From 4edaa308888b4bd629fa025cc6d5b2bf1a2a51db Mon Sep 17 00:00:00 2001
From: Chuck Lever <chuck.lever@oracle.com>
Date: Sat, 16 Mar 2013 15:56:20 -0400
Subject: [PATCH] NFS: Use "krb5i" to establish NFSv4 state whenever possible
Currently our client uses AUTH_UNIX for state management on Kerberos
NFS mounts in some cases. For example, if the first mount of a
server specifies "sec=sys," the SETCLIENTID operation is performed
with AUTH_UNIX. Subsequent mounts using stronger security flavors
can not change the flavor used for lease establishment. This might
be less security than an administrator was expecting.
Dave Noveck's migration issues draft recommends the use of an
integrity-protecting security flavor for the SETCLIENTID operation.
Let's ignore the mount's sec= setting and use krb5i as the default
security flavor for SETCLIENTID.
If our client can't establish a GSS context (eg. because it doesn't
have a keytab or the server doesn't support Kerberos) we fall back
to using AUTH_NULL. For an operation that requires a
machine credential (which never represents a particular user)
AUTH_NULL is as secure as AUTH_UNIX.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
---
fs/nfs/nfs4client.c | 2 +-
fs/nfs/nfs4state.c | 37 +++++--------------------------------
2 files changed, 6 insertions(+), 33 deletions(-)
diff --git a/fs/nfs/nfs4client.c b/fs/nfs/nfs4client.c
index 17b34b2da2df6..bb9789ef1d498 100644
--- a/fs/nfs/nfs4client.c
+++ b/fs/nfs/nfs4client.c
@@ -199,7 +199,7 @@ struct nfs_client *nfs4_init_client(struct nfs_client *clp,
clp->rpc_ops = &nfs_v4_clientops;
__set_bit(NFS_CS_DISCRTRY, &clp->cl_flags);
- error = nfs_create_rpc_client(clp, timeparms, authflavour);
+ error = nfs_create_rpc_client(clp, timeparms, RPC_AUTH_GSS_KRB5I);
if (error < 0)
goto error;
diff --git a/fs/nfs/nfs4state.c b/fs/nfs/nfs4state.c
index b924bdd694948..a30f51eb048ff 100644
--- a/fs/nfs/nfs4state.c
+++ b/fs/nfs/nfs4state.c
@@ -1866,26 +1866,13 @@ int nfs4_discover_server_trunking(struct nfs_client *clp,
{
const struct nfs4_state_recovery_ops *ops =
clp->cl_mvops->reboot_recovery_ops;
- rpc_authflavor_t *flavors, flav, save;
struct rpc_clnt *clnt;
struct rpc_cred *cred;
- int i, len, status;
+ int i, status;
dprintk("NFS: %s: testing '%s'\n", __func__, clp->cl_hostname);
- len = NFS_MAX_SECFLAVORS;
- flavors = kcalloc(len, sizeof(*flavors), GFP_KERNEL);
- if (flavors == NULL) {
- status = -ENOMEM;
- goto out;
- }
- len = rpcauth_list_flavors(flavors, len);
- if (len < 0) {
- status = len;
- goto out_free;
- }
clnt = clp->cl_rpcclient;
- save = clnt->cl_auth->au_flavor;
i = 0;
mutex_lock(&nfs_clid_init_mutex);
@@ -1900,12 +1887,6 @@ again:
switch (status) {
case 0:
break;
-
- case -EACCES:
- if (clp->cl_machine_cred == NULL)
- break;
- /* Handle case where the user hasn't set up machine creds */
- nfs4_clear_machine_cred(clp);
case -NFS4ERR_DELAY:
case -ETIMEDOUT:
case -EAGAIN:
@@ -1914,17 +1895,12 @@ again:
dprintk("NFS: %s after status %d, retrying\n",
__func__, status);
goto again;
-
+ case -EACCES:
+ if (i++)
+ break;
case -NFS4ERR_CLID_INUSE:
case -NFS4ERR_WRONGSEC:
- status = -EPERM;
- if (i >= len)
- break;
-
- flav = flavors[i++];
- if (flav == save)
- flav = flavors[i++];
- clnt = rpc_clone_client_set_auth(clnt, flav);
+ clnt = rpc_clone_client_set_auth(clnt, RPC_AUTH_NULL);
if (IS_ERR(clnt)) {
status = PTR_ERR(clnt);
break;
@@ -1944,9 +1920,6 @@ again:
out_unlock:
mutex_unlock(&nfs_clid_init_mutex);
-out_free:
- kfree(flavors);
-out:
dprintk("NFS: %s: status = %d\n", __func__, status);
return status;
}
--
2.30.2