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Diffstat (limited to 'epan/dissectors/packet-batadv.c')
-rw-r--r--epan/dissectors/packet-batadv.c99
1 files changed, 92 insertions, 7 deletions
diff --git a/epan/dissectors/packet-batadv.c b/epan/dissectors/packet-batadv.c
index c59d5efbdc..b56bc6f183 100644
--- a/epan/dissectors/packet-batadv.c
+++ b/epan/dissectors/packet-batadv.c
@@ -18,6 +18,8 @@
#include <epan/reassemble.h>
#include <epan/expert.h>
+#include <wsutil/crc32.h>
+
/* Start content from packet-batadv.h */
#define ETH_P_BATMAN 0x4305
@@ -423,6 +425,10 @@ struct unicast_tvlv_packet_v15 {
guint16 align;
};
#define UNICAST_TVLV_PACKET_V15_SIZE 20
+
+#define TLVLV_TT_VLAN_V15_SIZE 8
+#define TLVLV_TT_CHANGE_V15_SIZE 12
+
/* End content from packet-batadv.h */
/* trees */
@@ -457,6 +463,8 @@ static gint ett_msg_fragment = -1;
static gint ett_msg_fragments = -1;
static expert_field ei_batadv_tvlv_unknown_version = EI_INIT;
+static expert_field ei_batadv_tvlv_tt_vlan_crc = EI_INIT;
+static expert_field ei_batadv_tvlv_tt_vlan_empty = EI_INIT;
/* hfs */
static int hf_batadv_packet_type = -1;
@@ -609,6 +617,7 @@ static int hf_batadv_tvlv_tt_flags_full_table = -1;
static int hf_batadv_tvlv_tt_ttvn = -1;
static int hf_batadv_tvlv_tt_num_vlan = -1;
static int hf_batadv_tvlv_tt_vlan_crc = -1;
+static int hf_batadv_tvlv_tt_vlan_crc_status = -1;
static int hf_batadv_tvlv_tt_vlan_vid = -1;
static int hf_batadv_tvlv_tt_change_flags = -1;
static int hf_batadv_tvlv_tt_change_vid = -1;
@@ -812,7 +821,7 @@ static void dissect_batadv_tvlv_v15_mcast(tvbuff_t *tvb, packet_info *pinfo _U_,
static void dissect_batadv_tvlv_v15_gw(tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree, int offset, guint8 version);
static void dissect_batadv_tvlv_v15_roam(tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree, int offset, guint8 version);
static void dissect_batadv_tvlv_v15_tt(tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree, int offset, guint8 version);
-static int dissect_batadv_tvlv_v15_tt_vlan(tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree, int offset);
+static int dissect_batadv_tvlv_v15_tt_vlan(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, int offset, guint8 tt_flags, int changes_offset);
static int dissect_batadv_tvlv_v15_tt_change(tvbuff_t *tvb, packet_info *pinfo _U_, proto_tree *tree, int offset);
@@ -4057,6 +4066,10 @@ static void dissect_batadv_tvlv_v15_tt(tvbuff_t *tvb, packet_info *pinfo,
&hf_batadv_tvlv_tt_flags_full_table,
NULL
};
+ guint8 tt_flags;
+ int changes_offset;
+
+ tt_flags = tvb_get_guint8(tvb, offset);
if (version != 0x01) {
proto_tree_add_expert_format(
@@ -4078,9 +4091,12 @@ static void dissect_batadv_tvlv_v15_tt(tvbuff_t *tvb, packet_info *pinfo,
ENC_BIG_ENDIAN);
offset += 2;
+ changes_offset = offset + num_vlan * TLVLV_TT_VLAN_V15_SIZE;
+
for (i = 0; i < num_vlan; i++)
offset = dissect_batadv_tvlv_v15_tt_vlan(tvb, pinfo, tree,
- offset);
+ offset, tt_flags,
+ changes_offset);
length_remaining = tvb_reported_length_remaining(tvb, offset);
while (length_remaining > 0) {
@@ -4090,12 +4106,74 @@ static void dissect_batadv_tvlv_v15_tt(tvbuff_t *tvb, packet_info *pinfo,
}
}
+static void dissect_batadv_tvlv_v15_tt_vlan_checksum(tvbuff_t *tvb,
+ proto_item *ti,
+ packet_info *pinfo,
+ proto_tree *tree,
+ guint16 vlan_id,
+ int crc_offset,
+ guint8 tt_flags,
