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

If an error condition occurs on rpc_pipefs creation, or the user mounts
rpc_pipefs and then unmounts it, then the dentries in struct gss_auth
need to be reset to NULL so that a second call to gss_pipes_dentries_destroy
doesn't try to free them again.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Don't pass the rpc_client as a parameter, when what we really want is
the net namespace.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

The clnt->cl_principal is being used exclusively to store the service
target name for RPCSEC_GSS/krb5 callbacks. Replace it with something that
is stored only in the RPCSEC_GSS-specific code.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Optimise away gss_encode_msg: we don't need to look up the pipe
version a second time.

Save the gss target name in struct gss_auth. It is a property of the
auth cache itself, and doesn't really belong in the rpc_client.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Store a pointer to the gss mechanism used in the rq_cred and cl_cred.
This will make it easier to enforce SP4_MACH_CRED, which needs to
compare the mechanism used on the exchange_id with that used on
protected operations.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Common helper to zero out fields of the svc_cred.
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Somebody noticed LTP was complaining about O_NONBLOCK opens of
/proc/net/rpc/use-gss-proxy succeeding and then a following read
hanging.

I'm not convinced LTP really has any business opening random proc files
and expecting them to behave a certain way.  Maybe this isn't really a
bug.

But in any case the O_NONBLOCK behavior could be useful for someone that
wants to test whether gss-proxy is up without waiting.
Reported-by: NJan Stancek <jstancek@redhat.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

This seems to have been overlooked when we did the namespace
conversion. If a container is running a legacy version of rpc.gssd
then it will be disrupted if the global 'pipe_version' is set by a
container running the new version of rpc.gssd.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Recent changes to the NFS security flavour negotiation mean that
we have a stronger dependency on rpc.gssd. If the latter is not
running, because the user failed to start it, then we time out
and mark the container as not having an instance. We then
use that information to time out faster the next time.

If, on the other hand, the rpc.gssd successfully binds to an rpc_pipe,
then we mark the container as having an rpc.gssd instance.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

If wait_event_interruptible_timeout() is successful, it returns
the number of seconds remaining until the timeout. In that
case, we should be retrying the upcall.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

This should return zero on success and -EBUSY on error so the type
needs to be int instead of bool.
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

The current code works, but sort of by accident: it obviously didn't
intend the error return to be interpreted as "true".
Reported-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

net/sunrpc/auth_gss/gss_rpc_xdr.c: In function ‘gssx_dec_option_array’:
net/sunrpc/auth_gss/gss_rpc_xdr.c:258: warning: ‘creds’ may be used uninitialized in this function

Return early if count is zero, to make it clearer to the compiler (and the
casual reviewer) that no more processing is done.
Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Just convert those messages to dprintk()s so that they can be used
when debugging.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Fix to return a negative error code from the error handling
case instead of 0, as returned elsewhere in this function.
Signed-off-by: NWei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Use preferable function name which implies using a pseudo-random
number generator.
Signed-off-by: NAkinobu Mita <akinobu.mita@gmail.com>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Acked-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Cc: Simo Sorce <simo@redhat.com>
Signed-off-by: NFengguang Wu <fengguang.wu@intel.com>

Though I wonder whether we should really just depend on CONFIG_PROC_FS
at some point.
Reported-by: Nkbuild test robot <fengguang.wu@intel.com>

The main advantge of this new upcall mechanism is that it can handle
big tickets as seen in Kerberos implementations where tickets carry
authorization data like the MS-PAC buffer with AD or the Posix Authorization
Data being discussed in IETF on the krbwg working group.

The Gssproxy program is used to perform the accept_sec_context call on the
kernel's behalf. The code is changed to also pass the input buffer straight
to upcall mechanism to avoid allocating and copying many pages as tokens can
be as big (potentially more in future) as 64KiB.
Signed-off-by: NSimo Sorce <simo@redhat.com>
[bfields: containerization, negotiation api]
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

This patch implements a sunrpc client to use the services of the gssproxy
userspace daemon.

In particular it allows to perform calls in user space using an RPC
call instead of custom hand-coded upcall/downcall messages.

Currently only accept_sec_context is implemented as that is all is needed for
the server case.

File server modules like NFS and CIFS can use full gssapi services this way,
once init_sec_context is also implemented.

For the NFS server case this code allow to lift the limit of max 2k krb5
tickets. This limit is prevents legitimate kerberos deployments from using krb5
authentication with the Linux NFS server as they have normally ticket that are
many kilobytes large.

It will also allow to lift the limitation on the size of the credential set
(uid,gid,gids) passed down from user space for users that have very many groups
associated. Currently the downcall mechanism used by rpc.svcgssd is limited
to around 2k secondary groups of the 65k allowed by kernel structures.
Signed-off-by: NSimo Sorce <simo@redhat.com>
[bfields: containerization, concurrent upcalls, misc. fixes and cleanup]
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

We expose this parameter for a future caller.
It will be used to extract the endtime from the gss-proxy upcall mechanism,
in order to set the rsc cache expiration time.
Signed-off-by: NSimo Sorce <simo@redhat.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Clean up: Reduce the symbol table footprint for auth_rpcgss.ko by
removing exported symbols for functions that are no longer used
outside of auth_rpcgss.ko.

The remaining two EXPORTs in gss_mech_switch.c get documenting
comments.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

gss_mech_get() is no longer used outside of gss_mech_switch.c.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Clean up.  This matches a similar API for the client side, and
keeps ULP fingers out the of the GSS mech switch.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Acked-by: NJ. Bruce Fields <bfields@redhat.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

The NFSv4 SECINFO operation returns a list of security flavors that
the server supports for a particular share.  An NFSv4 client is
supposed to pick a pseudoflavor it supports that corresponds to one
of the flavors returned by the server.

GSS flavors in this list have a GSS tuple that identify a specific
GSS pseudoflavor.

Currently our client ignores the GSS tuple's "qop" value.  A
matching pseudoflavor is chosen based only on the OID and service
value.

So far this omission has not had much effect on Linux.  The NFSv4
protocol currently supports only one qop value: GSS_C_QOP_DEFAULT,
also known as zero.

However, if an NFSv4 server happens to return something other than
zero in the qop field, our client won't notice.  This could cause
the client to behave in incorrect ways that could have security
implications.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

The current GSS mech switch can find and load GSS pseudoflavor
modules by name ("krb5") or pseudoflavor number ("390003"), but
cannot find GSS modules by GSS tuple:

  [ "1.2.840.113554.1.2.2", GSS_C_QOP_DEFAULT, RPC_GSS_SVC_NONE ]

This is important when dealing with a SECINFO request.  A SECINFO
reply contains a list of flavors the server supports for the
requested export, but GSS flavors also have a GSS tuple that maps
to a pseudoflavor (like 390003 for krb5).

If the GSS module that supports the OID in the tuple is not loaded,
our client is not able to load that module dynamically to support
that pseudoflavor.

Add a way for the GSS mech switch to load GSS pseudoflavor support
by OID before searching for the pseudoflavor that matches the OID
and service.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

A SECINFO reply may contain flavors whose kernel module is not
yet loaded by the client's kernel.  A new RPC client API, called
rpcauth_get_pseudoflavor(), is introduced to do proper checking
for support of a security flavor.

When this API is invoked, the RPC client now tries to load the
module for each flavor first before performing the "is this
supported?" check.  This means if a module is available on the
client, but has not been loaded yet, it will be loaded and
registered automatically when the SECINFO reply is processed.

The new API can take a full GSS tuple (OID, QoP, and service).
Previously only the OID and service were considered.

nfs_find_best_sec() is updated to verify all flavors requested in a
SECINFO reply, including AUTH_NULL and AUTH_UNIX.  Previously these
two flavors were simply assumed to be supported without consulting
the RPC client.

Note that the replaced version of nfs_find_best_sec() can return
RPC_AUTH_MAXFLAVOR if the server returns a recognized OID but an
unsupported "service" value.  nfs_find_best_sec() now returns
RPC_AUTH_UNIX in this case.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

The NFSv4 SECINFO procedure returns a list of security flavors.  Any
GSS flavor also has a GSS tuple containing an OID, a quality-of-
protection value, and a service value, which specifies a particular
GSS pseudoflavor.

