SAFE public projects git trees. - safe/jmp/linux-2.6/blob - net/sunrpc/svcauth_unix.c

   1 #include <linux/types.h>
   2 #include <linux/sched.h>
   3 #include <linux/module.h>
   4 #include <linux/sunrpc/types.h>
   5 #include <linux/sunrpc/xdr.h>
   6 #include <linux/sunrpc/svcsock.h>
   7 #include <linux/sunrpc/svcauth.h>
   8 #include <linux/err.h>
   9 #include <linux/seq_file.h>
  10 #include <linux/hash.h>
  11 #include <linux/string.h>
  12
  13 #define RPCDBG_FACILITY RPCDBG_AUTH
  14
  15
  16 /*
  17  * AUTHUNIX and AUTHNULL credentials are both handled here.
  18  * AUTHNULL is treated just like AUTHUNIX except that the uid/gid
  19  * are always nobody (-2).  i.e. we do the same IP address checks for
  20  * AUTHNULL as for AUTHUNIX, and that is done here.
  21  */
  22
  23
  24 struct unix_domain {
  25         struct auth_domain      h;
  26         int     addr_changes;
  27         /* other stuff later */
  28 };
  29
  30 extern struct auth_ops svcauth_unix;
  31
  32 struct auth_domain *unix_domain_find(char *name)
  33 {
  34         struct auth_domain *rv;
  35         struct unix_domain *new = NULL;
  36
  37         rv = auth_domain_lookup(name, NULL);
  38         while(1) {
  39                 if (rv != &new->h) {
  40                         if (new) auth_domain_put(&new->h);
  41                         return rv;
  42                 }
  43                 if (rv && rv->flavour != &svcauth_unix) {
  44                         auth_domain_put(rv);
  45                         return NULL;
  46                 }
  47                 if (rv)
  48                         return rv;
  49
  50                 new = kmalloc(sizeof(*new), GFP_KERNEL);
  51                 if (new == NULL)
  52                         return NULL;
  53                 kref_init(&new->h.ref);
  54                 new->h.name = kstrdup(name, GFP_KERNEL);
  55                 new->h.flavour = &svcauth_unix;
  56                 new->addr_changes = 0;
  57                 rv = auth_domain_lookup(name, &new->h);
  58         }
  59 }
  60
  61 static void svcauth_unix_domain_release(struct auth_domain *dom)
  62 {
  63         struct unix_domain *ud = container_of(dom, struct unix_domain, h);
  64
  65         kfree(dom->name);
  66         kfree(ud);
  67 }
  68
  69
  70 /**************************************************
  71  * cache for IP address to unix_domain
  72  * as needed by AUTH_UNIX
  73  */
  74 #define IP_HASHBITS     8
  75 #define IP_HASHMAX      (1<<IP_HASHBITS)
  76 #define IP_HASHMASK     (IP_HASHMAX-1)
  77
  78 struct ip_map {
  79         struct cache_head       h;
  80         char                    m_class[8]; /* e.g. "nfsd" */
  81         struct in_addr          m_addr;
  82         struct unix_domain      *m_client;
  83         int                     m_add_change;
  84 };
  85 static struct cache_head        *ip_table[IP_HASHMAX];
  86
  87 static void ip_map_put(struct cache_head *item, struct cache_detail *cd)
  88 {
  89         struct ip_map *im = container_of(item, struct ip_map,h);
  90         if (cache_put(item, cd)) {
  91                 if (test_bit(CACHE_VALID, &item->flags) &&
  92                     !test_bit(CACHE_NEGATIVE, &item->flags))
  93                         auth_domain_put(&im->m_client->h);
  94                 kfree(im);
  95         }
  96 }
  97
  98 #if IP_HASHBITS == 8
  99 /* hash_long on a 64 bit machine is currently REALLY BAD for
 100  * IP addresses in reverse-endian (i.e. on a little-endian machine).
 101  * So use a trivial but reliable hash instead
 102  */
 103 static inline int hash_ip(unsigned long ip)
 104 {
 105         int hash = ip ^ (ip>>16);
 106         return (hash ^ (hash>>8)) & 0xff;
 107 }
 108 #endif
 109
 110 static inline int ip_map_hash(struct ip_map *item)
 111 {
 112         return hash_str(item->m_class, IP_HASHBITS) ^
 113                 hash_ip((unsigned long)item->m_addr.s_addr);
 114 }
 115 static inline int ip_map_match(struct ip_map *item, struct ip_map *tmp)
 116 {
 117         return strcmp(tmp->m_class, item->m_class) == 0
 118                 && tmp->m_addr.s_addr == item->m_addr.s_addr;
 119 }
 120 static inline void ip_map_init(struct ip_map *new, struct ip_map *item)
 121 {
 122         strcpy(new->m_class, item->m_class);
 123         new->m_addr.s_addr = item->m_addr.s_addr;
 124 }
 125 static inline void ip_map_update(struct ip_map *new, struct ip_map *item)
 126 {
 127         kref_get(&item->m_client->h.ref);
 128         new->m_client = item->m_client;
 129         new->m_add_change = item->m_add_change;
 130 }
 131
 132 static void ip_map_request(struct cache_detail *cd,
 133                                   struct cache_head *h,
 134                                   char **bpp, int *blen)
 135 {
 136         char text_addr[20];
 137         struct ip_map *im = container_of(h, struct ip_map, h);
 138         __u32 addr = im->m_addr.s_addr;
 139
 140         snprintf(text_addr, 20, "%u.%u.%u.%u",
 141                  ntohl(addr) >> 24 & 0xff,
 142                  ntohl(addr) >> 16 & 0xff,
 143                  ntohl(addr) >>  8 & 0xff,
 144                  ntohl(addr) >>  0 & 0xff);
 145
 146         qword_add(bpp, blen, im->m_class);
 147         qword_add(bpp, blen, text_addr);
 148         (*bpp)[-1] = '\n';
 149 }
 150
 151 static struct ip_map *ip_map_lookup(struct ip_map *, int);
 152
 153 static int ip_map_parse(struct cache_detail *cd,
 154                           char *mesg, int mlen)
 155 {
 156         /* class ipaddress [domainname] */
 157         /* should be safe just to use the start of the input buffer
 158          * for scratch: */
 159         char *buf = mesg;
 160         int len;
 161         int b1,b2,b3,b4;
 162         char c;
 163         struct ip_map ipm, *ipmp;
 164         struct auth_domain *dom;
 165         time_t expiry;
 166
 167         if (mesg[mlen-1] != '\n')
 168                 return -EINVAL;
 169         mesg[mlen-1] = 0;
 170
 171         /* class */
 172         len = qword_get(&mesg, ipm.m_class, sizeof(ipm.m_class));
 173         if (len <= 0) return -EINVAL;
 174
 175         /* ip address */
 176         len = qword_get(&mesg, buf, mlen);
 177         if (len <= 0) return -EINVAL;
 178
 179         if (sscanf(buf, "%u.%u.%u.%u%c", &b1, &b2, &b3, &b4, &c) != 4)
 180                 return -EINVAL;
 181
 182         expiry = get_expiry(&mesg);
 183         if (expiry ==0)
 184                 return -EINVAL;
 185
 186         /* domainname, or empty for NEGATIVE */
 187         len = qword_get(&mesg, buf, mlen);
 188         if (len < 0) return -EINVAL;
 189
 190         if (len) {
 191                 dom = unix_domain_find(buf);
 192                 if (dom == NULL)
 193                         return -ENOENT;
 194         } else
 195                 dom = NULL;
 196
 197         ipm.m_addr.s_addr =
 198                 htonl((((((b1<<8)|b2)<<8)|b3)<<8)|b4);
 199         ipm.h.flags = 0;
