openvswitch: Add SCTP support

This patch adds support for rewriting SCTP src,dst ports similar to the
functionality already available for TCP/UDP.

Rewriting SCTP ports is expensive due to double-recalculation of the
SCTP checksums; this is performed to ensure that packets traversing OVS
with invalid checksums will continue to the destination with any
checksum corruption intact.

Reviewed-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Joe Stringer <joe@wand.net.nz>
Signed-off-by: Ben Pfaff <blp@nicira.com>
Signed-off-by: Jesse Gross <jesse@nicira.com>

diff --git a/include/uapi/linux/openvswitch.h b/include/uapi/linux/openvswitch.h
index de1fa5d..a74d375 100644 (file)
--- a/include/uapi/linux/openvswitch.h
+++ b/include/uapi/linux/openvswitch.h
@@ -259,6 +259,7 @@ enum ovs_key_attr {
        OVS_KEY_ATTR_ND,        /* struct ovs_key_nd */
        OVS_KEY_ATTR_SKB_MARK,  /* u32 skb mark */
        OVS_KEY_ATTR_TUNNEL,    /* Nested set of ovs_tunnel attributes */
+       OVS_KEY_ATTR_SCTP,      /* struct ovs_key_sctp */
 
 #ifdef __KERNEL__
        OVS_KEY_ATTR_IPV4_TUNNEL,  /* struct ovs_key_ipv4_tunnel */
@@ -333,6 +334,11 @@ struct ovs_key_udp {
        __be16 udp_dst;
 };
 
+struct ovs_key_sctp {
+       __be16 sctp_src;
+       __be16 sctp_dst;
+};
+
 struct ovs_key_icmp {
        __u8 icmp_type;
        __u8 icmp_code;

diff --git a/net/openvswitch/Kconfig b/net/openvswitch/Kconfig
index bed30e6..6ecf491 100644 (file)
--- a/net/openvswitch/Kconfig
+++ b/net/openvswitch/Kconfig
@@ -4,6 +4,7 @@
 
 config OPENVSWITCH
        tristate "Open vSwitch"
+       select LIBCRC32C
        ---help---
          Open vSwitch is a multilayer Ethernet switch targeted at virtualized
          environments.  In addition to supporting a variety of features

diff --git a/net/openvswitch/actions.c b/net/openvswitch/actions.c
index 1f68022..65cfaa8 100644 (file)
--- a/net/openvswitch/actions.c
+++ b/net/openvswitch/actions.c
@@ -22,6 +22,7 @@
 #include <linux/in.h>
 #include <linux/ip.h>
 #include <linux/openvswitch.h>
+#include <linux/sctp.h>
 #include <linux/tcp.h>
 #include <linux/udp.h>
 #include <linux/in6.h>
@@ -31,6 +32,7 @@
 #include <net/ipv6.h>
 #include <net/checksum.h>
 #include <net/dsfield.h>
+#include <net/sctp/checksum.h>
 
 #include "datapath.h"
 #include "vport.h"
@@ -352,6 +354,39 @@ static int set_tcp(struct sk_buff *skb, const struct ovs_key_tcp *tcp_port_key)
        return 0;
 }
 
+static int set_sctp(struct sk_buff *skb,
+                    const struct ovs_key_sctp *sctp_port_key)
+{
+       struct sctphdr *sh;
+       int err;
+       unsigned int sctphoff = skb_transport_offset(skb);
+
+       err = make_writable(skb, sctphoff + sizeof(struct sctphdr));
+       if (unlikely(err))
+               return err;
+
+       sh = sctp_hdr(skb);
+       if (sctp_port_key->sctp_src != sh->source ||
+           sctp_port_key->sctp_dst != sh->dest) {
+               __le32 old_correct_csum, new_csum, old_csum;
+
+               old_csum = sh->checksum;
+               old_correct_csum = sctp_compute_cksum(skb, sctphoff);
+
+               sh->source = sctp_port_key->sctp_src;
+               sh->dest = sctp_port_key->sctp_dst;
+
+               new_csum = sctp_compute_cksum(skb, sctphoff);
+
+               /* Carry any checksum errors through. */
+               sh->checksum = old_csum ^ old_correct_csum ^ new_csum;
+
+               skb->rxhash = 0;
+       }
+
+       return 0;
+}
+
 static int do_output(struct datapath *dp, struct sk_buff *skb, int out_port)
 {
        struct vport *vport;
@@ -461,6 +496,10 @@ static int execute_set_action(struct sk_buff *skb,
        case OVS_KEY_ATTR_UDP:
                err = set_udp(skb, nla_data(nested_attr));
                break;
+
+       case OVS_KEY_ATTR_SCTP:
+               err = set_sctp(skb, nla_data(nested_attr));
+               break;
        }
 
        return err;

diff --git a/net/openvswitch/datapath.c b/net/openvswitch/datapath.c
index d29cd9a..2aa13bd 100644 (file)
--- a/net/openvswitch/datapath.c
+++ b/net/openvswitch/datapath.c
@@ -712,6 +712,12 @@ static int validate_set(const struct nlattr *a,
 
                return validate_tp_port(flow_key);
 
