astraceroute.c

   1 /*
   2  * netsniff-ng - the packet sniffing beast
   3  * Copyright 2011 - 2013 Daniel Borkmann.
   4  * Subject to the GPL, version 2.
   5  */
   6
   7 #define _BSD_SOURCE
   8 #include <stdio.h>
   9 #include <stdlib.h>
  10 #include <signal.h>
  11 #include <getopt.h>
  12 #include <ctype.h>
  13 #include <stdint.h>
  14 #include <sys/types.h>
  15 #include <sys/stat.h>
  16 #include <sys/socket.h>
  17 #include <sys/fsuid.h>
  18 #include <fcntl.h>
  19 #include <time.h>
  20 #include <string.h>
  21 #include <asm/byteorder.h>
  22 #include <linux/tcp.h>
  23 #include <netinet/ip.h>
  24 #include <netinet/ip6.h>
  25 #include <netinet/in.h>
  26 #include <errno.h>
  27 #include <netdb.h>
  28 #include <sys/time.h>
  29 #include <arpa/inet.h>
  30 #include <linux/if_ether.h>
  31 #include <linux/icmp.h>
  32 #include <linux/icmpv6.h>
  33
  34 #include "bpf.h"
  35 #include "die.h"
  36 #include "dev.h"
  37 #include "sig.h"
  38 #include "config.h"
  39 #include "tprintf.h"
  40 #include "pkt_buff.h"
  41 #include "proto.h"
  42 #include "xmalloc.h"
  43 #include "ioops.h"
  44 #include "csum.h"
  45 #include "sock.h"
  46 #include "geoip.h"
  47 #include "ring.h"
  48 #include "built_in.h"
  49
  50 struct ctx {
  51         char *host, *port, *dev, *payload, *bind_addr;
  52         size_t totlen, rcvlen;
  53         int init_ttl, max_ttl, dns_resolv, queries, timeout;
  54         int syn, ack, ecn, fin, psh, rst, urg, tos, nofrag, proto, show;
  55         int sd_len, dport, latitude;
  56 };
  57
  58 struct proto_ops {
  59         int (*assembler)(uint8_t *packet, size_t len, int ttl, int proto,
  60                          const struct ctx *ctx, const struct sockaddr *dst,
  61                          const struct sockaddr *src);
  62         const struct sock_filter *filter;
  63         unsigned int flen;
  64         size_t min_len_tcp, min_len_icmp;
  65         int (*check)(uint8_t *packet, size_t len, int ttl, int id,
  66                      const struct sockaddr *src);
  67         void (*handler)(uint8_t *packet, size_t len, int dns_resolv,
  68                         int latitude);
  69 };
  70
  71 static sig_atomic_t sigint = 0;
  72
  73 static int assemble_ipv4(uint8_t *packet, size_t len, int ttl, int proto,
  74                          const struct ctx *ctx, const struct sockaddr *dst,
  75                          const struct sockaddr *src);
  76 static int assemble_ipv6(uint8_t *packet, size_t len, int ttl, int proto,
  77                          const struct ctx *ctx, const struct sockaddr *dst,
  78                          const struct sockaddr *src);
  79 static int check_ipv4(uint8_t *packet, size_t len, int ttl, int id,
  80                       const struct sockaddr *ss);
  81 static void handle_ipv4(uint8_t *packet, size_t len, int dns_resolv,
  82                         int latitude);
  83 static int check_ipv6(uint8_t *packet, size_t len, int ttl, int id,
  84                       const struct sockaddr *ss);
  85 static void handle_ipv6(uint8_t *packet, size_t len, int dns_resolv,
  86                         int latitude);
  87
  88 static const char *short_options = "H:p:nNf:m:b:i:d:q:x:SAEFPURt:Gl:hv46X:ZuL";
  89 static const struct option long_options[] = {
  90         {"host",        required_argument,      NULL, 'H'},
  91         {"port",        required_argument,      NULL, 'p'},
  92         {"init-ttl",    required_argument,      NULL, 'f'},
  93         {"max-ttl",     required_argument,      NULL, 'm'},
  94         {"bind",        required_argument,      NULL, 'b'},
  95         {"dev",         required_argument,      NULL, 'd'},
  96         {"num-probes",  required_argument,      NULL, 'q'},
  97         {"timeout",     required_argument,      NULL, 'x'},
  98         {"tos",         required_argument,      NULL, 't'},
  99         {"payload",     required_argument,      NULL, 'X'},
 100         {"totlen",      required_argument,      NULL, 'l'},
 101         {"numeric",     no_argument,            NULL, 'n'},
 102         {"latitude",    no_argument,            NULL, 'L'},
 103         {"update",      no_argument,            NULL, 'u'},
 104         {"dns",         no_argument,            NULL, 'N'},
 105         {"ipv4",        no_argument,            NULL, '4'},
 106         {"ipv6",        no_argument,            NULL, '6'},
 107         {"syn",         no_argument,            NULL, 'S'},
 108         {"ack",         no_argument,            NULL, 'A'},
 109         {"urg",         no_argument,            NULL, 'U'},
 110         {"fin",         no_argument,            NULL, 'F'},
 111         {"psh",         no_argument,            NULL, 'P'},
 112         {"rst",         no_argument,            NULL, 'R'},
 113         {"ecn-syn",     no_argument,            NULL, 'E'},
 114         {"show-packet", no_argument,            NULL, 'Z'},
 115         {"nofrag",      no_argument,            NULL, 'G'},
 116         {"version",     no_argument,            NULL, 'v'},
 117         {"help",        no_argument,            NULL, 'h'},
 118         {NULL, 0, NULL, 0}
 119 };
 120
 121 static const struct sock_filter ipv4_icmp_type_11[] = {
 122         { 0x28, 0, 0, 0x0000000c },     /* ldh [12]             */
 123         { 0x15, 0, 8, 0x00000800 },     /* jneq #0x800, drop    */
 124         { 0x30, 0, 0, 0x00000017 },     /* ldb [23]             */
 125         { 0x15, 0, 6, 0x00000001 },     /* jneq #0x1, drop      */
 126         { 0x28, 0, 0, 0x00000014 },     /* ldh [20]             */
 127         { 0x45, 4, 0, 0x00001fff },     /* jset #0x1fff, drop   */
 128         { 0xb1, 0, 0, 0x0000000e },     /* ldxb 4*([14]&0xf)    */
 129         { 0x50, 0, 0, 0x0000000e },     /* ldb [x + 14]         */
