linux/include/net/seg6.h
David Lebrun bf355b8d2c ipv6: sr: add core files for SR HMAC support
This patch adds the necessary functions to compute and check the HMAC signature
of an SR-enabled packet. Two HMAC algorithms are supported: hmac(sha1) and
hmac(sha256).

In order to avoid dynamic memory allocation for each HMAC computation,
a per-cpu ring buffer is allocated for this purpose.

A new per-interface sysctl called seg6_require_hmac is added, allowing a
user-defined policy for processing HMAC-signed SR-enabled packets.
A value of -1 means that the HMAC field will always be ignored.
A value of 0 means that if an HMAC field is present, its validity will
be enforced (the packet is dropped is the signature is incorrect).
Finally, a value of 1 means that any SR-enabled packet that does not
contain an HMAC signature or whose signature is incorrect will be dropped.

Signed-off-by: David Lebrun <david.lebrun@uclouvain.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-09 20:40:06 -05:00

63 lines
1.4 KiB
C

/*
* 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.
*/
#ifndef _NET_SEG6_H
#define _NET_SEG6_H
#include <linux/net.h>
#include <linux/ipv6.h>
#include <net/lwtunnel.h>
#include <linux/seg6.h>
#include <linux/rhashtable.h>
static inline void update_csum_diff4(struct sk_buff *skb, __be32 from,
__be32 to)
{
__be32 diff[] = { ~from, to };
skb->csum = ~csum_partial((char *)diff, sizeof(diff), ~skb->csum);
}
static inline void update_csum_diff16(struct sk_buff *skb, __be32 *from,
__be32 *to)
{
__be32 diff[] = {
~from[0], ~from[1], ~from[2], ~from[3],
to[0], to[1], to[2], to[3],
};
skb->csum = ~csum_partial((char *)diff, sizeof(diff), ~skb->csum);
}
struct seg6_pernet_data {
struct mutex lock;
struct in6_addr __rcu *tun_src;
#ifdef CONFIG_IPV6_SEG6_HMAC
struct rhashtable hmac_infos;
#endif
};
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);
extern int seg6_iptunnel_init(void);
extern void seg6_iptunnel_exit(void);
extern bool seg6_validate_srh(struct ipv6_sr_hdr *srh, int len);
#endif