Forum Discussion

Nimbostratus

Jul 25, 2013

Script to check for certificate expiration

Hi guys

Most of you have probably been in the situation where a certificate suddenly expired without anyone noticing (or at least no one took proper action). I was in that situation a couple of weeks ago. I asked Lord Google if someone had a good method of detecting certificate expiration automatically. I didn't really find anything relevant, except for a couple of SOLs from F5 regarding the checkcert utility. So I sat down and did some scripting myself. I'm pretty satisfied with the result, however, this is my first real bash script so you can probably find something that could be optimized or done in a better way.

So first of all the scripts checks if the device is the active box. If it is not, the script does nothing, but if is, the script creates a list of all expiring certificates and places them in expiringcerts.txt. This file is then checked and each line is reported separately to our servicedesk (which in return creates a case and escalates it directly to network operations). When a certificate has been reported it is put in the flaggedcerts.txt. This file ensures that a certificate is not reported multiple times, unless it is less than a week from expiring. In this case a new mail is send each time the script is ran (in our case, it is put in /etc/crontab and configured to run every day at 12 pm/noon).

If a certificate is deleted, expired or renewed it is no longer put in the expiringcerts.txt file and is therefore also removed from the flaggedcerts.txt file.

In the end a status mail is sent to me each day to ensure that the check ran as it should. This is just me that like to be absolutely sure that the script does its job.

___________________________

!/bin/bash

Author: dadalife

Check if unit is active and if it is the script should continue:

ACTIVE=$(tmsh show cm failover-status | grep ACTIVE | wc -l)

if (($ACTIVE == 1)); then

echo -e "Unit is active. Proceeding...\n"

SCRIPTPATH='/root/'

MAIL='servicedesk@atea.dk'

MAILCC='dada@atea.dk'

NUMREPORTED=0

NUMFLAGGED=0

NUMCRITICAL=0

Create a list of all expiring certificates:

tmsh run sys crypto check-cert | grep 'will expired' | awk -F 'in file' '{print $2}' | awk -F ' GMT' '{print $1}' > "$SCRIPTPATH"expiringcerts.txt

echo "A list of all expiring certificates has been created!"

Send an email for each certificate if it has not already been sent:

echo -e "\nChecking for expiring certificates..."

> "$SCRIPTPATH"tempflagged.txt

while read line; do

BODY="\n\nPlease create this case as an incident (Priority 3) under the customer CNM and escalate directly to OPNOM.\n\nThis is an auto-generated e-mail from the BIG-IP."

CERT=$(echo $line | awk -F ' ' '{print $1}')

CERTEXPIRE=$(echo $line | awk -F 'expired on ' '{print $2}')

FLAGGED=$(cat "$SCRIPTPATH"flaggedcerts.txt | grep $CERT | wc -l)

if (( $FLAGGED == 0)); then

echo $CERT >> "$SCRIPTPATH"tempflagged.txt

echo -e "$CERT expires on $CERTEXPIRE GMT.$BODY" | mail -s "$CERT expires on $CERTEXPIRE GMT" $MAIL -c $MAILCC

echo "--> $CERT reported to servicedesk."

NUMREPORTED=$[$NUMREPORTED +1]

else

echo $CERT >> "$SCRIPTPATH"tempflagged.txt

echo "--> $CERT has already been flagged"

NUMFLAGGED=$[$NUMFLAGGED +1]

done < "$SCRIPTPATH"expiringcerts.txt

cp "$SCRIPTPATH"tempflagged.txt "$SCRIPTPATH"flaggedcerts.txt

echo -e "Check for expiring certificates done!"

Check if a certificate is less than a week from expiring:

CURRENTTIMEEPOCH=$(date +%s)

echo -e "\nChecking for almost expired certificates..."

while read line; do

CERTEXPIRE=$(echo $line | awk -F 'expired on ' '{print $2}')

CERTEXPIREEPOCH=$(date --date="$CERTEXPIRE" +%s)

CERTEXPIREDIFF=$(expr $CERTEXPIREEPOCH - $CURRENTTIMEEPOCH)

if (($CERTEXPIREDIFF < 604800)); then

BODY="\n\nPlease create this case as an incident (Priority 1) under the customer CNM and escalate directly to OPNOM.\n\nThis is an auto-generated e-mail from the BIG-IP."

CERT=$(echo $line | awk -F ' ' '{print $1}')

echo -e "$CERT expires on $CERTEXPIRE GMT.$BODY" | mail -s "WARNING: $CERT EXPIRES IN LESS THAN A WEEK!!" $MAIL -c $MAILCC

echo "--> WARNING: $CERT EXPIRES IN LESS THAN A WEEK!!"

