Commit bbe65865 authored by Kumar Kartikeya Dwivedi's avatar Kumar Kartikeya Dwivedi Committed by Alexei Starovoitov
Browse files

samples: bpf: Convert xdp_redirect_map to XDP samples helper 



Use the libbpf skeleton facility and other utilities provided by XDP
samples helper.

Since get_mac_addr is already provided by XDP samples helper, we drop
it. Also convert to XDP samples helper similar to prior samples to
minimize duplication of code.

Signed-off-by: default avatarKumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210821002010.845777-21-memxor@gmail.com
parent 54af769d

samples/bpf/Makefile

+3 −2
Original line number Diff line number Diff line
@@ -39,7 +39,6 @@ tprogs-y += lwt_len_hist 
tprogs-y += xdp_tx_iptunnel

tprogs-y += test_map_in_map

tprogs-y += per_socket_stats_example

tprogs-y += xdp_redirect_map

tprogs-y += xdp_redirect_map_multi

tprogs-y += xdp_rxq_info

tprogs-y += syscall_tp
@@ -55,6 +54,7 @@ tprogs-y += ibumad 
tprogs-y += hbm



tprogs-y += xdp_redirect_cpu

tprogs-y += xdp_redirect_map

tprogs-y += xdp_redirect

tprogs-y += xdp_monitor
@@ -100,7 +100,6 @@ lwt_len_hist-objs := lwt_len_hist_user.o 
xdp_tx_iptunnel-objs := xdp_tx_iptunnel_user.o

test_map_in_map-objs := test_map_in_map_user.o

per_socket_stats_example-objs := cookie_uid_helper_example.o

xdp_redirect_map-objs := xdp_redirect_map_user.o

xdp_redirect_map_multi-objs := xdp_redirect_map_multi_user.o

xdp_rxq_info-objs := xdp_rxq_info_user.o

syscall_tp-objs := syscall_tp_user.o
@@ -116,6 +115,7 @@ ibumad-objs := ibumad_user.o 
hbm-objs := hbm.o $(CGROUP_HELPERS)



xdp_redirect_cpu-objs := xdp_redirect_cpu_user.o $(XDP_SAMPLE)

xdp_redirect_map-objs := xdp_redirect_map_user.o $(XDP_SAMPLE)

xdp_redirect-objs := xdp_redirect_user.o $(XDP_SAMPLE)

xdp_monitor-objs := xdp_monitor_user.o $(XDP_SAMPLE)
@@ -311,6 +311,7 @@ $(BPF_SAMPLES_PATH)/*.c: verify_target_bpf $(LIBBPF) 
$(src)/*.c: verify_target_bpf $(LIBBPF)



$(obj)/xdp_redirect_cpu_user.o: $(obj)/xdp_redirect_cpu.skel.h

$(obj)/xdp_redirect_map_user.o: $(obj)/xdp_redirect_map.skel.h

$(obj)/xdp_redirect_user.o: $(obj)/xdp_redirect.skel.h

$(obj)/xdp_monitor_user.o: $(obj)/xdp_monitor.skel.h

samples/bpf/xdp_redirect_map_user.c

+158 −227
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0-only

/* Copyright (c) 2017 Covalent IO, Inc. http://covalent.io

 */

static const char *__doc__ =

"XDP redirect tool, using BPF_MAP_TYPE_DEVMAP\n"

"Usage: xdp_redirect_map <IFINDEX|IFNAME>_IN <IFINDEX|IFNAME>_OUT\n";



#include <linux/bpf.h>

#include <linux/if_link.h>

#include <assert.h>
@@ -13,165 +17,83 @@ 
#include <net/if.h>

#include <unistd.h>

#include <libgen.h>

#include <sys/resource.h>

#include <sys/ioctl.h>

#include <sys/types.h>

#include <sys/socket.h>

#include <netinet/in.h>



#include "bpf_util.h"

#include <getopt.h>

#include <bpf/bpf.h>

#include <bpf/libbpf.h>



static int ifindex_in;

static int ifindex_out;

static bool ifindex_out_xdp_dummy_attached = true;

static bool xdp_devmap_attached;

static __u32 prog_id;

static __u32 dummy_prog_id;



static __u32 xdp_flags = XDP_FLAGS_UPDATE_IF_NOEXIST;

static int rxcnt_map_fd;



static void int_exit(int sig)

{

	__u32 curr_prog_id = 0;



	if (bpf_get_link_xdp_id(ifindex_in, &curr_prog_id, xdp_flags)) {

		printf("bpf_get_link_xdp_id failed\n");

		exit(1);

