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-rw-r--r--epan/dissectors/packet-ositp.c61
1 files changed, 23 insertions, 38 deletions
diff --git a/epan/dissectors/packet-ositp.c b/epan/dissectors/packet-ositp.c
index 53d7328b75..08c671211d 100644
--- a/epan/dissectors/packet-ositp.c
+++ b/epan/dissectors/packet-ositp.c
@@ -68,7 +68,8 @@ static int hf_cotp_eot_extended = -1;
static int hf_cotp_parameter_code = -1;
static int hf_cotp_parameter_length = -1;
static int hf_cotp_parameter_value = -1;
-static int hf_cotp_atn_extended_checksum = -1;
+static int hf_cotp_atn_extended_checksum16 = -1;
+static int hf_cotp_atn_extended_checksum32 = -1;
static int hf_cotp_ack_time = -1;
static int hf_cotp_res_error_rate_target_value = -1;
static int hf_cotp_res_error_rate_min_accept = -1;
@@ -440,10 +441,8 @@ static gboolean ositp_decode_var_part(tvbuff_t *tvb, int offset, int vp_length,
gint32 i = 0;
guint8 tmp_code = 0;
guint tmp_len = 0;
- cksum_status_t cksum_status;
- gboolean checksum_ok = FALSE;
guint32 pref_max_tpdu_size;
- proto_item *ti, *hidden_item;
+ proto_item *hidden_item;
while (vp_length != 0) {
code = tvb_get_guint8(tvb, offset);
@@ -462,6 +461,7 @@ static gboolean ositp_decode_var_part(tvbuff_t *tvb, int offset, int vp_length,
case VP_ATN_EC_16 : /* ATN */
if (cotp_decode_atn) {
+ guint16 sum;
/* if an alternate OSI checksum is present in the currently unprocessed
* VP section to the checksum algorithm has to know.
* this may be the case for backward compatible CR TPDU */
@@ -477,12 +477,11 @@ static gboolean ositp_decode_var_part(tvbuff_t *tvb, int offset, int vp_length,
i += tmp_len;
}
}
- checksum_ok = check_atn_ec_16(tvb, tpdu_len , offset,
+ sum = check_atn_ec_16(tvb, tpdu_len , offset,
offset_iso8073_checksum,
pinfo->dst.len, (const guint8 *)pinfo->dst.data,
pinfo->src.len, (const guint8 *)pinfo->src.data);
- ti = proto_tree_add_item(tree, hf_cotp_atn_extended_checksum, tvb, offset, 2, ENC_BIG_ENDIAN);
- proto_item_append_text(ti, checksum_ok ? " (correct)" : " (incorrect)");
+ proto_tree_add_checksum(tree, tvb, offset, hf_cotp_atn_extended_checksum16, -1, NULL, pinfo, sum, ENC_BIG_ENDIAN, PROTO_CHECKSUM_VERIFY|PROTO_CHECKSUM_ZERO);
} else {
proto_tree_add_bytes_format_value(tree, hf_cotp_parameter_value, tvb, offset, length, NULL, "<not shown>");
}
@@ -492,6 +491,7 @@ static gboolean ositp_decode_var_part(tvbuff_t *tvb, int offset, int vp_length,
case VP_ATN_EC_32 : /* ATN */
if (cotp_decode_atn) {
+ guint32 sum;
/* if an alternate OSI checksum is present in the currently unprocessed
* VP section the checksum algorithm has to know.
* this may be the case for backward compatible CR TPDU */
@@ -507,12 +507,11 @@ static gboolean ositp_decode_var_part(tvbuff_t *tvb, int offset, int vp_length,
i += tmp_len;
}
}
- checksum_ok = check_atn_ec_32(tvb, tpdu_len , offset,
+ sum = check_atn_ec_32(tvb, tpdu_len , offset,
offset_iso8073_checksum,
pinfo->dst.len, (const guint8 *)pinfo->dst.data,
pinfo->src.len, (const guint8 *)pinfo->src.data);
- ti = proto_tree_add_item(tree, hf_cotp_atn_extended_checksum, tvb, offset, 4, ENC_BIG_ENDIAN);
- proto_item_append_text(ti, checksum_ok ? " (correct)" : " (incorrect)");
+ proto_tree_add_checksum(tree, tvb, offset, hf_cotp_atn_extended_checksum32, -1, NULL, pinfo, sum, ENC_BIG_ENDIAN, PROTO_CHECKSUM_VERIFY|PROTO_CHECKSUM_ZERO);
} else {
proto_tree_add_bytes_format_value(tree, hf_cotp_parameter_value, tvb, offset, length, NULL, "<not shown>");
}
@@ -691,36 +690,21 @@ static gboolean ositp_decode_var_part(tvbuff_t *tvb, int offset, int vp_length,
case VP_CHECKSUM:
offset_iso8073_checksum = offset; /* save ISO 8073 checksum offset for ATN extended checksum calculation */
- cksum_status = calc_checksum(tvb, 0, tpdu_len,
- tvb_get_ntohs(tvb, offset));
- switch (cksum_status) {
- default:
- /*
- * No checksum present, or not enough of the packet present to
- * checksum it.