NUMCRITICAL=$[$NUMCRITICAL +1]

done < "$SCRIPTPATH"expiringcerts.txt

echo "Check for almost expired certificates done!"

echo -e "\nCertification check done!"

Send a status email:

echo -e "Hi David\n\nYour script did its job!!\n\nNumber of newly reported certificates: '$NUMREPORTED'\nNumber of already flagged certificates: '$NUMFLAGGED'\nNumber of critical certificates: '$NUMCRITICAL'\n\nYours Sincerely\nThe BIG-IP" | mail -s "Everthing went well!" $MAILCC

else

echo "Unit is standby. No action taken!"

___________________

Feel free to comment on anything! :)

Thanks,

David

management

monitoring

hooleylist
Cirrostratus
Aug 12, 2013
Hi David,

Nice work. But could you use checkcert to send an snmptrap or email?

SOL14318: Monitoring SSL certificate expiration on the BIG-IP system (11.x)

SOL3727: Configuring custom SNMP traps

Aaron
R_Eastman_13667
Historic F5 Account
Dec 03, 2013
I was able to use this script in an iApp that I am able to run on a schedule, basically a cron job via the gui.

There is a typo in it. Wherever you see 'will expired' it should be 'will expire'.
- David_Dalgaard_
  Nimbostratus
  Jan 22, 2014
  Hi R Eastman The typo is from the certcheck script that I run to get info about all the certificates. If that typo is fixed in a later release (we run 11.3.0), the script stops working :) I assume this is what happened for you? What version do you run?
- R_Eastman_13667
  Historic F5 Account
  Jan 22, 2014
  11.3.0.
- David_Dalgaard_
  Nimbostratus
  Jan 23, 2014
  Hmm. Same here. Just upgraded to HF8 a couple of hours ago and the typo is still in the "tmsh run sys crypto check-cert". Could be a remnant from an old version. I've seen some funny stuff hiding after upgrade. Our box was origanally in the 9.x branch when first bought, Then 10.x, and finally 11.x before going into production. So we found some scripts that still used Korn shell and similar stuff. But well.. No biggie, just fix the typo so it matches your output :)
miguel_fon_1419
Nimbostratus
May 14, 2014
Thanks a lot for the script.

Very useful!
Paul_73646
Nimbostratus
May 29, 2014
I am getting an error when it tries to mail the data out. here is the error: "send-mail: Cannot open mail:25" I can't seem to figure out why this is happening, does anyone have any ideas on this? Any help would be great!

Héctor_J__Sánc1

Nimbostratus

Sep 16, 2015

Hi,

a little update to check all partitions, not just Common:

!/bin/bash
Author: dadalife


Check if unit is active and if it is the script should continue:
ACTIVE=$(tmsh show cm failover-status | grep ACTIVE | wc -l)
if (($ACTIVE == 1)); then
echo -e "Unit is active. Proceeding...\n"


SCRIPTPATH='/root/'
MAIL=''
MAILCC=''
NUMREPORTED=0
NUMFLAGGED=0
NUMCRITICAL=0

rm -r "$SCRIPTPATH"expiringcerts.txt

Create a list of all expiring certificates:
for PARTITION in $(tmsh -c "cd / ; list sys folder recursive one-line" | awk '{print $3}')
 do 
    tmsh -c "cd /$PARTITION ; run sys crypto check-cert" | grep 'will expired' | awk -F 'in file' '{print $2}' | awk -F ' GMT' '{print $1}' >> "$SCRIPTPATH"expiringcerts.txt
 done
echo "A list of all expiring certificates has been created!"



Send an email for each certificate if it has not already been sent:
echo -e "\nChecking for expiring certificates..."
> "$SCRIPTPATH"tempflagged.txt
while read line; do
       BODY="\n\nIf it was not previously done, please create a Jira for Operations team in order to renew the certificate.\n\nIgnore this
alarm if the certificate is /Common/ca-bundle.crt\n\nThis is an auto-generated e-mail from the BIG-IP."
        CERT=$(echo $line | awk -F ' ' '{print $1}')
        CERTEXPIRE=$(echo $line | awk -F 'expired on ' '{print $2}')
        FLAGGED=$(cat "$SCRIPTPATH"flaggedcerts.txt | grep $CERT | wc -l)
        if (( $FLAGGED == 0)); then
                echo $CERT >> "$SCRIPTPATH"tempflagged.txt
                echo -e "$CERT expires on $CERTEXPIRE GMT.$BODY" | mail -s "$CERT expires on $CERTEXPIRE GMT" $MAIL -c $MAILCC
                echo "--> $CERT reported to servicedesk."
                NUMREPORTED=$[$NUMREPORTED +1]
        else
                echo $CERT >> "$SCRIPTPATH"tempflagged.txt
                echo "--> $CERT has already been flagged"
                NUMFLAGGED=$[$NUMFLAGGED +1]
        fi
done < "$SCRIPTPATH"expiringcerts.txt
cp "$SCRIPTPATH"tempflagged.txt "$SCRIPTPATH"flaggedcerts.txt
echo -e "Check for expiring certificates done!"


