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Release 4.8 net/ipv4/ip_vti.c

Directory: net/ipv4
/*
 *      Linux NET3: IP/IP protocol decoder modified to support
 *                  virtual tunnel interface
 *
 *      Authors:
 *              Saurabh Mohan (saurabh.mohan@vyatta.com) 05/07/2012
 *
 *      This program is free software; you can redistribute it and/or
 *      modify it under the terms of the GNU General Public License
 *      as published by the Free Software Foundation; either version
 *      2 of the License, or (at your option) any later version.
 *
 */

/*
   This version of net/ipv4/ip_vti.c is cloned of net/ipv4/ipip.c

   For comments look at net/ipv4/ip_gre.c --ANK
 */


#include <linux/capability.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/uaccess.h>
#include <linux/skbuff.h>
#include <linux/netdevice.h>
#include <linux/in.h>
#include <linux/tcp.h>
#include <linux/udp.h>
#include <linux/if_arp.h>
#include <linux/init.h>
#include <linux/netfilter_ipv4.h>
#include <linux/if_ether.h>
#include <linux/icmpv6.h>

#include <net/sock.h>
#include <net/ip.h>
#include <net/icmp.h>
#include <net/ip_tunnels.h>
#include <net/inet_ecn.h>
#include <net/xfrm.h>
#include <net/net_namespace.h>
#include <net/netns/generic.h>


static struct rtnl_link_ops vti_link_ops __read_mostly;


static int vti_net_id __read_mostly;
static int vti_tunnel_init(struct net_device *dev);


static int vti_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type) { struct ip_tunnel *tunnel; const struct iphdr *iph = ip_hdr(skb); struct net *net = dev_net(skb->dev); struct ip_tunnel_net *itn = net_generic(net, vti_net_id); tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex, TUNNEL_NO_KEY, iph->saddr, iph->daddr, 0); if (tunnel) { if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) goto drop; XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4 = tunnel; return xfrm_input(skb, nexthdr, spi, encap_type); } return -EINVAL; drop: kfree_skb(skb); return 0; }

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americo wangamerico wang6243.36%125.00%
steffen klassertsteffen klassert5941.26%125.00%
saurabh mohansaurabh mohan2013.99%125.00%
christophe gouaultchristophe gouault21.40%125.00%
Total143100.00%4100.00%


static int vti_rcv(struct sk_buff *skb) { XFRM_SPI_SKB_CB(skb)->family = AF_INET; XFRM_SPI_SKB_CB(skb)->daddroff = offsetof(struct iphdr, daddr); return vti_input(skb, ip_hdr(skb)->protocol, 0, 0); }

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christophe gouaultchristophe gouault35.77%133.33%
americo wangamerico wang23.85%133.33%
Total52100.00%3100.00%


static int vti_rcv_cb(struct sk_buff *skb, int err) { unsigned short family; struct net_device *dev; struct pcpu_sw_netstats *tstats; struct xfrm_state *x; struct xfrm_mode *inner_mode; struct ip_tunnel *tunnel = XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4; u32 orig_mark = skb->mark; int ret; if (!tunnel) return 1; dev = tunnel->dev; if (err) { dev->stats.rx_errors++; dev->stats.rx_dropped++; return 0; } x = xfrm_input_state(skb); inner_mode = x->inner_mode; if (x->sel.family == AF_UNSPEC) { inner_mode = xfrm_ip2inner_mode(x, XFRM_MODE_SKB_CB(skb)->protocol); if (inner_mode == NULL) { XFRM_INC_STATS(dev_net(skb->dev), LINUX_MIB_XFRMINSTATEMODEERROR); return -EINVAL; } } family = inner_mode->afinfo->family; skb->mark = be32_to_cpu(tunnel->parms.i_key); ret = xfrm_policy_check(NULL, XFRM_POLICY_IN, skb, family); skb->mark = orig_mark; if (!ret) return -EPERM; skb_scrub_packet(skb, !net_eq(tunnel->net, dev_net(skb->dev))); skb->dev = dev; tstats = this_cpu_ptr(dev->tstats); u64_stats_update_begin(&tstats->syncp); tstats->rx_packets++; tstats->rx_bytes += skb->len; u64_stats_update_end(&tstats->syncp); return 0; }

