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, void *dummy) 210 { 211 return xdr_argsize_check(rqstp, p); 212 } 213 214 int 215 nfssvc_decode_fhandle(struct svc_rqst *rqstp, __be32 *p, struct nfsd_fhandle *args) 216 { 217 p = decode_fh(p, &args->fh); 218 if (!p) 219 return 0; 220 return xdr_argsize_check(rqstp, p); 221 } 222 223 int 224 nfssvc_decode_sattrargs(struct svc_rqst *rqstp, __be32 *p, 225 struct nfsd_sattrargs *args) 226 { 227 p = decode_fh(p, &args->fh); 228 if (!p) 229 return 0; 230 p = decode_sattr(p, &args->attrs); 231 232 return xdr_argsize_check(rqstp, p); 233 } 234 235 int 236 nfssvc_decode_diropargs(struct svc_rqst *rqstp, __be32 *p, 237 struct nfsd_diropargs *args) 238 { 239 if (!(p = decode_fh(p, &args->fh)) 240 || !(p = decode_filename(p, &args->name, &args->len))) 241 return 0; 242 243 return xdr_argsize_check(rqstp, p); 244 } 245 246 int 247 nfssvc_decode_readargs(struct svc_rqst *rqstp, __be32 *p, 248 struct nfsd_readargs *args) 249 { 250 unsigned int len; 251 int v; 252 p = decode_fh(p, &args->fh); 253 if (!p) 254 return 0; 255 256 args->offset = ntohl(*p++); 257 len = args->count = ntohl(*p++); 258 p++; /* totalcount - unused */ 259 260 if (!xdr_argsize_check(rqstp, p)) 261 return 0; 262 263 len = min_t(unsigned int, len, NFSSVC_MAXBLKSIZE_V2); 264 265 /* set up somewhere to store response. 266 * We take pages, put them on reslist and include in iovec 267 */ 268 v=0; 269 while (len > 0) { 270 struct page *p = *(rqstp->rq_next_page++); 271 272 rqstp->rq_vec[v].iov_base = page_address(p); 273 rqstp->rq_vec[v].iov_len = min_t(unsigned int, len, PAGE_SIZE); 274 len -= rqstp->rq_vec[v].iov_len; 275 v++; 276 } 277 args->vlen = v; 278 return 1; 279 } 280 281 int 282 nfssvc_decode_writeargs(struct svc_rqst *rqstp, __be32 *p, 283 struct nfsd_writeargs *args) 284 { 285 unsigned int len, hdr, dlen; 286 struct kvec *head = rqstp->rq_arg.head; 287 int v; 288 289 p = decode_fh(p, &args->fh); 290 if (!p) 291 return 0; 292 293 p++; /* beginoffset */ 294 args->offset = ntohl(*p++); /* offset */ 295 p++; /* totalcount */ 296 len = args->len = ntohl(*p++); 297 /* 298 * The protocol specifies a maximum of 8192 bytes. 299 */ 300 if (len > NFSSVC_MAXBLKSIZE_V2) 301 return 0; 302 303 /* 304 * Check to make sure that we got the right number of 305 * bytes. 306 */ 307 hdr = (void*)p - head->iov_base; 308 if (hdr > head->iov_len) 309 return 0; 310 dlen = head->iov_len + rqstp->rq_arg.page_len - hdr; 311 312 /* 313 * Round the length of the data which was specified up to 314 * the next multiple of XDR units and then compare that 315 * against the length which was actually received. 316 * Note that when RPCSEC/GSS (for example) is used, the 317 * data buffer can be padded so dlen might be larger 318 * than required. It must never be smaller. 