From 915d7e5e5930b4f01d0971d93b9b25ed17d221aa Mon Sep 17 00:00:00 2001 From: David Lebrun Date: Tue, 8 Nov 2016 14:57:40 +0100 Subject: [PATCH] ipv6: sr: add code base for control plane support of SR-IPv6 This patch adds the necessary hooks and structures to provide support for SR-IPv6 control plane, essentially the Generic Netlink commands that will be used for userspace control over the Segment Routing kernel structures. The genetlink commands provide control over two different structures: tunnel source and HMAC data. The tunnel source is the source address that will be used by default when encapsulating packets into an outer IPv6 header + SRH. If the tunnel source is set to :: then an address of the outgoing interface will be selected as the source. The HMAC commands currently just return ENOTSUPP and will be implemented in a future patch. Signed-off-by: David Lebrun Signed-off-by: David S. Miller --- include/linux/seg6_genl.h | 6 + include/net/netns/ipv6.h | 1 + include/net/seg6.h | 16 +++ include/uapi/linux/seg6_genl.h | 32 +++++ net/ipv6/Makefile | 2 +- net/ipv6/af_inet6.c | 9 +- net/ipv6/seg6.c | 214 +++++++++++++++++++++++++++++++++ 7 files changed, 278 insertions(+), 2 deletions(-) create mode 100644 include/linux/seg6_genl.h create mode 100644 include/uapi/linux/seg6_genl.h create mode 100644 net/ipv6/seg6.c diff --git a/include/linux/seg6_genl.h b/include/linux/seg6_genl.h new file mode 100644 index 000000000000..d6c3fb4f3734 --- /dev/null +++ b/include/linux/seg6_genl.h @@ -0,0 +1,6 @@ +#ifndef _LINUX_SEG6_GENL_H +#define _LINUX_SEG6_GENL_H + +#include + +#endif diff --git a/include/net/netns/ipv6.h b/include/net/netns/ipv6.h index 10d0848f5b8a..de7745e2edcc 100644 --- a/include/net/netns/ipv6.h +++ b/include/net/netns/ipv6.h @@ -85,6 +85,7 @@ struct netns_ipv6 { #endif atomic_t dev_addr_genid; atomic_t fib6_sernum; + struct seg6_pernet_data *seg6_data; }; #if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6) diff --git a/include/net/seg6.h b/include/net/seg6.h index 4dd52a7e95f1..7c7b8ed39661 100644 --- a/include/net/seg6.h +++ b/include/net/seg6.h @@ -14,6 +14,9 @@ #ifndef _NET_SEG6_H #define _NET_SEG6_H +#include +#include + static inline void update_csum_diff4(struct sk_buff *skb, __be32 from, __be32 to) { @@ -33,4 +36,17 @@ static inline void update_csum_diff16(struct sk_buff *skb, __be32 *from, skb->csum = ~csum_partial((char *)diff, sizeof(diff), ~skb->csum); } +struct seg6_pernet_data { + struct mutex lock; + struct in6_addr __rcu *tun_src; +}; + +static inline struct seg6_pernet_data *seg6_pernet(struct net *net) +{ + return net->ipv6.seg6_data; +} + +extern int seg6_init(void); +extern void seg6_exit(void); + #endif diff --git a/include/uapi/linux/seg6_genl.h b/include/uapi/linux/seg6_genl.h new file mode 100644 index 000000000000..fcf1c60d7df3 --- /dev/null +++ b/include/uapi/linux/seg6_genl.h @@ -0,0 +1,32 @@ +#ifndef _UAPI_LINUX_SEG6_GENL_H +#define _UAPI_LINUX_SEG6_GENL_H + +#define SEG6_GENL_NAME "SEG6" +#define SEG6_GENL_VERSION 0x1 + +enum { + SEG6_ATTR_UNSPEC, + SEG6_ATTR_DST, + SEG6_ATTR_DSTLEN, + SEG6_ATTR_HMACKEYID, + SEG6_ATTR_SECRET, + SEG6_ATTR_SECRETLEN, + SEG6_ATTR_ALGID, + SEG6_ATTR_HMACINFO, + __SEG6_ATTR_MAX, +}; + +#define SEG6_ATTR_MAX (__SEG6_ATTR_MAX - 1) + +enum { + SEG6_CMD_UNSPEC, + SEG6_CMD_SETHMAC, + SEG6_CMD_DUMPHMAC, + SEG6_CMD_SET_TUNSRC, + SEG6_CMD_GET_TUNSRC, + __SEG6_CMD_MAX, +}; + +#define SEG6_CMD_MAX (__SEG6_CMD_MAX - 1) + +#endif diff --git a/net/ipv6/Makefile b/net/ipv6/Makefile index c174ccb340a1..c92010d62afc 100644 --- a/net/ipv6/Makefile +++ b/net/ipv6/Makefile @@ -9,7 +9,7 @@ ipv6-objs := af_inet6.o anycast.o ip6_output.o ip6_input.o addrconf.o \ route.o ip6_fib.o ipv6_sockglue.o ndisc.o udp.o udplite.o \ raw.o icmp.o mcast.o reassembly.o tcp_ipv6.o ping.o \ exthdrs.o datagram.o ip6_flowlabel.o inet6_connection_sock.o \ - udp_offload.o + udp_offload.o seg6.o ipv6-offload := ip6_offload.o tcpv6_offload.o exthdrs_offload.o diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c index c86911b63f8a..d424f3a3737a 100644 --- a/net/ipv6/af_inet6.c +++ b/net/ipv6/af_inet6.c @@ -61,6 +61,7 @@ #include #endif #include +#include #include #include @@ -991,6 +992,10 @@ static int __init inet6_init(void) if (err) goto calipso_fail; + err = seg6_init(); + if (err) + goto seg6_fail; + #ifdef CONFIG_SYSCTL err = ipv6_sysctl_register(); if (err) @@ -1001,8 +1006,10 @@ out: #ifdef CONFIG_SYSCTL sysctl_fail: - calipso_exit(); + seg6_exit(); #endif +seg6_fail: + calipso_exit(); calipso_fail: pingv6_exit(); pingv6_fail: diff --git a/net/ipv6/seg6.c b/net/ipv6/seg6.c new file mode 100644 index 000000000000..e246b0ba12ac --- /dev/null +++ b/net/ipv6/seg6.c @@ -0,0 +1,214 @@ +/* + * SR-IPv6 implementation + * + * Author: + * David Lebrun + * + * + * 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. + */ + +#include +#include +#include +#include +#include +#include + +#include +#include + +#include +#include +#include +#include + +static struct genl_family seg6_genl_family; + +static const struct nla_policy seg6_genl_policy[SEG6_ATTR_MAX + 1] = { + [SEG6_ATTR_DST] = { .type = NLA_BINARY, + .len = sizeof(struct in6_addr) }, + [SEG6_ATTR_DSTLEN] = { .type = NLA_S32, }, + [SEG6_ATTR_HMACKEYID] = { .type = NLA_U32, }, + [SEG6_ATTR_SECRET] = { .type = NLA_BINARY, }, + [SEG6_ATTR_SECRETLEN] = { .type = NLA_U8, }, + [SEG6_ATTR_ALGID] = { .type = NLA_U8, }, + [SEG6_ATTR_HMACINFO] = { .type = NLA_NESTED, }, +}; + +static int seg6_genl_sethmac(struct sk_buff *skb, struct genl_info *info) +{ + return -ENOTSUPP; +} + +static int seg6_genl_set_tunsrc(struct sk_buff *skb, struct genl_info *info) +{ + struct net *net = genl_info_net(info); + struct in6_addr *val, *t_old, *t_new; + struct seg6_pernet_data *sdata; + + sdata = seg6_pernet(net); + + if (!info->attrs[SEG6_ATTR_DST]) + return -EINVAL; + + val = nla_data(info->attrs[SEG6_ATTR_DST]); + t_new = kmemdup(val, sizeof(*val), GFP_KERNEL); + + mutex_lock(&sdata->lock); + + t_old = sdata->tun_src; + rcu_assign_pointer(sdata->tun_src, t_new); + + mutex_unlock(&sdata->lock); + + synchronize_net(); + kfree(t_old); + + return 0; +} + +static int seg6_genl_get_tunsrc(struct sk_buff *skb, struct genl_info *info) +{ + struct net *net = genl_info_net(info); + struct in6_addr *tun_src; + struct sk_buff *msg; + void *hdr; + + msg = genlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); + if (!msg) + return -ENOMEM; + + hdr = genlmsg_put(msg, info->snd_portid, info->snd_seq, + &seg6_genl_family, 0, SEG6_CMD_GET_TUNSRC); + if (!hdr) + goto free_msg; + + rcu_read_lock(); + tun_src = rcu_dereference(seg6_pernet(net)->tun_src); + + if (nla_put(msg, SEG6_ATTR_DST, sizeof(struct in6_addr), tun_src)) + goto nla_put_failure; + + rcu_read_unlock(); + + genlmsg_end(msg, hdr); + genlmsg_reply(msg, info); + + return 0; + +nla_put_failure: + rcu_read_unlock(); + genlmsg_cancel(msg, hdr); +free_msg: + nlmsg_free(msg); + return -ENOMEM; +} + +static int seg6_genl_dumphmac(struct sk_buff *skb, struct netlink_callback *cb) +{ + return -ENOTSUPP; +} + +static int __net_init seg6_net_init(struct net *net) +{ + struct seg6_pernet_data *sdata; + + sdata = kzalloc(sizeof(*sdata), GFP_KERNEL); + if (!sdata) + return -ENOMEM; + + mutex_init(&sdata->lock); + + sdata->tun_src = kzalloc(sizeof(*sdata->tun_src), GFP_KERNEL); + if (!sdata->tun_src) { + kfree(sdata); + return -ENOMEM; + } + + net->ipv6.seg6_data = sdata; + + return 0; +} + +static void __net_exit seg6_net_exit(struct net *net) +{ + struct seg6_pernet_data *sdata = seg6_pernet(net); + + kfree(sdata->tun_src); + kfree(sdata); +} + +static struct pernet_operations ip6_segments_ops = { + .init = seg6_net_init, + .exit = seg6_net_exit, +}; + +static const struct genl_ops seg6_genl_ops[] = { + { + .cmd = SEG6_CMD_SETHMAC, + .doit = seg6_genl_sethmac, + .policy = seg6_genl_policy, + .flags = GENL_ADMIN_PERM, + }, + { + .cmd = SEG6_CMD_DUMPHMAC, + .dumpit = seg6_genl_dumphmac, + .policy = seg6_genl_policy, + .flags = GENL_ADMIN_PERM, + }, + { + .cmd = SEG6_CMD_SET_TUNSRC, + .doit = seg6_genl_set_tunsrc, + .policy = seg6_genl_policy, + .flags = GENL_ADMIN_PERM, + }, + { + .cmd = SEG6_CMD_GET_TUNSRC, + .doit = seg6_genl_get_tunsrc, + .policy = seg6_genl_policy, + .flags = GENL_ADMIN_PERM, + }, +}; + +static struct genl_family seg6_genl_family __ro_after_init = { + .hdrsize = 0, + .name = SEG6_GENL_NAME, + .version = SEG6_GENL_VERSION, + .maxattr = SEG6_ATTR_MAX, + .netnsok = true, + .parallel_ops = true, + .ops = seg6_genl_ops, + .n_ops = ARRAY_SIZE(seg6_genl_ops), + .module = THIS_MODULE, +}; + +int __init seg6_init(void) +{ + int err = -ENOMEM; + + err = genl_register_family(&seg6_genl_family); + if (err) + goto out; + + err = register_pernet_subsys(&ip6_segments_ops); + if (err) + goto out_unregister_genl; + + pr_info("Segment Routing with IPv6\n"); + +out: + return err; +out_unregister_genl: + genl_unregister_family(&seg6_genl_family); + goto out; +} + +void seg6_exit(void) +{ + unregister_pernet_subsys(&ip6_segments_ops); + genl_unregister_family(&seg6_genl_family); +} -- 2.20.1