From ace9429bb58fd418f0c81d4c2835699bddf6bde6 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Thu, 11 Apr 2024 10:27:49 +0200 Subject: Adding upstream version 6.6.15. Signed-off-by: Daniel Baumann --- net/ipv4/ip_vti.c | 726 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 726 insertions(+) create mode 100644 net/ipv4/ip_vti.c (limited to 'net/ipv4/ip_vti.c') diff --git a/net/ipv4/ip_vti.c b/net/ipv4/ip_vti.c new file mode 100644 index 0000000000..d1e7d0ceb7 --- /dev/null +++ b/net/ipv4/ip_vti.c @@ -0,0 +1,726 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Linux NET3: IP/IP protocol decoder modified to support + * virtual tunnel interface + * + * Authors: + * Saurabh Mohan (saurabh.mohan@vyatta.com) 05/07/2012 + */ + +/* + 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 +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include +#include +#include +#include +#include +#include + +static struct rtnl_link_ops vti_link_ops __read_mostly; + +static unsigned 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, bool update_skb_dev) +{ + 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; + + if (update_skb_dev) + skb->dev = tunnel->dev; + + return xfrm_input(skb, nexthdr, spi, encap_type); + } + + return -EINVAL; +drop: + kfree_skb(skb); + return 0; +} + +static int vti_input_proto(struct sk_buff *skb, int nexthdr, __be32 spi, + int encap_type) +{ + return vti_input(skb, nexthdr, spi, encap_type, false); +} + +static int vti_rcv(struct sk_buff *skb, __be32 spi, bool update_skb_dev) +{ + 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, spi, 0, update_skb_dev); +} + +static int vti_rcv_proto(struct sk_buff *skb) +{ + return vti_rcv(skb, 0, false); +} + +static int vti_rcv_cb(struct sk_buff *skb, int err) +{ + unsigned short family; + struct net_device *dev; + struct xfrm_state *x; + const 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_INC(dev, rx_errors); + DEV_STATS_INC(dev, 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->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; + dev_sw_netstats_rx_add(dev, skb->len); + + return 0; +} + +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; +} + +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 pkt_len = skb->len; + int err; + int mtu; + + if (!dst) { + switch (skb->protocol) { + case htons(ETH_P_IP): { + struct rtable *rt; + + fl->u.ip4.flowi4_oif = dev->ifindex; + fl->u.ip4.flowi4_flags |= FLOWI_FLAG_ANYSRC; + rt = __ip_route_output_key(dev_net(dev), &fl->u.ip4); + if (IS_ERR(rt)) { + DEV_STATS_INC(dev, tx_carrier_errors); + goto tx_error_icmp; + } + dst = &rt->dst; + skb_dst_set(skb, dst); + break; + } +#if IS_ENABLED(CONFIG_IPV6) + case htons(ETH_P_IPV6): + fl->u.ip6.flowi6_oif = dev->ifindex; + fl->u.ip6.flowi6_flags |= FLOWI_FLAG_ANYSRC; + dst = ip6_route_output(dev_net(dev), NULL, &fl->u.ip6); + if (dst->error) { + dst_release(dst); + dst = NULL; + DEV_STATS_INC(dev, tx_carrier_errors); + goto tx_error_icmp; + } + skb_dst_set(skb, dst); + break; +#endif + default: + DEV_STATS_INC(dev, tx_carrier_errors); + goto tx_error_icmp; + } + } + + dst_hold(dst); + dst = xfrm_lookup_route(tunnel->net, dst, fl, NULL, 0); + if (IS_ERR(dst)) { + DEV_STATS_INC(dev, tx_carrier_errors); + goto tx_error_icmp; + } + + if (dst->flags & DST_XFRM_QUEUE) + goto xmit; + + if (!vti_state_check(dst->xfrm, parms->iph.daddr, parms->iph.saddr)) { + DEV_STATS_INC(dev, tx_carrier_errors); + dst_release(dst); + goto tx_error_icmp; + } + + tdev = dst->dev; + + if (tdev == dev) { + dst_release(dst); + DEV_STATS_INC(dev, collisions); + goto tx_error; + } + + mtu = dst_mtu(dst); + if (skb->len > mtu) { + skb_dst_update_pmtu_no_confirm(skb, mtu); + if (skb->protocol == htons(ETH_P_IP)) { + if (!