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 #include "config.h"
  10
  11 #include <sys/types.h>
  12 #include <sys/select.h>
  13 #include <sys/stat.h>
  14 #include <time.h>
  15 #include <netinet/in.h>
  16 #include <arpa/inet.h>
  17 #include <unistd.h>
  18 #include <fcntl.h>
  19 #include <errno.h>
  20 #include <ctype.h>
  21 #include "misc.h"
  22 #include "nfslib.h"
  23 #include "exportfs.h"
  24 #include "mountd.h"
  25 #include "xmalloc.h"
  26
  27 /*
  28  * Support routines for text-based upcalls.
  29  * Fields are separated by spaces.
  30  * Fields are either mangled to quote space tab newline slosh with slosh
  31  * or a hexified with a leading \x
  32  * Record is terminated with newline.
  33  *
  34  */
  35 void cache_export_ent(char *domain, struct exportent *exp);
  36
  37
  38 char *lbuf  = NULL;
  39 int lbuflen = 0;
  40
  41 void auth_unix_ip(FILE *f)
  42 {
  43         /* requests are
  44          *  class IP-ADDR
  45          * Ignore if class != "nfsd"
  46          * Otherwise find domainname and write back:
  47          *
  48          *  "nfsd" IP-ADDR expiry domainname
  49          */
  50         char *cp;
  51         char class[20];
  52         char ipaddr[20];
  53         char *client;
  54         struct in_addr addr;
  55         if (readline(fileno(f), &lbuf, &lbuflen) != 1)
  56                 return;
  57
  58         cp = lbuf;
  59
  60         if (qword_get(&cp, class, 20) <= 0 ||
  61             strcmp(class, "nfsd") != 0)
  62                 return;
  63
  64         if (qword_get(&cp, ipaddr, 20) <= 0)
  65                 return;
  66
  67         if (inet_aton(ipaddr, &addr)==0)
  68                 return;
  69
  70         auth_reload();
  71
  72         /* addr is a valid, interesting address, find the domain name... */
  73         client = client_compose(addr);
  74
  75
  76         qword_print(f, "nfsd");
  77         qword_print(f, ipaddr);
  78         qword_printint(f, time(0)+30*60);
  79         if (client)
  80                 qword_print(f, *client?client:"DEFAULT");
  81         qword_eol(f);
  82
  83         if (client && strcmp(ipaddr, client))
  84                 mountlist_add(ipaddr, *client?client:"DEFAULT");
  85
  86         if (client) free(client);
  87
  88 }
  89
  90 void nfsd_fh(FILE *f)
  91 {
  92         /* request are:
  93          *  domain fsidtype fsid
  94          * interpret fsid, find export point and options, and write:
  95          *  domain fsidtype fsid expiry path
  96          */
  97         char *cp;
  98         char *dom;
  99         int fsidtype;
 100         int fsidlen;
 101         unsigned int dev, major=0, minor=0;
 102         unsigned int inode=0;
 103         unsigned int fsidnum=0;
 104         char fsid[32];
 105         struct exportent *found = NULL;
 106         nfs_export *exp;
 107         int i;
 108         int dev_missing = 0;
 109
 110         if (readline(fileno(f), &lbuf, &lbuflen) != 1)
 111                 return;
 112
 113         cp = lbuf;
 114
 115         dom = malloc(strlen(cp));
 116         if (dom == NULL)
 117                 return;
 118         if (qword_get(&cp, dom, strlen(cp)) <= 0)
 119                 goto out;
 120         if (qword_get_int(&cp, &fsidtype) != 0)
 121                 goto out;
 122         if (fsidtype < 0 || fsidtype > 1)
 123                 goto out; /* unknown type */
 124         if ((fsidlen = qword_get(&cp, fsid, 32)) <= 0)
 125                 goto out;
 126         switch(fsidtype) {
 127         case 0: /* 4 bytes: 2 major, 2 minor, 4 inode */
 128                 if (fsidlen != 8)
 129                         goto out;
 130                 memcpy(&dev, fsid, 4);
 131                 memcpy(&inode, fsid+4, 4);
 132                 major = ntohl(dev)>>16;
 133                 minor = ntohl(dev) & 0xFFFF;
 134                 break;
 135
 136         case 1: /* 4 bytes - fsid */
 137                 if (fsidlen != 4)
 138                         goto out;
 139                 memcpy(&fsidnum, fsid, 4);
 140                 break;
 141         }
 142
 143         auth_reload();
 144
 145         /* Now determine export point for this fsid/domain */
 146         for (i=0 ; i < MCL_MAXTYPES; i++) {
 147                 for (exp = exportlist[i]; exp; exp = exp->m_next) {
 148                         struct stat stb;
 149
 150                         if (!client_member(dom, exp->m_client->m_hostname))
 151                                 continue;
 152                         if (exp->m_export.e_mountpoint &&
 153                             !is_mountpoint(exp->m_export.e_mountpoint[0]?
