diff options
Diffstat (limited to 'net/ipv4/geneve_core.c')
| -rw-r--r-- | net/ipv4/geneve_core.c | 447 |
1 files changed, 447 insertions, 0 deletions
diff --git a/net/ipv4/geneve_core.c b/net/ipv4/geneve_core.c new file mode 100644 index 000000000000..001843d41135 --- /dev/null +++ b/net/ipv4/geneve_core.c @@ -0,0 +1,447 @@ +/* + * Geneve: Generic Network Virtualization Encapsulation + * + * Copyright (c) 2014 Nicira, Inc. + * + * 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. + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/kernel.h> +#include <linux/types.h> +#include <linux/module.h> +#include <linux/errno.h> +#include <linux/slab.h> +#include <linux/skbuff.h> +#include <linux/list.h> +#include <linux/netdevice.h> +#include <linux/in.h> +#include <linux/ip.h> +#include <linux/udp.h> +#include <linux/igmp.h> +#include <linux/etherdevice.h> +#include <linux/if_ether.h> +#include <linux/if_vlan.h> +#include <linux/ethtool.h> +#include <linux/mutex.h> +#include <net/arp.h> +#include <net/ndisc.h> +#include <net/ip.h> +#include <net/ip_tunnels.h> +#include <net/icmp.h> +#include <net/udp.h> +#include <net/rtnetlink.h> +#include <net/route.h> +#include <net/dsfield.h> +#include <net/inet_ecn.h> +#include <net/net_namespace.h> +#include <net/netns/generic.h> +#include <net/geneve.h> +#include <net/protocol.h> +#include <net/udp_tunnel.h> +#if IS_ENABLED(CONFIG_IPV6) +#include <net/ipv6.h> +#include <net/addrconf.h> +#include <net/ip6_tunnel.h> +#include <net/ip6_checksum.h> +#endif + +/* Protects sock_list and refcounts. */ +static DEFINE_MUTEX(geneve_mutex); + +/* per-network namespace private data for this module */ +struct geneve_net { + struct list_head sock_list; +}; + +static int geneve_net_id; + +static struct geneve_sock *geneve_find_sock(struct net *net, + sa_family_t family, __be16 port) +{ + struct geneve_net *gn = net_generic(net, geneve_net_id); + struct geneve_sock *gs; + + list_for_each_entry(gs, &gn->sock_list, list) { + if (inet_sk(gs->sock->sk)->inet_sport == port && + inet_sk(gs->sock->sk)->sk.sk_family == family) + return gs; + } + + return NULL; +} + +static void geneve_build_header(struct genevehdr *geneveh, + __be16 tun_flags, u8 vni[3], + u8 options_len, u8 *options) +{ + geneveh->ver = GENEVE_VER; + geneveh->opt_len = options_len / 4; + geneveh->oam = !!(tun_flags & TUNNEL_OAM); + geneveh->critical = !!(tun_flags & TUNNEL_CRIT_OPT); + geneveh->rsvd1 = 0; + memcpy(geneveh->vni, vni, 3); + geneveh->proto_type = htons(ETH_P_TEB); + geneveh->rsvd2 = 0; + + memcpy(geneveh->options, options, options_len); +} + +/* Transmit a fully formatted Geneve frame. + * + * When calling this function. The skb->data should point + * to the geneve header which is fully formed. + * + * This function will add other UDP tunnel headers. + */ +int geneve_xmit_skb(struct geneve_sock *gs, struct rtable *rt, + struct sk_buff *skb, __be32 src, __be32 dst, __u8 tos, + __u8 ttl, __be16 df, __be16 src_port, __be16 dst_port, + __be16 tun_flags, u8 vni[3], u8 opt_len, u8 *opt, + bool csum, bool xnet) +{ + struct genevehdr *gnvh; + int min_headroom; + int err; + + min_headroom = LL_RESERVED_SPACE(rt->dst.dev) + rt->dst.header_len + + GENEVE_BASE_HLEN + opt_len + sizeof(struct iphdr) + + (skb_vlan_tag_present(skb) ? VLAN_HLEN : 0); + + err = skb_cow_head(skb, min_headroom); + if (unlikely(err)) { + kfree_skb(skb); + return err; + } + + skb = vlan_hwaccel_push_inside(skb); + if (unlikely(!skb)) + return -ENOMEM; + + skb = udp_tunnel_handle_offloads(skb, csum); + if (IS_ERR(skb)) + return