2010-12-22 21:50:50

by Anna Schumaker

Subject: [PATCH 5/5] NFS: Determine initial mount security

When sec=<something> is not presented as a mount option,
we should attempt to determine what security flavor the
server is using.

Signed-off-by: Bryan Schumaker <[email protected]>
---
fs/nfs/nfs4proc.c | 33 +++++++++++++++++++++++++++++++--
include/linux/sunrpc/gss_api.h | 3 +++
net/sunrpc/auth_gss/gss_mech_switch.c | 16 ++++++++++++++++
3 files changed, 50 insertions(+), 2 deletions(-)

diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 2d4a923..1ea4532 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -41,6 +41,7 @@
#include <linux/string.h>
#include <linux/slab.h>
#include <linux/sunrpc/clnt.h>
+#include <linux/sunrpc/gss_api.h>
#include <linux/nfs.h>
#include <linux/nfs4.h>
#include <linux/nfs_fs.h>
@@ -2141,15 +2142,43 @@ static int nfs4_lookup_root(struct nfs_server *server, struct nfs_fh *fhandle,
return err;
}

+static int nfs4_lookup_root_sec(struct nfs_server *server, struct nfs_fh *fhandle,
+ struct nfs_fsinfo *info, rpc_authflavor_t flavor)
+{
+ struct rpc_auth *auth;
+ int ret;
+
+ auth = rpcauth_create(flavor, server->client);
+ if (!auth) {
+ ret = -EIO;
+ goto out;
+ }
+ ret = nfs4_lookup_root(server, fhandle, info);
+ if (ret < 0)
+ ret = -EAGAIN;
+out:
+ return ret;
+}
+
/*
* get the file handle for the "/" directory on the server
*/
static int nfs4_proc_get_root(struct nfs_server *server, struct nfs_fh *fhandle,
struct nfs_fsinfo *info)
{
- int status;
+ int i, len, status = 0;
+ rpc_authflavor_t flav_array[NFS_MAX_SECFLAVORS + 2];

- status = nfs4_lookup_root(server, fhandle, info);
+ flav_array[0] = RPC_AUTH_UNIX;
+ len = gss_mech_list_pseudoflavors(&flav_array[1]);
+ flav_array[1+len] = RPC_AUTH_NULL;
+ len += 2;
+
+ for (i = 0; i < len; i++) {
+ status = nfs4_lookup_root_sec(server, fhandle, info, flav_array[i]);
+ if (status == 0)
+ break;
+ }
if (status == 0)
status = nfs4_server_capabilities(server, fhandle);
if (status == 0)
diff --git a/include/linux/sunrpc/gss_api.h b/include/linux/sunrpc/gss_api.h
index 5d8048b..332da61 100644
--- a/include/linux/sunrpc/gss_api.h
+++ b/include/linux/sunrpc/gss_api.h
@@ -126,6 +126,9 @@ struct gss_api_mech *gss_mech_get_by_name(const char *);
/* Similar, but get by pseudoflavor. */
struct gss_api_mech *gss_mech_get_by_pseudoflavor(u32);

+/* Fill in an array with a list of supported pseudoflavors */
+int gss_mech_list_pseudoflavors(u32 *);
+
/* Just increments the mechanism's reference count and returns its input: */
struct gss_api_mech * gss_mech_get(struct gss_api_mech *);

diff --git a/net/sunrpc/auth_gss/gss_mech_switch.c b/net/sunrpc/auth_gss/gss_mech_switch.c
index 6c844b0..e3c36a2 100644
--- a/net/sunrpc/auth_gss/gss_mech_switch.c
+++ b/net/sunrpc/auth_gss/gss_mech_switch.c
@@ -215,6 +215,22 @@ gss_mech_get_by_pseudoflavor(u32 pseudoflavor)

EXPORT_SYMBOL_GPL(gss_mech_get_by_pseudoflavor);

+int gss_mech_list_pseudoflavors(rpc_authflavor_t *array_ptr)
+{
+ struct gss_api_mech *pos = NULL;
+ int i = 0;
+
+ spin_lock(&registered_mechs_lock);
+ list_for_each_entry(pos, &registered_mechs, gm_list) {
+ array_ptr[i] = pos->gm_pfs->pseudoflavor;
+ i++;
+ }
+ spin_unlock(&registered_mechs_lock);
+ return i;
+}
+
+EXPORT_SYMBOL_GPL(gss_mech_list_pseudoflavors);
+
u32
gss_svc_to_pseudoflavor(struct gss_api_mech *gm, u32 service)
{
--
1.7.3.4