void parse_ipv4(packet_in b, Parsed_packet p)
{
b.extract <Ipv4_h>(out p.ip);
vss_model.VSSModel.verify((p.ip.version == 4), error.IPv4IncorrectVersion);
vss_model.VSSModel.verify((p.ip.ihl == 5), error.IPv4OptionsNotSupported);
ck.clear();
ck.update <Ipv4_h>(p.ip);
vss_model.VSSModel.verify((ck.get() == 0), error.IPv4ChecksumError);
accept(b, p);
}
private void parse_ipv4(packet_in b, Parsed_packet p)
{
b.extract(out p.ip);
verify.apply(p.ip.version == (bit4)4, new IPv4IncorrectVersion()); // FIXME how are we handling errors? D: NOTE P4 gives it as error.IPV4IncorrectVersion
verify.apply(p.ip.ihl == (bit4)5, new IPv4OptionsNotSupported());
ck.clear();
ck.update(p.ip);
verify.apply(ck.get() == (bit16)0, new IPv4ChecksumError());
// transition accept
}
public void apply(ref Parsed_packet p, packet_out b)
{
b.emit(p.ethernet);
if (p.ip.isValid())
{
ck.clear();
p.ip.hdrChecksum = (bit16)0;
ck.update(p.ip);
p.ip.hdrChecksum = ck.get();
}
b.emit(p.ip);
}