[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 <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>

1 files changed, 267 insertions, 0 deletions

diff --git a/fs/nfsd/nfs3acl.c b/fs/nfsd/nfs3acl.c
new file mode 100644
index 000000000000..64ba40572fea
--- /dev/null
+++ b/fs/nfsd/nfs3acl.c
@@ -0,0 +1,267 @@
+/*
+ * linux/fs/nfsd/nfs3acl.c
+ *
+ * Process version 3 NFSACL requests.
+ *
+ * Copyright (C) 2002-2003 Andreas Gruenbacher <agruen@suse.de>
+ */
+
+#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,
+};
+