selftests_bpf: extend test_tc_tunnel for UDP encap

commit 868d523535c2 ("bpf: add bpf_skb_adjust_room encap flags")
introduced support to bpf_skb_adjust_room for GSO-friendly GRE
and UDP encapsulation and later introduced associated test_tc_tunnel
tests.  Here those tests are extended to cover UDP encapsulation also.

Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

diff --git a/tools/testing/selftests/bpf/config b/tools/testing/selftests/bpf/config
index a42f4fc..8e749c1 100644 (file)
--- a/tools/testing/selftests/bpf/config
+++ b/tools/testing/selftests/bpf/config
@@ -25,3 +25,7 @@ CONFIG_XDP_SOCKETS=y
 CONFIG_FTRACE_SYSCALLS=y
 CONFIG_IPV6_TUNNEL=y
 CONFIG_IPV6_GRE=y
+CONFIG_NET_FOU=m
+CONFIG_NET_FOU_IP_TUNNELS=y
+CONFIG_IPV6_FOU=m
+CONFIG_IPV6_FOU_TUNNEL=m

diff --git a/tools/testing/selftests/bpf/progs/test_tc_tunnel.c b/tools/testing/selftests/bpf/progs/test_tc_tunnel.c
index f541c2d..33b338e 100644 (file)
--- a/tools/testing/selftests/bpf/progs/test_tc_tunnel.c
+++ b/tools/testing/selftests/bpf/progs/test_tc_tunnel.c
@@ -12,6 +12,7 @@
 #include <linux/ip.h>
 #include <linux/ipv6.h>
 #include <linux/tcp.h>
+#include <linux/udp.h>
 #include <linux/pkt_cls.h>
 #include <linux/types.h>
 
@@ -20,16 +21,27 @@
 
 static const int cfg_port = 8000;
 
-struct grev4hdr {
-       struct iphdr ip;
+static const int cfg_udp_src = 20000;
+static const int cfg_udp_dst = 5555;
+
+struct gre_hdr {
        __be16 flags;
        __be16 protocol;
 } __attribute__((packed));
 
-struct grev6hdr {
+union l4hdr {
+       struct udphdr udp;
+       struct gre_hdr gre;
+};
+
+struct v4hdr {
+       struct iphdr ip;
+       union l4hdr l4hdr;
+} __attribute__((packed));
+
+struct v6hdr {
        struct ipv6hdr ip;
-       __be16 flags;
-       __be16 protocol;
+       union l4hdr l4hdr;
 } __attribute__((packed));
 
 static __always_inline void set_ipv4_csum(struct iphdr *iph)
@@ -47,10 +59,10 @@ static __always_inline void set_ipv4_csum(struct iphdr *iph)
        iph->check = ~((csum & 0xffff) + (csum >> 16));
 }
 
-static __always_inline int encap_ipv4(struct __sk_buff *skb, bool with_gre)
+static __always_inline int encap_ipv4(struct __sk_buff *skb, __u8 encap_proto)
 {
-       struct grev4hdr h_outer;
        struct iphdr iph_inner;
+       struct v4hdr h_outer;
        struct tcphdr tcph;
        __u64 flags;
        int olen;
@@ -70,12 +82,29 @@ static __always_inline int encap_ipv4(struct __sk_buff *skb, bool with_gre)
        if (tcph.dest != __bpf_constant_htons(cfg_port))
                return TC_ACT_OK;
 
