From 3ec61df82ba0c2d2455da838ee46bf60f2256b56 Mon Sep 17 00:00:00 2001 From: Alan Maguire Date: Tue, 9 Apr 2019 15:06:43 +0100 Subject: [PATCH] selftests_bpf: add L2 encap to test_tc_tunnel Update test_tc_tunnel to verify adding inner L2 header encapsulation (an MPLS label or ethernet header) works. Signed-off-by: Alan Maguire Signed-off-by: Daniel Borkmann --- tools/testing/selftests/bpf/config | 4 + .../selftests/bpf/progs/test_tc_tunnel.c | 219 +++++++++++++++--- tools/testing/selftests/bpf/test_tc_tunnel.sh | 113 ++++++--- 3 files changed, 277 insertions(+), 59 deletions(-) diff --git a/tools/testing/selftests/bpf/config b/tools/testing/selftests/bpf/config index 8e749c1f5bf6..8c976476f6fd 100644 --- a/tools/testing/selftests/bpf/config +++ b/tools/testing/selftests/bpf/config @@ -29,3 +29,7 @@ CONFIG_NET_FOU=m CONFIG_NET_FOU_IP_TUNNELS=y CONFIG_IPV6_FOU=m CONFIG_IPV6_FOU_TUNNEL=m +CONFIG_MPLS=y +CONFIG_NET_MPLS_GSO=m +CONFIG_MPLS_ROUTING=m +CONFIG_MPLS_IPTUNNEL=m diff --git a/tools/testing/selftests/bpf/progs/test_tc_tunnel.c b/tools/testing/selftests/bpf/progs/test_tc_tunnel.c index 33b338e6cf09..bcb00d737e95 100644 --- a/tools/testing/selftests/bpf/progs/test_tc_tunnel.c +++ b/tools/testing/selftests/bpf/progs/test_tc_tunnel.c @@ -11,6 +11,7 @@ #include #include #include +#include #include #include #include @@ -22,7 +23,14 @@ static const int cfg_port = 8000; static const int cfg_udp_src = 20000; -static const int cfg_udp_dst = 5555; + +#define UDP_PORT 5555 +#define MPLS_OVER_UDP_PORT 6635 +#define ETH_OVER_UDP_PORT 7777 + +/* MPLS label 1000 with S bit (last label) set and ttl of 255. */ +static const __u32 mpls_label = __bpf_constant_htonl(1000 << 12 | + MPLS_LS_S_MASK | 0xff); struct gre_hdr { __be16 flags; @@ -37,11 +45,13 @@ union l4hdr { struct v4hdr { struct iphdr ip; union l4hdr l4hdr; + __u8 pad[16]; /* enough space for L2 header */ } __attribute__((packed)); struct v6hdr { struct ipv6hdr ip; union l4hdr l4hdr; + __u8 pad[16]; /* enough space for L2 header */ } __attribute__((packed)); static __always_inline void set_ipv4_csum(struct iphdr *iph) @@ -59,13 +69,15 @@ 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, __u8 encap_proto) +static __always_inline int encap_ipv4(struct __sk_buff *skb, __u8 encap_proto, + __u16 l2_proto) { + __u16 udp_dst = UDP_PORT; struct iphdr iph_inner; struct v4hdr h_outer; struct tcphdr tcph; + int olen, l2_len; __u64 flags; - int olen; if (bpf_skb_load_bytes(skb, ETH_HLEN, &iph_inner, sizeof(iph_inner)) < 0) @@ -83,23 +95,38 @@ static __always_inline int encap_ipv4(struct __sk_buff *skb, __u8 encap_proto) return TC_ACT_OK; olen = sizeof(h_outer.ip); + l2_len = 0; flags = BPF_F_ADJ_ROOM_FIXED_GSO | BPF_F_ADJ_ROOM_ENCAP_L3_IPV4; + + switch (l2_proto) { + case ETH_P_MPLS_UC: + l2_len = sizeof(mpls_label); + udp_dst = MPLS_OVER_UDP_PORT; + break; + case ETH_P_TEB: + l2_len = ETH_HLEN; + udp_dst = ETH_OVER_UDP_PORT; + break; + } + flags |= BPF_F_ADJ_ROOM_ENCAP_L2(l2_len); + switch (encap_proto) { case IPPROTO_GRE: flags |= BPF_F_ADJ_ROOM_ENCAP_L4_GRE; olen += sizeof(h_outer.l4hdr.gre); - h_outer.l4hdr.gre.protocol = bpf_htons(ETH_P_IP); + h_outer.l4hdr.gre.protocol = bpf_htons(l2_proto); 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.dest = bpf_htons(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)); + sizeof(h_outer.l4hdr.udp) + + l2_len); break; case IPPROTO_IPIP: break; @@ -107,6 +134,19 @@ static __always_inline int encap_ipv4(struct __sk_buff *skb, __u8 encap_proto) return TC_ACT_OK; } + /* add L2 encap (if specified) */ + switch (l2_proto) { + case ETH_P_MPLS_UC: + *((__u32 *)((__u8 *)&h_outer + olen)) = mpls_label; + break; + case ETH_P_TEB: + if (bpf_skb_load_bytes(skb, 0, (__u8 *)&h_outer + olen, + ETH_HLEN)) + return TC_ACT_SHOT; + break; + } + olen += l2_len; + /* add room between mac and network header */ if (bpf_skb_adjust_room(skb, olen, BPF_ADJ_ROOM_MAC, flags)) return TC_ACT_SHOT; @@ -127,14 +167,16 @@ static __always_inline int encap_ipv4(struct __sk_buff *skb, __u8 encap_proto) return TC_ACT_OK; } -static __always_inline int encap_ipv6(struct __sk_buff *skb, __u8 encap_proto) +static __always_inline int encap_ipv6(struct __sk_buff *skb, __u8 encap_proto, + __u16 l2_proto) { + __u16 udp_dst = UDP_PORT; struct ipv6hdr iph_inner; struct v6hdr h_outer; struct tcphdr tcph; + int olen, l2_len; __u16 tot_len; __u64 flags; - int olen; if (bpf_skb_load_bytes(skb, ETH_HLEN, &iph_inner, sizeof(iph_inner)) < 0) @@ -149,20 +191,34 @@ static __always_inline int encap_ipv6(struct __sk_buff *skb, __u8 encap_proto) return TC_ACT_OK; olen = sizeof(h_outer.ip); + l2_len = 0; flags = BPF_F_ADJ_ROOM_FIXED_GSO | BPF_F_ADJ_ROOM_ENCAP_L3_IPV6; + + switch (l2_proto) { + case ETH_P_MPLS_UC: + l2_len = sizeof(mpls_label); + udp_dst = MPLS_OVER_UDP_PORT; + break; + case ETH_P_TEB: + l2_len = ETH_HLEN; + udp_dst = ETH_OVER_UDP_PORT; + break; + } + flags |= BPF_F_ADJ_ROOM_ENCAP_L2(l2_len); + switch (encap_proto) { case IPPROTO_GRE: flags |= BPF_F_ADJ_ROOM_ENCAP_L4_GRE; olen += sizeof(h_outer.l4hdr.gre); - h_outer.l4hdr.gre.protocol = bpf_htons(ETH_P_IPV6); + h_outer.l4hdr.gre.protocol = bpf_htons(l2_proto); 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.dest = bpf_htons(udp_dst); tot_len = bpf_ntohs(iph_inner.payload_len) + sizeof(iph_inner) + sizeof(h_outer.l4hdr.udp); h_outer.l4hdr.udp.check = 0; @@ -174,6 +230,19 @@ static __always_inline int encap_ipv6(struct __sk_buff *skb, __u8 encap_proto) return TC_ACT_OK; } + /* add L2 encap (if specified) */ + switch (l2_proto) { + case ETH_P_MPLS_UC: + *((__u32 *)((__u8 *)&h_outer + olen)) = mpls_label; + break; + case ETH_P_TEB: + if (bpf_skb_load_bytes(skb, 0, (__u8 *)&h_outer + olen, + ETH_HLEN)) + return TC_ACT_SHOT; + break; + } + olen += l2_len; + /* add room between mac and network header */ if (bpf_skb_adjust_room(skb, olen, BPF_ADJ_ROOM_MAC, flags)) return TC_ACT_SHOT; @@ -193,56 +262,128 @@ static __always_inline int encap_ipv6(struct __sk_buff *skb, __u8 encap_proto) return TC_ACT_OK; } -SEC("encap_ipip") -int __encap_ipip(struct __sk_buff *skb) +SEC("encap_ipip_none") +int __encap_ipip_none(struct __sk_buff *skb) +{ + if (skb->protocol == __bpf_constant_htons(ETH_P_IP)) + return encap_ipv4(skb, IPPROTO_IPIP, ETH_P_IP); + else + return TC_ACT_OK; +} + +SEC("encap_gre_none") +int __encap_gre_none(struct __sk_buff *skb) +{ + if (skb->protocol == __bpf_constant_htons(ETH_P_IP)) + return encap_ipv4(skb, IPPROTO_GRE, ETH_P_IP); + else + return TC_ACT_OK; +} + +SEC("encap_gre_mpls") +int __encap_gre_mpls(struct __sk_buff *skb) +{ + if (skb->protocol == __bpf_constant_htons(ETH_P_IP)) + return encap_ipv4(skb, IPPROTO_GRE, ETH_P_MPLS_UC); + else + return TC_ACT_OK; +} + +SEC("encap_gre_eth") +int __encap_gre_eth(struct __sk_buff *skb) { if (skb->protocol == __bpf_constant_htons(ETH_P_IP)) - return encap_ipv4(skb, IPPROTO_IPIP); + return encap_ipv4(skb, IPPROTO_GRE, ETH_P_TEB); else return TC_ACT_OK; } -SEC("encap_gre") -int __encap_gre(struct __sk_buff *skb) +SEC("encap_udp_none") +int __encap_udp_none(struct __sk_buff *skb) { if (skb->protocol == __bpf_constant_htons(ETH_P_IP)) - return encap_ipv4(skb, IPPROTO_GRE); + return encap_ipv4(skb, IPPROTO_UDP, ETH_P_IP); else return TC_ACT_OK; } -SEC("encap_udp") -int __encap_udp(struct __sk_buff *skb) +SEC("encap_udp_mpls") +int __encap_udp_mpls(struct __sk_buff *skb) { if (skb->protocol == __bpf_constant_htons(ETH_P_IP)) - return encap_ipv4(skb, IPPROTO_UDP); + return encap_ipv4(skb, IPPROTO_UDP, ETH_P_MPLS_UC); + else + return TC_ACT_OK; +} + +SEC("encap_udp_eth") +int __encap_udp_eth(struct __sk_buff *skb) +{ + if (skb->protocol == __bpf_constant_htons(ETH_P_IP)) + return encap_ipv4(skb, IPPROTO_UDP, ETH_P_TEB); + else + return TC_ACT_OK; +} + +SEC("encap_ip6tnl_none") +int __encap_ip6tnl_none(struct __sk_buff *skb) +{ + if (skb->protocol == __bpf_constant_htons(ETH_P_IPV6)) + return encap_ipv6(skb, IPPROTO_IPV6, ETH_P_IPV6); + else + return TC_ACT_OK; +} + +SEC("encap_ip6gre_none") +int __encap_ip6gre_none(struct __sk_buff *skb) +{ + if (skb->protocol == __bpf_constant_htons(ETH_P_IPV6)) + return encap_ipv6(skb, IPPROTO_GRE, ETH_P_IPV6); + else + return TC_ACT_OK; +} + +SEC("encap_ip6gre_mpls") +int __encap_ip6gre_mpls(struct __sk_buff *skb) +{ + if (skb->protocol == __bpf_constant_htons(ETH_P_IPV6)) + return encap_ipv6(skb, IPPROTO_GRE, ETH_P_MPLS_UC); + else + return TC_ACT_OK; +} + +SEC("encap_ip6gre_eth") +int __encap_ip6gre_eth(struct __sk_buff *skb) +{ + if (skb->protocol == __bpf_constant_htons(ETH_P_IPV6)) + return encap_ipv6(skb, IPPROTO_GRE, ETH_P_TEB); else return TC_ACT_OK; } -SEC("encap_ip6tnl") -int __encap_ip6tnl(struct __sk_buff *skb) +SEC("encap_ip6udp_none") +int __encap_ip6udp_none(struct __sk_buff *skb) { if (skb->protocol == __bpf_constant_htons(ETH_P_IPV6)) - return encap_ipv6(skb, IPPROTO_IPV6); + return encap_ipv6(skb, IPPROTO_UDP, ETH_P_IPV6); else return TC_ACT_OK; } -SEC("encap_ip6gre") -int __encap_ip6gre(struct __sk_buff *skb) +SEC("encap_ip6udp_mpls") +int __encap_ip6udp_mpls(struct __sk_buff *skb) { if (skb->protocol == __bpf_constant_htons(ETH_P_IPV6)) - return encap_ipv6(skb, IPPROTO_GRE); + return encap_ipv6(skb, IPPROTO_UDP, ETH_P_MPLS_UC); else return TC_ACT_OK; } -SEC("encap_ip6udp") -int __encap_ip6udp(struct __sk_buff *skb) +SEC("encap_ip6udp_eth") +int __encap_ip6udp_eth(struct __sk_buff *skb) { if (skb->protocol == __bpf_constant_htons(ETH_P_IPV6)) - return encap_ipv6(skb, IPPROTO_UDP); + return encap_ipv6(skb, IPPROTO_UDP, ETH_P_TEB); else return TC_ACT_OK; } @@ -250,6 +391,8 @@ int __encap_ip6udp(struct __sk_buff *skb) static int decap_internal(struct __sk_buff *skb, int off, int len, char proto) { char buf[sizeof(struct v6hdr)]; + struct gre_hdr greh; + struct