diff options
Diffstat (limited to 'wiretap/eyesdn.c')
-rw-r--r-- | wiretap/eyesdn.c | 514 |
1 files changed, 514 insertions, 0 deletions
diff --git a/wiretap/eyesdn.c b/wiretap/eyesdn.c new file mode 100644 index 00000000..4d22d6b7 --- /dev/null +++ b/wiretap/eyesdn.c @@ -0,0 +1,514 @@ +/* eyesdn.c + * + * Wiretap Library + * Copyright (c) 1998 by Gilbert Ramirez <gram@alumni.rice.edu> + * + * SPDX-License-Identifier: GPL-2.0-or-later + */ + +#include "config.h" +#include "wtap-int.h" +#include "eyesdn.h" +#include "file_wrappers.h" + +#include <stdlib.h> +#include <string.h> + +static int eyesdn_file_type_subtype = -1; + +void register_eyesdn(void); + +/* This module reads the output of the EyeSDN USB S0/E1 ISDN probes + * They store HDLC frames of D and B channels in a binary format + * The fileformat is + * + * 1-6 Byte: EyeSDN - Magic + * 7-n Byte: Frames + * + * Each Frame starts with the 0xff Flag byte + * - Bytes 0-2: timestamp (usec in network byte order) + * - Bytes 3-7: timestamp (40bits sec since 1970 in network byte order) + * - Byte 8: channel (0 for D channel, 1-30 for B1-B30) + * - Byte 9: Sender Bit 0(0 NT, 1 TE), Protocol in Bits 7:1, see enum + * - Byte 10-11: frame size in bytes + * - Byte 12-n: Frame Payload + * + * All multibyte values are represented in network byte order + * The frame is terminated with a flag character (0xff) + * bytes 0xff within a frame are escaped using the 0xfe escape character + * the byte following the escape character is decremented by two: + * so 0xfe 0xfd is actually a 0xff + * Characters that need to be escaped are 0xff and 0xfe + */ + + +static gboolean esc_read(FILE_T fh, guint8 *buf, int len, int *err, gchar **err_info) +{ + int i; + int value; + + for(i=0; i<len; i++) { + value=file_getc(fh); + if(value==-1) { + /* EOF or error */ + *err=file_error(fh, err_info); + if(*err==0) + *err=WTAP_ERR_SHORT_READ; + return FALSE; + } + if(value==0xff) { + /* error !!, read into next frame */ + *err=WTAP_ERR_BAD_FILE; + *err_info=g_strdup("eyesdn: No flag character seen in frame"); + return FALSE; + } + if(value==0xfe) { + /* we need to escape */ + value=file_getc(fh); + if(value==-1) { + /* EOF or error */ + *err=file_error(fh, err_info); + if(*err==0) + *err=WTAP_ERR_SHORT_READ; + return FALSE; + } + value+=2; + } + buf[i]=value; + } + + return TRUE; +} + +/* Magic text to check for eyesdn-ness of file */ +static const unsigned char eyesdn_hdr_magic[] = +{ 'E', 'y', 'e', 'S', 'D', 'N'}; +#define EYESDN_HDR_MAGIC_SIZE sizeof(eyesdn_hdr_magic) + +/* Size of a record header */ +#define EYESDN_HDR_LENGTH 12 + +static gboolean eyesdn_read(wtap *wth, wtap_rec *rec, Buffer *buf, + int *err, gchar **err_info, gint64 *data_offset); +static gboolean eyesdn_seek_read(wtap *wth, gint64 seek_off, + wtap_rec *rec, Buffer *buf, int *err, gchar **err_info); +static int read_eyesdn_rec(FILE_T fh, wtap_rec *rec, Buffer* buf, + int *err, gchar **err_info); + +/* Seeks to the beginning of the next packet, and returns the + byte offset. Returns -1 on failure, and sets "*err" to the error + and "*err_info" to null or an additional error string. */ +static gint64 eyesdn_seek_next_packet(wtap *wth, int *err, gchar **err_info) +{ + int byte; + gint64 cur_off; + + while ((byte = file_getc(wth->fh)) != EOF) { + if (byte == 0xff) { + cur_off = file_tell(wth->fh); + if (cur_off == -1) { + /* Error. */ + *err = file_error(wth->fh, err_info); + return -1; + } + return cur_off; + } + } + /* EOF or error. */ + *err = file_error(wth->fh, err_info); + return -1; +} + +wtap_open_return_val eyesdn_open(wtap *wth, int *err, gchar **err_info) +{ + char magic[EYESDN_HDR_MAGIC_SIZE]; + + /* Look for eyesdn header */ + if (!wtap_read_bytes(wth->fh, &magic, sizeof magic, err, err_info)) { + if (*err != WTAP_ERR_SHORT_READ) + return WTAP_OPEN_ERROR; + return WTAP_OPEN_NOT_MINE; + } + if (memcmp(magic, eyesdn_hdr_magic, EYESDN_HDR_MAGIC_SIZE) != 0) + return WTAP_OPEN_NOT_MINE; + + wth->file_encap = WTAP_ENCAP_PER_PACKET; + wth->file_type_subtype = eyesdn_file_type_subtype; + wth->snapshot_length = 0; /* not known */ + wth->subtype_read = eyesdn_read; + wth->subtype_seek_read = eyesdn_seek_read; + wth->file_tsprec = WTAP_TSPREC_USEC; + + return WTAP_OPEN_MINE; +} + +/* Find the next record and parse it; called from wtap_read(). */ +static gboolean eyesdn_read(wtap *wth, wtap_rec *rec, Buffer *buf, + int *err, gchar **err_info, gint64 *data_offset) +{ + gint64 offset; + + /* Find the next record */ + offset = eyesdn_seek_next_packet(wth, err, err_info); + if (offset < 1) + return FALSE; + *data_offset = offset; + + /* Parse the record */ + return read_eyesdn_rec(wth->fh, rec, buf, err, err_info); +} + +/* Used to read packets in random-access fashion */ +static gboolean +eyesdn_seek_read(wtap *wth, gint64 seek_off, wtap_rec *rec, + Buffer *buf, int *err, gchar **err_info) +{ + if (file_seek(wth->random_fh, seek_off, SEEK_SET, err) == -1) + return FALSE; + + return read_eyesdn_rec(wth->random_fh, rec, buf, err, err_info); +} + +/* Parses a record. */ +static gboolean +read_eyesdn_rec(FILE_T fh, wtap_rec *rec, Buffer *buf, int *err, + gchar **err_info) +{ + union wtap_pseudo_header *pseudo_header = &rec->rec_header.packet_header.pseudo_header; + guint8 hdr[EYESDN_HDR_LENGTH]; + time_t secs; + int usecs; + guint pkt_len; + guint8 channel, direction; + guint8 *pd; + + /* Our file pointer should be at the summary information header + * for a packet. Read in that header and extract the useful + * information. + */ + if (!esc_read(fh, hdr, EYESDN_HDR_LENGTH, err, err_info)) + return FALSE; + + /* extract information from header */ + usecs = pntoh24(&hdr[0]); +#ifdef TV64BITS + secs = hdr[3]; +#else + secs = 0; +#endif + secs = (secs << 8) | hdr[4]; + secs = (secs << 8) | hdr[5]; + secs = (secs << 8) | hdr[6]; + secs = (secs << 8) | hdr[7]; + + channel = hdr[8]; + direction = hdr[9]; + pkt_len = pntoh16(&hdr[10]); + + switch(direction >> 1) { + + default: + case EYESDN_ENCAP_ISDN: /* ISDN */ + pseudo_header->isdn.uton = direction & 1; + pseudo_header->isdn.channel = channel; + if(channel) { /* bearer channels */ + rec->rec_header.packet_header.pkt_encap = WTAP_ENCAP_ISDN; /* recognises PPP */ + pseudo_header->isdn.uton=!pseudo_header->isdn.uton; /* bug */ + } else { /* D channel */ + rec->rec_header.packet_header.pkt_encap = WTAP_ENCAP_ISDN; + } + break; + + case EYESDN_ENCAP_MSG: /* Layer 1 message */ + rec->rec_header.packet_header.pkt_encap = WTAP_ENCAP_LAYER1_EVENT; + pseudo_header->l1event.uton = (direction & 1); + break; + + case EYESDN_ENCAP_LAPB: /* X.25 via LAPB */ + rec->rec_header.packet_header.pkt_encap = WTAP_ENCAP_LAPB; + pseudo_header->dte_dce.flags = (direction & 1) ? 