CryptnoxWallet.h

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/*
 * SPDX-License-Identifier: LGPL-3.0-or-later
 * Copyright (c) 2026 Cryptnox SA
 */

 
#ifndef CRYPTNOXWALLET_H
#define CRYPTNOXWALLET_H
 
/******************************************************************
 * 1. Included files
 ******************************************************************/
 
#include "platform_compat.h"
#include "CW_Defs.h"
#include "CW_Logger.h"
#include "CW_Platform.h"
#include "CW_SecureChannel.h"
#include "CW_Utils.h"
 
/******************************************************************
 * 2. Typedefs / structs (sign API)
 ******************************************************************/

#define CW_CARD_NAME_MAX_LEN  (20U)

#define CW_CARD_EMAIL_MAX_LEN (60U)

struct CW_CardInfo {
    char name[CW_CARD_NAME_MAX_LEN + 1U];    
    char email[CW_CARD_EMAIL_MAX_LEN + 1U];  
 
    CW_CardInfo() {
        name[0]  = '\0';
        email[0] = '\0';
    }
};

struct CW_SignRequest {
    CW_SecureSession& session;       
    uint8_t keyType;                 
    uint8_t signatureType;           
    uint8_t pin[CW_MAX_PIN_LENGTH];  
    bool pinLessMode;                
    const uint8_t* hash;             
    uint8_t hashLength;              
    const uint8_t* derivePath;       
    uint8_t derivePathLength;        

    explicit CW_SignRequest(CW_SecureSession& sess,
                            uint8_t kType   = CW_SIGN_CURR_K1,
                            uint8_t sigType = CW_SIGN_SIG_ECDSA_LOW_S,
                            bool pinless    = CW_SIGN_WITH_PIN)
        : session(sess), keyType(kType), signatureType(sigType),
          pinLessMode(pinless), hash(NULL), hashLength(0U),
          derivePath(NULL), derivePathLength(0U) {
        memset(pin, 0U, sizeof(pin));
    }

    ~CW_SignRequest() {
        CW_Utils::secure_wipe(pin, sizeof(pin));
    }
};

struct CW_SignResult {
    uint8_t signature[CW_RAW_SIGNATURE_SIZE]; 
    uint8_t errorCode;                        

    CW_SignResult() : errorCode(CW_NOK) {
        memset(signature, 0U, sizeof(signature));
    }
};
 
/******************************************************************
 * 3. CryptnoxWallet class
 ******************************************************************/

class CryptnoxWallet {
public:
    CryptnoxWallet(CW_NfcTransport& driver, CW_Logger& logger,
                   CW_CryptoProvider& crypto, CW_Platform& platform);
 
    CryptnoxWallet(const CryptnoxWallet&) = delete;
    CryptnoxWallet& operator=(const CryptnoxWallet&) = delete;

    bool begin();

    bool connect(CW_SecureSession& session);

    bool establishSecureChannel(CW_SecureSession& session);

    void disconnect(CW_SecureSession& session);

    bool getCardInfo(CW_SecureSession& session, CW_CardInfo* info = NULL);

    bool verifyPin(CW_SecureSession& session, const uint8_t* pin, uint8_t pinLength);

    CW_SignResult sign(CW_SignRequest& request);

    bool writeUserData(CW_SecureSession& session, uint8_t slot,
                       const uint8_t* data, uint16_t dataLength);

    static bool parseDerSignature(const uint8_t* der, uint8_t derLength,
                                  uint8_t* r, uint8_t& rLength,
                                  uint8_t* s, uint8_t& sLength);
 
private:
    CW_Logger&       _logger;   
    CW_Platform&     _platform; 
    CW_SecureChannel _secure;   
 
    bool isSecureChannelOpen(const CW_SecureSession& session) const;
    bool printPN532FirmwareVersion();
 
    /* Sign helper methods */
    bool validateSignRequest(const CW_SignRequest& request, CW_SignResult& result);
    void buildSignPayload(const CW_SignRequest& request, uint8_t* data, uint16_t& dataLength);
    bool sendSignApdu(CW_SignRequest& request, const uint8_t* data, uint16_t dataLength,
                      uint8_t* derResponse, uint16_t& derLength, CW_SignResult& result);
    bool extractRawSignature(const uint8_t* derResponse, uint16_t derLength, CW_SignResult& result);
    void debugPrintSignature(const uint8_t* signature);
};
 
#endif // CRYPTNOXWALLET_H