-const char gateway_rcs[] = "$Id: gateway.c,v 1.6 2001/09/10 10:41:16 oes Exp $";
/*********************************************************************
*
* File : $Source: /cvsroot/ijbswa/current/gateway.c,v $
*
* Purpose : Contains functions to connect to a server, possibly
* using a "forwarder" (i.e. HTTP proxy and/or a SOCKS4
- * proxy).
+ * or SOCKS5 proxy).
*
- * Copyright : Written by and Copyright (C) 2001 the SourceForge
- * IJBSWA team. http://ijbswa.sourceforge.net
+ * Copyright : Written by and Copyright (C) 2001-2017 the
+ * Privoxy team. http://www.privoxy.org/
*
* Based on the Internet Junkbuster originally written
- * by and Copyright (C) 1997 Anonymous Coders and
+ * by and Copyright (C) 1997 Anonymous Coders and
* Junkbusters Corporation. http://www.junkbusters.com
*
- * This program is free software; you can redistribute it
+ * This program is free software; you can redistribute it
* and/or modify it under the terms of the GNU General
* Public License as published by the Free Software
* Foundation; either version 2 of the License, or (at
* or write to the Free Software Foundation, Inc., 59
* Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
- * Revisions :
- * $Log: gateway.c,v $
- * Revision 1.6 2001/09/10 10:41:16 oes
- * Added #include in.h
- *
- * Revision 1.5 2001/07/29 18:47:57 jongfoster
- * Adding missing #include project.h
- *
- * Revision 1.4 2001/07/24 12:47:06 oes
- * Applied BeOS support update by Eugenia
- *
- * Revision 1.3 2001/06/09 10:55:28 jongfoster
- * Changing BUFSIZ ==> BUFFER_SIZE
- *
- * Revision 1.2 2001/06/07 23:11:38 jongfoster
- * Removing gateways[] list - no longer used.
- * Replacing function pointer in struct gateway with a directly
- * called function forwarded_connect(), which can do the common
- * task of deciding whether to connect to the web server or HTTP
- * proxy.
- * Replacing struct gateway with struct forward_spec
- * Fixing bug with SOCKS4A and HTTP proxy server in combination.
- * It was a bug which led to the connection being made to the web
- * server rather than the HTTP proxy, and also a buffer overrun.
- *
- * Revision 1.1.1.1 2001/05/15 13:58:54 oes
- * Initial import of version 2.9.3 source tree
- *
- *
*********************************************************************/
-\f
+
#include "config.h"
#include <stdio.h>
#include <sys/types.h>
+
+#ifndef _WIN32
#include <netinet/in.h>
+#endif
+
#include <errno.h>
#include <string.h>
+#include "assert.h"
#ifdef _WIN32
#include <winsock2.h>
#include <netdb.h>
#endif /* def __BEOS__ */
+#ifdef __OS2__
+#include <utils.h>
+#endif /* def __OS2__ */
+
#include "project.h"
#include "jcc.h"
#include "errlog.h"
#include "jbsockets.h"
#include "gateway.h"
+#include "miscutil.h"
+#include "list.h"
+#include "parsers.h"
+
+#ifdef FEATURE_CONNECTION_KEEP_ALIVE
+#ifdef HAVE_POLL
+#ifdef __GLIBC__
+#include <sys/poll.h>
+#else
+#include <poll.h>
+#endif /* def __GLIBC__ */
+#endif /* HAVE_POLL */
+#endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
-const char gateway_h_rcs[] = GATEWAY_H_VERSION;
+static jb_socket socks4_connect(const struct forward_spec * fwd,
+ const char * target_host,
+ int target_port,
+ struct client_state *csp);
-static int socks4_connect(const struct forward_spec * fwd,
- const char * target_host,
- int target_port,
- struct client_state *csp);
+static jb_socket socks5_connect(const struct forward_spec *fwd,
+ const char *target_host,
+ int target_port,
+ struct client_state *csp);
+enum {
+ SOCKS4_REQUEST_GRANTED = 90,
+ SOCKS4_REQUEST_REJECT = 91,
+ SOCKS4_REQUEST_IDENT_FAILED = 92,
+ SOCKS4_REQUEST_IDENT_CONFLICT = 93
+};
-#define SOCKS_REQUEST_GRANTED 90
-#define SOCKS_REQUEST_REJECT 91
-#define SOCKS_REQUEST_IDENT_FAILED 92
-#define SOCKS_REQUEST_IDENT_CONFLICT 93
+enum {
+ SOCKS5_REQUEST_GRANTED = 0,
+ SOCKS5_REQUEST_FAILED = 1,
+ SOCKS5_REQUEST_DENIED = 2,
+ SOCKS5_REQUEST_NETWORK_UNREACHABLE = 3,
+ SOCKS5_REQUEST_HOST_UNREACHABLE = 4,
+ SOCKS5_REQUEST_CONNECTION_REFUSED = 5,
+ SOCKS5_REQUEST_TTL_EXPIRED = 6,
+ SOCKS5_REQUEST_PROTOCOL_ERROR = 7,
+ SOCKS5_REQUEST_BAD_ADDRESS_TYPE = 8
+};
/* structure of a socks client operation */
struct socks_op {
unsigned char cd; /* command code */
unsigned char dstport[2]; /* destination port */
unsigned char dstip[4]; /* destination address */
- unsigned char userid; /* first byte of userid */
+ char userid; /* first byte of userid */
+ char padding[3]; /* make sure sizeof(struct socks_op) is endian-independent. */
/* more bytes of the userid follow, terminated by a NULL */
};
static const char socks_userid[] = "anonymous";
+#ifdef FEATURE_CONNECTION_SHARING
+
+#define MAX_REUSABLE_CONNECTIONS 100
+
+static struct reusable_connection reusable_connection[MAX_REUSABLE_CONNECTIONS];
+static int mark_connection_unused(const struct reusable_connection *connection);
+
+/*********************************************************************
+ *
+ * Function : initialize_reusable_connections
+ *
+ * Description : Initializes the reusable_connection structures.
