| // SPDX-License-Identifier: GPL-2.0-or-later |
| /* |
| * Linux NET3: GRE over IP protocol decoder. |
| * |
| * Authors: Alexey Kuznetsov (kuznet@ms2.inr.ac.ru) |
| */ |
| |
| #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
| |
| #include <linux/capability.h> |
| #include <linux/module.h> |
| #include <linux/types.h> |
| #include <linux/kernel.h> |
| #include <linux/slab.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/if_vlan.h> |
| #include <linux/init.h> |
| #include <linux/in6.h> |
| #include <linux/inetdevice.h> |
| #include <linux/igmp.h> |
| #include <linux/netfilter_ipv4.h> |
| #include <linux/etherdevice.h> |
| #include <linux/if_ether.h> |
| |
| #include <net/sock.h> |
| #include <net/ip.h> |
| #include <net/icmp.h> |
| #include <net/protocol.h> |
| #include <net/ip_tunnels.h> |
| #include <net/arp.h> |
| #include <net/checksum.h> |
| #include <net/dsfield.h> |
| #include <net/inet_ecn.h> |
| #include <net/xfrm.h> |
| #include <net/net_namespace.h> |
| #include <net/netns/generic.h> |
| #include <net/rtnetlink.h> |
| #include <net/gre.h> |
| #include <net/dst_metadata.h> |
| #include <net/erspan.h> |
| |
| /* |
| Problems & solutions |
| -------------------- |
| |
| 1. The most important issue is detecting local dead loops. |
| They would cause complete host lockup in transmit, which |
| would be "resolved" by stack overflow or, if queueing is enabled, |
| with infinite looping in net_bh. |
| |
| We cannot track such dead loops during route installation, |
| it is infeasible task. The most general solutions would be |
| to keep skb->encapsulation counter (sort of local ttl), |
| and silently drop packet when it expires. It is a good |
| solution, but it supposes maintaining new variable in ALL |
| skb, even if no tunneling is used. |
| |
| Current solution: xmit_recursion breaks dead loops. This is a percpu |
| counter, since when we enter the first ndo_xmit(), cpu migration is |
| forbidden. We force an exit if this counter reaches RECURSION_LIMIT |
| |
| 2. Networking dead loops would not kill routers, but would really |
| kill network. IP hop limit plays role of "t->recursion" in this case, |
| if we copy it from packet being encapsulated to upper header. |
| It is very good solution, but it introduces two problems: |
| |
| - Routing protocols, using packets with ttl=1 (OSPF, RIP2), |
| do not work over tunnels. |
| - traceroute does not work. I planned to relay ICMP from tunnel, |
| so that this problem would be solved and traceroute output |
| would even more informative. This idea appeared to be wrong: |
| only Linux complies to rfc1812 now (yes, guys, Linux is the only |
| true router now :-)), all routers (at least, in neighbourhood of mine) |
| return only 8 bytes of payload. It is the end. |
| |
| Hence, if we want that OSPF worked or traceroute said something reasonable, |
| we should search for another solution. |
| |
| One of them is to parse packet trying to detect inner encapsulation |
| made by our node. It is difficult or even impossible, especially, |
| taking into account fragmentation. TO be short, ttl is not solution at all. |
| |
| Current solution: The solution was UNEXPECTEDLY SIMPLE. |
| We force DF flag on tunnels with preconfigured hop limit, |
| that is ALL. :-) Well, it does not remove the problem completely, |
| but exponential growth of network traffic is changed to linear |
| (branches, that exceed pmtu are pruned) and tunnel mtu |
| rapidly degrades to value <68, where looping stops. |
| Yes, it is not good if there exists a router in the loop, |
| which does not force DF, even when encapsulating packets have DF set. |
| But it is not our problem! Nobody could accuse us, we made |
| all that we could make. Even if it is your gated who injected |
| fatal route to network, even if it were you who configured |
| fatal static route: you are innocent. :-) |
| |
| Alexey Kuznetsov. |
| */ |
| |
| static bool log_ecn_error = true; |
| module_param(log_ecn_error, bool, 0644); |
| MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN"); |
| |
| static struct rtnl_link_ops ipgre_link_ops __read_mostly; |
| static int ipgre_tunnel_init(struct net_device *dev); |
| static void erspan_build_header(struct sk_buff *skb, |
| u32 id, u32 index, |
| bool truncate, bool is_ipv4); |
| |
| static unsigned int ipgre_net_id __read_mostly; |
| static unsigned int gre_tap_net_id __read_mostly; |
| static unsigned int erspan_net_id __read_mostly; |
| |
| static int ipgre_err(struct sk_buff *skb, u32 info, |
| const struct tnl_ptk_info *tpi) |
| { |
| |
| /* All the routers (except for Linux) return only |
| 8 bytes of packet payload. It means, that precise relaying of |
| ICMP in the real Internet is absolutely infeasible. |
| |
| Moreover, Cisco "wise men" put GRE key to the third word |
| in GRE header. It makes impossible maintaining even soft |
| state for keyed GRE tunnels with enabled checksum. Tell |
| them "thank you". |
| |
| Well, I wonder, rfc1812 was written by Cisco employee, |
| what the hell these idiots break standards established |
| by themselves??? |
| */ |
| struct net *net = dev_net(skb->dev); |
| struct ip_tunnel_net *itn; |
| const struct iphdr *iph; |
| const int type = icmp_hdr(skb)->type; |
| const int code = icmp_hdr(skb)->code; |
| unsigned int data_len = 0; |
| struct ip_tunnel *t; |
| |
| if (tpi->proto == htons(ETH_P_TEB)) |
| itn = net_generic(net, gre_tap_net_id); |
| else if (tpi->proto == htons(ETH_P_ERSPAN) || |
| tpi->proto == htons(ETH_P_ERSPAN2)) |
| itn = net_generic(net, erspan_net_id); |
| else |
| itn = net_generic(net, ipgre_net_id); |
| |
| iph = (const struct iphdr *)(icmp_hdr(skb) + 1); |
| t = ip_tunnel_lookup(itn, skb->dev->ifindex, tpi->flags, |
| iph->daddr, iph->saddr, tpi->key); |
| |
| if (!t) |
| return -ENOENT; |
| |
| switch (type) { |
| default: |
| case ICMP_PARAMETERPROB: |
| return 0; |
| |
| case ICMP_DEST_UNREACH: |
| switch (code) { |
| case ICMP_SR_FAILED: |
| case ICMP_PORT_UNREACH: |
| /* Impossible event. */ |
| return 0; |
| default: |
| /* All others are translated to HOST_UNREACH. |
| rfc2003 contains "deep thoughts" about NET_UNREACH, |
| I believe they are just ether pollution. --ANK |
| */ |
| break; |
| } |
| break; |
| |
| case ICMP_TIME_EXCEEDED: |
| if (code != ICMP_EXC_TTL) |
| return 0; |
| data_len = icmp_hdr(skb)->un.reserved[1] * 4; /* RFC 4884 4.1 */ |
| break; |
| |
| case ICMP_REDIRECT: |
| break; |
| } |
| |
| #if IS_ENABLED(CONFIG_IPV6) |
| if (tpi->proto == htons(ETH_P_IPV6) && |
| !ip6_err_gen_icmpv6_unreach(skb, iph->ihl * 4 + tpi->hdr_len, |
| type, data_len)) |
| return 0; |
| #endif |
| |
| if (t->parms.iph.daddr == 0 || |
| ipv4_is_multicast(t->parms.iph.daddr)) |
| return 0; |
| |
| if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED) |
| return 0; |
| |
| if (time_before(jiffies, t->err_time + IPTUNNEL_ERR_TIMEO)) |
| t->err_count++; |
| else |
| t->err_count = 1; |
| t->err_time = jiffies; |
| |
| return 0; |
| } |
| |
| static void gre_err(struct sk_buff *skb, u32 info) |
| { |
| /* All the routers (except for Linux) return only |
| * 8 bytes of packet payload. It means, that precise relaying of |
| * ICMP in the real Internet is absolutely infeasible. |
| * |
| * Moreover, Cisco "wise men" put GRE key to the third word |
| * in GRE header. It makes impossible maintaining even soft |
| * state for keyed |
| * GRE tunnels with enabled checksum. Tell them "thank you". |
| * |
| * Well, I wonder, rfc1812 was written by Cisco employee, |
| * what the hell these idiots break standards established |
| * by themselves??? |
| */ |
| |
| const struct iphdr *iph = (struct iphdr *)skb->data; |
| const int type = icmp_hdr(skb)->type; |
| const int code = icmp_hdr(skb)->code; |
| struct tnl_ptk_info tpi; |
| |
| if (gre_parse_header(skb, &tpi, NULL, htons(ETH_P_IP), |
| iph->ihl * 4) < 0) |
| return; |
| |
| if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED) { |
| ipv4_update_pmtu(skb, dev_net(skb->dev), info, |
| skb->dev->ifindex, IPPROTO_GRE); |
| return; |
| } |
| if (type == ICMP_REDIRECT) { |
| ipv4_redirect(skb, dev_net(skb->dev), skb->dev->ifindex, |
| IPPROTO_GRE); |
| return; |
| } |
| |
| ipgre_err(skb, info, &tpi); |
| } |
| |
| static bool is_erspan_type1(int gre_hdr_len) |
| { |
| /* Both ERSPAN type I (version 0) and type II (version 1) use |
| * protocol 0x88BE, but the type I has only 4-byte GRE header, |
| * while type II has 8-byte. |
| */ |
| return gre_hdr_len == 4; |
| } |
| |
| static int erspan_rcv(struct sk_buff *skb, struct tnl_ptk_info *tpi, |
| int gre_hdr_len) |
| { |
| struct net *net = dev_net(skb->dev); |
| struct metadata_dst *tun_dst = NULL; |
| struct erspan_base_hdr *ershdr; |
| struct ip_tunnel_net *itn; |
| struct ip_tunnel *tunnel; |
| const struct iphdr *iph; |
| struct erspan_md2 *md2; |
| int ver; |
| int len; |
| |
| itn = net_generic(net, erspan_net_id); |
| iph = ip_hdr(skb); |
| if (is_erspan_type1(gre_hdr_len)) { |
| ver = 0; |
| tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex, |
| tpi->flags | TUNNEL_NO_KEY, |
| iph->saddr, iph->daddr, 0); |
| } else { |
| if (unlikely(!pskb_may_pull(skb, |
| gre_hdr_len + sizeof(*ershdr)))) |
| return PACKET_REJECT; |
| |
| ershdr = (struct erspan_base_hdr *)(skb->data + gre_hdr_len); |
| ver = ershdr->ver; |
| iph = ip_hdr(skb); |
| tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex, |
| tpi->flags | TUNNEL_KEY, |
| iph->saddr, iph->daddr, tpi->key); |
| } |
| |
| if (tunnel) { |
| if (is_erspan_type1(gre_hdr_len)) |
| len = gre_hdr_len; |
| else |
| len = gre_hdr_len + erspan_hdr_len(ver); |
| |
| if (unlikely(!pskb_may_pull(skb, len))) |
| return PACKET_REJECT; |
| |
| if (__iptunnel_pull_header(skb, |
| len, |
| htons(ETH_P_TEB), |
| false, false) < 0) |
| goto drop; |
| |
| if (tunnel->collect_md) { |
| struct erspan_metadata *pkt_md, *md; |
| struct ip_tunnel_info *info; |
| unsigned char *gh; |
| __be64 tun_id; |
| __be16 flags; |
| |
| tpi->flags |= TUNNEL_KEY; |
| flags = tpi->flags; |
| tun_id = key32_to_tunnel_id(tpi->key); |
| |
| tun_dst = ip_tun_rx_dst(skb, flags, |
| tun_id, sizeof(*md)); |
| if (!tun_dst) |
| return PACKET_REJECT; |
| |
| /* skb can be uncloned in __iptunnel_pull_header, so |
| * old pkt_md is no longer valid and we need to reset |
| * it |
| */ |
| gh = skb_network_header(skb) + |
| skb_network_header_len(skb); |
| pkt_md = (struct erspan_metadata *)(gh + gre_hdr_len + |
| sizeof(*ershdr)); |
| md = ip_tunnel_info_opts(&tun_dst->u.tun_info); |
| md->version = ver; |
| md2 = &md->u.md2; |
| memcpy(md2, pkt_md, ver == 1 ? ERSPAN_V1_MDSIZE : |
| ERSPAN_V2_MDSIZE); |
| |
| info = &tun_dst->u.tun_info; |
| info->key.tun_flags |= TUNNEL_ERSPAN_OPT; |
| info->options_len = sizeof(*md); |
| } |
| |
| skb_reset_mac_header(skb); |
| ip_tunnel_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error); |
| return PACKET_RCVD; |
| } |
| return PACKET_REJECT; |
| |
| drop: |
| kfree_skb(skb); |
| return PACKET_RCVD; |
| } |
| |
| static int __ipgre_rcv(struct sk_buff *skb, const struct tnl_ptk_info *tpi, |
| struct ip_tunnel_net *itn, int hdr_len, bool raw_proto) |
| { |
| struct metadata_dst *tun_dst = NULL; |
| const struct iphdr *iph; |
| struct ip_tunnel *tunnel; |
| |
| iph = ip_hdr(skb); |
| tunnel = ip_tunnel_lookup(itn, skb->dev->ifindex, tpi->flags, |
| iph->saddr, iph->daddr, tpi->key); |
| |
| if (tunnel) { |
| const struct iphdr *tnl_params; |
| |
| if (__iptunnel_pull_header(skb, hdr_len, tpi->proto, |
| raw_proto, false) < 0) |
| goto drop; |
| |
| if (tunnel->dev->type != ARPHRD_NONE) |
| skb_pop_mac_header(skb); |
| else |
| skb_reset_mac_header(skb); |
| |
| tnl_params = &tunnel->parms.iph; |
| if (tunnel->collect_md || tnl_params->daddr == 0) { |
| __be16 flags; |
| __be64 tun_id; |
| |
| flags = tpi->flags & (TUNNEL_CSUM | TUNNEL_KEY); |
| tun_id = key32_to_tunnel_id(tpi->key); |
| tun_dst = ip_tun_rx_dst(skb, flags, tun_id, 0); |
| if (!tun_dst) |
| return PACKET_REJECT; |
| } |
| |
| ip_tunnel_rcv(tunnel, skb, tpi, tun_dst, log_ecn_error); |
| return PACKET_RCVD; |
| } |
| return PACKET_NEXT; |
| |
| drop: |
| kfree_skb(skb); |
| return PACKET_RCVD; |
| } |
| |
| static int ipgre_rcv(struct sk_buff *skb, const struct tnl_ptk_info *tpi, |
| int hdr_len) |
| { |
| struct net *net = dev_net(skb->dev); |
| struct ip_tunnel_net *itn; |
| int res; |
| |
| if (tpi->proto == htons(ETH_P_TEB)) |
| itn = net_generic(net, gre_tap_net_id); |
| else |
| itn = net_generic(net, ipgre_net_id); |
| |
| res = __ipgre_rcv(skb, tpi, itn, hdr_len, false); |
| if (res == PACKET_NEXT && tpi->proto == htons(ETH_P_TEB)) { |
| /* ipgre tunnels in collect metadata mode should receive |
| * also ETH_P_TEB traffic. |
| */ |
