diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile index 66897e61232cbfdd3129c6bd8331af8eca229d1e..0bf2478cb7dfeed534a5fad022adc86c866b0c39 100644 --- a/samples/bpf/Makefile +++ b/samples/bpf/Makefile @@ -60,6 +60,7 @@ always += spintest_kern.o always += map_perf_test_kern.o always += test_overhead_tp_kern.o always += test_overhead_kprobe_kern.o +always += parse_varlen.o parse_simple.o parse_ldabs.o HOSTCFLAGS += -I$(objtree)/usr/include @@ -120,4 +121,5 @@ $(src)/*.c: verify_target_bpf $(obj)/%.o: $(src)/%.c $(CLANG) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) $(EXTRA_CFLAGS) \ -D__KERNEL__ -D__ASM_SYSREG_H -Wno-unused-value -Wno-pointer-sign \ + -Wno-compare-distinct-pointer-types \ -O2 -emit-llvm -c $< -o -| $(LLC) -march=bpf -filetype=obj -o $@ diff --git a/samples/bpf/parse_ldabs.c b/samples/bpf/parse_ldabs.c new file mode 100644 index 0000000000000000000000000000000000000000..d17550198d0628e063e43a64253ec335a012c28f --- /dev/null +++ b/samples/bpf/parse_ldabs.c @@ -0,0 +1,41 @@ +/* Copyright (c) 2016 Facebook + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of version 2 of the GNU General Public + * License as published by the Free Software Foundation. + */ +#include +#include +#include +#include +#include +#include +#include "bpf_helpers.h" + +#define DEFAULT_PKTGEN_UDP_PORT 9 +#define IP_MF 0x2000 +#define IP_OFFSET 0x1FFF + +static inline int ip_is_fragment(struct __sk_buff *ctx, __u64 nhoff) +{ + return load_half(ctx, nhoff + offsetof(struct iphdr, frag_off)) + & (IP_MF | IP_OFFSET); +} + +SEC("ldabs") +int handle_ingress(struct __sk_buff *skb) +{ + __u64 troff = ETH_HLEN + sizeof(struct iphdr); + + if (load_half(skb, offsetof(struct ethhdr, h_proto)) != ETH_P_IP) + return 0; + if (load_byte(skb, ETH_HLEN + offsetof(struct iphdr, protocol)) != IPPROTO_UDP || + load_byte(skb, ETH_HLEN) != 0x45) + return 0; + if (ip_is_fragment(skb, ETH_HLEN)) + return 0; + if (load_half(skb, troff + offsetof(struct udphdr, dest)) == DEFAULT_PKTGEN_UDP_PORT) + return TC_ACT_SHOT; + return 0; +} +char _license[] SEC("license") = "GPL"; diff --git a/samples/bpf/parse_simple.c b/samples/bpf/parse_simple.c new file mode 100644 index 0000000000000000000000000000000000000000..cf2511c33905751bb6ed866bf6bba9b1fb8330f3 --- /dev/null +++ b/samples/bpf/parse_simple.c @@ -0,0 +1,48 @@ +/* Copyright (c) 2016 Facebook + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of version 2 of the GNU General Public + * License as published by the Free Software Foundation. + */ +#include +#include +#include +#include +#include +#include +#include +#include "bpf_helpers.h" + +#define DEFAULT_PKTGEN_UDP_PORT 9 + +/* copy of 'struct ethhdr' without __packed */ +struct eth_hdr { + unsigned char h_dest[ETH_ALEN]; + unsigned char h_source[ETH_ALEN]; + unsigned short h_proto; +}; + +SEC("simple") +int handle_ingress(struct __sk_buff *skb) +{ + void *data = (void *)(long)skb->data; + struct eth_hdr *eth = data; + struct iphdr *iph = data + sizeof(*eth); + struct udphdr *udp = data + sizeof(*eth) + sizeof(*iph); + void *data_end = (void *)(long)skb->data_end; + + /* single length check */ + if (data + sizeof(*eth) + sizeof(*iph) + sizeof(*udp) > data_end) + return 0; + + if (eth->h_proto != htons(ETH_P_IP)) + return 0; + if (iph->protocol != IPPROTO_UDP || iph->ihl != 5) + return 0; + if (ip_is_fragment(iph)) + return 0; + if (udp->dest == htons(DEFAULT_PKTGEN_UDP_PORT)) + return TC_ACT_SHOT; + return 0; +} +char _license[] SEC("license") = "GPL"; diff --git a/samples/bpf/parse_varlen.c b/samples/bpf/parse_varlen.c new file mode 100644 index 0000000000000000000000000000000000000000..edab34dce79b3794b010ca4138ef969d13c68535 --- /dev/null +++ b/samples/bpf/parse_varlen.c @@ -0,0 +1,153 @@ +/* Copyright (c) 2016 Facebook + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of version 2 of the GNU General Public + * License as published by the Free Software Foundation. + */ +#include +#include +#include +#include +#include +#include +#include +#include +#include "bpf_helpers.h" + +#define DEFAULT_PKTGEN_UDP_PORT 9 +#define DEBUG 0 + +static int tcp(void *data, uint64_t tp_off, void *data_end) +{ + struct tcphdr *tcp = data + tp_off; + + if (tcp + 1 > data_end) + return 0; + if (tcp->dest == htons(80) || tcp->source == htons(80)) + return TC_ACT_SHOT; + return 0; +} + +static int udp(void *data, uint64_t tp_off, void *data_end) +{ + struct udphdr *udp = data + tp_off; + + if (udp + 1 > data_end) + return 0; + if (udp->dest == htons(DEFAULT_PKTGEN_UDP_PORT) || + udp->source == htons(DEFAULT_PKTGEN_UDP_PORT)) { + if (DEBUG) { + char fmt[] = "udp port 9 indeed\n"; + + bpf_trace_printk(fmt, sizeof(fmt)); + } + return TC_ACT_SHOT; + } + return 0; +} + +static int parse_ipv4(void *data, uint64_t nh_off, void *data_end) +{ + struct iphdr *iph; + uint64_t ihl_len; + + iph = data + nh_off; + if (iph + 1 > data_end) + return 0; + + if (ip_is_fragment(iph)) + return 0; + ihl_len = iph->ihl * 4; + + if (iph->protocol == IPPROTO_IPIP) { + iph = data + nh_off + ihl_len; + if (iph + 1 > data_end) + return 0; + ihl_len += iph->ihl * 4; + } + + if (iph->protocol == IPPROTO_TCP) + return tcp(data, nh_off + ihl_len, data_end); + else if (iph->protocol == IPPROTO_UDP) + return udp(data, nh_off + ihl_len, data_end); + return 0; +} + +static int parse_ipv6(void *data, uint64_t nh_off, void *data_end) +{ + struct ipv6hdr *ip6h; + struct iphdr *iph; + uint64_t ihl_len = sizeof(struct ipv6hdr); + uint64_t nexthdr; + + ip6h = data + nh_off; + if (ip6h + 1 > data_end) + return 0; + + nexthdr = ip6h->nexthdr; + + if (nexthdr == IPPROTO_IPIP) { + iph = data + nh_off + ihl_len; + if (iph + 1 > data_end) + return 0; + ihl_len += iph->ihl * 4; + nexthdr = iph->protocol; + } else if (nexthdr == IPPROTO_IPV6) { + ip6h = data + nh_off + ihl_len; + if (ip6h + 1 > data_end) + return 0; + ihl_len += sizeof(struct ipv6hdr); + nexthdr = ip6h->nexthdr; + } + + if (nexthdr == IPPROTO_TCP) + return tcp(data, nh_off + ihl_len, data_end); + else if (nexthdr == IPPROTO_UDP) + return udp(data, nh_off + ihl_len, data_end); + return 0; +} + +struct vlan_hdr { + uint16_t h_vlan_TCI; + uint16_t h_vlan_encapsulated_proto; +}; + +SEC("varlen") +int handle_ingress(struct __sk_buff *skb) +{ + void *data = (void *)(long)skb->data; + struct ethhdr *eth = data; + void *data_end = (void *)(long)skb->data_end; + uint64_t h_proto, nh_off; + + nh_off = sizeof(*eth); + if (data + nh_off > data_end) + return 0; + + h_proto = eth->h_proto; + + if (h_proto == ETH_P_8021Q || h_proto == ETH_P_8021AD) { + struct vlan_hdr *vhdr; + + vhdr = data + nh_off; + nh_off += sizeof(struct vlan_hdr); + if (data + nh_off > data_end) + return 0; + h_proto = vhdr->h_vlan_encapsulated_proto; + } + if (h_proto == ETH_P_8021Q || h_proto == ETH_P_8021AD) { + struct vlan_hdr *vhdr; + + vhdr = data + nh_off; + nh_off += sizeof(struct vlan_hdr); + if (data + nh_off > data_end) + return 0; + h_proto = vhdr->h_vlan_encapsulated_proto; + } + if (h_proto == htons(ETH_P_IP)) + return parse_ipv4(data, nh_off, data_end); + else if (h_proto == htons(ETH_P_IPV6)) + return parse_ipv6(data, nh_off, data_end); + return 0; +} +char _license[] SEC("license") = "GPL"; diff --git a/samples/bpf/test_cls_bpf.sh b/samples/bpf/test_cls_bpf.sh new file mode 100755 index 0000000000000000000000000000000000000000..0365d5ee512cc78a881b23b4116d9416f718b0f6 --- /dev/null +++ b/samples/bpf/test_cls_bpf.sh @@ -0,0 +1,37 @@ +#!/bin/bash + +function pktgen { + ../pktgen/pktgen_bench_xmit_mode_netif_receive.sh -i $IFC -s 64 \ + -m 90:e2:ba:ff:ff:ff -d 192.168.0.1 -t 4 + local dropped=`tc -s qdisc show dev $IFC | tail -3 | awk '/drop/{print $7}'` + if [ "$dropped" == "0," ]; then + echo "FAIL" + else + echo "Successfully filtered " $dropped " packets" + fi +} + +function test { + echo -n "Loading bpf program '$2'... " + tc qdisc add dev $IFC clsact + tc filter add dev $IFC ingress bpf da obj $1 sec $2 + local status=$? + if [ $status -ne 0 ]; then + echo "FAIL" + else + echo "ok" + pktgen + fi + tc qdisc del dev $IFC clsact +} + +IFC=test_veth + +ip link add name $IFC type veth peer name pair_$IFC +ip link set $IFC up +ip link set pair_$IFC up + +test ./parse_simple.o simple +test ./parse_varlen.o varlen +test ./parse_ldabs.o ldabs +ip link del dev $IFC