 130         { 0x15, 0, 1, 0x0000000b },     /* jneq #0xb, drop      */
 131         { 0x06, 0, 0, 0xffffffff },     /* ret #-1              */
 132         { 0x06, 0, 0, 0x00000000 },     /* drop: ret #0         */
 133 };
 134
 135 static const struct sock_filter ipv6_icmp6_type_3[] = {
 136         { 0x28, 0, 0, 0x0000000c },     /* ldh [12]             */
 137         { 0x15, 0, 5, 0x000086dd },     /* jneq #0x86dd, drop   */
 138         { 0x30, 0, 0, 0x00000014 },     /* ldb [20]             */
 139         { 0x15, 0, 3, 0x0000003a },     /* jneq #0x3a, drop     */
 140         { 0x30, 0, 0, 0x00000036 },     /* ldb [54]             */
 141         { 0x15, 0, 1, 0x00000003 },     /* jneq #0x3, drop      */
 142         { 0x06, 0, 0, 0xffffffff },     /* ret #-1              */
 143         { 0x06, 0, 0, 0x00000000 },     /* drop: ret #0         */
 144 };
 145
 146 static const struct proto_ops af_ops[] = {
 147         [IPPROTO_IP]    =       {
 148                         .assembler      =       assemble_ipv4,
 149                         .handler        =       handle_ipv4,
 150                         .check          =       check_ipv4,
 151                         .filter         =       ipv4_icmp_type_11,
 152                         .flen           =       array_size(ipv4_icmp_type_11),
 153                         .min_len_tcp    =       sizeof(struct iphdr) + sizeof(struct tcphdr),
 154                         .min_len_icmp   =       sizeof(struct iphdr) + sizeof(struct icmphdr),
 155                 },
 156         [IPPROTO_IPV6]  =       {
 157                         .assembler      =       assemble_ipv6,
 158                         .handler        =       handle_ipv6,
 159                         .check          =       check_ipv6,
 160                         .filter         =       ipv6_icmp6_type_3,
 161                         .flen           =       array_size(ipv6_icmp6_type_3),
 162                         .min_len_tcp    =       sizeof(struct ip6_hdr) + sizeof(struct tcphdr),
 163                         .min_len_icmp   =       sizeof(struct ip6_hdr) + sizeof(struct icmp6hdr),
 164                 },
 165 };
 166
 167 static void signal_handler(int number)
 168 {
 169         switch (number) {
 170         case SIGINT:
 171         case SIGQUIT:
 172         case SIGTERM:
 173                 sigint = 1;
 174         default:
 175                 break;
 176         }
 177 }
 178
 179 static void __noreturn help(void)
 180 {
 181         printf("\nastraceroute %s, autonomous system trace route utility\n", VERSION_STRING);
 182         puts("http://www.netsniff-ng.org\n\n"
 183              "Usage: astraceroute [options]\n"
 184              "Options:\n"
 185              " -H|--host <host>        Host/IPv4/IPv6 to lookup AS route to\n"
 186              " -p|--port <port>        Hosts port to lookup AS route to\n"
 187              " -i|-d|--dev <device>    Networking device, e.g. eth0\n"
 188              " -b|--bind <IP>          IP address to bind to, Must specify -6 for an IPv6 address\n"
 189              " -f|--init-ttl <ttl>     Set initial TTL\n"
 190              " -m|--max-ttl <ttl>      Set maximum TTL (def: 30)\n"
 191              " -q|--num-probes <num>   Number of max probes for each hop (def: 2)\n"
 192              " -x|--timeout <sec>      Probe response timeout in sec (def: 3)\n"
 193              " -X|--payload <string>   Specify a payload string to test DPIs\n"
 194              " -l|--totlen <len>       Specify total packet len\n"
 195              " -4|--ipv4               Use IPv4-only requests\n"
 196              " -6|--ipv6               Use IPv6-only requests\n"
 197              " -n|--numeric            Do not do reverse DNS lookup for hops\n"
 198              " -u|--update             Update GeoIP databases\n"
 199              " -L|--latitude           Show latitude and longitude\n"
 200              " -N|--dns                Do a reverse DNS lookup for hops\n"
 201              " -S|--syn                Set TCP SYN flag\n"
 202              " -A|--ack                Set TCP ACK flag\n"
 203              " -F|--fin                Set TCP FIN flag\n"
 204              " -P|--psh                Set TCP PSH flag\n"
 205              " -U|--urg                Set TCP URG flag\n"
 206              " -R|--rst                Set TCP RST flag\n"
 207              " -E|--ecn-syn            Send ECN SYN packets (RFC3168)\n"
 208              " -t|--tos <tos>          Set the IP TOS field\n"
 209              " -G|--nofrag             Set do not fragment bit\n"
 210              " -Z|--show-packet        Show returned packet on each hop\n"
 211              " -v|--version            Print version and exit\n"
 212              " -h|--help               Print this help and exit\n\n"
 213              "Examples:\n"
 214              "  IPv4 trace of AS with TCP SYN probe (this will most-likely pass):\n"
 215              "    astraceroute -i eth0 -N -S -H netsniff-ng.org\n"
 216              "  IPv4 trace of AS with TCP ECN SYN probe:\n"
 217              "    astraceroute -i eth0 -N -E -H netsniff-ng.org\n"
 218              "  IPv4 trace of AS with TCP FIN probe:\n"
 219              "    astraceroute -i eth0 -N -F -H netsniff-ng.org\n"
 220              "  IPv4 trace of AS with Xmas probe:\n"
 221              "    astraceroute -i eth0 -N -FPU -H netsniff-ng.org\n"
 222              "  IPv4 trace of AS with Null probe with ASCII payload:\n"
 223              "    astraceroute -i eth0 -N -H netsniff-ng.org -X \"censor-me\" -Z\n"
 224              "  IPv6 trace of AS up to www.6bone.net:\n"
 225              "    astraceroute -6 -i eth0 -S -E -N -H www.6bone.net\n\n"
 226              "Note:\n"
