/* * Copyright (C) 1995-2003 by Darren Reed. * * See the IPFILTER.LICENCE file for details on licencing. * * Copyright 2008 Sun Microsystems, Inc. All rights reserved. * Use is subject to license terms. */ #pragma ident "%Z%%M% %I% %E% SMI"$ #if defined(KERNEL) || defined(_KERNEL) # undef KERNEL # undef _KERNEL # define KERNEL 1 # define _KERNEL 1 #endif #include #include #include #include #include #if defined(__NetBSD__) && (NetBSD >= 199905) && !defined(IPFILTER_LKM) && \ defined(_KERNEL) # include "opt_ipfilter_log.h" #endif #if !defined(_KERNEL) # include # include # include # define _KERNEL # ifdef __OpenBSD__ struct file; # endif # include # undef _KERNEL #endif #if defined(_KERNEL) && (__FreeBSD_version >= 220000) # include # include #else # include #endif #if !defined(AIX) # include #endif #if !defined(linux) # include #endif #include #if defined(_KERNEL) # include # if !defined(__SVR4) && !defined(__svr4__) # include # endif #endif #if defined(__SVR4) || defined(__svr4__) # include # include # ifdef _KERNEL # include # endif # include # include #endif #if __FreeBSD_version >= 300000 # include #endif #include #if __FreeBSD_version >= 300000 # include # if defined(_KERNEL) && !defined(IPFILTER_LKM) # include "opt_ipfilter.h" # endif #endif #ifdef sun # include #endif #include #include #include #include #ifdef RFC1825 # include # include extern struct ifnet vpnif; #endif #if !defined(linux) # include #endif #include #include #include #include "netinet/ip_compat.h" #include #include "netinet/ip_fil.h" #include "netinet/ip_nat.h" #include "netinet/ip_frag.h" #include "netinet/ip_state.h" #include "netinet/ip_proxy.h" #include "netinet/ipf_stack.h" #ifdef IPFILTER_SYNC #include "netinet/ip_sync.h" #endif #if (__FreeBSD_version >= 300000) # include #endif /* END OF INCLUDES */ #undef SOCKADDR_IN #define SOCKADDR_IN struct sockaddr_in #if !defined(lint) static const char rcsid[] = "@(#)$Id: ip_nat6.c,v 1.2 2008/02/14 21:05:50 darrenr Exp $"; #endif static hostmap_t *nat6_hostmap __P((ipnat_t *, i6addr_t *, i6addr_t *, i6addr_t *, u_32_t, ipf_stack_t *)); static INLINE int nat6_newmap __P((fr_info_t *, nat_t *, natinfo_t *)); static INLINE int nat6_newrdr __P((fr_info_t *, nat_t *, natinfo_t *)); static INLINE int nat6_finalise __P((fr_info_t *, nat_t *, natinfo_t *, tcphdr_t *, nat_t **, int)); static void nat6_tabmove __P((nat_t *, ipf_stack_t *)); static int nat6_match __P((fr_info_t *, ipnat_t *)); static INLINE int nat_icmpquerytype6 __P((int)); /* ------------------------------------------------------------------------ */ /* Function: nat6_addrdr */ /* Returns: Nil */ /* Parameters: n(I) - pointer to NAT rule to add */ /* */ /* Adds a redirect rule to the hash table of redirect rules and the list of */ /* loaded NAT rules. Updates the bitmask indicating which netmasks are in */ /* use by redirect rules. */ /* ------------------------------------------------------------------------ */ void nat6_addrdr(n, ifs) ipnat_t *n; ipf_stack_t *ifs; { ipnat_t **np; i6addr_t j; u_int hv; int k; k = count6bits(n->in_out[1].i6); if ((k >= 0) && (k != 128)) ifs->ifs_rdr6_masks[k >> 5] |= 1 << (k & 31); IP6_AND(&n->in_out[0], &n->in_out[1], &j); hv = NAT_HASH_FN6(&j, 0, ifs->ifs_ipf_rdrrules_sz); np = ifs->ifs_rdr_rules + hv; while (*np != NULL) np = &(*np)->in_rnext; n->in_rnext = NULL; n->in_prnext = np; n->in_hv = hv; *np = n; } /* ------------------------------------------------------------------------ */ /* Function: nat6_addnat */ /* Returns: Nil */ /* Parameters: n(I) - pointer to NAT rule to add */ /* */ /* Adds a NAT map rule to the hash table of rules and the list of loaded */ /* NAT rules. Updates the bitmask indicating which netmasks are in use by */ /* redirect rules. */ /* ------------------------------------------------------------------------ */ void nat6_addnat(n, ifs) ipnat_t *n; ipf_stack_t *ifs; { ipnat_t **np; i6addr_t j; u_int hv; int k; k = count6bits(n->in_in[1].i6); if ((k >= 0) && (k != 128)) ifs->ifs_nat6_masks[k >> 5] |= 1 << (k & 31); IP6_AND(&n->in_in[0], &n->in_in[1], &j); hv = NAT_HASH_FN6(&j, 0, ifs->ifs_ipf_natrules_sz); np = ifs->ifs_nat_rules + hv; while (*np != NULL) np = &(*np)->in_mnext; n->in_mnext = NULL; n->in_pmnext = np; n->in_hv = hv; *np = n; } /* ------------------------------------------------------------------------ */ /* Function: nat6_hostmap */ /* Returns: struct hostmap* - NULL if no hostmap could be created, */ /* else a pointer to the hostmapping to use */ /* Parameters: np(I) - pointer to NAT rule */ /* real(I) - real IP address */ /* map(I) - mapped IP address */ /* port(I) - destination port number */ /* Write Locks: ipf_nat */ /* */ /* Check if an ip address has already been allocated for a given mapping */ /* that is not doing port based translation. If is not yet allocated, then */ /* create a new entry if a non-NULL NAT rule pointer has been supplied. */ /* ------------------------------------------------------------------------ */ static struct hostmap *nat6_hostmap(np, src, dst, map, port, ifs) ipnat_t *np; i6addr_t *src, *dst, *map; u_32_t port; ipf_stack_t *ifs; { hostmap_t *hm; u_int hv; hv = (src->i6[3] ^ dst->i6[3]); hv += (src->i6[2] ^ dst->i6[2]); hv += (src->i6[1] ^ dst->i6[1]); hv += (src->i6[0] ^ dst->i6[0]); hv += src->i6[3]; hv += src->i6[2]; hv += src->i6[1]; hv += src->i6[0]; hv += dst->i6[3]; hv += dst->i6[2]; hv += dst->i6[1]; hv += dst->i6[0]; hv %= HOSTMAP_SIZE; for (hm = ifs->ifs_maptable[hv]; hm; hm = hm->hm_next) if (IP6_EQ(&hm->hm_srcip6, src) && IP6_EQ(&hm->hm_dstip6, dst) && ((np == NULL) || (np == hm->hm_ipnat)) && ((port == 0) || (port == hm->hm_port))) { hm->hm_ref++; return hm; } if (np == NULL) return NULL; KMALLOC(hm, hostmap_t *); if (hm) { hm->hm_hnext = ifs->ifs_ipf_hm_maplist; hm->hm_phnext = &ifs->ifs_ipf_hm_maplist; if (ifs->ifs_ipf_hm_maplist != NULL) ifs->ifs_ipf_hm_maplist->hm_phnext = &hm->hm_hnext; ifs->ifs_ipf_hm_maplist = hm; hm->hm_next = ifs->ifs_maptable[hv]; hm->hm_pnext = ifs->ifs_maptable + hv; if (ifs->ifs_maptable[hv] != NULL) ifs->ifs_maptable[hv]->hm_pnext = &hm->hm_next; ifs->ifs_maptable[hv] = hm; hm->hm_ipnat = np; hm->hm_src = *src; hm->hm_dst = *dst; hm->hm_map = *map; hm->hm_ref = 1; hm->hm_port = port; hm->hm_v = 6; } return hm; } /* ------------------------------------------------------------------------ */ /* Function: nat6_newmap */ /* Returns: int - -1 == error, 0 == success */ /* Parameters: fin(I) - pointer to packet information */ /* nat(I) - pointer to NAT entry */ /* ni(I) - pointer to structure with misc. information needed */ /* to create new NAT entry. */ /* */ /* Given an empty NAT structure, populate it with new information about a */ /* new NAT session, as defined by the matching NAT rule. */ /* ni.nai_ip is passed in uninitialised and must be set, in host byte order,*/ /* to the new IP address for the translation. */ /* ------------------------------------------------------------------------ */ static INLINE int nat6_newmap(fin, nat, ni) fr_info_t *fin; nat_t *nat; natinfo_t *ni; { u_short st_port, dport, sport, port, sp, dp; i6addr_t in, st_ip; hostmap_t *hm; u_32_t flags; ipnat_t *np; nat_t *natl; int l; ipf_stack_t *ifs = fin->fin_ifs; /* * If it's an outbound packet which doesn't match any existing * record, then create a new port */ l = 0; hm = NULL; np = ni->nai_np; st_ip = np->in_next6; st_port = np->in_pnext; flags = ni->nai_flags; sport = ni->nai_sport; dport = ni->nai_dport; /* * Do a loop until we either run out of entries to try or we find * a NAT mapping that isn't currently being used. This is done * because the change to the source is not (usually) being fixed. */ do { port = 0; in = np->in_next6; if (l == 0) { /* * Check to see if there is an existing NAT * setup for this IP address pair. */ hm = nat6_hostmap(np, &fin->fin_src6, &fin->fin_dst6, &in, 0, ifs); if (hm != NULL) in = hm->hm_map; } else if ((l == 1) && (hm != NULL)) { fr_hostmapdel(&hm); } nat->nat_hm = hm; if (IP6_ISONES(&np->in_out[1]) && (np->in_pnext == 0)) { if (l > 0) return -1; } if (np->in_redir == NAT_BIMAP && IP6_EQ(&np->in_in[1], &np->in_out[1])) { i6addr_t temp; /* * map the address block in a 1:1 fashion */ temp.i6[0] = fin->fin_src6.i6[0] & ~np->in_in[1].i6[0]; temp.i6[1] = fin->fin_src6.i6[1] & ~np->in_in[1].i6[1]; temp.i6[2] = fin->fin_src6.i6[2] & ~np->in_in[1].i6[2]; temp.i6[3] = fin->fin_src6.i6[3] & ~np->in_in[1].i6[3]; in = np->in_out[0]; IP6_MERGE(&in, &temp, &np->in_in[0]); #ifdef NEED_128BIT_MATH } else if (np->in_redir & NAT_MAPBLK) { if ((l >= np->in_ppip) || ((l > 0) && !(flags & IPN_TCPUDP))) return -1; /* * map-block - Calculate destination address. */ IP6_MASK(&in, &fin->fin_src6, &np->in_in[1]); in = ntol(in); inb = in; in /= np->in_ippip; in &= ntohl(~np->in_out[1]); in += ntohl(np->in_out[0]); /* * Calculate destination port. */ if ((flags & IPN_TCPUDP) && (np->in_ppip != 0)) { port = ntohs(sport) + l; port %= np->in_ppip; port += np->in_ppip * (inb.s_addr % np->in_ippip); port += MAPBLK_MINPORT; port = htons(port); } #endif } else if (IP6_ISZERO(&np->in_out[0]) && IP6_ISONES(&np->in_out[1])) { /* * 0/128 - use the interface's IP address. */ if ((l > 0) || fr_ifpaddr(6, FRI_NORMAL, fin->fin_ifp, (void *)&in, NULL, fin->fin_ifs) == -1) return -1; } else if (IP6_ISZERO(&np->in_out[0]) && IP6_ISZERO(&np->in_out[1])) { /* * 0/0 - use the original source address/port. */ if (l > 0) return -1; in = fin->fin_src6; } else if (!IP6_ISONES(&np->in_out[1]) && (np->in_pnext == 0) && ((l > 0) || (hm == NULL))) { IP6_INC(&np->in_next6); } natl = NULL; if ((flags & IPN_TCPUDP) && ((np->in_redir & NAT_MAPBLK) == 0) && (np->in_flags & IPN_AUTOPORTMAP)) { /*EMPTY*/; #ifdef NEED_128BIT_MATH /* * XXX "ports auto" (without map-block) */ if ((l > 0) && (l % np->in_ppip == 0)) { if (l > np->in_space) { return -1; } else if ((l > np->in_ppip) && !IP6_ISONES(&np->in_out[1])) { IP6_INC(&np->in_next6); } } if (np->in_ppip != 0) { port = ntohs(sport); port += (l % np->in_ppip); port %= np->in_ppip; port += np->in_ppip * (ntohl(fin->fin_src6) % np->in_ippip); port += MAPBLK_MINPORT; port = htons(port); } #endif } else if (((np->in_redir & NAT_MAPBLK) == 0) && (flags & IPN_TCPUDPICMP) && (np->in_pnext != 0)) { /* * Standard port translation. Select next port. */ if (np->in_flags & IPN_SEQUENTIAL) { port = np->in_pnext; } else { port = ipf_random() % (ntohs(np->in_pmax) - ntohs(np->in_pmin)); port += ntohs(np->in_pmin); } port = htons(port); np->in_pnext++; if (np->in_pnext > ntohs(np->in_pmax)) { np->in_pnext = ntohs(np->in_pmin); if (!IP6_ISONES(&np->in_out[1])) { IP6_INC(&np->in_next6); } } } if (np->in_flags & IPN_IPRANGE) { if (IP6_GT(&np->in_next6, &np->in_out[1])) np->in_next6 = np->in_out[0]; } else { i6addr_t a1, a2; a1 = np->in_next6; IP6_INC(&a1); IP6_AND(&a1, &np->in_out[1], &a2); if (!IP6_ISONES(&np->in_out[1]) && IP6_GT(&a2, &np->in_out[0])) { IP6_ADD(&np->in_out[0], 1, &np->in_next6); } } if ((port == 0) && (flags & (IPN_TCPUDPICMP|IPN_ICMPQUERY))) port = sport; /* * Here we do a lookup of the connection as seen from * the outside. If an IP# pair already exists, try * again. So if you have A->B becomes C->B, you can * also have D->E become C->E but not D->B causing * another C->B. Also take protocol and ports into * account when determining whether a pre-existing * NAT setup will cause an external conflict where * this is appropriate. */ sp = fin->fin_data[0]; dp = fin->fin_data[1]; fin->fin_data[0] = fin->fin_data[1]; fin->fin_data[1] = htons(port); natl = nat6_inlookup(fin, flags & ~(SI_WILDP|NAT_SEARCH), (u_int)fin->fin_p, &fin->fin_dst6.in6, &in.in6); fin->fin_data[0] = sp; fin->fin_data[1] = dp; /* * Has the search wrapped around and come back to the * start ? */ if ((natl != NULL) && (np->in_pnext != 0) && (st_port == np->in_pnext) && !IP6_ISZERO(&np->in_next6) && IP6_EQ(&st_ip, &np->in_next6)) return -1; l++; } while (natl != NULL); if (np->in_space > 0) np->in_space--; /* Setup the NAT table */ nat->nat_inip6 = fin->fin_src6; nat->nat_outip6 = in; nat->nat_oip6 = fin->fin_dst6; if (nat->nat_hm == NULL) nat->nat_hm = nat6_hostmap(np, &fin->fin_src6, &fin->fin_dst6, &nat->nat_outip6, 0, ifs); if (flags & IPN_TCPUDP) { nat->nat_inport = sport; nat->nat_outport = port; /* sport */ nat->nat_oport = dport; ((tcphdr_t *)fin->fin_dp)->th_sport = port; } else if (flags & IPN_ICMPQUERY) { ((struct icmp6_hdr *)fin->fin_dp)->icmp6_id = port; nat->nat_inport = port; nat->nat_outport = port; } ni->nai_port = port; ni->nai_nport = dport; return 0; } /* ------------------------------------------------------------------------ */ /* Function: nat6_newrdr */ /* Returns: int - -1 == error, 0 == success (no move), 1 == success and */ /* allow rule to be moved if IPN_ROUNDR is set. */ /* Parameters: fin(I) - pointer to packet information */ /* nat(I) - pointer to NAT entry */ /* ni(I) - pointer to structure with misc. information needed */ /* to create new NAT entry. */ /* */ /* ni.nai_ip is passed in uninitialised and must be set, in host byte order,*/ /* to the new IP address for the translation. */ /* ------------------------------------------------------------------------ */ static INLINE int nat6_newrdr(fin, nat, ni) fr_info_t *fin; nat_t *nat; natinfo_t *ni; { u_short nport, dport, sport; i6addr_t in; u_short sp, dp; hostmap_t *hm; u_32_t flags; ipnat_t *np; nat_t *natl; int move; ipf_stack_t *ifs = fin->fin_ifs; move = 1; hm = NULL; in.i6[0] = 0; in.i6[1] = 0; in.i6[2] = 0; in.i6[3] = 0; np = ni->nai_np; flags = ni->nai_flags; sport = ni->nai_sport; dport = ni->nai_dport; /* * If the matching rule has IPN_STICKY set, then we want to have the * same rule kick in as before. Why would this happen? If you have * a collection of rdr rules with "round-robin sticky", the current * packet might match a different one to the previous connection but * we want the same destination to be used. */ if ((np->in_flags & (IPN_ROUNDR|IPN_STICKY)) == (IPN_ROUNDR|IPN_STICKY)) { hm = nat6_hostmap(NULL, &fin->fin_src6, &fin->fin_dst6, &in, (u_32_t)dport, ifs); if (hm != NULL) { in = hm->hm_map; np = hm->hm_ipnat; ni->nai_np = np; move = 0; } } /* * Otherwise, it's an inbound packet. Most likely, we don't * want to rewrite source ports and source addresses. Instead, * we want to rewrite to a fixed internal address and fixed * internal port. */ if (np->in_flags & IPN_SPLIT) { in = np->in_next6; if ((np->in_flags & (IPN_ROUNDR|IPN_STICKY)) == IPN_STICKY) { hm = nat6_hostmap(np, &fin->fin_src6, &fin->fin_dst6, &in, (u_32_t)dport, ifs); if (hm != NULL) { in = hm->hm_map; move = 0; } } if (hm == NULL || hm->hm_ref == 1) { if (IP6_EQ(&np->in_in[0], &in)) { np->in_next6 = np->in_in[1]; move = 0; } else { np->in_next6 = np->in_in[0]; } } } else if (IP6_ISZERO(&np->in_in[0]) && IP6_ISONES(&np->in_in[1])) { /* * 0/128 - use the interface's IP address. */ if (fr_ifpaddr(6, FRI_NORMAL, fin->fin_ifp, (void *)&in, NULL, fin->fin_ifs) == -1) return -1; } else if (IP6_ISZERO(&np->in_in[0]) && IP6_ISZERO(&np->in_in[1])) { /* * 0/0 - use the original destination address/port. */ in = fin->fin_dst6; } else if (np->in_redir == NAT_BIMAP && IP6_EQ(&np->in_in[1], &np->in_out[1])) { i6addr_t temp; /* * map the address block in a 1:1 fashion */ temp.i6[0] = fin->fin_dst6.i6[0] & ~np->in_in[1].i6[0]; temp.i6[1] = fin->fin_dst6.i6[1] & ~np->in_in[1].i6[1]; temp.i6[2] = fin->fin_dst6.i6[2] & ~np->in_in[1].i6[2]; temp.i6[3] = fin->fin_dst6.i6[3] & ~np->in_in[1].i6[3]; in = np->in_in[0]; IP6_MERGE(&in, &temp, &np->in_in[1]); } else { in = np->in_in[0]; } if ((np->in_pnext == 0) || ((flags & NAT_NOTRULEPORT) != 0)) nport = dport; else { /* * Whilst not optimized for the case where * pmin == pmax, the gain is not significant. */ if (((np->in_flags & IPN_FIXEDDPORT) == 0) && (np->in_pmin != np->in_pmax)) { nport = ntohs(dport) - ntohs(np->in_pmin) + ntohs(np->in_pnext); nport = htons(nport); } else nport = np->in_pnext; } /* * When the redirect-to address is set to 0.0.0.0, just * assume a blank `forwarding' of the packet. We don't * setup any translation for this either. */ if (IP6_ISZERO(&in)) { if (nport == dport) return -1; in = fin->fin_dst6; } /* * Check to see if this redirect mapping already exists and if * it does, return "failure" (allowing it to be created will just * cause one or both of these "connections" to stop working.) */ sp = fin->fin_data[0]; dp = fin->fin_data[1]; fin->fin_data[1] = fin->fin_data[0]; fin->fin_data[0] = ntohs(nport); natl = nat6_outlookup(fin, flags & ~(SI_WILDP|NAT_SEARCH), (u_int)fin->fin_p, &in.in6, &fin->fin_src6.in6); fin->fin_data[0] = sp; fin->fin_data[1] = dp; if (natl != NULL) return -1; nat->nat_inip6 = in; nat->nat_outip6 = fin->fin_dst6; nat->nat_oip6 = fin->fin_src6; if ((nat->nat_hm == NULL) && ((np->in_flags & IPN_STICKY) != 0)) nat->nat_hm = nat6_hostmap(np, &fin->fin_src6, &fin->fin_dst6, &in, (u_32_t)dport, ifs); ni->nai_nport = nport; ni->nai_port = sport; if (flags & IPN_TCPUDP) { nat->nat_inport = nport; nat->nat_outport = dport; nat->nat_oport = sport; ((tcphdr_t *)fin->fin_dp)->th_dport = nport; } else if (flags & IPN_ICMPQUERY) { ((struct icmp6_hdr *)fin->fin_dp)->icmp6_id = nport; nat->nat_inport = nport; nat->nat_outport = nport; } return move; } /* ------------------------------------------------------------------------ */ /* Function: nat6_new */ /* Returns: nat_t* - NULL == failure to create new NAT structure, */ /* else pointer to new NAT structure */ /* Parameters: fin(I) - pointer to packet information */ /* np(I) - pointer to NAT rule */ /* natsave(I) - pointer to where to store NAT struct pointer */ /* flags(I) - flags describing the current packet */ /* direction(I) - direction of packet (in/out) */ /* Write Lock: ipf_nat */ /* */ /* Attempts to create a new NAT entry. Does not actually change the packet */ /* in any way. */ /* */ /* This fucntion is in three main parts: (1) deal with creating a new NAT */ /* structure for a "MAP" rule (outgoing NAT translation); (2) deal with */ /* creating a new NAT structure for a "RDR" rule (incoming NAT translation) */ /* and (3) building that structure and putting it into the NAT table(s). */ /* ------------------------------------------------------------------------ */ nat_t *nat6_new(fin, np, natsave, flags, direction) fr_info_t *fin; ipnat_t *np; nat_t **natsave; u_int flags; int direction; { tcphdr_t *tcp = NULL; hostmap_t *hm = NULL; nat_t *nat, *natl; u_int nflags; natinfo_t ni; int move; ipf_stack_t *ifs = fin->fin_ifs; /* * Trigger automatic call to nat_extraflush() if the * table has reached capcity specified by hi watermark. */ if (NAT_TAB_WATER_LEVEL(ifs) > ifs->ifs_nat_flush_lvl_hi) ifs->ifs_nat_doflush = 1; if (ifs->ifs_nat_stats.ns_inuse >= ifs->ifs_ipf_nattable_max) { ifs->ifs_nat_stats.ns_memfail++; return NULL; } move = 1; nflags = np->in_flags & flags; nflags &= NAT_FROMRULE; ni.nai_np = np; ni.nai_nflags = nflags; ni.nai_flags = flags; /* Give me a new nat */ KMALLOC(nat, nat_t *); if (nat == NULL) { ifs->ifs_nat_stats.ns_memfail++; /* * Try to automatically tune the max # of entries in the * table allowed to be less than what will cause kmem_alloc() * to fail and try to eliminate panics due to out of memory * conditions arising. */ if (ifs->ifs_ipf_nattable_max > ifs->ifs_ipf_nattable_sz) { ifs->ifs_ipf_nattable_max = ifs->ifs_nat_stats.ns_inuse - 100; printf("ipf_nattable_max reduced to %d\n", ifs->ifs_ipf_nattable_max); } return NULL; } if (flags & IPN_TCPUDP) { tcp = fin->fin_dp; ni.nai_sport = htons(fin->fin_sport); ni.nai_dport = htons(fin->fin_dport); } else if (flags & IPN_ICMPQUERY) { /* * In the ICMP query NAT code, we translate the ICMP id fields * to make them unique. This is indepedent of the ICMP type * (e.g. in the unlikely event that a host sends an echo and * an tstamp request with the same id, both packets will have * their ip address/id field changed in the same way). * * The icmp_id field is used by the sender to identify the * process making the icmp request. (the receiver justs * copies it back in its response). So, it closely matches * the concept of source port. We overlay sport, so we can * maximally reuse the existing code. */ ni.nai_sport = ((struct icmp6_hdr *)fin->fin_dp)->icmp6_id; ni.nai_dport = ni.nai_sport; } bzero((char *)nat, sizeof (*nat)); nat->nat_flags = flags; nat->nat_redir = np->in_redir; if ((flags & NAT_SLAVE) == 0) { MUTEX_ENTER(&ifs->ifs_ipf_nat_new); } /* * Search the current table for a match. */ if (direction == NAT_OUTBOUND) { /* * We can now arrange to call this for the same connection * because ipf_nat_new doesn't protect the code path into * this function. */ natl = nat6_outlookup(fin, nflags, (u_int)fin->fin_p, &fin->fin_src6.in6, &fin->fin_dst6.in6); if (natl != NULL) { KFREE(nat); nat = natl; goto done; } move = nat6_newmap(fin, nat, &ni); if (move == -1) goto badnat; np = ni.nai_np; } else { /* * NAT_INBOUND is used only for redirects rules */ natl = nat6_inlookup(fin, nflags, (u_int)fin->fin_p, &fin->fin_src6.in6, &fin->fin_dst6.in6); if (natl != NULL) { KFREE(nat); nat = natl; goto done; } move = nat6_newrdr(fin, nat, &ni); if (move == -1) goto badnat; np = ni.nai_np; } if ((move == 1) && (np->in_flags & IPN_ROUNDR)) { if (np->in_redir == NAT_REDIRECT) { nat_delrdr(np); nat6_addrdr(np, ifs); } else if (np->in_redir == NAT_MAP) { nat_delnat(np); nat6_addnat(np, ifs); } } if (nat6_finalise(fin, nat, &ni, tcp, natsave, direction) == -1) { goto badnat; } nat_calc_chksum_diffs(nat); if (flags & SI_WILDP) ifs->ifs_nat_stats.ns_wilds++; goto done; badnat: ifs->ifs_nat_stats.ns_badnat++; if ((hm = nat->nat_hm) != NULL) fr_hostmapdel(&hm); KFREE(nat); nat = NULL; done: if ((flags & NAT_SLAVE) == 0) { MUTEX_EXIT(&ifs->ifs_ipf_nat_new); } return nat; } /* ------------------------------------------------------------------------ */ /* Function: nat6_finalise */ /* Returns: int - 0 == sucess, -1 == failure */ /* Parameters: fin(I) - pointer to packet information */ /* nat(I) - pointer to NAT entry */ /* ni(I) - pointer to structure with misc. information needed */ /* to create new NAT entry. */ /* Write Lock: ipf_nat */ /* */ /* This is the tail end of constructing a new NAT entry and is the same */ /* for both IPv4 and IPv6. */ /* ------------------------------------------------------------------------ */ /*ARGSUSED*/ static INLINE int nat6_finalise(fin, nat, ni, tcp, natsave, direction) fr_info_t *fin; nat_t *nat; natinfo_t *ni; tcphdr_t *tcp; nat_t **natsave; int direction; { frentry_t *fr; ipnat_t *np; ipf_stack_t *ifs = fin->fin_ifs; np = ni->nai_np; COPYIFNAME(fin->fin_ifp, nat->nat_ifnames[0], fin->fin_v); #ifdef IPFILTER_SYNC if ((nat->nat_flags & SI_CLONE) == 0) nat->nat_sync = ipfsync_new(SMC_NAT, fin, nat); #endif nat->nat_me = natsave; nat->nat_dir = direction; nat->nat_ifps[0] = np->in_ifps[0]; nat->nat_ifps[1] = np->in_ifps[1]; nat->nat_ptr = np; nat->nat_p = fin->fin_p; nat->nat_v = fin->fin_v; nat->nat_mssclamp = np->in_mssclamp; fr = fin->fin_fr; nat->nat_fr = fr; nat->nat_v = 6; #ifdef IPF_V6_PROXIES if ((np->in_apr != NULL) && ((ni->nai_flags & NAT_SLAVE) == 0)) if (appr_new(fin, nat) == -1) return -1; #endif if (nat6_insert(nat, fin->fin_rev, ifs) == 0) { if (ifs->ifs_nat_logging) nat_log(nat, (u_int)np->in_redir, ifs); np->in_use++; if (fr != NULL) { MUTEX_ENTER(&fr->fr_lock); fr->fr_ref++; MUTEX_EXIT(&fr->fr_lock); } return 0; } /* * nat6_insert failed, so cleanup time... */ return -1; } /* ------------------------------------------------------------------------ */ /* Function: nat6_insert */ /* Returns: int - 0 == sucess, -1 == failure */ /* Parameters: nat(I) - pointer to NAT structure */ /* rev(I) - flag indicating forward/reverse direction of packet */ /* Write Lock: ipf_nat */ /* */ /* Insert a NAT entry into the hash tables for searching and add it to the */ /* list of active NAT entries. Adjust global counters when complete. */ /* ------------------------------------------------------------------------ */ int nat6_insert(nat, rev, ifs) nat_t *nat; int rev; ipf_stack_t *ifs; { u_int hv1, hv2; nat_t **natp; /* * Try and return an error as early as possible, so calculate the hash * entry numbers first and then proceed. */ if ((nat->nat_flags & (SI_W_SPORT|SI_W_DPORT)) == 0) { hv1 = NAT_HASH_FN6(&nat->nat_inip6, nat->nat_inport, 0xffffffff); hv1 = NAT_HASH_FN6(&nat->nat_oip6, hv1 + nat->nat_oport, ifs->ifs_ipf_nattable_sz); hv2 = NAT_HASH_FN6(&nat->nat_outip6, nat->nat_outport, 0xffffffff); hv2 = NAT_HASH_FN6(&nat->nat_oip6, hv2 + nat->nat_oport, ifs->ifs_ipf_nattable_sz); } else { hv1 = NAT_HASH_FN6(&nat->nat_inip6, 0, 0xffffffff); hv1 = NAT_HASH_FN6(&nat->nat_oip6, hv1, ifs->ifs_ipf_nattable_sz); hv2 = NAT_HASH_FN6(&nat->nat_outip6, 0, 0xffffffff); hv2 = NAT_HASH_FN6(&nat->nat_oip6, hv2, ifs->ifs_ipf_nattable_sz); } if ((ifs->ifs_nat_stats.ns_bucketlen[0][hv1] >= ifs->ifs_fr_nat_maxbucket) || (ifs->ifs_nat_stats.ns_bucketlen[1][hv2] >= ifs->ifs_fr_nat_maxbucket)) { return -1; } nat->nat_hv[0] = hv1; nat->nat_hv[1] = hv2; MUTEX_INIT(&nat->nat_lock, "nat entry lock"); nat->nat_rev = rev; nat->nat_ref = 1; nat->nat_bytes[0] = 0; nat->nat_pkts[0] = 0; nat->nat_bytes[1] = 0; nat->nat_pkts[1] = 0; nat->nat_ifnames[0][LIFNAMSIZ - 1] = '\0'; nat->nat_ifps[0] = fr_resolvenic(nat->nat_ifnames[0], 6, ifs); if (nat->nat_ifnames[1][0] !