include/netinet/ip_nat.h

   1 /*
   2  * Copyright (C) 1995-2001, 2003 by Darren Reed.
   3  *
   4  * See the IPFILTER.LICENCE file for details on licencing.
   5  *
   6  * @(#)ip_nat.h 1.5 2/4/96
   7  * $Id: ip_nat.h,v 2.90.2.11 2005/06/18 02:41:32 darrenr Exp $
   8  *
   9  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
  10  * Use is subject to license terms.
  11  */
  12
  13 #ifndef __IP_NAT_H__
  14 #define __IP_NAT_H__
  15
  16 #ifndef SOLARIS
  17 #define SOLARIS (defined(sun) && (defined(__svr4__) || defined(__SVR4)))
  18 #endif
  19
  20 #if defined(__STDC__) || defined(__GNUC__) || defined(_AIX51)
  21 #define SIOCADNAT       _IOW('r', 60, struct ipfobj)
  22 #define SIOCRMNAT       _IOW('r', 61, struct ipfobj)
  23 #define SIOCGNATS       _IOWR('r', 62, struct ipfobj)
  24 #define SIOCGNATL       _IOWR('r', 63, struct ipfobj)
  25 #else
  26 #define SIOCADNAT       _IOW(r, 60, struct ipfobj)
  27 #define SIOCRMNAT       _IOW(r, 61, struct ipfobj)
  28 #define SIOCGNATS       _IOWR(r, 62, struct ipfobj)
  29 #define SIOCGNATL       _IOWR(r, 63, struct ipfobj)
  30 #endif
  31
  32 #undef  LARGE_NAT       /* define this if you're setting up a system to NAT
  33                          * LARGE numbers of networks/hosts - i.e. in the
  34                          * hundreds or thousands.  In such a case, you should
  35                          * also change the RDR_SIZE and NAT_SIZE below to more
  36                          * appropriate sizes.  The figures below were used for
  37                          * a setup with 1000-2000 networks to NAT.
  38                          */
  39 #ifndef NAT_SIZE
  40 # ifdef LARGE_NAT
  41 #  define       NAT_SIZE        2047
  42 # else
  43 #  define       NAT_SIZE        127
  44 # endif
  45 #endif
  46 #ifndef RDR_SIZE
  47 # ifdef LARGE_NAT
  48 #  define       RDR_SIZE        2047
  49 # else
  50 #  define       RDR_SIZE        127
  51 # endif
  52 #endif
  53 #ifndef HOSTMAP_SIZE
  54 # ifdef LARGE_NAT
  55 #  define       HOSTMAP_SIZE    8191
  56 # else
  57 #  define       HOSTMAP_SIZE    2047
  58 # endif
  59 #endif
  60 #ifndef NAT_TABLE_MAX
  61 /*
  62  * This is newly introduced and for the sake of "least surprise", the numbers
  63  * present aren't what we'd normally use for creating a proper hash table.
  64  */
  65 # ifdef LARGE_NAT
  66 #  define       NAT_TABLE_MAX   180000
  67 # else
  68 #  define       NAT_TABLE_MAX   30000
  69 # endif
  70 #endif
  71 #ifndef NAT_TABLE_SZ
  72 # ifdef LARGE_NAT
  73 #  define       NAT_TABLE_SZ    16383
  74 # else
  75 #  define       NAT_TABLE_SZ    2047
  76 # endif
  77 #endif
  78 #ifndef APR_LABELLEN
  79 #define APR_LABELLEN    16
  80 #endif
  81
  82 #define DEF_NAT_AGE     1200     /* 10 minutes (600 seconds) */
  83
  84 struct ipstate;
  85 struct ap_session;
  86
  87 typedef struct  nat     {
  88         ipfmutex_t      nat_lock;
  89         struct  nat     *nat_next;
  90         struct  nat     **nat_pnext;
  91         struct  nat     *nat_hnext[2];
  92         struct  nat     **nat_phnext[2];
  93         struct  hostmap *nat_hm;
  94         void            *nat_data;
  95         struct  nat     **nat_me;
  96         struct  ipstate *nat_state;
  97         struct  ap_session      *nat_aps;               /* proxy session */
  98         frentry_t       *nat_fr;        /* filter rule ptr if appropriate */
  99         struct  ipnat   *nat_ptr;       /* pointer back to the rule */
