net/ipv6/ip6_udp_tunnel.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 #include <linux/module.h>
   3 #include <linux/errno.h>
   4 #include <linux/socket.h>
   5 #include <linux/udp.h>
   6 #include <linux/types.h>
   7 #include <linux/kernel.h>
   8 #include <linux/in6.h>
   9 #include <net/udp.h>
  10 #include <net/udp_tunnel.h>
  11 #include <net/net_namespace.h>
  12 #include <net/netns/generic.h>
  13 #include <net/ip6_tunnel.h>
  14 #include <net/ip6_checksum.h>
  15
  16 int udp_sock_create6(struct net *net, struct udp_port_cfg *cfg,
  17                      struct socket **sockp)
  18 {
  19         struct sockaddr_in6 udp6_addr = {};
  20         int err;
  21         struct socket *sock = NULL;
  22
  23         err = sock_create_kern(net, AF_INET6, SOCK_DGRAM, 0, &sock);
  24         if (err < 0)
  25                 goto error;
  26
  27         if (cfg->ipv6_v6only) {
  28                 err = ip6_sock_set_v6only(sock->sk);
  29                 if (err < 0)
  30                         goto error;
  31         }
  32         if (cfg->bind_ifindex) {
  33                 err = sock_bindtoindex(sock->sk, cfg->bind_ifindex, true);
  34                 if (err < 0)
  35                         goto error;
  36         }
  37
  38         udp6_addr.sin6_family = AF_INET6;
  39         memcpy(&udp6_addr.sin6_addr, &cfg->local_ip6,
  40                sizeof(udp6_addr.sin6_addr));
  41         udp6_addr.sin6_port = cfg->local_udp_port;
  42         err = kernel_bind(sock, (struct sockaddr *)&udp6_addr,
  43                           sizeof(udp6_addr));
  44         if (err < 0)
  45                 goto error;
  46
  47         if (cfg->peer_udp_port) {
  48                 memset(&udp6_addr, 0, sizeof(udp6_addr));
  49                 udp6_addr.sin6_family = AF_INET6;
  50                 memcpy(&udp6_addr.sin6_addr, &cfg->peer_ip6,
  51                        sizeof(udp6_addr.sin6_addr));
  52                 udp6_addr.sin6_port = cfg->peer_udp_port;
  53                 err = kernel_connect(sock,
  54                                      (struct sockaddr *)&udp6_addr,
  55                                      sizeof(udp6_addr), 0);
  56         }
  57         if (err < 0)
  58                 goto error;
  59
  60         udp_set_no_check6_tx(sock->sk, !cfg->use_udp6_tx_checksums);
  61         udp_set_no_check6_rx(sock->sk, !cfg->use_udp6_rx_checksums);
  62
  63         *sockp = sock;
  64         return 0;
  65
  66 error:
  67         if (sock) {
  68                 kernel_sock_shutdown(sock, SHUT_RDWR);
  69                 sock_release(sock);
  70         }
  71         *sockp = NULL;
  72         return err;
  73 }
  74 EXPORT_SYMBOL_GPL(udp_sock_create6);
  75
  76 int udp_tunnel6_xmit_skb(struct dst_entry *dst, struct sock *sk,
  77                          struct sk_buff *skb,
  78                          struct net_device *dev, struct in6_addr *saddr,
  79                          struct in6_addr *daddr,
  80                          __u8 prio, __u8 ttl, __be32 label,
  81                          __be16 src_port, __be16 dst_port, bool nocheck)
  82 {
  83         struct udphdr *uh;
  84         struct ipv6hdr *ip6h;
  85
  86         __skb_push(skb, sizeof(*uh));
  87         skb_reset_transport_header(skb);
  88         uh = udp_hdr(skb);
  89
  90         uh->dest = dst_port;
  91         uh->source = src_port;
  92
  93         uh->len = htons(skb->len);
  94
  95         skb_dst_set(skb, dst);
  96
  97         udp6_set_csum(nocheck, skb, saddr, daddr, skb->len);
  98
  99         __skb_push(skb, sizeof(*ip6h));
 100         skb_reset_network_header(skb);
 101         ip6h              = ipv6_hdr(skb);
 102         ip6_flow_hdr(ip6h, prio, label);
 103         ip6h->payload_len = htons(skb->len);
 104         ip6h->nexthdr     = IPPROTO_UDP;
 105         ip6h->hop_limit   = ttl;
 106         ip6h->daddr       = *daddr;
 107         ip6h->saddr       = *saddr;
 108
 109         ip6tunnel_xmit(sk, skb, dev);
 110         return 0;
 111 }
 112 EXPORT_SYMBOL_GPL(udp_tunnel6_xmit_skb);
 113
 114 MODULE_LICENSE("GPL");