From Martijn Schipper: support for reading AiroPeek files in V9 capture

file format (AiroPeek 2.x).

svn path=/trunk/; revision=9144

1 files changed, 278 insertions, 0 deletions

diff --git a/wiretap/airopeek9.c b/wiretap/airopeek9.c
new file mode 100644
index 0000000000..7cf2be3523
--- /dev/null
+++ b/wiretap/airopeek9.c
@@ -0,0 +1,278 @@
+/* airopeek9.c
+ * Routines for opening AiroPeek V9 files
+ *
+ * $Id: airopeek9.c,v 1.1 2003/12/02 19:37:05 guy Exp $
+ *
+ * Wiretap Library
+ * Copyright (c) 1998 by Gilbert Ramirez <gram@alumni.rice.edu>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+#include <errno.h>
+#include <string.h>
+#include <stdlib.h>
+#include "wtap-int.h"
+#include "file_wrappers.h"
+#include "buffer.h"
+#include "airopeek9.h"
+
+/* CREDITS
+ *
+ * This file decoder could not have been writen without examining
+ * http://www.varsanofiev.com/inside/airopeekv9.htm, the help from
+ * Martin Regner and Guy Harris, and the etherpeek.c file.
+ */
+
+/* section header */
+typedef struct airopeek_section_header {
+	gint8   section_id[4];
+	guint32 section_len;
+	guint32 section_const;
+} airopeek_section_header_t;
+
+#define AIROPEEK_V9_LENGTH_OFFSET		2
+#define AIROPEEK_V9_TIMESTAMP_LOWER_OFFSET	8
+#define AIROPEEK_V9_TIMESTAMP_UPPER_OFFSET	14
+#define AIROPEEK_V9_FLAGS_OFFSET		20
+#define AIROPEEK_V9_STATUS_OFFSET		22
+#define AIROPEEK_V9_CHANNEL_OFFSET		26
+#define AIROPEEK_V9_RATE_OFFSET			32
+#define AIROPEEK_V9_SIGNAL_PERC_OFFSET		38
+#define AIROPEEK_V9_SIGNAL_DBM_OFFSET		44
+#define AIROPEEK_V9_NOISE_PERC_OFFSET		50
+#define AIROPEEK_V9_NOISE_DBM_OFFSET		56
+#define AIROPEEK_V9_SLICE_LENGTH_OFFSET		62
+
+#define AIROPEEK_V9_PKT_SIZE			66
+
+/* 64-bit time in nano seconds from the (Mac) epoch */
+typedef struct airopeek_utime {
+	guint32 upper;
+	guint32 lower;
+} airopeek_utime;
+
+static const unsigned int mac2unix = 2082844800u;
+
+static gboolean airopeek_read_v9(wtap *wth, int *err, long *data_offset);
+static gboolean airopeek_seek_read_v9(wtap *wth, long seek_off,
+    union wtap_pseudo_header *pseudo_header, guchar *pd, int length, int *err);
+
+static int wtap_file_read_pattern (wtap *wth, char *pattern, int *err)
+{
+    char c;
+    char *cp;
+
+    cp = pattern;
+    while (*cp)
+    {
+	wtap_file_read_unknown_bytes(&c, 1, wth->fh, err);
+	if (c == *cp)
+	    cp++;
+	else
+	{
+	    if (c == pattern[0])
+		cp = &pattern[1];
+	    else
+		cp = pattern;
+	}
+    }
+    return (*cp == '\0' ? TRUE : FALSE);
+}
+
+
+static int wtap_file_read_till_separator (wtap *wth, char *buffer, int buflen,
+					char *separators, int *err)
+{
+    char c;
+    char *cp;
+    int i;
+
+    for (cp = buffer, i = 0; i < buflen; i++, cp++)
+    {
+	wtap_file_read_unknown_bytes(&c, 1, wth->fh, err);
+	if (strchr (separators, c))
+	{
+	    *cp = '\0';
+	    break;
+	}
+	else
+	    *cp = c;
+    }
+    return i;
+}
+
+
+static gboolean wtap_file_read_number (wtap *wth, guint32 *num, int *err)
+{
+    char str_num[12];
+    unsigned long long value;
+    char *p;
+
+    wtap_file_read_till_separator (wth, str_num, sizeof (str_num)-1, "<", err);
+    value = strtoul (str_num, &p, 10);
+    if (p == str_num || value > UINT_MAX)
+	return FALSE;
+    *num = value;
+    return TRUE;
+}
+
+
+int airopeek9_open(wtap *wth, int *err)
+{
+    airopeek_section_header_t ap_hdr;
+    guint32 fileVersion;
+    guint32 mediaType;
+    int file_encap;
+
+    wtap_file_read_unknown_bytes(&ap_hdr, sizeof(ap_hdr), wth->fh, err);
+
+    if (memcmp (ap_hdr.section_id, "\177ver", sizeof(ap_hdr.section_id)) ||
+	wtap_file_read_pattern (wth, "<FileVersion>", err) == FALSE ||
+	wtap_file_read_number (wth, &fileVersion, err) == FALSE ||
+	fileVersion != 9 ||
+	wtap_file_read_pattern (wth, "<MediaType>", err) == FALSE ||
+	wtap_file_read_number (wth, &mediaType, err) == FALSE)
+	return 0;
+
+    if (wtap_file_read_pattern (wth, "pkts", err) == FALSE)
+	return 0;
+
+    /* skip 8 zero bytes */
+    if (file_seek (wth->fh, 8L, SEEK_CUR, err) == -1)
