xref: /linux/fs/nfsd/nfs2acl.c (revision 0dd9ac63ce26ec87b080ca9c3e6efed33c23ace6)
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 	svc_fh *fh;
34 	struct posix_acl *acl;
35 	__be32 nfserr = 0;
36 
37 	dprintk("nfsd: GETACL(2acl)   %s\n", SVCFH_fmt(&argp->fh));
38 
39 	fh = fh_copy(&resp->fh, &argp->fh);
40 	nfserr = fh_verify(rqstp, &resp->fh, 0, NFSD_MAY_NOP);
41 	if (nfserr)
42 		RETURN_STATUS(nfserr);
43 
44 	if (argp->mask & ~(NFS_ACL|NFS_ACLCNT|NFS_DFACL|NFS_DFACLCNT))
45 		RETURN_STATUS(nfserr_inval);
46 	resp->mask = argp->mask;
47 
48 	if (resp->mask & (NFS_ACL|NFS_ACLCNT)) {
49 		acl = nfsd_get_posix_acl(fh, ACL_TYPE_ACCESS);
50 		if (IS_ERR(acl)) {
51 			int err = PTR_ERR(acl);
52 
53 			if (err == -ENODATA || err == -EOPNOTSUPP)
54 				acl = NULL;
55 			else {
56 				nfserr = nfserrno(err);
57 				goto fail;
58 			}
59 		}
60 		if (acl == NULL) {
61 			/* Solaris returns the inode's minimum ACL. */
62 
63 			struct inode *inode = fh->fh_dentry->d_inode;
64 			acl = posix_acl_from_mode(inode->i_mode, GFP_KERNEL);
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 
72 		acl = nfsd_get_posix_acl(fh, ACL_TYPE_DEFAULT);
73 		if (IS_ERR(acl)) {
74 			int err = PTR_ERR(acl);
75 
76 			if (err == -ENODATA || err == -EOPNOTSUPP)
77 				acl = NULL;
78 			else {
79 				nfserr = nfserrno(err);
80 				goto fail;
81 			}
82 		}
83 		resp->acl_default = acl;
84 	}
85 
86 	/* resp->acl_{access,default} are released in nfssvc_release_getacl. */
87 	RETURN_STATUS(0);
88 
89 fail:
90 	posix_acl_release(resp->acl_access);
91 	posix_acl_release(resp->acl_default);
92 	RETURN_STATUS(nfserr);
93 }
94 
95 /*
96  * Set the Access and/or Default ACL of a file.
97  */
98 static __be32 nfsacld_proc_setacl(struct svc_rqst * rqstp,
99 		struct nfsd3_setaclargs *argp,
100 		struct nfsd_attrstat *resp)
101 {
102 	svc_fh *fh;
103 	__be32 nfserr = 0;
104 
105 	dprintk("nfsd: SETACL(2acl)   %s\n", SVCFH_fmt(&argp->fh));
106 
107 	fh = fh_copy(&resp->fh, &argp->fh);
108 	nfserr = fh_verify(rqstp, &resp->fh, 0, NFSD_MAY_SATTR);
109 
110 	if (!nfserr) {
111 		nfserr = nfserrno( nfsd_set_posix_acl(
112 			fh, ACL_TYPE_ACCESS, argp->acl_access) );
113 	}
114 	if (!nfserr) {
115 		nfserr = nfserrno( nfsd_set_posix_acl(
116 			fh, ACL_TYPE_DEFAULT, argp->acl_default) );
117 	}
118 
119 	/* argp->acl_{access,default} may have been allocated in
120 	   nfssvc_decode_setaclargs. */
121 	posix_acl_release(argp->acl_access);
122 	posix_acl_release(argp->acl_default);
123 	return nfserr;
124 }
125 
126 /*
127  * Check file attributes
128  */
129 static __be32 nfsacld_proc_getattr(struct svc_rqst * rqstp,
130 		struct nfsd_fhandle *argp, struct nfsd_attrstat *resp)
131 {
132 	dprintk("nfsd: GETATTR  %s\n", SVCFH_fmt(&argp->fh));
133 
134 	fh_copy(&resp->fh, &argp->fh);
135 	return fh_verify(rqstp, &resp->fh, 0, NFSD_MAY_NOP);
136 }
137 
138 /*