+ * Must be called with connection_reuse_mutex locked.
+ *
+ * Parameters : N/A
+ *
+ * Returns : void
+ *
+ *********************************************************************/
+extern void initialize_reusable_connections(void)
+{
+ unsigned int slot = 0;
+
+#if !defined(HAVE_POLL) && !defined(_WIN32)
+ log_error(LOG_LEVEL_INFO,
+ "Detecting already dead connections might not work "
+ "correctly on your platform. In case of problems, "
+ "unset the keep-alive-timeout option.");
+#endif
+
+ for (slot = 0; slot < SZ(reusable_connection); slot++)
+ {
+ mark_connection_closed(&reusable_connection[slot]);
+ }
+
+ log_error(LOG_LEVEL_CONNECT, "Initialized %d socket slots.", slot);
+}
+
+
+/*********************************************************************
+ *
+ * Function : remember_connection
+ *
+ * Description : Remembers a server connection for reuse later on.
+ *
+ * Parameters :
+ * 1 : connection = The server connection to remember.
+ *
+ * Returns : void
+ *
+ *********************************************************************/
+void remember_connection(const struct reusable_connection *connection)
+{
+ unsigned int slot = 0;
+ int free_slot_found = FALSE;
+
+ assert(NULL != connection);
+ assert(connection->sfd != JB_INVALID_SOCKET);
+
+ if (mark_connection_unused(connection))
+ {
+ return;
+ }
+
+ privoxy_mutex_lock(&connection_reuse_mutex);
+
+ /* Find free socket slot. */
+ for (slot = 0; slot < SZ(reusable_connection); slot++)
+ {
+ if (reusable_connection[slot].sfd == JB_INVALID_SOCKET)
+ {
+ assert(reusable_connection[slot].in_use == 0);
+ log_error(LOG_LEVEL_CONNECT,
+ "Remembering socket %d for %s:%d in slot %d.",
+ connection->sfd, connection->host, connection->port, slot);
+ free_slot_found = TRUE;
+ break;
+ }
+ }
+
+ if (!free_slot_found)
+ {
+ log_error(LOG_LEVEL_CONNECT,
+ "No free slots found to remember socket for %s:%d. Last slot %d.",
+ connection->host, connection->port, slot);
+ privoxy_mutex_unlock(&connection_reuse_mutex);
+ close_socket(connection->sfd);
+ return;
+ }
+
+ assert(NULL != connection->host);
+ reusable_connection[slot].host = strdup_or_die(connection->host);
+ reusable_connection[slot].sfd = connection->sfd;
+ reusable_connection[slot].port = connection->port;
+ reusable_connection[slot].in_use = 0;
+ reusable_connection[slot].timestamp = connection->timestamp;
+ reusable_connection[slot].request_sent = connection->request_sent;
+ reusable_connection[slot].response_received = connection->response_received;
+ reusable_connection[slot].keep_alive_timeout = connection->keep_alive_timeout;
+ reusable_connection[slot].requests_sent_total = connection->requests_sent_total;
+
+ assert(reusable_connection[slot].gateway_host == NULL);
+ assert(reusable_connection[slot].gateway_port == 0);
+ assert(reusable_connection[slot].forwarder_type == SOCKS_NONE);
+ assert(reusable_connection[slot].forward_host == NULL);
+ assert(reusable_connection[slot].forward_port == 0);
+
+ reusable_connection[slot].forwarder_type = connection->forwarder_type;
+ if (NULL != connection->gateway_host)
+ {
+ reusable_connection[slot].gateway_host = strdup_or_die(connection->gateway_host);
+ }
+ else
+ {
+ reusable_connection[slot].gateway_host = NULL;
+ }
+ reusable_connection[slot].gateway_port = connection->gateway_port;
+
+ if (NULL != connection->forward_host)
+ {
+ reusable_connection[slot].forward_host = strdup_or_die(connection->forward_host);
+ }
+ else
+ {
+ reusable_connection[slot].forward_host = NULL;
+ }
+ reusable_connection[slot].forward_port = connection->forward_port;
+
+ privoxy_mutex_unlock(&connection_reuse_mutex);
+}
+#endif /* def FEATURE_CONNECTION_SHARING */
+
+
+/*********************************************************************
+ *
+ * Function : mark_connection_closed
+ *
+ * Description : Marks a reused connection closed.
+ *
+ * Parameters :
+ * 1 : closed_connection = The connection to mark as closed.
+ *
+ * Returns : void
+ *
+ *********************************************************************/
+void mark_connection_closed(struct reusable_connection *closed_connection)
+{
+ closed_connection->in_use = FALSE;
+ closed_connection->sfd = JB_INVALID_SOCKET;
+ freez(closed_connection->host);
+ closed_connection->port = 0;
+ closed_connection->timestamp = 0;
+ closed_connection->request_sent = 0;
+ closed_connection->response_received = 0;
+ closed_connection->keep_alive_timeout = 0;
+ closed_connection->requests_sent_total = 0;
+ closed_connection->forwarder_type = SOCKS_NONE;
+ freez(closed_connection->gateway_host);
+ closed_connection->gateway_port = 0;
+ freez(closed_connection->forward_host);
+ closed_connection->forward_port = 0;
+}
+
+
+#ifdef FEATURE_CONNECTION_SHARING
+/*********************************************************************
+ *
+ * Function : forget_connection
+ *
+ * Description : Removes a previously remembered connection from
+ * the list of reusable connections.
+ *
+ * Parameters :
+ * 1 : sfd = The socket belonging to the connection in question.
