core: no longer supply bogus services to callbacks #523
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It was technically a DOS allowing packets with service names like "bogus.service.local" to bring down `avahi-browse -a`. In practice it was usually triggered by misconfigured smart devices but it isn't that hard to forge packets like that and send them deliberately. The tests are added to make sure invalid service names are rejected and valid service names keep working. The fuzz target is updated to make sure that avahi_service_name_split always supplies valid arguments to avahi_service_name_join. avahi now logs what exactly it fails to split ``` avahi-daemon[176]: Failed to split service name '0.1.9.1.8.8.e.f.f.f.f.a.a.1.4.7.0.0.0.0.0.0.0.0.0.0.0.0.0.8.e.f.ip6.arpa' avahi-daemon[176]: Failed to split service name 'bogus\032.\032\209\129\208\181\209\128\208\178\208\184\209\129.local' avahi-daemon[176]: Failed to split service name '255.20.254.169.in-addr.arpa' avahi-daemon[176]: Failed to split service name 'bogus\032.\032\209\129\208\181\209\128\208\178\208\184\209\129.local' avahi-daemon[176]: Failed to split service name '33.93.168.192.in-addr.arpa' ``` when --debug is passed to it (which makes that part consistent with the other places where weird packets are rejected). Closes avahi#212
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It was technically a DOS allowing packets with service names like "bogus.service.local" to bring down
avahi-browse -a. In practice it was usually triggered by misconfigured smart devices but it isn't that hard to forge packets like that and send them deliberately.The tests are added to make sure invalid service names are rejected and valid service names keep working. The fuzz target is updated to make sure that avahi_service_name_split always supplies valid arguments to avahi_service_name_join. avahi now logs what exactly it fails to split
when --debug is passed to it (which makes that part consistent with the other places where weird packets are rejected).
Closes #212