+       olen = sizeof(h_outer.ip);
+
        flags = BPF_F_ADJ_ROOM_FIXED_GSO | BPF_F_ADJ_ROOM_ENCAP_L3_IPV4;
-       if (with_gre) {
+       switch (encap_proto) {
+       case IPPROTO_GRE:
                flags |= BPF_F_ADJ_ROOM_ENCAP_L4_GRE;
-               olen = sizeof(h_outer);
-       } else {
-               olen = sizeof(h_outer.ip);
+               olen += sizeof(h_outer.l4hdr.gre);
+               h_outer.l4hdr.gre.protocol = bpf_htons(ETH_P_IP);
+               h_outer.l4hdr.gre.flags = 0;
+               break;
+       case IPPROTO_UDP:
+               flags |= BPF_F_ADJ_ROOM_ENCAP_L4_UDP;
+               olen += sizeof(h_outer.l4hdr.udp);
+               h_outer.l4hdr.udp.source = __bpf_constant_htons(cfg_udp_src);
+               h_outer.l4hdr.udp.dest = __bpf_constant_htons(cfg_udp_dst);
+               h_outer.l4hdr.udp.check = 0;
+               h_outer.l4hdr.udp.len = bpf_htons(bpf_ntohs(iph_inner.tot_len) +
+                                                 sizeof(h_outer.l4hdr.udp));
+               break;
+       case IPPROTO_IPIP:
+               break;
+       default:
+               return TC_ACT_OK;
        }
 
        /* add room between mac and network header */
@@ -85,16 +114,10 @@ static __always_inline int encap_ipv4(struct __sk_buff *skb, bool with_gre)
        /* prepare new outer network header */
        h_outer.ip = iph_inner;
        h_outer.ip.tot_len = bpf_htons(olen +
-                                     bpf_htons(h_outer.ip.tot_len));
-       if (with_gre) {
-               h_outer.ip.protocol = IPPROTO_GRE;
-               h_outer.protocol = bpf_htons(ETH_P_IP);
-               h_outer.flags = 0;
-       } else {
-               h_outer.ip.protocol = IPPROTO_IPIP;
-       }
+                                      bpf_ntohs(h_outer.ip.tot_len));
+       h_outer.ip.protocol = encap_proto;
 
-       set_ipv4_csum((void *)&h_outer.ip);
+       set_ipv4_csum(&h_outer.ip);
 
        /* store new outer network header */
        if (bpf_skb_store_bytes(skb, ETH_HLEN, &h_outer, olen,
@@ -104,11 +127,12 @@ static __always_inline int encap_ipv4(struct __sk_buff *skb, bool with_gre)
        return TC_ACT_OK;
 }
 
-static __always_inline int encap_ipv6(struct __sk_buff *skb, bool with_gre)
+static __always_inline int encap_ipv6(struct __sk_buff *skb, __u8 encap_proto)
 {
        struct ipv6hdr iph_inner;
-       struct grev6hdr h_outer;
+       struct v6hdr h_outer;
        struct tcphdr tcph;
+       __u16 tot_len;
        __u64 flags;
        int olen;
 
@@ -124,15 +148,32 @@ static __always_inline int encap_ipv6(struct __sk_buff *skb, bool with_gre)
        if (tcph.dest != __bpf_constant_htons(cfg_port))
                return TC_ACT_OK;
 
+       olen = sizeof(h_outer.ip);
+
        flags = BPF_F_ADJ_ROOM_FIXED_GSO | BPF_F_ADJ_ROOM_ENCAP_L3_IPV6;
-       if (with_gre) {
+       switch (encap_proto) {
+       case IPPROTO_GRE:
                flags |= BPF_F_ADJ_ROOM_ENCAP_L4_GRE;
-               olen = sizeof(h_outer);
-       } else {
-               olen = sizeof(h_outer.ip);
+               olen += sizeof(h_outer.l4hdr.gre);
+               h_outer.l4hdr.gre.protocol = bpf_htons(ETH_P_IPV6);
+               h_outer.l4hdr.gre.flags = 0;
+               break;
+       case IPPROTO_UDP:
+               flags |= BPF_F_ADJ_ROOM_ENCAP_L4_UDP;
+               olen += sizeof(h_outer.l4hdr.udp);
+               h_outer.l4hdr.udp.source = __bpf_constant_htons(cfg_udp_src);
+               h_outer.l4hdr.udp.dest = __bpf_constant_htons(cfg_udp_dst);
+               tot_len = bpf_ntohs(iph_inner.payload_len) + sizeof(iph_inner) +
+                         sizeof(h_outer.l4hdr.udp);
+               h_outer.l4hdr.udp.check = 0;
+               h_outer.l4hdr.udp.len = bpf_htons(tot_len);
+               break;
+       case IPPROTO_IPV6:
+               break;
+       default:
+               return TC_ACT_OK;
        }
 
