1 /* 2 * XDR support for nfsd 3 * 4 * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de> 5 */ 6 7 #include "vfs.h" 8 #include "xdr.h" 9 #include "auth.h" 10 11 #define NFSDDBG_FACILITY NFSDDBG_XDR 12 13 /* 14 * Mapping of S_IF* types to NFS file types 15 */ 16 static u32 nfs_ftypes[] = { 17 NFNON, NFCHR, NFCHR, NFBAD, 18 NFDIR, NFBAD, NFBLK, NFBAD, 19 NFREG, NFBAD, NFLNK, NFBAD, 20 NFSOCK, NFBAD, NFLNK, NFBAD, 21 }; 22 23 24 /* 25 * XDR functions for basic NFS types 26 */ 27 static __be32 * 28 decode_fh(__be32 *p, struct svc_fh *fhp) 29 { 30 fh_init(fhp, NFS_FHSIZE); 31 memcpy(&fhp->fh_handle.fh_base, p, NFS_FHSIZE); 32 fhp->fh_handle.fh_size = NFS_FHSIZE; 33 34 /* FIXME: Look up export pointer here and verify 35 * Sun Secure RPC if requested */ 36 return p + (NFS_FHSIZE >> 2); 37 } 38 39 /* Helper function for NFSv2 ACL code */ 40 __be32 *nfs2svc_decode_fh(__be32 *p, struct svc_fh *fhp) 41 { 42 return decode_fh(p, fhp); 43 } 44 45 static __be32 * 46 encode_fh(__be32 *p, struct svc_fh *fhp) 47 { 48 memcpy(p, &fhp->fh_handle.fh_base, NFS_FHSIZE); 49 return p + (NFS_FHSIZE>> 2); 50 } 51 52 /* 53 * Decode a file name and make sure that the path contains 54 * no slashes or null bytes. 55 */ 56 static __be32 * 57 decode_filename(__be32 *p, char **namp, unsigned int *lenp) 58 { 59 char *name; 60 unsigned int i; 61 62 if ((p = xdr_decode_string_inplace(p, namp, lenp, NFS_MAXNAMLEN)) != NULL) { 63 for (i = 0, name = *namp; i < *lenp; i++, name++) { 64 if (*name == '\0' || *name == '/') 65 return NULL; 66 } 67 } 68 69 return p; 70 } 71 72 static __be32 * 73 decode_pathname(__be32 *p, char **namp, unsigned int *lenp) 74 { 75 char *name; 76 unsigned int i; 77 78 if ((p = xdr_decode_string_inplace(p, namp, lenp, NFS_MAXPATHLEN)) != NULL) { 79 for (i = 0, name = *namp; i < *lenp; i++, name++) { 80 if (*name == '\0') 81 return NULL; 82 } 83 } 84 85 return p; 86 } 87 88 static __be32 * 89 decode_sattr(__be32 *p, struct iattr *iap) 90 { 91 u32 tmp, tmp1; 92 93 iap->ia_valid = 0; 94 95 /* Sun client bug compatibility check: some sun clients seem to 96 * put 0xffff in the mode field when they mean 0xffffffff. 97 * Quoting the 4.4BSD nfs server code: Nah nah nah nah na nah. 98 */ 99 if ((tmp = ntohl(*p++)) != (u32)-1 && tmp != 0xffff) { 100 iap->ia_valid |= ATTR_MODE; 101 iap->ia_mode = tmp; 102 } 103 if ((tmp = ntohl(*p++)) != (u32)-1) { 104 iap->ia_uid = make_kuid(&init_user_ns, tmp); 105 if (uid_valid(iap->ia_uid)) 106 iap->ia_valid |= ATTR_UID; 107 } 108 if ((tmp = ntohl(*p++)) != (u32)-1) { 109 iap->ia_gid = make_kgid(&init_user_ns, tmp); 110 if (gid_valid(iap->ia_gid)) 111 iap->ia_valid |= ATTR_GID; 112 } 113 if ((tmp = ntohl(*p++)) != (u32)-1) { 114 iap->ia_valid |= ATTR_SIZE; 115 iap->ia_size = tmp; 116 } 117 tmp = ntohl(*p++); tmp1 = ntohl(*p++); 118 if (tmp != (u32)-1 && tmp1 != (u32)-1) { 119 iap->ia_valid |= ATTR_ATIME | ATTR_ATIME_SET; 120 iap->ia_atime.tv_sec = tmp; 121 iap->ia_atime.tv_nsec = tmp1 * 1000; 122 } 123 tmp = ntohl(*p++); tmp1 = ntohl(*p++); 124 if (tmp != (u32)-1 && tmp1 != (u32)-1) { 125 iap->ia_valid |= ATTR_MTIME | ATTR_MTIME_SET; 126 iap->ia_mtime.tv_sec = tmp; 127 iap->ia_mtime.tv_nsec = tmp1 * 1000; 128 /* 129 * Passing the invalid value useconds=1000000 for mtime 130 * is a Sun convention for "set both mtime and atime to 131 * current server time". It's needed to make permissions 132 * checks for the "touch" program across v2 mounts to 133 * Solaris and Irix boxes work correctly. See description of 134 * sattr in section 6.1 of "NFS Illustrated" by 135 * Brent Callaghan, Addison-Wesley, ISBN 0-201-32750-5 136 */ 137 if (tmp1 == 1000000) 138 iap->ia_valid &= ~(ATTR_ATIME_SET|ATTR_MTIME_SET); 139 } 140 return p; 141 } 142 143 static __be32 * 144 encode_fattr(struct svc_rqst *rqstp, __be32 *p, struct svc_fh *fhp, 145 struct kstat *stat) 146 { 147 struct dentry *dentry = fhp->fh_dentry; 148 int type; 149 struct timespec time; 150 u32 f; 151 152 type = (stat->mode & S_IFMT); 153 154 *p++ = htonl(nfs_ftypes[type >> 12]); 155 *p++ = htonl((u32) stat->mode); 156 *p++ = htonl((u32) stat->nlink); 157 *p++ = htonl((u32) from_kuid(&init_user_ns, stat->uid)); 158 *p++ = htonl((u32) from_kgid(&init_user_ns, stat->gid)); 159 160 if (S_ISLNK(type) && stat->size > NFS_MAXPATHLEN) { 161 *p++ = htonl(NFS_MAXPATHLEN); 162 } else { 163 *p++ = htonl((u32) stat->size); 164 } 165 *p++ = htonl((u32) stat->blksize); 166 if (S_ISCHR(type) || S_ISBLK(type)) 167 *p++ = htonl(new_encode_dev(stat->rdev)); 168 else 169 *p++ = htonl(0xffffffff); 170 *p++ = htonl((u32) stat->blocks); 171 switch (fsid_source(fhp)) { 172 default: 173 case FSIDSOURCE_DEV: 174 *p++ = htonl(new_encode_dev(stat->dev)); 175 break; 176 case FSIDSOURCE_FSID: 177 *p++ = htonl((u32) fhp->fh_export->ex_fsid); 178 break; 179 case FSIDSOURCE_UUID: 180 f = ((u32*)fhp->fh_export->ex_uuid)[0]; 181 f ^= ((u32*)fhp->fh_export->ex_uuid)[1]; 182 f ^= ((u32*)fhp->fh_export->ex_uuid)[2]; 183 f ^= ((u32*)fhp->fh_export->ex_uuid)[3]; 184 *p++ = htonl(f); 185 break; 186 } 187 *p++ = htonl((u32) stat->ino); 188 *p++ = htonl((u32) stat->atime.tv_sec); 189 *p++ = htonl(stat->atime.tv_nsec ? stat->atime.tv_nsec / 1000 : 0); 190 lease_get_mtime(d_inode(dentry), &time); 191 *p++ = htonl((u32) time.tv_sec); 192 *p++ = htonl(time.tv_nsec ? time.tv_nsec / 1000 : 0); 193 *p++ = htonl((u32) stat->ctime.tv_sec); 194 *p++ = htonl(stat->ctime.tv_nsec ? stat->ctime.tv_nsec / 1000 : 0); 195 196 return p; 197 } 198 199 /* Helper function for NFSv2 ACL code */ 200 __be32 *nfs2svc_encode_fattr(struct svc_rqst *rqstp, __be32 *p, struct svc_fh *fhp, struct kstat *stat) 201 { 202 return encode_fattr(rqstp, p, fhp, stat); 203 } 204 205 /* 206 * XDR decode functions 207 */ 208 int 209 nfssvc_decode_void(struct svc_rqst *rqstp, __be32 *p) 210 { 211 return xdr_argsize_check(rqstp, p); 212 } 213 214 int 215 nfssvc_decode_fhandle(struct svc_rqst *rqstp, __be32 *p) 216 { 217 struct nfsd_fhandle *args = rqstp->rq_argp; 218 219 p = decode_fh(p, &args->fh); 220 if (!p) 221 return 0; 222 return xdr_argsize_check(rqstp, p); 223 } 224 225 int 226 nfssvc_decode_sattrargs(struct svc_rqst *rqstp, __be32 *p) 227 { 228 struct nfsd_sattrargs *args = rqstp->rq_argp; 229 230 p = decode_fh(p, &args->fh); 231 if (!p) 232 return 0; 233 p = decode_sattr(p, &args->attrs); 234 235 return xdr_argsize_check(rqstp, p); 236 } 237 238 int 239 nfssvc_decode_diropargs(struct svc_rqst *rqstp, __be32 *p) 240 { 241 struct nfsd_diropargs *args = rqstp->rq_argp; 242 243 if (!(p = decode_fh(p, &args->fh)) 244 || !(p = decode_filename(p, &args->name, &args->len))) 245 return 0; 246 247 return xdr_argsize_check(rqstp, p); 248 } 249 250 int 251 nfssvc_decode_readargs(struct svc_rqst *rqstp, __be32 *p) 252 { 253 struct nfsd_readargs *args = rqstp->rq_argp; 254 unsigned int len; 255 int v; 256 p = decode_fh(p, &args->fh); 257 if (!p) 258 return 0; 259 260 args->offset = ntohl(*p++); 261 len = args->count = ntohl(*p++); 262 p++; /* totalcount - unused */ 263 264 len = min_t(unsigned int, len, NFSSVC_MAXBLKSIZE_V2); 265 266 /* set up somewhere to store response. 267 * We take pages, put them on reslist and include in iovec 268 */ 269 v=0; 270 while (len > 0) { 271 struct page *p = *(rqstp->rq_next_page++); 272 273 rqstp->rq_vec[v].iov_base = page_address(p); 274 rqstp->rq_vec[v].iov_len = min_t(unsigned int, len, PAGE_SIZE); 275 len -= rqstp->rq_vec[v].iov_len; 276 v++; 277 } 278 args->vlen = v; 279 return xdr_argsize_check(rqstp, p); 280 } 281 282 int 283 nfssvc_decode_writeargs(struct svc_rqst *rqstp, __be32 *p) 284 { 285 struct nfsd_writeargs *args = rqstp->rq_argp; 286 unsigned int len, hdr, dlen; 287 struct kvec *head = rqstp->rq_arg.head; 288 int v; 289 290 p = decode_fh(p, &args->fh); 291 if (!p) 292 return 0; 293 294 p++; /* beginoffset */ 295 args->offset = ntohl(*p++); /* offset */ 296 p++; /* totalcount */ 297 len = args->len = ntohl(*p++); 298 /* 299 * The protocol specifies a maximum of 8192 bytes. 300 */ 301 if (len > NFSSVC_MAXBLKSIZE_V2) 302 return 0; 303 304 /* 305 * Check to make sure that we got the right number of 306 * bytes. 307 */ 308 hdr = (void*)p - head->iov_base; 309 if (hdr > head->iov_len) 310 return 0; 311 dlen = head->iov_len + rqstp->rq_arg.page_len - hdr; 312 313 /* 314 * Round the length of the data which was specified up to 315 * the next multiple of XDR units and then compare that 316 * against the length which was actually received. 317 * Note that when RPCSEC/GSS (for example) is used, the 318 * data buffer can be padded so dlen might be larger 319 * than required. It must never be smaller. 320 */ 321 if (dlen < XDR_QUADLEN(len)*4) 322 return 0; 323 324 rqstp->rq_vec[0].iov_base = (void*)p; 325 rqstp->rq_vec[0].iov_len = head->iov_len - hdr; 326 v = 0; 327 while (len > rqstp->rq_vec[v].iov_len) { 328 len -= rqstp->rq_vec[v].iov_len; 329 v++; 330 rqstp->rq_vec[v].iov_base = page_address(rqstp->rq_pages[v]); 331 rqstp->rq_vec[v].iov_len = PAGE_SIZE; 332 } 333 rqstp->rq_vec[v].iov_len = len; 334 args->vlen = v + 1; 335 return 1; 336 } 337 338 int 339 nfssvc_decode_createargs(struct svc_rqst *rqstp, __be32 *p) 340 { 341 struct nfsd_createargs *args = rqstp->rq_argp; 342 343 if ( !(p = decode_fh(p, &args->fh)) 344 || !(p = decode_filename(p, &args->name, &args->len))) 345 return 0; 346 p = decode_sattr(p, &args->attrs); 347 348 return xdr_argsize_check(rqstp, p); 349 } 350 351 int 352 nfssvc_decode_renameargs(struct svc_rqst *rqstp, __be32 *p) 353 { 354 struct nfsd_renameargs *args = rqstp->rq_argp; 355 356 if (!(p = decode_fh(p, &args->ffh)) 357 || !(p = decode_filename(p, &args->fname, &args->flen)) 358 || !(p = decode_fh(p, &args->tfh)) 359 || !(p = decode_filename(p, &args->tname, &args->tlen))) 360 return 0; 361 362 return xdr_argsize_check(rqstp, p); 363 } 364 365 int 366 nfssvc_decode_readlinkargs(struct svc_rqst *rqstp, __be32 *p) 367 { 368 struct nfsd_readlinkargs *args = rqstp->rq_argp; 369 370 p = decode_fh(p, &args->fh); 371 if (!p) 372 return 0; 373 args->buffer = page_address(*(rqstp->rq_next_page++)); 374 375 return xdr_argsize_check(rqstp, p); 376 } 377 378 int 379 nfssvc_decode_linkargs(struct svc_rqst *rqstp, __be32 *p) 380 { 381 struct nfsd_linkargs *args = rqstp->rq_argp; 382 383 if (!(p = decode_fh(p, &args->ffh)) 384 || !(p = decode_fh(p, &args->tfh)) 385 || !(p = decode_filename(p, &args->tname, &args->tlen))) 386 return 0; 387 388 return xdr_argsize_check(rqstp, p); 389 } 390 391 int 392 nfssvc_decode_symlinkargs(struct svc_rqst *rqstp, __be32 *p) 393 { 394 struct nfsd_symlinkargs *args = rqstp->rq_argp; 395 396 if ( !(p = decode_fh(p, &args->ffh)) 397 || !(p = decode_filename(p, &args->fname, &args->flen)) 398 || !(p = decode_pathname(p, &args->tname, &args->tlen))) 399 return 0; 400 p = decode_sattr(p, &args->attrs); 401 402 return xdr_argsize_check(rqstp, p); 403 } 404 405 int 406 nfssvc_decode_readdirargs(struct svc_rqst *rqstp, __be32 *p) 407 { 408 struct nfsd_readdirargs *args = rqstp->rq_argp; 409 410 p = decode_fh(p, &args->fh); 411 if (!p) 412 return 0; 413 args->cookie = ntohl(*p++); 414 args->count = ntohl(*p++); 415 args->count = min_t(u32, args->count, PAGE_SIZE); 416 args->buffer = page_address(*(rqstp->rq_next_page++)); 417 418 return xdr_argsize_check(rqstp, p); 419 } 420 421 /* 422 * XDR encode functions 423 */ 424 int 425 nfssvc_encode_void(struct svc_rqst *rqstp, __be32 *p) 426 { 427 return xdr_ressize_check(rqstp, p); 428 } 429 430 int 431 nfssvc_encode_attrstat(struct svc_rqst *rqstp, __be32 *p) 432 { 433 struct nfsd_attrstat *resp = rqstp->rq_resp; 434 435 p = encode_fattr(rqstp, p, &resp->fh, &resp->stat); 436 return xdr_ressize_check(rqstp, p); 437 } 438 439 int 440 nfssvc_encode_diropres(struct svc_rqst *rqstp, __be32 *p) 441 { 442 struct nfsd_diropres *resp = rqstp->rq_resp; 443 444 p = encode_fh(p, &resp->fh); 445 p = encode_fattr(rqstp, p, &resp->fh, &resp->stat); 446 return xdr_ressize_check(rqstp, p); 447 } 448 449 int 450 nfssvc_encode_readlinkres(struct svc_rqst *rqstp, __be32 *p) 451 { 452 struct nfsd_readlinkres *resp = rqstp->rq_resp; 453 454 *p++ = htonl(resp->len); 455 xdr_ressize_check(rqstp, p); 456 rqstp->rq_res.page_len = resp->len; 457 if (resp->len & 3) { 458 /* need to pad the tail */ 459 rqstp->rq_res.tail[0].iov_base = p; 460 *p = 0; 461 rqstp->rq_res.tail[0].iov_len = 4 - (resp->len&3); 462 } 463 return 1; 464 } 465 466 int 467 nfssvc_encode_readres(struct svc_rqst *rqstp, __be32 *p) 468 { 469 struct nfsd_readres *resp = rqstp->rq_resp; 470 471 p = encode_fattr(rqstp, p, &resp->fh, &resp->stat); 472 *p++ = htonl(resp->count); 473 xdr_ressize_check(rqstp, p); 474 475 /* now update rqstp->rq_res to reflect data as well */ 476 rqstp->rq_res.page_len = resp->count; 477 if (resp->count & 3) { 478 /* need to pad the tail */ 479 rqstp->rq_res.tail[0].iov_base = p; 480 *p = 0; 481 rqstp->rq_res.tail[0].iov_len = 4 - (resp->count&3); 482 } 483 return 1; 484 } 485 486 int 487 nfssvc_encode_readdirres(struct svc_rqst *rqstp, __be32 *p) 488 { 489 struct nfsd_readdirres *resp = rqstp->rq_resp; 490 491 xdr_ressize_check(rqstp, p); 492 p = resp->buffer; 493 *p++ = 0; /* no more entries */ 494 *p++ = htonl((resp->common.err == nfserr_eof)); 495 rqstp->rq_res.page_len = (((unsigned long)p-1) & ~PAGE_MASK)+1; 496 497 return 1; 498 } 499 500 int 501 nfssvc_encode_statfsres(struct svc_rqst *rqstp, __be32 *p) 502 { 503 struct nfsd_statfsres *resp = rqstp->rq_resp; 504 struct kstatfs *stat = &resp->stats; 505 506 *p++ = htonl(NFSSVC_MAXBLKSIZE_V2); /* max transfer size */ 507 *p++ = htonl(stat->f_bsize); 508 *p++ = htonl(stat->f_blocks); 509 *p++ = htonl(stat->f_bfree); 510 *p++ = htonl(stat->f_bavail); 511 return xdr_ressize_check(rqstp, p); 512 } 513 514 int 515 nfssvc_encode_entry(void *ccdv, const char *name, 516 int namlen, loff_t offset, u64 ino, unsigned int d_type) 517 { 518 struct readdir_cd *ccd = ccdv; 519 struct nfsd_readdirres *cd = container_of(ccd, struct nfsd_readdirres, common); 520 __be32 *p = cd->buffer; 521 int buflen, slen; 522 523 /* 524 dprintk("nfsd: entry(%.*s off %ld ino %ld)\n", 525 namlen, name, offset, ino); 526 */ 527 528 if (offset > ~((u32) 0)) { 529 cd->common.err = nfserr_fbig; 530 return -EINVAL; 531 } 532 if (cd->offset) 533 *cd->offset = htonl(offset); 534 535 /* truncate filename */ 536 namlen = min(namlen, NFS2_MAXNAMLEN); 537 slen = XDR_QUADLEN(namlen); 538 539 if ((buflen = cd->buflen - slen - 4) < 0) { 540 cd->common.err = nfserr_toosmall; 541 return -EINVAL; 542 } 543 if (ino > ~((u32) 0)) { 544 cd->common.err = nfserr_fbig; 545 return -EINVAL; 546 } 547 *p++ = xdr_one; /* mark entry present */ 548 *p++ = htonl((u32) ino); /* file id */ 549 p = xdr_encode_array(p, name, namlen);/* name length & name */ 550 cd->offset = p; /* remember pointer */ 551 *p++ = htonl(~0U); /* offset of next entry */ 552 553 cd->buflen = buflen; 554 cd->buffer = p; 555 cd->common.err = nfs_ok; 556 return 0; 557 } 558 559 /* 560 * XDR release functions 561 */ 562 void 563 nfssvc_release_fhandle(struct svc_rqst *rqstp) 564 { 565 struct nfsd_fhandle *resp = rqstp->rq_resp; 566 567 fh_put(&resp->fh); 568 } 569