1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * linux/fs/lockd/xdr4.c
4 *
5 * XDR support for lockd and the lock client.
6 *
7 * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
8 * Copyright (C) 1999, Trond Myklebust <trond.myklebust@fys.uio.no>
9 */
10
11 #include <linux/types.h>
12 #include <linux/sched.h>
13 #include <linux/nfs.h>
14
15 #include <linux/sunrpc/xdr.h>
16 #include <linux/sunrpc/clnt.h>
17 #include <linux/sunrpc/svc.h>
18 #include <linux/sunrpc/stats.h>
19 #include <linux/lockd/lockd.h>
20
21 #include "svcxdr.h"
22
23 static inline s64
loff_t_to_s64(loff_t offset)24 loff_t_to_s64(loff_t offset)
25 {
26 s64 res;
27 if (offset > NLM4_OFFSET_MAX)
28 res = NLM4_OFFSET_MAX;
29 else if (offset < -NLM4_OFFSET_MAX)
30 res = -NLM4_OFFSET_MAX;
31 else
32 res = offset;
33 return res;
34 }
35
36 /*
37 * NLM file handles are defined by specification to be a variable-length
38 * XDR opaque no longer than 1024 bytes. However, this implementation
39 * limits their length to the size of an NFSv3 file handle.
40 */
41 static bool
svcxdr_decode_fhandle(struct xdr_stream * xdr,struct nfs_fh * fh)42 svcxdr_decode_fhandle(struct xdr_stream *xdr, struct nfs_fh *fh)
43 {
44 __be32 *p;
45 u32 len;
46
47 if (xdr_stream_decode_u32(xdr, &len) < 0)
48 return false;
49 if (len > NFS_MAXFHSIZE)
50 return false;
51
52 p = xdr_inline_decode(xdr, len);
53 if (!p)
54 return false;
55 fh->size = len;
56 memcpy(fh->data, p, len);
57 memset(fh->data + len, 0, sizeof(fh->data) - len);
58
59 return true;
60 }
61
62 static bool
svcxdr_decode_lock(struct xdr_stream * xdr,struct nlm_lock * lock)63 svcxdr_decode_lock(struct xdr_stream *xdr, struct nlm_lock *lock)
64 {
65 struct file_lock *fl = &lock->fl;
66
67 if (!svcxdr_decode_string(xdr, &lock->caller, &lock->len))
68 return false;
69 if (!svcxdr_decode_fhandle(xdr, &lock->fh))
70 return false;
71 if (!svcxdr_decode_owner(xdr, &lock->oh))
72 return false;
73 if (xdr_stream_decode_u32(xdr, &lock->svid) < 0)
74 return false;
75 if (xdr_stream_decode_u64(xdr, &lock->lock_start) < 0)
76 return false;
77 if (xdr_stream_decode_u64(xdr, &lock->lock_len) < 0)
78 return false;
79
80 locks_init_lock(fl);
81 fl->fl_flags = FL_POSIX;
82 fl->fl_type = F_RDLCK;
83
84 return true;
85 }
86
87 static bool
svcxdr_encode_holder(struct xdr_stream * xdr,const struct nlm_lock * lock)88 svcxdr_encode_holder(struct xdr_stream *xdr, const struct nlm_lock *lock)
89 {
90 const struct file_lock *fl = &lock->fl;
91 s64 start, len;
92
93 /* exclusive */
94 if (xdr_stream_encode_bool(xdr, fl->fl_type != F_RDLCK) < 0)
95 return false;
96 if (xdr_stream_encode_u32(xdr, lock->svid) < 0)
97 return false;
98 if (!svcxdr_encode_owner(xdr, &lock->oh))
99 return false;
100 start = loff_t_to_s64(fl->fl_start);
101 if (fl->fl_end == OFFSET_MAX)
102 len = 0;
103 else
104 len = loff_t_to_s64(fl->fl_end - fl->fl_start + 1);
105 if (xdr_stream_encode_u64(xdr, start) < 0)
106 return false;
107 if (xdr_stream_encode_u64(xdr, len) < 0)
108 return false;
109
110 return true;
111 }
112
113 static bool
svcxdr_encode_testrply(struct xdr_stream * xdr,const struct nlm_res * resp)114 svcxdr_encode_testrply(struct xdr_stream *xdr, const struct nlm_res *resp)
115 {
