• Comments
  • Updated 2021.07.16 FIPS implementation script for RHEL/CentOS 7 and 8 (gitlab added 2020.01.08)

    Posted on

    I made a script to implement FIPS 140-2 compliance based on what I found at https://access.redhat.com/solutions/137833. I think Red-Hatter Ryan Sawhill put that solution together.

    Dusan Baljevic contribued as well with various aspects of this (hat tip).

    Added RHEL 8 method 2020.01.20 (scroll down)

    Added gitlab repo 2020.01.08

    https://gitlab.com/rhelrj/enablefips

    added 2019.06.05

    By the way, for those of you who need efi/uefi partition, use this in your kickstart:

    part /boot/efi --fstype="vfat" --size=5100
    

    Yeah, the 5100 is overkill, I'm good with that.

    • I have initially used
      uname -r
      to detect the version of Linux (i.e. 7).
    • I did not use /etc/redhat-release as part of a conditional test because I have seen too many admins in various environments malign/edit /etc/redhat-release file for a number of reasons, so I personally can not trust the integrity of that file, and shall opt for a less-fragile method
    • Hoever, I may transition this to an rpm check for
      redhat-release-server
      however, we use this script for both rhel 7.x workstation & server.
    • This has been tested on CentOS 7 and works.
      I realize the script can certainly be improved on.

    Also, if anyone believes this script misses anything, I welcome feedback

    Thanks Dusan Baljevic for finding errant typos and testing on UEFI systems (8/24/2018)

    Regards,

    -RJ

    RHEL 8 Method (RHEL 7 follows)

    This comes from this link

    # echo "this is for RHEL 8/CentOS 8"
    # fips-mode-setup --enable
    Setting system policy to FIPS
    FIPS mode will be enabled.
    Please reboot the system for the setting to take effect.
    

    RHEL 7 method follows

    #!/bin/bash
    #
    # 7/16/2021 Dusan Baljevic provided some very good updates which this edition has below.  Namely, adding RHEL/CentOS 8 (and it's varieties).  
    # There is a previous edition at discussion https://access.redhat.com/discussions/3487481 which has an uninstall routine (Thanks Dusan).
    # To uninstall fips on RHEL/Cent 7, you'd just remove dracut-fips and eliminate the fips=1 directives in /etc/default/grub and do a grub2-mkconfig.
    # RHEL/Cent 8 is different in removing fips and we may include that at a later time.  
    
    # 10/17/2018 changed uname directives to use "uname -r" which works better in some environments.  Additionally ensured quotes were paired (some were not in echo statements)
    #
    # this script was posted originally at https://access.redhat.com/discussions/3487481 and the most current edition is most likely (maybe) posted there... maybe.  
    # updated 8/24/2018 (thanks for those who  provided inputs for update)
    # 
    # Purpose, implement FIPS 140-2 compliance using the below article as a reference
    # See Red Hat Article https://access.redhat.com/solutions/137833
    ##   --  I suspect Red-Hatter Ryan Sawhill https://access.redhat.com/user/2025843 put that solution together (Thanks Ryan).
    # see original article, consider "yum install dracut-fips-aesni"
    # --> And special thanks to Dusan Baljevic who identified typos and tested this on UEFI
    # NOTE: You can create a Red Hat Login for free if you are a developer, 
    # - Go to access.redhat.com make an account and then sign into 
    # - developers.redhat.com with the same credentials and then check your email and accept the Developer's agreement.
    # Risks...  1) Make sure ${mygrub} (defined in script) is backed up as expected and the directives are in place prior to reboot
    # Risks...  2) Make sure /etc/default/grub is backed up as expected and the proper directives are in place prior to reboot
    # Risks...  3) Check AFTER the next kernel upgrade to make sure the ${mygrub} (defined in script) is properly populated with directives
    # Risks...  4) Be warned that some server roles either do not work with FIPS enabled (like a Satellite Server) or of other issues, and you've done your research
    # Risks...  5) There are more risks, use of this script is at your own risk and without any warranty
    # Risks...  6) The above list of risks is -not- exhaustive and you might have other issues, use at your own risk.
    # Recommend using either tmux or screen session if you are using a remote session, in case your client gets disconnected. 
    #
    
    ##### Where I found most of the directives... some was through my own pain with the cross of having to do stig compliance.
    rhsolution="https://access.redhat.com/solutions/137833"
    manualreview="Please manually perform the steps found at $rhsolution"
    
