/*
 * Copyright (C) 1996-2023 The Squid Software Foundation and contributors
 *
 * Squid software is distributed under GPLv2+ license and includes
 * contributions from numerous individuals and organizations.
 * Please see the COPYING and CONTRIBUTORS files for details.
 */

#ifndef SQUID_SRC_SSL_CERT_VALIDATE_MESSAGE_H
#define SQUID_SRC_SSL_CERT_VALIDATE_MESSAGE_H

#include "base/RefCount.h"
#include "helper/ResultCode.h"
#include "ssl/crtd_message.h"
#include "ssl/support.h"

#include <vector>

namespace Ssl
{

/**
 * This class is used to hold the required information to build
 * a request message for the certificate validator helper
 */
class CertValidationRequest
{
public:
    Security::SessionPointer ssl;
    Security::CertErrors *errors = nullptr; ///< The list of errors detected
    std::string domainName; ///< The server name
};

/**
 * This class is used to store information found in certificate validation
 * response messages read from certificate validator helper
 */
class CertValidationResponse: public RefCountable
{
public:
    typedef RefCount<CertValidationResponse> Pointer;

    /**
     * This class used to hold error information returned from
     * cert validator helper.
     */
    class  RecvdError
    {
    public:
        void setCert(X509 *);  ///< Sets cert to the given certificate
        int id = 0; ///<  The id of the error
        Security::ErrorCode error_no = 0; ///< The OpenSSL error code
        std::string error_reason; ///< A string describing the error
        Security::CertPointer cert; ///< The broken certificate
        int error_depth = -1; ///< The error depth
    };

    typedef std::vector<RecvdError> RecvdErrors;
    explicit CertValidationResponse(const Security::SessionPointer &aSession) : ssl(aSession) {}

    static uint64_t MemoryUsedByResponse(const CertValidationResponse::Pointer &);

    /// Search in errors list for the error item with id=errorId.
    /// If none found a new RecvdError item added with the given id;
    RecvdError &getError(int errorId);
    RecvdErrors errors; ///< The list of parsed errors
    Helper::ResultCode resultCode = Helper::Unknown; ///< The helper result code
    Security::SessionPointer ssl;
};

/**
 * This class is responsible for composing or parsing messages destined to
 * or coming from a certificate validation helper.
 * The messages format is:
\verbatim
   response/request-code SP body-length SP [key=value ...] EOL
\endverbatim
 * \note EOL for this interface is character 0x01
 */
class CertValidationMsg : public CrtdMessage
{
private:
    /**
     * This class used to hold the certId/cert pairs found
     * in cert validation messages.
     */
    class CertItem
    {
    public:
        std::string name; ///< The certificate Id to use
        Security::CertPointer cert;       ///< A pointer to certificate
        void setCert(X509 *); ///< Sets cert to the given certificate
    };

public:
    CertValidationMsg(MessageKind kind): CrtdMessage(kind) {}

    /// Build a request message for the cert validation helper
    /// using information provided by vcert object
    void composeRequest(CertValidationRequest const &vcert);

    /// Parse a response message and fill the resp object with parsed information
    bool parseResponse(CertValidationResponse &resp);

    /// Search a CertItems list for the certificate with ID "name"
    X509 *getCertByName(std::vector<CertItem> const &, std::string const & name);

    /// String code for "cert_validate" messages
    static const std::string code_cert_validate;
    /// Parameter name for passing intended domain name
    static const std::string param_domain;
    /// Parameter name for passing SSL certificates
    static const std::string param_cert;
    /// Parameter name for passing the major SSL error
    static const std::string param_error_name;
    /// Parameter name for passing the error reason
    static const std::string param_error_reason;
    /// Parameter name for passing the error cert ID
    static const std::string param_error_cert;
    /// Parameter name for passing the error depth
    static const std::string param_error_depth;
    /// Parameter name for SSL version
    static const std::string param_proto_version;
    /// Parameter name for SSL cipher
    static const std::string param_cipher;

private:
    void tryParsingResponse(CertValidationResponse &);
};

}//namespace Ssl

#endif /* SQUID_SRC_SSL_CERT_VALIDATE_MESSAGE_H */