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 #ifdef  SOLARIS
  17 #undef  SOLARIS
  18 #endif
  19 #if (defined(sun) && (defined(__svr4__) || defined(__SVR4)))
  20 #define SOLARIS (1)
  21 #else
  22 #define SOLARIS (0)
  23 #endif
  24
  25 #if defined(__STDC__) || defined(__GNUC__) || defined(_AIX51)
  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 #else
  31 #define SIOCADNAT       _IOW(r, 60, struct ipfobj)
  32 #define SIOCRMNAT       _IOW(r, 61, struct ipfobj)
  33 #define SIOCGNATS       _IOWR(r, 62, struct ipfobj)
  34 #define SIOCGNATL       _IOWR(r, 63, struct ipfobj)
  35 #endif
  36
  37 #undef  LARGE_NAT       /* define this if you're setting up a system to NAT
  38                          * LARGE numbers of networks/hosts - i.e. in the
  39                          * hundreds or thousands.  In such a case, you should
  40                          * also change the RDR_SIZE and NAT_SIZE below to more
  41                          * appropriate sizes.  The figures below were used for
  42                          * a setup with 1000-2000 networks to NAT.
  43                          */
  44 #ifndef NAT_SIZE
  45 # ifdef LARGE_NAT
  46 #  define       NAT_SIZE        2047
  47 # else
  48 #  define       NAT_SIZE        127
  49 # endif
  50 #endif
  51 #ifndef RDR_SIZE
  52 # ifdef LARGE_NAT
  53 #  define       RDR_SIZE        2047
  54 # else
  55 #  define       RDR_SIZE        127
  56 # endif
  57 #endif
  58 #ifndef HOSTMAP_SIZE
  59 # ifdef LARGE_NAT
  60 #  define       HOSTMAP_SIZE    8191
  61 # else
  62 #  define       HOSTMAP_SIZE    2047
  63 # endif
  64 #endif
  65 #ifndef NAT_TABLE_MAX
  66 /*
  67  * This is newly introduced and for the sake of "least surprise", the numbers
  68  * present aren't what we'd normally use for creating a proper hash table.
  69  */
  70 # ifdef LARGE_NAT
  71 #  define       NAT_TABLE_MAX   180000
  72 # else
  73 #  define       NAT_TABLE_MAX   30000
  74 # endif
  75 #endif
  76 #ifndef NAT_TABLE_SZ
  77 # ifdef LARGE_NAT
  78 #  define       NAT_TABLE_SZ    16383
  79 # else
  80 #  define       NAT_TABLE_SZ    2047
  81 # endif
  82 #endif
  83 #ifndef APR_LABELLEN
  84 #define APR_LABELLEN    16
  85 #endif
  86
  87 #define DEF_NAT_AGE     1200     /* 10 minutes (600 seconds) */
  88
  89 struct ipstate;
  90 struct ap_session;
  91
  92 typedef struct  nat     {
  93         ipfmutex_t      nat_lock;
  94         struct  nat     *nat_next;
  95         struct  nat     **nat_pnext;
  96         struct  nat     *nat_hnext[2];
  97         struct  nat     **nat_phnext[2];
  98         struct  hostmap *nat_hm;
  99         void            *nat_data;
 100         struct  nat     **nat_me;
 101         struct  ipstate *nat_state;
 102         struct  ap_session      *nat_aps;               /* proxy session */
 103         frentry_t       *nat_fr;        /* filter rule ptr if appropriate */
 104         struct  ipnat   *nat_ptr;       /* pointer back to the rule */
 105         void            *nat_ifps[2];
 106         void            *nat_sync;
 107         ipftqent_t      nat_tqe;
 108         u_32_t          nat_flags;
 109         u_32_t          nat_sumd[2];    /* ip checksum delta for data segment */
 110         u_32_t          nat_ipsumd;     /* ip checksum delta for ip header */
 111         u_32_t          nat_mssclamp;   /* if != zero clamp MSS to this */
