804 lines
		
	
	
		
			26 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			804 lines
		
	
	
		
			26 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /***************************************************************************
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|  *                                  _   _ ____  _
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|  *  Project                     ___| | | |  _ \| |
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|  *                             / __| | | | |_) | |
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|  *                            | (__| |_| |  _ <| |___
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|  *                             \___|\___/|_| \_\_____|
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|  *
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|  * Copyright (C) 1998 - 2019, Daniel Stenberg, <daniel@haxx.se>, et al.
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|  *
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|  * This software is licensed as described in the file COPYING, which
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|  * you should have received as part of this distribution. The terms
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|  * are also available at https://curl.haxx.se/docs/copyright.html.
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|  *
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|  * You may opt to use, copy, modify, merge, publish, distribute and/or sell
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|  * copies of the Software, and permit persons to whom the Software is
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|  * furnished to do so, under the terms of the COPYING file.
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|  *
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|  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
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|  * KIND, either express or implied.
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|  *
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|  ***************************************************************************/
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| 
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| #include "curl_setup.h"
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| 
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| #if !defined(CURL_DISABLE_PROXY)
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| 
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| #ifdef HAVE_NETINET_IN_H
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| #include <netinet/in.h>
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| #endif
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| #ifdef HAVE_ARPA_INET_H
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| #include <arpa/inet.h>
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| #endif
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| 
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| #include "urldata.h"
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| #include "sendf.h"
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| #include "select.h"
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| #include "connect.h"
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| #include "timeval.h"
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| #include "socks.h"
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| 
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| /* The last #include file should be: */
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| #include "memdebug.h"
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| 
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| /*
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|  * Helper read-from-socket functions. Does the same as Curl_read() but it
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|  * blocks until all bytes amount of buffersize will be read. No more, no less.
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|  *
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|  * This is STUPID BLOCKING behaviour which we frown upon, but right now this
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|  * is what we have...
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|  */
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| int Curl_blockread_all(struct connectdata *conn, /* connection data */
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|                        curl_socket_t sockfd,     /* read from this socket */
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|                        char *buf,                /* store read data here */
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|                        ssize_t buffersize,       /* max amount to read */
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|                        ssize_t *n)               /* amount bytes read */
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| {
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|   ssize_t nread = 0;
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|   ssize_t allread = 0;
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|   int result;
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|   *n = 0;
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|   for(;;) {
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|     timediff_t timeleft = Curl_timeleft(conn->data, NULL, TRUE);
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|     if(timeleft < 0) {
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|       /* we already got the timeout */
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|       result = CURLE_OPERATION_TIMEDOUT;
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|       break;
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|     }
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|     if(SOCKET_READABLE(sockfd, timeleft) <= 0) {
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|       result = ~CURLE_OK;
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|       break;
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|     }
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|     result = Curl_read_plain(sockfd, buf, buffersize, &nread);
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|     if(CURLE_AGAIN == result)
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|       continue;
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|     if(result)
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|       break;
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| 
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|     if(buffersize == nread) {
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|       allread += nread;
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|       *n = allread;
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|       result = CURLE_OK;
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|       break;
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|     }
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|     if(!nread) {
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|       result = ~CURLE_OK;
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|       break;
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|     }
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| 
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|     buffersize -= nread;
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|     buf += nread;
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|     allread += nread;
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|   }
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|   return result;
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| }
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| 
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| /*
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| * This function logs in to a SOCKS4 proxy and sends the specifics to the final
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| * destination server.
