[PATCH] NFSD: Add server support for NFSv3 ACLs.

This adds functions for encoding and decoding POSIX ACLs for the NFSACL
protocol extension, and the GETACL and SETACL RPCs. The implementation is
compatible with NFSACL in Solaris.

Signed-off-by: Andreas Gruenbacher <[e-mail]>
Acked-by: Olaf Kirch <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Signed-off-by: Trond Myklebust <[e-mail]>

fs/Kconfig

···
 	select LOCKD
 	select SUNRPC
 	select EXPORTFS
+	select NFS_ACL_SUPPORT if NFSD_V3_ACL || NFSD_V2_ACL
 	help
 	  If you want your Linux box to act as an NFS *server*, so that other
 	  computers on your local network which support NFS can access certain
···
 	  To compile the NFS server support as a module, choose M here: the
 	  module will be called nfsd.  If unsure, say N.
 
+config NFSD_V2_ACL
+	bool
+	depends on NFSD
+
 config NFSD_V3
 	bool "Provide NFSv3 server support"
 	depends on NFSD
 	help
 	  If you would like to include the NFSv3 server as well as the NFSv2
 	  server, say Y here.  If unsure, say Y.
+
+config NFSD_V3_ACL
+	bool "Provide server support for the NFSv3 ACL protocol extension"
+	depends on NFSD_V3
+	select NFSD_V2_ACL
+	help
+	  Implement the NFSv3 ACL protocol extension for manipulating POSIX
+	  Access Control Lists on exported file systems. NFS clients should
+	  be compiled with the NFSv3 ACL protocol extension; see the
+	  CONFIG_NFS_V3_ACL option.  If unsure, say N.
 
 config NFSD_V4
 	bool "Provide NFSv4 server support (EXPERIMENTAL)"
···
 
 config EXPORTFS
 	tristate
+
+config NFS_ACL_SUPPORT
+	tristate
+	select FS_POSIX_ACL
+
+config NFS_COMMON
+	bool
+	depends on NFSD || NFS_FS
+	default y
 
 config SUNRPC
 	tristate

fs/Makefile

···
 
 obj-$(CONFIG_FS_MBCACHE)	+= mbcache.o
 obj-$(CONFIG_FS_POSIX_ACL)	+= posix_acl.o xattr_acl.o
+obj-$(CONFIG_NFS_COMMON)	+= nfs_common/
 
 obj-$(CONFIG_QUOTA)		+= dquot.o
 obj-$(CONFIG_QFMT_V1)		+= quota_v1.o

fs/nfs_common/Makefile

···
+#
+# Makefile for Linux filesystem routines that are shared by client and server.
+#
+
+obj-$(CONFIG_NFS_ACL_SUPPORT) += nfs_acl.o
+
+nfs_acl-objs := nfsacl.o