 112         i6addr_t        nat_inip6;
 113         i6addr_t        nat_outip6;
 114         i6addr_t        nat_oip6;               /* other ip */
 115         U_QUAD_T        nat_pkts[2];
 116         U_QUAD_T        nat_bytes[2];
 117         union   {
 118                 udpinfo_t       nat_unu;
 119                 tcpinfo_t       nat_unt;
 120                 icmpinfo_t      nat_uni;
 121                 greinfo_t       nat_ugre;
 122         } nat_un;
 123         u_short         nat_oport;              /* other port */
 124         u_short         nat_use;
 125         u_char          nat_p;                  /* protocol for NAT */
 126         int             nat_dir;
 127         int             nat_ref;                /* reference count */
 128         int             nat_hv[2];
 129         char            nat_ifnames[2][LIFNAMSIZ];
 130         int             nat_rev;                /* 0 = forward, 1 = reverse */
 131         int             nat_v;
 132         int             nat_redir;              /* copy of in_redir */
 133 } nat_t;
 134
 135 #define nat_inip        nat_inip6.in4
 136 #define nat_outip       nat_outip6.in4
 137 #define nat_oip         nat_oip6.in4
 138 #define nat_age         nat_tqe.tqe_die
 139 #define nat_inport      nat_un.nat_unt.ts_sport
 140 #define nat_outport     nat_un.nat_unt.ts_dport
 141 #define nat_type        nat_un.nat_uni.ici_type
 142 #define nat_seq         nat_un.nat_uni.ici_seq
 143 #define nat_id          nat_un.nat_uni.ici_id
 144 #define nat_tcpstate    nat_tqe.tqe_state
 145
 146 /*
 147  * Values for nat_dir
 148  */
 149 #define NAT_INBOUND     0
 150 #define NAT_OUTBOUND    1
 151
 152 /*
 153  * Definitions for nat_flags
 154  */
 155 #define NAT_TCP         0x0001  /* IPN_TCP */
 156 #define NAT_UDP         0x0002  /* IPN_UDP */
 157 #define NAT_ICMPERR     0x0004  /* IPN_ICMPERR */
 158 #define NAT_ICMPQUERY   0x0008  /* IPN_ICMPQUERY */
 159 #define NAT_SEARCH      0x0010
 160 #define NAT_SLAVE       0x0020  /* Slave connection for a proxy */
 161 #define NAT_NOTRULEPORT 0x0040
 162
 163 #define NAT_TCPUDP      (NAT_TCP|NAT_UDP)
 164 #define NAT_TCPUDPICMP  (NAT_TCP|NAT_UDP|NAT_ICMPERR)
 165 #define NAT_TCPUDPICMPQ (NAT_TCP|NAT_UDP|NAT_ICMPQUERY)
 166 #define NAT_FROMRULE    (NAT_TCP|NAT_UDP)
 167
 168 /* 0x0100 reserved for FI_W_SPORT */
 169 /* 0x0200 reserved for FI_W_DPORT */
 170 /* 0x0400 reserved for FI_W_SADDR */
 171 /* 0x0800 reserved for FI_W_DADDR */
 172 /* 0x1000 reserved for FI_W_NEWFR */
 173 /* 0x2000 reserved for SI_CLONE */
 174 /* 0x4000 reserved for SI_CLONED */
 175 /* 0x8000 reserved for SI_IGNOREPKT */
 176
 177 #define NAT_DEBUG       0x800000
 178
 179 typedef struct  ipnat   {
 180         struct  ipnat   *in_next;               /* NAT rule list next */
 181         struct  ipnat   *in_rnext;              /* rdr rule hash next */
 182         struct  ipnat   **in_prnext;            /* prior rdr next ptr */
 183         struct  ipnat   *in_mnext;              /* map rule hash next */
 184         struct  ipnat   **in_pmnext;            /* prior map next ptr */
 185         struct  ipftq   *in_tqehead[2];
 186         void            *in_ifps[2];
 187         void            *in_apr;
 188         char            *in_comment;
 189         i6addr_t        in_next6;
 190         u_long          in_space;
 191         u_long          in_hits;