-
        /* add room between mac and network header */
        if (bpf_skb_adjust_room(skb, olen, BPF_ADJ_ROOM_MAC, flags))
                return TC_ACT_SHOT;
@@ -141,13 +182,8 @@ static __always_inline int encap_ipv6(struct __sk_buff *skb, bool with_gre)
        h_outer.ip = iph_inner;
        h_outer.ip.payload_len = bpf_htons(olen +
                                           bpf_ntohs(h_outer.ip.payload_len));
-       if (with_gre) {
-               h_outer.ip.nexthdr = IPPROTO_GRE;
-               h_outer.protocol = bpf_htons(ETH_P_IPV6);
-               h_outer.flags = 0;
-       } else {
-               h_outer.ip.nexthdr = IPPROTO_IPV6;
-       }
+
+       h_outer.ip.nexthdr = encap_proto;
 
        /* store new outer network header */
        if (bpf_skb_store_bytes(skb, ETH_HLEN, &h_outer, olen,
@@ -161,7 +197,7 @@ SEC("encap_ipip")
 int __encap_ipip(struct __sk_buff *skb)
 {
        if (skb->protocol == __bpf_constant_htons(ETH_P_IP))
-               return encap_ipv4(skb, false);
+               return encap_ipv4(skb, IPPROTO_IPIP);
        else
                return TC_ACT_OK;
 }
@@ -170,7 +206,16 @@ SEC("encap_gre")
 int __encap_gre(struct __sk_buff *skb)
 {
        if (skb->protocol == __bpf_constant_htons(ETH_P_IP))
-               return encap_ipv4(skb, true);
+               return encap_ipv4(skb, IPPROTO_GRE);
+       else
+               return TC_ACT_OK;
+}
+
+SEC("encap_udp")
+int __encap_udp(struct __sk_buff *skb)
+{
+       if (skb->protocol == __bpf_constant_htons(ETH_P_IP))
+               return encap_ipv4(skb, IPPROTO_UDP);
        else
                return TC_ACT_OK;
 }
@@ -179,7 +224,7 @@ SEC("encap_ip6tnl")
 int __encap_ip6tnl(struct __sk_buff *skb)
 {
        if (skb->protocol == __bpf_constant_htons(ETH_P_IPV6))
-               return encap_ipv6(skb, false);
+               return encap_ipv6(skb, IPPROTO_IPV6);
        else
                return TC_ACT_OK;
 }
@@ -188,23 +233,34 @@ SEC("encap_ip6gre")
 int __encap_ip6gre(struct __sk_buff *skb)
 {
        if (skb->protocol == __bpf_constant_htons(ETH_P_IPV6))
-               return encap_ipv6(skb, true);
+               return encap_ipv6(skb, IPPROTO_GRE);
+       else
+               return TC_ACT_OK;
+}
+
+SEC("encap_ip6udp")
+int __encap_ip6udp(struct __sk_buff *skb)
+{
+       if (skb->protocol == __bpf_constant_htons(ETH_P_IPV6))
+               return encap_ipv6(skb, IPPROTO_UDP);
        else
                return TC_ACT_OK;
 }
 
 static int decap_internal(struct __sk_buff *skb, int off, int len, char proto)
 {
-       char buf[sizeof(struct grev6hdr)];
-       int olen;
+       char buf[sizeof(struct v6hdr)];
+       int olen = len;
 
        switch (proto) {
        case IPPROTO_IPIP:
        case IPPROTO_IPV6:
-               olen = len;
                break;
        case IPPROTO_GRE:
-               olen = len + 4 /* gre hdr */;
+               olen += sizeof(struct gre_hdr);
+               break;
+       case IPPROTO_UDP:
+               olen += sizeof(struct udphdr);
                break;
        default:
                return TC_ACT_OK;

