[PATCH] NFS: Add support for NFSv3 ACLs
This adds acl support fo nfs clients via the NFSACL protocol extension, by
implementing the getxattr, listxattr, setxattr, and removexattr iops for the
system.posix_acl_access and system.posix_acl_default attributes. This patch
implements a dumb version that uses no caching (and thus adds some overhead).
(Another patch in this patchset adds caching as well.)
Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Acked-by: Olaf Kirch <okir@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/nfs3acl.c b/fs/nfs/nfs3acl.c
new file mode 100644
index 0000000..393ba79
--- /dev/null
+++ b/fs/nfs/nfs3acl.c
@@ -0,0 +1,303 @@
+#include <linux/fs.h>
+#include <linux/nfs.h>
+#include <linux/nfs3.h>
+#include <linux/nfs_fs.h>
+#include <linux/xattr_acl.h>
+#include <linux/nfsacl.h>
+
+#define NFSDBG_FACILITY NFSDBG_PROC
+
+ssize_t nfs3_listxattr(struct dentry *dentry, char *buffer, size_t size)
+{
+ struct inode *inode = dentry->d_inode;
+ struct posix_acl *acl;
+ int pos=0, len=0;
+
+# define output(s) do { \
+ if (pos + sizeof(s) <= size) { \
+ memcpy(buffer + pos, s, sizeof(s)); \
+ pos += sizeof(s); \
+ } \
+ len += sizeof(s); \
+ } while(0)
+
+ acl = nfs3_proc_getacl(inode, ACL_TYPE_ACCESS);
+ if (IS_ERR(acl))
+ return PTR_ERR(acl);
+ if (acl) {
+ output("system.posix_acl_access");
+ posix_acl_release(acl);
+ }
+
+ if (S_ISDIR(inode->i_mode)) {
+ acl = nfs3_proc_getacl(inode, ACL_TYPE_DEFAULT);
+ if (IS_ERR(acl))
+ return PTR_ERR(acl);
+ if (acl) {
+ output("system.posix_acl_default");
+ posix_acl_release(acl);
+ }
+ }
+
+# undef output
+
+ if (!buffer || len <= size)
+ return len;
+ return -ERANGE;
+}
+
+ssize_t nfs3_getxattr(struct dentry *dentry, const char *name,
+ void *buffer, size_t size)
+{
+ struct inode *inode = dentry->d_inode;
+ struct posix_acl *acl;
+ int type, error = 0;
+
+ if (strcmp(name, XATTR_NAME_ACL_ACCESS) == 0)
+ type = ACL_TYPE_ACCESS;
+ else if (strcmp(name, XATTR_NAME_ACL_DEFAULT) == 0)
+ type = ACL_TYPE_DEFAULT;
+ else
+ return -EOPNOTSUPP;
+
+ acl = nfs3_proc_getacl(inode, type);
+ if (IS_ERR(acl))
+ return PTR_ERR(acl);
+ else if (acl) {
+ if (type == ACL_TYPE_ACCESS && acl->a_count == 0)
+ error = -ENODATA;
+ else
+ error = posix_acl_to_xattr(acl, buffer, size);
+ posix_acl_release(acl);
+ } else
+ error = -ENODATA;
+
+ return error;
+}
+
+int nfs3_setxattr(struct dentry *dentry, const char *name,
+ const void *value, size_t size, int flags)
+{
+ struct inode *inode = dentry->d_inode;
+ struct posix_acl *acl;
+ int type, error;
+
+ if (strcmp(name, XATTR_NAME_ACL_ACCESS) == 0)
+ type = ACL_TYPE_ACCESS;
+ else if (strcmp(name, XATTR_NAME_ACL_DEFAULT) == 0)
+ type = ACL_TYPE_DEFAULT;
+ else
+ return -EOPNOTSUPP;
+
+ acl = posix_acl_from_xattr(value, size);
+ if (IS_ERR(acl))
+ return PTR_ERR(acl);
+ error = nfs3_proc_setacl(inode, type, acl);
+ posix_acl_release(acl);
+
+ return error;
+}
+
+int nfs3_removexattr(struct dentry *dentry, const char *name)
+{
+ struct inode *inode = dentry->d_inode;
+ int type;
+
+ if (strcmp(name, XATTR_NAME_ACL_ACCESS) == 0)
+ type = ACL_TYPE_ACCESS;
+ else if (strcmp(name, XATTR_NAME_ACL_DEFAULT) == 0)
+ type = ACL_TYPE_DEFAULT;
+ else
+ return -EOPNOTSUPP;
+
+ return nfs3_proc_setacl(inode, type, NULL);
+}
+
+struct posix_acl *nfs3_proc_getacl(struct inode *inode, int type)
+{
+ struct nfs_server *server = NFS_SERVER(inode);
+ struct nfs_fattr fattr;
+ struct page *pages[NFSACL_MAXPAGES] = { };
+ struct nfs3_getaclargs args = {
+ .fh = NFS_FH(inode),
+ /* The xdr layer may allocate pages here. */
+ .pages = pages,
+ };
+ struct nfs3_getaclres res = {
+ .fattr = &fattr,
+ };
+ struct posix_acl *acl = NULL;
+ int status, count;
+
+ if (!nfs_server_capable(inode, NFS_CAP_ACLS))
+ return ERR_PTR(-EOPNOTSUPP);
+
+ switch (type) {