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steffen klassertsteffen klassert13648.92%116.67%
thomas zeitlhoferthomas zeitlhofer5921.22%116.67%
alexander duyckalexander duyck3612.95%116.67%
americo wangamerico wang3412.23%116.67%
saurabh mohansaurabh mohan113.96%116.67%
christophe gouaultchristophe gouault20.72%116.67%
Total278100.00%6100.00%


static bool vti_state_check(const struct xfrm_state *x, __be32 dst, __be32 src) { xfrm_address_t *daddr = (xfrm_address_t *)&dst; xfrm_address_t *saddr = (xfrm_address_t *)&src; /* if there is no transform then this tunnel is not functional. * Or if the xfrm is not mode tunnel. */ if (!x || x->props.mode != XFRM_MODE_TUNNEL || x->props.family != AF_INET) return false; if (!dst) return xfrm_addr_equal(saddr, &x->props.saddr, AF_INET); if (!xfrm_state_addr_check(x, daddr, saddr, AF_INET)) return false; return true; }

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steffen klassertsteffen klassert105100.00%1100.00%
Total105100.00%1100.00%


static netdev_tx_t vti_xmit(struct sk_buff *skb, struct net_device *dev, struct flowi *fl) { struct ip_tunnel *tunnel = netdev_priv(dev); struct ip_tunnel_parm *parms = &tunnel->parms; struct dst_entry *dst = skb_dst(skb); struct net_device *tdev; /* Device to other host */ int err; int mtu; if (!dst) { dev->stats.tx_carrier_errors++; goto tx_error_icmp; } dst_hold(dst); dst = xfrm_lookup(tunnel->net, dst, fl, NULL, 0); if (IS_ERR(dst)) { dev->stats.tx_carrier_errors++; goto tx_error_icmp; } if (!vti_state_check(dst->xfrm, parms->iph.daddr, parms->iph.saddr)) { dev->stats.tx_carrier_errors++; dst_release(dst); goto tx_error_icmp; } tdev = dst->dev; if (tdev == dev) { dst_release(dst); dev->stats.collisions++; goto tx_error; } if (tunnel->err_count > 0) { if (time_before(jiffies, tunnel->err_time + IPTUNNEL_ERR_TIMEO)) { tunnel->err_count--; dst_link_failure(skb); } else tunnel->err_count = 0; } mtu = dst_mtu(dst); if (skb->len > mtu) { skb_dst(skb)->ops->update_pmtu(skb_dst(skb), NULL, skb, mtu); if (skb->protocol == htons(ETH_P_IP)) { icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, htonl(mtu)); } else { if (mtu < IPV6_MIN_MTU) mtu = IPV6_MIN_MTU; icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu); } dst_release(dst); goto tx_error; } skb_scrub_packet(skb, !net_eq(tunnel->net, dev_net(dev))); skb_dst_set(skb, dst); skb->dev = skb_dst(skb)->dev; err = dst_output(tunnel->net, skb->sk, skb); if (net_xmit_eval(err) == 0) err = skb->len; iptunnel_xmit_stats(dev, err); return NETDEV_TX_OK; tx_error_icmp: dst_link_failure(skb); tx_error: dev->stats.tx_errors++; kfree_skb(skb); return NETDEV_TX_OK; }

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americo wangamerico wang12629.44%19.09%
saurabh mohansaurabh mohan5713.32%19.09%
eric w. biedermaneric w. biederman81.87%218.18%
fan dufan du30.70%19.09%
pravin b shelarpravin b shelar10.23%19.09%
Total428100.00%11100.00%