='\0') { nat->nat_ifnames[1][LIFNAMSIZ - 1] = '\0'; nat->nat_ifps[1] = fr_resolvenic(nat->nat_ifnames[1], 6, ifs); } else { (void) strncpy(nat->nat_ifnames[1], nat->nat_ifnames[0], LIFNAMSIZ); nat->nat_ifnames[1][LIFNAMSIZ - 1] = '\0'; nat->nat_ifps[1] = nat->nat_ifps[0]; } nat->nat_next = ifs->ifs_nat_instances; nat->nat_pnext = &ifs->ifs_nat_instances; if (ifs->ifs_nat_instances) ifs->ifs_nat_instances->nat_pnext = &nat->nat_next; ifs->ifs_nat_instances = nat; natp = &ifs->ifs_nat_table[0][hv1]; if (*natp) (*natp)->nat_phnext[0] = &nat->nat_hnext[0]; nat->nat_phnext[0] = natp; nat->nat_hnext[0] = *natp; *natp = nat; ifs->ifs_nat_stats.ns_bucketlen[0][hv1]++; natp = &ifs->ifs_nat_table[1][hv2]; if (*natp) (*natp)->nat_phnext[1] = &nat->nat_hnext[1]; nat->nat_phnext[1] = natp; nat->nat_hnext[1] = *natp; *natp = nat; ifs->ifs_nat_stats.ns_bucketlen[1][hv2]++; fr_setnatqueue(nat, rev, ifs); ifs->ifs_nat_stats.ns_added++; ifs->ifs_nat_stats.ns_inuse++; return 0; } /* ------------------------------------------------------------------------ */ /* Function: nat6_icmperrorlookup */ /* Returns: nat_t* - point to matching NAT structure */ /* Parameters: fin(I) - pointer to packet information */ /* dir(I) - direction of packet (in/out) */ /* */ /* Check if the ICMP error message is related to an existing TCP, UDP or */ /* ICMP query nat entry. It is assumed that the packet is already of the */ /* the required length. */ /* ------------------------------------------------------------------------ */ nat_t *nat6_icmperrorlookup(fin, dir) fr_info_t *fin; int dir; { int flags = 0, minlen; struct icmp6_hdr *orgicmp; tcphdr_t *tcp = NULL; u_short data[2]; nat_t *nat; ip6_t *oip6; u_int p; minlen = 40; /* * Does it at least have the return (basic) IP header ? * Only a basic IP header (no options) should be with an ICMP error * header. Also, if it's not an error type, then return. */ if (!(fin->fin_flx & FI_ICMPERR)) return NULL; /* * Check packet size */ if (fin->fin_plen < ICMP6ERR_IPICMPHLEN) return NULL; oip6 = (ip6_t *)((char *)fin->fin_dp + 8); /* * Is the buffer big enough for all of it ? It's the size of the IP * header claimed in the encapsulated part which is of concern. It * may be too big to be in this buffer but not so big that it's * outside the ICMP packet, leading to TCP deref's causing problems. * This is possible because we don't know how big oip_hl is when we * do the pullup early in fr_check() and thus can't gaurantee it is * all here now. */ #ifdef _KERNEL { mb_t *m; m = fin->fin_m; # if defined(MENTAT) if ((char *)oip6 + fin->fin_dlen - ICMPERR_ICMPHLEN > (char *)m->b_wptr) return NULL; # else if ((char *)oip6 + fin->fin_dlen - ICMPERR_ICMPHLEN > (char *)fin->fin_ip + M_LEN(m)) return NULL; # endif } #endif if (IP6_NEQ(&fin->fin_dst6, &oip6->ip6_src)) return NULL; p = oip6->ip6_nxt; if (p == IPPROTO_TCP) flags = IPN_TCP; else if (p == IPPROTO_UDP) flags = IPN_UDP; else if (p == IPPROTO_ICMPV6) { orgicmp = (struct icmp6_hdr *)(oip6 + 1); /* see if this is related to an ICMP query */ if (nat_icmpquerytype6(orgicmp->icmp6_type)) { data[0] = fin->fin_data[0]; data[1] = fin->fin_data[1]; fin->fin_data[0] = 0; fin->fin_data[1] = orgicmp->icmp6_id; flags = IPN_ICMPERR|IPN_ICMPQUERY; /* * NOTE : dir refers to the direction of the original * ip packet. By definition the icmp error * message flows in the opposite direction. */ if (dir == NAT_INBOUND) nat = nat6_inlookup(fin, flags, p, &oip6->ip6_dst, &oip6->ip6_src); else nat = nat6_outlookup(fin, flags, p, &oip6->ip6_dst, &oip6->ip6_src); fin->fin_data[0] = data[0]; fin->fin_data[1] = data[1]; return nat; } } if (flags & IPN_TCPUDP) { minlen += 8; /* + 64bits of data to get ports */ if (fin->fin_plen < ICMPERR_ICMPHLEN + minlen) return NULL; data[0] = fin->fin_data[0]; data[1] = fin->fin_data[1]; tcp = (tcphdr_t *)(oip6 + 1); fin->fin_data[0] = ntohs(tcp->th_dport); fin->fin_data[1] = ntohs(tcp->th_sport); if (dir == NAT_INBOUND) { nat = nat6_inlookup(fin, flags, p, &oip6->ip6_dst, &oip6->ip6_src); } else { nat = nat6_outlookup(fin, flags, p, &oip6->ip6_dst, &oip6->ip6_src); } fin->fin_data[0] = data[0]; fin->fin_data[1] = data[1]; return nat; } if (dir == NAT_INBOUND) return nat6_inlookup(fin, 0, p, &oip6->ip6_dst, &oip6->ip6_src); else return nat6_outlookup(fin, 0, p, &oip6->ip6_dst, &oip6->ip6_src); } /* ------------------------------------------------------------------------ */ /* Function: nat6_icmperror */ /* Returns: nat_t* - point to matching NAT structure */ /* Parameters: fin(I) - pointer to packet information */ /* nflags(I) - NAT flags for this packet */ /* dir(I) - direction of packet (in/out) */ /* */ /* Fix up an ICMP packet which is an error message for an existing NAT */ /* session. This will correct both packet header data and checksums. */ /* */ /* This should *ONLY* be used for incoming ICMP error packets to make sure */ /* a NAT'd ICMP packet gets correctly recognised. */ /* ------------------------------------------------------------------------ */ nat_t *nat6_icmperror(fin, nflags, dir) fr_info_t *fin; u_int *nflags; int dir; { u_32_t sum1, sum2, sumd, psum1, psum2, psumd, sumd1; i6addr_t in; struct icmp6_hdr *icmp6, *orgicmp; int dlen; udphdr_t *udp; tcphdr_t *tcp; nat_t *nat; ip6_t *oip6; if ((fin->fin_flx & (FI_SHORT|FI_FRAGBODY))) return NULL; /* * nat6_icmperrorlookup() looks up nat entry associated with the * offending IP packet and returns pointer to the entry, or NULL * if packet wasn't natted or for `defective' packets. */ if ((fin->fin_v != 6) || !(nat = nat6_icmperrorlookup(fin, dir))) return NULL; sumd1 = 0; *nflags = IPN_ICMPERR; icmp6 = fin->fin_dp; oip6 = (ip6_t *)((char *)icmp6 + sizeof (*icmp6)); udp = (udphdr_t *)(((char *)oip6) + sizeof (*oip6)); tcp = (tcphdr_t *)udp; dlen = fin->fin_plen - ((char *)udp - (char *)fin->fin_ip); /* * Need to adjust ICMP header to include the real IP#'s and * port #'s. There are three steps required. * * Step 1 * No update needed for ip6 header checksum. * * Unlike IPv4, we need to update icmp_cksum for IPv6 address * changes because there's no ip_sum change to cancel it. */ if (IP6_EQ((i6addr_t *)&oip6->ip6_dst, &nat->nat_oip6)) { sum1 = LONG_SUM6((i6addr_t *)&oip6->ip6_src); in = nat->nat_inip6; oip6->ip6_src = in.in6; } else { sum1 = LONG_SUM6((i6addr_t *)&oip6->ip6_dst); in = nat->nat_outip6; oip6->ip6_dst = in.in6; } sum2 = LONG_SUM6(&in); CALC_SUMD(sum1, sum2, sumd); /* * Step 2 * Perform other adjustments based on protocol of offending packet. */ switch (oip6->ip6_nxt) { case IPPROTO_TCP : case IPPROTO_UDP : /* * For offending TCP/UDP IP packets, translate the ports * based on the NAT specification. * * Advance notice : Now it becomes complicated :-) * * Since the port and IP addresse fields are both part * of the TCP/UDP checksum of the offending IP packet, * we need to adjust that checksum as well. * * To further complicate things, the TCP/UDP checksum * may not be present. We must check to see if the * length of the data portion is big enough to hold * the checksum. In the UDP case, a test to determine * if the checksum is even set is also required. * * Any changes to an IP address, port or checksum within * the ICMP packet requires a change to icmp_cksum. * * Be extremely careful here ... The change is dependent * upon whether or not the TCP/UPD