/* Called for the Ethernet Wiretap encapsulation type; pass the FCS length
reported to us, or, if the "assume_fcs" preference is set, pass 4. */
static void
dissect_eth_maybefcs(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
{
proto_tree *fh_tree;
/* Some devices slice the packet and add their own trailer before
putting the frame on the network. Make sure these packets get
a proper trailer (even though the sliced frame might not
properly dissect. */
if ( (eth_trailer_length > 0) && (eth_trailer_length < tvb_length(tvb)) ) {
tvbuff_t *next_tvb;
guint total_trailer_length;
total_trailer_length = eth_trailer_length + (eth_assume_fcs ? 4 : 0);
/* Dissect the tvb up to, but not including the trailer */
next_tvb = tvb_new_subset(tvb, 0,
tvb_length(tvb) - total_trailer_length,
tvb_reported_length(tvb) - total_trailer_length);
fh_tree = dissect_eth_common(next_tvb, pinfo, tree, 0);
/* Now handle the ethernet trailer and optional FCS */
next_tvb = tvb_new_subset_remaining(tvb, tvb_length(tvb) - total_trailer_length);
add_ethernet_trailer(pinfo, tree, fh_tree, hf_eth_trailer, tvb, next_tvb,
eth_assume_fcs ? 4 : pinfo->pseudo_header->eth.fcs_len);
} else {
dissect_eth_common(tvb, pinfo, tree, eth_assume_fcs ? 4 : pinfo->pseudo_header->eth.fcs_len);
}
}
/* Called for the Ethernet Wiretap encapsulation type; pass the FCS length
reported to us, or, if the "assume_fcs" preference is set, pass 4. */
static void
dissect_eth_maybefcs(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
{
dissect_eth_common(tvb, pinfo, tree,
eth_assume_fcs ? 4 :
pinfo->pseudo_header->eth.fcs_len);
}
/* ...and this one's for encapsulated packets that do. */
static void
dissect_eth_withfcs(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
{
dissect_eth_common(tvb, pinfo, tree, 4);
}