utils/mountd/cache.c

   1
   2 /*
   3  * Handle communication with knfsd internal cache
   4  *
   5  * We open /proc/net/rpc/{auth.unix.ip,nfsd.export,nfsd.fh}/channel
   6  * and listen for requests (using my_svc_run)
   7  *
   8  */
   9
  10 #ifdef HAVE_CONFIG_H
  11 #include <config.h>
  12 #endif
  13
  14 #include <sys/types.h>
  15 #include <sys/select.h>
  16 #include <sys/stat.h>
  17 #include <time.h>
  18 #include <netinet/in.h>
  19 #include <arpa/inet.h>
  20 #include <unistd.h>
  21 #include <fcntl.h>
  22 #include <errno.h>
  23 #include <ctype.h>
  24 #include <pwd.h>
  25 #include <grp.h>
  26 #include <mntent.h>
  27 #include "misc.h"
  28 #include "nfslib.h"
  29 #include "exportfs.h"
  30 #include "mountd.h"
  31 #include "xmalloc.h"
  32 #include "fsloc.h"
  33 #include "pseudoflavors.h"
  34
  35 #ifdef USE_BLKID
  36 #include "blkid/blkid.h"
  37 #endif
  38
  39
  40 enum nfsd_fsid {
  41         FSID_DEV = 0,
  42         FSID_NUM,
  43         FSID_MAJOR_MINOR,
  44         FSID_ENCODE_DEV,
  45         FSID_UUID4_INUM,
  46         FSID_UUID8,
  47         FSID_UUID16,
  48         FSID_UUID16_INUM,
  49 };
  50
  51 /*
  52  * Support routines for text-based upcalls.
  53  * Fields are separated by spaces.
  54  * Fields are either mangled to quote space tab newline slosh with slosh
  55  * or a hexified with a leading \x
  56  * Record is terminated with newline.
  57  *
  58  */
  59 int cache_export_ent(char *domain, struct exportent *exp, char *p);
  60
  61
  62 char *lbuf  = NULL;
  63 int lbuflen = 0;
  64 extern int use_ipaddr;
  65
  66 void auth_unix_ip(FILE *f)
  67 {
  68         /* requests are
  69          *  class IP-ADDR
  70          * Ignore if class != "nfsd"
  71          * Otherwise find domainname and write back:
  72          *
  73          *  "nfsd" IP-ADDR expiry domainname
  74          */
  75         char *cp;
  76         char class[20];
  77         char ipaddr[20];
  78         char *client = NULL;
  79         struct in_addr addr;
  80         struct hostent *he = NULL;
  81         if (readline(fileno(f), &lbuf, &lbuflen) != 1)
  82                 return;
  83
  84         cp = lbuf;
  85
  86         if (qword_get(&cp, class, 20) <= 0 ||
  87             strcmp(class, "nfsd") != 0)
  88                 return;
  89
  90         if (qword_get(&cp, ipaddr, 20) <= 0)
  91                 return;
  92
  93         if (inet_aton(ipaddr, &addr)==0)
  94                 return;
  95
  96         auth_reload();
  97
  98         /* addr is a valid, interesting address, find the domain name... */
  99         if (!use_ipaddr) {
 100                 he = client_resolve(addr);
 101                 client = client_compose(he);
 102         }
 103
 104         qword_print(f, "nfsd");
 105         qword_print(f, ipaddr);
 106         qword_printint(f, time(0)+30*60);
 107         if (use_ipaddr)
 108                 qword_print(f, ipaddr);
 109         else if (client)
 110                 qword_print(f, *client?client:"DEFAULT");
 111         qword_eol(f);
 112
 113         if (client) free(client);
 114         free(he);
 115 }
 116
 117 void auth_unix_gid(FILE *f)
 118 {
 119         /* Request are
 120          *  uid
 121          * reply is
 122          *  uid expiry count list of group ids
 123          */
 124         int uid;
 125         struct passwd *pw;
 126         gid_t glist[100], *groups = glist;
 127         int ngroups = 100;
 128         int rv, i;
 129         char *cp;
 130
 131         if (readline(fileno(f), &lbuf, &lbuflen) != 1)
 132                 return;
 133
 134         cp = lbuf;
 135         if (qword_get_int(&cp, &uid) != 0)
 136                 return;
 137
 138         pw = getpwuid(uid);
 139         if (!pw)
 140                 rv = -1;
 141         else {
 142                 rv = getgrouplist(pw->pw_name, pw->pw_gid, groups, &ngroups);
 143                 if (rv == -1 && ngroups >= 100) {
 144                         groups = malloc(sizeof(gid_t)*ngroups);
 145                         if (!groups)
 146                                 rv = -1;
 147                         else
 148                                 rv = getgrouplist(pw->pw_name, pw->pw_gid,
 149                                                   groups, &ngroups);
 150                 }
 151         }
 152         qword_printint(f, uid);
 153         qword_printint(f, time(0)+30*60);
 154         if (rv >= 0) {
 155                 qword_printint(f, ngroups);
 156                 for (i=0; i<ngroups; i++)
 157                         qword_printint(f, groups[i]);
 158         }
 159         qword_eol(f);
 160         if (groups != glist)
 161                 free(groups);
 162 }
 163
 164 #if USE_BLKID
 165 int get_uuid(char *path, char *uuid, int uuidlen, char *u)
 166 {
 167         /* extract hex digits from uuidstr and compose a uuid
 168          * of the given length (max 16), xoring bytes to make
 169          * a smaller uuid.  Then compare with uuid
 170          */
 171         int i = 0;
 172         const char *val;
 173
 174         if (path) {
 175                 static blkid_cache cache = NULL;
 176                 struct stat stb;
 177                 char *devname;
 178                 blkid_tag_iterate iter;
 179                 blkid_dev dev;
 180                 const char *type;
 181                 if (cache == NULL)
 182                         blkid_get_cache(&cache, NULL);
 183
 184                 blkid_probe_all_new(cache);
 185
 186                 if (stat(path, &stb) != 0)
 187                         return 0;
 188                 devname = blkid_devno_to_devname(stb.st_dev);
 189                 if (!devname)
 190                         return 0;
 191                 dev = blkid_get_dev(cache, devname, BLKID_DEV_NORMAL);
 192                 free(devname);
 193                 if (!dev)
 194                         return 0;
 195                 iter = blkid_tag_iterate_begin(dev);
 196                 if (!iter)
 197                         return 0;
 198                 while (blkid_tag_next(iter, &type, &val) == 0)
 199                         if (strcmp(type, "UUID") == 0)
 200                                 break;
 201                 blkid_tag_iterate_end(iter);
 202                 if (!type)
 203                         return 0;
 204         } else {
 205                 val = uuid;
 206         }
 207
 208         memset(u, 0, uuidlen);
 209         for ( ; *val ; val++) {
 210                 char c = *val;
 211                 if (!isxdigit(c))
 212                         continue;
 213                 if (isalpha(c)) {
 214                         if (isupper(c))
 215                                 c = c - 'A' + 10;
 216                         else
 217                                 c = c - 'a' + 10;
 218                 } else
 219                         c = c - '0' + 0;
 220                 if ((i&1) == 0)
 221                         c <<= 4;
 222                 u[i/2] ^= c;
 223                 i++;
 224                 if (i == uuidlen*2)
 225                         i = 0;
 226         }
 227         return 1;
 228 }
 229 #endif
 230
 231 /* Iterate through /etc/mtab, finding mountpoints
 232  * at or below a given path
 233  */
 234 static char *next_mnt(void **v, char *p)
 235 {
 236         FILE *f;
 237         struct mntent *me;
 238         int l = strlen(p);
 239         if (*v == NULL) {
 240                 f = setmntent("/etc/mtab", "r");
 241                 *v = f;
 242         } else
 243                 f = *v;
 244         while ((me = getmntent(f)) != NULL &&
 245                (strncmp(me->mnt_dir, p, l) != 0 ||
 246                 me->mnt_dir[l] != '/'))
 247                 ;
 248         if (me == NULL) {
 249                 endmntent(f);
 250                 *v = NULL;
 251                 return NULL;
 252         }
 253         return me->mnt_dir;
 254 }
 255
 256 void nfsd_fh(FILE *f)
 257 {
 258         /* request are:
 259          *  domain fsidtype fsid
 260          * interpret fsid, find export point and options, and write:
 261          *  domain fsidtype fsid expiry path
 262          */
 263         char *cp;
 264         char *dom;
 265         int fsidtype;
 266         int fsidlen;
