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 <david.lebrun@uclouvain.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
David Lebrun 2016-11-08 14:57:40 +01:00 committed by David S. Miller
parent 1ababeba4a
commit 915d7e5e59
7 changed files with 278 additions and 2 deletions

View File

@ -0,0 +1,6 @@
#ifndef _LINUX_SEG6_GENL_H
#define _LINUX_SEG6_GENL_H
#include <uapi/linux/seg6_genl.h>
#endif

View File

@ -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)

View File

@ -14,6 +14,9 @@
#ifndef _NET_SEG6_H
#define _NET_SEG6_H
#include <linux/net.h>
#include <linux/ipv6.h>
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

View File

@ -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

View File

@ -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

View File

@ -61,6 +61,7 @@
#include <net/ip6_tunnel.h>
#endif
#include <net/calipso.h>
#include <net/seg6.h>
#include <asm/uaccess.h>
#include <linux/mroute6.h>
@ -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:

214
net/ipv6/seg6.c Normal file
View File

@ -0,0 +1,214 @@
/*
* SR-IPv6 implementation
*
* Author:
* David Lebrun <david.lebrun@uclouvain.be>
*
*
* 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 <linux/errno.h>
#include <linux/types.h>
#include <linux/socket.h>
#include <linux/net.h>
#include <linux/in6.h>
#include <linux/slab.h>
#include <net/ipv6.h>
#include <net/protocol.h>
#include <net/seg6.h>
#include <net/genetlink.h>
#include <linux/seg6.h>
#include <linux/seg6_genl.h>
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);
}