1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Process version 3 NFSACL requests.
4  *
5  * Copyright (C) 2002-2003 Andreas Gruenbacher <agruen@suse.de>
6  */
7 
8 #include "nfsd.h"
9 /* FIXME: nfsacl.h is a broken header */
10 #include <linux/nfsacl.h>
11 #include <linux/gfp.h>
12 #include "cache.h"
13 #include "xdr3.h"
14 #include "vfs.h"
15 
16 /*
17  * NULL call.
18  */
19 static __be32
nfsd3_proc_null(struct svc_rqst * rqstp)20 nfsd3_proc_null(struct svc_rqst *rqstp)
21 {
22 	return rpc_success;
23 }
24 
25 /*
26  * Get the Access and/or Default ACL of a file.
27  */
nfsd3_proc_getacl(struct svc_rqst * rqstp)28 static __be32 nfsd3_proc_getacl(struct svc_rqst *rqstp)
29 {
30 	struct nfsd3_getaclargs *argp = rqstp->rq_argp;
31 	struct nfsd3_getaclres *resp = rqstp->rq_resp;
32 	struct posix_acl *acl;
33 	struct inode *inode;
34 	svc_fh *fh;
35 
36 	fh = fh_copy(&resp->fh, &argp->fh);
37 	resp->status = fh_verify(rqstp, &resp->fh, 0, NFSD_MAY_NOP);
38 	if (resp->status != nfs_ok)
39 		goto out;
40 
41 	inode = d_inode(fh->fh_dentry);
42 
43 	if (argp->mask & ~NFS_ACL_MASK) {
44 		resp->status = nfserr_inval;
45 		goto out;
46 	}
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 			resp->status = 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 			resp->status = 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 out:
74 	return rpc_success;
75 
76 fail:
77 	posix_acl_release(resp->acl_access);
78 	posix_acl_release(resp->acl_default);
79 	goto out;
80 }
81 
82 /*
83  * Set the Access and/or Default ACL of a file.
84  */
nfsd3_proc_setacl(struct svc_rqst * rqstp)85 static __be32 nfsd3_proc_setacl(struct svc_rqst *rqstp)
86 {
87 	struct nfsd3_setaclargs *argp = rqstp->rq_argp;
88 	struct nfsd3_attrstat *resp = rqstp->rq_resp;
89 	struct inode *inode;
90 	svc_fh *fh;
91 	int error;
92 
93 	fh = fh_copy(&resp->fh, &argp->fh);
94 	resp->status = fh_verify(rqstp, &resp->fh, 0, NFSD_MAY_SATTR);
95 	if (resp->status != nfs_ok)
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(&init_user_ns, inode, ACL_TYPE_ACCESS,
107 			      argp->acl_access);
108 	if (error)
109 		goto out_drop_lock;
110 	error = set_posix_acl(&init_user_ns, inode, ACL_TYPE_DEFAULT,
111 			      argp->acl_default);
112 
113 out_drop_lock:
114 	fh_unlock(fh);
115 	fh_drop_write(fh);
116 out_errno:
117 	resp->status = nfserrno(error);
118 out:
119 	/* argp->acl_{access,default} may have been allocated in
120 	   nfs3svc_decode_setaclargs. */
121 	posix_acl_release(argp->acl_access);
122 	posix_acl_release(argp->acl_default);
123 	return rpc_success;
124 }
125 
126 /*
127  * XDR decode functions
128  */
129 
130 static bool
nfs3svc_decode_getaclargs(struct svc_rqst * rqstp,struct xdr_stream * xdr)131 nfs3svc_decode_getaclargs(struct svc_rqst *rqstp, struct xdr_stream *xdr)
132 {
133 	struct nfsd3_getaclargs *args = rqstp->rq_argp;
134 
135 	if (!svcxdr_decode_nfs_fh3(xdr, &args->fh))
136 		return false;
137 	if (xdr_stream_decode_u32(xdr, &args->mask) < 0)
138 		return false;
139 
140 	return true;
141 }
142 
143 static bool
nfs3svc_decode_setaclargs(struct svc_rqst * rqstp,struct xdr_stream * xdr)144 nfs3svc_decode_setaclargs(struct svc_rqst *rqstp, struct xdr_stream *xdr)
145 {
146 	struct nfsd3_setaclargs *argp = rqstp->rq_argp;
147 
148 	if (!svcxdr_decode_nfs_fh3(xdr, &argp->fh))
149 		return false;
150 	if (xdr_stream_decode_u32(xdr, &argp->mask) < 0)
151 		return false;
152 	if (argp->mask & ~NFS_ACL_MASK)
153 		return false;
154 	if (!nfs_stream_decode_acl(xdr, NULL, (argp->mask & NFS_ACL) ?
155 				   &argp->acl_access : NULL))
156 		return false;
157 	if (!nfs_stream_decode_acl(xdr, NULL, (argp->mask & NFS_DFACL) ?