- */
- proto_tree_add_item(tree, hf_cotp_checksum, tvb, offset, 2, ENC_BIG_ENDIAN);
- break;
-
- case CKSUM_OK:
- /*
- * Checksum is correct.
- */
- s = tvb_get_ntohs(tvb, offset);
- proto_tree_add_uint_format_value(tree, hf_cotp_checksum, tvb, offset, 2,
- s, "0x%04x (correct)", s);
- break;
+ if (tvb_get_ntohs(tvb, offset) == 0) {
+ /* No checksum present */
+ proto_tree_add_checksum(tree, tvb, offset, hf_cotp_checksum, -1, NULL, pinfo, 0, ENC_BIG_ENDIAN, PROTO_CHECKSUM_NOT_PRESENT);
+ } else {
+ guint32 calc_c0 = 0, calc_c1 = 0;
- case CKSUM_NOT_OK:
- /*
- * Checksum is not correct.
- */
- s = tvb_get_ntohs(tvb, offset);
- proto_tree_add_uint_format_value(tree, hf_cotp_checksum, tvb, offset, 2,
- s, "0x%04x (incorrect)", s);
- break;
+ if (osi_calc_checksum(tvb, 0, length, &calc_c0, &calc_c1)) {
+ /* Successfully processed checksum, verify it */
+ proto_tree_add_checksum(tree, tvb, offset, hf_cotp_checksum, -1, NULL, pinfo, calc_c0 | calc_c1, ENC_BIG_ENDIAN, PROTO_CHECKSUM_VERIFY|PROTO_CHECKSUM_ZERO);
+ } else {
+ proto_tree_add_checksum(tree, tvb, offset, hf_cotp_checksum, -1, NULL, pinfo, 0, ENC_BIG_ENDIAN, PROTO_CHECKSUM_NO_FLAGS);
+ }
}
+
offset += length;
vp_length -= length;
break;
@@ -2338,7 +2322,8 @@ void proto_register_cotp(void)
{ &hf_cotp_parameter_code, { "Parameter code", "cotp.parameter_code", FT_UINT8, BASE_HEX, VALS(tp_vpart_type_vals), 0x0, NULL, HFILL }},
{ &hf_cotp_parameter_length, { "Parameter length", "cotp.parameter_length", FT_UINT8, BASE_DEC, NULL, 0x0, NULL, HFILL }},
{ &hf_cotp_parameter_value, { "Parameter value", "cotp.parameter_value", FT_BYTES, BASE_NONE, NULL, 0x0, NULL, HFILL }},
- { &hf_cotp_atn_extended_checksum, { "ATN extended checksum", "cotp.atn_extended_checksum", FT_UINT32, BASE_HEX, NULL, 0x0, NULL, HFILL }},
+ { &hf_cotp_atn_extended_checksum16, { "ATN extended checksum", "cotp.atn_extended_checksum", FT_UINT16, BASE_HEX, NULL, 0x0, NULL, HFILL }},
+ { &hf_cotp_atn_extended_checksum32, { "ATN extended checksum", "cotp.atn_extended_checksum", FT_UINT32, BASE_HEX, NULL, 0x0, NULL, HFILL }},
{ &hf_cotp_ack_time, { "Ack time (ms)", "cotp.ack_time", FT_UINT16, BASE_DEC, NULL, 0x0, NULL, HFILL }},
{ &hf_cotp_res_error_rate_target_value, { "Residual error rate, target value", "cotp.res_error_rate.target_value", FT_UINT8, BASE_DEC, NULL, 0x0, NULL, HFILL }},
{ &hf_cotp_res_error_rate_min_accept, { "Residual error rate, minimum acceptable", "cotp.res_error_rate.min_accept", FT_UINT8, BASE_DEC, NULL, 0x0, NULL, HFILL }},
generated by cgit v1.2.3 (git 2.25.1) at 2024-09-24 18:45:31 +0000