+       case OVS_KEY_ATTR_SCTP:
+               if (flow_key->ip.proto != IPPROTO_SCTP)
+                       return -EINVAL;
+
+               return validate_tp_port(flow_key);
+
        default:
                return -EINVAL;
        }

diff --git a/net/openvswitch/flow.c b/net/openvswitch/flow.c
index 1fceb96..2b47855 100644 (file)
--- a/net/openvswitch/flow.c
+++ b/net/openvswitch/flow.c
@@ -34,6 +34,7 @@
 #include <linux/if_arp.h>
 #include <linux/ip.h>
 #include <linux/ipv6.h>
+#include <linux/sctp.h>
 #include <linux/tcp.h>
 #include <linux/udp.h>
 #include <linux/icmp.h>
@@ -129,6 +130,7 @@ static bool ovs_match_validate(const struct sw_flow_match *match,
                        | (1 << OVS_KEY_ATTR_IPV6)
                        | (1 << OVS_KEY_ATTR_TCP)
                        | (1 << OVS_KEY_ATTR_UDP)
+                       | (1 << OVS_KEY_ATTR_SCTP)
                        | (1 << OVS_KEY_ATTR_ICMP)
                        | (1 << OVS_KEY_ATTR_ICMPV6)
                        | (1 << OVS_KEY_ATTR_ARP)
@@ -159,6 +161,12 @@ static bool ovs_match_validate(const struct sw_flow_match *match,
                                        mask_allowed |= 1 << OVS_KEY_ATTR_UDP;
                        }
 
+                       if (match->key->ip.proto == IPPROTO_SCTP) {
+                               key_expected |= 1 << OVS_KEY_ATTR_SCTP;
+                               if (match->mask && (match->mask->key.ip.proto == 0xff))
+                                       mask_allowed |= 1 << OVS_KEY_ATTR_SCTP;
+                       }
+
                        if (match->key->ip.proto == IPPROTO_TCP) {
                                key_expected |= 1 << OVS_KEY_ATTR_TCP;
                                if (match->mask && (match->mask->key.ip.proto == 0xff))
@@ -185,6 +193,12 @@ static bool ovs_match_validate(const struct sw_flow_match *match,
                                        mask_allowed |= 1 << OVS_KEY_ATTR_UDP;
                        }
 
+                       if (match->key->ip.proto == IPPROTO_SCTP) {
+                               key_expected |= 1 << OVS_KEY_ATTR_SCTP;
+                               if (match->mask && (match->mask->key.ip.proto == 0xff))
+                                       mask_allowed |= 1 << OVS_KEY_ATTR_SCTP;
+                       }
+
                        if (match->key->ip.proto == IPPROTO_TCP) {
                                key_expected |= 1 << OVS_KEY_ATTR_TCP;
                                if (match->mask && (match->mask->key.ip.proto == 0xff))
@@ -280,6 +294,12 @@ static bool udphdr_ok(struct sk_buff *skb)
                                  sizeof(struct udphdr));
 }
 
+static bool sctphdr_ok(struct sk_buff *skb)
+{
+       return pskb_may_pull(skb, skb_transport_offset(skb) +
+                                 sizeof(struct sctphdr));
+}
+
 static bool icmphdr_ok(struct sk_buff *skb)
 {
        return pskb_may_pull(skb, skb_transport_offset(skb) +
@@ -891,6 +911,12 @@ int ovs_flow_extract(struct sk_buff *skb, u16 in_port, struct sw_flow_key *key)
                                key->ipv4.tp.src = udp->source;
                                key->ipv4.tp.dst = udp->dest;
                        }
+               } else if (key->ip.proto == IPPROTO_SCTP) {
+                       if (sctphdr_ok(skb)) {
+                               struct sctphdr *sctp = sctp_hdr(skb);
+                               key->ipv4.tp.src = sctp->source;
+                               key->ipv4.tp.dst = sctp->dest;
+                       }
                } else if (key->ip.proto == IPPROTO_ICMP) {
                        if (icmphdr_ok(skb)) {
                                struct icmphdr *icmp = icmp_hdr(skb);
@@ -953,6 +979,12 @@ int ovs_flow_extract(struct sk_buff *skb, u16 in_port, struct sw_flow_key *key)
                                key->ipv6.tp.src = udp->source;
                                key->ipv6.tp.dst = udp->dest;
                        }
+               } else if (key->ip.proto == NEXTHDR_SCTP) {
+                       if (sctphdr_ok(skb)) {
+                               struct sctphdr *sctp = sctp_hdr(skb);
+                               key->ipv6.tp.src = sctp->source;
+                               key->ipv6.tp.dst = sctp->dest;
+                       }
                } else if (key->ip.proto == NEXTHDR_ICMP) {
                        if (icmp6hdr_ok(skb)) {
                                error = parse_icmpv6(skb, key, nh_len);
@@ -1087,6 +1119,7 @@ const int ovs_key_lens[OVS_KEY_ATTR_MAX + 1] = {
        [OVS_KEY_ATTR_IPV6] = sizeof(struct ovs_key_ipv6),
        [OVS_KEY_ATTR_TCP] = sizeof(struct ovs_key_tcp),
        [OVS_KEY_ATTR_UDP] = sizeof(struct ovs_key_udp),
+       [OVS_KEY_ATTR_SCTP] = sizeof(struct ovs_key_sctp),
        [OVS_KEY_ATTR_ICMP] = sizeof(struct ovs_key_icmp),
        [OVS_KEY_ATTR_ICMPV6] = sizeof(struct ovs_key_icmpv6),
        [OVS_KEY_ATTR_ARP] = sizeof(struct ovs_key_arp),
@@ -1500,6 +1533,24 @@ static int ovs_key_from_nlattrs(struct sw_flow_match *match,  u64 attrs,
                attrs &= ~(1 << OVS_KEY_ATTR_UDP);
        }
 