139  * Check file access
140  */
141 static __be32 nfsacld_proc_access(struct svc_rqst *rqstp, struct nfsd3_accessargs *argp,
142 		struct nfsd3_accessres *resp)
143 {
144 	__be32 nfserr;
145 
146 	dprintk("nfsd: ACCESS(2acl)   %s 0x%x\n",
147 			SVCFH_fmt(&argp->fh),
148 			argp->access);
149 
150 	fh_copy(&resp->fh, &argp->fh);
151 	resp->access = argp->access;
152 	nfserr = nfsd_access(rqstp, &resp->fh, &resp->access, NULL);
153 	return nfserr;
154 }
155 
156 /*
157  * XDR decode functions
158  */
159 static int nfsaclsvc_decode_getaclargs(struct svc_rqst *rqstp, __be32 *p,
160 		struct nfsd3_getaclargs *argp)
161 {
162 	if (!(p = nfs2svc_decode_fh(p, &argp->fh)))
163 		return 0;
164 	argp->mask = ntohl(*p); p++;
165 
166 	return xdr_argsize_check(rqstp, p);
167 }
168 
169 
170 static int nfsaclsvc_decode_setaclargs(struct svc_rqst *rqstp, __be32 *p,
171 		struct nfsd3_setaclargs *argp)
172 {
173 	struct kvec *head = rqstp->rq_arg.head;
174 	unsigned int base;
175 	int n;
176 
177 	if (!(p = nfs2svc_decode_fh(p, &argp->fh)))
178 		return 0;
179 	argp->mask = ntohl(*p++);
180 	if (argp->mask & ~(NFS_ACL|NFS_ACLCNT|NFS_DFACL|NFS_DFACLCNT) ||
181 	    !xdr_argsize_check(rqstp, p))
182 		return 0;
183 
184 	base = (char *)p - (char *)head->iov_base;
185 	n = nfsacl_decode(&rqstp->rq_arg, base, NULL,
186 			  (argp->mask & NFS_ACL) ?
187 			  &argp->acl_access : NULL);
188 	if (n > 0)
189 		n = nfsacl_decode(&rqstp->rq_arg, base + n, NULL,
190 				  (argp->mask & NFS_DFACL) ?
191 				  &argp->acl_default : NULL);
192 	return (n > 0);
193 }
194 
195 static int nfsaclsvc_decode_fhandleargs(struct svc_rqst *rqstp, __be32 *p,
196 		struct nfsd_fhandle *argp)
197 {
198 	if (!(p = nfs2svc_decode_fh(p, &argp->fh)))
199 		return 0;
200 	return xdr_argsize_check(rqstp, p);
201 }
202 
203 static int nfsaclsvc_decode_accessargs(struct svc_rqst *rqstp, __be32 *p,
204 		struct nfsd3_accessargs *argp)
205 {
206 	if (!(p = nfs2svc_decode_fh(p, &argp->fh)))
207 		return 0;
208 	argp->access = ntohl(*p++);
209 
210 	return xdr_argsize_check(rqstp, p);
211 }
212 
213 /*
214  * XDR encode functions
215  */
216 
217 /*
218  * There must be an encoding function for void results so svc_process
219  * will work properly.
220  */
221 int
222 nfsaclsvc_encode_voidres(struct svc_rqst *rqstp, __be32 *p, void *dummy)
223 {
224 	return xdr_ressize_check(rqstp, p);
225 }
226 
227 /* GETACL */
228 static int nfsaclsvc_encode_getaclres(struct svc_rqst *rqstp, __be32 *p,
229 		struct nfsd3_getaclres *resp)
230 {
231 	struct dentry *dentry = resp->fh.fh_dentry;
232 	struct inode *inode;
233 	struct kvec *head = rqstp->rq_res.head;
234 	unsigned int base;
235 	int n;
236 	int w;
237 
238 	/*
239 	 * Since this is version 2, the check for nfserr in
240 	 * nfsd_dispatch actually ensures the following cannot happen.
241 	 * However, it seems fragile to depend on that.
