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                 int val = 1;
  29
  30                 err = kernel_setsockopt(sock, IPPROTO_IPV6, IPV6_V6ONLY,
  31                                         (char *) &val, sizeof(val));
  32                 if (err < 0)
  33                         goto error;
  34         }
  35         if (cfg->bind_ifindex) {
  36                 err = kernel_setsockopt(sock, SOL_SOCKET, SO_BINDTOIFINDEX,
  37                                         (void *)&cfg->bind_ifindex,
  38                                         sizeof(cfg->bind_ifindex));
  39                 if (err < 0)
  40                         goto error;
  41         }
  42
  43         udp6_addr.sin6_family = AF_INET6;
  44         memcpy(&udp6_addr.sin6_addr, &cfg->local_ip6,
  45                sizeof(udp6_addr.sin6_addr));
  46         udp6_addr.sin6_port = cfg->local_udp_port;
  47         err = kernel_bind(sock, (struct sockaddr *)&udp6_addr,
  48                           sizeof(udp6_addr));
  49         if (err < 0)
  50                 goto error;
  51
  52         if (cfg->peer_udp_port) {
  53                 memset(&udp6_addr, 0, sizeof(udp6_addr));
  54                 udp6_addr.sin6_family = AF_INET6;
  55                 memcpy(&udp6_addr.sin6_addr, &cfg->peer_ip6,
  56                        sizeof(udp6_addr.sin6_addr));
  57                 udp6_addr.sin6_port = cfg->peer_udp_port;
  58                 err = kernel_connect(sock,
  59                                      (struct sockaddr *)&udp6_addr,
  60                                      sizeof(udp6_addr), 0);
  61         }
  62         if (err < 0)
  63                 goto error;
  64
  65         udp_set_no_check6_tx(sock->sk, !cfg->use_udp6_tx_checksums);
  66         udp_set_no_check6_rx(sock->sk, !cfg->use_udp6_rx_checksums);
  67
  68         *sockp = sock;
  69         return 0;
  70
  71 error:
  72         if (sock) {
  73                 kernel_sock_shutdown(sock, SHUT_RDWR);
  74                 sock_release(sock);
  75         }
  76         *sockp = NULL;
  77         return err;
  78 }
  79 EXPORT_SYMBOL_GPL(udp_sock_create6);
  80
  81 int udp_tunnel6_xmit_skb(struct dst_entry *dst, struct sock *sk,
  82                          struct sk_buff *skb,
  83                          struct net_device *dev, struct in6_addr *saddr,
  84                          struct in6_addr *daddr,
  85                          __u8 prio, __u8 ttl, __be32 label,
  86                          __be16 src_port, __be16 dst_port, bool nocheck)
  87 {
  88         struct udphdr *uh;
  89         struct ipv6hdr *ip6h;
  90
  91         __skb_push(skb, sizeof(*uh));
  92         skb_reset_transport_header(skb);
  93         uh = udp_hdr(skb);
  94
  95         uh->dest = dst_port;
  96         uh->source = src_port;
  97
  98         uh->len = htons(skb->len);
  99
 100         skb_dst_set(skb, dst);
 101
 102         udp6_set_csum(nocheck, skb, saddr, daddr, skb->len);
 103
 104         __skb_push(skb, sizeof(*ip6h));
 105         skb_reset_network_header(skb);
 106         ip6h              = ipv6_hdr(skb);
 107         ip6_flow_hdr(ip6h, prio, label);
 108         ip6h->payload_len = htons(skb->len);
 109         ip6h->nexthdr     = IPPROTO_UDP;
 110         ip6h->hop_limit   = ttl;
 111         ip6h->daddr       = *daddr;
 112         ip6h->saddr       = *saddr;
 113
 114         ip6tunnel_xmit(sk, skb, dev);
 115         return 0;
 116 }
 117 EXPORT_SYMBOL_GPL(udp_tunnel6_xmit_skb);
 118
 119 MODULE_LICENSE("GPL");