 154                                            exp->m_export.e_mountpoint:
 155                                            exp->m_export.e_path))
 156                                 dev_missing ++;
 157                         if (stat(exp->m_export.e_path, &stb) != 0)
 158                                 continue;
 159                         if (fsidtype == 1 &&
 160                             ((exp->m_export.e_flags & NFSEXP_FSID) == 0 ||
 161                              exp->m_export.e_fsid != fsidnum))
 162                                 continue;
 163                         if (fsidtype == 0) {
 164                                 if (stb.st_ino != inode)
 165                                         continue;
 166                                 if (major != major(stb.st_dev) ||
 167                                     minor != minor(stb.st_dev))
 168                                         continue;
 169                         }
 170                         /* It's a match !! */
 171                         if (!found)
 172                                 found = &exp->m_export;
 173                         else if (strcmp(found->e_path, exp->m_export.e_path)!= 0)
 174                         {
 175                                 xlog(L_WARNING, "%s and %s have same filehandle for %s, using first",
 176                                      found->e_path, exp->m_export.e_path, dom);
 177                         }
 178                 }
 179         }
 180         if (found &&
 181             found->e_mountpoint &&
 182             !is_mountpoint(found->e_mountpoint[0]?
 183                            found->e_mountpoint:
 184                            found->e_path)) {
 185                 /* Cannot export this yet
 186                  * should log a warning, but need to rate limit
 187                    xlog(L_WARNING, "%s not exported as %d not a mountpoint",
 188                    found->e_path, found->e_mountpoint);
 189                  */
 190                 /* FIXME we need to make sure we re-visit this later */
 191                 goto out;
 192         }
 193         if (!found && dev_missing) {
 194                 /* The missing dev could be what we want, so just be
 195                  * quite rather than returning stale yet
 196                  */
 197                 goto out;
 198         }
 199
 200         if (found)
 201                 cache_export_ent(dom, found);
 202
 203         qword_print(f, dom);
 204         qword_printint(f, fsidtype);
 205         qword_printhex(f, fsid, fsidlen);
 206         qword_printint(f, time(0)+30*60);
 207         if (found)
 208                 qword_print(f, found->e_path);
 209         qword_eol(f);
 210  out:
 211         free(dom);
 212         return;
 213 }
 214
 215 void nfsd_export(FILE *f)
 216 {
 217         /* requests are:
 218          *  domain path
 219          * determine export options and return:
 220          *  domain path expiry flags anonuid anongid fsid
 221          */
 222
 223         char *cp;
 224         int i;
 225         char *dom, *path;
 226         nfs_export *exp, *found = NULL;
 227
 228
 229         if (readline(fileno(f), &lbuf, &lbuflen) != 1)
 230                 return;
 231
 232         cp = lbuf;
 233         dom = malloc(strlen(cp));
 234         path = malloc(strlen(cp));
 235
 236         if (!dom || !path)
 237                 goto out;
 238
 239         if (qword_get(&cp, dom, strlen(lbuf)) <= 0)
 240                 goto out;
 241         if (qword_get(&cp, path, strlen(lbuf)) <= 0)
 242                 goto out;
 243
 244         auth_reload();
 245
 246         /* now find flags for this export point in this domain */
 247         for (i=0 ; i < MCL_MAXTYPES; i++) {
 248                 for (exp = exportlist[i]; exp; exp = exp->m_next) {
 249                         if (!client_member(dom, exp->m_client->m_hostname))
 250                                 continue;
 251                         if (strcmp(path, exp->m_export.e_path))
 252                                 continue;
 253                         if (!found)
 254                                 found = exp;
 255                         else {
 256                                 xlog(L_WARNING, "%s exported to both %s and %s in %s",
 257                                      path, exp->m_client->m_hostname, found->m_client->m_hostname,
 258                                      dom);
 259                         }
 260                 }
 261         }
 262
 263         qword_print(f, dom);
 264         qword_print(f, path);
 265         qword_printint(f, time(0)+30*60);