fs/nfs_common/nfsacl.c

···
+/*
+ * fs/nfs_common/nfsacl.c
+ *
+ *  Copyright (C) 2002-2003 Andreas Gruenbacher <[e-mail]>
+ */
+
+/*
+ * The Solaris nfsacl protocol represents some ACLs slightly differently
+ * than POSIX 1003.1e draft 17 does (and we do):
+ *
+ *  - Minimal ACLs always have an ACL_MASK entry, so they have
+ *    four instead of three entries.
+ *  - The ACL_MASK entry in such minimal ACLs always has the same
+ *    permissions as the ACL_GROUP_OBJ entry. (In extended ACLs
+ *    the ACL_MASK and ACL_GROUP_OBJ entries may differ.)
+ *  - The identifier fields of the ACL_USER_OBJ and ACL_GROUP_OBJ
+ *    entries contain the identifiers of the owner and owning group.
+ *    (In POSIX ACLs we always set them to ACL_UNDEFINED_ID).
+ *  - ACL entries in the kernel are kept sorted in ascending order
+ *    of (e_tag, e_id). Solaris ACLs are unsorted.
+ */
+
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <linux/sunrpc/xdr.h>
+#include <linux/nfsacl.h>
+#include <linux/nfs3.h>
+#include <linux/sort.h>
+
+MODULE_LICENSE("GPL");
+
+EXPORT_SYMBOL(nfsacl_encode);
+EXPORT_SYMBOL(nfsacl_decode);
+
+struct nfsacl_encode_desc {
+	struct xdr_array2_desc desc;
+	unsigned int count;
+	struct posix_acl *acl;
+	int typeflag;
+	uid_t uid;
+	gid_t gid;
+};
+
+static int
+xdr_nfsace_encode(struct xdr_array2_desc *desc, void *elem)
+{
+	struct nfsacl_encode_desc *nfsacl_desc =
+		(struct nfsacl_encode_desc *) desc;
+	u32 *p = (u32 *) elem;
+
+	if (nfsacl_desc->count < nfsacl_desc->acl->a_count) {
+		struct posix_acl_entry *entry =
+			&nfsacl_desc->acl->a_entries[nfsacl_desc->count++];
+
+		*p++ = htonl(entry->e_tag | nfsacl_desc->typeflag);
+		switch(entry->e_tag) {
+			case ACL_USER_OBJ:
+				*p++ = htonl(nfsacl_desc->uid);
+				break;
+			case ACL_GROUP_OBJ:
+				*p++ = htonl(nfsacl_desc->gid);
+				break;
+			case ACL_USER:
+			case ACL_GROUP:
+				*p++ = htonl(entry->e_id);
+				break;
+			default:  /* Solaris depends on that! */
+				*p++ = 0;
+				break;
+		}
+		*p++ = htonl(entry->e_perm & S_IRWXO);
+	} else {
+		const struct posix_acl_entry *pa, *pe;
+		int group_obj_perm = ACL_READ|ACL_WRITE|ACL_EXECUTE;
+
+		FOREACH_ACL_ENTRY(pa, nfsacl_desc->acl, pe) {
+			if (pa->e_tag == ACL_GROUP_OBJ) {
+				group_obj_perm = pa->e_perm & S_IRWXO;
+				break;
+			}
+		}
+		/* fake up ACL_MASK entry */
+		*p++ = htonl(ACL_MASK | nfsacl_desc->typeflag);
+		*p++ = htonl(0);
+		*p++ = htonl(group_obj_perm);
+	}
+
+	return 0;
+}
+
+unsigned int
+nfsacl_encode(struct xdr_buf *buf, unsigned int base, struct inode *inode,
+	      struct posix_acl *acl, int encode_entries, int typeflag)
+{
+	int entries = (acl && acl->a_count) ? max_t(int, acl->a_count, 4) : 0;
+	struct nfsacl_encode_desc nfsacl_desc = {
+		.desc = {
+			.elem_size = 12,
+			.array_len = encode_entries ? entries : 0,
+			.xcode = xdr_nfsace_encode,
+		},
+		.acl = acl,
+		.typeflag = typeflag,
+		.uid = inode->i_uid,
+		.gid = inode->i_gid,
+	};
+	int err;
+
+	if (entries > NFS_ACL_MAX_ENTRIES ||
+	    xdr_encode_word(buf, base, entries))
+		return -EINVAL;
+	err = xdr_encode_array2(buf, base + 4, &nfsacl_desc.desc);
+	if (!err)
+		err = 8 + nfsacl_desc.desc.elem_size *
+			  nfsacl_desc.desc.array_len;
+	return err;
+}
+
+struct nfsacl_decode_desc {
+	struct xdr_array2_desc desc;
+	unsigned int count;
+	struct posix_acl *acl;
+};
+
+static int
+xdr_nfsace_decode(struct xdr_array2_desc *desc, void *elem)
+{
+	struct nfsacl_decode_desc *nfsacl_desc =
+		(struct nfsacl_decode_desc *) desc;
+	u32 *p = (u32 *) elem;
+	struct posix_acl_entry *entry;
+
+	if (!nfsacl_desc->acl) {
+		if (desc->array_len > NFS_ACL_MAX_ENTRIES)
+			return -EINVAL;
+		nfsacl_desc->acl = posix_acl_alloc(desc->array_len, GFP_KERNEL);
+		if (!nfsacl_desc->acl)
+			return -ENOMEM;
+		nfsacl_desc->count = 0;
+	}
+
+	entry = &nfsacl_desc->acl->a_entries[nfsacl_desc->count++];
+	entry->e_tag = ntohl(*p++) & ~NFS_ACL_DEFAULT;
+	entry->e_id = ntohl(*p++);
+	entry->e_perm = ntohl(*p++);
+
+	switch(entry->e_tag) {
+		case ACL_USER_OBJ:
+		case ACL_USER:
+		case ACL_GROUP_OBJ:
+		case ACL_GROUP:
+		case ACL_OTHER:
+			if (entry->e_perm & ~S_IRWXO)
+				return -EINVAL;
+			break;
+		case ACL_MASK:
+			/* Solaris sometimes sets additonal bits in the mask */
+			entry->e_perm &= S_IRWXO;
+			break;
+		default:
+			return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int
+cmp_acl_entry(const void *x, const void *y)
+{
+	const struct posix_acl_entry *a = x, *b = y;
+
+	if (a->e_tag != b->e_tag)
+		return a->e_tag - b->e_tag;
+	else if (a->e_id > b->e_id)
+		return 1;
+	else if (a->e_id < b->e_id)
+		return -1;
+	else
+		return 0;
+}
+
+/*
+ * Convert from a Solaris ACL to a POSIX 1003.1e draft 17 ACL.
+ */
+static int
+posix_acl_from_nfsacl(struct posix_acl *acl)
+{
+	struct posix_acl_entry *pa, *pe,
+	       *group_obj = NULL, *mask = NULL;
+
+	if (!acl)
+		return 0;
+
+	sort(acl->a_entries, acl->a_count, sizeof(struct posix_acl_entry),
+	     cmp_acl_entry, NULL);
+
+	/* Clear undefined identifier fields and find the ACL_GROUP_OBJ
+	   and ACL_MASK entries. */
+	FOREACH_ACL_ENTRY(pa, acl, pe) {
+		switch(pa->e_tag) {
+			case ACL_USER_OBJ:
+				pa->e_id = ACL_UNDEFINED_ID;
+				break;
+			case ACL_GROUP_OBJ:
+				pa->e_id = ACL_UNDEFINED_ID;
+				group_obj = pa;
+				break;
+			case ACL_MASK:
+				mask = pa;
+				/* fall through */
+			case ACL_OTHER:
+				pa->e_id = ACL_UNDEFINED_ID;
+				break;
+		}
+	}
+	if (acl->a_count == 4 && group_obj && mask &&
+	    mask->e_perm == group_obj->e_perm) {
+		/* remove bogus ACL_MASK entry */
+		memmove(mask, mask+1, (3 - (mask - acl->a_entries)) *
+				      sizeof(struct posix_acl_entry));
+		acl->a_count = 3;
+	}
+	return 0;
+}
+
+unsigned int
+nfsacl_decode(struct xdr_buf *buf, unsigned int base, unsigned int *aclcnt,
+	      struct posix_acl **pacl)
+{
+	struct nfsacl_decode_desc nfsacl_desc = {
+		.desc = {
+			.elem_size = 12,
+			.xcode = pacl ? xdr_nfsace_decode : NULL,
+		},
+	};
+	u32 entries;
+	int err;
+
+	if (xdr_decode_word(buf, base, &entries) ||
+	    entries > NFS_ACL_MAX_ENTRIES)
+		return -EINVAL;
+	err = xdr_decode_array2(buf, base + 4, &nfsacl_desc.desc);
+	if (err)
+		return err;
+	if (pacl) {
+		if (entries != nfsacl_desc.desc.array_len ||
+		    posix_acl_from_nfsacl(nfsacl_desc.acl) != 0) {
+			posix_acl_release(nfsacl_desc.acl);
+			return -EINVAL;
+		}
+		*pacl = nfsacl_desc.acl;
+	}
+	if (aclcnt)
+		*aclcnt = entries;
+	return 8 + nfsacl_desc.desc.elem_size *
+		   nfsacl_desc.desc.array_len;
+}