 200         if (dom) {
 201                 ipm.m_client = container_of(dom, struct unix_domain, h);
 202                 ipm.m_add_change = ipm.m_client->addr_changes;
 203         } else
 204                 set_bit(CACHE_NEGATIVE, &ipm.h.flags);
 205         ipm.h.expiry_time = expiry;
 206
 207         ipmp = ip_map_lookup(&ipm, 1);
 208         if (ipmp)
 209                 ip_map_put(&ipmp->h, &ip_map_cache);
 210         if (dom)
 211                 auth_domain_put(dom);
 212         if (!ipmp)
 213                 return -ENOMEM;
 214         cache_flush();
 215         return 0;
 216 }
 217
 218 static int ip_map_show(struct seq_file *m,
 219                        struct cache_detail *cd,
 220                        struct cache_head *h)
 221 {
 222         struct ip_map *im;
 223         struct in_addr addr;
 224         char *dom = "-no-domain-";
 225
 226         if (h == NULL) {
 227                 seq_puts(m, "#class IP domain\n");
 228                 return 0;
 229         }
 230         im = container_of(h, struct ip_map, h);
 231         /* class addr domain */
 232         addr = im->m_addr;
 233
 234         if (test_bit(CACHE_VALID, &h->flags) &&
 235             !test_bit(CACHE_NEGATIVE, &h->flags))
 236                 dom = im->m_client->h.name;
 237
 238         seq_printf(m, "%s %d.%d.%d.%d %s\n",
 239                    im->m_class,
 240                    htonl(addr.s_addr) >> 24 & 0xff,
 241                    htonl(addr.s_addr) >> 16 & 0xff,
 242                    htonl(addr.s_addr) >>  8 & 0xff,
 243                    htonl(addr.s_addr) >>  0 & 0xff,
 244                    dom
 245                    );
 246         return 0;
 247 }
 248
 249
 250 struct cache_detail ip_map_cache = {
 251         .owner          = THIS_MODULE,
 252         .hash_size      = IP_HASHMAX,
 253         .hash_table     = ip_table,
 254         .name           = "auth.unix.ip",
 255         .cache_put      = ip_map_put,
 256         .cache_request  = ip_map_request,
 257         .cache_parse    = ip_map_parse,
 258         .cache_show     = ip_map_show,
 259 };
 260
 261 static DefineSimpleCacheLookup(ip_map, ip_map)
 262
 263
 264 int auth_unix_add_addr(struct in_addr addr, struct auth_domain *dom)
 265 {
 266         struct unix_domain *udom;
 267         struct ip_map ip, *ipmp;
 268
 269         if (dom->flavour != &svcauth_unix)
 270                 return -EINVAL;
 271         udom = container_of(dom, struct unix_domain, h);
 272         strcpy(ip.m_class, "nfsd");
 273         ip.m_addr = addr;
 274         ip.m_client = udom;
 275         ip.m_add_change = udom->addr_changes+1;
 276         ip.h.flags = 0;
 277         ip.h.expiry_time = NEVER;
 278
 279         ipmp = ip_map_lookup(&ip, 1);
 280
 281         if (ipmp) {
 282                 ip_map_put(&ipmp->h, &ip_map_cache);
 283                 return 0;
 284         } else
 285                 return -ENOMEM;
 286 }
 287
 288 int auth_unix_forget_old(struct auth_domain *dom)
 289 {
 290         struct unix_domain *udom;
 291
 292         if (dom->flavour != &svcauth_unix)
 293                 return -EINVAL;
 294         udom = container_of(dom, struct unix_domain, h);
 295         udom->addr_changes++;
 296         return 0;
 297 }
 298
 299 struct auth_domain *auth_unix_lookup(struct in_addr addr)
 300 {
 301         struct ip_map key, *ipm;
 302         struct auth_domain *rv;
 303
 304         strcpy(key.m_class, "nfsd");