| itn = net_generic(net, ipgre_net_id); |
| res = __ipgre_rcv(skb, tpi, itn, hdr_len, true); |
| } |
| return res; |
| } |
| |
| static int gre_rcv(struct sk_buff *skb) |
| { |
| struct tnl_ptk_info tpi; |
| bool csum_err = false; |
| int hdr_len; |
| |
| #ifdef CONFIG_NET_IPGRE_BROADCAST |
| if (ipv4_is_multicast(ip_hdr(skb)->daddr)) { |
| /* Looped back packet, drop it! */ |
| if (rt_is_output_route(skb_rtable(skb))) |
| goto drop; |
| } |
| #endif |
| |
| hdr_len = gre_parse_header(skb, &tpi, &csum_err, htons(ETH_P_IP), 0); |
| if (hdr_len < 0) |
| goto drop; |
| |
| if (unlikely(tpi.proto == htons(ETH_P_ERSPAN) || |
| tpi.proto == htons(ETH_P_ERSPAN2))) { |
| if (erspan_rcv(skb, &tpi, hdr_len) == PACKET_RCVD) |
| return 0; |
| goto out; |
| } |
| |
| if (ipgre_rcv(skb, &tpi, hdr_len) == PACKET_RCVD) |
| return 0; |
| |
| out: |
| icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0); |
| drop: |
| kfree_skb(skb); |
| return 0; |
| } |
| |
| static void __gre_xmit(struct sk_buff *skb, struct net_device *dev, |
| const struct iphdr *tnl_params, |
| __be16 proto) |
| { |
| struct ip_tunnel *tunnel = netdev_priv(dev); |
| __be16 flags = tunnel->parms.o_flags; |
| |
| /* Push GRE header. */ |
| gre_build_header(skb, tunnel->tun_hlen, |
| flags, proto, tunnel->parms.o_key, |
| (flags & TUNNEL_SEQ) ? htonl(atomic_fetch_inc(&tunnel->o_seqno)) : 0); |
| |
| ip_tunnel_xmit(skb, dev, tnl_params, tnl_params->protocol); |
| } |
| |
| static int gre_handle_offloads(struct sk_buff *skb, bool csum) |
| { |
| return iptunnel_handle_offloads(skb, csum ? SKB_GSO_GRE_CSUM : SKB_GSO_GRE); |
| } |
| |
| static void gre_fb_xmit(struct sk_buff *skb, struct net_device *dev, |
| __be16 proto) |
| { |
| struct ip_tunnel *tunnel = netdev_priv(dev); |
| struct ip_tunnel_info *tun_info; |
| const struct ip_tunnel_key *key; |
| int tunnel_hlen; |
| __be16 flags; |
| |
| tun_info = skb_tunnel_info(skb); |
| if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) || |
| ip_tunnel_info_af(tun_info) != AF_INET)) |
| goto err_free_skb; |
| |
| key = &tun_info->key; |
| tunnel_hlen = gre_calc_hlen(key->tun_flags); |
| |
| if (skb_cow_head(skb, dev->needed_headroom)) |
| goto err_free_skb; |
| |
| /* Push Tunnel header. */ |
| if (gre_handle_offloads(skb, !!(tun_info->key.tun_flags & TUNNEL_CSUM))) |
| goto err_free_skb; |
| |
| flags = tun_info->key.tun_flags & |
| (TUNNEL_CSUM | TUNNEL_KEY | TUNNEL_SEQ); |
| gre_build_header(skb, tunnel_hlen, flags, proto, |
| tunnel_id_to_key32(tun_info->key.tun_id), |
| (flags & TUNNEL_SEQ) ? htonl(atomic_fetch_inc(&tunnel->o_seqno)) : 0); |
| |
| ip_md_tunnel_xmit(skb, dev, IPPROTO_GRE, tunnel_hlen); |
| |
| return; |
| |
| err_free_skb: |
| kfree_skb(skb); |
| dev->stats.tx_dropped++; |
| } |
| |
| static void erspan_fb_xmit(struct sk_buff *skb, struct net_device *dev) |
| { |
| struct ip_tunnel *tunnel = netdev_priv(dev); |
| struct ip_tunnel_info *tun_info; |
| const struct ip_tunnel_key *key; |
| struct erspan_metadata *md; |
| bool truncate = false; |
| __be16 proto; |
| int tunnel_hlen; |
| int version; |
| int nhoff; |
| |
| tun_info = skb_tunnel_info(skb); |
| if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) || |
| ip_tunnel_info_af(tun_info) != AF_INET)) |
| goto err_free_skb; |
| |
| key = &tun_info->key; |
| if (!(tun_info->key.tun_flags & TUNNEL_ERSPAN_OPT)) |
| goto err_free_skb; |
| if (tun_info->options_len < sizeof(*md)) |
| goto err_free_skb; |
| md = ip_tunnel_info_opts(tun_info); |
| |
| /* ERSPAN has fixed 8 byte GRE header */ |
| version = md->version; |
| tunnel_hlen = 8 + erspan_hdr_len(version); |
| |
| if (skb_cow_head(skb, dev->needed_headroom)) |
| goto err_free_skb; |
| |
| if (gre_handle_offloads(skb, false)) |
| goto err_free_skb; |
| |
| if (skb->len > dev->mtu + dev->hard_header_len) { |
| pskb_trim(skb, dev->mtu + dev->hard_header_len); |
| truncate = true; |
| } |
| |
| nhoff = skb_network_offset(skb); |
| if (skb->protocol == htons(ETH_P_IP) && |
| (ntohs(ip_hdr(skb)->tot_len) > skb->len - nhoff)) |
| truncate = true; |
| |
| if (skb->protocol == htons(ETH_P_IPV6)) { |
| int thoff; |
| |
| if (skb_transport_header_was_set(skb)) |
| thoff = skb_transport_offset(skb); |
| else |
| thoff = nhoff + sizeof(struct ipv6hdr); |
| if (ntohs(ipv6_hdr(skb)->payload_len) > skb->len - thoff) |
| truncate = true; |
| } |
| |
| if (version == 1) { |
| erspan_build_header(skb, ntohl(tunnel_id_to_key32(key->tun_id)), |
| ntohl(md->u.index), truncate, true); |
| proto = htons(ETH_P_ERSPAN); |
| } else if (version == 2) { |
| erspan_build_header_v2(skb, |
| ntohl(tunnel_id_to_key32(key->tun_id)), |
| md->u.md2.dir, |
| get_hwid(&md->u.md2), |
| truncate, true); |
| proto = htons(ETH_P_ERSPAN2); |
| } else { |
| goto err_free_skb; |
| } |
| |
| gre_build_header(skb, 8, TUNNEL_SEQ, |
| proto, 0, htonl(atomic_fetch_inc(&tunnel->o_seqno))); |
| |
| ip_md_tunnel_xmit(skb, dev, IPPROTO_GRE, tunnel_hlen); |
| |
| return; |
| |
| err_free_skb: |
| kfree_skb(skb); |
| dev->stats.tx_dropped++; |
| } |
| |
| static int gre_fill_metadata_dst(struct net_device *dev, struct sk_buff *skb) |
| { |
| struct ip_tunnel_info *info = skb_tunnel_info(skb); |
| const struct ip_tunnel_key *key; |
| struct rtable *rt; |
| struct flowi4 fl4; |
| |
| if (ip_tunnel_info_af(info) != AF_INET) |
| return -EINVAL; |
| |
| key = &info->key; |
| ip_tunnel_init_flow(&fl4, IPPROTO_GRE, key->u.ipv4.dst, key->u.ipv4.src, |
| tunnel_id_to_key32(key->tun_id), |
| key->tos & ~INET_ECN_MASK, 0, skb->mark, |
| skb_get_hash(skb)); |
| rt = ip_route_output_key(dev_net(dev), &fl4); |
| if (IS_ERR(rt)) |
| return PTR_ERR(rt); |
| |
| ip_rt_put(rt); |
| info->key.u.ipv4.src = fl4.saddr; |
| return 0; |
| } |
| |
| static netdev_tx_t ipgre_xmit(struct sk_buff *skb, |
| struct net_device *dev) |
| { |
| struct ip_tunnel *tunnel = netdev_priv(dev); |
| const struct iphdr *tnl_params; |
| |
| if (!pskb_inet_may_pull(skb)) |
| goto free_skb; |
| |
| if (tunnel->collect_md) { |
| gre_fb_xmit(skb, dev, skb->protocol); |
| return NETDEV_TX_OK; |
| } |
| |
| if (dev->header_ops) { |
| int pull_len = tunnel->hlen + sizeof(struct iphdr); |
| |
| if (skb_cow_head(skb, 0)) |
| goto free_skb; |
| |
| tnl_params = (const struct iphdr *)skb->data; |
| |
| if (!pskb_network_may_pull(skb, pull_len)) |
| goto free_skb; |
| |
| /* ip_tunnel_xmit() needs skb->data pointing to gre header. */ |
