mjhjmtu

I was tasked to do a bash script that can audit logins in mysql.


If you activate the general_log option in /etc/my.cnf, you can register all the activity that mysql does and it get write (in my case) in /var/lib/mysql/localhost.log.
If i cat it, i get this line:

2018-11-18T12:39:46.622298Z 5 Connect Access denied for user 'root'@'localhost' (using password: YES)

So, with that in mind, I made this grep syntax (change the variables to actual numbers and it works!):

grep "$year"-"$month"-"$day" /var/lib/mysql/localhost.log | grep Connect | grep -v denied

grep "$year"-"$month"-"$day" /var/lib/mysql/localhost.log | grep Connect | grep denied

I also made a grep instruction that counts how many of these logins are made.

grep "$year"-"$month"-"$day" /var/lib/mysql/localhost.log | grep Connect | grep -cv denied

grep "$year"-"$month"-"$day" /var/lib/mysql/localhost.log | grep Connect | grep -c denied

They all work and, AFAIK they are technically correct (spellchecked!).

But I need to bake them into a script so I can take variables from the user and put them into a proper script, but I can't make them work so far: I'm getting the error you can see below when bash tries to read the first variable.

The code so far:

#!/bin/bash
echo "Year input: "
read -r year
 if [[ $year -gt 2020 ]];
 then
 echo "Incorrect year input."
 exit 1
 else
 echo "Month input: "
 read -r month
 if [[ $month -gt 12 ]];
 then
 echo "Incorrect month input."
 exit 1
 else
 echo "Day input: "
 read -r day
 if [[ $day -gt 31 ]];
 then
 echo "Incorrect day input."
 exit 1
 else
 grep "$year"-"$month"-"$day" /var/lib/mysql/localhost.log | grep Connect | grep -v denied
 logbien=$(grep "$year"-"$month"-"$day" /var/lib/mysql/localhost.log | grep Connect | grep -cv denied)
 echo "Correct logins: "echo "$logbien" | wc -1 " times."
 echo ''
 grep "$year"-"$month"-"$day" /var/lib/mysql/localhost.log | grep Connect | grep denied
 logmal=$(grep "$year"-"$month"-"$day" /var/lib/mysql/localhost.log | grep Connect | grep -c denied)
 echo "Incorrect logins: "echo "$logmal" | wc -1 " times."
 fi
 fi
 fi
exit 0

The error I get (original: image 1 below):

[root@localhost ~]# sh /medla/sf_compartida/two.sh
Year input:
2018
': not a valid identifiersh: line 3: read: `year
/media/sf_compartida/two.s: line 34: syntax error: unexpected end of file
[root@localhost ~]#

Edit

New code:

#!/bin/bash
read -r -p "Enter the date (YYYY-mm-dd): " date
if ! date=$(date -d "$date" "+%Y-%m-%d")
 then
 echo "Error: invalid date" >&2
 exit 1
fi
year=$date%%-*
if [[ $year -gt 2020 ]]
 then 
 echo "invalid year" >&2
 exit 1
 else
 grep "$date" /var/lib/mysql/localhost.log | grep Connect | grep -v denied
 logbien=$(grep "$date" /var/lib/mysql/localhost.log | grep Connect | grep -cv denied)
 echo "Correct logins: "echo "$logbien" | wc -1" times."
 echo ''
 grep "$date" /var/lib/mysql/localhost.log | grep Connect | grep denied
 logmal=$(grep "$date" /var/lib/mysql/localhost.log | grep Connect | grep -c denied)
 echo "Incorrect logins: "echo "$logmal" | wc -1" times."
fi

The error I get (original: image 2 below):

[root@localhost ~]# sh /media/sf_compartida/two2.sh
Enter the date (YYYY-mm-dd): 2018-11-20
': not a valid identifier.sh: line 2: read: `date
/media/sf compartida/two2.sh: line 9: syntax error in conditional expression
'media/sf_compartida/two2.sh: line 9: syntax error near `]]
'media/sf_compartida/two2.sh: line 9: `if [[ $year -gt 2020 ]]
[root@localhost ~]#

Error 1 - image:

Error 2 - image:

This is not an answer, but a bit of code review: I would offer this to improve your date entry: get the user to enter the date at once, and use the date command to validate and normalize the user's input.

read -r -p "Enter the date (YYYY-mm-dd): " date
if ! date=$(date -d "$date" "+%Y-%m-%d"); then
 echo "Error: invalid date" >&2
 exit 1
fi
year=$date%%-*
if [[ $year -gt 2020 ]]; then echo "invalid year" >&2; exit 1; fi

# then: grep "$date" logfile ...