158 				   &argp->acl_default : NULL))
159 		return false;
160 
161 	return true;
162 }
163 
164 /*
165  * XDR encode functions
166  */
167 
168 /* GETACL */
169 static bool
nfs3svc_encode_getaclres(struct svc_rqst * rqstp,struct xdr_stream * xdr)170 nfs3svc_encode_getaclres(struct svc_rqst *rqstp, struct xdr_stream *xdr)
171 {
172 	struct nfsd3_getaclres *resp = rqstp->rq_resp;
173 	struct dentry *dentry = resp->fh.fh_dentry;
174 	struct kvec *head = rqstp->rq_res.head;
175 	struct inode *inode;
176 	unsigned int base;
177 	int n;
178 	int w;
179 
180 	if (!svcxdr_encode_nfsstat3(xdr, resp->status))
181 		return false;
182 	switch (resp->status) {
183 	case nfs_ok:
184 		inode = d_inode(dentry);
185 		if (!svcxdr_encode_post_op_attr(rqstp, xdr, &resp->fh))
186 			return false;
187 		if (xdr_stream_encode_u32(xdr, resp->mask) < 0)
188 			return false;
189 
190 		base = (char *)xdr->p - (char *)head->iov_base;
191 
192 		rqstp->rq_res.page_len = w = nfsacl_size(
193 			(resp->mask & NFS_ACL)   ? resp->acl_access  : NULL,
194 			(resp->mask & NFS_DFACL) ? resp->acl_default : NULL);
195 		while (w > 0) {
196 			if (!*(rqstp->rq_next_page++))
197 				return false;
198 			w -= PAGE_SIZE;
199 		}
200 
201 		n = nfsacl_encode(&rqstp->rq_res, base, inode,
202 				  resp->acl_access,
203 				  resp->mask & NFS_ACL, 0);
204 		if (n > 0)
205 			n = nfsacl_encode(&rqstp->rq_res, base + n, inode,
206 					  resp->acl_default,
207 					  resp->mask & NFS_DFACL,
208 					  NFS_ACL_DEFAULT);
209 		if (n <= 0)
210 			return false;
211 		break;
212 	default:
213 		if (!svcxdr_encode_post_op_attr(rqstp, xdr, &resp->fh))
214 			return false;
215 	}
216 
217 	return true;
218 }
219 
220 /* SETACL */
221 static bool
nfs3svc_encode_setaclres(struct svc_rqst * rqstp,struct xdr_stream * xdr)222 nfs3svc_encode_setaclres(struct svc_rqst *rqstp, struct xdr_stream *xdr)
223 {
224 	struct nfsd3_attrstat *resp = rqstp->rq_resp;
225 
226 	return svcxdr_encode_nfsstat3(xdr, resp->status) &&
227 		svcxdr_encode_post_op_attr(rqstp, xdr, &resp->fh);
228 }
229 
230 /*
231  * XDR release functions
232  */
nfs3svc_release_getacl(struct svc_rqst * rqstp)233 static void nfs3svc_release_getacl(struct svc_rqst *rqstp)
234 {
235 	struct nfsd3_getaclres *resp = rqstp->rq_resp;
236 
237 	fh_put(&resp->fh);
238 	posix_acl_release(resp->acl_access);
239 	posix_acl_release(resp->acl_default);
240 }
241 
242 struct nfsd3_voidargs { int dummy; };
243 
244 #define ST 1		/* status*/
245 #define AT 21		/* attributes */
246 #define pAT (1+AT)	/* post attributes - conditional */
247 #define ACL (1+NFS_ACL_MAX_ENTRIES*3)  /* Access Control List */
248 
249 static const struct svc_procedure nfsd_acl_procedures3[3] = {
250 	[ACLPROC3_NULL] = {
251 		.pc_func = nfsd3_proc_null,
252 		.pc_decode = nfssvc_decode_voidarg,
253 		.pc_encode = nfssvc_encode_voidres,
254 		.pc_argsize = sizeof(struct nfsd_voidargs),
255 		.pc_ressize = sizeof(struct nfsd_voidres),
256 		.pc_cachetype = RC_NOCACHE,
257 		.pc_xdrressize = ST,
258 		.pc_name = "NULL",
259 	},
260 	[ACLPROC3_GETACL] = {
261 		.pc_func = nfsd3_proc_getacl,
262 		.pc_decode = nfs3svc_decode_getaclargs,
263 		.pc_encode = nfs3svc_encode_getaclres,
264 		.pc_release = nfs3svc_release_getacl,
265 		.pc_argsize = sizeof(struct nfsd3_getaclargs),
266 		.pc_ressize = sizeof(struct nfsd3_getaclres),
267 		.pc_cachetype = RC_NOCACHE,
268 		.pc_xdrressize = ST+1+2*(1+ACL),
269 		.pc_name = "GETACL",
270 	},
271 	[ACLPROC3_SETACL] = {
272 		.pc_func = nfsd3_proc_setacl,
273 		.pc_decode = nfs3svc_decode_setaclargs,
274 		.pc_encode = nfs3svc_encode_setaclres,
275 		.pc_release = nfs3svc_release_fhandle,
276 		.pc_argsize = sizeof(struct nfsd3_setaclargs),
277 		.pc_ressize = sizeof(struct nfsd3_attrstat),
278 		.pc_cachetype = RC_NOCACHE,
279 		.pc_xdrressize = ST+pAT,
280 		.pc_name = "SETACL",
281 	},
282 };
283 
284 static unsigned int nfsd_acl_count3[ARRAY_SIZE(nfsd_acl_procedures3)];
285 const struct svc_version nfsd_acl_version3 = {
286 	.vs_vers	= 3,
287 	.vs_nproc	= 3,
288 	.vs_proc	= nfsd_acl_procedures3,
289 	.vs_count	= nfsd_acl_count3,
290 	.vs_dispatch	= nfsd_dispatch,
291 	.vs_xdrsize	= NFS3_SVC_XDRSIZE,
292 };
293 
294