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xdr4.c
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1 /*
2  * linux/fs/lockd/xdr4.c
3  *
4  * XDR support for lockd and the lock client.
5  *
6  * Copyright (C) 1995, 1996 Olaf Kirch <[email protected]>
7  * Copyright (C) 1999, Trond Myklebust <[email protected]>
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 #define NLMDBG_FACILITY NLMDBG_XDR
21 
22 static inline loff_t
23 s64_to_loff_t(__s64 offset)
24 {
25  return (loff_t)offset;
26 }
27 
28 
29 static inline s64
30 loff_t_to_s64(loff_t offset)
31 {
32  s64 res;
33  if (offset > NLM4_OFFSET_MAX)
34  res = NLM4_OFFSET_MAX;
35  else if (offset < -NLM4_OFFSET_MAX)
36  res = -NLM4_OFFSET_MAX;
37  else
38  res = offset;
39  return res;
40 }
41 
42 /*
43  * XDR functions for basic NLM types
44  */
45 static __be32 *
46 nlm4_decode_cookie(__be32 *p, struct nlm_cookie *c)
47 {
48  unsigned int len;
49 
50  len = ntohl(*p++);
51 
52  if(len==0)
53  {
54  c->len=4;
55  memset(c->data, 0, 4); /* hockeypux brain damage */
56  }
57  else if(len<=NLM_MAXCOOKIELEN)
58  {
59  c->len=len;
60  memcpy(c->data, p, len);
61  p+=XDR_QUADLEN(len);
62  }
63  else
64  {
65  dprintk("lockd: bad cookie size %d (only cookies under "
66  "%d bytes are supported.)\n",
67  len, NLM_MAXCOOKIELEN);
68  return NULL;
69  }
70  return p;
71 }
72 
73 static __be32 *
74 nlm4_encode_cookie(__be32 *p, struct nlm_cookie *c)
75 {
76  *p++ = htonl(c->len);
77  memcpy(p, c->data, c->len);
78  p+=XDR_QUADLEN(c->len);
79  return p;
80 }
81 
82 static __be32 *
83 nlm4_decode_fh(__be32 *p, struct nfs_fh *f)
84 {
85  memset(f->data, 0, sizeof(f->data));
86  f->size = ntohl(*p++);
87  if (f->size > NFS_MAXFHSIZE) {
88  dprintk("lockd: bad fhandle size %d (should be <=%d)\n",
89  f->size, NFS_MAXFHSIZE);
90  return NULL;
91  }
92  memcpy(f->data, p, f->size);
93  return p + XDR_QUADLEN(f->size);
94 }
95 
96 /*
97  * Encode and decode owner handle
98  */
99 static __be32 *
100 nlm4_decode_oh(__be32 *p, struct xdr_netobj *oh)
101 {
102  return xdr_decode_netobj(p, oh);
103 }
104 
105 static __be32 *
106 nlm4_decode_lock(__be32 *p, struct nlm_lock *lock)
107 {
108  struct file_lock *fl = &lock->fl;
109  __u64 len, start;
110  __s64 end;
111 
112  if (!(p = xdr_decode_string_inplace(p, &lock->caller,
113  &lock->len, NLM_MAXSTRLEN))
114  || !(p = nlm4_decode_fh(p, &lock->fh))
115  || !(p = nlm4_decode_oh(p, &lock->oh)))
116  return NULL;
117  lock->svid = ntohl(*p++);
118 
119  locks_init_lock(fl);
120  fl->fl_owner = current->files;
121  fl->fl_pid = (pid_t)lock->svid;
122  fl->fl_flags = FL_POSIX;
123  fl->fl_type = F_RDLCK; /* as good as anything else */
124  p = xdr_decode_hyper(p, &start);
125  p = xdr_decode_hyper(p, &len);
126  end = start + len - 1;
127 
128  fl->fl_start = s64_to_loff_t(start);
129 
130  if (len == 0 || end < 0)
131  fl->fl_end = OFFSET_MAX;
132  else
133  fl->fl_end = s64_to_loff_t(end);
134  return p;
135 }
136 
137 /*
138  * Encode result of a TEST/TEST_MSG call
139  */
140 static __be32 *
141 nlm4_encode_testres(__be32 *p, struct nlm_res *resp)
142 {
143  s64 start, len;
144 
145  dprintk("xdr: before encode_testres (p %p resp %p)\n", p, resp);
146  if (!(p = nlm4_encode_cookie(p, &resp->cookie)))
147  return NULL;
148  *p++ = resp->status;
149 
150  if (resp->status == nlm_lck_denied) {
151  struct file_lock *fl = &resp->lock.fl;
152 
153  *p++ = (fl->fl_type == F_RDLCK)? xdr_zero : xdr_one;
154  *p++ = htonl(resp->lock.svid);
155 
156  /* Encode owner handle. */
157  if (!(p = xdr_encode_netobj(p, &resp->lock.oh)))
158  return NULL;
159 
160  start = loff_t_to_s64(fl->fl_start);
161  if (fl->fl_end == OFFSET_MAX)
162  len = 0;
163  else
164  len = loff_t_to_s64(fl->fl_end - fl->fl_start + 1);
165 
166  p = xdr_encode_hyper(p, start);
167  p = xdr_encode_hyper(p, len);
168  dprintk("xdr: encode_testres (status %u pid %d type %d start %Ld end %Ld)\n",
169  resp->status, (int)resp->lock.svid, fl->fl_type,
170  (long long)fl->fl_start, (long long)fl->fl_end);
