xref: /linux/fs/nfsd/nfs2acl.c (revision 74ce1896c6c65b2f8cccbf59162d542988835835)
1 /*
2  * Process version 2 NFSACL requests.
3  *
4  * Copyright (C) 2002-2003 Andreas Gruenbacher <agruen@suse.de>
5  */
6 
7 #include "nfsd.h"
8 /* FIXME: nfsacl.h is a broken header */
9 #include <linux/nfsacl.h>
10 #include <linux/gfp.h>
11 #include "cache.h"
12 #include "xdr3.h"
13 #include "vfs.h"
14 
15 #define NFSDDBG_FACILITY		NFSDDBG_PROC
16 #define RETURN_STATUS(st)	{ resp->status = (st); return (st); }
17 
18 /*
19  * NULL call.
20  */
21 static __be32
22 nfsacld_proc_null(struct svc_rqst *rqstp)
23 {
24 	return nfs_ok;
25 }
26 
27 /*
28  * Get the Access and/or Default ACL of a file.
29  */
30 static __be32 nfsacld_proc_getacl(struct svc_rqst *rqstp)
31 {
32 	struct nfsd3_getaclargs *argp = rqstp->rq_argp;
33 	struct nfsd3_getaclres *resp = rqstp->rq_resp;
34 	struct posix_acl *acl;
35 	struct inode *inode;
36 	svc_fh *fh;
37 	__be32 nfserr = 0;
38 
39 	dprintk("nfsd: GETACL(2acl)   %s\n", SVCFH_fmt(&argp->fh));
40 
41 	fh = fh_copy(&resp->fh, &argp->fh);
42 	nfserr = fh_verify(rqstp, &resp->fh, 0, NFSD_MAY_NOP);
43 	if (nfserr)
44 		RETURN_STATUS(nfserr);
45 
46 	inode = d_inode(fh->fh_dentry);
47 
48 	if (argp->mask & ~NFS_ACL_MASK)
49 		RETURN_STATUS(nfserr_inval);
50 	resp->mask = argp->mask;
51 
52 	nfserr = fh_getattr(fh, &resp->stat);
53 	if (nfserr)
54 		RETURN_STATUS(nfserr);
55 
56 	if (resp->mask & (NFS_ACL|NFS_ACLCNT)) {
57 		acl = get_acl(inode, ACL_TYPE_ACCESS);
58 		if (acl == NULL) {
59 			/* Solaris returns the inode's minimum ACL. */
60 			acl = posix_acl_from_mode(inode->i_mode, GFP_KERNEL);
61 		}
62 		if (IS_ERR(acl)) {
63 			nfserr = nfserrno(PTR_ERR(acl));
64 			goto fail;
65 		}
66 		resp->acl_access = acl;
67 	}
68 	if (resp->mask & (NFS_DFACL|NFS_DFACLCNT)) {
69 		/* Check how Solaris handles requests for the Default ACL
70 		   of a non-directory! */
71 		acl = get_acl(inode, ACL_TYPE_DEFAULT);
72 		if (IS_ERR(acl)) {
73 			nfserr = nfserrno(PTR_ERR(acl));
74 			goto fail;
75 		}
76 		resp->acl_default = acl;
77 	}
78 
79 	/* resp->acl_{access,default} are released in nfssvc_release_getacl. */
80 	RETURN_STATUS(0);
81 
82 fail:
83 	posix_acl_release(resp->acl_access);
84 	posix_acl_release(resp->acl_default);
85 	RETURN_STATUS(nfserr);
86 }
87 
88 /*
89  * Set the Access and/or Default ACL of a file.