udphdr udph; int olen = len; switch (proto) { @@ -258,9 +401,29 @@ static int decap_internal(struct __sk_buff *skb, int off, int len, char proto) break; case IPPROTO_GRE: olen += sizeof(struct gre_hdr); + if (bpf_skb_load_bytes(skb, off + len, &greh, sizeof(greh)) < 0) + return TC_ACT_OK; + switch (bpf_ntohs(greh.protocol)) { + case ETH_P_MPLS_UC: + olen += sizeof(mpls_label); + break; + case ETH_P_TEB: + olen += ETH_HLEN; + break; + } break; case IPPROTO_UDP: olen += sizeof(struct udphdr); + if (bpf_skb_load_bytes(skb, off + len, &udph, sizeof(udph)) < 0) + return TC_ACT_OK; + switch (bpf_ntohs(udph.dest)) { + case MPLS_OVER_UDP_PORT: + olen += sizeof(mpls_label); + break; + case ETH_OVER_UDP_PORT: + olen += ETH_HLEN; + break; + } 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 64f30910d39a..d4d8d5d3b06e 100755 --- a/tools/testing/selftests/bpf/test_tc_tunnel.sh +++ b/tools/testing/selftests/bpf/test_tc_tunnel.sh @@ -17,6 +17,9 @@ readonly ns2_v6=fd::2 # Must match port used by bpf program readonly udpport=5555 +# MPLSoverUDP +readonly mplsudpport=6635 +readonly mplsproto=137 readonly infile="$(mktemp)" readonly outfile="$(mktemp)" @@ -41,8 +44,8 @@ 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 1472 dev veth1 - ip -netns "${ns1}" -6 route add "${ns2_v6}" mtu 1452 dev veth1 + ip -netns "${ns1}" -4 route add "${ns2_v4}" mtu 1458 dev veth1 + ip -netns "${ns1}" -6 route add "${ns2_v6}" mtu 1438 dev veth1 sleep 1 @@ -89,42 +92,44 @@ set -e # no arguments: automated test, run all if [[ "$#" -eq "0" ]]; then echo "ipip" - $0 ipv4 ipip 100 + $0 ipv4 ipip none 100 echo "ip6ip6" - $0 ipv6 ip6tnl 100 + $0 ipv6 ip6tnl none 100 - echo "ip gre" - $0 ipv4 gre 100 + for mac in none mpls eth ; do + echo "ip gre $mac" + $0 ipv4 gre $mac 100 - echo "ip6 gre" - $0 ipv6 ip6gre 100 + echo "ip6 gre $mac" + $0 ipv6 ip6gre $mac 100 - echo "ip gre gso" - $0 ipv4 gre 2000 + echo "ip gre $mac gso" + $0 ipv4 gre $mac 2000 - echo "ip6 gre gso" - $0 ipv6 ip6gre 2000 + echo "ip6 gre $mac gso" + $0 ipv6 ip6gre $mac 2000 - echo "ip udp" - $0 ipv4 udp 100 + echo "ip udp $mac" + $0 ipv4 udp $mac 100 - echo "ip6 udp" - $0 ipv6 ip6udp 100 + echo "ip6 udp $mac" + $0 ipv6 ip6udp $mac 100 - echo "ip udp gso" - $0 ipv4 udp 2000 + echo "ip udp $mac gso" + $0 ipv4 udp $mac 2000 - echo "ip6 udp gso" - $0 ipv6 ip6udp 2000 + echo "ip6 udp $mac gso" + $0 ipv6 ip6udp $mac 2000 + done echo "OK. All tests passed" exit 0 fi -if [[ "$#" -ne "3" ]]; then +if [[ "$#" -ne "4" ]]; then echo "Usage: $0" - echo " or: $0 " + echo " or: $0 " exit 1 fi @@ -137,6 +142,8 @@ case "$1" in readonly foumod=fou readonly foutype=ipip readonly fouproto=4 + readonly fouproto_mpls=${mplsproto} + readonly gretaptype=gretap ;; "ipv6") readonly addr1="${ns1_v6}" @@ -146,6 +153,8 @@ case "$1" in readonly foumod=fou6 readonly foutype=ip6tnl readonly fouproto="41 -6" + readonly fouproto_mpls="${mplsproto} -6" + readonly gretaptype=ip6gretap ;; *) echo "unknown arg: $1" @@ -154,9 +163,10 @@ case "$1" in esac readonly tuntype=$2 -readonly datalen=$3 +readonly mac=$3 +readonly datalen=$4 -echo "encap ${addr1} to ${addr2}, type ${tuntype}, len ${datalen}" +echo "encap ${addr1} to ${addr2}, type ${tuntype}, mac ${mac} len ${datalen}" trap cleanup EXIT @@ -173,7 +183,7 @@ verify_data ip netns exec "${ns1}" tc qdisc add dev veth1 clsact ip netns exec "${ns1}" tc filter add dev veth1 egress \ bpf direct-action object-file ./test_tc_tunnel.o \ - section "encap_${tuntype}" + section "encap_${tuntype}_${mac}" echo "test bpf encap without decap (expect failure)" server_listen ! client_connect @@ -184,7 +194,18 @@ if [[ "$tuntype" =~ "udp" ]]; then 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 ${fouproto} + if [[ "$mac" == "mpls" ]]; then + dport=${mplsudpport} + dproto=${fouproto_mpls} + tmode="mode any ttl 255" + else + dport=${udpport} + dproto=${fouproto} + fi + ip netns exec "${ns2}" ip fou add port $dport ipproto ${dproto} + targs="encap fou encap-sport auto encap-dport $dport" +elif [[ "$tuntype" =~ "gre" && "$mac" == "eth" ]]; then + ttype=$gretaptype else ttype=$tuntype targs="" @@ -194,7 +215,31 @@ fi # server is still running # client can connect again ip netns exec "${ns2}" ip link add name testtun0 type "${ttype}" \ - remote "${addr1}" local "${addr2}" $targs + ${tmode} remote "${addr1}" local "${addr2}" $targs + +expect_tun_fail=0 + +if [[ "$tuntype" == "ip6udp" && "$mac" == "mpls" ]]; then + # No support for MPLS IPv6 fou tunnel; expect failure. + expect_tun_fail=1 +elif [[ "$tuntype" =~ "udp" && "$mac" == "eth" ]]; then + # No support for TEB fou tunnel; expect failure. + expect_tun_fail=1 +elif [[ "$tuntype" =~ "gre" && "$mac" == "eth" ]]; then + # Share ethernet address between tunnel/veth2 so L2 decap works. + ethaddr=$(ip netns exec "${ns2}" ip link show veth2 | \ + awk '/ether/ { print $2 }') + ip netns exec "${ns2}" ip link set testtun0 address $ethaddr +elif [[ "$mac" == "mpls" ]]; then + modprobe mpls_iptunnel ||true + modprobe mpls_gso ||true + ip netns exec "${ns2}" sysctl -qw net.mpls.platform_labels=65536 + ip netns exec "${ns2}" ip -f mpls route add 1000 dev lo + ip netns exec "${ns2}" ip link set lo up + ip netns exec "${ns2}" sysctl -qw net.mpls.conf.testtun0.input=1 + ip netns exec "${ns2}" sysctl -qw net.ipv4.conf.lo.rp_filter=0 +fi + # Because packets are decapped by the tunnel they arrive on testtun0 from # the IP stack perspective. Ensure reverse path filtering is disabled # otherwise we drop the TCP SYN as arriving on testtun0 instead of the @@ -204,16 +249,22 @@ ip netns exec "${ns2}" sysctl -qw net.ipv4.conf.all.rp_filter=0 # selected as the max of the "all" and device-specific values. ip netns exec "${ns2}" sysctl -qw net.ipv4.conf.testtun0.rp_filter=0 ip netns exec "${ns2}" ip link set dev testtun0 up -echo "test bpf encap with tunnel device decap" -client_connect -verify_data +if [[ "$expect_tun_fail" == 1 ]]; then + # This tunnel mode is not supported, so we expect failure. + echo "test bpf encap with tunnel device decap (expect failure)" + ! client_connect +else + echo "test bpf encap with tunnel device decap" + client_connect + verify_data + server_listen +fi # serverside, use BPF for decap ip netns exec "${ns2}" ip link del dev testtun0 ip netns exec "${ns2}" tc qdisc add dev veth2 clsact ip netns exec "${ns2}" tc filter add dev veth2 ingress \ bpf direct-action object-file ./test_tc_tunnel.o section decap -server_listen echo "test bpf encap with bpf decap" client_connect verify_data -- 2.30.2