Autobinding is handled by the rpciod process, not in user processes
that are generating regular RPC requests.  Thus autobinding is usually
not affected by signals targetting user processes, such as KILL or
timer expiration events.

In addition, an RPC request generated by a user process that has
RPC_TASK_SOFTCONN set and needs to perform an autobind will hang if
the remote rpcbind service is not available.

For rpcbind queries on connection-oriented transports, let's use the
new soft connect semantic to return control to the user's process
quickly, if the kernel's rpcbind client can't connect to the remote
rpcbind service.

Logic is introduced in call_bind_status() to handle connection errors
that occurred during an asynchronous rpcbind query.  The logic
abandons the rpcbind query if the RPC request has SOFTCONN set, and
retries after a few seconds in the normal case.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Use TCP with the soft connect semantic for local rpcbind upcalls so
the kernel can detect immediately if the local rpcbind daemon is not
running.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>

The kernel's rpcbind client creates and deletes an rpc_clnt and its
underlying transport socket for every upcall to the local rpcbind
daemon.

When starting a typical NFS server on IPv4 and IPv6, the NFS service
itself does three upcalls (one per version) times two upcalls (one
per transport) times two upcalls (one per address family), making 12,
plus another one for the initial call to unregister previous NFS
services.  Starting the NLM service adds an additional 13 upcalls,
for similar reasons.

(Currently the NFS service doesn't start IPv6 listeners, but it will
soon enough).

Instead, let's create an rpc_clnt for rpcbind upcalls during the
first local rpcbind query, and cache it.  This saves the overhead of
creating and destroying an rpc_clnt and a socket for every upcall.

The new logic also prevents the kernel from attempting an RPCB_SET or
RPCB_UNSET if it knows from the start that the local portmapper does
not support rpcbind protocol version 4.  This will cut down on the
number of rpcbind upcalls in legacy environments.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>

Clean up: At one point, rpcb_local_clnt() handled IPv6 loopback
addresses too, but it doesn't any more; only IPv4 loopback is used
now.  Get rid of the @addr and @addrlen arguments to
rpcb_local_clnt().
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Clean up: Replace PROC macro with open coded C99 structure
initializers to improve readability.

The rpcbind v4 GETVERSADDR procedure is never sent by the current
implementation, so it is not copied to the new structures.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Replace the open-coded decode logic for PMAP_GETPORT/RPCB_GETADDR with
an xdr_stream-based implementation, similar to what NFSv4 uses, to
protect against buffer overflows.  The new implementation also checks
that the incoming port number is reasonable.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Replace the open-coded decode logic for rpcbind UNSET results with an
xdr_stream-based implementation, similar to what NFSv4 uses, to
protect against buffer overflows.

The new function is unused for the moment.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Replace the open-coded encode logic for rpcbind arguments with an
xdr_stream-based implementation, similar to what NFSv4 uses, to
better protect against buffer overflows.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

RPC universal address generation is currently done in several places:
rpcb_clnt.c, nfs4proc.c xprtsock.c, and xprtrdma.c.  Remove the
redundant cases that convert a socket address to a universal
address.  The nfs4proc.c case takes a pre-formatted presentation
address string, not a socket address, so we'll leave that one.

Because the new uaddr constructor uses the recently introduced
rpc_ntop(), it now supports proper "::" shorthanding for IPv6
addresses.  This allows the kernel to register properly formed
universal addresses with the local rpcbind service, in _all_ cases.

The kernel can now also send properly formed universal addresses in
RPCB_GETADDR requests, and support link-local properly when
encoding and decoding IPv6 addresses.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Clean up: To make subsequent patches cleaner, move the XDR data type
size macros to the top of the file (similar to nfs4xdr.c) first.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Move error reporting for RPC registration to rpcb_register's caller.

This way the caller can choose to recover silently from certain
errors, but report errors it does not recognize.  Error reporting
for kernel RPC service registration is now handled in one place.

This patch is part of a series that addresses
   http://bugzilla.kernel.org/show_bug.cgi?id=12256Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

The user space TI-RPC library uses an empty string for the universal
address when unregistering all target addresses for [program, version].
The kernel's rpcb client should behave the same way.

