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>
		
			
				
	
	
		
			63 lines
		
	
	
		
			1.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			63 lines
		
	
	
		
			1.7 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_HMAC_H
 | |
| #define _NET_SEG6_HMAC_H
 | |
| 
 | |
| #include <net/flow.h>
 | |
| #include <net/ip6_fib.h>
 | |
| #include <net/sock.h>
 | |
| #include <linux/ip.h>
 | |
| #include <linux/ipv6.h>
 | |
| #include <linux/route.h>
 | |
| #include <net/seg6.h>
 | |
| #include <linux/seg6_hmac.h>
 | |
| #include <linux/rhashtable.h>
 | |
| 
 | |
| #define SEG6_HMAC_MAX_DIGESTSIZE	160
 | |
| #define SEG6_HMAC_RING_SIZE		256
 | |
| 
 | |
| struct seg6_hmac_info {
 | |
| 	struct rhash_head node;
 | |
| 	struct rcu_head rcu;
 | |
| 
 | |
| 	u32 hmackeyid;
 | |
| 	char secret[SEG6_HMAC_SECRET_LEN];
 | |
| 	u8 slen;
 | |
| 	u8 alg_id;
 | |
| };
 | |
| 
 | |
| struct seg6_hmac_algo {
 | |
| 	u8 alg_id;
 | |
| 	char name[64];
 | |
| 	struct crypto_shash * __percpu *tfms;
 | |
| 	struct shash_desc * __percpu *shashs;
 | |
| };
 | |
| 
 | |
| extern int seg6_hmac_compute(struct seg6_hmac_info *hinfo,
 | |
| 			     struct ipv6_sr_hdr *hdr, struct in6_addr *saddr,
 | |
| 			     u8 *output);
 | |
| extern struct seg6_hmac_info *seg6_hmac_info_lookup(struct net *net, u32 key);
 | |
| extern int seg6_hmac_info_add(struct net *net, u32 key,
 | |
| 			      struct seg6_hmac_info *hinfo);
 | |
| extern int seg6_hmac_info_del(struct net *net, u32 key);
 | |
| extern int seg6_push_hmac(struct net *net, struct in6_addr *saddr,
 | |
| 			  struct ipv6_sr_hdr *srh);
 | |
| extern bool seg6_hmac_validate_skb(struct sk_buff *skb);
 | |
| extern int seg6_hmac_init(void);
 | |
| extern void seg6_hmac_exit(void);
 | |
| extern int seg6_hmac_net_init(struct net *net);
 | |
| extern void seg6_hmac_net_exit(struct net *net);
 | |
| 
 | |
| #endif
 |