	}

	if (prog_id == curr_prog_id)

		bpf_set_link_xdp_fd(ifindex_in, -1, xdp_flags);

	else if (!curr_prog_id)

		printf("couldn't find a prog id on iface IN\n");

	else

		printf("program on iface IN changed, not removing\n");



	if (ifindex_out_xdp_dummy_attached) {

		curr_prog_id = 0;

		if (bpf_get_link_xdp_id(ifindex_out, &curr_prog_id,

					xdp_flags)) {

			printf("bpf_get_link_xdp_id failed\n");

			exit(1);

		}

		if (dummy_prog_id == curr_prog_id)

			bpf_set_link_xdp_fd(ifindex_out, -1, xdp_flags);

		else if (!curr_prog_id)

			printf("couldn't find a prog id on iface OUT\n");

		else

			printf("program on iface OUT changed, not removing\n");

	}

	exit(0);

}



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(rxcnt_map_fd, &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));

	}

}



static int get_mac_addr(unsigned int ifindex_out, void *mac_addr)

{

	char ifname[IF_NAMESIZE];

	struct ifreq ifr;

	int fd, ret = -1;



	fd = socket(AF_INET, SOCK_DGRAM, 0);

	if (fd < 0)

		return ret;



	if (!if_indextoname(ifindex_out, ifname))

		goto err_out;



	strcpy(ifr.ifr_name, ifname);



	if (ioctl(fd, SIOCGIFHWADDR, &ifr) != 0)

		goto err_out;



	memcpy(mac_addr, ifr.ifr_hwaddr.sa_data, 6 * sizeof(char));

	ret = 0;



err_out:

	close(fd);

	return ret;

}



static void usage(const char *prog)

{

	fprintf(stderr,

		"usage: %s [OPTS] <IFNAME|IFINDEX>_IN <IFNAME|IFINDEX>_OUT\n\n"

		"OPTS:\n"

		"    -S    use skb-mode\n"

		"    -N    enforce native mode\n"

		"    -F    force loading prog\n"

		"    -X    load xdp program on egress\n",

		prog);

}

#include "bpf_util.h"

#include "xdp_sample_user.h"

#include "xdp_redirect_map.skel.h"



static int mask = SAMPLE_RX_CNT | SAMPLE_REDIRECT_ERR_MAP_CNT |

		  SAMPLE_EXCEPTION_CNT | SAMPLE_DEVMAP_XMIT_CNT_MULTI;



DEFINE_SAMPLE_INIT(xdp_redirect_map);



static const struct option long_options[] = {

	{ "help", no_argument, NULL, 'h' },

	{ "skb-mode", no_argument, NULL, 'S' },

	{ "force", no_argument, NULL, 'F' },

	{ "load-egress", no_argument, NULL, 'X' },

	{ "stats", no_argument, NULL, 's' },

	{ "interval", required_argument, NULL, 'i' },

	{ "verbose", no_argument, NULL, 'v' },

	{}

};



int main(int argc, char **argv)

{

	struct bpf_prog_load_attr prog_load_attr = {

		.prog_type	= BPF_PROG_TYPE_UNSPEC,

	};

	struct bpf_program *prog, *dummy_prog, *devmap_prog;

	int prog_fd, dummy_prog_fd, devmap_prog_fd = 0;

	int tx_port_map_fd, tx_mac_map_fd;

	struct bpf_devmap_val devmap_val;

	struct bpf_prog_info info = {};

	__u32 info_len = sizeof(info);

	const char *optstr = "FSNX";

	struct bpf_object *obj;

	int ret, opt, key = 0;

	char filename[256];



	while ((opt = getopt(argc, argv, optstr)) != -1) {

	struct bpf_devmap_val devmap_val = {};

	bool xdp_devmap_attached = false;

	struct xdp_redirect_map *skel;

	char str[2 * IF_NAMESIZE + 1];

	char ifname_out[IF_NAMESIZE];

	struct bpf_map *tx_port_map;

	char ifname_in[IF_NAMESIZE];

	int ifindex_in, ifindex_out;

	unsigned long interval = 2;

	int ret = EXIT_FAIL_OPTION;

	struct bpf_program *prog;

	bool generic = false;

	bool force = false;

	bool tried = false;

	bool error = true;

	int opt, key = 0;



	while ((opt = getopt_long(argc, argv, "hSFXi:vs",

				  long_options, NULL)) != -1) {

		switch (opt) {

		case 'S':

			xdp_flags |= XDP_FLAGS_SKB_MODE;

			break;

		case 'N':

			/* default, set below */

			generic = true;

			/* devmap_xmit tracepoint not available */

			mask &= ~(SAMPLE_DEVMAP_XMIT_CNT |

				  SAMPLE_DEVMAP_XMIT_CNT_MULTI);

			break;

		case 'F':

			xdp_flags &= ~XDP_FLAGS_UPDATE_IF_NOEXIST;

			force = true;

			break;

		case 'X':

			xdp_devmap_attached = true;

			break;

		case 'i':

			interval = strtoul(optarg, NULL, 0);

			break;

		case 'v':

			sample_switch_mode();

			break;

		case 's':

			mask |= SAMPLE_REDIRECT_MAP_CNT;

			break;

		case 'h':

			error = false;

		default:

			usage(basename(argv[0]));

			return 1;

