Question

我正在开发一个小项目（C编程）来隧道通过代理，当我尝试这样做时，我收到一个错误：

HTTP/1.0 400 Bad Request
Server: squid/2.7.STABLE9
Date: Mon, 07 Jan 2013 22:20:56 GMT
Content-Type: text/html 
Content-Length: 1456
X-Squid-Error: ERR_INVALID_REQ 0
X-Cache: MISS from xt03
Via: 1.0 xt03:80 (squid/2.7.STABLE9)
Connection: close

我发送给代理服务器的数据是：

 char msg[] = "CONNECT example.com:80 HTTP/1.0 <CR><LF> HOST example.com:80 <CR><LF> \n";

任何帮助都会很棒！

------更新------

我尝试了你们建议的方法，但我仍然遇到错误。我将发布我的整个代码集，看看它是否在套接字中导致它发送错误的信息。

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <arpa/inet.h>
#include <netinet/in.h>

#define maxlen 2048

int main(int argc, char *argv[])
{
int mysocket;
int len;
char buffer[2000];
char msg[] = "CONNECT example.org:80 HTTP/1.0 \r\n HOST example.org:80 \r\n\r\n";


mysocket = socket(AF_INET, SOCK_STREAM, 0);

struct sockaddr_in dest;

memset(&dest, 0, sizeof(dest));

dest.sin_family = AF_INET;
dest.sin_addr.s_addr = inet_addr("125.39.66.150");
dest.sin_port = htons(80);

connect(mysocket, (struct sockaddr *)&dest, sizeof(struct sockaddr));

send(mysocket, msg, strlen(msg), 0);
len = recv(mysocket, buffer, maxlen, 0);

buffer[len] = '\0';

printf("%s \n", buffer);
close(mysocket);
return 0;

}

-----更新------

新错误：

HTTP/1.0 400 Bad Request
Server: squid/2.7.STABLE5
Date: Tue, 08 Jan 2013 22:40:24 GMT
Content-Type: text/html
Content-Length: 1158
X-Squid-Error: ERR_INVALID_REQ 0
X-Cache: MISS from DXT-BJ-219
X-Cache-Lookup: NONE from DXT-BJ-219:80
Connection: close

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"         "http://www.w3.org/TR/html4/loose.dtd">
<HTML><HEAD><META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=iso-8859-1">
<TITLE>ERROR: The requested URL could not be retrieved</TITLE>
<STYLE type="text/css"><!--BODY{background-color:#ffffff;font-family:verdana,sans-    serif}PRE{font-family:sans-serif}--></STYLE>
</HEAD><BODY>
<H1>ERROR</H1>
<H2>The requested URL could not be retrieved</H2>
<HR noshade size="1px">
<P> 
While trying to process the request:
<PRE>
CONNECT example.com:80 HTTP/1.1


</PRE>
<P>
The following error was encountered:
<UL>
<LI>
<STRONG>
Invalid Request
</STRONG>
</UL>

<P>
Some aspect of the HTTP Request is invalid.  Possible problems:
<UL>
<LI>Missing or unknown request method
<LI>Missing URL
<LI>Missing HTTP Identifier (HTTP/1.0)
<LI>Request is too large
<LI>Content-Length missing for POST or PUT requests
<LI>Illegal character in hostname; underscores are not allowed
</UL>
<P>Your cache administrator is <A HREF="mailto:noc_admin@163.com">noc_admin@163.com</A>. 

<BR clear="all">
<HR noshade size="1px">
<ADDRESS>
by DXT-BJ-219
</ADDRESS>
</BODY></HTML>

Answer 1

“错误请求”表示您发送到服务器的请求格式错误且无法理解。我认为这样做的原因是你发送 8 字符<CR><LF>（如'，'＆lt;'，'C'，'R'等）而不是2个字符他们应该代表，即\r\n。

尝试

char msg[] = "CONNECT example.com:80 HTTP/1.0\r\nHOST example:80\r\n\r\n";

Answer 2

请参阅：rfc2616

10.4.1 400错误请求

由于语法格式错误，服务器无法理解该请求。客户端不应该在没有修改的情况下重复请求。

当你通过时：

char msg[] = "CONNECT example.com:80 HTTP/1.0 <CR><LF> HOST example.com:80 <CR><LF> \n";

然后，<CR>和<LF>部分可能会以字符串形式发送，而不是ASCII 0xA和0xD，它们代表您要发送的控制字符。最简单的解决方法是使用C等价物：\r <CR>和\n <LF>：

char msg[] = "CONNECT example.com:80 HTTP/1.0 \r\n HOST example.com:80 \r\n\r\n";

如果您打算扩展msg[]数组的使用以包含更多请求，则可能必须编写包装函数以将msg[]中的CR，LF和其他控制字符串转换为适当的C char等同于形成正确的信息。

希望这有帮助。

代理隧道与c

2 个答案: