text: /*!
   * @file common.c
   * @brief Definitions for various common components used across the Meterpreter suite.
   */
  #include "common.h"
  
  #ifdef _WIN32
  
  #define SLEEP_MAX_SEC (MAXDWORD / 1000)
  
  /*!
   * @brief Returns a unix timestamp in UTC.
   * @return Integer value representing the UTC Unix timestamp of the current time.
   */
  int current_unix_timestamp(void) {
  	SYSTEMTIME system_time;
  	FILETIME file_time;
  	ULARGE_INTEGER ularge;
  
  	GetSystemTime(&system_time);
  	SystemTimeToFileTime(&system_time, &file_time);
  
  	ularge.LowPart = file_time.dwLowDateTime;
  	ularge.HighPart = file_time.dwHighDateTime;
  	return (long)((ularge.QuadPart - 116444736000000000) / 10000000L);
  }
  
  /*!
   * @brief Sleep for the given number of seconds.
   * @param seconds DWORD value representing the number of seconds to sleep.
   * @remark This was implemented so that extended sleep times can be used (beyond the
   *         49 day limit imposed by Sleep()).
   */
  VOID sleep(DWORD seconds)
  {
  	while (seconds > SLEEP_MAX_SEC)
  	{
  		Sleep(SLEEP_MAX_SEC * 1000);
  		seconds -= SLEEP_MAX_SEC;
  	}
  	Sleep(seconds * 1000);
  }
  
  #else
  
  #include <sys/time.h>
  
  /*!
   * @brief Returns a unix timestamp in UTC.
   * @return Integer value representing the UTC Unix timestamp of the current time.
   */
  int current_unix_timestamp(void) {
  	struct timeval tv;
  	struct timezone tz;
  
  	memset(&tv, 0, sizeof(tv));
  	memset(&tz, 0, sizeof(tz));
  
  	gettimeofday(&tv, &tz);
  	return (long) tv.tv_usec;
  }
  #endif
  
  #ifndef _WIN32
  
  int debugging_enabled;
  
  /*!
   * @brief Writes debug to a temporary file based on the current PID.
   */
  void real_dprintf(char *filename, int line, const char *function, char *format, ...)
  {
  	va_list args;
  	char buffer[2048];
  	int size;
  	static int fd;
  	int retried = 0;
  
  	filename = basename(filename);
  	size = snprintf(buffer, sizeof(buffer), "[%s:%d (%s)] ", filename, line, function);
  
  	va_start(args, format);
  	vsnprintf(buffer + size, sizeof(buffer) - size, format, args);
  	strcat(buffer, "\n");
  	va_end(args);
  
  retry_log:
  	if(fd <= 0) {
  		char filename[128];
  		sprintf(filename, "/tmp/meterpreter.log.%d%s", getpid(), retried ? ".retry" : "" );
  
  		fd = open(filename, O_RDWR|O_TRUNC|O_CREAT|O_SYNC, 0644);
  
  		if(fd <= 0) return;
  	}
  
  	if(write(fd, buffer, strlen(buffer)) == -1 && (errno == EBADF)) {
  		fd = -1;
  		retried++;
  		goto retry_log;
  	}
  }
  
  void enable_debugging()
  {
  	debugging_enabled = 1;
  }
  
  #endif
  
  VOID xor_bytes(DWORD xorKey, LPBYTE buffer, DWORD bufferSize)
  {
  	static BOOL initialised = FALSE;
  	if (!initialised)
  	{
  		srand((unsigned int)time(NULL));
  		initialised = TRUE;
  	}
  
  	LPBYTE xor = (LPBYTE)&xorKey;
  
  	for (DWORD i = 0; i < bufferSize; ++i)
  	{
  		buffer[i] ^= xor[i % sizeof(DWORD)];
  	}
  }
  