1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * linux/fs/lockd/xdr.c
4 *
5 * XDR support for lockd and the lock client.
6 *
7 * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
8 */
9
10 #include <linux/types.h>
11 #include <linux/sched.h>
12 #include <linux/nfs.h>
13
14 #include <linux/sunrpc/xdr.h>
15 #include <linux/sunrpc/clnt.h>
16 #include <linux/sunrpc/svc.h>
17 #include <linux/sunrpc/stats.h>
18 #include <linux/lockd/lockd.h>
19
20 #include <uapi/linux/nfs2.h>
21
22 #define NLMDBG_FACILITY NLMDBG_XDR
23
24
25 static inline loff_t
s32_to_loff_t(__s32 offset)26 s32_to_loff_t(__s32 offset)
27 {
28 return (loff_t)offset;
29 }
30
31 static inline __s32
loff_t_to_s32(loff_t offset)32 loff_t_to_s32(loff_t offset)
33 {
34 __s32 res;
35 if (offset >= NLM_OFFSET_MAX)
36 res = NLM_OFFSET_MAX;
37 else if (offset <= -NLM_OFFSET_MAX)
38 res = -NLM_OFFSET_MAX;
39 else
40 res = offset;
41 return res;
42 }
43
44 /*
45 * XDR functions for basic NLM types
46 */
nlm_decode_cookie(__be32 * p,struct nlm_cookie * c)47 static __be32 *nlm_decode_cookie(__be32 *p, struct nlm_cookie *c)
48 {
49 unsigned int len;
50
51 len = ntohl(*p++);
52
53 if(len==0)
54 {
55 c->len=4;
56 memset(c->data, 0, 4); /* hockeypux brain damage */
57 }
58 else if(len<=NLM_MAXCOOKIELEN)
59 {
60 c->len=len;
61 memcpy(c->data, p, len);
62 p+=XDR_QUADLEN(len);
63 }
64 else
65 {
66 dprintk("lockd: bad cookie size %d (only cookies under "
67 "%d bytes are supported.)\n",
68 len, NLM_MAXCOOKIELEN);
69 return NULL;
70 }
71 return p;
72 }
73
74 static inline __be32 *
nlm_encode_cookie(__be32 * p,struct nlm_cookie * c)75 nlm_encode_cookie(__be32 *p, struct nlm_cookie *c)
76 {
77 *p++ = htonl(c->len);
78 memcpy(p, c->data, c->len);
79 p+=XDR_QUADLEN(c->len);
80 return p;
81 }
82
83 static __be32 *
nlm_decode_fh(__be32 * p,struct nfs_fh * f)84 nlm_decode_fh(__be32 *p, struct nfs_fh *f)
85 {
86 unsigned int len;
87
88 if ((len = ntohl(*p++)) != NFS2_FHSIZE) {
89 dprintk("lockd: bad fhandle size %d (should be %d)\n",
90 len, NFS2_FHSIZE);
91 return NULL;
92 }
93 f->size = NFS2_FHSIZE;
94 memset(f->data, 0, sizeof(f->data));
95 memcpy(f->data, p, NFS2_FHSIZE);
96 return p + XDR_QUADLEN(NFS2_FHSIZE);
97 }
98
99 /*
100 * Encode and decode owner handle
101 */
102 static inline __be32 *
nlm_decode_oh(__be32 * p,struct xdr_netobj * oh)103 nlm_decode_oh(__be32 *p, struct xdr_netobj *oh)
104 {
105 return xdr_decode_netobj(p, oh);
106 }
107
108 static inline __be32 *
nlm_encode_oh(__be32 * p,struct xdr_netobj * oh)109 nlm_encode_oh(__be32 *p, struct xdr_netobj *oh)
110 {
111 return xdr_encode_netobj(p, oh);
112 }
113
114 static __be32 *
nlm_decode_lock(__be32 * p,struct nlm_lock * lock)115 nlm_decode_lock(__be32 *p, struct nlm_lock *lock)
116 {
117 struct file_lock *fl = &lock->fl;
118 s32 start, len, end;
119
120 if (!(p = xdr_decode_string_inplace(p, &lock->caller,
121 &lock->len,
122 NLM_MAXSTRLEN))
123 || !(p = nlm_decode_fh(p, &lock->fh))
124 || !(p = nlm_decode_oh(p, &lock->oh)))
125 return NULL;
126 lock->svid = ntohl(*p++);
127
128 locks_init_lock(fl);
129 fl->fl_flags = FL_POSIX;
130 fl->fl_type = F_RDLCK; /* as good as anything else */