+	return 0;
+
+    /*
+     * This is an AiroPeek V9 file.
+     */
+
+    wth->data_offset = file_tell (wth->fh);
+
+    file_encap = WTAP_ENCAP_IEEE_802_11_WITH_RADIO;
+
+    wth->file_type = WTAP_FILE_AIROPEEK_V9;
+    wth->file_encap = file_encap;
+    wth->subtype_read = airopeek_read_v9;
+    wth->subtype_seek_read = airopeek_seek_read_v9;
+
+    wth->snapshot_length   = 0; /* not available in header */
+
+    return 1;
+}
+
+static gboolean airopeek_read_v9(wtap *wth, int *err, long *data_offset)
+{
+    guchar ap_pkt[AIROPEEK_V9_PKT_SIZE];
+    guint32 length;
+    guint32 sliceLength;
+    airopeek_utime timestamp;
+    double  t;
+
+    *data_offset = wth->data_offset;
+
+    wtap_file_read_expected_bytes(ap_pkt, sizeof(ap_pkt), wth->fh, err);
+    wth->data_offset += sizeof(ap_pkt);
+
+    /* Extract the fields from the packet */
+    length = pletohl(&ap_pkt[AIROPEEK_V9_LENGTH_OFFSET]);
+    sliceLength = pletohl(&ap_pkt[AIROPEEK_V9_SLICE_LENGTH_OFFSET]);
+    timestamp.upper = pletohl(&ap_pkt[AIROPEEK_V9_TIMESTAMP_UPPER_OFFSET]);
+    timestamp.lower = pletohl(&ap_pkt[AIROPEEK_V9_TIMESTAMP_LOWER_OFFSET]);
+
+    /* force sliceLength to be the actual length of the packet */
+    if (sliceLength == 0) {
+	sliceLength = length;
+    }
+
+    /* fill in packet header length values before slicelength may be
+       adjusted */
+    wth->phdr.len    = length;
+    wth->phdr.caplen = sliceLength;
+
+    /*
+     * Fill the pseudo header with radio information.
+     * XXX - we should supply the additional information;
+     * the pseudo-header should probably be supplied in a fashion
+     * similar to the new BSD radio header, so that the 802.11
+     * dissector can determine which, if any, information items
+     * are present.
+     */
+    wth->pseudo_header.ieee_802_11.channel =
+	    pletohl(&ap_pkt[AIROPEEK_V9_CHANNEL_OFFSET]);
+    wth->pseudo_header.ieee_802_11.data_rate =
+	    pletohl(&ap_pkt[AIROPEEK_V9_RATE_OFFSET]);
+    wth->pseudo_header.ieee_802_11.signal_level =
+	    pletohl(&ap_pkt[AIROPEEK_V9_SIGNAL_PERC_OFFSET]);
+
+    /* read the frame data */
+    buffer_assure_space(wth->frame_buffer, sliceLength);
+    wtap_file_read_expected_bytes(buffer_start_ptr(wth->frame_buffer),
+				  sliceLength, wth->fh, err);
+    wth->data_offset += sliceLength;
+
+    /* recalculate and fill in packet time stamp */
+    t =  (double) timestamp.lower +
+	 (double) timestamp.upper * 4294967296.0;
+
+    t = t / 1000.0;	/* nano seconds -> micro seconds */
+    t -= (double) mac2unix * 1000000.0;
+    wth->phdr.ts.tv_sec  = (time_t)  (t/1000000.0);
+    wth->phdr.ts.tv_usec = (guint32) (t - (double) wth->phdr.ts.tv_sec *
+						   1000000.0);
+
+    /*
+     * The last 4 bytes sometimes contains the FCS but on a lot of
+     * interfaces these are zero. To eleminate problems we reduce
+     * the length by 4.
+     *
+     * XXX - is there any way to find out whether it's an FCS or not?
+     */
+    wth->phdr.len -= 4;
+    wth->phdr.caplen -= 4;
+
+    wth->phdr.pkt_encap = wth->file_encap;
+    return TRUE;
+}
+
+
+static gboolean
+airopeek_seek_read_v9(wtap *wth, long seek_off,
+    union wtap_pseudo_header *pseudo_header, guchar *pd, int length, int *err)
+{
+    guchar ap_pkt[AIROPEEK_V9_PKT_SIZE];
+
+    if (file_seek(wth->random_fh, seek_off, SEEK_SET, err) == -1)
+	return FALSE;
+
+    /* Read the packet header. */
+    wtap_file_read_expected_bytes(ap_pkt, sizeof(ap_pkt), wth->random_fh, err);
+
+    pseudo_header->ieee_802_11.channel =
+	    pletohl(&ap_pkt[AIROPEEK_V9_CHANNEL_OFFSET]);
+    pseudo_header->ieee_802_11.data_rate =
+	    pletohl(&ap_pkt[AIROPEEK_V9_RATE_OFFSET]);
+    pseudo_header->ieee_802_11.signal_level =
+	    pletohl(&ap_pkt[AIROPEEK_V9_SIGNAL_PERC_OFFSET]);
+
+    /*
+     * XXX - should "errno" be set in "wtap_file_read_expected_bytes()"?
+     */
+    errno = WTAP_ERR_CANT_READ;
+    wtap_file_read_expected_bytes(pd, length, wth->random_fh, err);
+    return TRUE;
+}