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