116 if (!svcxdr_encode_stats(xdr, resp->status))
117 return false;
118 switch (resp->status) {
119 case nlm_lck_denied:
120 if (!svcxdr_encode_holder(xdr, &resp->lock))
121 return false;
122 }
123
124 return true;
125 }
126
127
128 /*
129 * Decode Call arguments
130 */
131
132 bool
nlm4svc_decode_void(struct svc_rqst * rqstp,struct xdr_stream * xdr)133 nlm4svc_decode_void(struct svc_rqst *rqstp, struct xdr_stream *xdr)
134 {
135 return true;
136 }
137
138 bool
nlm4svc_decode_testargs(struct svc_rqst * rqstp,struct xdr_stream * xdr)139 nlm4svc_decode_testargs(struct svc_rqst *rqstp, struct xdr_stream *xdr)
140 {
141 struct nlm_args *argp = rqstp->rq_argp;
142 u32 exclusive;
143
144 if (!svcxdr_decode_cookie(xdr, &argp->cookie))
145 return false;
146 if (xdr_stream_decode_bool(xdr, &exclusive) < 0)
147 return false;
148 if (!svcxdr_decode_lock(xdr, &argp->lock))
149 return false;
150 if (exclusive)
151 argp->lock.fl.fl_type = F_WRLCK;
152
153 return true;
154 }
155
156 bool
nlm4svc_decode_lockargs(struct svc_rqst * rqstp,struct xdr_stream * xdr)157 nlm4svc_decode_lockargs(struct svc_rqst *rqstp, struct xdr_stream *xdr)
158 {
159 struct nlm_args *argp = rqstp->rq_argp;
160 u32 exclusive;
161
162 if (!svcxdr_decode_cookie(xdr, &argp->cookie))
163 return false;
164 if (xdr_stream_decode_bool(xdr, &argp->block) < 0)
165 return false;
166 if (xdr_stream_decode_bool(xdr, &exclusive) < 0)
167 return false;
168 if (!svcxdr_decode_lock(xdr, &argp->lock))
169 return false;
170 if (exclusive)
171 argp->lock.fl.fl_type = F_WRLCK;
172 if (xdr_stream_decode_bool(xdr, &argp->reclaim) < 0)
173 return false;
174 if (xdr_stream_decode_u32(xdr, &argp->state) < 0)
175 return false;
176 argp->monitor = 1; /* monitor client by default */
177
178 return true;
179 }
180
181 bool
nlm4svc_decode_cancargs(struct svc_rqst * rqstp,struct xdr_stream * xdr)182 nlm4svc_decode_cancargs(struct svc_rqst *rqstp, struct xdr_stream *xdr)
183 {
184 struct nlm_args *argp = rqstp->rq_argp;
185 u32 exclusive;
186
187 if (!svcxdr_decode_cookie(xdr, &argp->cookie))
188 return false;
189 if (xdr_stream_decode_bool(xdr, &argp->block) < 0)
190 return false;
191 if (xdr_stream_decode_bool(xdr, &exclusive) < 0)
192 return false;
193 if (!svcxdr_decode_lock(xdr, &argp->lock))
194 return false;
195 if (exclusive)
196 argp->lock.fl.fl_type = F_WRLCK;
197
198 return true;
199 }
200
201 bool
nlm4svc_decode_unlockargs(struct svc_rqst * rqstp,struct xdr_stream * xdr)202 nlm4svc_decode_unlockargs(struct svc_rqst *rqstp, struct xdr_stream *xdr)
203 {
204 struct nlm_args *argp = rqstp->rq_argp;
205
206 if (!svcxdr_decode_cookie(xdr, &argp->cookie))
207 return false;
208 if (!svcxdr_decode_lock(xdr, &argp->lock))
209 return false;
210 argp->lock.fl.fl_type = F_UNLCK;
211
212 return true;
213 }
214
215 bool
nlm4svc_decode_res(struct svc_rqst * rqstp,struct xdr_stream * xdr)216 nlm4svc_decode_res(struct svc_rqst *rqstp, struct xdr_stream *xdr)
217 {
218 struct nlm_res *resp = rqstp->rq_argp;
219
220 if (!svcxdr_decode_cookie(xdr, &resp->cookie))
221 return false;
222 if (!svcxdr_decode_stats(xdr, &resp->status))
223 return false;
224
225 return true;
226 }
227
228 bool
nlm4svc_decode_reboot(struct svc_rqst * rqstp,struct xdr_stream * xdr)229 nlm4svc_decode_reboot(struct svc_rqst *rqstp, struct xdr_stream *xdr)
