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-rw-r--r--wiretap/capsa.c490
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diff --git a/wiretap/capsa.c b/wiretap/capsa.c
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--- /dev/null
+++ b/wiretap/capsa.c
@@ -0,0 +1,490 @@
+/* capsa.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 <string.h>
+#include "wtap-int.h"
+#include "file_wrappers.h"
+#include "capsa.h"
+#include <wsutil/ws_assert.h>
+
+/*
+ * A file begins with a header containing:
+ *
+ * a 4-byte magic number, with 'c', 'p', 's', 'e';
+ *
+ * either a 2-byte little-endian "format indicator" (version number?),
+ * or a 1-byte major version number followed by a 1-byte minor version
+ * number, or a 1-byte "format indicator" followed by something else
+ * that's always been 0;
+ *
+ * a 2-byte 0xe8 0x03 (1000 - a data rate? megabits/second?)
+ *
+ * 4 bytes of 0x01 0x00 0x01 0x00;
+ *
+ * either a 4-byte little-endian file size followed by 0x00 0x00 0x00 0x00
+ * or an 8-byte little-endian file size;
+ *
+ * a 4-byte little-endian packet count (in dns_error_of_udp, it exceeds?)
+ *
+ * a 4-byte little-endian number?
+ *
+ * hex 2c 01 c8 00 00 00 da 36 00 00 00 00 00 00;
+ *
+ * the same 4-byte little-endian number as above (yes, misaligned);
+ *
+ * 0x01 or 0x03;
+ *
+ * a bunch of 0s, up to an offset of 0x36d6;
+ *
+ * more stuff.
+ *
+ * Following that is a sequence of { record offset block, up to 200 records }
+ * pairs.
+ *
+ * A record offset block has 1 byte with the value 0xfe, a sequence of
+ * up to 200 4-byte little-endian record offsets, and 4 or more bytes
+ * of unknown data, making the block 805 bytes long.
+ *
+ * The record offsets are offsets, from the beginning of the record offset
+ * block (i.e., from the 0xfe byte), of the records following the block.
+ */
+
+/* Magic number in Capsa files. */
+static const char capsa_magic[] = {
+ 'c', 'p', 's', 'e'
+};
+
+/*
+ * Before each group of 200 or fewer records there's a block of frame
+ * offsets, giving the offsets, from the beginning of that block minus
+ * one(1), of the next N records.
+ */
+#define N_RECORDS_PER_GROUP 200
+
+/* Capsa (format indicator 1) record header. */
+struct capsarec_hdr {
+ guint32 unknown1; /* low-order 32 bits of a number? */
+ guint32 unknown2; /* 0x00 0x00 0x00 0x00 */
+ guint32 timestamplo; /* low-order 32 bits of the time stamp, in microseconds since January 1, 1970, 00:00:00 UTC */
+ guint32 timestamphi; /* high-order 32 bits of the time stamp, in microseconds since January 1, 1970, 00:00:00 UTC */
+ guint16 rec_len; /* length of record */
+ guint16 incl_len; /* number of octets captured in file */
+ guint16 orig_len; /* actual length of packet */
+ guint16 unknown5; /* 0x00 0x00 */
+ guint8 count1; /* count1*4 bytes after unknown8 */
+ guint8 count2; /* count2*4 bytes after that */
+ guint16 unknown7; /* 0x01 0x10 */
+ guint32 unknown8; /* 0x00 0x00 0x00 0x00 or random numbers */
+};
+
+/* Packet Builder (format indicator 2) record header. */
+struct pbrec_hdr {
+ guint16 rec_len; /* length of record */
+ guint16 incl_len; /* number of octets captured in file */
+ guint16 orig_len; /* actual length of packet */
+ guint16 unknown1;
+ guint16 unknown2;
+ guint16 unknown3;
+ guint32 unknown4;
+ guint32 timestamplo; /* low-order 32 bits of the time stamp, in microseconds since January 1, 1970, 00:00:00 UTC */
+ guint32 timestamphi; /* high-order 32 bits of the time stamp, in microseconds since January 1, 1970, 00:00:00 UTC */
+ guint32 unknown5;
+ guint32 unknown6;
+};
+
+typedef struct {
+ guint16 format_indicator;
+ guint32 number_of_frames;
+ guint32 frame_count;
+ gint64 base_offset;
+ guint32 record_offsets[N_RECORDS_PER_GROUP];
+} capsa_t;
+
+static gboolean capsa_read(wtap *wth, wtap_rec *rec, Buffer *buf,
+ int *err, gchar **err_info, gint64 *data_offset);
+static gboolean capsa_seek_read(wtap *wth, gint64 seek_off,
+ wtap_rec *rec, Buffer *buf, int *err, gchar **err_info);
+static int capsa_read_packet(wtap *wth, FILE_T fh, wtap_rec *rec,
+ Buffer *buf, int *err, gchar **err_info);
+
+static int capsa_file_type_subtype = -1;
+static int packet_builder_file_type_subtype = -1;
+
+void register_capsa(void);
+
+wtap_open_return_val capsa_open(wtap *wth, int *err, gchar **err_info)
+{
+ char magic[sizeof capsa_magic];
+ guint16 format_indicator;
+ int file_type_subtype;
+ guint32 number_of_frames;
+ capsa_t *capsa;
+
+ /* Read in the string that should be at the start of a Capsa file */
+ 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, capsa_magic, sizeof capsa_magic) != 0) {
+ return WTAP_OPEN_NOT_MINE;
+ }
+
+ /* Read the mysterious "format indicator" */
+ if (!wtap_read_bytes(wth->fh, &format_indicator, sizeof format_indicator,
+ err, err_info))
+ return WTAP_OPEN_ERROR;
+ format_indicator = GUINT16_FROM_LE(format_indicator);
+
+ /*
+ * Make sure it's a format we support.