fs/nfsd/Makefile

···
 
 nfsd-y 			:= nfssvc.o nfsctl.o nfsproc.o nfsfh.o vfs.o \
 			   export.o auth.o lockd.o nfscache.o nfsxdr.o stats.o
+nfsd-$(CONFIG_NFSD_V2_ACL) += nfs2acl.o
 nfsd-$(CONFIG_NFSD_V3)	+= nfs3proc.o nfs3xdr.o
+nfsd-$(CONFIG_NFSD_V3_ACL) += nfs3acl.o
 nfsd-$(CONFIG_NFSD_V4)	+= nfs4proc.o nfs4xdr.o nfs4state.o nfs4idmap.o \
 			   nfs4acl.o nfs4callback.o
 nfsd-objs		:= $(nfsd-y)

fs/nfsd/nfs2acl.c

···
+/*
+ * linux/fs/nfsd/nfsacl.c
+ *
+ * Process version 2 NFSACL requests.
+ *
+ * Copyright (C) 2002-2003 Andreas Gruenbacher <[e-mail]>
+ */
+
+#include <linux/sunrpc/svc.h>
+#include <linux/nfs.h>
+#include <linux/nfsd/nfsd.h>
+#include <linux/nfsd/cache.h>
+#include <linux/nfsd/xdr.h>
+#include <linux/nfsd/xdr3.h>
+#include <linux/posix_acl.h>
+#include <linux/nfsacl.h>
+
+#define NFSDDBG_FACILITY		NFSDDBG_PROC
+#define RETURN_STATUS(st)	{ resp->status = (st); return (st); }
+
+/*
+ * NULL call.
+ */
+static int
+nfsacld_proc_null(struct svc_rqst *rqstp, void *argp, void *resp)
+{
+	return nfs_ok;
+}
+
+/*
+ * Get the Access and/or Default ACL of a file.
+ */
+static int nfsacld_proc_getacl(struct svc_rqst * rqstp,
+		struct nfsd3_getaclargs *argp, struct nfsd3_getaclres *resp)
+{
+	svc_fh *fh;
+	struct posix_acl *acl;
+	int nfserr = 0;
+
+	dprintk("nfsd: GETACL(2acl)   %s\n", SVCFH_fmt(&argp->fh));
+
+	fh = fh_copy(&resp->fh, &argp->fh);
+	if ((nfserr = fh_verify(rqstp, &resp->fh, 0, MAY_NOP)))
+		RETURN_STATUS(nfserr_inval);
+
+	if (argp->mask & ~(NFS_ACL|NFS_ACLCNT|NFS_DFACL|NFS_DFACLCNT))
+		RETURN_STATUS(nfserr_inval);
+	resp->mask = argp->mask;
+
+	if (resp->mask & (NFS_ACL|NFS_ACLCNT)) {
+		acl = nfsd_get_posix_acl(fh, ACL_TYPE_ACCESS);
+		if (IS_ERR(acl)) {
+			int err = PTR_ERR(acl);
+
+			if (err == -ENODATA || err == -EOPNOTSUPP)
+				acl = NULL;
+			else {
+				nfserr = nfserrno(err);
+				goto fail;
+			}
+		}
+		if (acl == NULL) {
+			/* Solaris returns the inode's minimum ACL. */
+
+			struct inode *inode = fh->fh_dentry->d_inode;
+			acl = posix_acl_from_mode(inode->i_mode, GFP_KERNEL);
+		}
+		resp->acl_access = acl;
+	}
+	if (resp->mask & (NFS_DFACL|NFS_DFACLCNT)) {
+		/* Check how Solaris handles requests for the Default ACL
+		   of a non-directory! */
+
+		acl = nfsd_get_posix_acl(fh, ACL_TYPE_DEFAULT);
+		if (IS_ERR(acl)) {
+			int err = PTR_ERR(acl);
+
+			if (err == -ENODATA || err == -EOPNOTSUPP)
+				acl = NULL;
+			else {
+				nfserr = nfserrno(err);
+				goto fail;
+			}
+		}
+		resp->acl_default = acl;
+	}
+
+	/* resp->acl_{access,default} are released in nfssvc_release_getacl. */
+	RETURN_STATUS(0);
+
+fail:
+	posix_acl_release(resp->acl_access);
+	posix_acl_release(resp->acl_default);
+	RETURN_STATUS(nfserr);
+}
+
+/*
+ * Set the Access and/or Default ACL of a file.
+ */
+static int nfsacld_proc_setacl(struct svc_rqst * rqstp,
+		struct nfsd3_setaclargs *argp,
+		struct nfsd_attrstat *resp)
+{
+	svc_fh *fh;
+	int nfserr = 0;
+
+	dprintk("nfsd: SETACL(2acl)   %s\n", SVCFH_fmt(&argp->fh));
+
+	fh = fh_copy(&resp->fh, &argp->fh);
+	nfserr = fh_verify(rqstp, &resp->fh, 0, MAY_NOP);
+
+	if (!nfserr) {
+		nfserr = nfserrno( nfsd_set_posix_acl(
+			fh, ACL_TYPE_ACCESS, argp->acl_access) );
+	}
+	if (!nfserr) {
+		nfserr = nfserrno( nfsd_set_posix_acl(
+			fh, ACL_TYPE_DEFAULT, argp->acl_default) );
+	}
+
+	/* argp->acl_{access,default} may have been allocated in
+	   nfssvc_decode_setaclargs. */
+	posix_acl_release(argp->acl_access);
+	posix_acl_release(argp->acl_default);
+	return nfserr;
+}
+
+/*
+ * Check file attributes
+ */
+static int nfsacld_proc_getattr(struct svc_rqst * rqstp,
+		struct nfsd_fhandle *argp, struct nfsd_attrstat *resp)
+{
+	dprintk("nfsd: GETATTR  %s\n", SVCFH_fmt(&argp->fh));
+
+	fh_copy(&resp->fh, &argp->fh);
+	return fh_verify(rqstp, &resp->fh, 0, MAY_NOP);
+}
+
+/*
+ * Check file access
+ */
+static int nfsacld_proc_access(struct svc_rqst *rqstp, struct nfsd3_accessargs *argp,
+		struct nfsd3_accessres *resp)
+{
+	int nfserr;
+
+	dprintk("nfsd: ACCESS(2acl)   %s 0x%x\n",
+			SVCFH_fmt(&argp->fh),
+			argp->access);
+
+	fh_copy(&resp->fh, &argp->fh);
+	resp->access = argp->access;
+	nfserr = nfsd_access(rqstp, &resp->fh, &resp->access, NULL);
+	return nfserr;
+}
+
+/*
+ * XDR decode functions
+ */
+static int nfsaclsvc_decode_getaclargs(struct svc_rqst *rqstp, u32 *p,
+		struct nfsd3_getaclargs *argp)
+{
+	if (!(p = nfs2svc_decode_fh(p, &argp->fh)))
+		return 0;
+	argp->mask = ntohl(*p); p++;
+
+	return xdr_argsize_check(rqstp, p);
+}
+
+
