-
Notifications
You must be signed in to change notification settings - Fork 0
/
packet.c
278 lines (248 loc) · 7.61 KB
/
packet.c
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
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
/*
*
* Copyright (C) 2010 Todd Merritt <redsox38@gmail.com>
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
*/
#include "panoptes.h"
#include "discover.h"
#include <getopt.h>
#include <string.h>
#ifdef HAVE_PCAP_H
#include <pcap.h>
#endif
#include <errno.h>
#include <sys/types.h>
#include "packet.h"
#ifdef WITH_P0F
#include "p0f-query.h"
#include <sys/un.h>
#include <sys/socket.h>
#endif
#include <errno.h>
pcap_t *pcap_handle;
char errbuf[PCAP_ERRBUF_SIZE];
extern port_list_t *auto_port_list;
extern port_list_t *ignore_port_list;
#ifdef WITH_P0F
extern char *p0f_sock_path;
int run_p0f_query(struct p0f_query *qry, struct p0f_response *resp)
{
int p0f_sock, rc = 0;
struct sockaddr_un x;
if (p0f_sock_path != NULL) {
if ((p0f_sock = socket(PF_UNIX, SOCK_STREAM, 0)) < 0) {
syslog(LOG_NOTICE, "socket: %s", strerror(errno));
return(rc);
} else {
memset(&x, 0, sizeof(x));
x.sun_family = AF_UNIX;
strncpy(x.sun_path, p0f_sock_path, strlen(p0f_sock_path));
syslog(LOG_DEBUG, "Got p0f socket path: %s", x.sun_path);
if (connect(p0f_sock, (struct sockaddr*)&x, sizeof(x)) < 0) {
syslog(LOG_NOTICE, "connect: %s", strerror(errno));
close(p0f_sock);
return(rc);
}
}
}
if (write(p0f_sock, qry, sizeof(struct p0f_query)) < 0) {
syslog(LOG_NOTICE, "p0f write: magic: %d %d bytes %s", qry->magic, sizeof(struct p0f_query), strerror(errno));
} else {
if (read(p0f_sock, resp, sizeof(struct p0f_response)) < 0) {
syslog(LOG_NOTICE, "p0f read: %s", strerror(errno));
} else {
if (resp->magic != QUERY_MAGIC) {
syslog(LOG_DEBUG, "invalid magic %d", resp->magic);
} else {
if (resp->type == RESP_BADQUERY) {
syslog(LOG_DEBUG, "bad query");
} else {
if (resp->type == RESP_NOMATCH) {
syslog(LOG_DEBUG, "no match in cache");
} else {
if (!resp->genre[0]) {
syslog(LOG_DEBUG, "genre is null");
} else {
syslog(LOG_DEBUG, "genre is %s", resp->genre);
rc = 1;
}
}
}
}
}
}
shutdown(p0f_sock, 2);
close(p0f_sock);
return(rc);
}
#endif
/*
function passed to pcap_loop to read processed packets
that match the filter.
sends matched packets to database for later interactive
processing.
*/
void read_packet(u_char *args, const struct pcap_pkthdr *hdr,
const u_char *packet)
{
const struct sniff_ethernet *eth;
const struct sniff_ip *ip;
const struct sniff_tcp *tcp;
const struct sniff_udp *udp;
const char *payload;
char os_genre[20];
char os_detail[40];
int size_ip, size_tcp, size_udp, size_payload;
char *src, *dst;
#ifdef WITH_P0F
struct p0f_query p0f_query;
struct p0f_response p0f_response;
#endif
eth = (struct sniff_ethernet*)(packet);
ip = (struct sniff_ip *)(packet + SIZE_ETHER);
size_ip = IP_HL(ip)*4;
src = strdup(inet_ntoa(ip->ip_src));
dst = strdup(inet_ntoa(ip->ip_dst));
if (ip->ip_p == IPPROTO_TCP) {
tcp = (struct sniff_tcp*)(packet + SIZE_ETHER + size_ip);
size_tcp = TH_OFF(tcp)*4;
if (is_in_port_list(ntohs(tcp->th_sport), ignore_port_list)) {
syslog(LOG_DEBUG, "ignoring %d", ntohs(tcp->th_sport));
} else {
/* see if we've already seen this addr/port */
if (!seen_entry(ip->ip_src, ntohs(tcp->th_sport))) {
insert_seen_node(ip->ip_src, ntohs(tcp->th_sport));
snprintf(os_genre, strlen("unknown") + 1, "%s", "unknown");
snprintf(os_detail, strlen("unknown") + 1, "%s", "unknown");
#ifdef WITH_P0F
if (p0f_sock_path != NULL) {
/* get OS from p0f if needed and a socket is defined */
memset(&p0f_query, 0, sizeof(struct p0f_query));
memset(&p0f_response, 0, sizeof(struct p0f_response));
p0f_query.magic = QUERY_MAGIC;
p0f_query.id = 0x12345678;
p0f_query.type = QTYPE_FINGERPRINT;
p0f_query.src_ad = ip->ip_src.s_addr;
p0f_query.dst_ad = ip->ip_dst.s_addr;
p0f_query.src_port = ntohs(tcp->th_sport);
p0f_query.dst_port = ntohs(tcp->th_dport);
if (run_p0f_query(&p0f_query, &p0f_response)) {
snprintf(os_genre, strlen(p0f_response.genre), "%s",
p0f_response.genre);
snprintf(os_detail, strlen(p0f_response.detail), "%s",
p0f_response.detail);
}
}
#endif
syslog(LOG_DEBUG, "TCP From %s:%d To %s:%d\n", src,
ntohs(tcp->th_sport), dst, ntohs(tcp->th_dport));
/* flip src and dst since our src is the host sending the SYN/ACK */
/* AKA the host being connected to */
if (is_in_port_list(ntohs(tcp->th_sport), auto_port_list)) {
syslog(LOG_DEBUG, "auto accepting %d", ntohs(tcp->th_sport));
add_monitor_port(src, ntohs(tcp->th_sport), "tcp",
os_genre, os_detail);
} else {
add_discovered_connection(dst, ntohs(tcp->th_dport),
src, ntohs(tcp->th_sport),
"tcp", os_genre, os_detail);
}
}
}
}
/*
} else if (ip->ip_p == IPPROTO_UDP) {
udp = (struct sniff_udp*)(packet + SIZE_ETHER + size_ip);
size_udp = udp->uh_len;
syslog(LOG_DEBUG, "UDP From %s:%d To %s:%d\n", src,
ntohs(udp->uh_sport), dst, ntohs(udp->uh_dport));
if (ntohs(udp->uh_sport < IPPORT_RESERVED)) {
add_discovered_connection(src, ntohs(udp->uh_sport),
dst, ntohs(udp->uh_dport),
"udp");
} else {
add_discovered_connection(dst, ntohs(udp->uh_dport),
src, ntohs(udp->uh_sport),
"udp");
}
*/
free(src);
free(dst);
return;
}
/* function called by discover on sig term */
void packet_term_handler()
{
if (pcap_handle)
pcap_close;
}
/*
function to read packets if we were given a device
to read from. Also the default if no pcap file
was given
*/
int init_packet_capture_live(char *dev)
{
if (dev) {
pcap_handle = pcap_open_live(dev, 1500, 1, 1000, errbuf);
}
if (!pcap_handle) {
syslog(LOG_ALERT, "Unable to open device %s: %s", dev, errbuf);
return(-1);
}
return(0);
}
/*
function called to read packets if we were given a previous pcap file
to read from
*/
int init_packet_capture_from_file(char *file)
{
if (file) {
pcap_handle = pcap_open_offline(file, errbuf);
}
if (!pcap_handle) {
syslog(LOG_ALERT, "Unable to open device %s: %s", file, errbuf);
return(-1);
}
return(0);
}
/*
set up filter and start capture
if reading from device,
function will not return
*/
void run_packet_capture()
{
struct bpf_program filter;
char filter_ex[] = "tcp[13] = 18 or udp";
if (pcap_handle) {
/* compile filter */
if (pcap_compile(pcap_handle, &filter, filter_ex, 0, 0) < 0) {
syslog(LOG_ALERT, "Couldn't parse filter %s: %s\n", filter_ex,
pcap_geterr(pcap_handle));
} else {
if (pcap_setfilter(pcap_handle, &filter) < 0) {
syslog(LOG_ALERT, "Couldn't parse filter %s: %s\n", filter_ex,
pcap_geterr(pcap_handle));
}
}
}
/* device ready, filter compiled. Here we go... */
if (pcap_handle) {
pcap_loop(pcap_handle, -1, read_packet, NULL);
}
}