Free dhcp software for linux

ISC DHCP provides a freely redistributable reference implementation of all aspects of DHCP, through a suite of DHCP tools:
- A DHCP server
- A DHCP client
- A DHCP relay agent
These tools all use a modular API which is designed to be sufficiently general that it can easily be made to work on POSIX-compliant operating systems and also non-POSIX systems like Windows NT and MacOS.
The DHCP server, client and relay agent are provided both as reference implementations of the protocol and as working, fully-featured sample implementations.
Both the client and the server provide functionality that, while not strictly required by the protocol, is very useful in practice. DHCP server also makes allowances for non-compliant clients which one might still like to support.

dhcp2ldap is a perl daemon that I’ve written to work with the LDAP SDB backend for Bind9, and the ISC DHCP server.

It will check the dhcp leases file, at a configurable rate, for changes and update DNS accordingly.

watchDhcp is a simple script that lets you watch and react to a change in the systems IP address. It is useful for automatically reconfiguring NAT, DNS, and firewall services.]
This script has been written to help keep an unattended OpenBSD box working as a firewall on a cable modem. The box gets its IP through DHCP, and as such this can change. When the IP changes, there have been problems with NAT and IPF -- so these are restarted/reconfigured. Since the DNS records must also be updated, when the IP changes this information is mailed to a sent admin address, so the machine is never "lost".

Whenever something else comes up that mucks up the machine, I add it to this script. So far so good, five months and counting.

WebDhcpDns is a Web interface for managing DHCP/DNS configuration on a network split into different VLANs.
WebDhcpDns manipulates isc-dhcpd3 and mydns configuration to assign machines to specific VLANs according to their MAC address.
It was made to allow administrators to delegate the DHCP/DNS configuration to temporary administrators without giving them direct access to the servers or the configuration files. LDAP authentication is also available.
WebDhcpDns program is licensed under the gpl GPL. Developed by Easter-eggs for the INHA.
Main features:
- Php/Mysql
- Use dhcpd 3 and mydns
- Ldap authentification possible
- IP and Vlan attribution depending on a machine mac address
- Vlans management delegation
- Configuration files for the dhcp server are automatically updated

DHCPsql projects implements the RFC2132 and at least RFC3046 as a dynamic configurable SQL-based DHCP server, based on the udhcpd code, extended to mask-and-select by client DHCP packets.
Targets:
- Discover, start with a working pre prototype, always send first ip in subnet
- Leases, SQL implementation should be done for storing and recieving leases. To send next free ip in subnet.
- Static leases, fixed leasetime
- Request, basics send ACK/NAK
- Webfrontend, initial frontend for viewing the database
Enhancements:
- This version of DHCPsql supports OPTION_LIST with OPTION_IP.
- This allows administrators to add multiple IP addresses to their DHCP options.
- This feature was lacking in the previous releases where only one IP address was allowed, and this limited the use of the nameserver field.

Net::DHCP::Packet is a Perl module with object methods to create a DHCP packet.

SYNOPSIS

use Net::DHCP::Packet;

my $p = new Net::DHCP::Packet->new(
Chaddr => 000BCDEF,
Xid => 0x9F0FD,
Ciaddr => 0.0.0.0,
Siaddr => 0.0.0.0,
Hops => 0);

Represents a DHCP packet as specified in RFC 1533, RFC 2132.

CONSTRUCTOR

This module only provides basic constructor. For "easy" constructors, you can use the Net::DHCP::Session module.

new( )

new( BUFFER )

new( ARG => VALUE, ARG => VALUE... )

Creates an Net::DHCP::Packet object, which can be used to send or receive DHCP network packets. BOOTP is not supported.

Without argument, a default empty packet is created.

$packet = Net::DHCP::Packet();

A BUFFER argument is interpreted as a binary buffer like one provided by the socket recv() function. if the packet is malformed, a fatal error is issued.

use IO::Socket::INET;
use Net::DHCP::Packet;

$sock = IO::Socket::INET->new(LocalPort => 67, Proto => "udp", Broadcast => 1)
or die "socket: $@";

while ($sock->recv($newmsg, 1024)) {
$packet = Net::DHCP::Packet->new($newmsg);
print $packet->toString();
}

To create a fresh new packet new() takes arguments as a key-value pairs :

ARGUMENT FIELD OCTETS DESCRIPTION
-------- ----- ------ -----------

Op op 1 Message op code / message type.
1 = BOOTREQUEST, 2 = BOOTREPLY
Htype htype 1 Hardware address type, see ARP section in "Assigned
Numbers" RFC; e.g., 1 = 10mb ethernet.
Hlen hlen 1 Hardware address length (e.g. 6 for 10mb
ethernet).
Hops hops 1 Client sets to zero, optionally used by relay agents
when booting via a relay agent.
Xid xid 4 Transaction ID, a random number chosen by the
client, used by the client and server to associate
messages and responses between a client and a
server.
Secs secs 2 Filled in by client, seconds elapsed since client
began address acquisition or renewal process.
Flags flags 2 Flags (see figure 2).
Ciaddr ciaddr 4 Client IP address; only filled in if client is in
BOUND, RENEW or REBINDING state and can respond
to ARP requests.
Yiaddr yiaddr 4 your (client) IP address.
Siaddr siaddr 4 IP address of next server to use in bootstrap;
returned in DHCPOFFER, DHCPACK by server.
Giaddr giaddr 4 Relay agent IP address, used in booting via a
relay agent.
Chaddr chaddr 16 Client hardware address.
Sname sname 64 Optional server host name, null terminated string.
File file 128 Boot file name, null terminated string; "generic"
name or null in DHCPDISCOVER, fully qualified
directory-path name in DHCPOFFER.
IsDhcp isDhcp 4 Controls whether the packet is BOOTP or DHCP.
DHCP conatains the "magic cookie" of 4 bytes.
0x63 0x82 0x53 0x63.
DHO_*code Optional parameters field. See the options
documents for a list of defined options.
See Net::DHCP::Constants.
Padding padding * Optional padding at the end of the packet

See below methods for values and syntax descrption.

Note: DHCP options are created in the same order as key-value pairs.

Dual DHCP DNS Server is a combined DHCP/DNS server for small LANs.
Dynamic DHCP allocates/renews host addresses, while the caching DNS server first tries resolving from DHCP-allotted names, then from cache, and only then forwarding to external DNS servers.
Dual DHCP DNS Server supports an optional static DHCP mode and static IPs, automatic dynamic DNS updates from DHCP, and the ability to co-exist with other DHCP servers.
It is self-configuring and doesnt require the creation of zone files, and uses little memory and CPU.
Enhancements:
- This release fixes zone replication bugs.