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stefan_schnell
Active Contributor
With the random number generator offers Intel a powerful possibility to use a secure way to create random numbers on a hardware base. You can find more information here. Unfortunately it is not direct possible to use this kind of code inside of ABAP. I presented here an example how to use ANSI C inside ABAP. On the same way it is possible to use assembler code inside ABAP. Here an example how to use the RDRAND instruction inside ABAP via FBSLs assembler layer.

At first we check the availability via CPUID instruction. If it is successful, we call the instruction via the opcodes. To receive the text of OutputDebugString use DebugView.

We begin with the assembler include:
;-Begin-----------------------------------------------------------------

.data
@FeatureFlagsECX dd 0
@RandomNumber dd 0
@NumberFormat db "%ld",0
@strNumber db 20 dup 0
@msgRDRAND db "Random number generator on-chip",0

.code
enter 0, 0

;-Checks the availability of CPUID instruction----------------------
pushfd
pop eax
mov ebx, eax
xor eax, &H00200000
push eax
popfd
pushfd
pop eax

;-If CPUID is available---------------------------------------------
.if eax <> ebx

;-Feature information-------------------------------------------
mov eax, 1
cpuid
mov [FeatureFlagsECX], ecx

clc
bt [FeatureFlagsECX], 30
jnc Next
invoke OutputDebugString, msgRDRAND

;-rdrand eax as opcodes-------------------------------------
db &H0F, &HC7, &HF0
jnc Next
mov [RandomNumber], eax
;-Convert number to string--------------------------------
invoke wsprintf, strNumber, NumberFormat, [RandomNumber]
invoke OutputDebugString, strNumber

@Next

.endif

mov eax, [RandomNumber]
leave
ret

;-End-------------------------------------------------------------------

Here the ABAP report:
"-Begin-----------------------------------------------------------------
Program ZASSEMBLER.

"-Constants---------------------------------------------------------
Constants SW_SHOWNORMAL Type i Value 1.

"-Variables---------------------------------------------------------
Data oScriptX Type OLE2_OBJECT.
Data Buffer Type String Value ''.
Data WorkDir Type String Value ''.
Data WinInc Type String Value ''.
Data FileName Type String Value ''.
Data rc Type i Value 0.
Data hFileMap Type i Value 0.
Data ProcID Type i Value 0.
Data InclCode Type String Value ''.
Data FBSLFileName Type String Value 'RandomNumber.fbs'.
Data rcRandomNumber Type String Value ''.
Data RandomNumber Type i Value 0.

"-Macros------------------------------------------------------------
Define _.
Concatenate Buffer &1 cl_abap_char_utilities=>cr_lf Into Buffer.
End-Of-Definition.

Define Flush.
Call Function 'AC_SYSTEM_FLUSH' Exceptions Others = 1.
End-Of-Definition.

"-Main--------------------------------------------------------------
Create Object oScriptX 'ScriptX'.
If sy-subrc <> 0 Or oScriptX-Handle = 0 Or oScriptX-Type <> 'OLE2'.
Call Function 'ZSCRIPTXDLL'.
Create Object oScriptX 'ScriptX'.
EndIf.

If sy-subrc = 0 And oScriptX-Handle > 0 And oScriptX-Type = 'OLE2'.

"-Show messages in system debugger, e.g. DebugView--------------
Set Property Of oScriptX 'DebugOutput' = 1.

"-Get SAP GUIs work directory-----------------------------------
Call Method cl_gui_frontend_services=>get_sapgui_workdir
Changing SAPWORKDIR = WorkDir Exceptions Others = 1.
Set Property Of oScriptX 'CurrentDirectory' = WorkDir.

Concatenate '#Include "' WorkDir '\Include\Windows.inc"'
Into WinInc.

Call Method Of oScriptX 'ExtractFbslExe'.

Call Method Of oScriptX 'ExtractFbslWinInc'.

Call Method Of oScriptX 'FileMapCreate' = hFileMap
Exporting #1 = 'SAP001' #2 = 32.

If hFileMap <> 0.

"-FBSL script begin-----------------------------------------------------

"-Directives----------------------------------------------------------
_ '#AppType GUI'.
_ '#Option Strict'.
_ WinInc.

"-Function Assembler--------------------------------------------------
_ 'DynAsm RandomNumber() As Long'.

"-Read Assembler code from include file-----------------------------
Call Function 'ZREADINCLASSTRING'
Exporting I_InclName = 'ZASM_INC'
Importing E_strIncl = InclCode.
_ InclCode.

_ 'End DynAsm'.

"-Sub RC--------------------------------------------------------------
_ 'Sub RC(ByVal FileMapName As String, ByVal RetCode As String)'.
_ ' Dim hMMF As Long'.
_ ' Dim Buffer As Long'.
_ ' Dim Temp As String'.
_ ' hMMF = OpenFileMapping(FILE_MAP_ALL_ACCESS, 0, FileMapName)'.
_ ' If hMMF Then'.
_ ' Buffer = MapViewOfFile(hMMF, FILE_MAP_ALL_ACCESS, 0, 0, 0)'.
_ ' If Buffer Then'.
_ ' Poke(Buffer, RetCode)'.
_ ' UnmapViewOffile(Buffer)'.
_ ' End If'.
_ ' CloseHandle(hMMF)'.
_ ' End If'.
_ 'End Sub'.

"-Main----------------------------------------------------------------
_ 'Sub Main()'.
_ ' RC("SAP001", RandomNumber())'.
_ 'End Sub'.

"-FBSL script end-------------------------------------------------------

Concatenate WorkDir '\' FBSLFileName Into FileName.
Call Method Of oScriptX 'WriteFile' Exporting #1 = FileName
#2 = Buffer.
Flush.

Concatenate '"' FileName '"' Into FileName.
Call Method Of oScriptX 'Shell' = ProcID Exporting
#1 = 'Fbsl.exe' #2 = FileName
#3 = SW_SHOWNORMAL #4 = 1.
Flush.
Replace All Occurrences Of '"' In FileName With ''.

Call Method Of oScriptX 'FileMapRead' = rcRandomNumber
Exporting #1 = 'SAP001' #2 = 32.
Flush.

"-Delete files------------------------------------------------
Call Method Of oScriptX 'DeleteFileA'
Exporting #1 = FileName.

Call Method Of oScriptX 'DeleteFileA'
Exporting #1 = 'Fbsl.exe'.
Call Method Of oScriptX 'DeleteDirectory'
Exporting #1 = 'Include'.
Flush.

RandomNumber = rcRandomNumber.
Write: / RandomNumber.

Call Method Of oScriptX 'FileMapClose' = rc
Exporting #1 = hFileMap.
Flush.

EndIf.

Free Object oScriptX.
EndIf.

"-End-------------------------------------------------------------------

As you can see it is possible to use Intel-style assembler code inside ABAP. In my case I need the CPU functions for doument management, here for creating (security) keys, AES chiffres and CRC checks,
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