171  }
172 
173  dprintk("xdr: after encode_testres (p %p resp %p)\n", p, resp);
174  return p;
175 }
176 
177 
178 /*
179  * First, the server side XDR functions
180  */
181 int
183 {
184  u32 exclusive;
185 
186  if (!(p = nlm4_decode_cookie(p, &argp->cookie)))
187  return 0;
188 
189  exclusive = ntohl(*p++);
190  if (!(p = nlm4_decode_lock(p, &argp->lock)))
191  return 0;
192  if (exclusive)
193  argp->lock.fl.fl_type = F_WRLCK;
194 
195  return xdr_argsize_check(rqstp, p);
196 }
197 
198 int
199 nlm4svc_encode_testres(struct svc_rqst *rqstp, __be32 *p, struct nlm_res *resp)
200 {
201  if (!(p = nlm4_encode_testres(p, resp)))
202  return 0;
203  return xdr_ressize_check(rqstp, p);
204 }
205 
206 int
208 {
209  u32 exclusive;
210 
211  if (!(p = nlm4_decode_cookie(p, &argp->cookie)))
212  return 0;
213  argp->block = ntohl(*p++);
214  exclusive = ntohl(*p++);
215  if (!(p = nlm4_decode_lock(p, &argp->lock)))
216  return 0;
217  if (exclusive)
218  argp->lock.fl.fl_type = F_WRLCK;
219  argp->reclaim = ntohl(*p++);
220  argp->state = ntohl(*p++);
221  argp->monitor = 1; /* monitor client by default */
222 
223  return xdr_argsize_check(rqstp, p);
224 }
225 
226 int
228 {
229  u32 exclusive;
230 
231  if (!(p = nlm4_decode_cookie(p, &argp->cookie)))
232  return 0;
233  argp->block = ntohl(*p++);
234  exclusive = ntohl(*p++);
235  if (!(p = nlm4_decode_lock(p, &argp->lock)))
236  return 0;
237  if (exclusive)
238  argp->lock.fl.fl_type = F_WRLCK;
239  return xdr_argsize_check(rqstp, p);
240 }
241 
242 int
244 {
245  if (!(p = nlm4_decode_cookie(p, &argp->cookie))
246  || !(p = nlm4_decode_lock(p, &argp->lock)))
247  return 0;
248  argp->lock.fl.fl_type = F_UNLCK;
249  return xdr_argsize_check(rqstp, p);
250 }
251 
252 int
254 {
255  struct nlm_lock *lock = &argp->lock;
256 
257  memset(lock, 0, sizeof(*lock));
258  locks_init_lock(&lock->fl);
259  lock->svid = ~(u32) 0;
260  lock->fl.fl_pid = (pid_t)lock->svid;
261 
262  if (!(p = nlm4_decode_cookie(p, &argp->cookie))
263  || !(p = xdr_decode_string_inplace(p, &lock->caller,
264  &lock->len, NLM_MAXSTRLEN))
265  || !(p = nlm4_decode_fh(p, &lock->fh))
266  || !(p = nlm4_decode_oh(p, &lock->oh)))
267  return 0;
268  argp->fsm_mode = ntohl(*p++);
269  argp->fsm_access = ntohl(*p++);
270  return xdr_argsize_check(rqstp, p);
271 }
272 
273 int
274 nlm4svc_encode_shareres(struct svc_rqst *rqstp, __be32 *p, struct nlm_res *resp)
275 {
276  if (!(p = nlm4_encode_cookie(p, &resp->cookie)))
277  return 0;
278  *p++ = resp->status;
279  *p++ = xdr_zero; /* sequence argument */
280  return xdr_ressize_check(rqstp, p);
281 }
282 
283 int
284 nlm4svc_encode_res(struct svc_rqst *rqstp, __be32 *p, struct nlm_res *resp)
285 {
286  if (!(p = nlm4_encode_cookie(p, &resp->cookie)))
287  return 0;
288  *p++ = resp->status;
289  return xdr_ressize_check(rqstp, p);
290 }
291 
292 int
293 nlm4svc_decode_notify(struct svc_rqst *rqstp, __be32 *p, struct nlm_args *argp)
294 {
295  struct nlm_lock *lock = &argp->lock;
296 
297  if (!(p = xdr_decode_string_inplace(p, &lock->caller,
298  &lock->len, NLM_MAXSTRLEN)))
299  return 0;
300  argp->state = ntohl(*p++);
301  return xdr_argsize_check(rqstp, p);
302 }
303 
304 int
306 {
307  if (!(p = xdr_decode_string_inplace(p, &argp->mon, &argp->len, SM_MAXSTRLEN)))
308  return 0;
309  argp->state = ntohl(*p++);
310  memcpy(&argp->priv.data, p, sizeof(argp->priv.data));
311  p += XDR_QUADLEN(SM_PRIV_SIZE);
312  return xdr_argsize_check(rqstp, p);
313 }
314 
315 int
316 nlm4svc_decode_res(struct svc_rqst *rqstp, __be32 *p, struct nlm_res *resp)
317 {
318  if (!(p = nlm4_decode_cookie(p, &resp->cookie)))
319  return 0;
320  resp->status = *p++;
321  return xdr_argsize_check(rqstp, p);
322 }
323 
324 int
325 nlm4svc_decode_void(struct svc_rqst *rqstp, __be32 *p, void *dummy)
326 {
327  return xdr_argsize_check(rqstp, p);
328 }
329 
330 int
331 nlm4svc_encode_void(struct svc_rqst *rqstp, __be32 *p, void *dummy)
332 {
333  return xdr_ressize_check(rqstp, p);
334 }