+ *
+ * Returns : void
+ *
+ *********************************************************************/
+void forget_connection(jb_socket sfd)
+{
+ unsigned int slot = 0;
+
+ assert(sfd != JB_INVALID_SOCKET);
+
+ privoxy_mutex_lock(&connection_reuse_mutex);
+
+ for (slot = 0; slot < SZ(reusable_connection); slot++)
+ {
+ if (reusable_connection[slot].sfd == sfd)
+ {
+ assert(reusable_connection[slot].in_use);
+
+ log_error(LOG_LEVEL_CONNECT,
+ "Forgetting socket %d for %s:%d in slot %d.",
+ sfd, reusable_connection[slot].host,
+ reusable_connection[slot].port, slot);
+ mark_connection_closed(&reusable_connection[slot]);
+ break;
+ }
+ }
+
+ privoxy_mutex_unlock(&connection_reuse_mutex);
+
+}
+#endif /* def FEATURE_CONNECTION_SHARING */
+
+
+#ifdef FEATURE_CONNECTION_KEEP_ALIVE
+/*********************************************************************
+ *
+ * Function : connection_destination_matches
+ *
+ * Description : Determines whether a remembered connection can
+ * be reused. That is, whether the destination and
+ * the forwarding settings match.
+ *
+ * Parameters :
+ * 1 : connection = The connection to check.
+ * 2 : http = The destination for the connection.
+ * 3 : fwd = The forwarder settings.
+ *
+ * Returns : TRUE for yes, FALSE otherwise.
+ *
+ *********************************************************************/
+int connection_destination_matches(const struct reusable_connection *connection,
+ const struct http_request *http,
+ const struct forward_spec *fwd)
+{
+ if ((connection->forwarder_type != fwd->type)
+ || (connection->gateway_port != fwd->gateway_port)
+ || (connection->forward_port != fwd->forward_port)
+ || (connection->port != http->port))
+ {
+ return FALSE;
+ }
+
+ if (( (NULL != connection->gateway_host)
+ && (NULL != fwd->gateway_host)
+ && strcmpic(connection->gateway_host, fwd->gateway_host))
+ && (connection->gateway_host != fwd->gateway_host))
+ {
+ log_error(LOG_LEVEL_CONNECT,
+ "Gateway mismatch. Previous gateway: %s. Current gateway: %s",
+ connection->gateway_host, fwd->gateway_host);
+ return FALSE;
+ }
+
+ if (( (NULL != connection->forward_host)
+ && (NULL != fwd->forward_host)
+ && strcmpic(connection->forward_host, fwd->forward_host))
+ && (connection->forward_host != fwd->forward_host))
+ {
+ log_error(LOG_LEVEL_CONNECT,
+ "Forwarding proxy mismatch. Previous proxy: %s. Current proxy: %s",
+ connection->forward_host, fwd->forward_host);
+ return FALSE;
+ }
+
+ return (!strcmpic(connection->host, http->host));
+
+}
+#endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
+
+
+#ifdef FEATURE_CONNECTION_SHARING
+/*********************************************************************
+ *
+ * Function : close_unusable_connections
+ *
+ * Description : Closes remembered connections that have timed
+ * out or have been closed on the other side.
+ *
+ * Parameters : none
+ *
+ * Returns : Number of connections that are still alive.
+ *
+ *********************************************************************/
+int close_unusable_connections(void)
+{
+ unsigned int slot = 0;
+ int connections_alive = 0;
+
+ privoxy_mutex_lock(&connection_reuse_mutex);
+
+ for (slot = 0; slot < SZ(reusable_connection); slot++)
+ {
+ if (!reusable_connection[slot].in_use
+ && (JB_INVALID_SOCKET != reusable_connection[slot].sfd))
+ {
+ time_t time_open = time(NULL) - reusable_connection[slot].timestamp;
+ time_t latency = (reusable_connection[slot].response_received -
+ reusable_connection[slot].request_sent) / 2;
+
+ if (reusable_connection[slot].keep_alive_timeout < time_open + latency)
+ {
+ log_error(LOG_LEVEL_CONNECT,
+ "The connection to %s:%d in slot %d timed out. "
+ "Closing socket %d. Timeout is: %d. Assumed latency: %d.",
+ reusable_connection[slot].host,
+ reusable_connection[slot].port, slot,
+ reusable_connection[slot].sfd,
+ reusable_connection[slot].keep_alive_timeout,
+ latency);
+ close_socket(reusable_connection[slot].sfd);
+ mark_connection_closed(&reusable_connection[slot]);
+ }
+ else if (!socket_is_still_alive(reusable_connection[slot].sfd))
+ {
+ log_error(LOG_LEVEL_CONNECT,
+ "The connection to %s:%d in slot %d is no longer usable. "
+ "Closing socket %d.", reusable_connection[slot].host,
+ reusable_connection[slot].port, slot,
+ reusable_connection[slot].sfd);
+ close_socket(reusable_connection[slot].sfd);
+ mark_connection_closed(&reusable_connection[slot]);
+ }
+ else
+ {
+ connections_alive++;
+ }
+ }
+ }
+
+ privoxy_mutex_unlock(&connection_reuse_mutex);
+
+ return connections_alive;
+
+}
+
+
+/*********************************************************************
+ *
+ * Function : get_reusable_connection
+ *
+ * Description : Returns an open socket to a previously remembered
+ * open connection (if there is one).
+ *
+ * Parameters :
+ * 1 : http = The destination for the connection.
+ * 2 : fwd = The forwarder settings.
+ *
+ * Returns : JB_INVALID_SOCKET => No reusable connection found,
+ * otherwise a usable socket.
