These subroutines tell you whether a credit card number is self-consistent -- whether the last digit of the number is a valid checksum for the preceding digits. The validate() subroutine returns 1 if the card number provided passes the checksum test, and 0 otherwise. The cardtype() subroutine returns a string containing the type of card: "MasterCard", "VISA", and so on. My list is not complete; I welcome additions. The generate_last_digit() subroutine computes and returns the last digit of the card given the preceding digits. With a 16-digit card, you provide the first 15 digits; the subroutine returns the sixteenth. This module does not tell you whether the number is on an actual card, only whether it might conceivably be on a real card. These subroutines will also work if you provide the arguments as numbers instead of strings, e.g. validate(5276440065421319).
Binary packages can be installed with the high-level tool pkgin (which can be installed with pkg_add) or pkg_add(1) (installed by default). The NetBSD packages collection is also designed to permit easy installation from source.
The pkg_admin audit command locates any installed package which has been mentioned in security advisories as having vulnerabilities.
Please note the vulnerabilities database might not be fully accurate, and not every bug is exploitable with every configuration.
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