public virtual bool isMessageOfType(UDP udp, IPv4 ipv4, int messageType)
{
if (opcode != DHCP_BOOT_REQUEST)
{
return(false);
}
if (udp.sourcePort != UDP_PORT_DHCP_CLIENT || udp.destinationPort != UDP_PORT_DHCP_SERVER)
{
return(false);
}
if (!Array.Equals(ipv4.sourceIPAddress, nullIPAddress))
{
return(false);
}
if (!Array.Equals(ipv4.destinationIPAddress, broadcastIPAddress))
{
return(false);
}
DHCPOption option = getOptionByTag(DHCP_OPTION_MESSAGE_TYPE);
if (option == null || option.Length != 1)
{
return(false);
}
int optionMessageType = option.DataAsInt;
if (optionMessageType != messageType)
{
return(false);
}
return(true);
}
public IPv4(IPv4 ipv4)
{
version = ipv4.version;
internetHeaderLength = ipv4.internetHeaderLength;
differentiatedServicesCodePoint = ipv4.differentiatedServicesCodePoint;
explicitCongestionNotification = ipv4.explicitCongestionNotification;
totalLength = ipv4.totalLength;
identification = ipv4.identification;
flags = ipv4.flags;
fragmentOffset = ipv4.fragmentOffset;
timeToLive = ipv4.timeToLive;
protocol = ipv4.protocol;
headerChecksum = ipv4.headerChecksum;
sourceIPAddress = ipv4.sourceIPAddress;
destinationIPAddress = ipv4.destinationIPAddress;
options = ipv4.options;
}
public virtual bool isRequest(UDP udp, IPv4 ipv4, sbyte[] requestedIpAddress)
{
if (!isMessageOfType(udp, ipv4, DHCP_OPTION_MESSAGE_TYPE_DHCPREQUEST))
{
return(false);
}
// Verify that the requested IP address is matching
// the one specified in the options.
DHCPOption requestedIpAddressOption = getOptionByTag(DHCP_OPTION_REQUESTED_IP_ADDRESS);
if (requestedIpAddressOption == null || requestedIpAddressOption.Length != 4)
{
return(false);
}
if (!Array.Equals(requestedIpAddress, requestedIpAddressOption.data))
{
return(false);
}
return(true);
}
//JAVA TO C# CONVERTER WARNING: Method 'throws' clauses are not available in .NET:
//ORIGINAL LINE: public void computeChecksum(IPv4 ipv4) throws java.io.EOFException
public virtual void computeChecksum(IPv4 ipv4)
{
// Computes the checksum with 0 at the checksum FieldInfo
checksum = 0;
// The checksum also covers a 12 bytes pseudo header
NetPacket checksumPacket = new NetPacket(12 + sizeOf());
// Pseudo header:
// - source IP address (4 bytes)
// - destination IP address (4 bytes)
// - 0 (1 byte)
// - protocol (1 byte)
// - TCP Length (2 bytes)
checksumPacket.writeBytes(ipv4.sourceIPAddress);
checksumPacket.writeBytes(ipv4.destinationIPAddress);
checksumPacket.write8(0);
checksumPacket.write8(ipv4.protocol);
checksumPacket.write16(sizeOf());
write(checksumPacket);
checksum = computeInternetChecksum(checksumPacket.Buffer, 0, checksumPacket.Offset);
}
public virtual bool isDiscovery(UDP udp, IPv4 ipv4)
{
return(isMessageOfType(udp, ipv4, DHCP_OPTION_MESSAGE_TYPE_DHCPDISCOVER));
}