/* This function assumes it is being called from dev_queue_xmit() * and that skb is filled properly by that function. */
static netdev_tx_t vti_tunnel_xmit(struct sk_buff *skb, struct net_device *dev) { struct ip_tunnel *tunnel = netdev_priv(dev); struct flowi fl; memset(&fl, 0, sizeof(fl)); switch (skb->protocol) { case htons(ETH_P_IP): xfrm_decode_session(skb, &fl, AF_INET); memset(IPCB(skb), 0, sizeof(*IPCB(skb))); break; case htons(ETH_P_IPV6): xfrm_decode_session(skb, &fl, AF_INET6); memset(IP6CB(skb), 0, sizeof(*IP6CB(skb))); break; default: dev->stats.tx_errors++; dev_kfree_skb(skb); return NETDEV_TX_OK; } /* override mark with tunnel output key */ fl.flowi_mark = be32_to_cpu(tunnel->parms.o_key); return vti_xmit(skb, dev, &fl); }

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steffen klassertsteffen klassert15091.46%150.00%
alexander duyckalexander duyck148.54%150.00%
Total164100.00%2100.00%


static int vti4_err(struct sk_buff *skb, u32 info) { __be32 spi; __u32 mark; struct xfrm_state *x; struct ip_tunnel *tunnel; struct ip_esp_hdr *esph; struct ip_auth_hdr *ah ; struct ip_comp_hdr *ipch; struct net *net = dev_net(skb->dev); const struct iphdr *iph = (const struct iphdr *)skb->data; int protocol = iph->protocol; struct ip_tunnel_net *itn = net_generic(net, vti_net_id); tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex, TUNNEL_NO_KEY, iph->daddr, iph->saddr, 0); if (!tunnel) return -1; mark = be32_to_cpu(tunnel->parms.o_key); switch (protocol) { case IPPROTO_ESP: esph = (struct ip_esp_hdr *)(skb->data+(iph->ihl<<2)); spi = esph->spi; break; case IPPROTO_AH: ah = (struct ip_auth_hdr *)(skb->data+(iph->ihl<<2)); spi = ah->spi; break; case IPPROTO_COMP: ipch = (struct ip_comp_hdr *)(skb->data+(iph->ihl<<2)); spi = htonl(ntohs(ipch->cpi)); break; default: return 0; } switch (icmp_hdr(skb)->type) { case ICMP_DEST_UNREACH: if (icmp_hdr(skb)->code != ICMP_FRAG_NEEDED) return 0; case ICMP_REDIRECT: break; default: return 0; } x = xfrm_state_lookup(net, mark, (const xfrm_address_t *)&iph->daddr, spi, protocol, AF_INET); if (!x) return 0; if (icmp_hdr(skb)->type == ICMP_DEST_UNREACH) ipv4_update_pmtu(skb, net, info, 0, 0, protocol, 0); else ipv4_redirect(skb, net, 0, 0, protocol, 0); xfrm_state_put(x); return 0; }

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americo wangamerico wang61.63%125.00%
Total367100.00%4100.00%


static int vti_tunnel_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd) { int err = 0; struct ip_tunnel_parm p; if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) return -EFAULT; if (cmd == SIOCADDTUNNEL || cmd == SIOCCHGTUNNEL) { if (p.iph.version != 4 || p.iph.protocol != IPPROTO_IPIP || p.iph.ihl != 5) return -EINVAL; } if (!(p.i_flags & GRE_KEY)) p.i_key = 0; if (!(p.o_flags & GRE_KEY)) p.o_key = 0; p.i_flags = VTI_ISVTI; err = ip_tunnel_ioctl(dev, &p, cmd); if (err) return err; if (cmd != SIOCDELTUNNEL) { p.i_flags |= GRE_KEY; p.o_flags |= GRE_KEY; } if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p))) return -EFAULT; return 0; }

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dmitry popovdmitry popov3517.68%125.00%
steffen klassertsteffen klassert52.53%125.00%
Total198100.00%4100.00%

static const struct net_device_ops vti_netdev_ops = { .ndo_init = vti_tunnel_init, .ndo_uninit = ip_tunnel_uninit, .ndo_start_xmit = vti_tunnel_xmit, .ndo_do_ioctl = vti_tunnel_ioctl, .ndo_change_mtu = ip_tunnel_change_mtu, .ndo_get_stats64 = ip_tunnel_get_stats64, .ndo_get_iflink = ip_tunnel_get_iflink, };
static void vti_tunnel_setup(struct net_device *dev) { dev->netdev_ops = &vti_netdev_ops; dev->type = ARPHRD_TUNNEL; ip_tunnel_setup(dev, vti_net_id); }

