rpc: pass target name down to rpc level on callbacks

The rpc client needs to know the principal that the setclientid was done
as, so it can tell gssd who to authenticate to.

Signed-off-by: Olga Kornievskaia <aglo@citi.umich.edu>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

3 files changed, 24 insertions, 0 deletions

diff --git a/fs/nfsd/nfs4callback.c b/fs/nfsd/nfs4callback.c
index 094747a1227c..3ca141782145 100644
--- a/fs/nfsd/nfs4callback.c
+++ b/fs/nfsd/nfs4callback.c
@@ -384,6 +384,7 @@ static int do_probe_callback(void *data)
                 .version        = nfs_cb_version[1]->number,
                 .authflavor     = RPC_AUTH_UNIX, /* XXX: need AUTH_GSS... */
                 .flags          = (RPC_CLNT_CREATE_NOPING | RPC_CLNT_CREATE_QUIET),
+                .client_name    = clp->cl_principal,
         };
         struct rpc_message msg = {
                 .rpc_proc       = &nfs4_cb_procedures[NFSPROC4_CLNT_CB_NULL],
@@ -392,6 +393,11 @@ static int do_probe_callback(void *data)
         struct rpc_clnt *client;
         int status;
 
+        if (!clp->cl_principal && (clp->cl_flavor >= RPC_AUTH_GSS_KRB5)) {
+                status = nfserr_cb_path_down;
+                goto out_err;
+        }
+
         /* Initialize address */
         memset(&addr, 0, sizeof(addr));
         addr.sin_family = AF_INET;
diff --git a/include/linux/sunrpc/clnt.h b/include/linux/sunrpc/clnt.h
index 6f0ee1b84a4f..c39a21040dcb 100644
--- a/include/linux/sunrpc/clnt.h
+++ b/include/linux/sunrpc/clnt.h
@@ -58,6 +58,7 @@ struct rpc_clnt {
         struct rpc_timeout      cl_timeout_default;
         struct rpc_program *    cl_program;
         char                    cl_inline_name[32];
+        char                    *cl_principal;  /* target to authenticate to */
 };
 
 /*
@@ -108,6 +109,7 @@ struct rpc_create_args {
         u32                     version;
         rpc_authflavor_t        authflavor;
         unsigned long           flags;
+        char                    *client_name;
 };
 
 /* Values for "flags" field */
diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c
index 4895c341e46d..347f2a25abb6 100644
--- a/net/sunrpc/clnt.c
+++ b/net/sunrpc/clnt.c
@@ -197,6 +197,12 @@ static struct rpc_clnt * rpc_new_client(const struct rpc_create_args *args, stru
 
         clnt->cl_rtt = &clnt->cl_rtt_default;
         rpc_init_rtt(&clnt->cl_rtt_default, clnt->cl_timeout->to_initval);
+        clnt->cl_principal = NULL;
+        if (args->client_name) {
+                clnt->cl_principal = kstrdup(args->client_name, GFP_KERNEL);
+                if (!clnt->cl_principal)
+                        goto out_no_principal;
+        }
 
         kref_init(&clnt->cl_kref);
 
@@ -226,6 +232,8 @@ out_no_auth:
                 rpc_put_mount();
         }
 out_no_path:
+        kfree(clnt->cl_principal);
+out_no_principal:
         rpc_free_iostats(clnt->cl_metrics);
 out_no_stats:
         if (clnt->cl_server != clnt->cl_inline_name)
@@ -354,6 +362,11 @@ rpc_clone_client(struct rpc_clnt *clnt)
         new->cl_metrics = rpc_alloc_iostats(clnt);
         if (new->cl_metrics == NULL)
                 goto out_no_stats;
+        if (clnt->cl_principal) {
+                new->cl_principal = kstrdup(clnt->cl_principal, GFP_KERNEL);
+                if (new->cl_principal == NULL)
+                        goto out_no_principal;
+        }
         kref_init(&new->cl_kref);
         err = rpc_setup_pipedir(new, clnt->cl_program->pipe_dir_name);
         if (err != 0)
@@ -366,6 +379,8 @@ rpc_clone_client(struct rpc_clnt *clnt)
         rpciod_up();
         return new;
 out_no_path:
+        kfree(new->cl_principal);
+out_no_principal:
         rpc_free_iostats(new->cl_metrics);
 out_no_stats:
         kfree(new);
@@ -417,6 +432,7 @@ rpc_free_client(struct kref *kref)
 out_free:
         rpc_unregister_client(clnt);
         rpc_free_iostats(clnt->cl_metrics);
+        kfree(clnt->cl_principal);
         clnt->cl_metrics = NULL;
         xprt_put(clnt->cl_xprt);
         rpciod_down();