| skb_pull(skb, pull_len); |
| skb_reset_mac_header(skb); |
| |
| if (skb->ip_summed == CHECKSUM_PARTIAL && |
| skb_checksum_start(skb) < skb->data) |
| goto free_skb; |
| } else { |
| if (skb_cow_head(skb, dev->needed_headroom)) |
| goto free_skb; |
| |
| tnl_params = &tunnel->parms.iph; |
| } |
| |
| if (gre_handle_offloads(skb, !!(tunnel->parms.o_flags & TUNNEL_CSUM))) |
| goto free_skb; |
| |
| __gre_xmit(skb, dev, tnl_params, skb->protocol); |
| return NETDEV_TX_OK; |
| |
| free_skb: |
| kfree_skb(skb); |
| dev->stats.tx_dropped++; |
| return NETDEV_TX_OK; |
| } |
| |
| static netdev_tx_t erspan_xmit(struct sk_buff *skb, |
| struct net_device *dev) |
| { |
| struct ip_tunnel *tunnel = netdev_priv(dev); |
| bool truncate = false; |
| __be16 proto; |
| |
| if (!pskb_inet_may_pull(skb)) |
| goto free_skb; |
| |
| if (tunnel->collect_md) { |
| erspan_fb_xmit(skb, dev); |
| return NETDEV_TX_OK; |
| } |
| |
| if (gre_handle_offloads(skb, false)) |
| goto free_skb; |
| |
| if (skb_cow_head(skb, dev->needed_headroom)) |
| goto free_skb; |
| |
| if (skb->len > dev->mtu + dev->hard_header_len) { |
| pskb_trim(skb, dev->mtu + dev->hard_header_len); |
| truncate = true; |
| } |
| |
| /* Push ERSPAN header */ |
| if (tunnel->erspan_ver == 0) { |
| proto = htons(ETH_P_ERSPAN); |
| tunnel->parms.o_flags &= ~TUNNEL_SEQ; |
| } else if (tunnel->erspan_ver == 1) { |
| erspan_build_header(skb, ntohl(tunnel->parms.o_key), |
| tunnel->index, |
| truncate, true); |
| proto = htons(ETH_P_ERSPAN); |
| } else if (tunnel->erspan_ver == 2) { |
| erspan_build_header_v2(skb, ntohl(tunnel->parms.o_key), |
| tunnel->dir, tunnel->hwid, |
| truncate, true); |
| proto = htons(ETH_P_ERSPAN2); |
| } else { |
| goto free_skb; |
| } |
| |
| tunnel->parms.o_flags &= ~TUNNEL_KEY; |
| __gre_xmit(skb, dev, &tunnel->parms.iph, proto); |
| return NETDEV_TX_OK; |
| |
| free_skb: |
| kfree_skb(skb); |
| dev->stats.tx_dropped++; |
| return NETDEV_TX_OK; |
| } |
| |
| static netdev_tx_t gre_tap_xmit(struct sk_buff *skb, |
| struct net_device *dev) |
| { |
| struct ip_tunnel *tunnel = netdev_priv(dev); |
| |
| if (!pskb_inet_may_pull(skb)) |
| goto free_skb; |
| |
| if (tunnel->collect_md) { |
| gre_fb_xmit(skb, dev, htons(ETH_P_TEB)); |
| return NETDEV_TX_OK; |
| } |
| |
| if (gre_handle_offloads(skb, !!(tunnel->parms.o_flags & TUNNEL_CSUM))) |
| goto free_skb; |
| |
| if (skb_cow_head(skb, dev->needed_headroom)) |
| goto free_skb; |
| |
| __gre_xmit(skb, dev, &tunnel->parms.iph, htons(ETH_P_TEB)); |
| return NETDEV_TX_OK; |
| |
| free_skb: |
| kfree_skb(skb); |
| dev->stats.tx_dropped++; |
| return NETDEV_TX_OK; |
| } |
| |
| static void ipgre_link_update(struct net_device *dev, bool set_mtu) |
| { |
| struct ip_tunnel *tunnel = netdev_priv(dev); |
| int len; |
| |
| len = tunnel->tun_hlen; |
| tunnel->tun_hlen = gre_calc_hlen(tunnel->parms.o_flags); |
| len = tunnel->tun_hlen - len; |
| tunnel->hlen = tunnel->hlen + len; |
| |
| if (dev->header_ops) |
| dev->hard_header_len += len; |
| else |
| dev->needed_headroom += len; |
| |
| if (set_mtu) |
| dev->mtu = max_t(int, dev->mtu - len, 68); |
| |
| if (!(tunnel->parms.o_flags & TUNNEL_SEQ)) { |
| if (!(tunnel->parms.o_flags & TUNNEL_CSUM) || |
| tunnel->encap.type == TUNNEL_ENCAP_NONE) { |
| dev->features |= NETIF_F_GSO_SOFTWARE; |
| dev->hw_features |= NETIF_F_GSO_SOFTWARE; |
| } else { |
| dev->features &= ~NETIF_F_GSO_SOFTWARE; |
| dev->hw_features &= ~NETIF_F_GSO_SOFTWARE; |
| } |
| dev->features |= NETIF_F_LLTX; |
| } else { |
| dev->hw_features &= ~NETIF_F_GSO_SOFTWARE; |
| dev->features &= ~(NETIF_F_LLTX | NETIF_F_GSO_SOFTWARE); |
| } |
| } |
| |
| static int ipgre_tunnel_ctl(struct net_device *dev, struct ip_tunnel_parm *p, |
| int cmd) |
| { |
| int err; |
| |
| if (cmd == SIOCADDTUNNEL || cmd == SIOCCHGTUNNEL) { |
| if (p->iph.version != 4 || p->iph.protocol != IPPROTO_GRE || |
| p->iph.ihl != 5 || (p->iph.frag_off & htons(~IP_DF)) || |
| ((p->i_flags | p->o_flags) & (GRE_VERSION | GRE_ROUTING))) |
| return -EINVAL; |
| } |
| |
| p->i_flags = gre_flags_to_tnl_flags(p->i_flags); |
| p->o_flags = gre_flags_to_tnl_flags(p->o_flags); |
| |
| err = ip_tunnel_ctl(dev, p, cmd); |
| if (err) |
| return err; |
| |
| if (cmd == SIOCCHGTUNNEL) { |
| struct ip_tunnel *t = netdev_priv(dev); |
| |
| t->parms.i_flags = p->i_flags; |
| t->parms.o_flags = p->o_flags; |
| |
| if (strcmp(dev->rtnl_link_ops->kind, "erspan")) |
| ipgre_link_update(dev, true); |
| } |
| |
| p->i_flags = gre_tnl_flags_to_gre_flags(p->i_flags); |
| p->o_flags = gre_tnl_flags_to_gre_flags(p->o_flags); |
| return 0; |
| } |
| |
| /* Nice toy. Unfortunately, useless in real life :-) |
| It allows to construct virtual multiprotocol broadcast "LAN" |
| over the Internet, provided multicast routing is tuned. |
| |
| |
| I have no idea was this bicycle invented before me, |
| so that I had to set ARPHRD_IPGRE to a random value. |
| I have an impression, that Cisco could make something similar, |
| but this feature is apparently missing in IOS<=11.2(8). |
| |
| I set up 10.66.66/24 and fec0:6666:6666::0/96 as virtual networks |
| with broadcast 224.66.66.66. If you have access to mbone, play with me :-) |
| |
| ping -t 255 224.66.66.66 |
| |
| If nobody answers, mbone does not work. |
| |
| ip tunnel add Universe mode gre remote 224.66.66.66 local <Your_real_addr> ttl 255 |
| ip addr add 10.66.66.<somewhat>/24 dev Universe |
| ifconfig Universe up |
| ifconfig Universe add fe80::<Your_real_addr>/10 |
| ifconfig Universe add fec0:6666:6666::<Your_real_addr>/96 |
| ftp 10.66.66.66 |
| ... |
| ftp fec0:6666:6666::193.233.7.65 |
| ... |
| */ |
| static int ipgre_header(struct sk_buff *skb, struct net_device *dev, |
| unsigned short type, |
| const void *daddr, const void *saddr, unsigned int len) |
| { |
| struct ip_tunnel *t = netdev_priv(dev); |
| struct iphdr *iph; |
| struct gre_base_hdr *greh; |
| |
| iph = skb_push(skb, t->hlen + sizeof(*iph)); |
| greh = (struct gre_base_hdr *)(iph+1); |
| greh->flags = gre_tnl_flags_to_gre_flags(t->parms.o_flags); |
| greh->protocol = htons(type); |
| |
| memcpy(iph, &t->parms.iph, sizeof(struct iphdr)); |
| |
| /* Set the source hardware address. */ |
| if (saddr) |
| memcpy(&iph->saddr, saddr, 4); |
| if (daddr) |
| memcpy(&iph->daddr, daddr, 4); |
| if (iph->daddr) |
| return t->hlen + sizeof(*iph); |
