summaryrefslogtreecommitdiff
path: root/net/ipv6/seg6_iptunnel.c
diff options
context:
space:
mode:
Diffstat (limited to 'net/ipv6/seg6_iptunnel.c')
-rw-r--r--net/ipv6/seg6_iptunnel.c140
1 files changed, 138 insertions, 2 deletions
diff --git a/net/ipv6/seg6_iptunnel.c b/net/ipv6/seg6_iptunnel.c
index e756ba705fd9..34db881204d2 100644
--- a/net/ipv6/seg6_iptunnel.c
+++ b/net/ipv6/seg6_iptunnel.c
@@ -36,9 +36,11 @@ 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:
+ case SEG6_IPTUN_MODE_L2ENCAP_RED:
return 0;
}
@@ -197,6 +199,124 @@ 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 +389,7 @@ 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 +401,11 @@ 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;
@@ -289,6 +414,7 @@ static int seg6_do_srh(struct sk_buff *skb)
skb->protocol = htons(ETH_P_IPV6);
break;
case SEG6_IPTUN_MODE_L2ENCAP:
+ case SEG6_IPTUN_MODE_L2ENCAP_RED:
if (!skb_mac_header_was_set(skb))
return -EINVAL;
@@ -298,7 +424,13 @@ static int seg6_do_srh(struct sk_buff *skb)
skb_mac_header_rebuild(skb);
skb_push(skb, skb->mac_len);
- err = seg6_do_srh_encap(skb, tinfo->srh, IPPROTO_ETHERNET);
+ if (tinfo->mode == SEG6_IPTUN_MODE_L2ENCAP)
+ err = seg6_do_srh_encap(skb, tinfo->srh,
+ IPPROTO_ETHERNET);
+ else
+ err = seg6_do_srh_encap_red(skb, tinfo->srh,
+ IPPROTO_ETHERNET);
+
if (err)
return err;
@@ -517,6 +649,10 @@ 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;
+ case SEG6_IPTUN_MODE_L2ENCAP_RED:
+ break;
default:
return -EINVAL;
}