 192         u_int           in_use;
 193         u_int           in_hv;
 194         int             in_flineno;             /* conf. file line number */
 195         u_short         in_pnext;
 196         u_char          in_v;
 197         u_char          in_xxx;
 198         /* From here to the end is covered by IPN_CMPSIZ */
 199         u_32_t          in_flags;
 200         u_32_t          in_mssclamp;            /* if != 0 clamp MSS to this */
 201         u_int           in_age[2];
 202         int             in_redir;               /* see below for values */
 203         int             in_p;                   /* protocol. */
 204         i6addr_t        in_in[2];
 205         i6addr_t        in_out[2];
 206         i6addr_t        in_src[2];
 207         frtuc_t         in_tuc;
 208         u_short         in_port[2];
 209         u_short         in_ppip;                /* ports per IP. */
 210         u_short         in_ippip;               /* IP #'s per IP# */
 211         char            in_ifnames[2][LIFNAMSIZ];
 212         char            in_plabel[APR_LABELLEN];        /* proxy label. */
 213         ipftag_t        in_tag;
 214 } ipnat_t;
 215
 216 #define in_pmin         in_port[0]      /* Also holds static redir port */
 217 #define in_pmax         in_port[1]
 218 #define in_nextip       in_next6.in4
 219 #define in_nip          in_next6.in4.s_addr
 220 #define in_inip         in_in[0].in4.s_addr
 221 #define in_inmsk        in_in[1].in4.s_addr
 222 #define in_outip        in_out[0].in4.s_addr
 223 #define in_outmsk       in_out[1].in4.s_addr
 224 #define in_srcip        in_src[0].in4.s_addr
 225 #define in_srcmsk       in_src[1].in4.s_addr
 226 #define in_scmp         in_tuc.ftu_scmp
 227 #define in_dcmp         in_tuc.ftu_dcmp
 228 #define in_stop         in_tuc.ftu_stop
 229 #define in_dtop         in_tuc.ftu_dtop
 230 #define in_sport        in_tuc.ftu_sport
 231 #define in_dport        in_tuc.ftu_dport
 232
 233 /*
 234  * Bit definitions for in_flags
 235  */
 236 #define IPN_ANY         0x00000
 237 #define IPN_TCP         0x00001
 238 #define IPN_UDP         0x00002
 239 #define IPN_TCPUDP      (IPN_TCP|IPN_UDP)
 240 #define IPN_ICMPERR     0x00004
 241 #define IPN_TCPUDPICMP  (IPN_TCP|IPN_UDP|IPN_ICMPERR)
 242 #define IPN_ICMPQUERY   0x00008
 243 #define IPN_TCPUDPICMPQ (IPN_TCP|IPN_UDP|IPN_ICMPQUERY)
 244 #define IPN_RF          (IPN_TCPUDP|IPN_DELETE|IPN_ICMPERR)
 245 #define IPN_AUTOPORTMAP 0x00010
 246 #define IPN_IPRANGE     0x00020
 247 #define IPN_FILTER      0x00040
 248 #define IPN_SPLIT       0x00080
 249 #define IPN_ROUNDR      0x00100
 250 #define IPN_NOTSRC      0x04000
 251 #define IPN_NOTDST      0x08000
 252 #define IPN_DYNSRCIP    0x10000 /* dynamic src IP# */
 253 #define IPN_DYNDSTIP    0x20000 /* dynamic dst IP# */
 254 #define IPN_DELETE      0x40000
 255 #define IPN_STICKY      0x80000
 256 #define IPN_FRAG        0x100000
 257 #define IPN_FIXEDDPORT  0x200000
 258 #define IPN_FINDFORWARD 0x400000
 259 #define IPN_IN          0x800000
 260 #define IPN_SEQUENTIAL  0x1000000
 261 #define IPN_USERFLAGS   (IPN_TCPUDP|IPN_AUTOPORTMAP|IPN_IPRANGE|IPN_SPLIT|\
 262                          IPN_ROUNDR|IPN_FILTER|IPN_NOTSRC|IPN_NOTDST|\
 263                          IPN_FRAG|IPN_STICKY|IPN_FIXEDDPORT|IPN_ICMPQUERY|\
 264                          IPN_SEQUENTIAL)
 265
 266 /*
