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 (at) 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 1.4 2008-04-14 20:40:58 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 #include <msg.h> 42 #include <ss7_inc.h> 43 #include <sysgct.h> 44 #include <pack.h> 45 #include <system.h> 46 47 #include "pcap-septel.h" 48 49 static int septel_setfilter(pcap_t *p, struct bpf_program *fp); 50 static int septel_stats(pcap_t *p, struct pcap_stat *ps); 51 static int septel_setnonblock(pcap_t *p, int nonblock, char *errbuf); 52 53 /* 54 * Private data for capturing on Septel devices. 55 */ 56 struct pcap_septel { 57 struct pcap_stat stat; 58 } 59 60 /* 61 * Read at most max_packets from the capture queue and call the callback 62 * for each of them. Returns the number of packets handled, -1 if an 63 * error occured, or -2 if we were told to break out of the loop. 64 */ 65 static int septel_read(pcap_t *p, int cnt, pcap_handler callback, u_char *user) { 66 67 struct pcap_septel *ps = p->priv; 68 HDR *h; 69 MSG *m; 70 int processed = 0 ; 71 int t = 0 ; 72 73 /* identifier for the message queue of the module(upe) from which we are capturing 74 * packets.These IDs are defined in system.txt . By default it is set to 0x2d 75 * so change it to 0xdd for technical reason and therefore the module id for upe becomes: 76 * LOCAL 0xdd * upe - Example user part task */ 77 unsigned int id = 0xdd; 78 79 /* process the packets */ 80 do { 81 82 unsigned short packet_len = 0; 83 int caplen = 0; 84 int counter = 0; 85 struct pcap_pkthdr pcap_header; 86 u_char *dp ; 87 88 /* 89 * Has "pcap_breakloop()" been called? 90 */ 91 loop: 92 if (p->break_loop) { 93 /* 94 * Yes - clear the flag that indicates that 95 * it has, and return -2 to indicate that 96 * we were told to break out of the loop. 97 */ 98 p->break_loop = 0; 99 return -2; 100 } 101 102 /*repeat until a packet is read 103 *a NULL message means : 104 * when no packet is in queue or all packets in queue already read */ 105 do { 106 /* receive packet in non-blocking mode 107 * GCT_grab is defined in the septel library software */ 108 h = GCT_grab(id); 109 110 m = (MSG*)h; 111 /* a couter is added here to avoid an infinite loop 112 * that will cause our capture program GUI to freeze while waiting 113 * for a packet*/ 114 counter++ ; 115 116 } 117 while ((m == NULL)&& (counter< 100)) ; 118 119 if (m != NULL) { 120 121 t = h->type ; 122 123 /* catch only messages with type = 0xcf00 or 0x8f01 corrsponding to ss7 messages*/ 124 /* XXX = why not use API_MSG_TX_REQ for 0xcf00 and API_MSG_RX_IND 125 * for 0x8f01? */ 126 if ((t != 0xcf00) && (t != 0x8f01)) { 127 relm(h); 128 goto loop ; 129 } 130 131 /* XXX - is API_MSG_RX_IND for an MTP2 or MTP3 message? */ 132 dp = get_param(m);/* get pointer to MSG parameter area (m->param) */ 133 packet_len = m->len; 134 caplen = p->snapshot ; 135 136 137 if (caplen > packet_len) { 138 139 caplen = packet_len; 140 } 141 /* Run the packet filter if there is one. */ 142 if ((p->fcode.bf_insns == NULL) || bpf_filter(p->fcode.bf_insns, dp, packet_len, caplen)) { 143 144 145 /* get a time stamp , consisting of : 146 * 147 * pcap_header.ts.tv_sec: 148 * ---------------------- 149 * a UNIX format time-in-seconds when he packet was captured, 150 * i.e. the number of seconds since Epoch time (January 1,1970, 00:00:00 GMT) 151 * 152 * pcap_header.ts.tv_usec : 153 * ------------------------ 154 * the number of microseconds since that second 155 * when the packet was captured 156 */ 157 158 (void)gettimeofday(&pcap_header.ts, NULL); 159 160 /* Fill in our own