parse_udphdr and parse_dnshdr methods undefined

[cookiengineer]

Where do these methods come from?

• parse_dnshdr
• parse_udphdr

When trying to google them, I find a lot of userspace code, but not a single definition of those methods. It doesn't come from libbpf or the linux kernel either (grepping their codebases reveals nothing).

Which version of which libraries did the experiments link against?