The MASM Forum Archive 2004 to 2012

Hi,

.386
.model flat,stdcall

;include \masm32\include\windows.inc
include \masm32\include\masm32rt.inc

include \masm32\include\advapi32.inc
includelib \masm32\lib\advapi32.lib

.data?
    hCSP DWORD ?

.data
    ;---------------------------------------------
    ; Cryptographic provider type
    ;
    MS_DEF_PROV BYTE "Microsoft Base Cryptographic Provider v1.0",0
    MS_ENHANCED_PROV BYTE "Microsoft Enhanced Cryptographic Provider v1.0",0

.code

start:
    push 0
    push dword ptr 24 ;PROV_RSA_FULL is already definied in windows.inc it seems (although it is actually in WinCrypt.h)
    push 0
    push offset MS_DEF_PROV
    push 0
    lea eax,hCSP
    push eax
    call CryptAcquireContext

    call GetLastError

    print str$(eax)

    push 0
    push hCSP
    call CryptReleaseContext

    ret

end start

According to http://msdn.microsoft.com/en-us/library/aa379886%28VS.85%29.aspx error NTE_BAD_PROV_TYPE( 0x80090014L ) is:

QuoteThe value of the dwProvType parameter is out of range. All provider types must be from 1 through 999, inclusive.

What the hell am I missing????  :red  I tried everything I can think of - no go. Note I am testing this in XP Mode - I have already found it doesn't like some things in there.

Best regards,
Robin.

Quote    push 0   ; dwFlags
    push dword ptr 24    ; PROV_RSA_FULL is already NOT defined in windows.inc it seems (although it is actually in WinCrypt.h)
    push 0   ; pszProvider
    push offset MS_DEF_PROV
    push 0   ; pszContainer
;    lea eax,hCSP
;    push eax
    push offset hCSP
    call CryptAcquireContext

    call GetLastError
    print LastError$()

Invalid provider, in genuine XP.

MS Enhanced Provider (MS_ENHANCED_PROV) IS a valid provider........ ???????  :dazzled:

http://msdn.microsoft.com/en-us/library/aa386986%28VS.85%29.aspx

So AES is now part of the Base provider? Note I'm not (knowingly) running the export version of XP with restricted crypto.

The following works:

    push CRYPT_VERIFY_CONTEXT
    push PROV_RSA_AES
    push 0
    push 0
    push offset hCSP
    call CryptAcquireContext


EDIT: http://msdn.microsoft.com/en-us/library/aa386979%28VS.85%29.aspx

Hmmmm - seems it auto-selects a suitable provider?? The docs say it just uses the default provider though if none is named, and not to use the default as export restrictions change over time and so the default may not be suitable.

Very confused,
Robin.

Hi,

On XP SP3, the provider type to use to get the Microsoft AES Cryptographic Provider is:

Provider BYTE "Microsoft Enhanced RSA and AES Cryptographic Provider (Prototype)",0

On Vista/Win 7 the provider to use is:

Provider BYTE "Microsoft Enhanced RSA and AES Cryptographic Provider",0

Best regards,
Robin.