#include <stdio.h>
#include "libsockets.h"
#include "libkeef.h"        // for strmatch(), etc.

#if defined (UNIX)
  #include <signal.h>       // for signal()
  #include <sys/signal.h>   // for SIGBUS, etc.
  #include <stdarg.h>
#else if defined(WIN32) // Windows
  #include <winsock.h>      // for closesocket()
  #include <direct.h>       // for _getcwd()
  #include <process.h>      // for getpid()

  #define  sleep(SECS)           Sleep(SECS*1000)
  #define  close(SOCKET)         closesocket(SOCKET)
  #define  read(SOCKET,BUF,LEN)  recv(SOCKET,BUF,LEN,/*flags=*/0)
  #define  write(SOCKET,BUF,LEN) send(SOCKET,BUF,LEN,/*flags=*/0)
#endif

#include <time.h>            // for time(), strftime(), etc.

/*global*/int g_fDebug     = 0;

#define	ErrorLog	printf
#define	DebugLog	if (g_fDebug) printf

#define MAXLEN_HOSTNAME   200

#ifndef PATH_SLASH
 #ifdef UNIX
  #define PATH_SLASH '/'
 #else
  #define PATH_SLASH '\\'
 #endif
#endif

#ifndef TXTNL
 #define TXTNL  "\r\n"
#endif

#define MAXLEN_RESPONSE     100

//typedef struct
//{
//	int   iPortNum;
//	char  szResponse[MAXLEN_RESPONSE+1];
//	int   iProtocol;
//	void* pNext;
//}
//PORT;

//-----------------------------------------------------------------------------
static char *g_Synopsis[] = {
//-----------------------------------------------------------------------------
	" ",
	"scan - scan a given range of sockets on a given machine",
	" ",
	"usage: scan [-v] <hostname> [<StartSocket> [<EndSocket>]]",
	" ",
	"where:",
	"  -v            : verbosity for sockets debugging",
	"  <hostname>    : can be a hostname or an IP address",
	"  <StartSocket> : should be >= 1",
	"  <EndSocket>   : should be >= StartSocket",
	" ",
	"History:",
	"  17 Aug 99 : keef wrote",
	" ",
	"(c) Copyright 1999 Ridgeware, Inc.",
	" ",
	NULL
};

//-----------------------------------------------------------------------------
static void Exit (int iExitCode)
//-----------------------------------------------------------------------------
{
	#ifdef WIN32
	WSACleanup();
	#endif

	exit (iExitCode);

} // Exit

//-----------------------------------------------------------------------------
static void SynopsisAndExit ()
//-----------------------------------------------------------------------------
{
	for (int ii=0; g_Synopsis[ii]; ++ii)
	{
		printf ("%s\n", g_Synopsis[ii]);
	}

	Exit(0);

} // SynopsisAndExit

//------------------------------------------------------------------------------
main (int argc, char* argv[])
//------------------------------------------------------------------------------
{
	char*  pszHostname  = NULL;
	char*  pszStartPort = NULL;
	char*  pszEndPort   = NULL;
	char** pArgArray[]  = {&pszHostname, &pszStartPort, &pszEndPort, NULL};
	int    iThisArg     = 0;
	int    iMaxArgs     = 3;
	BOOL   fHTML        = FALSE;
	int    iStartPort   = 1;
	int    iEndPort     = 10000;

	for (int ii=1; ii<argc; ++ii)
	{
		if (strmatch (argv[ii], "-v"))
			g_fDebug = 1;
		else
		{
			if (iThisArg >= iMaxArgs)
			{
				printf ("scan: argument '%s' not understood.\n", argv[ii]);
				SynopsisAndExit();
			}
			
			*(pArgArray[iThisArg]) = argv[ii];
			++iThisArg;
		}
	}

	// check required args:
	if (!pszHostname || !(*pszHostname))
		SynopsisAndExit ();

	if (pszStartPort)
		iStartPort = atoi (pszStartPort);

	if (pszEndPort)
		iEndPort = atoi (pszEndPort);

	if ((iEndPort < iStartPort) || !iEndPort || !iStartPort)
	{
		ErrorLog ("scan: illegal port number range: %d -> %d\n", iStartPort, iEndPort);
		Exit (-1);
	}

	#ifdef WIN32
	WORD wVersionRequested = MAKEWORD(1,1); 
	WSADATA wsaData; 
	if (WSAStartup (wVersionRequested, &wsaData))
	{
		ErrorLog ("scan: could not find a compatible WINSOCK DLL\n");
		Exit (-1);
 	}
	#endif

	struct sockaddr_in AddrServer;
	int    iLineNum = 0;
	int    fdSocket;

	DebugLog ("Resolving hostname '%s' into an IP address...\n", pszHostname);
	if (!ValidateHost (&AddrServer, pszHostname))
	{
		ErrorLog ("scan: could not resolve hostname '%s' into an IP address.\n", pszHostname);
		Exit (1);
	}

	char szResultsFile[200];
	sprintf (szResultsFile, "data/scan:%s", pszHostname);
	FILE* fpResults = fopen (szResultsFile, "w");
	if (fpResults)
	{
		fprintf (fpResults, "%s : looping through ports : %d -> %d\n", pszHostname, iStartPort, iEndPort);
		fclose (fpResults);
	}

	int  iNumPorts = 0;
	char szResponse[MAXLEN_RESPONSE+2];

	printf ("scan: looping through ports: %d -> %d\n", iStartPort, iEndPort);
	for (int iPortNum=iStartPort; iPortNum<=iEndPort; ++iPortNum)
	{
		DebugLog (":: attempting %d...\n", iPortNum);
		AddrServer.sin_port = htons(iPortNum);

		if ((fdSocket = socket (AF_INET, SOCK_STREAM, 0)) < 0)
		{
			ErrorLog ("scan: can't get a new stream socket descriptor.\n");
			Exit (1);
		}

		//DWORD dwNonBlocking = 1;
		//if (ioctl (fdSocket, FIONBIO, &dwNonBlocking) < 0)
		//	ErrorLog (":: warning (port %d) -- could not set socket to NON-BLOCKING mode.\n", iPortNum);

		if (connect (fdSocket,
					 (struct sockaddr *) &AddrServer,
					 sizeof(struct sockaddr_in)) >= 0)
		{
			++iNumPorts;
			DebugLog (":: --> somebody picked up the phone!\n");

			szResponse[0] = 0;
			ssize_t iLen = 0;
			char *pszBadProto = NULL;

			switch (iPortNum)
			{
//				case 79:  pszBadProto = "finger";
//				case 111: pszBadProto = "sunrpc";
//					break;

				case 80: // http
					SocketWrite (fdSocket, "GET / HTTP/1.0\n\n");
					break;

				default:
					SocketWrite (fdSocket, "FRED\n\n");
			}

			if (pszBadProto)
			{
				DebugLog (":: --> skipping read (because we know %s hangs)\n", pszBadProto);
				strcpy (szResponse, "read skipped by keef (");
				strcat (szResponse, pszBadProto);
				strcat (szResponse, " hangs on read)");
				iLen = strlen(szResponse);
			}
			else
			{
				// store the response (if any):
				iLen = read (fdSocket, szResponse, MAXLEN_RESPONSE);
				szResponse[iLen] = 0;
			}

			DebugLog (":: --> %lu bytes of 'greeting' when they answered the phone\n", iLen);

			// condense response into a one liner:
			for (int ii=0; ii<iLen; ++ii)
			{
				switch (szResponse[ii])
				{
				case 10:
				case 13:
					szResponse[ii] = ' ';
					break;
				default:
					if (szResponse[ii] < ' ')
						szResponse[ii] = '^';
				}
			}

			printf ("%s : %d : %s\n", pszHostname, iPortNum, szResponse);

			fpResults = fopen (szResultsFile, "a");
			if (fpResults)
			{
				fprintf (fpResults, "%s : %d : %s\n", pszHostname, iPortNum, szResponse);
				fclose (fpResults);
			}

		} // if port connected

		close (fdSocket);

	} // foreach port

	return (0);

} // main - scan