+static int nfsaclsvc_decode_setaclargs(struct svc_rqst *rqstp, u32 *p,
+		struct nfsd3_setaclargs *argp)
+{
+	struct kvec *head = rqstp->rq_arg.head;
+	unsigned int base;
+	int n;
+
+	if (!(p = nfs2svc_decode_fh(p, &argp->fh)))
+		return 0;
+	argp->mask = ntohl(*p++);
+	if (argp->mask & ~(NFS_ACL|NFS_ACLCNT|NFS_DFACL|NFS_DFACLCNT) ||
+	    !xdr_argsize_check(rqstp, p))
+		return 0;
+
+	base = (char *)p - (char *)head->iov_base;
+	n = nfsacl_decode(&rqstp->rq_arg, base, NULL,
+			  (argp->mask & NFS_ACL) ?
+			  &argp->acl_access : NULL);
+	if (n > 0)
+		n = nfsacl_decode(&rqstp->rq_arg, base + n, NULL,
+				  (argp->mask & NFS_DFACL) ?
+				  &argp->acl_default : NULL);
+	return (n > 0);
+}
+
+static int nfsaclsvc_decode_fhandleargs(struct svc_rqst *rqstp, u32 *p,
+		struct nfsd_fhandle *argp)
+{
+	if (!(p = nfs2svc_decode_fh(p, &argp->fh)))
+		return 0;
+	return xdr_argsize_check(rqstp, p);
+}
+
+static int nfsaclsvc_decode_accessargs(struct svc_rqst *rqstp, u32 *p,
+		struct nfsd3_accessargs *argp)
+{
+	if (!(p = nfs2svc_decode_fh(p, &argp->fh)))
+		return 0;
+	argp->access = ntohl(*p++);
+
+	return xdr_argsize_check(rqstp, p);
+}
+
+/*
+ * XDR encode functions
+ */
+
+/* GETACL */
+static int nfsaclsvc_encode_getaclres(struct svc_rqst *rqstp, u32 *p,
+		struct nfsd3_getaclres *resp)
+{
+	struct dentry *dentry = resp->fh.fh_dentry;
+	struct inode *inode = dentry->d_inode;
+	int w = nfsacl_size(
+		(resp->mask & NFS_ACL)   ? resp->acl_access  : NULL,
+		(resp->mask & NFS_DFACL) ? resp->acl_default : NULL);
+	struct kvec *head = rqstp->rq_res.head;
+	unsigned int base;
+	int n;
+
+	if (dentry == NULL || dentry->d_inode == NULL)
+		return 0;
+	inode = dentry->d_inode;
+
+	p = nfs2svc_encode_fattr(rqstp, p, &resp->fh);
+	*p++ = htonl(resp->mask);
+	if (!xdr_ressize_check(rqstp, p))
+		return 0;
+	base = (char *)p - (char *)head->iov_base;
+
+	rqstp->rq_res.page_len = w;
+	while (w > 0) {
+		if (!svc_take_res_page(rqstp))
+			return 0;
+		w -= PAGE_SIZE;
+	}
+
+	n = nfsacl_encode(&rqstp->rq_res, base, inode,
+			  resp->acl_access,
+			  resp->mask & NFS_ACL, 0);
+	if (n > 0)
+		n = nfsacl_encode(&rqstp->rq_res, base + n, inode,
+				  resp->acl_default,
+				  resp->mask & NFS_DFACL,
+				  NFS_ACL_DEFAULT);
+	if (n <= 0)
+		return 0;
+	return 1;
+}
+
+static int nfsaclsvc_encode_attrstatres(struct svc_rqst *rqstp, u32 *p,
+		struct nfsd_attrstat *resp)
+{
+	p = nfs2svc_encode_fattr(rqstp, p, &resp->fh);
+	return xdr_ressize_check(rqstp, p);
+}
+
+/* ACCESS */
+static int nfsaclsvc_encode_accessres(struct svc_rqst *rqstp, u32 *p,
+		struct nfsd3_accessres *resp)
+{
+	p = nfs2svc_encode_fattr(rqstp, p, &resp->fh);
+	*p++ = htonl(resp->access);
+	return xdr_ressize_check(rqstp, p);
+}
+
+/*
+ * XDR release functions
+ */
+static int nfsaclsvc_release_getacl(struct svc_rqst *rqstp, u32 *p,
+		struct nfsd3_getaclres *resp)
+{
+	fh_put(&resp->fh);
+	posix_acl_release(resp->acl_access);
+	posix_acl_release(resp->acl_default);
+	return 1;
+}
+
+static int nfsaclsvc_release_fhandle(struct svc_rqst *rqstp, u32 *p,
+		struct nfsd_fhandle *resp)
+{
+	fh_put(&resp->fh);
+	return 1;
+}
+
+#define nfsaclsvc_decode_voidargs	NULL
+#define nfsaclsvc_encode_voidres	NULL
+#define nfsaclsvc_release_void		NULL
+#define nfsd3_fhandleargs	nfsd_fhandle
+#define nfsd3_attrstatres	nfsd_attrstat
+#define nfsd3_voidres		nfsd3_voidargs
+struct nfsd3_voidargs { int dummy; };
+
+#define PROC(name, argt, rest, relt, cache, respsize)	\
+ { (svc_procfunc) nfsacld_proc_##name,		\
+   (kxdrproc_t) nfsaclsvc_decode_##argt##args,	\
+   (kxdrproc_t) nfsaclsvc_encode_##rest##res,	\
+   (kxdrproc_t) nfsaclsvc_release_##relt,		\
+   sizeof(struct nfsd3_##argt##args),		\
+   sizeof(struct nfsd3_##rest##res),		\
+   0,						\
+   cache,					\
+   respsize,					\
+ }
+
+#define ST 1		/* status*/
+#define AT 21		/* attributes */
+#define pAT (1+AT)	/* post attributes - conditional */
+#define ACL (1+NFS_ACL_MAX_ENTRIES*3)  /* Access Control List */
+
+static struct svc_procedure		nfsd_acl_procedures2[] = {
+  PROC(null,	void,		void,		void,	  RC_NOCACHE, ST),
+  PROC(getacl,	getacl,		getacl,		getacl,	  RC_NOCACHE, ST+1+2*(1+ACL)),
+  PROC(setacl,	setacl,		attrstat,	fhandle,  RC_NOCACHE, ST+AT),
+  PROC(getattr, fhandle,	attrstat,	fhandle,  RC_NOCACHE, ST+AT),
+  PROC(access,	access,		access,		fhandle,  RC_NOCACHE, ST+AT+1),
+};
+
+struct svc_version	nfsd_acl_version2 = {
+		.vs_vers	= 2,
+		.vs_nproc	= 5,
+		.vs_proc	= nfsd_acl_procedures2,
+		.vs_dispatch	= nfsd_dispatch,
+		.vs_xdrsize	= NFS3_SVC_XDRSIZE,
+};