Here, we are switching between several registration methods based on
the protocol family of the incoming address.  Rename the other rpcbind
v4 registration functions to make it clear that they, as well, are
switched on protocol family.  In /etc/netconfig, this is either "inet"
or "inet6".

NB: The loopback protocol families are not supported in the kernel.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

RFC 1833 has little to say about the contents of r_owner; it only
specifies that it is a string, and states that it is used to control
who can UNSET an entry.

Our port of rpcbind (from Sun) assumes this string contains a numeric
UID value, not alphabetical or symbolic characters, but checks this
value only for AF_LOCAL RPCB_SET or RPCB_UNSET requests.  In all other
cases, rpcbind ignores the contents of the r_owner string.

The reference user space implementation of rpcb_set(3) uses a numeric
UID for all SET/UNSET requests (even via the network) and an empty
string for all other requests.  We emulate that behavior here to
maintain bug-for-bug compatibility.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Clean up: Simplify rpcb_v4_register() and its helpers by moving the
details of sockaddr type casting to rpcb_v4_register()'s helper
functions.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

The kernel uses an IPv6 loopback address when registering its AF_INET6
RPC services so that it can tell whether the local portmapper is
actually IPv6-enabled.

Since the legacy portmapper doesn't listen on IPv6, however, this
causes a long timeout on older systems if the kernel happens to try
creating and registering an AF_INET6 RPC service.  Originally I wanted
to use a connected transport (either TCP or connected UDP) so that the
upcall would fail immediately if the portmapper wasn't listening on
IPv6, but we never agreed on what transport to use.

In the end, it's of little consequence to the kernel whether the local
portmapper is listening on IPv6.  It's only important whether the
portmapper supports rpcbind v4.  And the kernel can't tell that at all
if it is sending requests via IPv6 -- the portmapper will just ignore
them.

So, send both rpcbind v2 and v4 SET/UNSET requests via IPv4 loopback
to maintain better backwards compatibility between new kernels and
legacy user space, and prevent multi-second hangs in some cases when
the kernel attempts to register RPC services.

This patch is part of a series that addresses

   http://bugzilla.kernel.org/show_bug.cgi?id=12256Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

In 2007, commit e65fe397 added
additional sanity checking to rpcb_decode_getaddr() to make sure we
were getting a reply that was long enough to be an actual universal
address.  If the uaddr string isn't long enough, the XDR decoder
returns EIO.

However, an empty string is a valid RPCB_GETADDR response if the
requested service isn't registered.  Moreover, "::.n.m" is also a
valid RPCB_GETADDR response for IPv6 addresses that is shorter
than rpcb_decode_getaddr()'s lower limit of 11.  So this sanity
check introduced a regression for rpcbind requests against IPv6
remotes.

So revert the lower bound check added by commit
e65fe397, and add an explicit check
for an empty uaddr string, similar to libtirpc's rpcb_getaddr(3).
Pointed-out-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Using NIPQUAD() with NIPQUAD_FMT, %d.%d.%d.%d or %u.%u.%u.%u
can be replaced with %pI4
Signed-off-by: NHarvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NHarvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NHarvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Despite the fact that cloned rpc clients won't have the cl_autobind flag
set, they may still find themselves calling rpcb_getport_async(). For this
to happen, it suffices for a _parent_ rpc_clnt to use autobinding, in which
case any clone may find itself triggering the !xprt_bound() case in
call_bind().

The correct fix for this is to walk back up the tree of cloned rpc clients,
in order to find the parent that 'owns' the transport, either because it
has clnt->cl_autobind set, or because it originally created the
transport...
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

The RPCB XDR functions are used for multiple procedures.  For instance,
rpcb_encode_getaddr() is used for RPCB_GETADDR, RPCB_SET, and
RPCB_UNSET.  Make the XDR debug messages more generic so they are less
confusing.

And, unlike in other RPC consumers in the kernel, a single debug flag
enables all levels of debug messages in the RPC bind client, including
XDR debug messages.  Since the XDR decoders already report success or
failure in this case, remove redundant debug messages in the mid-level
rpcb_register_call() function.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

Clean up: When doing an RPCB_SET, make the kernel's rpcb client use the
shorthand "::" for the universal form of the IPv6 ANY address.

