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-rw-r--r--wiretap/i4btrace.c336
1 files changed, 336 insertions, 0 deletions
diff --git a/wiretap/i4btrace.c b/wiretap/i4btrace.c
new file mode 100644
index 0000000..1b15972
--- /dev/null
+++ b/wiretap/i4btrace.c
@@ -0,0 +1,336 @@
+/* i4btrace.c
+ *
+ * Wiretap Library
+ * Copyright (c) 1999 by Bert Driehuis <driehuis@playbeing.org>
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#include "config.h"
+
+#include <stdlib.h>
+#include <string.h>
+#include "wtap-int.h"
+#include "file_wrappers.h"
+#include "i4b_trace.h"
+#include "i4btrace.h"
+
+typedef struct {
+ gboolean byte_swapped;
+} i4btrace_t;
+
+static gboolean i4btrace_read(wtap *wth, wtap_rec *rec, Buffer *buf,
+ int *err, gchar **err_info, gint64 *offset);
+static gboolean i4btrace_seek_read(wtap *wth, gint64 seek_off,
+ wtap_rec *rec, Buffer *buf, int *err, gchar **err_info);
+static int i4b_read_rec(wtap *wth, FILE_T fh, wtap_rec *rec,
+ Buffer *buf, int *err, gchar **err_info);
+
+static int i4btrace_file_type_subtype = -1;
+
+void register_i4btrace(void);
+
+/*
+ * Byte-swap the header.
+ */
+#define I4B_BYTESWAP_HEADER(hdr) \
+ { \
+ hdr.length = GUINT32_SWAP_LE_BE(hdr.length); \
+ hdr.unit = GUINT32_SWAP_LE_BE(hdr.unit); \
+ hdr.type = GUINT32_SWAP_LE_BE(hdr.type); \
+ hdr.dir = GUINT32_SWAP_LE_BE(hdr.dir); \
+ hdr.trunc = GUINT32_SWAP_LE_BE(hdr.trunc); \
+ hdr.count = GUINT32_SWAP_LE_BE(hdr.count); \
+ hdr.ts_sec = GUINT32_SWAP_LE_BE(hdr.ts_sec); \
+ hdr.ts_usec = GUINT32_SWAP_LE_BE(hdr.ts_usec); \
+ }
+
+/*
+ * Test some fields in the header to see if they make sense.
+ */
+#define I4B_HDR_IS_OK(hdr) \
+ (!(hdr.length < sizeof(hdr) || \
+ hdr.length > 16384 || \
+ hdr.unit > 4 || \
+ hdr.type > TRC_CH_B2 || \
+ hdr.dir > FROM_NT || \
+ hdr.trunc > 2048 || \
+ hdr.ts_usec >= 1000000))
+
+/*
+ * Number of packets to try reading.
+ */
+#define PACKETS_TO_CHECK 5
+
+wtap_open_return_val i4btrace_open(wtap *wth, int *err, gchar **err_info)
+{
+ i4b_trace_hdr_t hdr;
+ gboolean byte_swapped = FALSE;
+ i4btrace_t *i4btrace;
+
+ /* I4B trace files have no magic in the header... Sigh */
+ if (!wtap_read_bytes(wth->fh, &hdr, sizeof(hdr), err, err_info)) {
+ if (*err != WTAP_ERR_SHORT_READ)
+ return WTAP_OPEN_ERROR;
+ return WTAP_OPEN_NOT_MINE;
+ }
+
+ /* Silly heuristic... */
+ if (!I4B_HDR_IS_OK(hdr)) {
+ /*
+ * OK, try byte-swapping the header fields.
+ */
+ I4B_BYTESWAP_HEADER(hdr);
+ if (!I4B_HDR_IS_OK(hdr)) {
+ /*
+ * It doesn't look valid in either byte order.
+ */
+ return WTAP_OPEN_NOT_MINE;
+ }
+
+ /*
+ * It looks valid byte-swapped, so assume it's a
+ * trace written in the opposite byte order.
+ */
+ byte_swapped = TRUE;
+ }
+
+ /*
+ * Now try to read past the packet bytes; if that fails with
+ * a short read, we don't fail, so that we can report
+ * the file as a truncated I4B file.
+ */
+ if (!wtap_read_bytes(wth->fh, NULL, hdr.length - (guint32)sizeof(hdr),
+ err, err_info)) {
+ if (*err != WTAP_ERR_SHORT_READ)
+ return WTAP_OPEN_ERROR;
+ } else {
+ /*
+ * Now try reading a few more packets.
+ */
+ for (int i = 1; i < PACKETS_TO_CHECK; i++) {
+ /*
+ * Read and check the file header; we've already
+ * decided whether this would be a byte-swapped file
+ * or not, so we swap iff we decided it was.
+ */
+ if (!wtap_read_bytes_or_eof(wth->fh, &hdr, sizeof(hdr), err,
+ err_info)) {
+ if (*err == 0) {
+ /* EOF; no more packets to try. */
+ break;
+ }
+ if (*err != WTAP_ERR_SHORT_READ)
+ return WTAP_OPEN_ERROR;
+ return WTAP_OPEN_NOT_MINE;
+ }
+
+ if (byte_swapped)
+ I4B_BYTESWAP_HEADER(hdr);
+ if (!I4B_HDR_IS_OK(hdr)) {
+ /*
+ * It doesn't look valid.
