xref: /linux/fs/nfsd/nfs3acl.c (revision f3a8b6645dc2e60d11f20c1c23afd964ff4e55ae)
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 = d_inode(fh->fh_dentry);
43 
44 	if (argp->mask & ~NFS_ACL_MASK)
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 (acl == NULL) {
51 			/* Solaris returns the inode's minimum ACL. */
52 			acl = posix_acl_from_mode(inode->i_mode, GFP_KERNEL);
53 		}
54 		if (IS_ERR(acl)) {
55 			nfserr = nfserrno(PTR_ERR(acl));
56 			goto fail;
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 = d_inode(fh->fh_dentry);
98 
99 	error = fh_want_write(fh);
100 	if (error)
101 		goto out_errno;
102 
103 	fh_lock(fh);
104 
105 	error = set_posix_acl(inode, ACL_TYPE_ACCESS, argp->acl_access);
106 	if (error)
107 		goto out_drop_lock;
108 	error = set_posix_acl(inode, ACL_TYPE_DEFAULT, argp->acl_default);
109 
110 out_drop_lock:
111 	fh_unlock(fh);
112 	fh_drop_write(fh);
113 out_errno:
114 	nfserr = nfserrno(error);
115 out:
116 	/* argp->acl_{access,default} may have been allocated in
117 	   nfs3svc_decode_setaclargs. */
118 	posix_acl_release(argp->acl_access);
119 	posix_acl_release(argp->acl_default);
120 	RETURN_STATUS(nfserr);
121 }
122 
123 /*
124  * XDR decode functions
125  */
126 static int nfs3svc_decode_getaclargs(struct svc_rqst *rqstp, __be32 *p,
127 		struct nfsd3_getaclargs *args)
128 {
129 	p = nfs3svc_decode_fh(p, &args->fh);
130 	if (!p)
131 		return 0;
132 	args->mask = ntohl(*p); p++;
133 
134 	return xdr_argsize_check(rqstp, p);
135 }
136 
137 
138 static int nfs3svc_decode_setaclargs(struct svc_rqst *rqstp, __be32 *p,
139 		struct nfsd3_setaclargs *args)
140 {
141 	struct kvec *head = rqstp->rq_arg.head;
142 	unsigned int base;
143 	int n;
144 
145 	p = nfs3svc_decode_fh(p, &args->fh);
146 	if (!p)
147 		return 0;
148 	args->mask = ntohl(*p++);
149 	if (args->mask & ~NFS_ACL_MASK ||
150 	    !xdr_argsize_check(rqstp, p))
151 		return 0;
152 
153 	base = (char *)p - (char *)head->iov_base;
154 	n = nfsacl_decode(&rqstp->rq_arg, base, NULL,
155 			  (args->mask & NFS_ACL) ?
156 			  &args->acl_access : NULL);
157 	if (n > 0)
158 		n = nfsacl_decode(&rqstp->rq_arg, base + n, NULL,
159 				  (args->mask & NFS_DFACL) ?
160 				  &args->acl_default : NULL);
161 	return (n > 0);
162 }
163 
164 /*
165  * XDR encode functions
166  */
167 
168 /* GETACL */
169 static int nfs3svc_encode_getaclres(struct svc_rqst *rqstp, __be32 *p,
170 		struct nfsd3_getaclres *resp)
171 {
172 	struct dentry *dentry = resp->fh.fh_dentry;
173 
174 	p = nfs3svc_encode_post_op_attr(rqstp, p, &resp->fh);
175 	if (resp->status == 0 && dentry && d_really_is_positive(dentry)) {
176 		struct inode *inode = d_inode(dentry);
177 		struct kvec *head = rqstp->rq_res.head;
178 		unsigned int base;
179 		int n;
180 		int w;
181 
182 		*p++ = htonl(resp->mask);
183 		if (!xdr_ressize_check(rqstp, p))
184 			return 0;
185 		base = (char *)p - (char *)head->iov_base;
186 
187 		rqstp->rq_res.page_len = w = nfsacl_size(
188 			(resp->mask & NFS_ACL)   ? resp->acl_access  : NULL,
189 			(resp->mask & NFS_DFACL) ? resp->acl_default : NULL);
190 		while (w > 0) {
191 			if (!*(rqstp->rq_next_page++))
192 				return 0;
193 			w -= PAGE_SIZE;
194 		}
195 
196 		n = nfsacl_encode(&rqstp->rq_res, base, inode,
197 				  resp->acl_access,
198 				  resp->mask & NFS_ACL, 0);
199 		if (n > 0)
200 			n = nfsacl_encode(&rqstp->rq_res, base + n, inode,
201 					  resp->acl_default,
202 					  resp->mask & NFS_DFACL,
203 					  NFS_ACL_DEFAULT);
204 		if (n <= 0)
205 			return 0;
206 	} else
207 		if (!xdr_ressize_check(rqstp, p))
208 			return 0;
209 
210 	return 1;
211 }
212 
213 /* SETACL */
214 static int nfs3svc_encode_setaclres(struct svc_rqst *rqstp, __be32 *p,
215 		struct nfsd3_attrstat *resp)
216 {
217 	p = nfs3svc_encode_post_op_attr(rqstp, p, &resp->fh);
218 
219 	return xdr_ressize_check(rqstp, p);
220 }
221 
222 /*
223  * XDR release functions
224  */
225 static int nfs3svc_release_getacl(struct svc_rqst *rqstp, __be32 *p,
226 		struct nfsd3_getaclres *resp)
227 {
228 	fh_put(&resp->fh);
229 	posix_acl_release(resp->acl_access);
230 	posix_acl_release(resp->acl_default);
231 	return 1;
232 }
233 
234 #define nfs3svc_decode_voidargs		NULL
235 #define nfs3svc_release_void		NULL
236 #define nfsd3_setaclres			nfsd3_attrstat
237 #define nfsd3_voidres			nfsd3_voidargs
238 struct nfsd3_voidargs { int dummy; };
239 
240 #define PROC(name, argt, rest, relt, cache, respsize)	\
241  { (svc_procfunc) nfsd3_proc_##name,		\
242    (kxdrproc_t) nfs3svc_decode_##argt##args,	\
243    (kxdrproc_t) nfs3svc_encode_##rest##res,	\
244    (kxdrproc_t) nfs3svc_release_##relt,		\
245    sizeof(struct nfsd3_##argt##args),		\
246    sizeof(struct nfsd3_##rest##res),		\
247    0,						\
248    cache,					\
249    respsize,					\
250  }
251 
252 #define ST 1		/* status*/
253 #define AT 21		/* attributes */
254 #define pAT (1+AT)	/* post attributes - conditional */
255 #define ACL (1+NFS_ACL_MAX_ENTRIES*3)  /* Access Control List */
256 
257 static struct svc_procedure		nfsd_acl_procedures3[] = {
258   PROC(null,	void,		void,		void,	  RC_NOCACHE, ST),
259   PROC(getacl,	getacl,		getacl,		getacl,	  RC_NOCACHE, ST+1+2*(1+ACL)),
260   PROC(setacl,	setacl,		setacl,		fhandle,  RC_NOCACHE, ST+pAT),
261 };
262 
263 struct svc_version	nfsd_acl_version3 = {
264 		.vs_vers	= 3,
265 		.vs_nproc	= 3,
266 		.vs_proc	= nfsd_acl_procedures3,
267 		.vs_dispatch	= nfsd_dispatch,
268 		.vs_xdrsize	= NFS3_SVC_XDRSIZE,
269 		.vs_hidden	= 0,
270 };
271 
272