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