4 * Copyright (c) 1998 by Gilbert Ramirez <gram@alumni.rice.edu>
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version 2
9 * of the License, or (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
25 #include "file_wrappers.h"
32 /* This module reads the output of the EyeSDN USB S0/E1 ISDN probes
33 * They store HDLC frames of D and B channels in a binary format
36 * 1-6 Byte: EyeSDN - Magic
39 * Each Frame starts with the 0xff Flag byte
40 * - Bytes 0-2: timestamp (usec in network byte order)
41 * - Bytes 3-7: timestamp (40bits sec since 1970 in network byte order)
42 * - Byte 8: channel (0 for D channel, 1-30 for B1-B30)
43 * - Byte 9: Sender Bit 0(0 NT, 1 TE), Protocol in Bits 7:1, see enum
44 * - Byte 10-11: frame size in bytes
45 * - Byte 12-n: Frame Payload
47 * All multibyte values are represented in network byte order
48 * The frame is terminated with a flag character (0xff)
49 * bytes 0xff within a frame are escaped using the 0xfe escape character
50 * the byte following the escape character is decremented by two:
51 * so 0xfe 0xfd is actually a 0xff
52 * Characters that need to be escaped are 0xff and 0xfe
56 static int esc_read(guint8 *buf, int len, FILE_T fh)
61 for(i=0; i<len; i++) {
64 return -2; /* EOF or error */
66 return -1; /* error !!, read into next frame */
68 /* we need to escape */
80 /* Magic text to check for eyesdn-ness of file */
81 static const unsigned char eyesdn_hdr_magic[] =
82 { 'E', 'y', 'e', 'S', 'D', 'N'};
83 #define EYESDN_HDR_MAGIC_SIZE (sizeof(eyesdn_hdr_magic) / sizeof(eyesdn_hdr_magic[0]))
85 /* Size of a record header */
86 #define EYESDN_HDR_LENGTH 12
89 * XXX - is this the biggest packet we can get?
91 #define EYESDN_MAX_PACKET_LEN 16384
93 static gboolean eyesdn_read(wtap *wth, int *err, gchar **err_info,
95 static gboolean eyesdn_seek_read(wtap *wth, gint64 seek_off,
96 struct wtap_pkthdr *phdr, Buffer *buf, int *err, gchar **err_info);
97 static int read_eyesdn_rec(FILE_T fh, struct wtap_pkthdr *phdr, Buffer* buf,
98 int *err, gchar **err_info);
100 /* Seeks to the beginning of the next packet, and returns the
101 byte offset. Returns -1 on failure, and sets "*err" to the error
102 and "*err_info" to null or an additional error string. */
103 static gint64 eyesdn_seek_next_packet(wtap *wth, int *err, gchar **err_info)
108 while ((byte = file_getc(wth->fh)) != EOF) {
110 cur_off = file_tell(wth->fh);
113 *err = file_error(wth->fh, err_info);
120 *err = file_error(wth->fh, err_info);
124 int eyesdn_open(wtap *wth, int *err, gchar **err_info)
127 char magic[EYESDN_HDR_MAGIC_SIZE];
129 /* Look for eyesdn header */
130 errno = WTAP_ERR_CANT_READ;
131 bytes_read = file_read(&magic, sizeof magic, wth->fh);
