samples/bpf/xdp_tx_iptunnel_user.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0-only
 /* Copyright (c) 2016 Facebook
  */
 #include <linux/bpf.h>
 #include <linux/if_link.h>
 #include <assert.h>
 #include <errno.h>
 #include <signal.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <net/if.h>
 #include <sys/resource.h>
 #include <arpa/inet.h>
 #include <netinet/ether.h>
 #include <unistd.h>
 #include <time.h>
 #include <bpf/libbpf.h>
 #include <bpf/bpf.h>
 #include "bpf_util.h"
 #include "xdp_tx_iptunnel_common.h"

 #define STATS_INTERVAL_S 2U

 static int ifindex = -1;
 static __u32 xdp_flags = XDP_FLAGS_UPDATE_IF_NOEXIST;
 static int rxcnt_map_fd;
 static __u32 prog_id;

 static void int_exit(int sig)
 {
 	__u32 curr_prog_id = 0;

 	if (ifindex > -1) {
 		if (bpf_get_link_xdp_id(ifindex, &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, -1, xdp_flags);
 		else if (!curr_prog_id)
 			printf("couldn't find a prog id on a given iface\n");
 		else
 			printf("program on interface changed, not removing\n");
 	}
 	exit(0);
 }

 /* simple per-protocol drop counter
  */
 static void poll_stats(unsigned int kill_after_s)
 {
 	const unsigned int nr_protos = 256;
 	unsigned int nr_cpus = bpf_num_possible_cpus();
 	time_t started_at = time(NULL);
 	__u64 values[nr_cpus], prev[nr_protos][nr_cpus];
 	__u32 proto;
 	int i;

 	memset(prev, 0, sizeof(prev));

 	while (!kill_after_s || time(NULL) - started_at <= kill_after_s) {
 		sleep(STATS_INTERVAL_S);

 		for (proto = 0; proto < nr_protos; proto++) {
 			__u64 sum = 0;

 			assert(bpf_map_lookup_elem(rxcnt_map_fd, &proto,
 						   values) == 0);
 			for (i = 0; i < nr_cpus; i++)
 				sum += (values[i] - prev[proto][i]);

 			if (sum)
 				printf("proto %u: sum:%10llu pkts, rate:%10llu pkts/s\n",
 				       proto, sum, sum / STATS_INTERVAL_S);
 			memcpy(prev[proto], values, sizeof(values));
 		}
 	}
 }

 static void usage(const char *cmd)
 {
 	printf("Start a XDP prog which encapsulates incoming packets\n"
 	       "in an IPv4/v6 header and XDP_TX it out.  The dst <VIP:PORT>\n"
 	       "is used to select packets to encapsulate\n\n");
 	printf("Usage: %s [...]\n", cmd);
 	printf("    -i <ifname|ifindex> Interface\n");
 	printf("    -a <vip-service-address> IPv4 or IPv6\n");
 	printf("    -p <vip-service-port> A port range (e.g. 433-444) is also allowed\n");
 	printf("    -s <source-ip> Used in the IPTunnel header\n");
 	printf("    -d <dest-ip> Used in the IPTunnel header\n");
 	printf("    -m <dest-MAC> Used in sending the IP Tunneled pkt\n");
 	printf("    -T <stop-after-X-seconds> Default: 0 (forever)\n");
 	printf("    -P <IP-Protocol> Default is TCP\n");
 	printf("    -S use skb-mode\n");
 	printf("    -N enforce native mode\n");
 	printf("    -F Force loading the XDP prog\n");
 	printf("    -h Display this help\n");
 }

 static int parse_ipstr(const char *ipstr, unsigned int *addr)
 {
 	if (inet_pton(AF_INET6, ipstr, addr) == 1) {
 		return AF_INET6;
 	} else if (inet_pton(AF_INET, ipstr, addr) == 1) {
 		addr[1] = addr[2] = addr[3] = 0;
 		return AF_INET;
 	}

 	fprintf(stderr, "%s is an invalid IP\n", ipstr);
 	return AF_UNSPEC;
 }

 static int parse_ports(const char *port_str, int *min_port, int *max_port)
 {
 	char *end;
 	long tmp_min_port;
 	long tmp_max_port;

 	tmp_min_port = strtol(optarg, &end, 10);
 	if (tmp_min_port < 1 || tmp_min_port > 65535) {
 		fprintf(stderr, "Invalid port(s):%s\n", optarg);
 		return 1;
 	}

 	if (*end == '-') {
 		end++;
 		tmp_max_port = strtol(end, NULL, 10);
 		if (tmp_max_port < 1 || tmp_max_port > 65535) {
 			fprintf(stderr, "Invalid port(s):%s\n", optarg);
 			return 1;
 		}
 	} else {
 		tmp_max_port = tmp_min_port;
 	}

 	if (tmp_min_port > tmp_max_port) {
 		fprintf(stderr, "Invalid port(s):%s\n", optarg);
 		return 1;
 	}

 	if (tmp_max_port - tmp_min_port + 1 > MAX_IPTNL_ENTRIES) {
 		fprintf(stderr, "Port range (%s) is larger than %u\n",
 			port_str, MAX_IPTNL_ENTRIES);
 		return 1;
 	}
 	*min_port = tmp_min_port;
 	*max_port = tmp_max_port;

 	return 0;
 }

 int main(int argc, char **argv)
 {
 	struct bpf_prog_load_attr prog_load_attr = {
 		.prog_type	= BPF_PROG_TYPE_XDP,
 	};
 	struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
 	int min_port = 0, max_port = 0, vip2tnl_map_fd;
 	const char *optstr = "i:a:p:s:d:m:T:P:FSNh";
 	unsigned char opt_flags[256] = {};
 	struct bpf_prog_info info = {};
 	__u32 info_len = sizeof(info);
 	unsigned int kill_after_s = 0;
 	struct iptnl_info tnl = {};
 	struct bpf_object *obj;
 	struct vip vip = {};
 	char filename[256];
 	int opt, prog_fd;
 	int i, err;

 	tnl.family = AF_UNSPEC;
 	vip.protocol = IPPROTO_TCP;

 	for (i = 0; i < strlen(optstr); i++)
 		if (optstr[i] != 'h' && 'a' <= optstr[i] && optstr[i] <= 'z')
 			opt_flags[(unsigned char)optstr[i]] = 1;

 	while ((opt = getopt(argc, argv, optstr)) != -1) {
 		unsigned short family;
 		unsigned int *v6;

 		switch (opt) {
 		case 'i':
 			ifindex = if_nametoindex(optarg);
 			if (!ifindex)
 				ifindex = atoi(optarg);
 			break;
 		case 'a':
 			vip.family = parse_ipstr(optarg, vip.daddr.v6);
 			if (vip.family == AF_UNSPEC)
 				return 1;
 			break;
 		case 'p':
 			if (parse_ports(optarg, &min_port, &max_port))
 				return 1;
 			break;
 		case 'P':
 			vip.protocol = atoi(optarg);
 			break;
 		case 's':
 		case 'd':
 			if (opt == 's')
 				v6 = tnl.saddr.v6;
 			else
 				v6 = tnl.daddr.v6;

 			family = parse_ipstr(optarg, v6);
 			if (family == AF_UNSPEC)
 				return 1;
 			if (tnl.family == AF_UNSPEC) {
 				tnl.family = family;
 			} else if (tnl.family != family) {
 				fprintf(stderr,
 					"The IP version of the src and dst addresses used in the IP encapsulation does not match\n");
 				return 1;
 			}
 			break;
 		case 'm':
 			if (!ether_aton_r(optarg,
 					  (struct ether_addr *)tnl.dmac)) {
 				fprintf(stderr, "Invalid mac address:%s\n",
 					optarg);
 				return 1;
 			}
 			break;
 		case 'T':
 			kill_after_s = atoi(optarg);
 			break;
 		case 'S':
 			xdp_flags |= XDP_FLAGS_SKB_MODE;
 			break;
 		case 'N':
 			/* default, set below */
 			break;
 		case 'F':
 			xdp_flags &= ~XDP_FLAGS_UPDATE_IF_NOEXIST;
 			break;
 		default:
 			usage(argv[0]);
 			return 1;
 		}
 		opt_flags[opt] = 0;
 	}

