X-Git-Url: http://www.privoxy.org/gitweb/?p=privoxy.git;a=blobdiff_plain;f=gateway.c;h=4b6fab60571b0c2d786803bf9cf7ecb8733348df;hp=2ad02c516182266c68dfb0ad91bf56ab14677032;hb=ed843f64b12b464fe56428faffb3c7740bccfe55;hpb=4cbcbd26ea11fedf1359dbaefc50b66a55723700 diff --git a/gateway.c b/gateway.c index 2ad02c51..4b6fab60 100644 --- a/gateway.c +++ b/gateway.c @@ -1,4 +1,4 @@ -const char gateway_rcs[] = "$Id: gateway.c,v 1.9 2001/10/25 03:40:48 david__schmidt Exp $"; +const char gateway_rcs[] = "$Id: gateway.c,v 1.36 2008/10/18 19:49:15 fabiankeil Exp $"; /********************************************************************* * * File : $Source: /cvsroot/ijbswa/current/gateway.c,v $ @@ -7,8 +7,8 @@ const char gateway_rcs[] = "$Id: gateway.c,v 1.9 2001/10/25 03:40:48 david__schm * using a "forwarder" (i.e. HTTP proxy and/or a SOCKS4 * proxy). * - * Copyright : Written by and Copyright (C) 2001 the SourceForge - * IJBSWA team. http://ijbswa.sourceforge.net + * Copyright : Written by and Copyright (C) 2001-2008 the SourceForge + * Privoxy team. http://www.privoxy.org/ * * Based on the Internet Junkbuster originally written * by and Copyright (C) 1997 Anonymous Coders and @@ -34,6 +34,129 @@ const char gateway_rcs[] = "$Id: gateway.c,v 1.9 2001/10/25 03:40:48 david__schm * * Revisions : * $Log: gateway.c,v $ + * Revision 1.36 2008/10/18 19:49:15 fabiankeil + * - Factor close_unusable_connections() out of + * get_reusable_connection() to make sure we really check + * all the remembered connections, not just the ones before + * the next reusable one. + * - Plug two file descriptor leaks. Internally marking + * connections as closed doesn't cut it. + * + * Revision 1.35 2008/10/17 17:12:01 fabiankeil + * In socket_is_still_usable(), use select() + * and FD_ISSET() if poll() isn't available. + * + * Revision 1.34 2008/10/17 17:07:13 fabiankeil + * Add preliminary timeout support. + * + * Revision 1.33 2008/10/16 16:34:21 fabiankeil + * Fix two gcc44 warnings. + * + * Revision 1.32 2008/10/16 16:27:22 fabiankeil + * Fix compiler warning. + * + * Revision 1.31 2008/10/16 07:31:11 fabiankeil + * - Factor socket_is_still_usable() out of get_reusable_connection(). + * - If poll() isn't available, show a warning and assume the socket + * is still usable. + * + * Revision 1.30 2008/10/13 17:31:03 fabiankeil + * If a remembered connection is no longer usable and + * has been marked closed, don't bother checking if the + * destination matches. + * + * Revision 1.29 2008/10/11 16:59:41 fabiankeil + * Add missing dots for two log messages. + * + * Revision 1.28 2008/10/09 18:21:41 fabiankeil + * Flush work-in-progress changes to keep outgoing connections + * alive where possible. Incomplete and mostly #ifdef'd out. + * + * Revision 1.27 2008/09/27 15:05:51 fabiankeil + * Return only once in forwarded_connect(). + * + * Revision 1.26 2008/08/18 17:42:06 fabiankeil + * Fix typo in macro name. + * + * Revision 1.25 2008/02/07 18:09:46 fabiankeil + * In socks5_connect: + * - make the buffers quite a bit smaller. + * - properly report "socks5 server unreachable" failures. + * - let strncpy() use the whole buffer. Using a length of 0xffu wasn't actually + * wrong, but requires too much thinking as it doesn't depend on the buffer size. + * - log a message if the socks5 server sends more data than expected. + * - add some assertions and comments. + * + * Revision 1.24 2008/02/04 14:56:29 fabiankeil + * - Fix a compiler warning. + * - Stop assuming that htonl(INADDR_NONE) equals INADDR_NONE. + * + * Revision 1.23 2008/02/04 13:11:35 fabiankeil + * Remember the cause of the SOCKS5 error for the CGI message. + * + * Revision 1.22 2008/02/03 13:46:15 fabiankeil + * Add SOCKS5 support. Patch #1862863 by Eric M. Hopper with minor changes. + * + * Revision 1.21 2007/07/28 12:30:03 fabiankeil + * Modified patch from Song Weijia (#1762559) to + * fix socks requests on big-endian platforms. + * + * Revision 1.20 2007/05/14 10:23:48 fabiankeil + * - Use strlcpy() instead of strcpy(). + * - Use the same buffer for socks requests and socks responses. + * - Fix bogus warning about web_server_addr being used uninitialized. + * + * Revision 1.19 2007/01/25 14:09:45 fabiankeil + * - Save errors in socks4_connect() to csp->error_message. + * - Silence some gcc43 warnings, hopefully the right way. + * + * Revision 1.18 2006/07/18 14:48:46 david__schmidt + * Reorganizing the repository: swapping out what was HEAD (the old 3.1 branch) + * with what was really the latest development (the v_3_0_branch branch) + * + * Revision 1.16 2002/05/12 21:36:29 jongfoster + * Correcting function comments + * + * Revision 1.15 2002/03/26 22:29:54 swa + * we have a new homepage! + * + * Revision 1.14 2002/03/24 13:25:43 swa + * name change related issues + * + * Revision 1.13 2002/03/13 00:29:59 jongfoster + * Killing warnings + * + * Revision 1.12 2002/03/09 20:03:52 jongfoster + * - Making various functions return int rather than size_t. + * (Undoing a recent change). Since size_t is unsigned on + * Windows, functions like read_socket that return -1 on + * error cannot return a size_t. + * + * THIS WAS A MAJOR BUG - it caused frequent, unpredictable + * crashes, and also frequently caused JB to jump to 100% + * CPU and stay there. (Because it thought it had just + * read ((unsigned)-1) == 4Gb of data...) + * + * - The signature of write_socket has changed, it now simply + * returns success=0/failure=nonzero. + * + * - Trying to get rid of a few warnings --with-debug on + * Windows, I've introduced a new type "jb_socket". This is + * used for the socket file descriptors. On Windows, this + * is SOCKET (a typedef for unsigned). Everywhere else, it's + * an int. The error value can't be -1 any more, so it's + * now JB_INVALID_SOCKET (which is -1 on UNIX, and in + * Windows it maps to the #define INVALID_SOCKET.) + * + * - The signature of bind_port has changed. + * + * Revision 1.11 2002/03/08 17:46:04 jongfoster + * Fixing int/size_t warnings + * + * Revision 1.10 2002/03/07 03:50:19 oes + * - Improved handling of failed DNS lookups + * - Fixed compiler warnings + * * Revision 1.9 2001/10/25 03:40:48 david__schmidt * Change in porting tactics: OS/2's EMX porting layer doesn't allow multiple * threads to call select() simultaneously. So, it's time to do a real, live, @@ -88,6 +211,7 @@ const char gateway_rcs[] = "$Id: gateway.c,v 1.9 2001/10/25 03:40:48 david__schm #include #include +#include "assert.h" #ifdef _WIN32 #include @@ -106,13 +230,28 @@ const char gateway_rcs[] = "$Id: gateway.c,v 1.9 2001/10/25 03:40:48 david__schm #include "errlog.h" #include "jbsockets.h" #include "gateway.h" +#include "miscutil.h" +#ifdef FEATURE_CONNECTION_KEEP_ALIVE +#ifdef HAVE_POLL +#ifdef __GLIBC__ +#include +#else +#include +#endif /* def __GLIBC__ */ +#endif /* HAVE_POLL */ +#endif /* def FEATURE_CONNECTION_KEEP_ALIVE */ const char gateway_h_rcs[] = GATEWAY_H_VERSION; -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); + +static jb_socket socks5_connect(const struct forward_spec *fwd, + const char *target_host, + int target_port, + struct client_state *csp); #define SOCKS_REQUEST_GRANTED 90 @@ -120,13 +259,24 @@ static int socks4_connect(const struct forward_spec * fwd, #define SOCKS_REQUEST_IDENT_FAILED 92 #define SOCKS_REQUEST_IDENT_CONFLICT 93 +#define SOCKS5_REQUEST_GRANTED 0 +#define SOCKS5_REQUEST_FAILED 1 +#define SOCKS5_REQUEST_DENIED 2 +#define SOCKS5_REQUEST_NETWORK_UNREACHABLE 3 +#define SOCKS5_REQUEST_HOST_UNREACHABLE 4 +#define SOCKS5_REQUEST_CONNECTION_REFUSED 5 +#define SOCKS5_REQUEST_TTL_EXPIRED 6 +#define SOCKS5_REQUEST_PROTOCOL_ERROR 7 +#define SOCKS5_REQUEST_BAD_ADDRESS_TYPE 8 + /* structure of a socks client operation */ struct socks_op { unsigned char vn; /* socks version number */ 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 */ }; @@ -140,6 +290,533 @@ struct socks_reply { static const char socks_userid[] = "anonymous"; +#ifdef FEATURE_CONNECTION_KEEP_ALIVE + +#define MAX_REUSABLE_CONNECTIONS 100 +/* XXX: should be a config option. */ +#define CONNECTION_KEEP_ALIVE_TIMEOUT 3 * 60 + +struct reusable_connection +{ + jb_socket sfd; + int in_use; + char *host; + int port; + time_t timestamp; + + int forwarder_type; + char *gateway_host; + int gateway_port; + char *forward_host; + int forward_port; +}; + +static struct reusable_connection reusable_connection[MAX_REUSABLE_CONNECTIONS]; + +static int mark_connection_unused(jb_socket sfd); +static void mark_connection_closed(struct reusable_connection *closed_connection); +static int socket_is_still_usable(jb_socket sfd); + + +/********************************************************************* + * + * 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; + + log_error(LOG_LEVEL_INFO, + "Support for 'Connection: keep-alive' is experimental, " + "incomplete and known not to work properly in some situations."); + + 