1262 lines
28 KiB
C
1262 lines
28 KiB
C
/* GTP according to GSM TS 09.60 / 3GPP TS 29.060 */
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/* (C) 2012-2014 by sysmocom - s.f.m.c. GmbH
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* Author: Harald Welte <hwelte@sysmocom.de>
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
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*/
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#include <linux/module.h>
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#include <linux/version.h>
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#include <linux/skbuff.h>
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#include <linux/udp.h>
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#include <linux/rculist.h>
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#include <linux/jhash.h>
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#include <linux/if_tunnel.h>
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#include <net/protocol.h>
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#include <net/ip.h>
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#include <net/udp.h>
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#include <net/icmp.h>
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#include <net/xfrm.h>
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#include <net/genetlink.h>
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#include "gtp.h"
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#include "gtp_nl.h"
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static u32 gtp_h_initval;
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struct pdp_ctx {
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struct hlist_node hlist_tid;
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struct hlist_node hlist_addr;
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u64 tid;
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u8 gtp_version;
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u16 af;
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union {
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struct in6_addr ip6;
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struct in_addr ip4;
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} ms_addr;
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union {
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struct in6_addr ip6;
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struct in_addr ip4;
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} sgsn_addr;
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/* user plane and control plane address of remote GSN */
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struct sockaddr remote_c;
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struct sockaddr remote_u;
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u16 flow;
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atomic_t tx_seq;
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struct rcu_head rcu_head;
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};
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/* One local instance of the GTP code base */
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struct gtp_instance {
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struct list_head list;
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bool socket_enabled;
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/* address for local UDP socket */
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struct sockaddr_in gtp0_addr;
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struct sockaddr_in gtp1u_addr;
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/* the socket */
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struct socket *sock0;
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struct socket *sock1u;
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struct net_device *dev;
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struct net_device *real_dev;
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unsigned int hash_size;
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struct hlist_head *tid_hash;
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struct hlist_head *addr_hash;
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};
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static LIST_HEAD(gtp_instance_list); /* XXX netns */
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static inline u32 gtp0_hashfn(u64 tid)
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{
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u32 *tid32 = (u32 *) &tid;
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return jhash_2words(tid32[0], tid32[1], gtp_h_initval);
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}
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static inline u32 gtp1u_hashfn(u32 tid)
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{
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return jhash_1word(tid, gtp_h_initval);
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}
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static inline u32 ipv4_hashfn(u32 ip)
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{
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return jhash_1word(ip, gtp_h_initval);
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}
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static inline u32 ipv6_hashfn(struct in6_addr *ip6)
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{
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return jhash2((const u32 *) &ip6->s6_addr32, sizeof(*ip6)/4, gtp_h_initval);
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}
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/* resolve a PDP context structure based on the 64bit TID */
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static struct pdp_ctx *gtp0_pdp_find(struct gtp_instance *gti, u64 tid)
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{
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struct hlist_head *head;
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struct pdp_ctx *pdp;
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head = >i->tid_hash[gtp0_hashfn(tid) % gti->hash_size];
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hlist_for_each_entry_rcu(pdp, head, hlist_tid) {
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if (pdp->gtp_version == GTP_V0 && pdp->tid == tid)
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return pdp;
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}
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return NULL;
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}
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/* resolve a PDP context structure based on the 32bit TEI */
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static struct pdp_ctx *gtp1_pdp_find(struct gtp_instance *gti, u32 tid)
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{
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struct hlist_head *head;
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struct pdp_ctx *pdp;
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head = >i->tid_hash[gtp1u_hashfn(tid) % gti->hash_size];
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hlist_for_each_entry_rcu(pdp, head, hlist_tid) {
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if (pdp->gtp_version == GTP_V1 && pdp->tid == tid)
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return pdp;
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}
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return NULL;
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}
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/* resolve a PDP context based on IPv4 address of MS */
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static struct pdp_ctx *ipv4_pdp_find(struct gtp_instance *gti,
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u32 ms_addr)
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{
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struct hlist_head *head;
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struct pdp_ctx *pdp;
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head = >i->addr_hash[ipv4_hashfn(ms_addr) % gti->hash_size];
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hlist_for_each_entry_rcu(pdp, head, hlist_addr) {
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pr_info("af %u : pdp->ms %pI4 == ms %pI4\n",
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pdp->af, &pdp->ms_addr.ip4, &ms_addr);
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if (pdp->af == AF_INET && pdp->ms_addr.ip4.s_addr == ms_addr)
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return pdp;
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}
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return NULL;
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}
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/* resolve a PDP context based on IPv6 address of MS */
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static struct pdp_ctx *ipv6_pdp_find(struct gtp_instance *gti,
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struct in6_addr *ms_addr)
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{
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struct hlist_head *head;
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struct pdp_ctx *pdp;
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head = >i->addr_hash[ipv6_hashfn(ms_addr) % gti->hash_size];
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hlist_for_each_entry_rcu(pdp, head, hlist_addr) {
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if (pdp->af == AF_INET6 &&
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!memcmp(&pdp->ms_addr.ip6, ms_addr, sizeof(*ms_addr)))
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return pdp;
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}
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return NULL;
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}
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/* resolve the GTP instance for a given sock */
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static inline struct gtp_instance *sk_to_gti(struct sock *sk)
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{
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struct gtp_instance *gti;
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if (!sk)
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return NULL;
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sock_hold(sk);
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gti = (struct gtp_instance *) sk->sk_user_data;
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if (!gti) {
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sock_put(sk);
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return NULL;
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}
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return gti;
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}
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/* Check if the inner IP header has the source address assigned to the
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* current MS.
