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