+ int offset)
+{
+ const guint8 *buf;
+ guint32 crc32;
+ guint32 crc = 0;
+ gint length_remaining;
+ guint16 vid;
+ unsigned int num_entries = 0;
+ guint8 full_response = (BATADV_TVLVL_TT_RESPONSE | BATADV_TVLVL_TT_FULL_TABLE);
+
+ /* checksum checks are not possible with non full responses */
+ if (tt_flags != full_response) {
+ proto_tree_add_item(tree, hf_batadv_tvlv_tt_vlan_crc, tvb,
+ crc_offset, 4, ENC_BIG_ENDIAN);
+ return;
+ }
+
+ length_remaining = tvb_reported_length_remaining(tvb, offset);
+ while (length_remaining >= TLVLV_TT_CHANGE_V15_SIZE) {
+
+ vid = tvb_get_ntohs(tvb, offset + 10);
+ if (vid != vlan_id)
+ goto skip;
+
+ buf = tvb_get_ptr(tvb, offset, TLVLV_TT_CHANGE_V15_SIZE);
+ if (!buf)
+ goto skip;
+
+ num_entries++;
+
+ /* checksum over vid, flags, address */
+ crc32 = 0;
+ crc32 = crc32c_calculate_no_swap(&buf[10], 2, crc32);
+ crc32 = crc32c_calculate_no_swap(buf, 1, crc32);
+ crc32 = crc32c_calculate_no_swap(&buf[4], 6, crc32);
+ crc ^= crc32;
+
+skip:
+ offset += TLVLV_TT_CHANGE_V15_SIZE;
+ length_remaining = tvb_reported_length_remaining(tvb, offset);
+ }
+
+ proto_tree_add_checksum(tree, tvb, crc_offset,
+ hf_batadv_tvlv_tt_vlan_crc,
+ hf_batadv_tvlv_tt_vlan_crc_status,
+ &ei_batadv_tvlv_tt_vlan_crc, pinfo, crc,
+ ENC_BIG_ENDIAN, PROTO_CHECKSUM_VERIFY);
+
+ if (num_entries == 0)
+ expert_add_info(pinfo, ti, &ei_batadv_tvlv_tt_vlan_empty);
+}
+
static int dissect_batadv_tvlv_v15_tt_vlan(tvbuff_t *tvb,
- packet_info *pinfo _U_,
- proto_tree *tree, int offset)
+ packet_info *pinfo,
+ proto_tree *tree, int offset,
+ guint8 tt_flags,
+ int changes_offset)
{
proto_tree *vlan_tree = NULL;
guint16 vid;
+ proto_item *ti = NULL;
static const int * flags[] = {
&hf_batadv_tvlv_vid_vlan,
&hf_batadv_tvlv_vid_tagged,
@@ -4106,7 +4184,6 @@ static int dissect_batadv_tvlv_v15_tt_vlan(tvbuff_t *tvb,
/* Set tree info */
if (tree) {
- proto_item *ti;
ti = proto_tree_add_protocol_format(tree, proto_batadv_plugin,
tvb, offset, 8,
@@ -4114,8 +4191,9 @@ static int dissect_batadv_tvlv_v15_tt_vlan(tvbuff_t *tvb,
vlan_tree = proto_item_add_subtree(ti, ett_batadv_tvlv_tt_vlan);
}
- proto_tree_add_item(vlan_tree, hf_batadv_tvlv_tt_vlan_crc, tvb, offset,
- 4, ENC_BIG_ENDIAN);
+ dissect_batadv_tvlv_v15_tt_vlan_checksum(tvb, ti, pinfo, vlan_tree, vid,
+ offset, tt_flags,
+ changes_offset);
offset += 4;
proto_tree_add_bitmask(vlan_tree, tvb, offset,
@@ -4908,6 +4986,11 @@ void proto_register_batadv(void)
FT_UINT32, BASE_HEX, NULL, 0x0,
NULL, HFILL }
},
+ { &hf_batadv_tvlv_tt_vlan_crc_status,
+ { "Checksum Status", "batadv.tvlv.tt.vlan.crc.status",
+ FT_UINT8, BASE_NONE, VALS(proto_checksum_vals), 0x0,
+ NULL, HFILL }
+ },
{ &hf_batadv_tvlv_tt_vlan_vid,
{ "VID", "batadv.tvlv.tt.vlan.vid",
FT_UINT16, BASE_HEX, NULL, 0x0,
@@ -4989,6 +5072,8 @@ void proto_register_batadv(void)
static ei_register_info ei[] = {
{ &ei_batadv_tvlv_unknown_version, { "batadv.error.tvlv_version_unknown", PI_UNDECODED, PI_ERROR, "BATADV Error: unknown TVLV version", EXPFILL }},
+ { &ei_batadv_tvlv_tt_vlan_crc, { "batadv.tvlv_tt_crc_bad", PI_UNDECODED, PI_ERROR, "BATADV Error: bad TT VLAN crc", EXPFILL }},
+ { &ei_batadv_tvlv_tt_vlan_empty, { "batadv.tvlv_tt_vlan_empty", PI_SEQUENCE, PI_WARN, "BATADV Warn: empty VLAN", EXPFILL }},
};
proto_batadv_plugin = proto_register_protocol(
generated by cgit v1.2.3 (git 2.25.1) at 2024-06-08 19:29:29 +0000