README
¶
dhcp4
Package dhcp4 is an IPv4 DHCP library as described in RFC 2131, 2132, and
3396.
It implements encoding and decoding of DHCP messages in dhcp4. Option parsing
is in the dhcp4opts package; a simple client is included in dhcp4client.
Some day, there may be a server.
If you are already using another IPv4 DHCP library like
krolaw's, you can still use dhcp4opts to
decode options not implemented in krolaw's DHCP library.
Documentation
¶
Overview ¶
Package dhcp4 implements constants and marshaling for IPv4 DHCP packets as described by RFC 2131, RFC 2132, and RFC 3396.
Index ¶
Constants ¶
This section is empty.
Variables ¶
var ( // ErrInvalidOptions is returned when invalid options data is // encountered during parsing. The data could report an incorrect // length or have trailing bytes which are not part of the option. ErrInvalidOptions = errors.New("invalid options data") // ErrInvalidPacket is returned when a byte slice does not contain // enough data to create a valid Packet. ErrInvalidPacket = errors.New("not enough bytes for valid packet") // ErrOptionNotPresent is returned when a requested opcode is not in // the packet. ErrOptionNotPresent = errors.New("option code not present in packet") )
Functions ¶
This section is empty.
Types ¶
type OpCode ¶
type OpCode uint8
OpCode is the BOOTP message type as defined by RFC 2131, Section 2.
Note that the DHCP message type is embedded via OptionDHCPMessageType.
Legal op codes as defined by RFC 2131, Section 2.
type OptionCode ¶
type OptionCode uint8
OptionCode is a DHCP option code as defined by RFC 2132.
const ( End OptionCode = 255 Pad OptionCode = 0 OptionSubnetMask OptionCode = 1 OptionTimeOffset OptionCode = 2 OptionRouters OptionCode = 3 OptionTimeServers OptionCode = 4 OptionNameServers OptionCode = 5 OptionDomainNameServers OptionCode = 6 OptionLogServers OptionCode = 7 OptionCookieServers OptionCode = 8 OptionLPRServers OptionCode = 9 OptionImpressServers OptionCode = 10 OptionResourceLocationServers OptionCode = 11 OptionHostName OptionCode = 12 OptionBootFileSize OptionCode = 13 OptionMeritDumpFile OptionCode = 14 OptionDomainName OptionCode = 15 OptionSwapServer OptionCode = 16 OptionRootPath OptionCode = 17 OptionExtensionsPath OptionCode = 18 OptionIPForwardingEnableDisable OptionCode = 19 OptionNonLocalSourceRoutingEnableDisable OptionCode = 20 OptionPolicyFilter OptionCode = 21 OptionMaximumDatagramReassemblySize OptionCode = 22 OptionDefaultIPTimeToLive OptionCode = 23 OptionPathMTUAgingTimeout OptionCode = 24 OptionPathMTUPlateauTable OptionCode = 25 OptionInterfaceMTU OptionCode = 26 OptionAllSubnetsAreLocal OptionCode = 27 OptionBroadcastAddress OptionCode = 28 OptionPerformMaskDiscovery OptionCode = 29 OptionMaskSupplier OptionCode = 30 OptionPerformRouterDiscovery OptionCode = 31 OptionRouterSolicitationAddress OptionCode = 32 OptionStaticRoute OptionCode = 33 OptionTrailerEncapsulation OptionCode = 34 OptionARPCacheTimeout OptionCode = 35 OptionEthernetEncapsulation OptionCode = 36 OptionTCPDefaultTTL OptionCode = 37 OptionTCPKeepaliveInterval OptionCode = 38 OptionTCPKeepaliveGarbage OptionCode = 39 OptionNetworkInformationServiceDomain OptionCode = 40 OptionNetworkInformationServers OptionCode = 41 OptionNetworkTimeProtocolServers OptionCode = 42 OptionVendorSpecificInformation OptionCode = 43 OptionNetBIOSOverTCPIPNameServer OptionCode = 44 OptionNetBIOSOverTCPIPDatagramDistributionServer OptionCode = 45 OptionNetBIOSOverTCPIPNodeType OptionCode = 46 OptionNetBIOSOverTCPIPScope OptionCode = 47 OptionXWindowSystemFontServer OptionCode = 48 OptionXWindowSystemDisplayManager OptionCode = 49 // DHCP extensions. OptionRequestedIPAddress OptionCode = 50 OptionIPAddressLeaseTime OptionCode = 51 OptionOverload OptionCode = 52 OptionDHCPMessageType OptionCode = 53 OptionServerIdentifier OptionCode = 54 OptionParameterRequestList OptionCode = 55 OptionMessage OptionCode = 56 OptionMaximumDHCPMessageSize OptionCode = 57 OptionRenewalTimeValue OptionCode = 58 OptionRebindingTimeValue OptionCode = 59 OptionVendorClassIdentifier OptionCode = 60 OptionClientIdentifier OptionCode = 61 OptionTFTPServerName OptionCode = 66 OptionBootFileName OptionCode = 67 )
Option codes defined by RFC 2132. (Incomplete)
type Options ¶
type Options map[OptionCode][]byte
Options is a map of OptionCode keys with a slice of byte values.
Its methods can be used to easily check for additional information from a packet. Get should be used to access data from Options.
func (Options) Add ¶
func (o Options) Add(key OptionCode, value encoding.BinaryMarshaler) error
Add adds a new OptionCode key and BinaryMarshaler's bytes to the Options map.
func (Options) AddRaw ¶
func (o Options) AddRaw(key OptionCode, value []byte)
AddRaw adds a new OptionCode key and raw value byte slice to the Options map.
func (Options) Get ¶
func (o Options) Get(key OptionCode) []byte
Get attempts to retrieve the value specified by an OptionCode key.
If a value is found, get returns a non-nil byte slice. If it is not found, Get returns nil.
type Packet ¶
type Packet struct {
// Op is the BOOTP message op code / message type.
//
// This is not to be confused with the DHCP message type, which is
// defined as an option value.
Op OpCode
// HType is the hardware type.
//
// The possible values are listed in the IANA ARP assigned numbers.
HType uint8
// Hops is the number of hops this packet has taken.
Hops uint8
// TransactionID is a random number used to associate server responses
// with client requests.
TransactionID [4]byte
// Secs is the number of seconds elapsed since the client began address
// acquisition or renewal process.
Secs uint16
// Broadcast is the broadcast flag of the flags field.
Broadcast bool
// Client IP address.
CIAddr net.IP
// Your IP address.
YIAddr net.IP
// Server IP address.
SIAddr net.IP
// Gateway IP address.
GIAddr net.IP
// Client hardware address.
CHAddr net.HardwareAddr
// ServerName is an optional server host name.
ServerName string
// BootFile is a fully qualified directory path to the boot file.
BootFile string
// Options is the list of vendor-specific extensions.
Options Options
}
Packet is a DHCPv4 packet as described in RFC 2131, Section 2.
func ParsePacket ¶
ParsePacket parses a DHCP4 packet from q.
func (*Packet) MarshalBinary ¶
MarshalBinary writes the packet to binary.
func (*Packet) UnmarshalBinary ¶
UnmarshalBinary reads the packet from binary.
Source Files
Directories
¶
| Path | Synopsis |
|---|---|
|
cmd
|
|
|
Package dhcp4client is a small, minimum-functionality client for DHCPv4.
|
Package dhcp4client is a small, minimum-functionality client for DHCPv4. |
|
Package dhcp4opts implements Options parsing for DHCPv4 options as described in RFC 2132.
|
Package dhcp4opts implements Options parsing for DHCPv4 options as described in RFC 2132. |