xref: /openbmc/linux/fs/nfsd/nfs2acl.c (revision 367b8112)
1 /*
2  * linux/fs/nfsd/nfs2acl.c
3  *
4  * Process version 2 NFSACL requests.
5  *
6  * Copyright (C) 2002-2003 Andreas Gruenbacher <agruen@suse.de>
7  */
8 
9 #include <linux/sunrpc/svc.h>
10 #include <linux/nfs.h>
11 #include <linux/nfsd/nfsd.h>
12 #include <linux/nfsd/cache.h>
13 #include <linux/nfsd/xdr.h>
14 #include <linux/nfsd/xdr3.h>
15 #include <linux/posix_acl.h>
16 #include <linux/nfsacl.h>
17 
18 #define NFSDDBG_FACILITY		NFSDDBG_PROC
19 #define RETURN_STATUS(st)	{ resp->status = (st); return (st); }
20 
21 /*
22  * NULL call.
23  */
24 static __be32
25 nfsacld_proc_null(struct svc_rqst *rqstp, void *argp, void *resp)
26 {
27 	return nfs_ok;
28 }
29 
30 /*
31  * Get the Access and/or Default ACL of a file.
32  */
33 static __be32 nfsacld_proc_getacl(struct svc_rqst * rqstp,
34 		struct nfsd3_getaclargs *argp, struct nfsd3_getaclres *resp)
35 {
36 	svc_fh *fh;
37 	struct posix_acl *acl;
38 	__be32 nfserr = 0;
39 
40 	dprintk("nfsd: GETACL(2acl)   %s\n", SVCFH_fmt(&argp->fh));
41 
42 	fh = fh_copy(&resp->fh, &argp->fh);
43 	nfserr = fh_verify(rqstp, &resp->fh, 0, NFSD_MAY_NOP);
44 	if (nfserr)
45 		RETURN_STATUS(nfserr);
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 	if (resp->mask & (NFS_ACL|NFS_ACLCNT)) {
52 		acl = nfsd_get_posix_acl(fh, ACL_TYPE_ACCESS);
53 		if (IS_ERR(acl)) {
54 			int err = PTR_ERR(acl);
55 
56 			if (err == -ENODATA || err == -EOPNOTSUPP)
57 				acl = NULL;
58 			else {
59 				nfserr = nfserrno(err);
60 				goto fail;
61 			}
62 		}
63 		if (acl == NULL) {
64 			/* Solaris returns the inode's minimum ACL. */
65 
66 			struct inode *inode = fh->fh_dentry->d_inode;
67 			acl = posix_acl_from_mode(inode->i_mode, GFP_KERNEL);
68 		}
69 		resp->acl_access = acl;
70 	}
71 	if (resp->mask & (NFS_DFACL|NFS_DFACLCNT)) {
72 		/* Check how Solaris handles requests for the Default ACL
73 		   of a non-directory! */
74 
75 		acl = nfsd_get_posix_acl(fh, ACL_TYPE_DEFAULT);
76 		if (IS_ERR(acl)) {
77 			int err = PTR_ERR(acl);
78 
79 			if (err == -ENODATA || err == -EOPNOTSUPP)
80 				acl = NULL;
81 			else {
82 				nfserr = nfserrno(err);
83 				goto fail;
84 			}
85 		}
86 		resp->acl_default = acl;
87 	}
88 
89 	/* resp->acl_{access,default} are released in nfssvc_release_getacl. */
90 	RETURN_STATUS(0);
91 
92 fail:
93 	posix_acl_release(resp->acl_access);
94 	posix_acl_release(resp->acl_default);
95 	RETURN_STATUS(nfserr);
96 }
97 
98 /*
99  * Set the Access and/or Default ACL of a file.