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| *
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| * Reference :
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| *   https://www.openssh.com/txt/socks4.protocol
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| *
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| * Note :
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| *   Set protocol4a=true for  "SOCKS 4A (Simple Extension to SOCKS 4 Protocol)"
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| *   Nonsupport "Identification Protocol (RFC1413)"
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| */
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| CURLcode Curl_SOCKS4(const char *proxy_user,
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|                      const char *hostname,
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|                      int remote_port,
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|                      int sockindex,
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|                      struct connectdata *conn)
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| {
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|   const bool protocol4a =
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|     (conn->socks_proxy.proxytype == CURLPROXY_SOCKS4A) ? TRUE : FALSE;
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| #define SOCKS4REQLEN 262
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|   unsigned char socksreq[SOCKS4REQLEN]; /* room for SOCKS4 request incl. user
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|                                            id */
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|   CURLcode code;
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|   curl_socket_t sock = conn->sock[sockindex];
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|   struct Curl_easy *data = conn->data;
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| 
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|   if(Curl_timeleft(data, NULL, TRUE) < 0) {
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|     /* time-out, bail out, go home */
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|     failf(data, "Connection time-out");
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|     return CURLE_OPERATION_TIMEDOUT;
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|   }
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| 
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|   if(conn->bits.httpproxy)
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|     infof(conn->data, "SOCKS4%s: connecting to HTTP proxy %s port %d\n",
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|           protocol4a ? "a" : "", hostname, remote_port);
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| 
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|   (void)curlx_nonblock(sock, FALSE);
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| 
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|   infof(data, "SOCKS4 communication to %s:%d\n", hostname, remote_port);
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| 
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|   /*
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|    * Compose socks4 request
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|    *
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|    * Request format
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|    *
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|    *     +----+----+----+----+----+----+----+----+----+----+....+----+
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|    *     | VN | CD | DSTPORT |      DSTIP        | USERID       |NULL|
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|    *     +----+----+----+----+----+----+----+----+----+----+....+----+
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|    * # of bytes:  1    1      2              4           variable       1
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|    */
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| 
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|   socksreq[0] = 4; /* version (SOCKS4) */
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|   socksreq[1] = 1; /* connect */
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|   socksreq[2] = (unsigned char)((remote_port >> 8) & 0xff); /* PORT MSB */
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|   socksreq[3] = (unsigned char)(remote_port & 0xff);        /* PORT LSB */
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| 
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|   /* DNS resolve only for SOCKS4, not SOCKS4a */
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|   if(!protocol4a) {
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|     struct Curl_dns_entry *dns;
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|     Curl_addrinfo *hp = NULL;
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|     int rc;
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| 
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|     rc = Curl_resolv(conn, hostname, remote_port, FALSE, &dns);
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| 
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|     if(rc == CURLRESOLV_ERROR)
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|       return CURLE_COULDNT_RESOLVE_PROXY;
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| 
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|     if(rc == CURLRESOLV_PENDING)
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|       /* ignores the return code, but 'dns' remains NULL on failure */
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|       (void)Curl_resolver_wait_resolv(conn, &dns);
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| 
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|     /*
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|      * We cannot use 'hostent' as a struct that Curl_resolv() returns.  It
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|      * returns a Curl_addrinfo pointer that may not always look the same.
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|      */
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|     if(dns)
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|       hp = dns->addr;
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|     if(hp) {
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|       char buf[64];
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|       Curl_printable_address(hp, buf, sizeof(buf));
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| 
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|       if(hp->ai_family == AF_INET) {
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|         struct sockaddr_in *saddr_in;
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| 
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|         saddr_in = (struct sockaddr_in *)(void *)hp->ai_addr;
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|         socksreq[4] = ((unsigned char *)&saddr_in->sin_addr.s_addr)[0];
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|         socksreq[5] = ((unsigned char *)&saddr_in->sin_addr.s_addr)[1];
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|         socksreq[6] = ((unsigned char *)&saddr_in->sin_addr.s_addr)[2];
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|         socksreq[7] = ((unsigned char *)&saddr_in->sin_addr.s_addr)[3];
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| 
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|         infof(data, "SOCKS4 connect to IPv4 %s (locally resolved)\n", buf);
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|       }
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|       else {
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|         hp = NULL; /* fail! */
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| 
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|         failf(data, "SOCKS4 connection to %s not supported\n", buf);
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|       }
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| 
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|       Curl_resolv_unlock(data, dns); /* not used anymore from now on */
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|     }
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|     if(!hp) {
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|       failf(data, "Failed to resolve \"%s\" for SOCKS4 connect.",
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|             hostname);
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|       return CURLE_COULDNT_RESOLVE_HOST;
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|     }
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|   }
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| 
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|   /*
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|    * This is currently not supporting "Identification Protocol (RFC1413)".
