你在你的代码的几个错误:
connect()
成功返回0和1的错误。对于任何非零值,if
语句的计算结果为true。这意味着当connect()
出现故障时,您的代码正在发送CONNECT
消息。但是,并非所有的错误都是致命的。特别是,由于您使用的是非阻塞套接字,一个EINPROGRESS
/WSAEWOULDBLOCK
错误指示的连接仍然悬而未决,你需要使用select()
或(e)poll()
等待插座实际完成连接(或失败)。因此,只有当connect()
异步连接,并且恰好在您有机会致电send()
之前完全连接到代理服务器时,您的代码才会起作用。但这是你不应该依赖的行为。你需要正确处理错误。
的send()
的返回值指定多少字节实际上被接受,或者1的错误。可能会接受比请求更少的字节(尤其是在非阻塞套接字上)。并且您需要处理非致命错误,特别是在非Windows平台上的(WSA)EWOULDBLOCK
(和EAGAIN
,可能还有EINTR
),这意味着套接字在调用send()
时无法接受新数据,因此请再次调用send()
。您应该在循环中调用send()
,直到发送完所有字节,或发生致命错误。
即使您的数据是正确的send()
,您在strlen()
之后使用+ 1
也是错误的。您要在要发送的数据中包含空终止符,但这不是CONNECT
协议的一部分。空终止符将被代理视为应用程序数据,并将通过隧道原样转发到下一个服务器(如果隧道成功打开),从而中断与该服务器的通信。
说了这么多,试试更像下面的内容。您在使用closeocket()
表明你是Windows编程,所以这是针对Windows的:
int ret, err;
...
ret = connect(sock, pSockAddr, iSockAddrSize);
if (ret == -1)
{
err = WSAGetLastError();
if (err == WSAEWOULDBLOCK)
{
fd_set wfd;
FD_ZERO(&wfd);
FD_SET(sock, &wfd);
fd_set efd;
FD_ZERO(&efd);
FD_SET(sock, &efd);
timeval timeout;
timeout.tv_sec = ...;
timeout.tv_usec = ...;
ret = select(0, NULL, &wfd, &wfd, &timeout);
if (ret == 0)
{
printf("*J* Connect Timeout\n");
// handle timeout as needed ...
return;
}
if ((ret > 0) && FD_ISSET(sock, &efd))
{
err = 0;
getsockopt(sock, SOL_SOCKET, SO_ERROR, (char*)&err, sizeof(err));
ret = -1;
}
}
if (ret == -1)
{
printf("*J* Connect Failed: %d\n", err);
// handle fatal error as needed ...
return;
}
}
...
char message[80];
sprintf(message, "CONNECT 192.168.1.68:3001 HTTP/1.1\r\n\r\n");
printf("*J* Message loaded.\n"); //*J*
printf("*J* %s\n", message); //*J*
char *pmsg = message;
int len = strlen(message);
do
{
ret = send(sock, pmsg, len, 0);
if (ret == -1)
{
err = getLastSocketError();
if (err == WSAEWOULDBLOCK)
{
fd_set wfd;
FD_ZERO(&wfd);
FD_SET(sock, &wfd);
timeval timeout;
timeout.tv_sec = ...;
timeout.tv_usec = ...;
ret = select(0, NULL, &wfd, NULL, &timeout);
if (ret > 0)
continue;
if (ret == 0)
{
printf("*J* Send Timeout\n");
// handle timeout as needed ...
return;
}
err = WSAGetLastError();
}
printf("*J* Send Failed: %d\n", err);
// handle fatal error as needed ...
return;
}
else
{
pmsg += ret;
len += ret;
}
}
while (len > 0);
printf("*J* Data Sent\n");
...
printf("*J* Close Socket\n");
closesocket(sock);
如果你想要的东西多一点的跨平台,试试这个,而不是(或使用跨平台的套接字库代替) :
int getLastSocketError()
{
#ifdef WINDOWS
return WSAGetLastError();
#else
return errno;
#endif
};
int ret, err;
...
ret = connect(sock, pSockAddr, iSockAddrSize);
if (ret == -1)
{
err = getLastSocketError();
if (
#ifdef WINDOWS
err == WSAEWOULDBLOCK
#else
err == EINPROGRESS
#endif
)
{
#ifndef WINDOWS
do {
#endif
fd_set wfd;
FD_ZERO(&wfd);
FD_SET(sock, &wfd);
#ifdef WINDOWS
fd_set efd;
FD_ZERO(&efd);
FD_SET(sock, &efd);
#endif
timeval timeout;
timeout.tv_sec = ...;
timeout.tv_usec = ...;
#ifdef WINDOWS
ret = select(0, NULL, &wfd, &wfd, &timeout);
#else
ret = select(sock+1, NULL, &wfd, NULL, &timeout);
#endif
if (ret == 0)
{
printf("*J* Connect Timeout\n");
// handle timeout as needed ...
return;
}
#ifdef WINDOWS
if ((ret > 0) && FD_ISSET(sock, &efd))
{
err = 0;
getsockopt(sock, SOL_SOCKET, SO_ERROR, (char*)&err, sizeof(err));
ret = -1;
}
#endif
#ifndef WINDOWS
} while ((ret == -1) && (errno == EINTR));
#endif
}
if (ret == -1)
{
printf("*J* Connect Failed: %d\n", err);
// handle fatal error as needed ...
return;
}
}
...
char message[80];
sprintf(message, "CONNECT 192.168.1.68:3001 HTTP/1.1\r\n\r\n");
printf("*J* Message loaded.\n"); //*J*
printf("*J* %s\n", message); //*J*
char *pmsg = message;
int len = strlen(message);
do
{
ret = send(sock, pmsg, len, 0);
if (ret == -1)
{
err = getLastSocketError();
if (
#ifdef WINDOWS
err == WSAEWOULDBLOCK
#else
(err == EWOULDBLOCK) || (err == EAGAIN)
#endif
)
{
fd_set wfd;
FD_ZERO(&wfd);
FD_SET(sock, &wfd);
timeval timeout;
timeout.tv_sec = ...;
timeout.tv_usec = ...;
ret = select(
#ifdef WINDOWS
0
#else
sock+1
#endif
, NULL, &wfd, NULL, &timeout);
if (ret > 0)
continue;
if (ret == 0)
{
printf("*J* Send Timeout\n");
// handle timeout as needed ...
return;
}
err = getLastSocketError();
}
#ifndef WINDOWS
if (err != EINTR)
#endif
{
printf("*J* Send Failed: %d\n", err);
// handle fatal error as needed ...
return;
}
}
else
{
pmsg += ret;
len += ret;
}
}
while (len > 0);
printf("*J* Data Sent\n");
...
printf("*J* Close Socket\n");
#ifdef WINDOWS
closesocket(sock);
#else
close(sock);
#endif
发布您的代码并输出 – EsmaeelE
您是否在每次发送'CONNECT'命令后都读取代理的响应? – dbush
为什么这个'if(connect(sock,pSockAddr,iSockAddrSize))',而不是'if(connect(sock,pSockAddr,iSockAddrSize)!= -1)'? –