Check if a certificate is less than a week from expiring:
CURRENTTIMEEPOCH=$(date +%s)
echo -e "\nChecking for almost expired certificates..."
while read line; do
        CERTEXPIRE=$(echo $line | awk -F 'expired on ' '{print $2}')
        CERTEXPIREEPOCH=$(date --date="$CERTEXPIRE" +%s)
        CERTEXPIREDIFF=$(expr $CERTEXPIREEPOCH - $CURRENTTIMEEPOCH)
        if (($CERTEXPIREDIFF < 604800)); then
                BODY="\n\nIf it was not previously done, please create a Jira for Operations team in order to renew the certificate.\n\nIgnore this 
alarm if the certificate is /Common/ca-bundle.crt\n\nThis is an auto-generated e-mail from the BIG-IP."
                CERT=$(echo $line | awk -F ' ' '{print $1}')
                echo -e "$CERT expires on $CERTEXPIRE GMT.$BODY" | mail -s "WARNING: $CERT EXPIRES IN LESS THAN A WEEK!!" $MAIL -c $MAILCC
                echo "--> WARNING: $CERT EXPIRES IN LESS THAN A WEEK!!"
                NUMCRITICAL=$[$NUMCRITICAL +1]
        fi
done < "$SCRIPTPATH"expiringcerts.txt
echo "Check for almost expired certificates done!"


echo -e "\nCertification check done!"


Send a status email:
echo -e "Hi Miguel\n\nYour script did its job!!\n\nNumber of newly reported certificates: '$NUMREPORTED'\nNumber of already flagged certificates: 
'$NUMFLAGGED'\nNumber of critical certificates: '$NUMCRITICAL'\n\nYours Sincerely\nThe BIG-IP" | mail -s "Everthing went well!" $MAILCC


else
echo "Unit is standby. No action taken!"
fi

Héctor_J__Sánc1

Nimbostratus

Mar 07, 2016

Another update/fix:

!/bin/bash
Author: dadalife

Check if unit is active and if it is the script should continue:
ACTIVE=$(tmsh show cm failover-status | grep ACTIVE | wc -l)
if (($ACTIVE == 1)); then
echo -e "Unit is active. Proceeding...\n"

SCRIPTPATH='/root/'
MAIL=''
MAILCC=''
NUMREPORTED=0
NUMFLAGGED=0
NUMCRITICAL=0
IGNORE=('bundle')

rm -r "$SCRIPTPATH"expiringcerts.txt

Create a list of all expiring certificates:

tmsh -c "cd /; run sys crypto check-cert" | grep 'will expire' | awk -F 'in file' '{print $2}' | awk -F ' GMT' '{print $1}' >> "$SCRIPTPATH"expiringcerts.txt
echo "A list of all expiring certificates has been created!"

Send an email for each certificate if it has not already been sent:
echo -e "\nChecking for expiring certificates..."
> "$SCRIPTPATH"tempflagged.txt
while read line; do

    CERT=$(echo $line | awk -F ' ' '{print $1}')

    for i in "${IGNORE[@]}"
    do
        if [[ "$CERT" == *"$i"* ]]
        then
            echo "Ignoring $CERT"
            continue 2
        fi
    done

    BODY="\n\nIf it was not previously done, please create a Jira for Operations team in order to renew the certificate.\n\nIgnore this
alarm if the certificate is /Common/ca-bundle.crt\n\nThis is an auto-generated e-mail from the BIG-IP."
        CERTEXPIRE=$(echo $line | awk -F 'expired on ' '{print $2}')
        FLAGGED=$(cat "$SCRIPTPATH"flaggedcerts.txt | grep $CERT | wc -l)
        if (( $FLAGGED == 0)); then
                echo $CERT >> "$SCRIPTPATH"tempflagged.txt
                echo -e "$CERT expires on $CERTEXPIRE GMT.$BODY" | mail -s "$CERT expires on $CERTEXPIRE GMT" $MAIL -c $MAILCC
                echo "--> $CERT reported to servicedesk."
                NUMREPORTED=$[$NUMREPORTED +1]
        else
                echo $CERT >> "$SCRIPTPATH"tempflagged.txt
                echo "--> $CERT has already been flagged"
                NUMFLAGGED=$[$NUMFLAGGED +1]
        fi
done < "$SCRIPTPATH"expiringcerts.txt
cp "$SCRIPTPATH"tempflagged.txt "$SCRIPTPATH"flaggedcerts.txt
echo -e "Check for expiring certificates done!"