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|    */
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|   socksreq[8] = 0; /* ensure empty userid is NUL-terminated */
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|   if(proxy_user) {
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|     size_t plen = strlen(proxy_user);
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|     if(plen >= sizeof(socksreq) - 8) {
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|       failf(data, "Too long SOCKS proxy name, can't use!\n");
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|       return CURLE_COULDNT_CONNECT;
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|     }
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|     /* copy the proxy name WITH trailing zero */
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|     memcpy(socksreq + 8, proxy_user, plen + 1);
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|   }
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| 
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|   /*
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|    * Make connection
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|    */
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|   {
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|     int result;
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|     ssize_t actualread;
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|     ssize_t written;
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|     ssize_t hostnamelen = 0;
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|     ssize_t packetsize = 9 +
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|       strlen((char *)socksreq + 8); /* size including NUL */
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| 
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|     /* If SOCKS4a, set special invalid IP address 0.0.0.x */
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|     if(protocol4a) {
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|       socksreq[4] = 0;
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|       socksreq[5] = 0;
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|       socksreq[6] = 0;
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|       socksreq[7] = 1;
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|       /* If still enough room in buffer, also append hostname */
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|       hostnamelen = (ssize_t)strlen(hostname) + 1; /* length including NUL */
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|       if(packetsize + hostnamelen <= SOCKS4REQLEN)
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|         strcpy((char *)socksreq + packetsize, hostname);
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|       else
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|         hostnamelen = 0; /* Flag: hostname did not fit in buffer */
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|     }
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| 
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|     /* Send request */
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|     code = Curl_write_plain(conn, sock, (char *)socksreq,
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|                             packetsize + hostnamelen,
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|                             &written);
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|     if(code || (written != packetsize + hostnamelen)) {
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|       failf(data, "Failed to send SOCKS4 connect request.");
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|       return CURLE_COULDNT_CONNECT;
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|     }
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|     if(protocol4a && hostnamelen == 0) {
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|       /* SOCKS4a with very long hostname - send that name separately */
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|       hostnamelen = (ssize_t)strlen(hostname) + 1;
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|       code = Curl_write_plain(conn, sock, (char *)hostname, hostnamelen,
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|                               &written);
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|       if(code || (written != hostnamelen)) {
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|         failf(data, "Failed to send SOCKS4 connect request.");
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|         return CURLE_COULDNT_CONNECT;
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|       }
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|     }
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| 
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|     packetsize = 8; /* receive data size */
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| 
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|     /* Receive response */
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|     result = Curl_blockread_all(conn, sock, (char *)socksreq, packetsize,
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|                                 &actualread);
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|     if(result || (actualread != packetsize)) {
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|       failf(data, "Failed to receive SOCKS4 connect request ack.");
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|       return CURLE_COULDNT_CONNECT;
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|     }
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| 
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|     /*
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|      * Response format
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|      *
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|      *     +----+----+----+----+----+----+----+----+
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|      *     | VN | CD | DSTPORT |      DSTIP        |
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|      *     +----+----+----+----+----+----+----+----+
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|      * # of bytes:  1    1      2              4
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|      *
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|      * VN is the version of the reply code and should be 0. CD is the result
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|      * code with one of the following values:
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|      *
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|      * 90: request granted
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|      * 91: request rejected or failed
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|      * 92: request rejected because SOCKS server cannot connect to
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|      *     identd on the client
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|      * 93: request rejected because the client program and identd
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|      *     report different user-ids
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|      */
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| 
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|     /* wrong version ? */
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|     if(socksreq[0] != 0) {
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|       failf(data,
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|             "SOCKS4 reply has wrong version, version should be 0.");
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|       return CURLE_COULDNT_CONNECT;
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|     }
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| 
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|     /* Result */
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|     switch(socksreq[1]) {
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|     case 90:
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|       infof(data, "SOCKS4%s request granted.\n", protocol4a?"a":"");
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|       break;
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|     case 91:
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|       failf(data,
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|             "Can't complete SOCKS4 connection to %d.%d.%d.%d:%d. (%d)"
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|             ", request rejected or failed.",
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|             (unsigned char)socksreq[4], (unsigned char)socksreq[5],
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|             (unsigned char)socksreq[6], (unsigned char)socksreq[7],
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|             (((unsigned char)socksreq[2] << 8) | (unsigned char)socksreq[3]),
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|             (unsigned char)socksreq[1]);
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|       return CURLE_COULDNT_CONNECT;
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|     case 92:
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|       failf(data,
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|             "Can't complete SOCKS4 connection to %d.%d.%d.%d:%d. (%d)"
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|             ", request rejected because SOCKS server cannot connect to "
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|             "identd on the client.",
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|             (unsigned char)socksreq[4], (unsigned char)socksreq[5],
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|             (unsigned char)socksreq[6], (unsigned char)socksreq[7],
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|             (((unsigned char)socksreq[2] << 8) | (unsigned char)socksreq[3]),
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|             (unsigned char)socksreq[1]);
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|       return CURLE_COULDNT_CONNECT;
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|     case 93:
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|       failf(data,
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|             "Can't complete SOCKS4 connection to %d.%d.%d.%d:%d. (%d)"
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|             ", request rejected because the client program and identd "
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|             "report different user-ids.",
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|             (unsigned char)socksreq[4], (unsigned char)socksreq[5],
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|             (unsigned char)socksreq[6], (unsigned char)socksreq[7],
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|             (((unsigned char)socksreq[2] << 8) | (unsigned char)socksreq[3]),
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|             (unsigned char)socksreq[1]);
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|       return CURLE_COULDNT_CONNECT;
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|     default:
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|       failf(data,
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|             "Can't complete SOCKS4 connection to %d.%d.%d.%d:%d. (%d)"
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|             ", Unknown.",
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|             (unsigned char)socksreq[4], (unsigned char)socksreq[5],
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|             (unsigned char)socksreq[6], (unsigned char)socksreq[7],
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|             (((unsigned char)socksreq[2] << 8) | (unsigned char)socksreq[3]),
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|             (unsigned char)socksreq[1]);
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|       return CURLE_COULDNT_CONNECT;
 | |
|     }
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|   }
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| 
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|   (void)curlx_nonblock(sock, TRUE);
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| 
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|   return CURLE_OK; /* Proxy was successful! */
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| }
 | |
| 
 | |
| /*
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|  * This function logs in to a SOCKS5 proxy and sends the specifics to the final
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|  * destination server.