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*/
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static bool gtp_check_src_ms(struct sk_buff *skb, struct pdp_ctx *pctx)
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{
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bool ret = false;
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if (skb->protocol == ntohs(ETH_P_IP)) {
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struct iphdr *iph;
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if (!pskb_may_pull(skb, sizeof(struct iphdr)))
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return false;
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iph = (struct iphdr *)skb->data;
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ret = (iph->saddr != pctx->ms_addr.ip4.s_addr);
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} else if (skb->protocol == ntohs(ETH_P_IPV6)) {
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struct ipv6hdr *ip6h;
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if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
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return false;
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ip6h = (struct ipv6hdr *)skb->data;
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ret = memcmp(&ip6h->saddr, &pctx->ms_addr.ip6,
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sizeof(struct in6_addr)) == 0;
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}
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return ret;
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}
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static int gtp0_udp_encap_recv(struct gtp_instance *gti, struct sk_buff *skb)
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{
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struct gtp0_header *gtp0;
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struct pdp_ctx *pctx;
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u64 tid;
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pr_info("gtp0 udp received\n");
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gtp0 = (struct gtp0_header *)skb->data;
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/* check for GTP Version 0 */
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if ((gtp0->flags >> 5) != 0)
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goto out;
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/* check if it is T-PDU. if not -> userspace */
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if (gtp0->type != GTP_TPDU)
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goto out;
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/* look-up the PDP context for the Tunnel ID */
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tid = be64_to_cpu(gtp0->tid);
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rcu_read_lock();
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pctx = gtp0_pdp_find(gti, tid);
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if (!pctx)
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goto out_rcu;
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/* get rid of the GTP header */
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__skb_pull(skb, sizeof(*gtp0));
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if (!gtp_check_src_ms(skb, pctx))
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goto out_rcu;
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rcu_read_unlock();
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return 0;
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out_rcu:
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rcu_read_unlock();
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out:
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return -1;
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}
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static int gtp1u_udp_encap_recv(struct gtp_instance *gti, struct sk_buff *skb)
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{
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struct gtp1_header *gtp1;
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struct pdp_ctx *pctx;
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u32 tid;
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unsigned int min_len = sizeof(*gtp1);
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pr_info("gtp1 udp received\n");
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/* check for sufficient header size */
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if (!pskb_may_pull(skb, sizeof(*gtp1)))
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goto out;
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gtp1 = (struct gtp1_header *)skb->data;
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/* check for GTP Version 1 */
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if ((gtp1->flags >> 5) != GTP_V1)
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goto out;
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/* FIXME: a look-up table might be faster than computing the
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* length iteratively */
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/* sequence number present */
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if (gtp1->flags & 0x02)
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min_len += 2;
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/* N-PDU number present */
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if (gtp1->flags & 0x01)
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min_len++;
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/* next extension header type present */
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if (gtp1->flags & 0x04)
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min_len += 1;
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/* check if it is T-PDU. */
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if (gtp1->type != GTP_TPDU)
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goto out;
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/* check for sufficient header size */
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if (!pskb_may_pull(skb, sizeof(struct udphdr) + min_len))
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goto out;
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/* FIXME: actually take care of extension header chain */
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/* look-up the PDP context for the Tunnel ID */
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tid = ntohl(gtp1->tid);
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rcu_read_lock();
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pctx = gtp1_pdp_find(gti, tid);
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if (!pctx)
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goto out_rcu;
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/* get rid of the GTP header */
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__skb_pull(skb, sizeof(*gtp1));
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if (!gtp_check_src_ms(skb, pctx))
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goto out_rcu;
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rcu_read_unlock();
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return 0;
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out_rcu:
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rcu_read_unlock();
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out:
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return -1;
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}
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/* UDP encapsulation receive handler. See net/ipv4/udp.c.
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* Return codes: 0: success, <0: error, >0: passed up to userspace UDP.
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*/
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static int gtp_udp_encap_recv(struct sock *sk, struct sk_buff *skb)
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{
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struct gtp_instance *gti;
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int ret;
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pr_info("gtp udp received\n");
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/* resolve the GTP instance to which the socket belongs */
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gti = sk_to_gti(sk);
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if (!gti)
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goto user;
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/* UDP verifies the packet length, but this may be fragmented, so make
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* sure the UDP header is linear.
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*/
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if (!pskb_may_pull(skb, sizeof(struct udphdr)))
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goto user_put;
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__skb_pull(skb, sizeof(struct udphdr));
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switch (udp_sk(sk)->encap_type) {
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case UDP_ENCAP_GTP0:
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ret = gtp0_udp_encap_recv(gti, skb);
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break;
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case UDP_ENCAP_GTP1U:
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ret = gtp1u_udp_encap_recv(gti, skb);
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break;
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default:
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ret = -1; /* shouldn't happen */
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}
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/* Not a valid GTP packet, drop it. */
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if (unlikely(ret < 0))
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goto drop;
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/* Now that the UDP and the GTP header have been removed, set up the
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* new network header. This is required by the upper later to
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* calculate the transport header.
