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 | #include "svcxdr.h" |
23 | |
24 | |
25 | static inline loff_t |
26 | s32_to_loff_t(__s32 offset) |
27 | { |
28 | return (loff_t)offset; |
29 | } |
30 | |
31 | static inline __s32 |
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 | * NLM file handles are defined by specification to be a variable-length |
46 | * XDR opaque no longer than 1024 bytes. However, this implementation |
47 | * constrains their length to exactly the length of an NFSv2 file |
48 | * handle. |
49 | */ |
50 | static bool |
51 | svcxdr_decode_fhandle(struct xdr_stream *xdr, struct nfs_fh *fh) |
52 | { |
53 | __be32 *p; |
54 | u32 len; |
55 | |
56 | if (xdr_stream_decode_u32(xdr, ptr: &len) < 0) |
57 | return false; |
58 | if (len != NFS2_FHSIZE) |
59 | return false; |
60 | |
61 | p = xdr_inline_decode(xdr, nbytes: len); |
62 | if (!p) |
63 | return false; |
64 | fh->size = NFS2_FHSIZE; |
65 | memcpy(fh->data, p, len); |
66 | memset(fh->data + NFS2_FHSIZE, 0, sizeof(fh->data) - NFS2_FHSIZE); |
67 | |
68 | return true; |
69 | } |
70 | |
71 | static bool |
72 | svcxdr_decode_lock(struct xdr_stream *xdr, struct nlm_lock *lock) |
73 | { |
74 | struct file_lock *fl = &lock->fl; |
75 | s32 start, len, end; |
76 | |
77 | if (!svcxdr_decode_string(xdr, data: &lock->caller, data_len: &lock->len)) |
78 | return false; |
79 | if (!svcxdr_decode_fhandle(xdr, fh: &lock->fh)) |
80 | return false; |
81 | if (!svcxdr_decode_owner(xdr, obj: &lock->oh)) |
82 | return false; |
83 | if (xdr_stream_decode_u32(xdr, ptr: &lock->svid) < 0) |
84 | return false; |
85 | if (xdr_stream_decode_u32(xdr, ptr: &start) < 0) |
86 | return false; |
87 | if (xdr_stream_decode_u32(xdr, ptr: &len) < 0) |
88 | return false; |
89 | |
90 | locks_init_lock(fl); |
91 | fl->c.flc_flags = FL_POSIX; |
92 | fl->c.flc_type = F_RDLCK; |
93 | end = start + len - 1; |
94 | fl->fl_start = s32_to_loff_t(offset: start); |
95 | if (len == 0 || end < 0) |
96 | fl->fl_end = OFFSET_MAX; |
97 | else |
98 | fl->fl_end = s32_to_loff_t(offset: end); |
99 | |
100 | return true; |
101 | } |
102 | |
103 | static bool |
104 | svcxdr_encode_holder(struct xdr_stream *xdr, const struct nlm_lock *lock) |
105 | { |
106 | const struct file_lock *fl = &lock->fl; |
107 | s32 start, len; |
108 | |
109 | /* exclusive */ |
110 | if (xdr_stream_encode_bool(xdr, n: fl->c.flc_type != F_RDLCK) < 0) |
111 | return false; |
112 | if (xdr_stream_encode_u32(xdr, n: lock->svid) < 0) |
113 | return false; |
114 | if (!svcxdr_encode_owner(xdr, obj: &lock->oh)) |
115 | return false; |
116 | start = loff_t_to_s32(offset: fl->fl_start); |
117 | if (fl->fl_end == OFFSET_MAX) |
118 | len = 0; |
119 | else |
120 | len = loff_t_to_s32(offset: fl->fl_end - fl->fl_start + 1); |
121 | if (xdr_stream_encode_u32(xdr, n: start) < 0) |
122 | return false; |
123 | if (xdr_stream_encode_u32(xdr, n: len) < 0) |
124 | return false; |
125 | |
126 | return true; |
127 | } |
128 | |
129 | static bool |
130 | svcxdr_encode_testrply(struct xdr_stream *xdr, const struct nlm_res *resp) |
131 | { |
132 | if (!svcxdr_encode_stats(xdr, status: resp->status)) |
133 | return false; |
134 | switch (resp->status) { |
