xref: /kernel/linux/linux-5.10/fs/nfsd/nfs3acl.c (revision 8c2ecf20)
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Process version 3 NFSACL requests.
4 *
5 * Copyright (C) 2002-2003 Andreas Gruenbacher <agruen@suse.de>
6 */
7
8#include "nfsd.h"
9/* FIXME: nfsacl.h is a broken header */
10#include <linux/nfsacl.h>
11#include <linux/gfp.h>
12#include "cache.h"
13#include "xdr3.h"
14#include "vfs.h"
15
16/*
17 * NULL call.
18 */
19static __be32
20nfsd3_proc_null(struct svc_rqst *rqstp)
21{
22	return rpc_success;
23}
24
25/*
26 * Get the Access and/or Default ACL of a file.
27 */
28static __be32 nfsd3_proc_getacl(struct svc_rqst *rqstp)
29{
30	struct nfsd3_getaclargs *argp = rqstp->rq_argp;
31	struct nfsd3_getaclres *resp = rqstp->rq_resp;
32	struct posix_acl *acl;
33	struct inode *inode;
34	svc_fh *fh;
35
36	fh = fh_copy(&resp->fh, &argp->fh);
37	resp->status = fh_verify(rqstp, &resp->fh, 0, NFSD_MAY_NOP);
38	if (resp->status != nfs_ok)
39		goto out;
40
41	inode = d_inode(fh->fh_dentry);
42
43	if (argp->mask & ~NFS_ACL_MASK) {
44		resp->status = nfserr_inval;
45		goto out;
46	}
47	resp->mask = argp->mask;
48
49	if (resp->mask & (NFS_ACL|NFS_ACLCNT)) {
50		acl = get_acl(inode, ACL_TYPE_ACCESS);
51		if (acl == NULL) {
52			/* Solaris returns the inode's minimum ACL. */
53			acl = posix_acl_from_mode(inode->i_mode, GFP_KERNEL);
54		}
55		if (IS_ERR(acl)) {
56			resp->status = nfserrno(PTR_ERR(acl));
57			goto fail;
58		}
59		resp->acl_access = acl;
60	}
61	if (resp->mask & (NFS_DFACL|NFS_DFACLCNT)) {
62		/* Check how Solaris handles requests for the Default ACL
63		   of a non-directory! */
64		acl = get_acl(inode, ACL_TYPE_DEFAULT);
65		if (IS_ERR(acl)) {
66			resp->status = nfserrno(PTR_ERR(acl));
67			goto fail;
68		}
69		resp->acl_default = acl;
70	}
71
72	/* resp->acl_{access,default} are released in nfs3svc_release_getacl. */
73out:
74	return rpc_success;
75
76fail:
77	posix_acl_release(resp->acl_access);
78	posix_acl_release(resp->acl_default);
79	goto out;
80}
81
82/*
83 * Set the Access and/or Default ACL of a file.
84 */
85static __be32 nfsd3_proc_setacl(struct svc_rqst *rqstp)
86{
87	struct nfsd3_setaclargs *argp = rqstp->rq_argp;
88	struct nfsd3_attrstat *resp = rqstp->rq_resp;
89	struct inode *inode;
90	svc_fh *fh;
91	int error;
92
93	fh = fh_copy(&resp->fh, &argp->fh);
94	resp->status = fh_verify(rqstp, &resp->fh, 0, NFSD_MAY_SATTR);
95	if (resp->status != nfs_ok)
96		goto out;
97
98	inode = d_inode(fh->fh_dentry);
99
100	error = fh_want_write(fh);
101	if (error)
102		goto out_errno;
103
104	fh_lock(fh);
105
106	error = set_posix_acl(inode, ACL_TYPE_ACCESS, argp->acl_access);
107	if (error)
108		goto out_drop_lock;
109	error = set_posix_acl(inode, ACL_TYPE_DEFAULT, argp->acl_default);
110
111out_drop_lock:
112	fh_unlock(fh);
113	fh_drop_write(fh);
114out_errno:
115	resp->status = nfserrno(error);
116out:
117	/* argp->acl_{access,default} may have been allocated in
118	   nfs3svc_decode_setaclargs. */
119	posix_acl_release(argp->acl_access);
120	posix_acl_release(argp->acl_default);
121	return rpc_success;
122}
123
124/*
125 * XDR decode functions
126 */
127static int nfs3svc_decode_getaclargs(struct svc_rqst *rqstp, __be32 *p)
128{
129	struct nfsd3_getaclargs *args = rqstp->rq_argp;
130
131	p = nfs3svc_decode_fh(p, &args->fh);
132	if (!p)
133		return 0;
134	args->mask = ntohl(*p); p++;
135
136	return xdr_argsize_check(rqstp, p);
137}
138
139
140static int nfs3svc_decode_setaclargs(struct svc_rqst *rqstp, __be32 *p)
141{
142	struct nfsd3_setaclargs *args = rqstp->rq_argp;
143	struct kvec *head = rqstp->rq_arg.head;
144	unsigned int base;
145	int n;
146
147	p = nfs3svc_decode_fh(p, &args->fh);
148	if (!p)
149		return 0;
150	args->mask = ntohl(*p++);
151	if (args->mask & ~NFS_ACL_MASK ||
152	    !xdr_argsize_check(rqstp, p))
153		return 0;
154
155	base = (char *)p - (char *)head->iov_base;
156	n = nfsacl_decode(&rqstp->rq_arg, base, NULL,
157			  (args->mask & NFS_ACL) ?