132 if (bytes_read != sizeof magic) {
133 *err = file_error(wth->fh, err_info);
134 if (*err != 0 && *err != WTAP_ERR_SHORT_READ)
138 if (memcmp(magic, eyesdn_hdr_magic, EYESDN_HDR_MAGIC_SIZE) != 0)
141 wth->file_encap = WTAP_ENCAP_PER_PACKET;
142 wth->file_type_subtype = WTAP_FILE_TYPE_SUBTYPE_EYESDN;
143 wth->snapshot_length = 0; /* not known */
144 wth->subtype_read = eyesdn_read;
145 wth->subtype_seek_read = eyesdn_seek_read;
146 wth->tsprecision = WTAP_FILE_TSPREC_USEC;
151 /* Find the next packet and parse it; called from wtap_read(). */
152 static gboolean eyesdn_read(wtap *wth, int *err, gchar **err_info,
157 /* Find the next record */
158 offset = eyesdn_seek_next_packet(wth, err, err_info);
161 *data_offset = offset;
163 /* Parse the record */
164 return read_eyesdn_rec(wth->fh, &wth->phdr, wth->frame_buffer,
168 /* Used to read packets in random-access fashion */
170 eyesdn_seek_read(wtap *wth, gint64 seek_off, struct wtap_pkthdr *phdr,
171 Buffer *buf, int *err, gchar **err_info)
173 if (file_seek(wth->random_fh, seek_off, SEEK_SET, err) == -1)
176 return read_eyesdn_rec(wth->random_fh, phdr, buf, err, err_info);
179 /* Parses a record. */
181 read_eyesdn_rec(FILE_T fh, struct wtap_pkthdr *phdr, Buffer *buf, int *err,
184 union wtap_pseudo_header *pseudo_header = &phdr->pseudo_header;
185 guint8 hdr[EYESDN_HDR_LENGTH];
189 guint8 channel, direction;
193 /* Our file pointer should be at the summary information header
194 * for a packet. Read in that header and extract the useful
197 if (esc_read(hdr, EYESDN_HDR_LENGTH, fh) != EYESDN_HDR_LENGTH) {
198 *err = file_error(fh, err_info);
200 *err = WTAP_ERR_SHORT_READ;
204 /* extract information from header */
205 usecs = pntoh24(&hdr[0]);
211 secs = (secs << 8) | hdr[4];
212 secs = (secs << 8) | hdr[5];
213 secs = (secs << 8) | hdr[6];
214 secs = (secs << 8) | hdr[7];
218 pkt_len = pntoh16(&hdr[10]);
220 switch(direction >> 1) {
223 case EYESDN_ENCAP_ISDN: /* ISDN */
224 pseudo_header->isdn.uton = direction & 1;
225 pseudo_header->isdn.channel = channel;
226 if(channel) { /* bearer channels */
227 phdr->pkt_encap = WTAP_ENCAP_ISDN; /* recognises PPP */
228 pseudo_header->isdn.uton=!pseudo_header->isdn.uton; /* bug */
229 } else { /* D channel */
230 phdr->pkt_encap = WTAP_ENCAP_ISDN;
234 case EYESDN_ENCAP_MSG: /* Layer 1 message */
235 phdr->pkt_encap = WTAP_ENCAP_LAYER1_EVENT;
236 pseudo_header->l1event.uton = (direction & 1);
239 case EYESDN_ENCAP_LAPB: /* X.25 via LAPB */
240 phdr->pkt_encap = WTAP_ENCAP_LAPB;
241 pseudo_header->x25.flags = (direction & 1) ? 0 : 0x80;
244 case EYESDN_ENCAP_ATM: { /* ATM cells */
246 unsigned char cell[CELL_LEN];
249 if(pkt_len != CELL_LEN) {
250 *err = WTAP_ERR_BAD_FILE;
251 *err_info = g_strdup_printf(