    ####### check if root is running this script, and bail if not root
    # be root or exit
    if [ "$EUID" -ne 0 ]; then
       echo -e "\tPlease run as root"
       exit 1
    fi
    
    ## Dusan's suggestion...
    myrhelcheck="$(rpm -qa --queryformat '%{VERSION}\n' '(redhat|sl|slf|centos|oraclelinux)-release(|-server|-workstation|-client|-computenode)')"
    
    ##### and bail if it is not RHEL 7 or 8
    if [ "$(echo $myrhelcheck | egrep "^7|^8")" = "" ] ; then
       echo "\n\tScript is intended for RHEL 7 and 8 systems only, bailing...\n"
       exit 1
    fi
    
    ## Dusan's suggestion...
    echo -e "\n\tFIPS-140-2 Validation\n"
    echo -e "\tChecking Linux Kernel parameters of currently booted system\n"
    CMDLINE=$(cat /proc/cmdline)
    if [ "$(echo $CMDLINE | egrep "fips=1")" = "" ]
    then
       echo -e "\tFIPS is not enabled in kernel (fips=1)\n"
    else
       echo -e "\tFIPS is enabled in kernel (fips=1)\n"
    fi
    
    ## Dusan's suggestion...
    FIPSCK="$(fipscheck 2>/dev/null)"
    if [ "$FIPSCK" != "" ]
    then
       if [ "$(echo $FIPSCK | grep -i off)" != "" ]
       then
          echo -e "\tFIPS is not enabled (verified by fipscheck)\n"
       else
          echo -e "\tFIPS is already enabled (verified by fipscheck)\n"
          exit 0
       fi
    else
       answer=`sysctl crypto.fips_enabled`
       yes="crypto.fips_enabled = 1"
       configured="The sysctl crypto.fips_enabled command has detected FIPS is already configured, bailing..."
       notconfigured="FIPS not currently activated, so proceeding with script."
    
       if [ "$answer" == "$yes" ] ; then
          echo -e "\tFIPS is already enabled (verified by sysctl)\n"
          exit 0
       else
          echo -e "\tFIPS is not enabled (verified by sysctl)\n"
       fi
    fi
    
    ## Dusan's suggestion...
    if [[ "$myrhelcheck" =~ ^8.* ]]
    then
       echo -e "\n\tRHEL 8 detected"
       echo -e "\tEnabling FIPS mode"
       fips-mode-setup --enable 
       echo -e "\n\tScript has completed.\n\t--AFTER--REBOOT--as-root-- run fipscheck\n"
       exit 0
    fi
    
    echo -e "\n\tRHEL 7 detected"
    echo -e "\tEnabling FIPS mode"
    
    ##### uefi check, bail if uefi (I do not have a configured uefi system to test this on)
    ######- Added 7/5/2018, do not proceed if this is a UEFI system... until we can test it reliably
    [ -d /sys/firmware/efi ] && fw="UEFI" || fw="BIOS"
    echo -e "$fw"
    if [ "$fw" == "UEFI" ] ; then
       echo -e "\n\tUEFI detected, this is a ($fw) system.\n\setting \$fw variable to ($fw)..."
       mygrub='/boot/efi/EFI/redhat/grub.cfg'  
       ### Thanks Dusan Baljevic for testing this.  
       ### exit 1
    else
       echo -e "\n\t($fw) system detected, proceeding...\n"
       mygrub='/boot/grub2/grub.cfg'
    fi
    
    ######- add a second to $mydate variable
    sleep 1
    mydate=`date '+%Y%m%d_%H_%M_%S'`;echo $mydate
    
    ##### make backup copy $mygrub defined earlier
    cp -v ${mygrub}{,.$mydate}
    
    ##### check fips in grub, if it's there, bail, if not proceed
    myfipscheckingrub=`grep fips $mygrub | grep linux16 | egrep -v \# | head -1`
    if [ "$myfipscheckingrub" != "" ] ; then
       echo -e "FIPS directives detected in ($mygrub), \n\t\t($myfipscheckingrub)\n\tSo, recommend AGAINST running this script\n\t$manualreview"
       exit 1
    else
       echo -e "\n\tFIPS directives not detected in ($mygrub)\n\tproceeding..."
    fi
    