 	if (!(xdp_flags & XDP_FLAGS_SKB_MODE))
 		xdp_flags |= XDP_FLAGS_DRV_MODE;

 	for (i = 0; i < strlen(optstr); i++) {
 		if (opt_flags[(unsigned int)optstr[i]]) {
 			fprintf(stderr, "Missing argument -%c\n", optstr[i]);
 			usage(argv[0]);
 			return 1;
 		}
 	}

 	if (setrlimit(RLIMIT_MEMLOCK, &r)) {
 		perror("setrlimit(RLIMIT_MEMLOCK, RLIM_INFINITY)");
 		return 1;
 	}

 	if (!ifindex) {
 		fprintf(stderr, "Invalid ifname\n");
 		return 1;
 	}

 	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 (!prog_fd) {
 		printf("bpf_prog_load_xattr: %s\n", strerror(errno));
 		return 1;
 	}

 	rxcnt_map_fd = bpf_object__find_map_fd_by_name(obj, "rxcnt");
 	vip2tnl_map_fd = bpf_object__find_map_fd_by_name(obj, "vip2tnl");
 	if (vip2tnl_map_fd < 0 || rxcnt_map_fd < 0) {
 		printf("bpf_object__find_map_fd_by_name failed\n");
 		return 1;
 	}

 	signal(SIGINT, int_exit);
 	signal(SIGTERM, int_exit);

 	while (min_port <= max_port) {
 		vip.dport = htons(min_port++);
 		if (bpf_map_update_elem(vip2tnl_map_fd, &vip, &tnl,
 					BPF_NOEXIST)) {
 			perror("bpf_map_update_elem(&vip2tnl)");
 			return 1;
 		}
 	}

 	if (bpf_set_link_xdp_fd(ifindex, prog_fd, xdp_flags) < 0) {
 		printf("link set xdp fd failed\n");
 		return 1;
 	}

 	err = bpf_obj_get_info_by_fd(prog_fd, &info, &info_len);
 	if (err) {
 		printf("can't get prog info - %s\n", strerror(errno));
 		return err;
 	}
 	prog_id = info.id;

 	poll_stats(kill_after_s);

 	bpf_set_link_xdp_fd(ifindex, -1, xdp_flags);

 	return 0;
 }
	// SPDX-License-Identifier: GPL-2.0-only
	/* Copyright (c) 2016 Facebook
	*/
	#include <linux/bpf.h>
	#include <linux/if_link.h>
	#include <assert.h>
	#include <errno.h>
	#include <signal.h>
	#include <stdio.h>
	#include <stdlib.h>
	#include <string.h>
	#include <net/if.h>
	#include <sys/resource.h>
	#include <arpa/inet.h>
	#include <netinet/ether.h>
	#include <unistd.h>
	#include <time.h>
	#include <bpf/libbpf.h>
	#include <bpf/bpf.h>
	#include "bpf_util.h"
	#include "xdp_tx_iptunnel_common.h"

	#define STATS_INTERVAL_S 2U

	static int ifindex = -1;
	static __u32 xdp_flags = XDP_FLAGS_UPDATE_IF_NOEXIST;
	static int rxcnt_map_fd;
	static __u32 prog_id;

	static void int_exit(int sig)
	{
	__u32 curr_prog_id = 0;

	if (ifindex > -1) {
	if (bpf_get_link_xdp_id(ifindex, &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, -1, xdp_flags);
	else if (!curr_prog_id)
	printf("couldn't find a prog id on a given iface\n");
	else
	printf("program on interface changed, not removing\n");
	}
	exit(0);
	}

