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