158			  &args->acl_access : NULL);
159	if (n > 0)
160		n = nfsacl_decode(&rqstp->rq_arg, base + n, NULL,
161				  (args->mask & NFS_DFACL) ?
162				  &args->acl_default : NULL);
163	return (n > 0);
164}
165
166/*
167 * XDR encode functions
168 */
169
170/* GETACL */
171static int nfs3svc_encode_getaclres(struct svc_rqst *rqstp, __be32 *p)
172{
173	struct nfsd3_getaclres *resp = rqstp->rq_resp;
174	struct dentry *dentry = resp->fh.fh_dentry;
175
176	*p++ = resp->status;
177	p = nfs3svc_encode_post_op_attr(rqstp, p, &resp->fh);
178	if (resp->status == 0 && dentry && d_really_is_positive(dentry)) {
179		struct inode *inode = d_inode(dentry);
180		struct kvec *head = rqstp->rq_res.head;
181		unsigned int base;
182		int n;
183		int w;
184
185		*p++ = htonl(resp->mask);
186		if (!xdr_ressize_check(rqstp, p))
187			return 0;
188		base = (char *)p - (char *)head->iov_base;
189
190		rqstp->rq_res.page_len = w = nfsacl_size(
191			(resp->mask & NFS_ACL)   ? resp->acl_access  : NULL,
192			(resp->mask & NFS_DFACL) ? resp->acl_default : NULL);
193		while (w > 0) {
194			if (!*(rqstp->rq_next_page++))
195				return 0;
196			w -= PAGE_SIZE;
197		}
198
199		n = nfsacl_encode(&rqstp->rq_res, base, inode,
200				  resp->acl_access,
201				  resp->mask & NFS_ACL, 0);
202		if (n > 0)
203			n = nfsacl_encode(&rqstp->rq_res, base + n, inode,
204					  resp->acl_default,
205					  resp->mask & NFS_DFACL,
206					  NFS_ACL_DEFAULT);
207		if (n <= 0)
208			return 0;
209	} else
210		if (!xdr_ressize_check(rqstp, p))
211			return 0;
212
213	return 1;
214}
215
216/* SETACL */
217static int nfs3svc_encode_setaclres(struct svc_rqst *rqstp, __be32 *p)
218{
219	struct nfsd3_attrstat *resp = rqstp->rq_resp;
220
221	*p++ = resp->status;
222	p = nfs3svc_encode_post_op_attr(rqstp, p, &resp->fh);
223	return xdr_ressize_check(rqstp, p);
224}
225
226/*
227 * XDR release functions
228 */
229static void nfs3svc_release_getacl(struct svc_rqst *rqstp)
230{
231	struct nfsd3_getaclres *resp = rqstp->rq_resp;
232
233	fh_put(&resp->fh);
234	posix_acl_release(resp->acl_access);
235	posix_acl_release(resp->acl_default);
236}
237
238struct nfsd3_voidargs { int dummy; };
239
240#define ST 1		/* status*/
241#define AT 21		/* attributes */
242#define pAT (1+AT)	/* post attributes - conditional */
243#define ACL (1+NFS_ACL_MAX_ENTRIES*3)  /* Access Control List */
244
245static const struct svc_procedure nfsd_acl_procedures3[3] = {
246	[ACLPROC3_NULL] = {
247		.pc_func = nfsd3_proc_null,
248		.pc_decode = nfs3svc_decode_voidarg,
249		.pc_encode = nfs3svc_encode_voidres,
250		.pc_argsize = sizeof(struct nfsd3_voidargs),
251		.pc_ressize = sizeof(struct nfsd3_voidargs),
252		.pc_cachetype = RC_NOCACHE,
253		.pc_xdrressize = ST,
254	},
255	[ACLPROC3_GETACL] = {
256		.pc_func = nfsd3_proc_getacl,
257		.pc_decode = nfs3svc_decode_getaclargs,
258		.pc_encode = nfs3svc_encode_getaclres,
259		.pc_release = nfs3svc_release_getacl,
260		.pc_argsize = sizeof(struct nfsd3_getaclargs),
261		.pc_ressize = sizeof(struct nfsd3_getaclres),
262		.pc_cachetype = RC_NOCACHE,
263		.pc_xdrressize = ST+1+2*(1+ACL),
264	},
265	[ACLPROC3_SETACL] = {
266		.pc_func = nfsd3_proc_setacl,
267		.pc_decode = nfs3svc_decode_setaclargs,
268		.pc_encode = nfs3svc_encode_setaclres,
269		.pc_release = nfs3svc_release_fhandle,
270		.pc_argsize = sizeof(struct nfsd3_setaclargs),
271		.pc_ressize = sizeof(struct nfsd3_attrstat),
272		.pc_cachetype = RC_NOCACHE,
273		.pc_xdrressize = ST+pAT,
274	},
275};
276
277static unsigned int nfsd_acl_count3[ARRAY_SIZE(nfsd_acl_procedures3)];
278const struct svc_version nfsd_acl_version3 = {
279	.vs_vers	= 3,
280	.vs_nproc	= 3,
281	.vs_proc	= nfsd_acl_procedures3,
282	.vs_count	= nfsd_acl_count3,
283	.vs_dispatch	= nfsd_dispatch,
284	.vs_xdrsize	= NFS3_SVC_XDRSIZE,
285};
286
287