fs/nfsd/nfs3acl.c

···
+/*
+ * linux/fs/nfsd/nfs3acl.c
+ *
+ * Process version 3 NFSACL requests.
+ *
+ * Copyright (C) 2002-2003 Andreas Gruenbacher <[e-mail]>
+ */
+
+#include <linux/sunrpc/svc.h>
+#include <linux/nfs3.h>
+#include <linux/nfsd/nfsd.h>
+#include <linux/nfsd/cache.h>
+#include <linux/nfsd/xdr3.h>
+#include <linux/posix_acl.h>
+#include <linux/nfsacl.h>
+
+#define RETURN_STATUS(st)	{ resp->status = (st); return (st); }
+
+/*
+ * NULL call.
+ */
+static int
+nfsd3_proc_null(struct svc_rqst *rqstp, void *argp, void *resp)
+{
+	return nfs_ok;
+}
+
+/*
+ * Get the Access and/or Default ACL of a file.
+ */
+static int nfsd3_proc_getacl(struct svc_rqst * rqstp,
+		struct nfsd3_getaclargs *argp, struct nfsd3_getaclres *resp)
+{
+	svc_fh *fh;
+	struct posix_acl *acl;
+	int nfserr = 0;
+
+	fh = fh_copy(&resp->fh, &argp->fh);
+	if ((nfserr = fh_verify(rqstp, &resp->fh, 0, MAY_NOP)))
+		RETURN_STATUS(nfserr_inval);
+
+	if (argp->mask & ~(NFS_ACL|NFS_ACLCNT|NFS_DFACL|NFS_DFACLCNT))
+		RETURN_STATUS(nfserr_inval);
+	resp->mask = argp->mask;
+
+	if (resp->mask & (NFS_ACL|NFS_ACLCNT)) {
+		acl = nfsd_get_posix_acl(fh, ACL_TYPE_ACCESS);
+		if (IS_ERR(acl)) {
+			int err = PTR_ERR(acl);
+
+			if (err == -ENODATA || err == -EOPNOTSUPP)
+				acl = NULL;
+			else {
+				nfserr = nfserrno(err);
+				goto fail;
+			}
+		}
+		if (acl == NULL) {
+			/* Solaris returns the inode's minimum ACL. */
+
+			struct inode *inode = fh->fh_dentry->d_inode;
+			acl = posix_acl_from_mode(inode->i_mode, GFP_KERNEL);
+		}
+		resp->acl_access = acl;
+	}
+	if (resp->mask & (NFS_DFACL|NFS_DFACLCNT)) {
+		/* Check how Solaris handles requests for the Default ACL
+		   of a non-directory! */
+
+		acl = nfsd_get_posix_acl(fh, ACL_TYPE_DEFAULT);
+		if (IS_ERR(acl)) {
+			int err = PTR_ERR(acl);
+
+			if (err == -ENODATA || err == -EOPNOTSUPP)
+				acl = NULL;
+			else {
+				nfserr = nfserrno(err);
+				goto fail;
+			}
+		}
+		resp->acl_default = acl;
+	}
+
+	/* resp->acl_{access,default} are released in nfs3svc_release_getacl. */
+	RETURN_STATUS(0);
+
+fail:
+	posix_acl_release(resp->acl_access);
+	posix_acl_release(resp->acl_default);
+	RETURN_STATUS(nfserr);
+}
+
+/*
+ * Set the Access and/or Default ACL of a file.
+ */
+static int nfsd3_proc_setacl(struct svc_rqst * rqstp,
+		struct nfsd3_setaclargs *argp,
+		struct nfsd3_attrstat *resp)
+{
+	svc_fh *fh;
+	int nfserr = 0;
+
+	fh = fh_copy(&resp->fh, &argp->fh);
+	nfserr = fh_verify(rqstp, &resp->fh, 0, MAY_NOP);
+
+	if (!nfserr) {
+		nfserr = nfserrno( nfsd_set_posix_acl(
+			fh, ACL_TYPE_ACCESS, argp->acl_access) );
+	}
+	if (!nfserr) {
+		nfserr = nfserrno( nfsd_set_posix_acl(
+			fh, ACL_TYPE_DEFAULT, argp->acl_default) );
+	}
+
+	/* argp->acl_{access,default} may have been allocated in
+	   nfs3svc_decode_setaclargs. */
+	posix_acl_release(argp->acl_access);
+	posix_acl_release(argp->acl_default);
+	RETURN_STATUS(nfserr);
+}
+
+/*
+ * XDR decode functions
+ */
+static int nfs3svc_decode_getaclargs(struct svc_rqst *rqstp, u32 *p,
+		struct nfsd3_getaclargs *args)
+{
+	if (!(p = nfs3svc_decode_fh(p, &args->fh)))
+		return 0;
+	args->mask = ntohl(*p); p++;
+
+	return xdr_argsize_check(rqstp, p);
+}
+
+
+static int nfs3svc_decode_setaclargs(struct svc_rqst *rqstp, u32 *p,
+		struct nfsd3_setaclargs *args)
+{
+	struct kvec *head = rqstp->rq_arg.head;
+	unsigned int base;
+	int n;
+
+	if (!(p = nfs3svc_decode_fh(p, &args->fh)))
+		return 0;
+	args->mask = ntohl(*p++);
+	if (args->mask & ~(NFS_ACL|NFS_ACLCNT|NFS_DFACL|NFS_DFACLCNT) ||
+	    !xdr_argsize_check(rqstp, p))
+		return 0;
+
+	base = (char *)p - (char *)head->iov_base;
+	n = nfsacl_decode(&rqstp->rq_arg, base, NULL,
+			  (args->mask & NFS_ACL) ?
