xref: /openbmc/linux/fs/nfsd/nfs3acl.c (revision 84b102f5)
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  */
19 static __be32
20 nfsd3_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  */
28 static __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. */
73 out:
74 	return rpc_success;
75 
76 fail:
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  */
85 static __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 
111 out_drop_lock:
112 	fh_unlock(fh);
113 	fh_drop_write(fh);
114 out_errno:
115 	resp->status = nfserrno(error);
116 out:
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  */
127 static 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 
140 static 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 */
171 static 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 */
217 static 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  */
229 static 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 
238 struct 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 
245 static const struct svc_procedure nfsd_acl_procedures3[3] = {
246 	[ACLPROC3_NULL] = {
247 		.pc_func = nfsd3_proc_null,
248 		.pc_decode = nfssvc_decode_voidarg,
249 		.pc_encode = nfssvc_encode_voidres,
250 		.pc_argsize = sizeof(struct nfsd_voidargs),
251 		.pc_ressize = sizeof(struct nfsd_voidres),
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 
277 static unsigned int nfsd_acl_count3[ARRAY_SIZE(nfsd_acl_procedures3)];
278 const 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