xref: /linux/fs/nfsd/nfs3acl.c (revision c5aec4c76af1a2d89ee2f2d4d5463b2ad2d85de5)
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, void *argp, void *resp)
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 		struct nfsd3_getaclargs *argp, struct nfsd3_getaclres *resp)
31 {
32 	struct posix_acl *acl;
33 	struct inode *inode;
34 	svc_fh *fh;
35 	__be32 nfserr = 0;
36 
37 	fh = fh_copy(&resp->fh, &argp->fh);
38 	nfserr = fh_verify(rqstp, &resp->fh, 0, NFSD_MAY_NOP);
39 	if (nfserr)
40 		RETURN_STATUS(nfserr);
41 
42 	inode = fh->fh_dentry->d_inode;
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 = get_acl(inode, ACL_TYPE_ACCESS);
50 		if (IS_ERR(acl)) {
51 			nfserr = nfserrno(PTR_ERR(acl));
52 			goto fail;
53 		}
54 		if (acl == NULL) {
55 			/* Solaris returns the inode's minimum ACL. */
56 			acl = posix_acl_from_mode(inode->i_mode, GFP_KERNEL);
57 		}
58 		resp->acl_access = acl;
59 	}
60 	if (resp->mask & (NFS_DFACL|NFS_DFACLCNT)) {
61 		/* Check how Solaris handles requests for the Default ACL
62 		   of a non-directory! */
63 		acl = get_acl(inode, ACL_TYPE_DEFAULT);
64 		if (IS_ERR(acl)) {
65 			nfserr = nfserrno(PTR_ERR(acl));
66 			goto fail;
67 		}
68 		resp->acl_default = acl;
69 	}
70 
71 	/* resp->acl_{access,default} are released in nfs3svc_release_getacl. */
72 	RETURN_STATUS(0);
73 
74 fail:
75 	posix_acl_release(resp->acl_access);
76 	posix_acl_release(resp->acl_default);
77 	RETURN_STATUS(nfserr);
78 }
79 
80 /*
81  * Set the Access and/or Default ACL of a file.
82  */
83 static __be32 nfsd3_proc_setacl(struct svc_rqst * rqstp,
84 		struct nfsd3_setaclargs *argp,
85 		struct nfsd3_attrstat *resp)
86 {
87 	struct inode *inode;
88 	svc_fh *fh;
89 	__be32 nfserr = 0;
90 	int error;
91 
92 	fh = fh_copy(&resp->fh, &argp->fh);
93 	nfserr = fh_verify(rqstp, &resp->fh, 0, NFSD_MAY_SATTR);
94 	if (nfserr)
95 		goto out;
96 
97 	inode = fh->fh_dentry->d_inode;
98 	if (!IS_POSIXACL(inode) || !inode->i_op->set_acl) {
99 		error = -EOPNOTSUPP;
100 		goto out_errno;
101 	}
102 
103 	error = fh_want_write(fh);
104 	if (error)
105 		goto out_errno;
106 
107 	error = inode->i_op->set_acl(inode, argp->acl_access, ACL_TYPE_ACCESS);
108 	if (error)
109 		goto out_drop_write;
110 	error = inode->i_op->set_acl(inode, argp->acl_default,
111 				     ACL_TYPE_DEFAULT);
112 
113 out_drop_write:
114 	fh_drop_write(fh);
115 out_errno:
116 	nfserr = nfserrno(error);
117 out:
118 	/* argp->acl_{access,default} may have been allocated in
119 	   nfs3svc_decode_setaclargs. */
120 	posix_acl_release(argp->acl_access);
121 	posix_acl_release(argp->acl_default);
122 	RETURN_STATUS(nfserr);
123 }
124 
125 /*
126  * XDR decode functions
127  */
128 static int nfs3svc_decode_getaclargs(struct svc_rqst *rqstp, __be32 *p,
129 		struct nfsd3_getaclargs *args)
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 		struct nfsd3_setaclargs *args)
142 {
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|NFS_ACLCNT|NFS_DFACL|NFS_DFACLCNT) ||
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 		struct nfsd3_getaclres *resp)
173 {
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 && dentry->d_inode) {
178 		struct inode *inode = dentry->d_inode;
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 		struct nfsd3_attrstat *resp)
218 {
219 	p = nfs3svc_encode_post_op_attr(rqstp, p, &resp->fh);
220 
221 	return xdr_ressize_check(rqstp, p);
222 }
223 
224 /*
225  * XDR release functions
226  */
227 static int nfs3svc_release_getacl(struct svc_rqst *rqstp, __be32 *p,
228 		struct nfsd3_getaclres *resp)
229 {
230 	fh_put(&resp->fh);
231 	posix_acl_release(resp->acl_access);
232 	posix_acl_release(resp->acl_default);
233 	return 1;
234 }
235 
236 #define nfs3svc_decode_voidargs		NULL
237 #define nfs3svc_release_void		NULL
238 #define nfsd3_setaclres			nfsd3_attrstat
239 #define nfsd3_voidres			nfsd3_voidargs
240 struct nfsd3_voidargs { int dummy; };
241 
242 #define PROC(name, argt, rest, relt, cache, respsize)	\
243  { (svc_procfunc) nfsd3_proc_##name,		\
244    (kxdrproc_t) nfs3svc_decode_##argt##args,	\
245    (kxdrproc_t) nfs3svc_encode_##rest##res,	\
246    (kxdrproc_t) nfs3svc_release_##relt,		\
247    sizeof(struct nfsd3_##argt##args),		\
248    sizeof(struct nfsd3_##rest##res),		\
249    0,						\
250    cache,					\
251    respsize,					\
252  }
253 
254 #define ST 1		/* status*/
255 #define AT 21		/* attributes */
256 #define pAT (1+AT)	/* post attributes - conditional */
257 #define ACL (1+NFS_ACL_MAX_ENTRIES*3)  /* Access Control List */
258 
259 static struct svc_procedure		nfsd_acl_procedures3[] = {
260   PROC(null,	void,		void,		void,	  RC_NOCACHE, ST),
261   PROC(getacl,	getacl,		getacl,		getacl,	  RC_NOCACHE, ST+1+2*(1+ACL)),
262   PROC(setacl,	setacl,		setacl,		fhandle,  RC_NOCACHE, ST+pAT),
263 };
264 
265 struct svc_version	nfsd_acl_version3 = {
266 		.vs_vers	= 3,
267 		.vs_nproc	= 3,
268 		.vs_proc	= nfsd_acl_procedures3,
269 		.vs_dispatch	= nfsd_dispatch,
270 		.vs_xdrsize	= NFS3_SVC_XDRSIZE,
271 		.vs_hidden	= 0,
272 };
273 
274