checksum is present. * * If TCP/UPD checksum is present, the icmp_cksum must * compensate for checksum modification resulting from * IP address change only. Port change and resulting * data checksum adjustments cancel each other out. * * If TCP/UDP checksum is not present, icmp_cksum must * compensate for port change only. The IP address * change does not modify anything else in this case. */ psum1 = 0; psum2 = 0; psumd = 0; if ((tcp->th_dport == nat->nat_oport) && (tcp->th_sport != nat->nat_inport)) { /* * Translate the source port. */ psum1 = ntohs(tcp->th_sport); psum2 = ntohs(nat->nat_inport); tcp->th_sport = nat->nat_inport; } else if ((tcp->th_sport == nat->nat_oport) && (tcp->th_dport != nat->nat_outport)) { /* * Translate the destination port. */ psum1 = ntohs(tcp->th_dport); psum2 = ntohs(nat->nat_outport); tcp->th_dport = nat->nat_outport; } if ((oip6->ip6_nxt == IPPROTO_TCP) && (dlen >= 18)) { /* * TCP checksum present. * * Adjust data checksum and icmp checksum to * compensate for any IP address change. */ sum1 = ntohs(tcp->th_sum); fix_datacksum(&tcp->th_sum, sumd); sum2 = ntohs(tcp->th_sum); CALC_SUMD(sum1, sum2, sumd); sumd1 += sumd; /* * Also make data checksum adjustment to * compensate for any port change. */ if (psum1 != psum2) { CALC_SUMD(psum1, psum2, psumd); fix_datacksum(&tcp->th_sum, psumd); } } else if ((oip6->ip6_nxt == IPPROTO_UDP) && (dlen >= 8) && (udp->uh_sum != 0)) { /* * The UDP checksum is present and set. * * Adjust data checksum and icmp checksum to * compensate for any IP address change. */ sum1 = ntohs(udp->uh_sum); fix_datacksum(&udp->uh_sum, sumd); sum2 = ntohs(udp->uh_sum); CALC_SUMD(sum1, sum2, sumd); sumd1 += sumd; /* * Also make data checksum adjustment to * compensate for any port change. */ if (psum1 != psum2) { CALC_SUMD(psum1, psum2, psumd); fix_datacksum(&udp->uh_sum, psumd); } } else { /* * Data checksum was not present. * * Compensate for any port change. */ CALC_SUMD(psum2, psum1, psumd); sumd1 += psumd; } break; case IPPROTO_ICMPV6 : orgicmp = (struct icmp6_hdr *)udp; if ((nat->nat_dir == NAT_OUTBOUND) && (orgicmp->icmp6_id != nat->nat_inport) && (dlen >= 8)) { /* * Fix ICMP checksum (of the offening ICMP * query packet) to compensate the change * in the ICMP id of the offending ICMP * packet. * * Since you modify orgicmp->icmp_id with * a delta (say x) and you compensate that * in origicmp->icmp_cksum with a delta * minus x, you don't have to adjust the * overall icmp->icmp_cksum */ sum1 = ntohs(orgicmp->icmp6_id); sum2 = ntohs(nat->nat_inport); CALC_SUMD(sum1, sum2, sumd); orgicmp->icmp6_id = nat->nat_inport; fix_datacksum(&orgicmp->icmp6_cksum, sumd); } /* nat_dir can't be NAT_INBOUND for icmp queries */ break; default : break; } /* switch (oip6->ip6_nxt) */ /* * Step 3 * Make the adjustments to icmp checksum. */ if (sumd1 != 0) { sumd1 = (sumd1 & 0xffff) + (sumd1 >> 16); sumd1 = (sumd1 & 0xffff) + (sumd1 >> 16); fix_incksum(&icmp6->icmp6_cksum, sumd1); } return nat; } /* * NB: these lookups don't lock access to the list, it assumed that it has * already been done! */ /* ------------------------------------------------------------------------ */ /* Function: nat6_inlookup */ /* Returns: nat_t* - NULL == no match, */ /* else pointer to matching NAT entry */ /* Parameters: fin(I) - pointer to packet information */ /* flags(I) - NAT flags for this packet */ /* p(I) - protocol for this packet */ /* src(I) - source IP address */ /* mapdst(I) - destination IP address */ /* */ /* Lookup a nat entry based on the mapped destination ip address/port and */ /* real source address/port. We use this lookup when receiving a packet, */ /* we're looking for a table entry, based on the destination address. */ /* */ /* NOTE: THE PACKET BEING CHECKED (IF FOUND) HAS A MAPPING ALREADY. */ /* */ /* NOTE: IT IS ASSUMED THAT ipf_nat IS ONLY HELD WITH A READ LOCK WHEN */ /* THIS FUNCTION IS CALLED WITH NAT_SEARCH SET IN nflags. */ /* */ /* flags -> relevant are IPN_UDP/IPN_TCP/IPN_ICMPQUERY that indicate if */ /* the packet is of said protocol */ /* ------------------------------------------------------------------------ */ nat_t *nat6_inlookup(fin, flags, p, src, mapdst) fr_info_t *fin; u_int flags, p; struct in6_addr *src, *mapdst; { u_short sport, dport; u_int sflags; nat_t *nat; int nflags; i6addr_t dst; void *ifp; u_int hv; ipf_stack_t *ifs = fin->fin_ifs; if (fin != NULL) ifp = fin->fin_ifp; else ifp = NULL; sport = 0; dport = 0; dst.in6 = *mapdst; sflags = flags & NAT_TCPUDPICMP; switch (p) { case IPPROTO_TCP : case IPPROTO_UDP : sport = htons(fin->fin_data[0]); dport = htons(fin->fin_data[1]); break; case IPPROTO_ICMPV6 : if (flags & IPN_ICMPERR) sport = fin->fin_data[1]; else dport = fin->fin_data[1]; break; default : break; } if ((flags & SI_WILDP) != 0) goto find_in_wild_ports; hv = NAT_HASH_FN6(&dst, dport, 0xffffffff); hv = NAT_HASH_FN6(src, hv + sport, ifs->ifs_ipf_nattable_sz); nat = ifs->ifs_nat_table[1][hv]; for (; nat; nat = nat->nat_hnext[1]) { if (nat->nat_v != 6) continue; if (nat->nat_ifps[0] != NULL) { if ((ifp != NULL) && (ifp != nat->nat_ifps[0])) continue; } else if (ifp != NULL) nat->nat_ifps[0] = ifp; nflags = nat->nat_flags; if (IP6_EQ(&nat->nat_oip6, src) && IP6_EQ(&nat->nat_outip6, &dst) && (((p == 0) && (sflags == (nat->nat_flags & IPN_TCPUDPICMP))) || (p == nat->nat_p))) { switch (p) { #if 0 case IPPROTO_GRE : if (nat->nat_call[1] != fin->fin_data[0]) continue; break; #endif case IPPROTO_ICMPV6 : if ((flags & IPN_ICMPERR) != 0) { if (nat->nat_outport != sport) continue; } else { if (nat->nat_outport != dport) continue; } break; case IPPROTO_TCP : case IPPROTO_UDP : if (nat->nat_oport != sport) continue; if (nat->nat_outport != dport) continue; break; default : break; } #ifdef IPF_V6_PROXIES ipn = nat->nat_ptr; if ((ipn != NULL) && (nat->nat_aps != NULL)) if (appr_match(fin, nat) != 0) continue; #endif return nat; } } /* * So if we didn't find it but there are wildcard members in the hash * table, go back and look for them. We do this search and update here * because it is modifying the NAT table and we want to do this only * for the first packet that matches. The exception, of course, is * for "dummy" (FI_IGNORE) lookups. */ find_in_wild_ports: if (!(flags & NAT_TCPUDP) || !(flags & NAT_SEARCH)) return NULL; if (ifs->ifs_nat_stats.ns_wilds == 0) return NULL; RWLOCK_EXIT(&ifs->ifs_ipf_nat); hv = NAT_HASH_FN6(&dst, 0, 0xffffffff); hv = NAT_HASH_FN6(src, hv, ifs->ifs_ipf_nattable_sz); WRITE_ENTER(&ifs->ifs_ipf_nat); nat = ifs->ifs_nat_table[1][hv]; for (; nat; nat = nat->nat_hnext[1]) { if (nat->nat_v != 6) continue; if (nat->nat_ifps[0] != NULL) { if ((ifp != NULL) && (ifp != nat->nat_ifps[0])) continue; } else if (ifp != NULL) nat->nat_ifps[0] = ifp; if (nat->nat_p != fin->fin_p) continue; if (IP6_NEQ(&nat->nat_oip6, src) || IP6_NEQ(&nat->nat_outip6, &dst)) continue; nflags = nat->nat_flags; if (!(nflags & (NAT_TCPUDP|SI_WILDP))) continue; if (nat_wildok(nat, (int)sport, (int)dport, nflags, NAT_INBOUND) == 1) { if ((fin->fin_flx & FI_IGNORE) != 0) break; if ((nflags & SI_CLONE) != 0) { nat = fr_natclone(fin, nat); if (nat == NULL) break; } else { MUTEX_ENTER(&ifs->ifs_ipf_nat_new); ifs->ifs_nat_stats.ns_wilds--; MUTEX_EXIT(&ifs->ifs_ipf_nat_new); } nat->nat_oport = sport; nat->nat_outport = dport; nat->nat_flags &= ~(SI_W_DPORT|SI_W_SPORT); nat6_tabmove(nat, ifs); break; } } MUTEX_DOWNGRADE(&ifs->ifs_ipf_nat); return nat; } /* ------------------------------------------------------------------------ */ /* Function: nat6_tabmove */ /* Returns: Nil */ /* Parameters: nat(I) - pointer to NAT structure */ /* Write Lock: ipf_nat */ /* */ /* This function is only called for TCP/UDP NAT table entries where the */ /* original was placed in the table without hashing on the ports and we now */ /* want to include hashing on port numbers. */ /* ------------------------------------------------------------------------ */ static void nat6_tabmove(nat, ifs) nat_t *nat; ipf_stack_t *ifs; { nat_t **natp; u_int hv; if (nat->nat_flags & SI_CLONE) return; /* * Remove the NAT entry from the old location */ if (nat->nat_hnext[0]) nat->nat_hnext[0]->nat_phnext[0] = nat->nat_phnext[0]; *nat->nat_phnext[0] = nat->nat_hnext[0]; ifs->ifs_nat_stats.ns_bucketlen[0][nat->nat_hv[0]]--; if (nat->nat_hnext[1]) nat->nat_hnext[1]->nat_phnext[1] = nat->nat_phnext[1]; *nat->nat_phnext[1] = nat->nat_hnext[1]; ifs->ifs_nat_stats.ns_bucketlen[1][nat->nat_hv[1]]--; /* * Add into the NAT table in the new position */ hv = NAT_HASH_FN6(&nat->nat_inip6, nat->nat_inport, 0xffffffff); hv = NAT_HASH_FN6(&nat->nat_oip6, hv + nat->nat_oport, ifs->ifs_ipf_nattable_sz); nat->nat_hv[0] = hv; natp = &ifs->ifs_nat_table[0][hv]; if (*natp) (*natp)->nat_phnext[0] = &nat->nat_hnext[0]; nat->nat_phnext[0] = natp; nat->nat_hnext[0] = *natp; *natp = nat; ifs->ifs_nat_stats.ns_bucketlen[0][hv]++; hv = NAT_HASH_FN6(&nat->nat_outip6, nat->nat_outport, 0xffffffff); hv = NAT_HASH_FN6(&nat->nat_oip6, hv + nat->nat_oport, ifs->ifs_ipf_nattable_sz); nat->nat_hv[1] = hv; natp = &ifs->ifs_nat_table[1][hv]; if (*natp) (*natp)->nat_phnext[1] = &nat->nat_hnext[1]; nat->nat_phnext[1] = natp; nat->nat_hnext[1] = *natp; *natp = nat; ifs->ifs_nat_stats.ns_bucketlen[1][hv]++; } /* ------------------------------------------------------------------------ */ /* Function: nat6_outlookup */ /* Returns: nat_t* - NULL == no match, */ /* else pointer to matching NAT entry */ /* Parameters: fin(I) - pointer to packet information */ /* flags(I) - NAT flags for this packet */ /* p(I) - protocol for this packet */ /* src(I) - source IP address */ /* dst(I) - destination IP address */ /* rw(I) - 1 == write lock on ipf_nat held, 0 == read lock. */ /* */ /* Lookup a nat entry based on the source 'real' ip address/port and */ /* destination address/port. We use this lookup when sending a packet out, */ /* we're looking for a table entry, based on the source address. */ /* */ /* NOTE: THE PACKET BEING CHECKED (IF FOUND) HAS A MAPPING ALREADY. */ /* */ /* NOTE: IT IS ASSUMED THAT ipf_nat IS ONLY HELD WITH A READ LOCK WHEN */ /* THIS FUNCTION IS CALLED WITH NAT_SEARCH SET IN nflags. */ /* */ /* flags -> relevant are IPN_UDP/IPN_TCP/IPN_ICMPQUERY that indicate if */ /* the packet is of said protocol */ /* ------------------------------------------------------------------------ */ nat_t *nat6_outlookup(fin, flags, p, src, dst) fr_info_t *fin; u_int flags, p; struct in6_addr *src , *dst; { u_short sport, dport; u_int sflags; nat_t *nat; int nflags; void *ifp; u_int hv; ipf_stack_t *ifs = fin->fin_ifs; ifp = fin->fin_ifp; sflags = flags & IPN_TCPUDPICMP; sport = 0; dport = 0; switch (p) { case IPPROTO_TCP : case IPPROTO_UDP : sport = htons(fin->fin_data[0]); dport = htons(fin->fin_data[1]); break; case IPPROTO_ICMPV6 : if (flags & IPN_ICMPERR) sport = fin->fin_data[1]; else dport = fin->fin_data[1]; break; default : break; } if ((flags & SI_WILDP) != 0) goto find_out_wild_ports; hv = NAT_HASH_FN6(src, sport, 0xffffffff); hv = NAT_HASH_FN6(dst, hv + dport, ifs->ifs_ipf_nattable_sz); nat = ifs->ifs_nat_table[0][hv]; for (; nat; nat = nat->nat_hnext[0]) { if (nat->nat_v != 6) continue; if (nat->nat_ifps[1] != NULL) { if ((ifp != NULL) && (ifp != nat->nat_ifps[1])) continue; } else if (ifp != NULL) nat->nat_ifps[1] = ifp; nflags = nat->nat_flags; if (IP6_EQ(&nat->nat_inip6, src) && IP6_EQ(&nat->nat_oip6, dst) && (((p == 0) && (sflags == (nflags & NAT_TCPUDPICMP))) || (p == nat->nat_p))) { switch (p) { #if 0 case IPPROTO_GRE : if (nat->nat_call[1] != fin->fin_data[0]) continue; break; #endif case IPPROTO_TCP : case IPPROTO_UDP : if (nat->nat_oport != dport) continue; if (nat->nat_inport != sport) continue; break; default : break; } #ifdef IPF_V6_PROXIES ipn = nat->nat_ptr; if ((ipn != NULL) && (nat->nat_aps != NULL)) if (appr_match(fin, nat) != 0) continue; #endif return nat; } } /* * So if we didn't find it but there are wildcard members in the hash * table, go back and look for them. We do this search and update here * because it is modifying the NAT table and we want to do this only * for the first packet that matches. The exception, of course, is * for "dummy" (FI_IGNORE) lookups. */ find_out_wild_ports: if (!(flags & NAT_TCPUDP) || !(flags & NAT_SEARCH)) return NULL; if (ifs->ifs_nat_stats.ns_wilds == 0) return NULL; RWLOCK_EXIT(&ifs->ifs_ipf_nat); hv = NAT_HASH_FN6(src, 0, 0xffffffff); hv = NAT_HASH_FN6(dst, hv, ifs->ifs_ipf_nattable_sz); WRITE_ENTER(&ifs->ifs_ipf_nat); nat = ifs->ifs_nat_table[0][hv]; for (; nat; nat = nat->nat_hnext[0]) { if (nat->nat_v != 6) continue; if (nat->nat_ifps[1] != NULL) { if ((ifp != NULL) && (ifp != nat->nat_ifps[1])) continue; } else if (ifp != NULL) nat->nat_ifps[1] = ifp; if (nat->nat_p != fin->fin_p) continue; if (IP6_NEQ(&nat->nat_inip6, src) || IP6_NEQ(&nat->nat_oip6, dst)) continue; nflags = nat->nat_flags; if (!(nflags & (NAT_TCPUDP|SI_WILDP))) continue; if (nat_wildok(nat, (int)sport, (int)dport, nflags, NAT_OUTBOUND) == 1) { if ((fin->fin_flx & FI_IGNORE) != 0) break; if ((nflags & SI_CLONE) != 0) { nat = fr_natclone(fin, nat); if (nat == NULL) break; } else { MUTEX_ENTER(&ifs->ifs_ipf_nat_new); ifs->ifs_nat_stats.ns_wilds--; MUTEX_EXIT(&ifs->ifs_ipf_nat_new); } nat->nat_inport = sport; nat->nat_oport = dport; if (nat->nat_outport == 0) nat->nat_outport = sport; nat->nat_flags &= ~(SI_W_DPORT|SI_W_SPORT); nat6_tabmove(nat, ifs); break; } } MUTEX_DOWNGRADE(&ifs->ifs_ipf_nat); return nat; } /* ------------------------------------------------------------------------ */ /* Function: nat6_lookupredir */ /* Returns: nat_t* - NULL == no match, */ /* else pointer to matching NAT entry */ /* Parameters: np(I) - pointer to description of packet to find NAT table */ /* entry for. */ /* */ /* Lookup the NAT tables to search for a matching redirect */ /* ------------------------------------------------------------------------ */ nat_t *nat6_lookupredir(np, ifs) natlookup_t *np; ipf_stack_t *ifs; { fr_info_t fi; nat_t *nat; bzero((char *)&fi, sizeof (fi)); if (np->nl_flags & IPN_IN) { fi.fin_data[0] = ntohs(np->nl_realport); fi.fin_data[1] = ntohs(np->nl_outport); } else { fi.fin_data[0] = ntohs(np->nl_inport); fi.fin_data[1] = ntohs(np->nl_outport); } if (np->nl_flags & IPN_TCP) fi.fin_p = IPPROTO_TCP; else if (np->nl_flags & IPN_UDP) fi.fin_p = IPPROTO_UDP; else if (np->nl_flags & (IPN_ICMPERR|IPN_ICMPQUERY)) fi.fin_p = IPPROTO_ICMPV6; fi.fin_ifs = ifs; /* * We can do two sorts of lookups: * - IPN_IN: we have the `real' and `out' address, look for `in'. * - default: we have the `in' and `out' address, look for `real'. */ if (np->nl_flags & IPN_IN) { if ((nat = nat6_inlookup(&fi, np->nl_flags, fi.fin_p, &np->nl_realip6, &np->nl_outip6))) { np->nl_inipaddr = nat->nat_inip6; np->nl_inport = nat->nat_inport; } } else { /* * If nl_inip is non null, this is a lookup based on the real * ip address. Else, we use the fake. */ if ((nat = nat6_outlookup(&fi, np->nl_flags, fi.fin_p, &np->nl_inip6, &np->nl_outip6))) { if ((np->nl_flags & IPN_FINDFORWARD) != 0) { fr_info_t fin; bzero((char *)&fin, sizeof (fin)); fin.fin_p = nat->nat_p; fin.fin_data[0] = ntohs(nat->nat_outport); fin.fin_data[1] = ntohs(nat->nat_oport); fin.fin_ifs = ifs; if (nat6_inlookup(&fin, np->nl_flags, fin.fin_p, &nat->nat_outip6.in6, &nat->nat_oip6.in6) != NULL) { np->nl_flags &= ~IPN_FINDFORWARD; } } np->nl_realip6 = nat->nat_outip6.in6; np->nl_realport = nat->nat_outport; } } return nat; } /* ------------------------------------------------------------------------ */ /* Function: nat6_match */ /* Returns: int - 0 == no match, 1 == match */ /* Parameters: fin(I) - pointer to packet information */ /* np(I) - pointer to NAT rule */ /* */ /* Pull the matching of a packet against a NAT rule out of that complex */ /* loop inside fr_checknat6in() and lay it out properly in its own function.*/ /* ------------------------------------------------------------------------ */ static int nat6_match(fin, np) fr_info_t *fin; ipnat_t *np; { frtuc_t *ft; if (fin->fin_v != 6) return 0; if (np->in_p && fin->fin_p != np->in_p) return 0; if (fin->fin_out) { if (!(np->in_redir & (NAT_MAP|NAT_MAPBLK))) return 0; if (IP6_MASKNEQ(&fin->fin_src6, &np->in_in[1], &np->in_in[0]) ^ ((np->in_flags & IPN_NOTSRC) != 0)) return 0; if (IP6_MASKNEQ(&fin->fin_dst6, &np->in_src[1], &np->in_src[0]) ^ ((np->in_flags & IPN_NOTDST) != 0)) return 0; } else { if (!