+ *
+ *********************************************************************/
+static jb_socket get_reusable_connection(const struct http_request *http,
+ const struct forward_spec *fwd)
+{
+ jb_socket sfd = JB_INVALID_SOCKET;
+ unsigned int slot = 0;
+
+ close_unusable_connections();
+
+ privoxy_mutex_lock(&connection_reuse_mutex);
+
+ for (slot = 0; slot < SZ(reusable_connection); slot++)
+ {
+ if (!reusable_connection[slot].in_use
+ && (JB_INVALID_SOCKET != reusable_connection[slot].sfd))
+ {
+ if (connection_destination_matches(&reusable_connection[slot], http, fwd))
+ {
+ reusable_connection[slot].in_use = TRUE;
+ sfd = reusable_connection[slot].sfd;
+ log_error(LOG_LEVEL_CONNECT,
+ "Found reusable socket %d for %s:%d in slot %d. Timestamp made %d "
+ "seconds ago. Timeout: %d. Latency: %d. Requests served: %d",
+ sfd, reusable_connection[slot].host, reusable_connection[slot].port,
+ slot, time(NULL) - reusable_connection[slot].timestamp,
+ reusable_connection[slot].keep_alive_timeout,
+ (int)(reusable_connection[slot].response_received -
+ reusable_connection[slot].request_sent),
+ reusable_connection[slot].requests_sent_total);
+ break;
+ }
+ }
+ }
+
+ privoxy_mutex_unlock(&connection_reuse_mutex);
+
+ return sfd;
+
+}
+
+
+/*********************************************************************
+ *
+ * Function : mark_connection_unused
+ *
+ * Description : Gives a remembered connection free for reuse.
+ *
+ * Parameters :
+ * 1 : connection = The connection in question.
+ *
+ * Returns : TRUE => Socket found and marked as unused.
+ * FALSE => Socket not found.
+ *
+ *********************************************************************/
+static int mark_connection_unused(const struct reusable_connection *connection)
+{
+ unsigned int slot = 0;
+ int socket_found = FALSE;
+
+ assert(connection->sfd != JB_INVALID_SOCKET);
+
+ privoxy_mutex_lock(&connection_reuse_mutex);
+
+ for (slot = 0; slot < SZ(reusable_connection); slot++)
+ {
+ if (reusable_connection[slot].sfd == connection->sfd)
+ {
+ assert(reusable_connection[slot].in_use);
+ socket_found = TRUE;
+ log_error(LOG_LEVEL_CONNECT,
+ "Marking open socket %d for %s:%d in slot %d as unused.",
+ connection->sfd, reusable_connection[slot].host,
+ reusable_connection[slot].port, slot);
+ reusable_connection[slot].in_use = 0;
+ reusable_connection[slot].timestamp = connection->timestamp;
+ break;
+ }
+ }
+
+ privoxy_mutex_unlock(&connection_reuse_mutex);
+
+ return socket_found;
+
+}
+#endif /* def FEATURE_CONNECTION_SHARING */
+
/*********************************************************************
*
* a HTTP proxy and/or a SOCKS proxy.
*
* Parameters :
- * 1 : gw = pointer to a gateway structure (such as gw_default)
+ * 1 : fwd = the proxies to use when connecting.
* 2 : http = the http request and apropos headers
* 3 : csp = Current client state (buffers, headers, etc...)
*
- * Returns : -1 => failure, else it is the socket file descriptor.
+ * Returns : JB_INVALID_SOCKET => failure, else it is the socket file descriptor.
*
*********************************************************************/
-int forwarded_connect(const struct forward_spec * fwd,
- struct http_request *http,
- struct client_state *csp)
+jb_socket forwarded_connect(const struct forward_spec * fwd,
+ struct http_request *http,
+ struct client_state *csp)
{
const char * dest_host;
int dest_port;
+ jb_socket sfd = JB_INVALID_SOCKET;
+
+#ifdef FEATURE_CONNECTION_SHARING
+ if ((csp->config->feature_flags & RUNTIME_FEATURE_CONNECTION_SHARING)
+ && !(csp->flags & CSP_FLAG_SERVER_SOCKET_TAINTED))
+ {
+ sfd = get_reusable_connection(http, fwd);
+ if (JB_INVALID_SOCKET != sfd)
+ {
+ return sfd;
+ }
+ }
+#endif /* def FEATURE_CONNECTION_SHARING */
/* Figure out if we need to connect to the web server or a HTTP proxy. */
if (fwd->forward_host)
switch (fwd->type)
{
case SOCKS_NONE:
- return (connect_to(dest_host, dest_port, csp));
-
+ case FORWARD_WEBSERVER:
+ sfd = connect_to(dest_host, dest_port, csp);
+ break;
case SOCKS_4:
case SOCKS_4A:
- return (socks4_connect(fwd, dest_host, dest_port, csp));
-
+ sfd = socks4_connect(fwd, dest_host, dest_port, csp);
+ break;
+ case SOCKS_5:
+ case SOCKS_5T:
+ sfd = socks5_connect(fwd, dest_host, dest_port, csp);
+ break;
default:
/* Should never get here */
- log_error(LOG_LEVEL_FATAL, "SOCKS4 impossible internal error - bad SOCKS type.");
- errno = EINVAL;
- return(-1);
+ log_error(LOG_LEVEL_FATAL,
+ "Internal error in forwarded_connect(). Bad proxy type: %d", fwd->type);
+ }
+
+ if (JB_INVALID_SOCKET != sfd)
+ {
+ log_error(LOG_LEVEL_CONNECT,
+ "Created new connection to %s:%d on socket %d.",
+ http->host, http->port, sfd);
}
+
+ return sfd;
+
}
+#ifdef FUZZ
+/*********************************************************************
+ *
+ * Function : socks_fuzz
+ *
+ * Description : Wrapper around socks[45]_connect() used for fuzzing.
+ *
+ * Parameters :
+ * 1 : csp = Current client state (buffers, headers, etc...)
