Comment by 1vuio0pswjnm7

20 days ago

"One such implementation that broke is the getaddrinfo function in glibc, which is commonly used on Linux for DNS resolution. When looking at its getanswer_r implementation, we can indeed see it expects to find the CNAME records before any answers:"

Wherever possible I compile with gethostbyname instead of getaddrinfo. I use musl instead of glibc

Nothing against IPv6 but I do not use it on the computers and networks I control

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1vuio0pswjnm7

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1vuio0pswjnm7  19 days ago

Sometimes software written by others provides compile-time options to disable getaddrinfo or IPv6. Sometimes the software onllly uses gethostbyname

For example,

tinydns (only uses gethostbyname)

nsd (--disable-ipv6)

I compile static binaries with musl. I do not use glibc

1vuio0pswjnm7  19 days ago

NB. This is not code that belongs to me

When compiling software written by others, sometimes there are compile-time options that allow not using getaddrinfo or IPv6

For example,

links (--without-getaddrinfo)

haproxy (USE_GETADDRINFO="")

tnftp (--disable-ipv6)

elinks (--disable-ipv6)

wolfssl (ipv6 disabled by default)

stunnel (--disable-ipv6)

socat (--disable-ipv6)

and many more

Together with localhost TLS forward proxy I also use lots of older software that only used gethostbyname, e.g., original netcat, ucspi-tcp, libwww, original links, etc.

Generally I avoid mobile OS (corporate OS for data collection, surveillance and ad services)

Mobile data is disabled. I almost never use cellular networks for internet

Mobile sucks for internet IMHO; I have zero expectation re: speed and I cannot control what ISPs choose to do

For me, non-corporate UNIX-like OS are smaller, faster, easier to control, more interesting

immibis  20 days ago

Your code runs slower on mobile devices, since (as a rule of thumb) mobile networks are ipv6-only and ipv4 traffic has to pass through a few layers of tunneling.