cpl_http.h

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/******************************************************************************
 * $Id: cpl_http.h 0aaf941e652f4950616aff612169985b6fd66cdd 2021-10-24 14:24:39 +0200 Even Rouault $
 *
 * Project:  Common Portability Library
 * Purpose:  Function wrapper for libcurl HTTP access.
 * Author:   Frank Warmerdam, warmerdam@pobox.com
 *
 ******************************************************************************
 * Copyright (c) 2006, Frank Warmerdam
 * Copyright (c) 2009, Even Rouault <even dot rouault at spatialys.com>
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included
 * in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 * DEALINGS IN THE SOFTWARE.
 ****************************************************************************/
 
#ifndef CPL_HTTP_H_INCLUDED
#define CPL_HTTP_H_INCLUDED
 
#include "cpl_conv.h"
#include "cpl_string.h"
#include "cpl_progress.h"
#include "cpl_vsi.h"


#ifndef CPL_HTTP_MAX_RETRY
#define CPL_HTTP_MAX_RETRY      0
#endif
 
#ifndef CPL_HTTP_RETRY_DELAY
#define CPL_HTTP_RETRY_DELAY    30.0
#endif
 
CPL_C_START

typedef struct { char **papszHeaders;
 GByte *pabyData; int    nDataLen;
} CPLMimePart;

typedef struct {
    int     nStatus;

    char    *pszContentType;

    char    *pszErrBuf;

    int     nDataLen;
    int     nDataAlloc;

    GByte   *pabyData;

    char    **papszHeaders;

    int     nMimePartCount;

    CPLMimePart *pasMimePart;
 
} CPLHTTPResult;

typedef size_t (*CPLHTTPFetchWriteFunc)(void *pBuffer, size_t nSize, size_t nMemb, void *pWriteArg);
 
int CPL_DLL   CPLHTTPEnabled( void );
CPLHTTPResult CPL_DLL *CPLHTTPFetch( const char *pszURL, CSLConstList papszOptions);
CPLHTTPResult CPL_DLL *CPLHTTPFetchEx( const char *pszURL,CSLConstList papszOptions,
                                       GDALProgressFunc pfnProgress,
                                       void *pProgressArg,
                                       CPLHTTPFetchWriteFunc pfnWrite,
                                       void *pWriteArg);
CPLHTTPResult CPL_DLL **CPLHTTPMultiFetch( const char * const * papszURL,
                                           int nURLCount,
                                           int nMaxSimultaneous,
                                           CSLConstList papszOptions);
 
void CPL_DLL  CPLHTTPCleanup( void );
void CPL_DLL  CPLHTTPDestroyResult( CPLHTTPResult *psResult );
void CPL_DLL  CPLHTTPDestroyMultiResult( CPLHTTPResult **papsResults, int nCount );
int  CPL_DLL  CPLHTTPParseMultipartMime( CPLHTTPResult *psResult );
 
/* -------------------------------------------------------------------- */
/* To install an alternate network layer to the default Curl one        */
/* -------------------------------------------------------------------- */
typedef CPLHTTPResult* (*CPLHTTPFetchCallbackFunc)( const char *pszURL,
                                                    CSLConstList papszOptions,
                                                    GDALProgressFunc pfnProgress,
                                                    void *pProgressArg,
                                                    CPLHTTPFetchWriteFunc pfnWrite,
                                                    void *pWriteArg,
                                                    void* pUserData );
 
void CPL_DLL CPLHTTPSetFetchCallback( CPLHTTPFetchCallbackFunc pFunc,
                                      void* pUserData );
 
int CPL_DLL  CPLHTTPPushFetchCallback( CPLHTTPFetchCallbackFunc pFunc,
                                       void* pUserData );
int CPL_DLL  CPLHTTPPopFetchCallback(void);
 
/* -------------------------------------------------------------------- */
/*      The following is related to OAuth2 authorization around         */
/*      google services like fusion tables, and potentially others      */
/*      in the future.  Code in cpl_google_oauth2.cpp.                  */
/*                                                                      */
/*      These services are built on CPL HTTP services.                  */
/* -------------------------------------------------------------------- */
 
char CPL_DLL *GOA2GetAuthorizationURL( const char *pszScope );
char CPL_DLL *GOA2GetRefreshToken( const char *pszAuthToken,
                                   const char *pszScope );
char CPL_DLL *GOA2GetAccessToken( const char *pszRefreshToken,
                                  const char *pszScope );
 
char  CPL_DLL **GOA2GetAccessTokenFromServiceAccount(
                                        const char* pszPrivateKey,
                                        const char* pszClientEmail,
                                        const char* pszScope,
                                        CSLConstList papszAdditionalClaims,
                                        CSLConstList papszOptions);
 
char CPL_DLL **GOA2GetAccessTokenFromCloudEngineVM( CSLConstList papszOptions );
 
CPL_C_END
 
#if defined(__cplusplus) && !defined(CPL_SUPRESS_CPLUSPLUS)
// Not sure if this belong here, used in cpl_http.cpp, cpl_vsil_curl.cpp and frmts/wms/gdalhttp.cpp
void CPL_DLL* CPLHTTPSetOptions(void *pcurl, const char *pszURL, const char * const* papszOptions);
char** CPLHTTPGetOptionsFromEnv();
double CPLHTTPGetNewRetryDelay(int response_code, double dfOldDelay,
                               const char* pszErrBuf, const char* pszCurlError);
void CPL_DLL* CPLHTTPIgnoreSigPipe();
void CPL_DLL CPLHTTPRestoreSigPipeHandler(void* old_handler);
bool CPLMultiPerformWait(void* hCurlMultiHandle, int& repeats);
 
bool CPL_DLL CPLIsMachinePotentiallyGCEInstance();
bool CPLIsMachineForSureGCEInstance();

class GOA2Manager
{
    public:
 
        GOA2Manager();

        typedef enum
        {
            NONE,
            GCE,
            ACCESS_TOKEN_FROM_REFRESH,
            SERVICE_ACCOUNT
        } AuthMethod;
 
        bool SetAuthFromGCE( CSLConstList papszOptions );
        bool SetAuthFromRefreshToken( const char* pszRefreshToken,
                                      const char* pszClientId,
                                      const char* pszClientSecret,
                                      CSLConstList papszOptions );
        bool SetAuthFromServiceAccount(const char* pszPrivateKey,
                                       const char* pszClientEmail,
                                       const char* pszScope,
                                       CSLConstList papszAdditionalClaims,
                                       CSLConstList papszOptions );

        AuthMethod GetAuthMethod() const { return m_eMethod; }
 
        const char* GetBearer() const;

        const CPLString& GetPrivateKey() const { return m_osPrivateKey; }

        const CPLString& GetClientEmail() const { return m_osClientEmail; }
 
    private:
 
        mutable CPLString       m_osCurrentBearer{};
        mutable time_t          m_nExpirationTime = 0;
        AuthMethod      m_eMethod = NONE;
 
        // for ACCESS_TOKEN_FROM_REFRESH
        CPLString       m_osClientId{};
        CPLString       m_osClientSecret{};
        CPLString       m_osRefreshToken{};
 
        // for SERVICE_ACCOUNT
        CPLString       m_osPrivateKey{};
        CPLString       m_osClientEmail{};
        CPLString       m_osScope{};
        CPLStringList   m_aosAdditionalClaims{};
 
        CPLStringList   m_aosOptions{};
};
 
 
#endif // __cplusplus
 
#endif /* ndef CPL_HTTP_H_INCLUDED */