+       if (attrs & (1 << OVS_KEY_ATTR_SCTP)) {
+               const struct ovs_key_sctp *sctp_key;
+
+               sctp_key = nla_data(a[OVS_KEY_ATTR_SCTP]);
+               if (orig_attrs & (1 << OVS_KEY_ATTR_IPV4)) {
+                       SW_FLOW_KEY_PUT(match, ipv4.tp.src,
+                                       sctp_key->sctp_src, is_mask);
+                       SW_FLOW_KEY_PUT(match, ipv4.tp.dst,
+                                       sctp_key->sctp_dst, is_mask);
+               } else {
+                       SW_FLOW_KEY_PUT(match, ipv6.tp.src,
+                                       sctp_key->sctp_src, is_mask);
+                       SW_FLOW_KEY_PUT(match, ipv6.tp.dst,
+                                       sctp_key->sctp_dst, is_mask);
+               }
+               attrs &= ~(1 << OVS_KEY_ATTR_SCTP);
+       }
+
        if (attrs & (1 << OVS_KEY_ATTR_ICMP)) {
                const struct ovs_key_icmp *icmp_key;
 
@@ -1843,6 +1894,20 @@ int ovs_flow_to_nlattrs(const struct sw_flow_key *swkey,
                                udp_key->udp_src = output->ipv6.tp.src;
                                udp_key->udp_dst = output->ipv6.tp.dst;
                        }
+               } else if (swkey->ip.proto == IPPROTO_SCTP) {
+                       struct ovs_key_sctp *sctp_key;
+
+                       nla = nla_reserve(skb, OVS_KEY_ATTR_SCTP, sizeof(*sctp_key));
+                       if (!nla)
+                               goto nla_put_failure;
+                       sctp_key = nla_data(nla);
+                       if (swkey->eth.type == htons(ETH_P_IP)) {
+                               sctp_key->sctp_src = swkey->ipv4.tp.src;
+                               sctp_key->sctp_dst = swkey->ipv4.tp.dst;
+                       } else if (swkey->eth.type == htons(ETH_P_IPV6)) {
+                               sctp_key->sctp_src = swkey->ipv6.tp.src;
+                               sctp_key->sctp_dst = swkey->ipv6.tp.dst;
+                       }
                } else if (swkey->eth.type == htons(ETH_P_IP) &&
                           swkey->ip.proto == IPPROTO_ICMP) {
                        struct ovs_key_icmp *icmp_key;

diff --git a/net/openvswitch/flow.h b/net/openvswitch/flow.h
index 9674e45..d08dcf7 100644 (file)
--- a/net/openvswitch/flow.h
+++ b/net/openvswitch/flow.h
@@ -99,8 +99,8 @@ struct sw_flow_key {
                        } addr;
                        union {
                                struct {
-                                       __be16 src;             /* TCP/UDP source port. */
-                                       __be16 dst;             /* TCP/UDP destination port. */
+                                       __be16 src;             /* TCP/UDP/SCTP source port. */
+                                       __be16 dst;             /* TCP/UDP/SCTP destination port. */
                                } tp;
                                struct {
                                        u8 sha[ETH_ALEN];       /* ARP source hardware address. */
@@ -115,8 +115,8 @@ struct sw_flow_key {
                        } addr;
                        __be32 label;                   /* IPv6 flow label. */
                        struct {
-                               __be16 src;             /* TCP/UDP source port. */
-                               __be16 dst;             /* TCP/UDP destination port. */
+                               __be16 src;             /* TCP/UDP/SCTP source port. */
+                               __be16 dst;             /* TCP/UDP/SCTP destination port. */
                        } tp;
                        struct {
                                struct in6_addr target; /* ND target address. */