New MasterCard prefix is not supported

[ribasushi]

The current validation routine for credit cards has no provision for "2-series" master card numbers, like e.g. 2521 0000 0000 0006

Rollout begins in couple months: https://www.mastercard.us/en-us/issuers/get-support/2-series-bin-expansion.html

[gquipster]

Looking at: https://en.wikipedia.org/wiki/Payment_card_number#Issuer_identification_number_.28IIN.29

It looks like the constraint at line 657 needs changing roughly (this being done off top of my head in notepad) as follows:

return undef if (
	($card_type =~ /^v/i && substr($the_card, 0, 1) ne "4") # Visa
	|| (
		$card_type =~ /^m/i
		&& substr($the_card, 0, 4) !~ /^\d{4}$/
		&& (
			substr($the_card, 0, 4) < 2221
			&& substr($the_card, 0, 4) > 2720
		) # New 2017 range
		&& (
			substr($the_card, 0, 2) < 51
			&& substr($the_card, 0, 2) > 55
		) # Original range
	) # Mastercard
	|| (
		$card_type =~ /^d/i
		&& substr($the_card, 0, 4) ne "6011"
		&& substr($the_card, 0, 6) !~ /^\d{6}$/
		&& (
			substr($the_card, 0, 6) < 622126
			&& substr($the_card, 0, 6) > 622925
		)
		&& (
			substr($the_card, 0, 3) < 644
			&& substr($the_card, 0, 3) > 649
		)
		&& substr($the_card, 0, 2) ne "65"
	) # Discover Card
	|| (
		$card_type =~ /^a/i
		&& substr($the_card, 0, 2) ne "34"
		&& substr($the_card, 0, 2) ne "37"
	) # American Express
);

[ribasushi]

@dnmfarrell have you had a chance to look at this?

[dnmfarrell]

Uh no, sorry. I should update my GitHub notification settings. @ribasushi I'll look soon

[dnmfarrell]

I think 2cc14697d3c8d345b7748fbad3b272cd4d141acc addresses this. Looking at the code, I have some other concerns: I think it might be better if DFV used a module like Business::CreditCard to provide CC validation. Ideally, DFV wouldn't have any specific validation code beyond setting up the structures and routines to perform validation, but I think that horse has bolted...

[ribasushi]

@dnmfarrell if your medium-term goal is to move to Business::CreditCard - yes then 2cc1469 is a sufficient fix at this stage and should be released when you have time.

However if you do not have the time to follow through on that in the near future, I'd strongly recommend adopting @gquipster's solution higher up in this thread.