50 lines
1,000 B
C
50 lines
1,000 B
C
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/* CheckPtr.c
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Pointer validation routine
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Written by t-jasonf.
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*/
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#include "windows.h"
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#include "dll.h"
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/* CheckPointer()
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Parameters :
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LPVOID lp - pointer to check
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int nREADWRITE - READ_ACCESS or WRITE_ACCESS
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Returns:
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0 if process does not have that kind of access to memory at lp.
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1 if process does have access.
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*/
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int CheckPointer (void *lp, int nReadWrite)
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{
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char ch;
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int iRet;
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try
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{
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switch (nReadWrite)
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{
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case READ_ACCESS:
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ch = *((volatile char *)lp);
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break;
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case WRITE_ACCESS:
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ch = *((volatile char *)lp);
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*((volatile char *)lp) = ch;
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break;
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}
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iRet = 1;
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}
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except ( /*
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GetExceptionCode == STATUS_ACCESS_VIOLATION
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? EXCEPTION_EXECUTE_HANDLER
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: EXCEPTION_CONTINUE_SEARCH
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*/
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EXCEPTION_EXECUTE_HANDLER
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)
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{
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iRet = 0;
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}
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return iRet;
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}
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