1 /* 2 * IPv6 library code, needed by static components when full IPv6 support is 3 * not configured or static. These functions are needed by GSO/GRO implementation. 4 */ 5 #include <linux/export.h> 6 #include <net/ipv6.h> 7 #include <net/ip6_fib.h> 8 #include <net/addrconf.h> 9 10 void ipv6_select_ident(struct frag_hdr *fhdr, struct rt6_info *rt) 11 { 12 static atomic_t ipv6_fragmentation_id; 13 int old, new; 14 15 #if IS_ENABLED(CONFIG_IPV6) 16 if (rt && !(rt->dst.flags & DST_NOPEER)) { 17 struct inet_peer *peer; 18 struct net *net; 19 20 net = dev_net(rt->dst.dev); 21 peer = inet_getpeer_v6(net->ipv6.peers, &rt->rt6i_dst.addr, 1); 22 if (peer) { 23 fhdr->identification = htonl(inet_getid(peer, 0)); 24 inet_putpeer(peer); 25 return; 26 } 27 } 28 #endif 29 do { 30 old = atomic_read(&ipv6_fragmentation_id); 31 new = old + 1; 32 if (!new) 33 new = 1; 34 } while (atomic_cmpxchg(&ipv6_fragmentation_id, old, new) != old); 35 fhdr->identification = htonl(new); 36 } 37 EXPORT_SYMBOL(ipv6_select_ident); 38 39 int ip6_find_1stfragopt(struct sk_buff *skb, u8 **nexthdr) 40 { 41 u16 offset = sizeof(struct ipv6hdr); 42 struct ipv6_opt_hdr *exthdr = 43 (struct ipv6_opt_hdr *)(ipv6_hdr(skb) + 1); 44 unsigned int packet_len = skb_tail_pointer(skb) - 45 skb_network_header(skb); 46 int found_rhdr = 0; 47 *nexthdr = &ipv6_hdr(skb)->nexthdr; 48 49 while (offset + 1 <= packet_len) { 50 51 switch (**nexthdr) { 52 53 case NEXTHDR_HOP: 54 break; 55 case NEXTHDR_ROUTING: 56 found_rhdr = 1; 57 break; 58 case NEXTHDR_DEST: 59 #if IS_ENABLED(CONFIG_IPV6_MIP6) 60 if (ipv6_find_tlv(skb, offset, IPV6_TLV_HAO) >= 0) 61 break; 62 #endif 63 if (found_rhdr) 64 return offset; 65 break; 66 default : 67 return offset; 68 } 69 70 offset += ipv6_optlen(exthdr); 71 *nexthdr = &exthdr->nexthdr; 72 exthdr = (struct ipv6_opt_hdr *)(skb_network_header(skb) + 73 offset); 74 } 75 76 return offset; 77 } 78 EXPORT_SYMBOL(ip6_find_1stfragopt); 79 80 #if IS_ENABLED(CONFIG_IPV6) 81 int ip6_dst_hoplimit(struct dst_entry *dst) 82 { 83 int hoplimit = dst_metric_raw(dst, RTAX_HOPLIMIT); 84 if (hoplimit == 0) { 85 struct net_device *dev = dst->dev; 86 struct inet6_dev *idev; 87 88 rcu_read_lock(); 89 idev = __in6_dev_get(dev); 90 if (idev) 91 hoplimit = idev->cnf.hop_limit; 92 else 93 hoplimit = dev_net(dev)->ipv6.devconf_all->hop_limit; 94 rcu_read_unlock(); 95 } 96 return hoplimit; 97 } 98 EXPORT_SYMBOL(ip6_dst_hoplimit); 99 #endif 100 101 int __ip6_local_out(struct sk_buff *skb) 102 { 103 int len; 104 105 len = skb->len - sizeof(struct ipv6hdr); 106 if (len > IPV6_MAXPLEN) 107 len = 0; 108 ipv6_hdr(skb)->payload_len = htons(len); 109 110 return nf_hook(NFPROTO_IPV6, NF_INET_LOCAL_OUT, skb, NULL, 111 skb_dst(skb)->dev, dst_output); 112 } 113 EXPORT_SYMBOL_GPL(__ip6_local_out); 114 115 int ip6_local_out(struct sk_buff *skb) 116 { 117 int err; 118 119 err = __ip6_local_out(skb); 120 if (likely(err == 1)) 121 err = dst_output(skb); 122 123 return err; 124 } 125 EXPORT_SYMBOL_GPL(ip6_local_out); 126