	/* simple per-protocol drop counter
	*/
	static void poll_stats(unsigned int kill_after_s)
	{
	const unsigned int nr_protos = 256;
	unsigned int nr_cpus = bpf_num_possible_cpus();
	time_t started_at = time(NULL);
	__u64 values[nr_cpus], prev[nr_protos][nr_cpus];
	__u32 proto;
	int i;

	memset(prev, 0, sizeof(prev));

	while (!kill_after_s \|\| time(NULL) - started_at <= kill_after_s) {
	sleep(STATS_INTERVAL_S);

	for (proto = 0; proto < nr_protos; proto++) {
	__u64 sum = 0;

	assert(bpf_map_lookup_elem(rxcnt_map_fd, &proto,
	values) == 0);
	for (i = 0; i < nr_cpus; i++)
	sum += (values[i] - prev[proto][i]);

	if (sum)
	printf("proto %u: sum:%10llu pkts, rate:%10llu pkts/s\n",
	proto, sum, sum / STATS_INTERVAL_S);
	memcpy(prev[proto], values, sizeof(values));
	}
	}
	}

	static void usage(const char *cmd)
	{
	printf("Start a XDP prog which encapsulates incoming packets\n"
	"in an IPv4/v6 header and XDP_TX it out. The dst <VIP:PORT>\n"
	"is used to select packets to encapsulate\n\n");
	printf("Usage: %s [...]\n", cmd);
	printf(" -i <ifname\|ifindex> Interface\n");
	printf(" -a <vip-service-address> IPv4 or IPv6\n");
	printf(" -p <vip-service-port> A port range (e.g. 433-444) is also allowed\n");
	printf(" -s <source-ip> Used in the IPTunnel header\n");
	printf(" -d <dest-ip> Used in the IPTunnel header\n");
	printf(" -m <dest-MAC> Used in sending the IP Tunneled pkt\n");
	printf(" -T <stop-after-X-seconds> Default: 0 (forever)\n");
	printf(" -P <IP-Protocol> Default is TCP\n");
	printf(" -S use skb-mode\n");
	printf(" -N enforce native mode\n");
	printf(" -F Force loading the XDP prog\n");
	printf(" -h Display this help\n");
	}

	static int parse_ipstr(const char ipstr, unsigned int addr)
	{
	if (inet_pton(AF_INET6, ipstr, addr) == 1) {
	return AF_INET6;
	} else if (inet_pton(AF_INET, ipstr, addr) == 1) {
	addr[1] = addr[2] = addr[3] = 0;
	return AF_INET;
	}

	fprintf(stderr, "%s is an invalid IP\n", ipstr);
	return AF_UNSPEC;
	}

	static int parse_ports(const char port_str, int min_port, int *max_port)
	{
	char *end;
	long tmp_min_port;
	long tmp_max_port;

	tmp_min_port = strtol(optarg, &end, 10);
	if (tmp_min_port < 1 \|\| tmp_min_port > 65535) {
	fprintf(stderr, "Invalid port(s):%s\n", optarg);
	return 1;
	}

	if (*end == '-') {
	end++;
	tmp_max_port = strtol(end, NULL, 10);
	if (tmp_max_port < 1 \|\| tmp_max_port > 65535) {
	fprintf(stderr, "Invalid port(s):%s\n", optarg);
	return 1;
	}
	} else {
	tmp_max_port = tmp_min_port;
	}

	if (tmp_min_port > tmp_max_port) {
	fprintf(stderr, "Invalid port(s):%s\n", optarg);
	return 1;
	}

	if (tmp_max_port - tmp_min_port + 1 > MAX_IPTNL_ENTRIES) {
	fprintf(stderr, "Port range (%s) is larger than %u\n",
	port_str, MAX_IPTNL_ENTRIES);
	return 1;
	}
	*min_port = tmp_min_port;
	*max_port = tmp_max_port;

	return 0;
	}

	int main(int argc, char **argv)
	{
	struct bpf_prog_load_attr prog_load_attr = {
	.prog_type = BPF_PROG_TYPE_XDP,
	};
	struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
	int min_port = 0, max_port = 0, vip2tnl_map_fd;
	const char *optstr = "i:a:p:s:d:m:T:P:FSNh";
	unsigned char opt_flags[256] = {};
	struct bpf_prog_info info = {};
	__u32 info_len = sizeof(info);
	unsigned int kill_after_s = 0;
	struct iptnl_info tnl = {};
	struct bpf_object *obj;
	struct vip vip = {};
	char filename[256];
	int opt, prog_fd;
	int i, err;

	tnl.family = AF_UNSPEC;
	vip.protocol = IPPROTO_TCP;