242 	 */
243 	if (dentry == NULL || dentry->d_inode == NULL)
244 		return 0;
245 	inode = dentry->d_inode;
246 
247 	p = nfs2svc_encode_fattr(rqstp, p, &resp->fh);
248 	*p++ = htonl(resp->mask);
249 	if (!xdr_ressize_check(rqstp, p))
250 		return 0;
251 	base = (char *)p - (char *)head->iov_base;
252 
253 	rqstp->rq_res.page_len = w = nfsacl_size(
254 		(resp->mask & NFS_ACL)   ? resp->acl_access  : NULL,
255 		(resp->mask & NFS_DFACL) ? resp->acl_default : NULL);
256 	while (w > 0) {
257 		if (!rqstp->rq_respages[rqstp->rq_resused++])
258 			return 0;
259 		w -= PAGE_SIZE;
260 	}
261 
262 	n = nfsacl_encode(&rqstp->rq_res, base, inode,
263 			  resp->acl_access,
264 			  resp->mask & NFS_ACL, 0);
265 	if (n > 0)
266 		n = nfsacl_encode(&rqstp->rq_res, base + n, inode,
267 				  resp->acl_default,
268 				  resp->mask & NFS_DFACL,
269 				  NFS_ACL_DEFAULT);
270 	if (n <= 0)
271 		return 0;
272 	return 1;
273 }
274 
275 static int nfsaclsvc_encode_attrstatres(struct svc_rqst *rqstp, __be32 *p,
276 		struct nfsd_attrstat *resp)
277 {
278 	p = nfs2svc_encode_fattr(rqstp, p, &resp->fh);
279 	return xdr_ressize_check(rqstp, p);
280 }
281 
282 /* ACCESS */
283 static int nfsaclsvc_encode_accessres(struct svc_rqst *rqstp, __be32 *p,
284 		struct nfsd3_accessres *resp)
285 {
286 	p = nfs2svc_encode_fattr(rqstp, p, &resp->fh);
287 	*p++ = htonl(resp->access);
288 	return xdr_ressize_check(rqstp, p);
289 }
290 
291 /*
292  * XDR release functions
293  */
294 static int nfsaclsvc_release_getacl(struct svc_rqst *rqstp, __be32 *p,
295 		struct nfsd3_getaclres *resp)
296 {
297 	fh_put(&resp->fh);
298 	posix_acl_release(resp->acl_access);
299 	posix_acl_release(resp->acl_default);
300 	return 1;
301 }
302 
303 static int nfsaclsvc_release_attrstat(struct svc_rqst *rqstp, __be32 *p,
304 		struct nfsd_attrstat *resp)
305 {
306 	fh_put(&resp->fh);
307 	return 1;
308 }
309 
310 static int nfsaclsvc_release_access(struct svc_rqst *rqstp, __be32 *p,
311                struct nfsd3_accessres *resp)
312 {
313        fh_put(&resp->fh);
314        return 1;
315 }
316 
317 #define nfsaclsvc_decode_voidargs	NULL
318 #define nfsaclsvc_release_void		NULL
319 #define nfsd3_fhandleargs	nfsd_fhandle
320 #define nfsd3_attrstatres	nfsd_attrstat
321 #define nfsd3_voidres		nfsd3_voidargs
322 struct nfsd3_voidargs { int dummy; };
323 
324 #define PROC(name, argt, rest, relt, cache, respsize)	\
325  { (svc_procfunc) nfsacld_proc_##name,		\
326    (kxdrproc_t) nfsaclsvc_decode_##argt##args,	\
327    (kxdrproc_t) nfsaclsvc_encode_##rest##res,	\
328    (kxdrproc_t) nfsaclsvc_release_##relt,		\
329    sizeof(struct nfsd3_##argt##args),		\
330    sizeof(struct nfsd3_##rest##res),		\
331    0,						\
332    cache,					\
333    respsize,					\
334  }
335 
336 #define ST 1		/* status*/
337 #define AT 21		/* attributes */
338 #define pAT (1+AT)	/* post attributes - conditional */
339 #define ACL (1+NFS_ACL_MAX_ENTRIES*3)  /* Access Control List */
340 
341 static struct svc_procedure		nfsd_acl_procedures2[] = {
342   PROC(null,	void,		void,		void,	  RC_NOCACHE, ST),
343   PROC(getacl,	getacl,		getacl,		getacl,	  RC_NOCACHE, ST+1+2*(1+ACL)),
344   PROC(setacl,	setacl,		attrstat,	attrstat, RC_NOCACHE, ST+AT),
345   PROC(getattr, fhandle,	attrstat,	attrstat, RC_NOCACHE, ST+AT),
346   PROC(access,	access,		access,		access,   RC_NOCACHE, ST+AT+1),
347 };
348 
349 struct svc_version	nfsd_acl_version2 = {
350 		.vs_vers	= 2,
351 		.vs_nproc	= 5,
352 		.vs_proc	= nfsd_acl_procedures2,
353 		.vs_dispatch	= nfsd_dispatch,
354 		.vs_xdrsize	= NFS3_SVC_XDRSIZE,
355 		.vs_hidden	= 0,
356 };
357