File: dump_router6.c

package info (click to toggle)
thc-ipv6 3.6-1
  • links: PTS, VCS
  • area: main
  • in suites: bullseye, buster, sid
  • size: 2,116 kB
  • sloc: ansic: 52,618; sh: 529; makefile: 77; perl: 34
file content (263 lines) | stat: -rw-r--r-- 7,608 bytes parent folder | download
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/time.h>
#include <sys/resource.h>
#include <sys/wait.h>
#include <time.h>
#include <pcap.h>
#include "thc-ipv6.h"

#define MAX_SEEN 255

char *frbuf, *frbuf2, *frint, buf3[1504];
int frbuflen, frbuf2len, do_hop = 0, do_frag = 0, do_dst = 0, type = NXT_ICMP6, seen_cnt = 0;
unsigned char *frip6, *frmac, *frdst;
thc_ipv6_hdr *frhdr = NULL;
char seen[MAX_SEEN + 1][16];
extern int do_hdr_size;

void help(char *prg) {
  printf("%s %s (c) 2019 by %s %s\n\n", prg, VERSION, AUTHOR, RESOURCE);
  printf("Syntax: %s interface [target]\n\n", prg);
  printf("Dumps all local routers and their information\n\n");
//  printf("Use -r to use raw mode.\n\n");
  exit(-1);
}

void dump_ra_reply(u_char *foo, const struct pcap_pkthdr *header, const unsigned char *data) {
  unsigned char *ipv6hdr = (unsigned char *) (data + 14), *ptr, *ptr2, tmpbuf[16];
  int i, k, len = header->caplen - 14;

  if (do_hdr_size > 0) {
    ipv6hdr = (unsigned char *) (data + do_hdr_size);
    len -= (do_hdr_size - 14);
    if ((ipv6hdr[0] & 240) != 0x60)
      return;
  }

  if (ipv6hdr[6] != NXT_ICMP6 || ipv6hdr[40] != ICMP6_ROUTERADV || len < 40 + 16)
    return;

  if (seen > 0) {
    for (i = 0; i < seen_cnt; i++)
      if (memcmp(seen[i], ipv6hdr + 8, 16) == 0)
        return;
  }
  if (seen_cnt <= MAX_SEEN)
    memcpy(seen[seen_cnt++], ipv6hdr + 8, 16);

  printf("Router: %s (MAC: %02x:%02x:%02x:%02x:%02x:%02x)\n", thc_ipv62notation(ipv6hdr + 8), data[6], data[7], data[8], data[9], data[10], data[11]);
  printf("  Priority: ");
  i = ipv6hdr[45] & 24;
  switch (i) {
  case 0:
    printf("medium\n");
    break;
  case 8:
    printf("high\n");
    break;
  case 16:
    printf("reserved value\n");
    break;
  case 24:
    printf("low\n");
    break;
  }
  printf("  Hop Count: %d\n", ipv6hdr[44]);
  printf("  Lifetime: %d, Reachable: %u, Retrans: %u\n", (ipv6hdr[46] << 8) + ipv6hdr[47], (ipv6hdr[48] << 24) + (ipv6hdr[49] << 16) + (ipv6hdr[50] << 8) + ipv6hdr[51],
         (ipv6hdr[52] << 24) + (ipv6hdr[53] << 16) + (ipv6hdr[54] << 8) + ipv6hdr[55]);
  printf("  Flags: ");
  if ((ipv6hdr[45] & 128) > 0)
    printf("managed ");
  else
    printf("NOTmanaged ");
  if ((ipv6hdr[45] & 64) > 0)
    printf("other ");
  else
    printf("NOTother ");
  if ((ipv6hdr[45] & 32) > 0)
    printf("home-agent ");
  else
    printf("NOThome-agent ");
  if ((ipv6hdr[45] & 4) > 0)
    printf("proxied ");
  else
    printf("NOTproxied ");
  if ((ipv6hdr[45] & 2) > 0)
    printf("RESERVED-2-BIT-SET ");
  if ((ipv6hdr[45] & 1) > 0)
    printf("RESERVED-1-BIT-SET");
  printf("\n");
  i = len - 56;
  ptr = ipv6hdr + 56;
  printf("  Options:\n");
  while (i > 0) {
    if (i < 8 || ptr[1] * 8 > i || ptr[1] == 0) {
      printf("Packet truncated!\n\n");
      return;
    }
    // (ptr[] << 24) + (ptr[] << 16) + (ptr[] << 8) + ptr[]
    switch (*ptr) {
    case 1:
      printf("    MAC: %02x:%02x:%02x:%02x:%02x:%02x\n", ptr[2], ptr[3], ptr[4], ptr[5], ptr[6], ptr[7]);
      break;
    case 3:
      if (ptr[1] != 4)
        printf("    Prefix: illegal\n");
      else {
        printf("    Prefix: %s/%d (Valid: %u, Preferred: %u)\n", thc_ipv62notation(ptr + 16), ptr[2], (ptr[4] << 24) + (ptr[5] << 16) + (ptr[6] << 8) + ptr[7],
               (ptr[8] << 24) + (ptr[9] << 16) + (ptr[10] << 8) + ptr[11]);
        printf("      Flags:");
        if ((ptr[3] & 128) > 0)
          printf(" On-Link");
        else
          printf(" NOT-on-link");
        if ((ptr[3] & 64) > 0)
          printf(" Autoconfig");
        else
          printf(" NOT-autoconfig");
        if ((ptr[3] & 32) > 0)
          printf(" Router-Address");
        else
          printf(" NOT-Router-Address");
        if ((ptr[3] & 31) > 0)
          printf(" RESERVED-BITS-SET-%d", ptr[3] & 63);
        printf("\n");
      }
      break;
    case 5:
      printf("    MTU: %d\n", (ptr[4] << 24) + (ptr[5] << 16) + (ptr[6] << 8) + ptr[7]);
      break;
    case 7:
      printf("    Advertisement Interval: %d\n", (ptr[4] << 24) + (ptr[5] << 16) + (ptr[6] << 8) + ptr[7]);
      break;
    case 8:
      printf("    Home Agent Preference: %d %d\n", (ptr[4] << 8) + (ptr[5]), (ptr[6] << 8) + ptr[7]);
      break;
    case 24:
      if (ptr[1] != 3 && ptr[1] != 2)
        printf("    Route: illegal\n");
      else {
        memset(tmpbuf, 0, sizeof(tmpbuf));
        memcpy(tmpbuf, ptr + 8, 8);
        printf("    Route: %s/%d (Lifetime: %u)\n", thc_ipv62notation(tmpbuf), ptr[2], (ptr[4] << 24) + (ptr[5] << 16) + (ptr[6] << 8) + ptr[7]);
        printf("      Priority:");
        k = ptr[3] & 24;
        switch (k) {
        case 0:
          printf("medium\n");
          break;
        case 8:
          printf("high\n");
          break;
        case 16:
          printf("reserved value\n");
          break;
        case 24:
          printf("low\n");
          break;
        }
      }
      break;
    case 31:
      ptr2 = ptr + 9;
      while (*ptr2 != 0) {
        if (*ptr2 < 32 && *ptr2 > 0)
          *ptr2 = '.';
        ptr2++;
      }
      printf("    DNS Searchlist: %s (Lifetime: %u)\n", ptr + 9, (ptr[4] << 24) + (ptr[5] << 16) + (ptr[6] << 8) + ptr[7]);
      break;
    case 25:
      if (ptr[1] != 3)
        printf("    DNS: illegal\n");
      else {
        printf("    DNS: %s (Lifetime: %u/%u)\n", thc_ipv62notation(ptr + 8), (ptr[4] << 24) + (ptr[5] << 16) + (ptr[6] << 8) + ptr[7],
               (ptr[8] << 24) + (ptr[9] << 16) + (ptr[10] << 8) + ptr[11]);
      }
      break;
    default:
      printf("    Unknown Option Type: %d (size: %d bytes)\n", ptr[0], ptr[1] * 8);
    }
    i -= ptr[1] * 8;
    ptr += ptr[1] * 8;
  }

  printf("\n");
}

void clean_exit(int sig) {
  exit(0);
}

int main(int argc, char *argv[]) {
  char *interface, string[] = "ip6 and icmp6";
  unsigned char *mac6, buf[512];
  unsigned char *dst = thc_resolve6("ff02::2"), *src = NULL;
  int i;
  unsigned char *pkt = NULL;
  int pkt_len = 0;
  int rawmode = 0;
  pcap_t *p;

  if (argc < 2 || strncmp(argv[1], "-h", 2) == 0)
    help(argv[0]);

  while ((i = getopt(argc, argv, "rS:h")) >= 0) {
    switch (i) {
    case 'r':
      thc_ipv6_rawmode(1);
      rawmode = 1;
      break;
    case 'h':
      help(argv[0]);
      break;
    case 'S':
      if ((src = thc_resolve6(optarg)) == NULL) {
        fprintf(stderr, "Error: could not resolve %s\n", optarg);
        return -1;
      }
    default:
      fprintf(stderr, "Error: invalid option %c\n", i);
      exit(-1);
    }
  }

  interface = argv[optind];
  if ((mac6 = thc_get_own_mac(interface)) == NULL) {
    fprintf(stderr, "Error: invalid interface %s\n", interface);
    exit(-1);
  }
  if (argc - optind > 1 && argv[optind + 1] != NULL)
    dst = thc_resolve6(argv[optind + 1]);

  memset(buf, 0, sizeof(buf));
  buf[0] = 1;
  buf[1] = 1;
  memcpy(buf + 2, mac6, 6);
  i = 8;
  memset(seen, 0, sizeof(seen));

  if ((p = thc_pcap_init(interface, string)) == NULL) {
    fprintf(stderr, "Error: could not capture on interface %s with string %s\n", interface, string);
    exit(-1);
  }

  if ((pkt = thc_create_ipv6_extended(interface, PREFER_LINK, &pkt_len, src, dst, 255, 0, 0, 0xe0, 0)) == NULL)
    return -1;
  if (thc_add_icmp6(pkt, &pkt_len, ICMP6_ROUTERSOL, 0, 0, buf, i, 0) < 0)
    return -1;
  if (thc_generate_and_send_pkt(interface, mac6, NULL, pkt, &pkt_len) < 0)
    return -1;

  signal(SIGALRM, clean_exit);
  alarm(5);
  while (1) {
    while (thc_pcap_check(p, (char *) dump_ra_reply, NULL) > 0);
    usleep(100);
  }
  return 0;
}