0 : 0x80; + break; + + case EYESDN_ENCAP_ATM: { /* ATM cells */ +#define CELL_LEN 53 + unsigned char cell[CELL_LEN]; + gint64 cur_off; + + if(pkt_len != CELL_LEN) { + *err = WTAP_ERR_BAD_FILE; + *err_info = ws_strdup_printf( + "eyesdn: ATM cell has a length != 53 (%u)", + pkt_len); + return FALSE; + } + + cur_off = file_tell(fh); + if (!esc_read(fh, cell, CELL_LEN, err, err_info)) + return FALSE; + if (file_seek(fh, cur_off, SEEK_SET, err) == -1) + return FALSE; + rec->rec_header.packet_header.pkt_encap = WTAP_ENCAP_ATM_PDUS_UNTRUNCATED; + pseudo_header->atm.flags=ATM_RAW_CELL; + pseudo_header->atm.aal=AAL_UNKNOWN; + pseudo_header->atm.type=TRAF_UMTS_FP; + pseudo_header->atm.subtype=TRAF_ST_UNKNOWN; + pseudo_header->atm.vpi=((cell[0]&0xf)<<4) + (cell[0]&0xf); + pseudo_header->atm.vci=((cell[0]&0xf)<<4) + cell[0]; /* from cell */ + pseudo_header->atm.channel=direction & 1; + } + break; + + case EYESDN_ENCAP_MTP2: /* SS7 frames */ + pseudo_header->mtp2.sent = direction & 1; + pseudo_header->mtp2.annex_a_used = MTP2_ANNEX_A_USED_UNKNOWN; + pseudo_header->mtp2.link_number = channel; + rec->rec_header.packet_header.pkt_encap = WTAP_ENCAP_MTP2_WITH_PHDR; + break; + + case EYESDN_ENCAP_DPNSS: /* DPNSS */ + pseudo_header->isdn.uton = direction & 1; + pseudo_header->isdn.channel = channel; + rec->rec_header.packet_header.pkt_encap = WTAP_ENCAP_DPNSS; + break; + + case EYESDN_ENCAP_DASS2: /* DASS2 frames */ + pseudo_header->isdn.uton = direction & 1; + pseudo_header->isdn.channel = channel; + rec->rec_header.packet_header.pkt_encap = WTAP_ENCAP_DPNSS; + break; + + case EYESDN_ENCAP_BACNET: /* BACNET async over HDLC frames */ + pseudo_header->isdn.uton = direction & 1; + pseudo_header->isdn.channel = channel; + rec->rec_header.packet_header.pkt_encap = WTAP_ENCAP_BACNET_MS_TP_WITH_PHDR; + break; + + case EYESDN_ENCAP_V5_EF: /* V5EF */ + pseudo_header->isdn.uton = direction & 1; + pseudo_header->isdn.channel = channel; + rec->rec_header.packet_header.pkt_encap = WTAP_ENCAP_V5_EF; + break; + } + + if(pkt_len > WTAP_MAX_PACKET_SIZE_STANDARD) { + *err = WTAP_ERR_BAD_FILE; + *err_info = ws_strdup_printf("eyesdn: File has %u-byte packet, bigger than maximum of %u", + pkt_len, WTAP_MAX_PACKET_SIZE_STANDARD); + return FALSE; + } + + rec->rec_type = REC_TYPE_PACKET; + rec->block = wtap_block_create(WTAP_BLOCK_PACKET); + rec->presence_flags = WTAP_HAS_TS; + rec->ts.secs = secs; + rec->ts.nsecs = usecs * 1000; + rec->rec_header.packet_header.caplen = pkt_len; + rec->rec_header.packet_header.len = pkt_len; + + /* Make sure we have enough room for the packet */ + ws_buffer_assure_space(buf, pkt_len); + + pd = ws_buffer_start_ptr(buf); + if (!esc_read(fh, pd, pkt_len, err, err_info)) + return FALSE; + return TRUE; +} + + +static gboolean +esc_write(wtap_dumper *wdh, const guint8 *buf, int len, int *err) +{ + int i; + guint8 byte; + static const guint8 esc = 0xfe; + + for(i=0; i<len; i++) { + byte=buf[i]; + if(byte == 0xff || byte == 0xfe) { + /* + * Escape the frame delimiter and escape byte. + */ + if (!wtap_dump_file_write(wdh, &esc, sizeof esc, err)) + return FALSE; + byte-=2; + } + if (!wtap_dump_file_write(wdh, &byte, sizeof byte, err)) + return FALSE; + } + return TRUE; +} + +static gboolean eyesdn_dump(wtap_dumper *wdh, + const wtap_rec *rec, + const guint8 *pd, int *err, gchar **err_info); + +static gboolean eyesdn_dump_open(wtap_dumper *wdh, int *err, gchar **err_info _U_) +{ + wdh->subtype_write=eyesdn_dump; + + if (!wtap_dump_file_write(wdh, eyesdn_hdr_magic, + EYESDN_HDR_MAGIC_SIZE, err)) + return FALSE; + *err=0; + return TRUE; +} + +static int eyesdn_dump_can_write_encap(int encap) +{ + switch (encap) { + case WTAP_ENCAP_ISDN: + case WTAP_ENCAP_LAYER1_EVENT: + case WTAP_ENCAP_DPNSS: + case WTAP_ENCAP_ATM_PDUS_UNTRUNCATED: + case WTAP_ENCAP_LAPB: + case WTAP_ENCAP_MTP2_WITH_PHDR: + case WTAP_ENCAP_BACNET_MS_TP_WITH_PHDR: + case WTAP_ENCAP_PER_PACKET: + return 