 100         void            *nat_ifps[2];
 101         void            *nat_sync;
 102         ipftqent_t      nat_tqe;
 103         u_32_t          nat_flags;
 104         u_32_t          nat_sumd[2];    /* ip checksum delta for data segment */
 105         u_32_t          nat_ipsumd;     /* ip checksum delta for ip header */
 106         u_32_t          nat_mssclamp;   /* if != zero clamp MSS to this */
 107         i6addr_t        nat_inip6;
 108         i6addr_t        nat_outip6;
 109         i6addr_t        nat_oip6;               /* other ip */
 110         U_QUAD_T        nat_pkts[2];
 111         U_QUAD_T        nat_bytes[2];
 112         union   {
 113                 udpinfo_t       nat_unu;
 114                 tcpinfo_t       nat_unt;
 115                 icmpinfo_t      nat_uni;
 116                 greinfo_t       nat_ugre;
 117         } nat_un;
 118         u_short         nat_oport;              /* other port */
 119         u_short         nat_use;
 120         u_char          nat_p;                  /* protocol for NAT */
 121         int             nat_dir;
 122         int             nat_ref;                /* reference count */
 123         int             nat_hv[2];
 124         char            nat_ifnames[2][LIFNAMSIZ];
 125         int             nat_rev;                /* 0 = forward, 1 = reverse */
 126         int             nat_v;
 127         int             nat_redir;              /* copy of in_redir */
 128 } nat_t;
 129
 130 #define nat_inip        nat_inip6.in4
 131 #define nat_outip       nat_outip6.in4
 132 #define nat_oip         nat_oip6.in4
 133 #define nat_age         nat_tqe.tqe_die
 134 #define nat_inport      nat_un.nat_unt.ts_sport
 135 #define nat_outport     nat_un.nat_unt.ts_dport
 136 #define nat_type        nat_un.nat_uni.ici_type
 137 #define nat_seq         nat_un.nat_uni.ici_seq
 138 #define nat_id          nat_un.nat_uni.ici_id
 139 #define nat_tcpstate    nat_tqe.tqe_state
 140
 141 /*
 142  * Values for nat_dir
 143  */
 144 #define NAT_INBOUND     0
 145 #define NAT_OUTBOUND    1
 146
 147 /*
 148  * Definitions for nat_flags
 149  */
 150 #define NAT_TCP         0x0001  /* IPN_TCP */
 151 #define NAT_UDP         0x0002  /* IPN_UDP */
 152 #define NAT_ICMPERR     0x0004  /* IPN_ICMPERR */
 153 #define NAT_ICMPQUERY   0x0008  /* IPN_ICMPQUERY */
 154 #define NAT_SEARCH      0x0010
 155 #define NAT_SLAVE       0x0020  /* Slave connection for a proxy */
 156 #define NAT_NOTRULEPORT 0x0040
 157
 158 #define NAT_TCPUDP      (NAT_TCP|NAT_UDP)
 159 #define NAT_TCPUDPICMP  (NAT_TCP|NAT_UDP|NAT_ICMPERR)
 160 #define NAT_TCPUDPICMPQ (NAT_TCP|NAT_UDP|NAT_ICMPQUERY)
 161 #define NAT_FROMRULE    (NAT_TCP|NAT_UDP)
 162
 163 /* 0x0100 reserved for FI_W_SPORT */
 164 /* 0x0200 reserved for FI_W_DPORT */
 165 /* 0x0400 reserved for FI_W_SADDR */
 166 /* 0x0800 reserved for FI_W_DADDR */
 167 /* 0x1000 reserved for FI_W_NEWFR */
 168 /* 0x2000 reserved for SI_CLONE */
 169 /* 0x4000 reserved for SI_CLONED */
 170 /* 0x8000 reserved for SI_IGNOREPKT */
 171
 172 #define NAT_DEBUG       0x800000
 173
 174 typedef struct  ipnat   {
 175         struct  ipnat   *in_next;               /* NAT rule list next */
 176         struct  ipnat   *in_rnext;              /* rdr rule hash next */
 177         struct  ipnat   **in_prnext;            /* prior rdr next ptr */
 178         struct  ipnat   *in_mnext;              /* map rule hash next */
 179         struct  ipnat   **in_pmnext;            /* prior map next ptr */