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*/
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skb_reset_network_header(skb);
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/* re-submit via virtual tunnel device into regular network stack */
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secpath_reset(skb);
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skb_dst_drop(skb);
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nf_reset(skb);
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skb->dev = gti->dev;
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/* Force the upper layers to verify it. */
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skb->ip_summed = CHECKSUM_NONE;
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netif_rx(skb);
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sock_put(sk);
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return 0;
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drop:
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kfree_skb(skb);
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return 0;
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user_put:
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sock_put(sk);
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user:
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return 1;
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}
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static int gtp_dev_init(struct net_device *dev)
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{
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struct gtp_instance *gti = netdev_priv(dev);
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dev->flags = IFF_NOARP;
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gti->dev = dev;
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dev->tstats = alloc_percpu(struct pcpu_sw_netstats);
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if (!dev->tstats)
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return -ENOMEM;
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return 0;
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}
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static void gtp_dev_uninit(struct net_device *dev)
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{
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free_percpu(dev->tstats);
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}
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#define IP_UDP_LEN (sizeof(struct iphdr) + sizeof(struct udphdr))
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static struct rtable *
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ip4_route_output_gtp(struct net *net, struct flowi4 *fl4,
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__be32 daddr, __be32 saddr, __u8 tos, int oif)
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{
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memset(fl4, 0, sizeof(*fl4));
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fl4->flowi4_oif = oif;
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fl4->daddr = daddr;
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fl4->saddr = saddr;
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fl4->flowi4_tos = tos;
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fl4->flowi4_proto = IPPROTO_UDP;
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return ip_route_output_key(net, fl4);
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}
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static inline void
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gtp0_push_header(struct sk_buff *skb, struct pdp_ctx *pctx, int payload_len)
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{
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struct gtp0_header *gtp0;
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/* ensure there is sufficient headroom */
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skb_cow(skb, sizeof(*gtp0) + IP_UDP_LEN);
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gtp0 = (struct gtp0_header *) skb_push(skb, sizeof(*gtp0));
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gtp0->flags = 0x1e; /* V0, GTP-non-prime */
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gtp0->type = GTP_TPDU;
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gtp0->length = htons(payload_len);
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gtp0->seq = htons((atomic_inc_return(&pctx->tx_seq)-1) % 0xffff);
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gtp0->flow = htonl(pctx->flow);
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gtp0->number = 0xFF;
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gtp0->spare[0] = gtp0->spare[1] = gtp0->spare[2] = 0xFF;
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gtp0->tid = cpu_to_be64(pctx->tid);
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}
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static inline void
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gtp1_push_header(struct sk_buff *skb, struct pdp_ctx *pctx, int payload_len)
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{
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struct gtp1_header *gtp1;
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/* ensure there is sufficient headroom */
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skb_cow(skb, sizeof(*gtp1) + IP_UDP_LEN);
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gtp1 = (struct gtp1_header *) skb_push(skb, sizeof(*gtp1));
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gtp1->flags = 0x10; /* V1, GTP-non-prime */
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gtp1->type = GTP_TPDU;
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gtp1->length = htons(payload_len);
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gtp1->tid = htonl((u32)pctx->tid);
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}
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/* From Linux kernel 3.13: iptunnel_xmit_stats() */
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static inline void
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gtp_iptunnel_xmit_stats(int err, struct net_device_stats *err_stats,