    ##### fips should not be in /etc/default/grub, if so, bail
    etcdefgrub='/etc/default/grub'
    myfipschecketcdefgrub=`grep fips $etcdefgrub | grep -v \#`
    if [ "$myfipschecketcdefgrub" != "" ] ; then
       echo -e "FIPS directives detected in ($etcdefgrub), \n\t\t($myfipschecketcdefgrub)\n\tSo, recommend AGAINST running this script\n\t$manualreview"
       echo exit 1
    else
       echo -e "\n\tFIPS directives not detected in ($etcdefgrub)\n\tproceeding..."
    fi
    
    ##### verify that this system is actually in the same kernel as we're going to install this in..., or bail
    # if they don't match, the script bails.
    mydefkern=`grubby --default-kernel | sed 's/.*vmlinuz\-//g'| awk '{print $1}'`
    myuname=`uname -r`
    if [ "$mydefkern" != "$myuname" ] ; then
       echo -e "\n\tKernel Mismatch between running and installed kernel...\n\tThe default kernel is: $mydefkern\n\tThe running kernel is $myuname\n\n\tPlease reboot this system and then re-run this script\n\tBailing...\n"
       exit 1
    else
     echo "Default Kernel ($mydefkern) and Current Running Kernel ($myuname) match, proceeding"
    fi
    
    ##### overkill, yes
    # yes, there's an number of checks above, but I'm still persisting with this, just in case someone runs this script twice.  
    # it will never reach this if it fails any of the previous checks, but I'll leave it.
    #####  a file named "/root/fipsinstalled" is created at the end of this script.  So I'll check for it at the beginning so that this script is only ran once.
    if [ -f /root/fipsinstalled ] ; then
       sysctl crypto.fips_enabled
       echo -e "\tThis script was ran previously,\n\t nothing to do, \n\texiting..."
       exit 1
    else
       echo "continuing" >/dev/null
       echo proceeding...
    fi
    ############################################################################################
    ############################################################################################
    ############################################################################################
    
    ##### this is where the script actually begins to make modifications.  
    # -- everything before was either a check, or a backup of a config
    # Only install dracut-fips if it is not installed (that's the "||" below)
    rpm -q dracut-fips > /dev/null || yum -y install dracut-fips
    
    if [ "$(egrep -qw aes /proc/cpuinfo && echo YES || echo no)" == "YES" ]; then
       yum -y install dracut-fips-aesni
    fi
    
    ##### warn people not to bail at this point, pause 4 seconds so they might see it if they're watching the screen.
    echo -e "\n\n\n\tWARNING!!!: \n\tWARNING!!!DO NOT INTERRUPT THIS SCRIPT OR IT CAN CAUSE \n\tTHE SYSTEM TO BECOME UNBOOTABLE!!!!\n\tPlease be patient it will take some time...\n\tWARNING!!!\n\tWARNING\n\n\n"
    sleep 4
    ##### next disable prelinking
    rpm -q prelink >/dev/null && grep PRELINKING /etc/sysconfig/prelink 
    
    ##### slightly lesser known use of sed, it only flips PRELINKING to "no"
    # this flips "yes" to "no" in the prelink config file, next kills prelinking
    rpm -q prelink >/dev/null && sed -i '/^PRELINKING/s,yes,no,' /etc/sysconfig/prelink
    rpm -q prelink >/dev/null && prelink -uav 2>/tmp/err
    /bin/cp -v /etc/aide.conf{,.undofips}
    rpm -q prelink >/dev/null && sed -i 's/^NORMAL.*/NORMAL = FIPSR+sha512/' /etc/aide.conf
    
    ##### update the $mydate variable which is used to copy off backups of various configs throughout the rest of this script.
    mydate=`date '+%Y%m%d_%H_%M_%S'`;echo $mydate
    
    ###-----###
    # back up existing initramfs
    mv -v /boot/initramfs-$(uname -r).img{,.$mydate}
    
    ##### warn people not to bail at this point, pause 4 seconds so they might see it if they're watching the screen.
    ##### really, don't interrupt this portion.
    echo -e "\n\n\n\tWARNING!!!: \n\tWARNING!!!DO NOT INTERRUPT THIS SCRIPT OR IT CAN CAUSE \n\tTHE SYSTEM TO BECOME UNBOOTABLE!!!!\n\tPlease be patient it will take some time...\n\tWARNING!!!\n\tWARNING!!!\n\n\n"
    # this pauses as before so the person running this script gets a chance to see the above, it also is to allow the $mydate variable below to get a new value
    sleep 3
    # run dracut
    dracut
    mydate=`date '+%Y%m%d_%H_%M_%S'`
    ###-----###
    
