1/*
2 * pcap-septel.c: Packet capture interface for Intel/Septel card.
3 *
4 * The functionality of this code attempts to mimic that of pcap-linux as much
5 * as possible.  This code is compiled in several different ways depending on
6 * whether SEPTEL_ONLY and HAVE_SEPTEL_API are defined.  If HAVE_SEPTEL_API is
7 * not defined it should not get compiled in, otherwise if SEPTEL_ONLY is
8 * defined then the 'septel_' function calls are renamed to 'pcap_'
9 * equivalents.  If SEPTEL_ONLY is not defined then nothing is altered - the
10 * septel_ functions will be called as required from their
11 * pcap-linux/equivalents.
12 *
13 * Authors: Gilbert HOYEK (gil_hoyek@hotmail.com), Elias M. KHOURY
14 * (+961 3 485243)
15 */
16
17#ifndef lint
18static const char rcsid[] _U_ =
19    "@(#) $Header: /tcpdump/master/libpcap/pcap-septel.c,v 1.1.2.2 2005/06/21 01:03:23 guy Exp $";
20#endif
21
22#ifdef HAVE_CONFIG_H
23#include "config.h"
24#endif
25
26#include <sys/param.h>
27
28#include <stdlib.h>
29#include <string.h>
30#include <errno.h>
31
32#include "pcap-int.h"
33
34#include <ctype.h>
35#include <netinet/in.h>
36#include <sys/mman.h>
37#include <sys/socket.h>
38#include <sys/types.h>
39#include <unistd.h>
40
41#ifdef HAVE_SEPTEL_API
42#include <msg.h>
43#include <ss7_inc.h>
44#include <sysgct.h>
45#include <pack.h>
46#include <system.h>
47#endif /* HAVE_SEPTEL_API */
48
49#ifdef SEPTEL_ONLY
50/* This code is required when compiling for a Septel device only. */
51#include "pcap-septel.h"
52
53/* Replace dag function names with pcap equivalent. */
54#define septel_open_live pcap_open_live
55#define septel_platform_finddevs pcap_platform_finddevs
56#endif /* SEPTEL_ONLY */
57
58static int septel_setfilter(pcap_t *p, struct bpf_program *fp);
59static int septel_stats(pcap_t *p, struct pcap_stat *ps);
60static int septel_setnonblock(pcap_t *p, int nonblock, char *errbuf);
61
62static void septel_platform_close(pcap_t *p) {
63
64}
65
66
67
68/*
69 *  Read at most max_packets from the capture queue and call the callback
70 *  for each of them. Returns the number of packets handled, -1 if an
71 *  error occured, or -2 if we were told to break out of the loop.
72 */
73static int septel_read(pcap_t *p, int cnt, pcap_handler callback, u_char *user) {
74
75  HDR *h;
76  MSG *m;
77  int processed = 0 ;
78  int t = 0 ;
79
80  /* identifier for the message queue of the module(upe) from which we are capturing
81   * packets.These IDs are defined in system.txt . By default it is set to 0x2d
82   * so change it to 0xdd for technical reason and therefore the module id for upe becomes:
83   * LOCAL        0xdd           * upe - Example user part task */
84  unsigned int id = 0xdd;
85
86  /* process the packets */
87  do  {
88
89    unsigned short packet_len = 0;
90    int caplen = 0;
91    int counter = 0;
92    struct pcap_pkthdr   pcap_header;
93    u_char *dp ;
94
95    /*
96     * Has "pcap_breakloop()" been called?
97     */
98loop:
99    if (p->break_loop) {
100      /*
101       * Yes - clear the flag that indicates that
102       * it has, and return -2 to indicate that
103       * we were told to break out of the loop.
104       */
105      p->break_loop = 0;
106      return -2;
107    }
108
109    /*repeat until a packet is read
110     *a NULL message means :
111     * when no packet is in queue or all packets in queue already read */
112    do  {
113      /* receive packet in non-blocking mode
114       * GCT_grab is defined in the septel library software */
115      h = GCT_grab(id);
116
117      m = (MSG*)h;
118      /* a couter is added here to avoid an infinite loop
119       * that will cause our capture program GUI to freeze while waiting
120       * for a packet*/
121      counter++ ;
122
123    }
124    while  ((m == NULL)&& (counter< 100)) ;
125
126    if (m != NULL) {
127
128      t = h->type ;
129
130      /* catch only messages with type = 0xcf00 or 0x8f01 corrsponding to ss7 messages*/
131      /* XXX = why not use API_MSG_TX_REQ for 0xcf00 and API_MSG_RX_IND
132       * for 0x8f01? */
133      if ((t != 0xcf00) && (t != 0x8f01)) {
134        relm(h);
135        goto loop ;
136      }
137
138      /* XXX - is API_MSG_RX_IND for an MTP2 or MTP3 message? */
139      dp = get_param(m);/* get pointer to MSG parameter area (m->param) */
140      packet_len = m->len;
141      caplen =  p->snapshot ;
142
143
144      if (caplen > packet_len) {
145
146        caplen = packet_len;
147      }
148      /* Run the packet filter if there is one. */
149      if ((p->fcode.bf_insns == NULL) || bpf_filter(p->fcode.bf_insns, dp, packet_len, caplen)) {
150
151
152        /*  get a time stamp , consisting of :
153         *
154         *  pcap_header.ts.tv_sec:
155         *  ----------------------
156         *   a UNIX format time-in-seconds when he packet was captured,
157         *   i.e. the number of seconds since Epoch time (January 1,1970, 00:00:00 GMT)
158         *
159         *  pcap_header.ts.tv_usec :
160         *  ------------------------
161         *   the number of microseconds since that second
162         *   when the packet was captured
163         */
164
165        (void)gettimeofday(&pcap_header.ts, NULL);
166
167        /* Fill in our own header data */
168        pcap_header.caplen = caplen;
169        pcap_header.len = packet_len;
170
171        /* Count the packet. */
172        p->md.stat.ps_recv++;
173
174        /* Call the user supplied callback function */
175        callback(user, &pcap_header, dp);
176
177        processed++ ;
178
179      }
180      /* after being processed the packet must be
181       *released in order to receive another one */
182      relm(h);
183    }else
184      processed++;
185
186  }
187  while (processed < cnt) ;
188
189  return processed ;
190}
191
192
193static int
194septel_inject(pcap_t *handle, const void *buf _U_, size_t size _U_)
195{
196  strlcpy(handle->errbuf, "Sending packets isn't supported on Septel cards",
197          PCAP_ERRBUF_SIZE);
198  return (-1);
199}
200
201/*
202 *  Get a handle for a live capture from the given Septel device.  Always pass a NULL device
203 *  The promisc flag is ignored because Septel cards have built-in tracing.
204 *  The to_ms parameter is also ignored as it is
205 *  not supported in hardware.
206 *
207 *  See also pcap(3).
208 */
209pcap_t *septel_open_live(const char *device, int snaplen, int promisc, int to_ms, char *ebuf) {
210  pcap_t *handle;
211
212  handle = malloc(sizeof(*handle));
213  if (handle == NULL) {
214    snprintf(ebuf, PCAP_ERRBUF_SIZE, "malloc %s: %s", device, pcap_strerror(errno));
215    return NULL;
216  }
217
218  /* Initialize some components of the pcap structure. */
219
220  memset(handle, 0, sizeof(*handle));
221
222  handle->snapshot = snaplen;
223
224  handle->linktype = DLT_MTP2;
225
226  handle->bufsize = 0;
227
228  /*
229   * "select()" and "poll()" don't work on Septel queues
230   */
231  handle->selectable_fd = -1;
232
233  handle->read_op = septel_read;
234  handle->inject_op = septel_inject;
235  handle->setfilter_op = septel_setfilter;
236  handle->set_datalink_op = NULL; /* can't change data link type */
237  handle->getnonblock_op = pcap_getnonblock_fd;
238  handle->setnonblock_op = septel_setnonblock;
239  handle->stats_op = septel_stats;
240  handle->close_op = septel_platform_close;
241
242  return handle;
243
244fail:
245  if (handle != NULL) {
246    free(handle);
247  }
248
249  return NULL;
250}
251
252static int septel_stats(pcap_t *p, struct pcap_stat *ps) {
253  /*p->md.stat.ps_recv = 0;*/
254  /*p->md.stat.ps_drop = 0;*/
255
256  *ps = p->md.stat;
257
258  return 0;
259}
260
261
262int
263septel_platform_finddevs(pcap_if_t **devlistp, char *errbuf)
264{
265unsigned char *p;
266  const char description[512]= "Intel/Septel device";
267  char name[512]="septel" ;
268  int ret = 0;
269  pcap_add_if(devlistp,name,0,description,errbuf);
270
271  return (ret);
272}
273
274
275/*
276 * Installs the given bpf filter program in the given pcap structure.  There is
277 * no attempt to store the filter in kernel memory as that is not supported
278 * with Septel cards.
279 */
280static int septel_setfilter(pcap_t *p, struct bpf_program *fp) {
281  if (!p)
282    return -1;
283  if (!fp) {
284    strncpy(p->errbuf, "setfilter: No filter specified",
285	    sizeof(p->errbuf));
286    return -1;
287  }
288
289  /* Make our private copy of the filter */
290
291  if (install_bpf_program(p, fp) < 0) {
292    snprintf(p->errbuf, sizeof(p->errbuf),
293	     "malloc: %s", pcap_strerror(errno));
294    return -1;
295  }
296
297  p->md.use_bpf = 0;
298
299  return (0);
300}
301
302
303static int
304septel_setnonblock(pcap_t *p, int nonblock, char *errbuf)
305{
306  return (0);
307}
308