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struct pcpu_sw_netstats __percpu *stats)
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{
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if (err > 0) {
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struct pcpu_sw_netstats *tstats = this_cpu_ptr(stats);
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u64_stats_update_begin(&tstats->syncp);
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tstats->tx_bytes += err;
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tstats->tx_packets++;
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u64_stats_update_end(&tstats->syncp);
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} else if (err < 0) {
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err_stats->tx_errors++;
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err_stats->tx_aborted_errors++;
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} else {
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err_stats->tx_dropped++;
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}
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}
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|
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static netdev_tx_t gtp_dev_xmit(struct sk_buff *skb, struct net_device *dev)
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{
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struct gtp_instance *gti = netdev_priv(dev);
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struct pdp_ctx *pctx = NULL;
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struct iphdr *old_iph, *iph;
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struct ipv6hdr *old_iph6;
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struct udphdr *uh;
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unsigned int payload_len;
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int df, mtu, err;
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struct rtable *rt = NULL;
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struct flowi4 fl4;
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struct net_device *tdev;
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struct inet_sock *inet;
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/* UDP socket not initialized, skip */
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if (!gti->sock0) {
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pr_info("xmit: no socket / need cfg, skipping\n");
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return NETDEV_TX_OK;
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}
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inet = inet_sk(gti->sock0->sk);
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|
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/* read the IP desination address and resolve the PDP context.
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* Prepend PDP header with TEI/TID from PDP ctx */
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rcu_read_lock();
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if (skb->protocol == htons(ETH_P_IP)) {
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old_iph = ip_hdr(skb);
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pctx = ipv4_pdp_find(gti, old_iph->daddr);
|
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} else if (skb->protocol == htons(ETH_P_IPV6)) {
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old_iph6 = ipv6_hdr(skb);
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pctx = ipv6_pdp_find(gti, &old_iph6->daddr);
|
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}
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|
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if (!pctx) {
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rcu_read_unlock();
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pr_info("no pdp ctx found, skipping\n");
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return NETDEV_TX_OK;
|
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}
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|
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pr_info("found pdp ctx %p\n", pctx);
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|
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/* Obtain route for the new encapsulated GTP packet */
|
|
rt = ip4_route_output_gtp(dev_net(dev), &fl4,
|
|
pctx->sgsn_addr.ip4.s_addr,
|
|
inet->inet_saddr, 0,
|
|
gti->real_dev->ifindex);
|
|
if (IS_ERR(rt)) {
|
|
pr_info("no rt found, skipping\n");
|
|
dev->stats.tx_carrier_errors++;
|
|
goto tx_error;
|
|
}
|
|
tdev = rt->dst.dev;
|
|
|
|
/* There is a routing loop */
|
|
if (tdev == dev) {
|
|
pr_info("rt loop, skipping\n");
|
|
ip_rt_put(rt);
|
|
dev->stats.collisions++;
|
|
goto tx_error;
|
|
}
|
|
|
|
memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
|
|
IPCB(skb)->flags &= ~(IPSKB_XFRM_TUNNEL_SIZE | IPSKB_XFRM_TRANSFORMED |
|
|
IPSKB_REROUTED);
|
|
skb_dst_drop(skb);
|
|
skb_dst_set(skb, &rt->dst);
|
|
|
|
old_iph = ip_hdr(skb);
|
|
df = old_iph->frag_off;
|
|
if (df)
|
|
// XXX: tunnel->hlen: it depends on GTP0 / GTP1
|
|
mtu = dst_mtu(&rt->dst) - dev->hard_header_len -
|
|
sizeof(struct udphdr) - sizeof(struct gtp0_header);
|
|
else
|
|
mtu = skb_dst(skb) ? dst_mtu(skb_dst(skb)) : dev->mtu;
|
|
|
|
if (skb_dst(skb))
|
|
skb_dst(skb)->ops->update_pmtu(skb_dst(skb), NULL, skb, mtu);
|
|
|
|
if (skb->protocol == htons(ETH_P_IP)) {
|
|
df |= (old_iph->frag_off & htons(IP_DF));
|
|
|
|
if ((old_iph->frag_off & htons(IP_DF)) &&
|
|
mtu < ntohs(old_iph->tot_len)) {
|
|
icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
|
|
htonl(mtu));
|
|
ip_rt_put(rt);
|
|
goto tx_error;
|
|
}
|
|
#if IS_ENABLED(CONFIG_IPV6)
|
|
} else if (skb->protocol == htons(ETH_P_IPV6)) {
|
|
//#warning FIXME implement IPv6
|
|
}
|
|
#endif
|
|
|
|
/* Annotate length of the encapsulated packet */
|
|
payload_len = skb->len;
|
|
|
|
/* Push down GTP header */
|
|
switch (pctx->gtp_version) {
|
|
case GTP_V0:
|
|
gtp0_push_header(skb, pctx, payload_len);
|
|
break;
|
|
case GTP_V1:
|
|
gtp1_push_header(skb, pctx, payload_len);
|
|
break;
