From 9568c5e9a61de49f67f524404a27a1014a8d7f1e Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Sat, 16 Mar 2013 15:54:43 -0400 Subject: SUNRPC: Introduce rpcauth_get_pseudoflavor() 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: Chuck Lever Signed-off-by: Trond Myklebust --- fs/nfs/nfs4namespace.c | 41 +++++++++++++++++++++++------------------ 1 file changed, 23 insertions(+), 18 deletions(-) (limited to 'fs/nfs') diff --git a/fs/nfs/nfs4namespace.c b/fs/nfs/nfs4namespace.c index 88231c92317c..cdb0b41a4810 100644 --- a/fs/nfs/nfs4namespace.c +++ b/fs/nfs/nfs4namespace.c @@ -134,33 +134,38 @@ static size_t nfs_parse_server_name(char *string, size_t len, return ret; } +/** + * nfs_find_best_sec - Find a security mechanism supported locally + * @flavors: List of security tuples returned by SECINFO procedure + * + * Return the pseudoflavor of the first security mechanism in + * "flavors" that is locally supported. Return RPC_AUTH_UNIX if + * no matching flavor is found in the array. The "flavors" array + * is searched in the order returned from the server, per RFC 3530 + * recommendation. + */ rpc_authflavor_t nfs_find_best_sec(struct nfs4_secinfo_flavors *flavors) { - struct gss_api_mech *mech; - struct xdr_netobj oid; + rpc_authflavor_t pseudoflavor; + struct nfs4_secinfo4 *secinfo; unsigned int i; - rpc_authflavor_t pseudoflavor = RPC_AUTH_UNIX; for (i = 0; i < flavors->num_flavors; i++) { - struct nfs4_secinfo4 *flavor = &flavors->flavors[i]; - - if (flavor->flavor == RPC_AUTH_NULL || flavor->flavor == RPC_AUTH_UNIX) { - pseudoflavor = flavor->flavor; - break; - } else if (flavor->flavor == RPC_AUTH_GSS) { - oid.len = flavor->flavor_info.oid.len; - oid.data = flavor->flavor_info.oid.data; - mech = gss_mech_get_by_OID(&oid); - if (!mech) - continue; - pseudoflavor = gss_svc_to_pseudoflavor(mech, - flavor->flavor_info.service); - gss_mech_put(mech); + secinfo = &flavors->flavors[i]; + + switch (secinfo->flavor) { + case RPC_AUTH_NULL: + case RPC_AUTH_UNIX: + case RPC_AUTH_GSS: + pseudoflavor = rpcauth_get_pseudoflavor(secinfo->flavor, + &secinfo->flavor_info); + if (pseudoflavor != RPC_AUTH_MAXFLAVOR) + return pseudoflavor; break; } } - return pseudoflavor; + return RPC_AUTH_UNIX; } static rpc_authflavor_t nfs4_negotiate_security(struct inode *inode, struct qstr *name) -- cgit v1.2.3