90  */
91 static __be32 nfsacld_proc_setacl(struct svc_rqst *rqstp)
92 {
93 	struct nfsd3_setaclargs *argp = rqstp->rq_argp;
94 	struct nfsd_attrstat *resp = rqstp->rq_resp;
95 	struct inode *inode;
96 	svc_fh *fh;
97 	__be32 nfserr = 0;
98 	int error;
99 
100 	dprintk("nfsd: SETACL(2acl)   %s\n", SVCFH_fmt(&argp->fh));
101 
102 	fh = fh_copy(&resp->fh, &argp->fh);
103 	nfserr = fh_verify(rqstp, &resp->fh, 0, NFSD_MAY_SATTR);
104 	if (nfserr)
105 		goto out;
106 
107 	inode = d_inode(fh->fh_dentry);
108 
109 	error = fh_want_write(fh);
110 	if (error)
111 		goto out_errno;
112 
113 	fh_lock(fh);
114 
115 	error = set_posix_acl(inode, ACL_TYPE_ACCESS, argp->acl_access);
116 	if (error)
117 		goto out_drop_lock;
118 	error = set_posix_acl(inode, ACL_TYPE_DEFAULT, argp->acl_default);
119 	if (error)
120 		goto out_drop_lock;
121 
122 	fh_unlock(fh);
123 
124 	fh_drop_write(fh);
125 
126 	nfserr = fh_getattr(fh, &resp->stat);
127 
128 out:
129 	/* argp->acl_{access,default} may have been allocated in
130 	   nfssvc_decode_setaclargs. */
131 	posix_acl_release(argp->acl_access);
132 	posix_acl_release(argp->acl_default);
133 	return nfserr;
134 out_drop_lock:
135 	fh_unlock(fh);
136 	fh_drop_write(fh);
137 out_errno:
138 	nfserr = nfserrno(error);
139 	goto out;
140 }
141 
142 /*
143  * Check file attributes
144  */
145 static __be32 nfsacld_proc_getattr(struct svc_rqst *rqstp)
146 {
147 	struct nfsd_fhandle *argp = rqstp->rq_argp;
148 	struct nfsd_attrstat *resp = rqstp->rq_resp;
149 	__be32 nfserr;
150 	dprintk("nfsd: GETATTR  %s\n", SVCFH_fmt(&argp->fh));
151 
152 	fh_copy(&resp->fh, &argp->fh);
153 	nfserr = fh_verify(rqstp, &resp->fh, 0, NFSD_MAY_NOP);
154 	if (nfserr)
155 		return nfserr;
156 	nfserr = fh_getattr(&resp->fh, &resp->stat);
157 	return nfserr;
158 }
159 
160 /*
161  * Check file access
162  */
163 static __be32 nfsacld_proc_access(struct svc_rqst *rqstp)
164 {
165 	struct nfsd3_accessargs *argp = rqstp->rq_argp;
166 	struct nfsd3_accessres *resp = rqstp->rq_resp;
167 	__be32 nfserr;
168 
169 	dprintk("nfsd: ACCESS(2acl)   %s 0x%x\n",
170 			SVCFH_fmt(&argp->fh),
171 			argp->access);
172 
173 	fh_copy(&resp->fh, &argp->fh);
174 	resp->access = argp->access;
175 	nfserr = nfsd_access(rqstp, &resp->fh, &resp->access, NULL);
176 	if (nfserr)
177 		return nfserr;
178 	nfserr = fh_getattr(&resp->fh, &resp->stat);
179 	return nfserr;
180 }
181 
182 /*
183  * XDR decode functions
184  */
185 static int nfsaclsvc_decode_getaclargs(struct svc_rqst *rqstp, __be32 *p)
186 {
187 	struct nfsd3_getaclargs *argp = rqstp->rq_argp;
188 
189 	p = nfs2svc_decode_fh(p, &argp->fh);
190 	if (!p)
191 		return 0;
192 	argp->mask = ntohl(*p); p++;
193 
194 	return xdr_argsize_check(rqstp, p);
195 }
196 
197 
198 static int nfsaclsvc_decode_setaclargs(struct svc_rqst *rqstp, __be32 *p)
199 {
200 	struct nfsd3_setaclargs *argp = rqstp->rq_argp;
201 	struct kvec *head = rqstp->rq_arg.head;
202 	unsigned int base;
203 	int n;
204 
205 	p = nfs2svc_decode_fh(p, &argp->fh);
206 	if (!p)
207 		return 0;
208 	argp->mask = ntohl(*p++);
209 	if (argp->mask & ~NFS_ACL_MASK ||
210 	    !xdr_argsize_check(rqstp, p))
211 		return 0;
212 
213 	base = (char *)p - (char *)head->iov_base;
214 	n = nfsacl_decode(&rqstp->rq_arg, base, NULL,
215 			  (argp->mask & NFS_ACL) ?