Check if a certificate is less than a week from expiring:
CURRENTTIMEEPOCH=$(date +%s)
echo -e "\nChecking for almost expired certificates..."
while read line; do

        CERT=$(echo $line | awk -F ' ' '{print $1}')

    for i in "${IGNORE[@]}"
    do
        if [[ "$CERT" == *"$i"* ]]
        then
            echo "Ignoring $CERT"
            continue 2
        fi
    done        

        CERTEXPIRE=$(echo $line | awk -F 'expired on ' '{print $2}')
        CERTEXPIREEPOCH=$(date --date="$CERTEXPIRE" +%s)
        CERTEXPIREDIFF=$(expr $CERTEXPIREEPOCH - $CURRENTTIMEEPOCH)
        if (($CERTEXPIREDIFF < 604800)); then
                BODY="\n\nIf it was not previously done, please create a Jira for Operations team in order to renew the certificate.\n\nIgnore this 
alarm if the certificate is /Common/ca-bundle.crt\n\nThis is an auto-generated e-mail from the BIG-IP."
                echo -e "$CERT expires on $CERTEXPIRE GMT.$BODY" | mail -s "WARNING: $CERT EXPIRES IN LESS THAN A WEEK!!" $MAIL -c $MAILCC
                echo "--> WARNING: $CERT EXPIRES IN LESS THAN A WEEK!!"
                NUMCRITICAL=$[$NUMCRITICAL +1]
        fi
done < "$SCRIPTPATH"expiringcerts.txt
echo "Check for almost expired certificates done!"

echo -e "\nCertification check done!"

Send a status email:
echo -e "Hi Héctor\n\nYour script did its job!!\n\nNumber of newly reported certificates: '$NUMREPORTED'\nNumber of already flagged certificates: 
'$NUMFLAGGED'\nNumber of critical certificates: '$NUMCRITICAL'\n\nYours Sincerely\nThe BIG-IP" | mail -s "Everthing went well!" $MAILCC

else
echo "Unit is standby. No action taken!"
fi

Had to change grep 'will expired' to grep 'will expire', and now you can ignore certs to reduce the noise. Also removed the partition loop, you can check all certs from root dir.

Héctor_J__Sánc1

Nimbostratus

Mar 07, 2016

Another update/fix:

!/bin/bash
Author: dadalife

Check if unit is active and if it is the script should continue:
ACTIVE=$(tmsh show cm failover-status | grep ACTIVE | wc -l)
if (($ACTIVE == 1)); then
echo -e "Unit is active. Proceeding...\n"

SCRIPTPATH='/root/'
MAIL=''
MAILCC=''
NUMREPORTED=0
NUMFLAGGED=0
NUMCRITICAL=0
IGNORE=('bundle')

rm -r "$SCRIPTPATH"expiringcerts.txt

Create a list of all expiring certificates:

tmsh -c "cd /; run sys crypto check-cert" | grep 'will expire' | awk -F 'in file' '{print $2}' | awk -F ' GMT' '{print $1}' >> "$SCRIPTPATH"expiringcerts.txt
echo "A list of all expiring certificates has been created!"

Send an email for each certificate if it has not already been sent:
echo -e "\nChecking for expiring certificates..."
> "$SCRIPTPATH"tempflagged.txt
while read line; do

    CERT=$(echo $line | awk -F ' ' '{print $1}')

    for i in "${IGNORE[@]}"
    do
        if [[ "$CERT" == *"$i"* ]]
        then
            echo "Ignoring $CERT"
            continue 2
        fi
    done

    BODY="\n\nIf it was not previously done, please create a Jira for Operations team in order to renew the certificate.\n\nIgnore this
alarm if the certificate is /Common/ca-bundle.crt\n\nThis is an auto-generated e-mail from the BIG-IP."
        CERTEXPIRE=$(echo $line | awk -F 'expired on ' '{print $2}')
        FLAGGED=$(cat "$SCRIPTPATH"flaggedcerts.txt | grep $CERT | wc -l)
        if (( $FLAGGED == 0)); then
                echo $CERT >> "$SCRIPTPATH"tempflagged.txt
                echo -e "$CERT expires on $CERTEXPIRE GMT.$BODY" | mail -s "$CERT expires on $CERTEXPIRE GMT" $MAIL -c $MAILCC
                echo "--> $CERT reported to servicedesk."
                NUMREPORTED=$[$NUMREPORTED +1]
        else
                echo $CERT >> "$SCRIPTPATH"tempflagged.txt
                echo "--> $CERT has already been flagged"
                NUMFLAGGED=$[$NUMFLAGGED +1]
        fi
done < "$SCRIPTPATH"expiringcerts.txt
cp "$SCRIPTPATH"tempflagged.txt "$SCRIPTPATH"flaggedcerts.txt
echo -e "Check for expiring certificates done!"

