Find Credit Card Numbers and Mask only 6 digits in a logfile

gtk has asked for the wisdom of the Perl Monks concerning the following question:

I wanted to find the card numbers in a logfiles and mask the card numbers. Can you please let me know what is the easiest way to do this?

Card Number format => 1234567890123456 and I want to mask the number like his one 123456******3456

The problem is to identify the number in the file because I cannot open the file because sometimes files are too large. The next problem is mask the card number from 7th digit to 12th digit.

The logfile how the crd number stored

Dec 10 14:00:00 AAA: ABC * 11111 *                                    
+  CRD : 1234567890123456
[download]

Comment on Find Credit Card Numbers and Mask only 6 digits in a logfile Download Code

Replies are listed 'Best First'.
Re: Find Credit Card Numbers and Mask only 6 digits in a logfile by Marshall (Canon) on Apr 30, 2018 at 11:07 UTC
I don't understand this: "The problem is to identify the number in the file because I cannot open the file because sometimes files are too large.". Maybe you are trying to read the whole file into memory at once? Open the file and read it line by line. Use a regex to modify the number, perhaps something as simple as this: `use strict; use warnings; my $n = 'asdfklj fuyy23 1234567890123456 78vc'; $n =~ s/(\d{6,6})(\d{6,6})(\d{4,4})/$1****$3/; print "$1 $2 $3\n"; print $n; __END__ 123456 789012 3456 asdfklj fuyy23 123456****3456 78vc` [download]	[reply] [d/l]
Re: Find Credit Card Numbers and Mask only 6 digits in a logfile by marto (Cardinal) on Apr 30, 2018 at 10:55 UTC
Why are you storing credit card details in plain text in a log file?	[reply]
Re^2: Find Credit Card Numbers and Mask only 6 digits in a logfile by VinsWorldcom (Prior) on Apr 30, 2018 at 12:05 UTC
Why are you storing credit card details in plain text in a log file? Not storing them; parsing the dump of a breach for posting on the dark web ... whoops, did I say that out loud?	[reply]
Re^2: Find Credit Card Numbers and Mask only 6 digits in a logfile by gtk (Acolyte) on Apr 30, 2018 at 10:59 UTC
It is good question, due to some debugging purpose we have disabled the encryption and currently we want to mask only 6 digits.	[reply]
Re^3: Find Credit Card Numbers and Mask only 6 digits in a logfile by marto (Cardinal) on Apr 30, 2018 at 11:07 UTC
This is terrible practice, and depending where you are a PCI compliance failure.	[reply]
Re^4: Find Credit Card Numbers and Mask only 6 digits in a logfile by gtk (Acolyte) on Apr 30, 2018 at 13:16 UTC
Re: Find Credit Card Numbers and Mask only 6 digits in a logfile by shmem (Chancellor) on Apr 30, 2018 at 10:59 UTC
The problem is to identify the number in the file because I cannot open the file because sometimes files are too large. The problem is not opening the file. If opening fails, it is because you are not allowed to do that (permissions), file doesn't exist or isn't a file. Most likely, what fails is reading the whole file into memory. Show some code! so we can see where it probably fails. Matching `123456******3456` in perl is `m/123456\d{6}3456/`. See perlre. perl -le'print map{pack c,($-++?1:13)+ord}split//,ESEL'	[reply] [d/l] [select]
Re: Find Credit Card Numbers and Mask only 6 digits in a logfile by kcott (Archbishop) on May 01, 2018 at 09:58 UTC
G'day gtk, I don't see how the size of the file prevents you from opening it. Perhaps you meant something else. If you show us the code you're using, we can probably point you in the right direction. As far as "masking" goes, substr would seem to be an appropriate tool: `$ perl -E 'my $x = "1234567890123456"; say $x; substr $x, 6, 6, ""x6; + say $x' 1234567890123456 123456*****3456` [download] — Ken	[reply] [d/l]