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 loff_t
s64_to_loff_t(__s64 offset)24 s64_to_loff_t(__s64 offset)
25 {
26 return (loff_t)offset;
27 }
28
29
30 static inline s64
loff_t_to_s64(loff_t offset)31 loff_t_to_s64(loff_t offset)
32 {
33 s64 res;
34 if (offset > NLM4_OFFSET_MAX)
35 res = NLM4_OFFSET_MAX;
36 else if (offset < -NLM4_OFFSET_MAX)
37 res = -NLM4_OFFSET_MAX;
38 else
39 res = offset;
40 return res;
41 }
42
43 /*
44 * NLM file handles are defined by specification to be a variable-length
45 * XDR opaque no longer than 1024 bytes. However, this implementation
46 * limits their length to the size of an NFSv3 file handle.
47 */
48 static bool
svcxdr_decode_fhandle(struct xdr_stream * xdr,struct nfs_fh * fh)49 svcxdr_decode_fhandle(struct xdr_stream *xdr, struct nfs_fh *fh)
50 {
51 __be32 *p;
52 u32 len;
53
54 if (xdr_stream_decode_u32(xdr, &len) < 0)
55 return false;
56 if (len > NFS_MAXFHSIZE)
57 return false;
58
59 p = xdr_inline_decode(xdr, len);
60 if (!p)
61 return false;
62 fh->size = len;
63 memcpy(fh->data, p, len);
64 memset(fh->data + len, 0, sizeof(fh->data) - len);
65
66 return true;
67 }
68
69 static bool
svcxdr_decode_lock(struct xdr_stream * xdr,struct nlm_lock * lock)70 svcxdr_decode_lock(struct xdr_stream *xdr, struct nlm_lock *lock)
71 {
72 struct file_lock *fl = &lock->fl;
73 u64 len, start;
74 s64 end;
75
76 if (!svcxdr_decode_string(xdr, &lock->caller, &lock->len))
77 return false;
78 if (!svcxdr_decode_fhandle(xdr, &lock->fh))
79 return false;
80 if (!svcxdr_decode_owner(xdr, &lock->oh))
81 return false;
82 if (xdr_stream_decode_u32(xdr, &lock->svid) < 0)
83 return false;
84 if (xdr_stream_decode_u64(xdr, &start) < 0)
85 return false;
86 if (xdr_stream_decode_u64(xdr, &len) < 0)
87 return false;
88
89 locks_init_lock(fl);
90 fl->fl_flags = FL_POSIX;
91 fl->fl_type = F_RDLCK;
92 end = start + len - 1;
93 fl->fl_start = s64_to_loff_t(start);
94 if (len == 0 || end < 0)
95 fl->fl_end = OFFSET_MAX;
96 else
97 fl->fl_end = s64_to_loff_t(end);
98
99 return true;
100 }
101
102 static bool
svcxdr_encode_holder(struct xdr_stream * xdr,const struct nlm_lock * lock)103 svcxdr_encode_holder(struct xdr_stream *xdr, const struct nlm_lock *lock)
104 {
105 const struct file_lock *fl = &lock->fl;
106 s64 start, len;
107
108 /* exclusive */
109 if (xdr_stream_encode_bool(xdr, fl->fl_type != F_RDLCK) < 0)
110 return false;
111 if (xdr_stream_encode_u32(xdr, lock->svid) < 0)
112 return false;
113 if (!svcxdr_encode_owner(xdr, &lock->oh))
114 return false;
115 start = loff_t_to_s64(fl->fl_start);
116 if (fl->fl_end == OFFSET_MAX)
117 len = 0;
118 else
119 len = loff_t_to_s64(fl->fl_end - fl->fl_start + 1);
120 if (xdr_stream_encode_u64(xdr, start) < 0)
121 return false;
122 if (xdr_stream_encode_u64(xdr, len) < 0)
123 return false;
124
125 return true;
126 }
127
128 static bool
svcxdr_encode_testrply(struct xdr_stream * xdr,const struct nlm_res * resp)129 svcxdr_encode_testrply(struct xdr_stream *xdr, const struct nlm_res *resp)
130 {
131 if (!svcxdr_encode_stats(xdr, resp->status))
132 return false;
133 switch (resp->status) {
134 case nlm_lck_denied:
135 if (!svcxdr_encode_holder(xdr, &resp->lock))