 | |
|  */
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| CURLcode Curl_SOCKS5(const char *proxy_user,
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|                      const char *proxy_password,
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|                      const char *hostname,
 | |
|                      int remote_port,
 | |
|                      int sockindex,
 | |
|                      struct connectdata *conn)
 | |
| {
 | |
|   /*
 | |
|     According to the RFC1928, section "6.  Replies". This is what a SOCK5
 | |
|     replies:
 | |
| 
 | |
|         +----+-----+-------+------+----------+----------+
 | |
|         |VER | REP |  RSV  | ATYP | BND.ADDR | BND.PORT |
 | |
|         +----+-----+-------+------+----------+----------+
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|         | 1  |  1  | X'00' |  1   | Variable |    2     |
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|         +----+-----+-------+------+----------+----------+
 | |
| 
 | |
|     Where:
 | |
| 
 | |
|     o  VER    protocol version: X'05'
 | |
|     o  REP    Reply field:
 | |
|     o  X'00' succeeded
 | |
|   */
 | |
| 
 | |
|   unsigned char socksreq[600]; /* room for large user/pw (255 max each) */
 | |
|   int idx;
 | |
|   ssize_t actualread;
 | |
|   ssize_t written;
 | |
|   int result;
 | |
|   CURLcode code;
 | |
|   curl_socket_t sock = conn->sock[sockindex];
 | |
|   struct Curl_easy *data = conn->data;
 | |
|   timediff_t timeout;
 | |
|   bool socks5_resolve_local =
 | |
|     (conn->socks_proxy.proxytype == CURLPROXY_SOCKS5) ? TRUE : FALSE;
 | |
|   const size_t hostname_len = strlen(hostname);
 | |
|   ssize_t len = 0;
 | |
|   const unsigned long auth = data->set.socks5auth;
 | |
|   bool allow_gssapi = FALSE;
 | |
| 
 | |
|   if(conn->bits.httpproxy)
 | |
|     infof(conn->data, "SOCKS5: connecting to HTTP proxy %s port %d\n",
 | |
|           hostname, remote_port);
 | |
| 
 | |
|   /* RFC1928 chapter 5 specifies max 255 chars for domain name in packet */
 | |
|   if(!socks5_resolve_local && hostname_len > 255) {
 | |
|     infof(conn->data, "SOCKS5: server resolving disabled for hostnames of "
 | |
|           "length > 255 [actual len=%zu]\n", hostname_len);
 | |
|     socks5_resolve_local = TRUE;
 | |
|   }
 | |
| 
 | |
|   /* get timeout */
 | |
|   timeout = Curl_timeleft(data, NULL, TRUE);
 | |
| 
 | |
|   if(timeout < 0) {
 | |
|     /* time-out, bail out, go home */
 | |
|     failf(data, "Connection time-out");
 | |
|     return CURLE_OPERATION_TIMEDOUT;
 | |
|   }
 | |
| 
 | |
|   (void)curlx_nonblock(sock, TRUE);
 | |
| 
 | |
|   /* wait until socket gets connected */
 | |
|   result = SOCKET_WRITABLE(sock, timeout);
 | |
| 
 | |
|   if(-1 == result) {
 | |
|     failf(conn->data, "SOCKS5: no connection here");
 | |
|     return CURLE_COULDNT_CONNECT;
 | |
|   }
 | |
|   if(0 == result) {
 | |
|     failf(conn->data, "SOCKS5: connection timeout");
 | |
|     return CURLE_OPERATION_TIMEDOUT;
 | |
|   }
 | |
| 
 | |
|   if(result & CURL_CSELECT_ERR) {
 | |
|     failf(conn->data, "SOCKS5: error occurred during connection");
 | |
|     return CURLE_COULDNT_CONNECT;
 | |
|   }
 | |
| 
 | |
|   if(auth & ~(CURLAUTH_BASIC | CURLAUTH_GSSAPI))
 | |
|     infof(conn->data,
 | |
|         "warning: unsupported value passed to CURLOPT_SOCKS5_AUTH: %lu\n",
 | |
|         auth);
 | |
|   if(!(auth & CURLAUTH_BASIC))
 | |
|     /* disable username/password auth */
 | |
|     proxy_user = NULL;
 | |
| #if defined(HAVE_GSSAPI) || defined(USE_WINDOWS_SSPI)
 | |
|   if(auth & CURLAUTH_GSSAPI)
 | |
|     allow_gssapi = TRUE;
 | |
| #endif
 | |
| 
 | |
|   idx = 0;
