1 /*
2 * XDR support for nfsd
3 *
4 * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
5 */
6
7 #include "xdr.h"
8 #include "auth.h"
9
10 #define NFSDDBG_FACILITY NFSDDBG_XDR
11
12 /*
13 * Mapping of S_IF* types to NFS file types
14 */
15 static u32 nfs_ftypes[] = {
16 NFNON, NFCHR, NFCHR, NFBAD,
17 NFDIR, NFBAD, NFBLK, NFBAD,
18 NFREG, NFBAD, NFLNK, NFBAD,
19 NFSOCK, NFBAD, NFLNK, NFBAD,
20 };
21
22
23 /*
24 * XDR functions for basic NFS types
25 */
26 static __be32 *
decode_fh(__be32 * p,struct svc_fh * fhp)27 decode_fh(__be32 *p, struct svc_fh *fhp)
28 {
29 fh_init(fhp, NFS_FHSIZE);
30 memcpy(&fhp->fh_handle.fh_base, p, NFS_FHSIZE);
31 fhp->fh_handle.fh_size = NFS_FHSIZE;
32
33 /* FIXME: Look up export pointer here and verify
34 * Sun Secure RPC if requested */
35 return p + (NFS_FHSIZE >> 2);
36 }
37
38 /* Helper function for NFSv2 ACL code */
nfs2svc_decode_fh(__be32 * p,struct svc_fh * fhp)39 __be32 *nfs2svc_decode_fh(__be32 *p, struct svc_fh *fhp)
40 {
41 return decode_fh(p, fhp);
42 }
43
44 static __be32 *
encode_fh(__be32 * p,struct svc_fh * fhp)45 encode_fh(__be32 *p, struct svc_fh *fhp)
46 {
47 memcpy(p, &fhp->fh_handle.fh_base, NFS_FHSIZE);
48 return p + (NFS_FHSIZE>> 2);
49 }
50
51 /*
52 * Decode a file name and make sure that the path contains
53 * no slashes or null bytes.
54 */
55 static __be32 *
decode_filename(__be32 * p,char ** namp,unsigned int * lenp)56 decode_filename(__be32 *p, char **namp, unsigned int *lenp)
57 {
58 char *name;
59 unsigned int i;
60
61 if ((p = xdr_decode_string_inplace(p, namp, lenp, NFS_MAXNAMLEN)) != NULL) {
62 for (i = 0, name = *namp; i < *lenp; i++, name++) {
63 if (*name == '\0' || *name == '/')
64 return NULL;
65 }
66 }
67
68 return p;
69 }
70
71 static __be32 *
decode_pathname(__be32 * p,char ** namp,unsigned int * lenp)72 decode_pathname(__be32 *p, char **namp, unsigned int *lenp)
73 {
74 char *name;
75 unsigned int i;
76
77 if ((p = xdr_decode_string_inplace(p, namp, lenp, NFS_MAXPATHLEN)) != NULL) {
78 for (i = 0, name = *namp; i < *lenp; i++, name++) {
79 if (*name == '\0')
80 return NULL;
81 }
82 }
83
84 return p;
85 }
86
87 static __be32 *
decode_sattr(__be32 * p,struct iattr * iap)88 decode_sattr(__be32 *p, struct iattr *iap)
89 {
90 u32 tmp, tmp1;
91
92 iap->ia_valid = 0;
93
94 /* Sun client bug compatibility check: some sun clients seem to
95 * put 0xffff in the mode field when they mean 0xffffffff.
96 * Quoting the 4.4BSD nfs server code: Nah nah nah nah na nah.
