Greetings, monks. :)

Assume I have some Perl code doing crypto stuff, which needs to hold a key in memory. When the code is finished doing it's thing, the key should be erased. In C, this is easy... I could just say

memset(sensitive_buf, 0, sizeof sensitive_buf);

Done - as well as I can in software, anyway.

But what about Perl? If I wrote something like this:

$sensitive_1 = 0;

$_ = 0 for @sensitive_2;

[download]

is that good enough? Or would it leak information, or generally not be as secure as I want?

Is this even a problem? Should I go about doing crypto from Perl some other way, like calling into a C library that erases keys itself? Am I missing anything?

- Eagerly awaiting your collective wisdom.

email: perl -e 'print reverse map { chr( ord($_)-1 ) } split //, "\x0bufo/hojsfufqAofc";'

In reply to Is it possible to sanitize Perl memory that holds sensitive data? (crypto implications) by missingthepoint

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