Check if a certificate is less than a week from expiring:
CURRENTTIMEEPOCH=$(date +%s)
echo -e "\nChecking for almost expired certificates..."
while read line; do

        CERT=$(echo $line | awk -F ' ' '{print $1}')

    for i in "${IGNORE[@]}"
    do
        if [[ "$CERT" == *"$i"* ]]
        then
            echo "Ignoring $CERT"
            continue 2
        fi
    done        

        CERTEXPIRE=$(echo $line | awk -F 'expired on ' '{print $2}')
        CERTEXPIREEPOCH=$(date --date="$CERTEXPIRE" +%s)
        CERTEXPIREDIFF=$(expr $CERTEXPIREEPOCH - $CURRENTTIMEEPOCH)
        if (($CERTEXPIREDIFF < 604800)); then
                BODY="\n\nIf it was not previously done, please create a Jira for Operations team in order to renew the certificate.\n\nIgnore this 
alarm if the certificate is /Common/ca-bundle.crt\n\nThis is an auto-generated e-mail from the BIG-IP."
                echo -e "$CERT expires on $CERTEXPIRE GMT.$BODY" | mail -s "WARNING: $CERT EXPIRES IN LESS THAN A WEEK!!" $MAIL -c $MAILCC
                echo "--> WARNING: $CERT EXPIRES IN LESS THAN A WEEK!!"
                NUMCRITICAL=$[$NUMCRITICAL +1]
        fi
done < "$SCRIPTPATH"expiringcerts.txt
echo "Check for almost expired certificates done!"

echo -e "\nCertification check done!"

Send a status email:
echo -e "Hi H&233;ctor\n\nYour script did its job!!\n\nNumber of newly reported certificates: '$NUMREPORTED'\nNumber of already flagged certificates: 
'$NUMFLAGGED'\nNumber of critical certificates: '$NUMCRITICAL'\n\nYours Sincerely\nThe BIG-IP" | mail -s "Everthing went well!" $MAILCC

else
echo "Unit is standby. No action taken!"
fi

Had to change grep 'will expired' to _grep 'will expire'_, and now you can ignore certs to reduce the noise. Also removed the partition loop, you can check all certs from root dir.

psxg_345884
Nimbostratus
Jan 11, 2018
Hello,

I tried this script and I did some mods to it. However, I am getting the email body as follows:

/Common/appnet-test.crt expires on GMT.

Not sure why it shows "GMT" rather than the actual expiration date.

Please help.

Thank you
REastman_249266
Historic F5 Account
Jan 11, 2018
psxg,

I would check your variable syntax for this line CERTEXPIRE=$(echo $line | awk -F 'expired on ' '{print $2}') you may have a typo. It sounds like the CERTEXPIRE variable isn't been set.

psxg_345884

Nimbostratus

Jan 11, 2018

I have:

CERTEXPIRE=$(echo $line | awk -F 'expired on ''{print $2}')
    CERTEXPIREEPOCH=$(date --date="$CERTEXPIRE" +%s)
    CERTEXPIREDIFF=$(expr $CERTEXPIREEPOCH - $CURRENTTIMEEPOCH)

if (($CERTEXPIREDIFF < 2419200)); then
            BODY="\n\nIf it was not previously done, please create a Service Now Ticket for Systems team in order to renew the certificate.\n\nIgnore this
alarm if the certificate is /Common/ca-bundle.crt\n\nThis is an auto-generated e-mail from the BIG-IP."
            echo -e "$CERT expires on $CERTEXPIRE GMT.$BODY" | mail -s "WARNING: $CERT EXPIRES IN LESS THAN A MONTH!!" $MAIL -c $MAILCC
            echo "--> WARNING: $CERT EXPIRES IN LESS THAN A MONTH!!"
            NUMCRITICAL=$[$NUMCRITICAL +1]
    fi

I see it declared just fine. Is "$CERTEXPIRE GMT.$BODY"" correct ?

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