    ###### The Red Hat solution I cited earlier in the comments, this is where this came from
    # this section below updates /boot/grub/grub.cfg with fips and the uuid of the boot device
    # first back it up
    /bin/cp ${mygrub}{,.$mydate}
    grubby --update-kernel=$(grubby --default-kernel) --args=fips=1
    
    ###### this displays the kernel lines in grub with fips
    grep fips ${mygrub} | grep linux16
    
    ###### that Red Hat solution I cited earlier in the comments, this is where this came from
    # set the uuid variable to be used later
    uuid=$(findmnt -no uuid /boot)
    echo -e "\n\t Just for reference, the /boot uuid is: ($uuid)\n"
    
    ###### that Red Hat solution I cited earlier in the comments, this is where this came from
    # update  the boot uuid for fips in ${mygrub}
    # the 2nd line is to satisfy the disa stig checker which checks every single menu entry linux16 line.  without it, the check fails.
    [[ -n $uuid ]] && grubby --update-kernel=$(grubby --default-kernel) --args=boot=UUID=${uuid}
    # update 7/23/2019.  The next line is excessive.  The impact of the next line, when the system goes to emergency mode, and you select **any** kernel at grub, you are faced with a system that **will not** accept any password.  I've removed it for the rescue kernel.
    ## so maybe your security people require this. **IF** the do, then know that when you go to emergency mode, you **will** require the grub password (know it in advance!) and you ought to set **one time only** the grub line to fips=0 **for a one time only boot**
    # 
    #sed -i "/linux16 \/vmlinuz-0-rescue/ s/$/ fips=1 boot=UUID=${uuid}/"  ${mygrub}
    
    ###### that Red Hat solution I cited earlier in the comments, this is where this came from
    # update /etc/default/grub for subsequent kernel updates. this APPENDS to the end of the line.  
    sed -i "/^GRUB_CMDLINE_LINUX/ s/\"$/  fips=1 boot=UUID=${uuid}\"/" /etc/default/grub
    grep -q GRUB_CMDLINE_LINUX_DEFAULT /etc/default/grub || echo 'GRUB_CMDLINE_LINUX_DEFAULT="fips=1"' >> /etc/default/grub
    echo -e "\n\tThe next line shows the new grub line with fips in the two locations below:\n"
    grep $uuid ${mygrub} | grep linux16
    echo;grep $uuid /etc/default/grub
    
    ### warning ### warning ###
    ### Note, if you do not change Ciphers and MACs prior to reboot, you will NOT be able to ssh to the system.  That could be a problem depending on the distance or difficulty of getting a console or physical access to fix after reboot.  Be warned.
    ###
    mydate=`date '+%Y%m%d_%H_%M_%S'`;echo $mydate
    cp -v /etc/ssh/sshd_config{,.$mydate}
    
    # without this, no ssh, really, ask me how I know
    sed -i 's/^Cipher.*/Ciphers aes128-ctr,aes192-ctr,aes256-ctr/' /etc/ssh/sshd_config
    sed -i 's/^MACs.*/MACs hmac-sha2-256,hmac-sha2-512/' /etc/ssh/sshd_config
    
    # bread crumbs
    touch /root/fipsinstalled
    chattr +i /root/fipsinstalled
    
    ###### the command to check this after reboot is: sysctl crypto.fips_enabled
    echo -e "\n\tScript has completed.  \n\tSystem must be rebooted for fips to be enabled.  \n\tPlease check the following 2 files for sane entries:\n\t/etc/default/grub \n\t${mygrub}.  \n\n\tAlso, --AFTER--REBOOT--as-root-- run sysctl crypto.fips_enabled and the output must be \n\t'crypto.fips_enabled = 1' \n"
    
    ##### without this, the disa provided stig checker fails fips compliance, you're welcome
    rpm -q prelink > /dev/null && rpm -e prelink > /dev/null
    ##### Same with this...
    /bin/chmod 0600 /etc/ssh/ssh_host*key
    
    exit 0
    
    
    

    Last update 2021.07.16

    by

    points

    Responses

    Red Hat
    © 2025 Red Hat, Inc.