+ */
+ switch (format_indicator) {
+
+ case 1: /* Capsa */
+ file_type_subtype = capsa_file_type_subtype;
+ break;
+
+ case 2: /* Packet Builder */
+ file_type_subtype = packet_builder_file_type_subtype;
+ break;
+
+ default:
+ *err = WTAP_ERR_UNSUPPORTED;
+ *err_info = ws_strdup_printf("capsa: format indicator %u unsupported",
+ format_indicator);
+ return WTAP_OPEN_ERROR;
+ }
+
+ /*
+ * Link speed, in megabytes/second?
+ */
+ if (!wtap_read_bytes(wth->fh, NULL, 2, err, err_info))
+ return WTAP_OPEN_ERROR;
+
+ /*
+ * Flags of some sort? Four 1-byte numbers, two of which are 1
+ * and two of which are zero? Two 2-byte numbers or flag fields,
+ * both of which are 1?
+ */
+ if (!wtap_read_bytes(wth->fh, NULL, 4, err, err_info))
+ return WTAP_OPEN_ERROR;
+
+ /*
+ * File size, in bytes.
+ */
+ if (!wtap_read_bytes(wth->fh, NULL, 4, err, err_info))
+ return WTAP_OPEN_ERROR;
+
+ /*
+ * Zeroes? Or upper 4 bytes of file size?
+ */
+ if (!wtap_read_bytes(wth->fh, NULL, 4, err, err_info))
+ return WTAP_OPEN_ERROR;
+
+ /*
+ * Count of packets.
+ */
+ if (!wtap_read_bytes(wth->fh, &number_of_frames, sizeof number_of_frames,
+ err, err_info))
+ return WTAP_OPEN_ERROR;
+ number_of_frames = GUINT32_FROM_LE(number_of_frames);
+
+ /*
+ * Skip past what we think is file header.
+ */
+ if (!file_seek(wth->fh, 0x44ef, SEEK_SET, err))
+ return WTAP_OPEN_ERROR;
+
+ wth->file_type_subtype = file_type_subtype;
+ capsa = g_new(capsa_t, 1);
+ capsa->format_indicator = format_indicator;
+ capsa->number_of_frames = number_of_frames;
+ capsa->frame_count = 0;
+ wth->priv = (void *)capsa;
+ wth->subtype_read = capsa_read;
+ wth->subtype_seek_read = capsa_seek_read;
+ /*
+ * XXX - we've never seen a Wi-Fi Capsa capture, so we don't
+ * yet know how to handle them.
+ */
+ wth->file_encap = WTAP_ENCAP_ETHERNET;
+ wth->snapshot_length = 0; /* not available in header */
+ wth->file_tsprec = WTAP_TSPREC_USEC;
+
+ /*
+ * Add an IDB; we don't know how many interfaces were
+ * involved, so we just say one interface, about which
+ * we only know the link-layer type, snapshot length,
+ * and time stamp resolution.
+ */
+ wtap_add_generated_idb(wth);
+
+ return WTAP_OPEN_MINE;
+}
+
+/* Read the next packet */
+static gboolean capsa_read(wtap *wth, wtap_rec *rec, Buffer *buf,
+ int *err, gchar **err_info, gint64 *data_offset)
+{
+ capsa_t *capsa = (capsa_t *)wth->priv;
+ guint32 frame_within_block;
+ int padbytes;
+
+ if (capsa->frame_count == capsa->number_of_frames) {
+ /*
+ * No more frames left. Return an EOF.