 267  * Values for in_redir
 268  */
 269 #define NAT_MAP         0x01
 270 #define NAT_REDIRECT    0x02
 271 #define NAT_BIMAP       (NAT_MAP|NAT_REDIRECT)
 272 #define NAT_MAPBLK      0x04
 273
 274 #define MAPBLK_MINPORT  1024    /* don't use reserved ports for src port */
 275 #define USABLE_PORTS    (65536 - MAPBLK_MINPORT)
 276
 277 #define IPN_CMPSIZ      (sizeof (ipnat_t) - offsetof(ipnat_t, in_flags))
 278
 279 typedef struct  natlookup {
 280         i6addr_t        nl_inipaddr;
 281         i6addr_t        nl_outipaddr;
 282         i6addr_t        nl_realipaddr;
 283         int             nl_v;
 284         int             nl_flags;
 285         u_short         nl_inport;
 286         u_short         nl_outport;
 287         u_short         nl_realport;
 288 } natlookup_t;
 289
 290 #define nl_inip         nl_inipaddr.in4
 291 #define nl_outip        nl_outipaddr.in4
 292 #define nl_realip       nl_realipaddr.in4
 293 #define nl_inip6        nl_inipaddr.in6
 294 #define nl_outip6       nl_outipaddr.in6
 295 #define nl_realip6      nl_realipaddr.in6
 296
 297
 298 typedef struct  nat_save    {
 299         void    *ipn_next;
 300         struct  nat     ipn_nat;
 301         struct  ipnat   ipn_ipnat;
 302         struct  frentry ipn_fr;
 303         int     ipn_dsize;
 304         char    ipn_data[4];
 305 } nat_save_t;
 306
 307 #define ipn_rule        ipn_nat.nat_fr
 308
 309 typedef struct  natget  {
 310         void    *ng_ptr;
 311         int     ng_sz;
 312 } natget_t;
 313
 314
 315 #undef  tr_flags
 316 typedef struct  nattrpnt        {
 317         struct  in_addr tr_dstip;       /* real destination IP# */
 318         struct  in_addr tr_srcip;       /* real source IP# */
 319         struct  in_addr tr_locip;       /* local source IP# */
 320         u_int   tr_flags;
 321         int     tr_expire;
 322         u_short tr_dstport;     /* real destination port# */
 323         u_short tr_srcport;     /* real source port# */
 324         u_short tr_locport;     /* local source port# */
 325         struct  nattrpnt        *tr_hnext;
 326         struct  nattrpnt        **tr_phnext;
 327         struct  nattrpnt        *tr_next;
 328         struct  nattrpnt        **tr_pnext;     /* previous next */
 329 } nattrpnt_t;
 330
 331 #define TN_CMPSIZ       offsetof(nattrpnt_t, tr_hnext)
 332
 333
 334 /*
 335  * This structure gets used to help NAT sessions keep the same NAT rule (and
 336  * thus translation for IP address) when:
 337  * (a) round-robin redirects are in use
 338  * (b) different IP add
 339  */
 340 typedef struct  hostmap {
 341         struct  hostmap *hm_next;
 342         struct  hostmap **hm_pnext;
 343         struct  hostmap *hm_hnext;
 344         struct  hostmap **hm_phnext;
 345         struct  ipnat   *hm_ipnat;
 346         i6addr_t        hm_src;
 347         i6addr_t        hm_dst;
 348         i6addr_t        hm_map;
 349         u_32_t          hm_port;
 350         int             hm_ref;
 351         int             hm_v;
 352 } hostmap_t;
 353
 354 #define hm_srcip        hm_src.in4
 355 #define hm_dstip        hm_dst.in4
 356 #define hm_mapip        hm_map.in4
 357 #define hm_srcip6       hm_src.in6
 358 #define hm_dstip6       hm_dst.in6
 359 #define hm_mapip6       hm_map.in6
 360
 361
 362 /*
 363  * Structure used to pass information in to nat_newmap and nat_newrdr.
