Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   1) // SPDX-License-Identifier: GPL-2.0-or-later
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   3)  * Stateless NAT actions
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   4)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   5)  * Copyright (c) 2007 Herbert Xu <herbert@gondor.apana.org.au>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   6)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   7) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   8) #include <linux/errno.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   9) #include <linux/init.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  10) #include <linux/kernel.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  11) #include <linux/module.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  12) #include <linux/netfilter.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  13) #include <linux/rtnetlink.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  14) #include <linux/skbuff.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  15) #include <linux/slab.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  16) #include <linux/spinlock.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  17) #include <linux/string.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  18) #include <linux/tc_act/tc_nat.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  19) #include <net/act_api.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  20) #include <net/pkt_cls.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  21) #include <net/icmp.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  22) #include <net/ip.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  23) #include <net/netlink.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  24) #include <net/tc_act/tc_nat.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  25) #include <net/tcp.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  26) #include <net/udp.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  27) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  28) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  29) static unsigned int nat_net_id;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  30) static struct tc_action_ops act_nat_ops;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  31) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  32) static const struct nla_policy nat_policy[TCA_NAT_MAX + 1] = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  33) 	[TCA_NAT_PARMS]	= { .len = sizeof(struct tc_nat) },
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  34) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  35) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  36) static int tcf_nat_init(struct net *net, struct nlattr *nla, struct nlattr *est,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  37) 			struct tc_action **a, int ovr, int bind,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  38) 			bool rtnl_held,	struct tcf_proto *tp,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  39) 			u32 flags, struct netlink_ext_ack *extack)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  40) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  41) 	struct tc_action_net *tn = net_generic(net, nat_net_id);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  42) 	struct nlattr *tb[TCA_NAT_MAX + 1];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  43) 	struct tcf_chain *goto_ch = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  44) 	struct tc_nat *parm;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  45) 	int ret = 0, err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  46) 	struct tcf_nat *p;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  47) 	u32 index;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  48) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  49) 	if (nla == NULL)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  50) 		return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  51) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  52) 	err = nla_parse_nested_deprecated(tb, TCA_NAT_MAX, nla, nat_policy,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  53) 					  NULL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  54) 	if (err < 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  55) 		return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  56) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  57) 	if (tb[TCA_NAT_PARMS] == NULL)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  58) 		return -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  59) 	parm = nla_data(tb[TCA_NAT_PARMS]);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  60) 	index = parm->index;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  61) 	err = tcf_idr_check_alloc(tn, &index, a, bind);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  62) 	if (!err) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  63) 		ret = tcf_idr_create(tn, index, est, a,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  64) 				     &act_nat_ops, bind, false, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  65) 		if (ret) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  66) 			tcf_idr_cleanup(tn, index);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  67) 			return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  68) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  69) 		ret = ACT_P_CREATED;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  70) 	} else if (err > 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  71) 		if (bind)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  72) 			return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  73) 		if (!ovr) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  74) 			tcf_idr_release(*a, bind);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  75) 			return -EEXIST;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  76) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  77) 	} else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  78) 		return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  79) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  80) 	err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  81) 	if (err < 0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  82) 		goto release_idr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  83) 	p = to_tcf_nat(*a);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  84) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  85) 	spin_lock_bh(&p->tcf_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  86) 	p->old_addr = parm->old_addr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  87) 	p->new_addr = parm->new_addr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  88) 	p->mask = parm->mask;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  89) 	p->flags = parm->flags;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  90) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  91) 	goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  92) 	spin_unlock_bh(&p->tcf_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  93) 	if (goto_ch)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  94) 		tcf_chain_put_by_act(goto_ch);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  95) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  96) 	return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  97) release_idr:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  98) 	tcf_idr_release(*a, bind);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  99) 	return err;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) static int tcf_nat_act(struct sk_buff *skb, const struct tc_action *a,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) 		       struct tcf_result *res)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) 	struct tcf_nat *p = to_tcf_nat(a);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) 	struct iphdr *iph;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) 	__be32 old_addr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) 	__be32 new_addr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) 	__be32 mask;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) 	__be32 addr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) 	int egress;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) 	int action;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) 	int ihl;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) 	int noff;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) 	spin_lock(&p->tcf_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) 	