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