xref: /openbmc/linux/net/xfrm/xfrm_inout.h (revision 63705da3)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #include <linux/ipv6.h>
3 #include <net/dsfield.h>
4 #include <net/xfrm.h>
5 
6 #ifndef XFRM_INOUT_H
7 #define XFRM_INOUT_H 1
8 
9 static inline void xfrm4_extract_header(struct sk_buff *skb)
10 {
11 	const struct iphdr *iph = ip_hdr(skb);
12 
13 	XFRM_MODE_SKB_CB(skb)->ihl = sizeof(*iph);
14 	XFRM_MODE_SKB_CB(skb)->id = iph->id;
15 	XFRM_MODE_SKB_CB(skb)->frag_off = iph->frag_off;
16 	XFRM_MODE_SKB_CB(skb)->tos = iph->tos;
17 	XFRM_MODE_SKB_CB(skb)->ttl = iph->ttl;
18 	XFRM_MODE_SKB_CB(skb)->optlen = iph->ihl * 4 - sizeof(*iph);
19 	memset(XFRM_MODE_SKB_CB(skb)->flow_lbl, 0,
20 	       sizeof(XFRM_MODE_SKB_CB(skb)->flow_lbl));
21 }
22 
23 static inline void xfrm6_extract_header(struct sk_buff *skb)
24 {
25 #if IS_ENABLED(CONFIG_IPV6)
26 	struct ipv6hdr *iph = ipv6_hdr(skb);
27 
28 	XFRM_MODE_SKB_CB(skb)->ihl = sizeof(*iph);
29 	XFRM_MODE_SKB_CB(skb)->id = 0;
30 	XFRM_MODE_SKB_CB(skb)->frag_off = htons(IP_DF);
31 	XFRM_MODE_SKB_CB(skb)->tos = ipv6_get_dsfield(iph);
32 	XFRM_MODE_SKB_CB(skb)->ttl = iph->hop_limit;
33 	XFRM_MODE_SKB_CB(skb)->optlen = 0;
34 	memcpy(XFRM_MODE_SKB_CB(skb)->flow_lbl, iph->flow_lbl,
35 	       sizeof(XFRM_MODE_SKB_CB(skb)->flow_lbl));
36 #else
37 	WARN_ON_ONCE(1);
38 #endif
39 }
40 
41 static inline void xfrm6_beet_make_header(struct sk_buff *skb)
42 {
43 	struct ipv6hdr *iph = ipv6_hdr(skb);
44 
45 	iph->version = 6;
46 
47 	memcpy(iph->flow_lbl, XFRM_MODE_SKB_CB(skb)->flow_lbl,
48 	       sizeof(iph->flow_lbl));
49 	iph->nexthdr = XFRM_MODE_SKB_CB(skb)->protocol;
50 
51 	ipv6_change_dsfield(iph, 0, XFRM_MODE_SKB_CB(skb)->tos);
52 	iph->hop_limit = XFRM_MODE_SKB_CB(skb)->ttl;
53 }
54 
55 static inline void xfrm4_beet_make_header(struct sk_buff *skb)
56 {
57 	struct iphdr *iph = ip_hdr(skb);
58 
59 	iph->ihl = 5;
60 	iph->version = 4;
61 
62 	iph->protocol = XFRM_MODE_SKB_CB(skb)->protocol;
63 	iph->tos = XFRM_MODE_SKB_CB(skb)->tos;
64 
65 	iph->id = XFRM_MODE_SKB_CB(skb)->id;
66 	iph->frag_off = XFRM_MODE_SKB_CB(skb)->frag_off;
67 	iph->ttl = XFRM_MODE_SKB_CB(skb)->ttl;
68 }
69 
70 #endif
71