97 */
98 if ((tmp = ntohl(*p++)) != (u32)-1 && tmp != 0xffff) {
99 iap->ia_valid |= ATTR_MODE;
100 iap->ia_mode = tmp;
101 }
102 if ((tmp = ntohl(*p++)) != (u32)-1) {
103 iap->ia_valid |= ATTR_UID;
104 iap->ia_uid = tmp;
105 }
106 if ((tmp = ntohl(*p++)) != (u32)-1) {
107 iap->ia_valid |= ATTR_GID;
108 iap->ia_gid = tmp;
109 }
110 if ((tmp = ntohl(*p++)) != (u32)-1) {
111 iap->ia_valid |= ATTR_SIZE;
112 iap->ia_size = tmp;
113 }
114 tmp = ntohl(*p++); tmp1 = ntohl(*p++);
115 if (tmp != (u32)-1 && tmp1 != (u32)-1) {
116 iap->ia_valid |= ATTR_ATIME | ATTR_ATIME_SET;
117 iap->ia_atime.tv_sec = tmp;
118 iap->ia_atime.tv_nsec = tmp1 * 1000;
119 }
120 tmp = ntohl(*p++); tmp1 = ntohl(*p++);
121 if (tmp != (u32)-1 && tmp1 != (u32)-1) {
122 iap->ia_valid |= ATTR_MTIME | ATTR_MTIME_SET;
123 iap->ia_mtime.tv_sec = tmp;
124 iap->ia_mtime.tv_nsec = tmp1 * 1000;
125 /*
126 * Passing the invalid value useconds=1000000 for mtime
127 * is a Sun convention for "set both mtime and atime to
128 * current server time". It's needed to make permissions
129 * checks for the "touch" program across v2 mounts to
130 * Solaris and Irix boxes work correctly. See description of
131 * sattr in section 6.1 of "NFS Illustrated" by
132 * Brent Callaghan, Addison-Wesley, ISBN 0-201-32750-5
133 */
134 if (tmp1 == 1000000)
135 iap->ia_valid &= ~(ATTR_ATIME_SET|ATTR_MTIME_SET);
136 }
137 return p;
138 }
139
140 static __be32 *
encode_fattr(struct svc_rqst * rqstp,__be32 * p,struct svc_fh * fhp,struct kstat * stat)141 encode_fattr(struct svc_rqst *rqstp, __be32 *p, struct svc_fh *fhp,
142 struct kstat *stat)
143 {
144 struct dentry *dentry = fhp->fh_dentry;
145 int type;
146 struct timespec time;
147 u32 f;
148
149 type = (stat->mode & S_IFMT);
150
151 *p++ = htonl(nfs_ftypes[type >> 12]);
152 *p++ = htonl((u32) stat->mode);
153 *p++ = htonl((u32) stat->nlink);
154 *p++ = htonl((u32) nfsd_ruid(rqstp, stat->uid));
155 *p++ = htonl((u32) nfsd_rgid(rqstp, stat->gid));
156
157 if (S_ISLNK(type) && stat->size > NFS_MAXPATHLEN) {
158 *p++ = htonl(NFS_MAXPATHLEN);
159 } else {
160 *p++ = htonl((u32) stat->size);
161 }
162 *p++ = htonl((u32) stat->blksize);
163 if (S_ISCHR(type) || S_ISBLK(type))
164 *p++ = htonl(new_encode_dev(stat->rdev));
165 else
166 *p++ = htonl(0xffffffff);
167 *p++ = htonl((u32) stat->blocks);
168 switch (fsid_source(fhp)) {
169 default:
170 case FSIDSOURCE_DEV:
171 *p++ = htonl(new_encode_dev(stat->dev));
172 break;
173 case FSIDSOURCE_FSID:
174 *p++ = htonl((u32) fhp->fh_export->ex_fsid);
175 break;
176 case FSIDSOURCE_UUID:
177 f = ((u32*)fhp->fh_export->ex_uuid)[0];
178 f ^= ((u32*)fhp->fh_export->ex_uuid)[1];
179 f ^= ((u32*)fhp->fh_export->ex_uuid)[2];
