support/export/client.c

   1 /*
   2  * support/export/client.c
   3  *
   4  * Maintain list of nfsd clients.
   5  *
   6  * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
   7  */
   8
   9 #include "config.h"
  10
  11 #include <sys/types.h>
  12 #include <netinet/in.h>
  13 #include <arpa/inet.h>
  14 #include <stdlib.h>
  15 #include <string.h>
  16 #include <netdb.h>
  17 #include "xmalloc.h"
  18 #include "misc.h"
  19 #include "nfslib.h"
  20 #include "exportfs.h"
  21
  22 /* netgroup stuff never seems to be defined in any header file. Linux is
  23  * not alone in this.
  24  */
  25 #if !defined(__GLIBC__) || __GLIBC__ < 2
  26 extern int      innetgr(char *netgr, char *host, char *, char *);
  27 #endif
  28 static void     client_init(nfs_client *clp, const char *hname,
  29                                         struct hostent *hp);
  30 static int      client_checkaddr(nfs_client *clp, struct in_addr addr);
  31
  32 nfs_client      *clientlist[MCL_MAXTYPES] = { NULL, };
  33
  34
  35 /* if canonical is set, then we *know* this is already a canonical name
  36  * so hostname lookup is avoided.
  37  * This is used when reading /proc/fs/nfs/exports
  38  */
  39 nfs_client *
  40 client_lookup(char *hname, int canonical)
  41 {
  42         nfs_client      *clp = NULL;
  43         int             htype;
  44         struct hostent  *hp = NULL;
  45
  46         htype = client_gettype(hname);
  47
  48         if (htype == MCL_FQDN && !canonical) {
  49                 struct hostent *hp2;
  50                 hp = gethostbyname(hname);
  51                 if (hp == NULL || hp->h_addrtype != AF_INET) {
  52                         xlog(L_ERROR, "%s has non-inet addr", hname);
  53                         return NULL;
  54                 }
  55                 /* make sure we have canonical name */
  56                 hp2 = hostent_dup(hp);
  57                 hp = gethostbyaddr(hp2->h_addr, hp2->h_length,
  58                                    hp2->h_addrtype);
  59                 if (hp) {
  60                         hp = hostent_dup(hp);
  61                         /* but now we might not have all addresses... */
  62                         if (hp2->h_addr_list[1]) {
  63                                 struct hostent *hp3 =
  64                                         gethostbyname(hp->h_name);
  65                                 if (hp3) {
  66                                         free(hp);
  67                                         hp = hostent_dup(hp3);
  68                                 }
  69                         }
  70                         free(hp2);
  71                 } else
  72                         hp = hp2;
  73
  74                 hname = (char *) hp->h_name;
  75
  76                 for (clp = clientlist[htype]; clp; clp = clp->m_next) {
  77                         if (client_check(clp, hp))
  78                                 break;
  79                 }
  80         } else {
  81                 for (clp = clientlist[htype]; clp; clp = clp->m_next) {
  82                         if (strcasecmp(hname, clp->m_hostname)==0)
  83                                 break;
  84                 }
  85         }
  86
  87         if (!clp) {
  88                 clp = (nfs_client *) xmalloc(sizeof(*clp));
  89                 memset(clp, 0, sizeof(*clp));
  90                 clp->m_type = htype;
  91                 client_init(clp, hname, NULL);
  92                 client_add(clp);
  93         }
  94
  95         if (htype == MCL_FQDN && clp->m_naddr == 0 && hp != NULL) {
  96                 char    **ap = hp->h_addr_list;
  97                 int     i;
  98
  99                 for (i = 0; *ap && i < NFSCLNT_ADDRMAX; i++, ap++)
 100                         clp->m_addrlist[i] = *(struct in_addr *)*ap;
 101                 clp->m_naddr = i;
 102         }
 103
 104         if (hp)
 105                 free (hp);
 106
 107         return clp;
 108 }
 109
 110 nfs_client *
 111 client_dup(nfs_client *clp, struct hostent *hp)
 112 {