(ip_hdr(skb)->frag_off & htons(IP_DF))) + goto xmit; + icmp_ndo_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, + htonl(mtu)); + } else { + if (mtu < IPV6_MIN_MTU) + mtu = IPV6_MIN_MTU; + + icmpv6_ndo_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu); + } + + dst_release(dst); + goto tx_error; + } + +xmit: + 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 = pkt_len; + iptunnel_xmit_stats(dev, err); + return NETDEV_TX_OK; + +tx_error_icmp: + dst_link_failure(skb); +tx_error: + DEV_STATS_INC(dev, tx_errors); + kfree_skb(skb); + return NETDEV_TX_OK; +} + +/* 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; + + if (!pskb_inet_may_pull(skb)) + goto tx_err; + + memset(&fl, 0, sizeof(fl)); + + switch (skb->protocol) { + case htons(ETH_P_IP): + memset(IPCB(skb), 0, sizeof(*IPCB(skb))); + xfrm_decode_session(skb, &fl, AF_INET); + break; + case htons(ETH_P_IPV6): + memset(IP6CB(skb), 0, sizeof(*IP6CB(skb))); + xfrm_decode_session(skb, &fl, AF_INET6); + break; + default: + goto tx_err; + } + + /* override mark with tunnel output key */ + fl.flowi_mark = be32_to_cpu(tunnel->parms.o_key); + + return vti_xmit(skb, dev, &fl); + +tx_err: + DEV_STATS_INC(dev, tx_errors); + kfree_skb(skb); + return NETDEV_TX_OK; +} + +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; + break; + 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, protocol); + else + ipv4_redirect(skb, net, 0, protocol); + xfrm_state_put(x); + + return 0; +} + +static int +vti_tunnel_ctl(struct net_device *dev, struct ip_tunnel_parm *p, int cmd) +{ + int err = 0; + + 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_ctl(dev, p, cmd); + if (err) + return err; + + if (cmd != SIOCDELTUNNEL) { + p->i_flags |= GRE_KEY; + p->o_flags |= GRE_KEY; + } + return 0; +} + +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_siocdevprivate = ip_tunnel_siocdevprivate, + .ndo_change_mtu = ip_tunnel_change_mtu, + .ndo_get_stats64 = dev_get_tstats64, + .ndo_get_iflink = ip_tunnel_get_iflink, + .ndo_tunnel_ctl = vti_tunnel_ctl, +}; + +static void vti_tunnel_setup(struct net_device *dev) +{ + dev->netdev_ops = &vti_netdev_ops; + dev->header_ops = &ip_tunnel_header_ops; + dev->type = ARPHRD_TUNNEL; + ip_tunnel_setup(dev, vti_net_id); +} + +static int vti_tunnel_init(struct net_device *dev) +{ + struct ip_tunnel *tunnel = netdev_priv(dev); + struct iphdr *iph = &tunnel->parms.iph; + + __dev_addr_set(dev, &iph->saddr, 4); + memcpy(dev->broadcast, &iph->daddr, 4); + + dev->flags = IFF_NOARP; + dev->addr_len = 4; + dev->features |= NETIF_F_LLTX; + netif_keep_dst(dev); + + return ip_tunnel_init(dev); +} + +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; +} + +static struct xfrm4_protocol vti_esp4_protocol __read_mostly = { + .handler = vti_rcv_proto, + .input_handler = vti_input_proto, + .cb_handler = vti_rcv_cb, + .err_handler = vti4_err, + .priority = 100, +}; + +static struct xfrm4_protocol vti_ah4_protocol __read_mostly = { + .handler = vti_rcv_proto, + .input_handler = vti_input_proto, + .cb_handler = vti_rcv_cb, + .err_handler = vti4_err, + .priority = 100, +}; + +static struct xfrm4_protocol vti_ipcomp4_protocol __read_mostly = { + .handler = vti_rcv_proto, + .input_handler = vti_input_proto, + .cb_handler = vti_rcv_cb, + .err_handler = vti4_err, + .priority = 100, +}; + +#if IS_ENABLED(CONFIG_INET_XFRM_TUNNEL) +static int vti_rcv_tunnel(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, IPPROTO_IPIP, ip_hdr(skb)->saddr, 0, false); +} + +static struct xfrm_tunnel vti_ipip_handler __read_mostly = { + .handler = vti_rcv_tunnel, + .cb_handler = vti_rcv_cb, + .err_handler = vti4_err, + .priority = 0, +}; + +#if IS_ENABLED(CONFIG_IPV6) +static struct xfrm_tunnel vti_ipip6_handler __read_mostly = { + .handler = vti_rcv_tunnel, + .cb_handler = vti_rcv_cb, + .err_handler = vti4_err, + .priority = 0, +}; +#endif +#endif + +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); + if (itn->fb_tunnel_dev) + vti_fb_tunnel_init(itn->fb_tunnel_dev); + return 0; +} + +static void __net_exit vti_exit_batch_net(struct list_head *list_net) +{ + ip_tunnel_delete_nets(list_net, vti_net_id, &vti_link_ops); +} + +static struct pernet_operations vti_net_ops = { + .init = vti_init_net, + .exit_batch = vti_exit_batch_net, + .id = &vti_net_id, + .size = sizeof(struct ip_tunnel_net), +}; + +static int vti_tunnel_validate(struct nlattr *tb[], struct nlattr *data[], + struct netlink_ext_ack *extack) +{ + return 0; +} + +static void vti_netlink_parms(struct nlattr *data[], + struct ip_tunnel_parm *parms, + __u32 *fwmark) +{ + 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]); + + if (data[IFLA_VTI_FWMARK]) + *fwmark = nla_get_u32(data[IFLA_VTI_FWMARK]); +} + +static int vti_newlink(struct net *src_net, struct net_device *dev, + struct nlattr *tb[], struct nlattr *data[], + struct netlink_ext_ack *extack) +{ + struct ip_tunnel_parm parms; + __u32 fwmark = 0; + + vti_netlink_parms(data, &parms, &fwmark); + return ip_tunnel_newlink(dev, tb, &parms, fwmark); +} + +static int vti_changelink(struct net_device *dev, struct nlattr *tb[], + struct nlattr *data[], + struct netlink_ext_ack *extack) +{ + struct ip_tunnel *t = netdev_priv(dev); + __u32 fwmark = t->fwmark; + struct ip_tunnel_parm p; + + vti_netlink_parms(data, &p, &fwmark); + return ip_tunnel_changelink(dev, tb, &p, fwmark); +} + +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) + + /* IFLA_VTI_FWMARK */ + nla_total_size(4) + + 0; +} + +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; + + if (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) || + nla_put_u32(skb, IFLA_VTI_FWMARK, t->fwmark)) + return -EMSGSIZE; + + return 0; +} + +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 = sizeof_field(struct iphdr, saddr) }, + [IFLA_VTI_REMOTE] = { .len = sizeof_field(struct iphdr, daddr) }, + [IFLA_VTI_FWMARK] = { .type = NLA_U32 }, +}; + +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 int __init vti_init(void) +{ + const char *msg; + int err; + + pr_info("IPv4 over IPsec tunneling driver\n"); + + msg = "tunnel device"; + err = register_pernet_device(&vti_net_ops); + if (err < 0) + goto pernet_dev_failed; + + msg = "tunnel protocols"; + err = xfrm4_protocol_register(&vti_esp4_protocol, IPPROTO_ESP); + if (err < 0) + goto xfrm_proto_esp_failed; + err = xfrm4_protocol_register(&vti_ah4_protocol, IPPROTO_AH); + if (err < 0) + goto xfrm_proto_ah_failed; + err = xfrm4_protocol_register(&vti_ipcomp4_protocol, IPPROTO_COMP); + if (err < 0) + goto xfrm_proto_comp_failed; + +#if IS_ENABLED(CONFIG_INET_XFRM_TUNNEL) + msg = "ipip tunnel"; + err = xfrm4_tunnel_register(&vti_ipip_handler, AF_INET); + if (err < 0) + goto xfrm_tunnel_ipip_failed; +#if IS_ENABLED(CONFIG_IPV6) + err = xfrm4_tunnel_register(&vti_ipip6_handler, AF_INET6); + if (err < 0) + goto xfrm_tunnel_ipip6_failed; +#endif +#endif + + msg = "netlink interface"; + err = rtnl_link_register(&vti_link_ops); + if (err < 0) + goto rtnl_link_failed; + + return err; + +rtnl_link_failed: +#if IS_ENABLED(CONFIG_INET_XFRM_TUNNEL) +#if IS_ENABLED(CONFIG_IPV6) + xfrm4_tunnel_deregister(&vti_ipip6_handler, AF_INET6); +xfrm_tunnel_ipip6_failed: +#endif + xfrm4_tunnel_deregister(&vti_ipip_handler, AF_INET); +xfrm_tunnel_ipip_failed: +#endif + xfrm4_protocol_deregister(&vti_ipcomp4_protocol, IPPROTO_COMP); +xfrm_proto_comp_failed: + xfrm4_protocol_deregister(&vti_ah4_protocol, IPPROTO_AH); +xfrm_proto_ah_failed: + xfrm4_protocol_deregister(&vti_esp4_protocol, IPPROTO_ESP); +xfrm_proto_esp_failed: + unregister_pernet_device(&vti_net_ops); +pernet_dev_failed: + pr_err("vti init: failed to register %s\n", msg); + return err; +} + +static void __exit vti_fini(void) +{ + rtnl_link_unregister(&vti_link_ops); +#if IS_ENABLED(CONFIG_INET_XFRM_TUNNEL) +#if IS_ENABLED(CONFIG_IPV6) + xfrm4_tunnel_deregister(&vti_ipip6_handler, AF_INET6); +#endif + xfrm4_tunnel_deregister(&vti_ipip_handler, AF_INET); +#endif + xfrm4_protocol_deregister(&vti_ipcomp4_protocol, IPPROTO_COMP); + xfrm4_protocol_deregister(&vti_ah4_protocol, IPPROTO_AH); + xfrm4_protocol_deregister(&vti_esp4_protocol, IPPROTO_ESP); + unregister_pernet_device(&vti_net_ops); +} + +module_init(vti_init); +module_exit(vti_fini); +MODULE_LICENSE("GPL"); +MODULE_ALIAS_RTNL_LINK("vti"); +MODULE_ALIAS_NETDEV("ip_vti0"); -- cgit v1.2.3