For simplicity and efficiency, I'd like to return each GSS tuple
from the NFSv4 SECINFO XDR decoder and pass it straight into the RPC
client.

Define a data structure that is visible to both the NFS client and
the RPC client.  Take structure and field names from the relevant
standards to avoid confusion.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Commit f344f6df "SUNRPC: Auto-load RPC authentication kernel
modules", Mon Mar 20 13:44:08 2006, adds a request_module() call
in rpcauth_create() to auto-load RPC security modules when a ULP
tries to create a credential of that flavor.

In rpcauth_create(), the name of the module to load is built like
this:

	request_module("rpc-auth-%u", flavor);

This means that for, say, RPC_AUTH_GSS, request_module() is looking
for a module or alias called "rpc-auth-6".

The GSS module is named "auth_rpcgss", and commit f344f6df does not
add any new module aliases.  There is also no such alias provided in
/etc/modprobe.d on my system (Fedora 16).  Without this alias, the
GSS module is not loaded on demand.

This is used by rpcauth_create().  The pseudoflavor_to_flavor() call
can return RPC_AUTH_GSS, which is passed to request_module().
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

krb5 mounts started failing as of
683428fa "sunrpc: Update svcgss xdr
handle to rpsec_contect cache".

The problem is that mounts are usually done with some host principal
which isn't normally mapped to any user, in which case svcgssd passes
down uid -1, which the kernel is then expected to map to the
export-specific anonymous uid or gid.

The new uid_valid/gid_valid checks were therefore causing that downcall
to fail.

(Note the regression may not have been seen with older userspace that
tended to map unknown principals to an anonymous id on their own rather
than leaving it to the kernel.)
Reviewed-by: N"Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Since commit 620038f6, gcc is throwing the following warning:

  CC [M]  net/sunrpc/auth_gss/auth_gss.o
In file included from include/linux/sunrpc/types.h:14:0,
                 from include/linux/sunrpc/sched.h:14,
                 from include/linux/sunrpc/clnt.h:18,
                 from net/sunrpc/auth_gss/auth_gss.c:45:
net/sunrpc/auth_gss/auth_gss.c: In function ‘gss_pipe_downcall’:
include/linux/sunrpc/debug.h:45:10: warning: ‘timeout’ may be used
uninitialized in this function [-Wmaybe-uninitialized]
    printk(KERN_DEFAULT args); \
          ^
net/sunrpc/auth_gss/auth_gss.c:194:15: note: ‘timeout’ was declared here
  unsigned int timeout;
               ^
If simple_get_bytes returns an error, then we'll end up calling printk
with an uninitialized timeout value. Reasonably harmless, but fairly
simple to fix by removing the printout of the uninitialised parameters.

Cc: Andy Adamson <andros@netapp.com>
Signed-off-by: NJeff Layton <jlayton@redhat.com>
[Trond: just remove the parameters rather than initialising timeout]
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

For most of SUNRPC caches (except NFS DNS cache) cache_detail->cache_upcall is
redundant since all that it's implementations are doing is calling
sunrpc_cache_pipe_upcall() with proper function address argument.
Cache request function address is now stored on cache_detail structure and
thus all the code can be simplified.
Now, for those cache details, which doesn't have cache_upcall callback (the
only one, which still has is nfs_dns_resolve_template)
sunrpc_cache_pipe_upcall will be called instead.
Signed-off-by: NStanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

This callback will allow to simplify upcalls in further patches in this
series.
Signed-off-by: NStanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

For each received uid call make_kuid and validate the result.
For each received gid call make_kgid and validate the result.

Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

- Use from_kuid when generating the on the wire uid values.
- Use make_kuid when reading on the wire values.

In gss_encode_v0_msg, since the uid in gss_upcall_msg is now a kuid_t
generate the necessary uid_t value on the stack copy it into
gss_msg->databuf where it can safely live until the message is no
longer needed.

Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>

When printing kuids and kgids for debugging purpropses convert them
to ordinary integers so their values can be fed to the oridnary
print functions.

Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>