 113         nfs_client              *new;
 114
 115         new = (nfs_client *) xmalloc(sizeof(*new));
 116         memcpy(new, clp, sizeof(*new));
 117         new->m_type = MCL_FQDN;
 118
 119         client_init(new, (char *) hp->h_name, hp);
 120         client_add(new);
 121         return new;
 122 }
 123
 124 static void
 125 client_init(nfs_client *clp, const char *hname, struct hostent *hp)
 126 {
 127         if (hp) {
 128                 strncpy(clp->m_hostname, hp->h_name,
 129                         sizeof (clp->m_hostname) -  1);
 130         } else {
 131                 strncpy(clp->m_hostname, hname,
 132                         sizeof (clp->m_hostname) - 1);
 133         }
 134         clp->m_hostname[sizeof (clp->m_hostname) - 1] = '\0';
 135
 136         clp->m_exported = 0;
 137         clp->m_count = 0;
 138
 139         if (clp->m_type == MCL_SUBNETWORK) {
 140                 char    *cp = strchr(clp->m_hostname, '/');
 141
 142                 *cp = '\0';
 143                 clp->m_addrlist[0].s_addr = inet_addr(clp->m_hostname);
 144                 if (strchr(cp + 1, '.')) {
 145                         clp->m_addrlist[1].s_addr = inet_addr(cp+1);
 146                 }
 147                 else {
 148                         int netmask = atoi(cp + 1);
 149                         if (0 < netmask && netmask <= 32) {
 150                                 clp->m_addrlist[1].s_addr =
 151                                         htonl ((uint32_t) ~0 << (32 - netmask));
 152                         }
 153                         else {
 154                                 xlog(L_FATAL, "invalid netmask `%s' for %s",
 155                                      cp + 1, clp->m_hostname);
 156                         }
 157                 }
 158                 *cp = '/';
 159                 clp->m_naddr = 0;
 160         } else if (!hp) {
 161                 clp->m_naddr = 0;
 162         } else {
 163                 char    **ap = hp->h_addr_list;
 164                 int     i;
 165
 166                 for (i = 0; *ap && i < NFSCLNT_ADDRMAX; i++, ap++) {
 167                         clp->m_addrlist[i] = *(struct in_addr *)*ap;
 168                 }
 169                 clp->m_naddr = i;
 170         }
 171 }
 172
 173 void
 174 client_add(nfs_client *clp)
 175 {
 176         nfs_client      **cpp;
 177
 178         if (clp->m_type < 0 || clp->m_type >= MCL_MAXTYPES)
 179                 xlog(L_FATAL, "unknown client type in client_add");
 180         cpp = clientlist + clp->m_type;
 181         while (*cpp)
 182                 cpp = &((*cpp)->m_next);
 183         clp->m_next = NULL;
 184         *cpp = clp;
 185 }
 186
 187 void
 188 client_release(nfs_client *clp)
 189 {
 190         if (clp->m_count <= 0)
 191                 xlog(L_FATAL, "client_free: m_count <= 0!");
 192         clp->m_count--;
 193 }
 194
 195 void
 196 client_freeall(void)
 197 {
 198         nfs_client      *clp, **head;
 199         int             i;
 200
 201         for (i = 0; i < MCL_MAXTYPES; i++) {
 202                 head = clientlist + i;
 203                 while (*head) {
 204                         *head = (clp = *head)->m_next;
 205                         xfree(clp);
 206                 }
 207         }
 208 }
 209
 210 nfs_client *
 211 client_find(struct hostent *hp)
 212 {
 213         nfs_client      *clp;
 214         int             i;
 215
 216         for (i = 0; i < MCL_MAXTYPES; i++) {
 217                 for (clp = clientlist[i]; clp; clp = clp->m_next) {
 218                         if (!client_check(clp, hp))
 219                                 continue;
 220 #ifdef notdef
 221                         if (clp->m_type == MCL_FQDN)
 222                                 return clp;
 223                         return client_dup(clp, hp);
 224 #else
 225                         return clp;
 226 #endif
 227                 }
 228         }
 229         return NULL;
 230 }
 231
 232 /*
 233  * Match a host (given its hostent record) to a client record. This
 234  * is usually called from mountd.