|
|
}
|
|
|
|
/* Push down and install the UDP header. */
|
|
skb_push(skb, sizeof(struct udphdr));
|
|
skb_reset_transport_header(skb);
|
|
|
|
uh = udp_hdr(skb);
|
|
if (pctx->gtp_version == 0)
|
|
uh->source = uh->dest = htons(GTP0_PORT);
|
|
else
|
|
uh->source = uh->dest = htons(GTP1U_PORT);
|
|
|
|
uh->len = htons(sizeof(struct udphdr) + payload_len);
|
|
uh->check = 0;
|
|
|
|
pr_info("gtp -> UDP src: %u dst: %u (len %u)\n",
|
|
ntohs(uh->source), ntohs(uh->dest), ntohs(uh->len));
|
|
|
|
/* Push down and install the IP header. Similar to iptunnel_xmit() */
|
|
skb_push(skb, sizeof(struct iphdr));
|
|
skb_reset_network_header(skb);
|
|
|
|
iph = ip_hdr(skb);
|
|
|
|
iph->version = 4;
|
|
iph->ihl = sizeof(struct iphdr) >> 2;
|
|
iph->frag_off = old_iph->frag_off;
|
|
iph->protocol = IPPROTO_UDP;
|
|
iph->tos = old_iph->tos;
|
|
iph->daddr = fl4.daddr;
|
|
iph->saddr = fl4.saddr;
|
|
iph->ttl = ip4_dst_hoplimit(&rt->dst);
|
|
|
|
pr_info("gtp -> IP src: %pI4 dst: %pI4\n", &iph->saddr, &iph->daddr);
|
|
|
|
rcu_read_unlock();
|
|
|
|
nf_reset(skb);
|
|
|
|
err = ip_local_out(skb);
|
|
gtp_iptunnel_xmit_stats(err, &dev->stats, dev->tstats);
|
|
|
|
return NETDEV_TX_OK;
|
|
tx_error:
|
|
rcu_read_unlock();
|
|
pr_info("no route to reach destination\n");
|
|
dev->stats.tx_errors++;
|
|
dev_kfree_skb(skb);
|
|
return NETDEV_TX_OK;
|
|
}
|
|
|
|
static const struct net_device_ops gtp_netdev_ops = {
|
|
.ndo_init = gtp_dev_init,
|
|
.ndo_uninit = gtp_dev_uninit,
|
|
.ndo_start_xmit = gtp_dev_xmit,
|
|
};
|
|
|
|
static void gtp_link_setup(struct net_device *dev)
|
|
{
|
|
dev->priv_flags &= ~(IFF_TX_SKB_SHARING);
|
|
dev->tx_queue_len = 0;
|
|
|
|
dev->netdev_ops = >p_netdev_ops;
|
|
dev->destructor = free_netdev;
|
|
}
|
|
|
|
static int gtp_newlink(struct net *src_net, struct net_device *dev,
|
|
struct nlattr *tb[], struct nlattr *data[])
|
|
{
|
|
struct net_device *real_dev;
|
|
struct gtp_instance *gti;
|
|
int err;
|
|
|
|
pr_info("gtp_newlink\n");
|
|
|
|
if (!tb[IFLA_LINK])
|
|
return -EINVAL;
|
|
|
|
real_dev = __dev_get_by_index(src_net, nla_get_u32(tb[IFLA_LINK]));
|
|
if (!real_dev)
|
|
return -ENODEV;
|
|
|
|
dev_hold(real_dev);
|
|
|
|
if (!tb[IFLA_MTU])
|
|
dev->mtu = real_dev->mtu;
|
|
else if (dev->mtu > real_dev->mtu)
|
|
return -EINVAL;
|
|
|
|
gti = netdev_priv(dev);
|
|
gti->real_dev = real_dev;
|
|
|
|
err = register_netdevice(dev);
|
|
if (err < 0)
|
|
goto err1;
|
|
|
|
list_add_rcu(>i->list, >p_instance_list);
|
|
|
|
pr_info("registered new %s interface\n", dev->name);
|
|
|
|
return 0;
|
|
err1:
|
|
pr_info("failed to register new netdev %d\n", err);
|
|
return err;
|
|
}
|
|
|
|
static void gtp_dellink(struct net_device *dev, struct list_head *head)
|
|
{
|
|
struct gtp_instance *gti = netdev_priv(dev);
|
|
|
|
dev_put(gti->real_dev);
|
|
list_del_rcu(>i->list);
|
|
unregister_netdevice_queue(dev, head);
|
|
}
|
|
|
|
static struct rtnl_link_ops gtp_link_ops __read_mostly = {
|
|
.kind = "gtp",
|
|
.priv_size = sizeof(struct gtp_instance),
|
|
.setup = gtp_link_setup,
|
|
.newlink = gtp_newlink,
|
|
.dellink = gtp_dellink,
|
|
};
|
|
|
|
static int gtp_hashtable_new(struct gtp_instance *gti, int hsize)
|
|
{
|
|
int i;
|
|
|
|
gti->addr_hash = kmalloc(sizeof(struct hlist_head) * hsize, GFP_KERNEL);
|
|
if (gti->addr_hash == NULL)
|
|
return -ENOMEM;
|
|
|
|
gti->tid_hash= kmalloc(sizeof(struct hlist_head) * hsize, GFP_KERNEL);
|
|
if (gti->tid_hash == NULL)
|
|
goto err1;
|
|
|
|
gti->hash_size = hsize;
|
|
|
|
for (i = 0; i < hsize; i++) {
|
|
INIT_HLIST_HEAD(>i->addr_hash[i]);
|
|
INIT_HLIST_HEAD(>i->tid_hash[i]);
|
|
}
|
|
return 0;
|
|
err1:
|
|
kfree(gti->addr_hash);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
static void gtp_hashtable_free(struct gtp_instance *gti)
|
|
{
|
|
struct pdp_ctx *pctx;
|
|
int i;
|
|
|
|
for (i = 0; i < gti->hash_size; i++) {
|
|
hlist_for_each_entry_rcu(pctx, >i->tid_hash[i], hlist_tid) {
|
|
hlist_del_rcu(&pctx->hlist_tid);
|
|
hlist_del_rcu(&pctx->hlist_addr);
|
|
kfree_rcu(pctx, rcu_head);
|
|
}
|
|
}
|
|
synchronize_rcu();
|
|
kfree(gti->addr_hash);
|
|
kfree(gti->tid_hash);
|
|
}
|
|
|
|
static int gtp_create_bind_sock(struct gtp_instance *gti)
|
|
{
|
|
int rc;
|
|
struct sockaddr_in sin;
|
|
struct sock *sk;
|
|
|
|
/* Create and bind the socket for GTP0 */
|
|
rc = sock_create(AF_INET, SOCK_DGRAM, IPPROTO_UDP, >i->sock0);
|
|
if (rc < 0)
|
|
goto out;
|
|
|
|
memset(&sin, 0, sizeof(sin));
|
|
sin.sin_family = AF_INET;
|
|
sin.sin_port = htons(GTP0_PORT);
|
|
rc = kernel_bind(gti->sock0, (struct sockaddr *) &sin, sizeof(sin));
|
|
if (rc < 0)
|
|
goto out;
|
|
|
|
sk = gti->sock0->sk;
|
|
udp_sk(sk)->encap_type = UDP_ENCAP_GTP0;
|
|
udp_sk(sk)->encap_rcv = gtp_udp_encap_recv;
|
|
sk->sk_user_data = gti;
|
|
udp_encap_enable();
|
|
|
|
/* Create and bind the socket for GTP1 user-plane */
|
|
rc = sock_create(AF_INET, SOCK_DGRAM, IPPROTO_UDP, >i->sock1u);
|
|
if (rc < 0)
|
|
goto out_free0;
|
|
|
|
memset(&sin, 0, sizeof(sin));
|
|
sin.sin_family = AF_INET;
|
|
sin.sin_port = htons(GTP1U_PORT);
|
|
rc = kernel_bind(gti->sock1u, (struct sockaddr *) &sin, sizeof(sin));
|
|
if (rc < 0)
|
|
goto out_free1;
|
|
|
|
sk = gti->sock1u->sk;
|
|
udp_sk(sk)->encap_type = UDP_ENCAP_GTP1U;
|
|
udp_sk(sk)->encap_rcv = gtp_udp_encap_recv;
|
|
sk->sk_user_data = gti;
|
|
|
|
return 0;
|
|
|
|
out_free1:
|
|
kernel_sock_shutdown(gti->sock1u, SHUT_RDWR);
|
|
sk_release_kernel(gti->sock1u->sk);
|
|
out_free0:
|
|
kernel_sock_shutdown(gti->sock0, SHUT_RDWR);
|
|
sk_release_kernel(gti->sock0->sk);
|
|
out:
|
|
return rc;
|
|
}
|
|
|
|
static void gtp_destroy_bind_sock(struct gtp_instance *gti)
|
|
{
|
|
if (gti->sock1u) {
|
|
kernel_sock_shutdown(gti->sock1u, SHUT_RDWR);
|
|
sk_release_kernel(gti->sock1u->sk);
|
|
}
|
|
if (gti->sock0) {
|
|
kernel_sock_shutdown(gti->sock0, SHUT_RDWR);
|
|
sk_release_kernel(gti->sock0->sk);
|
|
}
|
|
}
|
|
|
|
static struct net_device *gtp_find_dev(int ifindex)
|
|
{
|
|
struct gtp_instance *gti;
|
|
|
|
list_for_each_entry_rcu(gti, >p_instance_list, list) {
|
|
if (ifindex == gti->dev->ifindex)
|
|
return gti->dev;
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
/* This configuration routine sets up the hashtable and it links the UDP
|
|
* socket to the device.
