Add proto_tree_add_checksum.

This is an attempt to standardize display/handling of checksum fields for all dissectors.
The main target is for dissectors that do validation, but dissectors that just report the
checksum were also included just to make them easier to find in the future.

Bug: 10620
Bug: 12058
Ping-Bug: 8859
Change-Id: Ia8abd86e42eaf8ed50de6b173409e914b17993bf
Reviewed-on: https://code.wireshark.org/review/16380
Petri-Dish: Michael Mann <mmann78@netscape.net>
Tested-by: Petri Dish Buildbot <buildbot-no-reply@wireshark.org>
Reviewed-by: Jeff Morriss <jeff.morriss.ws@gmail.com>
Reviewed-by: Michael Mann <mmann78@netscape.net>

1 files changed, 24 insertions, 44 deletions

diff --git a/epan/dissectors/packet-sctp.c b/epan/dissectors/packet-sctp.c
index 106a1e954b..8c7a8ba36a 100644
--- a/epan/dissectors/packet-sctp.c
+++ b/epan/dissectors/packet-sctp.c
@@ -94,7 +94,9 @@ static int hf_source_port      = -1;
 static int hf_destination_port = -1;
 static int hf_verification_tag = -1;
 static int hf_checksum         = -1;
-static int hf_checksum_bad     = -1;
+static int hf_checksum_adler   = -1;
+static int hf_checksum_crc32c  = -1;
+static int hf_checksum_status  = -1;
 
 static int hf_chunk_type       = -1;
 static int hf_chunk_flags      = -1;
@@ -272,7 +274,6 @@ static int exported_pdu_tap = -1;
 
 /* Initialize the subtree pointers */
 static gint ett_sctp = -1;
-static gint ett_sctp_checksum = -1;
 static gint ett_sctp_chunk = -1;
 static gint ett_sctp_chunk_parameter = -1;
 static gint ett_sctp_chunk_cause = -1;
@@ -4573,8 +4574,8 @@ dissect_sctp_packet(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, gboolea
   guint16 source_port, destination_port;
   guint captured_length, reported_length;
   gboolean crc32c_correct = FALSE, adler32_correct = FALSE;
-  proto_item *sctp_item, *hidden_item, *item;
-  proto_tree *sctp_tree, *checksum_tree;
+  proto_item *sctp_item, *hidden_item;
+  proto_tree *sctp_tree;
   guint32 vtag;
   sctp_half_assoc_t *ha = NULL;
   proto_item *pi, *vt = NULL;
@@ -4654,58 +4655,36 @@ dissect_sctp_packet(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, gboolea
 