+ *
+ * Returns : JB_ERR_OK or JB_ERR_PARSE
+ *
+ *********************************************************************/
+extern jb_err socks_fuzz(struct client_state *csp)
+{
+ jb_socket socket;
+ static struct forward_spec fwd;
+ char target_host[] = "fuzz.example.org";
+ int target_port = 12345;
+
+ fwd.gateway_host = strdup_or_die("fuzz.example.org");
+ fwd.gateway_port = 12345;
+
+ fwd.type = SOCKS_4A;
+ socket = socks4_connect(&fwd, target_host, target_port, csp);
+
+ if (JB_INVALID_SOCKET != socket)
+ {
+ fwd.type = SOCKS_5;
+ socket = socks5_connect(&fwd, target_host, target_port, csp);
+ }
+
+ if (JB_INVALID_SOCKET == socket)
+ {
+ log_error(LOG_LEVEL_ERROR, "%s", csp->error_message);
+ return JB_ERR_PARSE;
+ }
+
+ log_error(LOG_LEVEL_INFO, "Input looks like an acceptable socks response");
+
+ return JB_ERR_OK;
+
+}
+#endif
+
/*********************************************************************
*
* Function : socks4_connect
* descriptor for a socket which can be treated as a
* normal (non-SOCKS) socket.
*
+ * Logged error messages are saved to csp->error_message
+ * and later reused by error_response() for the CGI
+ * message. strdup allocation failures are handled there.
+ *
* Parameters :
- * 1 : gw = pointer to a gateway structure (such as gw_default)
- * 2 : http = the http request and apropos headers
- * 3 : csp = Current client state (buffers, headers, etc...)
+ * 1 : fwd = Specifies the SOCKS proxy to use.
+ * 2 : target_host = The final server to connect to.
+ * 3 : target_port = The final port to connect to.
+ * 4 : csp = Current client state (buffers, headers, etc...)
*
- * Returns : -1 => failure, else a socket file descriptor.
+ * Returns : JB_INVALID_SOCKET => failure, else a socket file descriptor.
*
*********************************************************************/
-static int socks4_connect(const struct forward_spec * fwd,
- const char * target_host,
- int target_port,
- struct client_state *csp)
+static jb_socket socks4_connect(const struct forward_spec * fwd,
+ const char * target_host,
+ int target_port,
+ struct client_state *csp)
{
- int web_server_addr;
- unsigned char cbuf[BUFFER_SIZE];
- unsigned char sbuf[BUFFER_SIZE];
- struct socks_op *c = (struct socks_op *)cbuf;
- struct socks_reply *s = (struct socks_reply *)sbuf;
- int n;
- int csiz;
- int sfd;
+ unsigned long web_server_addr;
+ char buf[BUFFER_SIZE];
+ struct socks_op *c = (struct socks_op *)buf;
+ struct socks_reply *s = (struct socks_reply *)buf;
+ size_t n;
+ size_t csiz;
+ jb_socket sfd;
int err = 0;
- char *errstr;
+ char *errstr = NULL;
if ((fwd->gateway_host == NULL) || (*fwd->gateway_host == '\0'))
{
- log_error(LOG_LEVEL_CONNECT, "socks4_connect: NULL gateway host specified");
+ /* XXX: Shouldn't the config file parser prevent this? */
+ errstr = "NULL gateway host specified.";
err = 1;
}
if (fwd->gateway_port <= 0)
{
- log_error(LOG_LEVEL_CONNECT, "socks4_connect: invalid gateway port specified");
+ errstr = "invalid gateway port specified.";
err = 1;
}
if (err)
{
+ log_error(LOG_LEVEL_CONNECT, "socks4_connect: %s", errstr);
+ csp->error_message = strdup(errstr);
errno = EINVAL;
- return(-1);
+ return(JB_INVALID_SOCKET);
}
/* build a socks request for connection to the web server */
- strcpy((char *)&(c->userid), socks_userid);
+ strlcpy(&(c->userid), socks_userid, sizeof(buf) - sizeof(struct socks_op));
- csiz = sizeof(*c) + sizeof(socks_userid) - 1;
+ csiz = sizeof(*c) + sizeof(socks_userid) - sizeof(c->userid) - sizeof(c->padding);
switch (fwd->type)
{
case SOCKS_4:
- web_server_addr = htonl(resolve_hostname_to_ip(target_host));
+ web_server_addr = resolve_hostname_to_ip(target_host);
+ if (web_server_addr == INADDR_NONE)
+ {
+ errstr = "could not resolve target host";
+ log_error(LOG_LEVEL_CONNECT, "socks4_connect: %s %s", errstr, target_host);
+ err = 1;
+ }
+ else
+ {
+ web_server_addr = htonl(web_server_addr);
+ }
break;
case SOCKS_4A:
web_server_addr = 0x00000001;
n = csiz + strlen(target_host) + 1;
- if (n > sizeof(cbuf))
+ if (n > sizeof(buf))
{
errno = EINVAL;
- return(-1);
+ errstr = "buffer cbuf too small.";
+ log_error(LOG_LEVEL_CONNECT, "socks4_connect: %s", errstr);
+ err = 1;
+ }
+ else
+ {
+ strlcpy(buf + csiz, target_host, sizeof(buf) - sizeof(struct socks_op) - csiz);
+ /*
+ * What we forward to the socks4a server should have the
+ * size of socks_op, plus the length of the userid plus
+ * its \0 byte (which we don't have to add because the
+ * first byte of the userid is counted twice as it's also
+ * part of sock_op) minus the padding bytes (which are part
+ * of the userid as well), plus the length of the target_host
+ * (which is stored csiz bytes after the beginning of the buffer),
+ * plus another \0 byte.
