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Release 4.15 net/ipv6/udp_offload.c

Directory: net/ipv6
/*
 *      IPV6 GSO/GRO offload support
 *      Linux INET6 implementation
 *
 *      This program is free software; you can redistribute it and/or
 *      modify it under the terms of the GNU General Public License
 *      as published by the Free Software Foundation; either version
 *      2 of the License, or (at your option) any later version.
 *
 *      UDPv6 GSO support
 */
#include <linux/skbuff.h>
#include <linux/netdevice.h>
#include <net/protocol.h>
#include <net/ipv6.h>
#include <net/udp.h>
#include <net/ip6_checksum.h>
#include "ip6_offload.h"


static struct sk_buff *udp6_ufo_fragment(struct sk_buff *skb, netdev_features_t features) { struct sk_buff *segs = ERR_PTR(-EINVAL); unsigned int mss; unsigned int unfrag_ip6hlen, unfrag_len; struct frag_hdr *fptr; u8 *packet_start, *prevhdr; u8 nexthdr; u8 frag_hdr_sz = sizeof(struct frag_hdr); __wsum csum; int tnl_hlen; int err; mss = skb_shinfo(skb)->gso_size; if (unlikely(skb->len <= mss)) goto out; if (skb->encapsulation && skb_shinfo(skb)->gso_type & (SKB_GSO_UDP_TUNNEL|SKB_GSO_UDP_TUNNEL_CSUM)) segs = skb_udp_tunnel_segment(skb, features, true); else { const struct ipv6hdr *ipv6h; struct udphdr *uh; if (!(skb_shinfo(skb)->gso_type & SKB_GSO_UDP)) goto out; if (!pskb_may_pull(skb, sizeof(struct udphdr))) goto out; /* Do software UFO. Complete and fill in the UDP checksum as HW cannot * do checksum of UDP packets sent as multiple IP fragments. */ uh = udp_hdr(skb); ipv6h = ipv6_hdr(skb); uh->check = 0; csum = skb_checksum(skb, 0, skb->len, 0); uh->check = udp_v6_check(skb->len, &ipv6h->saddr, &ipv6h->daddr, csum); if (uh->check == 0) uh->check = CSUM_MANGLED_0; skb->ip_summed = CHECKSUM_UNNECESSARY; /* If there is no outer header we can fake a checksum offload * due to the fact that we have already done the checksum in * software prior to segmenting the frame. */ if (!skb->encap_hdr_csum) features |= NETIF_F_HW_CSUM; /* Check if there is enough headroom to insert fragment header. */ tnl_hlen = skb_tnl_header_len(skb); if (skb->mac_header < (tnl_hlen + frag_hdr_sz)) { if (gso_pskb_expand_head(skb, tnl_hlen + frag_hdr_sz)) goto out; } /* Find the unfragmentable header and shift it left by frag_hdr_sz * bytes to insert fragment header. */ err = ip6_find_1stfragopt(skb, &prevhdr); if (err < 0) return ERR_PTR(err); unfrag_ip6hlen = err; nexthdr = *prevhdr; *prevhdr = NEXTHDR_FRAGMENT; unfrag_len = (skb_network_header(skb) - skb_mac_header(skb)) + unfrag_ip6hlen + tnl_hlen; packet_start = (u8 *) skb->head + SKB_GSO_CB(skb)->mac_offset; memmove(packet_start-frag_hdr_sz, packet_start, unfrag_len); SKB_GSO_CB(skb)->mac_offset -= frag_hdr_sz; skb->mac_header -= frag_hdr_sz; skb->network_header -= frag_hdr_sz; fptr = (struct frag_hdr *)(skb_network_header(skb) + unfrag_ip6hlen); fptr->nexthdr = nexthdr; fptr->reserved = 0; fptr->identification = ipv6_proxy_select_ident(dev_net(skb->dev), skb); /* Fragment the skb. ipv6 header and the remaining fields of the * fragment header are updated in ipv6_gso_segment() */ segs = skb_segment(skb, features); } out: return segs; }

Contributors

PersonTokensPropCommitsCommitProp
Willem de Bruijn40287.20%228.57%
Vlad Yasevich296.29%114.29%
Américo Wang245.21%228.57%
Tom Herbert61.30%228.57%
Total461100.00%7100.00%


static struct sk_buff **udp6_gro_receive(struct sk_buff **head, struct sk_buff *skb) { struct udphdr *uh = udp_gro_udphdr(skb); if (unlikely(!uh)) goto flush; /* Don't bother verifying checksum if we're going to flush anyway. */ if (NAPI_GRO_CB(skb)->flush) goto skip; if (skb_gro_checksum_validate_zero_check(skb, IPPROTO_UDP, uh->check, ip6_gro_compute_pseudo)) goto flush; else if (uh->check) skb_gro_checksum_try_convert(skb, IPPROTO_UDP, uh->check, ip6_gro_compute_pseudo); skip: NAPI_GRO_CB(skb)->is_ipv6 = 1; return udp_gro_receive(head, skb, uh, udp6_lib_lookup_skb); flush: NAPI_GRO_CB(skb)->flush = 1; return NULL; }

Contributors

PersonTokensPropCommitsCommitProp
Tom Herbert129100.00%4100.00%
Total129100.00%4100.00%


static int udp6_gro_complete(struct sk_buff *skb, int nhoff) { const struct ipv6hdr *ipv6h = ipv6_hdr(skb); struct udphdr *uh = (struct udphdr *)(skb->data + nhoff); if (uh->check) { skb_shinfo(skb)->gso_type |= SKB_GSO_UDP_TUNNEL_CSUM; uh->check = ~udp_v6_check(skb->len - nhoff, &ipv6h->saddr, &ipv6h->daddr, 0); } else { skb_shinfo(skb)->gso_type |= SKB_GSO_UDP_TUNNEL; } return udp_gro_complete(skb, nhoff, udp6_lib_lookup_skb); }

Contributors

PersonTokensPropCommitsCommitProp
Tom Herbert10799.07%375.00%
Eric Dumazet10.93%125.00%
Total108100.00%4100.00%

static const struct net_offload udpv6_offload = { .callbacks = { .gso_segment = udp6_ufo_fragment, .gro_receive = udp6_gro_receive, .gro_complete = udp6_gro_complete, }, };
int udpv6_offload_init(void) { return inet6_add_offload(&udpv6_offload, IPPROTO_UDP); }

Contributors

PersonTokensPropCommitsCommitProp
Vlad Yasevich1593.75%150.00%
Tom Herbert16.25%150.00%
Total16100.00%2100.00%


int udpv6_offload_exit(void) { return inet6_del_offload(&udpv6_offload, IPPROTO_UDP); }

Contributors

PersonTokensPropCommitsCommitProp
Tom Herbert16100.00%1100.00%
Total16100.00%1100.00%


Overall Contributors

PersonTokensPropCommitsCommitProp
Willem de Bruijn40351.67%213.33%
Tom Herbert27234.87%746.67%
Vlad Yasevich8010.26%320.00%
Américo Wang243.08%213.33%
Eric Dumazet10.13%16.67%
Total780100.00%15100.00%
Directory: net/ipv6
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