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
nlm4svc_set_file_lock_range(struct file_lock * fl,u64 off,u64 len)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
svcxdr_decode_fhandle(struct xdr_stream * xdr,struct nfs_fh * fh)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
svcxdr_decode_lock(struct xdr_stream * xdr,struct nlm_lock * lock)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->fl_flags = FL_POSIX;
93 fl->fl_type = F_RDLCK;
94 nlm4svc_set_file_lock_range(fl, lock->lock_start, lock->lock_len);
95 return true;
96 }
97
98 static bool
svcxdr_encode_holder(struct xdr_stream * xdr,const struct nlm_lock * lock)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->fl_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
svcxdr_encode_testrply(struct xdr_stream * xdr,const struct nlm_res * resp)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 int
nlm4svc_decode_void(struct svc_rqst * rqstp,__be32 * p)144 nlm4svc_decode_void(struct svc_rqst *rqstp, __be32 *p)
145 {
146 return 1;
147 }
148
149 int
nlm4svc_decode_testargs(struct svc_rqst * rqstp,__be32 * p)150 nlm4svc_decode_testargs(struct svc_rqst *rqstp, __be32 *p)
151 {
152 struct xdr_stream *xdr = &rqstp->rq_arg_stream;
153 struct nlm_args *argp = rqstp->rq_argp;
154 u32 exclusive;
155
156 if (!svcxdr_decode_cookie(xdr, &argp->cookie))
157 return 0;
158 if (xdr_stream_decode_bool(xdr, &exclusive) < 0)
159 return 0;
160 if (!svcxdr_decode_lock(xdr, &argp->lock))
161 return 0;
162 if (exclusive)
163 argp->lock.fl.fl_type = F_WRLCK;
164
165 return 1;
166 }
167
168 int
nlm4svc_decode_lockargs(struct svc_rqst * rqstp,__be32 * p)169 nlm4svc_decode_lockargs(struct svc_rqst *rqstp, __be32 *p)
170 {
171 struct xdr_stream *xdr = &rqstp->rq_arg_stream;
172 struct nlm_args *argp = rqstp->rq_argp;
173 u32 exclusive;
174
175 if (!svcxdr_decode_cookie(xdr, &argp->cookie))
176 return 0;
177 if (xdr_stream_decode_bool(xdr, &argp->block) < 0)
178 return 0;
179 if (xdr_stream_decode_bool(xdr, &exclusive) < 0)
180 return 0;
181 if (!svcxdr_decode_lock(xdr, &argp->lock))
182 return 0;
183 if (exclusive)
184 argp->lock.fl.fl_type = F_WRLCK;
185 if (xdr_stream_decode_bool(xdr, &argp->reclaim) < 0)
186 return 0;
187 if (xdr_stream_decode_u32(xdr, &argp->state) < 0)
188 return 0;
189 argp->monitor = 1; /* monitor client by default */
190
191 return 1;
192 }
193
194 int
nlm4svc_decode_cancargs(struct svc_rqst * rqstp,__be32 * p)195 nlm4svc_decode_cancargs(struct svc_rqst *rqstp, __be32 *p)
196 {
197 struct xdr_stream *xdr = &rqstp->rq_arg_stream;
198 struct nlm_args *argp = rqstp->rq_argp;
199 u32 exclusive;
200
201 if (!svcxdr_decode_cookie(xdr, &argp->cookie))
202 return 0;
203 if (xdr_stream_decode_bool(xdr, &argp->block) < 0)
204 return 0;
205 if (xdr_stream_decode_bool(xdr, &exclusive) < 0)
206 return 0;
207 if (!svcxdr_decode_lock(xdr, &argp->lock))
208 return 0;
209 if (exclusive)
210 argp->lock.fl.fl_type = F_WRLCK;
211 return 1;
212 }
213
214 int
nlm4svc_decode_unlockargs(struct svc_rqst * rqstp,__be32 * p)215 nlm4svc_decode_unlockargs(struct svc_rqst *rqstp, __be32 *p)
216 {
217 struct xdr_stream *xdr = &rqstp->rq_arg_stream;
218 struct nlm_args *argp = rqstp->rq_argp;
219
220 if (!svcxdr_decode_cookie(xdr, &argp->cookie))
221 return 0;
222 if (!svcxdr_decode_lock(xdr, &argp->lock))
223 return 0;
224 argp->lock.fl.fl_type = F_UNLCK;
225
226 return 1;
227 }
228
229 int
nlm4svc_decode_res(struct svc_rqst * rqstp,__be32 * p)230 nlm4svc_decode_res(struct svc_rqst *rqstp, __be32 *p)
231 {
232 struct xdr_stream *xdr = &rqstp->rq_arg_stream;
