static void Main(string[] args)
{
System.Console.Write("Enter a URL address:");
string url = System.Console.ReadLine();
System.Console.WriteLine("Scanning hyperlinks at: " + url);
string page;
if (url.StartsWith("http://", StringComparison.OrdinalIgnoreCase))
{
page = GetPage(url);
}
else
{
page = ReadFile(url);
}
if (page == null)
{
System.Console.WriteLine("Can't process that type of file,"
+
"please specify an HTML file URL."
);
return;
}
ParseHTML parse = new ParseHTML();
parse.Source = page;
while (!parse.Eof())
{
char ch = parse.Parse();
if (ch == 0)
{
AttributeList tag = parse.GetTag();
if (tag["href"] != null)
{
System.Console.WriteLine("Found link: " +
tag["href"].Value);
}
}
}
}
void IHttpHandler.ProcessRequest(HttpContext Context)
{
string ServerURL = "";
string ext = ".tunnel";
string protocol = "http://";
try
{
// Parsing incoming URL and extracting original server URL
char[] URL_Separator = { '/' };
string[] URL_List = Context.Request.Url.AbsoluteUri.Remove(0, protocol.Length).Split(URL_Separator);
ServerURL = protocol + URL_List[2].Remove(URL_List[2].Length - ext.Length, ext.Length) + @"/";
string URLPrefix = @"/" + URL_List[1] + @"/" + URL_List[2]; // Eg. "/handler/stg2web.tunnel";
for ( int i = 3; i < URL_List.Length; i++ )
{
ServerURL += URL_List[i] + @"/";
}
ServerURL = ServerURL.Remove(ServerURL.Length -1, 1);
WriteLog(ServerURL + " (" + Context.Request.Url.ToString() + ")");
// Extracting POST data from incoming request
Stream RequestStream = Context.Request.InputStream;
byte[] PostData = new byte[Context.Request.InputStream.Length];
RequestStream.Read(PostData, 0, (int) Context.Request.InputStream.Length);
// Creating proxy web request
HttpWebRequest ProxyRequest = (HttpWebRequest) WebRequest.Create(ServerURL);
if (false)
{
ProxyRequest.Proxy = new WebProxy("proxy1:80", true);
}
ProxyRequest.Method = Context.Request.HttpMethod;
ProxyRequest.UserAgent = Context.Request.UserAgent;
CookieContainer ProxyCookieContainer = new CookieContainer();
ProxyRequest.CookieContainer = new CookieContainer();
ProxyRequest.CookieContainer.Add(ProxyCookieContainer.GetCookies(new Uri(ServerURL)));
ProxyRequest.KeepAlive = true;
// For POST, write the post data extracted from the incoming request
if (ProxyRequest.Method == "POST")
{
ProxyRequest.ContentType = "application/x-www-form-urlencoded";
ProxyRequest.ContentLength = PostData.Length;
Stream ProxyRequestStream = ProxyRequest.GetRequestStream();
ProxyRequestStream.Write(PostData, 0, PostData.Length);
ProxyRequestStream.Close();
}
// Getting response from the proxy request
HttpWebResponse ProxyResponse = (HttpWebResponse) ProxyRequest.GetResponse();
if (ProxyRequest.HaveResponse)
{
// Handle cookies
foreach(Cookie ReturnCookie in ProxyResponse.Cookies)
{
bool CookieFound = false;
foreach(Cookie OldCookie in ProxyCookieContainer.GetCookies(new Uri(ServerURL)))
{
if (ReturnCookie.Name.Equals(OldCookie.Name))
{
OldCookie.Value = ReturnCookie.Value;
CookieFound = true;
}
}
if (!CookieFound)
{
ProxyCookieContainer.Add(ReturnCookie);
}
}
}
Stream StreamResponse = ProxyResponse.GetResponseStream();
int ResponseReadBufferSize = 256;
byte[] ResponseReadBuffer = new byte[ResponseReadBufferSize];
MemoryStream MemoryStreamResponse = new MemoryStream();
int ResponseCount = StreamResponse.Read(ResponseReadBuffer, 0, ResponseReadBufferSize);
while ( ResponseCount > 0 )
{
MemoryStreamResponse.Write(ResponseReadBuffer, 0, ResponseCount);
ResponseCount = StreamResponse.Read(ResponseReadBuffer, 0, ResponseReadBufferSize);
}
byte[] ResponseData = MemoryStreamResponse.ToArray();
string ResponseDataString = Encoding.ASCII.GetString(ResponseData);
Context.Response.ContentType = ProxyResponse.ContentType;
// While rendering HTML, parse and modify the URLs present
if (ProxyResponse.ContentType.StartsWith("text/html"))
{
HTML.ParseHTML Parser = new HTML.ParseHTML();
Parser.Source = ResponseDataString;
while (!Parser.Eof())
{
char ch = Parser.Parse();
if (ch == 0)
{
HTML.AttributeList Tag = Parser.GetTag();
if (Tag.Name.Equals("img", StringComparison.InvariantCultureIgnoreCase))
{
// Adjust image tags
}
if (Tag["href"] != null)
{
if (Tag["href"].Value.StartsWith(@"/"))
{
WriteLog("URL " + Tag["href"].Value + " modified to " + URLPrefix + Tag["href"].Value);
ResponseDataString = ResponseDataString.Replace(
"\"" + Tag["href"].Value + "\"",
"\"" + URLPrefix + Tag["href"].Value + "\"");
}
}
if (Tag["src"] != null)
{
if (Tag["src"].Value.StartsWith(@"/"))
{
WriteLog("URL " + Tag["src"].Value + " modified to " + URLPrefix + Tag["src"].Value);
ResponseDataString = ResponseDataString.Replace(
"\"" + Tag["src"].Value + "\"",
"\"" + URLPrefix + Tag["src"].Value + "\"");
}
}
}
}
// Replace script/style file url's
ResponseDataString = ResponseDataString.Replace(
"url('/",
"url('" + URLPrefix + "/");
// replace flash file url's
ResponseDataString = ResponseDataString.Replace(
"swf: '/",
"swf: '" + URLPrefix + "/");
Context.Response.Write(ResponseDataString);
}
else
{
Context.Response.OutputStream.Write(ResponseData, 0, ResponseData.Length);
}
MemoryStreamResponse.Close();
StreamResponse.Close();
ProxyResponse.Close();
}
catch (Exception Ex)
{
Context.Response.Write(Ex.Message.ToString());
WriteLog("An error has occurred while requesting the URL " +
ServerURL + "(" + Context.Request.Url.ToString() + ")\n" +
Ex.ToString());
}
}
private static string ParsePageForImage(string page)
{
ParseHTML parse = new ParseHTML();
parse.Source = page;
while (!parse.Eof())
{
char ch = parse.Parse();
if (ch == 0)
{
AttributeList tag = parse.GetTag();
if (tag["src"] != null && tag.Name == "img" && tag["src"].Value.Contains("scans"))
{
return tag["src"].Value;
}
}
}
return "";
}
