1 files changed, 83 insertions, 0 deletions
diff --git a/dhcpv6/dhcpv6.go b/dhcpv6/dhcpv6.go
index 0dabca5..adc52c5 100644
--- a/dhcpv6/dhcpv6.go
+++ b/dhcpv6/dhcpv6.go
@@ -1,8 +1,10 @@
 package dhcpv6
 
 import (
+	"errors"
 	"fmt"
 	"net"
+	"strings"
 )
 
 type DHCPv6 interface {
@@ -199,3 +201,84 @@ func EncapsulateRelay(d DHCPv6, mType MessageType, linkAddr, peerAddr net.IP) (D
 	outer.AddOption(&orm)
 	return &outer, nil
 }
+
+// IsNetboot function takes a DHCPv6 message and returns true if the machine
+// is trying to netboot. It checks if "boot file" is one of the requested
+// options, which is useful for SOLICIT/REQUEST packet types, it also checks
+// if the "boot file" option is included in the packet, which is useful for
+// ADVERTISE/REPLY packet.
+func IsNetboot(msg DHCPv6) bool {
+	if IsOptionRequested(msg, OptionBootfileURL) {
+		return true
+	}
+	if optbf := msg.GetOneOption(OptionBootfileURL); optbf != nil {
+		return true
+	}
+	return false
+}
+
+// IsOptionRequested function takes a DHCPv6 message and an OptionCode, and
+// returns true if that option is within the requested options of the DHCPv6
+// message.
+func IsOptionRequested(msg DHCPv6, requested OptionCode) bool {
+	for _, optoro := range msg.GetOption(OptionORO) {
+		for _, o := range optoro.(*OptRequestedOption).RequestedOptions() {
+			if o == requested {
+				return true
+			}
+		}
+	}
+	return false
+}
+
+// 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)
+		// TODO investigate if other types are appropriate
+		if optat.ArchType == EFI_BC || optat.ArchType == 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")
+}