(np->in_redir & NAT_REDIRECT)) return 0; if (IP6_MASKNEQ(&fin->fin_src6, &np->in_src[1], &np->in_src[0]) ^ ((np->in_flags & IPN_NOTSRC) != 0)) return 0; if (IP6_MASKNEQ(&fin->fin_dst6, &np->in_out[1], &np->in_out[0]) ^ ((np->in_flags & IPN_NOTDST) != 0)) return 0; } ft = &np->in_tuc; if (!(fin->fin_flx & FI_TCPUDP) || (fin->fin_flx & (FI_SHORT|FI_FRAGBODY))) { if (ft->ftu_scmp || ft->ftu_dcmp) return 0; return 1; } return fr_tcpudpchk(fin, ft); } /* ------------------------------------------------------------------------ */ /* Function: fr_checknat6out */ /* Returns: int - -1 == packet failed NAT checks so block it, */ /* 0 == no packet translation occurred, */ /* 1 == packet was successfully translated. */ /* Parameters: fin(I) - pointer to packet information */ /* passp(I) - pointer to filtering result flags */ /* */ /* Check to see if an outcoming packet should be changed. ICMP packets are */ /* first checked to see if they match an existing entry (if an error), */ /* otherwise a search of the current NAT table is made. If neither results */ /* in a match then a search for a matching NAT rule is made. Create a new */ /* NAT entry if a we matched a NAT rule. Lastly, actually change the */ /* packet header(s) as required. */ /* ------------------------------------------------------------------------ */ int fr_checknat6out(fin, passp) fr_info_t *fin; u_32_t *passp; { struct ifnet *ifp, *sifp; int rval, natfailed; ipnat_t *np = NULL; u_int nflags = 0; i6addr_t ipa, iph; int natadd = 1; frentry_t *fr; nat_t *nat; ipf_stack_t *ifs = fin->fin_ifs; if (ifs->ifs_nat_stats.ns_rules == 0 || ifs->ifs_fr_nat_lock != 0) return 0; natfailed = 0; fr = fin->fin_fr; sifp = fin->fin_ifp; if ((fr != NULL) && !(fr->fr_flags & FR_DUP) && fr->fr_tifs[fin->fin_rev].fd_ifp && fr->fr_tifs[fin->fin_rev].fd_ifp != (void *)-1) fin->fin_ifp = fr->fr_tifs[fin->fin_rev].fd_ifp; ifp = fin->fin_ifp; if (!(fin->fin_flx & FI_SHORT) && (fin->fin_off == 0)) { switch (fin->fin_p) { case IPPROTO_TCP : nflags = IPN_TCP; break; case IPPROTO_UDP : nflags = IPN_UDP; break; case IPPROTO_ICMPV6 : /* * This is an incoming packet, so the destination is * the icmp6_id and the source port equals 0 */ if ((fin->fin_flx & FI_ICMPQUERY) != 0) nflags = IPN_ICMPQUERY; break; default : break; } #ifdef IPF_V6_PROXIES if ((nflags & IPN_TCPUDP)) tcp = fin->fin_dp; #endif } ipa = fin->fin_src6; READ_ENTER(&ifs->ifs_ipf_nat); if ((fin->fin_p == IPPROTO_ICMPV6) && !(nflags & IPN_ICMPQUERY) && (nat = nat6_icmperror(fin, &nflags, NAT_OUTBOUND))) /*EMPTY*/; else if ((fin->fin_flx & FI_FRAG) && (nat = fr_nat_knownfrag(fin))) natadd = 0; else if ((nat = nat6_outlookup(fin, nflags|NAT_SEARCH, (u_int)fin->fin_p, &fin->fin_src6.in6, &fin->fin_dst6.in6))) { nflags = nat->nat_flags; } else { u_32_t hv, nmsk; i6addr_t msk; int i; /* * If there is no current entry in the nat table for this IP#, * create one for it (if there is a matching rule). */ RWLOCK_EXIT(&ifs->ifs_ipf_nat); i = 3; msk.i6[0] = 0xffffffff; msk.i6[1] = 0xffffffff; msk.i6[2] = 0xffffffff; msk.i6[3] = 0xffffffff; nmsk = ifs->ifs_nat6_masks[3]; WRITE_ENTER(&ifs->ifs_ipf_nat); maskloop: IP6_AND(&ipa, &msk, &iph); hv = NAT_HASH_FN6(&iph, 0, ifs->ifs_ipf_natrules_sz); for (np = ifs->ifs_nat_rules[hv]; np; np = np->in_mnext) { if ((np->in_ifps[1] && (np->in_ifps[1] != ifp))) continue; if (np->in_v != 6) continue; if (np->in_p && (np->in_p != fin->fin_p)) continue; if ((np->in_flags & IPN_RF) && !(np->in_flags & nflags)) continue; if (np->in_flags & IPN_FILTER) { if (!nat6_match(fin, np)) continue; } else if (!IP6_MASKEQ(&ipa, &np->in_in[1], &np->in_in[0])) continue; if ((fr != NULL) && !fr_matchtag(&np->in_tag, &fr->fr_nattag)) continue; #ifdef IPF_V6_PROXIES if (*np->in_plabel != '\0') { if (((np->in_flags & IPN_FILTER) == 0) && (np->in_dport != tcp->th_dport)) continue; if (appr_ok(fin, tcp, np) == 0) continue; } #endif if (nat = nat6_new(fin, np, NULL, nflags, NAT_OUTBOUND)) { np->in_hits++; break; } else natfailed = -1; } if ((np == NULL) && (i >= 0)) { while (i >= 0) { while (nmsk) { msk.i6[i] = htonl(ntohl(msk.i6[i])<<1); if ((nmsk & 0x80000000) != 0) { nmsk <<= 1; goto maskloop; } nmsk <<= 1; } msk.i6[i--] = 0; if (i >= 0) { nmsk = ifs->ifs_nat6_masks[i]; if (nmsk != 0) goto maskloop; } } } MUTEX_DOWNGRADE(&ifs->ifs_ipf_nat); } if (nat != NULL) { rval = fr_nat6out(fin, nat, natadd, nflags); if (rval == 1) { MUTEX_ENTER(&nat->nat_lock); nat->nat_ref++; MUTEX_EXIT(&nat->nat_lock); nat->nat_touched = ifs->ifs_fr_ticks; fin->fin_nat = nat; } } else rval = natfailed; RWLOCK_EXIT(&ifs->ifs_ipf_nat); if (rval == -1) { if (passp != NULL) *passp = FR_BLOCK; fin->fin_flx |= FI_BADNAT; } fin->fin_ifp = sifp; return rval; } /* ------------------------------------------------------------------------ */ /* Function: fr_nat6out */ /* Returns: int - -1 == packet failed NAT checks so block it, */ /* 1 == packet was successfully translated. */ /* Parameters: fin(I) - pointer to packet information */ /* nat(I) - pointer to NAT structure */ /* natadd(I) - flag indicating if it is safe to add frag cache */ /* nflags(I) - NAT flags set for this packet */ /* */ /* Translate a packet coming "out" on an interface. */ /* ------------------------------------------------------------------------ */ int fr_nat6out(fin, nat, natadd, nflags) fr_info_t *fin; nat_t *nat; int natadd; u_32_t nflags; { struct icmp6_hdr *icmp6; u_short *csump; tcphdr_t *tcp; ipnat_t *np; int i; ipf_stack_t *ifs = fin->fin_ifs; #if SOLARIS && defined(_KERNEL) net_data_t net_data_p = ifs->ifs_ipf_ipv6; #endif tcp = NULL; icmp6 = NULL; csump = NULL; np = nat->nat_ptr; if ((natadd != 0) && (fin->fin_flx & FI_FRAG)) (void) fr_nat_newfrag(fin, 0, nat); MUTEX_ENTER(&nat->nat_lock); nat->nat_bytes[1] += fin->fin_plen; nat->nat_pkts[1]++; MUTEX_EXIT(&nat->nat_lock); if (!(fin->fin_flx & FI_SHORT) && (fin->fin_off == 0)) { if ((nat->nat_outport != 0) && (nflags & IPN_TCPUDP)) { tcp = fin->fin_dp; tcp->th_sport = nat->nat_outport; fin->fin_data[0] = ntohs(nat->nat_outport); } if ((nat->nat_outport != 0) && (nflags & IPN_ICMPQUERY)) { icmp6 = fin->fin_dp; icmp6->icmp6_id = nat->nat_outport; } csump = nat_proto(fin, nat, nflags); } fin->fin_ip6->ip6_src = nat->nat_outip6.in6; fin->fin_src6 = nat->nat_outip6; nat_update(fin, nat, np); /* * TCP/UDP/ICMPv6 checksum needs to be adjusted. */ if (csump != NULL && (!(nflags & IPN_TCPUDP) || !NET_IS_HCK_L4_FULL(net_data_p, fin->fin_m))) { if (nflags & IPN_TCPUDP && NET_IS_HCK_L4_PART(net_data_p, fin->fin_m)) { if (nat->nat_dir == NAT_OUTBOUND) fix_outcksum(csump, nat->nat_sumd[1]); else fix_incksum(csump, nat->nat_sumd[1]); } else { if (nat->nat_dir == NAT_OUTBOUND) fix_outcksum(csump, nat->nat_sumd[0]); else fix_incksum(csump, nat->nat_sumd[0]); } } #ifdef IPFILTER_SYNC ipfsync_update(SMC_NAT, fin, nat->nat_sync); #endif /* ------------------------------------------------------------- */ /* A few quick notes: */ /* Following are test conditions prior to calling the */ /* appr_check routine. */ /* */ /* A NULL tcp indicates a non TCP/UDP packet. When dealing */ /* with a redirect rule, we attempt to match the packet's */ /* source port against in_dport, otherwise we'd compare the */ /* packet's destination. */ /* ------------------------------------------------------------- */ if ((np != NULL) && (np->in_apr != NULL)) { i = appr_check(fin, nat); if (i == 0) i = 1; } else i = 1; ATOMIC_INCL(ifs->ifs_nat_stats.ns_mapped[1]); fin->fin_flx |= FI_NATED; return i; } /* ------------------------------------------------------------------------ */ /* Function: fr_checknat6in */ /* Returns: int - -1 == packet failed NAT checks so block it, */ /* 0 == no packet translation occurred, */ /* 1 == packet was successfully translated. */ /* Parameters: fin(I) - pointer to packet information */ /* passp(I) - pointer to filtering result flags */ /* */ /* Check to see if an incoming packet should be changed. ICMP packets are */ /* first checked to see if they match an existing entry (if an error), */ /* otherwise a search of the current NAT table is made. If neither results */ /* in a match then a search for a matching NAT rule is made. Create a new */ /* NAT entry if a we matched a NAT rule. Lastly, actually change the */ /* packet header(s) as required. */ /* ------------------------------------------------------------------------ */ int fr_checknat6in(fin, passp) fr_info_t *fin; u_32_t *passp; { u_int nflags, natadd; int rval, natfailed; struct ifnet *ifp; struct icmp6_hdr *icmp6; tcphdr_t *tcp; u_short dport; ipnat_t *np; nat_t *nat; i6addr_t ipa, iph; ipf_stack_t *ifs = fin->fin_ifs; if (ifs->ifs_nat_stats.ns_rules == 0 || ifs->ifs_fr_nat_lock != 0) return 0; tcp = NULL; icmp6 = NULL; dport = 0; natadd = 1; nflags = 0; natfailed = 0; ifp = fin->fin_ifp; if (!