100  */
101 static __be32 nfsacld_proc_setacl(struct svc_rqst * rqstp,
102 		struct nfsd3_setaclargs *argp,
103 		struct nfsd_attrstat *resp)
104 {
105 	svc_fh *fh;
106 	__be32 nfserr = 0;
107 
108 	dprintk("nfsd: SETACL(2acl)   %s\n", SVCFH_fmt(&argp->fh));
109 
110 	fh = fh_copy(&resp->fh, &argp->fh);
111 	nfserr = fh_verify(rqstp, &resp->fh, 0, NFSD_MAY_SATTR);
112 
113 	if (!nfserr) {
114 		nfserr = nfserrno( nfsd_set_posix_acl(
115 			fh, ACL_TYPE_ACCESS, argp->acl_access) );
116 	}
117 	if (!nfserr) {
118 		nfserr = nfserrno( nfsd_set_posix_acl(
119 			fh, ACL_TYPE_DEFAULT, argp->acl_default) );
120 	}
121 
122 	/* argp->acl_{access,default} may have been allocated in
123 	   nfssvc_decode_setaclargs. */
124 	posix_acl_release(argp->acl_access);
125 	posix_acl_release(argp->acl_default);
126 	return nfserr;
127 }
128 
129 /*
130  * Check file attributes
131  */
132 static __be32 nfsacld_proc_getattr(struct svc_rqst * rqstp,
133 		struct nfsd_fhandle *argp, struct nfsd_attrstat *resp)
134 {
135 	dprintk("nfsd: GETATTR  %s\n", SVCFH_fmt(&argp->fh));
136 
137 	fh_copy(&resp->fh, &argp->fh);
138 	return fh_verify(rqstp, &resp->fh, 0, NFSD_MAY_NOP);
139 }
140 
141 /*
142  * Check file access
143  */
144 static __be32 nfsacld_proc_access(struct svc_rqst *rqstp, struct nfsd3_accessargs *argp,
145 		struct nfsd3_accessres *resp)
146 {
147 	__be32 nfserr;
148 
149 	dprintk("nfsd: ACCESS(2acl)   %s 0x%x\n",
150 			SVCFH_fmt(&argp->fh),
151 			argp->access);
152 
153 	fh_copy(&resp->fh, &argp->fh);
154 	resp->access = argp->access;
155 	nfserr = nfsd_access(rqstp, &resp->fh, &resp->access, NULL);
156 	return nfserr;
157 }
158 
159 /*
160  * XDR decode functions
161  */
162 static int nfsaclsvc_decode_getaclargs(struct svc_rqst *rqstp, __be32 *p,
163 		struct nfsd3_getaclargs *argp)
164 {
165 	if (!(p = nfs2svc_decode_fh(p, &argp->fh)))
166 		return 0;
167 	argp->mask = ntohl(*p); p++;
168 
169 	return xdr_argsize_check(rqstp, p);
170 }
171 
172 
173 static int nfsaclsvc_decode_setaclargs(struct svc_rqst *rqstp, __be32 *p,
174 		struct nfsd3_setaclargs *argp)
175 {
176 	struct kvec *head = rqstp->rq_arg.head;
177 	unsigned int base;
178 	int n;
179 
180 	if (!(p = nfs2svc_decode_fh(p, &argp->fh)))
181 		return 0;
182 	argp->mask = ntohl(*p++);
183 	if (argp->mask & ~(NFS_ACL|NFS_ACLCNT|NFS_DFACL|NFS_DFACLCNT) ||
184 	    !xdr_argsize_check(rqstp, p))
185 		return 0;
186 
187 	base = (char *)p - (char *)head->iov_base;
188 	n = nfsacl_decode(&rqstp->rq_arg, base, NULL,
189 			  (argp->mask & NFS_ACL) ?
190 			  &argp->acl_access : NULL);
191 	if (n > 0)
192 		n = nfsacl_decode(&rqstp->rq_arg, base + n, NULL,
193 				  (argp->mask & NFS_DFACL) ?
194 				  &argp->acl_default : NULL);
195 	return (n > 0);
196 }
197 
198 static int nfsaclsvc_decode_fhandleargs(struct svc_rqst *rqstp, __be32 *p,
199 		struct nfsd_fhandle *argp)
200 {
201 	if (!(p = nfs2svc_decode_fh(p, &argp->fh)))
202 		return 0;
203 	return xdr_argsize_check(rqstp, p);
204 }
205 
206 static int nfsaclsvc_decode_accessargs(struct svc_rqst *rqstp, __be32 *p,
207 		struct nfsd3_accessargs *argp)
208 {
209 	if (!(p = nfs2svc_decode_fh(p, &argp->fh)))
210 		return 0;
211 	argp->access = ntohl(*p++);
212 
213 	return xdr_argsize_check(rqstp, p);
214 }
215 
216 /*
217  * XDR encode functions
218  */
219 
220 /* GETACL */
221 static int nfsaclsvc_encode_getaclres(struct svc_rqst *rqstp, __be32 *p,
222 		struct nfsd3_getaclres *resp)
223 {
224 	struct dentry *dentry = resp->fh.fh_dentry;
225 	struct inode *inode;
226 	struct kvec *head = rqstp->rq_res.head;
227 	unsigned int base;
228 	int n;
229 	int w;
230 
231 	/*
232 	 * Since this is version 2, the check for nfserr in
233 	 * nfsd_dispatch actually ensures the following cannot happen.
234 	 * However, it seems fragile to depend on that.