136 return false;
137 }
138
139 return true;
140 }
141
142
143 /*
144 * Decode Call arguments
145 */
146
147 bool
nlm4svc_decode_void(struct svc_rqst * rqstp,struct xdr_stream * xdr)148 nlm4svc_decode_void(struct svc_rqst *rqstp, struct xdr_stream *xdr)
149 {
150 return true;
151 }
152
153 bool
nlm4svc_decode_testargs(struct svc_rqst * rqstp,struct xdr_stream * xdr)154 nlm4svc_decode_testargs(struct svc_rqst *rqstp, struct xdr_stream *xdr)
155 {
156 struct nlm_args *argp = rqstp->rq_argp;
157 u32 exclusive;
158
159 if (!svcxdr_decode_cookie(xdr, &argp->cookie))
160 return false;
161 if (xdr_stream_decode_bool(xdr, &exclusive) < 0)
162 return false;
163 if (!svcxdr_decode_lock(xdr, &argp->lock))
164 return false;
165 if (exclusive)
166 argp->lock.fl.fl_type = F_WRLCK;
167
168 return true;
169 }
170
171 bool
nlm4svc_decode_lockargs(struct svc_rqst * rqstp,struct xdr_stream * xdr)172 nlm4svc_decode_lockargs(struct svc_rqst *rqstp, struct xdr_stream *xdr)
173 {
174 struct nlm_args *argp = rqstp->rq_argp;
175 u32 exclusive;
176
177 if (!svcxdr_decode_cookie(xdr, &argp->cookie))
178 return false;
179 if (xdr_stream_decode_bool(xdr, &argp->block) < 0)
180 return false;
181 if (xdr_stream_decode_bool(xdr, &exclusive) < 0)
182 return false;
183 if (!svcxdr_decode_lock(xdr, &argp->lock))
184 return false;
185 if (exclusive)
186 argp->lock.fl.fl_type = F_WRLCK;
187 if (xdr_stream_decode_bool(xdr, &argp->reclaim) < 0)
188 return false;
189 if (xdr_stream_decode_u32(xdr, &argp->state) < 0)
190 return false;
191 argp->monitor = 1; /* monitor client by default */
192
193 return true;
194 }
195
196 bool
nlm4svc_decode_cancargs(struct svc_rqst * rqstp,struct xdr_stream * xdr)197 nlm4svc_decode_cancargs(struct svc_rqst *rqstp, struct xdr_stream *xdr)
198 {
199 struct nlm_args *argp = rqstp->rq_argp;
200 u32 exclusive;
201
202 if (!svcxdr_decode_cookie(xdr, &argp->cookie))
203 return false;
204 if (xdr_stream_decode_bool(xdr, &argp->block) < 0)
205 return false;
206 if (xdr_stream_decode_bool(xdr, &exclusive) < 0)
207 return false;
208 if (!svcxdr_decode_lock(xdr, &argp->lock))
209 return false;
210 if (exclusive)
211 argp->lock.fl.fl_type = F_WRLCK;
212
213 return true;
214 }
215
216 bool
nlm4svc_decode_unlockargs(struct svc_rqst * rqstp,struct xdr_stream * xdr)217 nlm4svc_decode_unlockargs(struct svc_rqst *rqstp, struct xdr_stream *xdr)
218 {
219 struct nlm_args *argp = rqstp->rq_argp;
220
221 if (!svcxdr_decode_cookie(xdr, &argp->cookie))
222 return false;
223 if (!svcxdr_decode_lock(xdr, &argp->lock))
224 return false;
225 argp->lock.fl.fl_type = F_UNLCK;
226
227 return true;
228 }
229
230 bool
nlm4svc_decode_res(struct svc_rqst * rqstp,struct xdr_stream * xdr)231 nlm4svc_decode_res(struct svc_rqst *rqstp, struct xdr_stream *xdr)
232 {
233 struct nlm_res *resp = rqstp->rq_argp;
234
235 if (!svcxdr_decode_cookie(xdr, &resp->cookie))
236 return false;
237 if (!svcxdr_decode_stats(xdr, &resp->status))
238 return false;
239
240 return true;
241 }
242
243 bool
nlm4svc_decode_reboot(struct svc_rqst * rqstp,struct xdr_stream * xdr)244 nlm4svc_decode_reboot(struct svc_rqst *rqstp, struct xdr_stream *xdr)
