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1#include <linux/errno.h>
2#include <linux/ip.h>
3#include <linux/kernel.h>
4#include <linux/module.h>
5#include <linux/skbuff.h>
6#include <linux/socket.h>
7#include <linux/types.h>
8#include <net/checksum.h>
9#include <net/ip.h>
10#include <net/ip6_fib.h>
11#include <net/lwtunnel.h>
12#include <net/protocol.h>
13#include <uapi/linux/ila.h>
14#include "ila.h"
15
16void ila_init_saved_csum(struct ila_params *p)
17{
18 if (!p->locator_match.v64)
19 return;
20
21 p->csum_diff = compute_csum_diff8(
22 (__be32 *)&p->locator,
23 (__be32 *)&p->locator_match);
24}
25
26static __wsum get_csum_diff_iaddr(struct ila_addr *iaddr, struct ila_params *p)
27{
28 if (p->locator_match.v64)
29 return p->csum_diff;
30 else
31 return compute_csum_diff8((__be32 *)&p->locator,
32 (__be32 *)&iaddr->loc);
33}
34
35static __wsum get_csum_diff(struct ipv6hdr *ip6h, struct ila_params *p)
36{
37 return get_csum_diff_iaddr(ila_a2i(&ip6h->daddr), p);
38}
39
40static void ila_csum_do_neutral_fmt(struct ila_addr *iaddr,
41 struct ila_params *p)
42{
43 __sum16 *adjust = (__force __sum16 *)&iaddr->ident.v16[3];
44 __wsum diff, fval;
45
46 diff = get_csum_diff_iaddr(iaddr, p);
47
48 fval = (__force __wsum)(ila_csum_neutral_set(iaddr->ident) ?
49 CSUM_NEUTRAL_FLAG : ~CSUM_NEUTRAL_FLAG);
50
51 diff = csum_add(diff, fval);
52
53 *adjust = ~csum_fold(csum_add(diff, csum_unfold(*adjust)));
54
55 /* Flip the csum-neutral bit. Either we are doing a SIR->ILA
56 * translation with ILA_CSUM_NEUTRAL_MAP as the csum_method
57 * and the C-bit is not set, or we are doing an ILA-SIR
58 * tranlsation and the C-bit is set.
59 */
60 iaddr->ident.csum_neutral ^= 1;
61}
62
63static void ila_csum_do_neutral_nofmt(struct ila_addr *iaddr,
64 struct ila_params *p)
65{
66 __sum16 *adjust = (__force __sum16 *)&iaddr->ident.v16[3];
67 __wsum diff;
68
69 diff = get_csum_diff_iaddr(iaddr, p);
70
71 *adjust = ~csum_fold(csum_add(diff, csum_unfold(*adjust)));
72}
73
74static void ila_csum_adjust_transport(struct sk_buff *skb,
75 struct ila_params *p)
76{
77 size_t nhoff = sizeof(struct ipv6hdr);
78 struct ipv6hdr *ip6h = ipv6_hdr(skb);
79 __wsum diff;
80
81 switch (ip6h->nexthdr) {
82 case NEXTHDR_TCP:
83 if (likely(pskb_may_pull(skb, nhoff + sizeof(struct tcphdr)))) {
84 struct tcphdr *th = (struct tcphdr *)
85 (skb_network_header(skb) + nhoff);
86
87 diff = get_csum_diff(ip6h, p);
88 inet_proto_csum_replace_by_diff(&th->check, skb,
89 diff, true);
90 }
91 break;
92 case NEXTHDR_UDP:
93 if (likely(pskb_may_pull(skb, nhoff + sizeof(struct udphdr)))) {
94 struct udphdr *uh = (struct udphdr *)
95 (skb_network_header(skb) + nhoff);
96
97 if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) {
98 diff = get_csum_diff(ip6h, p);
99 inet_proto_csum_replace_by_diff(&uh->check, skb,
100 diff, true);
101 if (!uh->check)
102 uh->check = CSUM_MANGLED_0;
103 }
104 }
105 break;
106 case NEXTHDR_ICMP:
107 if (likely(pskb_may_pull(skb,
108 nhoff + sizeof(struct icmp6hdr)))) {
109 struct icmp6hdr *ih = (struct icmp6hdr *)
110 (skb_network_header(skb) + nhoff);
111
112 diff = get_csum_diff(ip6h, p);
113 inet_proto_csum_replace_by_diff(&ih->icmp6_cksum, skb,
114 diff, true);
115 }
116 break;
117 }
118}
119
120void ila_update_ipv6_locator(struct sk_buff *skb, struct ila_params *p,
121 bool sir2ila)
122{
123 struct ipv6hdr *ip6h = ipv6_hdr(skb);
124 struct ila_addr *iaddr = ila_a2i(&ip6h->daddr);
125
126 switch (p->csum_mode) {
127 case ILA_CSUM_ADJUST_TRANSPORT:
128 ila_csum_adjust_transport(skb, p);
129 break;
130 case ILA_CSUM_NEUTRAL_MAP:
131 if (sir2ila) {
132 if (WARN_ON(ila_csum_neutral_set(iaddr->ident))) {
133 /* Checksum flag should never be
134 * set in a formatted SIR address.