 180         struct  ipftq   *in_tqehead[2];
 181         void            *in_ifps[2];
 182         void            *in_apr;
 183         char            *in_comment;
 184         i6addr_t        in_next6;
 185         u_long          in_space;
 186         u_long          in_hits;
 187         u_int           in_use;
 188         u_int           in_hv;
 189         int             in_flineno;             /* conf. file line number */
 190         u_short         in_pnext;
 191         u_char          in_v;
 192         u_char          in_xxx;
 193         /* From here to the end is covered by IPN_CMPSIZ */
 194         u_32_t          in_flags;
 195         u_32_t          in_mssclamp;            /* if != 0 clamp MSS to this */
 196         u_int           in_age[2];
 197         int             in_redir;               /* see below for values */
 198         int             in_p;                   /* protocol. */
 199         i6addr_t        in_in[2];
 200         i6addr_t        in_out[2];
 201         i6addr_t        in_src[2];
 202         frtuc_t         in_tuc;
 203         u_short         in_port[2];
 204         u_short         in_ppip;                /* ports per IP. */
 205         u_short         in_ippip;               /* IP #'s per IP# */
 206         char            in_ifnames[2][LIFNAMSIZ];
 207         char            in_plabel[APR_LABELLEN];        /* proxy label. */
 208         ipftag_t        in_tag;
 209 } ipnat_t;
 210
 211 #define in_pmin         in_port[0]      /* Also holds static redir port */
 212 #define in_pmax         in_port[1]
 213 #define in_nextip       in_next6.in4
 214 #define in_nip          in_next6.in4.s_addr
 215 #define in_inip         in_in[0].in4.s_addr
 216 #define in_inmsk        in_in[1].in4.s_addr
 217 #define in_outip        in_out[0].in4.s_addr
 218 #define in_outmsk       in_out[1].in4.s_addr
 219 #define in_srcip        in_src[0].in4.s_addr
 220 #define in_srcmsk       in_src[1].in4.s_addr
 221 #define in_scmp         in_tuc.ftu_scmp
 222 #define in_dcmp         in_tuc.ftu_dcmp
 223 #define in_stop         in_tuc.ftu_stop
 224 #define in_dtop         in_tuc.ftu_dtop
 225 #define in_sport        in_tuc.ftu_sport
 226 #define in_dport        in_tuc.ftu_dport
 227
 228 /*
 229  * Bit definitions for in_flags
 230  */
 231 #define IPN_ANY         0x00000
 232 #define IPN_TCP         0x00001
 233 #define IPN_UDP         0x00002
 234 #define IPN_TCPUDP      (IPN_TCP|IPN_UDP)
 235 #define IPN_ICMPERR     0x00004
 236 #define IPN_TCPUDPICMP  (IPN_TCP|IPN_UDP|IPN_ICMPERR)
 237 #define IPN_ICMPQUERY   0x00008
 238 #define IPN_TCPUDPICMPQ (IPN_TCP|IPN_UDP|IPN_ICMPQUERY)
 239 #define IPN_RF          (IPN_TCPUDP|IPN_DELETE|IPN_ICMPERR)
 240 #define IPN_AUTOPORTMAP 0x00010
 241 #define IPN_IPRANGE     0x00020
 242 #define IPN_FILTER      0x00040
 243 #define IPN_SPLIT       0x00080
 244 #define IPN_ROUNDR      0x00100
 245 #define IPN_NOTSRC      0x04000
 246 #define IPN_NOTDST      0x08000
 247 #define IPN_DYNSRCIP    0x10000 /* dynamic src IP# */
 248 #define IPN_DYNDSTIP    0x20000 /* dynamic dst IP# */
 249 #define IPN_DELETE      0x40000
 250 #define IPN_STICKY      0x80000
 251 #define IPN_FRAG        0x100000
 252 #define IPN_FIXEDDPORT  0x200000
 253 #define IPN_FINDFORWARD 0x400000
 254 #define IPN_IN          0x800000
 255 #define IPN_SEQUENTIAL  0x1000000
 256 #define IPN_USERFLAGS   (IPN_TCPUDP|IPN_AUTOPORTMAP|IPN_IPRANGE|IPN_SPLIT|\
 257                          IPN_ROUNDR|IPN_FILTER|IPN_NOTSRC|IPN_NOTDST|\
