samples/bpf/xdp_tx_iptunnel_user.c

   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 <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
  27 static int ifindex = -1;
  28 static __u32 xdp_flags = 0;
  29
  30 static void int_exit(int sig)
  31 {
  32         if (ifindex > -1)
  33                 set_link_xdp_fd(ifindex, -1, xdp_flags);
  34         exit(0);
  35 }
  36
  37 /* simple per-protocol drop counter
  38  */
  39 static 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
  68 static 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("    -h Display this help\n");
  83 }
  84
  85 static int parse_ipstr(const char *ipstr, unsigned int *addr)
  86 {
  87         if (inet_pton(AF_INET6, ipstr, addr) == 1) {
  88                 return AF_INET6;
  89         } else if (inet_pton(AF_INET, ipstr, addr) == 1) {
  90                 addr[1] = addr[2] = addr[3] = 0;
  91                 return AF_INET;
  92         }
  93
  94         fprintf(stderr, "%s is an invalid IP\n", ipstr);
  95         return AF_UNSPEC;
  96 }
  97
  98 static int parse_ports(const char *port_str, int *min_port, int *max_port)
  99 {
 100         char *end;
 101         long tmp_min_port;
 102         long tmp_max_port;
 103
 104         tmp_min_port = strtol(optarg, &end, 10);
 105         if (tmp_min_port < 1 || tmp_min_port > 65535) {
 106                 fprintf(stderr, "Invalid port(s):%s\n", optarg);
 107                 return 1;
 108         }
 109
 110         if (*end == '-') {
 111                 end++;
 112                 tmp_max_port = strtol(end, NULL, 10);
 113                 if (tmp_max_port < 1 || tmp_max_port > 65535) {
 114                         fprintf(stderr, "Invalid port(s):%s\n", optarg);
 115                         return 1;
 116                 }
 117         } else {
 118                 tmp_max_port = tmp_min_port;
 119         }
 120
 121         if (tmp_min_port > tmp_max_port) {
 122                 fprintf(stderr, "Invalid port(s):%s\n", optarg);
 123                 return 1;
 124         }
 125
 126         if (tmp_max_port - tmp_min_port + 1 > MAX_IPTNL_ENTRIES) {
 127                 fprintf(stderr, "Port range (%s) is larger than %u\n",
 128                         port_str, MAX_IPTNL_ENTRIES);
 129                 return 1;
 130         }
 131         *min_port = tmp_min_port;
 132         *max_port = tmp_max_port;
 133
 134         return 0;
 135 }
 136
 137 int main(int argc, char **argv)
 138 {
 139         unsigned char opt_flags[256] = {};
 140         unsigned int kill_after_s = 0;
 141         const char *optstr = "i:a:p:s:d:m:T:P:Sh";
 142         int min_port = 0, max_port = 0;
 143         struct iptnl_info tnl = {};
 144         struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
 145         struct vip vip = {};
 146         char filename[256];
 147         int opt;
 148         int i;
 149
 150         tnl.family = AF_UNSPEC;
 151         vip.protocol = IPPROTO_TCP;
 152
 153         for (i = 0; i < strlen(optstr); i++)
 154                 if (optstr[i] != 'h' && 'a' <= optstr[i] && optstr[i] <= 'z')
 155                         opt_flags[(unsigned char)optstr[i]] = 1;
 156
 157         while ((opt = getopt(argc, argv, optstr)) != -1) {
 158                 unsigned short family;
 159                 unsigned int *v6;
 160
 161                 switch (opt) {
 162                 case 'i':
 163                         ifindex = atoi(optarg);
 164                         break;
 165                 case 'a':
 166                         vip.family = parse_ipstr(optarg, vip.daddr.v6);
 167                         if (vip.family == AF_UNSPEC)
 168                                 return 1;
 169                         break;
 170                 case 'p':
 171                         if (parse_ports(optarg, &min_port, &max_port))
 172                                 return 1;
 173                         break;
 174                 case 'P':
 175                         vip.protocol = atoi(optarg);
 176                         break;
 177                 case 's':
 178                 case 'd':
 179                         if (opt == 's')
 180                                 v6 = tnl.saddr.v6;
 181                         else
 182                                 v6 = tnl.daddr.v6;
 183
 184                         family = parse_ipstr(optarg, v6);
 185                         if (family == AF_UNSPEC)
 186                                 return 1;
 187                         if (tnl.family == AF_UNSPEC) {
 188                                 tnl.family = family;
 189                         } else if (tnl.family != family) {
 190                                 fprintf(stderr,
 191                                         "The IP version of the src and dst addresses used in the IP encapsulation does not match\n");
 192                                 return 1;
 193                         }
 194                         break;
 195                 case 'm':
 196                         if (!ether_aton_r(optarg,
 197                                           (struct ether_addr *)tnl.dmac)) {
 198                                 fprintf(stderr, "Invalid mac address:%s\n",
 199                                         optarg);
 200                                 return 1;
 201                         }
 202                         break;
 203                 case 'T':
 204                         kill_after_s = atoi(optarg);
 205                         break;
 206                 case 'S':
 207                         xdp_flags |= XDP_FLAGS_SKB_MODE;
 208                         break;
 209                 default:
 210                         usage(argv[0]);
 211                         return 1;
 212                 }
 213                 opt_flags[opt] = 0;
 214         }
 215
 216         for (i = 0; i < strlen(optstr); i++) {
 217                 if (opt_flags[(unsigned int)optstr[i]]) {
 218                         fprintf(stderr, "Missing argument -%c\n", optstr[i]);
 219                         usage(argv[0]);
 220                         return 1;
 221                 }
 222         }
 223
 224         if (setrlimit(RLIMIT_MEMLOCK, &r)) {
 225                 perror("setrlimit(RLIMIT_MEMLOCK, RLIM_INFINITY)");
 226                 return 1;
 227         }
 228
 229         snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
 230
 231         if (load_bpf_file(filename)) {
 232                 printf("%s", bpf_log_buf);
 233                 return 1;
 234         }
 235
 236         if (!prog_fd[0]) {
 237                 printf("load_bpf_file: %s\n", strerror(errno));
 238                 return 1;
 239         }
 240
 241         signal(SIGINT, int_exit);
 242
 243         while (min_port <= max_port) {
 244                 vip.dport = htons(min_port++);
 245                 if (bpf_map_update_elem(map_fd[1], &vip, &tnl, BPF_NOEXIST)) {
 246                         perror("bpf_map_update_elem(&vip2tnl)");
 247                         return 1;
 248                 }
 249         }
 250
 251         if (set_link_xdp_fd(ifindex, prog_fd[0], xdp_flags) < 0) {
 252                 printf("link set xdp fd failed\n");
 253                 return 1;
 254         }
 255
 256         poll_stats(kill_after_s);
 257
 258         set_link_xdp_fd(ifindex, -1, xdp_flags);
 259
 260         return 0;
 261 }