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saurabh mohansaurabh mohan722.58%133.33%
nicolas dichtelnicolas dichtel619.35%133.33%
Total31100.00%3100.00%


static int vti_tunnel_init(struct net_device *dev) { struct ip_tunnel *tunnel = netdev_priv(dev); struct iphdr *iph = &tunnel->parms.iph; memcpy(dev->dev_addr, &iph->saddr, 4); memcpy(dev->broadcast, &iph->daddr, 4); dev->hard_header_len = LL_MAX_HEADER + sizeof(struct iphdr); dev->mtu = ETH_DATA_LEN; dev->flags = IFF_NOARP; dev->addr_len = 4; dev->features |= NETIF_F_LLTX; netif_keep_dst(dev); return ip_tunnel_init(dev); }

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saurabh mohansaurabh mohan7064.81%133.33%
americo wangamerico wang3532.41%133.33%
eric dumazeteric dumazet32.78%133.33%
Total108100.00%3100.00%


static void __net_init vti_fb_tunnel_init(struct net_device *dev) { struct ip_tunnel *tunnel = netdev_priv(dev); struct iphdr *iph = &tunnel->parms.iph; iph->version = 4; iph->protocol = IPPROTO_IPIP; iph->ihl = 5; }

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americo wangamerico wang3465.38%150.00%
saurabh mohansaurabh mohan1834.62%150.00%
Total52100.00%2100.00%

static struct xfrm4_protocol vti_esp4_protocol __read_mostly = { .handler = vti_rcv, .input_handler = vti_input, .cb_handler = vti_rcv_cb, .err_handler = vti4_err, .priority = 100, }; static struct xfrm4_protocol vti_ah4_protocol __read_mostly = { .handler = vti_rcv, .input_handler = vti_input, .cb_handler = vti_rcv_cb, .err_handler = vti4_err, .priority = 100, }; static struct xfrm4_protocol vti_ipcomp4_protocol __read_mostly = { .handler = vti_rcv, .input_handler = vti_input, .cb_handler = vti_rcv_cb, .err_handler = vti4_err, .priority = 100, };
static int __net_init vti_init_net(struct net *net) { int err; struct ip_tunnel_net *itn; err = ip_tunnel_init_net(net, vti_net_id, &vti_link_ops, "ip_vti0"); if (err) return err; itn = net_generic(net, vti_net_id); vti_fb_tunnel_init(itn->fb_tunnel_dev); return 0; }

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saurabh mohansaurabh mohan4371.67%150.00%
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Total60100.00%2100.00%


static void __net_exit vti_exit_net(struct net *net) { struct ip_tunnel_net *itn = net_generic(net, vti_net_id); ip_tunnel_delete_net(itn, &vti_link_ops); }

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saurabh mohansaurabh mohan2578.12%133.33%
americo wangamerico wang412.50%133.33%
nicolas dichtelnicolas dichtel39.38%133.33%
Total32100.00%3100.00%

static struct pernet_operations vti_net_ops = { .init = vti_init_net, .exit = vti_exit_net, .id = &vti_net_id, .size = sizeof(struct ip_tunnel_net), };
static int vti_tunnel_validate(struct nlattr *tb[], struct nlattr *data[]) { return 0; }

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saurabh mohansaurabh mohan21100.00%1100.00%
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static void vti_netlink_parms(struct nlattr *data[], struct ip_tunnel_parm *parms) { memset(parms, 0, sizeof(*parms)); parms->iph.protocol = IPPROTO_IPIP; if (!data) return; parms->i_flags = VTI_ISVTI; if (data[IFLA_VTI_LINK]) parms->link = nla_get_u32(data[IFLA_VTI_LINK]); if (data[IFLA_VTI_IKEY]) parms->i_key = nla_get_be32(data[IFLA_VTI_IKEY]); if (data[IFLA_VTI_OKEY]) parms->o_key = nla_get_be32(data[IFLA_VTI_OKEY]); if (data[IFLA_VTI_LOCAL]) parms->iph.saddr = nla_get_in_addr(data[IFLA_VTI_LOCAL]); if (data[IFLA_VTI_REMOTE]) parms->iph.daddr = nla_get_in_addr(data[IFLA_VTI_REMOTE]); }

