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 1.1.2.2 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 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 */ 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 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 */ 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 } 251 252 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 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 */ 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 304 septel_setnonblock(pcap_t *p, int nonblock, char *errbuf) 305 { 306 return (0); 307 } 308