every upcall (except few) pass session and open_state pointer, so
add that to marshal_nfs41_header() in the driver. remove passing
of session and open_state elsewhere in marshal functions.
in the deamon, upcall.c now reads and stores pointers to session
and open_state in nfs41_upcall datastructure instead of having
each individual upcall store their own pointers. setattrl
and readdir args keeping pointer because the rest of the code
uses them a lot.
in upcall_parse() up refcounts on session and open_state if
valid handles were passed in. down refcounts upcall_cleanup() as
before. but need to be careful with count value for mount and open
upcalls. we need to take an extra ref because upcall_cleanup() now
will always decrement it.
this commit does NOT have correct windows to nfs4 acl mappings but
rather has the wrapper functions defined for mapping them.
cthon tests still work with these mappings.
Basic handling of owner and group security query (no dacl).
Added new upcall for NFS41_ACL_QUERY (driver and daemon code).
Daemon, upon getting NFS41_ACL_QUERY first places a getattr that has
owner, group attribute request. We currently don't cache them!!!
Then, we parse nfs4name format (ie user@domain or group@domain)
into user and domain. We currently ignore domain part!!!
Then, we assume that whatever we are mapping is "known" locally
(ie LookupAccountName() api which retrieves a SID for a given name).
Mapping from name to SID can only be done in the userland. We then
copy the bytes via the upcall pipe to the kernel. If the received
user or group cant be mapped via LookupAccoundName(), we create a
well known null SID as the reply.
Kernel creates a security descriptor in the absolute-format and adds
owner and group sids to it. Important: RtlSetOwner/Group functions only
work with absolute-format security descriptor, however the reply to the
user needs to be in the self-relative format.
The way security query works is that it passes us a buffer to be filled
with the security context. However the user doesn't know how big the
buffer should be so, the user is allowed to pass a null buffer and have
the kernel return how much memory is needed. This leads to 2 security
queries => 2 NFS41_ACL_QUERY upcalls => 2 getattr rpcs... It should be
improved.
TODO:
- need to add caching of owner/group attributes for a file?
- need to add calls to LDAP for more general mapping?
- need to cache reply of the ACL if supplied length is 0?
upcall_cleanup() is called after every upcall regardless of errors. if we get a CLOSE upcall after a daemon restart, we still call cleanup_close() and crash attempting to access the invalid open state pointer. avoid calling upcall-specific cancel routines for these version mismatch errors
Signed-off-by: Casey Bodley <cbodley@citi.umich.edu>
to determine that the daemon has restarted -- rather that daemon is receiving upcalls from the kernel that were processed by the old instance of the daemon -- add a version to the upcall mechanism.
when daemon starts up it generates a version number (just a timestamp). it passes this value to the driver on start up via "start_ioctl" downcall. the driver saves that value in its device extensions. it uses that value in the mount and shtudown upcalls.
when daemon replies to the mount command it again sends its version as a part of the reply. this reply is stored in driver;s netroot extensions. the driver uses netroot's value in each upcall to the daemon.
if the daemon receives an upcall for an operation where the included version does not equal to the its current version, it fails the upcall (error_code=116).
a restart of the daemon would change driver's device extension value which the driver will then use in the new mount upcalls that would establish new sessions. then the correct daemon version would be returned as a part of the mount downcalled and saved in the netroot.
very similar to the issue with nfs41_open_state, an abandoned upcall could outlive its mount. to prevent their nfs41_root from being freed, upcalls need to hold a reference until they're finished. this also keeps all of its clients/sessions/rpc connections alive
Signed-off-by: Casey Bodley <cbodley@citi.umich.edu>
added call to upcall_cleanup() after both upcall_marshall() and upcall_cancel()
individual upcall operations define their nfs41_upcall_op structs locally, instead of putting tons of function prototypes in upcall.c
made the upcall_marshall() function optional; most marshall functions are noops
Signed-off-by: Casey Bodley <cbodley@citi.umich.edu>