		}

			sample_usage(argv, long_options, __doc__, mask, error);

			return ret;

		}



	if (!(xdp_flags & XDP_FLAGS_SKB_MODE)) {

		xdp_flags |= XDP_FLAGS_DRV_MODE;

	} else if (xdp_devmap_attached) {

		printf("Load xdp program on egress with SKB mode not supported yet\n");

		return 1;

	}



	if (optind == argc) {

		printf("usage: %s <IFNAME|IFINDEX>_IN <IFNAME|IFINDEX>_OUT\n", argv[0]);

		return 1;

	if (argc <= optind + 1) {

		sample_usage(argv, long_options, __doc__, mask, true);

		goto end;

	}



	ifindex_in = if_nametoindex(argv[optind]);
@@ -182,107 +104,116 @@ int main(int argc, char **argv) 
	if (!ifindex_out)

		ifindex_out = strtoul(argv[optind + 1], NULL, 0);



	printf("input: %d output: %d\n", ifindex_in, ifindex_out);



	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);

	prog_load_attr.file = filename;



	if (bpf_prog_load_xattr(&prog_load_attr, &obj, &prog_fd))

		return 1;



	if (xdp_flags & XDP_FLAGS_SKB_MODE) {

		prog = bpf_object__find_program_by_name(obj, "xdp_redirect_map_general");

		tx_port_map_fd = bpf_object__find_map_fd_by_name(obj, "tx_port_general");

	} else {

		prog = bpf_object__find_program_by_name(obj, "xdp_redirect_map_native");

		tx_port_map_fd = bpf_object__find_map_fd_by_name(obj, "tx_port_native");

	}

	dummy_prog = bpf_object__find_program_by_name(obj, "xdp_redirect_dummy_prog");

	if (!prog || dummy_prog < 0 || tx_port_map_fd < 0) {

		printf("finding prog/dummy_prog/tx_port_map in obj file failed\n");

		goto out;

	}

	prog_fd = bpf_program__fd(prog);

	dummy_prog_fd = bpf_program__fd(dummy_prog);

	if (prog_fd < 0 || dummy_prog_fd < 0 || tx_port_map_fd < 0) {

		printf("bpf_prog_load_xattr: %s\n", strerror(errno));

		return 1;

	}



	tx_mac_map_fd = bpf_object__find_map_fd_by_name(obj, "tx_mac");

	rxcnt_map_fd = bpf_object__find_map_fd_by_name(obj, "rxcnt");

	if (tx_mac_map_fd < 0 || rxcnt_map_fd < 0) {

		printf("bpf_object__find_map_fd_by_name failed\n");

		return 1;

	if (!ifindex_in || !ifindex_out) {

		fprintf(stderr, "Bad interface index or name\n");

		sample_usage(argv, long_options, __doc__, mask, true);

		goto end;

	}



	if (bpf_set_link_xdp_fd(ifindex_in, prog_fd, xdp_flags) < 0) {

		printf("ERROR: link set xdp fd failed on %d\n", ifindex_in);

		return 1;

	skel = xdp_redirect_map__open();

	if (!skel) {

		fprintf(stderr, "Failed to xdp_redirect_map__open: %s\n",

			strerror(errno));

		ret = EXIT_FAIL_BPF;

		goto end;

	}



	ret = bpf_obj_get_info_by_fd(prog_fd, &info, &info_len);

	if (ret) {

		printf("can't get prog info - %s\n", strerror(errno));

		return ret;

	ret = sample_init_pre_load(skel);

	if (ret < 0) {

		fprintf(stderr, "Failed to sample_init_pre_load: %s\n", strerror(-ret));

		ret = EXIT_FAIL_BPF;

		goto end_destroy;

	}

	prog_id = info.id;



	/* Loading dummy XDP prog on out-device */

	if (bpf_set_link_xdp_fd(ifindex_out, dummy_prog_fd,

			    (xdp_flags | XDP_FLAGS_UPDATE_IF_NOEXIST)) < 0) {

		printf("WARN: link set xdp fd failed on %d\n", ifindex_out);

		ifindex_out_xdp_dummy_attached = false;

	/* Load 2nd xdp prog on egress. */

	if (xdp_devmap_attached) {

		ret = get_mac_addr(ifindex_out, skel->rodata->tx_mac_addr);

		if (ret < 0) {

			fprintf(stderr, "Failed to get interface %d mac address: %s\n",

				ifindex_out, strerror(-ret));

			ret = EXIT_FAIL;

			goto end_destroy;

