/********************************************************
 * ADO.NET 2.0 Data Provider for SQLite Version 3.X
 * Written by Robert Simpson (robert@blackcastlesoft.com)
 * 
 * Released to the public domain, use at your own risk!
 ********************************************************/

#ifndef SQLITE_OMIT_DISKIO
#ifdef SQLITE_HAS_CODEC

#include <windows.h>
................................................................................
    break;
  }

  return data;
}

/* Derive an encryption key from a user-supplied buffer */
static HCRYPTKEY DeriveKey(const void *pKey, int nKeyLen)
{
  HCRYPTHASH hHash = 0;
  HCRYPTKEY  hKey;

  if (!pKey || !nKeyLen) return 0;

  if (!InitializeProvider())
  {
    return MAXDWORD;
  }

  {
    MUTEX_LOGIC( sqlite3_mutex *pMaster = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER); )
    sqlite3_mutex_enter(pMaster);

    if (CryptCreateHash(g_hProvider, CALG_SHA1, 0, 0, &hHash))
    {
      if (CryptHashData(hHash, (LPBYTE)pKey, nKeyLen, 0))
      {
        CryptDeriveKey(g_hProvider, CALG_RC4, hHash, 0, &hKey);
      }
      CryptDestroyHash(hHash);
    }

    sqlite3_mutex_leave(pMaster);
................................................................................
  LPCRYPTBLOCK pBlock = (LPCRYPTBLOCK)sqlite3pager_get_codecarg(p);

  if (ppKey) *ppKey = 0;
  if (pnKeyLen && pBlock) *pnKeyLen = 1;
}

/* We do not attach this key to the temp store, only the main database. */
SQLITE_API int sqlite3_key(sqlite3 *db, const unsigned char *pKey, int nKeySize)
{
  return sqlite3CodecAttach(db, 0, pKey, nKeySize);





}

/* Changes the encryption key for an existing database. */
SQLITE_API int sqlite3_rekey(sqlite3 *db, const unsigned char *pKey, int nKeySize)
{
  Btree *pbt = db->aDb[0].pBt;
  Pager *p = sqlite3BtreePager(pbt);
  LPCRYPTBLOCK pBlock = (LPCRYPTBLOCK)sqlite3pager_get_codecarg(p);
  HCRYPTKEY hKey = DeriveKey(pKey, nKeySize);
  int rc = SQLITE_ERROR;

  if (hKey == MAXDWORD)
  {
    sqlite3Error(db, rc, SQLITECRYPTERROR_PROVIDER);
    return rc;
  }
................................................................................
    sqlite3PagerSetCodec(p, NULL, NULL, NULL, NULL);
  }

  sqlite3_mutex_leave(db->mutex);

  return rc;
}






#endif /* SQLITE_HAS_CODEC */
#endif /* SQLITE_OMIT_DISKIO */

/********************************************************
 * ADO.NET 2.0 Data Provider for SQLite Version 3.X
 * Written by Robert Simpson (robert@blackcastlesoft.com)
 *
 * Released to the public domain, use at your own risk!
 ********************************************************/

#ifndef SQLITE_OMIT_DISKIO
#ifdef SQLITE_HAS_CODEC

#include <windows.h>
................................................................................
    break;
  }

  return data;
}

/* Derive an encryption key from a user-supplied buffer */
static HCRYPTKEY DeriveKey(const void *pKey, int nKey)
{
  HCRYPTHASH hHash = 0;
  HCRYPTKEY  hKey;

  if (!pKey || !nKey) return 0;

  if (!InitializeProvider())
  {
    return MAXDWORD;
  }

  {
    MUTEX_LOGIC( sqlite3_mutex *pMaster = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER); )
    sqlite3_mutex_enter(pMaster);

    if (CryptCreateHash(g_hProvider, CALG_SHA1, 0, 0, &hHash))
    {
      if (CryptHashData(hHash, (LPBYTE)pKey, nKey, 0))
      {
        CryptDeriveKey(g_hProvider, CALG_RC4, hHash, 0, &hKey);
      }
      CryptDestroyHash(hHash);
    }

    sqlite3_mutex_leave(pMaster);
................................................................................
  LPCRYPTBLOCK pBlock = (LPCRYPTBLOCK)sqlite3pager_get_codecarg(p);

  if (ppKey) *ppKey = 0;
  if (pnKeyLen && pBlock) *pnKeyLen = 1;
}

/* We do not attach this key to the temp store, only the main database. */
SQLITE_API int sqlite3_key_v2(sqlite3 *db, const char *zDbName, const void *pKey, int nKey)
{
  return sqlite3CodecAttach(db, 0, pKey, nKey);
}

SQLITE_API int sqlite3_key(sqlite3 *db, const void *pKey, int nKey)
{
  return sqlite3_key_v2(db, 0, pKey, nKey);
}

/* Changes the encryption key for an existing database. */
SQLITE_API int sqlite3_rekey_v2(sqlite3 *db, const char *zDbName, const void *pKey, int nKey)
{
  Btree *pbt = db->aDb[0].pBt;
  Pager *p = sqlite3BtreePager(pbt);
  LPCRYPTBLOCK pBlock = (LPCRYPTBLOCK)sqlite3pager_get_codecarg(p);
  HCRYPTKEY hKey = DeriveKey(pKey, nKey);
  int rc = SQLITE_ERROR;

  if (hKey == MAXDWORD)
  {
    sqlite3Error(db, rc, SQLITECRYPTERROR_PROVIDER);
    return rc;
  }
................................................................................
    sqlite3PagerSetCodec(p, NULL, NULL, NULL, NULL);
  }

  sqlite3_mutex_leave(db->mutex);

  return rc;
}

SQLITE_API int sqlite3_rekey(sqlite3 *db, const void *pKey, int nKey)
{
  return sqlite3_rekey_v2(db, 0, pKey, nKey);
}

#endif /* SQLITE_HAS_CODEC */
#endif /* SQLITE_OMIT_DISKIO */