GetMACAddress

S

samp

I'm trying to get the number from my network card using this function,
it is only returning
00 00 00 00 00 00

what would it be?





Option Explicit
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
' Copyright ©1996-2009 VBnet, Randy Birch, All Rights Reserved.
' Some pages may also contain other copyrights by the author.
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
' Distribution: You can freely use this code in your own
' applications, but you may not reproduce
' or publish this code on any web site,
' online service, or distribute as source
' on any media without express permission.
''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
Private Const NCBASTAT As Long = &H33
Private Const NCBNAMSZ As Long = 16
Private Const HEAP_ZERO_MEMORY As Long = &H8
Private Const HEAP_GENERATE_EXCEPTIONS As Long = &H4
Private Const NCBRESET As Long = &H32

Private Type NET_CONTROL_BLOCK 'NCB
ncb_command As Byte
ncb_retcode As Byte
ncb_lsn As Byte
ncb_num As Byte
ncb_buffer As Long
ncb_length As Integer
ncb_callname As String * NCBNAMSZ
ncb_name As String * NCBNAMSZ
ncb_rto As Byte
ncb_sto As Byte
ncb_post As Long
ncb_lana_num As Byte
ncb_cmd_cplt As Byte
ncb_reserve(9) As Byte 'Reserved, must be 0
ncb_event As Long
End Type

Private Type ADAPTER_STATUS
adapter_address(5) As Byte
rev_major As Byte
reserved0 As Byte
adapter_type As Byte
rev_minor As Byte
duration As Integer
frmr_recv As Integer
frmr_xmit As Integer
iframe_recv_err As Integer
xmit_aborts As Integer
xmit_success As Long
recv_success As Long
iframe_xmit_err As Integer
recv_buff_unavail As Integer
t1_timeouts As Integer
ti_timeouts As Integer
Reserved1 As Long
free_ncbs As Integer
max_cfg_ncbs As Integer
max_ncbs As Integer
xmit_buf_unavail As Integer
max_dgram_size As Integer
pending_sess As Integer
max_cfg_sess As Integer
max_sess As Integer
max_sess_pkt_size As Integer
name_count As Integer
End Type

Private Type NAME_BUFFER
name As String * NCBNAMSZ
name_num As Integer
name_flags As Integer
End Type

Private Type ASTAT
adapt As ADAPTER_STATUS
NameBuff(30) As NAME_BUFFER
End Type

Private Declare Function Netbios Lib "netapi32" _
(pncb As NET_CONTROL_BLOCK) As Byte

Private Declare Sub CopyMemory Lib "kernel32" _
Alias "RtlMoveMemory" _
(hpvDest As Any, ByVal _
hpvSource As Long, ByVal _
cbCopy As Long)

Private Declare Function GetProcessHeap Lib "kernel32" () As Long

Private Declare Function HeapAlloc Lib "kernel32" _
(ByVal hHeap As Long, _
ByVal dwFlags As Long, _
ByVal dwBytes As Long) As Long

Private Declare Function HeapFree Lib "kernel32" _
(ByVal hHeap As Long, _
ByVal dwFlags As Long, _
lpMem As Any) As Long





Private Function GetMACAddress(sDelimiter As String) As String

'retrieve the MAC Address for the network controller
'installed, returning a formatted string

Dim tmp As String
Dim pASTAT As Long
Dim NCB As NET_CONTROL_BLOCK
Dim AST As ASTAT
Dim cnt As Long

'The IBM NetBIOS 3.0 specifications defines four basic
'NetBIOS environments under the NCBRESET command. Win32
'follows the OS/2 Dynamic Link Routine (DLR) environment.
'This means that the first NCB issued by an application
'must be a NCBRESET, with the exception of NCBENUM.
'The Windows NT implementation differs from the IBM
'NetBIOS 3.0 specifications in the NCB_CALLNAME field.
NCB.ncb_command = NCBRESET
Call Netbios(NCB)

'To get the Media Access Control (MAC) address for an
'ethernet adapter programmatically, use the Netbios()
'NCBASTAT command and provide a "*" as the name in the
'NCB.ncb_CallName field (in a 16-chr string).
NCB.ncb_callname = "* "
NCB.ncb_command = NCBASTAT

'For machines with multiple network adapters you need to
'enumerate the LANA numbers and perform the NCBASTAT
'command on each. Even when you have a single network
'adapter, it is a good idea to enumerate valid LANA numbers
'first and perform the NCBASTAT on one of the valid LANA
'numbers. It is considered bad programming to hardcode the
'LANA number to 0 (see the comments section below).
NCB.ncb_lana_num = 0
NCB.ncb_length = Len(AST)

pASTAT = HeapAlloc(GetProcessHeap(), _
HEAP_GENERATE_EXCEPTIONS Or _
HEAP_ZERO_MEMORY, _
NCB.ncb_length)

If pASTAT <> 0 Then

NCB.ncb_buffer = pASTAT
Call Netbios(NCB)

CopyMemory AST, NCB.ncb_buffer, Len(AST)

'convert the byte array to a string
GetMACAddress = MakeMacAddress(AST.adapt.adapter_address(),
sDelimiter)

HeapFree GetProcessHeap(), 0, pASTAT

Else
Debug.Print "memory allocation failed!"
Exit Function
End If

End Function


Private Function MakeMacAddress(b() As Byte, sDelim As String) As
String

Dim cnt As Long
Dim buff As String

On Local Error GoTo MakeMac_error

'so far, MAC addresses are
'exactly 6 segments in size (0-5)
If UBound(b) = 5 Then

'concatenate the first five values
'together and separate with the
'delimiter char
For cnt = 0 To 4
buff = buff & Right$("00" & Hex(b(cnt)), 2) & sDelim
Next

'and append the last value
buff = buff & Right$("00" & Hex(b(5)), 2)

End If 'UBound(b)

MakeMacAddress = buff

MakeMac_exit:
Exit Function

MakeMac_error:
MakeMacAddress = "(error building MAC address)"
Resume MakeMac_exit

End Function
 

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