projects / linux-2.6-block.git / blame
| Commit | Line | Data |
|---|---|---|
| b2441318 | 1 | /* SPDX-License-Identifier: GPL-2.0 */ |
| ba4e58ec GR |
2 | /* |
| 3 | * Definitions for the UDP-Lite (RFC 3828) code. | |
| 4 | */ | |
| 5 | #ifndef _UDPLITE_H | |
| 6 | #define _UDPLITE_H | |
| 7 | ||
| 6bb100b9 | 8 | #include <net/ip6_checksum.h> |
| 949d6b40 | 9 | #include <net/udp.h> |
| 6bb100b9 | 10 | |
| ba4e58ec GR |
11 | /* UDP-Lite socket options */ |
| 12 | #define UDPLITE_SEND_CSCOV 10 /* sender partial coverage (as sent) */ | |
| 13 | #define UDPLITE_RECV_CSCOV 11 /* receiver partial coverage (threshold ) */ | |
| 14 | ||
| 15 | extern struct proto udplite_prot; | |
| 645ca708 | 16 | extern struct udp_table udplite_table; |
| ba4e58ec | 17 | |
| ba4e58ec GR |
18 | /* |
| 19 | * Checksum computation is all in software, hence simpler getfrag. | |
| 20 | */ | |
| 21 | static __inline__ int udplite_getfrag(void *from, char *to, int offset, | |
| 22 | int len, int odd, struct sk_buff *skb) | |
| 23 | { | |
| f69e6d13 | 24 | struct msghdr *msg = from; |
| 0b62fca2 | 25 | return copy_from_iter_full(to, len, &msg->msg_iter) ? 0 : -EFAULT; |
| ba4e58ec GR |
26 | } |
| 27 | ||
| ba4e58ec GR |
28 | /* |
| 29 | * Checksumming routines | |
| 30 | */ | |
| 31 | static inline int udplite_checksum_init(struct sk_buff *skb, struct udphdr *uh) | |
| 32 | { | |
| 33 | u16 cscov; | |
| 34 | ||
| 35 | /* In UDPv4 a zero checksum means that the transmitter generated no | |
| 36 | * checksum. UDP-Lite (like IPv6) mandates checksums, hence packets | |
| 37 | * with a zero checksum field are illegal. */ | |
| 38 | if (uh->check == 0) { | |
| ba7a46f1 | 39 | net_dbg_ratelimited("UDPLite: zeroed checksum field\n"); |
| ba4e58ec GR |
40 | return 1; |
| 41 | } | |
| 42 | ||
| ba4e58ec GR |
43 | cscov = ntohs(uh->len); |
| 44 | ||
| 45 | if (cscov == 0) /* Indicates that full coverage is required. */ | |
| 759e5d00 | 46 | ; |
| ba4e58ec GR |
47 | else if (cscov < 8 || cscov > skb->len) { |
| 48 | /* | |
| 49 | * Coverage length violates RFC 3828: log and discard silently. | |
| 50 | */ | |
| ba7a46f1 JP |
51 | net_dbg_ratelimited("UDPLite: bad csum coverage %d/%d\n", |
| 52 | cscov, skb->len); | |
| ba4e58ec GR |
53 | return 1; |
| 54 | ||
| 759e5d00 | 55 | } else if (cscov < skb->len) { |
| ba4e58ec | 56 | UDP_SKB_CB(skb)->partial_cov = 1; |
| 759e5d00 HX |
57 | UDP_SKB_CB(skb)->cscov = cscov; |
| 58 | if (skb->ip_summed == CHECKSUM_COMPLETE) | |
| 59 | skb->ip_summed = CHECKSUM_NONE; | |
| 15f35d49 | 60 | skb->csum_valid = 0; |
| 759e5d00 | 61 | } |
| ba4e58ec GR |
62 | |
| 63 | return 0; | |
| 64 | } | |
| 65 | ||
| f36c23bb | 66 | /* Fast-path computation of checksum. Socket may not be locked. */ |
| f6b9664f HX |
67 | static inline __wsum udplite_csum(struct sk_buff *skb) |
| 68 | { | |
| f36c23bb | 69 | const struct udp_sock *up = udp_sk(skb->sk); |
| f6b9664f | 70 | const int off = skb_transport_offset(skb); |
| f36c23bb | 71 | int len = skb->len - off; |
| f6b9664f | 72 | |
| f36c23bb GR |
73 | if ((up->pcflag & UDPLITE_SEND_CC) && up->pcslen < len) { |
| 74 | if (0 < up->pcslen) | |
| 75 | len = up->pcslen; | |
| 76 | udp_hdr(skb)->len = htons(up->pcslen); | |
| 77 | } | |
| f6b9664f HX |
78 | skb->ip_summed = CHECKSUM_NONE; /* no HW support for checksumming */ |
| 79 | ||
| f36c23bb | 80 | return skb_checksum(skb, off, len, 0); |
| f6b9664f HX |
81 | } |
| 82 | ||
| 16073439 JP |
83 | void udplite4_register(void); |
| 84 | int udplite_get_port(struct sock *sk, unsigned short snum, | |
| 85 | int (*scmp)(const struct sock *, const struct sock *)); | |
| ba4e58ec | 86 | #endif /* _UDPLITE_H */ |