180 f ^= ((u32*)fhp->fh_export->ex_uuid)[3];
181 *p++ = htonl(f);
182 break;
183 }
184 *p++ = htonl((u32) stat->ino);
185 *p++ = htonl((u32) stat->atime.tv_sec);
186 *p++ = htonl(stat->atime.tv_nsec ? stat->atime.tv_nsec / 1000 : 0);
187 lease_get_mtime(dentry->d_inode, &time);
188 *p++ = htonl((u32) time.tv_sec);
189 *p++ = htonl(time.tv_nsec ? time.tv_nsec / 1000 : 0);
190 *p++ = htonl((u32) stat->ctime.tv_sec);
191 *p++ = htonl(stat->ctime.tv_nsec ? stat->ctime.tv_nsec / 1000 : 0);
192
193 return p;
194 }
195
196 /* Helper function for NFSv2 ACL code */
nfs2svc_encode_fattr(struct svc_rqst * rqstp,__be32 * p,struct svc_fh * fhp)197 __be32 *nfs2svc_encode_fattr(struct svc_rqst *rqstp, __be32 *p, struct svc_fh *fhp)
198 {
199 struct kstat stat;
200 vfs_getattr(fhp->fh_export->ex_path.mnt, fhp->fh_dentry, &stat);
201 return encode_fattr(rqstp, p, fhp, &stat);
202 }
203
204 /*
205 * XDR decode functions
206 */
207 int
nfssvc_decode_void(struct svc_rqst * rqstp,__be32 * p,void * dummy)208 nfssvc_decode_void(struct svc_rqst *rqstp, __be32 *p, void *dummy)
209 {
210 return xdr_argsize_check(rqstp, p);
211 }
212
213 int
nfssvc_decode_fhandle(struct svc_rqst * rqstp,__be32 * p,struct nfsd_fhandle * args)214 nfssvc_decode_fhandle(struct svc_rqst *rqstp, __be32 *p, struct nfsd_fhandle *args)
215 {
216 if (!(p = decode_fh(p, &args->fh)))
217 return 0;
218 return xdr_argsize_check(rqstp, p);
219 }
220
221 int
nfssvc_decode_sattrargs(struct svc_rqst * rqstp,__be32 * p,struct nfsd_sattrargs * args)222 nfssvc_decode_sattrargs(struct svc_rqst *rqstp, __be32 *p,
223 struct nfsd_sattrargs *args)
224 {
225 p = decode_fh(p, &args->fh);
226 if (!p)
227 return 0;
228 p = decode_sattr(p, &args->attrs);
229
230 return xdr_argsize_check(rqstp, p);
231 }
232
233 int
nfssvc_decode_diropargs(struct svc_rqst * rqstp,__be32 * p,struct nfsd_diropargs * args)234 nfssvc_decode_diropargs(struct svc_rqst *rqstp, __be32 *p,
235 struct nfsd_diropargs *args)
236 {
237 if (!(p = decode_fh(p, &args->fh))
238 || !(p = decode_filename(p, &args->name, &args->len)))
239 return 0;
240
241 return xdr_argsize_check(rqstp, p);
242 }
243
244 int
nfssvc_decode_readargs(struct svc_rqst * rqstp,__be32 * p,struct nfsd_readargs * args)245 nfssvc_decode_readargs(struct svc_rqst *rqstp, __be32 *p,
246 struct nfsd_readargs *args)
247 {
248 unsigned int len;
249 int v,pn;
250 if (!(p = decode_fh(p, &args->fh)))
251 return 0;
252
253 args->offset = ntohl(*p++);
254 len = args->count = ntohl(*p++);
255 p++; /* totalcount - unused */
256
257 if (len > NFSSVC_MAXBLKSIZE_V2)
258 len = NFSSVC_MAXBLKSIZE_V2;
259
260 /* set up somewhere to store response.
