| Cong Wang | acb3e04 | 2013-01-07 20:52:40 +0000 | [diff] [blame] | 1 | #include <net/ip.h> |
| 2 | #include <net/udp.h> |
| 3 | #include <net/udplite.h> |
| 4 | #include <asm/checksum.h> |
| 5 | |
| 6 | #ifndef _HAVE_ARCH_IPV6_CSUM |
| 7 | __sum16 csum_ipv6_magic(const struct in6_addr *saddr, |
| 8 | const struct in6_addr *daddr, |
| 9 | __u32 len, unsigned short proto, |
| 10 | __wsum csum) |
| 11 | { |
| 12 | |
| 13 | int carry; |
| 14 | __u32 ulen; |
| 15 | __u32 uproto; |
| 16 | __u32 sum = (__force u32)csum; |
| 17 | |
| 18 | sum += (__force u32)saddr->s6_addr32[0]; |
| 19 | carry = (sum < (__force u32)saddr->s6_addr32[0]); |
| 20 | sum += carry; |
| 21 | |
| 22 | sum += (__force u32)saddr->s6_addr32[1]; |
| 23 | carry = (sum < (__force u32)saddr->s6_addr32[1]); |
| 24 | sum += carry; |
| 25 | |
| 26 | sum += (__force u32)saddr->s6_addr32[2]; |
| 27 | carry = (sum < (__force u32)saddr->s6_addr32[2]); |
| 28 | sum += carry; |
| 29 | |
| 30 | sum += (__force u32)saddr->s6_addr32[3]; |
| 31 | carry = (sum < (__force u32)saddr->s6_addr32[3]); |
| 32 | sum += carry; |
| 33 | |
| 34 | sum += (__force u32)daddr->s6_addr32[0]; |
| 35 | carry = (sum < (__force u32)daddr->s6_addr32[0]); |
| 36 | sum += carry; |
| 37 | |
| 38 | sum += (__force u32)daddr->s6_addr32[1]; |
| 39 | carry = (sum < (__force u32)daddr->s6_addr32[1]); |
| 40 | sum += carry; |
| 41 | |
| 42 | sum += (__force u32)daddr->s6_addr32[2]; |
| 43 | carry = (sum < (__force u32)daddr->s6_addr32[2]); |
| 44 | sum += carry; |
| 45 | |
| 46 | sum += (__force u32)daddr->s6_addr32[3]; |
| 47 | carry = (sum < (__force u32)daddr->s6_addr32[3]); |
| 48 | sum += carry; |
| 49 | |
| 50 | ulen = (__force u32)htonl((__u32) len); |
| 51 | sum += ulen; |
| 52 | carry = (sum < ulen); |
| 53 | sum += carry; |
| 54 | |
| 55 | uproto = (__force u32)htonl(proto); |
| 56 | sum += uproto; |
| 57 | carry = (sum < uproto); |
| 58 | sum += carry; |
| 59 | |
| 60 | return csum_fold((__force __wsum)sum); |
| 61 | } |
| 62 | EXPORT_SYMBOL(csum_ipv6_magic); |
| 63 | #endif |
| 64 | |
| 65 | int udp6_csum_init(struct sk_buff *skb, struct udphdr *uh, int proto) |
| 66 | { |
| 67 | int err; |
| 68 | |
| 69 | UDP_SKB_CB(skb)->partial_cov = 0; |
| 70 | UDP_SKB_CB(skb)->cscov = skb->len; |
| 71 | |
| 72 | if (proto == IPPROTO_UDPLITE) { |
| 73 | err = udplite_checksum_init(skb, uh); |
| 74 | if (err) |
| 75 | return err; |
| 76 | } |
| 77 | |
| Tom Herbert | 4068579 | 2014-05-02 16:29:58 -0700 | [diff] [blame] | 78 | /* To support RFC 6936 (allow zero checksum in UDP/IPV6 for tunnels) |
| 79 | * we accept a checksum of zero here. When we find the socket |
| 80 | * for the UDP packet we'll check if that socket allows zero checksum |
| 81 | * for IPv6 (set by socket option). |
| 82 | */ |
| 83 | return skb_checksum_init_zero_check(skb, proto, uh->check, |
| 84 | ip6_compute_pseudo); |
| Cong Wang | acb3e04 | 2013-01-07 20:52:40 +0000 | [diff] [blame] | 85 | } |
| 86 | EXPORT_SYMBOL(udp6_csum_init); |