+			  &args->acl_access : NULL);
+	if (n > 0)
+		n = nfsacl_decode(&rqstp->rq_arg, base + n, NULL,
+				  (args->mask & NFS_DFACL) ?
+				  &args->acl_default : NULL);
+	return (n > 0);
+}
+
+/*
+ * XDR encode functions
+ */
+
+/* GETACL */
+static int nfs3svc_encode_getaclres(struct svc_rqst *rqstp, u32 *p,
+		struct nfsd3_getaclres *resp)
+{
+	struct dentry *dentry = resp->fh.fh_dentry;
+
+	p = nfs3svc_encode_post_op_attr(rqstp, p, &resp->fh);
+	if (resp->status == 0 && dentry && dentry->d_inode) {
+		struct inode *inode = dentry->d_inode;
+		int w = nfsacl_size(
+			(resp->mask & NFS_ACL)   ? resp->acl_access  : NULL,
+			(resp->mask & NFS_DFACL) ? resp->acl_default : NULL);
+		struct kvec *head = rqstp->rq_res.head;
+		unsigned int base;
+		int n;
+
+		*p++ = htonl(resp->mask);
+		if (!xdr_ressize_check(rqstp, p))
+			return 0;
+		base = (char *)p - (char *)head->iov_base;
+
+		rqstp->rq_res.page_len = w;
+		while (w > 0) {
+			if (!svc_take_res_page(rqstp))
+				return 0;
+			w -= PAGE_SIZE;
+		}
+
+		n = nfsacl_encode(&rqstp->rq_res, base, inode,
+				  resp->acl_access,
+				  resp->mask & NFS_ACL, 0);
+		if (n > 0)
+			n = nfsacl_encode(&rqstp->rq_res, base + n, inode,
+					  resp->acl_default,
+					  resp->mask & NFS_DFACL,
+					  NFS_ACL_DEFAULT);
+		if (n <= 0)
+			return 0;
+	} else
+		if (!xdr_ressize_check(rqstp, p))
+			return 0;
+
+	return 1;
+}
+
+/* SETACL */
+static int nfs3svc_encode_setaclres(struct svc_rqst *rqstp, u32 *p,
+		struct nfsd3_attrstat *resp)
+{
+	p = nfs3svc_encode_post_op_attr(rqstp, p, &resp->fh);
+
+	return xdr_ressize_check(rqstp, p);
+}
+
+/*
+ * XDR release functions
+ */
+static int nfs3svc_release_getacl(struct svc_rqst *rqstp, u32 *p,
+		struct nfsd3_getaclres *resp)
+{
+	fh_put(&resp->fh);
+	posix_acl_release(resp->acl_access);
+	posix_acl_release(resp->acl_default);
+	return 1;
+}
+
+#define nfs3svc_decode_voidargs		NULL
+#define nfs3svc_release_void		NULL
+#define nfsd3_setaclres			nfsd3_attrstat
+#define nfsd3_voidres			nfsd3_voidargs
+struct nfsd3_voidargs { int dummy; };
+
+#define PROC(name, argt, rest, relt, cache, respsize)	\
+ { (svc_procfunc) nfsd3_proc_##name,		\
+   (kxdrproc_t) nfs3svc_decode_##argt##args,	\
+   (kxdrproc_t) nfs3svc_encode_##rest##res,	\
+   (kxdrproc_t) nfs3svc_release_##relt,		\
+   sizeof(struct nfsd3_##argt##args),		\
+   sizeof(struct nfsd3_##rest##res),		\
+   0,						\
+   cache,					\
+   respsize,					\
+ }
+
+#define ST 1		/* status*/
+#define AT 21		/* attributes */
+#define pAT (1+AT)	/* post attributes - conditional */
+#define ACL (1+NFS_ACL_MAX_ENTRIES*3)  /* Access Control List */
+
+static struct svc_procedure		nfsd_acl_procedures3[] = {
+  PROC(null,	void,		void,		void,	  RC_NOCACHE, ST),
+  PROC(getacl,	getacl,		getacl,		getacl,	  RC_NOCACHE, ST+1+2*(1+ACL)),
+  PROC(setacl,	setacl,		setacl,		fhandle,  RC_NOCACHE, ST+pAT),
+};
+
+struct svc_version	nfsd_acl_version3 = {
+		.vs_vers	= 3,
+		.vs_nproc	= 3,
+		.vs_proc	= nfsd_acl_procedures3,
+		.vs_dispatch	= nfsd_dispatch,
+		.vs_xdrsize	= NFS3_SVC_XDRSIZE,
+};
+

fs/nfsd/nfs3xdr.c

···
 	return p + XDR_QUADLEN(size);
 }
 
+/* Helper function for NFSv3 ACL code */
+u32 *nfs3svc_decode_fh(u32 *p, struct svc_fh *fhp)
+{
+	return decode_fh(p, fhp);
+}
+
 static inline u32 *
 encode_fh(u32 *p, struct svc_fh *fhp)
 {
···
 	}
 	*p++ = xdr_zero;
 	return p;
+}
+
+/* Helper for NFSv3 ACLs */
+u32 *
+nfs3svc_encode_post_op_attr(struct svc_rqst *rqstp, u32 *p, struct svc_fh *fhp)
+{
+	return encode_post_op_attr(rqstp, p, fhp);
 }
 
 /*

fs/nfsd/nfssvc.c

···
 #include <linux/nfsd/stats.h>
 #include <linux/nfsd/cache.h>
 #include <linux/lockd/bind.h>
+#include <linux/nfsacl.h>
 