230 {
231 struct nlm_reboot *argp = rqstp->rq_argp;
232 __be32 *p;
233 u32 len;
234
235 if (xdr_stream_decode_u32(xdr, &len) < 0)
236 return false;
237 if (len > SM_MAXSTRLEN)
238 return false;
239 p = xdr_inline_decode(xdr, len);
240 if (!p)
241 return false;
242 argp->len = len;
243 argp->mon = (char *)p;
244 if (xdr_stream_decode_u32(xdr, &argp->state) < 0)
245 return false;
246 p = xdr_inline_decode(xdr, SM_PRIV_SIZE);
247 if (!p)
248 return false;
249 memcpy(&argp->priv.data, p, sizeof(argp->priv.data));
250
251 return true;
252 }
253
254 bool
nlm4svc_decode_shareargs(struct svc_rqst * rqstp,struct xdr_stream * xdr)255 nlm4svc_decode_shareargs(struct svc_rqst *rqstp, struct xdr_stream *xdr)
256 {
257 struct nlm_args *argp = rqstp->rq_argp;
258 struct nlm_lock *lock = &argp->lock;
259
260 memset(lock, 0, sizeof(*lock));
261 locks_init_lock(&lock->fl);
262 lock->svid = ~(u32)0;
263
264 if (!svcxdr_decode_cookie(xdr, &argp->cookie))
265 return false;
266 if (!svcxdr_decode_string(xdr, &lock->caller, &lock->len))
267 return false;
268 if (!svcxdr_decode_fhandle(xdr, &lock->fh))
269 return false;
270 if (!svcxdr_decode_owner(xdr, &lock->oh))
271 return false;
272 /* XXX: Range checks are missing in the original code */
273 if (xdr_stream_decode_u32(xdr, &argp->fsm_mode) < 0)
274 return false;
275 if (xdr_stream_decode_u32(xdr, &argp->fsm_access) < 0)
276 return false;
277
278 return true;
279 }
280
281 bool
nlm4svc_decode_notify(struct svc_rqst * rqstp,struct xdr_stream * xdr)282 nlm4svc_decode_notify(struct svc_rqst *rqstp, struct xdr_stream *xdr)
283 {
284 struct nlm_args *argp = rqstp->rq_argp;
285 struct nlm_lock *lock = &argp->lock;
286
287 if (!svcxdr_decode_string(xdr, &lock->caller, &lock->len))
288 return false;
289 if (xdr_stream_decode_u32(xdr, &argp->state) < 0)
290 return false;
291
292 return true;
293 }
294
295
296 /*
297 * Encode Reply results
298 */
299
300 bool
nlm4svc_encode_void(struct svc_rqst * rqstp,struct xdr_stream * xdr)301 nlm4svc_encode_void(struct svc_rqst *rqstp, struct xdr_stream *xdr)
302 {
303 return true;
304 }
305
306 bool
nlm4svc_encode_testres(struct svc_rqst * rqstp,struct xdr_stream * xdr)307 nlm4svc_encode_testres(struct svc_rqst *rqstp, struct xdr_stream *xdr)
308 {
309 struct nlm_res *resp = rqstp->rq_resp;
310
311 return svcxdr_encode_cookie(xdr, &resp->cookie) &&
312 svcxdr_encode_testrply(xdr, resp);
313 }
314
315 bool
nlm4svc_encode_res(struct svc_rqst * rqstp,struct xdr_stream * xdr)316 nlm4svc_encode_res(struct svc_rqst *rqstp, struct xdr_stream *xdr)
317 {
318 struct nlm_res *resp = rqstp->rq_resp;
319
320 return svcxdr_encode_cookie(xdr, &resp->cookie) &&
321 svcxdr_encode_stats(xdr, resp->status);
322 }
323
324 bool
nlm4svc_encode_shareres(struct svc_rqst * rqstp,struct xdr_stream * xdr)325 nlm4svc_encode_shareres(struct svc_rqst *rqstp, struct xdr_stream *xdr)
326 {
327 struct nlm_res *resp = rqstp->rq_resp;
328
329 if (!svcxdr_encode_cookie(xdr, &resp->cookie))
330 return false;
331 if (!svcxdr_encode_stats(xdr, resp->status))
332 return false;
333 /* sequence */
334 if (xdr_stream_encode_u32(xdr, 0) < 0)
335 return false;
336
337 return true;
338 }
339