Use dissect_e212_imsi() to dissect IMSI

Fix dissection when MCC starts in the high nibble.
Replace deprecated APIs

Change-Id: Ic08a1db9ee7ebb535bf7914191807304e9f88981
Reviewed-on: https://code.wireshark.org/review/3736
Reviewed-by: Anders Broman <a.broman58@gmail.com>

1 files changed, 93 insertions, 1 deletions

diff --git a/epan/dissectors/packet-e212.c b/epan/dissectors/packet-e212.c
index 30a07aa52a..c23027d362 100644
--- a/epan/dissectors/packet-e212.c
+++ b/epan/dissectors/packet-e212.c
@@ -2783,6 +2783,94 @@ dissect_e212_mcc_mnc_in_address(tvbuff_t *tvb, packet_info *pinfo, proto_tree *t
         return 5;
 }
 
+/*
+ * MNC of length 2:
+ *
+ *     8   7   6   5   4   3   2   1
+ *   +---+---+---+---+---+---+---+---+
+ *   |  MCC digit 1  |  Other data   |  octet x
+ *   +---------------+---------------+
+ *   |  MNC digit 1  |  MCC digit 2  |  octet x+1
+ *   +---------------+---------------+
+ *   | MNC digit  3  |  MNC digit 2  |  octet x+2
+ *   +---------------+---------------+
+ *
+ * MNC of length 3:
+ *
+ *     8   7   6   5   4   3   2   1
+ *   +---+---+---+---+---+---+---+---+
+ *   |  MCC digit 1  |  Other data   |  octet x
+ *   +---------------+---------------+
+ *   |  MCC digit 3  |  MCC digit 2  |  octet x+1
+ *   +---------------+---------------+
+ *   |  MNC digit 2  |  MNC digit 1  |  octet x+2
+ *   +---------------+---------------+
+ *   |  .....        |  MNC digit 3  |  octet x+3
+ *   +---------------+---------------+
+ */
+static int
+dissect_e212_mcc_mnc_high_nibble(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int offset)
+{
+
+    guint32     start_offset;
+    guint8      octet;
+    guint16     mcc, mnc;
+    guint8      mcc1, mcc2, mcc3, mnc1, mnc2, mnc3;
+    proto_item *item;
+    gboolean    long_mnc;
+
+    long_mnc = FALSE;
+    start_offset = offset;
+
+    /* MCC digits 1 */
+    octet = tvb_get_guint8(tvb,offset);
+    mcc1  = octet >> 4;
+    offset++;
+
+    /* MCC digits 1 and 2 */
+    octet = tvb_get_guint8(tvb,offset);
+    mcc2  = octet & 0x0f;
+    mcc3  = octet >> 4;
+    offset++;
+
+	/* MNC digit 1 and MNC digit 2 */
+    octet = tvb_get_guint8(tvb,offset);
+    mnc1  = octet & 0x0f;
+    mnc2  = octet >> 4;
+    offset++;
+
+    /* MNC digits 3 */
+    octet = tvb_get_guint8(tvb,offset);
+    mnc3  = octet & 0x0f;
+
+    mcc   = 100 * mcc1 + 10 * mcc2 + mcc3;
+    mnc   = 10 * mnc1 + mnc2;
+
+    /* Try to match the MCC and 2 digits MNC with an entry in our list of operators */
+    if (!try_val_to_str_ext(mcc * 1000 + 10 * mnc, &mcc_mnc_codes_ext)) {
+        mnc = 10 * mnc + mnc3;
+        long_mnc = TRUE;
+    }
+
+    item = proto_tree_add_uint(tree, hf_E212_mcc , tvb, start_offset, 2, mcc );
+
+    if (long_mnc)
+        item = proto_tree_add_uint_format_value(tree, hf_E212_mnc , tvb, start_offset + 1, 2, mnc,
+                   "%s (%03u)",
+                   val_to_str_ext_const(mcc * 1000 + mnc, &mcc_mnc_codes_ext, "Unknown"),
+                   mnc);
+    else
+        item = proto_tree_add_uint_format_value(tree, hf_E212_mnc , tvb, start_offset + 1, 2, mnc,
+                   "%s (%02u)",
+                   val_to_str_ext_const(mcc * 1000 + 10 * mnc, &mcc_mnc_codes_ext, "Unknown"),
+                   mnc);
+
+    if (long_mnc)
+        return 7;
+    else
+        return 5;
+
+}
 const gchar *
 dissect_e212_imsi(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int offset, int length, gboolean skip_first)
 {
@@ -2799,7 +2887,11 @@ dissect_e212_imsi(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int offse
 
     subtree = proto_item_add_subtree(item, ett_e212_imsi);
 
-    dissect_e212_mcc_mnc_in_address(tvb, pinfo, subtree, offset);
+	if(skip_first){
+	    dissect_e212_mcc_mnc_high_nibble(tvb, pinfo, subtree, offset);
+	}else{
+	    dissect_e212_mcc_mnc_in_address(tvb, pinfo, subtree, offset);
+	}
 
     return imsi_str;
 }