+ */
+ assert(n == sizeof(struct socks_op) + strlen(&(c->userid)) - sizeof(c->padding) + strlen(buf + csiz) + 1);
+ csiz = n;
}
- strcpy(((char *)cbuf) + csiz, target_host);
- csiz = n;
break;
default:
/* Should never get here */
- log_error(LOG_LEVEL_FATAL, "SOCKS4 impossible internal error - bad SOCKS type.");
- errno = EINVAL;
- return(-1);
+ log_error(LOG_LEVEL_FATAL,
+ "socks4_connect: SOCKS4 impossible internal error - bad SOCKS type.");
+ /* Not reached */
+ return(JB_INVALID_SOCKET);
+ }
+
+ if (err)
+ {
+ csp->error_message = strdup(errstr);
+ return(JB_INVALID_SOCKET);
}
c->vn = 4;
c->cd = 1;
- c->dstport[0] = (target_port >> 8 ) & 0xff;
- c->dstport[1] = (target_port ) & 0xff;
- c->dstip[0] = (web_server_addr >> 24 ) & 0xff;
- c->dstip[1] = (web_server_addr >> 16 ) & 0xff;
- c->dstip[2] = (web_server_addr >> 8 ) & 0xff;
- c->dstip[3] = (web_server_addr ) & 0xff;
+ c->dstport[0] = (unsigned char)((target_port >> 8 ) & 0xff);
+ c->dstport[1] = (unsigned char)((target_port ) & 0xff);
+ c->dstip[0] = (unsigned char)((web_server_addr >> 24) & 0xff);
+ c->dstip[1] = (unsigned char)((web_server_addr >> 16) & 0xff);
+ c->dstip[2] = (unsigned char)((web_server_addr >> 8) & 0xff);
+ c->dstip[3] = (unsigned char)((web_server_addr ) & 0xff);
+#ifdef FUZZ
+ sfd = 0;
+#else
/* pass the request to the socks server */
sfd = connect_to(fwd->gateway_host, fwd->gateway_port, csp);
- if (sfd < 0)
+ if (sfd == JB_INVALID_SOCKET)
{
- return(-1);
+ /* The error an its reason have already been logged by connect_to() */
+ return(JB_INVALID_SOCKET);
}
-
- if ((n = write_socket(sfd, (char *)c, csiz)) != csiz)
+ else if (write_socket(sfd, (char *)c, csiz))
{
- log_error(LOG_LEVEL_CONNECT, "SOCKS4 negotiation write failed...");
+ errstr = "SOCKS4 negotiation write failed.";
+ log_error(LOG_LEVEL_CONNECT, "socks4_connect: %s", errstr);
+ err = 1;
close_socket(sfd);
- return(-1);
}
-
- if ((n = read_socket(sfd, sbuf, sizeof(sbuf))) != sizeof(*s))
+ else if (!data_is_available(sfd, csp->config->socket_timeout))
+ {
+ if (socket_is_still_alive(sfd))
+ {
+ errstr = "SOCKS4 negotiation timed out";
+ }
+ else
+ {
+ errstr = "SOCKS4 negotiation got aborted by the server";
+ }
+ log_error(LOG_LEVEL_CONNECT, "socks4_connect: %s", errstr);
+ err = 1;
+ close_socket(sfd);
+ }
+ else
+#endif
+ if (read_socket(sfd, buf, sizeof(buf)) != sizeof(*s))
{
- log_error(LOG_LEVEL_CONNECT, "SOCKS4 negotiation read failed...");
+ errstr = "SOCKS4 negotiation read failed.";
+ log_error(LOG_LEVEL_CONNECT, "socks4_connect: %s", errstr);
+ err = 1;
close_socket(sfd);
- return(-1);
+ }
+
+ if (err)
+ {
+ csp->error_message = strdup(errstr);
+ return(JB_INVALID_SOCKET);
}
switch (s->cd)
{
- case SOCKS_REQUEST_GRANTED:
+ case SOCKS4_REQUEST_GRANTED:
return(sfd);
- break;
- case SOCKS_REQUEST_REJECT:
- errstr = "SOCKS request rejected or failed";
+ case SOCKS4_REQUEST_REJECT:
+ errstr = "SOCKS request rejected or failed.";
errno = EINVAL;
break;
- case SOCKS_REQUEST_IDENT_FAILED:
+ case SOCKS4_REQUEST_IDENT_FAILED:
errstr = "SOCKS request rejected because "
- "SOCKS server cannot connect to identd on the client";
+ "SOCKS server cannot connect to identd on the client.";
errno = EACCES;
break;
- case SOCKS_REQUEST_IDENT_CONFLICT:
+ case SOCKS4_REQUEST_IDENT_CONFLICT:
errstr = "SOCKS request rejected because "
"the client program and identd report "
- "different user-ids";
+ "different user-ids.";
errno = EACCES;
break;
default:
- errstr = (char *) cbuf;
errno = ENOENT;
- sprintf(errstr,
- "SOCKS request rejected for reason code %d\n", s->cd);
+ snprintf(buf, sizeof(buf),
+ "SOCKS request rejected for reason code %d.", s->cd);
+ errstr = buf;
}
- log_error(LOG_LEVEL_CONNECT, "socks4_connect: %s ...", errstr);
-
+ log_error(LOG_LEVEL_CONNECT, "socks4_connect: %s", errstr);
+ csp->error_message = strdup(errstr);
close_socket(sfd);
- return(-1);
+
+ return(JB_INVALID_SOCKET);
}
+/*********************************************************************
+ *
+ * Function : translate_socks5_error
+ *
+ * Description : Translates a SOCKS errors to a string.
+ *
+ * Parameters :
+ * 1 : socks_error = The error code to translate.
+ *
+ * Returns : The string translation.