131 start = ntohl(*p++);
132 len = ntohl(*p++);
133 end = start + len - 1;
134
135 fl->fl_start = s32_to_loff_t(start);
136
137 if (len == 0 || end < 0)
138 fl->fl_end = OFFSET_MAX;
139 else
140 fl->fl_end = s32_to_loff_t(end);
141 return p;
142 }
143
144 /*
145 * Encode result of a TEST/TEST_MSG call
146 */
147 static __be32 *
nlm_encode_testres(__be32 * p,struct nlm_res * resp)148 nlm_encode_testres(__be32 *p, struct nlm_res *resp)
149 {
150 s32 start, len;
151
152 if (!(p = nlm_encode_cookie(p, &resp->cookie)))
153 return NULL;
154 *p++ = resp->status;
155
156 if (resp->status == nlm_lck_denied) {
157 struct file_lock *fl = &resp->lock.fl;
158
159 *p++ = (fl->fl_type == F_RDLCK)? xdr_zero : xdr_one;
160 *p++ = htonl(resp->lock.svid);
161
162 /* Encode owner handle. */
163 if (!(p = xdr_encode_netobj(p, &resp->lock.oh)))
164 return NULL;
165
166 start = loff_t_to_s32(fl->fl_start);
167 if (fl->fl_end == OFFSET_MAX)
168 len = 0;
169 else
170 len = loff_t_to_s32(fl->fl_end - fl->fl_start + 1);
171
172 *p++ = htonl(start);
173 *p++ = htonl(len);
174 }
175
176 return p;
177 }
178
179
180 /*
181 * First, the server side XDR functions
182 */
183 int
nlmsvc_decode_testargs(struct svc_rqst * rqstp,__be32 * p)184 nlmsvc_decode_testargs(struct svc_rqst *rqstp, __be32 *p)
185 {
186 struct nlm_args *argp = rqstp->rq_argp;
187 u32 exclusive;
188
189 if (!(p = nlm_decode_cookie(p, &argp->cookie)))
190 return 0;
191
192 exclusive = ntohl(*p++);
193 if (!(p = nlm_decode_lock(p, &argp->lock)))
194 return 0;
195 if (exclusive)
196 argp->lock.fl.fl_type = F_WRLCK;
197
198 return xdr_argsize_check(rqstp, p);
199 }
200
201 int
nlmsvc_encode_testres(struct svc_rqst * rqstp,__be32 * p)202 nlmsvc_encode_testres(struct svc_rqst *rqstp, __be32 *p)
203 {
204 struct nlm_res *resp = rqstp->rq_resp;
205
206 if (!(p = nlm_encode_testres(p, resp)))
207 return 0;
208 return xdr_ressize_check(rqstp, p);
209 }
210
211 int
nlmsvc_decode_lockargs(struct svc_rqst * rqstp,__be32 * p)212 nlmsvc_decode_lockargs(struct svc_rqst *rqstp, __be32 *p)
213 {
214 struct nlm_args *argp = rqstp->rq_argp;
215 u32 exclusive;
216
217 if (!(p = nlm_decode_cookie(p, &argp->cookie)))
218 return 0;
219 argp->block = ntohl(*p++);
220 exclusive = ntohl(*p++);
221 if (!(p = nlm_decode_lock(p, &argp->lock)))
222 return 0;
223 if (exclusive)
224 argp->lock.fl.fl_type = F_WRLCK;
225 argp->reclaim = ntohl(*p++);
226 argp->state = ntohl(*p++);
227 argp->monitor = 1; /* monitor client by default */
228
229 return xdr_argsize_check(rqstp, p);
230 }
231
232 int
nlmsvc_decode_cancargs(struct svc_rqst * rqstp,__be32 * p)233 nlmsvc_decode_cancargs(struct svc_rqst *rqstp, __be32 *p)
234 {
235 struct nlm_args *argp = rqstp->rq_argp;
236 u32 exclusive;
237
238 if (!(p = nlm_decode_cookie(p, &argp->cookie)))
239 return 0;
240 argp->block = ntohl(*p++);
241 exclusive = ntohl(*p++);
242 if (!(p = nlm_decode_lock(p, &argp->lock)))
243 return 0;
244 if (exclusive)
245 argp->lock.fl.fl_type = F_WRLCK;
246 return xdr_argsize_check(rqstp, p);
247 }
248
249 int
nlmsvc_decode_unlockargs(struct svc_rqst * rqstp,__be32 * p)250 nlmsvc_decode_unlockargs(struct svc_rqst *rqstp, __be32 *p)