 #define NFSDDBG_FACILITY	NFSDDBG_SVC
 
···
 	return 1;
 }
 
+#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
+static struct svc_stat	nfsd_acl_svcstats;
+static struct svc_version *	nfsd_acl_version[] = {
+	[2] = &nfsd_acl_version2,
+	[3] = &nfsd_acl_version3,
+};
+
+#define NFSD_ACL_NRVERS		(sizeof(nfsd_acl_version)/sizeof(nfsd_acl_version[0]))
+static struct svc_program	nfsd_acl_program = {
+	.pg_prog		= NFS_ACL_PROGRAM,
+	.pg_nvers		= NFSD_ACL_NRVERS,
+	.pg_vers		= nfsd_acl_version,
+	.pg_name		= "nfsd",
+	.pg_stats		= &nfsd_acl_svcstats,
+};
+
+static struct svc_stat	nfsd_acl_svcstats = {
+	.program	= &nfsd_acl_program,
+};
+
+#define nfsd_acl_program_p	&nfsd_acl_program
+#else
+#define nfsd_acl_program_p	NULL
+#endif /* defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) */
+
 extern struct svc_version nfsd_version2, nfsd_version3, nfsd_version4;
 
 static struct svc_version *	nfsd_version[] = {
···
 
 #define NFSD_NRVERS		(sizeof(nfsd_version)/sizeof(nfsd_version[0]))
 struct svc_program		nfsd_program = {
+	.pg_next		= nfsd_acl_program_p,
 	.pg_prog		= NFS_PROGRAM,		/* program number */
 	.pg_nvers		= NFSD_NRVERS,		/* nr of entries in nfsd_version */
 	.pg_vers		= nfsd_version,		/* version table */

fs/nfsd/nfsxdr.c

···
 	return p + (NFS_FHSIZE >> 2);
 }
 
+/* Helper function for NFSv2 ACL code */
+u32 *nfs2svc_decode_fh(u32 *p, struct svc_fh *fhp)
+{
+	return decode_fh(p, fhp);
+}
+
 static inline u32 *
 encode_fh(u32 *p, struct svc_fh *fhp)
 {
···
 	return p;
 }
 
+/* Helper function for NFSv2 ACL code */
+u32 *nfs2svc_encode_fattr(struct svc_rqst *rqstp, u32 *p, struct svc_fh *fhp)
+{
+	return encode_fattr(rqstp, p, fhp);
+}
 
 /*
  * XDR decode functions

fs/nfsd/vfs.c

···
 #include <linux/nfsd/nfsfh.h>
 #include <linux/quotaops.h>
 #include <linux/dnotify.h>
-#ifdef CONFIG_NFSD_V4
+#include <linux/xattr_acl.h>
 #include <linux/posix_acl.h>
+#ifdef CONFIG_NFSD_V4
 #include <linux/posix_acl_xattr.h>
 #include <linux/xattr_acl.h>
 #include <linux/xattr.h>
···
 	nfsdstats.ra_size = cache_size;
 	return 0;
 }
+
+#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
+struct posix_acl *
+nfsd_get_posix_acl(struct svc_fh *fhp, int type)
+{
+	struct inode *inode = fhp->fh_dentry->d_inode;
+	char *name;
+	void *value = NULL;
+	ssize_t size;
+	struct posix_acl *acl;
+
+	if (!IS_POSIXACL(inode) || !inode->i_op || !inode->i_op->getxattr)
+		return ERR_PTR(-EOPNOTSUPP);
+	switch(type) {
+		case ACL_TYPE_ACCESS:
+			name = XATTR_NAME_ACL_ACCESS;
+			break;
+		case ACL_TYPE_DEFAULT:
+			name = XATTR_NAME_ACL_DEFAULT;
+			break;
+		default:
+			return ERR_PTR(-EOPNOTSUPP);
+	}
+
+	size = inode->i_op->getxattr(fhp->fh_dentry, name, NULL, 0);
+
+	if (size < 0) {
+		acl = ERR_PTR(size);
+		goto getout;
+	} else if (size > 0) {
+		value = kmalloc(size, GFP_KERNEL);
+		if (!value) {
+			acl = ERR_PTR(-ENOMEM);
+			goto getout;
+		}
+		size = inode->i_op->getxattr(fhp->fh_dentry, name, value, size);
+		if (size < 0) {
+			acl = ERR_PTR(size);
+			goto getout;
+		}
+	}
+	acl = posix_acl_from_xattr(value, size);
+
+getout:
+	kfree(value);
+	return acl;
+}
+
+int
+nfsd_set_posix_acl(struct svc_fh *fhp, int type, struct posix_acl *acl)
+{
+	struct inode *inode = fhp->fh_dentry->d_inode;
+	char *name;
+	void *value = NULL;
+	size_t size;
+	int error;
+
+	if (!IS_POSIXACL(inode) || !inode->i_op ||
+	    !inode->i_op->setxattr || !inode->i_op->removexattr)
+		return -EOPNOTSUPP;
+	switch(type) {
+		case ACL_TYPE_ACCESS:
+			name = XATTR_NAME_ACL_ACCESS;
+			break;
+		case ACL_TYPE_DEFAULT:
+			name = XATTR_NAME_ACL_DEFAULT;
+			break;
+		default:
+			return -EOPNOTSUPP;
+	}
+
+	if (acl && acl->a_count) {
+		size = xattr_acl_size(acl->a_count);
+		value = kmalloc(size, GFP_KERNEL);
+		if (!value)
+			return -ENOMEM;
+		size = posix_acl_to_xattr(acl, value, size);
+		if (size < 0) {
+			error = size;
+			goto getout;
+		}
+	} else
+		size = 0;
+
+	if (!fhp->fh_locked)
+		fh_lock(fhp);  /* unlocking is done automatically */
+	if (size)
+		error = inode->i_op->setxattr(fhp->fh_dentry, name,
+					      value, size, 0);
+	else {
+		if (!S_ISDIR(inode->i_mode) && type == ACL_TYPE_DEFAULT)
+			error = 0;
+		else {
+			error = inode->i_op->removexattr(fhp->fh_dentry, name);
+			if (error == -ENODATA)
+				error = 0;
+		}
+	}
+
+getout:
+	kfree(value);
+	return error;
+}
+#endif  /* defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) */