+ case ACL_TYPE_ACCESS:
+ args.mask = NFS_ACLCNT|NFS_ACL;
+ break;
+
+ case ACL_TYPE_DEFAULT:
+ if (!S_ISDIR(inode->i_mode))
+ return NULL;
+ args.mask = NFS_DFACLCNT|NFS_DFACL;
+ break;
+
+ default:
+ return ERR_PTR(-EINVAL);
+ }
+
+ dprintk("NFS call getacl\n");
+ status = rpc_call(server->client_acl, ACLPROC3_GETACL,
+ &args, &res, 0);
+ dprintk("NFS reply getacl: %d\n", status);
+
+ /* pages may have been allocated at the xdr layer. */
+ for (count = 0; count < NFSACL_MAXPAGES && args.pages[count]; count++)
+ __free_page(args.pages[count]);
+
+ switch (status) {
+ case 0:
+ status = nfs_refresh_inode(inode, &fattr);
+ break;
+ case -EPFNOSUPPORT:
+ case -EPROTONOSUPPORT:
+ dprintk("NFS_V3_ACL extension not supported; disabling\n");
+ server->caps &= ~NFS_CAP_ACLS;
+ case -ENOTSUPP:
+ status = -EOPNOTSUPP;
+ default:
+ goto getout;
+ }
+ if ((args.mask & res.mask) != args.mask) {
+ status = -EIO;
+ goto getout;
+ }
+
+ if (res.acl_access != NULL) {
+ if (posix_acl_equiv_mode(res.acl_access, NULL) == 0) {
+ posix_acl_release(res.acl_access);
+ res.acl_access = NULL;
+ }
+ }
+
+ switch(type) {
+ case ACL_TYPE_ACCESS:
+ acl = res.acl_access;
+ res.acl_access = NULL;
+ break;
+
+ case ACL_TYPE_DEFAULT:
+ acl = res.acl_default;
+ res.acl_default = NULL;
+ }
+
+getout:
+ posix_acl_release(res.acl_access);
+ posix_acl_release(res.acl_default);
+
+ if (status != 0) {
+ posix_acl_release(acl);
+ acl = ERR_PTR(status);
+ }
+ return acl;
+}
+
+static int nfs3_proc_setacls(struct inode *inode, struct posix_acl *acl,
+ struct posix_acl *dfacl)
+{
+ struct nfs_server *server = NFS_SERVER(inode);
+ struct nfs_fattr fattr;
+ struct page *pages[NFSACL_MAXPAGES] = { };
+ struct nfs3_setaclargs args = {
+ .inode = inode,
+ .mask = NFS_ACL,
+ .acl_access = acl,
+ .pages = pages,
+ };
+ int status, count;
+
+ status = -EOPNOTSUPP;
+ if (!nfs_server_capable(inode, NFS_CAP_ACLS))
+ goto out;
+
+ /* We are doing this here, because XDR marshalling can only
+ return -ENOMEM. */
+ status = -ENOSPC;
+ if (acl != NULL && acl->a_count > NFS_ACL_MAX_ENTRIES)
+ goto out;
+ if (dfacl != NULL && dfacl->a_count > NFS_ACL_MAX_ENTRIES)
+ goto out;
+ if (S_ISDIR(inode->i_mode)) {
+ args.mask |= NFS_DFACL;
+ args.acl_default = dfacl;
+ }
+
+ dprintk("NFS call setacl\n");
+ nfs_begin_data_update(inode);
+ status = rpc_call(server->client_acl, ACLPROC3_SETACL,
+ &args, &fattr, 0);
+ NFS_FLAGS(inode) |= NFS_INO_INVALID_ACCESS;
+ nfs_end_data_update(inode);
+ dprintk("NFS reply setacl: %d\n", status);
+
+ /* pages may have been allocated at the xdr layer. */
+ for (count = 0; count < NFSACL_MAXPAGES && args.pages[count]; count++)
+ __free_page(args.pages[count]);
+
+ switch (status) {
+ case 0:
+ status = nfs_refresh_inode(inode, &fattr);
+ break;
+ case -EPFNOSUPPORT:
+ case -EPROTONOSUPPORT:
+ dprintk("NFS_V3_ACL SETACL RPC not supported"
+ "(will not retry)\n");
+ server->caps &= ~NFS_CAP_ACLS;
+ case -ENOTSUPP:
+ status = -EOPNOTSUPP;
+ }
+out:
+ return status;
+}
+
+int nfs3_proc_setacl(struct inode *inode, int type, struct posix_acl *acl)
+{
+ struct posix_acl *alloc = NULL, *dfacl = NULL;
+ int status;
+
+ if (S_ISDIR(inode->i_mode)) {
+ switch(type) {
+ case ACL_TYPE_ACCESS:
+ alloc = dfacl = nfs3_proc_getacl(inode,
+ ACL_TYPE_DEFAULT);
+ if (IS_ERR(alloc))
+ goto fail;
+ break;
+
+ case ACL_TYPE_DEFAULT:
+ dfacl = acl;
+ alloc = acl = nfs3_proc_getacl(inode,
+ ACL_TYPE_ACCESS);
+ if (IS_ERR(alloc))
+ goto fail;
+ break;
+
+ default:
+ return -EINVAL;
+ }
+ } else if (type != ACL_TYPE_ACCESS)
+ return -EINVAL;
+
+ if (acl == NULL) {
+ alloc = acl = posix_acl_from_mode(inode->i_mode, GFP_KERNEL);
+ if (IS_ERR(alloc))
+ goto fail;
+ }
+ status = nfs3_proc_setacls(inode, acl, dfacl);
+ posix_acl_release(alloc);
+ return status;
+
+fail:
+ return PTR_ERR(alloc);
+}
