1
2
3
4
5#ifndef _UDPLITE_H
6#define _UDPLITE_H
7
8#include <net/ip6_checksum.h>
9
10
11#define UDPLITE_SEND_CSCOV 10
12#define UDPLITE_RECV_CSCOV 11
13
14extern struct proto udplite_prot;
15extern struct udp_table udplite_table;
16
17
18
19
20static __inline__ int udplite_getfrag(void *from, char *to, int offset,
21 int len, int odd, struct sk_buff *skb)
22{
23 struct msghdr *msg = from;
24 return copy_from_iter_full(to, len, &msg->msg_iter) ? 0 : -EFAULT;
25}
26
27
28static inline int udplite_sk_init(struct sock *sk)
29{
30 udp_init_sock(sk);
31 udp_sk(sk)->pcflag = UDPLITE_BIT;
32 return 0;
33}
34
35
36
37
38static inline int udplite_checksum_init(struct sk_buff *skb, struct udphdr *uh)
39{
40 u16 cscov;
41
42
43
44
45 if (uh->check == 0) {
46 net_dbg_ratelimited("UDPLite: zeroed checksum field\n");
47 return 1;
48 }
49
50 cscov = ntohs(uh->len);
51
52 if (cscov == 0)
53 ;
54 else if (cscov < 8 || cscov > skb->len) {
55
56
57
58 net_dbg_ratelimited("UDPLite: bad csum coverage %d/%d\n",
59 cscov, skb->len);
60 return 1;
61
62 } else if (cscov < skb->len) {
63 UDP_SKB_CB(skb)->partial_cov = 1;
64 UDP_SKB_CB(skb)->cscov = cscov;
65 if (skb->ip_summed == CHECKSUM_COMPLETE)
66 skb->ip_summed = CHECKSUM_NONE;
67 skb->csum_valid = 0;
68 }
69
70 return 0;
71}
72
73
74static inline __wsum udplite_csum_outgoing(struct sock *sk, struct sk_buff *skb)
75{
76 const struct udp_sock *up = udp_sk(skb->sk);
77 int cscov = up->len;
78 __wsum csum = 0;
79
80 if (up->pcflag & UDPLITE_SEND_CC) {
81
82
83
84
85 if (up->pcslen < up->len) {
86 if (0 < up->pcslen)
87 cscov = up->pcslen;
88 udp_hdr(skb)->len = htons(up->pcslen);
89 }
90
91
92
93
94
95
96
97
98
99
100 }
101
102 skb->ip_summed = CHECKSUM_NONE;
103
104 skb_queue_walk(&sk->sk_write_queue, skb) {
105 const int off = skb_transport_offset(skb);
106 const int len = skb->len - off;
107
108 csum = skb_checksum(skb, off, (cscov > len)? len : cscov, csum);
109
110 if ((cscov -= len) <= 0)
111 break;
112 }
113 return csum;
114}
115
116
117static inline __wsum udplite_csum(struct sk_buff *skb)
118{
119 const struct udp_sock *up = udp_sk(skb->sk);
120 const int off = skb_transport_offset(skb);
121 int len = skb->len - off;
122
123 if ((up->pcflag & UDPLITE_SEND_CC) && up->pcslen < len) {
124 if (0 < up->pcslen)
125 len = up->pcslen;
126 udp_hdr(skb)->len = htons(up->pcslen);
127 }
128 skb->ip_summed = CHECKSUM_NONE;
129
130 return skb_checksum(skb, off, len, 0);
131}
132
133void udplite4_register(void);
134int udplite_get_port(struct sock *sk, unsigned short snum,
135 int (*scmp)(const struct sock *, const struct sock *));
136#endif
137