311 lines · c
1// SPDX-License-Identifier: GPL-2.0-only2/* Copyright (c) 2016 Facebook3 */4#include <linux/bpf.h>5#include <linux/if_link.h>6#include <assert.h>7#include <errno.h>8#include <signal.h>9#include <stdio.h>10#include <stdlib.h>11#include <string.h>12#include <net/if.h>13#include <arpa/inet.h>14#include <netinet/ether.h>15#include <unistd.h>16#include <time.h>17#include <bpf/libbpf.h>18#include <bpf/bpf.h>19#include "bpf_util.h"20#include "xdp_tx_iptunnel_common.h"21 22#define STATS_INTERVAL_S 2U23 24static int ifindex = -1;25static __u32 xdp_flags = XDP_FLAGS_UPDATE_IF_NOEXIST;26static int rxcnt_map_fd;27static __u32 prog_id;28 29static void int_exit(int sig)30{31 __u32 curr_prog_id = 0;32 33 if (ifindex > -1) {34 if (bpf_xdp_query_id(ifindex, xdp_flags, &curr_prog_id)) {35 printf("bpf_xdp_query_id failed\n");36 exit(1);37 }38 if (prog_id == curr_prog_id)39 bpf_xdp_detach(ifindex, xdp_flags, NULL);40 else if (!curr_prog_id)41 printf("couldn't find a prog id on a given iface\n");42 else43 printf("program on interface changed, not removing\n");44 }45 exit(0);46}47 48/* simple per-protocol drop counter49 */50static void poll_stats(unsigned int kill_after_s)51{52 const unsigned int nr_protos = 256;53 unsigned int nr_cpus = bpf_num_possible_cpus();54 time_t started_at = time(NULL);55 __u64 values[nr_cpus], prev[nr_protos][nr_cpus];56 __u32 proto;57 int i;58 59 memset(prev, 0, sizeof(prev));60 61 while (!kill_after_s || time(NULL) - started_at <= kill_after_s) {62 sleep(STATS_INTERVAL_S);63 64 for (proto = 0; proto < nr_protos; proto++) {65 __u64 sum = 0;66 67 assert(bpf_map_lookup_elem(rxcnt_map_fd, &proto,68 values) == 0);69 for (i = 0; i < nr_cpus; i++)70 sum += (values[i] - prev[proto][i]);71 72 if (sum)73 printf("proto %u: sum:%10llu pkts, rate:%10llu pkts/s\n",74 proto, sum, sum / STATS_INTERVAL_S);75 memcpy(prev[proto], values, sizeof(values));76 }77 }78}79 80static void usage(const char *cmd)81{82 printf("Start a XDP prog which encapsulates incoming packets\n"83 "in an IPv4/v6 header and XDP_TX it out. The dst <VIP:PORT>\n"84 "is used to select packets to encapsulate\n\n");85 printf("Usage: %s [...]\n", cmd);86 printf(" -i <ifname|ifindex> Interface\n");87 printf(" -a <vip-service-address> IPv4 or IPv6\n");88 printf(" -p <vip-service-port> A port range (e.g. 433-444) is also allowed\n");89 printf(" -s <source-ip> Used in the IPTunnel header\n");90 printf(" -d <dest-ip> Used in the IPTunnel header\n");91 printf(" -m <dest-MAC> Used in sending the IP Tunneled pkt\n");92 printf(" -T <stop-after-X-seconds> Default: 0 (forever)\n");93 printf(" -P <IP-Protocol> Default is TCP\n");94 printf(" -S use skb-mode\n");95 printf(" -N enforce native mode\n");96 printf(" -F Force loading the XDP prog\n");97 printf(" -h Display this help\n");98}99 100static int parse_ipstr(const char *ipstr, unsigned int *addr)101{102 if (inet_pton(AF_INET6, ipstr, addr) == 1) {103 return AF_INET6;104 } else if (inet_pton(AF_INET, ipstr, addr) == 1) {105 addr[1] = addr[2] = addr[3] = 0;106 return AF_INET;107 }108 109 fprintf(stderr, "%s is an invalid IP\n", ipstr);110 return AF_UNSPEC;111}112 113static int parse_ports(const char *port_str, int *min_port, int *max_port)114{115 char *end;116 long tmp_min_port;117 long tmp_max_port;118 119 tmp_min_port = strtol(optarg, &end, 10);120 if (tmp_min_port < 1 || tmp_min_port > 65535) {121 fprintf(stderr, "Invalid port(s):%s\n", optarg);122 return 1;123 }124 125 if (*end == '-') {126 end++;127 tmp_max_port = strtol(end, NULL, 10);128 if (tmp_max_port < 1 || tmp_max_port > 65535) {129 fprintf(stderr, "Invalid port(s):%s\n", optarg);130 return 1;131 }132 } else {133 tmp_max_port = tmp_min_port;134 }135 136 if (tmp_min_port > tmp_max_port) {137 fprintf(stderr, "Invalid port(s):%s\n", optarg);138 return 1;139 }140 141 if (tmp_max_port - tmp_min_port + 1 > MAX_IPTNL_ENTRIES) {142 fprintf(stderr, "Port range (%s) is larger than %u\n",143 port_str, MAX_IPTNL_ENTRIES);144 return 1;145 }146 *min_port = tmp_min_port;147 *max_port = tmp_max_port;148 149 return 0;150}151 152int main(int argc, char **argv)153{154 int min_port = 0, max_port = 0, vip2tnl_map_fd;155 const char *optstr = "i:a:p:s:d:m:T:P:FSNh";156 unsigned char opt_flags[256] = {};157 struct bpf_prog_info info = {};158 __u32 info_len = sizeof(info);159 unsigned int kill_after_s = 0;160 struct iptnl_info tnl = {};161 struct bpf_program *prog;162 struct bpf_object *obj;163 struct vip vip = {};164 char filename[256];165 int opt, prog_fd;166 int i, err;167 168 tnl.family = AF_UNSPEC;169 vip.protocol = IPPROTO_TCP;170 171 for (i = 0; i < strlen(optstr); i++)172 if (optstr[i] != 'h' && 'a' <= optstr[i] && optstr[i] <= 'z')173 opt_flags[(unsigned char)optstr[i]] = 1;174 175 while ((opt = getopt(argc, argv, optstr)) != -1) {176 unsigned short family;177 unsigned int *v6;178 179 switch (opt) {180 case 'i':181 ifindex = if_nametoindex(optarg);182 if (!ifindex)183 ifindex = atoi(optarg);184 break;185 case 'a':186 vip.family = parse_ipstr(optarg, vip.daddr.v6);187 if (vip.family == AF_UNSPEC)188 return 1;189 break;190 case 'p':191 if (parse_ports(optarg, &min_port, &max_port))192 return 1;193 break;194 case 'P':195 vip.protocol = atoi(optarg);196 break;197 case 's':198 case 'd':199 if (opt == 's')200 v6 = tnl.saddr.v6;201 else202 v6 = tnl.daddr.v6;203 204 family = parse_ipstr(optarg, v6);205 if (family == AF_UNSPEC)206 return 1;207 if (tnl.family == AF_UNSPEC) {208 tnl.family = family;209 } else if (tnl.family != family) {210 fprintf(stderr,211 "The IP version of the src and dst addresses used in the IP encapsulation does not match\n");212 return 1;213 }214 break;215 case 'm':216 if (!ether_aton_r(optarg,217 (struct ether_addr *)tnl.dmac)) {218 fprintf(stderr, "Invalid mac address:%s\n",219 optarg);220 return 1;221 }222 break;223 case 'T':224 kill_after_s = atoi(optarg);225 break;226 case 'S':227 xdp_flags |= XDP_FLAGS_SKB_MODE;228 break;229 case 'N':230 /* default, set below */231 break;232 case 'F':233 xdp_flags &= ~XDP_FLAGS_UPDATE_IF_NOEXIST;234 break;235 default:236 usage(argv[0]);237 return 1;238 }239 opt_flags[opt] = 0;240 }241 242 if (!(xdp_flags & XDP_FLAGS_SKB_MODE))243 xdp_flags |= XDP_FLAGS_DRV_MODE;244 245 for (i = 0; i < strlen(optstr); i++) {246 if (opt_flags[(unsigned int)optstr[i]]) {247 fprintf(stderr, "Missing argument -%c\n", optstr[i]);248 usage(argv[0]);249 return 1;250 }251 }252 253 if (!ifindex) {254 fprintf(stderr, "Invalid ifname\n");255 return 1;256 }257 258 snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);259 260 obj = bpf_object__open_file(filename, NULL);261 if (libbpf_get_error(obj))262 return 1;263 264 prog = bpf_object__next_program(obj, NULL);265 bpf_program__set_type(prog, BPF_PROG_TYPE_XDP);266 267 err = bpf_object__load(obj);268 if (err) {269 printf("bpf_object__load(): %s\n", strerror(errno));270 return 1;271 }272 prog_fd = bpf_program__fd(prog);273 274 rxcnt_map_fd = bpf_object__find_map_fd_by_name(obj, "rxcnt");275 vip2tnl_map_fd = bpf_object__find_map_fd_by_name(obj, "vip2tnl");276 if (vip2tnl_map_fd < 0 || rxcnt_map_fd < 0) {277 printf("bpf_object__find_map_fd_by_name failed\n");278 return 1;279 }280 281 signal(SIGINT, int_exit);282 signal(SIGTERM, int_exit);283 284 while (min_port <= max_port) {285 vip.dport = htons(min_port++);286 if (bpf_map_update_elem(vip2tnl_map_fd, &vip, &tnl,287 BPF_NOEXIST)) {288 perror("bpf_map_update_elem(&vip2tnl)");289 return 1;290 }291 }292 293 if (bpf_xdp_attach(ifindex, prog_fd, xdp_flags, NULL) < 0) {294 printf("link set xdp fd failed\n");295 return 1;296 }297 298 err = bpf_prog_get_info_by_fd(prog_fd, &info, &info_len);299 if (err) {300 printf("can't get prog info - %s\n", strerror(errno));301 return err;302 }303 prog_id = info.id;304 305 poll_stats(kill_after_s);306 307 bpf_xdp_detach(ifindex, xdp_flags, NULL);308 309 return 0;310}311