env bash
# Author:       yuanfan 
# Date:         2021-07-03 
#sec_system.sh 系统加固脚本
export PATH=/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

RGB_DANGER='\033[31;1m'
RGB_WAIT='\033[37;2m'
RGB_SUCCESS='\033[32m'
RGB_WARNING='\033[33;1m'
RGB_INFO='\033[36;1m'
RGB_END='\033[0m'

CHECK_CENTOS=$( cat /etc/redhat-release|sed -r 's/.* ([0-9]+)\..*/\1/' )
CHECK_RAM=$( cat /proc/meminfo | grep "MemTotal" | awk -F" " '{ram=$2/1000000}{printf("%.0f",ram)}' )

LOCK=/var/log/sec_centos7_record.log

tool_info() {
    echo -e "========================================================================================="
    echo -e "                             InitSec CentOS 7 Script                                     "
    echo -e "========================================================================================="
}

check_root(){
    if [[ $EUID -ne 0 ]]; then
        echo -e "${RGB_DANGER}This script must be run as root!${RGB_END}"
        exit 1
    fi
}

check_lock() {
    if [ ! -f "$LOCK" ];then
        touch $LOCK
    else
        echo -e "${RGB_DANGER}Detects that the initialization is complete and does not need to be initialized any further!${RGB_END}"
        exit 1
    fi
}

check_os() {
    if [ "${CHECK_CENTOS}" != '7' ]; then
        echo -e "${RGB_DANGER}This script must be run in CentOS 7!${RGB_END}"
        exit 1
    fi
}

new_swap() {
    echo "============= swap =============" >> ${LOCK} 2>&1
    if [ "${CHECK_RAM}" -le '2' ]; then
    echo -en "${RGB_WAIT}Configuring...${RGB_END}"
    dd if=/dev/zero of=/swapfile bs=1024 count=1048576 >> ${LOCK} 2>&1
    chmod 600 /swapfile >> ${LOCK} 2>&1
    mkswap /swapfile >> ${LOCK} 2>&1
    swapon /swapfile >> ${LOCK} 2>&1
    echo '/swapfile swap swap defaults 0 0' >> /etc/fstab
    echo '# Swap' >> /etc/sysctl.conf
    echo 'vm.swappiness = 10' >> /etc/sysctl.conf
    sysctl -p >> ${LOCK} 2>&1
    sysctl -n vm.swappiness >> ${LOCK} 2>&1
    echo -e "\r${RGB_SUCCESS}Configuration Success${RGB_END}"
    else
    echo -e "${RGB_SUCCESS}Skip, no configuration needed${RGB_END}"
    fi
}

open_bbr() {
    echo "============= bbr =============" >> ${LOCK} 2>&1
    echo -en "${RGB_WAIT}Configuring...${RGB_END}"
    echo "# BBR" >> /etc/sysctl.conf
    echo "net.core.default_qdisc=fq" >> /etc/sysctl.conf
    #echo "net.ipv4.tcp_congestion_control=bbr" >> /etc/sysctl.conf
    sysctl -p >> ${LOCK} 2>&1
    sysctl -n net.ipv4.tcp_congestion_control >> ${LOCK} 2>&1
    lsmod | grep bbr >> ${LOCK} 2>&1
    echo -e "\r${RGB_SUCCESS}Configuration Success${RGB_END}"
}

disable_selinux() {
    echo "============= selinux  =============" >> ${LOCK} 2>&1
    echo -en "${RGB_WAIT}Configuring...${RGB_END}"
    setenforce 0 >> ${LOCK} 2>&1
    sed -i 's/^SELINUX=.*$/SELINUX=disabled/' /etc/selinux/config
    echo -e "\r${RGB_SUCCESS}Configuration Success${RGB_END}"
}

time_zone() {
    echo "============= time zone =============" >> ${LOCK} 2>&1
    echo -en "${RGB_WAIT}Configuring...${RGB_END}"
    rm -rf /etc/localtime >> ${LOCK} 2>&1
    ln -sf /usr/share/zoneinfo/Asia/Shanghai /etc/localtime >> ${LOCK} 2>&1
    ls -ln /etc/localtime >> ${LOCK} 2>&1
    echo -e "\r${RGB_SUCCESS}Configuration Success${RGB_END}"
}

custom_profile() {
    echo "============= custom profile =============" >> ${LOCK} 2>&1
    echo -en "${RGB_WAIT}Configuring...${RGB_END}"
cat > /etc/profile.d/history_command_record.sh  << \EOF
export HISTTIMEFORMAT="[%Y-%m-%d %H:%M:%S] [`who am i 2>/dev/null| awk '{print $NF}'|sed -e 's/[()]//g'`] "
export PROMPT_COMMAND='\
if [ -z "$OLD_PWD" ];then
        export OLD_PWD=$PWD;
fi;
if [ ! -z "$LAST_CMD" ] && [ "$(history 1)" != "$LAST_CMD" ]; then
        logger -t `whoami`_shell_cmd "[$OLD_PWD]$(history 1)";
fi;
export LAST_CMD="$(history 1)";
export OLD_PWD=$PWD;'
export PATH=$PATH:$HISTTIMEFORMAT:$PROMPT_COMMAND
EOF
    cat > /etc/profile.d/centos7custom.sh << EOF
PS1="\[\e[37;40m\][\[\e[32;40m\]\u\[\e[37;40m\]@\h \[\e[35;40m\]\W\[\e[0m\]]\\\\$ "
GREP_OPTIONS="--color=auto"
alias l='ls -AFhlt'
alias grep='grep --color'
alias egrep='egrep --color'
alias fgrep='fgrep --color'
export HISTTIMEFORMAT="%Y-%m-%d %H:%M:%S  "
EOF
    cat /etc/profile.d/centos7custom.sh >> ${LOCK} 2>&1
    echo -e "\r${RGB_SUCCESS}Configuration Success${RGB_END}"
}

adjust_ulimit() {
    echo "============= adjust ulimit =============" >> ${LOCK} 2>&1
    echo -en "${RGB_WAIT}Configuring...${RGB_END}"
    sed -i '/^# End of file/,$d' /etc/security/limits.conf
    cat >> /etc/security/limits.conf <<EOF
# End of file
* soft core unlimited
* hard core unlimited
* soft nproc 1000000
* hard nproc 1000000
* soft nofile 1000000
* hard nofile 1000000
root soft core unlimited
root hard core unlimited
root soft nproc 1000000
root hard nproc 1000000
root soft nofile 1000000
root hard nofile 1000000
EOF
    cat /etc/security/limits.conf >> ${LOCK} 2>&1
    echo -e "\r${RGB_SUCCESS}Configuration Success${RGB_END}"
}