252 "eyesdn: ATM cell has a length != 53 (%u)",
257 cur_off = file_tell(fh);
258 if (esc_read(cell, CELL_LEN, fh) != CELL_LEN) {
259 *err = file_error(fh, err_info);
261 *err = WTAP_ERR_SHORT_READ;
264 if (file_seek(fh, cur_off, SEEK_SET, err) == -1)
266 phdr->pkt_encap = WTAP_ENCAP_ATM_PDUS_UNTRUNCATED;
267 pseudo_header->atm.flags=ATM_RAW_CELL;
268 pseudo_header->atm.aal=AAL_UNKNOWN;
269 pseudo_header->atm.type=TRAF_UMTS_FP;
270 pseudo_header->atm.subtype=TRAF_ST_UNKNOWN;
271 pseudo_header->atm.vpi=((cell[0]&0xf)<<4) + (cell[0]&0xf);
272 pseudo_header->atm.vci=((cell[0]&0xf)<<4) + cell[0]; /* from cell */
273 pseudo_header->atm.channel=direction & 1;
277 case EYESDN_ENCAP_MTP2: /* SS7 frames */
278 pseudo_header->mtp2.sent = direction & 1;
279 pseudo_header->mtp2.annex_a_used = MTP2_ANNEX_A_USED_UNKNOWN;
280 pseudo_header->mtp2.link_number = channel;
281 phdr->pkt_encap = WTAP_ENCAP_MTP2_WITH_PHDR;
284 case EYESDN_ENCAP_DPNSS: /* DPNSS */
285 pseudo_header->isdn.uton = direction & 1;
286 pseudo_header->isdn.channel = channel;
287 phdr->pkt_encap = WTAP_ENCAP_DPNSS;
290 case EYESDN_ENCAP_DASS2: /* DASS2 frames */
291 pseudo_header->isdn.uton = direction & 1;
292 pseudo_header->isdn.channel = channel;
293 phdr->pkt_encap = WTAP_ENCAP_DPNSS;
296 case EYESDN_ENCAP_BACNET: /* BACNET async over HDLC frames */
297 pseudo_header->isdn.uton = direction & 1;
298 pseudo_header->isdn.channel = channel;
299 phdr->pkt_encap = WTAP_ENCAP_BACNET_MS_TP_WITH_PHDR;
302 case EYESDN_ENCAP_V5_EF: /* V5EF */
303 pseudo_header->isdn.uton = direction & 1;
304 pseudo_header->isdn.channel = channel;
305 phdr->pkt_encap = WTAP_ENCAP_V5_EF;
309 if(pkt_len > EYESDN_MAX_PACKET_LEN) {
310 *err = WTAP_ERR_BAD_FILE;
311 *err_info = g_strdup_printf("eyesdn: File has %u-byte packet, bigger than maximum of %u",
312 pkt_len, EYESDN_MAX_PACKET_LEN);
316 phdr->presence_flags = WTAP_HAS_TS;
317 phdr->ts.secs = secs;
318 phdr->ts.nsecs = usecs * 1000;
319 phdr->caplen = pkt_len;
322 /* Make sure we have enough room for the packet */
323 buffer_assure_space(buf, EYESDN_MAX_PACKET_LEN);
325 errno = WTAP_ERR_CANT_READ;
326 pd = buffer_start_ptr(buf);
327 bytes_read = esc_read(pd, pkt_len, fh);
328 if (bytes_read != pkt_len) {
329 if (bytes_read == -2) {
330 *err = file_error(fh, err_info);
332 *err = WTAP_ERR_SHORT_READ;
333 } else if (bytes_read == -1) {
334 *err = WTAP_ERR_BAD_FILE;
335 *err_info = g_strdup("eyesdn: No flag character seen in frame");
337 *err = WTAP_ERR_SHORT_READ;
345 esc_write(wtap_dumper *wdh, const guint8 *buf, int len, int *err)
349 static const guint8 esc = 0xfe;
351 for(i=0; i<len; i++) {
353 if(byte == 0xff || byte == 0xfe) {
355 * Escape the frame delimiter and escape byte.