 | |
|   socksreq[idx++] = 5;   /* version */
 | |
|   idx++;                 /* reserve for the number of authentication methods */
 | |
|   socksreq[idx++] = 0;   /* no authentication */
 | |
|   if(allow_gssapi)
 | |
|     socksreq[idx++] = 1; /* GSS-API */
 | |
|   if(proxy_user)
 | |
|     socksreq[idx++] = 2; /* username/password */
 | |
|   /* write the number of authentication methods */
 | |
|   socksreq[1] = (unsigned char) (idx - 2);
 | |
| 
 | |
|   (void)curlx_nonblock(sock, FALSE);
 | |
| 
 | |
|   infof(data, "SOCKS5 communication to %s:%d\n", hostname, remote_port);
 | |
| 
 | |
|   code = Curl_write_plain(conn, sock, (char *)socksreq, (2 + (int)socksreq[1]),
 | |
|                           &written);
 | |
|   if(code || (written != (2 + (int)socksreq[1]))) {
 | |
|     failf(data, "Unable to send initial SOCKS5 request.");
 | |
|     return CURLE_COULDNT_CONNECT;
 | |
|   }
 | |
| 
 | |
|   (void)curlx_nonblock(sock, TRUE);
 | |
| 
 | |
|   result = SOCKET_READABLE(sock, timeout);
 | |
| 
 | |
|   if(-1 == result) {
 | |
|     failf(conn->data, "SOCKS5 nothing to read");
 | |
|     return CURLE_COULDNT_CONNECT;
 | |
|   }
 | |
|   if(0 == result) {
 | |
|     failf(conn->data, "SOCKS5 read timeout");
 | |
|     return CURLE_OPERATION_TIMEDOUT;
 | |
|   }
 | |
| 
 | |
|   if(result & CURL_CSELECT_ERR) {
 | |
|     failf(conn->data, "SOCKS5 read error occurred");
 | |
|     return CURLE_RECV_ERROR;
 | |
|   }
 | |
| 
 | |
|   (void)curlx_nonblock(sock, FALSE);
 | |
| 
 | |
|   result = Curl_blockread_all(conn, sock, (char *)socksreq, 2, &actualread);
 | |
|   if(result || (actualread != 2)) {
 | |
|     failf(data, "Unable to receive initial SOCKS5 response.");
 | |
|     return CURLE_COULDNT_CONNECT;
 | |
|   }
 | |
| 
 | |
|   if(socksreq[0] != 5) {
 | |
|     failf(data, "Received invalid version in initial SOCKS5 response.");
 | |
|     return CURLE_COULDNT_CONNECT;
 | |
|   }
 | |
|   if(socksreq[1] == 0) {
 | |
|     /* Nothing to do, no authentication needed */
 | |
|     ;
 | |
|   }
 | |
| #if defined(HAVE_GSSAPI) || defined(USE_WINDOWS_SSPI)
 | |
|   else if(allow_gssapi && (socksreq[1] == 1)) {
 | |
|     code = Curl_SOCKS5_gssapi_negotiate(sockindex, conn);
 | |
|     if(code) {
 | |
|       failf(data, "Unable to negotiate SOCKS5 GSS-API context.");
 | |
|       return CURLE_COULDNT_CONNECT;
 | |
|     }
 | |
|   }
 | |
| #endif
 | |
|   else if(socksreq[1] == 2) {
 | |
|     /* Needs user name and password */
 | |
|     size_t proxy_user_len, proxy_password_len;
 | |
|     if(proxy_user && proxy_password) {
 | |
|       proxy_user_len = strlen(proxy_user);
 | |
|       proxy_password_len = strlen(proxy_password);
 | |
|     }
 | |
|     else {
 | |
|       proxy_user_len = 0;
 | |
|       proxy_password_len = 0;
 | |
|     }
 | |
| 
 | |
|     /*   username/password request looks like
 | |
|      * +----+------+----------+------+----------+
 | |
|      * |VER | ULEN |  UNAME   | PLEN |  PASSWD  |
 | |
|      * +----+------+----------+------+----------+
 | |
|      * | 1  |  1   | 1 to 255 |  1   | 1 to 255 |
 | |
|      * +----+------+----------+------+----------+
 | |
|      */
 | |
|     len = 0;
 | |
|     socksreq[len++] = 1;    /* username/pw subnegotiation version */
 | |
|     socksreq[len++] = (unsigned char) proxy_user_len;
 | |
|     if(proxy_user && proxy_user_len) {
 | |
|       /* the length must fit in a single byte */
 | |
|       if(proxy_user_len >= 255) {
 | |
|         failf(data, "Excessive user name length for proxy auth");
 | |
|         return CURLE_BAD_FUNCTION_ARGUMENT;
 | |
|       }
 | |
|       memcpy(socksreq + len, proxy_user, proxy_user_len);
