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/*++
Copyright (c) 1997 Microsoft Corporation
Module Name:
icrypt.hxx
Abstract:
C++ wrappers around the IISCrypto APIs.
This module contains the declarations for one base class and three derived classes:
IIS_CRYPTO_BASE | +--- IIS_CRYPTO_STORAGE | +--- IIS_CRYPTO_EXCHANGE_BASE | +--- IIS_CRYPTO_EXCHANGE_CLIENT | +--- IIS_CRYPTO_EXCHANGE_SERVER
IIS_CRYPTO_BASE is a general base class, containing the crypto provider handle, as well as the key exchange and signature handles. This class also provides a couple of member functions used by the derived classes.
IIS_CRYPTO_STORAGE is used by applications that need to store or transfer data in a secure manner. This class provides services for data encryption and descryption.
IIS_CRYPTO_EXCHANGE_BASE is a general base class for the key exchange classes.
IIS_CRYPTO_EXCHANGE_CLIENT is used by the client (i.e. sending) side of the multi-phase key exchange protocol.
IIS_CRYPTO_EXCHANGE_SERVER is used by the server (i.e. receiving) side of the multi-phase key exchange protocol.
The multi-phase key exchange protocol consists of the following steps:
Phase 1 (client.1):
1. Export public key exchange and signature blobs. 2. Send blobs to server.
Phase 2 (server.1):
1. Import client's public key exchange and signature blobs. 2. Export public key exchange and signature blobs. 3. Send blobs to client. 4. Generate random session key (call it Ka). 5. Encrypt session key with client's key exchange key. 6. Send encrypted session key to client.
Phase 3 (client.2):
1. Import server's public key exchange and signature blobs. 2. Import encrypted session key. 3. Generate random session key (call it Kb). 4. Encrypt session key with server's key exchange key. 5. Send encrypted session key to server. 6. Generate hash containing Ka, Kb, and string "Phase 3". 7. Send hash to the server.
Phase 4 (server.2):
1. Import encrypted session key. 2. Validate client's hash. 3. Generate hash containing Kb and string "Phase 4". 4. Send hash to the client.
Phase 5 (client.3):
1. Validate server's hash.
The end result is that each side has two session keys: one for sending encrypted data, one for receiving encrypted data. Each of these keys is represented by a IIS_CRYPTO_STORAGE class.
A few notes about the Win32 crypto APIs, IE4, and impersonating threads...
IE4 has changed the relationship between crypto key containers and security context. In the pre-IE4 days, whenever an application acquired a crypto context, the crypto APIs opened the necessary registry keys and kept them open until the context was released. With IE4 installed (actually this is an issue with the Protected Storage service that's installed with IE4) the crypto container registry keys are NOT opened when the context is aquired, they are are opened on demand when they're first needed. This causes much grief for us, as we may acquire the crypto context in one security context then try to import/whatever in another security context.
The hack (er, solution) implemented in these classes is to try the import/whatever operation in the current security context. If that operation fails and the current thread has an impersonation token, then we "revert to self" and retry the operation.
This solution has the blessing of the NT crypto team (specifically, Jeff Spelman).
Author:
Keith Moore (keithmo) 02-Dec-1996
Revision History:
--*/
#ifndef _ICRYPT_HXX_
#define _ICRYPT_HXX_
//
// Get the IIS Crypto stuff.
//
#include <iiscrypt.h>
//
// The base crypto class. This class contains the provider handle
// and the public (key exchange & signature) handles. This is intended
// as a base class for IIS_CRYPTO_STORAGE and IIS_CRYPTO_EXCHANGE_BASE.
//
class IIS_CRYPTO_BASE {
public:
//
// Constructor/destructor.
//
IIS_CRYPTO_BASE(); ~IIS_CRYPTO_BASE();
//
// Static method to open a crypto container by name. This method
// performs all of the games necessary to open a container, even
// if we're running in an impersonated security context.
//
static HRESULT GetCryptoContainerByName( OUT HCRYPTPROV * phProv, IN LPTSTR pszContainerName, IN DWORD dwAdditionalFlags, IN BOOL fApplyAcl );
//
// Initialize the crypto context.
//
HRESULT Initialize( IN HCRYPTPROV hProv = CRYPT_NULL, IN HCRYPTKEY hKeyExchangeKey = CRYPT_NULL, IN HCRYPTKEY hSignatureKey = CRYPT_NULL, IN BOOL fUseMachineKeyset = FALSE );
HRESULT Initialize2( IN HCRYPTPROV hProv = CRYPT_NULL );
//
// Query the key exchange key as a public key blob.
//
HRESULT GetKeyExchangeKeyBlob( OUT PIIS_CRYPTO_BLOB * ppKeyExchangeKeyBlob );
//
// Query the signature key as a public key blob.
//
HRESULT GetSignatureKeyBlob( OUT PIIS_CRYPTO_BLOB * ppSignatureKeyBlob );
//
// Accessors.
//
HCRYPTPROV QueryProviderHandle() { return m_hProv; }
protected:
//
// A handle to a crypto service provider.
//
HCRYPTPROV m_hProv; BOOL m_fCloseProv;
//
// A handle to our key exchange key.
//
HCRYPTKEY m_hKeyExchangeKey;
//
// A handle to our signature key.
//
HCRYPTKEY m_hSignatureKey;
#if DBG
//
// Validate object state.
//
BOOL ValidateState();
BOOL ValidateState2();
#endif
//
// Wrappers around the corresponding IISCryptoXxx() routines that
// Do The Right Thing when the current thread has an impersonation
// token.
//
static HRESULT SafeImportSessionKeyBlob( OUT HCRYPTKEY * phSessionKey, IN PIIS_CRYPTO_BLOB pSessionKeyBlob, IN HCRYPTPROV hProv, IN HCRYPTKEY hSignatureKey );
static HRESULT SafeImportSessionKeyBlob2( OUT HCRYPTKEY * phSessionKey, IN PIIS_CRYPTO_BLOB pSessionKeyBlob, IN HCRYPTPROV hProv, IN LPSTR pszPasswd );
static HRESULT SafeExportSessionKeyBlob( OUT PIIS_CRYPTO_BLOB * ppSessionKeyBlob, IN HCRYPTPROV hProv, IN HCRYPTKEY hSessionKey, IN HCRYPTKEY hKeyExchangeKey );
static HRESULT SafeExportSessionKeyBlob2( OUT PIIS_CRYPTO_BLOB * ppSessionKeyBlob, IN HCRYPTPROV hProv, IN HCRYPTKEY hSessionKey, IN LPSTR pszPasswd );
static HRESULT SafeEncryptDataBlob( OUT PIIS_CRYPTO_BLOB * ppDataBlob, IN PVOID pBuffer, IN DWORD dwBufferLength, IN DWORD dwRegType, IN HCRYPTPROV hProv, IN HCRYPTKEY hSessionKey );
static HRESULT SafeEncryptDataBlob2( OUT PIIS_CRYPTO_BLOB * ppDataBlob, IN PVOID pBuffer, IN DWORD dwBufferLength, IN DWORD dwRegType, IN HCRYPTPROV hProv, IN HCRYPTKEY hSessionKey );
//
// Thread token manipulators.
//
static HRESULT GetThreadImpersonationToken( OUT HANDLE * Token );
static HRESULT SetThreadImpersonationToken( IN HANDLE Token );
static BOOL AmIRunningInTheLocalSystemContext( VOID );
}; // IIS_CRYPTO_BASE
class IIS_CRYPTO_STORAGE : public IIS_CRYPTO_BASE {
public:
//
// Constructor/destructor.
//
IIS_CRYPTO_STORAGE(); ~IIS_CRYPTO_STORAGE();
//
// Initialize the crypto context, generating a new (random) session
// key.
//
HRESULT Initialize( IN BOOL fUseMachineKeyset = FALSE, IN HCRYPTPROV hProv = CRYPT_NULL );
//
// Initialize the crypto context, importing the session key from the
// given session key blob.
//
HRESULT Initialize( IN PIIS_CRYPTO_BLOB pSessionKeyBlob, IN BOOL fUseMachineKeyset = FALSE, IN HCRYPTPROV hProv = CRYPT_NULL );
//
// Initialize the crypto context, using pre-created provider,
// session, key exchange, and signature keys.
//
HRESULT Initialize( IN HCRYPTPROV hProv, IN HCRYPTKEY hSessionKey, IN HCRYPTKEY hKeyExchangeKey, IN HCRYPTKEY hSignatureKey, IN BOOL fUseMachineKeyset = FALSE );
//
// Query the session key as a session key blob.
//
HRESULT GetSessionKeyBlob( OUT PIIS_CRYPTO_BLOB * ppSessionKeyBlob );
//
// Encrypt data into a data blob.
//
virtual HRESULT EncryptData( OUT PIIS_CRYPTO_BLOB * ppDataBlob, IN PVOID pBuffer, IN DWORD dwBufferLength, IN DWORD dwRegType );
//
// Decrypt data from a data blob.
//
virtual HRESULT DecryptData( OUT PVOID * ppBuffer, OUT LPDWORD pdwBufferLength, OUT LPDWORD pdwRegType, IN PIIS_CRYPTO_BLOB pDataBlob );
protected:
//
// A handle to the session key.
//
HCRYPTKEY m_hSessionKey;
#if DBG
//
// Validate object state.
//
virtual BOOL ValidateState();
#endif
}; // IIS_CRYPTO_STORAGE
class IIS_CRYPTO_STORAGE2 : public IIS_CRYPTO_STORAGE {
public:
//
// Constructor/destructor.
//
IIS_CRYPTO_STORAGE2(){} ~IIS_CRYPTO_STORAGE2(){}
//
// Initialize the crypto context, generating a new (random) session
// key.
//
HRESULT Initialize( IN HCRYPTPROV hProv = CRYPT_NULL );
//
// Initialize the crypto context, importing the session key from the
// given session key blob.
//
HRESULT Initialize( IN PIIS_CRYPTO_BLOB pSessionKeyBlob, IN LPSTR pszPasswd, IN HCRYPTPROV hProv = CRYPT_NULL );
HRESULT GetSessionKeyBlob( IN LPSTR pszPasswd, OUT PIIS_CRYPTO_BLOB * ppSessionKeyBlob );
//
// Encrypt data into a data blob.
//
HRESULT EncryptData( OUT PIIS_CRYPTO_BLOB * ppDataBlob, IN PVOID pBuffer, IN DWORD dwBufferLength, IN DWORD dwRegType );
//
// Decrypt data from a data blob.
//
HRESULT DecryptData( OUT PVOID * ppBuffer, OUT LPDWORD pdwBufferLength, OUT LPDWORD pdwRegType, IN PIIS_CRYPTO_BLOB pDataBlob );
#if DBG
//
// Validate object state.
//
BOOL ValidateState();
#endif
}; // IIS_CRYPTO_STORAGE
class IIS_CRYPTO_EXCHANGE_BASE : public IIS_CRYPTO_BASE {
public:
//
// Constructor/destructor.
//
IIS_CRYPTO_EXCHANGE_BASE(); ~IIS_CRYPTO_EXCHANGE_BASE();
//
// Accessors for the keys we create. Note that once the calling
// application assumes ownership for one of these keys, it is the
// application's responsibility to close it.
//
HCRYPTKEY AssumeClientSessionKey() { HCRYPTKEY hTmp;
hTmp = m_hClientSessionKey; m_hClientSessionKey = CRYPT_NULL; return hTmp; }
HCRYPTKEY AssumeServerSessionKey() { HCRYPTKEY hTmp;
hTmp = m_hServerSessionKey; m_hServerSessionKey = CRYPT_NULL; return hTmp; }
protected:
//
// Create the phase 3 and 4 hash values.
//
HRESULT CreatePhase3Hash( OUT PIIS_CRYPTO_BLOB * ppHashBlob );
HRESULT CreatePhase4Hash( OUT PIIS_CRYPTO_BLOB * ppHashBlob );
//
// Various keys we create/import.
//
HCRYPTKEY m_hServerSessionKey; HCRYPTKEY m_hClientSessionKey;
private:
//
// Helper function for creating hash values.
//
HRESULT CreateHashWorker( OUT PIIS_CRYPTO_BLOB * ppHashBlob, IN BOOL fPhase3 );
}; // IIS_CRYPTO_EXCHANGE_BASE
class IIS_CRYPTO_EXCHANGE_CLIENT : public IIS_CRYPTO_EXCHANGE_BASE {
public:
//
// Constructor/destructor.
//
IIS_CRYPTO_EXCHANGE_CLIENT(); ~IIS_CRYPTO_EXCHANGE_CLIENT();
//
// The guts of the client-side multi-phase key exchange protocol.
//
HRESULT ClientPhase1( OUT PIIS_CRYPTO_BLOB * ppClientKeyExhangeKeyBlob, OUT PIIS_CRYPTO_BLOB * ppClientSignatureKeyBlob );
HRESULT ClientPhase2( IN PIIS_CRYPTO_BLOB pServerKeyExchangeKeyBlob, IN PIIS_CRYPTO_BLOB pServerSignatureKeyBlob, IN PIIS_CRYPTO_BLOB pServerSessionKeyBlob, OUT PIIS_CRYPTO_BLOB * ppClientSessionKeyBlob, OUT PIIS_CRYPTO_BLOB * ppClientHashBlob );
HRESULT ClientPhase3( IN PIIS_CRYPTO_BLOB pServerHashBlob );
//
// Accessors for the server keys we import. Note that once the calling
// application assumes ownership for one of these keys, it is the
// application's responsibility to close it.
//
HCRYPTKEY AssumeServerKeyExchangeKey() { HCRYPTKEY hTmp;
hTmp = m_hServerKeyExchangeKey; m_hServerKeyExchangeKey = CRYPT_NULL; return hTmp; }
HCRYPTKEY AssumeServerSignatureKey() { HCRYPTKEY hTmp;
hTmp = m_hServerSignatureKey; m_hServerSignatureKey = CRYPT_NULL; return hTmp; }
protected:
//
// Server-side keys we'll import.
//
HCRYPTKEY m_hServerKeyExchangeKey; HCRYPTKEY m_hServerSignatureKey;
}; // IIS_CRYPTO_EXCHANGE_CLIENT
class IIS_CRYPTO_EXCHANGE_SERVER : public IIS_CRYPTO_EXCHANGE_BASE {
public:
//
// Constructor/destructor.
//
IIS_CRYPTO_EXCHANGE_SERVER(); ~IIS_CRYPTO_EXCHANGE_SERVER();
//
// The guts of the server-side multi-phase key exchange protocol.
//
HRESULT ServerPhase1( IN PIIS_CRYPTO_BLOB pClientKeyExchangeKeyBlob, IN PIIS_CRYPTO_BLOB pClientSignatureKeyBlob, OUT PIIS_CRYPTO_BLOB * ppServerKeyExchangeKeyBlob, OUT PIIS_CRYPTO_BLOB * ppServerSignatureKeyBlob, OUT PIIS_CRYPTO_BLOB * ppServerSessionKeyBlob );
HRESULT ServerPhase2( IN PIIS_CRYPTO_BLOB pClientSessionKeyBlob, IN PIIS_CRYPTO_BLOB pClientHashBlob, OUT PIIS_CRYPTO_BLOB * ppServerHashBlob );
//
// Accessors for the client keys we import. Note that once the calling
// application assumes ownership for one of these keys, it is the
// application's responsibility to close it.
//
HCRYPTKEY AssumeClientKeyExchangeKey() { HCRYPTKEY hTmp;
hTmp = m_hClientKeyExchangeKey; m_hClientKeyExchangeKey = CRYPT_NULL; return hTmp; }
HCRYPTKEY AssumeClientSignatureKey() { HCRYPTKEY hTmp;
hTmp = m_hClientSignatureKey; m_hClientSignatureKey = CRYPT_NULL; return hTmp; }
protected:
//
// Client-side keys we'll import.
//
HCRYPTKEY m_hClientKeyExchangeKey; HCRYPTKEY m_hClientSignatureKey;
}; // IIS_CRYPTO_EXCHANGE_SERVER
#endif // _ICRYPT_HXX_
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