1/* Copyright (c) 2016 Facebook
  2 *
  3 * This program is free software; you can redistribute it and/or
  4 * modify it under the terms of version 2 of the GNU General Public
  5 * License as published by the Free Software Foundation.
  6 */
  7#include <linux/bpf.h>
  8#include <assert.h>
  9#include <errno.h>
 10#include <signal.h>
 11#include <stdio.h>
 12#include <stdlib.h>
 13#include <string.h>
 14#include <sys/resource.h>
 15#include <arpa/inet.h>
 16#include <netinet/ether.h>
 17#include <unistd.h>
 18#include <time.h>
 19#include "bpf_load.h"
 20#include "libbpf.h"
 21#include "bpf_util.h"
 22#include "xdp_tx_iptunnel_common.h"
 23
 24#define STATS_INTERVAL_S 2U
 25
 26static int ifindex = -1;
 27
 28static void int_exit(int sig)
 29{
 30	if (ifindex > -1)
 31		set_link_xdp_fd(ifindex, -1);
 32	exit(0);
 33}
 34
 35/* simple per-protocol drop counter
 36 */
 37static void poll_stats(unsigned int kill_after_s)
 38{
 39	const unsigned int nr_protos = 256;
 40	unsigned int nr_cpus = bpf_num_possible_cpus();
 41	time_t started_at = time(NULL);
 42	__u64 values[nr_cpus], prev[nr_protos][nr_cpus];
 43	__u32 proto;
 44	int i;
 45
 46	memset(prev, 0, sizeof(prev));
 47
 48	while (!kill_after_s || time(NULL) - started_at <= kill_after_s) {
 49		sleep(STATS_INTERVAL_S);
 50
 51		for (proto = 0; proto < nr_protos; proto++) {
 52			__u64 sum = 0;
 53
 54			assert(bpf_map_lookup_elem(map_fd[0], &proto, values) == 0);
 55			for (i = 0; i < nr_cpus; i++)
 56				sum += (values[i] - prev[proto][i]);
 57
 58			if (sum)
 59				printf("proto %u: sum:%10llu pkts, rate:%10llu pkts/s\n",
 60				       proto, sum, sum / STATS_INTERVAL_S);
 61			memcpy(prev[proto], values, sizeof(values));
 62		}
 63	}
 64}
 65
 66static void usage(const char *cmd)
 67{
 68	printf("Start a XDP prog which encapsulates incoming packets\n"
 69	       "in an IPv4/v6 header and XDP_TX it out.  The dst <VIP:PORT>\n"
 70	       "is used to select packets to encapsulate\n\n");
 71	printf("Usage: %s [...]\n", cmd);
 72	printf("    -i <ifindex> Interface Index\n");
 73	printf("    -a <vip-service-address> IPv4 or IPv6\n");
 74	printf("    -p <vip-service-port> A port range (e.g. 433-444) is also allowed\n");
 75	printf("    -s <source-ip> Used in the IPTunnel header\n");
 76	printf("    -d <dest-ip> Used in the IPTunnel header\n");
 77	printf("    -m <dest-MAC> Used in sending the IP Tunneled pkt\n");
 78	printf("    -T <stop-after-X-seconds> Default: 0 (forever)\n");
 79	printf("    -P <IP-Protocol> Default is TCP\n");
 80	printf("    -h Display this help\n");
 81}
 82
 83static int parse_ipstr(const char *ipstr, unsigned int *addr)
 84{
 85	if (inet_pton(AF_INET6, ipstr, addr) == 1) {
 86		return AF_INET6;
 87	} else if (inet_pton(AF_INET, ipstr, addr) == 1) {
 88		addr[1] = addr[2] = addr[3] = 0;
 89		return AF_INET;
 90	}
 91
 92	fprintf(stderr, "%s is an invalid IP\n", ipstr);
 93	return AF_UNSPEC;
 94}
 95
 96static int parse_ports(const char *port_str, int *min_port, int *max_port)
 97{
 98	char *end;
 99	long tmp_min_port;
100	long tmp_max_port;
101
102	tmp_min_port = strtol(optarg, &end, 10);
103	if (tmp_min_port < 1 || tmp_min_port > 65535) {
104		fprintf(stderr, "Invalid port(s):%s\n", optarg);
105		return 1;
106	}
107
108	if (*end == '-') {
109		end++;
110		tmp_max_port = strtol(end, NULL, 10);
111		if (tmp_max_port < 1 || tmp_max_port > 65535) {
112			fprintf(stderr, "Invalid port(s):%s\n", optarg);
