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
23static inline s64
24loff_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
36void 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 */
52static bool
53svcxdr_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, ptr: &len) < 0)
59 return false;
60 if (len > NFS_MAXFHSIZE)
61 return false;
62
63 p = xdr_inline_decode(xdr, nbytes: len);
64 if (!p)
65 return false;
66 fh->size = len;
67 memcpy(to: fh->data, from: p, len);
68 memset(s: fh->data + len, c: 0, n: sizeof(fh->data) - len);
69
70 return true;
71}
72
73static bool
74svcxdr_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, data: &lock->caller, data_len: &lock->len))
79 return false;
80 if (!svcxdr_decode_fhandle(xdr, fh: &lock->fh))
81 return false;
82 if (!svcxdr_decode_owner(xdr, obj: &lock->oh))
83 return false;
84 if (xdr_stream_decode_u32(xdr, ptr: &lock->svid) < 0)
85 return false;
86 if (xdr_stream_decode_u64(xdr, ptr: &lock->lock_start) < 0)
87 return false;
88 if (xdr_stream_decode_u64(xdr, ptr: &lock->lock_len) < 0)
89 return false;
90
91 locks_init_lock(fl);
92 fl->c.flc_type = F_RDLCK;
93 nlm4svc_set_file_lock_range(fl, off: lock->lock_start, len: lock->lock_len);
94 return true;
95}
96
97static bool
98svcxdr_encode_holder(struct xdr_stream *xdr, const struct nlm_lock *lock)
99{
100 const struct file_lock *fl = &lock->fl;
101 s64 start, len;
102
103 /* exclusive */
104 if (xdr_stream_encode_bool(xdr, n: fl->c.flc_type != F_RDLCK) < 0)
105 return false;
106 if (xdr_stream_encode_u32(xdr, n: lock->svid) < 0)
107 return false;
108 if (!svcxdr_encode_owner(xdr, obj: &lock->oh))
109 return false;
110 start = loff_t_to_s64(offset: fl->fl_start);
111 if (fl->fl_end == OFFSET_MAX)
112 len = 0;
113 else
114 len = loff_t_to_s64(offset: fl->fl_end - fl->fl_start + 1);
115 if (xdr_stream_encode_u64(xdr, n: start) < 0)
116 return false;
117 if (xdr_stream_encode_u64(xdr, n: len) < 0)
118 return false;
119
120 return true;
121}
122
123static bool
124svcxdr_encode_testrply(struct xdr_stream *xdr, const struct nlm_res *resp)
125{
126 if (!svcxdr_encode_stats(xdr, status: resp->status))
127 return false;
128 switch (resp->status) {
129 case nlm_lck_denied:
130 if (!svcxdr_encode_holder(xdr, lock: &resp->lock))
131 return false;
132 }
133
134 return true;
135}
136
137
138/*
139 * Decode Call arguments
140 */
141
142bool
143nlm4svc_decode_void(struct svc_rqst *rqstp, struct xdr_stream *xdr)
144{
145 return true;
146}
147
148bool
149nlm4svc_decode_testargs(struct svc_rqst *rqstp, struct xdr_stream *xdr)
150{
151 struct nlm_args *argp = rqstp->rq_argp;
152 u32 exclusive;
153
154 if (!svcxdr_decode_cookie(xdr, cookie: &argp->cookie))
155 return false;
156 if (xdr_stream_decode_bool(xdr, ptr: &exclusive) < 0)
157 return false;
158 if (!svcxdr_decode_lock(xdr, lock: &argp->lock))
159 return false;
160 if (exclusive)
161 argp->lock.fl.c.flc_type = F_WRLCK;
162
163 return true;
164}
165
166bool
167nlm4svc_decode_lockargs(struct svc_rqst *rqstp, struct xdr_stream *xdr)
168{
169 struct nlm_args *argp = rqstp->rq_argp;
170 u32 exclusive;
171
172 if (!svcxdr_decode_cookie(xdr, cookie: &argp->cookie))
173 return false;
174 if (xdr_stream_decode_bool(xdr, ptr: &argp->block) < 0)
175 return false;
176 if (xdr_stream_decode_bool(xdr, ptr: &exclusive) < 0)
177 return false;
178 if (!svcxdr_decode_lock(xdr, lock: &argp->lock))
179 return false;
180 if (exclusive)
181 argp->lock.fl.c.flc_type = F_WRLCK;
182 if (xdr_stream_decode_bool(xdr, ptr: &argp->reclaim) < 0)
183 return false;
184 if (xdr_stream_decode_u32(xdr, ptr: &argp->state) < 0)
185 return false;
186 argp->monitor = 1; /* monitor client by default */
187
188 return true;
189}
190
191bool
192nlm4svc_decode_cancargs(struct svc_rqst *rqstp, struct xdr_stream *xdr)
193{
194 struct nlm_args *argp = rqstp->rq_argp;
195 u32 exclusive;
196
197 if (!svcxdr_decode_cookie(xdr, cookie: &argp->cookie))