     switch(sctp_checksum) {
     case SCTP_CHECKSUM_NONE:
-      proto_tree_add_uint_format_value(sctp_tree, hf_checksum, tvb, CHECKSUM_OFFSET, CHECKSUM_LENGTH, checksum, "0x%08x (not verified)", checksum);
+      proto_tree_add_checksum(sctp_tree, tvb, CHECKSUM_OFFSET, hf_checksum, hf_checksum_status, &ei_sctp_bad_sctp_checksum, pinfo, 0,
+                              ENC_BIG_ENDIAN, PROTO_CHECKSUM_NO_FLAGS);
       break;
     case SCTP_CHECKSUM_ADLER32:
-      if (adler32_correct)
-        item = proto_tree_add_uint_format_value(sctp_tree, hf_checksum, tvb, CHECKSUM_OFFSET, CHECKSUM_LENGTH,
-                                                checksum, "0x%08x [correct Adler32]", checksum);
-      else {
-        item = proto_tree_add_uint_format_value(sctp_tree, hf_checksum, tvb, CHECKSUM_OFFSET, CHECKSUM_LENGTH, checksum,
-                                                "0x%08x [incorrect Adler32, should be 0x%08x]",
-                                                checksum, calculated_adler32);
-        expert_add_info(pinfo, item, &ei_sctp_bad_sctp_checksum);
-      }
-      checksum_tree = proto_item_add_subtree(item, ett_sctp_checksum);
-      proto_tree_add_boolean(checksum_tree, hf_checksum_bad, tvb, CHECKSUM_OFFSET, CHECKSUM_LENGTH, !(adler32_correct));
+      proto_tree_add_checksum(sctp_tree, tvb, CHECKSUM_OFFSET, hf_checksum_adler, hf_checksum_status, &ei_sctp_bad_sctp_checksum, pinfo, calculated_adler32,
+                              ENC_BIG_ENDIAN, PROTO_CHECKSUM_VERIFY);
       break;
     case SCTP_CHECKSUM_CRC32C:
-      if (crc32c_correct)
-        item = proto_tree_add_uint_format_value(sctp_tree, hf_checksum, tvb, CHECKSUM_OFFSET, CHECKSUM_LENGTH,
-                                                checksum, "0x%08x [correct CRC32C]", checksum);
-      else {
-        item = proto_tree_add_uint_format_value(sctp_tree, hf_checksum, tvb, CHECKSUM_OFFSET, CHECKSUM_LENGTH, checksum,
-                                                "0x%08x [incorrect CRC32C, should be 0x%08x]",
-                                                checksum, calculated_crc32c);
-        expert_add_info(pinfo, item, &ei_sctp_bad_sctp_checksum);
-      }
-      checksum_tree = proto_item_add_subtree(item, ett_sctp_checksum);
-      proto_tree_add_boolean(checksum_tree, hf_checksum_bad, tvb, CHECKSUM_OFFSET, CHECKSUM_LENGTH, !(crc32c_correct));
+      proto_tree_add_checksum(sctp_tree, tvb, CHECKSUM_OFFSET, hf_checksum_crc32c, hf_checksum_status, &ei_sctp_bad_sctp_checksum, pinfo, calculated_crc32c,
+                              ENC_BIG_ENDIAN, PROTO_CHECKSUM_VERIFY);
       break;
     case SCTP_CHECKSUM_AUTOMATIC:
       if ((adler32_correct) && !(crc32c_correct))
-        item = proto_tree_add_uint_format_value(sctp_tree, hf_checksum, tvb, CHECKSUM_OFFSET, CHECKSUM_LENGTH,
-                                                checksum, "0x%08x [correct Adler32]", checksum);
+        proto_tree_add_checksum(sctp_tree, tvb, CHECKSUM_OFFSET, hf_checksum_adler, hf_checksum_status, &ei_sctp_bad_sctp_checksum, pinfo, calculated_adler32,
+                              ENC_BIG_ENDIAN, PROTO_CHECKSUM_VERIFY);
       else if ((!adler32_correct) && (crc32c_correct))
-        item = proto_tree_add_uint_format_value(sctp_tree, hf_checksum, tvb, CHECKSUM_OFFSET, CHECKSUM_LENGTH,
-                                                checksum, "0x%08x [correct CRC32C]", checksum);
-      else if ((adler32_correct) && (crc32c_correct))
-        item = proto_tree_add_uint_format_value(sctp_tree, hf_checksum, tvb, CHECKSUM_OFFSET, CHECKSUM_LENGTH,
-                                                checksum, "0x%08x [correct Adler32 and CRC32C]", checksum);
+        proto_tree_add_checksum(sctp_tree, tvb, CHECKSUM_OFFSET, hf_checksum_crc32c, hf_checksum_status, &ei_sctp_bad_sctp_checksum, pinfo, calculated_crc32c,
+                              ENC_BIG_ENDIAN, PROTO_CHECKSUM_VERIFY);
       else {
-        item = proto_tree_add_uint_format_value(sctp_tree, hf_checksum, tvb, CHECKSUM_OFFSET, CHECKSUM_LENGTH, checksum,
-                                                "0x%08x [incorrect, should be 0x%08x (Adler32) or 0x%08x (CRC32C)]",
-                                                checksum, calculated_adler32, calculated_crc32c);
-        expert_add_info(pinfo, item, &ei_sctp_bad_sctp_checksum);
+        proto_tree_add_checksum(sctp_tree, tvb, CHECKSUM_OFFSET, hf_checksum_adler, hf_checksum_status, &ei_sctp_bad_sctp_checksum, pinfo, calculated_adler32,
+                              ENC_BIG_ENDIAN, PROTO_CHECKSUM_VERIFY);
+        proto_tree_add_checksum(sctp_tree, tvb, CHECKSUM_OFFSET, hf_checksum_crc32c, hf_checksum_status, &ei_sctp_bad_sctp_checksum, pinfo, calculated_crc32c,
+                              ENC_BIG_ENDIAN, PROTO_CHECKSUM_VERIFY);
       }
-      checksum_tree = proto_item_add_subtree(item, ett_sctp_checksum);
-      proto_tree_add_boolean(checksum_tree, hf_checksum_bad, tvb, CHECKSUM_OFFSET, CHECKSUM_LENGTH, !(crc32c_correct || adler32_correct));
       break;
     }
   } else {
     /* We don't have the whole packet so we can't verify the checksum */
-    proto_tree_add_uint_format_value(sctp_tree, hf_checksum, tvb, CHECKSUM_OFFSET, CHECKSUM_LENGTH,
-                               checksum, "0x%08x [unchecked, not all data available]", checksum);
+      proto_tree_add_checksum(sctp_tree, tvb, CHECKSUM_OFFSET, hf_checksum, hf_checksum_status, &ei_sctp_bad_sctp_checksum, pinfo, 0,
+                              ENC_BIG_ENDIAN, PROTO_CHECKSUM_NO_FLAGS);
   }
 