216 			  &argp->acl_access : NULL);
217 	if (n > 0)
218 		n = nfsacl_decode(&rqstp->rq_arg, base + n, NULL,
219 				  (argp->mask & NFS_DFACL) ?
220 				  &argp->acl_default : NULL);
221 	return (n > 0);
222 }
223 
224 static int nfsaclsvc_decode_fhandleargs(struct svc_rqst *rqstp, __be32 *p)
225 {
226 	struct nfsd_fhandle *argp = rqstp->rq_argp;
227 
228 	p = nfs2svc_decode_fh(p, &argp->fh);
229 	if (!p)
230 		return 0;
231 	return xdr_argsize_check(rqstp, p);
232 }
233 
234 static int nfsaclsvc_decode_accessargs(struct svc_rqst *rqstp, __be32 *p)
235 {
236 	struct nfsd3_accessargs *argp = rqstp->rq_argp;
237 
238 	p = nfs2svc_decode_fh(p, &argp->fh);
239 	if (!p)
240 		return 0;
241 	argp->access = ntohl(*p++);
242 
243 	return xdr_argsize_check(rqstp, p);
244 }
245 
246 /*
247  * XDR encode functions
248  */
249 
250 /*
251  * There must be an encoding function for void results so svc_process
252  * will work properly.
253  */
254 static int nfsaclsvc_encode_voidres(struct svc_rqst *rqstp, __be32 *p)
255 {
256 	return xdr_ressize_check(rqstp, p);
257 }
258 
259 /* GETACL */
260 static int nfsaclsvc_encode_getaclres(struct svc_rqst *rqstp, __be32 *p)
261 {
262 	struct nfsd3_getaclres *resp = rqstp->rq_resp;
263 	struct dentry *dentry = resp->fh.fh_dentry;
264 	struct inode *inode;
265 	struct kvec *head = rqstp->rq_res.head;
266 	unsigned int base;
267 	int n;
268 	int w;
269 
270 	/*
271 	 * Since this is version 2, the check for nfserr in
272 	 * nfsd_dispatch actually ensures the following cannot happen.
273 	 * However, it seems fragile to depend on that.
274 	 */
275 	if (dentry == NULL || d_really_is_negative(dentry))
276 		return 0;
277 	inode = d_inode(dentry);
278 
279 	p = nfs2svc_encode_fattr(rqstp, p, &resp->fh, &resp->stat);
280 	*p++ = htonl(resp->mask);
281 	if (!xdr_ressize_check(rqstp, p))
282 		return 0;
283 	base = (char *)p - (char *)head->iov_base;
284 
285 	rqstp->rq_res.page_len = w = nfsacl_size(
286 		(resp->mask & NFS_ACL)   ? resp->acl_access  : NULL,
287 		(resp->mask & NFS_DFACL) ? resp->acl_default : NULL);
288 	while (w > 0) {
289 		if (!*(rqstp->rq_next_page++))
290 			return 0;
291 		w -= PAGE_SIZE;
292 	}
293 
294 	n = nfsacl_encode(&rqstp->rq_res, base, inode,
295 			  resp->acl_access,
296 			  resp->mask & NFS_ACL, 0);
297 	if (n > 0)
298 		n = nfsacl_encode(&rqstp->rq_res, base + n, inode,
299 				  resp->acl_default,
300 				  resp->mask & NFS_DFACL,
301 				  NFS_ACL_DEFAULT);
302 	return (n > 0);
303 }
304 
305 static int nfsaclsvc_encode_attrstatres(struct svc_rqst *rqstp, __be32 *p)
306 {
307 	struct nfsd_attrstat *resp = rqstp->rq_resp;
308 
309 	p = nfs2svc_encode_fattr(rqstp, p, &resp->fh, &resp->stat);
310 	return xdr_ressize_check(rqstp, p);
311 }
312 
313 /* ACCESS */
314 static int nfsaclsvc_encode_accessres(struct svc_rqst *rqstp, __be32 *p)
315 {
316 	struct nfsd3_accessres *resp = rqstp->rq_resp;
317 
318 	p = nfs2svc_encode_fattr(rqstp, p, &resp->fh, &resp->stat);
319 	*p++ = htonl(resp->access);
320 	return xdr_ressize_check(rqstp, p);
321 }
322 
323 /*
324  * XDR release functions
325  */
326 static void nfsaclsvc_release_getacl(struct svc_rqst *rqstp)
327 {
328 	struct nfsd3_getaclres *resp = rqstp->rq_resp;
329 
330 	fh_put(&resp->fh);
331 	posix_acl_release(resp->acl_access);
332 	posix_acl_release(resp->acl_default);
333 }
334 
335 static void nfsaclsvc_release_attrstat(struct svc_rqst *rqstp)
336 {
337 	struct nfsd_attrstat *resp = rqstp->rq_resp;
338 
339 	fh_put(&resp->fh);
340 }
341 
342 static void nfsaclsvc_release_access(struct svc_rqst *rqstp)
343 {
344 	struct nfsd3_accessres *resp = rqstp->rq_resp;
345 
346 	fh_put(&resp->fh);
347 }
348 
349 #define nfsaclsvc_decode_voidargs	NULL
350 #define nfsaclsvc_release_void		NULL
351 #define nfsd3_fhandleargs	nfsd_fhandle
352 #define nfsd3_attrstatres	nfsd_attrstat
353 #define nfsd3_voidres		nfsd3_voidargs
354 struct nfsd3_voidargs { int dummy; };
355 
356 #define PROC(name, argt, rest, relt, cache, respsize)			\
357 {									\
358 	.pc_func	= nfsacld_proc_##name,				\
359 	.pc_decode	= nfsaclsvc_decode_##argt##args,		\
360 	.pc_encode	= nfsaclsvc_encode_##rest##res,			\
361 	.pc_release	= nfsaclsvc_release_##relt,	\
362 	.pc_argsize	= sizeof(struct nfsd3_##argt##args),		\
363 	.pc_ressize	= sizeof(struct nfsd3_##rest##res),		\
364 	.pc_cachetype	= cache,					\
365 	.pc_xdrressize	= respsize,					\
366 }
367 
368 #define ST 1		/* status*/
369 #define AT 21		/* attributes */
370 #define pAT (1+AT)	/* post attributes - conditional */
371 #define ACL (1+NFS_ACL_MAX_ENTRIES*3)  /* Access Control List */
372 
373 static const struct svc_procedure nfsd_acl_procedures2[] = {
374   PROC(null,	void,		void,		void,	  RC_NOCACHE, ST),
375   PROC(getacl,	getacl,		getacl,		getacl,	  RC_NOCACHE, ST+1+2*(1+ACL)),
376   PROC(setacl,	setacl,		attrstat,	attrstat, RC_NOCACHE, ST+AT),
377   PROC(getattr, fhandle,	attrstat,	attrstat, RC_NOCACHE, ST+AT),
378   PROC(access,	access,		access,		access,   RC_NOCACHE, ST+AT+1),
379 };
380 
381 static unsigned int nfsd_acl_count2[ARRAY_SIZE(nfsd_acl_procedures2)];
382 const struct svc_version nfsd_acl_version2 = {
383 	.vs_vers	= 2,
384 	.vs_nproc	= 5,
385 	.vs_proc	= nfsd_acl_procedures2,
386 	.vs_count	= nfsd_acl_count2,
387 	.vs_dispatch	= nfsd_dispatch,
388 	.vs_xdrsize	= NFS3_SVC_XDRSIZE,
389 };
390