Check for all four types of IPX frame on DLT_LINUX_SLL captures.

diff --git a/gencode.c b/gencode.c
index 45afbc5abc1257b9339af2d1e704c94e157fe023..65d18ec9a2928d022ad01c63df240e807c34ec02 100644 (file)
--- a/gencode.c
+++ b/gencode.c
@@ -21,7 +21,7 @@
  */
 #ifndef lint
 static const char rcsid[] =
-    "@(#) $Header: /tcpdump/master/libpcap/gencode.c,v 1.145 2001-01-14 21:26:52 guy Exp $ (LBL)";
+    "@(#) $Header: /tcpdump/master/libpcap/gencode.c,v 1.146 2001-01-15 00:03:40 guy Exp $ (LBL)";
 #endif
 
 #ifdef HAVE_CONFIG_H
@@ -952,15 +952,36 @@ gen_linktype(proto)
 
                case LLCSAP_IPX:
                        /*
-                        * Check both for 802.2 frames with the IPX LSAP as
-                        * the DSAP and for Netware 802.3 frames.
+                        *      Ethernet_II frames, which are Ethernet
+                        *      frames with a frame type of ETHERTYPE_IPX;
+                        *
+                        *      Ethernet_802.3 frames, which have a frame
+                        *      type of LINUX_SLL_P_802_3;
+                        *
+                        *      Ethernet_802.2 frames, which are 802.3
+                        *      frames with an 802.2 LLC header (i.e, have
+                        *      a frame type of LINUX_SLL_P_802_2) and
+                        *      with the IPX LSAP as the DSAP in the LLC
+                        *      header;
+                        *
+                        *      Ethernet_SNAP frames, which are 802.3
+                        *      frames with an LLC header and a SNAP
+                        *      header and with an OUI of 0x000000
+                        *      (encapsulated Ethernet) and a protocol
+                        *      ID of ETHERTYPE_IPX in the SNAP header.
                         *
-                        * This generates code to check for 802.2 frames
-                        * with the IPX LSAP.
+                        * First, do the checks on LINUX_SLL_P_802_2
+                        * frames; generate the check for either
+                        * Ethernet_802.2 or Ethernet_SNAP frames, and
+                        * then put a check for LINUX_SLL_P_802_2 frames
+                        * before it.
                         */
-                       b0 = gen_cmp(off_linktype, BPF_H, LINUX_SLL_P_802_2);
-                       b1 = gen_cmp(off_linktype + 2, BPF_B,
+                       b0 = gen_cmp(off_linktype + 2, BPF_B,
                            (bpf_int32)LLCSAP_IPX);
+                       b1 = gen_snap(0x000000, ETHERTYPE_IPX,
+                           off_linktype + 2);
+                       gen_or(b0, b1);
+                       b0 = gen_cmp(off_linktype, BPF_H, LINUX_SLL_P_802_2);
                        gen_and(b0, b1);
 
                        /*
@@ -969,6 +990,15 @@ gen_linktype(proto)
                         */
                        b0 = gen_cmp(off_linktype, BPF_H, LINUX_SLL_P_802_3);
                        gen_or(b0, b1);
+
+                       /*
+                        * Now add the check for Ethernet_II frames, and
+                        * do that before checking for the other frame
+                        * types.
+                        */
+                       b0 = gen_cmp(off_linktype, BPF_H,
+                           (bpf_int32)ETHERTYPE_IPX);
+                       gen_or(b0, b1);
                        return b1;
 
                case ETHERTYPE_ATALK: