int
main(int argc, char *argv[])
{
int c, len;
libnet_t *l;
libnet_ptag_t t;
u_char *value;
u_char values[100];
u_short tmp;
u_long tmp2;
char *device = NULL;
char errbuf[LIBNET_ERRBUF_SIZE];
printf("libnet 1.1 packet shaping: CDP[link]\n");
/*
* Initialize the library. Root priviledges are required.
*/
l = libnet_init(
LIBNET_LINK, /* injection type */
device, /* network interface */
errbuf); /* errbuf */
if (l == NULL)
{
fprintf(stderr, "libnet_init() failed: %s", errbuf);
exit(EXIT_FAILURE);
}
value = "switch";
len = strlen(value);
t = libnet_build_cdp(
1, /* version */
30, /* time to live */
0, /* checksum */
LIBNET_CDP_DEVID, /* type */
len, /* length */
value, /* value */
NULL, /* payload */
0, /* payload size */
l, /* libnet handle */
0); /* libnet id */
if (t == -1)
{
fprintf(stderr, "Can't build CDP header: %s\n", libnet_geterror(l));
goto bad;
}
memset(values, 0, sizeof(values));
tmp = htons(LIBNET_CDP_PORTID);
memcpy(values, &tmp, 2);
tmp = htons(0x0014);
memcpy(values + 2, &tmp, 2);
memcpy(values + 4, (u_char *)"FastEthernet0/20", 16);
t = libnet_build_data(
values,
20,
l,
0);
if (t == -1)
{
fprintf(stderr, "Can't build CDP data: %s\n", libnet_geterror(l));
goto bad;
}
memset(values, 0, sizeof(values));
tmp = htons(LIBNET_CDP_CAPABIL);
memcpy(values, &tmp, 2);
tmp = htons(0x0008);
memcpy(values + 2, &tmp, 2);
tmp2 = htonl((LIBNET_CDP_CAP_L2S | LIBNET_CDP_CAP_L2B));
memcpy(values + 4, &tmp2, 4);
t = libnet_build_data(
values,
8,
l,
0);
if (t == -1)
{
fprintf(stderr, "Can't build CDP data: %s\n", libnet_geterror(l));
goto bad;
}
memset(values, 0, sizeof(values));
tmp = htons(LIBNET_CDP_VERSION);
memcpy(values, &tmp, 2);
tmp = htons(0x001f);
memcpy(values + 2, &tmp, 2);
memcpy(values + 4, (u_char *)"ABCDEFGHIJKLMNOPQRSTUVWXYZ", 26);
t = libnet_build_data(
values,
31,
l,
0);
if (t == -1)
{
fprintf(stderr, "Can't build CDP data: %s\n", libnet_geterror(l));
goto bad;
}
memset(values, 0, sizeof(values));
tmp = htons(LIBNET_CDP_PLATFORM);
memcpy(values, &tmp, 2);
tmp = htons(0x0015);
memcpy(values + 2, &tmp, 2);
memcpy(values + 4, (u_char *)"cisco WS-C2924-XL", 17);
t = libnet_build_data(
values,
21,
l,
0);
if (t == -1)
{
fprintf(stderr, "Can't build CDP data: %s\n", libnet_geterror(l));
goto bad;
}
t = libnet_build_ethernet(
enet_dst, /* ethernet destination */
enet_src, /* ethernet source */
0x2000, /* protocol type */
NULL, /* payload */
0, /* payload size */
l, /* libnet handle */
0); /* libnet id */
if (t == -1)
{
fprintf(stderr, "Can't build ethernet header: %s\n", libnet_geterror(l));
goto bad;
}
/*
* Write it to the wire.
*/
c = libnet_write(l);
if (c == -1)
{
fprintf(stderr, "Write error: %s\n", libnet_geterror(l));
goto bad;
}
else
{
fprintf(stderr, "Wrote %d byte CDP packet; check the wire.\n", c);
}
libnet_destroy(l);
return (EXIT_SUCCESS);
bad:
libnet_destroy(l);
return (EXIT_FAILURE);
}
int
main(int argc, char *argv[])
{
int c, len, index;
libnet_t *l;
libnet_ptag_t t;
u_char *value;
u_char values[100];
u_short tmp;
char errbuf[LIBNET_ERRBUF_SIZE];
u_int8_t oui[3] = { 0x00, 0x00, 0x0c };
u_int8_t cdp_mac[6] = {0x01, 0x0, 0xc, 0xcc, 0xcc, 0xcc};
if (argc != 3)
{
fprintf(stderr, "usage %s device device-id\n", argv[0]);
return (EXIT_FAILURE);
}
fprintf(stderr, "cdppoke...\n");
l = libnet_init(LIBNET_LINK, argv[1], errbuf);
if (l == NULL)
{
fprintf(stderr, "libnet_init() failed: %s", errbuf);
return (EXIT_FAILURE);
}
/* build the TLV's by hand until we get something better */
memset(values, 0, sizeof(values));
index = 0;
tmp = htons(LIBNET_CDP_VERSION);
memcpy(values, &tmp, 2);
index += 2;
tmp = htons(9); /* length of string below plus type and length fields */
memcpy(values + index, &tmp, 2);
index += 2;
memcpy(values + index, (u_char *)"1.1.1", 5);
index += 5;
/* this TLV is handled by the libnet builder */
value = argv[2];
len = strlen(argv[2]);
/* build CDP header */
t = libnet_build_cdp(
1, /* version */
30, /* time to live */
0x0, /* checksum */
0x1, /* type */
len, /* length */
value, /* value */
values, /* payload */
index, /* payload size */
l, /* libnet context */
0); /* libnet ptag */
if (t == -1)
{
fprintf(stderr, "Can't build CDP header: %s\n", libnet_geterror(l));
goto bad;
}
/* build 802.2 header */
t = libnet_build_802_2snap(
LIBNET_SAP_SNAP, /* SAP SNAP code */
LIBNET_SAP_SNAP, /* SAP SNAP code */
0x03, /* control */
oui, /* OUI */
0x2000, /* upper layer protocol type */
NULL, /* payload */
0, /* payload size */
l, /* libnet context */
0); /* libnet ptag */
if (t == -1)
{
fprintf(stderr, "Can't build SNAP header: %s\n", libnet_geterror(l));
goto bad;
}
/* build 802.3 header */
t = libnet_build_802_3(
cdp_mac, /* ethernet destination */
(u_int8_t *)libnet_get_hwaddr(l), /* ethernet source */
LIBNET_802_2_H + LIBNET_802_2SNAP_H + LIBNET_CDP_H, /* packet len */
NULL, /* payload */
0, /* payload size */
l, /* libnet context */
0); /* libnet ptag */
if (t == -1)
{
fprintf(stderr, "Can't build 802.3 header: %s\n", libnet_geterror(l));
goto bad;
}
/* write the packet out */
c = libnet_write(l);
if (c == -1)
{
fprintf(stderr, "Write error: %s\n", libnet_geterror(l));
goto bad;
}
else
{
fprintf(stderr, "Wrote %d byte CDP frame \"%s\"\n", c, argv[2]);
}
libnet_destroy(l);
return (EXIT_SUCCESS);
bad:
libnet_destroy(l);
return (EXIT_FAILURE);
}