 267         unsigned int dev, major=0, minor=0;
 268         unsigned int inode=0;
 269         unsigned long long inode64;
 270         unsigned int fsidnum=0;
 271         char fsid[32];
 272         struct exportent *found = NULL;
 273         struct hostent *he = NULL;
 274         struct in_addr addr;
 275         char *found_path = NULL;
 276         nfs_export *exp;
 277         int i;
 278         int dev_missing = 0;
 279         int uuidlen = 0;
 280         char *fhuuid = NULL;
 281
 282         if (readline(fileno(f), &lbuf, &lbuflen) != 1)
 283                 return;
 284
 285         cp = lbuf;
 286
 287         dom = malloc(strlen(cp));
 288         if (dom == NULL)
 289                 return;
 290         if (qword_get(&cp, dom, strlen(cp)) <= 0)
 291                 goto out;
 292         if (qword_get_int(&cp, &fsidtype) != 0)
 293                 goto out;
 294         if (fsidtype < 0 || fsidtype > 7)
 295                 goto out; /* unknown type */
 296         if ((fsidlen = qword_get(&cp, fsid, 32)) <= 0)
 297                 goto out;
 298         switch(fsidtype) {
 299         case FSID_DEV: /* 4 bytes: 2 major, 2 minor, 4 inode */
 300                 if (fsidlen != 8)
 301                         goto out;
 302                 memcpy(&dev, fsid, 4);
 303                 memcpy(&inode, fsid+4, 4);
 304                 major = ntohl(dev)>>16;
 305                 minor = ntohl(dev) & 0xFFFF;
 306                 break;
 307
 308         case FSID_NUM: /* 4 bytes - fsid */
 309                 if (fsidlen != 4)
 310                         goto out;
 311                 memcpy(&fsidnum, fsid, 4);
 312                 break;
 313
 314         case FSID_MAJOR_MINOR: /* 12 bytes: 4 major, 4 minor, 4 inode
 315                  * This format is never actually used but was
 316                  * an historical accident
 317                  */
 318                 if (fsidlen != 12)
 319                         goto out;
 320                 memcpy(&dev, fsid, 4); major = ntohl(dev);
 321                 memcpy(&dev, fsid+4, 4); minor = ntohl(dev);
 322                 memcpy(&inode, fsid+8, 4);
 323                 break;
 324
 325         case FSID_ENCODE_DEV: /* 8 bytes: 4 byte packed device number, 4 inode */
 326                 /* This is *host* endian, not net-byte-order, because
 327                  * no-one outside this host has any business interpreting it
 328                  */
 329                 if (fsidlen != 8)
 330                         goto out;
 331                 memcpy(&dev, fsid, 4);
 332                 memcpy(&inode, fsid+4, 4);
 333                 major = (dev & 0xfff00) >> 8;
 334                 minor = (dev & 0xff) | ((dev >> 12) & 0xfff00);
 335                 break;
 336
 337         case FSID_UUID4_INUM: /* 4 byte inode number and 4 byte uuid */
 338                 if (fsidlen != 8)
 339                         goto out;
 340                 memcpy(&inode, fsid, 4);
 341                 uuidlen = 4;
 342                 fhuuid = fsid+4;
 343                 break;
 344         case FSID_UUID8: /* 8 byte uuid */
 345                 if (fsidlen != 8)
 346                         goto out;
 347                 uuidlen = 8;
 348                 fhuuid = fsid;
 349                 break;
 350         case FSID_UUID16: /* 16 byte uuid */
 351                 if (fsidlen != 16)
 352                         goto out;
 353                 uuidlen = 16;
 354                 fhuuid = fsid;
 355                 break;
 356         case FSID_UUID16_INUM: /* 8 byte inode number and 16 byte uuid */
 357                 if (fsidlen != 24)
 358                         goto out;
 359                 memcpy(&inode64, fsid, 8);
 360                 inode = inode64;
 361                 uuidlen = 16;
 362                 fhuuid = fsid+8;
 363                 break;
 364         }
 365
 366         auth_reload();
 367
 368         /* Now determine export point for this fsid/domain */
 369         for (i=0 ; i < MCL_MAXTYPES; i++) {
 370                 nfs_export *next_exp;
 371                 for (exp = exportlist[i]; exp; exp = next_exp) {
