nfsd4: use callback security parameters in create_session

We're currently ignoring the callback security parameters specified in
create_session, and just assuming the client wants auth_sys, because
that's all the current linux client happens to care about.  But this
could cause us callbacks to fail to a client that wanted something
different.

For now, all we're doing is no longer ignoring the uid and gid passed in
the auth_sys case.  Further patches will add support for auth_null and
gss (and possibly use more of the auth_sys information; the spec wants
us to use exactly the credential we're passed, though it's hard to
imagine why a client would care).

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

diff --git a/fs/nfsd/nfs4callback.c b/fs/nfsd/nfs4callback.c
index bdf29c9..b32639e 100644 (file)
--- a/fs/nfsd/nfs4callback.c
+++ b/fs/nfsd/nfs4callback.c
@@ -630,6 +630,31 @@ static int max_cb_time(void)
        return max(nfsd4_lease/10, (time_t)1) * HZ;
 }
 
+static struct rpc_cred *callback_cred;
+
+int set_callback_cred(void)
+{
+       if (callback_cred)
+               return 0;
+       callback_cred = rpc_lookup_machine_cred("nfs");
+       if (!callback_cred)
+               return -ENOMEM;
+       return 0;
+}
+
+struct rpc_cred *get_backchannel_cred(struct nfs4_client *clp, struct rpc_clnt *client, struct nfsd4_session *ses)
+{
+       if (clp->cl_minorversion == 0) {
+               return get_rpccred(callback_cred);
+       } else {
+               struct rpc_auth *auth = client->cl_auth;
+               struct auth_cred acred = {};
+
+               acred.uid = ses->se_cb_sec.uid;
+               acred.gid = ses->se_cb_sec.gid;
+               return auth->au_ops->lookup_cred(client->cl_auth, &acred, 0);
+       }
+}
 
 static int setup_callback_client(struct nfs4_client *clp, struct nfs4_cb_conn *conn, struct nfsd4_session *ses)
 {
@@ -648,6 +673,7 @@ static int setup_callback_client(struct nfs4_client *clp, struct nfs4_cb_conn *c
                .flags          = (RPC_CLNT_CREATE_NOPING | RPC_CLNT_CREATE_QUIET),
        };
        struct rpc_clnt *client;
+       struct rpc_cred *cred;
 
        if (clp->cl_minorversion == 0) {
                if (!clp->cl_cred.cr_principal &&
@@ -675,7 +701,13 @@ static int setup_callback_client(struct nfs4_client *clp, struct nfs4_cb_conn *c
                        PTR_ERR(client));
                return PTR_ERR(client);
        }
+       cred = get_backchannel_cred(clp, client, ses);
+       if (IS_ERR(cred)) {
+               rpc_shutdown_client(client);
+               return PTR_ERR(cred);
+       }
        clp->cl_cb_client = client;
+       clp->cl_cb_cred = cred;
        return 0;
 
 }
@@ -714,18 +746,6 @@ static const struct rpc_call_ops nfsd4_cb_probe_ops = {
        .rpc_call_done = nfsd4_cb_probe_done,
 };
 
-static struct rpc_cred *callback_cred;
-
-int set_callback_cred(void)
-{
-       if (callback_cred)
-               return 0;
-       callback_cred = rpc_lookup_machine_cred("nfs");
-       if (!callback_cred)
-               return -ENOMEM;
-       return 0;
-}
-
 static struct workqueue_struct *callback_wq;
 
 static void run_nfsd4_cb(struct nfsd4_callback *cb)
@@ -743,7 +763,6 @@ static void do_probe_callback(struct nfs4_client *clp)
        cb->cb_msg.rpc_proc = &nfs4_cb_procedures[NFSPROC4_CLNT_CB_NULL];
        cb->cb_msg.rpc_argp = NULL;
        cb->cb_msg.rpc_resp = NULL;
-       cb->cb_msg.rpc_cred = callback_cred;
 
        cb->cb_ops = &nfsd4_cb_probe_ops;
 
@@ -962,6 +981,8 @@ static void nfsd4_process_cb_update(struct nfsd4_callback *cb)
        if (clp->cl_cb_client) {
                rpc_shutdown_client(clp->cl_cb_client);
                clp->cl_cb_client = NULL;
+               put_rpccred(clp->cl_cb_cred);
+               clp->cl_cb_cred = NULL;
        }
        if (clp->cl_cb_conn.cb_xprt) {
                svc_xprt_put(clp->cl_cb_conn.cb_xprt);
@@ -1010,6 +1031,7 @@ void nfsd4_do_callback_rpc(struct work_struct *w)
                nfsd4_release_cb(cb);
                return;
        }
+       cb->cb_msg.rpc_cred = clp->cl_cb_cred;
        rpc_call_async(clnt, &cb->cb_msg, RPC_TASK_SOFT | RPC_TASK_SOFTCONN,
                        cb->cb_ops, cb);
 }
@@ -1025,7 +1047,6 @@ void nfsd4_cb_recall(struct nfs4_delegation *dp)
        cb->cb_msg.rpc_proc = &nfs4_cb_procedures[NFSPROC4_CLNT_CB_RECALL];
        cb->cb_msg.rpc_argp = cb;
        cb->cb_msg.rpc_resp = cb;
-       cb->cb_msg.rpc_cred = callback_cred;
 
        cb->cb_ops = &nfsd4_cb_recall_ops;
 

diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index db7258c..dbbbd2f 100644 (file)
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -957,6 +957,7 @@ void init_session(struct svc_rqst *rqstp, struct nfsd4_session *new, struct nfs4
        new->se_cb_seq_nr = 1;
        new->se_flags = cses->flags;
        new->se_cb_prog = cses->callback_prog;
+       new->se_cb_sec = cses->cb_sec;
        kref_init(&new->se_ref);
        idx = hash_sessionid(&new->se_sessionid);
        spin_lock(&client_lock);

diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h
index df33e78..bff856c 100644 (file)
--- a/fs/nfsd/state.h
+++ b/fs/nfsd/state.h
@@ -250,6 +250,7 @@ struct nfs4_client {
 #define NFSD4_CLIENT_CB_FLAG_MASK      (1 << NFSD4_CLIENT_CB_UPDATE | \
                                         1 << NFSD4_CLIENT_CB_KILL)
        unsigned long           cl_flags;
+       struct rpc_cred         *cl_cb_cred;
        struct rpc_clnt         *cl_cb_client;
        u32                     cl_cb_ident;
 #define NFSD4_CB_UP            0