1
2
3
4
5
6
7#include <linux/bpf.h>
8#include <linux/if_link.h>
9#include <assert.h>
10#include <errno.h>
11#include <signal.h>
12#include <stdio.h>
13#include <stdlib.h>
14#include <string.h>
15#include <sys/resource.h>
16#include <arpa/inet.h>
17#include <netinet/ether.h>
18#include <unistd.h>
19#include <time.h>
20#include "bpf_load.h"
21#include "libbpf.h"
22#include "bpf_util.h"
23#include "xdp_tx_iptunnel_common.h"
24
25#define STATS_INTERVAL_S 2U
26
27static int ifindex = -1;
28static __u32 xdp_flags = 0;
29
30static void int_exit(int sig)
31{
32 if (ifindex > -1)
33 bpf_set_link_xdp_fd(ifindex, -1, xdp_flags);
34 exit(0);
35}
36
37
38
39static void poll_stats(unsigned int kill_after_s)
40{
41 const unsigned int nr_protos = 256;
42 unsigned int nr_cpus = bpf_num_possible_cpus();
43 time_t started_at = time(NULL);
44 __u64 values[nr_cpus], prev[nr_protos][nr_cpus];
45 __u32 proto;
46 int i;
47
48 memset(prev, 0, sizeof(prev));
49
50 while (!kill_after_s || time(NULL) - started_at <= kill_after_s) {
51 sleep(STATS_INTERVAL_S);
52
53 for (proto = 0; proto < nr_protos; proto++) {
54 __u64 sum = 0;
55
56 assert(bpf_map_lookup_elem(map_fd[0], &proto, values) == 0);
57 for (i = 0; i < nr_cpus; i++)
58 sum += (values[i] - prev[proto][i]);
59
60 if (sum)
61 printf("proto %u: sum:%10llu pkts, rate:%10llu pkts/s\n",
62 proto, sum, sum / STATS_INTERVAL_S);
63 memcpy(prev[proto], values, sizeof(values));
64 }
65 }
66}
67
68static void usage(const char *cmd)
69{
70 printf("Start a XDP prog which encapsulates incoming packets\n"
71 "in an IPv4/v6 header and XDP_TX it out. The dst <VIP:PORT>\n"
72 "is used to select packets to encapsulate\n\n");
73 printf("Usage: %s [...]\n", cmd);
74 printf(" -i <ifindex> Interface Index\n");
75 printf(" -a <vip-service-address> IPv4 or IPv6\n");
76 printf(" -p <vip-service-port> A port range (e.g. 433-444) is also allowed\n");
77 printf(" -s <source-ip> Used in the IPTunnel header\n");
78 printf(" -d <dest-ip> Used in the IPTunnel header\n");
79 printf(" -m <dest-MAC> Used in sending the IP Tunneled pkt\n");
80 printf(" -T <stop-after-X-seconds> Default: 0 (forever)\n");
81 printf(" -P <IP-Protocol> Default is TCP\n");
82 printf(" -S use skb-mode\n");
83 printf(" -N enforce native mode\n");
84 printf(" -h Display this help\n");
85}
86
87static int parse_ipstr(const char *ipstr, unsigned int *addr)
88{
89 if (inet_pton(AF_INET6, ipstr, addr) == 1) {
90 return AF_INET6;
91 } else if (inet_pton(AF_INET, ipstr, addr) == 1) {
92 addr[1] = addr[2] = addr[3] = 0;
93 return AF_INET;
94 }
95
96 fprintf(stderr, "%s is an invalid IP\n", ipstr);
97 return AF_UNSPEC;
98}
99
100static int parse_ports(const char *port_str, int *min_port, int *max_port)
101{
102 char *end;
103 long tmp_min_port;
104 long tmp_max_port;
105
106 tmp_min_port = strtol(optarg, &end, 10);
107 if (tmp_min_port < 1 || tmp_min_port > 65535) {
108 fprintf(stderr, "Invalid port(s):%s\n", optarg);
109 return 1;
110 }
111
112 if (*end == '-') {
113 end++;
114 tmp_max_port = strtol(end, NULL, 10);
115 if (tmp_max_port < 1 || tmp_max_port > 65535) {
116 fprintf(stderr, "Invalid port(s):%s\n", optarg);
117 return 1;
118 }
119 } else {
120 tmp_max_port = tmp_min_port;
121 }
122
123 if (tmp_min_port > tmp_max_port) {
124 fprintf(stderr, "Invalid port(s):%s\n", optarg);