 372                         struct stat stb;
 373                         char u[16];
 374                         char *path;
 375
 376                         if (exp->m_export.e_flags & NFSEXP_CROSSMOUNT) {
 377                                 static nfs_export *prev = NULL;
 378                                 static void *mnt = NULL;
 379
 380                                 if (prev == exp) {
 381                                         /* try a submount */
 382                                         path = next_mnt(&mnt, exp->m_export.e_path);
 383                                         if (!path) {
 384                                                 next_exp = exp->m_next;
 385                                                 prev = NULL;
 386                                                 continue;
 387                                         }
 388                                         next_exp = exp;
 389                                 } else {
 390                                         prev = exp;
 391                                         mnt = NULL;
 392                                         path = exp->m_export.e_path;
 393                                         next_exp = exp;
 394                                 }
 395                         } else {
 396                                 path = exp->m_export.e_path;
 397                                 next_exp = exp->m_next;
 398                         }
 399
 400                         if (!use_ipaddr && !client_member(dom, exp->m_client->m_hostname))
 401                                 continue;
 402                         if (exp->m_export.e_mountpoint &&
 403                             !is_mountpoint(exp->m_export.e_mountpoint[0]?
 404                                            exp->m_export.e_mountpoint:
 405                                            exp->m_export.e_path))
 406                                 dev_missing ++;
 407                         if (stat(path, &stb) != 0)
 408                                 continue;
 409                         if (!S_ISDIR(stb.st_mode) && !S_ISREG(stb.st_mode)) {
 410                                 continue;
 411                         }
 412                         switch(fsidtype){
 413                         case FSID_DEV:
 414                         case FSID_MAJOR_MINOR:
 415                         case FSID_ENCODE_DEV:
 416                                 if (stb.st_ino != inode)
 417                                         continue;
 418                                 if (major != major(stb.st_dev) ||
 419                                     minor != minor(stb.st_dev))
 420                                         continue;
 421                                 break;
 422                         case FSID_NUM:
 423                                 if (((exp->m_export.e_flags & NFSEXP_FSID) == 0 ||
 424                                      exp->m_export.e_fsid != fsidnum))
 425                                         continue;
 426                                 break;
 427                         case FSID_UUID4_INUM:
 428                         case FSID_UUID16_INUM:
 429                                 if (stb.st_ino != inode)
 430                                         continue;
 431                                 goto check_uuid;
 432                         case FSID_UUID8:
 433                         case FSID_UUID16:
 434                                 if (!is_mountpoint(path))
 435                                         continue;
 436                         check_uuid:
 437 #if USE_BLKID
 438                                 if (exp->m_export.e_uuid)
 439                                         get_uuid(NULL, exp->m_export.e_uuid,
 440                                                  uuidlen, u);
 441                                 else if (get_uuid(path, NULL,
 442                                                   uuidlen, u) == 0)
 443                                         continue;
 444
 445                                 if (memcmp(u, fhuuid, uuidlen) != 0)