| |
| return -(t->hlen + sizeof(*iph)); |
| } |
| |
| static int ipgre_header_parse(const struct sk_buff *skb, unsigned char *haddr) |
| { |
| const struct iphdr *iph = (const struct iphdr *) skb_mac_header(skb); |
| memcpy(haddr, &iph->saddr, 4); |
| return 4; |
| } |
| |
| static const struct header_ops ipgre_header_ops = { |
| .create = ipgre_header, |
| .parse = ipgre_header_parse, |
| }; |
| |
| #ifdef CONFIG_NET_IPGRE_BROADCAST |
| static int ipgre_open(struct net_device *dev) |
| { |
| struct ip_tunnel *t = netdev_priv(dev); |
| |
| if (ipv4_is_multicast(t->parms.iph.daddr)) { |
| struct flowi4 fl4; |
| struct rtable *rt; |
| |
| rt = ip_route_output_gre(t->net, &fl4, |
| t->parms.iph.daddr, |
| t->parms.iph.saddr, |
| t->parms.o_key, |
| RT_TOS(t->parms.iph.tos), |
| t->parms.link); |
| if (IS_ERR(rt)) |
| return -EADDRNOTAVAIL; |
| dev = rt->dst.dev; |
| ip_rt_put(rt); |
| if (!__in_dev_get_rtnl(dev)) |
| return -EADDRNOTAVAIL; |
| t->mlink = dev->ifindex; |
| ip_mc_inc_group(__in_dev_get_rtnl(dev), t->parms.iph.daddr); |
| } |
| return 0; |
| } |
| |
| static int ipgre_close(struct net_device *dev) |
| { |
| struct ip_tunnel *t = netdev_priv(dev); |
| |
| if (ipv4_is_multicast(t->parms.iph.daddr) && t->mlink) { |
| struct in_device *in_dev; |
| in_dev = inetdev_by_index(t->net, t->mlink); |
| if (in_dev) |
| ip_mc_dec_group(in_dev, t->parms.iph.daddr); |
| } |
| return 0; |
| } |
| #endif |
| |
| static const struct net_device_ops ipgre_netdev_ops = { |
| .ndo_init = ipgre_tunnel_init, |
| .ndo_uninit = ip_tunnel_uninit, |
| #ifdef CONFIG_NET_IPGRE_BROADCAST |
| .ndo_open = ipgre_open, |
| .ndo_stop = ipgre_close, |
| #endif |
| .ndo_start_xmit = ipgre_xmit, |
| .ndo_do_ioctl = ip_tunnel_ioctl, |
| .ndo_change_mtu = ip_tunnel_change_mtu, |
| .ndo_get_stats64 = ip_tunnel_get_stats64, |
| .ndo_get_iflink = ip_tunnel_get_iflink, |
| .ndo_tunnel_ctl = ipgre_tunnel_ctl, |
| }; |
| |
| #define GRE_FEATURES (NETIF_F_SG | \ |
| NETIF_F_FRAGLIST | \ |
| NETIF_F_HIGHDMA | \ |
| NETIF_F_HW_CSUM) |
| |
| static void ipgre_tunnel_setup(struct net_device *dev) |
| { |
| dev->netdev_ops = &ipgre_netdev_ops; |
| dev->type = ARPHRD_IPGRE; |
| ip_tunnel_setup(dev, ipgre_net_id); |
| } |
| |
| static void __gre_tunnel_init(struct net_device *dev) |
| { |
| struct ip_tunnel *tunnel; |
| |
| tunnel = netdev_priv(dev); |
| tunnel->tun_hlen = gre_calc_hlen(tunnel->parms.o_flags); |
| tunnel->parms.iph.protocol = IPPROTO_GRE; |
| |
| tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen; |
| dev->needed_headroom = tunnel->hlen + sizeof(tunnel->parms.iph); |
| |
| dev->features |= GRE_FEATURES; |
| dev->hw_features |= GRE_FEATURES; |
| |
| if (!(tunnel->parms.o_flags & TUNNEL_SEQ)) { |
| /* TCP offload with GRE SEQ is not supported, nor |
| * can we support 2 levels of outer headers requiring |
| * an update. |
| */ |
| if (!(tunnel->parms.o_flags & TUNNEL_CSUM) || |
| (tunnel->encap.type == TUNNEL_ENCAP_NONE)) { |
| dev->features |= NETIF_F_GSO_SOFTWARE; |
| dev->hw_features |= NETIF_F_GSO_SOFTWARE; |
| } |
| |
| /* Can use a lockless transmit, unless we generate |
| * output sequences |
| */ |
| dev->features |= NETIF_F_LLTX; |
| } |
| } |
| |
| static int ipgre_tunnel_init(struct net_device *dev) |
| { |
| struct ip_tunnel *tunnel = netdev_priv(dev); |
| struct iphdr *iph = &tunnel->parms.iph; |
| |
| __gre_tunnel_init(dev); |
| |
| memcpy(dev->dev_addr, &iph->saddr, 4); |
| memcpy(dev->broadcast, &iph->daddr, 4); |
| |
| dev->flags = IFF_NOARP; |
| netif_keep_dst(dev); |
| dev->addr_len = 4; |
| |
| if (iph->daddr && !tunnel->collect_md) { |
| #ifdef CONFIG_NET_IPGRE_BROADCAST |
| if (ipv4_is_multicast(iph->daddr)) { |
| if (!iph->saddr) |
| return -EINVAL; |
| dev->flags = IFF_BROADCAST; |
| dev->header_ops = &ipgre_header_ops; |
| dev->hard_header_len = tunnel->hlen + sizeof(*iph); |
| dev->needed_headroom = 0; |
| } |
| #endif |
| } else if (!tunnel->collect_md) { |
| dev->header_ops = &ipgre_header_ops; |
| dev->hard_header_len = tunnel->hlen + sizeof(*iph); |
| dev->needed_headroom = 0; |
| } |
| |
| return ip_tunnel_init(dev); |
| } |
| |
| static const struct gre_protocol ipgre_protocol = { |
| .handler = gre_rcv, |
| .err_handler = gre_err, |
| }; |
| |
| static int __net_init ipgre_init_net(struct net *net) |
| { |
| return ip_tunnel_init_net(net, ipgre_net_id, &ipgre_link_ops, NULL); |
| } |
| |
| static void __net_exit ipgre_exit_batch_net(struct list_head *list_net) |
| { |
| ip_tunnel_delete_nets(list_net, ipgre_net_id, &ipgre_link_ops); |
| } |
| |
| static struct pernet_operations ipgre_net_ops = { |
| .init = ipgre_init_net, |
| .exit_batch = ipgre_exit_batch_net, |
| .id = &ipgre_net_id, |
| .size = sizeof(struct ip_tunnel_net), |
| }; |
| |
| static int ipgre_tunnel_validate(struct nlattr *tb[], struct nlattr *data[], |
| struct netlink_ext_ack *extack) |
| { |
| __be16 flags; |
| |
| if (!data) |
| return 0; |
| |
| flags = 0; |
| if (data[IFLA_GRE_IFLAGS]) |
| flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]); |
| if (data[IFLA_GRE_OFLAGS]) |
| flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]); |
| if (flags & (GRE_VERSION|GRE_ROUTING)) |
| return -EINVAL; |
| |
| if (data[IFLA_GRE_COLLECT_METADATA] && |
| data[IFLA_GRE_ENCAP_TYPE] && |
| nla_get_u16(data[IFLA_GRE_ENCAP_TYPE]) != TUNNEL_ENCAP_NONE) |
| return -EINVAL; |
| |
| return 0; |
| } |
| |
| static int ipgre_tap_validate(struct nlattr *tb[], struct nlattr *data[], |
| struct netlink_ext_ack *extack) |
| { |
| __be32 daddr; |
| |
| if (tb[IFLA_ADDRESS]) { |
| if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN) |
| return -EINVAL; |
| if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS]))) |
| return -EADDRNOTAVAIL; |
| } |
| |
| if (!data) |
| goto out; |
| |
| if (data[IFLA_GRE_REMOTE]) { |
| memcpy(&daddr, nla_data(data[IFLA_GRE_REMOTE]), 4); |
| if (!daddr) |
| return -EINVAL; |
| } |
| |
| out: |
| return ipgre_tunnel_validate(tb, data, extack); |
| } |
| |
| static int erspan_validate(struct nlattr *tb[], struct nlattr *data[], |
| struct netlink_ext_ack *extack) |
| { |
| __be16 flags = 0; |
| int ret; |
| |
| if (!data) |
| return 0; |
| |
| ret = ipgre_tap_validate(tb, data, extack); |
| if (ret) |
| return ret; |
| |
| if (data[IFLA_GRE_ERSPAN_VER] && |
| nla_get_u8(data[IFLA_GRE_ERSPAN_VER]) == 0) |
| return 0; |
| |