357 if (!wtap_dump_file_write(wdh, &esc, sizeof esc, err))
361 if (!wtap_dump_file_write(wdh, &byte, sizeof byte, err))
367 static gboolean eyesdn_dump(wtap_dumper *wdh,
368 const struct wtap_pkthdr *phdr,
369 const guint8 *pd, int *err);
371 gboolean eyesdn_dump_open(wtap_dumper *wdh, int *err)
373 wdh->subtype_write=eyesdn_dump;
374 wdh->subtype_close=NULL;
376 if (!wtap_dump_file_write(wdh, eyesdn_hdr_magic,
377 EYESDN_HDR_MAGIC_SIZE, err))
379 wdh->bytes_dumped += EYESDN_HDR_MAGIC_SIZE;
384 int eyesdn_dump_can_write_encap(int encap)
387 case WTAP_ENCAP_ISDN:
388 case WTAP_ENCAP_LAYER1_EVENT:
389 case WTAP_ENCAP_DPNSS:
390 case WTAP_ENCAP_ATM_PDUS_UNTRUNCATED:
391 case WTAP_ENCAP_LAPB:
392 case WTAP_ENCAP_MTP2_WITH_PHDR:
393 case WTAP_ENCAP_BACNET_MS_TP_WITH_PHDR:
394 case WTAP_ENCAP_PER_PACKET:
398 return WTAP_ERR_UNSUPPORTED_ENCAP;
402 /* Write a record for a packet to a dump file.
403 * Returns TRUE on success, FALSE on failure. */
404 static gboolean eyesdn_dump(wtap_dumper *wdh,
405 const struct wtap_pkthdr *phdr,
406 const guint8 *pd, int *err)
408 static const guint8 start_flag = 0xff;
409 const union wtap_pseudo_header *pseudo_header = &phdr->pseudo_header;
410 guint8 buf[EYESDN_HDR_LENGTH];
418 /* Don't write out anything bigger than we can read.
419 * (The length field in packet headers is 16 bits, which
420 * imposes a hard limit.) */
421 if (phdr->caplen > 65535) {
422 *err = WTAP_ERR_PACKET_TOO_LARGE;
426 usecs=phdr->ts.nsecs/1000;
429 origin = pseudo_header->isdn.uton;
430 channel = pseudo_header->isdn.channel;
432 switch(phdr->pkt_encap) {
434 case WTAP_ENCAP_ISDN:
435 protocol=EYESDN_ENCAP_ISDN; /* set depending on decoder format and mode */
438 case WTAP_ENCAP_LAYER1_EVENT:
439 protocol=EYESDN_ENCAP_MSG;
442 case WTAP_ENCAP_DPNSS:
443 protocol=EYESDN_ENCAP_DPNSS;
447 case WTAP_ENCAP_DASS2:
448 protocol=EYESDN_ENCAP_DASS2;
452 case WTAP_ENCAP_ATM_PDUS_UNTRUNCATED:
453 protocol=EYESDN_ENCAP_ATM;
457 case WTAP_ENCAP_LAPB:
458 protocol=EYESDN_ENCAP_LAPB;
461 case WTAP_ENCAP_MTP2_WITH_PHDR:
462 protocol=EYESDN_ENCAP_MTP2;
465 case WTAP_ENCAP_BACNET_MS_TP_WITH_PHDR:
466 protocol=EYESDN_ENCAP_BACNET;
469 case WTAP_ENCAP_V5_EF:
470 protocol=EYESDN_ENCAP_V5_EF;
474 *err=WTAP_ERR_UNSUPPORTED_ENCAP;
478 phton24(&buf[0], usecs);
481 buf[4] = (guint8)(0xff & (secs >> 24));
482 buf[5] = (guint8)(0xff & (secs >> 16));
483 buf[6] = (guint8)(0xff & (secs >> 8));
484 buf[7] = (guint8)(0xff & (secs >> 0));
486 buf[8] = (guint8) channel;
487 buf[9] = (guint8) (origin?1:0) + (protocol << 1);
488 phtons(&buf[10], size);
491 if (!wtap_dump_file_write(wdh, &start_flag, sizeof start_flag, err))
493 if (!esc_write(wdh, buf, 12, err))
495 if (!esc_write(wdh, pd, size, err))