 446                                         continue;
 447                                 break;
 448 #else
 449                                 continue;
 450 #endif
 451                         }
 452                         if (use_ipaddr) {
 453                                 if (he == NULL) {
 454                                         if (!inet_aton(dom, &addr))
 455                                                 goto out;
 456                                         he = client_resolve(addr);
 457                                 }
 458                                 if (!client_check(exp->m_client, he))
 459                                         continue;
 460                         }
 461                         /* It's a match !! */
 462                         if (!found) {
 463                                 found = &exp->m_export;
 464                                 found_path = strdup(path);
 465                                 if (found_path == NULL)
 466                                         goto out;
 467                         } else if (strcmp(found->e_path, exp->m_export.e_path)!= 0)
 468                         {
 469                                 xlog(L_WARNING, "%s and %s have same filehandle for %s, using first",
 470                                      found_path, path, dom);
 471                         }
 472                 }
 473         }
 474         if (found &&
 475             found->e_mountpoint &&
 476             !is_mountpoint(found->e_mountpoint[0]?
 477                            found->e_mountpoint:
 478                            found->e_path)) {
 479                 /* Cannot export this yet
 480                  * should log a warning, but need to rate limit
 481                    xlog(L_WARNING, "%s not exported as %d not a mountpoint",
 482                    found->e_path, found->e_mountpoint);
 483                  */
 484                 /* FIXME we need to make sure we re-visit this later */
 485                 goto out;
 486         }
 487         if (!found && dev_missing) {
 488                 /* The missing dev could be what we want, so just be
 489                  * quite rather than returning stale yet
 490                  */
 491                 goto out;
 492         }
 493
 494         if (found)
 495                 if (cache_export_ent(dom, found, found_path) < 0)
 496                         found = 0;
 497
 498         qword_print(f, dom);
 499         qword_printint(f, fsidtype);
 500         qword_printhex(f, fsid, fsidlen);
 501         /* The fsid -> path lookup can be quite expensive as it
 502          * potentially stats and reads lots of devices, and some of those
 503          * might have spun-down.  The Answer is not likely to
 504          * change underneath us, and an 'exportfs -f' can always
 505          * remove this from the kernel, so use a really log
 506          * timeout.  Maybe this should be configurable on the command
 507          * line.
 508          */
 509         qword_printint(f, 0x7fffffff);
 510         if (found)
 511                 qword_print(f, found->e_path);
 512         qword_eol(f);
 513  out:
 514         free(found_path);
 515         free(he);
 516         free(dom);
 517         return;
 518 }
 519
 520 static void write_fsloc(FILE *f, struct exportent *ep, char *path)
 521 {
 522         struct servers *servers;
 523
 524         if (ep->e_fslocmethod == FSLOC_NONE)
 525                 return;
 526
 527         servers = replicas_lookup(ep->e_fslocmethod, ep->e_fslocdata, path);
 528         if (!servers)
 529                 return;
 530         qword_print(f, "fsloc");
 531         qword_printint(f, servers->h_num);
 532         if (servers->h_num >= 0) {
 533                 int i;
 534                 for (i=0; i<servers->h_num; i++) {
 535                         qword_print(f, servers->h_mp[i]->h_host);
 536                         qword_print(f, servers->h_mp[i]->h_path);
 537                 }
 538         }
 539         qword_printint(f, servers->h_referral);
 540         release_replicas(servers);
 541 }
 542
