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
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 void nlm4svc_set_file_lock_range(struct file_lock *fl, u64 off, u64 len)
37 {
38 s64 end = off + len - 1;
39
40 fl->fl_start = off;
41 if (len == 0 || end < 0)
42 fl->fl_end = OFFSET_MAX;
43 else
44 fl->fl_end = end;
45 }
46
47 /*
48 * NLM file handles are defined by specification to be a variable-length
49 * XDR opaque no longer than 1024 bytes. However, this implementation
50 * limits their length to the size of an NFSv3 file handle.
51 */
52 static bool
53 svcxdr_decode_fhandle(struct xdr_stream *xdr, struct nfs_fh *fh)
54 {
55 __be32 *p;
56 u32 len;
57
58 if (xdr_stream_decode_u32(xdr, &len) < 0)
59 return false;
60 if (len > NFS_MAXFHSIZE)
61 return false;
62
63 p = xdr_inline_decode(xdr, len);
64 if (!p)
65 return false;
66 fh->size = len;
67 memcpy(fh->data, p, len);
68 memset(fh->data + len, 0, sizeof(fh->data) - len);
69
70 return true;
71 }
72
73 static bool
74 svcxdr_decode_lock(struct xdr_stream *xdr, struct nlm_lock *lock)
75 {
76 struct file_lock *fl = &lock->fl;
77
78 if (!svcxdr_decode_string(xdr, &lock->caller, &lock->len))
79 return false;
80 if (!svcxdr_decode_fhandle(xdr, &lock->fh))
81 return false;
82 if (!svcxdr_decode_owner(xdr, &lock->oh))
83 return false;
84 if (xdr_stream_decode_u32(xdr, &lock->svid) < 0)
85 return false;
86 if (xdr_stream_decode_u64(xdr, &lock->lock_start) < 0)
87 return false;
88 if (xdr_stream_decode_u64(xdr, &lock->lock_len) < 0)
89 return false;
90
91 locks_init_lock(fl);
92 fl->c.flc_flags = FL_POSIX;
93 fl->c.flc_type = F_RDLCK;
94 nlm4svc_set_file_lock_range(fl, lock->lock_start, lock->lock_len);
95 return true;
96 }
97
98 static bool
99 svcxdr_encode_holder(struct xdr_stream *xdr, const struct nlm_lock *lock)
100 {
101 const struct file_lock *fl = &lock->fl;
102 s64 start, len;
103
104 /* exclusive */
105 if (xdr_stream_encode_bool(xdr, fl->c.flc_type != F_RDLCK) < 0)
106 return false;
107 if (xdr_stream_encode_u32(xdr, lock->svid) < 0)
108 return false;
109 if (!svcxdr_encode_owner(xdr, &lock->oh))
110 return false;
111 start = loff_t_to_s64(fl->fl_start);
112 if (fl->fl_end == OFFSET_MAX)
113 len = 0;
114 else
115 len = loff_t_to_s64(fl->fl_end - fl->fl_start + 1);
116 if (xdr_stream_encode_u64(xdr, start) < 0)
117 return false;
118 if (xdr_stream_encode_u64(xdr, len) < 0)
119 return false;
120
121 return true;
122 }
123
124 static bool
125 svcxdr_encode_testrply(struct xdr_stream *xdr, const struct nlm_res *resp)
126 {
127 if (!svcxdr_encode_stats(xdr, resp->status))
128 return false;
129 switch (resp->status) {
130 case nlm_lck_denied:
131 if (!svcxdr_encode_holder(xdr, &resp->lock))
132 return false;
133 }
134
135 return true;
136 }
137
138
139 /*
140 * Decode Call arguments
141 */
142
143 bool
144 nlm4svc_decode_void(struct svc_rqst *rqstp, struct xdr_stream *xdr)
145 {
146 return true;
147 }
148
149 bool
150 nlm4svc_decode_testargs(struct svc_rqst *rqstp, struct xdr_stream *xdr)
151 {
152 struct nlm_args *argp = rqstp->rq_argp;
153 u32 exclusive;
154
155 if (!svcxdr_decode_cookie(xdr, &argp->cookie))
156 return false;
157 if (xdr_stream_decode_bool(xdr, &exclusive) < 0)
158 return false;
159 if (!svcxdr_decode_lock(xdr, &argp->lock))
160 return false;
161 if (exclusive)
162 argp->lock.fl.c.flc_type = F_WRLCK;
163
164 return true;
165 }
166
167 bool
168 nlm4svc_decode_lockargs(struct svc_rqst *rqstp, struct xdr_stream *xdr)
169 {
170 struct nlm_args *argp = rqstp->rq_argp;
171 u32 exclusive;
172
173 if (!svcxdr_decode_cookie(xdr, &argp->cookie))
174 return false;
175 if (xdr_stream_decode_bool(xdr, &argp->block) < 0)
176 return false;
177 if (xdr_stream_decode_bool(xdr, &exclusive) < 0)
178 return false;
179 if (!svcxdr_decode_lock(xdr, &argp->lock))
180 return false;
181 if (exclusive)
182 argp->lock.fl.c.flc_type = F_WRLCK;
183 if (xdr_stream_decode_bool(xdr, &argp->reclaim) < 0)
184 return false;
185 if (xdr_stream_decode_u32(xdr, &argp->state) < 0)
186 return false;
187 argp->monitor = 1; /* monitor client by default */
188
189 return true;
190 }
191
192 bool
193 nlm4svc_decode_cancargs(struct svc_rqst *rqstp, struct xdr_stream *xdr)
194 {
195 struct nlm_args *argp = rqstp->rq_argp;
196 u32 exclusive;
197
198 if (!svcxdr_decode_cookie(xdr, &argp->cookie))
199 return false;
200 if (xdr_stream_decode_bool(xdr, &argp->block) < 0)
201 return false;
202 if (xdr_stream_decode_bool(xdr, &exclusive) < 0)
203 return false;
204 if (!svcxdr_decode_lock(xdr, &argp->lock))
205 return false;
206 if (exclusive)
207 argp->lock.fl.c.flc_type = F_WRLCK;
208
209 return true;
210 }
211
212 bool
213 nlm4svc_decode_unlockargs(struct svc_rqst *rqstp, struct xdr_stream *xdr)
214 {
215 struct nlm_args *argp = rqstp->rq_argp;
216
217 if (!svcxdr_decode_cookie(xdr, &argp->cookie))
218 return false;
219 if (!svcxdr_decode_lock(xdr, &argp->lock))
220 return false;
221 argp->lock.fl.c.flc_type = F_UNLCK;
222
223 return true;
224 }
225
226 bool
227 nlm4svc_decode_res(struct svc_rqst *rqstp, struct xdr_stream *xdr)
228 {
229 struct nlm_res *resp = rqstp->rq_argp;
230
231 if (!svcxdr_decode_cookie(xdr, &resp->cookie))
232 return false;
233 if (!svcxdr_decode_stats(xdr, &resp->status))
234 return false;
235
236 return true;
237 }
238
239 bool
240 nlm4svc_decode_reboot(struct svc_rqst *rqstp, struct xdr_stream *xdr)
241 {
242 struct nlm_reboot *argp = rqstp->rq_argp;
243 __be32 *p;
244 u32 len;
245
246 if (xdr_stream_decode_u32(xdr, &len) < 0)
247 return false;
248 if (len > SM_MAXSTRLEN)
249 return false;
250 p = xdr_inline_decode(xdr, len);
251 if (!p)
252 return false;
253 argp->len = len;
254 argp->mon = (char *)p;
255 if (xdr_stream_decode_u32(xdr, &argp->state) < 0)
256 return false;
257 p = xdr_inline_decode(xdr, SM_PRIV_SIZE);
258 if (!p)
259 return false;
260 memcpy(&argp->priv.data, p, sizeof(argp->priv.data));
261
262 return true;
263 }
264
265 bool
266 nlm4svc_decode_shareargs(struct svc_rqst *rqstp, struct xdr_stream *xdr)
267 {
268 struct nlm_args *argp = rqstp->rq_argp;
269 struct nlm_lock *lock = &argp->lock;
270
271 memset(lock, 0, sizeof(*lock));
272 locks_init_lock(&lock->fl);
273 lock->svid = ~(u32)0;
274
275 if (!svcxdr_decode_cookie(xdr, &argp->cookie))
276 return false;
277 if (!svcxdr_decode_string(xdr, &lock->caller, &lock->len))
278 return false;
279 if (!svcxdr_decode_fhandle(xdr, &lock->fh))
280 return false;
281 if (!svcxdr_decode_owner(xdr, &lock->oh))
282 return false;
283 /* XXX: Range checks are missing in the original code */
284 if (xdr_stream_decode_u32(xdr, &argp->fsm_mode) < 0)
285 return false;
286 if (xdr_stream_decode_u32(xdr, &argp->fsm_access) < 0)
287 return false;
288
289 return true;
290 }
291
292 bool
293 nlm4svc_decode_notify(struct svc_rqst *rqstp, struct xdr_stream *xdr)
294 {
295 struct nlm_args *argp = rqstp->rq_argp;
296 struct nlm_lock *lock = &argp->lock;
297
298 if (!svcxdr_decode_string(xdr, &lock->caller, &lock->len))
299 return false;
300 if (xdr_stream_decode_u32(xdr, &argp->state) < 0)
301 return false;
302
303 return true;
304 }
305
306
307 /*
308 * Encode Reply results
309 */
310
311 bool
312 nlm4svc_encode_void(struct svc_rqst *rqstp, struct xdr_stream *xdr)
313 {
314 return true;
315 }
316
317 bool
318 nlm4svc_encode_testres(struct svc_rqst *rqstp, struct xdr_stream *xdr)
319 {
320 struct nlm_res *resp = rqstp->rq_resp;
321
322 return svcxdr_encode_cookie(xdr, &resp->cookie) &&
323 svcxdr_encode_testrply(xdr, resp);
324 }
325
326 bool
327 nlm4svc_encode_res(struct svc_rqst *rqstp, struct xdr_stream *xdr)
328 {
329 struct nlm_res *resp = rqstp->rq_resp;
330
331 return svcxdr_encode_cookie(xdr, &resp->cookie) &&
332 svcxdr_encode_stats(xdr, resp->status);
333 }
334
335 bool
336 nlm4svc_encode_shareres(struct svc_rqst *rqstp, struct xdr_stream *xdr)
337 {
338 struct nlm_res *resp = rqstp->rq_resp;
339
340 if (!svcxdr_encode_cookie(xdr, &resp->cookie))
341 return false;
342 if (!svcxdr_encode_stats(xdr, resp->status))
343 return false;
344 /* sequence */
345 if (xdr_stream_encode_u32(xdr, 0) < 0)
346 return false;
347
348 return true;
349 }
350
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