0; + + default: + return WTAP_ERR_UNWRITABLE_ENCAP; + } +} + +/* Write a record for a packet to a dump file. + * Returns TRUE on success, FALSE on failure. */ +static gboolean eyesdn_dump(wtap_dumper *wdh, + const wtap_rec *rec, + const guint8 *pd, int *err, gchar **err_info _U_) +{ + static const guint8 start_flag = 0xff; + const union wtap_pseudo_header *pseudo_header = &rec->rec_header.packet_header.pseudo_header; + guint8 buf[EYESDN_HDR_LENGTH]; + int usecs; + time_t secs; + int channel; + int origin; + int protocol; + int size; + + /* We can only write packet records. */ + if (rec->rec_type != REC_TYPE_PACKET) { + *err = WTAP_ERR_UNWRITABLE_REC_TYPE; + return FALSE; + } + + /* Don't write out anything bigger than we can read. + * (The length field in packet headers is 16 bits, which + * imposes a hard limit.) */ + if (rec->rec_header.packet_header.caplen > 65535) { + *err = WTAP_ERR_PACKET_TOO_LARGE; + return FALSE; + } + + usecs=rec->ts.nsecs/1000; + secs=rec->ts.secs; + size=rec->rec_header.packet_header.caplen; + origin = pseudo_header->isdn.uton; + channel = pseudo_header->isdn.channel; + + switch(rec->rec_header.packet_header.pkt_encap) { + + case WTAP_ENCAP_ISDN: + protocol=EYESDN_ENCAP_ISDN; /* set depending on decoder format and mode */ + break; + + case WTAP_ENCAP_LAYER1_EVENT: + protocol=EYESDN_ENCAP_MSG; + break; + + case WTAP_ENCAP_DPNSS: + protocol=EYESDN_ENCAP_DPNSS; + break; + +#if 0 + case WTAP_ENCAP_DASS2: + protocol=EYESDN_ENCAP_DASS2; + break; +#endif + + case WTAP_ENCAP_ATM_PDUS_UNTRUNCATED: + protocol=EYESDN_ENCAP_ATM; + channel=0x80; + break; + + case WTAP_ENCAP_LAPB: + protocol=EYESDN_ENCAP_LAPB; + break; + + case WTAP_ENCAP_MTP2_WITH_PHDR: + protocol=EYESDN_ENCAP_MTP2; + break; + + case WTAP_ENCAP_BACNET_MS_TP_WITH_PHDR: + protocol=EYESDN_ENCAP_BACNET; + break; + + case WTAP_ENCAP_V5_EF: + protocol=EYESDN_ENCAP_V5_EF; + break; + + default: + *err=WTAP_ERR_UNWRITABLE_ENCAP; + return FALSE; + } + + phton24(&buf[0], usecs); + + buf[3] = (guint8)0; + buf[4] = (guint8)(0xff & (secs >> 24)); + buf[5] = (guint8)(0xff & (secs >> 16)); + buf[6] = (guint8)(0xff & (secs >> 8)); + buf[7] = (guint8)(0xff & (secs >> 0)); + + buf[8] = (guint8) channel; + buf[9] = (guint8) (origin?1:0) + (protocol << 1); + phtons(&buf[10], size); + + /* start flag */ + if (!wtap_dump_file_write(wdh, &start_flag, sizeof start_flag, err)) + return FALSE; + if (!esc_write(wdh, buf, 12, err)) + return FALSE; + if (!esc_write(wdh, pd, size, err)) + return FALSE; + return TRUE; +} + +static const struct supported_block_type eyesdn_blocks_supported[] = { + /* + * We support packet blocks, with no comments or other options. + */ + { WTAP_BLOCK_PACKET, MULTIPLE_BLOCKS_SUPPORTED, NO_OPTIONS_SUPPORTED } +}; + +static const struct file_type_subtype_info eyesdn_info = { + "EyeSDN USB S0/E1 ISDN trace format", "eyesdn", "trc", NULL, + FALSE, BLOCKS_SUPPORTED(eyesdn_blocks_supported), + eyesdn_dump_can_write_encap, eyesdn_dump_open, NULL +}; + +void register_eyesdn(void) +{ + eyesdn_file_type_subtype = wtap_register_file_type_subtype(&eyesdn_info); + + /* + * Register name for backwards compatibility with the + * wtap_filetypes table in Lua. + */ + wtap_register_backwards_compatibility_lua_name("EYESDN", + eyesdn_file_type_subtype); +} + +/* + * Editor modelines - https://www.wireshark.org/tools/modelines.html + * + * Local variables: + * c-basic-offset: 8 + * tab-width: 8 + * indent-tabs-mode: t + * End: + * + * vi: set shiftwidth=8 tabstop=8 noexpandtab: + * :indentSize=8:tabSize=8:noTabs=false: + */ |