xref: /openbmc/linux/fs/nfsd/nfs2acl.c (revision 8e9356c6)
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, void *argp, void *resp)
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 		struct nfsd3_getaclargs *argp, struct nfsd3_getaclres *resp)
32 {
33 	struct posix_acl *acl;
34 	struct inode *inode;
35 	svc_fh *fh;
36 	__be32 nfserr = 0;
37 
38 	dprintk("nfsd: GETACL(2acl)   %s\n", SVCFH_fmt(&argp->fh));
39 
40 	fh = fh_copy(&resp->fh, &argp->fh);
41 	nfserr = fh_verify(rqstp, &resp->fh, 0, NFSD_MAY_NOP);
42 	if (nfserr)
43 		RETURN_STATUS(nfserr);
44 
45 	inode = fh->fh_dentry->d_inode;
46 
47 	if (argp->mask & ~(NFS_ACL|NFS_ACLCNT|NFS_DFACL|NFS_DFACLCNT))
48 		RETURN_STATUS(nfserr_inval);
49 	resp->mask = argp->mask;
50 
51 	nfserr = fh_getattr(fh, &resp->stat);
52 	if (nfserr)
53 		goto fail;
54 
55 	if (resp->mask & (NFS_ACL|NFS_ACLCNT)) {
56 		acl = get_acl(inode, ACL_TYPE_ACCESS);
57 		if (IS_ERR(acl)) {
58 			nfserr = nfserrno(PTR_ERR(acl));
59 			goto fail;
60 		}
61 		if (acl == NULL) {
62 			/* Solaris returns the inode's minimum ACL. */
63 			acl = posix_acl_from_mode(inode->i_mode, GFP_KERNEL);
64 		}
65 		resp->acl_access = acl;
66 	}
67 	if (resp->mask & (NFS_DFACL|NFS_DFACLCNT)) {
68 		/* Check how Solaris handles requests for the Default ACL
69 		   of a non-directory! */
70 		acl = get_acl(inode, ACL_TYPE_DEFAULT);
71 		if (IS_ERR(acl)) {
72 			nfserr = nfserrno(PTR_ERR(acl));
73 			goto fail;
74 		}
75 		resp->acl_default = acl;
76 	}
77 
78 	/* resp->acl_{access,default} are released in nfssvc_release_getacl. */
79 	RETURN_STATUS(0);
80 
81 fail:
82 	posix_acl_release(resp->acl_access);
83 	posix_acl_release(resp->acl_default);
84 	RETURN_STATUS(nfserr);
85 }
86 
87 /*
88  * Set the Access and/or Default ACL of a file.
89  */
90 static __be32 nfsacld_proc_setacl(struct svc_rqst * rqstp,
91 		struct nfsd3_setaclargs *argp,
92 		struct nfsd_attrstat *resp)
93 {
94 	struct inode *inode;
95 	svc_fh *fh;
96 	__be32 nfserr = 0;
97 	int error;
98 
99 	dprintk("nfsd: SETACL(2acl)   %s\n", SVCFH_fmt(&argp->fh));
100 
101 	fh = fh_copy(&resp->fh, &argp->fh);
102 	nfserr = fh_verify(rqstp, &resp->fh, 0, NFSD_MAY_SATTR);
103 	if (nfserr)
104 		goto out;
105 
106 	inode = fh->fh_dentry->d_inode;
107 	if (!IS_POSIXACL(inode) || !inode->i_op->set_acl) {
108 		error = -EOPNOTSUPP;
109 		goto out_errno;
110 	}
111 
112 	error = fh_want_write(fh);
113 	if (error)
114 		goto out_errno;
115 
116 	error = inode->i_op->set_acl(inode, argp->acl_access, ACL_TYPE_ACCESS);
117 	if (error)
118 		goto out_drop_write;
119 	error = inode->i_op->set_acl(inode, argp->acl_default,
120 				     ACL_TYPE_DEFAULT);
121 	if (error)
122 		goto out_drop_write;
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_write:
135 	fh_drop_write(fh);
136 out_errno:
137 	nfserr = nfserrno(error);
138 	goto out;
139 }
140 
141 /*
142  * Check file attributes
143  */
144 static __be32 nfsacld_proc_getattr(struct svc_rqst * rqstp,
145 		struct nfsd_fhandle *argp, struct nfsd_attrstat *resp)
146 {
147 	__be32 nfserr;
148 	dprintk("nfsd: GETATTR  %s\n", SVCFH_fmt(&argp->fh));
149 
150 	fh_copy(&resp->fh, &argp->fh);