tcf_lastuse_update(&p->tcf_tm);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) 	old_addr = p->old_addr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) 	new_addr = p->new_addr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) 	mask = p->mask;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) 	egress = p->flags & TCA_NAT_FLAG_EGRESS;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) 	action = p->tcf_action;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) 	bstats_update(&p->tcf_bstats, skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) 	spin_unlock(&p->tcf_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) 	if (unlikely(action == TC_ACT_SHOT))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130) 		goto drop;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) 	noff = skb_network_offset(skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) 	if (!pskb_may_pull(skb, sizeof(*iph) + noff))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) 		goto drop;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) 	iph = ip_hdr(skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) 	if (egress)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) 		addr = iph->saddr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) 	else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) 		addr = iph->daddr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) 	if (!((old_addr ^ addr) & mask)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) 		if (skb_try_make_writable(skb, sizeof(*iph) + noff))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) 			goto drop;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) 		new_addr &= mask;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) 		new_addr |= addr & ~mask;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) 		/* Rewrite IP header */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) 		iph = ip_hdr(skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) 		if (egress)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) 			iph->saddr = new_addr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) 		else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) 			iph->daddr = new_addr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) 		csum_replace4(&iph->check, addr, new_addr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) 	} else if ((iph->frag_off & htons(IP_OFFSET)) ||
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) 		   iph->protocol != IPPROTO_ICMP) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) 		goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163) 	ihl = iph->ihl * 4;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165) 	/* It would be nice to share code with stateful NAT. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166) 	switch (iph->frag_off & htons(IP_OFFSET) ? 0 : iph->protocol) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167) 	case IPPROTO_TCP:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168) 	{
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169) 		struct tcphdr *tcph;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171) 		if (!pskb_may_pull(skb, ihl + sizeof(*tcph) + noff) ||
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) 		    skb_try_make_writable(skb, ihl + sizeof(*tcph) + noff))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173) 			goto drop;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175) 		tcph = (void *)(skb_network_header(skb) + ihl);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176) 		inet_proto_csum_replace4(&tcph->check, skb, addr, new_addr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) 					 true);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) 		break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180) 	case IPPROTO_UDP:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) 	{
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182) 		struct udphdr *udph;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184) 		if (!pskb_may_pull(skb, ihl + sizeof(*udph) + noff) ||
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185) 		    skb_try_make_writable(skb, ihl + sizeof(*udph) + noff))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186) 			goto drop;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 188) 		udph = (void *)(skb_network_header(skb) + ihl);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 189) 		if (udph->check || skb->ip_summed == CHECKSUM_PARTIAL) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190) 			inet_proto_csum_replace4(&udph->check, skb, addr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191) 						 new_addr, true);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192) 			if (!udph->check)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 193) 				udph->check = CSUM_MANGLED_0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 194) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 195) 		break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 196) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 197) 	case IPPROTO_ICMP:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 198) 	{
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 199) 		struct icmphdr *icmph;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 200) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 201) 		if (!pskb_may_pull(skb, ihl + sizeof(*icmph) + noff))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 202) 			goto drop;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 203) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 204) 		icmph = (void *)(skb_network_header(skb) + ihl);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 205) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 206) 		if (!icmp_is_err(icmph->type))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 207) 			break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 208) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 209) 		if (!pskb_may_pull(skb, ihl + sizeof(*icmph) + sizeof(*iph) +
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 210) 					noff))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 211) 			goto drop;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 212) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 213) 		icmph = (void *)(skb_network_header(skb) + ihl);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 214) 		iph = (void *)(icmph + 1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 215) 		if (egress)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 216) 			addr = iph->daddr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 217) 		else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 218) 			addr = iph->saddr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 219) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 220) 		if ((old_addr ^ addr) & mask)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 221) 			break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 222) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 223) 		if (skb_try_make_writable(skb, ihl + sizeof(*icmph) +
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 224) 					  sizeof(*iph) + noff))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 225) 			goto drop;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 226) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 227) 		icmph = (void *)(skb_network_header(skb) + ihl);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 228) 		iph = (void *)(icmph + 1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 229) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 230) 		new_addr &= mask;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 231) 		new_addr |= addr & ~mask;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 232) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 233) 		/* XXX Fix up the inner checksums. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 234) 		if (egress)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 235) 			iph->daddr = new_addr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 236) 		else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 237) 			iph->saddr = new_addr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 238) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 239) 		inet_proto_csum_replace4(&icmph->checksum, skb, addr, new_addr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 240) 					 false);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 241) 		break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 242) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 243) 	default:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 244) 		break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 245) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 246) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 247) out:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 248) 	return action;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 249) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 250) drop:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 251) 	spin_lock(&p->tcf_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 252) 	p->tcf_qstats.drops++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 253) 	spin_unlock(&p->tcf_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 254) 	return TC_ACT_SHOT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 255) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 256) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 257) static int tcf_nat_dump(struct sk_buff *skb, struct tc_action *a,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 258) 			int bind, int ref)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 259) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 260) 	unsigned char *b = skb_tail_pointer(skb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 261) 	struct tcf_nat *p = to_tcf_nat(a);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 262) 	struct tc_nat opt = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 263) 		.index    = p->tcf_index,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 264) 		.refcnt   = refcount_read(&p->tcf_refcnt) - ref,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 265) 		.bindcnt  = atomic_read(&p->tcf_bindcnt) - bind,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 266) 	};
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 267) 	struct tcf_t t;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 268) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 269) 	spin_lock_bh(&p->tcf_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 270) 	opt.old_addr = p->old_addr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 271) 	opt.new_addr = p->new_addr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 272) 	opt.mask = p->mask;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 273) 	opt.flags = p->flags;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 274) 	opt.action = p->tcf_action;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 275) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 276) 	if (nla_put(skb, TCA_NAT_PARMS, sizeof(opt), &opt))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 277) 		goto nla_put_failure;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 278) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 279) 	tcf_tm_dump(&t, &p->tcf_tm);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 280) 	if (nla_put_64bit(skb, TCA_NAT_TM, sizeof(t), &t, TCA_NAT_PAD))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 281) 		goto nla_put_failure;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 282) 	spin_unlock_bh(&p->tcf_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 283) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 284) 	return skb->len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 285) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 286) nla_put_failure:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 287) 	spin_unlock_bh(&p->tcf_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 288) 	nlmsg_trim(skb, b);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 289) 	return -1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 290) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 291) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 292) static int tcf_nat_walker(struct net *net, struct sk_buff *skb,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 293) 			  struct netlink_callback *cb, int type,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 294) 			  const struct tc_action_ops *ops,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 295) 			  struct netlink_ext_ack *extack)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 296) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 297) 	struct tc_action_net *tn = net_generic(net, nat_net_id);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 298) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 299) 	return tcf_generic_walker(tn, skb, cb, type, ops, extack);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 300) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 301) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 302) static int tcf_nat_search(struct net *net, struct tc_action **a, u32 index)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 303) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 304) 	struct tc_action_net *tn = net_generic(net, nat_net_id);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 305) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 306) 	return tcf_idr_search(tn, a, index);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 307) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 308) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 309) static struct tc_action_ops act_nat_ops = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 310) 	.kind		=	"nat",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 311) 	.id		=	TCA_ID_NAT,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 312) 	.owner		=	THIS_MODULE,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 313) 	.act		=	tcf_nat_act,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 314) 	.dump		=	tcf_nat_dump,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 315) 	.init		=	tcf_nat_init,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 316) 	.walk		=	tcf_nat_walker,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 317) 	.lookup		=	tcf_nat_search,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 318) 	.size		=	sizeof(struct tcf_nat),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 319) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 320) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 321) static __net_init int nat_init_net(struct net *net)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 322) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 323) 	struct tc_action_net *tn = net_generic(net, nat_net_id);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 324) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 325) 	return tc_action_net_init(net, tn, &act_nat_ops);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 326) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 327) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 328) static void __net_exit nat_exit_net(struct list_head *net_list)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 329) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 330) 	tc_action_net_exit(net_list, nat_net_id);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 331) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 332) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 333) static struct pernet_operations nat_net_ops = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 334) 	.init = nat_init_net,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 335) 	.exit_batch = nat_exit_net,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 336) 	.id   = &nat_net_id,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 337) 	.size = sizeof(struct tc_action_net),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 338) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 339) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 340) MODULE_DESCRIPTION("Stateless NAT actions");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 341) MODULE_LICENSE("GPL");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 342) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 343) static int __init nat_init_module(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 344) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 345) 	return tcf_register_action(&act_nat_ops, &nat_net_ops);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 346) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 347) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 348) static void __exit nat_cleanup_module(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 349) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 350) 	tcf_unregister_action(&act_nat_ops, &nat_net_ops);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 351) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 352) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 353) module_init(nat_init_module);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 354) module_exit(nat_cleanup_module);