 364  */
 365 typedef struct  natinfo {
 366         ipnat_t         *nai_np;
 367         u_32_t          nai_nflags;
 368         u_32_t          nai_flags;
 369         struct  in_addr nai_ip;
 370         u_short         nai_port;
 371         u_short         nai_nport;
 372         u_short         nai_sport;
 373         u_short         nai_dport;
 374 } natinfo_t;
 375
 376
 377 typedef struct  natstat {
 378         u_long  ns_mapped[2];
 379         u_long  ns_rules;
 380         u_long  ns_added;
 381         u_long  ns_expire;
 382         u_long  ns_inuse;
 383         u_long  ns_logged;
 384         u_long  ns_logfail;
 385         u_long  ns_memfail;
 386         u_long  ns_badnat;
 387         u_long  ns_addtrpnt;
 388         nat_t   **ns_table[2];
 389         hostmap_t **ns_maptable;
 390         ipnat_t *ns_list;
 391         void    *ns_apslist;
 392         u_int   ns_wilds;
 393         u_int   ns_nattab_sz;
 394         u_int   ns_nattab_max;
 395         u_int   ns_rultab_sz;
 396         u_int   ns_rdrtab_sz;
 397         u_int   ns_trpntab_sz;
 398         u_int   ns_hostmap_sz;
 399         nat_t   *ns_instances;
 400         nattrpnt_t *ns_trpntlist;
 401         hostmap_t *ns_maplist;
 402         u_long  *ns_bucketlen[2];
 403         u_int   ns_orphans;
 404         u_long  ns_uncreate[2][2];
 405 } natstat_t;
 406
 407 typedef struct  natlog {
 408         i6addr_t        nlg_origip;
 409         i6addr_t        nlg_outip;
 410         i6addr_t        nlg_inip;
 411         u_short         nlg_origport;
 412         u_short         nlg_outport;
 413         u_short         nlg_inport;
 414         u_short         nlg_type;
 415         int             nlg_rule;
 416         U_QUAD_T        nlg_pkts[2];
 417         U_QUAD_T        nlg_bytes[2];
 418         u_char          nlg_p;
 419         int             nlg_v;
 420 } natlog_t;
 421
 422
 423 #define NL_NEWMAP       NAT_MAP
 424 #define NL_NEWRDR       NAT_REDIRECT
 425 #define NL_NEWBIMAP     NAT_BIMAP
 426 #define NL_NEWBLOCK     NAT_MAPBLK
 427 #define NL_DESTROY      0xfffc
 428 #define NL_CLONE        0xfffd
 429 #define NL_FLUSH        0xfffe
 430 #define NL_EXPIRE       0xffff
 431
 432 #define NAT_HASH_FN(k, l, m)    (((k) + ((k) >> 12) + l) % (m))
 433 #define NAT_HASH_FN6(k, l, m)   ((((u_32_t *)(k))[3] \
 434                                 + (((u_32_t *)(k))[3] >> 12) \
 435                                 + (((u_32_t *)(k))[2]) \
 436                                 + (((u_32_t *)(k))[2] >> 12) \
 437                                 + (((u_32_t *)(k))[1]) \
 438                                 + (((u_32_t *)(k))[1] >> 12) \
 439                                 + (((u_32_t *)(k))[0]) \
 440                                 + (((u_32_t *)(k))[0] >> 12) \
 441                                 + l) % (m))
 442
 443 #define LONG_SUM(in)    (((in) & 0xffff) + ((in) >> 16))
 444 #define LONG_SUM6(in)   (LONG_SUM(ntohl(((u_32_t *)(in))[0])) + \
 445                          LONG_SUM(ntohl(((u_32_t *)(in))[1])) + \
 446                          LONG_SUM(ntohl(((u_32_t *)(in))[2])) + \
 447                          LONG_SUM(ntohl(((u_32_t *)(in))[3])))
 448
 449 #define CALC_SUMD(s1, s2, sd) { \
 450                             (s1) = ((s1) & 0xffff) + ((s1) >> 16); \
 451                             (s2) = ((s2) & 0xffff) + ((s2) >> 16); \
 452                             /* Do it twice */ \
 453                             (s1) = ((s1) & 0xffff) + ((s1) >> 16); \
 454                             (s2) = ((s2) & 0xffff) + ((s2) >> 16); \
 455                             /* Because ~1 == -2, We really need ~1 == -1 */ \
 456                             if ((s1) > (s2)) (s2)--; \
 457                             (sd) = (s2) - (s1); \
 458                             (sd) = ((sd) & 0xffff) + ((sd) >> 16); }
 459
 460 #define NAT_SYSSPACE            0x80000000
 461 #define NAT_LOCKHELD            0x40000000
 462
 463 extern  void    fr_natsync __P((void *, ipf_stack_t *));
