sort -u not behaving the same between coreutils and uutils (a rewrite of coreutils in Rust)

[pyke369]

Description

Two different versions of the sort tool apparently do not behave the same, and this is problematic on how dehydrated handle certificates with wildcard ("star") domain aliases. For instance when you have such following line in the domains.txt file:

domain.com *.domain.com > domain.com

the normalize_san_list() function (and the inlined code before it existed) thinks the certificate needs to be renewed b/c the SAN list appear to have changed:

Processing domain.com with alternative names: *.domain.com
 + Checking domain name(s) of existing cert... changed!
 + Domain name(s) are not matching!
 + Names in old certificate: *.domain.com
 + Configured names: domain.com
 + Forcing renew.

Problem

With coreutils sort:

$ (echo 'domain.com'; echo '*.domain.com'; echo 'domain.com') | sort -u
*.domain.com
domain.com

With uutils sort:

$ (echo 'domain.com'; echo '*.domain.com'; echo 'domain.com') | sort -u
domain.com    <--- the additional wildcard domain is silently discarded

Solution

Add -i (and optionnally -s) option(s) to the existsing -u option.

With coreutils sort:

$ (echo 'domain.com'; echo '*.domain.com'; echo 'domain.com') | sort -uis
*.domain.com
domain.com

With uutils sort:

$ (echo 'domain.com'; echo '*.domain.com'; echo 'domain.com') | sort -uis
*.domain.com
domain.com

[lukas2511]

This looks really weird, why is uutils discarding the wildcard domain during sorting? Maybe open a bug with them? I'll probably add the workaround either way, but this is a weird inconsistency.

[pyke369]

I totally agree with you on the weirdness. Seems like the * has some significance in the Rust version (for some reason) leading to this inconsistency. I noticed the problem after upgrading to a recent version of Ubuntu and getting uutils-based commands in the way...