		}



	memset(&info, 0, sizeof(info));

	ret = bpf_obj_get_info_by_fd(dummy_prog_fd, &info, &info_len);

	if (ret) {

		printf("can't get prog info - %s\n", strerror(errno));

		return ret;

	}

	dummy_prog_id = info.id;



	/* Load 2nd xdp prog on egress. */

	if (xdp_devmap_attached) {

		unsigned char mac_addr[6];

	skel->rodata->from_match[0] = ifindex_in;

	skel->rodata->to_match[0] = ifindex_out;



		devmap_prog = bpf_object__find_program_by_name(obj, "xdp_redirect_map_egress");

		if (!devmap_prog) {

			printf("finding devmap_prog in obj file failed\n");

			goto out;

		}

		devmap_prog_fd = bpf_program__fd(devmap_prog);

		if (devmap_prog_fd < 0) {

			printf("finding devmap_prog fd failed\n");

			goto out;

	ret = xdp_redirect_map__load(skel);

	if (ret < 0) {

		fprintf(stderr, "Failed to xdp_redirect_map__load: %s\n",

			strerror(errno));

		ret = EXIT_FAIL_BPF;

		goto end_destroy;

	}



		if (get_mac_addr(ifindex_out, mac_addr) < 0) {

			printf("get interface %d mac failed\n", ifindex_out);

			goto out;

	ret = sample_init(skel, mask);

	if (ret < 0) {

		fprintf(stderr, "Failed to initialize sample: %s\n", strerror(-ret));

		ret = EXIT_FAIL;

		goto end_destroy;

	}



		ret = bpf_map_update_elem(tx_mac_map_fd, &key, mac_addr, 0);

		if (ret) {

			perror("bpf_update_elem tx_mac_map_fd");

			goto out;

	prog = skel->progs.xdp_redirect_map_native;

	tx_port_map = skel->maps.tx_port_native;

restart:

	if (sample_install_xdp(prog, ifindex_in, generic, force) < 0) {

		/* First try with struct bpf_devmap_val as value for generic

		 * mode, then fallback to sizeof(int) for older kernels.

		 */

		fprintf(stderr,

			"Trying fallback to sizeof(int) as value_size for devmap in generic mode\n");

		if (generic && !tried) {

			prog = skel->progs.xdp_redirect_map_general;

			tx_port_map = skel->maps.tx_port_general;

			tried = true;

			goto restart;

		}

		ret = EXIT_FAIL_XDP;

		goto end_destroy;

	}



	signal(SIGINT, int_exit);

	signal(SIGTERM, int_exit);

	/* Loading dummy XDP prog on out-device */

	sample_install_xdp(skel->progs.xdp_redirect_dummy_prog, ifindex_out, generic, force);



	devmap_val.ifindex = ifindex_out;

	devmap_val.bpf_prog.fd = devmap_prog_fd;

	ret = bpf_map_update_elem(tx_port_map_fd, &key, &devmap_val, 0);

	if (ret) {

		perror("bpf_update_elem");

		goto out;

	}



	poll_stats(2, ifindex_out);



out:

	return 0;

	if (xdp_devmap_attached)

		devmap_val.bpf_prog.fd = bpf_program__fd(skel->progs.xdp_redirect_map_egress);

	ret = bpf_map_update_elem(bpf_map__fd(tx_port_map), &key, &devmap_val, 0);

	if (ret < 0) {

		fprintf(stderr, "Failed to update devmap value: %s\n",

			strerror(errno));

		ret = EXIT_FAIL_BPF;

		goto end_destroy;

	}



	ret = EXIT_FAIL;

	if (!if_indextoname(ifindex_in, ifname_in)) {

		fprintf(stderr, "Failed to if_indextoname for %d: %s\n", ifindex_in,

			strerror(errno));

		goto end_destroy;

	}



	if (!if_indextoname(ifindex_out, ifname_out)) {

		fprintf(stderr, "Failed to if_indextoname for %d: %s\n", ifindex_out,

			strerror(errno));

		goto end_destroy;

	}



	safe_strncpy(str, get_driver_name(ifindex_in), sizeof(str));

	printf("Redirecting from %s (ifindex %d; driver %s) to %s (ifindex %d; driver %s)\n",

	       ifname_in, ifindex_in, str, ifname_out, ifindex_out, get_driver_name(ifindex_out));

	snprintf(str, sizeof(str), "%s->%s", ifname_in, ifname_out);



	ret = sample_run(interval, NULL, NULL);

	if (ret < 0) {

		fprintf(stderr, "Failed during sample run: %s\n", strerror(-ret));

		ret = EXIT_FAIL;

		goto end_destroy;

	}

	ret = EXIT_OK;

end_destroy:

	xdp_redirect_map__destroy(skel);

end:

	sample_exit(ret);

}