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zpostfactozpostfacto
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Move 25519 crypto to a separate header.
Getting things closer to how they are organized in the Steam main branch so I can stop having these files diverge so much. Also tweaked defines.
1 parent 66e2a65 commit 0307add

15 files changed

+201
-151
lines changed

‎CMakeLists.txt‎

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@@ -20,6 +20,7 @@ set(MSVC_RUNTIME "dynamic")
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configure_msvc_runtime()
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print_default_msvc_flags()
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add_definitions( -DVALVE_CRYPTO_ENABLE_25519 )
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if(CMAKE_CXX_COMPILER_ID MATCHES "MSVC")
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add_definitions(
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-D_CRT_SECURE_NO_WARNINGS

‎src/common/crypto.h‎

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@@ -100,25 +100,6 @@ namespace CCrypto
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const void *pAdditionalAuthenticationData, size_t cbAuthenticationData, // Optional additional authentication data. Not encrypted, but will be included in the tag, so it can be authenticated.
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size_t cbTag // Last N bytes in your buffer are assumed to be a tag, and will be checked
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);
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//
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// Secure key exchange (curve25519 elliptic-curve Diffie-Hellman key exchange)
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//
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// Generate a curve25519 key pair for Diffie-Hellman secure key exchange
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void GenerateKeyExchangeKeyPair( CECKeyExchangePublicKey *pPublicKey, CECKeyExchangePrivateKey *pPrivateKey );
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bool PerformKeyExchange( const CECKeyExchangePrivateKey &localPrivateKey, const CECKeyExchangePublicKey &remotePublicKey, SHA256Digest_t *pSharedSecretOut );
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//
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// Signing and verification (ed25519 elliptic-curve signature scheme)
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//
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// Generate an ed25519 key pair for public-key signature generation
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void GenerateSigningKeyPair( CECSigningPublicKey *pPublicKey, CECSigningPrivateKey *pPrivateKey );
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// Legacy compatibility - use the key methods
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inline void GenerateSignature( const void *pData, size_t cbData, const CECSigningPrivateKey &privateKey, CryptoSignature_t *pSignatureOut ) { privateKey.GenerateSignature( pData, cbData, pSignatureOut ); }
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inline bool VerifySignature( const void *pData, size_t cbData, const CECSigningPublicKey &publicKey, const CryptoSignature_t &signature ) { return publicKey.VerifySignature( pData, cbData, signature ); }
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bool HexEncode( const void *pubData, const uint32 cubData, char *pchEncodedData, uint32 cchEncodedData );
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bool HexDecode( const char *pchData, void *pubDecodedData, uint32 *pcubDecodedData );

‎src/common/crypto_25519.h‎

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//========= Copyright Valve LLC, All rights reserved. =========================
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#ifndef CRYPTO_25519_H
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#define CRYPTO_25519_H
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#include "crypto_constants.h"
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#include "keypair.h"
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class CEC25519KeyBase : public CCryptoKeyBase_RawBuffer
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{
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public:
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virtual ~CEC25519KeyBase();
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virtual bool IsValid() const override;
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virtual uint32 GetRawData( void *pData ) const override;
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virtual void Wipe() override;
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void *evp_pkey() const { return m_evp_pkey; }
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protected:
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virtual bool SetRawData( const void *pData, size_t cbData ) override;
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inline CEC25519KeyBase( ECryptoKeyType keyType ) : CCryptoKeyBase_RawBuffer( keyType ), m_evp_pkey(nullptr) {}
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// Actually EVP_PKEY*, but we don't want to include OpenSSL headers here,
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// especially since we might not actually be using OpenSSL for this at all!
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void *m_evp_pkey;
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};
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//-----------------------------------------------------------------------------
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// Purpose: Common base for x25519 and ed25519 public keys on the 25519 curve
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// The raw data is 32 bytes
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//-----------------------------------------------------------------------------
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class CEC25519PublicKeyBase : public CEC25519KeyBase
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{
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public:
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virtual ~CEC25519PublicKeyBase();
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protected:
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CEC25519PublicKeyBase( ECryptoKeyType eType ) : CEC25519KeyBase( eType ) { }
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};
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//-----------------------------------------------------------------------------
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// Purpose: Common base for x25519 and ed25519 private keys on the 25519 curve
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// The raw data is 32 bytes.
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// NOTE: An old version also stored the public key in the raw data.
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// We don't do that anymore.) If you want that, get the public
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// key data specifically
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//-----------------------------------------------------------------------------
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class CEC25519PrivateKeyBase : public CEC25519KeyBase
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{
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public:
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virtual ~CEC25519PrivateKeyBase();
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virtual void Wipe() override;
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bool GetPublicKey( CEC25519PublicKeyBase *pPublicKey ) const;
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bool MatchesPublicKey( const CEC25519PublicKeyBase &pPublicKey ) const;
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const uint8 *GetPublicKeyRawData() const { return m_publicKey; }
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protected:
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CEC25519PrivateKeyBase( ECryptoKeyType eType ) : CEC25519KeyBase( eType ) { }
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// We keep a copy of the public key cached.
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// It is not considered part of the raw key data,
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// as was previously the case.)
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uint8 m_publicKey[32];
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bool CachePublicKey();
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virtual bool SetRawData( const void *pData, size_t cbData ) override;
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};
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//-----------------------------------------------------------------------------
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// Purpose: Encapsulates an elliptic-curve signature private key (x25519)
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//-----------------------------------------------------------------------------
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class CECKeyExchangePrivateKey : public CEC25519PrivateKeyBase
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{
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public:
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CECKeyExchangePrivateKey() : CEC25519PrivateKeyBase( k_ECryptoKeyTypeKeyExchangePrivate ) { }
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virtual ~CECKeyExchangePrivateKey();
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};
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//-----------------------------------------------------------------------------
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// Purpose: Encapsulates an elliptic-curve key-exchange public key (curve25519)
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// Internally, this is stored as a 32-byte binary data blob
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//-----------------------------------------------------------------------------
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class CECKeyExchangePublicKey : public CEC25519PublicKeyBase
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{
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public:
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CECKeyExchangePublicKey() : CEC25519PublicKeyBase( k_ECryptoKeyTypeKeyExchangePublic ) { }
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virtual ~CECKeyExchangePublicKey();
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};
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//-----------------------------------------------------------------------------
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// Purpose: Encapsulates an elliptic-curve signature private key (ed25519)
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// Internally, this is stored as a 64-byte (public, private) pair
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//-----------------------------------------------------------------------------
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class CECSigningPrivateKey : public CEC25519PrivateKeyBase
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{
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public:
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CECSigningPrivateKey() : CEC25519PrivateKeyBase( k_ECryptoKeyTypeSigningPrivate ) { }
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// Load from PEM
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virtual bool LoadFromAndWipeBuffer( void *pBuffer, size_t cBytes ) override;
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// Purpose: Get key in PEM text format
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// Input: pchPEMData - Pointer to string buffer to store output in (or NULL to just calculate required size)
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// cubPEMData - Size of pchPEMData buffer
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// pcubPEMData - Pointer to number of bytes written to pchPEMData (including terminating nul), or
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// required size of pchPEMData if it is NULL or not big enough.
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bool GetAsPEM( char *pchPEMData, uint32 cubPEMData, uint32 *pcubPEMData ) const;
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// Parses OpenSSH PEM block.
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// WARNING: DOES NOT WIPE INPUT.
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bool ParsePEM( const char *pBuffer, size_t cBytes );
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// Generate an ed25519 public-key signature
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void GenerateSignature( const void *pData, size_t cbData, CryptoSignature_t *pSignatureOut ) const;
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};
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//-----------------------------------------------------------------------------
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// Purpose: Encapsulates an elliptic-curve signature public key (x25519)
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// Internally, this is stored as a 32-byte binary data blob
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//-----------------------------------------------------------------------------
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class CECSigningPublicKey : public CEC25519PublicKeyBase
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{
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public:
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CECSigningPublicKey() : CEC25519PublicKeyBase( k_ECryptoKeyTypeSigningPublic ) { }
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virtual bool LoadFromAndWipeBuffer( void *pBuffer, size_t cBytes ) override;
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bool GetAsOpenSSHAuthorizedKeys( char *pchData, uint32 cubData, uint32 *pcubData, const char *pszComment = "" ) const;
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bool SetFromOpenSSHAuthorizedKeys( const char *pchData, size_t cbData );
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bool VerifySignature( const void *pData, size_t cbData, const CryptoSignature_t &signature ) const;
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};
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#ifdef VALVE_CRYPTO_ENABLE_25519
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namespace CCrypto
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{
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//
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// Secure key exchange (curve25519 elliptic-curve Diffie-Hellman key exchange)
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//
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// Generate a X25519 key pair for Diffie-Hellman secure key exchange.
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// pPublicKey can be null. (Since the private key also has a copy of the public key.)
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void GenerateKeyExchangeKeyPair( CECKeyExchangePublicKey *pPublicKey, CECKeyExchangePrivateKey *pPrivateKey );
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// Do Diffie-Hellman secure key exchange.
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// NOTE: this actually returns the SHA256 of the raw DH result. I don't know why.
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bool PerformKeyExchange( const CECKeyExchangePrivateKey &localPrivateKey, const CECKeyExchangePublicKey &remotePublicKey, SHA256Digest_t *pSharedSecretOut );
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//
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// Signing and verification (ed25519 elliptic-curve signature scheme)
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//
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// Generate an ed25519 key pair for public-key signature generation
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void GenerateSigningKeyPair( CECSigningPublicKey *pPublicKey, CECSigningPrivateKey *pPrivateKey );
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// Legacy compatibility - use the key methods
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inline void GenerateSignature( const void *pData, size_t cbData, const CECSigningPrivateKey &privateKey, CryptoSignature_t *pSignatureOut ) { privateKey.GenerateSignature( pData, cbData, pSignatureOut ); }
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inline bool VerifySignature( const void *pData, size_t cbData, const CECSigningPublicKey &publicKey, const CryptoSignature_t &signature ) { return publicKey.VerifySignature( pData, cbData, signature ); }
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};
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#endif // #ifdef VALVE_CRYPTO_ENABLE_25519
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#endif // CRYPTO_H

‎src/common/crypto_25519_donna.cpp‎

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//========= Copyright Valve LLC, All rights reserved. ========================
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#include "crypto.h"
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#include "crypto_25519.h"
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#include <tier0/dbg.h>
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#ifdef VALVE_CRYPTO_25519_DONNA
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return true;
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}
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#endif // #ifdef GNS_CRYPTO_25519_REF
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#endif // #ifdef VALVE_CRYPTO_25519_DONNA
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‎src/common/crypto_25519_openssl.cpp‎

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//========= Copyright Valve LLC, All rights reserved. ========================
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#include "crypto.h"
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#include "crypto_25519.h"
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#include <tier0/dbg.h>
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#ifdef STEAMNETWORKINGSOCKETS_CRYPTO_25519_OPENSSL

‎src/common/keypair.cpp‎

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#include "keypair.h"
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#include "crypto.h"
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#include "crypto_25519.h"
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#include <tier1/utlbuffer.h>
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static const char k_szOpenSSHPrivatKeyPEMHeader[] = "-----BEGIN OPENSSH PRIVATE KEY-----";

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