diff options
| -rw-r--r-- | samples/bpf/Makefile | 4 | ||||
| -rw-r--r-- | samples/bpf/xdp_redirect_kern.c | 81 | ||||
| -rw-r--r-- | samples/bpf/xdp_redirect_user.c | 102 |
3 files changed, 187 insertions, 0 deletions
diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile index 87246be6feb8..97734ced947e 100644 --- a/samples/bpf/Makefile +++ b/samples/bpf/Makefile @@ -37,6 +37,7 @@ hostprogs-y += xdp_tx_iptunnel hostprogs-y += test_map_in_map hostprogs-y += per_socket_stats_example hostprogs-y += load_sock_ops +hostprogs-y += xdp_redirect # Libbpf dependencies LIBBPF := ../../tools/lib/bpf/bpf.o @@ -78,6 +79,7 @@ lwt_len_hist-objs := bpf_load.o $(LIBBPF) lwt_len_hist_user.o xdp_tx_iptunnel-objs := bpf_load.o $(LIBBPF) xdp_tx_iptunnel_user.o test_map_in_map-objs := bpf_load.o $(LIBBPF) test_map_in_map_user.o per_socket_stats_example-objs := $(LIBBPF) cookie_uid_helper_example.o +xdp_redirect-objs := bpf_load.o $(LIBBPF) xdp_redirect_user.o # Tell kbuild to always build the programs always := $(hostprogs-y) @@ -119,6 +121,7 @@ always += tcp_bufs_kern.o always += tcp_cong_kern.o always += tcp_iw_kern.o always += tcp_clamp_kern.o +always += xdp_redirect_kern.o HOSTCFLAGS += -I$(objtree)/usr/include HOSTCFLAGS += -I$(srctree)/tools/lib/ @@ -155,6 +158,7 @@ HOSTLOADLIBES_tc_l2_redirect += -l elf HOSTLOADLIBES_lwt_len_hist += -l elf HOSTLOADLIBES_xdp_tx_iptunnel += -lelf HOSTLOADLIBES_test_map_in_map += -lelf +HOSTLOADLIBES_xdp_redirect += -lelf # Allows pointing LLC/CLANG to a LLVM backend with bpf support, redefine on cmdline: # make samples/bpf/ LLC=~/git/llvm/build/bin/llc CLANG=~/git/llvm/build/bin/clang diff --git a/samples/bpf/xdp_redirect_kern.c b/samples/bpf/xdp_redirect_kern.c new file mode 100644 index 000000000000..a34ad457a684 --- /dev/null +++ b/samples/bpf/xdp_redirect_kern.c @@ -0,0 +1,81 @@ +/* Copyright (c) 2016 John Fastabend <john.r.fastabend@intel.com> + * + * 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. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + */ +#define KBUILD_MODNAME "foo" +#include <uapi/linux/bpf.h> +#include <linux/in.h> +#include <linux/if_ether.h> +#include <linux/if_packet.h> +#include <linux/if_vlan.h> +#include <linux/ip.h> +#include <linux/ipv6.h> +#include "bpf_helpers.h" + +struct bpf_map_def SEC("maps") tx_port = { + .type = BPF_MAP_TYPE_ARRAY, + .key_size = sizeof(int), + .value_size = sizeof(int), + .max_entries = 1, +}; + +struct bpf_map_def SEC("maps") rxcnt = { + .type = BPF_MAP_TYPE_PERCPU_ARRAY, + .key_size = sizeof(u32), + .value_size = sizeof(long), + .max_entries = 1, +}; + + +static void swap_src_dst_mac(void *data) +{ + unsigned short *p = data; + unsigned short dst[3]; + + dst[0] = p[0]; + dst[1] = p[1]; + dst[2] = p[2]; + p[0] = p[3]; + p[1] = p[4]; + p[2] = p[5]; + p[3] = dst[0]; + p[4] = dst[1]; + p[5] = dst[2]; +} + +SEC("xdp_redirect") +int xdp_redirect_prog(struct xdp_md *ctx) +{ + void *data_end = (void *)(long)ctx->data_end; + void *data = (void *)(long)ctx->data; + struct ethhdr *eth = data; + int rc = XDP_DROP; + int *ifindex, port = 0; + long *value; + u32 key = 0; + u64 nh_off; + + nh_off = sizeof(*eth); + if (data + nh_off > data_end) + return rc; + + ifindex = bpf_map_lookup_elem(&tx_port, &port); + if (!ifindex) + return rc; + + value = bpf_map_lookup_elem(&rxcnt, &key); + if (value) + *value += 1; + + swap_src_dst_mac(data); + return bpf_redirect(*ifindex, 0); +} + +char _license[] SEC("license") = "GPL"; diff --git a/samples/bpf/xdp_redirect_user.c b/samples/bpf/xdp_redirect_user.c new file mode 100644 index 000000000000..761a91d5d7b4 --- /dev/null +++ b/samples/bpf/xdp_redirect_user.c @@ -0,0 +1,102 @@ +/* Copyright (c) 2016 John Fastabend <john.r.fastabend@intel.com> + * + * 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. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + */ +#include <linux/bpf.h> +#include <assert.h> +#include <errno.h> +#include <signal.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> + +#include "bpf_load.h" +#include "bpf_util.h" +#include "libbpf.h" + +static int ifindex_in; +static int ifindex_out; + +static void int_exit(int sig) +{ + set_link_xdp_fd(ifindex_in, -1, 0); + exit(0); +} + +/* simple per-protocol drop counter + */ +static void poll_stats(int interval, int ifindex) +{ + unsigned int nr_cpus = bpf_num_possible_cpus(); + __u64 values[nr_cpus], prev[nr_cpus]; + + memset(prev, 0, sizeof(prev)); + + while (1) { + __u64 sum = 0; + __u32 key = 0; + int i; + + sleep(interval); + assert(bpf_map_lookup_elem(map_fd[1], &key, values) == 0); + for (i = 0; i < nr_cpus; i++) + sum += (values[i] - prev[i]); + if (sum) + printf("ifindex %i: %10llu pkt/s\n", + ifindex, sum / interval); + memcpy(prev, values, sizeof(values)); + } +} + +int main(int ac, char **argv) +{ + char filename[256]; + int ret, key = 0; + + snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]); + + if (ac != 3) { + printf("usage: %s IFINDEX_IN IFINDEX_OUT\n", argv[0]); + return 1; + } + + ifindex_in = strtoul(argv[1], NULL, 0); + ifindex_out = strtoul(argv[2], NULL, 0); + + if (load_bpf_file(filename)) { + printf("%s", bpf_log_buf); + return 1; + } + + if (!prog_fd[0]) { + printf("load_bpf_file: %s\n", strerror(errno)); + return 1; + } + + signal(SIGINT, int_exit); + + if (set_link_xdp_fd(ifindex_in, prog_fd[0], 0) < 0) { + printf("link set xdp fd failed\n"); + return 1; + } + + /* bpf redirect port */ + ret = bpf_map_update_elem(map_fd[0], &key, &ifindex_out, 0); + if (ret) { + perror("bpf_update_elem"); + goto out; + } + + poll_stats(2, ifindex_out); + +out: + return 0; +} |