The qDHCPv4 server

qDHCPv4 is DHCPv4 server for public places that use unmanaged switches.

Features

• Dynamically assigned lease time based on schedule (time points when all users must free or extend their lease). Useful for preventing exhaustion of free leases on public places.
• User Classes / Subnets based on Host Name (DHCP Option #12).

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• Full High Super+ Speed (as USB). Generate 41 Mbps offer / ACK flood by incoming 74 Mbps Discover / Request flood.
• Goes beyond the RFC scope. You can see clear logic in one of first commits.
• Need only 34 GiB virtual memory to run (on 64bit systems).
• Doesn't require permanent data storage.
• Code-style: JavaScript <-> Go <-> C.

Usage

For Windows 64bit download, unpack and run:

qDHCPv4.exe -conf=<path to config.json>

For other systems: compile binary go get go build.

Documentation

LeaseEndTime scheduler logic

LeaseEndTime 3 user example

Config file

See example_config.json.

globalOptions

Transmitted options to DHCP client. List of all options and descriptions: dhcpd options, DHCP and BOOTP parameters, dhcpd options RU, DHCP options in JSON. Example:

"globalOptions":{
	"ServerIdentifier": "194.188.64.28",
	"SubnetMask": "255.255.0.0",
	"Router": ["194.188.64.8"],
	"DomainNameServer": ["194.188.64.8"]
	}

leaseEndTime

Time when all clients must renew the lease. Format hh:mm. Example:

"leaseEndTime":[
	"11:35",
    "12:50",
    "17:23"
]

devices

Define user Classes / Subnets based on first two chars from Host Name (DHCP Option #12). Parameters:

• name - first two chars from Host Name (android-a70378b9bf61c919 -> an; iPhone-Jon, iPad-Jon -> iP; Windows-Phone -> Wi)
• startIP - first client IP in this scope (Class / Subnet)
• rangeIP - count of all IP's in this scope (Class / Subnet) Example:

"devices":[
	{"name": "an", "startIP": "194.188.36.1", "rangeIP": 1024},
    {"name": "iP", "startIP": "194.188.40.1", "rangeIP": 1024},
    {"name": "Wi", "startIP": "194.188.44.1", "rangeIP": 1024}
]

defaultDevice

startIP and rangeIP for all other devices.

"defaultDevice":{"startIP": "194.188.32.1", "rangeIP": 1024}