+ */
+ return WTAP_OPEN_NOT_MINE;
+ }
+
+ /*
+ * Now try to read past the packet bytes; if that
+ * fails with a short read, we don't fail, so that
+ * we can report the file as a truncated I4B file.
+ */
+ if (!wtap_read_bytes(wth->fh, NULL,
+ hdr.length - (guint32)sizeof(hdr), err, err_info)) {
+ if (*err != WTAP_ERR_SHORT_READ)
+ return WTAP_OPEN_ERROR;
+
+ /*
+ * Probably a truncated file, so just quit.
+ */
+ break;
+ }
+ }
+ }
+
+ if (file_seek(wth->fh, 0, SEEK_SET, err) == -1)
+ return WTAP_OPEN_ERROR;
+
+ /* Get capture start time */
+
+ wth->file_type_subtype = i4btrace_file_type_subtype;
+ i4btrace = g_new(i4btrace_t, 1);
+ wth->priv = (void *)i4btrace;
+ wth->subtype_read = i4btrace_read;
+ wth->subtype_seek_read = i4btrace_seek_read;
+ wth->snapshot_length = 0; /* not known */
+
+ i4btrace->byte_swapped = byte_swapped;
+
+ wth->file_encap = WTAP_ENCAP_ISDN;
+ 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 i4btrace_read(wtap *wth, wtap_rec *rec, Buffer *buf,
+ int *err, gchar **err_info, gint64 *data_offset)
+{
+ *data_offset = file_tell(wth->fh);
+
+ return i4b_read_rec(wth, wth->fh, rec, buf, err, err_info);
+}
+
+static gboolean
+i4btrace_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 (!i4b_read_rec(wth, wth->random_fh, rec, buf, err, err_info)) {
+ /* Read error or EOF */
+ if (*err == 0) {
+ /* EOF means "short read" in random-access mode */
+ *err = WTAP_ERR_SHORT_READ;
+ }
+ return FALSE;
+ }
+ return TRUE;
+}
+
+static gboolean
+i4b_read_rec(wtap *wth, FILE_T fh, wtap_rec *rec, Buffer *buf,
+ int *err, gchar **err_info)
+{
+ i4btrace_t *i4btrace = (i4btrace_t *)wth->priv;
+ i4b_trace_hdr_t hdr;
+ guint32 length;
+
+ if (!wtap_read_bytes_or_eof(fh, &hdr, sizeof hdr, err, err_info))
+ return FALSE;
+
+ if (i4btrace->byte_swapped) {
+ /*
+ * Byte-swap the header.
+ */
+ I4B_BYTESWAP_HEADER(hdr);
+ }
+
+ if (hdr.length < sizeof(hdr)) {
+ *err = WTAP_ERR_BAD_FILE; /* record length < header! */
+ *err_info = ws_strdup_printf("i4btrace: record length %u < header length %lu",
+ hdr.length, (unsigned long)sizeof(hdr));
+ return FALSE;
+ }
+ length = hdr.length - (guint32)sizeof(hdr);
+ if (length > 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("i4btrace: File has %u-byte packet, bigger than maximum of %u",
+ length, 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->rec_header.packet_header.len = length;
+ rec->rec_header.packet_header.caplen = length;
+
+ rec->ts.secs = hdr.ts_sec;
+ rec->ts.nsecs = hdr.ts_usec * 1000;
+
+ switch (hdr.type) {
+
+ case TRC_CH_I:
+ /*
+ * XXX - what is it? It's probably not WTAP_ENCAP_NULL,
+ * as that means it has a 4-byte AF_ type as the
+ * encapsulation header.
+ */
+ rec->rec_header.packet_header.pkt_encap = WTAP_ENCAP_NULL;
+ break;
+
+ case TRC_CH_D:
+ /*
+ * D channel, so it's LAPD; set "p2p.sent".
+ */
+ rec->rec_header.packet_header.pkt_encap = WTAP_ENCAP_ISDN;
+ rec->rec_header.packet_header.pseudo_header.isdn.channel = 0;
+ break;
+
+ case TRC_CH_B1:
+ /*
+ * B channel 1.
+ */
+ rec->rec_header.packet_header.pkt_encap = WTAP_ENCAP_ISDN;
+ rec->rec_header.packet_header.pseudo_header.isdn.channel = 1;
+ break;
+
+ case TRC_CH_B2:
+ /*
+ * B channel 2.
+ */
+ rec->rec_header.packet_header.pkt_encap = WTAP_ENCAP_ISDN;
+ rec->rec_header.packet_header.pseudo_header.isdn.channel = 2;
+ break;
+ }
+
+ rec->rec_header.packet_header.pseudo_header.isdn.uton = (hdr.dir == FROM_TE);
+
+ /*
+ * Read the packet data.
+ */
+ return wtap_read_packet_bytes(fh, buf, length, err, err_info);
+}
+
+static const struct supported_block_type i4btrace_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 i4btrace_info = {
+ "I4B ISDN trace", "i4btrace", NULL, NULL,
+ FALSE, BLOCKS_SUPPORTED(i4btrace_blocks_supported),
+ NULL, NULL, NULL
+};
+
+void register_i4btrace(void)
+{
+ i4btrace_file_type_subtype = wtap_register_file_type_subtype(&i4btrace_info);
+
+ /*
+ * Register name for backwards compatibility with the
+ * wtap_filetypes table in Lua.
+ */
+ wtap_register_backwards_compatibility_lua_name("I4BTRACE",
+ i4btrace_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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