1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/export.h>
3 #include <linux/icmpv6.h>
4 #include <linux/mutex.h>
5 #include <linux/netdevice.h>
6 #include <linux/spinlock.h>
7
8 #include <net/ipv6.h>
9
10 #if IS_ENABLED(CONFIG_IPV6)
11
12 #if !IS_BUILTIN(CONFIG_IPV6)
13
14 static ip6_icmp_send_t __rcu *ip6_icmp_send;
15
inet6_register_icmp_sender(ip6_icmp_send_t * fn)16 int inet6_register_icmp_sender(ip6_icmp_send_t *fn)
17 {
18 return (cmpxchg((ip6_icmp_send_t **)&ip6_icmp_send, NULL, fn) == NULL) ?
19 0 : -EBUSY;
20 }
21 EXPORT_SYMBOL(inet6_register_icmp_sender);
22
inet6_unregister_icmp_sender(ip6_icmp_send_t * fn)23 int inet6_unregister_icmp_sender(ip6_icmp_send_t *fn)
24 {
25 int ret;
26
27 ret = (cmpxchg((ip6_icmp_send_t **)&ip6_icmp_send, fn, NULL) == fn) ?
28 0 : -EINVAL;
29
30 synchronize_net();
31
32 return ret;
33 }
34 EXPORT_SYMBOL(inet6_unregister_icmp_sender);
35
__icmpv6_send(struct sk_buff * skb,u8 type,u8 code,__u32 info,const struct inet6_skb_parm * parm)36 void __icmpv6_send(struct sk_buff *skb, u8 type, u8 code, __u32 info,
37 const struct inet6_skb_parm *parm)
38 {
39 ip6_icmp_send_t *send;
40
41 rcu_read_lock();
42 send = rcu_dereference(ip6_icmp_send);
43 if (send)
44 send(skb, type, code, info, NULL, parm);
45 rcu_read_unlock();
46 }
47 EXPORT_SYMBOL(__icmpv6_send);
48 #endif
49
50 #if IS_ENABLED(CONFIG_NF_NAT)
51 #include <net/netfilter/nf_conntrack.h>
icmpv6_ndo_send(struct sk_buff * skb_in,u8 type,u8 code,__u32 info)52 void icmpv6_ndo_send(struct sk_buff *skb_in, u8 type, u8 code, __u32 info)
53 {
54 struct inet6_skb_parm parm = { 0 };
55 struct sk_buff *cloned_skb = NULL;
56 enum ip_conntrack_info ctinfo;
57 struct in6_addr orig_ip;
58 struct nf_conn *ct;
59
60 ct = nf_ct_get(skb_in, &ctinfo);
61 if (!ct || !(ct->status & IPS_SRC_NAT)) {
62 __icmpv6_send(skb_in, type, code, info, &parm);
63 return;
64 }
65
66 if (skb_shared(skb_in))
67 skb_in = cloned_skb = skb_clone(skb_in, GFP_ATOMIC);
68
69 if (unlikely(!skb_in || skb_network_header(skb_in) < skb_in->head ||
70 (skb_network_header(skb_in) + sizeof(struct ipv6hdr)) >
71 skb_tail_pointer(skb_in) || skb_ensure_writable(skb_in,
72 skb_network_offset(skb_in) + sizeof(struct ipv6hdr))))
73 goto out;
74
75 orig_ip = ipv6_hdr(skb_in)->saddr;
76 ipv6_hdr(skb_in)->saddr = ct->tuplehash[0].tuple.src.u3.in6;
77 __icmpv6_send(skb_in, type, code, info, &parm);
78 ipv6_hdr(skb_in)->saddr = orig_ip;
79 out:
80 consume_skb(cloned_skb);
81 }
82 EXPORT_SYMBOL(icmpv6_ndo_send);
83 #endif
84 #endif
85