(fin->fin_flx & FI_SHORT) && (fin->fin_off == 0)) { switch (fin->fin_p) { case IPPROTO_TCP : nflags = IPN_TCP; break; case IPPROTO_UDP : nflags = IPN_UDP; break; case IPPROTO_ICMPV6 : icmp6 = fin->fin_dp; /* * This is an incoming packet, so the destination is * the icmp_id and the source port equals 0 */ if ((fin->fin_flx & FI_ICMPQUERY) != 0) { nflags = IPN_ICMPQUERY; dport = icmp6->icmp6_id; } break; default : break; } if ((nflags & IPN_TCPUDP)) { tcp = fin->fin_dp; dport = tcp->th_dport; } } ipa = fin->fin_dst6; READ_ENTER(&ifs->ifs_ipf_nat); if ((fin->fin_p == IPPROTO_ICMPV6) && !(nflags & IPN_ICMPQUERY) && (nat = nat6_icmperror(fin, &nflags, NAT_INBOUND))) /*EMPTY*/; else if ((fin->fin_flx & FI_FRAG) && (nat = fr_nat_knownfrag(fin))) natadd = 0; else if ((nat = nat6_inlookup(fin, nflags|NAT_SEARCH, (u_int)fin->fin_p, &fin->fin_src6.in6, &ipa.in6))) { nflags = nat->nat_flags; } else { u_32_t hv, rmsk; i6addr_t msk; int i; RWLOCK_EXIT(&ifs->ifs_ipf_nat); i = 3; msk.i6[0] = 0xffffffff; msk.i6[1] = 0xffffffff; msk.i6[2] = 0xffffffff; msk.i6[3] = 0xffffffff; rmsk = ifs->ifs_rdr6_masks[3]; WRITE_ENTER(&ifs->ifs_ipf_nat); /* * If there is no current entry in the nat table for this IP#, * create one for it (if there is a matching rule). */ maskloop: IP6_AND(&ipa, &msk, &iph); hv = NAT_HASH_FN6(&iph, 0, ifs->ifs_ipf_rdrrules_sz); for (np = ifs->ifs_rdr_rules[hv]; np; np = np->in_rnext) { if (np->in_ifps[0] && (np->in_ifps[0] != ifp)) continue; if (np->in_v != fin->fin_v) continue; if (np->in_p && (np->in_p != fin->fin_p)) continue; if ((np->in_flags & IPN_RF) && !(np->in_flags & nflags)) continue; if (np->in_flags & IPN_FILTER) { if (!nat6_match(fin, np)) continue; } else { if (!IP6_MASKEQ(&ipa, &np->in_out[1], &np->in_out[0])) continue; if (np->in_pmin && ((ntohs(np->in_pmax) < ntohs(dport)) || (ntohs(dport) < ntohs(np->in_pmin)))) continue; } #ifdef IPF_V6_PROXIES if (*np->in_plabel != '\0') { if (!appr_ok(fin, tcp, np)) { continue; } } #endif nat = nat6_new(fin, np, NULL, nflags, NAT_INBOUND); if (nat != NULL) { np->in_hits++; break; } else natfailed = -1; } if ((np == NULL) && (i >= 0)) { while (i >= 0) { while (rmsk) { msk.i6[i] = htonl(ntohl(msk.i6[i])<<1); if ((rmsk & 0x80000000) != 0) { rmsk <<= 1; goto maskloop; } rmsk <<= 1; } msk.i6[i--] = 0; if (i >= 0) { rmsk = ifs->ifs_rdr6_masks[i]; if (rmsk != 0) goto maskloop; } } } MUTEX_DOWNGRADE(&ifs->ifs_ipf_nat); } if (nat != NULL) { rval = fr_nat6in(fin, nat, natadd, nflags); if (rval == 1) { MUTEX_ENTER(&nat->nat_lock); nat->nat_ref++; MUTEX_EXIT(&nat->nat_lock); nat->nat_touched = ifs->ifs_fr_ticks; fin->fin_nat = nat; fin->fin_state = nat->nat_state; } } else rval = natfailed; RWLOCK_EXIT(&ifs->ifs_ipf_nat); if (rval == -1) { if (passp != NULL) *passp = FR_BLOCK; fin->fin_flx |= FI_BADNAT; } return rval; } /* ------------------------------------------------------------------------ */ /* Function: fr_nat6in */ /* Returns: int - -1 == packet failed NAT checks so block it, */ /* 1 == packet was successfully translated. */ /* Parameters: fin(I) - pointer to packet information */ /* nat(I) - pointer to NAT structure */ /* natadd(I) - flag indicating if it is safe to add frag cache */ /* nflags(I) - NAT flags set for this packet */ /* Locks Held: ipf_nat (READ) */ /* */ /* Translate a packet coming "in" on an interface. */ /* ------------------------------------------------------------------------ */ int fr_nat6in(fin, nat, natadd, nflags) fr_info_t *fin; nat_t *nat; int natadd; u_32_t nflags; { struct icmp6_hdr *icmp6; u_short *csump; tcphdr_t *tcp; ipnat_t *np; ipf_stack_t *ifs = fin->fin_ifs; #if SOLARIS && defined(_KERNEL) net_data_t net_data_p = ifs->ifs_ipf_ipv6; #endif tcp = NULL; csump = NULL; np = nat->nat_ptr; fin->fin_fr = nat->nat_fr; if ((natadd != 0) && (fin->fin_flx & FI_FRAG)) (void) fr_nat_newfrag(fin, 0, nat); #ifdef IPF_V6_PROXIES if (np != NULL) { /* ------------------------------------------------------------- */ /* A few quick notes: */ /* Following are test conditions prior to calling the */ /* appr_check routine. */ /* */ /* A NULL tcp indicates a non TCP/UDP packet. When dealing */ /* with a map rule, we attempt to match the packet's */ /* source port against in_dport, otherwise we'd compare the */ /* packet's destination. */ /* ------------------------------------------------------------- */ if (np->in_apr != NULL) { i = appr_check(fin, nat); if (i == -1) { return -1; } } } #endif #ifdef IPFILTER_SYNC ipfsync_update(SMC_NAT, fin, nat->nat_sync); #endif MUTEX_ENTER(&nat->nat_lock); nat->nat_bytes[0] += fin->fin_plen; nat->nat_pkts[0]++; MUTEX_EXIT(&nat->nat_lock); fin->fin_ip6->ip6_dst = nat->nat_inip6.in6; fin->fin_dst6 = nat->nat_inip6; if (nflags & IPN_TCPUDP) tcp = fin->fin_dp; if (!(fin->fin_flx & FI_SHORT) && (fin->fin_off == 0)) { if ((nat->nat_inport != 0) && (nflags & IPN_TCPUDP)) { tcp->th_dport = nat->nat_inport; fin->fin_data[1] = ntohs(nat->nat_inport); } if ((nat->nat_inport != 0) && (nflags & IPN_ICMPQUERY)) { icmp6 = fin->fin_dp; icmp6->icmp6_id = nat->nat_inport; } csump = nat_proto(fin, nat, nflags); } nat_update(fin, nat, np); /* * In case they are being forwarded, inbound packets always need to have * their checksum adjusted even if hardware checksum validation said OK. */ if (csump != NULL) { if (nat->nat_dir == NAT_OUTBOUND) fix_incksum(csump, nat->nat_sumd[0]); else fix_outcksum(csump, nat->nat_sumd[0]); } #if SOLARIS && defined(_KERNEL) if (nflags & IPN_TCPUDP && NET_IS_HCK_L4_PART(net_data_p, fin->fin_m)) { /* * Need to adjust the partial checksum result stored in * db_cksum16, which will be used for validation in IP. * See IP_CKSUM_RECV(). * Adjustment data should be the inverse of the IP address * changes, because db_cksum16 is supposed to be the complement * of the pesudo header. */ csump = &fin->fin_m->b_datap->db_cksum16; if (nat->nat_dir == NAT_OUTBOUND) fix_outcksum(csump, nat->nat_sumd[1]); else fix_incksum(csump, nat->nat_sumd[1]); } #endif ATOMIC_INCL(ifs->ifs_nat_stats.ns_mapped[0]); fin->fin_flx |= FI_NATED; if (np != NULL && np->in_tag.ipt_num[0] != 0) fin->fin_nattag = &np->in_tag; return 1; } /* ------------------------------------------------------------------------ */ /* Function: nat_icmpquerytype6 */ /* Returns: int - 1 == success, 0 == failure */ /* Parameters: icmptype(I) - ICMP type number */ /* */ /* Tests to see if the ICMP type number passed is a query/response type or */ /* not. */ /* ------------------------------------------------------------------------ */ static INLINE int nat_icmpquerytype6(icmptype) int icmptype; { /* * For the ICMP query NAT code, it is essential that both the query * and the reply match on the NAT rule. Because the NAT structure * does not keep track of the icmptype, and a single NAT structure * is used for all icmp types with the same src, dest and id, we * simply define the replies as queries as well. The funny thing is, * altough it seems silly to call a reply a query, this is exactly * as it is defined in the IPv4 specification */ switch (icmptype) { case ICMP6_ECHO_REPLY: case ICMP6_ECHO_REQUEST: /* route aedvertisement/solliciation is currently unsupported: */ /* it would require rewriting the ICMP data section */ case ICMP6_MEMBERSHIP_QUERY: case ICMP6_MEMBERSHIP_REPORT: case ICMP6_MEMBERSHIP_REDUCTION: case ICMP6_WRUREQUEST: case ICMP6_WRUREPLY: case MLD6_MTRACE_RESP: case MLD6_MTRACE: return 1; default: return 0; } }