xref: /linux/fs/nfsd/nfs3acl.c (revision 2fe05e1139a555ae91f00a812cb9520e7d3022ab)
1 /*
2  * Process version 3 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 RETURN_STATUS(st)	{ resp->status = (st); return (st); }
16 
17 /*
18  * NULL call.
19  */
20 static __be32
21 nfsd3_proc_null(struct svc_rqst *rqstp)
22 {
23 	return nfs_ok;
24 }
25 
26 /*
27  * Get the Access and/or Default ACL of a file.
28  */
29 static __be32 nfsd3_proc_getacl(struct svc_rqst *rqstp)
30 {
31 	struct nfsd3_getaclargs *argp = rqstp->rq_argp;
32 	struct nfsd3_getaclres *resp = rqstp->rq_resp;
33 	struct posix_acl *acl;
34 	struct inode *inode;
35 	svc_fh *fh;
36 	__be32 nfserr = 0;
37 
38 	fh = fh_copy(&resp->fh, &argp->fh);
39 	nfserr = fh_verify(rqstp, &resp->fh, 0, NFSD_MAY_NOP);
40 	if (nfserr)
41 		RETURN_STATUS(nfserr);
42 
43 	inode = d_inode(fh->fh_dentry);
44 
45 	if (argp->mask & ~NFS_ACL_MASK)
46 		RETURN_STATUS(nfserr_inval);
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 			nfserr = 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 			nfserr = 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 	RETURN_STATUS(0);
74 
75 fail:
76 	posix_acl_release(resp->acl_access);
77 	posix_acl_release(resp->acl_default);
78 	RETURN_STATUS(nfserr);
79 }
80 
81 /*
82  * Set the Access and/or Default ACL of a file.
83  */
84 static __be32 nfsd3_proc_setacl(struct svc_rqst *rqstp)
85 {
86 	struct nfsd3_setaclargs *argp = rqstp->rq_argp;
87 	struct nfsd3_attrstat *resp = rqstp->rq_resp;
88 	struct inode *inode;
89 	svc_fh *fh;
90 	__be32 nfserr = 0;
91 	int error;
92 
93 	fh = fh_copy(&resp->fh, &argp->fh);
94 	nfserr = fh_verify(rqstp, &resp->fh, 0, NFSD_MAY_SATTR);
95 	if (nfserr)
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 	nfserr = 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_STATUS(nfserr);
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 = nfs3svc_encode_post_op_attr(rqstp, p, &resp->fh);
177 	if (resp->status == 0 && dentry && d_really_is_positive(dentry)) {
178 		struct inode *inode = d_inode(dentry);
179 		struct kvec *head = rqstp->rq_res.head;
180 		unsigned int base;
181 		int n;
182 		int w;
183 
184 		*p++ = htonl(resp->mask);
185 		if (!xdr_ressize_check(rqstp, p))
186 			return 0;
187 		base = (char *)p - (char *)head->iov_base;
188 
189 		rqstp->rq_res.page_len = w = nfsacl_size(
190 			(resp->mask & NFS_ACL)   ? resp->acl_access  : NULL,
191 			(resp->mask & NFS_DFACL) ? resp->acl_default : NULL);
192 		while (w > 0) {
193 			if (!*(rqstp->rq_next_page++))
194 				return 0;
195 			w -= PAGE_SIZE;
196 		}
197 
198 		n = nfsacl_encode(&rqstp->rq_res, base, inode,
199 				  resp->acl_access,
200 				  resp->mask & NFS_ACL, 0);
201 		if (n > 0)
202 			n = nfsacl_encode(&rqstp->rq_res, base + n, inode,
203 					  resp->acl_default,
204 					  resp->mask & NFS_DFACL,
205 					  NFS_ACL_DEFAULT);
206 		if (n <= 0)
207 			return 0;
208 	} else
209 		if (!xdr_ressize_check(rqstp, p))
210 			return 0;
211 
212 	return 1;
213 }
214 
215 /* SETACL */
216 static int nfs3svc_encode_setaclres(struct svc_rqst *rqstp, __be32 *p)
217 {
218 	struct nfsd3_attrstat *resp = rqstp->rq_resp;
219 
220 	p = nfs3svc_encode_post_op_attr(rqstp, p, &resp->fh);
221 
222 	return xdr_ressize_check(rqstp, p);
223 }
224 
225 /*
226  * XDR release functions
227  */
228 static void nfs3svc_release_getacl(struct svc_rqst *rqstp)
229 {
230 	struct nfsd3_getaclres *resp = rqstp->rq_resp;
231 
232 	fh_put(&resp->fh);
233 	posix_acl_release(resp->acl_access);
234 	posix_acl_release(resp->acl_default);
235 }
236 
237 #define nfs3svc_decode_voidargs		NULL
238 #define nfs3svc_release_void		NULL
239 #define nfsd3_setaclres			nfsd3_attrstat
240 #define nfsd3_voidres			nfsd3_voidargs
241 struct nfsd3_voidargs { int dummy; };
242 
243 #define PROC(name, argt, rest, relt, cache, respsize)			\
244 {									\
245 	.pc_func	= nfsd3_proc_##name,				\
246 	.pc_decode	= nfs3svc_decode_##argt##args,			\
247 	.pc_encode	= nfs3svc_encode_##rest##res,			\
248 	.pc_release	= nfs3svc_release_##relt,			\
249 	.pc_argsize	= sizeof(struct nfsd3_##argt##args),		\
250 	.pc_ressize	= sizeof(struct nfsd3_##rest##res),		\
251 	.pc_cachetype	= cache,					\
252 	.pc_xdrressize	= respsize,					\
253 }
254 
255 #define ST 1		/* status*/
256 #define AT 21		/* attributes */
257 #define pAT (1+AT)	/* post attributes - conditional */
258 #define ACL (1+NFS_ACL_MAX_ENTRIES*3)  /* Access Control List */
259 
260 static const struct svc_procedure nfsd_acl_procedures3[] = {
261   PROC(null,	void,		void,		void,	  RC_NOCACHE, ST),
262   PROC(getacl,	getacl,		getacl,		getacl,	  RC_NOCACHE, ST+1+2*(1+ACL)),
263   PROC(setacl,	setacl,		setacl,		fhandle,  RC_NOCACHE, ST+pAT),
264 };
265 
266 static unsigned int nfsd_acl_count3[ARRAY_SIZE(nfsd_acl_procedures3)];
267 const struct svc_version nfsd_acl_version3 = {
268 	.vs_vers	= 3,
269 	.vs_nproc	= 3,
270 	.vs_proc	= nfsd_acl_procedures3,
271 	.vs_count	= nfsd_acl_count3,
272 	.vs_dispatch	= nfsd_dispatch,
273 	.vs_xdrsize	= NFS3_SVC_XDRSIZE,
274 };
275 
276