 | |
|     }
 | |
|     len += proxy_user_len;
 | |
|     socksreq[len++] = (unsigned char) proxy_password_len;
 | |
|     if(proxy_password && proxy_password_len) {
 | |
|       /* the length must fit in a single byte */
 | |
|       if(proxy_password_len > 255) {
 | |
|         failf(data, "Excessive password length for proxy auth");
 | |
|         return CURLE_BAD_FUNCTION_ARGUMENT;
 | |
|       }
 | |
|       memcpy(socksreq + len, proxy_password, proxy_password_len);
 | |
|     }
 | |
|     len += proxy_password_len;
 | |
| 
 | |
|     code = Curl_write_plain(conn, sock, (char *)socksreq, len, &written);
 | |
|     if(code || (len != written)) {
 | |
|       failf(data, "Failed to send SOCKS5 sub-negotiation request.");
 | |
|       return CURLE_COULDNT_CONNECT;
 | |
|     }
 | |
| 
 | |
|     result = Curl_blockread_all(conn, sock, (char *)socksreq, 2, &actualread);
 | |
|     if(result || (actualread != 2)) {
 | |
|       failf(data, "Unable to receive SOCKS5 sub-negotiation response.");
 | |
|       return CURLE_COULDNT_CONNECT;
 | |
|     }
 | |
| 
 | |
|     /* ignore the first (VER) byte */
 | |
|     if(socksreq[1] != 0) { /* status */
 | |
|       failf(data, "User was rejected by the SOCKS5 server (%d %d).",
 | |
|             socksreq[0], socksreq[1]);
 | |
|       return CURLE_COULDNT_CONNECT;
 | |
|     }
 | |
| 
 | |
|     /* Everything is good so far, user was authenticated! */
 | |
|   }
 | |
|   else {
 | |
|     /* error */
 | |
|     if(!allow_gssapi && (socksreq[1] == 1)) {
 | |
|       failf(data,
 | |
|             "SOCKS5 GSSAPI per-message authentication is not supported.");
 | |
|       return CURLE_COULDNT_CONNECT;
 | |
|     }
 | |
|     if(socksreq[1] == 255) {
 | |
|       if(!proxy_user || !*proxy_user) {
 | |
|         failf(data,
 | |
|               "No authentication method was acceptable. (It is quite likely"
 | |
|               " that the SOCKS5 server wanted a username/password, since none"
 | |
|               " was supplied to the server on this connection.)");
 | |
|       }
 | |
|       else {
 | |
|         failf(data, "No authentication method was acceptable.");
 | |
|       }
 | |
|       return CURLE_COULDNT_CONNECT;
 | |
|     }
 | |
|     else {
 | |
|       failf(data,
 | |
|             "Undocumented SOCKS5 mode attempted to be used by server.");
 | |
|       return CURLE_COULDNT_CONNECT;
 | |
|     }
 | |
|   }
 | |
| 
 | |
|   /* Authentication is complete, now specify destination to the proxy */
 | |
|   len = 0;
 | |
|   socksreq[len++] = 5; /* version (SOCKS5) */
 | |
|   socksreq[len++] = 1; /* connect */
 | |
|   socksreq[len++] = 0; /* must be zero */
 | |
| 
 | |
|   if(!socks5_resolve_local) {
 | |
|     socksreq[len++] = 3; /* ATYP: domain name = 3 */
 | |
|     socksreq[len++] = (char) hostname_len; /* address length */
 | |
|     memcpy(&socksreq[len], hostname, hostname_len); /* address str w/o NULL */
 | |
|     len += hostname_len;
 | |
|   }
 | |
|   else {
 | |
|     struct Curl_dns_entry *dns;
 | |
|     Curl_addrinfo *hp = NULL;
 | |
|     int rc = Curl_resolv(conn, hostname, remote_port, FALSE, &dns);
 | |
| 
 | |
|     if(rc == CURLRESOLV_ERROR)
 | |
|       return CURLE_COULDNT_RESOLVE_HOST;
 | |
| 
 | |
|     if(rc == CURLRESOLV_PENDING) {
 | |
|       /* this requires that we're in "wait for resolve" state */
 | |
|       code = Curl_resolver_wait_resolv(conn, &dns);
 | |
|       if(code)
 | |
|         return code;
 | |
|     }
 | |
| 
 | |
|     /*
 | |
|      * We cannot use 'hostent' as a struct that Curl_resolv() returns.  It
 | |
|      * returns a Curl_addrinfo pointer that may not always look the same.