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 connection for reuse later on. + * + * Parameters : + * 1 : sfd = Open socket to remember. + * 2 : http = The destination for the connection. + * 3 : fwd = The forwarder settings used. + * + * Returns : void + * + *********************************************************************/ +void remember_connection(jb_socket sfd, const struct http_request *http, + const struct forward_spec *fwd) +{ + unsigned int slot = 0; + int free_slot_found = FALSE; + + assert(sfd != JB_INVALID_SOCKET); + + if (mark_connection_unused(sfd)) + { + 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.", + sfd, http->host, http->port, slot); + free_slot_found = TRUE; + break; + } + } + + if (!free_slot_found) + { + log_error(LOG_LEVEL_CONNECT, + "No free slots found to remembering socket for %s:%d. Last slot %d.", + http->host, http->port, slot); + privoxy_mutex_unlock(&connection_reuse_mutex); + close_socket(sfd); + return; + } + + assert(NULL != http->host); + reusable_connection[slot].host = strdup(http->host); + if (NULL == reusable_connection[slot].host) + { + log_error(LOG_LEVEL_FATAL, "Out of memory saving socket."); + } + reusable_connection[slot].sfd = sfd; + reusable_connection[slot].port = http->port; + reusable_connection[slot].in_use = 0; + reusable_connection[slot].timestamp = time(NULL); + + assert(NULL != fwd); + 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 = fwd->type; + if (NULL != fwd->gateway_host) + { + reusable_connection[slot].gateway_host = strdup(fwd->gateway_host); + if (NULL == reusable_connection[slot].gateway_host) + { + log_error(LOG_LEVEL_FATAL, "Out of memory saving gateway_host."); + } + } + else + { + reusable_connection[slot].gateway_host = NULL; + } + reusable_connection[slot].gateway_port = fwd->gateway_port; + + if (NULL != fwd->forward_host) + { + reusable_connection[slot].forward_host = strdup(fwd->forward_host); + if (NULL == reusable_connection[slot].forward_host) + { + log_error(LOG_LEVEL_FATAL, "Out of memory saving forward_host."); + } + } + else + { + reusable_connection[slot].forward_host = NULL; + } + reusable_connection[slot].forward_port = fwd->forward_port; + + privoxy_mutex_unlock(&connection_reuse_mutex); +} + + +/********************************************************************* + * + * Function : mark_connection_closed + * + * Description : Marks a reused connection closed. + * Must be called with connection_reuse_mutex locked. + * + * Parameters : + * 1 : closed_connection = The connection to mark as closed. + * + * Returns : void + * + *********************************************************************/ +static 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->forwarder_type = SOCKS_NONE; + freez(closed_connection->gateway_host); + closed_connection->gateway_port = 0; + freez(closed_connection->forward_host); + closed_connection->forward_port = 0; +} + + +/********************************************************************* + * + * 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]); + privoxy_mutex_unlock(&connection_reuse_mutex); + + return; + } + } + + log_error(LOG_LEVEL_CONNECT, + "Socket %d already forgotten or never remembered.", sfd); + + privoxy_mutex_unlock(&connection_reuse_mutex); +} + + +/********************************************************************* + * + * 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. + * + *********************************************************************/ +static int connection_destination_matches(const struct reusable_connection *connection, + const struct http_request *http, + const struct forward_spec *fwd) +{ + /* XXX: Start of duplicated checks for debugging purposes. */ + if (strcmpic(connection->host, http->host)) + { + return FALSE; + } + + if (connection->forwarder_type != fwd->type) + { + log_error(LOG_LEVEL_CONNECT, "Type mismatch: %d %d (%s)", + connection->forwarder_type, fwd->type, http->host); + return FALSE; + } + if (connection->gateway_port != fwd->gateway_port) + { + log_error(LOG_LEVEL_CONNECT, "Gateway port mismatch: %d %d (%s)", + connection->gateway_port, fwd->gateway_port, http->host); + return FALSE; + } + if (connection->forward_port != fwd->forward_port) + { + log_error(LOG_LEVEL_CONNECT, "Forward port mismatch: %d %d (%s)", + connection->forward_port, fwd->forward_port, http->host); + return FALSE; + } + if (connection->forward_port != fwd->forward_port) + { + log_error(LOG_LEVEL_CONNECT, "Server port mismatch: %d %d (%s)", + connection->forward_port, fwd->forward_port, http->host); + return FALSE; + } + + /* XXX: End of duplicated checks for debugging purposes. */ + + 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."); + 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."); + return FALSE; + } + + return (!strcmpic(connection->host, http->host)); + +} + + +/********************************************************************* + * + * Function : close_unusable_connections + * + * Description : Closes remembered connections that have timed + * out or have been closed on the other side. + * + * Parameters : none + * + * Returns : void + * + *********************************************************************/ +static void close_unusable_connections(void) +{ + unsigned int slot = 0; + + 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; + + if (CONNECTION_KEEP_ALIVE_TIMEOUT < time_open) + { + log_error(LOG_LEVEL_CONNECT, + "The connection to %s:%d in slot %d timed out. Closing.", + reusable_connection[slot].host, reusable_connection[slot].port, + slot); + close_socket(reusable_connection[slot].sfd); + mark_connection_closed(&reusable_connection[slot]); + continue; + } + + if (!socket_is_still_usable(reusable_connection[slot].sfd)) + { + log_error(LOG_LEVEL_CONNECT, + "Socket %d for %s:%d in slot %d is no longer usable. Closing.", + reusable_connection[slot].sfd, reusable_connection[slot].host, + reusable_connection[slot].port, slot); + close_socket(reusable_connection[slot].sfd); + mark_connection_closed(&reusable_connection[slot]); + continue; + } + } + } +} + + +/********************************************************************* + * + * Function : socket_is_still_usable + * + * Description : Decides whether or not an open socket is still usable. + * + * Parameters : + * 1 : sfd = The socket to check. + * + * Returns : TRUE for yes, otherwise FALSE. + * + *********************************************************************/ +static int socket_is_still_usable(jb_socket sfd) +{ +#ifdef HAVE_POLL + int poll_result; + struct pollfd poll_fd[1]; + + memset(poll_fd, 0, sizeof(poll_fd)); + poll_fd[0].fd = sfd; + poll_fd[0].events = POLLIN; + + poll_result = poll(poll_fd, 1, 0); + + if (-1 != poll_result) + { + return !(poll_fd[0].revents & POLLIN); + } + else + { + log_error(LOG_LEVEL_CONNECT, "Polling socket %d failed.", sfd); + return FALSE; + } +#else + fd_set readable_fds; + struct timeval timeout; + int ret; + int socket_is_alive = 0; + + memset(&timeout, '\0', sizeof(timeout)); + /* timeout.tv_usec = 150;*/ + FD_ZERO(&readable_fds); + FD_SET(sfd, &readable_fds); + + ret = select((int)sfd+1, &readable_fds, NULL, NULL, &timeout); + if (ret < 0) + { + log_error(LOG_LEVEL_ERROR, "select() failed!: %E"); + } + + /* + * XXX: I'm not sure why !FD_ISSET() works, + * but apparently it does. + */ + socket_is_alive = !FD_ISSET(sfd, &readable_fds); + + log_error(LOG_LEVEL_INFO, + "Detecting already dead sockets might not work correctly " + "on your platform. Anyway, socket %d appears to be %s.", + sfd, (socket_is_alive ? "still alive" : "already dead")); + + return socket_is_alive; +#endif /* def HAVE_POLL */ +} + + +/********************************************************************* + * + * 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; + + privoxy_mutex_lock(&connection_reuse_mutex); + + close_unusable_connections(); + + 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.", + sfd, reusable_connection[slot].host, reusable_connection[slot].port, slot); + break; + } + } + } + + privoxy_mutex_unlock(&connection_reuse_mutex); + + return sfd; + +} + + +/********************************************************************* + * + * Function : mark_connection_unused + * + * Description : Gives a remembered connection free for reuse. + * + * Parameters : + * 1 : sfd = The socket belonging to the connection in question. + * + * Returns : TRUE => Socket found and marked as unused. + * FALSE => Socket not found. + * + *********************************************************************/ +static int mark_connection_unused(jb_socket sfd) +{ + unsigned int slot = 0; + int socket_found = FALSE; + + 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); + socket_found = TRUE; + log_error(LOG_LEVEL_CONNECT, + "Marking open socket %d for %s:%d in slot %d as unused.", + sfd, reusable_connection[slot].host, + reusable_connection[slot].port, slot); + reusable_connection[slot].in_use = 0; + reusable_connection[slot].timestamp = time(NULL); + break; + } + } + + privoxy_mutex_unlock(&connection_reuse_mutex); + + return socket_found; + +} +#endif /* def FEATURE_CONNECTION_KEEP_ALIVE */ + /********************************************************************* * @@ -149,19 +826,34 @@ static const char socks_userid[] = "anonymous"; * 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_KEEP_ALIVE + sfd = get_reusable_connection(http, fwd); + if (JB_INVALID_SOCKET == sfd) + { + log_error(LOG_LEVEL_CONNECT, + "No reusable socket for %s:%d found. Opening a new one.", + http->host, http->port); + } + else + { + return sfd; + } +#endif /* def FEATURE_CONNECTION_KEEP_ALIVE */ /* Figure out if we need to connect to the web server or a HTTP proxy. */ if (fwd->forward_host) @@ -181,18 +873,23 @@ int forwarded_connect(const struct forward_spec * fwd, switch (fwd->type) { case SOCKS_NONE: - return (connect_to(dest_host, dest_port, csp)); - + 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: + 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, + "SOCKS4 impossible internal error - bad SOCKS type."); } + + return sfd; + } @@ -206,111 +903,157 @@ int forwarded_connect(const struct forward_spec * fwd, * 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; - char cbuf[BUFFER_SIZE]; - char sbuf[BUFFER_SIZE]; - struct socks_op *c = (struct socks_op *)cbuf; - struct socks_reply *s = (struct socks_reply *)sbuf; - int n; + unsigned int 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; - int sfd; + 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) { - log_error(LOG_LEVEL_CONNECT, "socks4_connect: could not resolve target host %s", target_host); - return(-1); + 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(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); /* 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); + /* + * XXX: connect_to should fill in the exact reason. + * Most likely resolving the IP of the forwarder failed. + */ + errstr = "connect_to failed: see logfile for details"; + err = 1; } - - 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 (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) @@ -319,34 +1062,277 @@ static int socks4_connect(const struct forward_spec * fwd, return(sfd); break; case SOCKS_REQUEST_REJECT: - errstr = "SOCKS request rejected or failed"; + errstr = "SOCKS request rejected or failed."; errno = EINVAL; break; case SOCKS_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: errstr = "SOCKS request rejected because " "the client program and identd report " - "different user-ids"; + "different user-ids."; errno = EACCES; break; default: - errstr = 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 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) +{ + int err = 0; + char cbuf[300]; + char sbuf[30]; + 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 > 255) + { + errstr = "target host name is longer than 255 characters"; + err = 1; + } + + if (fwd->type != SOCKS_5) + { + /* 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); + } + + /* 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); + 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 (read_socket(sfd, sbuf, sizeof(sbuf)) != 2) + { + 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 > 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); + + if (write_socket(sfd, cbuf, client_pos)) + { + errstr = "SOCKS5 negotiation read failed"; + csp->error_message = strdup(errstr); + log_error(LOG_LEVEL_CONNECT, "%s", errstr); + close_socket(sfd); + errno = EINVAL; + return(JB_INVALID_SOCKET); + } + + server_size = read_socket(sfd, sbuf, sizeof(sbuf)); + if (server_size < 3) + { + errstr = "SOCKS5 negotiation read failed"; + err = 1; + } + else if (server_size > 20) + { + /* This is somewhat unexpected but doesn't realy matter. */ + log_error(LOG_LEVEL_CONNECT, "socks5_connect: read %d bytes " + "from socks server. Would have accepted up to %d.", + server_size, sizeof(sbuf)); + } + + if (!err && (sbuf[0] != '\x05')) + { + errstr = "SOCKS5 negotiation protocol version error"; + err = 1; + } + + if (!err && (sbuf[2] != '\x00')) + { + errstr = "SOCKS5 negotiation protocol error"; + err = 1; + } + + if (!err) + { + if (sbuf[1] == SOCKS5_REQUEST_GRANTED) + { + return(sfd); + } + errstr = translate_socks5_error(sbuf[1]); + err = 1; + } + + 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: