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
18 static 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
58 static int septel_setfilter(pcap_t *p, struct bpf_program *fp);
59 static int septel_stats(pcap_t *p, struct pcap_stat *ps);
60 static int septel_setnonblock(pcap_t *p, int nonblock, char *errbuf);
61
septel_platform_close(pcap_t * p)62 static 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 */
septel_read(pcap_t * p,int cnt,pcap_handler callback,u_char * user)73 static 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 */
98 loop:
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
193 static int
septel_inject(pcap_t * handle,const void * buf _U_,size_t size _U_)194 septel_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 */
septel_open_live(const char * device,int snaplen,int promisc,int to_ms,char * ebuf)209 pcap_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
244 fail:
245 if (handle != NULL) {
246 free(handle);
247 }
248
249 return NULL;
250 }
251
septel_stats(pcap_t * p,struct pcap_stat * ps)252 static 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
262 int
septel_platform_finddevs(pcap_if_t ** devlistp,char * errbuf)263 septel_platform_finddevs(pcap_if_t **devlistp, char *errbuf)
264 {
265 unsigned 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 */
septel_setfilter(pcap_t * p,struct bpf_program * fp)280 static 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
303 static int
septel_setnonblock(pcap_t * p,int nonblock,char * errbuf)304 septel_setnonblock(pcap_t *p, int nonblock, char *errbuf)
305 {
306 return (0);
307 }
308