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saurabh mohansaurabh mohan14194.63%133.33%
steffen klassertsteffen klassert64.03%133.33%
jiri bencjiri benc21.34%133.33%
Total149100.00%3100.00%


static int vti_newlink(struct net *src_net, struct net_device *dev, struct nlattr *tb[], struct nlattr *data[]) { struct ip_tunnel_parm parms; vti_netlink_parms(data, &parms); return ip_tunnel_newlink(dev, tb, &parms); }

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saurabh mohansaurabh mohan3568.63%150.00%
americo wangamerico wang1631.37%150.00%
Total51100.00%2100.00%


static int vti_changelink(struct net_device *dev, struct nlattr *tb[], struct nlattr *data[]) { struct ip_tunnel_parm p; vti_netlink_parms(data, &p); return ip_tunnel_changelink(dev, tb, &p); }

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saurabh mohansaurabh mohan4495.65%150.00%
americo wangamerico wang24.35%150.00%
Total46100.00%2100.00%


static size_t vti_get_size(const struct net_device *dev) { return /* IFLA_VTI_LINK */ nla_total_size(4) + /* IFLA_VTI_IKEY */ nla_total_size(4) + /* IFLA_VTI_OKEY */ nla_total_size(4) + /* IFLA_VTI_LOCAL */ nla_total_size(4) + /* IFLA_VTI_REMOTE */ nla_total_size(4) + 0; }

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saurabh mohansaurabh mohan45100.00%1100.00%
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static int vti_fill_info(struct sk_buff *skb, const struct net_device *dev) { struct ip_tunnel *t = netdev_priv(dev); struct ip_tunnel_parm *p = &t->parms; nla_put_u32(skb, IFLA_VTI_LINK, p->link); nla_put_be32(skb, IFLA_VTI_IKEY, p->i_key); nla_put_be32(skb, IFLA_VTI_OKEY, p->o_key); nla_put_in_addr(skb, IFLA_VTI_LOCAL, p->iph.saddr); nla_put_in_addr(skb, IFLA_VTI_REMOTE, p->iph.daddr); return 0; }

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saurabh mohansaurabh mohan9797.98%150.00%
jiri bencjiri benc22.02%150.00%
Total99100.00%2100.00%

static const struct nla_policy vti_policy[IFLA_VTI_MAX + 1] = { [IFLA_VTI_LINK] = { .type = NLA_U32 }, [IFLA_VTI_IKEY] = { .type = NLA_U32 }, [IFLA_VTI_OKEY] = { .type = NLA_U32 }, [IFLA_VTI_LOCAL] = { .len = FIELD_SIZEOF(struct iphdr, saddr) }, [IFLA_VTI_REMOTE] = { .len = FIELD_SIZEOF(struct iphdr, daddr) }, }; static struct rtnl_link_ops vti_link_ops __read_mostly = { .kind = "vti", .maxtype = IFLA_VTI_MAX, .policy = vti_policy, .priv_size = sizeof(struct ip_tunnel), .setup = vti_tunnel_setup, .validate = vti_tunnel_validate, .newlink = vti_newlink, .changelink = vti_changelink, .dellink = ip_tunnel_dellink, .get_size = vti_get_size, .fill_info = vti_fill_info, .get_link_net = ip_tunnel_get_link_net, };
static bool is_vti_tunnel(const struct net_device *dev) { return dev->netdev_ops == &vti_netdev_ops; }

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static int vti_device_event(struct notifier_block *unused, unsigned long event, void *ptr) { struct net_device *dev = netdev_notifier_info_to_dev(ptr); struct ip_tunnel *tunnel = netdev_priv(dev