|
|
*/
|
|
static int gtp_genl_cfg_new(struct sk_buff *skb, struct genl_info *info)
|
|
{
|
|
struct net_device *dev;
|
|
struct gtp_instance *gti;
|
|
int err;
|
|
|
|
if (!info->attrs[GTPA_LINK])
|
|
return -EINVAL;
|
|
|
|
/* Check if there's an existing gtpX device to configure */
|
|
dev = gtp_find_dev(nla_get_u32(info->attrs[GTPA_CFG_LINK]));
|
|
if (dev == NULL)
|
|
return -ENODEV;
|
|
|
|
gti = netdev_priv(dev);
|
|
|
|
/* Create the UDP socket if needed */
|
|
if (info->nlhdr->nlmsg_flags & NLM_F_CREATE) {
|
|
if (gti->socket_enabled)
|
|
return -EBUSY;
|
|
|
|
if (!info->attrs[GTPA_CFG_LOCAL_ADDR_IPV4])
|
|
return -EINVAL;
|
|
|
|
gti->gtp0_addr.sin_addr.s_addr =
|
|
gti->gtp1u_addr.sin_addr.s_addr =
|
|
nla_get_u32(info->attrs[GTPA_CFG_LOCAL_ADDR_IPV4]);
|
|
|
|
/* XXX fix hardcoded hashtable size */
|
|
err = gtp_hashtable_new(gti, 1024);
|
|
if (err < 0)
|
|
return err;
|
|
|
|
err = gtp_create_bind_sock(gti);
|
|
if (err < 0)
|
|
goto err1;
|
|
|
|
gti->socket_enabled = true;
|
|
} else {
|
|
/* XXX configuration updates not yet supported */
|
|
return -EOPNOTSUPP;
|
|
}
|
|
|
|
return 0;
|
|
err1:
|
|
gtp_hashtable_free(gti);
|
|
return err;
|
|
}
|
|
|
|
static int gtp_genl_cfg_get(struct sk_buff *skb, struct genl_info *info)
|
|
{
|
|
/* XXX */
|
|
return 0;
|
|
}
|
|
|
|
static int gtp_genl_cfg_delete(struct sk_buff *skb, struct genl_info *info)
|
|
{
|
|
struct net_device *dev;
|
|
struct gtp_instance *gti;
|
|
|
|
if (!info->attrs[GTPA_LINK])
|
|
return -EINVAL;
|
|
|
|
/* Check if there's an existing gtpX device to configure */
|
|
dev = gtp_find_dev(nla_get_u32(info->attrs[GTPA_CFG_LINK]));
|
|
if (dev == NULL)
|
|
return -ENODEV;
|
|
|
|
gti = netdev_priv(dev);
|
|
gtp_destroy_bind_sock(gti);
|
|
gtp_hashtable_free(gti);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int ipv4_pdp_add(struct gtp_instance *gti, struct genl_info *info)
|
|
{
|
|
u32 hash_ms;
|
|
u32 hash_tid;
|
|
struct pdp_ctx *pctx;
|
|
u32 gtp_version, link, sgsn_addr, ms_addr, tid;
|
|
bool found = false;
|
|
|
|
gtp_version = nla_get_u32(info->attrs[GTPA_VERSION]);
|
|
switch (gtp_version) {
|
|
case GTP_V0:
|
|
case GTP_V1:
|
|
break;
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
|
|
tid = nla_get_u64(info->attrs[GTPA_TID]);
|
|
/* GTPv1 allows 32-bits tunnel IDs */
|
|
if (gtp_version == GTP_V1 && tid > UINT_MAX)
|
|
return -EINVAL;
|
|
|
|
link = nla_get_u32(info->attrs[GTPA_LINK]);
|
|
sgsn_addr = nla_get_u32(info->attrs[GTPA_SGSN_ADDRESS]);
|
|
ms_addr = nla_get_u32(info->attrs[GTPA_MS_ADDRESS]);
|
|
|
|
hash_ms = ipv4_hashfn(ms_addr) % gti->hash_size;
|
|
|
|
hlist_for_each_entry_rcu(pctx, >i->addr_hash[hash_ms], hlist_addr) {
|
|
if (pctx->ms_addr.ip4.s_addr == ms_addr) {
|
|
found = true;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (found) {
|
|
if (info->nlhdr->nlmsg_flags & NLM_F_EXCL)
|
|
return -EEXIST;
|
|
if (info->nlhdr->nlmsg_flags & NLM_F_REPLACE)
|
|
return -EOPNOTSUPP;
|
|
|
|
pctx->af = AF_INET;
|
|
pctx->gtp_version = gtp_version;
|
|
pctx->tid = tid;
|
|
pctx->sgsn_addr.ip4.s_addr = sgsn_addr;
|
|
pctx->ms_addr.ip4.s_addr = ms_addr;
|
|
|
|
pr_info("update tunnel id = %u (pdp %p)\n", tid, pctx);
|
|
|
|
return 0;
|
|
}
|
|
|
|
pctx = kmalloc(sizeof(struct pdp_ctx), GFP_KERNEL);
|
|
if (pctx == NULL)
|
|
return -ENOMEM;
|
|
|
|
pctx->af = AF_INET;
|
|
pctx->gtp_version = gtp_version;
|
|
pctx->tid = tid;
|
|
pctx->sgsn_addr.ip4.s_addr = sgsn_addr;
|
|
pctx->ms_addr.ip4.s_addr = ms_addr;
|
|
atomic_set(&pctx->tx_seq, 0);
|
|
|
|
hash_tid = ipv4_hashfn(tid) % gti->hash_size;
|
|
|
|