198 return false;
199 if (xdr_stream_decode_bool(xdr, ptr: &argp->block) < 0)
200 return false;
201 if (xdr_stream_decode_bool(xdr, ptr: &exclusive) < 0)
202 return false;
203 if (!svcxdr_decode_lock(xdr, lock: &argp->lock))
204 return false;
205 if (exclusive)
206 argp->lock.fl.c.flc_type = F_WRLCK;
207
208 return true;
209}
210
211bool
212nlm4svc_decode_unlockargs(struct svc_rqst *rqstp, struct xdr_stream *xdr)
213{
214 struct nlm_args *argp = rqstp->rq_argp;
215
216 if (!svcxdr_decode_cookie(xdr, cookie: &argp->cookie))
217 return false;
218 if (!svcxdr_decode_lock(xdr, lock: &argp->lock))
219 return false;
220 argp->lock.fl.c.flc_type = F_UNLCK;
221
222 return true;
223}
224
225bool
226nlm4svc_decode_res(struct svc_rqst *rqstp, struct xdr_stream *xdr)
227{
228 struct nlm_res *resp = rqstp->rq_argp;
229
230 if (!svcxdr_decode_cookie(xdr, cookie: &resp->cookie))
231 return false;
232 if (!svcxdr_decode_stats(xdr, status: &resp->status))
233 return false;
234
235 return true;
236}
237
238bool
239nlm4svc_decode_reboot(struct svc_rqst *rqstp, struct xdr_stream *xdr)
240{
241 struct nlm_reboot *argp = rqstp->rq_argp;
242 __be32 *p;
243 u32 len;
244
245 if (xdr_stream_decode_u32(xdr, ptr: &len) < 0)
246 return false;
247 if (len > SM_MAXSTRLEN)
248 return false;
249 p = xdr_inline_decode(xdr, nbytes: len);
250 if (!p)
251 return false;
252 argp->len = len;
253 argp->mon = (char *)p;
254 if (xdr_stream_decode_u32(xdr, ptr: &argp->state) < 0)
255 return false;
256 p = xdr_inline_decode(xdr, SM_PRIV_SIZE);
257 if (!p)
258 return false;
259 memcpy(to: &argp->priv.data, from: p, len: sizeof(argp->priv.data));
260
261 return true;
262}
263
264bool
265nlm4svc_decode_shareargs(struct svc_rqst *rqstp, struct xdr_stream *xdr)
266{
267 struct nlm_args *argp = rqstp->rq_argp;
268 struct nlm_lock *lock = &argp->lock;
269
270 locks_init_lock(&lock->fl);
271 lock->svid = ~(u32)0;
272
273 if (!svcxdr_decode_cookie(xdr, cookie: &argp->cookie))
274 return false;
275 if (!svcxdr_decode_string(xdr, data: &lock->caller, data_len: &lock->len))
276 return false;
277 if (!svcxdr_decode_fhandle(xdr, fh: &lock->fh))
278 return false;
279 if (!svcxdr_decode_owner(xdr, obj: &lock->oh))
280 return false;
281 /* XXX: Range checks are missing in the original code */
282 if (xdr_stream_decode_u32(xdr, ptr: &argp->fsm_mode) < 0)
283 return false;
284 if (xdr_stream_decode_u32(xdr, ptr: &argp->fsm_access) < 0)
285 return false;
286
287 return true;
288}
289
290bool
291nlm4svc_decode_notify(struct svc_rqst *rqstp, struct xdr_stream *xdr)
292{
293 struct nlm_args *argp = rqstp->rq_argp;
294 struct nlm_lock *lock = &argp->lock;
295
296 if (!svcxdr_decode_string(xdr, data: &lock->caller, data_len: &lock->len))
297 return false;
298 if (xdr_stream_decode_u32(xdr, ptr: &argp->state) < 0)
299 return false;
300
301 return true;
302}
303
304
305/*
306 * Encode Reply results
307 */
308
309bool
310nlm4svc_encode_void(struct svc_rqst *rqstp, struct xdr_stream *xdr)
311{
312 return true;
313}
314
315bool
316nlm4svc_encode_testres(struct svc_rqst *rqstp, struct xdr_stream *xdr)
317{
318 struct nlm_res *resp = rqstp->rq_resp;
319
320 return svcxdr_encode_cookie(xdr, cookie: &resp->cookie) &&
321 svcxdr_encode_testrply(xdr, resp);
322}
323
324bool
325nlm4svc_encode_res(struct svc_rqst *rqstp, struct xdr_stream *xdr)
326{
327 struct nlm_res *resp = rqstp->rq_resp;
328
329 return svcxdr_encode_cookie(xdr, cookie: &resp->cookie) &&
330 svcxdr_encode_stats(xdr, status: resp->status);
331}
332
333bool
334nlm4svc_encode_shareres(struct svc_rqst *rqstp, struct xdr_stream *xdr)
335{
336 struct nlm_res *resp = rqstp->rq_resp;
337
338 if (!svcxdr_encode_cookie(xdr, cookie: &resp->cookie))
339 return false;
340 if (!svcxdr_encode_stats(xdr, status: resp->status))
341 return false;
342 /* sequence */
343 if (xdr_stream_encode_u32(xdr, n: 0) < 0)
344 return false;
345
346 return true;
347}
348