 258                          IPN_FRAG|IPN_STICKY|IPN_FIXEDDPORT|IPN_ICMPQUERY|\
 259                          IPN_SEQUENTIAL)
 260
 261 /*
 262  * Values for in_redir
 263  */
 264 #define NAT_MAP         0x01
 265 #define NAT_REDIRECT    0x02
 266 #define NAT_BIMAP       (NAT_MAP|NAT_REDIRECT)
 267 #define NAT_MAPBLK      0x04
 268
 269 #define MAPBLK_MINPORT  1024    /* don't use reserved ports for src port */
 270 #define USABLE_PORTS    (65536 - MAPBLK_MINPORT)
 271
 272 #define IPN_CMPSIZ      (sizeof (ipnat_t) - offsetof(ipnat_t, in_flags))
 273
 274 typedef struct  natlookup {
 275         i6addr_t        nl_inipaddr;
 276         i6addr_t        nl_outipaddr;
 277         i6addr_t        nl_realipaddr;
 278         int             nl_v;
 279         int             nl_flags;
 280         u_short         nl_inport;
 281         u_short         nl_outport;
 282         u_short         nl_realport;
 283 } natlookup_t;
 284
 285 #define nl_inip         nl_inipaddr.in4
 286 #define nl_outip        nl_outipaddr.in4
 287 #define nl_realip       nl_realipaddr.in4
 288 #define nl_inip6        nl_inipaddr.in6
 289 #define nl_outip6       nl_outipaddr.in6
 290 #define nl_realip6      nl_realipaddr.in6
 291
 292
 293 typedef struct  nat_save    {
 294         void    *ipn_next;
 295         struct  nat     ipn_nat;
 296         struct  ipnat   ipn_ipnat;
 297         struct  frentry ipn_fr;
 298         int     ipn_dsize;
 299         char    ipn_data[4];
 300 } nat_save_t;
 301
 302 #define ipn_rule        ipn_nat.nat_fr
 303
 304 typedef struct  natget  {
 305         void    *ng_ptr;
 306         int     ng_sz;
 307 } natget_t;
 308
 309
 310 #undef  tr_flags
 311 typedef struct  nattrpnt        {
 312         struct  in_addr tr_dstip;       /* real destination IP# */
 313         struct  in_addr tr_srcip;       /* real source IP# */
 314         struct  in_addr tr_locip;       /* local source IP# */
 315         u_int   tr_flags;
 316         int     tr_expire;
 317         u_short tr_dstport;     /* real destination port# */
 318         u_short tr_srcport;     /* real source port# */
 319         u_short tr_locport;     /* local source port# */
 320         struct  nattrpnt        *tr_hnext;
 321         struct  nattrpnt        **tr_phnext;
 322         struct  nattrpnt        *tr_next;
 323         struct  nattrpnt        **tr_pnext;     /* previous next */
 324 } nattrpnt_t;
 325
 326 #define TN_CMPSIZ       offsetof(nattrpnt_t, tr_hnext)
 327
 328
 329 /*
 330  * This structure gets used to help NAT sessions keep the same NAT rule (and
 331  * thus translation for IP address) when:
 332  * (a) round-robin redirects are in use
 333  * (b) different IP add
 334  */
 335 typedef struct  hostmap {
 336         struct  hostmap *hm_next;
 337         struct  hostmap **hm_pnext;
 338         struct  hostmap *hm_hnext;
 339         struct  hostmap **hm_phnext;
 340         struct  ipnat   *hm_ipnat;
 341         i6addr_t        hm_src;
 342         i6addr_t        hm_dst;
 343         i6addr_t        hm_map;
 344         u_32_t          hm_port;
 345         int             hm_ref;
 346         int             hm_v;
 347 } hostmap_t;
 348
 349 #define hm_srcip        hm_src.in4
 350 #define hm_dstip        hm_dst.in4
 351 #define hm_mapip        hm_map.in4
 352 #define hm_srcip6       hm_src.in6
 353 #define hm_dstip6       hm_dst.in6
 354 #define hm_mapip6       hm_map.in6
 355
 356
 357 /*
 358  * Structure used to pass information in to nat_newmap and nat_newrdr.
 359  */
 360 typedef struct  natinfo {
 361         ipnat_t         *nai_np;
 362         u_32_t          nai_nflags;
 363         u_32_t          nai_flags;
 364         struct  in_addr nai_ip;
 365         u_short         nai_port;
 366         u_short         nai_nport;
 367         u_short         nai_sport;
 368         u_short         nai_dport;
 369 } natinfo_t;
 370
 371
 372 typedef struct  natstat {
 373         u_long  ns_mapped[2];
 374         u_long  ns_rules;
 375         u_long  ns_added;
 376         u_long  ns_expire;
 377         u_long  ns_inuse;
 378         u_long  ns_logged;
 379         u_long  ns_logfail;
 380         u_long  ns_memfail;
 381         u_long  ns_badnat;
 382         u_long  ns_addtrpnt;
 383         nat_t   **ns_table[2];
 384         hostmap_t **ns_maptable;
 385         ipnat_t *ns_list;
 386         void    *ns_apslist;
 387         u_int   ns_wilds;
 388         u_int   ns_nattab_sz;
 389         u_int   ns_nattab_max;
 390         u_int   ns_rultab_sz;
 391         u_int   ns_rdrtab_sz;
 392         u_int   ns_trpntab_sz;
 393         u_int   ns_hostmap_sz;
 394         nat_t   *ns_instances;
 395         nattrpnt_t *ns_trpntlist;
 396         hostmap_t *ns_maplist;
 397         u_long  *ns_bucketlen[2];
 398         u_int   ns_orphans;
 399         u_long  ns_uncreate[2][2];
 400 } natstat_t;
 401
 402 typedef struct  natlog {
 403         i6addr_t        nlg_origip;
 404         i6addr_t        nlg_outip;
 405         i6addr_t        nlg_inip;
 406         u_short         nlg_origport;
 407         u_short         nlg_outport;
 408         u_short         nlg_inport;
 409         u_short         nlg_type;
 410         int             nlg_rule;
 411         U_QUAD_T        nlg_pkts[2];
 412         U_QUAD_T        nlg_bytes[2];
 413         u_char          nlg_p;
 414         int             nlg_v;
 415 } natlog_t;
 416
 417
 418 #define NL_NEWMAP       NAT_MAP
 419 #define NL_NEWRDR       NAT_REDIRECT
 420 #define NL_NEWBIMAP     NAT_BIMAP
 421 #define NL_NEWBLOCK     NAT_MAPBLK
 422 #define NL_DESTROY      0xfffc
 423 #define NL_CLONE        0xfffd
 424 #define NL_FLUSH        0xfffe
 425 #define NL_EXPIRE       0xffff
 426
 427 #define NAT_HASH_FN(k, l, m)    (((k) + ((k) >> 12) + l) % (m))
 428 #define NAT_HASH_FN6(k, l, m)   ((((u_32_t *)(k))[3] \
 429                                 + (((u_32_t *)(k))[3] >> 12) \
 430                                 + (((u_32_t *)(k))[2]) \
 431                                 + (((u_32_t *)(k))[2] >> 12) \
 432                                 + (((u_32_t *)(k))[1]) \
 433                                 + (((u_32_t *)(k))[1] >> 12) \
 434                                 + (((u_32_t *)(k))[0]) \
 435                                 + (((u_32_t *)(k))[0] >> 12) \
 436                                 + l) % (m))
 437
 438 #define LONG_SUM(in)    (((in) & 0xffff) + ((in) >> 16))
 439 #define LONG_SUM6(in)   (LONG_SUM(ntohl(((u_32_t *)(in))[0])) + \
 440                          LONG_SUM(ntohl(((u_32_t *)(in))[1])) + \
 441                          LONG_SUM(ntohl(((u_32_t *)(in))[2])) + \
 442                          LONG_SUM(ntohl(((u_32_t *)(in))[3])))
 443
 444 #define CALC_SUMD(s1, s2, sd) { \
 445                             (s1) = ((s1) & 0xffff) + ((s1) >> 16); \
 446                             (s2) = ((s2) & 0xffff) + ((s2) >> 16); \
 447                             /* Do it twice */ \
 448                             (s1) = ((s1) & 0xffff) + ((s1) >> 16); \
 449                             (s2) = ((s2) & 0xffff) + ((s2) >> 16); \
 450                             /* Because ~1 == -2, We really need ~1 == -1 */ \
 451                             if ((s1) > (s2)) (s2)--; \
 452                             (sd) = (s2) - (s1); \
 453                             (sd) = ((sd) & 0xffff) + ((sd) >> 16); }
 454
 455 #define NAT_SYSSPACE            0x80000000
 456 #define NAT_LOCKHELD            0x40000000
 457
 458 extern  void    fr_natsync __P((void *, ipf_stack_t *));
