NFS: Client implementation of Labeled-NFS

This patch implements the client transport and handling support for labeled
NFS. The patch adds two functions to encode and decode the security label
recommended attribute which makes use of the LSM hooks added earlier. It also
adds code to grab the label from the file attribute structures and encode the
label to be sent back to the server.

Acked-by: James Morris <james.l.morris@oracle.com>
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>

1 files changed, 54 insertions, 7 deletions

diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index 12e8ad85ae50..f908af672197 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -162,11 +162,19 @@ static void nfs_zap_caches_locked(struct inode *inode)
 
 	memset(NFS_I(inode)->cookieverf, 0, sizeof(NFS_I(inode)->cookieverf));
 	if (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode)) {
-		nfsi->cache_validity |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_DATA|NFS_INO_INVALID_ACCESS|NFS_INO_INVALID_ACL|NFS_INO_REVAL_PAGECACHE;
 		nfs_fscache_invalidate(inode);
-	} else {
-		nfsi->cache_validity |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_ACCESS|NFS_INO_INVALID_ACL|NFS_INO_REVAL_PAGECACHE;
-	}
+		nfsi->cache_validity |= NFS_INO_INVALID_ATTR
+					| NFS_INO_INVALID_LABEL
+					| NFS_INO_INVALID_DATA
+					| NFS_INO_INVALID_ACCESS
+					| NFS_INO_INVALID_ACL
+					| NFS_INO_REVAL_PAGECACHE;
+	} else
+		nfsi->cache_validity |= NFS_INO_INVALID_ATTR
+					| NFS_INO_INVALID_LABEL
+					| NFS_INO_INVALID_ACCESS
+					| NFS_INO_INVALID_ACL
+					| NFS_INO_REVAL_PAGECACHE;
 }
 
 void nfs_zap_caches(struct inode *inode)
@@ -258,6 +266,32 @@ nfs_init_locked(struct inode *inode, void *opaque)
 }
 
 #ifdef CONFIG_NFS_V4_SECURITY_LABEL
+void nfs_setsecurity(struct inode *inode, struct nfs_fattr *fattr,
+					struct nfs4_label *label)
+{
+	int error;
+
+	if (label == NULL)
+		return;
+
+	if (nfs_server_capable(inode, NFS_CAP_SECURITY_LABEL) == 0)
+		return;
+
+	if (NFS_SERVER(inode)->nfs_client->cl_minorversion < 2)
+		return;
+
+	if ((fattr->valid & NFS_ATTR_FATTR_V4_SECURITY_LABEL) && inode->i_security) {
+		error = security_inode_notifysecctx(inode, label->label,
+				label->len);
+		if (error)
+			printk(KERN_ERR "%s() %s %d "
+					"security_inode_notifysecctx() %d\n",
+					__func__,
+					(char *)label->label,
+					label->len, error);
+	}
+}
+
 struct nfs4_label *nfs4_label_alloc(struct nfs_server *server, gfp_t flags)
 {
 	struct nfs4_label *label = NULL;
@@ -283,7 +317,13 @@ struct nfs4_label *nfs4_label_alloc(struct nfs_server *server, gfp_t flags)
 	return label;
 }
 EXPORT_SYMBOL_GPL(nfs4_label_alloc);
+#else
+void inline nfs_setsecurity(struct inode *inode, struct nfs_fattr *fattr,
+					struct nfs4_label *label)
+{
+}
 #endif
+EXPORT_SYMBOL_GPL(nfs_setsecurity);
 
 /*
  * This is our front-end to iget that looks up inodes by file handle
@@ -412,6 +452,9 @@ nfs_fhget(struct super_block *sb, struct nfs_fh *fh, struct nfs_fattr *fattr, st
 			 */
 			inode->i_blocks = nfs_calc_block_size(fattr->du.nfs3.used);
 		}
+
+		nfs_setsecurity(inode, fattr, label);
+
 		nfsi->attrtimeo = NFS_MINATTRTIMEO(inode);
 		nfsi->attrtimeo_timestamp = now;
 		nfsi->access_cache = RB_ROOT;
@@ -421,6 +464,7 @@ nfs_fhget(struct super_block *sb, struct nfs_fh *fh, struct nfs_fattr *fattr, st
 		unlock_new_inode(inode);
 	} else
 		nfs_refresh_inode(inode, fattr);
+		nfs_setsecurity(inode, fattr, label);
 	dprintk("NFS: nfs_fhget(%s/%Ld fh_crc=0x%08x ct=%d)\n",
 		inode->i_sb->s_id,
 		(long long)NFS_FILEID(inode),
@@ -477,7 +521,7 @@ nfs_setattr(struct dentry *dentry, struct iattr *attr)
 		NFS_PROTO(inode)->return_delegation(inode);
 	error = NFS_PROTO(inode)->setattr(dentry, fattr, attr);
 	if (error == 0)
-		nfs_refresh_inode(inode, fattr);
+		error = nfs_refresh_inode(inode, fattr);
 	nfs_free_fattr(fattr);
 out:
 	return error;
@@ -901,7 +945,8 @@ static int nfs_attribute_cache_expired(struct inode *inode)
  */
 int nfs_revalidate_inode(struct nfs_server *server, struct inode *inode)
 {
-	if (!(NFS_I(inode)->cache_validity & NFS_INO_INVALID_ATTR)
+	if (!(NFS_I(inode)->cache_validity &
+			(NFS_INO_INVALID_ATTR|NFS_INO_INVALID_LABEL))
 			&& !nfs_attribute_cache_expired(inode))
 		return NFS_STALE(inode) ? -ESTALE : 0;
 	return __nfs_revalidate_inode(server, inode);
@@ -1281,6 +1326,7 @@ int nfs_post_op_update_inode(struct inode *inode, struct nfs_fattr *fattr)
 	spin_lock(&inode->i_lock);
 	status = nfs_post_op_update_inode_locked(inode, fattr);
 	spin_unlock(&inode->i_lock);
+
 	return status;
 }
 EXPORT_SYMBOL_GPL(nfs_post_op_update_inode);
@@ -1521,7 +1567,7 @@ static int nfs_update_inode(struct inode *inode, struct nfs_fattr *fattr)
 		inode->i_blocks = fattr->du.nfs2.blocks;
 
 	/* Update attrtimeo value if we're out of the unstable period */
-	if (invalid & NFS_INO_INVALID_ATTR) {
+	if (invalid & (NFS_INO_INVALID_ATTR|NFS_INO_INVALID_LABEL)) {
 		nfs_inc_stats(inode, NFSIOS_ATTRINVALIDATE);
 		nfsi->attrtimeo = NFS_MINATTRTIMEO(inode);
 		nfsi->attrtimeo_timestamp = now;
@@ -1534,6 +1580,7 @@ static int nfs_update_inode(struct inode *inode, struct nfs_fattr *fattr)
 		}
 	}
 	invalid &= ~NFS_INO_INVALID_ATTR;
+	invalid &= ~NFS_INO_INVALID_LABEL;
 	/* Don't invalidate the data if we were to blame */
 	if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode)
 				|| S_ISLNK(inode->i_mode)))