| /* ERSPAN type II/III should only have GRE sequence and key flag */ |
| if (data[IFLA_GRE_OFLAGS]) |
| flags |= nla_get_be16(data[IFLA_GRE_OFLAGS]); |
| if (data[IFLA_GRE_IFLAGS]) |
| flags |= nla_get_be16(data[IFLA_GRE_IFLAGS]); |
| if (!data[IFLA_GRE_COLLECT_METADATA] && |
| flags != (GRE_SEQ | GRE_KEY)) |
| return -EINVAL; |
| |
| /* ERSPAN Session ID only has 10-bit. Since we reuse |
| * 32-bit key field as ID, check it's range. |
| */ |
| if (data[IFLA_GRE_IKEY] && |
| (ntohl(nla_get_be32(data[IFLA_GRE_IKEY])) & ~ID_MASK)) |
| return -EINVAL; |
| |
| if (data[IFLA_GRE_OKEY] && |
| (ntohl(nla_get_be32(data[IFLA_GRE_OKEY])) & ~ID_MASK)) |
| return -EINVAL; |
| |
| return 0; |
| } |
| |
| static int ipgre_netlink_parms(struct net_device *dev, |
| struct nlattr *data[], |
| struct nlattr *tb[], |
| struct ip_tunnel_parm *parms, |
| __u32 *fwmark) |
| { |
| struct ip_tunnel *t = netdev_priv(dev); |
| |
| memset(parms, 0, sizeof(*parms)); |
| |
| parms->iph.protocol = IPPROTO_GRE; |
| |
| if (!data) |
| return 0; |
| |
| if (data[IFLA_GRE_LINK]) |
| parms->link = nla_get_u32(data[IFLA_GRE_LINK]); |
| |
| if (data[IFLA_GRE_IFLAGS]) |
| parms->i_flags = gre_flags_to_tnl_flags(nla_get_be16(data[IFLA_GRE_IFLAGS])); |
| |
| if (data[IFLA_GRE_OFLAGS]) |
| parms->o_flags = gre_flags_to_tnl_flags(nla_get_be16(data[IFLA_GRE_OFLAGS])); |
| |
| if (data[IFLA_GRE_IKEY]) |
| parms->i_key = nla_get_be32(data[IFLA_GRE_IKEY]); |
| |
| if (data[IFLA_GRE_OKEY]) |
| parms->o_key = nla_get_be32(data[IFLA_GRE_OKEY]); |
| |
| if (data[IFLA_GRE_LOCAL]) |
| parms->iph.saddr = nla_get_in_addr(data[IFLA_GRE_LOCAL]); |
| |
| if (data[IFLA_GRE_REMOTE]) |
| parms->iph.daddr = nla_get_in_addr(data[IFLA_GRE_REMOTE]); |
| |
| if (data[IFLA_GRE_TTL]) |
| parms->iph.ttl = nla_get_u8(data[IFLA_GRE_TTL]); |
| |
| if (data[IFLA_GRE_TOS]) |
| parms->iph.tos = nla_get_u8(data[IFLA_GRE_TOS]); |
| |
| if (!data[IFLA_GRE_PMTUDISC] || nla_get_u8(data[IFLA_GRE_PMTUDISC])) { |
| if (t->ignore_df) |
| return -EINVAL; |
| parms->iph.frag_off = htons(IP_DF); |
| } |
| |
| if (data[IFLA_GRE_COLLECT_METADATA]) { |
| t->collect_md = true; |
| if (dev->type == ARPHRD_IPGRE) |
| dev->type = ARPHRD_NONE; |
| } |
| |
| if (data[IFLA_GRE_IGNORE_DF]) { |
| if (nla_get_u8(data[IFLA_GRE_IGNORE_DF]) |
| && (parms->iph.frag_off & htons(IP_DF))) |
| return -EINVAL; |
| t->ignore_df = !!nla_get_u8(data[IFLA_GRE_IGNORE_DF]); |
| } |
| |
| if (data[IFLA_GRE_FWMARK]) |
| *fwmark = nla_get_u32(data[IFLA_GRE_FWMARK]); |
| |
| return 0; |
| } |
| |
| static int erspan_netlink_parms(struct net_device *dev, |
| struct nlattr *data[], |
| struct nlattr *tb[], |
| struct ip_tunnel_parm *parms, |
| __u32 *fwmark) |
| { |
| struct ip_tunnel *t = netdev_priv(dev); |
| int err; |
| |
| err = ipgre_netlink_parms(dev, data, tb, parms, fwmark); |
| if (err) |
| return err; |
| if (!data) |
| return 0; |
| |
| if (data[IFLA_GRE_ERSPAN_VER]) { |
| t->erspan_ver = nla_get_u8(data[IFLA_GRE_ERSPAN_VER]); |
| |
| if (t->erspan_ver > 2) |
| return -EINVAL; |
| } |
| |
| if (t->erspan_ver == 1) { |
| if (data[IFLA_GRE_ERSPAN_INDEX]) { |
| t->index = nla_get_u32(data[IFLA_GRE_ERSPAN_INDEX]); |
| if (t->index & ~INDEX_MASK) |
| return -EINVAL; |
| } |
| } else if (t->erspan_ver == 2) { |
| if (data[IFLA_GRE_ERSPAN_DIR]) { |
| t->dir = nla_get_u8(data[IFLA_GRE_ERSPAN_DIR]); |
| if (t->dir & ~(DIR_MASK >> DIR_OFFSET)) |
| return -EINVAL; |
| } |
| if (data[IFLA_GRE_ERSPAN_HWID]) { |
| t->hwid = nla_get_u16(data[IFLA_GRE_ERSPAN_HWID]); |
| if (t->hwid & ~(HWID_MASK >> HWID_OFFSET)) |
| return -EINVAL; |
| } |
| } |
| |
| return 0; |
| } |
| |
| /* This function returns true when ENCAP attributes are present in the nl msg */ |
| static bool ipgre_netlink_encap_parms(struct nlattr *data[], |
| struct ip_tunnel_encap *ipencap) |
| { |
| bool ret = false; |
| |
| memset(ipencap, 0, sizeof(*ipencap)); |
| |
| if (!data) |
| return ret; |
| |
| if (data[IFLA_GRE_ENCAP_TYPE]) { |
| ret = true; |
| ipencap->type = nla_get_u16(data[IFLA_GRE_ENCAP_TYPE]); |
| } |
| |
| if (data[IFLA_GRE_ENCAP_FLAGS]) { |
| ret = true; |
| ipencap->flags = nla_get_u16(data[IFLA_GRE_ENCAP_FLAGS]); |
| } |
| |
| if (data[IFLA_GRE_ENCAP_SPORT]) { |
| ret = true; |
| ipencap->sport = nla_get_be16(data[IFLA_GRE_ENCAP_SPORT]); |
| } |
| |
| if (data[IFLA_GRE_ENCAP_DPORT]) { |
| ret = true; |
| ipencap->dport = nla_get_be16(data[IFLA_GRE_ENCAP_DPORT]); |
| } |
| |
| return ret; |
| } |
| |
| static int gre_tap_init(struct net_device *dev) |
| { |
| __gre_tunnel_init(dev); |
| dev->priv_flags |= IFF_LIVE_ADDR_CHANGE; |
| netif_keep_dst(dev); |
| |
| return ip_tunnel_init(dev); |
| } |
| |
| static const struct net_device_ops gre_tap_netdev_ops = { |
| .ndo_init = gre_tap_init, |
| .ndo_uninit = ip_tunnel_uninit, |
| .ndo_start_xmit = gre_tap_xmit, |
| .ndo_set_mac_address = eth_mac_addr, |
| .ndo_validate_addr = eth_validate_addr, |
| .ndo_change_mtu = ip_tunnel_change_mtu, |
| .ndo_get_stats64 = ip_tunnel_get_stats64, |
| .ndo_get_iflink = ip_tunnel_get_iflink, |
| .ndo_fill_metadata_dst = gre_fill_metadata_dst, |
| }; |
| |
| static int erspan_tunnel_init(struct net_device *dev) |
| { |
| struct ip_tunnel *tunnel = netdev_priv(dev); |
| |
| if (tunnel->erspan_ver == 0) |
| tunnel->tun_hlen = 4; /* 4-byte GRE hdr. */ |
| else |
| tunnel->tun_hlen = 8; /* 8-byte GRE hdr. */ |
| |
| tunnel->parms.iph.protocol = IPPROTO_GRE; |
| tunnel->hlen = tunnel->tun_hlen + tunnel->encap_hlen + |
| erspan_hdr_len(tunnel->erspan_ver); |
| |
| dev->features |= GRE_FEATURES; |
| dev->hw_features |= GRE_FEATURES; |
| dev->priv_flags |= IFF_LIVE_ADDR_CHANGE; |
| netif_keep_dst(dev); |
| |
| return ip_tunnel_init(dev); |
| } |
| |
| static const struct net_device_ops erspan_netdev_ops = { |
| .ndo_init = erspan_tunnel_init, |
| .ndo_uninit = ip_tunnel_uninit, |
| .ndo_start_xmit = erspan_xmit, |
| .ndo_set_mac_address = eth_mac_addr, |
| .ndo_validate_addr = eth_validate_addr, |
| .ndo_change_mtu = ip_tunnel_change_mtu, |
| .ndo_get_stats64 = ip_tunnel_get_stats64, |
| .ndo_get_iflink = ip_tunnel_get_iflink, |
| .ndo_fill_metadata_dst = gre_fill_metadata_dst, |
| }; |
| |
| static void ipgre_tap_setup(struct net_device *dev) |
| { |
| ether_setup(dev); |
| dev->max_mtu = 0; |
| dev->netdev_ops = &gre_tap_netdev_ops; |
| dev->priv_flags &= ~IFF_TX_SKB_SHARING; |
| dev->priv_flags |= IFF_LIVE_ADDR_CHANGE; |