 235  */
 236 int
 237 client_check(nfs_client *clp, struct hostent *hp)
 238 {
 239         char    *hname = (char *) hp->h_name;
 240         char    *cname = clp->m_hostname;
 241         char    **ap;
 242
 243         switch (clp->m_type) {
 244         case MCL_FQDN:
 245         case MCL_SUBNETWORK:
 246                 for (ap = hp->h_addr_list; *ap; ap++) {
 247                         if (client_checkaddr(clp, *(struct in_addr *) *ap))
 248                                 return 1;
 249                 }
 250                 return 0;
 251         case MCL_WILDCARD:
 252                 if (wildmat(hname, cname))
 253                         return 1;
 254                 else {
 255                         for (ap = hp->h_aliases; *ap; ap++)
 256                                 if (wildmat(*ap, cname))
 257                                         return 1;
 258                 }
 259                 return 0;
 260         case MCL_NETGROUP:
 261 #ifdef HAVE_INNETGR
 262                 {
 263                         char    *dot;
 264                         int     match;
 265                         struct hostent *nhp = NULL;
 266                         struct sockaddr_in addr;
 267
 268                         /* First, try to match the hostname without
 269                          * splitting off the domain */
 270                         if (innetgr(cname+1, hname, NULL, NULL))
 271                                 return 1;
 272
 273                         /* If hname is ip address convert to FQDN */
 274                         if (inet_aton(hname, &addr.sin_addr) &&
 275                            (nhp = gethostbyaddr((const char *)&(addr.sin_addr),
 276                             sizeof(addr.sin_addr), AF_INET))) {
 277                                 hname = (char *)nhp->h_name;
 278                                 if (innetgr(cname+1, hname, NULL, NULL))
 279                                         return 1;
 280                         }
 281
 282                         /* Okay, strip off the domain (if we have one) */
 283                         if ((dot = strchr(hname, '.')) == NULL)
 284                                 return 0;
 285
 286                         *dot = '\0';
 287                         match = innetgr(cname+1, hname, NULL, NULL);
 288                         *dot = '.';
 289
 290                         return match;
 291                 }
 292 #else
 293                 return 0;
 294 #endif
 295         case MCL_ANONYMOUS:
 296                 return 1;
 297         default:
 298                 xlog(L_FATAL, "internal: bad client type %d", clp->m_type);
 299         }
 300
 301         return 0;
 302 }
 303
 304 static int
 305 client_checkaddr(nfs_client *clp, struct in_addr addr)
 306 {
 307         int     i;
 308
 309         switch (clp->m_type) {
 310         case MCL_FQDN:
 311                 for (i = 0; i < clp->m_naddr; i++) {
 312                         if (clp->m_addrlist[i].s_addr == addr.s_addr)
 313                                 return 1;
 314                 }
 315                 return 0;
 316         case MCL_SUBNETWORK:
 317                 return !((clp->m_addrlist[0].s_addr ^ addr.s_addr)
 318                         & clp->m_addrlist[1].s_addr);
 319         }
 320         return 0;
 321 }
 322
 323 int
 324 client_gettype(char *ident)
 325 {
 326         char    *sp;
 327
 328         if (ident[0] == '\0' || strcmp(ident, "*")==0)
 329                 return MCL_ANONYMOUS;
 330         if (ident[0] == '@') {
 331 #ifndef HAVE_INNETGR
 332                 xlog(L_WARNING, "netgroup support not compiled in");
 333 #endif
 334                 return MCL_NETGROUP;
 335         }
 336         for (sp = ident; *sp; sp++) {
 337                 if (*sp == '*' || *sp == '?' || *sp == '[')
 338                         return MCL_WILDCARD;
 339                 if (*sp == '/')
 340                         return MCL_SUBNETWORK;
 341                 if (*sp == '\\' && sp[1])
 342                         sp++;
 343         }
 344         return MCL_FQDN;
 345 }