1 files changed, 58 insertions, 0 deletions
diff --git a/dhcpv6/dhcpv6.go b/dhcpv6/dhcpv6.go
index 0dabca5..9382334 100644
--- a/dhcpv6/dhcpv6.go
+++ b/dhcpv6/dhcpv6.go
@@ -1,8 +1,12 @@
 package dhcpv6
 
 import (
+	"errors"
 	"fmt"
 	"net"
+	"strings"
+
+	"github.com/insomniacslk/dhcp/iana"
 )
 
 type DHCPv6 interface {
@@ -199,3 +203,57 @@ func EncapsulateRelay(d DHCPv6, mType MessageType, linkAddr, peerAddr net.IP) (D
 	outer.AddOption(&orm)
 	return &outer, nil
 }
+
+// IsUsingUEFI function takes a DHCPv6 message and returns true if
+// the machine trying to netboot is using UEFI of false if it is not.
+func IsUsingUEFI(msg DHCPv6) bool {
+	// RFC 4578 says:
+	// As of the writing of this document, the following pre-boot
+	//    architecture types have been requested.
+	//             Type   Architecture Name
+	//             ----   -----------------
+	//               0    Intel x86PC
+	//               1    NEC/PC98
+	//               2    EFI Itanium
+	//               3    DEC Alpha
+	//               4    Arc x86
+	//               5    Intel Lean Client
+	//               6    EFI IA32
+	//               7    EFI BC
+	//               8    EFI Xscale
+	//               9    EFI x86-64
+	if opt := msg.GetOneOption(OptionClientArchType); opt != nil {
+		optat := opt.(*OptClientArchType)
+		for _, at := range optat.ArchTypes {
+			// TODO investigate if other types are appropriate
+			if at == iana.EFI_BC || at == iana.EFI_X86_64 {
+				return true
+			}
+		}
+	}
+	if opt := msg.GetOneOption(OptionUserClass); opt != nil {
+		optuc := opt.(*OptUserClass)
+		for _, uc := range optuc.UserClasses {
+			if strings.Contains(string(uc), "EFI") {
+				return true
+			}
+		}
+	}
+	return false
+}
+
+// GetTransactionID returns a transactionID of a message or its inner message
+// in case of relay
+func GetTransactionID(packet DHCPv6) (uint32, error) {
+	if message, ok := packet.(*DHCPv6Message); ok {
+		return message.TransactionID(), nil
+	}
+	if relay, ok := packet.(*DHCPv6Relay); ok {
+		message, err := relay.GetInnerMessage()
+		if err != nil {
+			return 0, err
+		}
+		return GetTransactionID(message)
+	}
+	return 0, errors.New("Invalid DHCPv6 packet")
+}