include/linux/nfsacl.h

···
+/*
+ * File: linux/nfsacl.h
+ *
+ * (C) 2003 Andreas Gruenbacher <[e-mail]>
+ */
+#ifndef __LINUX_NFSACL_H
+#define __LINUX_NFSACL_H
+
+#define NFS_ACL_PROGRAM	100227
+
+#define ACLPROC2_GETACL		1
+#define ACLPROC2_SETACL		2
+#define ACLPROC2_GETATTR	3
+#define ACLPROC2_ACCESS		4
+
+#define ACLPROC3_GETACL		1
+#define ACLPROC3_SETACL		2
+
+
+/* Flags for the getacl/setacl mode */
+#define NFS_ACL			0x0001
+#define NFS_ACLCNT		0x0002
+#define NFS_DFACL		0x0004
+#define NFS_DFACLCNT		0x0008
+
+/* Flag for Default ACL entries */
+#define NFS_ACL_DEFAULT		0x1000
+
+#ifdef __KERNEL__
+
+#include <linux/posix_acl.h>
+
+/* Maximum number of ACL entries over NFS */
+#define NFS_ACL_MAX_ENTRIES	1024
+
+#define NFSACL_MAXWORDS		(2*(2+3*NFS_ACL_MAX_ENTRIES))
+#define NFSACL_MAXPAGES		((2*(8+12*NFS_ACL_MAX_ENTRIES) + PAGE_SIZE-1) \
+				 >> PAGE_SHIFT)
+
+static inline unsigned int
+nfsacl_size(struct posix_acl *acl_access, struct posix_acl *acl_default)
+{
+	unsigned int w = 16;
+	w += max(acl_access ? (int)acl_access->a_count : 3, 4) * 12;
+	if (acl_default)
+		w += max((int)acl_default->a_count, 4) * 12;
+	return w;
+}
+
+extern unsigned int
+nfsacl_encode(struct xdr_buf *buf, unsigned int base, struct inode *inode,
+	      struct posix_acl *acl, int encode_entries, int typeflag);
+extern unsigned int
+nfsacl_decode(struct xdr_buf *buf, unsigned int base, unsigned int *aclcnt,
+	      struct posix_acl **pacl);
+
+#endif /* __KERNEL__ */
+#endif  /* __LINUX_NFSACL_H */

include/linux/nfsd/nfsd.h

···
 #include <linux/unistd.h>
 #include <linux/dirent.h>
 #include <linux/fs.h>
+#include <linux/posix_acl.h>
 #include <linux/mount.h>
 
 #include <linux/nfsd/debug.h>
···
 
 int		nfsd_notify_change(struct inode *, struct iattr *);
 int		nfsd_permission(struct svc_export *, struct dentry *, int);
+
+#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL)
+#ifdef CONFIG_NFSD_V2_ACL
+extern struct svc_version nfsd_acl_version2;
+#else
+#define nfsd_acl_version2 NULL
+#endif
+#ifdef CONFIG_NFSD_V3_ACL
+extern struct svc_version nfsd_acl_version3;
+#else
+#define nfsd_acl_version3 NULL
+#endif
+struct posix_acl *nfsd_get_posix_acl(struct svc_fh *, int);
+int nfsd_set_posix_acl(struct svc_fh *, int, struct posix_acl *);
+#endif
 
 
 /* 

include/linux/nfsd/xdr.h

···
 
 int nfssvc_release_fhandle(struct svc_rqst *, u32 *, struct nfsd_fhandle *);
 
+/* Helper functions for NFSv2 ACL code */
+u32 *nfs2svc_encode_fattr(struct svc_rqst *rqstp, u32 *p, struct svc_fh *fhp);
+u32 *nfs2svc_decode_fh(u32 *p, struct svc_fh *fhp);
+
 #endif /* LINUX_NFSD_H */

include/linux/nfsd/xdr3.h

···
 	__u32			count;
 };
 
+struct nfsd3_getaclargs {
+	struct svc_fh		fh;
+	int			mask;
+};
+
+struct posix_acl;
+struct nfsd3_setaclargs {
+	struct svc_fh		fh;
+	int			mask;
+	struct posix_acl	*acl_access;
+	struct posix_acl	*acl_default;
+};
+
 struct nfsd3_attrstat {
 	__u32			status;
 	struct svc_fh		fh;
···
 	struct svc_fh		fh;
 };
 
+struct nfsd3_getaclres {
+	__u32			status;
+	struct svc_fh		fh;
+	int			mask;
+	struct posix_acl	*acl_access;
+	struct posix_acl	*acl_default;
+};
+
 /* dummy type for release */
 struct nfsd3_fhandle_pair {
 	__u32			dummy;
···
 	struct nfsd3_fsinfores		fsinfores;
 	struct nfsd3_pathconfres	pathconfres;
 	struct nfsd3_commitres		commitres;
+	struct nfsd3_getaclres		getaclres;
 };
 
 #define NFS3_SVC_XDRSIZE		sizeof(union nfsd3_xdrstore)
···
 int nfs3svc_encode_entry_plus(struct readdir_cd *, const char *name,
 				int namlen, loff_t offset, ino_t ino,
 				unsigned int);
+/* Helper functions for NFSv3 ACL code */
+u32 *nfs3svc_encode_post_op_attr(struct svc_rqst *rqstp, u32 *p,
+				struct svc_fh *fhp);
+u32 *nfs3svc_decode_fh(u32 *p, struct svc_fh *fhp);
 
 
 #endif /* _LINUX_NFSD_XDR3_H */

include/linux/sunrpc/svc.h

···
 	return vec->iov_len <= PAGE_SIZE;
 }
 
+static inline struct page *
+svc_take_res_page(struct svc_rqst *rqstp)
+{
+	if (rqstp->rq_arghi <= rqstp->rq_argused)
+		return NULL;
+	rqstp->rq_arghi--;
+	rqstp->rq_respages[rqstp->rq_resused] =
+		rqstp->rq_argpages[rqstp->rq_arghi];
+	return rqstp->rq_respages[rqstp->rq_resused++];
+}
+
 static inline int svc_take_page(struct svc_rqst *rqstp)
 {
 	if (rqstp->rq_arghi <= rqstp->rq_argused)