 543 static void write_secinfo(FILE *f, struct exportent *ep)
 544 {
 545         struct sec_entry *p;
 546
 547         for (p = ep->e_secinfo; p->flav; p++)
 548                 ; /* Do nothing */
 549         if (p == ep->e_secinfo) {
 550                 /* There was no sec= option */
 551                 return;
 552         }
 553         qword_print(f, "secinfo");
 554         qword_printint(f, p - ep->e_secinfo);
 555         for (p = ep->e_secinfo; p->flav; p++) {
 556                 qword_printint(f, p->flav->fnum);
 557                 qword_printint(f, p->flags);
 558         }
 559
 560 }
 561
 562 static int dump_to_cache(FILE *f, char *domain, char *path, struct exportent *exp)
 563 {
 564         qword_print(f, domain);
 565         qword_print(f, path);
 566         qword_printint(f, time(0)+30*60);
 567         if (exp) {
 568                 qword_printint(f, exp->e_flags);
 569                 qword_printint(f, exp->e_anonuid);
 570                 qword_printint(f, exp->e_anongid);
 571                 qword_printint(f, exp->e_fsid);
 572                 write_fsloc(f, exp, path);
 573                 write_secinfo(f, exp);
 574 #if USE_BLKID
 575                 if (exp->e_uuid == NULL) {
 576                         char u[16];
 577                         if (get_uuid(path, NULL, 16, u)) {
 578                                 qword_print(f, "uuid");
 579                                 qword_printhex(f, u, 16);
 580                         }
 581                 } else if (exp->e_uuid) {
 582                         qword_print(f, "uuid");
 583                         qword_printhex(f, exp->e_uuid, 16);
 584                 }
 585 #endif
 586         }
 587         return qword_eol(f);
 588 }
 589
 590 void nfsd_export(FILE *f)
 591 {
 592         /* requests are:
 593          *  domain path
 594          * determine export options and return:
 595          *  domain path expiry flags anonuid anongid fsid
 596          */
 597
 598         char *cp;
 599         int i;
 600         char *dom, *path;
 601         nfs_export *exp, *found = NULL;
 602         int found_type = 0;
 603         struct in_addr addr;
 604         struct hostent *he = NULL;
 605
 606
 607         if (readline(fileno(f), &lbuf, &lbuflen) != 1)
 608                 return;
 609
 610         cp = lbuf;
 611         dom = malloc(strlen(cp));
 612         path = malloc(strlen(cp));
 613
 614         if (!dom || !path)
 615                 goto out;
 616
 617         if (qword_get(&cp, dom, strlen(lbuf)) <= 0)
 618                 goto out;
 619         if (qword_get(&cp, path, strlen(lbuf)) <= 0)
 620                 goto out;
 621
 622         auth_reload();
 623
 624         /* now find flags for this export point in this domain */
 625         for (i=0 ; i < MCL_MAXTYPES; i++) {
 626                 for (exp = exportlist[i]; exp; exp = exp->m_next) {
 627                         if (!use_ipaddr && !client_member(dom, exp->m_client->m_hostname))
 628                                 continue;
 629                         if (exp->m_export.e_flags & NFSEXP_CROSSMOUNT) {
 630                                 /* if path is a mountpoint below e_path, then OK */
 631                                 int l = strlen(exp->m_export.e_path);
 632                                 if (strcmp(path, exp->m_export.e_path) == 0 ||
 633                                     (strncmp(path, exp->m_export.e_path, l) == 0 &&
 634                                      path[l] == '/' &&
 635                                      is_mountpoint(path)))
 636                                         /* ok */;
 637                                 else
 638                                         continue;
 639                         } else if (strcmp(path, exp->m_export.e_path) != 0)
 640                                 continue;
 641                         if (use_ipaddr) {
 642                                 if (he == NULL) {
 643                                         if (!inet_aton(dom, &addr))
 644                                                 goto out;
 645                                         he = client_resolve(addr);
