diff options
Diffstat (limited to 'samples')
| -rw-r--r-- | samples/bpf/Makefile | 3 | ||||
| -rw-r--r-- | samples/bpf/bpf_helpers.h | 2 | ||||
| -rw-r--r-- | samples/bpf/test_cgrp2_array_pin.c | 109 | ||||
| -rwxr-xr-x | samples/bpf/test_cgrp2_tc.sh | 184 | ||||
| -rw-r--r-- | samples/bpf/test_cgrp2_tc_kern.c | 69 |
5 files changed, 367 insertions, 0 deletions
diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile index 0bf2478..a98b780 100644 --- a/samples/bpf/Makefile +++ b/samples/bpf/Makefile @@ -20,6 +20,7 @@ hostprogs-y += offwaketime hostprogs-y += spintest hostprogs-y += map_perf_test hostprogs-y += test_overhead +hostprogs-y += test_cgrp2_array_pin test_verifier-objs := test_verifier.o libbpf.o test_maps-objs := test_maps.o libbpf.o @@ -40,6 +41,7 @@ offwaketime-objs := bpf_load.o libbpf.o offwaketime_user.o spintest-objs := bpf_load.o libbpf.o spintest_user.o map_perf_test-objs := bpf_load.o libbpf.o map_perf_test_user.o test_overhead-objs := bpf_load.o libbpf.o test_overhead_user.o +test_cgrp2_array_pin-objs := libbpf.o test_cgrp2_array_pin.o # Tell kbuild to always build the programs always := $(hostprogs-y) @@ -61,6 +63,7 @@ always += map_perf_test_kern.o always += test_overhead_tp_kern.o always += test_overhead_kprobe_kern.o always += parse_varlen.o parse_simple.o parse_ldabs.o +always += test_cgrp2_tc_kern.o HOSTCFLAGS += -I$(objtree)/usr/include diff --git a/samples/bpf/bpf_helpers.h b/samples/bpf/bpf_helpers.h index 7904a2a..84e3fd9 100644 --- a/samples/bpf/bpf_helpers.h +++ b/samples/bpf/bpf_helpers.h @@ -70,6 +70,8 @@ static int (*bpf_l3_csum_replace)(void *ctx, int off, int from, int to, int flag (void *) BPF_FUNC_l3_csum_replace; static int (*bpf_l4_csum_replace)(void *ctx, int off, int from, int to, int flags) = (void *) BPF_FUNC_l4_csum_replace; +static int (*bpf_skb_in_cgroup)(void *ctx, void *map, int index) = + (void *) BPF_FUNC_skb_in_cgroup; #if defined(__x86_64__) diff --git a/samples/bpf/test_cgrp2_array_pin.c b/samples/bpf/test_cgrp2_array_pin.c new file mode 100644 index 0000000..70e86f7 --- /dev/null +++ b/samples/bpf/test_cgrp2_array_pin.c @@ -0,0 +1,109 @@ +/* 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 <linux/unistd.h> +#include <linux/bpf.h> + +#include <stdio.h> +#include <stdint.h> +#include <unistd.h> +#include <string.h> +#include <errno.h> +#include <fcntl.h> + +#include "libbpf.h" + +static void usage(void) +{ + printf("Usage: test_cgrp2_array_pin [...]\n"); + printf(" -F <file> File to pin an BPF cgroup array\n"); + printf(" -U <file> Update an already pinned BPF cgroup array\n"); + printf(" -v <value> Full path of the cgroup2\n"); + printf(" -h Display this help\n"); +} + +int main(int argc, char **argv) +{ + const char *pinned_file = NULL, *cg2 = NULL; + int create_array = 1; + int array_key = 0; + int array_fd = -1; + int cg2_fd = -1; + int ret = -1; + int opt; + + while ((opt = getopt(argc, argv, "F:U:v:")) != -1) { + switch (opt) { + /* General args */ + case 'F': + pinned_file = optarg; + break; + case 'U': + pinned_file = optarg; + create_array = 0; + break; + case 'v': + cg2 = optarg; + break; + default: + usage(); + goto out; + } + } + + if (!cg2 || !pinned_file) { + usage(); + goto out; + } + + cg2_fd = open(cg2, O_RDONLY); + if (cg2_fd < 0) { + fprintf(stderr, "open(%s,...): %s(%d)\n", + cg2, strerror(errno), errno); + goto out; + } + + if (create_array) { + array_fd = bpf_create_map(BPF_MAP_TYPE_CGROUP_ARRAY, + sizeof(uint32_t), sizeof(uint32_t), + 1, 0); + if (array_fd < 0) { + fprintf(stderr, + "bpf_create_map(BPF_MAP_TYPE_CGROUP_ARRAY,...): %s(%d)\n", + strerror(errno), errno); + goto out; + } + } else { + array_fd = bpf_obj_get(pinned_file); + if (array_fd < 0) { + fprintf(stderr, "bpf_obj_get(%s): %s(%d)\n", + pinned_file, strerror(errno), errno); + goto out; + } + } + + ret = bpf_update_elem(array_fd, &array_key, &cg2_fd, 0); + if (ret) { + perror("bpf_update_elem"); + goto out; + } + + if (create_array) { + ret = bpf_obj_pin(array_fd, pinned_file); + if (ret) { + fprintf(stderr, "bpf_obj_pin(..., %s): %s(%d)\n", + pinned_file, strerror(errno), errno); + goto out; + } + } + +out: + if (array_fd != -1) + close(array_fd); + if (cg2_fd != -1) + close(cg2_fd); + return ret; +} diff --git a/samples/bpf/test_cgrp2_tc.sh b/samples/bpf/test_cgrp2_tc.sh new file mode 100755 index 0000000..0b119ee --- /dev/null +++ b/samples/bpf/test_cgrp2_tc.sh @@ -0,0 +1,184 @@ +#!/bin/bash + +MY_DIR=$(dirname $0) +# Details on the bpf prog +BPF_CGRP2_ARRAY_NAME='test_cgrp2_array_pin' +BPF_PROG="$MY_DIR/test_cgrp2_tc_kern.o" +BPF_SECTION='filter' + +[ -z "$TC" ] && TC='tc' +[ -z "$IP" ] && IP='ip' + +# Names of the veth interface, net namespace...etc. +HOST_IFC='ve' +NS_IFC='vens' +NS='ns' + +find_mnt() { + cat /proc/mounts | \ + awk '{ if ($3 == "'$1'" && mnt == "") { mnt = $2 }} END { print mnt }' +} + +# Init cgroup2 vars +init_cgrp2_vars() { + CGRP2_ROOT=$(find_mnt cgroup2) + if [ -z "$CGRP2_ROOT" ] + then + CGRP2_ROOT='/mnt/cgroup2' + MOUNT_CGRP2="yes" + fi + CGRP2_TC="$CGRP2_ROOT/tc" + CGRP2_TC_LEAF="$CGRP2_TC/leaf" +} + +# Init bpf fs vars +init_bpf_fs_vars() { + local bpf_fs_root=$(find_mnt bpf) + [ -n "$bpf_fs_root" ] || return -1 + BPF_FS_TC_SHARE="$bpf_fs_root/tc/globals" +} + +setup_cgrp2() { + case $1 in + start) + if [ "$MOUNT_CGRP2" == 'yes' ] + then + [ -d $CGRP2_ROOT ] || mkdir -p $CGRP2_ROOT + mount -t cgroup2 none $CGRP2_ROOT || return $? + fi + mkdir -p $CGRP2_TC_LEAF + ;; + *) + rmdir $CGRP2_TC_LEAF && rmdir $CGRP2_TC + [ "$MOUNT_CGRP2" == 'yes' ] && umount $CGRP2_ROOT + ;; + esac +} + +setup_bpf_cgrp2_array() { + local bpf_cgrp2_array="$BPF_FS_TC_SHARE/$BPF_CGRP2_ARRAY_NAME" + case $1 in + start) + $MY_DIR/test_cgrp2_array_pin -U $bpf_cgrp2_array -v $CGRP2_TC + ;; + *) + [ -d "$BPF_FS_TC_SHARE" ] && rm -f $bpf_cgrp2_array + ;; + esac +} + +setup_net() { + case $1 in + start) + $IP link add $HOST_IFC type veth peer name $NS_IFC || return $? + $IP link set dev $HOST_IFC up || return $? + sysctl -q net.ipv6.conf.$HOST_IFC.accept_dad=0 + + $IP netns add ns || return $? + $IP link set dev $NS_IFC netns ns || return $? + $IP -n $NS link set dev $NS_IFC up || return $? + $IP netns exec $NS sysctl -q net.ipv6.conf.$NS_IFC.accept_dad=0 + $TC qdisc add dev $HOST_IFC clsact || return $? + $TC filter add dev $HOST_IFC egress bpf da obj $BPF_PROG sec $BPF_SECTION || return $? + ;; + *) + $IP netns del $NS + $IP link del $HOST_IFC + ;; + esac +} + +run_in_cgrp() { + # Fork another bash and move it under the specified cgroup. + # It makes the cgroup cleanup easier at the end of the test. + cmd='echo $$ > ' + cmd="$cmd $1/cgroup.procs; exec $2" + bash -c "$cmd" +} + +do_test() { + run_in_cgrp $CGRP2_TC_LEAF "ping -6 -c3 ff02::1%$HOST_IFC >& /dev/null" + local dropped=$($TC -s qdisc show dev $HOST_IFC | tail -3 | \ + awk '/drop/{print substr($7, 0, index($7, ",")-1)}') + if [[ $dropped -eq 0 ]] + then + echo "FAIL" + return 1 + else + echo "Successfully filtered $dropped packets" + return 0 + fi +} + +do_exit() { + if [ "$DEBUG" == "yes" ] && [ "$MODE" != 'cleanuponly' ] + then + echo "------ DEBUG ------" + echo "mount: "; mount | egrep '(cgroup2|bpf)'; echo + echo "$CGRP2_TC_LEAF: "; ls -l $CGRP2_TC_LEAF; echo + if [ -d "$BPF_FS_TC_SHARE" ] + then + echo "$BPF_FS_TC_SHARE: "; ls -l $BPF_FS_TC_SHARE; echo + fi + echo "Host net:" + $IP netns + $IP link show dev $HOST_IFC + $IP -6 a show dev $HOST_IFC + $TC -s qdisc show dev $HOST_IFC + echo + echo "$NS net:" + $IP -n $NS link show dev $NS_IFC + $IP -n $NS -6 link show dev $NS_IFC + echo "------ DEBUG ------" + echo + fi + + if [ "$MODE" != 'nocleanup' ] + then + setup_net stop + setup_bpf_cgrp2_array stop + setup_cgrp2 stop + fi +} + +init_cgrp2_vars +init_bpf_fs_vars + +while [[ $# -ge 1 ]] +do + a="$1" + case $a in + debug) + DEBUG='yes' + shift 1 + ;; + cleanup-only) + MODE='cleanuponly' + shift 1 + ;; + no-cleanup) + MODE='nocleanup' + shift 1 + ;; + *) + echo "test_cgrp2_tc [debug] [cleanup-only | no-cleanup]" + echo " debug: Print cgrp and network setup details at the end of the test" + echo " cleanup-only: Try to cleanup things from last test. No test will be run" + echo " no-cleanup: Run the test but don't do cleanup at the end" + echo "[Note: If no arg is given, it will run the test and do cleanup at the end]" + echo + exit -1 + ;; + esac +done + +trap do_exit 0 + +[ "$MODE" == 'cleanuponly' ] && exit + +setup_cgrp2 start || exit $? +setup_net start || exit $? +init_bpf_fs_vars || exit $? +setup_bpf_cgrp2_array start || exit $? +do_test +echo diff --git a/samples/bpf/test_cgrp2_tc_kern.c b/samples/bpf/test_cgrp2_tc_kern.c new file mode 100644 index 0000000..2732c37 --- /dev/null +++ b/samples/bpf/test_cgrp2_tc_kern.c @@ -0,0 +1,69 @@ +/* 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 <uapi/linux/if_ether.h> +#include <uapi/linux/in6.h> +#include <uapi/linux/ipv6.h> +#include <uapi/linux/pkt_cls.h> +#include <uapi/linux/bpf.h> +#include "bpf_helpers.h" + +/* 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; +}; + +#define PIN_GLOBAL_NS 2 +struct bpf_elf_map { + __u32 type; + __u32 size_key; + __u32 size_value; + __u32 max_elem; + __u32 flags; + __u32 id; + __u32 pinning; +}; + +struct bpf_elf_map SEC("maps") test_cgrp2_array_pin = { + .type = BPF_MAP_TYPE_CGROUP_ARRAY, + .size_key = sizeof(uint32_t), + .size_value = sizeof(uint32_t), + .pinning = PIN_GLOBAL_NS, + .max_elem = 1, +}; + +SEC("filter") +int handle_egress(struct __sk_buff *skb) +{ + void *data = (void *)(long)skb->data; + struct eth_hdr *eth = data; + struct ipv6hdr *ip6h = data + sizeof(*eth); + void *data_end = (void *)(long)skb->data_end; + char dont_care_msg[] = "dont care %04x %d\n"; + char pass_msg[] = "pass\n"; + char reject_msg[] = "reject\n"; + + /* single length check */ + if (data + sizeof(*eth) + sizeof(*ip6h) > data_end) + return TC_ACT_OK; + + if (eth->h_proto != htons(ETH_P_IPV6) || + ip6h->nexthdr != IPPROTO_ICMPV6) { + bpf_trace_printk(dont_care_msg, sizeof(dont_care_msg), + eth->h_proto, ip6h->nexthdr); + return TC_ACT_OK; + } else if (bpf_skb_in_cgroup(skb, &test_cgrp2_array_pin, 0) != 1) { + bpf_trace_printk(pass_msg, sizeof(pass_msg)); + return TC_ACT_OK; + } else { + bpf_trace_printk(reject_msg, sizeof(reject_msg)); + return TC_ACT_SHOT; + } +} + +char _license[] SEC("license") = "GPL"; |