135 | case nlm_lck_denied: |
136 | if (!svcxdr_encode_holder(xdr, lock: &resp->lock)) |
137 | return false; |
138 | } |
139 | |
140 | return true; |
141 | } |
142 | |
143 | |
144 | /* |
145 | * Decode Call arguments |
146 | */ |
147 | |
148 | bool |
149 | nlmsvc_decode_void(struct svc_rqst *rqstp, struct xdr_stream *xdr) |
150 | { |
151 | return true; |
152 | } |
153 | |
154 | bool |
155 | nlmsvc_decode_testargs(struct svc_rqst *rqstp, struct xdr_stream *xdr) |
156 | { |
157 | struct nlm_args *argp = rqstp->rq_argp; |
158 | u32 exclusive; |
159 | |
160 | if (!svcxdr_decode_cookie(xdr, cookie: &argp->cookie)) |
161 | return false; |
162 | if (xdr_stream_decode_bool(xdr, ptr: &exclusive) < 0) |
163 | return false; |
164 | if (!svcxdr_decode_lock(xdr, lock: &argp->lock)) |
165 | return false; |
166 | if (exclusive) |
167 | argp->lock.fl.c.flc_type = F_WRLCK; |
168 | |
169 | return true; |
170 | } |
171 | |
172 | bool |
173 | nlmsvc_decode_lockargs(struct svc_rqst *rqstp, struct xdr_stream *xdr) |
174 | { |
175 | struct nlm_args *argp = rqstp->rq_argp; |
176 | u32 exclusive; |
177 | |
178 | if (!svcxdr_decode_cookie(xdr, cookie: &argp->cookie)) |
179 | return false; |
180 | if (xdr_stream_decode_bool(xdr, ptr: &argp->block) < 0) |
181 | return false; |
182 | if (xdr_stream_decode_bool(xdr, ptr: &exclusive) < 0) |
183 | return false; |
184 | if (!svcxdr_decode_lock(xdr, lock: &argp->lock)) |
185 | return false; |
186 | if (exclusive) |
187 | argp->lock.fl.c.flc_type = F_WRLCK; |
188 | if (xdr_stream_decode_bool(xdr, ptr: &argp->reclaim) < 0) |
189 | return false; |
190 | if (xdr_stream_decode_u32(xdr, ptr: &argp->state) < 0) |
191 | return false; |
192 | argp->monitor = 1; /* monitor client by default */ |
193 | |
194 | return true; |
195 | } |
196 | |
197 | bool |
198 | nlmsvc_decode_cancargs(struct svc_rqst *rqstp, struct xdr_stream *xdr) |
199 | { |
200 | struct nlm_args *argp = rqstp->rq_argp; |
201 | u32 exclusive; |
202 | |
203 | if (!svcxdr_decode_cookie(xdr, cookie: &argp->cookie)) |
204 | return false; |
205 | if (xdr_stream_decode_bool(xdr, ptr: &argp->block) < 0) |
206 | return false; |
207 | if (xdr_stream_decode_bool(xdr, ptr: &exclusive) < 0) |
208 | return false; |
209 | if (!svcxdr_decode_lock(xdr, lock: &argp->lock)) |
210 | return false; |
211 | if (exclusive) |
212 | argp->lock.fl.c.flc_type = F_WRLCK; |
213 | |
214 | return true; |
215 | } |
216 | |
217 | bool |
218 | nlmsvc_decode_unlockargs(struct svc_rqst *rqstp, struct xdr_stream *xdr) |
219 | { |
220 | struct nlm_args *argp = rqstp->rq_argp; |
221 | |
222 | if (!svcxdr_decode_cookie(xdr, cookie: &argp->cookie)) |
223 | return false; |
224 | if (!svcxdr_decode_lock(xdr, lock: &argp->lock)) |
225 | return false; |
226 | argp->lock.fl.c.flc_type = F_UNLCK; |
227 | |
228 | return true; |
229 | } |
230 | |
231 | bool |
232 | nlmsvc_decode_res(struct svc_rqst *rqstp, struct xdr_stream *xdr) |
233 | { |
234 | struct nlm_res *resp = rqstp->rq_argp; |
235 | |
236 | if (!svcxdr_decode_cookie(xdr, cookie: &resp->cookie)) |
237 | return false; |
238 | if (!svcxdr_decode_stats(xdr, status: &resp->status)) |
239 | return false; |
240 | |
241 | return true; |
242 | } |
243 | |
