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