 | |
|      */
 | |
|     if(dns)
 | |
|       hp = dns->addr;
 | |
|     if(hp) {
 | |
|       char buf[64];
 | |
|       Curl_printable_address(hp, buf, sizeof(buf));
 | |
| 
 | |
|       if(hp->ai_family == AF_INET) {
 | |
|         int i;
 | |
|         struct sockaddr_in *saddr_in;
 | |
|         socksreq[len++] = 1; /* ATYP: IPv4 = 1 */
 | |
| 
 | |
|         saddr_in = (struct sockaddr_in *)(void *)hp->ai_addr;
 | |
|         for(i = 0; i < 4; i++) {
 | |
|           socksreq[len++] = ((unsigned char *)&saddr_in->sin_addr.s_addr)[i];
 | |
|         }
 | |
| 
 | |
|         infof(data, "SOCKS5 connect to IPv4 %s (locally resolved)\n", buf);
 | |
|       }
 | |
| #ifdef ENABLE_IPV6
 | |
|       else if(hp->ai_family == AF_INET6) {
 | |
|         int i;
 | |
|         struct sockaddr_in6 *saddr_in6;
 | |
|         socksreq[len++] = 4; /* ATYP: IPv6 = 4 */
 | |
| 
 | |
|         saddr_in6 = (struct sockaddr_in6 *)(void *)hp->ai_addr;
 | |
|         for(i = 0; i < 16; i++) {
 | |
|           socksreq[len++] =
 | |
|             ((unsigned char *)&saddr_in6->sin6_addr.s6_addr)[i];
 | |
|         }
 | |
| 
 | |
|         infof(data, "SOCKS5 connect to IPv6 %s (locally resolved)\n", buf);
 | |
|       }
 | |
| #endif
 | |
|       else {
 | |
|         hp = NULL; /* fail! */
 | |
| 
 | |
|         failf(data, "SOCKS5 connection to %s not supported\n", buf);
 | |
|       }
 | |
| 
 | |
|       Curl_resolv_unlock(data, dns); /* not used anymore from now on */
 | |
|     }
 | |
|     if(!hp) {
 | |
|       failf(data, "Failed to resolve \"%s\" for SOCKS5 connect.",
 | |
|             hostname);
 | |
|       return CURLE_COULDNT_RESOLVE_HOST;
 | |
|     }
 | |
|   }
 | |
| 
 | |
|   socksreq[len++] = (unsigned char)((remote_port >> 8) & 0xff); /* PORT MSB */
 | |
|   socksreq[len++] = (unsigned char)(remote_port & 0xff);        /* PORT LSB */
 | |
| 
 | |
| #if defined(HAVE_GSSAPI) || defined(USE_WINDOWS_SSPI)
 | |
|   if(conn->socks5_gssapi_enctype) {
 | |
|     failf(data, "SOCKS5 GSS-API protection not yet implemented.");
 | |
|   }
 | |
|   else
 | |
| #endif
 | |
|     code = Curl_write_plain(conn, sock, (char *)socksreq, len, &written);
 | |
| 
 | |
|   if(code || (len != written)) {
 | |
|     failf(data, "Failed to send SOCKS5 connect request.");
 | |
|     return CURLE_COULDNT_CONNECT;
 | |
|   }
 | |
| 
 | |
|   len = 10; /* minimum packet size is 10 */
 | |
| 
 | |
| #if defined(HAVE_GSSAPI) || defined(USE_WINDOWS_SSPI)
 | |
|   if(conn->socks5_gssapi_enctype) {
 | |
|     failf(data, "SOCKS5 GSS-API protection not yet implemented.");
 | |
|   }
 | |
|   else
 | |
| #endif
 | |
|     result = Curl_blockread_all(conn, sock, (char *)socksreq,
 | |
|                                 len, &actualread);
 | |
| 
 | |
|   if(result || (len != actualread)) {
 | |
|     failf(data, "Failed to receive SOCKS5 connect request ack.");
 | |
|     return CURLE_COULDNT_CONNECT;
 | |
|   }
 | |
| 
 | |
|   if(socksreq[0] != 5) { /* version */
 | |
|     failf(data,
 | |
|           "SOCKS5 reply has wrong version, version should be 5.");
 | |
|     return CURLE_COULDNT_CONNECT;
 | |
|   }
 | |
| 
 | |
|   /* Fix: in general, returned BND.ADDR is variable length parameter by RFC
 | |
|      1928, so the reply packet should be read until the end to avoid errors at
 | |
|      subsequent protocol level.