PTR_ERR(skb); + + gnvh = (struct genevehdr *)__skb_push(skb, sizeof(*gnvh) + opt_len); + geneve_build_header(gnvh, tun_flags, vni, opt_len, opt); + + skb_set_inner_protocol(skb, htons(ETH_P_TEB)); + + return udp_tunnel_xmit_skb(rt, gs->sock->sk, skb, src, dst, + tos, ttl, df, src_port, dst_port, xnet, + !csum); +} +EXPORT_SYMBOL_GPL(geneve_xmit_skb); + +static int geneve_hlen(struct genevehdr *gh) +{ + return sizeof(*gh) + gh->opt_len * 4; +} + +static struct sk_buff **geneve_gro_receive(struct sk_buff **head, + struct sk_buff *skb, + struct udp_offload *uoff) +{ + struct sk_buff *p, **pp = NULL; + struct genevehdr *gh, *gh2; + unsigned int hlen, gh_len, off_gnv; + const struct packet_offload *ptype; + __be16 type; + int flush = 1; + + off_gnv = skb_gro_offset(skb); + hlen = off_gnv + sizeof(*gh); + gh = skb_gro_header_fast(skb, off_gnv); + if (skb_gro_header_hard(skb, hlen)) { + gh = skb_gro_header_slow(skb, hlen, off_gnv); + if (unlikely(!gh)) + goto out; + } + + if (gh->ver != GENEVE_VER || gh->oam) + goto out; + gh_len = geneve_hlen(gh); + + hlen = off_gnv + gh_len; + if (skb_gro_header_hard(skb, hlen)) { + gh = skb_gro_header_slow(skb, hlen, off_gnv); + if (unlikely(!gh)) + goto out; + } + + flush = 0; + + for (p = *head; p; p = p->next) { + if (!NAPI_GRO_CB(p)->same_flow) + continue; + + gh2 = (struct genevehdr *)(p->data + off_gnv); + if (gh->opt_len != gh2->opt_len || + memcmp(gh, gh2, gh_len)) { + NAPI_GRO_CB(p)->same_flow = 0; + continue; + } + } + + type = gh->proto_type; + + rcu_read_lock(); + ptype = gro_find_receive_by_type(type); + if (!ptype) { + flush = 1; + goto out_unlock; + } + + skb_gro_pull(skb, gh_len); + skb_gro_postpull_rcsum(skb, gh, gh_len); + pp = ptype->callbacks.gro_receive(head, skb); + +out_unlock: + rcu_read_unlock(); +out: + NAPI_GRO_CB(skb)->flush |= flush; + + return pp; +} + +static int geneve_gro_complete(struct sk_buff *skb, int nhoff, + struct udp_offload *uoff) +{ + struct genevehdr *gh; + struct packet_offload *ptype; + __be16 type; + int gh_len; + int err = -ENOSYS; + + udp_tunnel_gro_complete(skb, nhoff); + + gh = (struct genevehdr *)(skb->data + nhoff); + gh_len = geneve_hlen(gh); + type = gh->proto_type; + + rcu_read_lock(); + ptype = gro_find_complete_by_type(type); + if (ptype) + err = ptype->callbacks.gro_complete(skb, nhoff + gh_len); + + rcu_read_unlock(); + return err; +} + +static void geneve_notify_add_rx_port(struct geneve_sock *gs) +{ + struct sock *sk = gs->sock->sk; + sa_family_t sa_family = sk->sk_family; + int err; + + if (sa_family == AF_INET) { + err = udp_add_offload(&gs->udp_offloads); + if (err) + pr_warn("geneve: udp_add_offload failed with status %d\n", + err); + } +} + +static void geneve_notify_del_rx_port(struct geneve_sock *gs) +{ + struct sock *sk = gs->sock->sk; + sa_family_t sa_family = sk->sk_family; + + if (sa_family == AF_INET) + udp_del_offload(&gs->udp_offloads); +} + +/* Callback from net/ipv4/udp.c to receive packets */ +static int geneve_udp_encap_recv(struct sock *sk, struct sk_buff *skb) +{ + struct genevehdr *geneveh; + struct geneve_sock *gs; + int opts_len; + + /* Need Geneve and inner Ethernet header to be present */ + if (unlikely(!pskb_may_pull(skb, GENEVE_BASE_HLEN))) + goto error; + + /* Return packets with reserved bits set */ + geneveh = geneve_hdr(skb); + + if (unlikely(geneveh->ver != GENEVE_VER)) + goto error; + + if (unlikely(geneveh->proto_type != htons(ETH_P_TEB))) + goto error; + + opts_len = geneveh->opt_len * 4; + if (iptunnel_pull_header(skb, GENEVE_BASE_HLEN + opts_len, + htons(ETH_P_TEB))) + goto