| ip_tunnel_setup(dev, gre_tap_net_id); |
| } |
| |
| static int |
| ipgre_newlink_encap_setup(struct net_device *dev, struct nlattr *data[]) |
| { |
| struct ip_tunnel_encap ipencap; |
| |
| if (ipgre_netlink_encap_parms(data, &ipencap)) { |
| struct ip_tunnel *t = netdev_priv(dev); |
| int err = ip_tunnel_encap_setup(t, &ipencap); |
| |
| if (err < 0) |
| return err; |
| } |
| |
| return 0; |
| } |
| |
| static int ipgre_newlink(struct net *src_net, struct net_device *dev, |
| struct nlattr *tb[], struct nlattr *data[], |
| struct netlink_ext_ack *extack) |
| { |
| struct ip_tunnel_parm p; |
| __u32 fwmark = 0; |
| int err; |
| |
| err = ipgre_newlink_encap_setup(dev, data); |
| if (err) |
| return err; |
| |
| err = ipgre_netlink_parms(dev, data, tb, &p, &fwmark); |
| if (err < 0) |
| return err; |
| return ip_tunnel_newlink(dev, tb, &p, fwmark); |
| } |
| |
| static int erspan_newlink(struct net *src_net, struct net_device *dev, |
| struct nlattr *tb[], struct nlattr *data[], |
| struct netlink_ext_ack *extack) |
| { |
| struct ip_tunnel_parm p; |
| __u32 fwmark = 0; |
| int err; |
| |
| err = ipgre_newlink_encap_setup(dev, data); |
| if (err) |
| return err; |
| |
| err = erspan_netlink_parms(dev, data, tb, &p, &fwmark); |
| if (err) |
| return err; |
| return ip_tunnel_newlink(dev, tb, &p, fwmark); |
| } |
| |
| static int ipgre_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; |
| int err; |
| |
| err = ipgre_newlink_encap_setup(dev, data); |
| if (err) |
| return err; |
| |
| err = ipgre_netlink_parms(dev, data, tb, &p, &fwmark); |
| if (err < 0) |
| return err; |
| |
| err = ip_tunnel_changelink(dev, tb, &p, fwmark); |
| if (err < 0) |
| return err; |
| |
| t->parms.i_flags = p.i_flags; |
| t->parms.o_flags = p.o_flags; |
| |
| ipgre_link_update(dev, !tb[IFLA_MTU]); |
| |
| return 0; |
| } |
| |
| static int erspan_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; |
| int err; |
| |
| err = ipgre_newlink_encap_setup(dev, data); |
| if (err) |
| return err; |
| |
| err = erspan_netlink_parms(dev, data, tb, &p, &fwmark); |
| if (err < 0) |
| return err; |
| |
| err = ip_tunnel_changelink(dev, tb, &p, fwmark); |
| if (err < 0) |
| return err; |
| |
| t->parms.i_flags = p.i_flags; |
| t->parms.o_flags = p.o_flags; |
| |
| return 0; |
| } |
| |
| static size_t ipgre_get_size(const struct net_device *dev) |
| { |
| return |
| /* IFLA_GRE_LINK */ |
| nla_total_size(4) + |
| /* IFLA_GRE_IFLAGS */ |
| nla_total_size(2) + |
| /* IFLA_GRE_OFLAGS */ |
| nla_total_size(2) + |
| /* IFLA_GRE_IKEY */ |
| nla_total_size(4) + |
| /* IFLA_GRE_OKEY */ |
| nla_total_size(4) + |
| /* IFLA_GRE_LOCAL */ |
| nla_total_size(4) + |
| /* IFLA_GRE_REMOTE */ |
| nla_total_size(4) + |
| /* IFLA_GRE_TTL */ |
| nla_total_size(1) + |
| /* IFLA_GRE_TOS */ |
| nla_total_size(1) + |
| /* IFLA_GRE_PMTUDISC */ |
| nla_total_size(1) + |
| /* IFLA_GRE_ENCAP_TYPE */ |
| nla_total_size(2) + |
| /* IFLA_GRE_ENCAP_FLAGS */ |
| nla_total_size(2) + |
| /* IFLA_GRE_ENCAP_SPORT */ |
| nla_total_size(2) + |
| /* IFLA_GRE_ENCAP_DPORT */ |
| nla_total_size(2) + |
| /* IFLA_GRE_COLLECT_METADATA */ |
| nla_total_size(0) + |
| /* IFLA_GRE_IGNORE_DF */ |
| nla_total_size(1) + |
| /* IFLA_GRE_FWMARK */ |
| nla_total_size(4) + |
| /* IFLA_GRE_ERSPAN_INDEX */ |
| nla_total_size(4) + |
| /* IFLA_GRE_ERSPAN_VER */ |
| nla_total_size(1) + |
| /* IFLA_GRE_ERSPAN_DIR */ |
| nla_total_size(1) + |
| /* IFLA_GRE_ERSPAN_HWID */ |
| nla_total_size(2) + |
| 0; |
| } |
| |
| static int ipgre_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; |
| __be16 o_flags = p->o_flags; |
| |
| if (nla_put_u32(skb, IFLA_GRE_LINK, p->link) || |
| nla_put_be16(skb, IFLA_GRE_IFLAGS, |
| gre_tnl_flags_to_gre_flags(p->i_flags)) || |
| nla_put_be16(skb, IFLA_GRE_OFLAGS, |
| gre_tnl_flags_to_gre_flags(o_flags)) || |
| nla_put_be32(skb, IFLA_GRE_IKEY, p->i_key) || |
| nla_put_be32(skb, IFLA_GRE_OKEY, p->o_key) || |
| nla_put_in_addr(skb, IFLA_GRE_LOCAL, p->iph.saddr) || |
| nla_put_in_addr(skb, IFLA_GRE_REMOTE, p->iph.daddr) || |
| nla_put_u8(skb, IFLA_GRE_TTL, p->iph.ttl) || |
| nla_put_u8(skb, IFLA_GRE_TOS, p->iph.tos) || |
| nla_put_u8(skb, IFLA_GRE_PMTUDISC, |
| !!(p->iph.frag_off & htons(IP_DF))) || |
| nla_put_u32(skb, IFLA_GRE_FWMARK, t->fwmark)) |
| goto nla_put_failure; |
| |
| if (nla_put_u16(skb, IFLA_GRE_ENCAP_TYPE, |
| t->encap.type) || |
| nla_put_be16(skb, IFLA_GRE_ENCAP_SPORT, |
| t->encap.sport) || |
| nla_put_be16(skb, IFLA_GRE_ENCAP_DPORT, |
| t->encap.dport) || |
| nla_put_u16(skb, IFLA_GRE_ENCAP_FLAGS, |
| t->encap.flags)) |
| goto nla_put_failure; |
| |
| if (nla_put_u8(skb, IFLA_GRE_IGNORE_DF, t->ignore_df)) |
| goto nla_put_failure; |
| |
| if (t->collect_md) { |
| if (nla_put_flag(skb, IFLA_GRE_COLLECT_METADATA)) |
| goto nla_put_failure; |
| } |
| |
| return 0; |
| |
| nla_put_failure: |
| return -EMSGSIZE; |
| } |
| |
| static int erspan_fill_info(struct sk_buff *skb, const struct net_device *dev) |
| { |
| struct ip_tunnel *t = netdev_priv(dev); |
| |
| if (t->erspan_ver <= 2) { |
| if (t->erspan_ver != 0 && !t->collect_md) |
| t->parms.o_flags |= TUNNEL_KEY; |
| |
| if (nla_put_u8(skb, IFLA_GRE_ERSPAN_VER, t->erspan_ver)) |
| goto nla_put_failure; |
| |
| if (t->erspan_ver == 1) { |
| if (nla_put_u32(skb, IFLA_GRE_ERSPAN_INDEX, t->index)) |
| goto nla_put_failure; |
| } else if (t->erspan_ver == 2) { |
| if (nla_put_u8(skb, IFLA_GRE_ERSPAN_DIR, t->dir)) |
| goto nla_put_failure; |
| if (nla_put_u16(skb, IFLA_GRE_ERSPAN_HWID, t->hwid)) |
| goto nla_put_failure; |
| } |
| } |
| |
| return ipgre_fill_info(skb, dev); |
| |
| nla_put_failure: |
| return -EMSGSIZE; |
| } |
| |
| static void erspan_setup(struct net_device *dev) |
| { |
| struct ip_tunnel *t = netdev_priv(dev); |
| |
| ether_setup(dev); |
| dev->max_mtu = 0; |
| dev->netdev_ops = &erspan_netdev_ops; |
| dev->priv_flags &= ~IFF_TX_SKB_SHARING; |
| dev->priv_flags |= IFF_LIVE_ADDR_CHANGE; |
| ip_tunnel_setup(dev, erspan_net_id); |
| t->erspan_ver = 1; |
| } |
| |
| static const struct nla_policy ipgre_policy[IFLA_GRE_MAX + 1] = { |
| [IFLA_GRE_LINK] = { .type = NLA_U32 }, |
| [IFLA_GRE_IFLAGS] = { .type = NLA_U16 }, |
| [IFLA_GRE_OFLAGS] = { .type = NLA_U16 }, |
| [IFLA_GRE_IKEY] = { .type = NLA_U32 }, |
| [IFLA_GRE_OKEY] = { .type = NLA_U32 }, |
| [IFLA_GRE_LOCAL] = { .len = sizeof_field(struct iphdr, saddr) }, |