   /* add all chunks of the sctp datagram to the protocol tree */
@@ -4789,7 +4768,9 @@ proto_register_sctp(void)
     { &hf_port,                                     { "Port",                                           "sctp.port",                                            FT_UINT16,  BASE_PT_SCTP, NULL,                                        0x0,                                NULL, HFILL } },
     { &hf_verification_tag,                         { "Verification tag",                               "sctp.verification_tag",                                FT_UINT32,  BASE_HEX,  NULL,                                           0x0,                                NULL, HFILL } },
     { &hf_checksum,                                 { "Checksum",                                       "sctp.checksum",                                        FT_UINT32,  BASE_HEX,  NULL,                                           0x0,                                NULL, HFILL } },
-    { &hf_checksum_bad,                             { "Bad checksum",                                   "sctp.checksum_bad",                                    FT_BOOLEAN, BASE_NONE, NULL,                                           0x0,                                NULL, HFILL } },
+    { &hf_checksum_adler,                           { "Checksum (Adler)",                               "sctp.checksum",                                        FT_UINT32,  BASE_HEX,  NULL,                                           0x0,                                NULL, HFILL } },
+    { &hf_checksum_crc32c,                          { "Checksum (CRC32C)",                              "sctp.checksum",                                        FT_UINT32,  BASE_HEX,  NULL,                                           0x0,                                NULL, HFILL } },
+    { &hf_checksum_status,                          { "Checksum Status",                                "sctp.checksum.status",                                 FT_UINT8,   BASE_NONE, VALS(proto_checksum_vals),                      0x0,                                NULL, HFILL } },
     { &hf_chunk_type,                               { "Chunk type",                                     "sctp.chunk_type",                                      FT_UINT8,   BASE_DEC,  VALS(chunk_type_values),                        0x0,                                NULL, HFILL } },
     { &hf_chunk_flags,                              { "Chunk flags",                                    "sctp.chunk_flags",                                     FT_UINT8,   BASE_HEX,  NULL,                                           0x0,                                NULL, HFILL } },
     { &hf_chunk_bit_1,                              { "Bit",                                            "sctp.chunk_bit_1",                                     FT_BOOLEAN, 8,         TFS(&sctp_chunk_bit_1_value),                   SCTP_CHUNK_BIT_1,                   NULL, HFILL } },
@@ -4944,7 +4925,6 @@ proto_register_sctp(void)
   /* Setup protocol subtree array */
   static gint *ett[] = {
     &ett_sctp,
-    &ett_sctp_checksum,
     &ett_sctp_chunk,
     &ett_sctp_chunk_parameter,
     &ett_sctp_chunk_cause,