151 	nfserr = fh_verify(rqstp, &resp->fh, 0, NFSD_MAY_NOP);
152 	if (nfserr)
153 		return nfserr;
154 	nfserr = fh_getattr(&resp->fh, &resp->stat);
155 	return nfserr;
156 }
157 
158 /*
159  * Check file access
160  */
161 static __be32 nfsacld_proc_access(struct svc_rqst *rqstp, struct nfsd3_accessargs *argp,
162 		struct nfsd3_accessres *resp)
163 {
164 	__be32 nfserr;
165 
166 	dprintk("nfsd: ACCESS(2acl)   %s 0x%x\n",
167 			SVCFH_fmt(&argp->fh),
168 			argp->access);
169 
170 	fh_copy(&resp->fh, &argp->fh);
171 	resp->access = argp->access;
172 	nfserr = nfsd_access(rqstp, &resp->fh, &resp->access, NULL);
173 	if (nfserr)
174 		return nfserr;
175 	nfserr = fh_getattr(&resp->fh, &resp->stat);
176 	return nfserr;
177 }
178 
179 /*
180  * XDR decode functions
181  */
182 static int nfsaclsvc_decode_getaclargs(struct svc_rqst *rqstp, __be32 *p,
183 		struct nfsd3_getaclargs *argp)
184 {
185 	if (!(p = nfs2svc_decode_fh(p, &argp->fh)))
186 		return 0;
187 	argp->mask = ntohl(*p); p++;
188 
189 	return xdr_argsize_check(rqstp, p);
190 }
191 
192 
193 static int nfsaclsvc_decode_setaclargs(struct svc_rqst *rqstp, __be32 *p,
194 		struct nfsd3_setaclargs *argp)
195 {
196 	struct kvec *head = rqstp->rq_arg.head;
197 	unsigned int base;
198 	int n;
199 
200 	if (!(p = nfs2svc_decode_fh(p, &argp->fh)))
201 		return 0;
202 	argp->mask = ntohl(*p++);
203 	if (argp->mask & ~(NFS_ACL|NFS_ACLCNT|NFS_DFACL|NFS_DFACLCNT) ||
204 	    !xdr_argsize_check(rqstp, p))
205 		return 0;
206 
207 	base = (char *)p - (char *)head->iov_base;
208 	n = nfsacl_decode(&rqstp->rq_arg, base, NULL,
209 			  (argp->mask & NFS_ACL) ?
210 			  &argp->acl_access : NULL);
211 	if (n > 0)
212 		n = nfsacl_decode(&rqstp->rq_arg, base + n, NULL,
213 				  (argp->mask & NFS_DFACL) ?
214 				  &argp->acl_default : NULL);
215 	return (n > 0);
216 }
217 
218 static int nfsaclsvc_decode_fhandleargs(struct svc_rqst *rqstp, __be32 *p,
219 		struct nfsd_fhandle *argp)
220 {
221 	if (!(p = nfs2svc_decode_fh(p, &argp->fh)))
222 		return 0;
223 	return xdr_argsize_check(rqstp, p);
224 }
225 
226 static int nfsaclsvc_decode_accessargs(struct svc_rqst *rqstp, __be32 *p,
227 		struct nfsd3_accessargs *argp)
228 {
229 	if (!(p = nfs2svc_decode_fh(p, &argp->fh)))
230 		return 0;
231 	argp->access = ntohl(*p++);
232 
233 	return xdr_argsize_check(rqstp, p);
234 }
235 
236 /*
237  * XDR encode functions
238  */
239 
240 /*
241  * There must be an encoding function for void results so svc_process
242  * will work properly.
243  */
244 static int nfsaclsvc_encode_voidres(struct svc_rqst *rqstp, __be32 *p, void *dummy)
245 {
246 	return xdr_ressize_check(rqstp, p);
247 }
248 
249 /* GETACL */
250 static int nfsaclsvc_encode_getaclres(struct svc_rqst *rqstp, __be32 *p,
251 		struct nfsd3_getaclres *resp)
252 {
253 	struct dentry *dentry = resp->fh.fh_dentry;
254 	struct inode *inode;
255 	struct kvec *head = rqstp->rq_res.head;
256 	unsigned int base;
257 	int n;
258 	int w;
259 
260 	/*
261 	 * Since this is version 2, the check for nfserr in
262 	 * nfsd_dispatch actually ensures the following cannot happen.
263 	 * However, it seems fragile to depend on that.
