iFCP uses one dedicated TCP session per fc-endpoint pair.

The FC D_id and S_id fields in teh FC frame encapsulated inside iFCP unfortunately has "undefined" (semi-random) values    so we can not use th S_/D_id matching in FC when transported atop iFCP.


Change iFCP to call a new  fc_ifcp handler instead of the fc handler.

Add a new handler to FC specific to iFCP. 
Only set the pinfo->src/dst fields to the S_id/D_id fields IFF the FC frame was NOT transported ontop of iFCP.
Othervise  we just use the TCP/IP values that are already stored there.

Some Hosts use RelativeOffset fields for FC.  We can only dissect the RelOff field with offset 0.
Change FC to only call the FCP subdissector if offset==0  when relative offsets are used.


Some hosts when using relative offsets  do not specify a proper value for rxid in teh commands instead htey lkeave it as 0xffff
Change the FCP conversation matching to ignore RXID when searching for a conversation.



svn path=/trunk/; revision=15076

3 files changed, 44 insertions, 13 deletions

diff --git a/epan/dissectors/packet-fc.c b/epan/dissectors/packet-fc.c
index f6000c9fe7..efab45c62c 100644
--- a/epan/dissectors/packet-fc.c
+++ b/epan/dissectors/packet-fc.c
@@ -756,7 +756,7 @@ static const value_string fc_els_proto_val[] = {
 
 /* Code to actually dissect the packets */
 static void
-dissect_fc (tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
+dissect_fc_helper (tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, gboolean is_ifcp)
 {
    /* Set up structures needed to add the protocol subtree and manage it */
     proto_item *ti=NULL;
@@ -798,11 +798,24 @@ dissect_fc (tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
         offset += 8;
         fchdr.r_ctl = tvb_get_guint8 (tvb, offset);
     }
-    
-    SET_ADDRESS (&pinfo->dst, AT_FC, 3, tvb_get_ptr(tvb,offset+1,3));
-    SET_ADDRESS (&fchdr.d_id, AT_FC, 3, tvb_get_ptr(tvb,offset+1,3));
-    SET_ADDRESS (&pinfo->src, AT_FC, 3, tvb_get_ptr(tvb,offset+5,3));
-    SET_ADDRESS (&fchdr.s_id, AT_FC, 3, tvb_get_ptr(tvb,offset+5,3));
+
+    /* Each fc endpoint pair gets its own TCP session in iFCP but
+     * the src/dst ids are undefined(==semi-random) in the FC header.
+     * This means we can no track conversations for FC over iFCP by using
+     * the FC src/dst addresses.
+     * For iFCP: Do not update the pinfo src/dst struct and let it remain 
+     * being tcpip src/dst so that request/response matching in the FCP layer
+     * will use ip addresses instead and still work.
+     */
+    if(!is_ifcp){    
+	SET_ADDRESS (&pinfo->dst, AT_FC, 3, tvb_get_ptr(tvb,offset+1,3));
+	SET_ADDRESS (&pinfo->src, AT_FC, 3, tvb_get_ptr(tvb,offset+5,3));
+	pinfo->srcport=0;
+	pinfo->destport=0;
+    }
+    SET_ADDRESS (&fchdr.d_id, pinfo->dst.type, pinfo->dst.len, pinfo->dst.data);
+    SET_ADDRESS (&fchdr.s_id, pinfo->src.type, pinfo->src.len, pinfo->src.data);
+
     fchdr.cs_ctl = tvb_get_guint8 (tvb, offset+4);
     fchdr.type  = tvb_get_guint8 (tvb, offset+8);
     fchdr.fctl=tvb_get_ntoh24(tvb,offset+9);
@@ -836,7 +849,7 @@ dissect_fc (tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
     is_valid_frame = ((pinfo->sof_eof & 0x40) == 0x40);
 
     ftype = fc_get_ftype (fchdr.r_ctl, fchdr.type);
-    
+
     if (check_col (pinfo->cinfo, COL_INFO)) {
          col_add_str (pinfo->cinfo, COL_INFO, val_to_str (ftype, fc_ftype_vals,
                                                           "Unknown Type (0x%x)"));
@@ -1027,7 +1040,7 @@ dissect_fc (tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
                                     fchdr.r_ctl & 0x0F);
         break;
     }
-        
+  
     proto_tree_add_uint_hidden (fc_tree, hf_fc_ftype, tvb, offset, 1,
                            ftype); 
 