245 {
246 struct nlm_reboot *argp = rqstp->rq_argp;
247 __be32 *p;
248 u32 len;
249
250 if (xdr_stream_decode_u32(xdr, &len) < 0)
251 return false;
252 if (len > SM_MAXSTRLEN)
253 return false;
254 p = xdr_inline_decode(xdr, len);
255 if (!p)
256 return false;
257 argp->len = len;
258 argp->mon = (char *)p;
259 if (xdr_stream_decode_u32(xdr, &argp->state) < 0)
260 return false;
261 p = xdr_inline_decode(xdr, SM_PRIV_SIZE);
262 if (!p)
263 return false;
264 memcpy(&argp->priv.data, p, sizeof(argp->priv.data));
265
266 return true;
267 }
268
269 bool
nlm4svc_decode_shareargs(struct svc_rqst * rqstp,struct xdr_stream * xdr)270 nlm4svc_decode_shareargs(struct svc_rqst *rqstp, struct xdr_stream *xdr)
271 {
272 struct nlm_args *argp = rqstp->rq_argp;
273 struct nlm_lock *lock = &argp->lock;
274
275 memset(lock, 0, sizeof(*lock));
276 locks_init_lock(&lock->fl);
277 lock->svid = ~(u32)0;
278
279 if (!svcxdr_decode_cookie(xdr, &argp->cookie))
280 return false;
281 if (!svcxdr_decode_string(xdr, &lock->caller, &lock->len))
282 return false;
283 if (!svcxdr_decode_fhandle(xdr, &lock->fh))
284 return false;
285 if (!svcxdr_decode_owner(xdr, &lock->oh))
286 return false;
287 /* XXX: Range checks are missing in the original code */
288 if (xdr_stream_decode_u32(xdr, &argp->fsm_mode) < 0)
289 return false;
290 if (xdr_stream_decode_u32(xdr, &argp->fsm_access) < 0)
291 return false;
292
293 return true;
294 }
295
296 bool
nlm4svc_decode_notify(struct svc_rqst * rqstp,struct xdr_stream * xdr)297 nlm4svc_decode_notify(struct svc_rqst *rqstp, struct xdr_stream *xdr)
298 {
299 struct nlm_args *argp = rqstp->rq_argp;
300 struct nlm_lock *lock = &argp->lock;
301
302 if (!svcxdr_decode_string(xdr, &lock->caller, &lock->len))
303 return false;
304 if (xdr_stream_decode_u32(xdr, &argp->state) < 0)
305 return false;
306
307 return true;
308 }
309
310
311 /*
312 * Encode Reply results
313 */
314
315 bool
nlm4svc_encode_void(struct svc_rqst * rqstp,struct xdr_stream * xdr)316 nlm4svc_encode_void(struct svc_rqst *rqstp, struct xdr_stream *xdr)
317 {
318 return true;
319 }
320
321 bool
nlm4svc_encode_testres(struct svc_rqst * rqstp,struct xdr_stream * xdr)322 nlm4svc_encode_testres(struct svc_rqst *rqstp, struct xdr_stream *xdr)
323 {
324 struct nlm_res *resp = rqstp->rq_resp;
325
326 return svcxdr_encode_cookie(xdr, &resp->cookie) &&
327 svcxdr_encode_testrply(xdr, resp);
328 }
329
330 bool
nlm4svc_encode_res(struct svc_rqst * rqstp,struct xdr_stream * xdr)331 nlm4svc_encode_res(struct svc_rqst *rqstp, struct xdr_stream *xdr)
332 {
333 struct nlm_res *resp = rqstp->rq_resp;
334
335 return svcxdr_encode_cookie(xdr, &resp->cookie) &&
336 svcxdr_encode_stats(xdr, resp->status);
337 }
338
339 bool
nlm4svc_encode_shareres(struct svc_rqst * rqstp,struct xdr_stream * xdr)340 nlm4svc_encode_shareres(struct svc_rqst *rqstp, struct xdr_stream *xdr)
341 {
342 struct nlm_res *resp = rqstp->rq_resp;
343
344 if (!svcxdr_encode_cookie(xdr, &resp->cookie))
345 return false;
346 if (!svcxdr_encode_stats(xdr, resp->status))
347 return false;
348 /* sequence */
349 if (xdr_stream_encode_u32(xdr, 0) < 0)
350 return false;
351
352 return true;
353 }
354