125 return 1;
126 }
127
128 if (tmp_max_port - tmp_min_port + 1 > MAX_IPTNL_ENTRIES) {
129 fprintf(stderr, "Port range (%s) is larger than %u\n",
130 port_str, MAX_IPTNL_ENTRIES);
131 return 1;
132 }
133 *min_port = tmp_min_port;
134 *max_port = tmp_max_port;
135
136 return 0;
137}
138
139int main(int argc, char **argv)
140{
141 unsigned char opt_flags[256] = {};
142 unsigned int kill_after_s = 0;
143 const char *optstr = "i:a:p:s:d:m:T:P:SNh";
144 int min_port = 0, max_port = 0;
145 struct iptnl_info tnl = {};
146 struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
147 struct vip vip = {};
148 char filename[256];
149 int opt;
150 int i;
151
152 tnl.family = AF_UNSPEC;
153 vip.protocol = IPPROTO_TCP;
154
155 for (i = 0; i < strlen(optstr); i++)
156 if (optstr[i] != 'h' && 'a' <= optstr[i] && optstr[i] <= 'z')
157 opt_flags[(unsigned char)optstr[i]] = 1;
158
159 while ((opt = getopt(argc, argv, optstr)) != -1) {
160 unsigned short family;
161 unsigned int *v6;
162
163 switch (opt) {
164 case 'i':
165 ifindex = atoi(optarg);
166 break;
167 case 'a':
168 vip.family = parse_ipstr(optarg, vip.daddr.v6);
169 if (vip.family == AF_UNSPEC)
170 return 1;
171 break;
172 case 'p':
173 if (parse_ports(optarg, &min_port, &max_port))
174 return 1;
175 break;
176 case 'P':
177 vip.protocol = atoi(optarg);
178 break;
179 case 's':
180 case 'd':
181 if (opt == 's')
182 v6 = tnl.saddr.v6;
183 else
184 v6 = tnl.daddr.v6;
185
186 family = parse_ipstr(optarg, v6);
187 if (family == AF_UNSPEC)
188 return 1;
189 if (tnl.family == AF_UNSPEC) {
190 tnl.family = family;
191 } else if (tnl.family != family) {
192 fprintf(stderr,
193 "The IP version of the src and dst addresses used in the IP encapsulation does not match\n");
194 return 1;
195 }
196 break;
197 case 'm':
198 if (!ether_aton_r(optarg,
199 (struct ether_addr *)tnl.dmac)) {
200 fprintf(stderr, "Invalid mac address:%s\n",
201 optarg);
202 return 1;
203 }
204 break;
205 case 'T':
206 kill_after_s = atoi(optarg);
207 break;
208 case 'S':
209 xdp_flags |= XDP_FLAGS_SKB_MODE;
210 break;
211 case 'N':
212 xdp_flags |= XDP_FLAGS_DRV_MODE;
213 break;
214 default:
215 usage(argv[0]);
216 return 1;
217 }
218 opt_flags[opt] = 0;
219 }
220
221 for (i = 0; i < strlen(optstr); i++) {
222 if (opt_flags[(unsigned int)optstr[i]]) {
223 fprintf(stderr, "Missing argument -%c\n", optstr[i]);
224 usage(argv[0]);
225 return 1;
226 }
227 }
228
229 if (setrlimit(RLIMIT_MEMLOCK, &r)) {
230 perror("setrlimit(RLIMIT_MEMLOCK, RLIM_INFINITY)");
231 return 1;
232 }
233
234 snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
235
236 if (load_bpf_file(filename)) {
237 printf("%s", bpf_log_buf);
238 return 1;
239 }
240
241 if (!prog_fd[0]) {
242 printf("load_bpf_file: %s\n", strerror(errno));
243 return 1;
244 }
245
246 signal(SIGINT, int_exit);
247 signal(SIGTERM, int_exit);
248
249 while (min_port <= max_port) {
250 vip.dport = htons(min_port++);
251 if (bpf_map_update_elem(map_fd[1], &vip, &tnl, BPF_NOEXIST)) {
252 perror("bpf_map_update_elem(&vip2tnl)");
253 return 1;
254 }
255 }
256
257 if (bpf_set_link_xdp_fd(ifindex, prog_fd[0], xdp_flags) < 0) {
258 printf("link set xdp fd failed\n");
259 return 1;
260 }
261
262 poll_stats(kill_after_s);
263
264 bpf_set_link_xdp_fd(ifindex, -1, xdp_flags);
265
266 return 0;
267}
268