drop; + + gs = rcu_dereference_sk_user_data(sk); + if (!gs) + goto drop; + + gs->rcv(gs, skb); + return 0; + +drop: + /* Consume bad packet */ + kfree_skb(skb); + return 0; + +error: + /* Let the UDP layer deal with the skb */ + return 1; +} + +static struct socket *geneve_create_sock(struct net *net, bool ipv6, + __be16 port) +{ + struct socket *sock; + struct udp_port_cfg udp_conf; + int err; + + memset(&udp_conf, 0, sizeof(udp_conf)); + + if (ipv6) { + udp_conf.family = AF_INET6; + } else { + udp_conf.family = AF_INET; + udp_conf.local_ip.s_addr = htonl(INADDR_ANY); + } + + udp_conf.local_udp_port = port; + + /* Open UDP socket */ + err = udp_sock_create(net, &udp_conf, &sock); + if (err < 0) + return ERR_PTR(err); + + return sock; +} + +/* Create new listen socket if needed */ +static struct geneve_sock *geneve_socket_create(struct net *net, __be16 port, + geneve_rcv_t *rcv, void *data, + bool ipv6) +{ + struct geneve_net *gn = net_generic(net, geneve_net_id); + struct geneve_sock *gs; + struct socket *sock; + struct udp_tunnel_sock_cfg tunnel_cfg; + + gs = kzalloc(sizeof(*gs), GFP_KERNEL); + if (!gs) + return ERR_PTR(-ENOMEM); + + sock = geneve_create_sock(net, ipv6, port); + if (IS_ERR(sock)) { + kfree(gs); + return ERR_CAST(sock); + } + + gs->sock = sock; + gs->refcnt = 1; + gs->rcv = rcv; + gs->rcv_data = data; + + /* Initialize the geneve udp offloads structure */ + gs->udp_offloads.port = port; + gs->udp_offloads.callbacks.gro_receive = geneve_gro_receive; + gs->udp_offloads.callbacks.gro_complete = geneve_gro_complete; + geneve_notify_add_rx_port(gs); + + /* Mark socket as an encapsulation socket */ + tunnel_cfg.sk_user_data = gs; + tunnel_cfg.encap_type = 1; + tunnel_cfg.encap_rcv = geneve_udp_encap_recv; + tunnel_cfg.encap_destroy = NULL; + setup_udp_tunnel_sock(net, sock, &tunnel_cfg); + + list_add(&gs->list, &gn->sock_list); + + return gs; +} + +struct geneve_sock *geneve_sock_add(struct net *net, __be16 port, + geneve_rcv_t *rcv, void *data, + bool no_share, bool ipv6) +{ + struct geneve_sock *gs; + + mutex_lock(&geneve_mutex); + + gs = geneve_find_sock(net, ipv6 ? AF_INET6 : AF_INET, port); + if (gs) { + if (!no_share && gs->rcv == rcv) + gs->refcnt++; + else + gs = ERR_PTR(-EBUSY); + } else { + gs = geneve_socket_create(net, port, rcv, data, ipv6); + } + + mutex_unlock(&geneve_mutex); + + return gs; +} +EXPORT_SYMBOL_GPL(geneve_sock_add); + +void geneve_sock_release(struct geneve_sock *gs) +{ + mutex_lock(&geneve_mutex); + + if (--gs->refcnt) + goto unlock; + + list_del(&gs->list); + geneve_notify_del_rx_port(gs); + udp_tunnel_sock_release(gs->sock); + kfree_rcu(gs, rcu); + +unlock: + mutex_unlock(&geneve_mutex); +} +EXPORT_SYMBOL_GPL(geneve_sock_release); + +static __net_init int geneve_init_net(struct net *net) +{ + struct geneve_net *gn = net_generic(net, geneve_net_id); + + INIT_LIST_HEAD(&gn->sock_list); + + return 0; +} + +static struct pernet_operations geneve_net_ops = { + .init = geneve_init_net, + .id = &geneve_net_id, + .size = sizeof(struct geneve_net), +}; + +static int __init geneve_init_module(void) +{ + int rc; + + rc = register_pernet_subsys(&geneve_net_ops); + if (rc) + return rc; + + pr_info("Geneve driver\n"); + + return 0; +} +module_init(geneve_init_module); + +static void __exit geneve_cleanup_module(void) +{ + unregister_pernet_subsys(&geneve_net_ops); +} +module_exit(geneve_cleanup_module); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Jesse Gross <jesse@nicira.com>"); +MODULE_DESCRIPTION("Driver for GENEVE encapsulated traffic"); |