hlist_add_head_rcu(&pctx->hlist_addr, >i->addr_hash[hash_ms]);
|
|
hlist_add_head_rcu(&pctx->hlist_tid, >i->tid_hash[hash_tid]);
|
|
|
|
pr_info("adding tunnel id = %u (pdp %p)\n", tid, pctx);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int gtp_genl_tunnel_new(struct sk_buff *skb, struct genl_info *info)
|
|
{
|
|
struct net_device *dev;
|
|
struct gtp_instance *gti;
|
|
|
|
if (!info->attrs[GTPA_VERSION] ||
|
|
!info->attrs[GTPA_LINK] ||
|
|
!info->attrs[GTPA_SGSN_ADDRESS] ||
|
|
!info->attrs[GTPA_MS_ADDRESS] ||
|
|
!info->attrs[GTPA_TID])
|
|
return -EINVAL;
|
|
|
|
/* Check if there's an existing gtpX device to configure */
|
|
dev = gtp_find_dev(nla_get_u32(info->attrs[GTPA_LINK]));
|
|
if (dev == NULL)
|
|
return -ENODEV;
|
|
|
|
gti = netdev_priv(dev);
|
|
|
|
if (!gti->socket_enabled)
|
|
return -ENETDOWN;
|
|
|
|
return ipv4_pdp_add(gti, info);
|
|
}
|
|
|
|
static int gtp_genl_tunnel_delete(struct sk_buff *skb, struct genl_info *info)
|
|
{
|
|
struct gtp_instance *gti;
|
|
struct net_device *dev;
|
|
struct pdp_ctx *pctx;
|
|
u32 gtp_version;
|
|
u64 tid;
|
|
|
|
pr_info("deleting tunnel\n");
|
|
|
|
if (!info->attrs[GTPA_VERSION] ||
|
|
!info->attrs[GTPA_LINK] ||
|
|
!info->attrs[GTPA_SGSN_ADDRESS] ||
|
|
!info->attrs[GTPA_MS_ADDRESS] ||
|
|
!info->attrs[GTPA_TID])
|
|
return -EINVAL;
|
|
|
|
gtp_version = nla_get_u32(info->attrs[GTPA_VERSION]);
|
|
switch (gtp_version) {
|
|
case GTP_V0:
|
|
case GTP_V1:
|
|
break;
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
|
|
tid = nla_get_u64(info->attrs[GTPA_TID]);
|
|
/* GTPv1 allows 32-bits tunnel IDs */
|
|
if (gtp_version == GTP_V1 && tid > UINT_MAX)
|
|
return -EINVAL;
|
|
|
|
/* Check if there's an existing gtpX device to configure */
|
|
dev = gtp_find_dev(nla_get_u32(info->attrs[GTPA_LINK]));
|
|
if (dev == NULL)
|
|
return -ENODEV;
|
|
|
|
gti = netdev_priv(dev);
|
|
|
|
switch (gtp_version) {
|
|
case GTP_V0:
|
|
pctx = gtp0_pdp_find(gti, nla_get_u64(info->attrs[GTPA_TID]));
|
|
break;
|
|
case GTP_V1:
|
|
pctx = gtp1_pdp_find(gti, nla_get_u64(info->attrs[GTPA_TID]));
|
|
break;
|
|
}
|
|
|
|
if (pctx == NULL)
|
|
return -ENOENT;
|
|
|
|
hlist_del_rcu(&pctx->hlist_tid);
|
|
hlist_del_rcu(&pctx->hlist_addr);
|
|
kfree_rcu(pctx, rcu_head);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int gtp_genl_tunnel_get(struct sk_buff *skb, struct genl_info *info)
|
|
{
|
|
struct net_device *dev;
|
|
struct gtp_instance *gti;
|
|
|
|
pr_info("get tunnel\n");
|
|
|
|
if (!info->attrs[GTPA_VERSION] ||
|
|
!info->attrs[GTPA_LINK])
|
|
return -EINVAL;
|
|
|
|
/* Check if there's an existing gtpX device to configure */
|
|
dev = gtp_find_dev(nla_get_u32(info->attrs[GTPA_LINK]));
|
|
if (dev == NULL)
|
|
return -ENODEV;
|
|
|
|
gti = netdev_priv(dev);
|
|
|
|
if (info->attrs[GTPA_TID])
|
|
pr_info("by tid\n");
|
|
else if (info->attrs[GTPA_MS_ADDRESS])
|
|
pr_info("by ms\n");
|
|
else
|
|
return -EINVAL;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static struct genl_family gtp_genl_family = {
|
|
.id = GENL_ID_GENERATE,
|
|
.name = "gtp",
|
|
.version = 0,
|
|
.hdrsize = 0,
|
|
.maxattr = GTPA_MAX,
|
|
.netnsok = true,
|
|
};
|
|
|
|
static int
|
|
gtp_genl_fill_info(struct sk_buff *skb, u32 snd_portid, u32 snd_seq,
|
|
u32 type, struct pdp_ctx *pctx)
|
|
{
|
|
void *genlh;
|
|
|
|
genlh = genlmsg_put(skb, snd_portid, snd_seq, >p_genl_family, 0,
|
|
type);
|
|
if (genlh == NULL)
|
|
goto nlmsg_failure;
|
|
|
|
pr_info("filling info for tunnel %llu\n", pctx->tid);
|
|
|
|
if (nla_put_u32(skb, GTPA_VERSION, pctx->gtp_version) ||
|
|
nla_put_u32(skb, GTPA_SGSN_ADDRESS, pctx->sgsn_addr.ip4.s_addr) ||