 305         key.m_addr = addr;
 306
 307         ipm = ip_map_lookup(&key, 0);
 308
 309         if (!ipm)
 310                 return NULL;
 311         if (cache_check(&ip_map_cache, &ipm->h, NULL))
 312                 return NULL;
 313
 314         if ((ipm->m_client->addr_changes - ipm->m_add_change) >0) {
 315                 if (test_and_set_bit(CACHE_NEGATIVE, &ipm->h.flags) == 0)
 316                         auth_domain_put(&ipm->m_client->h);
 317                 rv = NULL;
 318         } else {
 319                 rv = &ipm->m_client->h;
 320                 kref_get(&rv->ref);
 321         }
 322         ip_map_put(&ipm->h, &ip_map_cache);
 323         return rv;
 324 }
 325
 326 void svcauth_unix_purge(void)
 327 {
 328         cache_purge(&ip_map_cache);
 329 }
 330
 331 static int
 332 svcauth_unix_set_client(struct svc_rqst *rqstp)
 333 {
 334         struct ip_map key, *ipm;
 335
 336         rqstp->rq_client = NULL;
 337         if (rqstp->rq_proc == 0)
 338                 return SVC_OK;
 339
 340         strcpy(key.m_class, rqstp->rq_server->sv_program->pg_class);
 341         key.m_addr = rqstp->rq_addr.sin_addr;
 342
 343         ipm = ip_map_lookup(&key, 0);
 344
 345         if (ipm == NULL)
 346                 return SVC_DENIED;
 347
 348         switch (cache_check(&ip_map_cache, &ipm->h, &rqstp->rq_chandle)) {
 349                 default:
 350                         BUG();
 351                 case -EAGAIN:
 352                         return SVC_DROP;
 353                 case -ENOENT:
 354                         return SVC_DENIED;
 355                 case 0:
 356                         rqstp->rq_client = &ipm->m_client->h;
 357                         kref_get(&rqstp->rq_client->ref);
 358                         ip_map_put(&ipm->h, &ip_map_cache);
 359                         break;
 360         }
 361         return SVC_OK;
 362 }
 363
 364 static int
 365 svcauth_null_accept(struct svc_rqst *rqstp, u32 *authp)
 366 {
 367         struct kvec     *argv = &rqstp->rq_arg.head[0];
 368         struct kvec     *resv = &rqstp->rq_res.head[0];
 369         struct svc_cred *cred = &rqstp->rq_cred;
 370
 371         cred->cr_group_info = NULL;
 372         rqstp->rq_client = NULL;
 373
 374         if (argv->iov_len < 3*4)
 375                 return SVC_GARBAGE;
 376
 377         if (svc_getu32(argv) != 0) {
 378                 dprintk("svc: bad null cred\n");
 379                 *authp = rpc_autherr_badcred;
 380                 return SVC_DENIED;
 381         }
 382         if (svc_getu32(argv) != RPC_AUTH_NULL || svc_getu32(argv) != 0) {
 383                 dprintk("svc: bad null verf\n");
 384                 *authp = rpc_autherr_badverf;
 385                 return SVC_DENIED;
 386         }
 387
 388         /* Signal that mapping to nobody uid/gid is required */
 389         cred->cr_uid = (uid_t) -1;
 390         cred->cr_gid = (gid_t) -1;
 391         cred->cr_group_info = groups_alloc(0);
 392         if (cred->cr_group_info == NULL)
 393                 return SVC_DROP; /* kmalloc failure - client must retry */
 394
 395         /* Put NULL verifier */
 396         svc_putu32(resv, RPC_AUTH_NULL);
 397         svc_putu32(resv, 0);
 398
 399         return SVC_OK;
 400 }
 401
 402 static int
 403 svcauth_null_release(struct svc_rqst *rqstp)
 404 {
 405         if (rqstp->rq_client)
 406                 auth_domain_put(rqstp->rq_client);
 407         rqstp->rq_client = NULL;