header data */ 161 pcap_header.caplen = caplen; 162 pcap_header.len = packet_len; 163 164 /* Count the packet. */ 165 ps->stat.ps_recv++; 166 167 /* Call the user supplied callback function */ 168 callback(user, &pcap_header, dp); 169 170 processed++ ; 171 172 } 173 /* after being processed the packet must be 174 *released in order to receive another one */ 175 relm(h); 176 }else 177 processed++; 178 179 } 180 while (processed < cnt) ; 181 182 return processed ; 183 } 184 185 186 static int 187 septel_inject(pcap_t *handle, const void *buf _U_, size_t size _U_) 188 { 189 strlcpy(handle->errbuf, "Sending packets isn't supported on Septel cards", 190 PCAP_ERRBUF_SIZE); 191 return (-1); 192 } 193 194 /* 195 * Activate a handle for a live capture from the given Septel device. Always pass a NULL device 196 * The promisc flag is ignored because Septel cards have built-in tracing. 197 * The timeout is also ignored as it is not supported in hardware. 198 * 199 * See also pcap(3). 200 */ 201 static pcap_t *septel_activate(pcap_t* handle) { 202 /* Initialize some components of the pcap structure. */ 203 handle->linktype = DLT_MTP2; 204 205 handle->bufsize = 0; 206 207 /* 208 * "select()" and "poll()" don't work on Septel queues 209 */ 210 handle->selectable_fd = -1; 211 212 handle->read_op = septel_read; 213 handle->inject_op = septel_inject; 214 handle->setfilter_op = septel_setfilter; 215 handle->set_datalink_op = NULL; /* can't change data link type */ 216 handle->getnonblock_op = pcap_getnonblock_fd; 217 handle->setnonblock_op = septel_setnonblock; 218 handle->stats_op = septel_stats; 219 220 return 0; 221 } 222 223 pcap_t *septel_create(const char *device, char *ebuf, int *is_ours) { 224 const char *cp; 225 pcap_t *p; 226 227 /* Does this look like the Septel device? */ 228 cp = strrchr(device, '/'); 229 if (cp == NULL) 230 cp = device; 231 if (strcmp(cp, "septel") != 0) { 232 /* Nope, it's not "septel" */ 233 *is_ours = 0; 234 return NULL; 235 } 236 237 /* OK, it's probably ours. */ 238 *is_ours = 1; 239 240 p = pcap_create_common(device, ebuf, sizeof (struct pcap_septel)); 241 if (p == NULL) 242 return NULL; 243 244 p->activate_op = septel_activate; 245 return p; 246 } 247 248 static int septel_stats(pcap_t *p, struct pcap_stat *ps) { 249 struct pcap_septel *handlep = p->priv; 250 /*handlep->stat.ps_recv = 0;*/ 251 /*handlep->stat.ps_drop = 0;*/ 252 253 *ps = handlep->stat; 254 255 return 0; 256 } 257 258 259 int 260 septel_findalldevs(pcap_if_t **devlistp, char *errbuf) 261 { 262 unsigned char *p; 263 const char description[512]= "Intel/Septel device"; 264 char name[512]="septel" ; 265 int ret = 0; 266 pcap_add_if(devlistp,name,0,description,errbuf); 267 268 return (ret); 269 } 270 271 272 /* 273 * Installs the given bpf filter program in the given pcap structure. There is 274 * no attempt to store the filter in kernel memory as that is not supported 275 * with Septel cards. 276 */ 277 static int septel_setfilter(pcap_t *p, struct bpf_program *fp) { 278 if (!p) 279 return -1; 280 if (!fp) { 281 strncpy(p->errbuf, "setfilter: No filter specified", 282 sizeof(p->errbuf)); 283 return -1; 284 } 285 286 /* Make our private copy of the filter */ 287 288 if (install_bpf_program(p, fp) < 0) { 289 snprintf(p->errbuf, sizeof(p->errbuf), 290 "malloc: %s", pcap_strerror(errno)); 291 return -1; 292 } 293 294 return (0); 295 } 296 297 298 static int 299 septel_setnonblock(pcap_t *p, int nonblock, char *errbuf) 300 { 301 fprintf(errbuf, PCAP_ERRBUF_SIZE, "Non-blocking mode not supported on Septel devices"); 302 return (-1); 303 } 304