251 {
252 struct nlm_args *argp = rqstp->rq_argp;
253
254 if (!(p = nlm_decode_cookie(p, &argp->cookie))
255 || !(p = nlm_decode_lock(p, &argp->lock)))
256 return 0;
257 argp->lock.fl.fl_type = F_UNLCK;
258 return xdr_argsize_check(rqstp, p);
259 }
260
261 int
nlmsvc_decode_shareargs(struct svc_rqst * rqstp,__be32 * p)262 nlmsvc_decode_shareargs(struct svc_rqst *rqstp, __be32 *p)
263 {
264 struct nlm_args *argp = rqstp->rq_argp;
265 struct nlm_lock *lock = &argp->lock;
266
267 memset(lock, 0, sizeof(*lock));
268 locks_init_lock(&lock->fl);
269 lock->svid = ~(u32) 0;
270
271 if (!(p = nlm_decode_cookie(p, &argp->cookie))
272 || !(p = xdr_decode_string_inplace(p, &lock->caller,
273 &lock->len, NLM_MAXSTRLEN))
274 || !(p = nlm_decode_fh(p, &lock->fh))
275 || !(p = nlm_decode_oh(p, &lock->oh)))
276 return 0;
277 argp->fsm_mode = ntohl(*p++);
278 argp->fsm_access = ntohl(*p++);
279 return xdr_argsize_check(rqstp, p);
280 }
281
282 int
nlmsvc_encode_shareres(struct svc_rqst * rqstp,__be32 * p)283 nlmsvc_encode_shareres(struct svc_rqst *rqstp, __be32 *p)
284 {
285 struct nlm_res *resp = rqstp->rq_resp;
286
287 if (!(p = nlm_encode_cookie(p, &resp->cookie)))
288 return 0;
289 *p++ = resp->status;
290 *p++ = xdr_zero; /* sequence argument */
291 return xdr_ressize_check(rqstp, p);
292 }
293
294 int
nlmsvc_encode_res(struct svc_rqst * rqstp,__be32 * p)295 nlmsvc_encode_res(struct svc_rqst *rqstp, __be32 *p)
296 {
297 struct nlm_res *resp = rqstp->rq_resp;
298
299 if (!(p = nlm_encode_cookie(p, &resp->cookie)))
300 return 0;
301 *p++ = resp->status;
302 return xdr_ressize_check(rqstp, p);
303 }
304
305 int
nlmsvc_decode_notify(struct svc_rqst * rqstp,__be32 * p)306 nlmsvc_decode_notify(struct svc_rqst *rqstp, __be32 *p)
307 {
308 struct nlm_args *argp = rqstp->rq_argp;
309 struct nlm_lock *lock = &argp->lock;
310
311 if (!(p = xdr_decode_string_inplace(p, &lock->caller,
312 &lock->len, NLM_MAXSTRLEN)))
313 return 0;
314 argp->state = ntohl(*p++);
315 return xdr_argsize_check(rqstp, p);
316 }
317
318 int
nlmsvc_decode_reboot(struct svc_rqst * rqstp,__be32 * p)319 nlmsvc_decode_reboot(struct svc_rqst *rqstp, __be32 *p)
320 {
321 struct nlm_reboot *argp = rqstp->rq_argp;
322
323 if (!(p = xdr_decode_string_inplace(p, &argp->mon, &argp->len, SM_MAXSTRLEN)))
324 return 0;
325 argp->state = ntohl(*p++);
326 memcpy(&argp->priv.data, p, sizeof(argp->priv.data));
327 p += XDR_QUADLEN(SM_PRIV_SIZE);
328 return xdr_argsize_check(rqstp, p);
329 }
330
331 int
nlmsvc_decode_res(struct svc_rqst * rqstp,__be32 * p)332 nlmsvc_decode_res(struct svc_rqst *rqstp, __be32 *p)
333 {
334 struct nlm_res *resp = rqstp->rq_argp;
335
336 if (!(p = nlm_decode_cookie(p, &resp->cookie)))
337 return 0;
338 resp->status = *p++;
339 return xdr_argsize_check(rqstp, p);
340 }
341
342 int
nlmsvc_decode_void(struct svc_rqst * rqstp,__be32 * p)343 nlmsvc_decode_void(struct svc_rqst *rqstp, __be32 *p)
344 {
345 return xdr_argsize_check(rqstp, p);
346 }
347
348 int
nlmsvc_encode_void(struct svc_rqst * rqstp,__be32 * p)349 nlmsvc_encode_void(struct svc_rqst *rqstp, __be32 *p)
350 {
351 return xdr_ressize_check(rqstp, p);
352 }
353