From daulis0@gmail.com:

There are 2 parts to the CIGI protocol. 1) Host to IG messages and 2) IG to
Host messages. Currently, Host to IG messages are parsed correctly, but IG to
Host messages show Malformed Packet (or may not even detect as CIGI at all)

Some of the protocol format is different between versions. The "Minor Version"
is used by the dissector to separate the differences, but this field is in a
different location in the IG Control Packet (Host to IG message) vs the Start
of Frame Packet (IG to Host message).

Attached patch to correct this.

svn path=/trunk/; revision=35241

1 files changed, 23 insertions, 3 deletions

diff --git a/epan/dissectors/packet-cigi.c b/epan/dissectors/packet-cigi.c
index ece83f9510..5e9ce814b9 100644
--- a/epan/dissectors/packet-cigi.c
+++ b/epan/dissectors/packet-cigi.c
@@ -912,6 +912,7 @@ static int hf_cigi3_2_ig_control = -1;
 static int hf_cigi3_2_ig_control_db_number = -1;
 static int hf_cigi3_2_ig_control_ig_mode = -1;
 static int hf_cigi3_2_ig_control_timestamp_valid = -1;
+static int hf_cigi3_2_ig_control_minor_version = -1;
 static int hf_cigi3_2_ig_control_host_frame_number = -1;
 static int hf_cigi3_2_ig_control_timestamp = -1;
 static int hf_cigi3_2_ig_control_last_ig_frame_number = -1;
@@ -2092,6 +2093,7 @@ static int hf_cigi3_2_start_of_frame_ig_status = -1;
 static int hf_cigi3_2_start_of_frame_ig_mode = -1;
 static int hf_cigi3_2_start_of_frame_timestamp_valid = -1;
 static int hf_cigi3_2_start_of_frame_earth_reference_model = -1;
+static int hf_cigi3_2_start_of_frame_minor_version = -1;
 static int hf_cigi3_2_start_of_frame_ig_frame_number = -1;
 static int hf_cigi3_2_start_of_frame_timestamp = -1;
 static int hf_cigi3_2_start_of_frame_last_host_frame_number = -1;
@@ -3010,9 +3012,15 @@ cigi3_add_tree(tvbuff_t *tvb, proto_tree *cigi_tree)
         /* If we have the start of frame or IG Control packet set the version */
         if ( ( packet_id == CIGI3_PACKET_ID_IG_CONTROL || packet_id == CIGI3_PACKET_ID_START_OF_FRAME ) && global_cigi_version == CIGI_VERSION_FROM_PACKET ) {
             cigi_version = tvb_get_guint8(tvb, 2);
-            if ( packet_size == CIGI3_2_PACKET_SIZE_IG_CONTROL || packet_size == CIGI3_2_PACKET_SIZE_START_OF_FRAME ) {
+
+            /* CIGI Minor Version first appeared in CIGI 3.2. Note: It is in a
+             * different location in IG Control vs Start of Frame. */
+            if ( packet_size == CIGI3_2_PACKET_SIZE_IG_CONTROL && packet_id == CIGI3_PACKET_ID_IG_CONTROL ) {
                cigi_minor_version = tvb_get_guint8(tvb, 4) >> 4;
+            } else if ( packet_size == CIGI3_2_PACKET_SIZE_START_OF_FRAME && packet_id == CIGI3_PACKET_ID_START_OF_FRAME ) {
+               cigi_minor_version = tvb_get_guint8(tvb, 5) >> 4;
             } else {
+               /* CIGI version prior to 3.2 */
                cigi_minor_version = 0;
             }
         }
@@ -4193,6 +4201,7 @@ cigi3_2_add_ig_control(tvbuff_t *tvb, proto_tree *tree, gint offset)
 
     proto_tree_add_item(tree, hf_cigi3_2_ig_control_ig_mode, tvb, offset, 1, cigi_byte_order);
     proto_tree_add_item(tree, hf_cigi3_2_ig_control_timestamp_valid, tvb, offset, 1, cigi_byte_order);
+    proto_tree_add_item(tree, hf_cigi3_2_ig_control_minor_version, tvb, offset, 1, cigi_byte_order);
     offset += 2;
 
     /* Get the Byte Swap in Big-Endian so that we can display whether the value
@@ -5819,6 +5828,7 @@ cigi3_2_add_start_of_frame(tvbuff_t *tvb, proto_tree *tree, gint offset)
     proto_tree_add_item(tree, hf_cigi3_2_start_of_frame_ig_mode, tvb, offset, 1, cigi_byte_order);
     proto_tree_add_item(tree, hf_cigi3_2_start_of_frame_timestamp_valid, tvb, offset, 1, cigi_byte_order);
     proto_tree_add_item(tree, hf_cigi3_2_start_of_frame_earth_reference_model, tvb, offset, 1, cigi_byte_order);
+    proto_tree_add_item(tree, hf_cigi3_2_start_of_frame_minor_version, tvb, offset, 1, cigi_byte_order);
     offset++;
 
     /* Get the Byte Swap in Big-Endian so that we can display whether the value
@@ -6555,6 +6565,11 @@ proto_register_cigi(void)
                 FT_BOOLEAN, 8, TFS(&cigi_valid_tfs), 0x04,
                 "Indicates whether the timestamp contains a valid value", HFILL }
         },
+        { &hf_cigi3_2_ig_control_minor_version,
+            { "Minor Version", "cigi.ig_control.minor_version",
+                FT_UINT8, BASE_DEC, NULL, 0xF0,
+                "Indicates the minor version of the CIGI interface", HFILL }
+        },
         { &hf_cigi3_2_ig_control_host_frame_number,
             { "Host Frame Number", "cigi.ig_control.host_frame_number",
                 FT_UINT32, BASE_DEC, NULL, 0x0,
@@ -6598,7 +6613,7 @@ proto_register_cigi(void)
                 "Indicates whether any dead reckoning is enabled.", HFILL }
         },
         { &hf_cigi3_3_ig_control_minor_version,
-            { "Minor Version", "cigi.ig_control.extrapolation_enable",
+            { "Minor Version", "cigi.ig_control.minor_version",
                 FT_UINT8, BASE_DEC, NULL, 0xF0,
                 "Indicates the minor version of the CIGI interface", HFILL }
         },
@@ -10759,6 +10774,11 @@ proto_register_cigi(void)
                 FT_UINT8, BASE_DEC, NULL, 0x0,
                 "Indicates the error status of the IG", HFILL }
         },
+        { &hf_cigi3_2_start_of_frame_minor_version,
+            { "Minor Version", "cigi.sof.minor_version",
+                FT_UINT8, BASE_DEC, NULL, 0xF0,
+                "Indicates the minor version of the CIGI interface", HFILL }
+        },
         { &hf_cigi3_2_start_of_frame_ig_mode,
             { "IG Mode", "cigi.sof.ig_mode",
                 FT_UINT8, BASE_DEC, VALS(cigi3_2_start_of_frame_ig_mode_vals), 0x03,
@@ -10785,7 +10805,7 @@ proto_register_cigi(void)
                 "Indicates the number of 10 microsecond \"ticks\" since some initial reference time", HFILL }
         },
         { &hf_cigi3_2_start_of_frame_last_host_frame_number,
-            { "Last Host Frane Number", "cigi.sof.last_host_frame_number",
+            { "Last Host Frame Number", "cigi.sof.last_host_frame_number",
                 FT_UINT32, BASE_DEC, NULL, 0x0,
                 "Contains the value of the Host Frame parameter in the last IG Control packet received from the Host.", HFILL }
         },