+ */
+ *err = 0;
+ return FALSE;
+ }
+ frame_within_block = capsa->frame_count % N_RECORDS_PER_GROUP;
+ if (frame_within_block == 0) {
+ /*
+ * Here's a record offset block.
+ * Get the offset of the block, and then skip the
+ * first byte.
+ */
+ capsa->base_offset = file_tell(wth->fh);
+ if (!wtap_read_bytes(wth->fh, NULL, 1, err, err_info))
+ return FALSE;
+
+ /*
+ * Now read the record offsets.
+ */
+ if (!wtap_read_bytes(wth->fh, &capsa->record_offsets,
+ sizeof capsa->record_offsets, err, err_info))
+ return FALSE;
+
+ /*
+ * And finish processing all 805 bytes by skipping
+ * the last 4 bytes.
+ */
+ if (!wtap_read_bytes(wth->fh, NULL, 4, err, err_info))
+ return FALSE;
+ }
+
+ *data_offset = capsa->base_offset +
+ GUINT32_FROM_LE(capsa->record_offsets[frame_within_block]);
+ if (!file_seek(wth->fh, *data_offset, SEEK_SET, err))
+ return FALSE;
+
+ padbytes = capsa_read_packet(wth, wth->fh, rec, buf, err, err_info);
+ if (padbytes == -1)
+ return FALSE;
+
+ /*
+ * Skip over the padding, if any.
+ */
+ if (padbytes != 0) {
+ if (!wtap_read_bytes(wth->fh, NULL, padbytes, err, err_info))
+ return FALSE;
+ }
+
+ capsa->frame_count++;
+
+ return TRUE;
+}
+
+static gboolean
+capsa_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;
+
+ if (capsa_read_packet(wth, wth->random_fh, rec, buf, err, err_info) == -1) {
+ if (*err == 0)
+ *err = WTAP_ERR_SHORT_READ;
+ return FALSE;
+ }
+ return TRUE;
+}
+
+static int
+capsa_read_packet(wtap *wth, FILE_T fh, wtap_rec *rec,
+ Buffer *buf, int *err, gchar **err_info)
+{
+ capsa_t *capsa = (capsa_t *)wth->priv;
+ struct capsarec_hdr capsarec_hdr;
+ struct pbrec_hdr pbrec_hdr;
+ guint32 rec_size;
+ guint32 packet_size;
+ guint32 orig_size;
+ guint32 header_size;
+ guint64 timestamp;
+
+ /* Read record header. */
+ switch (capsa->format_indicator) {
+
+ case 1:
+ if (!wtap_read_bytes_or_eof(fh, &capsarec_hdr,
+ sizeof capsarec_hdr, err, err_info))
+ return -1;
+ rec_size = GUINT16_FROM_LE(capsarec_hdr.rec_len);
+ orig_size = GUINT16_FROM_LE(capsarec_hdr.orig_len);
+ packet_size = GUINT16_FROM_LE(capsarec_hdr.incl_len);
+ header_size = sizeof capsarec_hdr;
+ timestamp = (((guint64)GUINT32_FROM_LE(capsarec_hdr.timestamphi))<<32) + GUINT32_FROM_LE(capsarec_hdr.timestamplo);
+
+ /*
+ * OK, the rest of this is variable-length.
+ * We skip: (count1+count2)*4 bytes.
+ * XXX - what is that? Measured statistics?
+ * Calculated statistics?
+ */
+ if (!wtap_read_bytes(fh, NULL,
+ (capsarec_hdr.count1 + capsarec_hdr.count2)*4,
+ err, err_info))
+ return -1;
+ header_size += (capsarec_hdr.count1 + capsarec_hdr.count2)*4;
+ break;
+
+ case 2:
+ if (!wtap_read_bytes_or_eof(fh, &pbrec_hdr,
+ sizeof pbrec_hdr, err, err_info))
+ return -1;
+ rec_size = GUINT16_FROM_LE(pbrec_hdr.rec_len);
+ orig_size = GUINT16_FROM_LE(pbrec_hdr.orig_len);
+ packet_size = GUINT16_FROM_LE(pbrec_hdr.incl_len);
+ header_size = sizeof pbrec_hdr;
+ timestamp = (((guint64)GUINT32_FROM_LE(pbrec_hdr.timestamphi))<<32) + GUINT32_FROM_LE(pbrec_hdr.timestamplo);
+ /*
+ * XXX - from the results of some conversions between
+ * Capsa format and pcap by Colasoft Packet Builder,
+ * I do not trust its conversion of time stamps (at
+ * least one of Colasoft's sample files, when
+ * converted to pcap format, has, as its time stamps,
+ * time stamps on the day after the conversion was
+ * done, which seems like more than just coincidence).
+ */
+ break;
+
+ default:
+ ws_assert_not_reached();
+ *err = WTAP_ERR_INTERNAL;
+ *err_info = ws_strdup_printf("capsa: format indicator is %u", capsa->format_indicator);
+ return -1;
+ }
+ if (orig_size > WTAP_MAX_PACKET_SIZE_STANDARD) {
+ /*
+ * Probably a corrupt capture file; don't blow up trying
+ * to allocate space for an immensely-large packet.
+ */
+ *err = WTAP_ERR_BAD_FILE;
+ *err_info = ws_strdup_printf("capsa: File has %u-byte original length, bigger than maximum of %u",
+ orig_size, WTAP_MAX_PACKET_SIZE_STANDARD);
+ return -1;
+ }
+ if (packet_size > WTAP_MAX_PACKET_SIZE_STANDARD) {
+ /*
+ * Probably a corrupt capture file; don't blow up trying
+ * to allocate space for an immensely-large packet.
+ */
+ *err = WTAP_ERR_BAD_FILE;
+ *err_info = ws_strdup_printf("capsa: File has %u-byte packet, bigger than maximum of %u",
+ packet_size, WTAP_MAX_PACKET_SIZE_STANDARD);
+ return -1;
+ }
+ if (header_size + packet_size > rec_size) {
+ /*
+ * Probably a corrupt capture file.
+ */
+ *err = WTAP_ERR_BAD_FILE;
+ *err_info = ws_strdup_printf("capsa: File has %u-byte packet with %u-byte record header, bigger than record size %u",
+ packet_size, header_size, rec_size);
+ return -1;
+ }
+
+ /*
+ * The "on the wire" record size always includes the CRC.
+ * If it's greater than the "captured" size by 4, then
+ * we subtract 4 from it, to reflect the way the "on the wire"
+ * record size works for other file formats.
+ */
+ if (orig_size == packet_size + 4)
+ orig_size = packet_size;
+
+ /*
+ * We assume there's no FCS in this frame.
+ * XXX - is there ever one?
+ */
+ rec->rec_header.packet_header.pseudo_header.eth.fcs_len = 0;
+
+ rec->rec_type = REC_TYPE_PACKET;
+ rec->block = wtap_block_create(WTAP_BLOCK_PACKET);
+ rec->rec_header.packet_header.caplen = packet_size;
+ rec->rec_header.packet_header.len = orig_size;
+ rec->presence_flags = WTAP_HAS_CAP_LEN|WTAP_HAS_TS;
+ rec->ts.secs = (time_t)(timestamp / 1000000);
+ rec->ts.nsecs = ((int)(timestamp % 1000000))*1000;
+
+ /*
+ * Read the packet data.
+ */
+ if (!wtap_read_packet_bytes(fh, buf, packet_size, err, err_info))
+ return -1; /* failed */
+
+ return rec_size - (header_size + packet_size);
+}
+
+static const struct supported_block_type capsa_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 capsa_info = {
+ "Colasoft Capsa format", "capsa", "cscpkt", NULL,
+ FALSE, BLOCKS_SUPPORTED(capsa_blocks_supported),
+ NULL, NULL, NULL
+};
+
+static const struct supported_block_type packet_builder_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 packet_builder_info = {
+ "Colasoft Packet Builder format", "colasoft-pb", "cscpkt", NULL,
+ FALSE, BLOCKS_SUPPORTED(packet_builder_blocks_supported),
+ NULL, NULL, NULL
+};
+
+void register_capsa(void)
+{
+ capsa_file_type_subtype = wtap_register_file_type_subtype(&capsa_info);
+ packet_builder_file_type_subtype = wtap_register_file_type_subtype(&packet_builder_info);
+
+ /*
+ * Register names for backwards compatibility with the
+ * wtap_filetypes table in Lua.
+ */
+ wtap_register_backwards_compatibility_lua_name("COLASOFT_CAPSA",
+ capsa_file_type_subtype);
+ wtap_register_backwards_compatibility_lua_name("COLASOFT_PACKET_BUILDER",
+ packet_builder_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:
+ */
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