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net: openvswitch: IPv6: Add IPv6 extension header support

PATCH Superseded Toms Atteka 2 participants 2 messages May 6, 2021

Subsystems (3)
Networking Network drivers Openvswitch

v1 of 8 Superseded Latest is v8 →

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Toms Atteka

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PATCH 1/1 net: openvswitch: IPv6: Add IPv6 extension header support

IPv6 extension headers carry optional internet layer information and are placed between the fixed header and the upper-layer protocol header.

This change adds a new OpenFlow field OFPXMT_OFB_IPV6_EXTHDR and packets can be filtered using ipv6_ext flag.

Tested-at: https://github.com/TomCodeLV/ovs/actions/runs/504185214

Signed-off-by Toms Atteka <[email protected]>
---
 include/uapi/linux/openvswitch.h |   1 +
 net/openvswitch/flow.c           | 141 +++++++++++++++++++++++++++++++
 net/openvswitch/flow.h           |  14 +++
 net/openvswitch/flow_netlink.c   |   5 +-
 4 files changed, 160 insertions(+), 1 deletion(-)
include/uapi/linux/openvswitch.h +1 -0
index 8d16744edc31..a19812b6631a 100644
@@ -420,6 +420,7 @@ struct ovs_key_ipv6 {
 	__u8   ipv6_tclass;
 	__u8   ipv6_hlimit;
 	__u8   ipv6_frag;	/* One of OVS_FRAG_TYPE_*. */
+	__u16  ipv6_exthdr;
 };
 
 struct ovs_key_tcp {
net/openvswitch/flow.c +141 -0

153 lines not on this page · raw message

net/openvswitch/flow.h +14 -0
index 758a8c77f736..e7a8eafae272 100644
@@ -32,6 +32,19 @@ enum sw_flow_mac_proto {
 #define SW_FLOW_KEY_INVALID	0x80
 #define MPLS_LABEL_DEPTH       3
 
+/* Bit definitions for IPv6 Extension Header pseudo-field. */
+enum ofp12_ipv6exthdr_flags {
+	OFPIEH12_NONEXT = 1 << 0,   /* "No next header" encountered. */
+	OFPIEH12_ESP    = 1 << 1,   /* Encrypted Sec Payload header present. */
+	OFPIEH12_AUTH   = 1 << 2,   /* Authentication header present. */
+	OFPIEH12_DEST   = 1 << 3,   /* 1 or 2 dest headers present. */
+	OFPIEH12_FRAG   = 1 << 4,   /* Fragment header present. */
+	OFPIEH12_ROUTER = 1 << 5,   /* Router header present. */
+	OFPIEH12_HOP    = 1 << 6,   /* Hop-by-hop header present. */
+	OFPIEH12_UNREP  = 1 << 7,   /* Unexpected repeats encountered. */
+	OFPIEH12_UNSEQ  = 1 << 8    /* Unexpected sequencing encountered. */
+};
+
 /* Store options at the end of the array if they are less than the
  * maximum size. This allows us to get the benefits of variable length
  * matching for small options.

@@ -121,6 +134,7 @@ struct sw_flow_key {
 				struct in6_addr dst;	/* IPv6 destination address. */
 			} addr;
 			__be32 label;			/* IPv6 flow label. */
+			u16 exthdrs;			/* IPv6 extension header flags */
 			union {
 				struct {
 					struct in6_addr src;
net/openvswitch/flow_netlink.c +4 -1
index fd1f809e9bc1..681cd9ddda4a 100644
@@ -367,7 +367,7 @@ size_t ovs_key_attr_size(void)
 		+ nla_total_size(4)   /* OVS_KEY_ATTR_VLAN */
 		+ nla_total_size(0)   /* OVS_KEY_ATTR_ENCAP */
 		+ nla_total_size(2)   /* OVS_KEY_ATTR_ETHERTYPE */
-		+ nla_total_size(40)  /* OVS_KEY_ATTR_IPV6 */
+		+ nla_total_size(42)  /* OVS_KEY_ATTR_IPV6 */
 		+ nla_total_size(2)   /* OVS_KEY_ATTR_ICMPV6 */
 		+ nla_total_size(28); /* OVS_KEY_ATTR_ND */
 }

@@ -1585,6 +1585,8 @@ static int ovs_key_from_nlattrs(struct net *net, struct sw_flow_match *match,
 				ipv6_key->ipv6_hlimit, is_mask);
 		SW_FLOW_KEY_PUT(match, ip.frag,
 				ipv6_key->ipv6_frag, is_mask);
+		SW_FLOW_KEY_PUT(match, ipv6.exthdrs,
+				ipv6_key->ipv6_exthdr, is_mask);
 		SW_FLOW_KEY_MEMCPY(match, ipv6.addr.src,
 				ipv6_key->ipv6_src,
 				sizeof(match->key->ipv6.addr.src),

@@ -2113,6 +2115,7 @@ static int __ovs_nla_put_key(const struct sw_flow_key *swkey,
 		ipv6_key->ipv6_tclass = output->ip.tos;
 		ipv6_key->ipv6_hlimit = output->ip.ttl;
 		ipv6_key->ipv6_frag = output->ip.frag;
+		ipv6_key->ipv6_exthdr = output->ipv6.exthdrs;
 	} else if (swkey->eth.type == htons(ETH_P_NSH)) {
 		if (nsh_key_to_nlattr(&output->nsh, is_mask, skb))
 			goto nla_put_failure;

base-commit: 5d869070569a23aa909c6e7e9d010fc438a492ef

Signature · 1 line
2.25.1
maintainer
#1 lore raw
Quoted 6 lines · On Thu, 6 May 2021 11:30:53 -0700 Toms Atteka wrote:

+/**
+ * Parses packet and sets IPv6 extension header flags.
+ *

+ * skb          buffer where extension header data starts in packet
+ * nh           ipv6 header
+ * ext_hdrs     flags are stored here

This is not a valid kdoc comment. Please fix.

Quoted 20 lines

+ * OFPIEH12_UNREP is set if more than one of a given IPv6 extension header
+ * is unexpectedly encountered. (Two destination options headers may be
+ * expected and would not cause this bit to be set.)
+ *
+ * OFPIEH12_UNSEQ is set if IPv6 extension headers were not in the order
+ * preferred (but not required) by RFC 2460:
+ *
+ * When more than one extension header is used in the same packet, it is
+ * recommended that those headers appear in the following order:

+ *      IPv6 header
+ *      Hop-by-Hop Options header
+ *      Destination Options header
+ *      Routing header
+ *      Fragment header
+ *      Authentication header
+ *      Encapsulating Security Payload header
+ *      Destination Options header
+ *      upper-layer header

+ */
+static void get_ipv6_ext_hdrs(struct sk_buff *skb, struct ipv6hdr *nh, u16 *ext_hdrs)