	for (i = 0; i < strlen(optstr); i++)
	if (optstr[i] != 'h' && 'a' <= optstr[i] && optstr[i] <= 'z')
	opt_flags[(unsigned char)optstr[i]] = 1;

	while ((opt = getopt(argc, argv, optstr)) != -1) {
	unsigned short family;
	unsigned int *v6;

	switch (opt) {
	case 'i':
	ifindex = if_nametoindex(optarg);
	if (!ifindex)
	ifindex = atoi(optarg);
	break;
	case 'a':
	vip.family = parse_ipstr(optarg, vip.daddr.v6);
	if (vip.family == AF_UNSPEC)
	return 1;
	break;
	case 'p':
	if (parse_ports(optarg, &min_port, &max_port))
	return 1;
	break;
	case 'P':
	vip.protocol = atoi(optarg);
	break;
	case 's':
	case 'd':
	if (opt == 's')
	v6 = tnl.saddr.v6;
	else
	v6 = tnl.daddr.v6;

	family = parse_ipstr(optarg, v6);
	if (family == AF_UNSPEC)
	return 1;
	if (tnl.family == AF_UNSPEC) {
	tnl.family = family;
	} else if (tnl.family != family) {
	fprintf(stderr,
	"The IP version of the src and dst addresses used in the IP encapsulation does not match\n");
	return 1;
	}
	break;
	case 'm':
	if (!ether_aton_r(optarg,
	(struct ether_addr *)tnl.dmac)) {
	fprintf(stderr, "Invalid mac address:%s\n",
	optarg);
	return 1;
	}
	break;
	case 'T':
	kill_after_s = atoi(optarg);
	break;
	case 'S':
	xdp_flags \|= XDP_FLAGS_SKB_MODE;
	break;
	case 'N':
	/* default, set below */
	break;
	case 'F':
	xdp_flags &= ~XDP_FLAGS_UPDATE_IF_NOEXIST;
	break;
	default:
	usage(argv[0]);
	return 1;
	}
	opt_flags[opt] = 0;
	}

	if (!(xdp_flags & XDP_FLAGS_SKB_MODE))
	xdp_flags \|= XDP_FLAGS_DRV_MODE;

	for (i = 0; i < strlen(optstr); i++) {
	if (opt_flags[(unsigned int)optstr[i]]) {
	fprintf(stderr, "Missing argument -%c\n", optstr[i]);
	usage(argv[0]);
	return 1;
	}
	}

	if (setrlimit(RLIMIT_MEMLOCK, &r)) {
	perror("setrlimit(RLIMIT_MEMLOCK, RLIM_INFINITY)");
	return 1;
	}

	if (!ifindex) {
	fprintf(stderr, "Invalid ifname\n");
	return 1;
	}

	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 (!prog_fd) {
	printf("bpf_prog_load_xattr: %s\n", strerror(errno));
	return 1;
	}

	rxcnt_map_fd = bpf_object__find_map_fd_by_name(obj, "rxcnt");
	vip2tnl_map_fd = bpf_object__find_map_fd_by_name(obj, "vip2tnl");
	if (vip2tnl_map_fd < 0 \|\| rxcnt_map_fd < 0) {
	printf("bpf_object__find_map_fd_by_name failed\n");
	return 1;
	}

	signal(SIGINT, int_exit);
	signal(SIGTERM, int_exit);

	while (min_port <= max_port) {
	vip.dport = htons(min_port++);
	if (bpf_map_update_elem(vip2tnl_map_fd, &vip, &tnl,
	BPF_NOEXIST)) {
	perror("bpf_map_update_elem(&vip2tnl)");
	return 1;
	}
	}

	if (bpf_set_link_xdp_fd(ifindex, prog_fd, xdp_flags) < 0) {
	printf("link set xdp fd failed\n");
	return 1;
	}

	err = bpf_obj_get_info_by_fd(prog_fd, &info, &info_len);
	if (err) {
	printf("can't get prog info - %s\n", strerror(errno));
	return err;
	}
	prog_id = info.id;

	poll_stats(kill_after_s);

	bpf_set_link_xdp_fd(ifindex, -1, xdp_flags);

	return 0;
	}