113			return 1;
114		}
115	} else {
116		tmp_max_port = tmp_min_port;
117	}
118
119	if (tmp_min_port > tmp_max_port) {
120		fprintf(stderr, "Invalid port(s):%s\n", optarg);
121		return 1;
122	}
123
124	if (tmp_max_port - tmp_min_port + 1 > MAX_IPTNL_ENTRIES) {
125		fprintf(stderr, "Port range (%s) is larger than %u\n",
126			port_str, MAX_IPTNL_ENTRIES);
127		return 1;
128	}
129	*min_port = tmp_min_port;
130	*max_port = tmp_max_port;
131
132	return 0;
133}
134
135int main(int argc, char **argv)
136{
137	unsigned char opt_flags[256] = {};
138	unsigned int kill_after_s = 0;
139	const char *optstr = "i:a:p:s:d:m:T:P:h";
140	int min_port = 0, max_port = 0;
141	struct iptnl_info tnl = {};
142	struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
143	struct vip vip = {};
144	char filename[256];
145	int opt;
146	int i;
147
148	tnl.family = AF_UNSPEC;
149	vip.protocol = IPPROTO_TCP;
150
151	for (i = 0; i < strlen(optstr); i++)
152		if (optstr[i] != 'h' && 'a' <= optstr[i] && optstr[i] <= 'z')
153			opt_flags[(unsigned char)optstr[i]] = 1;
154
155	while ((opt = getopt(argc, argv, optstr)) != -1) {
156		unsigned short family;
157		unsigned int *v6;
158
159		switch (opt) {
160		case 'i':
161			ifindex = atoi(optarg);
162			break;
163		case 'a':
164			vip.family = parse_ipstr(optarg, vip.daddr.v6);
165			if (vip.family == AF_UNSPEC)
166				return 1;
167			break;
168		case 'p':
169			if (parse_ports(optarg, &min_port, &max_port))
170				return 1;
171			break;
172		case 'P':
173			vip.protocol = atoi(optarg);
174			break;
175		case 's':
176		case 'd':
177			if (opt == 's')
178				v6 = tnl.saddr.v6;
179			else
180				v6 = tnl.daddr.v6;
181
182			family = parse_ipstr(optarg, v6);
183			if (family == AF_UNSPEC)
184				return 1;
185			if (tnl.family == AF_UNSPEC) {
186				tnl.family = family;
187			} else if (tnl.family != family) {
188				fprintf(stderr,
189					"The IP version of the src and dst addresses used in the IP encapsulation does not match\n");
190				return 1;
191			}
192			break;
193		case 'm':
194			if (!ether_aton_r(optarg,
195					  (struct ether_addr *)tnl.dmac)) {
196				fprintf(stderr, "Invalid mac address:%s\n",
197					optarg);
198				return 1;
199			}
200			break;
201		case 'T':
202			kill_after_s = atoi(optarg);
203			break;
204		default:
205			usage(argv[0]);
206			return 1;
207		}
208		opt_flags[opt] = 0;
209	}
210
211	for (i = 0; i < strlen(optstr); i++) {
212		if (opt_flags[(unsigned int)optstr[i]]) {
213			fprintf(stderr, "Missing argument -%c\n", optstr[i]);
214			usage(argv[0]);
215			return 1;
216		}
217	}
218
219	if (setrlimit(RLIMIT_MEMLOCK, &r)) {
220		perror("setrlimit(RLIMIT_MEMLOCK, RLIM_INFINITY)");
221		return 1;
222	}
223
224	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
225
226	if (load_bpf_file(filename)) {
227		printf("%s", bpf_log_buf);
228		return 1;
229	}
230
231	if (!prog_fd[0]) {
232		printf("load_bpf_file: %s\n", strerror(errno));
233		return 1;
234	}
235
236	signal(SIGINT, int_exit);
237
238	while (min_port <= max_port) {
239		vip.dport = htons(min_port++);
240		if (bpf_map_update_elem(map_fd[1], &vip, &tnl, BPF_NOEXIST)) {
241			perror("bpf_map_update_elem(&vip2tnl)");
242			return 1;
243		}
244	}
245
246	if (set_link_xdp_fd(ifindex, prog_fd[0]) < 0) {
247		printf("link set xdp fd failed\n");
248		return 1;
249	}
250
251	poll_stats(kill_after_s);
252
253	set_link_xdp_fd(ifindex, -1);
254
255	return 0;
256}