 646                                 }
 647                                 if (!client_check(exp->m_client, he))
 648                                         continue;
 649                         }
 650                         if (!found) {
 651                                 found = exp;
 652                                 found_type = i;
 653                                 continue;
 654                         }
 655                         /* If one is a CROSSMOUNT, then prefer the longest path */
 656                         if (((found->m_export.e_flags & NFSEXP_CROSSMOUNT) ||
 657                              (found->m_export.e_flags & NFSEXP_CROSSMOUNT)) &&
 658                             strlen(found->m_export.e_path) !=
 659                             strlen(found->m_export.e_path)) {
 660
 661                                 if (strlen(exp->m_export.e_path) >
 662                                     strlen(found->m_export.e_path)) {
 663                                         found = exp;
 664                                         found_type = i;
 665                                 }
 666                                 continue;
 667
 668                         } else if (found_type == i && found->m_warned == 0) {
 669                                 xlog(L_WARNING, "%s exported to both %s and %s, "
 670                                      "arbitrarily choosing options from first",
 671                                      path, found->m_client->m_hostname, exp->m_client->m_hostname,
 672                                      dom);
 673                                 found->m_warned = 1;
 674                         }
 675                 }
 676         }
 677
 678         if (found) {
 679                 if (dump_to_cache(f, dom, path, &found->m_export) < 0) {
 680                         xlog(L_WARNING,
 681                              "Cannot export %s, possibly unsupported filesystem"
 682                              " or fsid= required", path);
 683                         dump_to_cache(f, dom, path, NULL);
 684                 }
 685         } else {
 686                 dump_to_cache(f, dom, path, NULL);
 687         }
 688  out:
 689         if (dom) free(dom);
 690         if (path) free(path);
 691         if (he) free(he);
 692 }
 693
 694
 695 struct {
 696         char *cache_name;
 697         void (*cache_handle)(FILE *f);
 698         FILE *f;
 699 } cachelist[] = {
 700         { "auth.unix.ip", auth_unix_ip},
 701         { "auth.unix.gid", auth_unix_gid},
 702         { "nfsd.export", nfsd_export},
 703         { "nfsd.fh", nfsd_fh},
 704         { NULL, NULL }
 705 };
 706
 707 extern int manage_gids;
 708 void cache_open(void)
 709 {
 710         int i;
 711         for (i=0; cachelist[i].cache_name; i++ ) {
 712                 char path[100];
 713                 if (!manage_gids && cachelist[i].cache_handle == auth_unix_gid)
 714                         continue;
 715                 sprintf(path, "/proc/net/rpc/%s/channel", cachelist[i].cache_name);
 716                 cachelist[i].f = fopen(path, "r+");
 717         }
 718 }
 719
 720 void cache_set_fds(fd_set *fdset)
 721 {
 722         int i;
 723         for (i=0; cachelist[i].cache_name; i++) {
 724                 if (cachelist[i].f)
 725                         FD_SET(fileno(cachelist[i].f), fdset);
 726         }
 727 }
 728
 729 int cache_process_req(fd_set *readfds)
 730 {
 731         int i;
 732         int cnt = 0;
 733         for (i=0; cachelist[i].cache_name; i++) {
 734                 if (cachelist[i].f != NULL &&
 735                     FD_ISSET(fileno(cachelist[i].f), readfds)) {
 736                         cnt++;
 737                         cachelist[i].cache_handle(cachelist[i].f);
 738                         FD_CLR(fileno(cachelist[i].f), readfds);
 739                 }
 740         }
 741         return cnt;
 742 }
 743
 744
 745 /*
 746  * Give IP->domain and domain+path->options to kernel
 747  * % echo nfsd $IP  $[now+30*60] $domain > /proc/net/rpc/auth.unix.ip/channel
 748  * % echo $domain $path $[now+30*60] $options $anonuid $anongid $fsid > /proc/net/rpc/nfsd.export/channel
 749  */
 750
 751 int cache_export_ent(char *domain, struct exportent *exp, char *path)
 752 {
 753         int err;
 754         FILE *f = fopen("/proc/net/rpc/nfsd.export/channel", "w");
 755         if (!f)
 756                 return -1;
 757
 758         err = dump_to_cache(f, domain, exp->e_path, exp);
 759         if (err) {
 760                 xlog(L_WARNING,
 761                      "Cannot export %s, possibly unsupported filesystem or"
 762                      " fsid= required", exp->e_path);
 763         }
 764
 765         while (err == 0 && (exp->e_flags & NFSEXP_CROSSMOUNT) && path) {
 766                 /* really an 'if', but we can break out of
 767                  * a 'while' more easily */
 768                 /* Look along 'path' for other filesystems
 769                  * and export them with the same options
 770                  */
 771                 struct stat stb;
 772                 int l = strlen(exp->e_path);
 773                 int dev;
 774
 775                 if (strlen(path) <= l || path[l] != '/' ||
 776                     strncmp(exp->e_path, path, l) != 0)
 777                         break;
 778                 if (stat(exp->e_path, &stb) != 0)
 779                         break;
 780                 dev = stb.st_dev;
 781                 while(path[l] == '/') {
 782                         char c;
 783                         /* errors for submount should fail whole filesystem */
 784                         int err2;
 785
 786                         l++;
 787                         while (path[l] != '/' && path[l])
 788                                 l++;
 789                         c = path[l];
 790                         path[l] = 0;
 791                         err2 = lstat(path, &stb);
 792                         path[l] = c;
 793                         if (err2 < 0)
 794                                 break;
 795                         if (stb.st_dev == dev)
 796                                 continue;
 797                         dev = stb.st_dev;
 798                         path[l] = 0;
 799                         dump_to_cache(f, domain, path, exp);
 800                         path[l] = c;
 801                 }
 802                 break;
 803         }
 804
 805         fclose(f);
 806         return err;
 807 }
 808
 809 int cache_export(nfs_export *exp, char *path)
 810 {
 811         int err;
 812         FILE *f;
 813
 814         f = fopen("/proc/net/rpc/auth.unix.ip/channel", "w");
 815         if (!f)
 816                 return -1;
 817
 818         qword_print(f, "nfsd");
 819         qword_print(f, inet_ntoa(exp->m_client->m_addrlist[0]));
 820         qword_printint(f, time(0)+30*60);
 821         qword_print(f, exp->m_client->m_hostname);
 822         err = qword_eol(f);
 823
 824         fclose(f);
 825
 826         err = cache_export_ent(exp->m_client->m_hostname, &exp->m_export, path)
 827                 || err;
 828         return err;
 829 }
 830
 831 /* Get a filehandle.
 832  * {
 833  *   echo $domain $path $length
 834  *   read filehandle <&0
 835  * } <> /proc/fs/nfsd/filehandle
 836  */
 837 struct nfs_fh_len *
 838 cache_get_filehandle(nfs_export *exp, int len, char *p)
 839 {
 840         FILE *f = fopen("/proc/fs/nfsd/filehandle", "r+");
 841         char buf[200];
 842         char *bp = buf;
 843         int failed;
 844         static struct nfs_fh_len fh;
 845
 846         if (!f)
 847                 f = fopen("/proc/fs/nfs/filehandle", "r+");
 848         if (!f)
 849                 return NULL;
 850
 851         qword_print(f, exp->m_client->m_hostname);
 852         qword_print(f, p);
 853         qword_printint(f, len);
 854         failed = qword_eol(f);
 855
 856         if (!failed)
 857                 failed = (fgets(buf, sizeof(buf), f) == NULL);
 858         fclose(f);
 859         if (failed)
 860                 return NULL;
 861         memset(fh.fh_handle, 0, sizeof(fh.fh_handle));
 862         fh.fh_size = qword_get(&bp, (char *)fh.fh_handle, NFS3_FHSIZE);
 863         return &fh;
 864 }
 865