Differential D19561 Diff 54983 sys/netpfil/ipfw/nat64/nat64clat.c

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sys/netpfil/ipfw/nat64/nat64clat.c

This file was copied from sys/netpfil/ipfw/nat64/nat64stl.c.

/*-		/*-
* Copyright (c) 2015-2016 Yandex LLC		* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
* Copyright (c) 2015-2016 Andrey V. Elsukov <ae@FreeBSD.org>
* All rights reserved.
*		*
		* Copyright (c) 2019 Yandex LLC
		* Copyright (c) 2019 Andrey V. Elsukov <ae@FreeBSD.org>
		* Copyright (c) 2019 Boris N. Lytochkin <lytboris@gmail.com>
		*
* Redistribution and use in source and binary forms, with or without		* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions		* modification, are permitted provided that the following conditions
* are met:		* are met:
*		*
* 1. Redistributions of source code must retain the above copyright		* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.		* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright		* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the		* notice, this list of conditions and the following disclaimer in the
Show All 38 Lines
#include <netinet/ip_fw.h>		#include <netinet/ip_fw.h>
#include <netinet/ip6.h>		#include <netinet/ip6.h>
#include <netinet/icmp6.h>		#include <netinet/icmp6.h>
#include <netinet6/ip_fw_nat64.h>		#include <netinet6/ip_fw_nat64.h>

#include <netpfil/ipfw/ip_fw_private.h>		#include <netpfil/ipfw/ip_fw_private.h>
#include <netpfil/pf/pf.h>		#include <netpfil/pf/pf.h>

#include "nat64stl.h"		#include "nat64clat.h"

#define NAT64_LOOKUP(chain, cmd) \		#define NAT64_LOOKUP(chain, cmd) \
(struct nat64stl_cfg *)SRV_OBJECT((chain), (cmd)->arg1)		(struct nat64clat_cfg *)SRV_OBJECT((chain), (cmd)->arg1)

static void		static void
nat64stl_log(struct pfloghdr plog, struct mbuf m, sa_family_t family,		nat64clat_log(struct pfloghdr plog, struct mbuf m, sa_family_t family,
uint32_t kidx)		uint32_t kidx)
{		{
static uint32_t pktid = 0;		static uint32_t pktid = 0;

memset(plog, 0, sizeof(*plog));		memset(plog, 0, sizeof(*plog));
plog->length = PFLOG_REAL_HDRLEN;		plog->length = PFLOG_REAL_HDRLEN;
plog->af = family;		plog->af = family;
plog->action = PF_NAT;		plog->action = PF_NAT;
plog->dir = PF_IN;		plog->dir = PF_IN;
plog->rulenr = htonl(kidx);		plog->rulenr = htonl(kidx);
pktid++;		pktid++;
plog->subrulenr = htonl(pktid);		plog->subrulenr = htonl(pktid);
plog->ruleset[0] = '\0';		plog->ruleset[0] = '\0';
strlcpy(plog->ifname, "NAT64STL", sizeof(plog->ifname));		strlcpy(plog->ifname, "NAT64CLAT", sizeof(plog->ifname));
ipfw_bpf_mtap2(plog, PFLOG_HDRLEN, m);		ipfw_bpf_mtap2(plog, PFLOG_HDRLEN, m);
}		}

static int		static int
nat64stl_handle_ip4(struct ip_fw_chain chain, struct nat64stl_cfg cfg,		nat64clat_handle_ip4(struct ip_fw_chain chain, struct nat64clat_cfg cfg,
struct mbuf *m, uint32_t tablearg)		struct mbuf *m)
{		{
struct pfloghdr loghdr, *logdata;		struct pfloghdr loghdr, *logdata;
struct in6_addr saddr, daddr;		struct in6_addr saddr, daddr;
struct ip *ip;		struct ip *ip;

ip = mtod(m, struct ip*);		ip = mtod(m, struct ip*);
		/* source address for CLAT may be private with no harm */
if (nat64_check_ip4(ip->ip_src.s_addr) != 0 \|\|		if (nat64_check_ip4(ip->ip_src.s_addr) != 0 \|\|
nat64_check_ip4(ip->ip_dst.s_addr) != 0 \|\|		nat64_check_ip4(ip->ip_dst.s_addr) != 0 \|\|
nat64_check_private_ip4(&cfg->base, ip->ip_src.s_addr) != 0 \|\|
nat64_check_private_ip4(&cfg->base, ip->ip_dst.s_addr) != 0)		nat64_check_private_ip4(&cfg->base, ip->ip_dst.s_addr) != 0)
return (NAT64SKIP);		return (NAT64SKIP);

daddr = TARG_VAL(chain, tablearg, nh6);		memcpy(&saddr, &cfg->base.clat_prefix, sizeof(saddr));
if (nat64_check_ip6(&daddr) != 0)		nat64_embed_ip4(&saddr, cfg->base.clat_plen, ip->ip_src.s_addr);
return (NAT64MFREE);		memcpy(&daddr, &cfg->base.plat_prefix, sizeof(daddr));
nat64_embed_ip4(&cfg->base, ip->ip_src.s_addr, &saddr);		nat64_embed_ip4(&daddr, cfg->base.plat_plen, ip->ip_dst.s_addr);
if (cfg->base.flags & NAT64_LOG) {		if (cfg->base.flags & NAT64_LOG) {
logdata = &loghdr;		logdata = &loghdr;
nat64stl_log(logdata, m, AF_INET, cfg->no.kidx);		nat64clat_log(logdata, m, AF_INET, cfg->no.kidx);
} else		} else
logdata = NULL;		logdata = NULL;
return (nat64_do_handle_ip4(m, &saddr, &daddr, 0, &cfg->base,		return (nat64_do_handle_ip4(m, &saddr, &daddr, 0, &cfg->base,
logdata));		logdata));
}		}

static int		static int
nat64stl_handle_ip6(struct ip_fw_chain chain, struct nat64stl_cfg cfg,		nat64clat_handle_ip6(struct ip_fw_chain chain, struct nat64clat_cfg cfg,
struct mbuf *m, uint32_t tablearg)		struct mbuf *m)
{		{
struct pfloghdr loghdr, *logdata;		struct pfloghdr loghdr, *logdata;
struct ip6_hdr *ip6;		struct ip6_hdr *ip6;
uint32_t aaddr;		uint32_t aaddr;

aaddr = htonl(TARG_VAL(chain, tablearg, nh4));

/*		/*
* NOTE: we expect ipfw_chk() did m_pullup() up to upper level		* NOTE: we expect ipfw_chk() did m_pullup() up to upper level
* protocol's headers. Also we skip some checks, that ip6_input(),		* protocol's headers. Also we skip some checks, that ip6_input(),
* ip6_forward(), ip6_fastfwd() and ipfw_chk() already did.		* ip6_forward(), ip6_fastfwd() and ipfw_chk() already did.
*/		*/
ip6 = mtod(m, struct ip6_hdr *);		ip6 = mtod(m, struct ip6_hdr *);
/* Check ip6_dst matches configured prefix */		/* Check ip6_dst matches configured prefix */
if (bcmp(&ip6->ip6_dst, &cfg->base.prefix6, cfg->base.plen6 / 8) != 0)		if (memcmp(&ip6->ip6_dst, &cfg->base.clat_prefix,
		cfg->base.clat_plen / 8) != 0)
return (NAT64SKIP);		return (NAT64SKIP);
		/* Check ip6_src matches configured prefix */
		if (memcmp(&ip6->ip6_src, &cfg->base.plat_prefix,
		cfg->base.plat_plen / 8) != 0)
		return (NAT64SKIP);

if (cfg->base.flags & NAT64_LOG) {		if (cfg->base.flags & NAT64_LOG) {
logdata = &loghdr;		logdata = &loghdr;
nat64stl_log(logdata, m, AF_INET6, cfg->no.kidx);		nat64clat_log(logdata, m, AF_INET6, cfg->no.kidx);
} else		} else
logdata = NULL;		logdata = NULL;

		aaddr = nat64_extract_ip4(&ip6->ip6_src, cfg->base.plat_plen);
return (nat64_do_handle_ip6(m, aaddr, 0, &cfg->base, logdata));		return (nat64_do_handle_ip6(m, aaddr, 0, &cfg->base, logdata));
}		}

static int		static int
nat64stl_handle_icmp6(struct ip_fw_chain chain, struct nat64stl_cfg cfg,		nat64clat_handle_icmp6(struct ip_fw_chain chain, struct nat64clat_cfg cfg,
struct mbuf *m)		struct mbuf *m)
{		{
struct pfloghdr loghdr, *logdata;		struct pfloghdr loghdr, *logdata;
struct nat64_counters *stats;		struct nat64_counters *stats;
struct ip6_hdr *ip6i;		struct ip6_hdr *ip6i;
struct icmp6_hdr *icmp6;		struct icmp6_hdr *icmp6;
uint32_t tablearg;		uint32_t daddr;
int hlen, proto;		int hlen, proto;

hlen = 0;		hlen = 0;
stats = &cfg->base.stats;		stats = &cfg->base.stats;
proto = nat64_getlasthdr(m, &hlen);		proto = nat64_getlasthdr(m, &hlen);
if (proto != IPPROTO_ICMPV6) {		if (proto != IPPROTO_ICMPV6) {
NAT64STAT_INC(stats, dropped);		NAT64STAT_INC(stats, dropped);
return (NAT64MFREE);		return (NAT64MFREE);
Show All 20 Lines	if (m == NULL) {
NAT64STAT_INC(stats, nomem);		NAT64STAT_INC(stats, nomem);
return (NAT64RETURN);		return (NAT64RETURN);
}		}
/*		/*
* Use destination address from inner IPv6 header to determine		* Use destination address from inner IPv6 header to determine
* IPv4 mapped address.		* IPv4 mapped address.
*/		*/
ip6i = mtodo(m, hlen);		ip6i = mtodo(m, hlen);
if (ipfw_lookup_table(chain, cfg->map64,		daddr = nat64_extract_ip4(&ip6i->ip6_dst, cfg->base.clat_plen);
sizeof(struct in6_addr), &ip6i->ip6_dst, &tablearg) == 0) {		if (daddr == 0) {
m_freem(m);		NAT64STAT_INC(stats, dropped);
return (NAT64RETURN);		return (NAT64MFREE);
}		}
if (cfg->base.flags & NAT64_LOG) {		if (cfg->base.flags & NAT64_LOG) {
logdata = &loghdr;		logdata = &loghdr;
nat64stl_log(logdata, m, AF_INET6, cfg->no.kidx);		nat64clat_log(logdata, m, AF_INET6, cfg->no.kidx);
} else		} else
logdata = NULL;		logdata = NULL;
return (nat64_handle_icmp6(m, 0,		return (nat64_handle_icmp6(m, 0, daddr, 0, &cfg->base, logdata));
htonl(TARG_VAL(chain, tablearg, nh4)), 0, &cfg->base, logdata));
}		}

int		int
ipfw_nat64stl(struct ip_fw_chain chain, struct ip_fw_args args,		ipfw_nat64clat(struct ip_fw_chain chain, struct ip_fw_args args,
ipfw_insn cmd, int done)		ipfw_insn cmd, int done)
{		{
ipfw_insn *icmd;		ipfw_insn *icmd;
struct nat64stl_cfg *cfg;		struct nat64clat_cfg *cfg;
in_addr_t dst4;
uint32_t tablearg;
int ret;		int ret;

IPFW_RLOCK_ASSERT(chain);		IPFW_RLOCK_ASSERT(chain);

done = 0; / try next rule if not matched */		done = 0; / try next rule if not matched */
icmd = cmd + 1;		icmd = cmd + 1;
if (cmd->opcode != O_EXTERNAL_ACTION \|\|		if (cmd->opcode != O_EXTERNAL_ACTION \|\|
cmd->arg1 != V_nat64stl_eid \|\|		cmd->arg1 != V_nat64clat_eid \|\|
icmd->opcode != O_EXTERNAL_INSTANCE \|\|		icmd->opcode != O_EXTERNAL_INSTANCE \|\|
(cfg = NAT64_LOOKUP(chain, icmd)) == NULL)		(cfg = NAT64_LOOKUP(chain, icmd)) == NULL)
return (0);		return (0);

switch (args->f_id.addr_type) {		switch (args->f_id.addr_type) {
case 4:		case 4:
dst4 = htonl(args->f_id.dst_ip);		ret = nat64clat_handle_ip4(chain, cfg, args->m);
ret = ipfw_lookup_table(chain, cfg->map46, sizeof(in_addr_t),
&dst4, &tablearg);
break;		break;
case 6:		case 6:
ret = ipfw_lookup_table(chain, cfg->map64,		ret = nat64clat_handle_ip6(chain, cfg, args->m);
sizeof(struct in6_addr), &args->f_id.src_ip6, &tablearg);
break;		break;
default:		default:
return (0);		return (0);
}		}
if (ret == 0) {
		if (ret == NAT64SKIP) {
/*		/*
* In case when packet is ICMPv6 message from an intermediate		* In case when packet is ICMPv6 message from an intermediate
* router, the source address of message will not match the		* router, the source address of message will not match the
* addresses from our map64 table.		* addresses from configured prefixes.
*/		*/
if (args->f_id.proto != IPPROTO_ICMPV6)		if (args->f_id.proto != IPPROTO_ICMPV6)
return (0);		return (0);

ret = nat64stl_handle_icmp6(chain, cfg, args->m);		ret = nat64clat_handle_icmp6(chain, cfg, args->m);
} else {
if (args->f_id.addr_type == 4)
ret = nat64stl_handle_ip4(chain, cfg, args->m,
tablearg);
else
ret = nat64stl_handle_ip6(chain, cfg, args->m,
tablearg);
}		}

if (ret == NAT64SKIP)		if (ret == NAT64SKIP)
return (0);		return (0);

done = 1; / terminate the search */		done = 1; / terminate the search */
if (ret == NAT64MFREE)		if (ret == NAT64MFREE)
m_freem(args->m);		m_freem(args->m);

args->m = NULL;		args->m = NULL;
return (IP_FW_DENY);		return (IP_FW_NAT64);
}		}