+ *
+ *********************************************************************/
+static const char *translate_socks5_error(int socks_error)
+{
+ switch (socks_error)
+ {
+ /* XXX: these should be more descriptive */
+ case SOCKS5_REQUEST_FAILED:
+ return "SOCKS5 request failed";
+ case SOCKS5_REQUEST_DENIED:
+ return "SOCKS5 request denied";
+ case SOCKS5_REQUEST_NETWORK_UNREACHABLE:
+ return "SOCKS5 network unreachable";
+ case SOCKS5_REQUEST_HOST_UNREACHABLE:
+ return "SOCKS5 destination host unreachable";
+ case SOCKS5_REQUEST_CONNECTION_REFUSED:
+ return "SOCKS5 connection refused";
+ case SOCKS5_REQUEST_TTL_EXPIRED:
+ return "SOCKS5 TTL expired";
+ case SOCKS5_REQUEST_PROTOCOL_ERROR:
+ return "SOCKS5 client protocol error";
+ case SOCKS5_REQUEST_BAD_ADDRESS_TYPE:
+ return "SOCKS5 domain names unsupported";
+ case SOCKS5_REQUEST_GRANTED:
+ return "everything's peachy";
+ default:
+ return "SOCKS5 negotiation protocol error";
+ }
+}
+
+
+/*********************************************************************
+ *
+ * Function : socks5_connect
+ *
+ * Description : Connect to the SOCKS server, and connect through
+ * it to the specified server. This handles
+ * all the SOCKS negotiation, and returns a file
+ * descriptor for a socket which can be treated as a
+ * normal (non-SOCKS) socket.
+ *
+ * Parameters :
+ * 1 : fwd = Specifies the SOCKS proxy to use.
+ * 2 : target_host = The final server to connect to.
+ * 3 : target_port = The final port to connect to.
+ * 4 : csp = Current client state (buffers, headers, etc...)
+ *
+ * Returns : JB_INVALID_SOCKET => failure, else a socket file descriptor.
+ *
+ *********************************************************************/
+static jb_socket socks5_connect(const struct forward_spec *fwd,
+ const char *target_host,
+ int target_port,
+ struct client_state *csp)
+{
+#define SIZE_SOCKS5_REPLY_IPV4 10
+#define SIZE_SOCKS5_REPLY_IPV6 22
+#define SOCKS5_REPLY_DIFFERENCE (SIZE_SOCKS5_REPLY_IPV6 - SIZE_SOCKS5_REPLY_IPV4)
+ int err = 0;
+ char cbuf[300];
+ char sbuf[SIZE_SOCKS5_REPLY_IPV6];
+ size_t client_pos = 0;
+ int server_size = 0;
+ size_t hostlen = 0;
+ jb_socket sfd;
+ const char *errstr = NULL;
+
+ assert(fwd->gateway_host);
+ if ((fwd->gateway_host == NULL) || (*fwd->gateway_host == '\0'))
+ {
+ errstr = "NULL gateway host specified";
+ err = 1;
+ }
+
+ if (fwd->gateway_port <= 0)
+ {
+ /*
+ * XXX: currently this can't happen because in
+ * case of invalid gateway ports we use the defaults.
+ * Of course we really shouldn't do that.
+ */
+ errstr = "invalid gateway port specified";
+ err = 1;
+ }
+
+ hostlen = strlen(target_host);
+ if (hostlen > (size_t)255)
+ {
+ errstr = "target host name is longer than 255 characters";
+ err = 1;
+ }
+
+ if ((fwd->type != SOCKS_5) && (fwd->type != SOCKS_5T))
+ {
+ /* Should never get here */
+ log_error(LOG_LEVEL_FATAL,
+ "SOCKS5 impossible internal error - bad SOCKS type");
+ err = 1;
+ }
+
+ if (err)
+ {
+ errno = EINVAL;
+ assert(errstr != NULL);
+ log_error(LOG_LEVEL_CONNECT, "socks5_connect: %s", errstr);
+ csp->error_message = strdup(errstr);
+ return(JB_INVALID_SOCKET);
+ }
+
+#ifdef FUZZ
+ sfd = 0;
+ if (!err && read_socket(sfd, sbuf, 2) != 2)
+#else
+ /* pass the request to the socks server */
+ sfd = connect_to(fwd->gateway_host, fwd->gateway_port, csp);
+
+ if (sfd == JB_INVALID_SOCKET)
+ {
+ errstr = "socks5 server unreachable";
+ log_error(LOG_LEVEL_CONNECT, "socks5_connect: %s", errstr);
+ /* Free the generic error message provided by connect_to() */
+ freez(csp->error_message);
+ csp->error_message = strdup(errstr);
+ return(JB_INVALID_SOCKET);
+ }
+
+ client_pos = 0;
+ cbuf[client_pos++] = '\x05'; /* Version */
+ cbuf[client_pos++] = '\x01'; /* One authentication method supported */
+ cbuf[client_pos++] = '\x00'; /* The no authentication authentication method */
+
+ if (write_socket(sfd, cbuf, client_pos))
+ {
+ errstr = "SOCKS5 negotiation write failed";
+ csp->error_message = strdup(errstr);
+ log_error(LOG_LEVEL_CONNECT, "%s", errstr);
+ close_socket(sfd);
+ return(JB_INVALID_SOCKET);
+ }
+ if (!data_is_available(sfd, csp->config->socket_timeout))
+ {
+ if (socket_is_still_alive(sfd))
+ {
+ errstr = "SOCKS5 negotiation timed out";
+ }
+ else
+ {
+ errstr = "SOCKS5 negotiation got aborted by the server";
+ }
+ err = 1;
+ }
+
+ if (!err && read_socket(sfd, sbuf, sizeof(sbuf)) != 2)
+#endif
+ {
+ errstr = "SOCKS5 negotiation read failed";
+ err = 1;
+ }
+