 227              "  If the TCP probe did not give any results, then astraceroute will\n"
 228              "  automatically probe for classic ICMP packets! To gather more\n"
 229              "  information about astraceroute's fetched AS numbers, see e.g.\n"
 230              "  http://bgp.he.net/AS<number>!\n\n"
 231              "Please report bugs to <bugs@netsniff-ng.org>\n"
 232              "Copyright (C) 2011-2013 Daniel Borkmann <dborkma@tik.ee.ethz.ch>\n"
 233              "Swiss federal institute of technology (ETH Zurich)\n"
 234              "License: GNU GPL version 2.0\n"
 235              "This is free software: you are free to change and redistribute it.\n"
 236              "There is NO WARRANTY, to the extent permitted by law.\n");
 237         die();
 238 }
 239
 240 static void __noreturn version(void)
 241 {
 242         printf("\nastraceroute %s, Git id: %s\n", VERSION_LONG, GITVERSION);
 243         puts("autonomous system trace route utility\n"
 244              "http://www.netsniff-ng.org\n\n"
 245              "Please report bugs to <bugs@netsniff-ng.org>\n"
 246              "Copyright (C) 2011-2013 Daniel Borkmann <dborkma@tik.ee.ethz.ch>\n"
 247              "Swiss federal institute of technology (ETH Zurich)\n"
 248              "License: GNU GPL version 2.0\n"
 249              "This is free software: you are free to change and redistribute it.\n"
 250              "There is NO WARRANTY, to the extent permitted by law.\n");
 251         die();
 252 }
 253
 254 static void __assemble_data(uint8_t *packet, size_t len, const char *payload)
 255 {
 256         size_t i;
 257
 258         if (payload == NULL) {
 259                 for (i = 0; i < len; ++i)
 260                         packet[i] = (uint8_t) rand();
 261         } else {
 262                 size_t lmin = min(len, strlen(payload));
 263
 264                 for (i = 0; i < lmin; ++i)
 265                         packet[i] = (uint8_t) payload[i];
 266                 for (i = lmin; i < len; ++i)
 267                         packet[i] = (uint8_t) rand();
 268         }
 269 }
 270
 271 static void __assemble_icmp4(uint8_t *packet, size_t len)
 272 {
 273         struct icmphdr *icmph = (struct icmphdr *) packet;
 274
 275         bug_on(len < sizeof(struct icmphdr));
 276
 277         icmph->type = ICMP_ECHO;
 278         icmph->code = 0;
 279         icmph->checksum = 0;
 280 }
 281
 282 static void __assemble_icmp6(uint8_t *packet, size_t len)
 283 {
 284         struct icmp6hdr *icmp6h = (struct icmp6hdr *) packet;
 285
 286         bug_on(len < sizeof(struct icmp6hdr));
 287
 288         icmp6h->icmp6_type = ICMPV6_ECHO_REQUEST;
 289         icmp6h->icmp6_code = 0;
 290         icmp6h->icmp6_cksum = 0;
 291 }
 292
 293 static void __assemble_tcp(uint8_t *packet, size_t len, int syn, int ack,
 294                            int urg, int fin, int rst, int psh, int ecn,
 295                            int dport)
 296 {
 297         struct tcphdr *tcph = (struct tcphdr *) packet;
 298
 299         bug_on(len < sizeof(struct tcphdr));
 300
 301         tcph->source = htons((uint16_t) rand());
 302         tcph->dest = htons((uint16_t) dport);
 303
 304         tcph->seq = htonl(rand());
 305         tcph->ack_seq = (!!ack ? htonl(rand()) : 0);
 306
 307         tcph->doff = 5;
 308
 309         tcph->syn = !!syn;
 310         tcph->ack = !!ack;
 311         tcph->urg = !!urg;
 312         tcph->fin = !!fin;
 313         tcph->rst = !!rst;
 314         tcph->psh = !!psh;
 315         tcph->ece = !!ecn;
 316         tcph->cwr = !!ecn;
 317
 318         tcph->window = htons((uint16_t) (100 + (rand() % 65435)));
 319         tcph->urg_ptr = (!!urg ? htons((uint16_t) rand()) :  0);
 320         tcph->check = 0;
 321 }
 322
 323 static int assemble_ipv4(uint8_t *packet, size_t len, int ttl, int proto,
 324                          const struct ctx *ctx, const struct sockaddr *dst,
 325                          const struct sockaddr *src)
 326 {
 327         uint8_t *data;
 328         size_t data_len, off_next = 0;
 329         struct iphdr *iph = (struct iphdr *) packet;
 330
 331         bug_on(!src || !dst);
 332         bug_on(src->sa_family != PF_INET || dst->sa_family != PF_INET);
 333         bug_on(len < sizeof(*iph) + min(sizeof(struct tcphdr),
 334                                         sizeof(struct icmphdr)));
 335
 336         iph->ihl = 5;
 337         iph->version = 4;
 338         iph->tos = (uint8_t) ctx->tos;
 339
 340         iph->tot_len = htons((uint16_t) len);
 341         iph->id = htons((uint16_t) rand());
 342
 343         iph->frag_off = ctx->nofrag ? IP_DF : 0;
 344         iph->ttl = (uint8_t) ttl;
 345
 346         iph->saddr = ((const struct sockaddr_in *) src)->sin_addr.s_addr;
 347         iph->daddr = ((const struct sockaddr_in *) dst)->sin_addr.s_addr;
 348
 349         iph->protocol = (uint8_t) proto;
 350
 351         data = packet + sizeof(*iph);
 352         data_len = len - sizeof(*iph);
 353
 354         switch (proto) {
 355         case IPPROTO_TCP:
 356                 __assemble_tcp(data, data_len, ctx->syn, ctx->ack, ctx->urg,
 357                                ctx->fin, ctx->rst, ctx->psh, ctx->ecn, ctx->dport);
 358                 off_next = sizeof(struct tcphdr);
 359                 break;
 360         case IPPROTO_ICMP:
 361                 __assemble_icmp4(data, data_len);
 362                 off_next = sizeof(struct icmphdr);
 363                 break;
 364         default:
 365                 bug();
 366         }
 367
 368         data = packet + sizeof(*iph) + off_next;
 369         data_len = len - sizeof(*iph) - off_next;
 370
 371         __assemble_data(data, data_len, ctx->payload);
 372
 373         iph->check = csum((unsigned short *) packet, ntohs(iph->tot_len) >> 1);
 374
 375         return ntohs(iph->id);
 376 }
 377
 378 static int assemble_ipv6(uint8_t *packet, size_t len, int ttl, int proto,
 379                          const struct ctx *ctx, const struct sockaddr *dst,
 380                          const struct sockaddr *src)
 381 {
 382         uint8_t *data;
 383         size_t data_len, off_next = 0;
 384         struct ip6_hdr *ip6h = (struct ip6_hdr *) packet;
 385
 386         bug_on(!src || !dst);
 387         bug_on(src->sa_family != PF_INET6 || dst->sa_family != PF_INET6);
 388         bug_on(len < sizeof(*ip6h) + min(sizeof(struct tcphdr),
 389                                          sizeof(struct icmp6hdr)));
 390
 391         ip6h->ip6_flow = htonl(rand() & 0x000fffff);
 392         ip6h->ip6_vfc = 0x60;
 393
 394         ip6h->ip6_plen = htons((uint16_t) len - sizeof(*ip6h));
 395         ip6h->ip6_nxt = (uint8_t) proto;
 396         ip6h->ip6_hlim = (uint8_t) ttl;
 397
 398         memcpy(&ip6h->ip6_src, &(((const struct sockaddr_in6 *)
 399                src)->sin6_addr), sizeof(ip6h->ip6_src));
 400         memcpy(&ip6h->ip6_dst, &(((const struct sockaddr_in6 *)
 401                dst)->sin6_addr), sizeof(ip6h->ip6_dst));
 402
 403         data = packet + sizeof(*ip6h);
 404         data_len = len - sizeof(*ip6h);
 405
 406         switch (proto) {
 407         case IPPROTO_TCP:
 408                 __assemble_tcp(data, data_len, ctx->syn, ctx->ack, ctx->urg,
 409                                ctx->fin, ctx->rst, ctx->psh, ctx->ecn, ctx->dport);
 410                 off_next = sizeof(struct tcphdr);
 411                 break;
 412         case IPPROTO_ICMP:
 413         case IPPROTO_ICMPV6:
 414                 __assemble_icmp6(data, data_len);
 415                 off_next = sizeof(struct icmp6hdr);
 416                 break;
 417         default:
 418                 bug();
 419         }
 420
 421         data = packet + sizeof(*ip6h) + off_next;
 422         data_len = len - sizeof(*ip6h) - off_next;
 423
 424         __assemble_data(data, data_len, ctx->payload);
 425
 426         return ntohl(ip6h->ip6_flow) & 0x000fffff;
 427 }
 428
 429 static int check_ipv4(uint8_t *packet, size_t len, int ttl __maybe_unused,
 430                       int id, const struct sockaddr *ss)
 431 {
 432         struct iphdr *iph = (struct iphdr *) packet;
 433         struct iphdr *iph_inner;
 434         struct icmphdr *icmph;
 435
 436         if (iph->protocol != IPPROTO_ICMP)
 437                 return -EINVAL;
 438         if (iph->daddr != ((const struct sockaddr_in *) ss)->sin_addr.s_addr)
 439                 return -EINVAL;
 440
 441         icmph = (struct icmphdr *) (packet + sizeof(struct iphdr));
 442         if (icmph->type != ICMP_TIME_EXCEEDED)
 443                 return -EINVAL;
 444         if (icmph->code != ICMP_EXC_TTL)
 445                 return -EINVAL;
 446
 447         iph_inner = (struct iphdr *) (packet + sizeof(struct iphdr) +
 448                                       sizeof(struct icmphdr));
 449         if (ntohs(iph_inner->id) != id)
 450                 return -EINVAL;
 451
 452         return len;
 453 }
 454
 455 static void handle_ipv4(uint8_t *packet, size_t len __maybe_unused,
 456                         int dns_resolv, int latitude)
 457 {
 458         char hbuff[NI_MAXHOST];
 459         struct iphdr *iph = (struct iphdr *) packet;
 460         struct sockaddr_in sd;
 461         struct hostent *hent;
 462         const char *as, *country, *city;
 463
 464         memset(hbuff, 0, sizeof(hbuff));
 465         memset(&sd, 0, sizeof(sd));
 466         sd.sin_family = PF_INET;
 467         sd.sin_addr.s_addr = iph->saddr;
 468
 469         getnameinfo((struct sockaddr *) &sd, sizeof(sd),
 470                     hbuff, sizeof(hbuff), NULL, 0, NI_NUMERICHOST);
 471
 472         as = geoip4_as_name(&sd);
 473         country = geoip4_country_name(&sd);
 474         city = geoip4_city_name(&sd);
 475
 476         if (dns_resolv) {
 477                 hent = gethostbyaddr(&sd.sin_addr, sizeof(sd.sin_addr), PF_INET);
 478                 if (hent)
 479                         printf(" %s (%s)", hent->h_name, hbuff);
 480                 else
 481                         printf(" %s", hbuff);
 482         } else {
 483                 printf(" %s", hbuff);
 484         }
 485         if (as)
 486                 printf(" in %s", as);
 487         if (country) {
 488                 printf(" in %s", country);
 489                 if (city)
 490                         printf(", %s", city);
 491         }
 492         if (latitude)
 493                 printf(" (%f/%f)", geoip4_latitude(&sd), geoip4_longitude(&sd));
 494 }
 495
 496 static int check_ipv6(uint8_t *packet, size_t len, int ttl __maybe_unused,
 497                       int id, const struct sockaddr *ss)
 498 {
 499         struct ip6_hdr *ip6h = (struct ip6_hdr *) packet;
 500         struct ip6_hdr *ip6h_inner;
 501         struct icmp6hdr *icmp6h;
 502
 503         if (ip6h->ip6_nxt != 0x3a)
 504                 return -EINVAL;
 505         if (memcmp(&ip6h->ip6_dst, &(((const struct sockaddr_in6 *)
 506                    ss)->sin6_addr), sizeof(ip6h->ip6_dst)))
 507                 return -EINVAL;
 508
 509         icmp6h = (struct icmp6hdr *) (packet + sizeof(*ip6h));
 510         if (icmp6h->icmp6_type != ICMPV6_TIME_EXCEED)
 511                 return -EINVAL;
 512         if (icmp6h->icmp6_code != ICMPV6_EXC_HOPLIMIT)
 513                 return -EINVAL;
 514
 515         ip6h_inner = (struct ip6_hdr *) (packet + sizeof(*ip6h) + sizeof(*icmp6h));
 516         if ((ntohl(ip6h_inner->ip6_flow) & 0x000fffff) != (uint32_t) id)
 517                 return -EINVAL;
 518
 519         return len;
 520 }
 521
 522 static void handle_ipv6(uint8_t *packet, size_t len __maybe_unused,
 523                         int dns_resolv, int latitude)
 524 {
 525         char hbuff[NI_MAXHOST];
 526         struct ip6_hdr *ip6h = (struct ip6_hdr *) packet;
 527         struct sockaddr_in6 sd;
 528         struct hostent *hent;
 529         const char *as, *country, *city;
 530
 531         memset(hbuff, 0, sizeof(hbuff));
 532         memset(&sd, 0, sizeof(sd));
 533         sd.sin6_family = PF_INET6;
 534         memcpy(&sd.sin6_addr, &ip6h->ip6_src, sizeof(ip6h->ip6_src));
 535
 536         getnameinfo((struct sockaddr *) &sd, sizeof(sd),
 537                     hbuff, sizeof(hbuff), NULL, 0, NI_NUMERICHOST);
 538
 539         as = geoip6_as_name(&sd);
 540         country = geoip6_country_name(&sd);
 541         city = geoip6_city_name(&sd);
 542
 543         if (dns_resolv) {
 544                 hent = gethostbyaddr(&sd.sin6_addr, sizeof(sd.sin6_addr), PF_INET6);
 545                 if (hent)
 546                         printf(" %s (%s)", hent->h_name, hbuff);
 547                 else
 548                         printf(" %s", hbuff);
 549         } else {
 550                 printf(" %s", hbuff);
 551         }
 552         if (as)
 553                 printf(" in %s", as);
 554         if (country) {
 555                 printf(" in %s", country);
 556                 if (city)
 557                         printf(", %s", city);
 558         }
 559         if (latitude)
 560                 printf(" (%f/%f)", geoip6_latitude(&sd), geoip6_longitude(&sd));
 561 }
 562
 563 static void show_trace_info(struct ctx *ctx, const struct sockaddr_storage *ss,
 564                             const struct sockaddr_storage *sd)
 565 {
 566         char hbuffs[256], hbuffd[256];
 567
 568         memset(hbuffd, 0, sizeof(hbuffd));
 569         getnameinfo((struct sockaddr *) sd, sizeof(*sd),
 570                     hbuffd, sizeof(hbuffd), NULL, 0, NI_NUMERICHOST);
 571
 572         memset(hbuffs, 0, sizeof(hbuffs));
 573         getnameinfo((struct sockaddr *) ss, sizeof(*ss),
 574                     hbuffs, sizeof(hbuffs), NULL, 0, NI_NUMERICHOST);
 575
 576         printf("AS path IPv%d TCP trace from %s to %s:%s (%s) with len %zu "
 577                "Bytes, %u max hops\n", ctx->proto == IPPROTO_IP ? 4 : 6,
 578                hbuffs, hbuffd, ctx->port, ctx->host, ctx->totlen, ctx->max_ttl);
 579
 580         printf("Using flags SYN:%d,ACK:%d,ECN:%d,FIN:%d,PSH:%d,RST:%d,URG:%d\n",
 581                ctx->syn, ctx->ack, ctx->ecn, ctx->fin, ctx->psh, ctx->rst, ctx->urg);
 582
 583         if (ctx->payload)
 584                 printf("With payload: \'%s\'\n", ctx->payload);
 585 }
 586
 587 static int get_remote_fd(struct ctx *ctx, struct sockaddr_storage *ss,
 588                          struct sockaddr_storage *sd)
 589 {
 590         int fd = -1, ret, one = 1, af = AF_INET;
 591         struct addrinfo hints, *ahead, *ai;
 592         unsigned char bind_ip[sizeof(struct in6_addr)];
 593
 594         memset(&hints, 0, sizeof(hints));
 595         hints.ai_family = PF_UNSPEC;
 596         hints.ai_socktype = SOCK_STREAM;
 597         hints.ai_protocol = IPPROTO_TCP;
 598         hints.ai_flags = AI_NUMERICSERV;
 599
 600         ret = getaddrinfo(ctx->host, ctx->port, &hints, &ahead);
 601         if (ret < 0)
 602                 panic("Cannot get address info!\n");
 603
 604         for (ai = ahead; ai != NULL && fd < 0; ai = ai->ai_next) {
 605                 if (!((ai->ai_family == PF_INET6 && ctx->proto == IPPROTO_IPV6) ||
 606                       (ai->ai_family == PF_INET  && ctx->proto == IPPROTO_IP)))
 607                         continue;
 608
 609                 fd = socket(ai->ai_family, SOCK_RAW, IPPROTO_RAW);
 610                 if (fd < 0)
 611                         continue;
 612
 613                 memset(ss, 0, sizeof(*ss));
 614                 ret = device_address(ctx->dev, ai->ai_family, ss);
 615                 if (ret < 0 && !ctx->bind_addr)
 616                         panic("Cannot get own device address!\n");
 617
 618                 if (ctx->bind_addr) {
 619                         if (ctx->proto == IPPROTO_IPV6)
 620                                 af = AF_INET6;
 621
 622                         if (inet_pton(af, ctx->bind_addr, &bind_ip) != 1)
 623                                 panic("Address is invalid!\n");
 624
 625                         if (af == AF_INET6) {
 626                                 struct sockaddr_in6 *ss6 = (struct sockaddr_in6 *) ss;
 627                                 memcpy(&ss6->sin6_addr.s6_addr, &bind_ip, sizeof(struct in6_addr));
 628                         } else {
 629                                 struct sockaddr_in *ss4 = (struct sockaddr_in *) ss;
 630                                 memcpy(&ss4->sin_addr.s_addr, &bind_ip, sizeof(struct in_addr));
 631                         }
 632                 }
 633
 634                 ret = bind(fd, (struct sockaddr *) ss, sizeof(*ss));
 635                 if (ret < 0)
 636                         panic("Cannot bind socket!\n");
 637
 638                 memset(sd, 0, sizeof(*sd));
 639                 memcpy(sd, ai->ai_addr, ai->ai_addrlen);
 640
 641                 ctx->sd_len = ai->ai_addrlen;
 642                 ctx->dport = strtoul(ctx->port, NULL, 10);
 643
 644                 ret = setsockopt(fd, ctx->proto, IP_HDRINCL, &one, sizeof(one));
 645                 if (ret < 0)
 646                         panic("Kernel does not support IP_HDRINCL!\n");
 647
 648                 if (ai->ai_family == PF_INET6) {
 649                         struct sockaddr_in6 *sd6 = (struct sockaddr_in6 *) sd;
 650
 651                         sd6->sin6_port = 0;
 652                 }
 653
 654                 break;
 655         }
 656
 657         freeaddrinfo(ahead);
 658
 659         if (fd < 0)
 660                 panic("Cannot create socket! Does remote "
 661                       "support IPv%d?!\n",
 662                       ctx->proto == IPPROTO_IP ? 4 : 6);
 663
 664         return fd;
 665 }
 666
 667 static void inject_filter(struct ctx *ctx, int fd)
 668 {
 669         struct sock_fprog bpf_ops;
 670
 671         enable_kernel_bpf_jit_compiler();
 672
 673         memset(&bpf_ops, 0, sizeof(bpf_ops));
 674         bpf_ops.filter = (struct sock_filter *) af_ops[ctx->proto].filter;
 675         bpf_ops.len = af_ops[ctx->proto].flen;
 676
 677         bpf_attach_to_sock(fd, &bpf_ops);
 678 }
 679
 680 static int __process_node(struct ctx *ctx, int fd, int fd_cap, int ttl,
 681                           int inner_proto, uint8_t *pkt_snd, uint8_t *pkt_rcv,
 682                           const struct sockaddr_storage *ss,
 683                           const struct sockaddr_storage *sd, struct timeval *diff)
 684 {
 685         int pkt_id, ret, timeout;
 686         struct pollfd pfd;
 687         struct timeval start, end;
 688
 689         prepare_polling(fd_cap, &pfd);
 690
 691         memset(pkt_snd, 0, ctx->totlen);
 692         pkt_id = af_ops[ctx->proto].assembler(pkt_snd, ctx->totlen, ttl,
 693                                               inner_proto, ctx,
 694                                               (const struct sockaddr *) sd,
 695                                               (const struct sockaddr *) ss);
 696
 697         ret = sendto(fd, pkt_snd, ctx->totlen, 0, (struct sockaddr *) sd,
 698                      ctx->sd_len);
 699         if (ret < 0)
 700                 panic("sendto failed: %s\n", strerror(errno));
 701
 702         bug_on(gettimeofday(&start, NULL));
 703
 704         timeout = (ctx->timeout > 0 ? ctx->timeout : 2) * 1000;
 705
 706         ret = poll(&pfd, 1, timeout);
 707         if (ret > 0 && pfd.revents & POLLIN && sigint == 0) {
 708                 bug_on(gettimeofday(&end, NULL));
 709                 if (diff)
 710                         timersub(&end, &start, diff);
 711
 712                 ret = recvfrom(fd_cap, pkt_rcv, ctx->rcvlen, 0, NULL, NULL);
 713                 if (ret < (int) (sizeof(struct ethhdr) + af_ops[ctx->proto].min_len_icmp))
 714                         return -EIO;
 715
 716                 return af_ops[ctx->proto].check(pkt_rcv + sizeof(struct ethhdr),
 717                                                 ret - sizeof(struct ethhdr), ttl,
 718                                                 pkt_id, (const struct sockaddr *) ss);
 719         } else {
 720                 return -EIO;
 721         }
 722
 723         return 0;
 724 }
 725
 726 static void timerdiv(const unsigned long divisor, const struct timeval *tv,
 727                      struct timeval *result)
 728 {
 729         uint64_t x = ((uint64_t) tv->tv_sec * 1000 * 1000 + tv->tv_usec) / divisor;
 730
 731         result->tv_sec = x / 1000 / 1000;
 732         result->tv_usec = x % (1000 * 1000);
 733 }
 734
 735 static int timevalcmp(const void *t1, const void *t2)
 736 {
 737         if (timercmp((struct timeval *) t1, (struct timeval *) t2, <))
 738                 return -1;
 739         if (timercmp((struct timeval *) t1, (struct timeval *) t2, >))
 740                 return  1;
 741
 742         return 0;
 743 }
 744
 745 static int __process_time(struct ctx *ctx, int fd, int fd_cap, int ttl,
 746                           int inner_proto, uint8_t *pkt_snd, uint8_t *pkt_rcv,
 747                           const struct sockaddr_storage *ss,
 748                           const struct sockaddr_storage *sd)
 749 {
 750         size_t i, j = 0;
 751         int good = 0, ret = -EIO, idx, ret_good = -EIO;
 752         struct timeval probes[9], *tmp, sum, res;
 753         uint8_t *trash = xmalloc(ctx->rcvlen);
 754         char *cwait[] = { "-", "\\", "|", "/" };
 755         const char *proto_short[] = {
 756                 [IPPROTO_TCP]           =       "t",
 757                 [IPPROTO_ICMP]          =       "i",
 758                 [IPPROTO_ICMPV6]        =       "i",
 759         };
 760
 761         memset(probes, 0, sizeof(probes));
 762         for (i = 0; i < array_size(probes) && sigint == 0; ++i) {
 763                 ret = __process_node(ctx, fd, fd_cap, ttl, inner_proto,
 764                                      pkt_snd, good == 0 ? pkt_rcv : trash,
 765                                      ss, sd, &probes[i]);
 766                 if (ret > 0) {
 767                         if (good == 0)
 768                                 ret_good = ret;
 769                         good++;
 770                 }
 771
 772                 if (good == 0 && ctx->queries == (int) i)
 773                         break;
 774
 775                 usleep(50000);
 776
 777                 printf("\r%2d: %s", ttl, cwait[j++]);
 778                 fflush(stdout);
 779                 if (j >= array_size(cwait))
 780                         j = 0;
 781         }
 782
 783         if (good == 0) {
 784                 xfree(trash);
 785                 return -EIO;
 786         }
 787
 788         tmp = xmalloc(sizeof(struct timeval) * good);
 789         for (i = j = 0; i < array_size(probes); ++i) {
 790                 if (probes[i].tv_sec == 0 && probes[i].tv_usec == 0)
 791                         continue;
 792                 tmp[j].tv_sec = probes[i].tv_sec;
 793                 tmp[j].tv_usec = probes[i].tv_usec;
 794                 j++;
 795         }
 796
 797         qsort(tmp, j, sizeof(struct timeval), timevalcmp);
 798
 799         printf("\r%2d: %s[", ttl, proto_short[inner_proto]);
 800         idx = j / 2;
 801         switch (j % 2) {
 802         case 0:
 803                 timeradd(&tmp[idx], &tmp[idx - 1], &sum);
 804                 timerdiv(2, &sum, &res);
 805                 if (res.tv_sec > 0)
 806                         printf("%lu sec ", res.tv_sec);
 807                 printf("%7lu us", res.tv_usec);
 808                 break;
 809         case 1:
 810                 if (tmp[idx].tv_sec > 0)
 811                         printf("%lu sec ", tmp[idx].tv_sec);
 812                 printf("%7lu us", tmp[idx].tv_usec);
 813                 break;
 814         }
 815         printf("]");
 816
 817         xfree(tmp);
 818         xfree(trash);
 819
 820         return ret_good;
 821 }
 822
 823 static int __probe_remote(struct ctx *ctx, int fd, int fd_cap, int ttl,
 824                           uint8_t *pkt_snd, uint8_t *pkt_rcv,
 825                           const struct sockaddr_storage *ss,
 826                           const struct sockaddr_storage *sd,
 827                           int inner_proto)
 828 {
 829         int ret = -EIO, tries = ctx->queries;
 830
 831         while (tries-- > 0 && sigint == 0) {
 832                 ret = __process_time(ctx, fd, fd_cap, ttl, inner_proto,
 833                                      pkt_snd, pkt_rcv, ss, sd);
 834                 if (ret < 0)
 835                         continue;
 836
 837                 af_ops[ctx->proto].handler(pkt_rcv + sizeof(struct ethhdr),
 838                                            ret - sizeof(struct ethhdr),
 839                                            ctx->dns_resolv, ctx->latitude);
 840                 if (ctx->show) {
 841                         struct pkt_buff *pkt;
 842
 843                         printf("\n");
 844                         pkt = pkt_alloc(pkt_rcv, ret);
 845                         hex_ascii(pkt);
 846                         tprintf_flush();
 847                         pkt_free(pkt);
 848                 }
 849
 850                 break;
 851         }
 852
 853         return ret;
 854 }
 855
 856 static int __process_ttl(struct ctx *ctx, int fd, int fd_cap, int ttl,
 857                          uint8_t *pkt_snd, uint8_t *pkt_rcv,
 858                          const struct sockaddr_storage *ss,
 859                          const struct sockaddr_storage *sd)
 860 {
 861         int ret = -EIO;
 862         size_t i;
 863         const int inner_protos[] = {
 864                 IPPROTO_TCP,
 865                 IPPROTO_ICMP,
 866         };
 867
 868         printf("%2d: ", ttl);
 869         fflush(stdout);
 870
 871         for (i = 0; i < array_size(inner_protos) && sigint == 0; ++i) {
 872                 ret = __probe_remote(ctx, fd, fd_cap, ttl, pkt_snd, pkt_rcv, ss, sd,
 873                                      inner_protos[i]);
 874                 if (ret > 0)
 875                         break;
 876         }
 877
 878         if (ret <= 0)
 879                 printf("\r%2d: ?[ no answer]", ttl);
 880         if (ctx->show == 0)
 881                 printf("\n");
 882         if (ctx->show && ret <= 0)
 883                 printf("\n\n");
 884
 885         fflush(stdout);
 886         return 0;
 887 }
 888
 889 static int main_trace(struct ctx *ctx)
 890 {
 891         int fd, fd_cap, ifindex, ttl;
 892         struct ring dummy_ring;
 893         struct sockaddr_storage ss, sd;
 894         uint8_t *pkt_snd, *pkt_rcv;
 895
 896         fd = get_remote_fd(ctx, &ss, &sd);
 897         fd_cap = pf_socket();
 898
 899         inject_filter(ctx, fd_cap);
 900
 901         ifindex = device_ifindex(ctx->dev);
 902         bind_ring_generic(fd_cap, &dummy_ring, ifindex, false);
 903
 904         if (ctx->totlen < af_ops[ctx->proto].min_len_tcp) {
 905                 ctx->totlen = af_ops[ctx->proto].min_len_tcp;
 906                 if (ctx->payload)
 907                         ctx->totlen += strlen(ctx->payload);
 908         }
 909
 910         ctx->rcvlen = device_mtu(ctx->dev) - sizeof(struct ethhdr);
 911         if (ctx->totlen >= ctx->rcvlen)
 912                 panic("Packet len exceeds device MTU!\n");
 913
 914         pkt_snd = xmalloc(ctx->totlen);
 915         pkt_rcv = xmalloc(ctx->rcvlen);
 916
 917         show_trace_info(ctx, &ss, &sd);
 918
 919         for (ttl = ctx->init_ttl; ttl <= ctx->max_ttl && sigint == 0; ++ttl)
 920                 __process_ttl(ctx, fd, fd_cap, ttl, pkt_snd, pkt_rcv,
 921                               &ss, &sd);
 922
 923         xfree(pkt_snd);
 924         xfree(pkt_rcv);
 925
 926         close(fd_cap);
 927         close(fd);
 928
 929         return 0;
 930 }
 931
 932 int main(int argc, char **argv)
 933 {
 934         int c, opt_index, ret;
 935         struct ctx ctx;
 936
 937         setfsuid(getuid());
 938         setfsgid(getgid());
 939
 940         srand(time(NULL));
 941
 942         memset(&ctx, 0, sizeof(ctx));
 943         ctx.init_ttl = 1;
 944         ctx.max_ttl = 30;
 945         ctx.queries = 2;
 946         ctx.timeout = 2;
 947         ctx.proto = IPPROTO_IP;
 948         ctx.payload = NULL;
 949         ctx.dev = xstrdup("eth0");
 950         ctx.port = xstrdup("80");
 951         ctx.bind_addr = NULL;
 952
 953         while ((c = getopt_long(argc, argv, short_options, long_options,
 954                 &opt_index)) != EOF) {
 955                 switch (c) {
 956                 case 'h':
 957                         help();
 958                         break;
 959                 case 'v':
 960                         version();
 961                         break;
 962                 case 'u':
 963                         update_geoip();
 964                         die();
 965                         break;
 966                 case 'H':
 967                         ctx.host = xstrdup(optarg);
 968                         break;
 969                 case 'p':
 970                         if (ctx.port)
 971                                 xfree(ctx.port);
 972                         ctx.port = xstrdup(optarg);
 973                         break;
 974                 case 'n':
 975                         ctx.dns_resolv = 0;
 976                         break;
 977                 case '4':
 978                         ctx.proto = IPPROTO_IP;
 979                         break;
 980                 case '6':
 981                         ctx.proto = IPPROTO_IPV6;
 982                         break;
 983                 case 'Z':
 984                         ctx.show = 1;
 985                         break;
 986                 case 'N':
 987                         ctx.dns_resolv = 1;
 988                         break;
 989                 case 'f':
 990                         ctx.init_ttl = atoi(optarg);
 991                         if (ctx.init_ttl <= 0)
 992                                 help();
 993                         break;
 994                 case 'm':
 995                         ctx.max_ttl = atoi(optarg);
 996                         if (ctx.max_ttl <= 0)
 997                                 help();
 998                         break;
 999                 case 'b':
1000                         ctx.bind_addr = xstrdup(optarg);
1001                         break;
1002                 case 'i':
1003                 case 'd':
1004                         free(ctx.dev);
1005                         ctx.dev = xstrdup(optarg);
1006                         break;
1007                 case 'q':
1008                         ctx.queries = atoi(optarg);
1009                         if (ctx.queries <= 0)
1010                                 help();
1011                         break;
1012                 case 'x':
1013                         ctx.timeout = atoi(optarg);
1014                         if (ctx.timeout <= 0)
1015                                 help();
1016                         break;
1017                 case 'L':
1018                         ctx.latitude = 1;
1019                         break;
1020                 case 'S':
1021                         ctx.syn = 1;
1022                         break;
1023                 case 'A':
1024                         ctx.ack = 1;
1025                         break;
1026                 case 'F':
1027                         ctx.fin = 1;
1028                         break;
1029                 case 'U':
1030                         ctx.urg = 1;
1031                         break;
1032                 case 'P':
1033                         ctx.psh = 1;
1034                         break;
1035                 case 'R':
1036                         ctx.rst = 1;
1037                         break;
1038                 case 'E':
1039                         ctx.syn = 1;
1040                         ctx.ecn = 1;
1041                         break;
1042                 case 't':
1043                         ctx.tos = atoi(optarg);
1044                         if (ctx.tos < 0)
1045                                 help();
1046                         break;
1047                 case 'G':
1048                         ctx.nofrag = 1;
1049                         break;
1050                 case 'X':
1051                         ctx.payload = xstrdup(optarg);
1052                         break;
1053                 case 'l':
1054                         ctx.totlen = strtoul(optarg, NULL, 10);
1055                         if (ctx.totlen == 0)
1056                                 help();
1057                         break;
1058                 case '?':
1059                         switch (optopt) {
1060                         case 'H':
1061                         case 'p':
1062                         case 'f':
1063                         case 'm':
1064                         case 'i':
1065                         case 'd':
1066                         case 'q':
1067                         case 'x':
1068                         case 'X':
1069                         case 't':
1070                         case 'l':
1071                                 panic("Option -%c requires an argument!\n",
1072                                       optopt);
1073                         default:
1074                                 if (isprint(optopt))
1075                                         printf("Unknown option character `0x%X\'!\n", optopt);
1076                                 die();
1077                 }
1078                 default:
1079                         break;
1080                 }
1081         }
1082
1083         if (argc < 3 || !ctx.host || !ctx.port || ctx.init_ttl > ctx.max_ttl ||
1084             ctx.init_ttl > MAXTTL || ctx.max_ttl > MAXTTL)
1085                 help();
1086
1087         if (!device_up_and_running(ctx.dev))
1088                 panic("Networking device not up and running!\n");
1089         if (device_mtu(ctx.dev) <= ctx.totlen)
1090                 panic("Packet larger than device MTU!\n");
1091
1092         register_signal(SIGHUP, signal_handler);
1093         register_signal(SIGINT, signal_handler);
1094         register_signal(SIGQUIT, signal_handler);
1095         register_signal(SIGTERM, signal_handler);
1096
1097         tprintf_init();
1098         init_geoip(1);
1099
1100         ret = main_trace(&ctx);
1101
1102         destroy_geoip();
1103         tprintf_cleanup();
1104
1105         free(ctx.dev);
1106         free(ctx.host);
1107         free(ctx.port);
1108         free(ctx.bind_addr);
1109         free(ctx.payload);
1110
1111         return ret;
1112 }