@@ -1267,9 +1280,15 @@ dissect_fc (tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
     }
 
     if ((ftype != FC_FTYPE_LINKCTL) && (ftype != FC_FTYPE_BLS)) {
-        if (!dissector_try_port (fcftype_dissector_table, ftype, next_tvb,
-                                 pinfo, tree)) {
+	/* If relative offset is used, only dissect the pdu with
+	 * offset 0 (param) */
+	if( (fchdr.fctl&FC_FCTL_REL_OFFSET) && param ){
             call_dissector (data_handle, next_tvb, pinfo, tree);
+	} else {
+	    if (!dissector_try_port (fcftype_dissector_table, ftype, 
+				next_tvb, pinfo, tree)) {
+	        call_dissector (data_handle, next_tvb, pinfo, tree);
+            }
         }
     } else if (ftype == FC_FTYPE_BLS) {
         if ((fchdr.r_ctl & 0x0F) == FC_BLS_BAACC) {
@@ -1282,6 +1301,16 @@ dissect_fc (tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
     tap_queue_packet(fc_tap, pinfo, &fchdr);
 }
 
+static void
+dissect_fc (tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
+{
+    dissect_fc_helper (tvb, pinfo, tree, FALSE);
+}
+static void
+dissect_fc_ifcp (tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
+{
+    dissect_fc_helper (tvb, pinfo, tree, TRUE);
+}
 
 /* Register the protocol with Ethereal */
 
@@ -1436,6 +1465,7 @@ proto_register_fc(void)
     /* Register the protocol name and description */
     proto_fc = proto_register_protocol ("Fibre Channel", "FC", "fc");
     register_dissector ("fc", dissect_fc, proto_fc);
+    register_dissector ("fc_ifcp", dissect_fc_ifcp, proto_fc);
     fc_tap = register_tap("fc");
 
     /* Required function calls to register the header fields and subtrees used */
diff --git a/epan/dissectors/packet-fcp.c b/epan/dissectors/packet-fcp.c
index 5b4f8b7fd1..247c55923c 100644
--- a/epan/dissectors/packet-fcp.c
+++ b/epan/dissectors/packet-fcp.c
@@ -263,6 +263,8 @@ dissect_fcp_cmnd (tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
                                       pinfo->ptype, pinfo->oxid,
                                       pinfo->rxid, NO_PORT2);
     if (!conversation) {
+	/* NO_PORT2: Dont check RXID, iFCP traces i have all have 
+	 * RXID==0xffff in the command PDU.   ronnie */
         conversation = conversation_new (pinfo->fd->num, &pinfo->src, &pinfo->dst,
                                          pinfo->ptype, pinfo->oxid,
                                          pinfo->rxid, NO_PORT2);
@@ -375,7 +377,7 @@ dissect_fcp_data (tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
     scsi_task_id_t task_key;
 
     /* Retrieve conversation state to determine expected payload */
-    conversation = find_conversation (pinfo->fd->num, &pinfo->src, &pinfo->dst,
+    conversation = find_conversation (pinfo->fd->num, &pinfo->dst, &pinfo->src,
                                       pinfo->ptype, pinfo->oxid,
                                       pinfo->rxid, NO_PORT2);
     if (conversation) {
diff --git a/epan/dissectors/packet-ifcp.c b/epan/dissectors/packet-ifcp.c
index 2e5faa02b1..363c833285 100755
--- a/epan/dissectors/packet-ifcp.c
+++ b/epan/dissectors/packet-ifcp.c
@@ -558,6 +558,5 @@ proto_reg_handoff_ifcp (void)
     dissector_add_handle("tcp.port", ifcp_handle);
 
     data_handle = find_dissector("data");
-    fc_handle = find_dissector("fc");
+    fc_handle = find_dissector("fc_ifcp");
 }
-