NFSv4: Introduce new label structure

In order to mimic the way that NFSv4 ACLs are implemented we have created a
structure to be used to pass label data up and down the call chain. This patch
adds the new structure and new members to the required NFSv4 call structures.

Signed-off-by: Matthew N. Dodd <Matthew.Dodd@sparta.com>
Signed-off-by: Miguel Rodel Felipe <Rodel_FM@dsi.a-star.edu.sg>
Signed-off-by: Phua Eu Gene <PHUA_Eu_Gene@dsi.a-star.edu.sg>
Signed-off-by: Khin Mi Mi Aung <Mi_Mi_AUNG@dsi.a-star.edu.sg>
Signed-off-by: Steve Dickson <steved@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

4 files changed, 65 insertions, 0 deletions

diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index c1c7a9d78722..07fcf0b90669 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -257,6 +257,34 @@ nfs_init_locked(struct inode *inode, void *opaque)
         return 0;
 }
 
+#ifdef CONFIG_NFS_V4_SECURITY_LABEL
+struct nfs4_label *nfs4_label_alloc(struct nfs_server *server, gfp_t flags)
+{
+        struct nfs4_label *label = NULL;
+        int minor_version = server->nfs_client->cl_minorversion;
+
+        if (minor_version < 2)
+                return label;
+
+        if (!(server->caps & NFS_CAP_SECURITY_LABEL))
+                return label;
+
+        label = kzalloc(sizeof(struct nfs4_label), flags);
+        if (label == NULL)
+                return ERR_PTR(-ENOMEM);
+
+        label->label = kzalloc(NFS4_MAXLABELLEN, flags);
+        if (label->label == NULL) {
+                kfree(label);
+                return ERR_PTR(-ENOMEM);
+        }
+        label->len = NFS4_MAXLABELLEN;
+
+        return label;
+}
+EXPORT_SYMBOL_GPL(nfs4_label_alloc);
+#endif
+
 /*
  * This is our front-end to iget that looks up inodes by file handle
  * instead of inode number.
diff --git a/include/linux/nfs4.h b/include/linux/nfs4.h
index 42046004a2f6..e36dee52f224 100644
--- a/include/linux/nfs4.h
+++ b/include/linux/nfs4.h
@@ -32,6 +32,15 @@ struct nfs4_acl {
         struct nfs4_ace aces[0];
 };
 
+#define NFS4_MAXLABELLEN        2048
+
+struct nfs4_label {
+        uint32_t        lfs;
+        uint32_t        pi;
+        u32             len;
+        char    *label;
+};
+
 typedef struct { char data[NFS4_VERIFIER_SIZE]; } nfs4_verifier;
 
 struct nfs_stateid4 {
diff --git a/include/linux/nfs_fs.h b/include/linux/nfs_fs.h
index fc01d5cb4cf1..39b24041a4c7 100644
--- a/include/linux/nfs_fs.h
+++ b/include/linux/nfs_fs.h
@@ -497,6 +497,24 @@ extern int nfs_mountpoint_expiry_timeout;
 extern void nfs_release_automount_timer(void);
 
 /*
+ * linux/fs/nfs/nfs4proc.c
+ */
+#ifdef CONFIG_NFS_V4_SECURITY_LABEL
+extern struct nfs4_label *nfs4_label_alloc(struct nfs_server *server, gfp_t flags);
+static inline void nfs4_label_free(struct nfs4_label *label)
+{
+        if (label) {
+                kfree(label->label);
+                kfree(label);
+        }
+        return;
+}
+#else
+static inline struct nfs4_label *nfs4_label_alloc(struct nfs_server *server, gfp_t flags) { return NULL; }
+static inline void nfs4_label_free(void *label) {}
+#endif
+
+/*
  * linux/fs/nfs/unlink.c
  */
 extern void nfs_complete_unlink(struct dentry *dentry, struct inode *);
diff --git a/include/linux/nfs_xdr.h b/include/linux/nfs_xdr.h
index bfdf6e042838..d799b9f86820 100644
--- a/include/linux/nfs_xdr.h
+++ b/include/linux/nfs_xdr.h
@@ -349,6 +349,7 @@ struct nfs_openargs {
         const u32 *             open_bitmap;
         __u32                   claim;
         enum createmode4        createmode;
+        const struct nfs4_label *label;
 };
 
 struct nfs_openres {
@@ -358,6 +359,7 @@ struct nfs_openres {
         struct nfs4_change_info cinfo;
         __u32                   rflags;
         struct nfs_fattr *      f_attr;
+        struct nfs4_label       *f_label;
         struct nfs_seqid *      seqid;
         const struct nfs_server *server;
         fmode_t                 delegation_type;
@@ -600,6 +602,7 @@ struct nfs_entry {
         int                     eof;
         struct nfs_fh *         fh;
         struct nfs_fattr *      fattr;
+        struct nfs4_label  *label;
         unsigned char           d_type;
         struct nfs_server *     server;
 };
@@ -632,6 +635,7 @@ struct nfs_setattrargs {
         struct iattr *                  iap;
         const struct nfs_server *       server; /* Needed for name mapping */
         const u32 *                     bitmask;
+        const struct nfs4_label         *label;
 };
 
 struct nfs_setaclargs {
@@ -667,6 +671,7 @@ struct nfs_getaclres {
 struct nfs_setattrres {
         struct nfs4_sequence_res        seq_res;
         struct nfs_fattr *              fattr;
+        struct nfs4_label               *label;
         const struct nfs_server *       server;
 };
 
@@ -864,6 +869,7 @@ struct nfs4_create_arg {
         const struct iattr *            attrs;
         const struct nfs_fh *           dir_fh;
         const u32 *                     bitmask;
+        const struct nfs4_label         *label;
 };
 
 struct nfs4_create_res {
@@ -871,6 +877,7 @@ struct nfs4_create_res {
         const struct nfs_server *       server;
         struct nfs_fh *                 fh;
         struct nfs_fattr *              fattr;
+        struct nfs4_label               *label;
         struct nfs4_change_info         dir_cinfo;
 };
 
@@ -895,6 +902,7 @@ struct nfs4_getattr_res {
         struct nfs4_sequence_res        seq_res;
         const struct nfs_server *       server;
         struct nfs_fattr *              fattr;
+        struct nfs4_label               *label;
 };
 
 struct nfs4_link_arg {
@@ -909,6 +917,7 @@ struct nfs4_link_res {
         struct nfs4_sequence_res        seq_res;
         const struct nfs_server *       server;
         struct nfs_fattr *              fattr;
+        struct nfs4_label               *label;
         struct nfs4_change_info         cinfo;
         struct nfs_fattr *              dir_attr;
 };
@@ -926,6 +935,7 @@ struct nfs4_lookup_res {
         const struct nfs_server *       server;
         struct nfs_fattr *              fattr;
         struct nfs_fh *                 fh;
+        struct nfs4_label               *label;
 };
 
 struct nfs4_lookup_root_arg {