Without this patch, rpcbind will advertise:

  0000:0000:0000:0000:0000:0000:0000:0000.x.y

This is cosmetic only.  It cleans up the display of information from
/sbin/rpcinfo.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

Bruce suggested there's no need to expose the difference between an error
sending the PMAP_SET request and an error reply from the portmapper to
rpcb_register's callers.  The user space equivalent of rpcb_register() is
pmap_set(3), which returns a bool_t : either the PMAP set worked, or it
didn't.  Simple.

So let's remove the "*okay" argument from rpcb_register() and
rpcb_v4_register(), and simply return an error if any part of the call
didn't work.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

Introduce a new API to register RPC services on IPv6 interfaces to allow
the NFS server and lockd to advertise on IPv6 networks.

Unlike rpcb_register(), the new rpcb_v4_register() function uses rpcbind
protocol version 4 to contact the local rpcbind daemon.  The version 4
SET/UNSET procedures allow services to register address families besides
AF_INET, register at specific network interfaces, and register transport
protocols besides UDP and TCP.  All of this functionality is exposed via
the new rpcb_v4_register() kernel API.

A user-space rpcbind daemon implementation that supports version 4 of the
rpcbind protocol is required in order to make use of this new API.

Note that rpcbind version 3 is sufficient to support the new rpcbind
facilities listed above, but most extant implementations use version 4.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

rpcbind version 4 registration will reuse part of rpcb_register, so just
split it out into a separate function now.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Clean up: Callers that required a privileged source port now use
rpcb_create_local(), so we can remove the @privileged argument from
rpcb_create().
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Add rpcb_create_local() for use by rpcb_register() and upcoming IPv6
registration functions.

Ensure any errors encountered by rpcb_create_local() are properly
reported.

We can also use a statically allocated constant loopback socket address
instead of one allocated on the stack and initialized every time the
function is called.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

The rpcbind versions 3 and 4 SET and UNSET procedures use the same
arguments as the GETADDR procedure.

While definitely a bug, this hasn't been a problem so far since the
kernel hasn't used version 3 or 4 SET and UNSET.  But this will change
in just a moment.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

If another task is busy in rpcb_getport_async number, it is more efficient
to have it wake us up when it has finished instead of arbitrarily sleeping
for 5 seconds.

Also ensure that rpcb_wake_rpcbind_waiters() is called regardless of
whether or not rpcb_getport_done() gets called.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Some server vendors support the higher versions of rpcbind only for
AF_INET6.  The kernel doesn't need to use v3 or v4 for AF_INET anyway,
so change the kernel's rpcbind client to query AF_INET servers over
rpcbind v2 only.

This has a few interesting benefits:

1. If the rpcbind request is going over TCP, and the server doesn't
   support rpcbind versions 3 or 4, the client reduces by two the number
   of ephemeral ports left in TIME_WAIT for each rpcbind request.  This
   will help during NFS mount storms.

2. The rpcbind interaction with servers that don't support rpcbind
   versions 3 or 4 will use less network traffic.  Also helpful
   during mount storms.

3. We can eliminate the kernel build option that controls whether the
   kernel's rpcbind client uses rpcbind version 3 and 4 for AF_INET
   servers.  Less complicated kernel configuration...
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Some rpcbind servers that do support rpcbind version 4 do not support
the GETVERSADDR procedure.  Use GETADDR for querying rpcbind servers
via rpcbind version 4 instead of GETVERSADDR.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Clean up: Change the version 2 procedure name to GETPORT.  It's the same
procedure number as GETADDR, but version 2 implementations usually refer
to it as GETPORT.

This also now matches the procedure name used in the version 2 procedure
entry in the rpcb_next_version[] array, making it slightly less confusing.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Clean up: Replace naked integers that represent rpcbind protocol versions.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Clean up dprintk's in rpcb client's XDR decoder functions.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Now that rpcb_next_version has been split into an IPv4 version and an IPv6
version, we Oops when rpcb_call_async attempts to look up the IPv6-specific
RPC procedure in rpcb_next_version.

Fix the Oops simply by having rpcb_getport_async pass the correct RPC
procedure as an argument.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

It is wrong to be freeing up the rpcbind arguments if the call to
rpcb_call_async() fails, since they should already have been freed up by
rpcb_map_release().
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

__FUNCTION__ is gcc-specific, use __func__
Signed-off-by: NHarvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>