264 	 */
265 	if (dentry == NULL || dentry->d_inode == NULL)
266 		return 0;
267 	inode = dentry->d_inode;
268 
269 	p = nfs2svc_encode_fattr(rqstp, p, &resp->fh, &resp->stat);
270 	*p++ = htonl(resp->mask);
271 	if (!xdr_ressize_check(rqstp, p))
272 		return 0;
273 	base = (char *)p - (char *)head->iov_base;
274 
275 	rqstp->rq_res.page_len = w = nfsacl_size(
276 		(resp->mask & NFS_ACL)   ? resp->acl_access  : NULL,
277 		(resp->mask & NFS_DFACL) ? resp->acl_default : NULL);
278 	while (w > 0) {
279 		if (!*(rqstp->rq_next_page++))
280 			return 0;
281 		w -= PAGE_SIZE;
282 	}
283 
284 	n = nfsacl_encode(&rqstp->rq_res, base, inode,
285 			  resp->acl_access,
286 			  resp->mask & NFS_ACL, 0);
287 	if (n > 0)
288 		n = nfsacl_encode(&rqstp->rq_res, base + n, inode,
289 				  resp->acl_default,
290 				  resp->mask & NFS_DFACL,
291 				  NFS_ACL_DEFAULT);
292 	if (n <= 0)
293 		return 0;
294 	return 1;
295 }
296 
297 static int nfsaclsvc_encode_attrstatres(struct svc_rqst *rqstp, __be32 *p,
298 		struct nfsd_attrstat *resp)
299 {
300 	p = nfs2svc_encode_fattr(rqstp, p, &resp->fh, &resp->stat);
301 	return xdr_ressize_check(rqstp, p);
302 }
303 
304 /* ACCESS */
305 static int nfsaclsvc_encode_accessres(struct svc_rqst *rqstp, __be32 *p,
306 		struct nfsd3_accessres *resp)
307 {
308 	p = nfs2svc_encode_fattr(rqstp, p, &resp->fh, &resp->stat);
309 	*p++ = htonl(resp->access);
310 	return xdr_ressize_check(rqstp, p);
311 }
312 
313 /*
314  * XDR release functions
315  */
316 static int nfsaclsvc_release_getacl(struct svc_rqst *rqstp, __be32 *p,
317 		struct nfsd3_getaclres *resp)
318 {
319 	fh_put(&resp->fh);
320 	posix_acl_release(resp->acl_access);
321 	posix_acl_release(resp->acl_default);
322 	return 1;
323 }
324 
325 static int nfsaclsvc_release_attrstat(struct svc_rqst *rqstp, __be32 *p,
326 		struct nfsd_attrstat *resp)
327 {
328 	fh_put(&resp->fh);
329 	return 1;
330 }
331 
332 static int nfsaclsvc_release_access(struct svc_rqst *rqstp, __be32 *p,
333                struct nfsd3_accessres *resp)
334 {
335        fh_put(&resp->fh);
336        return 1;
337 }
338 
339 #define nfsaclsvc_decode_voidargs	NULL
340 #define nfsaclsvc_release_void		NULL
341 #define nfsd3_fhandleargs	nfsd_fhandle
342 #define nfsd3_attrstatres	nfsd_attrstat
343 #define nfsd3_voidres		nfsd3_voidargs
344 struct nfsd3_voidargs { int dummy; };
345 
346 #define PROC(name, argt, rest, relt, cache, respsize)	\
347  { (svc_procfunc) nfsacld_proc_##name,		\
348    (kxdrproc_t) nfsaclsvc_decode_##argt##args,	\
349    (kxdrproc_t) nfsaclsvc_encode_##rest##res,	\
350    (kxdrproc_t) nfsaclsvc_release_##relt,		\
351    sizeof(struct nfsd3_##argt##args),		\
352    sizeof(struct nfsd3_##rest##res),		\
353    0,						\
354    cache,					\
355    respsize,					\
356  }
357 
358 #define ST 1		/* status*/
359 #define AT 21		/* attributes */
360 #define pAT (1+AT)	/* post attributes - conditional */
361 #define ACL (1+NFS_ACL_MAX_ENTRIES*3)  /* Access Control List */
362 
363 static struct svc_procedure		nfsd_acl_procedures2[] = {
364   PROC(null,	void,		void,		void,	  RC_NOCACHE, ST),
365   PROC(getacl,	getacl,		getacl,		getacl,	  RC_NOCACHE, ST+1+2*(1+ACL)),
366   PROC(setacl,	setacl,		attrstat,	attrstat, RC_NOCACHE, ST+AT),
367   PROC(getattr, fhandle,	attrstat,	attrstat, RC_NOCACHE, ST+AT),
368   PROC(access,	access,		access,		access,   RC_NOCACHE, ST+AT+1),
369 };
370 
371 struct svc_version	nfsd_acl_version2 = {
372 		.vs_vers	= 2,
373 		.vs_nproc	= 5,
374 		.vs_proc	= nfsd_acl_procedures2,
375 		.vs_dispatch	= nfsd_dispatch,
376 		.vs_xdrsize	= NFS3_SVC_XDRSIZE,
377 		.vs_hidden	= 0,
378 };
379