235 	 */
236 	if (dentry == NULL || dentry->d_inode == NULL)
237 		return 0;
238 	inode = dentry->d_inode;
239 
240 	p = nfs2svc_encode_fattr(rqstp, p, &resp->fh);
241 	*p++ = htonl(resp->mask);
242 	if (!xdr_ressize_check(rqstp, p))
243 		return 0;
244 	base = (char *)p - (char *)head->iov_base;
245 
246 	rqstp->rq_res.page_len = w = nfsacl_size(
247 		(resp->mask & NFS_ACL)   ? resp->acl_access  : NULL,
248 		(resp->mask & NFS_DFACL) ? resp->acl_default : NULL);
249 	while (w > 0) {
250 		if (!rqstp->rq_respages[rqstp->rq_resused++])
251 			return 0;
252 		w -= PAGE_SIZE;
253 	}
254 
255 	n = nfsacl_encode(&rqstp->rq_res, base, inode,
256 			  resp->acl_access,
257 			  resp->mask & NFS_ACL, 0);
258 	if (n > 0)
259 		n = nfsacl_encode(&rqstp->rq_res, base + n, inode,
260 				  resp->acl_default,
261 				  resp->mask & NFS_DFACL,
262 				  NFS_ACL_DEFAULT);
263 	if (n <= 0)
264 		return 0;
265 	return 1;
266 }
267 
268 static int nfsaclsvc_encode_attrstatres(struct svc_rqst *rqstp, __be32 *p,
269 		struct nfsd_attrstat *resp)
270 {
271 	p = nfs2svc_encode_fattr(rqstp, p, &resp->fh);
272 	return xdr_ressize_check(rqstp, p);
273 }
274 
275 /* ACCESS */
276 static int nfsaclsvc_encode_accessres(struct svc_rqst *rqstp, __be32 *p,
277 		struct nfsd3_accessres *resp)
278 {
279 	p = nfs2svc_encode_fattr(rqstp, p, &resp->fh);
280 	*p++ = htonl(resp->access);
281 	return xdr_ressize_check(rqstp, p);
282 }
283 
284 /*
285  * XDR release functions
286  */
287 static int nfsaclsvc_release_getacl(struct svc_rqst *rqstp, __be32 *p,
288 		struct nfsd3_getaclres *resp)
289 {
290 	fh_put(&resp->fh);
291 	posix_acl_release(resp->acl_access);
292 	posix_acl_release(resp->acl_default);
293 	return 1;
294 }
295 
296 static int nfsaclsvc_release_attrstat(struct svc_rqst *rqstp, __be32 *p,
297 		struct nfsd_attrstat *resp)
298 {
299 	fh_put(&resp->fh);
300 	return 1;
301 }
302 
303 static int nfsaclsvc_release_access(struct svc_rqst *rqstp, __be32 *p,
304                struct nfsd3_accessres *resp)
305 {
306        fh_put(&resp->fh);
307        return 1;
308 }
309 
310 #define nfsaclsvc_decode_voidargs	NULL
311 #define nfsaclsvc_encode_voidres	NULL
312 #define nfsaclsvc_release_void		NULL
313 #define nfsd3_fhandleargs	nfsd_fhandle
314 #define nfsd3_attrstatres	nfsd_attrstat
315 #define nfsd3_voidres		nfsd3_voidargs
316 struct nfsd3_voidargs { int dummy; };
317 
318 #define PROC(name, argt, rest, relt, cache, respsize)	\
319  { (svc_procfunc) nfsacld_proc_##name,		\
320    (kxdrproc_t) nfsaclsvc_decode_##argt##args,	\
321    (kxdrproc_t) nfsaclsvc_encode_##rest##res,	\
322    (kxdrproc_t) nfsaclsvc_release_##relt,		\
323    sizeof(struct nfsd3_##argt##args),		\
324    sizeof(struct nfsd3_##rest##res),		\
325    0,						\
326    cache,					\
327    respsize,					\
328  }
329 
330 #define ST 1		/* status*/
331 #define AT 21		/* attributes */
332 #define pAT (1+AT)	/* post attributes - conditional */
333 #define ACL (1+NFS_ACL_MAX_ENTRIES*3)  /* Access Control List */
334 
335 static struct svc_procedure		nfsd_acl_procedures2[] = {
336   PROC(null,	void,		void,		void,	  RC_NOCACHE, ST),
337   PROC(getacl,	getacl,		getacl,		getacl,	  RC_NOCACHE, ST+1+2*(1+ACL)),
338   PROC(setacl,	setacl,		attrstat,	attrstat, RC_NOCACHE, ST+AT),
339   PROC(getattr, fhandle,	attrstat,	attrstat, RC_NOCACHE, ST+AT),
340   PROC(access,	access,		access,		access,   RC_NOCACHE, ST+AT+1),
341 };
342 
343 struct svc_version	nfsd_acl_version2 = {
344 		.vs_vers	= 2,
345 		.vs_nproc	= 5,
346 		.vs_proc	= nfsd_acl_procedures2,
347 		.vs_dispatch	= nfsd_dispatch,
348 		.vs_xdrsize	= NFS3_SVC_XDRSIZE,
349 		.vs_hidden	= 1,
350 };
351