|
|
nla_put_u32(skb, GTPA_MS_ADDRESS, pctx->ms_addr.ip4.s_addr) ||
|
|
nla_put_u64(skb, GTPA_TID, pctx->tid))
|
|
goto nla_put_failure;
|
|
|
|
return genlmsg_end(skb, genlh);
|
|
|
|
nlmsg_failure:
|
|
nla_put_failure:
|
|
return -EMSGSIZE;
|
|
}
|
|
|
|
static int
|
|
gtp_genl_tunnel_dump(struct sk_buff *skb, struct netlink_callback *cb)
|
|
{
|
|
int i, k = cb->args[0], ret;
|
|
unsigned long tid = cb->args[1];
|
|
struct gtp_instance *last_gti = (struct gtp_instance *)cb->args[2], *gti;
|
|
struct pdp_ctx *pctx;
|
|
|
|
if (cb->args[4])
|
|
return 0;
|
|
|
|
list_for_each_entry_rcu(gti, >p_instance_list, list) {
|
|
if (last_gti && last_gti != gti)
|
|
continue;
|
|
else
|
|
last_gti = NULL;
|
|
|
|
for (i = k; i < gti->hash_size; i++) {
|
|
hlist_for_each_entry_rcu(pctx, >i->tid_hash[i], hlist_tid) {
|
|
if (tid && tid != pctx->tid)
|
|
continue;
|
|
else
|
|
tid = 0;
|
|
|
|
ret = gtp_genl_fill_info(skb,
|
|
NETLINK_CB(cb->skb).portid,
|
|
cb->nlh->nlmsg_seq,
|
|
cb->nlh->nlmsg_type, pctx);
|
|
if (ret < 0) {
|
|
cb->args[0] = i;
|
|
cb->args[1] = pctx->tid;
|
|
cb->args[2] = (unsigned long)gti;
|
|
goto out;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
cb->args[4] = 1;
|
|
out:
|
|
return skb->len;
|
|
}
|
|
|
|
static struct nla_policy gtp_genl_policy[GTPA_MAX + 1] = {
|
|
[GTPA_VERSION] = { .type = NLA_U32, },
|
|
[GTPA_LINK] = { .type = NLA_U32, },
|
|
[GTPA_SGSN_ADDRESS] = { .type = NLA_NESTED, },
|
|
[GTPA_MS_ADDRESS] = { .type = NLA_NESTED, },
|
|
};
|
|
|
|
static const struct genl_ops gtp_genl_ops[] = {
|
|
{
|
|
.cmd = GTP_CMD_CFG_NEW,
|
|
.doit = gtp_genl_cfg_new,
|
|
.policy = gtp_genl_policy,
|
|
.flags = GENL_ADMIN_PERM,
|
|
},
|
|
{
|
|
.cmd = GTP_CMD_CFG_DELETE,
|
|
.doit = gtp_genl_cfg_delete,
|
|
.policy = gtp_genl_policy,
|
|
.flags = GENL_ADMIN_PERM,
|
|
},
|
|
{
|
|
.cmd = GTP_CMD_CFG_GET,
|
|
.doit = gtp_genl_cfg_get,
|
|
.policy = gtp_genl_policy,
|
|
.flags = GENL_ADMIN_PERM,
|
|
},
|
|
{
|
|
.cmd = GTP_CMD_TUNNEL_NEW,
|
|
.doit = gtp_genl_tunnel_new,
|
|
.policy = gtp_genl_policy,
|
|
.flags = GENL_ADMIN_PERM,
|
|
},
|
|
{
|
|
.cmd = GTP_CMD_TUNNEL_DELETE,
|
|
.doit = gtp_genl_tunnel_delete,
|
|
.policy = gtp_genl_policy,
|
|
.flags = GENL_ADMIN_PERM,
|
|
},
|
|
{
|
|
.cmd = GTP_CMD_TUNNEL_GET,
|
|
.doit = gtp_genl_tunnel_get,
|
|
.dumpit = gtp_genl_tunnel_dump,
|
|
.policy = gtp_genl_policy,
|
|
.flags = GENL_ADMIN_PERM,
|
|
},
|
|
};
|
|
|
|
static int __init gtp_init(void)
|
|
{
|
|
int err;
|
|
|
|
get_random_bytes(>p_h_initval, sizeof(gtp_h_initval));
|
|
|
|
err = genl_register_family_with_ops(>p_genl_family, gtp_genl_ops);
|
|
if (err < 0)
|
|
return err;
|
|
|
|
err = rtnl_link_register(>p_link_ops);
|
|
if (err < 0)
|
|
goto err1;
|
|
|
|
pr_info("GTP module loaded (pdp ctx size %Zd bytes)\n",
|
|
sizeof(struct pdp_ctx));
|
|
return 0;
|
|
err1:
|
|
pr_info("error loading GTP module loaded\n");
|
|
genl_unregister_family(>p_genl_family);
|
|
return err;
|
|
}
|
|
|
|
static void __exit gtp_fini(void)
|
|
{
|
|
struct gtp_instance *gti;
|
|
|
|
list_for_each_entry_rcu(gti, >p_instance_list, list) {
|
|
pr_info("delete instance gtp %p\n", gti);
|
|
gtp_destroy_bind_sock(gti);
|
|
gtp_hashtable_free(gti);
|
|
}
|
|
rtnl_link_unregister(>p_link_ops);
|
|
genl_unregister_family(>p_genl_family);
|
|
|
|
pr_info("GTP module unloaded\n");
|
|
}
|
|
|
|
module_init(gtp_init);
|
|
module_exit(gtp_fini);
|
|
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_AUTHOR("Harald Welte <hwelte@sysmocom.de>");
|
|
MODULE_ALIAS_RTNL_LINK("gtp");
|
|
MODULE_ALIAS_NETDEV("gtp0");
|