comparing string to a text file with if statement

[treyhunsucker]

Hello,

I am working on a script that will check to verify the md5 of a file hasn't changed. Here is what I have so far:

#!/usr/bin/perl

if ($md5 eq "@my_file") {
print "Secure";
} else {
print "Unsecure";
}

$md5 = 'MD5 (/etc/pf.conf) = d813f6767fd31ce8cb075cad145da694';

open (FILE, "/var/apps/scripts/security/results") or die "cannot open file: $!";
flock(FILE, 2) or die "cannot lock file: $!";

@my_file = <FILE>;

The problem I am running into is that even if I change $md5 to $md5 = 'test' then it still prints "Secure".

Any help would be greatly appreciated.

 

[ishnid]

It seems to me like you're declaring your $md5 and @my_file variables after you're checking if they're the same. At the time you run your "if" statement, both $md5 and "@my_file" will evaluate to empty strings in that context, so they'll be the same and "Secure" will be printed.

I'd strongly advise enabling strict checking and warnings, so that perl will automatically alert you to issues such as this.

 

[treyhunsucker]

Ok, thank you for the suggestions.

I enabled warnings and strict checking which helped me debug a lot.

I decided to simply my scripts for testing and then move to what I want.

This works with no errors so I know my syntax and etc. are correct
========================================
#!/usr/bin/perl -w

use strict;

my $md5 = '12345';
my $check = '12345';

if ($md5 eq $check) {
print "Secure";
} else {
print "Unsecure";
}
=========================================


This does not work, it does not give any errors, just always prints Unsecure. The "results" file and $md5 are equal to each other, I also set the permissions to both the script and the txt file to 755
===========================================
#!/usr/bin/perl -w

use strict;

my $md5 = '12345';
my $check = '@my_file';

open (FILE, "/var/apps/scripts/security/results") or die "cannot open file: $!";
flock(FILE, 2) or die "cannot lock file: $!";

my @my_file = <FILE>;

if ($md5 eq @my_file) {
print "Secure";
} else {
print "Unsecure";
}
===================================================

I do not think that opening the text file is the way to go, I would like to be able to just run a script that checks md5 of /etc/pf.conf and then does the if statement.

I wrote a script like I wanted but it prints out whats below, and then the script is below it.
######################################################
MD5 (/etc/pf.conf) = d813f6767fd31ce8cb075cad145da694
Unsecure
######################################################
====================================================
#!/usr/bin/perl -w

use strict;

#my $check = 'system("/sbin/md5 /etc/pf.conf")';
my $md5 = 'MD5 (/etc/pf.conf) = d813f6767fd31ce8cb075cad145da694';
my @check = system("/sbin/md5 /etc/pf.conf");

if ($md5 eq @check) {
print "Secure";
} else {
print "Unsecure";
}
====================================================

As you can see I don't know how to put the results into the script so that the if statement will work properly. Any ideas are greatly appreciated.

 

[ishnid]

if ($md5 eq @my_file) {

You're using an array in a scalar context there, where it will return the number of elements in the array, not the contents of the elements themselves.

 

[treyhunsucker]

Yes you are correct, when put in a print @check then it prints "0"

Can you point me in the right direction? I'm been googling and searching but I just can't seem to find anything and I feel like I'm looking for the wrong thing in the wrong direction.

 

[KevinADC]

all this does is returns the exit status of the program:

my @check = system("/sbin/md5 /etc/pf.conf");

if you need the output of the program, try this:

my @check = qx|/sbin/md5 /etc/pf.conf|;

but that should probably be a scalar and not an array:

my $check = qx|/sbin/md5 /etc/pf.conf|;

------------------------------------------
- Kevin, perl coder unexceptional!

 

[treyhunsucker]

TYVM Kevin, I am a lot closer now.

Here is my current script
=======================
#!/usr/bin/perl -w

use strict;

my $md5 = 'MD5 (/etc/pf.conf) = d813f6767fd31ce8cb075cad145da694';
my $check = qx|/sbin/md5 /etc/pf.conf|;

if ($md5 eq $check) {
print "Secure\n";
} else {
print "Unsecure\n";
}

print "$check\n";
print "$md5\n";
======================

Here is the output
======================
server# perl 1.pl
Unsecure
MD5 (/etc/pf.conf) = d813f6767fd31ce8cb075cad145da694

MD5 (/etc/pf.conf) = d813f6767fd31ce8cb075cad145da694
======================

The IF statement still doesn't see $md5 and $check as the same, what am I missing?

 

[RodKnowlton]

Your missing the newline on $md5. See how $check has and extra newline when you print it out?

- Rod



IBM Certified Advanced Technical Expert pSeries and AIX 5L
CompTIA Linux+
CompTIA Security+

Wish you could view posts with a fixed font? Got Firefox & Greasemonkey? Give yourself the option.

 

[RodKnowlton]

s/and/an/;

- Rod

 

[KevinADC]

try chomp()-ing $check before checking it:

my $check = qx|/sbin/md5 /etc/pf.conf|;
chomp($check);

judging by the output you posted there is a newline on the end.



------------------------------------------
- Kevin, perl coder unexceptional!

 

[treyhunsucker]

Ok I added chomp and this is what I got:


server# perl 1.pl
Unsecure
MD5 (/etc/pf.conf) = d813f6767fd31ce8cb075cad145da694
MD5 (/etc/pf.conf) = d813f6767fd31ce8cb075cad145da694


I didn't Understand what you meant by "s/and/an/;" Rod

BTW, how are you doing the code box?

 

[KevinADC]

code box (see the "Process TGML" link just below the box where you neter posts).

[ignore]

your code here

[/ignore]

these visually look the same:

MD5 (/etc/pf.conf) = d813f6767fd31ce8cb075cad145da694
MD5 (/etc/pf.conf) = d813f6767fd31ce8cb075cad145da694

but there must be something different, possibly the number of spaces between "words". If that is not important try this:

#!/usr/bin/perl -w

use strict;

my $md5 = 'MD5 (/etc/pf.conf) = d813f6767fd31ce8cb075cad145da694';
my $check = qx|/sbin/md5 /etc/pf.conf|;
chomp($check);
#remove all spaces
$md5 =~ s/\s//g;
$check =~ s/\s//g;


if ($md5 eq $check) {
        print "Secure\n";
} else {
        print "Unsecure\n";
}

print "$check\n";
print "$md5\n";

------------------------------------------
- Kevin, perl coder unexceptional!

 

[RodKnowlton]

treyhunsucker,

I meant "substitute 'an' for 'and' in the previous post" (my fingers had decided to type a different word than I meant ).

Click on "Process TGML" below the posting box to see the various markup items available, including the code box.

- Rod


IBM Certified Advanced Technical Expert pSeries and AIX 5L
CompTIA Linux+
CompTIA Security+

Wish you could view posts with a fixed font? Got Firefox & Greasemonkey? Give yourself the option.

 

[treyhunsucker]

Thank You all Very Much, KevinADC's suggestions worked. I am very grateful, have a good day.

I am much more familiar with PHP, I will try to contribute to that forum section as much as possible.