 | |
| 
 | |
|     +----+-----+-------+------+----------+----------+
 | |
|     |VER | REP |  RSV  | ATYP | BND.ADDR | BND.PORT |
 | |
|     +----+-----+-------+------+----------+----------+
 | |
|     | 1  |  1  | X'00' |  1   | Variable |    2     |
 | |
|     +----+-----+-------+------+----------+----------+
 | |
| 
 | |
|      ATYP:
 | |
|      o  IP v4 address: X'01', BND.ADDR = 4 byte
 | |
|      o  domain name:  X'03', BND.ADDR = [ 1 byte length, string ]
 | |
|      o  IP v6 address: X'04', BND.ADDR = 16 byte
 | |
|      */
 | |
| 
 | |
|   /* Calculate real packet size */
 | |
|   if(socksreq[3] == 3) {
 | |
|     /* domain name */
 | |
|     int addrlen = (int) socksreq[4];
 | |
|     len = 5 + addrlen + 2;
 | |
|   }
 | |
|   else if(socksreq[3] == 4) {
 | |
|     /* IPv6 */
 | |
|     len = 4 + 16 + 2;
 | |
|   }
 | |
| 
 | |
|   /* At this point we already read first 10 bytes */
 | |
| #if defined(HAVE_GSSAPI) || defined(USE_WINDOWS_SSPI)
 | |
|   if(!conn->socks5_gssapi_enctype) {
 | |
|     /* decrypt_gssapi_blockread already read the whole packet */
 | |
| #endif
 | |
|     if(len > 10) {
 | |
|       result = Curl_blockread_all(conn, sock, (char *)&socksreq[10],
 | |
|                                   len - 10, &actualread);
 | |
|       if(result || ((len - 10) != actualread)) {
 | |
|         failf(data, "Failed to receive SOCKS5 connect request ack.");
 | |
|         return CURLE_COULDNT_CONNECT;
 | |
|       }
 | |
|     }
 | |
| #if defined(HAVE_GSSAPI) || defined(USE_WINDOWS_SSPI)
 | |
|   }
 | |
| #endif
 | |
| 
 | |
|   if(socksreq[1] != 0) { /* Anything besides 0 is an error */
 | |
|     if(socksreq[3] == 1) {
 | |
|       failf(data,
 | |
|             "Can't complete SOCKS5 connection to %d.%d.%d.%d:%d. (%d)",
 | |
|             (unsigned char)socksreq[4], (unsigned char)socksreq[5],
 | |
|             (unsigned char)socksreq[6], (unsigned char)socksreq[7],
 | |
|             (((unsigned char)socksreq[8] << 8) |
 | |
|              (unsigned char)socksreq[9]),
 | |
|             (unsigned char)socksreq[1]);
 | |
|     }
 | |
|     else if(socksreq[3] == 3) {
 | |
|       unsigned char port_upper = (unsigned char)socksreq[len - 2];
 | |
|       socksreq[len - 2] = 0;
 | |
|       failf(data,
 | |
|             "Can't complete SOCKS5 connection to %s:%d. (%d)",
 | |
|             (char *)&socksreq[5],
 | |
|             ((port_upper << 8) |
 | |
|              (unsigned char)socksreq[len - 1]),
 | |
|             (unsigned char)socksreq[1]);
 | |
|       socksreq[len - 2] = port_upper;
 | |
|     }
 | |
|     else if(socksreq[3] == 4) {
 | |
|       failf(data,
 | |
|             "Can't complete SOCKS5 connection to %02x%02x:%02x%02x:"
 | |
|             "%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x:%d. (%d)",
 | |
|             (unsigned char)socksreq[4], (unsigned char)socksreq[5],
 | |
|             (unsigned char)socksreq[6], (unsigned char)socksreq[7],
 | |
|             (unsigned char)socksreq[8], (unsigned char)socksreq[9],
 | |
|             (unsigned char)socksreq[10], (unsigned char)socksreq[11],
 | |
|             (unsigned char)socksreq[12], (unsigned char)socksreq[13],
 | |
|             (unsigned char)socksreq[14], (unsigned char)socksreq[15],
 | |
|             (unsigned char)socksreq[16], (unsigned char)socksreq[17],
 | |
|             (unsigned char)socksreq[18], (unsigned char)socksreq[19],
 | |
|             (((unsigned char)socksreq[20] << 8) |
 | |
|              (unsigned char)socksreq[21]),
 | |
|             (unsigned char)socksreq[1]);
 | |
|     }
 | |
|     return CURLE_COULDNT_CONNECT;
 | |
|   }
 | |
|   infof(data, "SOCKS5 request granted.\n");
 | |
| 
 | |
|   (void)curlx_nonblock(sock, TRUE);
 | |
|   return CURLE_OK; /* Proxy was successful! */
 | |
| }
 | |
| 
 | |
| #endif /* CURL_DISABLE_PROXY */
 |