 408         if (rqstp->rq_cred.cr_group_info)
 409                 put_group_info(rqstp->rq_cred.cr_group_info);
 410         rqstp->rq_cred.cr_group_info = NULL;
 411
 412         return 0; /* don't drop */
 413 }
 414
 415
 416 struct auth_ops svcauth_null = {
 417         .name           = "null",
 418         .owner          = THIS_MODULE,
 419         .flavour        = RPC_AUTH_NULL,
 420         .accept         = svcauth_null_accept,
 421         .release        = svcauth_null_release,
 422         .set_client     = svcauth_unix_set_client,
 423 };
 424
 425
 426 static int
 427 svcauth_unix_accept(struct svc_rqst *rqstp, u32 *authp)
 428 {
 429         struct kvec     *argv = &rqstp->rq_arg.head[0];
 430         struct kvec     *resv = &rqstp->rq_res.head[0];
 431         struct svc_cred *cred = &rqstp->rq_cred;
 432         u32             slen, i;
 433         int             len   = argv->iov_len;
 434
 435         cred->cr_group_info = NULL;
 436         rqstp->rq_client = NULL;
 437
 438         if ((len -= 3*4) < 0)
 439                 return SVC_GARBAGE;
 440
 441         svc_getu32(argv);                       /* length */
 442         svc_getu32(argv);                       /* time stamp */
 443         slen = XDR_QUADLEN(ntohl(svc_getu32(argv)));    /* machname length */
 444         if (slen > 64 || (len -= (slen + 3)*4) < 0)
 445                 goto badcred;
 446         argv->iov_base = (void*)((u32*)argv->iov_base + slen);  /* skip machname */
 447         argv->iov_len -= slen*4;
 448
 449         cred->cr_uid = ntohl(svc_getu32(argv));         /* uid */
 450         cred->cr_gid = ntohl(svc_getu32(argv));         /* gid */
 451         slen = ntohl(svc_getu32(argv));                 /* gids length */
 452         if (slen > 16 || (len -= (slen + 2)*4) < 0)
 453                 goto badcred;
 454         cred->cr_group_info = groups_alloc(slen);
 455         if (cred->cr_group_info == NULL)
 456                 return SVC_DROP;
 457         for (i = 0; i < slen; i++)
 458                 GROUP_AT(cred->cr_group_info, i) = ntohl(svc_getu32(argv));
 459
 460         if (svc_getu32(argv) != RPC_AUTH_NULL || svc_getu32(argv) != 0) {
 461                 *authp = rpc_autherr_badverf;
 462                 return SVC_DENIED;
 463         }
 464
 465         /* Put NULL verifier */
 466         svc_putu32(resv, RPC_AUTH_NULL);
 467         svc_putu32(resv, 0);
 468
 469         return SVC_OK;
 470
 471 badcred:
 472         *authp = rpc_autherr_badcred;
 473         return SVC_DENIED;
 474 }
 475
 476 static int
 477 svcauth_unix_release(struct svc_rqst *rqstp)
 478 {
 479         /* Verifier (such as it is) is already in place.
 480          */
 481         if (rqstp->rq_client)
 482                 auth_domain_put(rqstp->rq_client);
 483         rqstp->rq_client = NULL;
 484         if (rqstp->rq_cred.cr_group_info)
 485                 put_group_info(rqstp->rq_cred.cr_group_info);
 486         rqstp->rq_cred.cr_group_info = NULL;
 487
 488         return 0;
 489 }
 490
 491
 492 struct auth_ops svcauth_unix = {
 493         .name           = "unix",
 494         .owner          = THIS_MODULE,
 495         .flavour        = RPC_AUTH_UNIX,
 496         .accept         = svcauth_unix_accept,
 497         .release        = svcauth_unix_release,
 498         .domain_release = svcauth_unix_domain_release,
 499         .set_client     = svcauth_unix_set_client,
 500 };
 501