The mount served fine on Linux and macOS but *BSD kernel NFS clients
refused it with "Authentication error". The MOUNT reply only ever
offered AUTH_NULL, and the OpenBSD/FreeBSD/NetBSD clients won't mount a
server unless AUTH_UNIX is among the offered flavors.
Add AUTH_UNIX to the advertised list. The server still doesn't inspect
the credential (there's no per-user access control here) so the AUTH_UNIX
cred the client then sends is read as an opaque blob and ignored, exactly
as the AUTH_NULL one was. No behaviour change for existing Linux/macOS
clients, and OpenBSD now mounts and reads files over the share.
Verified on a real OpenBSD 7.9 arm64 VM: registered rclone's server in
portmap and ran "mount_nfs -T localhost:/ /mnt"; the mount now succeeds
(MOUNT and GetAttr RPCs go through) and files read back correctly through
the mount, where before it stopped at the auth stage.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