261 * We take pages, put them on reslist and include in iovec
262 */
263 v=0;
264 while (len > 0) {
265 pn = rqstp->rq_resused++;
266 rqstp->rq_vec[v].iov_base = page_address(rqstp->rq_respages[pn]);
267 rqstp->rq_vec[v].iov_len = len < PAGE_SIZE?len:PAGE_SIZE;
268 len -= rqstp->rq_vec[v].iov_len;
269 v++;
270 }
271 args->vlen = v;
272 return xdr_argsize_check(rqstp, p);
273 }
274
275 int
nfssvc_decode_writeargs(struct svc_rqst * rqstp,__be32 * p,struct nfsd_writeargs * args)276 nfssvc_decode_writeargs(struct svc_rqst *rqstp, __be32 *p,
277 struct nfsd_writeargs *args)
278 {
279 unsigned int len, hdr, dlen;
280 int v;
281
282 if (!(p = decode_fh(p, &args->fh)))
283 return 0;
284
285 p++; /* beginoffset */
286 args->offset = ntohl(*p++); /* offset */
287 p++; /* totalcount */
288 len = args->len = ntohl(*p++);
289 /*
290 * The protocol specifies a maximum of 8192 bytes.
291 */
292 if (len > NFSSVC_MAXBLKSIZE_V2)
293 return 0;
294
295 /*
296 * Check to make sure that we got the right number of
297 * bytes.
298 */
299 hdr = (void*)p - rqstp->rq_arg.head[0].iov_base;
300 dlen = rqstp->rq_arg.head[0].iov_len + rqstp->rq_arg.page_len
301 - hdr;
302
303 /*
304 * Round the length of the data which was specified up to
305 * the next multiple of XDR units and then compare that
306 * against the length which was actually received.
307 * Note that when RPCSEC/GSS (for example) is used, the
308 * data buffer can be padded so dlen might be larger
309 * than required. It must never be smaller.
310 */
311 if (dlen < XDR_QUADLEN(len)*4)
312 return 0;
313
314 rqstp->rq_vec[0].iov_base = (void*)p;
315 rqstp->rq_vec[0].iov_len = rqstp->rq_arg.head[0].iov_len - hdr;
316 v = 0;
317 while (len > rqstp->rq_vec[v].iov_len) {
318 len -= rqstp->rq_vec[v].iov_len;
319 v++;
320 rqstp->rq_vec[v].iov_base = page_address(rqstp->rq_pages[v]);
321 rqstp->rq_vec[v].iov_len = PAGE_SIZE;
322 }
323 rqstp->rq_vec[v].iov_len = len;
324 args->vlen = v + 1;
325 return 1;
326 }
327
328 int
nfssvc_decode_createargs(struct svc_rqst * rqstp,__be32 * p,struct nfsd_createargs * args)329 nfssvc_decode_createargs(struct svc_rqst *rqstp, __be32 *p,
330 struct nfsd_createargs *args)
331 {
332 if ( !(p = decode_fh(p, &args->fh))
333 || !(p = decode_filename(p, &args->name, &args->len)))
334 return 0;
335 p = decode_sattr(p, &args->attrs);
336
337 return xdr_argsize_check(rqstp, p);
338 }
339
340 int
nfssvc_decode_renameargs(struct svc_rqst * rqstp,__be32 * p,struct nfsd_renameargs * args)341 nfssvc_decode_renameargs(struct svc_rqst *rqstp, __be32 *p,
342 struct nfsd_renameargs *args)
343 {
344 if (!(p = decode_fh(p, &args->ffh))
345 || !(p = decode_filename(p, &args->fname, &args->flen))
346 || !(p = decode_fh(p, &args->tfh))
347 || !(p = decode_filename(p, &args->tname, &args->tlen)))
348 return 0;
349
350 return xdr_argsize_check(rqstp, p);
351 }
352
353 int
nfssvc_decode_readlinkargs(struct svc_rqst * rqstp,__be32 * p,struct nfsd_readlinkargs * args)354 nfssvc_decode_readlinkargs(struct svc_rqst *rqstp, __be32 *p, struct nfsd_readlinkargs *args)