244 | bool |
245 | nlmsvc_decode_reboot(struct svc_rqst *rqstp, struct xdr_stream *xdr) |
246 | { |
247 | struct nlm_reboot *argp = rqstp->rq_argp; |
248 | __be32 *p; |
249 | u32 len; |
250 | |
251 | if (xdr_stream_decode_u32(xdr, ptr: &len) < 0) |
252 | return false; |
253 | if (len > SM_MAXSTRLEN) |
254 | return false; |
255 | p = xdr_inline_decode(xdr, nbytes: len); |
256 | if (!p) |
257 | return false; |
258 | argp->len = len; |
259 | argp->mon = (char *)p; |
260 | if (xdr_stream_decode_u32(xdr, ptr: &argp->state) < 0) |
261 | return false; |
262 | p = xdr_inline_decode(xdr, SM_PRIV_SIZE); |
263 | if (!p) |
264 | return false; |
265 | memcpy(&argp->priv.data, p, sizeof(argp->priv.data)); |
266 | |
267 | return true; |
268 | } |
269 | |
270 | bool |
271 | nlmsvc_decode_shareargs(struct svc_rqst *rqstp, struct xdr_stream *xdr) |
272 | { |
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, cookie: &argp->cookie)) |
281 | return false; |
282 | if (!svcxdr_decode_string(xdr, data: &lock->caller, data_len: &lock->len)) |
283 | return false; |
284 | if (!svcxdr_decode_fhandle(xdr, fh: &lock->fh)) |
285 | return false; |
286 | if (!svcxdr_decode_owner(xdr, obj: &lock->oh)) |
287 | return false; |
288 | /* XXX: Range checks are missing in the original code */ |
289 | if (xdr_stream_decode_u32(xdr, ptr: &argp->fsm_mode) < 0) |
290 | return false; |
291 | if (xdr_stream_decode_u32(xdr, ptr: &argp->fsm_access) < 0) |
292 | return false; |
293 | |
294 | return true; |
295 | } |
296 | |
297 | bool |
298 | nlmsvc_decode_notify(struct svc_rqst *rqstp, struct xdr_stream *xdr) |
299 | { |
300 | struct nlm_args *argp = rqstp->rq_argp; |
301 | struct nlm_lock *lock = &argp->lock; |
302 | |
303 | if (!svcxdr_decode_string(xdr, data: &lock->caller, data_len: &lock->len)) |
304 | return false; |
305 | if (xdr_stream_decode_u32(xdr, ptr: &argp->state) < 0) |
306 | return false; |
307 | |
308 | return true; |
309 | } |
310 | |
311 | |
312 | /* |
313 | * Encode Reply results |
314 | */ |
315 | |
316 | bool |
317 | nlmsvc_encode_void(struct svc_rqst *rqstp, struct xdr_stream *xdr) |
318 | { |
319 | return true; |
320 | } |
321 | |
322 | bool |
323 | nlmsvc_encode_testres(struct svc_rqst *rqstp, struct xdr_stream *xdr) |
324 | { |
325 | struct nlm_res *resp = rqstp->rq_resp; |
326 | |
327 | return svcxdr_encode_cookie(xdr, cookie: &resp->cookie) && |
328 | svcxdr_encode_testrply(xdr, resp); |
329 | } |
330 | |
331 | bool |
332 | nlmsvc_encode_res(struct svc_rqst *rqstp, struct xdr_stream *xdr) |
333 | { |
334 | struct nlm_res *resp = rqstp->rq_resp; |
335 | |
336 | return svcxdr_encode_cookie(xdr, cookie: &resp->cookie) && |
337 | svcxdr_encode_stats(xdr, status: resp->status); |
338 | } |
339 | |
340 | bool |
341 | nlmsvc_encode_shareres(struct svc_rqst *rqstp, struct xdr_stream *xdr) |
342 | { |
343 | struct nlm_res *resp = rqstp->rq_resp; |
344 | |
345 | if (!svcxdr_encode_cookie(xdr, cookie: &resp->cookie)) |
346 | return false; |
347 | if (!svcxdr_encode_stats(xdr, status: resp->status)) |
348 | return false; |
349 | /* sequence */ |
350 | if (xdr_stream_encode_u32(xdr, n: 0) < 0) |
351 | return false; |
352 | |
353 | return true; |
354 | } |
355 | |