diff options
Diffstat (limited to 'net')
| -rw-r--r-- | net/ipv6/seg6_iptunnel.c | 128 |
1 files changed, 127 insertions, 1 deletions
diff --git a/net/ipv6/seg6_iptunnel.c b/net/ipv6/seg6_iptunnel.c index e756ba705fd9..454bd8a838e6 100644 --- a/net/ipv6/seg6_iptunnel.c +++ b/net/ipv6/seg6_iptunnel.c @@ -36,6 +36,7 @@ static size_t seg6_lwt_headroom(struct seg6_iptunnel_encap *tuninfo) case SEG6_IPTUN_MODE_INLINE: break; case SEG6_IPTUN_MODE_ENCAP: + case SEG6_IPTUN_MODE_ENCAP_RED: head = sizeof(struct ipv6hdr); break; case SEG6_IPTUN_MODE_L2ENCAP: @@ -197,6 +198,124 @@ int seg6_do_srh_encap(struct sk_buff *skb, struct ipv6_sr_hdr *osrh, int proto) } EXPORT_SYMBOL_GPL(seg6_do_srh_encap); +/* encapsulate an IPv6 packet within an outer IPv6 header with reduced SRH */ +static int seg6_do_srh_encap_red(struct sk_buff *skb, + struct ipv6_sr_hdr *osrh, int proto) +{ + __u8 first_seg = osrh->first_segment; + struct dst_entry *dst = skb_dst(skb); + struct net *net = dev_net(dst->dev); + struct ipv6hdr *hdr, *inner_hdr; + int hdrlen = ipv6_optlen(osrh); + int red_tlv_offset, tlv_offset; + struct ipv6_sr_hdr *isrh; + bool skip_srh = false; + __be32 flowlabel; + int tot_len, err; + int red_hdrlen; + int tlvs_len; + + if (first_seg > 0) { + red_hdrlen = hdrlen - sizeof(struct in6_addr); + } else { + /* NOTE: if tag/flags and/or other TLVs are introduced in the + * seg6_iptunnel infrastructure, they should be considered when + * deciding to skip the SRH. + */ + skip_srh = !sr_has_hmac(osrh); + + red_hdrlen = skip_srh ? 0 : hdrlen; + } + + tot_len = red_hdrlen + sizeof(struct ipv6hdr); + + err = skb_cow_head(skb, tot_len + skb->mac_len); + if (unlikely(err)) + return err; + + inner_hdr = ipv6_hdr(skb); + flowlabel = seg6_make_flowlabel(net, skb, inner_hdr); + + skb_push(skb, tot_len); + skb_reset_network_header(skb); + skb_mac_header_rebuild(skb); + hdr = ipv6_hdr(skb); + + /* based on seg6_do_srh_encap() */ + if (skb->protocol == htons(ETH_P_IPV6)) { + ip6_flow_hdr(hdr, ip6_tclass(ip6_flowinfo(inner_hdr)), + flowlabel); + hdr->hop_limit = inner_hdr->hop_limit; + } else { + ip6_flow_hdr(hdr, 0, flowlabel); + hdr->hop_limit = ip6_dst_hoplimit(skb_dst(skb)); + + memset(IP6CB(skb), 0, sizeof(*IP6CB(skb))); + IP6CB(skb)->iif = skb->skb_iif; + } + + /* no matter if we have to skip the SRH or not, the first segment + * always comes in the pushed IPv6 header. + */ + hdr->daddr = osrh->segments[first_seg]; + + if (skip_srh) { + hdr->nexthdr = proto; + + set_tun_src(net, dst->dev, &hdr->daddr, &hdr->saddr); + goto out; + } + + /* we cannot skip the SRH, slow path */ + + hdr->nexthdr = NEXTHDR_ROUTING; + isrh = (void *)hdr + sizeof(struct ipv6hdr); + + if (unlikely(!first_seg)) { + /* this is a very rare case; we have only one SID but + * we cannot skip the SRH since we are carrying some + * other info. + */ + memcpy(isrh, osrh, hdrlen); + goto srcaddr; + } + + tlv_offset = sizeof(*osrh) + (first_seg + 1) * sizeof(struct in6_addr); + red_tlv_offset = tlv_offset - sizeof(struct in6_addr); + + memcpy(isrh, osrh, red_tlv_offset); + + tlvs_len = hdrlen - tlv_offset; + if (unlikely(tlvs_len > 0)) { + const void *s = (const void *)osrh + tlv_offset; + void *d = (void *)isrh + red_tlv_offset; + + memcpy(d, s, tlvs_len); + } + + --isrh->first_segment; + isrh->hdrlen -= 2; + +srcaddr: + isrh->nexthdr = proto; + set_tun_src(net, dst->dev, &hdr->daddr, &hdr->saddr); + +#ifdef CONFIG_IPV6_SEG6_HMAC + if (unlikely(!skip_srh && sr_has_hmac(isrh))) { + err = seg6_push_hmac(net, &hdr->saddr, isrh); + if (unlikely(err)) + return err; + } +#endif + +out: + hdr->payload_len = htons(skb->len - sizeof(struct ipv6hdr)); + + skb_postpush_rcsum(skb, hdr, tot_len); + + return 0; +} + /* insert an SRH within an IPv6 packet, just after the IPv6 header */ int seg6_do_srh_inline(struct sk_buff *skb, struct ipv6_sr_hdr *osrh) { @@ -269,6 +388,7 @@ static int seg6_do_srh(struct sk_buff *skb) return err; break; case SEG6_IPTUN_MODE_ENCAP: + case SEG6_IPTUN_MODE_ENCAP_RED: err = iptunnel_handle_offloads(skb, SKB_GSO_IPXIP6); if (err) return err; @@ -280,7 +400,11 @@ static int seg6_do_srh(struct sk_buff *skb) else return -EINVAL; - err = seg6_do_srh_encap(skb, tinfo->srh, proto); + if (tinfo->mode == SEG6_IPTUN_MODE_ENCAP) + err = seg6_do_srh_encap(skb, tinfo->srh, proto); + else + err = seg6_do_srh_encap_red(skb, tinfo->srh, proto); + if (err) return err; @@ -517,6 +641,8 @@ static int seg6_build_state(struct net *net, struct nlattr *nla, break; case SEG6_IPTUN_MODE_L2ENCAP: break; + case SEG6_IPTUN_MODE_ENCAP_RED: + break; default: return -EINVAL; } |