| [IFLA_GRE_REMOTE] = { .len = sizeof_field(struct iphdr, daddr) }, |
| [IFLA_GRE_TTL] = { .type = NLA_U8 }, |
| [IFLA_GRE_TOS] = { .type = NLA_U8 }, |
| [IFLA_GRE_PMTUDISC] = { .type = NLA_U8 }, |
| [IFLA_GRE_ENCAP_TYPE] = { .type = NLA_U16 }, |
| [IFLA_GRE_ENCAP_FLAGS] = { .type = NLA_U16 }, |
| [IFLA_GRE_ENCAP_SPORT] = { .type = NLA_U16 }, |
| [IFLA_GRE_ENCAP_DPORT] = { .type = NLA_U16 }, |
| [IFLA_GRE_COLLECT_METADATA] = { .type = NLA_FLAG }, |
| [IFLA_GRE_IGNORE_DF] = { .type = NLA_U8 }, |
| [IFLA_GRE_FWMARK] = { .type = NLA_U32 }, |
| [IFLA_GRE_ERSPAN_INDEX] = { .type = NLA_U32 }, |
| [IFLA_GRE_ERSPAN_VER] = { .type = NLA_U8 }, |
| [IFLA_GRE_ERSPAN_DIR] = { .type = NLA_U8 }, |
| [IFLA_GRE_ERSPAN_HWID] = { .type = NLA_U16 }, |
| }; |
| |
| static struct rtnl_link_ops ipgre_link_ops __read_mostly = { |
| .kind = "gre", |
| .maxtype = IFLA_GRE_MAX, |
| .policy = ipgre_policy, |
| .priv_size = sizeof(struct ip_tunnel), |
| .setup = ipgre_tunnel_setup, |
| .validate = ipgre_tunnel_validate, |
| .newlink = ipgre_newlink, |
| .changelink = ipgre_changelink, |
| .dellink = ip_tunnel_dellink, |
| .get_size = ipgre_get_size, |
| .fill_info = ipgre_fill_info, |
| .get_link_net = ip_tunnel_get_link_net, |
| }; |
| |
| static struct rtnl_link_ops ipgre_tap_ops __read_mostly = { |
| .kind = "gretap", |
| .maxtype = IFLA_GRE_MAX, |
| .policy = ipgre_policy, |
| .priv_size = sizeof(struct ip_tunnel), |
| .setup = ipgre_tap_setup, |
| .validate = ipgre_tap_validate, |
| .newlink = ipgre_newlink, |
| .changelink = ipgre_changelink, |
| .dellink = ip_tunnel_dellink, |
| .get_size = ipgre_get_size, |
| .fill_info = ipgre_fill_info, |
| .get_link_net = ip_tunnel_get_link_net, |
| }; |
| |
| static struct rtnl_link_ops erspan_link_ops __read_mostly = { |
| .kind = "erspan", |
| .maxtype = IFLA_GRE_MAX, |
| .policy = ipgre_policy, |
| .priv_size = sizeof(struct ip_tunnel), |
| .setup = erspan_setup, |
| .validate = erspan_validate, |
| .newlink = erspan_newlink, |
| .changelink = erspan_changelink, |
| .dellink = ip_tunnel_dellink, |
| .get_size = ipgre_get_size, |
| .fill_info = erspan_fill_info, |
| .get_link_net = ip_tunnel_get_link_net, |
| }; |
| |
| struct net_device *gretap_fb_dev_create(struct net *net, const char *name, |
| u8 name_assign_type) |
| { |
| struct nlattr *tb[IFLA_MAX + 1]; |
| struct net_device *dev; |
| LIST_HEAD(list_kill); |
| struct ip_tunnel *t; |
| int err; |
| |
| memset(&tb, 0, sizeof(tb)); |
| |
| dev = rtnl_create_link(net, name, name_assign_type, |
| &ipgre_tap_ops, tb, NULL); |
| if (IS_ERR(dev)) |
| return dev; |
| |
| /* Configure flow based GRE device. */ |
| t = netdev_priv(dev); |
| t->collect_md = true; |
| |
| err = ipgre_newlink(net, dev, tb, NULL, NULL); |
| if (err < 0) { |
| free_netdev(dev); |
| return ERR_PTR(err); |
| } |
| |
| /* openvswitch users expect packet sizes to be unrestricted, |
| * so set the largest MTU we can. |
| */ |
| err = __ip_tunnel_change_mtu(dev, IP_MAX_MTU, false); |
| if (err) |
| goto out; |
| |
| err = rtnl_configure_link(dev, NULL); |
| if (err < 0) |
| goto out; |
| |
| return dev; |
| out: |
| ip_tunnel_dellink(dev, &list_kill); |
| unregister_netdevice_many(&list_kill); |
| return ERR_PTR(err); |
| } |
| EXPORT_SYMBOL_GPL(gretap_fb_dev_create); |
| |
| static int __net_init ipgre_tap_init_net(struct net *net) |
| { |
| return ip_tunnel_init_net(net, gre_tap_net_id, &ipgre_tap_ops, "gretap0"); |
| } |
| |
| static void __net_exit ipgre_tap_exit_batch_net(struct list_head *list_net) |
| { |
| ip_tunnel_delete_nets(list_net, gre_tap_net_id, &ipgre_tap_ops); |
| } |
| |
| static struct pernet_operations ipgre_tap_net_ops = { |
| .init = ipgre_tap_init_net, |
| .exit_batch = ipgre_tap_exit_batch_net, |
| .id = &gre_tap_net_id, |
| .size = sizeof(struct ip_tunnel_net), |
| }; |
| |
| static int __net_init erspan_init_net(struct net *net) |
| { |
| return ip_tunnel_init_net(net, erspan_net_id, |
| &erspan_link_ops, "erspan0"); |
| } |
| |
| static void __net_exit erspan_exit_batch_net(struct list_head *net_list) |
| { |
| ip_tunnel_delete_nets(net_list, erspan_net_id, &erspan_link_ops); |
| } |
| |
| static struct pernet_operations erspan_net_ops = { |
| .init = erspan_init_net, |
| .exit_batch = erspan_exit_batch_net, |
| .id = &erspan_net_id, |
| .size = sizeof(struct ip_tunnel_net), |
| }; |
| |
| static int __init ipgre_init(void) |
| { |
| int err; |
| |
| pr_info("GRE over IPv4 tunneling driver\n"); |
| |
| err = register_pernet_device(&ipgre_net_ops); |
| if (err < 0) |
| return err; |
| |
| err = register_pernet_device(&ipgre_tap_net_ops); |
| if (err < 0) |
| goto pnet_tap_failed; |
| |
| err = register_pernet_device(&erspan_net_ops); |
| if (err < 0) |
| goto pnet_erspan_failed; |
| |
| err = gre_add_protocol(&ipgre_protocol, GREPROTO_CISCO); |
| if (err < 0) { |
| pr_info("%s: can't add protocol\n", __func__); |
| goto add_proto_failed; |
| } |
| |
| err = rtnl_link_register(&ipgre_link_ops); |
| if (err < 0) |
| goto rtnl_link_failed; |
| |
| err = rtnl_link_register(&ipgre_tap_ops); |
| if (err < 0) |
| goto tap_ops_failed; |
| |
| err = rtnl_link_register(&erspan_link_ops); |
| if (err < 0) |
| goto erspan_link_failed; |
| |
| return 0; |
| |
| erspan_link_failed: |
| rtnl_link_unregister(&ipgre_tap_ops); |
| tap_ops_failed: |
| rtnl_link_unregister(&ipgre_link_ops); |
| rtnl_link_failed: |
| gre_del_protocol(&ipgre_protocol, GREPROTO_CISCO); |
| add_proto_failed: |
| unregister_pernet_device(&erspan_net_ops); |
| pnet_erspan_failed: |
| unregister_pernet_device(&ipgre_tap_net_ops); |
| pnet_tap_failed: |
| unregister_pernet_device(&ipgre_net_ops); |
| return err; |
| } |
| |
| static void __exit ipgre_fini(void) |
| { |
| rtnl_link_unregister(&ipgre_tap_ops); |
| rtnl_link_unregister(&ipgre_link_ops); |
| rtnl_link_unregister(&erspan_link_ops); |
| gre_del_protocol(&ipgre_protocol, GREPROTO_CISCO); |
| unregister_pernet_device(&ipgre_tap_net_ops); |
| unregister_pernet_device(&ipgre_net_ops); |
| unregister_pernet_device(&erspan_net_ops); |
| } |
| |
| module_init(ipgre_init); |
| module_exit(ipgre_fini); |
| MODULE_LICENSE("GPL"); |
| MODULE_ALIAS_RTNL_LINK("gre"); |
| MODULE_ALIAS_RTNL_LINK("gretap"); |
| MODULE_ALIAS_RTNL_LINK("erspan"); |
| MODULE_ALIAS_NETDEV("gre0"); |
| MODULE_ALIAS_NETDEV("gretap0"); |
| MODULE_ALIAS_NETDEV("erspan0"); |