diff --git a/tools/testing/selftests/bpf/test_tc_tunnel.sh b/tools/testing/selftests/bpf/test_tc_tunnel.sh
index c805adb..64f3091 100755 (executable)
--- a/tools/testing/selftests/bpf/test_tc_tunnel.sh
+++ b/tools/testing/selftests/bpf/test_tc_tunnel.sh
@@ -15,6 +15,9 @@ readonly ns2_v4=192.168.1.2
 readonly ns1_v6=fd::1
 readonly ns2_v6=fd::2
 
+# Must match port used by bpf program
+readonly udpport=5555
+
 readonly infile="$(mktemp)"
 readonly outfile="$(mktemp)"
 
@@ -38,8 +41,8 @@ setup() {
        # clamp route to reserve room for tunnel headers
        ip -netns "${ns1}" -4 route flush table main
        ip -netns "${ns1}" -6 route flush table main
-       ip -netns "${ns1}" -4 route add "${ns2_v4}" mtu 1476 dev veth1
-       ip -netns "${ns1}" -6 route add "${ns2_v6}" mtu 1456 dev veth1
+       ip -netns "${ns1}" -4 route add "${ns2_v4}" mtu 1472 dev veth1
+       ip -netns "${ns1}" -6 route add "${ns2_v6}" mtu 1452 dev veth1
 
        sleep 1
 
@@ -103,6 +106,18 @@ if [[ "$#" -eq "0" ]]; then
        echo "ip6 gre gso"
        $0 ipv6 ip6gre 2000
 
+       echo "ip udp"
+       $0 ipv4 udp 100
+
+       echo "ip6 udp"
+       $0 ipv6 ip6udp 100
+
+       echo "ip udp gso"
+       $0 ipv4 udp 2000
+
+       echo "ip6 udp gso"
+       $0 ipv6 ip6udp 2000
+
        echo "OK. All tests passed"
        exit 0
 fi
@@ -117,12 +132,20 @@ case "$1" in
 "ipv4")
        readonly addr1="${ns1_v4}"
        readonly addr2="${ns2_v4}"
-       readonly netcat_opt=-4
+       readonly ipproto=4
+       readonly netcat_opt=-${ipproto}
+       readonly foumod=fou
+       readonly foutype=ipip
+       readonly fouproto=4
        ;;
 "ipv6")
        readonly addr1="${ns1_v6}"
        readonly addr2="${ns2_v6}"
-       readonly netcat_opt=-6
+       readonly ipproto=6
+       readonly netcat_opt=-${ipproto}
+       readonly foumod=fou6
+       readonly foutype=ip6tnl
+       readonly fouproto="41 -6"
        ;;
 *)
        echo "unknown arg: $1"
@@ -155,11 +178,23 @@ echo "test bpf encap without decap (expect failure)"
 server_listen
 ! client_connect
 
+if [[ "$tuntype" =~ "udp" ]]; then
+       # Set up fou tunnel.
+       ttype="${foutype}"
+       targs="encap fou encap-sport auto encap-dport $udpport"
+       # fou may be a module; allow this to fail.
+       modprobe "${foumod}" ||true
+       ip netns exec "${ns2}" ip fou add port 5555 ipproto ${fouproto}
+else
+       ttype=$tuntype
+       targs=""
+fi
+
 # serverside, insert decap module
 # server is still running
 # client can connect again
-ip netns exec "${ns2}" ip link add dev testtun0 type "${tuntype}" \
-       remote "${addr1}" local "${addr2}"
+ip netns exec "${ns2}" ip link add name testtun0 type "${ttype}" \
+       remote "${addr1}" local "${addr2}" $targs
 # Because packets are decapped by the tunnel they arrive on testtun0 from
 # the IP stack perspective.  Ensure reverse path filtering is disabled
 # otherwise we drop the TCP SYN as arriving on testtun0 instead of the