135 */
136 break;
137 }
138 } else if (!ila_csum_neutral_set(iaddr->ident)) {
139 /* ILA to SIR translation and C-bit isn't
140 * set so we're good.
141 */
142 break;
143 }
144 ila_csum_do_neutral_fmt(iaddr, p);
145 break;
146 case ILA_CSUM_NEUTRAL_MAP_AUTO:
147 ila_csum_do_neutral_nofmt(iaddr, p);
148 break;
149 case ILA_CSUM_NO_ACTION:
150 break;
151 }
152
153 /* Now change destination address */
154 iaddr->loc = p->locator;
155}
1#include <linux/errno.h>
2#include <linux/ip.h>
3#include <linux/kernel.h>
4#include <linux/module.h>
5#include <linux/skbuff.h>
6#include <linux/socket.h>
7#include <linux/types.h>
8#include <net/checksum.h>
9#include <net/ip.h>
10#include <net/ip6_fib.h>
11#include <net/lwtunnel.h>
12#include <net/protocol.h>
13#include <uapi/linux/ila.h>
14#include "ila.h"
15
16static __wsum get_csum_diff(struct ipv6hdr *ip6h, struct ila_params *p)
17{
18 if (*(__be64 *)&ip6h->daddr == p->locator_match)
19 return p->csum_diff;
20 else
21 return compute_csum_diff8((__be32 *)&ip6h->daddr,
22 (__be32 *)&p->locator);
23}
24
25void update_ipv6_locator(struct sk_buff *skb, struct ila_params *p)
26{
27 __wsum diff;
28 struct ipv6hdr *ip6h = ipv6_hdr(skb);
29 size_t nhoff = sizeof(struct ipv6hdr);
30
31 /* First update checksum */
32 switch (ip6h->nexthdr) {
33 case NEXTHDR_TCP:
34 if (likely(pskb_may_pull(skb, nhoff + sizeof(struct tcphdr)))) {
35 struct tcphdr *th = (struct tcphdr *)
36 (skb_network_header(skb) + nhoff);
37
38 diff = get_csum_diff(ip6h, p);
39 inet_proto_csum_replace_by_diff(&th->check, skb,
40 diff, true);
41 }
42 break;
43 case NEXTHDR_UDP:
44 if (likely(pskb_may_pull(skb, nhoff + sizeof(struct udphdr)))) {
45 struct udphdr *uh = (struct udphdr *)
46 (skb_network_header(skb) + nhoff);
47
48 if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) {
49 diff = get_csum_diff(ip6h, p);
50 inet_proto_csum_replace_by_diff(&uh->check, skb,
51 diff, true);
52 if (!uh->check)
53 uh->check = CSUM_MANGLED_0;
54 }
55 }
56 break;
57 case NEXTHDR_ICMP:
58 if (likely(pskb_may_pull(skb,
59 nhoff + sizeof(struct icmp6hdr)))) {
60 struct icmp6hdr *ih = (struct icmp6hdr *)
61 (skb_network_header(skb) + nhoff);
62
63 diff = get_csum_diff(ip6h, p);
64 inet_proto_csum_replace_by_diff(&ih->icmp6_cksum, skb,
65 diff, true);
66 }
67 break;
68 }
69
70 /* Now change destination address */
71 *(__be64 *)&ip6h->daddr = p->locator;
72}
73
74static int __init ila_init(void)
75{
76 int ret;
77
78 ret = ila_lwt_init();
79
80 if (ret)
81 goto fail_lwt;
82
83 ret = ila_xlat_init();
84 if (ret)
85 goto fail_xlat;
86
87 return 0;
88fail_xlat:
89 ila_lwt_fini();
90fail_lwt:
91 return ret;
92}
93
94static void __exit ila_fini(void)
95{
96 ila_xlat_fini();
97 ila_lwt_fini();
98}
99
100module_init(ila_init);
101module_exit(ila_fini);
102MODULE_ALIAS_RTNL_LWT(ILA);
103MODULE_AUTHOR("Tom Herbert <tom@herbertland.com>");
104MODULE_LICENSE("GPL");