 266         if (found) {
 267                 qword_printint(f, found->m_export.e_flags);
 268                 qword_printint(f, found->m_export.e_anonuid);
 269                 qword_printint(f, found->m_export.e_anongid);
 270                 qword_printint(f, found->m_export.e_fsid);
 271                 mountlist_add(dom, path);
 272         }
 273         qword_eol(f);
 274  out:
 275         if (dom) free(dom);
 276         if (path) free(path);
 277 }
 278
 279
 280 struct {
 281         char *cache_name;
 282         void (*cache_handle)(FILE *f);
 283         FILE *f;
 284 } cachelist[] = {
 285         { "auth.unix.ip", auth_unix_ip},
 286         { "nfsd.export", nfsd_export},
 287         { "nfsd.fh", nfsd_fh},
 288         { NULL, NULL }
 289 };
 290
 291 void cache_open(void)
 292 {
 293         int i;
 294         for (i=0; cachelist[i].cache_name; i++ ){
 295                 char path[100];
 296                 sprintf(path, "/proc/net/rpc/%s/channel", cachelist[i].cache_name);
 297                 cachelist[i].f = fopen(path, "r+");
 298         }
 299 }
 300
 301 void cache_set_fds(fd_set *fdset)
 302 {
 303         int i;
 304         for (i=0; cachelist[i].cache_name; i++) {
 305                 if (cachelist[i].f)
 306                         FD_SET(fileno(cachelist[i].f), fdset);
 307         }
 308 }
 309
 310 int cache_process_req(fd_set *readfds)
 311 {
 312         int i;
 313         int cnt = 0;
 314         for (i=0; cachelist[i].cache_name; i++) {
 315                 if (cachelist[i].f != NULL &&
 316                     FD_ISSET(fileno(cachelist[i].f), readfds)) {
 317                         cnt++;
 318                         cachelist[i].cache_handle(cachelist[i].f);
 319                         FD_CLR(fileno(cachelist[i].f), readfds);
 320                 }
 321         }
 322         return cnt;
 323 }
 324
 325
 326 /*
 327  * Give IP->domain and domain+path->options to kernel
 328  * % echo nfsd $IP  $[now+30*60] $domain > /proc/net/rpc/auth.unix.ip/channel
 329  * % echo $domain $path $[now+30*60] $options $anonuid $anongid $fsid > /proc/net/rpc/nfsd.export/channel
 330  */
 331
 332 void cache_export_ent(char *domain, struct exportent *exp)
 333 {
 334
 335         FILE *f = fopen("/proc/net/rpc/nfsd.export/channel", "w");
 336         if (!f)
 337                 return;
 338
 339         qword_print(f, domain);
 340         qword_print(f, exp->e_path);
 341         qword_printint(f, time(0)+30*60);
 342         qword_printint(f, exp->e_flags);
 343         qword_printint(f, exp->e_anonuid);
 344         qword_printint(f, exp->e_anongid);
 345         qword_printint(f, exp->e_fsid);
 346         qword_eol(f);
 347
 348         fclose(f);
 349
 350         mountlist_add(domain, exp->e_path);
 351 }
 352
 353 void cache_export(nfs_export *exp)
 354 {
 355         FILE *f;
 356
 357         f = fopen("/proc/net/rpc/auth.unix.ip/channel", "w");
 358         if (!f)
 359                 return;
 360
 361         qword_print(f, "nfsd");
 362         qword_print(f, inet_ntoa(exp->m_client->m_addrlist[0]));
 363         qword_printint(f, time(0)+30*60);
 364         qword_print(f, exp->m_client->m_hostname);
 365         qword_eol(f);
 366
 367         fclose(f);
 368
 369         if (strcmp(inet_ntoa(exp->m_client->m_addrlist[0]), exp->m_client->m_hostname))
 370                 mountlist_add(inet_ntoa(exp->m_client->m_addrlist[0]), exp->m_client->m_hostname);
 371
 372         cache_export_ent(exp->m_client->m_hostname, &exp->m_export);
 373 }
 374
 375 /* Get a filehandle.
 376  * {
 377  *   echo $domain $path $length
 378  *   read filehandle <&0
 379  * } <> /proc/fs/nfsd/filehandle
 380  */
 381 struct nfs_fh_len *
 382 cache_get_filehandle(nfs_export *exp, int len, char *p)
 383 {
 384         FILE *f = fopen("/proc/fs/nfsd/filehandle", "r+");
 385         char buf[200];
 386         char *bp = buf;
 387         int failed;
 388         static struct nfs_fh_len fh;
 389
 390         if (!f)
 391                 f = fopen("/proc/fs/nfs/filehandle", "r+");
 392         if (!f)
 393                 return NULL;
 394
 395         qword_print(f, exp->m_client->m_hostname);
 396         qword_print(f, p);
 397         qword_printint(f, len);
 398         qword_eol(f);
 399
 400         failed = (fgets(buf, sizeof(buf), f) == NULL);
 401         fclose(f);
 402         if (failed)
 403                 return NULL;
 404         memset(fh.fh_handle, 0, sizeof(fh.fh_handle));
 405         fh.fh_size = qword_get(&bp, fh.fh_handle, NFS3_FHSIZE);
 406         return &fh;
 407 }
 408