Supply a pseudo-header for all 802.11 packets; add an "fcs_len" field to

it, similar to the Ethernet pseudo-header's "fcs_len" field, and use it
in the 802.11 dissector.

svn path=/trunk/; revision=9884

5 files changed, 67 insertions, 49 deletions

diff --git a/wiretap/airopeek9.c b/wiretap/airopeek9.c
index 777628934a..4598d55ebd 100644
--- a/wiretap/airopeek9.c
+++ b/wiretap/airopeek9.c
@@ -1,7 +1,7 @@
 /* airopeek9.c
  * Routines for opening AiroPeek V9 files
  *
- * $Id: airopeek9.c,v 1.4 2004/01/25 21:55:12 guy Exp $
+ * $Id: airopeek9.c,v 1.5 2004/01/27 08:06:11 guy Exp $
  *
  * Wiretap Library
  * Copyright (c) 1998 by Gilbert Ramirez <gram@alumni.rice.edu>
@@ -74,6 +74,8 @@ static gboolean airopeek_read_v9(wtap *wth, int *err, gchar **err_info,
 static gboolean airopeek_seek_read_v9(wtap *wth, long seek_off,
     union wtap_pseudo_header *pseudo_header, guchar *pd, int length,
     int *err, gchar **err_info);
+static void airopeek_fill_pseudo_header(union wtap_pseudo_header *pseudo_header,
+    guchar *ap_pkt);
 
 static int wtap_file_read_pattern (wtap *wth, char *pattern, int *err)
 {
@@ -297,20 +299,7 @@ static gboolean airopeek_read_v9(wtap *wth, int *err, gchar **err_info _U_,
     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]);
+    airopeek_fill_pseudo_header(&wth->pseudo_header, ap_pkt);
 
     /* read the frame data */
     buffer_assure_space(wth->frame_buffer, sliceLength);
@@ -356,12 +345,7 @@ airopeek_seek_read_v9(wtap *wth, long seek_off,
     /* 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]);
+    airopeek_fill_pseudo_header(pseudo_header, ap_pkt);
 
     /*
      * XXX - should "errno" be set in "wtap_file_read_expected_bytes()"?
@@ -370,3 +354,24 @@ airopeek_seek_read_v9(wtap *wth, long seek_off,
     wtap_file_read_expected_bytes(pd, length, wth->random_fh, err);
     return TRUE;
 }
+
+/*
+ * 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.
+ */
+static void
+airopeek_fill_pseudo_header(union wtap_pseudo_header *pseudo_header,
+    guchar *ap_pkt)
+{
+    pseudo_header->ieee_802_11.fcs_len = 0;		/* no FCS */
+    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]);
+}
diff --git a/wiretap/etherpeek.c b/wiretap/etherpeek.c
index 9da771ae03..ab37b00051 100644
--- a/wiretap/etherpeek.c
+++ b/wiretap/etherpeek.c
@@ -2,7 +2,7 @@
  * Routines for opening EtherPeek (and TokenPeek?) files
  * Copyright (c) 2001, Daniel Thompson <d.thompson@gmx.net>
  *
- * $Id: etherpeek.c,v 1.26 2004/01/25 21:55:13 guy Exp $
+ * $Id: etherpeek.c,v 1.27 2004/01/27 08:06:11 guy Exp $
  *
  * Wiretap Library
  * Copyright (c) 1998 by Gilbert Ramirez <gram@alumni.rice.edu>
@@ -141,6 +141,8 @@ static gboolean etherpeek_read_v7(wtap *wth, int *err, gchar **err_info,
 static gboolean etherpeek_seek_read_v7(wtap *wth, long seek_off,
     union wtap_pseudo_header *pseudo_header, guchar *pd, int length,
     int *err, gchar **err_info);
+static void etherpeek_fill_pseudo_header_v7(
+    union wtap_pseudo_header *pseudo_header, airopeek_radio_hdr_t *radio_hdr);
 static gboolean etherpeek_read_v56(wtap *wth, int *err, gchar **err_info,
     long *data_offset);
 static gboolean etherpeek_seek_read_v56(wtap *wth, long seek_off,
@@ -418,9 +420,8 @@ static gboolean etherpeek_read_v7(wtap *wth, int *err, gchar **err_info,
 		wth->phdr.caplen -= 4;
 		wth->data_offset += 4;
 
-		wth->pseudo_header.ieee_802_11.channel = radio_hdr.channel;
-		wth->pseudo_header.ieee_802_11.data_rate = radio_hdr.data_rate;
-		wth->pseudo_header.ieee_802_11.signal_level = radio_hdr.signal_level;
+		etherpeek_fill_pseudo_header_v7(&wth->pseudo_header,
+		    &radio_hdr);
 		break;
 
 	case WTAP_ENCAP_ETHERNET:
@@ -497,9 +498,8 @@ etherpeek_seek_read_v7(wtap *wth, long seek_off,
 		wtap_file_read_expected_bytes(&radio_hdr, 4, wth->random_fh,
 		    err);
 
-		pseudo_header->ieee_802_11.channel = radio_hdr.channel;
-		pseudo_header->ieee_802_11.data_rate = radio_hdr.data_rate;
-		pseudo_header->ieee_802_11.signal_level = radio_hdr.signal_level;
+		etherpeek_fill_pseudo_header_v7(pseudo_header,
+		    &radio_hdr);
 		break;
 
 	case WTAP_ENCAP_ETHERNET:
@@ -518,6 +518,16 @@ etherpeek_seek_read_v7(wtap *wth, long seek_off,
 	return TRUE;
 }
 
+static void
+etherpeek_fill_pseudo_header_v7(union wtap_pseudo_header *pseudo_header,
+    airopeek_radio_hdr_t *radio_hdr)
+{
+	pseudo_header->ieee_802_11.fcs_len = 0;		/* no FCS */
+	pseudo_header->ieee_802_11.channel = radio_hdr->channel;
+	pseudo_header->ieee_802_11.data_rate = radio_hdr->data_rate;
+	pseudo_header->ieee_802_11.signal_level = radio_hdr->signal_level;
+}
+
 static gboolean etherpeek_read_v56(wtap *wth, int *err, gchar **err_info _U_,
     long *data_offset)
 {
diff --git a/wiretap/libpcap.c b/wiretap/libpcap.c
index 5dc5b02e97..2ae197c5a0 100644
--- a/wiretap/libpcap.c
+++ b/wiretap/libpcap.c
@@ -1,6 +1,6 @@
 /* libpcap.c
  *
- * $Id: libpcap.c,v 1.108 2004/01/25 21:55:15 guy Exp $
+ * $Id: libpcap.c,v 1.109 2004/01/27 08:06:12 guy Exp $
  *
  * Wiretap Library
  * Copyright (c) 1998 by Gilbert Ramirez <gram@alumni.rice.edu>
@@ -1045,6 +1045,15 @@ static gboolean libpcap_read(wtap *wth, int *err, gchar **err_info,
 		wth->pseudo_header.eth.fcs_len = -1;
 		break;
 
+	case WTAP_ENCAP_IEEE_802_11:
+		/*
+		 * We don't know whether there's an FCS in this frame or not.
+		 * XXX - are there any OSes where the capture mechanism
+		 * supplies an FCS?
+		 */
+		wth->pseudo_header.ieee_802_11.fcs_len = -1;
+		break;
+
 	case WTAP_ENCAP_IRDA:
 		if (packet_size < sizeof (struct irda_sll_hdr)) {
 			/*
diff --git a/wiretap/netxray.c b/wiretap/netxray.c
index 9d000a28fa..fe8068aa9e 100644
--- a/wiretap/netxray.c
+++ b/wiretap/netxray.c
@@ -1,6 +1,6 @@
 /* netxray.c
  *
- * $Id: netxray.c,v 1.88 2004/01/25 23:50:48 guy Exp $
+ * $Id: netxray.c,v 1.89 2004/01/27 08:06:12 guy Exp $
  *
  * Wiretap Library
  * Copyright (c) 1998 by Gilbert Ramirez <gram@alumni.rice.edu>
@@ -800,13 +800,6 @@ netxray_set_pseudo_header(wtap *wth, const guint8 *pd, int len,
 			break;
 
 		case WTAP_ENCAP_IEEE_802_11_WITH_RADIO:
-			pseudo_header->ieee_802_11.channel =
-			    hdr->hdr_2_x.xxx[12];
-			pseudo_header->ieee_802_11.data_rate =
-			    hdr->hdr_2_x.xxx[13];
-			pseudo_header->ieee_802_11.signal_level =
-			    hdr->hdr_2_x.xxx[14];
-
 			/*
 			 * It appears, in one 802.11 capture, that
 			 * we have 4 bytes of junk at the ends of
@@ -824,23 +817,22 @@ netxray_set_pseudo_header(wtap *wth, const guint8 *pd, int len,
 					/*
 					 * FCS.
 					 */
-#if 0
-					pseudo_header->eth.fcs_len = 4;
-#else
-					padding = 4;
-#endif
+					pseudo_header->ieee_802_11.fcs_len = 4;
 				} else {
 					/*
 					 * Junk.
 					 */
 					padding = 4;
 				}
-#if 0
 			} else
-				pseudo_header->eth.fcs_len = 0;
-#else
-			}
-#endif
+				pseudo_header->ieee_802_11.fcs_len = 0;
+
+			pseudo_header->ieee_802_11.channel =
+			    hdr->hdr_2_x.xxx[12];
+			pseudo_header->ieee_802_11.data_rate =
+			    hdr->hdr_2_x.xxx[13];
+			pseudo_header->ieee_802_11.signal_level =
+			    hdr->hdr_2_x.xxx[14];
 			break;
 
 		case WTAP_ENCAP_ISDN:
diff --git a/wiretap/wtap.h b/wiretap/wtap.h
index 9dfed9bf96..3ed84ae566 100644
--- a/wiretap/wtap.h
+++ b/wiretap/wtap.h
@@ -1,6 +1,6 @@
 /* wtap.h
  *
- * $Id: wtap.h,v 1.148 2004/01/25 21:55:17 guy Exp $
+ * $Id: wtap.h,v 1.149 2004/01/27 08:06:12 guy Exp $
  *
  * Wiretap Library
  * Copyright (c) 1998 by Gilbert Ramirez <gram@alumni.rice.edu>
@@ -330,8 +330,10 @@ struct p2p_phdr {
 	gboolean	sent; /* TRUE=sent, FALSE=received */
 };
 
-/* Packet "pseudo-header" information for 802.11 with radio information. */
+/* Packet "pseudo-header" information for 802.11
+   Radio information is only present for WTAP_ENCAP_IEEE_802_11_WITH_RADIO. */
 struct ieee_802_11_phdr {
+	gint	fcs_len;	/* Number of bytes of FCS - -1 means "unknown" */
 	guint8	channel;	/* Channel number */
 	guint8	data_rate;	/* in .5 Mb/s units */
 	guint8	signal_level;	/* percentage */