+ if (!err && (sbuf[0] != '\x05'))
+ {
+ errstr = "SOCKS5 negotiation protocol version error";
+ err = 1;
+ }
+
+ if (!err && (sbuf[1] == '\xff'))
+ {
+ errstr = "SOCKS5 authentication required";
+ err = 1;
+ }
+
+ if (!err && (sbuf[1] != '\x00'))
+ {
+ errstr = "SOCKS5 negotiation protocol error";
+ err = 1;
+ }
+
+ if (err)
+ {
+ assert(errstr != NULL);
+ log_error(LOG_LEVEL_CONNECT, "socks5_connect: %s", errstr);
+ csp->error_message = strdup(errstr);
+ close_socket(sfd);
+ errno = EINVAL;
+ return(JB_INVALID_SOCKET);
+ }
+
+ client_pos = 0;
+ cbuf[client_pos++] = '\x05'; /* Version */
+ cbuf[client_pos++] = '\x01'; /* TCP connect */
+ cbuf[client_pos++] = '\x00'; /* Reserved, must be 0x00 */
+ cbuf[client_pos++] = '\x03'; /* Address is domain name */
+ cbuf[client_pos++] = (char)(hostlen & 0xffu);
+ assert(sizeof(cbuf) - client_pos > (size_t)255);
+ /* Using strncpy because we really want the nul byte padding. */
+ strncpy(cbuf + client_pos, target_host, sizeof(cbuf) - client_pos);
+ client_pos += (hostlen & 0xffu);
+ cbuf[client_pos++] = (char)((target_port >> 8) & 0xff);
+ cbuf[client_pos++] = (char)((target_port ) & 0xff);
+
+#ifndef FUZZ
+ if (write_socket(sfd, cbuf, client_pos))
+ {
+ errstr = "SOCKS5 negotiation write failed";
+ csp->error_message = strdup(errstr);
+ log_error(LOG_LEVEL_CONNECT, "%s", errstr);
+ close_socket(sfd);
+ errno = EINVAL;
+ return(JB_INVALID_SOCKET);
+ }
+
+ /*
+ * Optimistically send the HTTP request with the initial
+ * SOCKS request if the user enabled the use of Tor extensions,
+ * the CONNECT method isn't being used (in which case the client
+ * doesn't send data until it gets our 200 response) and the
+ * client request has actually been completely read already.
+ */
+ if ((fwd->type == SOCKS_5T) && (csp->http->ssl == 0)
+ && (csp->flags & CSP_FLAG_CLIENT_REQUEST_COMPLETELY_READ))
+ {
+ char *client_headers = list_to_text(csp->headers);
+ size_t header_length;
+
+ if (client_headers == NULL)
+ {
+ log_error(LOG_LEVEL_FATAL, "Out of memory rebuilding client headers");
+ }
+ list_remove_all(csp->headers);
+ header_length= strlen(client_headers);
+
+ log_error(LOG_LEVEL_CONNECT,
+ "Optimistically sending %d bytes of client headers intended for %s",
+ header_length, csp->http->hostport);
+
+ if (write_socket(sfd, client_headers, header_length))
+ {
+ log_error(LOG_LEVEL_CONNECT,
+ "optimistically writing header to: %s failed: %E", csp->http->hostport);
+ freez(client_headers);
+ return(JB_INVALID_SOCKET);
+ }
+ freez(client_headers);
+ if (csp->expected_client_content_length != 0)
+ {
+ unsigned long long buffered_request_bytes =
+ (unsigned long long)(csp->client_iob->eod - csp->client_iob->cur);
+ log_error(LOG_LEVEL_CONNECT,
+ "Optimistically sending %llu bytes of client body. Expected %llu",
+ csp->expected_client_content_length, buffered_request_bytes);
+ assert(csp->expected_client_content_length == buffered_request_bytes);
+ if (write_socket(sfd, csp->client_iob->cur, buffered_request_bytes))
+ {
+ log_error(LOG_LEVEL_CONNECT,
+ "optimistically writing %llu bytes of client body to: %s failed: %E",
+ buffered_request_bytes, csp->http->hostport);
+ return(JB_INVALID_SOCKET);
+ }
+ clear_iob(csp->client_iob);
+ }
+ }
+#endif
+
+ server_size = read_socket(sfd, sbuf, SIZE_SOCKS5_REPLY_IPV4);
+ if (server_size != SIZE_SOCKS5_REPLY_IPV4)
+ {
+ errstr = "SOCKS5 negotiation read failed";
+ }
+ else
+ {
+ if (sbuf[0] != '\x05')
+ {
+ errstr = "SOCKS5 negotiation protocol version error";
+ }
+ else if (sbuf[2] != '\x00')
+ {
+ errstr = "SOCKS5 negotiation protocol error";
+ }
+ else if (sbuf[1] != SOCKS5_REQUEST_GRANTED)
+ {
+ errstr = translate_socks5_error(sbuf[1]);
+ }
+ else
+ {
+ if (sbuf[3] == '\x04')
+ {
+ /*
+ * The address field contains an IPv6 address
+ * which means we didn't get the whole reply
+ * yet. Read and discard the rest of it to make
+ * sure it isn't treated as HTTP data later on.
+ */
+ server_size = read_socket(sfd, sbuf, SOCKS5_REPLY_DIFFERENCE);
+ if (server_size != SOCKS5_REPLY_DIFFERENCE)
+ {
+ errstr = "SOCKS5 negotiation read failed (IPv6 address)";
+ }
+ }
+ else if (sbuf[3] != '\x01')
+ {
+ errstr = "SOCKS5 reply contains unsupported address type";
+ }
+ if (errstr == NULL)
+ {
+ return(sfd);
+ }
+ }
+ }
+
+ assert(errstr != NULL);
+ csp->error_message = strdup(errstr);
+ log_error(LOG_LEVEL_CONNECT, "socks5_connect: %s", errstr);
+ close_socket(sfd);
+ errno = EINVAL;
+
+ return(JB_INVALID_SOCKET);
+
+}
/*
Local Variables: