downloading a file

i have a problem that it alawys says that the server couldnt understand i dont rlly understand http protocol i quite got some of the picture by packet sniffing but i didnt acctually read the RFC

Code:

#include <stdio.h>
#include <windows.h>
#include <winsock.h>
#pragma comment( lib, "ws2_32" )
char *Http="http://www.google.com.com";
int Port = 80;//default port for http
void Send_Packet(SOCKET sock,char *packets, ... )//by a59 with lil touch by me
{
	char buffersize[400];

	va_list varagums;

	va_start( varagums, packets );

	vsprintf( buffersize, packets, varagums );
	
	va_end(varagums);

	send(sock,buffersize,strlen(buffersize),0);
}

int Setup_it()
{
	SOCKET http;
	SOCKADDR_IN Info;
	LPHOSTENT hostEntry;
	int error;

	/*Resolve it*/
	hostEntry=gethostbyname(Http);

	if(!hostEntry)
		return FALSE;
	//cr8 the socket
	http=socket(AF_INET,SOCK_STREAM,IPPROTO_TCP);
	if(http==INVALID_SOCKET)
		return FALSE;
	Info.sin_family = AF_INET;
	Info.sin_addr=*((LPIN_ADDR)*hostEntry->h_addr_list);
	Info.sin_port=htons(Port);
	
	error=connect(http,(SOCKADDR*)&Info,sizeof Info);
	if(error==INVALID_SOCKET)
		return FALSE;
	return http;
}
BOOL download_it()
{
	char path[100];
	char buffer[100]={0};
	FILE *fp;
	SOCKET http;
	http=Setup_it();
	if(!http) return FALSE;
	GetTempPath(sizeof path,path);
	fp=fopen(path,"w");
	Send_Packet(http,"GET /kosomack1234/exe.exe HTTP/1.1\r\n");
	Send_Packet(http,"Host: www.google.com\r\n");
	Send_Packet(http,"User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.0.5) Gecko/2008120122 Firefox/3.0.5\r\n");
	Send_Packet(http,"Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8\r\n");
	Send_Packet(http,"Accept-Language: en-us,en;q=0.5\r\n");
	Send_Packet(http,"Accept-Encoding: gzip,deflate\r\n");
	Send_Packet(http,"Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.7\r\n");
	Send_Packet(http,"Keep-Alive: 300\r\n");
	Send_Packet(http,"Connection: keep-alive\r\n");
	recv(http,buffer,sizeof buffer,0);
	puts(buffer);

}
int main(void)
{
	WSADATA Client;
	WSAStartup(MAKEWORD(2,2),&Client);
	download_it();
	return 0;
}

You need to send a double "\r\n" to indicate you are done sending the header. So you should have:

Code:

Send_Packet(http,"Connection: keep-alive\r\n\r\n");

oh thanks it says found now so what should i do to copy the file to my folder i fprintf buffer or what?

also shouldnt it put OK not Found in packets since when i download something my packet sniff says OK not Found ?

Originally Posted by elwad

also shouldnt it put OK not Found in packets since when i download something my packet sniff says OK not Found ?

English. Clear, comprehensible English. What exactly is your packet sniff showing?

On a successful request, the server's response will be much like a request. Several lines (separated with CRLF) of header information, a blank line, and then the actual body (which may be encoded). Something like:

Code:

HTTP/1.1 200 OK
Content-Type: image/png
Server: gws
Content-Length: 10000
(other lines)
(blank line)
(content)

Where each of those lines is terminated with a CRLF (\r\n).

HTTP/1.1 302 Found
Date: Wed, 03 Jun 2009 08:20:48 GMT
Server: Apache
Content-Length: 0
Connection: close
Content-Type: text/html; charset=UTF-8

i dont Get OK

Originally Posted by elwad

i dont Get OK

Then read the RFC. Don't expect other people to "tell you along the way". HTTP 302 is often used for redirections. I doubt that "/kosomack1234/exe.exe" actually exists at google.com.

i thought that would get the html of it

I don't do this that much, but the only line I send is this one:

Code:

Send_Packet(http,"GET /kosomack1234/exe.exe HTTP/1.1\r\n\r\n");

with two \r\n's on the end*, none of the rest of the optional stuff ("user-agent", etc) and it always seems to work (except when you need to pose as a specific user agent).

Have you tried with a different server and file? Try to grab just a normal html page or an image somewhere...

*and I say HTTP/1.0, if that matters

yah i did with one manga it worked but without double \r\n in the GET when i added them it said bad request

Code:

#include <stdio.h>
#include <windows.h>
#include <winsock.h>
#pragma comment( lib, "ws2_32" )
char *Http="http://www.onemanga.com/";
int Port = 80;//default port for http
void Send_Packet(SOCKET sock,char *packets, ... )//by a59 with lil touch by me
{
	char buffersize[400];

	va_list varagums;

	va_start( varagums, packets );

	vsprintf( buffersize, packets, varagums );
	
	va_end(varagums);

	send(sock,buffersize,strlen(buffersize),0);
}

int Setup_it()
{
	SOCKET http;
	SOCKADDR_IN Info;
	LPHOSTENT hostEntry;
	int error;

	/*Resolve it*/
	hostEntry=gethostbyname(Http);

	if(!hostEntry)
		return FALSE;
	//cr8 the socket
	http=socket(AF_INET,SOCK_STREAM,IPPROTO_TCP);
	if(http==INVALID_SOCKET)
		return FALSE;
	Info.sin_family = AF_INET;
	Info.sin_addr=*((LPIN_ADDR)*hostEntry->h_addr_list);
	Info.sin_port=htons(Port);
	
	error=connect(http,(SOCKADDR*)&Info,sizeof Info);
	if(error==INVALID_SOCKET)
		return FALSE;
	return http;
}
BOOL download_it()
{
	char path[100];
	char buffer[100]={0};
	FILE *fp;
	SOCKET http;
	http=Setup_it();
	if(!http) return FALSE;
	GetTempPath(sizeof path,path);
	strcat(path,"\\exe.exe");
	fp=fopen(path,"w");

	Send_Packet(http,"GET /html HTTP/1.1\r\n"
	                 "Host: www.onemanga.com\r\n"
					 "User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.0.5) Gecko/2008120122 Firefox/3.0.5\r\n"
					 "Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8\r\n"
					 "Accept-Language: en-us,en;q=0.5\r\n"
					 "Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.7\r\n"
					 "Keep-Alive: 300\r\n"
					 "Connection: keep-alive\r\n\r\n"/*needed to send double one to indicate that i m finished sending the header*/
					 );
	
	recv(http,buffer,sizeof buffer,0);

	puts(buffer);


	return TRUE;
}
int main(void)
{
	WSADATA Client;
	WSAStartup(MAKEWORD(2,2),&Client);
	download_it();
	return 0;
}

Originally Posted by elwad

yah i did with one manga it worked but without double \r\n in the GET when i added them it said bad request

Okay. I saw your note about putting the double /r/n at the end, I had forgotten the reason for that. My point is that in my (limited) experience, you do not have to send more than just the one line with GET in it. Getting rid of the unnecessary stuff will eliminate the possibility that it is that which is causing the problem.

i m srry to ask this i know i should read RFC and all but wanted to ask whats most important information i need to send to download a File instead of just sending random stuff i saw in my packet sniffer...

Originally Posted by elwad

i m srry to ask this i know i should read RFC and all but wanted to ask whats most important information i need to send to download a File instead of just sending random stuff i saw in my packet sniffer...

Like I said in post #10, AFAIK you only have to send one line (the one with GET in it). Some servers may want more (eg, some of them will only accept certain user-agents) but *most* of them do not.

If you are getting a response like you said earlier, even if it is an error (file not found) your request has been correctly received and processed.

I just downloaded this (using just a one line GET), so the address works, try it:

http://www.cearta.ie/wp-content/uplo...ello_world.png

Originally Posted by MK27

Like I said in post #10, AFAIK you only have to send one line (the one with GET in it). Some servers may want more (eg, some of them will only accept certain user-agents) but *most* of them do not.

If any server is letting you get away with 1 line requests, then shame on it - such a request is invalid. At the very minimum, you must specify a Host header. Ie:

Code:

GET / HTTP/1.1
Host: whoever.com

Further to your example, you did? What exactly did you send:

Code:

GET /wp-content/uploads/2006/hello_world.png HTTP/1.1

HTTP/1.1 400 Bad Request
...

You're getting a 302 - it's essentially a "it's over here" response. You'll have to send another request with a different URI. Reading the RFC:

Originally Posted by HTTP

10.3.3 302 Found

The requested resource resides temporarily under a different URI.
Since the redirection might be altered on occasion, the client SHOULD
continue to use the Request-URI for future requests. This response
is only cacheable if indicated by a Cache-Control or Expires header
field.

The temporary URI SHOULD be given by the Location field in the
response. Unless the request method was HEAD, the entity of the
response SHOULD contain a short hypertext note with a hyperlink to
the new URI(s).

If the 302 status code is received in response to a request other
than GET or HEAD, the user agent MUST NOT automatically redirect the
request unless it can be confirmed by the user, since this might
change the conditions under which the request was issued.

Note: RFC 1945 and RFC 2068 specify that the client is not allowed
to change the method on the redirected request. However, most
existing user agent implementations treat 302 as if it were a 303
response, performing a GET on the Location field-value regardless
of the original request method. The status codes 303 and 307 have
been added for servers that wish to make unambiguously clear which
kind of reaction is expected of the client.

Additionally, your network code is poor. You need to loop that recv() until you have _all_ of the data. Have I mentioned yet that there are spiffy libraries that do all of this... like libcurl?