355 {
356 if (!(p = decode_fh(p, &args->fh)))
357 return 0;
358 args->buffer = page_address(rqstp->rq_respages[rqstp->rq_resused++]);
359
360 return xdr_argsize_check(rqstp, p);
361 }
362
363 int
nfssvc_decode_linkargs(struct svc_rqst * rqstp,__be32 * p,struct nfsd_linkargs * args)364 nfssvc_decode_linkargs(struct svc_rqst *rqstp, __be32 *p,
365 struct nfsd_linkargs *args)
366 {
367 if (!(p = decode_fh(p, &args->ffh))
368 || !(p = decode_fh(p, &args->tfh))
369 || !(p = decode_filename(p, &args->tname, &args->tlen)))
370 return 0;
371
372 return xdr_argsize_check(rqstp, p);
373 }
374
375 int
nfssvc_decode_symlinkargs(struct svc_rqst * rqstp,__be32 * p,struct nfsd_symlinkargs * args)376 nfssvc_decode_symlinkargs(struct svc_rqst *rqstp, __be32 *p,
377 struct nfsd_symlinkargs *args)
378 {
379 if ( !(p = decode_fh(p, &args->ffh))
380 || !(p = decode_filename(p, &args->fname, &args->flen))
381 || !(p = decode_pathname(p, &args->tname, &args->tlen)))
382 return 0;
383 p = decode_sattr(p, &args->attrs);
384
385 return xdr_argsize_check(rqstp, p);
386 }
387
388 int
nfssvc_decode_readdirargs(struct svc_rqst * rqstp,__be32 * p,struct nfsd_readdirargs * args)389 nfssvc_decode_readdirargs(struct svc_rqst *rqstp, __be32 *p,
390 struct nfsd_readdirargs *args)
391 {
392 if (!(p = decode_fh(p, &args->fh)))
393 return 0;
394 args->cookie = ntohl(*p++);
395 args->count = ntohl(*p++);
396 if (args->count > PAGE_SIZE)
397 args->count = PAGE_SIZE;
398
399 args->buffer = page_address(rqstp->rq_respages[rqstp->rq_resused++]);
400
401 return xdr_argsize_check(rqstp, p);
402 }
403
404 /*
405 * XDR encode functions
406 */
407 int
nfssvc_encode_void(struct svc_rqst * rqstp,__be32 * p,void * dummy)408 nfssvc_encode_void(struct svc_rqst *rqstp, __be32 *p, void *dummy)
409 {
410 return xdr_ressize_check(rqstp, p);
411 }
412
413 int
nfssvc_encode_attrstat(struct svc_rqst * rqstp,__be32 * p,struct nfsd_attrstat * resp)414 nfssvc_encode_attrstat(struct svc_rqst *rqstp, __be32 *p,
415 struct nfsd_attrstat *resp)
416 {
417 p = encode_fattr(rqstp, p, &resp->fh, &resp->stat);
418 return xdr_ressize_check(rqstp, p);
419 }
420
421 int
nfssvc_encode_diropres(struct svc_rqst * rqstp,__be32 * p,struct nfsd_diropres * resp)422 nfssvc_encode_diropres(struct svc_rqst *rqstp, __be32 *p,
423 struct nfsd_diropres *resp)
424 {
425 p = encode_fh(p, &resp->fh);
426 p = encode_fattr(rqstp, p, &resp->fh, &resp->stat);
427 return xdr_ressize_check(rqstp, p);
428 }
429
430 int
nfssvc_encode_readlinkres(struct svc_rqst * rqstp,__be32 * p,struct nfsd_readlinkres * resp)431 nfssvc_encode_readlinkres(struct svc_rqst *rqstp, __be32 *p,
432 struct nfsd_readlinkres *resp)
433 {
434 *p++ = htonl(resp->len);
435 xdr_ressize_check(rqstp, p);
436 rqstp->rq_res.page_len = resp->len;
437 if (resp->len & 3) {
438 /* need to pad the tail */
439 rqstp->rq_res.tail[0].iov_base = p;
440 *p = 0;
441 rqstp->rq_res.tail[0].iov_len = 4 - (resp->len&3);
442 }
443 return 1;
444 }
445
446 int
nfssvc_encode_readres(struct svc_rqst * rqstp,__be32 * p,struct nfsd_readres * resp)447 nfssvc_encode_readres(struct svc_rqst *rqstp, __be32 *p,