 464 extern  void    fr_nataddrsync __P((int, void *, void *, ipf_stack_t *));
 465 extern  void    fr_natifpsync __P((int, int, void *, char *, ipf_stack_t *));
 466
 467 #if defined(__OpenBSD__)
 468 extern  void    nat_ifdetach __P((void *, ipf_stack_t *));
 469 #endif
 470 extern  int     fr_nat_ioctl __P((caddr_t, ioctlcmd_t, int, int, void *, ipf_stack_t *));
 471 extern  int     fr_natinit __P((ipf_stack_t *));
 472 extern  nat_t   *nat_new __P((fr_info_t *, ipnat_t *, nat_t **, u_int, int));
 473 extern  nat_t   *nat_outlookup __P((fr_info_t *, u_int, u_int, struct in_addr,
 474                                  struct in_addr));
 475 extern  void    fix_datacksum __P((u_short *, u_32_t));
 476 extern  nat_t   *nat_inlookup __P((fr_info_t *, u_int, u_int, struct in_addr,
 477                                 struct in_addr));
 478 extern  nat_t   *nat_tnlookup __P((fr_info_t *, int));
 479 extern  nat_t   *nat_maplookup __P((void *, u_int, struct in_addr,
 480                                 struct in_addr));
 481 extern  nat_t   *nat_lookupredir __P((natlookup_t *, ipf_stack_t *));
 482 extern  nat_t   *nat_icmperrorlookup __P((fr_info_t *, int));
 483 extern  nat_t   *nat_icmperror __P((fr_info_t *, u_int *, int));
 484 extern  int     nat_delete __P((struct nat *, int, ipf_stack_t *));
 485 extern  int     nat_insert __P((nat_t *, int, ipf_stack_t *));
 486
 487 extern  int     fr_checknatout __P((fr_info_t *, u_32_t *));
 488 extern  int     fr_natout __P((fr_info_t *, nat_t *, int, u_32_t));
 489 extern  int     fr_checknatin __P((fr_info_t *, u_32_t *));
 490 extern  int     fr_natin __P((fr_info_t *, nat_t *, int, u_32_t));
 491 extern  void    fr_natunload __P((ipf_stack_t *));
 492 extern  void    nat_uncreate __P((fr_info_t *));
 493 extern  void    fr_natexpire __P((ipf_stack_t *));
 494 extern  void    nat_log __P((struct nat *, u_int, ipf_stack_t *));
 495 extern  void    fix_incksum __P((u_short *, u_32_t));
 496 extern  void    fix_outcksum __P((u_short *, u_32_t));
 497 extern  void    fr_ipnatderef __P((ipnat_t **, ipf_stack_t *));
 498 extern  void    fr_natderef __P((nat_t **, ipf_stack_t *));
 499 extern  u_short *nat_proto __P((fr_info_t *, nat_t *, u_int));
 500 extern  void    nat_update __P((fr_info_t *, nat_t *, ipnat_t *));
 501 extern  void    fr_setnatqueue __P((nat_t *, int, ipf_stack_t *));
 502 extern  void    fr_hostmapdel __P((hostmap_t **));
 503 #if SOLARIS2 >= 10
 504 extern  void    fr_natifindexsync __P((void *, void *, ipf_stack_t *));
 505 #endif
 506
 507 extern  nat_t   *fr_natclone __P((fr_info_t *, nat_t *));
 508 extern  void    nat_delrdr __P((struct ipnat *));
 509 extern  void    nat_delnat __P((struct ipnat *));
 510 extern  int     nat_wildok __P((nat_t *, int, int, int, int));
 511 extern  void    nat_calc_chksum_diffs __P((nat_t *));
 512
 513 #ifdef  USE_INET6
 514 extern  void    nat6_addnat __P((ipnat_t *, ipf_stack_t *));
 515 extern  void    nat6_addrdr __P((ipnat_t *, ipf_stack_t *));
 516 extern  nat_t   *nat6_new __P((fr_info_t *, ipnat_t *, nat_t **, u_int, int));
 517 extern  nat_t   *nat6_outlookup __P((fr_info_t *, u_int, u_int,
 518                                 struct in6_addr *, struct in6_addr *));
 519 extern  nat_t   *nat6_inlookup __P((fr_info_t *, u_int, u_int,
 520                                 struct in6_addr *, struct in6_addr *));
 521 extern  nat_t   *nat6_lookupredir __P((natlookup_t *, ipf_stack_t *));
 522 extern  nat_t   *nat6_icmperrorlookup __P((fr_info_t *, int));
 523 extern  nat_t   *nat6_icmperror __P((fr_info_t *, u_int *, int));
 524 extern  int     nat6_insert __P((nat_t *, int, ipf_stack_t *));
 525 extern  int     fr_checknat6out __P((fr_info_t *, u_32_t *));
 526 extern  int     fr_nat6out __P((fr_info_t *, nat_t *, int, u_32_t));
 527 extern  int     fr_checknat6in __P((fr_info_t *, u_32_t *));
 528 extern  int     fr_nat6in __P((fr_info_t *, nat_t *, int, u_32_t));
 529 #endif
 530
 531 #endif /* __IP_NAT_H__ */