Greg Kroah-Hartman | b244131 | 2017-11-01 15:07:57 +0100 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0 |
Cong Wang | acb3e04 | 2013-01-07 20:52:40 +0000 | [diff] [blame] | 2 | #include <net/ip.h> |
| 3 | #include <net/udp.h> |
| 4 | #include <net/udplite.h> |
| 5 | #include <asm/checksum.h> |
| 6 | |
| 7 | #ifndef _HAVE_ARCH_IPV6_CSUM |
| 8 | __sum16 csum_ipv6_magic(const struct in6_addr *saddr, |
| 9 | const struct in6_addr *daddr, |
Alexander Duyck | 1e94082 | 2016-03-11 14:05:41 -0800 | [diff] [blame] | 10 | __u32 len, __u8 proto, __wsum csum) |
Cong Wang | acb3e04 | 2013-01-07 20:52:40 +0000 | [diff] [blame] | 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). |
Hannes Frederic Sowa | c148d16 | 2016-06-11 21:15:37 +0200 | [diff] [blame] | 82 | * |
| 83 | * Note, we are only interested in != 0 or == 0, thus the |
| 84 | * force to int. |
Tom Herbert | 4068579 | 2014-05-02 16:29:58 -0700 | [diff] [blame] | 85 | */ |
Hannes Frederic Sowa | c148d16 | 2016-06-11 21:15:37 +0200 | [diff] [blame] | 86 | return (__force int)skb_checksum_init_zero_check(skb, proto, uh->check, |
| 87 | ip6_compute_pseudo); |
Cong Wang | acb3e04 | 2013-01-07 20:52:40 +0000 | [diff] [blame] | 88 | } |
| 89 | EXPORT_SYMBOL(udp6_csum_init); |
Tom Herbert | af5fcba | 2014-06-04 17:19:48 -0700 | [diff] [blame] | 90 | |
| 91 | /* Function to set UDP checksum for an IPv6 UDP packet. This is intended |
| 92 | * for the simple case like when setting the checksum for a UDP tunnel. |
| 93 | */ |
| 94 | void udp6_set_csum(bool nocheck, struct sk_buff *skb, |
| 95 | const struct in6_addr *saddr, |
| 96 | const struct in6_addr *daddr, int len) |
| 97 | { |
| 98 | struct udphdr *uh = udp_hdr(skb); |
| 99 | |
| 100 | if (nocheck) |
| 101 | uh->check = 0; |
| 102 | else if (skb_is_gso(skb)) |
| 103 | uh->check = ~udp_v6_check(len, saddr, daddr, 0); |
Edward Cree | 179bc67 | 2016-02-11 20:48:04 +0000 | [diff] [blame] | 104 | else if (skb->ip_summed == CHECKSUM_PARTIAL) { |
| 105 | uh->check = 0; |
| 106 | uh->check = udp_v6_check(len, saddr, daddr, lco_csum(skb)); |
| 107 | if (uh->check == 0) |
| 108 | uh->check = CSUM_MANGLED_0; |
Edward Cree | d75f130 | 2016-02-11 20:49:40 +0000 | [diff] [blame] | 109 | } else { |
Tom Herbert | af5fcba | 2014-06-04 17:19:48 -0700 | [diff] [blame] | 110 | skb->ip_summed = CHECKSUM_PARTIAL; |
| 111 | skb->csum_start = skb_transport_header(skb) - skb->head; |
| 112 | skb->csum_offset = offsetof(struct udphdr, check); |
| 113 | uh->check = ~udp_v6_check(len, saddr, daddr, 0); |
Tom Herbert | af5fcba | 2014-06-04 17:19:48 -0700 | [diff] [blame] | 114 | } |
| 115 | } |
| 116 | EXPORT_SYMBOL(udp6_set_csum); |