448 struct nfsd_readres *resp)
449 {
450 p = encode_fattr(rqstp, p, &resp->fh, &resp->stat);
451 *p++ = htonl(resp->count);
452 xdr_ressize_check(rqstp, p);
453
454 /* now update rqstp->rq_res to reflect data as well */
455 rqstp->rq_res.page_len = resp->count;
456 if (resp->count & 3) {
457 /* need to pad the tail */
458 rqstp->rq_res.tail[0].iov_base = p;
459 *p = 0;
460 rqstp->rq_res.tail[0].iov_len = 4 - (resp->count&3);
461 }
462 return 1;
463 }
464
465 int
nfssvc_encode_readdirres(struct svc_rqst * rqstp,__be32 * p,struct nfsd_readdirres * resp)466 nfssvc_encode_readdirres(struct svc_rqst *rqstp, __be32 *p,
467 struct nfsd_readdirres *resp)
468 {
469 xdr_ressize_check(rqstp, p);
470 p = resp->buffer;
471 *p++ = 0; /* no more entries */
472 *p++ = htonl((resp->common.err == nfserr_eof));
473 rqstp->rq_res.page_len = (((unsigned long)p-1) & ~PAGE_MASK)+1;
474
475 return 1;
476 }
477
478 int
nfssvc_encode_statfsres(struct svc_rqst * rqstp,__be32 * p,struct nfsd_statfsres * resp)479 nfssvc_encode_statfsres(struct svc_rqst *rqstp, __be32 *p,
480 struct nfsd_statfsres *resp)
481 {
482 struct kstatfs *stat = &resp->stats;
483
484 *p++ = htonl(NFSSVC_MAXBLKSIZE_V2); /* max transfer size */
485 *p++ = htonl(stat->f_bsize);
486 *p++ = htonl(stat->f_blocks);
487 *p++ = htonl(stat->f_bfree);
488 *p++ = htonl(stat->f_bavail);
489 return xdr_ressize_check(rqstp, p);
490 }
491
492 int
nfssvc_encode_entry(void * ccdv,const char * name,int namlen,loff_t offset,u64 ino,unsigned int d_type)493 nfssvc_encode_entry(void *ccdv, const char *name,
494 int namlen, loff_t offset, u64 ino, unsigned int d_type)
495 {
496 struct readdir_cd *ccd = ccdv;
497 struct nfsd_readdirres *cd = container_of(ccd, struct nfsd_readdirres, common);
498 __be32 *p = cd->buffer;
499 int buflen, slen;
500
501 /*
502 dprintk("nfsd: entry(%.*s off %ld ino %ld)\n",
503 namlen, name, offset, ino);
504 */
505
506 if (offset > ~((u32) 0)) {
507 cd->common.err = nfserr_fbig;
508 return -EINVAL;
509 }
510 if (cd->offset)
511 *cd->offset = htonl(offset);
512 if (namlen > NFS2_MAXNAMLEN)
513 namlen = NFS2_MAXNAMLEN;/* truncate filename */
514
515 slen = XDR_QUADLEN(namlen);
516 if ((buflen = cd->buflen - slen - 4) < 0) {
517 cd->common.err = nfserr_toosmall;
518 return -EINVAL;
519 }
520 if (ino > ~((u32) 0)) {
521 cd->common.err = nfserr_fbig;
522 return -EINVAL;
523 }
524 *p++ = xdr_one; /* mark entry present */
525 *p++ = htonl((u32) ino); /* file id */
526 p = xdr_encode_array(p, name, namlen);/* name length & name */
527 cd->offset = p; /* remember pointer */
528 *p++ = htonl(~0U); /* offset of next entry */
529
530 cd->buflen = buflen;
531 cd->buffer = p;
532 cd->common.err = nfs_ok;
533 return 0;
534 }
535
536 /*
537 * XDR release functions
538 */
539 int
nfssvc_release_fhandle(struct svc_rqst * rqstp,__be32 * p,struct nfsd_fhandle * resp)540 nfssvc_release_fhandle(struct svc_rqst *rqstp, __be32 *p,
541 struct nfsd_fhandle *resp)
542 {
543 fh_put(&resp->fh);
544 return 1;
545 }
546