233 struct nlm_res *resp = rqstp->rq_argp;
234
235 if (!svcxdr_decode_cookie(xdr, &resp->cookie))
236 return 0;
237 if (!svcxdr_decode_stats(xdr, &resp->status))
238 return 0;
239
240 return 1;
241 }
242
243 int
nlm4svc_decode_reboot(struct svc_rqst * rqstp,__be32 * p)244 nlm4svc_decode_reboot(struct svc_rqst *rqstp, __be32 *p)
245 {
246 struct xdr_stream *xdr = &rqstp->rq_arg_stream;
247 struct nlm_reboot *argp = rqstp->rq_argp;
248 u32 len;
249
250 if (xdr_stream_decode_u32(xdr, &len) < 0)
251 return 0;
252 if (len > SM_MAXSTRLEN)
253 return 0;
254 p = xdr_inline_decode(xdr, len);
255 if (!p)
256 return 0;
257 argp->len = len;
258 argp->mon = (char *)p;
259 if (xdr_stream_decode_u32(xdr, &argp->state) < 0)
260 return 0;
261 p = xdr_inline_decode(xdr, SM_PRIV_SIZE);
262 if (!p)
263 return 0;
264 memcpy(&argp->priv.data, p, sizeof(argp->priv.data));
265
266 return 1;
267 }
268
269 int
nlm4svc_decode_shareargs(struct svc_rqst * rqstp,__be32 * p)270 nlm4svc_decode_shareargs(struct svc_rqst *rqstp, __be32 *p)
271 {
272 struct xdr_stream *xdr = &rqstp->rq_arg_stream;
273 struct nlm_args *argp = rqstp->rq_argp;
274 struct nlm_lock *lock = &argp->lock;
275
276 memset(lock, 0, sizeof(*lock));
277 locks_init_lock(&lock->fl);
278 lock->svid = ~(u32)0;
279
280 if (!svcxdr_decode_cookie(xdr, &argp->cookie))
281 return 0;
282 if (!svcxdr_decode_string(xdr, &lock->caller, &lock->len))
283 return 0;
284 if (!svcxdr_decode_fhandle(xdr, &lock->fh))
285 return 0;
286 if (!svcxdr_decode_owner(xdr, &lock->oh))
287 return 0;
288 /* XXX: Range checks are missing in the original code */
289 if (xdr_stream_decode_u32(xdr, &argp->fsm_mode) < 0)
290 return 0;
291 if (xdr_stream_decode_u32(xdr, &argp->fsm_access) < 0)
292 return 0;
293
294 return 1;
295 }
296
297 int
nlm4svc_decode_notify(struct svc_rqst * rqstp,__be32 * p)298 nlm4svc_decode_notify(struct svc_rqst *rqstp, __be32 *p)
299 {
300 struct xdr_stream *xdr = &rqstp->rq_arg_stream;
301 struct nlm_args *argp = rqstp->rq_argp;
302 struct nlm_lock *lock = &argp->lock;
303
304 if (!svcxdr_decode_string(xdr, &lock->caller, &lock->len))
305 return 0;
306 if (xdr_stream_decode_u32(xdr, &argp->state) < 0)
307 return 0;
308
309 return 1;
310 }
311
312
313 /*
314 * Encode Reply results
315 */
316
317 int
nlm4svc_encode_void(struct svc_rqst * rqstp,__be32 * p)318 nlm4svc_encode_void(struct svc_rqst *rqstp, __be32 *p)
319 {
320 return 1;
321 }
322
323 int
nlm4svc_encode_testres(struct svc_rqst * rqstp,__be32 * p)324 nlm4svc_encode_testres(struct svc_rqst *rqstp, __be32 *p)
325 {
326 struct xdr_stream *xdr = &rqstp->rq_res_stream;
327 struct nlm_res *resp = rqstp->rq_resp;
328
329 return svcxdr_encode_cookie(xdr, &resp->cookie) &&
330 svcxdr_encode_testrply(xdr, resp);
331 }
332
333 int
nlm4svc_encode_res(struct svc_rqst * rqstp,__be32 * p)334 nlm4svc_encode_res(struct svc_rqst *rqstp, __be32 *p)
335 {
336 struct xdr_stream *xdr = &rqstp->rq_res_stream;
337 struct nlm_res *resp = rqstp->rq_resp;
338
339 return svcxdr_encode_cookie(xdr, &resp->cookie) &&
340 svcxdr_encode_stats(xdr, resp->status);
341 }
342
343 int
nlm4svc_encode_shareres(struct svc_rqst * rqstp,__be32 * p)344 nlm4svc_encode_shareres(struct svc_rqst *rqstp, __be32 *p)
345 {
346 struct xdr_stream *xdr = &rqstp->rq_res_stream;
347 struct nlm_res *resp = rqstp->rq_resp;
348
349 if (!svcxdr_encode_cookie(xdr, &resp->cookie))
350 return 0;
351 if (!svcxdr_encode_stats(xdr, resp->status))
352 return 0;
353 /* sequence */
354 if (xdr_stream_encode_u32(xdr, 0) < 0)
355 return 0;
356
357 return 1;
358 }
359