x/crypto: increasing the default BCrypt cost

[n-bruno]

Looking at git blame, it appears the DefaultCost for the Bcrypt library has remained unchanged for the past 14 years.

To keep up with modern hardware, I propose upgrading the Bcrypt library's DefaultCost from 10 to 12 to match the PHP 8.4 recent update in 2024.

Please see PHP's RFC for research on this topic, but please keep in mind the benchmarks are specific to PHP: https://wiki.php.net/rfc/bcrypt_cost_2023

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Message from Gopher Robot:

Patch Set 1:

(1 comment)

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Patch Set 1:

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Message from Sean Liao:

Patch Set 2: Hold+1

(1 comment)

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Message from N:

Patch Set 2:

(2 comments)

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