1 files changed, 57 insertions, 0 deletions
diff --git a/dhcpv4/option_ip_address_lease_time.go b/dhcpv4/option_ip_address_lease_time.go
new file mode 100644
index 0000000..7562c58
--- /dev/null
+++ b/dhcpv4/option_ip_address_lease_time.go
@@ -0,0 +1,57 @@
+package dhcpv4
+
+import (
+	"encoding/binary"
+	"fmt"
+)
+
+// This option implements the IP Address Lease Time option
+// https://tools.ietf.org/html/rfc2132
+
+// OptIPAddressLeaseTime represents the IP Address Lease Time option.
+type OptIPAddressLeaseTime struct {
+	LeaseTime uint32
+}
+
+// ParseOptIPAddressLeaseTime constructs an OptIPAddressLeaseTime struct from a
+// sequence of bytes and returns it, or an error.
+func ParseOptIPAddressLeaseTime(data []byte) (*OptIPAddressLeaseTime, error) {
+	// Should at least have code, length, and lease time.
+	if len(data) < 6 {
+		return nil, ErrShortByteStream
+	}
+	code := OptionCode(data[0])
+	if code != OptionIPAddressLeaseTime {
+		return nil, fmt.Errorf("expected option %v, got %v instead", OptionIPAddressLeaseTime, code)
+	}
+	length := int(data[1])
+	if length != 4 {
+		return nil, fmt.Errorf("expected length 4, got %v instead", length)
+	}
+	leaseTime := binary.BigEndian.Uint32(data[2:6])
+	return &OptIPAddressLeaseTime{LeaseTime: leaseTime}, nil
+}
+
+// Code returns the option code.
+func (o *OptIPAddressLeaseTime) Code() OptionCode {
+	return OptionIPAddressLeaseTime
+}
+
+// ToBytes returns a serialized stream of bytes for this option.
+func (o *OptIPAddressLeaseTime) ToBytes() []byte {
+	serializedTime := make([]byte, 4)
+	binary.BigEndian.PutUint32(serializedTime, o.LeaseTime)
+	serializedOpt := []byte{byte(o.Code()), byte(o.Length())}
+	return append(serializedOpt, serializedTime...)
+}
+
+// String returns a human-readable string for this option.
+func (o *OptIPAddressLeaseTime) String() string {
+	return fmt.Sprintf("IP Addresses Lease Time -> %v", o.LeaseTime)
+}
+
+// Length returns the length of the data portion (excluding option code and byte
+// for length, if any).
+func (o *OptIPAddressLeaseTime) Length() int {
+	return 4
+}