319 */ 320 if (dlen < XDR_QUADLEN(len)*4) 321 return 0; 322 323 rqstp->rq_vec[0].iov_base = (void*)p; 324 rqstp->rq_vec[0].iov_len = head->iov_len - hdr; 325 v = 0; 326 while (len > rqstp->rq_vec[v].iov_len) { 327 len -= rqstp->rq_vec[v].iov_len; 328 v++; 329 rqstp->rq_vec[v].iov_base = page_address(rqstp->rq_pages[v]); 330 rqstp->rq_vec[v].iov_len = PAGE_SIZE; 331 } 332 rqstp->rq_vec[v].iov_len = len; 333 args->vlen = v + 1; 334 return 1; 335 } 336 337 int 338 nfssvc_decode_createargs(struct svc_rqst *rqstp, __be32 *p, 339 struct nfsd_createargs *args) 340 { 341 if ( !(p = decode_fh(p, &args->fh)) 342 || !(p = decode_filename(p, &args->name, &args->len))) 343 return 0; 344 p = decode_sattr(p, &args->attrs); 345 346 return xdr_argsize_check(rqstp, p); 347 } 348 349 int 350 nfssvc_decode_renameargs(struct svc_rqst *rqstp, __be32 *p, 351 struct nfsd_renameargs *args) 352 { 353 if (!(p = decode_fh(p, &args->ffh)) 354 || !(p = decode_filename(p, &args->fname, &args->flen)) 355 || !(p = decode_fh(p, &args->tfh)) 356 || !(p = decode_filename(p, &args->tname, &args->tlen))) 357 return 0; 358 359 return xdr_argsize_check(rqstp, p); 360 } 361 362 int 363 nfssvc_decode_readlinkargs(struct svc_rqst *rqstp, __be32 *p, struct nfsd_readlinkargs *args) 364 { 365 p = decode_fh(p, &args->fh); 366 if (!p) 367 return 0; 368 if (!xdr_argsize_check(rqstp, p)) 369 return 0; 370 args->buffer = page_address(*(rqstp->rq_next_page++)); 371 372 return 1; 373 } 374 375 int 376 nfssvc_decode_linkargs(struct svc_rqst *rqstp, __be32 *p, 377 struct nfsd_linkargs *args) 378 { 379 if (!(p = decode_fh(p, &args->ffh)) 380 || !(p = decode_fh(p, &args->tfh)) 381 || !(p = decode_filename(p, &args->tname, &args->tlen))) 382 return 0; 383 384 return xdr_argsize_check(rqstp, p); 385 } 386 387 int 388 nfssvc_decode_symlinkargs(struct svc_rqst *rqstp, __be32 *p, 389 struct nfsd_symlinkargs *args) 390 { 391 if ( !(p = decode_fh(p, &args->ffh)) 392 || !(p = decode_filename(p, &args->fname, &args->flen)) 393 || !(p = decode_pathname(p, &args->tname, &args->tlen))) 394 return 0; 395 p = decode_sattr(p, &args->attrs); 396 397 return xdr_argsize_check(rqstp, p); 398 } 399 400 int 401 nfssvc_decode_readdirargs(struct svc_rqst *rqstp, __be32 *p, 402 struct nfsd_readdirargs *args) 403 { 404 p = decode_fh(p, &args->fh); 405 if (!p) 406 return 0; 407 args->cookie = ntohl(*p++); 408 args->count = ntohl(*p++); 409 args->count = min_t(u32, args->count, PAGE_SIZE); 410 if (!xdr_argsize_check(rqstp, p)) 411 return 0; 412 args->buffer = page_address(*(rqstp->rq_next_page++)); 413 414 return 1; 415 } 416 417 /* 418 * XDR encode functions 419 */ 420 int 421 nfssvc_encode_void(struct svc_rqst *rqstp, __be32 *p, void *dummy) 422 { 423 return xdr_ressize_check(rqstp, p); 424 } 425 426 int 427 nfssvc_encode_attrstat(struct svc_rqst *rqstp, __be32 *p, 428 struct nfsd_attrstat *resp) 429 { 430 p = encode_fattr(rqstp, p, &resp->fh, &resp->stat); 431 return xdr_ressize_check(rqstp, p); 432 } 433 434 int 435 nfssvc_encode_diropres(struct svc_rqst *rqstp, __be32 *p, 436 struct nfsd_diropres *resp) 437 { 438 p = encode_fh(p, &resp->fh); 439 p = encode_fattr(rqstp, p, &resp->fh, &resp->stat); 440 return xdr_ressize_check(rqstp, p); 441 } 442 443 int 444 nfssvc_encode_readlinkres(struct svc_rqst *rqstp, __be32 *p, 445 struct nfsd_readlinkres *resp) 446 { 447 *p++ = htonl(resp->len); 448 xdr_ressize_check(rqstp, p); 449 rqstp->rq_res.page_len = resp->len; 450 if (resp->len & 3) { 451 /* need to pad the tail */ 452 rqstp->rq_res.tail[0].iov_base = p; 453 *p = 0; 454 rqstp->rq_res.tail[0].iov_len = 4 - (resp->len&3); 455 } 456 return 1; 457 } 458 459 int 460 nfssvc_encode_readres(struct svc_rqst *rqstp, __be32 *p, 461 struct nfsd_readres *resp) 462 { 463 p = encode_fattr(rqstp, p, &resp->fh, &resp->stat); 464 *p++ = htonl(resp->count); 465 xdr_ressize_check(rqstp, p); 466 467 /* now update rqstp->rq_res to reflect data as well */ 468 rqstp->rq_res.page_len = resp->count; 469 if (resp->count & 3) { 470 /* need to pad the tail */ 471 rqstp->rq_res.tail[0].iov_base = p; 472 *p = 0; 473 rqstp->rq_res.tail[0].iov_len = 4 - (resp->count&3); 474 } 475 return 1; 476 } 477 478 int 479 nfssvc_encode_readdirres(struct svc_rqst *rqstp, __be32 *p, 480 struct nfsd_readdirres *resp) 481 { 482 xdr_ressize_check(rqstp, p); 483 p = resp->buffer; 484 *p++ = 0; /* no more entries */ 485 *p++ = htonl((resp->common.err == nfserr_eof)); 486 rqstp->rq_res.page_len = (((unsigned long)p-1) & ~PAGE_MASK)+1; 487 488 return 1; 489 } 490 491 int 492 nfssvc_encode_statfsres(struct svc_rqst *rqstp, __be32 *p, 493 struct nfsd_statfsres *resp) 494 { 495 struct kstatfs *stat = &resp->stats; 496 497 *p++ = htonl(NFSSVC_MAXBLKSIZE_V2); /* max transfer size */ 498 *p++ = htonl(stat->f_bsize); 499 *p++ = htonl(stat->f_blocks); 500 *p++ = htonl(stat->f_bfree); 501 *p++ = htonl(stat->f_bavail); 502 return xdr_ressize_check(rqstp, p); 503 } 504 505 int 506 nfssvc_encode_entry(void *ccdv, const char *name, 507 int namlen, loff_t offset, u64 ino, unsigned int d_type) 508 { 509 struct readdir_cd *ccd = ccdv; 510 struct nfsd_readdirres *cd = container_of(ccd, struct nfsd_readdirres, common); 511 __be32 *p = cd->buffer; 512 int buflen, slen; 513 514 /* 515 dprintk("nfsd: entry(%.*s off %ld ino %ld)\n", 516 namlen, name, offset, ino); 517 */ 518 519 if (offset > ~((u32) 0)) { 520 cd->common.err = nfserr_fbig; 521 return -EINVAL; 522 } 523 if (cd->offset) 524 *cd->offset = htonl(offset); 525 526 /* truncate filename */ 527 namlen = min(namlen, NFS2_MAXNAMLEN); 528 slen = XDR_QUADLEN(namlen); 529 530 if ((buflen = cd->buflen - slen - 4) < 0) { 531 cd->common.err = nfserr_toosmall; 532 return -EINVAL; 533 } 534 if (ino > ~((u32) 0)) { 535 cd->common.err = nfserr_fbig; 536 return -EINVAL; 537 } 538 *p++ = xdr_one; /* mark entry present */ 539 *p++ = htonl((u32) ino); /* file id */ 540 p = xdr_encode_array(p, name, namlen);/* name length & name */ 541 cd->offset = p; /* remember pointer */ 542 *p++ = htonl(~0U); /* offset of next entry */ 543 544 cd->buflen = buflen; 545 cd->buffer = p; 546 cd->common.err = nfs_ok; 547 return 0; 548 } 549 550 /* 551 * XDR release functions 552 */ 553 int 554 nfssvc_release_fhandle(struct svc_rqst *rqstp, __be32 *p, 555 struct nfsd_fhandle *resp) 556 { 557 fh_put(&resp->fh); 558 return 1; 559 } 560