fs/nfsd/nfsxdr.c

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