 459 extern  void    fr_nataddrsync __P((int, void *, void *, ipf_stack_t *));
 460 extern  void    fr_natifpsync __P((int, int, void *, char *, ipf_stack_t *));
 461
 462 #if defined(__OpenBSD__)
 463 extern  void    nat_ifdetach __P((void *, ipf_stack_t *));
 464 #endif
 465 extern  int     fr_nat_ioctl __P((caddr_t, ioctlcmd_t, int, int, void *, ipf_stack_t *));
 466 extern  int     fr_natinit __P((ipf_stack_t *));
 467 extern  nat_t   *nat_new __P((fr_info_t *, ipnat_t *, nat_t **, u_int, int));
 468 extern  nat_t   *nat_outlookup __P((fr_info_t *, u_int, u_int, struct in_addr,
 469                                  struct in_addr));
 470 extern  void    fix_datacksum __P((u_short *, u_32_t));
 471 extern  nat_t   *nat_inlookup __P((fr_info_t *, u_int, u_int, struct in_addr,
 472                                 struct in_addr));
 473 extern  nat_t   *nat_tnlookup __P((fr_info_t *, int));
 474 extern  nat_t   *nat_maplookup __P((void *, u_int, struct in_addr,
 475                                 struct in_addr));
 476 extern  nat_t   *nat_lookupredir __P((natlookup_t *, ipf_stack_t *));
 477 extern  nat_t   *nat_icmperrorlookup __P((fr_info_t *, int));
 478 extern  nat_t   *nat_icmperror __P((fr_info_t *, u_int *, int));
 479 extern  int     nat_delete __P((struct nat *, int, ipf_stack_t *));
 480 extern  int     nat_insert __P((nat_t *, int, ipf_stack_t *));
 481
 482 extern  int     fr_checknatout __P((fr_info_t *, u_32_t *));
 483 extern  int     fr_natout __P((fr_info_t *, nat_t *, int, u_32_t));
 484 extern  int     fr_checknatin __P((fr_info_t *, u_32_t *));
 485 extern  int     fr_natin __P((fr_info_t *, nat_t *, int, u_32_t));
 486 extern  void    fr_natunload __P((ipf_stack_t *));
 487 extern  void    nat_uncreate __P((fr_info_t *));
 488 extern  void    fr_natexpire __P((ipf_stack_t *));
 489 extern  void    nat_log __P((struct nat *, u_int, ipf_stack_t *));
 490 extern  void    fix_incksum __P((u_short *, u_32_t));
 491 extern  void    fix_outcksum __P((u_short *, u_32_t));
 492 extern  void    fr_ipnatderef __P((ipnat_t **, ipf_stack_t *));
 493 extern  void    fr_natderef __P((nat_t **, ipf_stack_t *));
 494 extern  u_short *nat_proto __P((fr_info_t *, nat_t *, u_int));
 495 extern  void    nat_update __P((fr_info_t *, nat_t *, ipnat_t *));
 496 extern  void    fr_setnatqueue __P((nat_t *, int, ipf_stack_t *));
 497 extern  void    fr_hostmapdel __P((hostmap_t **));
 498 #if SOLARIS2 >= 10
 499 extern  void    fr_natifindexsync __P((void *, void *, ipf_stack_t *));
 500 #endif
 501
 502 extern  nat_t   *fr_natclone __P((fr_info_t *, nat_t *));
 503 extern  void    nat_delrdr __P((struct ipnat *));
 504 extern  void    nat_delnat __P((struct ipnat *));
 505 extern  int     nat_wildok __P((nat_t *, int, int, int, int));
 506 extern  void    nat_calc_chksum_diffs __P((nat_t *));
 507
 508 #ifdef  USE_INET6
 509 extern  void    nat6_addnat __P((ipnat_t *, ipf_stack_t *));
 510 extern  void    nat6_addrdr __P((ipnat_t *, ipf_stack_t *));
 511 extern  nat_t   *nat6_new __P((fr_info_t *, ipnat_t *, nat_t **, u_int, int));
 512 extern  nat_t   *nat6_outlookup __P((fr_info_t *, u_int, u_int,
 513                                 struct in6_addr *, struct in6_addr *));
 514 extern  nat_t   *nat6_inlookup __P((fr_info_t *, u_int, u_int,
 515                                 struct in6_addr *, struct in6_addr *));
 516 extern  nat_t   *nat6_lookupredir __P((natlookup_t *, ipf_stack_t *));
 517 extern  nat_t   *nat6_icmperrorlookup __P((fr_info_t *, int));
 518 extern  nat_t   *nat6_icmperror __P((fr_info_t *, u_int *, int));
 519 extern  int     nat6_insert __P((nat_t *, int, ipf_stack_t *));
 520 extern  int     fr_checknat6out __P((fr_info_t *, u_32_t *));
 521 extern  int     fr_nat6out __P((fr_info_t *, nat_t *, int, u_32_t));
 522 extern  int     fr_checknat6in __P((fr_info_t *, u_32_t *));
 523 extern  int     fr_nat6in __P((fr_info_t *, nat_t *, int, u_32_t));
 524 #endif
 525
 526 #endif /* __IP_NAT_H__ */