From: ankry Date: Wed, 27 Aug 2003 10:40:21 +0000 (+0000) Subject: c78de727e1208799072be78c05d64398 connect.c X-Git-Tag: RA-DEVEL X-Git-Url: http://git.pld-linux.org/?p=packages%2Fconnect.git;a=commitdiff_plain;h=refs%2Ftags%2Fauto%2Fac%2Fopenssh-3_8p1-0_2 c78de727e1208799072be78c05d64398 connect.c Changed files: connect.c -> 1.1 --- diff --git a/connect.c b/connect.c new file mode 100644 index 0000000..6a74031 --- /dev/null +++ b/connect.c @@ -0,0 +1,2545 @@ +/*********************************************************************** + * connect.c -- Make socket connection using SOCKS4/5 and HTTP tunnel. + * + * Copyright (c) 2000, 2001 Shun-ichi Goto + * Copyright (c) 2002, J. Grant (English Corrections) + * + * 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 your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + * + * --------------------------------------------------------- + * PROJECT: My Test Program + * AUTHOR: Shun-ichi GOTO + * CREATE: Wed Jun 21, 2000 + * REVISION: $Revision$ + * --------------------------------------------------------- + * + * Getting Source + * ============== + * + * Recent version of 'connect.c' is available from + * http://www.imasy.or.jp/~gotoh/ssh/connect.c + * + * Pre-compiled biniary for Win32 is also available: + * http://www.imasy.or.jp/~gotoh/ssh/connect.exe.gz + * + * Related tool, ssh-askpass.exe (alternative ssh-askpass on UNIX) + * is available: + * http://www.imasy.or.jp/~gotoh/ssh/ssh-askpass.exe.gz + * + * How To Compile + * ============== + * + * On UNIX environment: + * $ gcc connect.c -o connect + * + * On SOLARIS: + * $ gcc -o connect -lresolv -lsocket -lnsl connect.c + * + * on Win32 environment: + * $ cl connect.c wsock32.lib advapi32.lib + * or + * $ bcc32 connect.c wsock32.lib advapi32.lib + * or + * $ gcc connect.c -o connect + * + * How To Use + * ========== + * + * You can specify proxy method in an environment variable or in a + * command line option. + * + * usage: connect [-dnhs45] [-R resolve] [-p local-port] [-w sec] + * [-H [user@]proxy-server[:port]] + * [-S [user@]socks-server[:port]] + * host port + * + * "host" and "port" is for the target hostname and port-number to + * connect to. + * + * The -H option specifys a hostname and port number of the http proxy + * server to relay. If port is omitted, 80 is used. You can specify this + * value in the environment variable HTTP_PROXY and pass the -h option + * to use it. + * + * The -S option specifys the hostname and port number of the SOCKS + * server to relay. Like -H, port number can be omitted and the default + * is 1080. You can also specify this value pair in the environment + * variable SOCKS5_SERVER and give the -s option to use it. + * + * The '-4' and the '-5' options are for specifying SOCKS relaying and + * indicates protocol version to use. It is valid only when used with + * '-s' or '-S'. Default is '-5' (protocol version 5) + * + * The '-R' option is for specifying method to resolve the + * hostname. Three keywords ("local", "remote", "both") or dot-notation + * IP address are acceptable. The keyword "both" means, "Try local + * first, then remote". If a dot-notation IP address is specified, use + * this host as nameserver. The default is "remote" for SOCKS5 or + * "local" for others. On SOCKS4 protocol, remote resolving method + * ("remote" and "both") requires protocol 4a supported server. + * + * The '**-p**' option will forward a local TCP port instead of using the + * standard input and output. + * + * The '-w' option specifys timeout seconds for making connection with + * TARGET host. + * + * The '-d' option is used for debug. If you fail to connect, use this + * and check request to and response from server. + * + * You can omit the "port" argument when program name is special format + * containing port number itself. For example, + * $ ln -s connect connect-25 + * means this connect-25 command is spcifying port number 25 already + * so you need not 2nd argument (and ignored if specified). + * + * To use proxy, this example is for SOCKS5 connection to connect to + * 'host' at port 25 via SOCKS5 server on 'firewall' host. + * $ connect -S firewall host 25 + * or + * $ SOCKS5_SERVER=firewall; export SOCKS5_SERVER + * $ connect -s host 25 + * + * For a HTTP-PROXY connection: + * $ connect -H proxy-server:8080 host 25 + * or + * $ HTTP_PROXY=proxy-server:8080; export HTTP_PROXY + * $ connect -h host 25 + * To forward a local port, for example to use ssh: + * $ connect -p 5550 -H proxy-server:8080 host 22 + * ($ ssh -l user -p 5550 localhost ) + * + * TIPS + * ==== + * + * Connect.c doesn't have any configuration to specify the SOCKS server. + * If you are a mobile user, this limitation might bother you. However, + * You can compile connect.c and link with other standard SOCKS library + * like the NEC SOCKS5 library or Dante. This means connect.c is + * socksified and uses a configration file like to other SOCKSified + * network commands and you can switch configuration file any time + * (ex. when ppp startup) that brings you switching of SOCKS server for + * connect.c in same way with other commands. For this case, you can + * write ~/.ssh/config like this: + * + * ProxyCommand connect -n %h %p + * + * SOCKS5 authentication + * ===================== + * + * Only USER/PASS authentication is supported. + * + * Proxy authentication + * ==================== + * + * Only BASIC scheme is supported. + * + * Authentication informations + * =========================== + * + * User name for authentication is specifed by an environment variable + * or system login name. And Password is specified from environment + * variable or external program (specified in $SSH_ASKPASS) or tty. + * + * Following environment variable is used for specifying user name. + * SOCKS: $SOCKS5_USER, $LOGNAME, $USER + * HTTP Proxy: $HTTP_PROXY_USER, $LOGNAME, $USER + * + * ssh-askpass support + * =================== + * + * You can use ssh-askpass (came from OpenSSH or else) to specify + * password on graphical environment (X-Window or MS Windows). To use + * this, set program name to environment variable SSH_ASKPASS. On UNIX, + * X-Window must be required, so $DISPLAY environment variable is also + * needed. On Win32 environment, $DISPLAY is not mentioned. + * + * Related Informations + * ==================== + * + * SOCKS5 -- RFC 1928, RFC 1929, RFC 1961 + * NEC SOCKS Reference Implementation is available from: + * http://www.socks.nec.com + * DeleGate version 5 or earlier can be SOCKS4 server, + * and version 6 can be SOCKS5 and SOCKS4 server. + * and version 7.7.0 or later can be SOCKS5 and SOCKS4a server. + * http://www.delegate.org/delegate/ + * + * HTTP-Proxy -- + * Many http proxy servers supports this, but https should + * be allowed as configuration on your host. + * For example on DeleGate, you should add "https" to the + * "REMITTABLE" parameter to allow HTTP-Proxy like this: + * delegated -Pxxxx ...... REMITTABLE="+,https" ... + * + * Hypertext Transfer Protocol -- HTTP/1.1 -- RFC 2616 + * HTTP Authentication: Basic and Digest Access Authentication -- RFC 2617 + * For proxy authentication, refer these documents. + * + ***********************************************************************/ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#ifdef __CYGWIN32__ +#undef _WIN32 +#endif + +#ifdef _WIN32 +#include +#include +#include +#include +#include +#else /* !_WIN32 */ +#include +#include +#include +#include +#ifndef __hpux +#include +#endif /* __hpux */ +#include +#include +#include +#include +#ifndef __CYGWIN32__ +#include +#include +#endif /* !__CYGWIN32__ */ +#endif /* !_WIN32 */ + +#ifdef _WIN32 +#define ECONNRESET WSAECONNRESET +#endif /* _WI32 */ + + + +#ifndef LINT +static char *vcid = "$Id$"; +#endif + + +/* consider Borland C */ +#ifdef __BORLANDC__ +#define _kbhit kbhit +#endif + +/* help message. + Win32 environment does not support -R option. + Win32 native compilers does not support -w option, yet. +*/ +static char *usage = +#ifdef _WIN32 +"usage: %s [-dnhs45] \n" +#else /* not _WIN32 */ +#ifdef __CYGWIN32__ +/* help message for UNIX */ +"usage: %s [-dnhs45] [-R resolve] [-w timeout] \n" +#else /* not __CYGWIN32__ */ +"usage: %s [-dnhs45] [-R resolve] [-w timeout] \n" +#endif /* __CYGWIN32__ */ +#endif /* not _WIN32 */ +" [-H proxy-server[:port]] [-S [user@]socks-server[:port]] \n" +" host port\n"; + +/* name of this program */ +char *progname = NULL; +char *progdesc = "connect --- simple relaying command via proxy."; +char *rcs_revstr = "$Revision$"; +char *revstr = NULL; + +/* options */ +int f_debug = 0; + +/* report flag to hide secure information */ +int f_report = 1; + +int connect_timeout = 0; + +/* local input type */ +#define LOCAL_STDIO 0 +#define LOCAL_SOCKET 1 +char *local_type_names[] = { "stdio", "socket" }; +int local_type = LOCAL_STDIO; +u_short local_port = 0; + +/* utiity types, pair holder of number and string */ +typedef struct { + int num; + const char *str; +} LOOKUP_ITEM; + +/* relay method, server and port */ +#define METHOD_UNDECIDED 0 +#define METHOD_DIRECT 1 +#define METHOD_SOCKS 2 +#define METHOD_HTTP 3 +char *method_names[] = { "UNDECIDED", "DIRECT", "SOCKS", "HTTP" }; + +int relay_method = METHOD_UNDECIDED; /* relaying method */ +char *relay_host = NULL; /* hostname of relay server */ +u_short relay_port = 0; /* port of relay server */ +char *relay_user = NULL; /* user name for auth */ + +/* destination target host and port */ +char *dest_host = NULL; +struct sockaddr_in dest_addr; +u_short dest_port = 0; + +/* informations for SOCKS */ +#define SOCKS5_REP_SUCCEEDED 0x00 /* succeeded */ +#define SOCKS5_REP_FAIL 0x01 /* general SOCKS serer failure */ +#define SOCKS5_REP_NALLOWED 0x02 /* connection not allowed by ruleset */ +#define SOCKS5_REP_NUNREACH 0x03 /* Network unreachable */ +#define SOCKS5_REP_HUNREACH 0x04 /* Host unreachable */ +#define SOCKS5_REP_REFUSED 0x05 /* connection refused */ +#define SOCKS5_REP_EXPIRED 0x06 /* TTL expired */ +#define SOCKS5_REP_CNOTSUP 0x07 /* Command not supported */ +#define SOCKS5_REP_ANOTSUP 0x08 /* Address not supported */ +#define SOCKS5_REP_INVADDR 0x09 /* Inalid address */ + +LOOKUP_ITEM socks5_rep_names[] = { + { SOCKS5_REP_SUCCEEDED, "succeeded"}, + { SOCKS5_REP_FAIL, "general SOCKS server failure"}, + { SOCKS5_REP_NALLOWED, "connection not allowed by ruleset"}, + { SOCKS5_REP_NUNREACH, "Network unreachable"}, + { SOCKS5_REP_HUNREACH, "Host unreachable"}, + { SOCKS5_REP_REFUSED, "connection refused"}, + { SOCKS5_REP_EXPIRED, "TTL expired"}, + { SOCKS5_REP_CNOTSUP, "Command not supported"}, + { SOCKS5_REP_ANOTSUP, "Address not supported"}, + { SOCKS5_REP_INVADDR, "Invalid address"}, + { -1, NULL } +}; + +/* SOCKS5 authentication methods */ +#define SOCKS5_AUTH_REJECT 0xFF /* No acceptable auth method */ +#define SOCKS5_AUTH_NOAUTH 0x00 /* without authentication */ +#define SOCKS5_AUTH_GSSAPI 0x01 /* GSSAPI */ +#define SOCKS5_AUTH_USERPASS 0x02 /* User/Password */ +#define SOCKS5_AUTH_CHAP 0x03 /* Challenge-Handshake Auth Proto. */ +#define SOCKS5_AUTH_EAP 0x05 /* Extensible Authentication Proto. */ +#define SOCKS5_AUTH_MAF 0x08 /* Multi-Authentication Framework */ + +#define SOCKS4_REP_SUCCEEDED 90 /* rquest granted (succeeded) */ +#define SOCKS4_REP_REJECTED 91 /* request rejected or failed */ +#define SOCKS4_REP_IDENT_FAIL 92 /* cannot connect identd */ +#define SOCKS4_REP_USERID 93 /* user id not matched */ + +LOOKUP_ITEM socks4_rep_names[] = { + { SOCKS4_REP_SUCCEEDED, "request granted (succeeded)"}, + { SOCKS4_REP_REJECTED, "request rejected or failed"}, + { SOCKS4_REP_IDENT_FAIL, "cannot connect identd"}, + { SOCKS4_REP_USERID, "user id not matched"}, + { -1, NULL } +}; + +#define RESOLVE_UNKNOWN 0 +#define RESOLVE_LOCAL 1 +#define RESOLVE_REMOTE 2 +#define RESOLVE_BOTH 3 +char *resolve_names[] = { "UNKNOWN", "LOCAL", "REMOTE", "BOTH" }; + +int socks_version = 5; /* SOCKS protocol version */ +int socks_resolve = RESOLVE_UNKNOWN; +struct sockaddr_in socks_ns; +char *socks5_auth = NULL; + +/* Environment variable names */ +#define ENV_SOCKS_SERVER "SOCKS_SERVER" /* SOCKS server */ +#define ENV_SOCKS5_SERVER "SOCKS5_SERVER" +#define ENV_SOCKS4_SERVER "SOCKS4_SERVER" + +#define ENV_SOCKS_RESOLVE "SOCKS_RESOLVE" /* resolve method */ +#define ENV_SOCKS5_RESOLVE "SOCKS5_RESOLVE" +#define ENV_SOCKS4_RESOLVE "SOCKS4_RESOLVE" + +#define ENV_SOCKS5_USER "SOCKS5_USER" /* auth user for SOCKS5 */ +#define ENV_SOCKS5_PASSWORD "SOCKS5_PASSWORD" /* auth password for SOCKS5 */ + +#define ENV_HTTP_PROXY "HTTP_PROXY" /* common env var */ +#define ENV_HTTP_PROXY_USER "HTTP_PROXY_USER" /* auth user */ +#define ENV_HTTP_PROXY_PASSWORD "HTTP_PROXY_PASSWORD" /* auth password */ + +#define ENV_CONNECT_USER "CONNECT_USER" /* default auth user name */ +#define ENV_CONNECT_PASSWORD "CONNECT_PASSWORD" /* default auth password */ + +#define ENV_SOCKS_DIRECT "SOCKS_DIRECT" /* addr-list for non-proxy */ +#define ENV_SOCKS5_DIRECT "SOCKS5_DIRECT" +#define ENV_SOCKS4_DIRECT "SOCKS4_DIRECT" +#define ENV_HTTP_DIRECT "HTTP_DIRECT" +#define ENV_CONNECT_DIRECT "CONNECT_DIRECT" + +#define ENV_SOCKS5_AUTH "SOCKS5_AUTH" +#define ENV_SSH_ASKPASS "SSH_ASKPASS" /* askpass program */ + +/* Prefix string of HTTP_PROXY */ +#define HTTP_PROXY_PREFIX "http://" +#define PROXY_AUTH_NONE 0 +#define PROXY_AUTH_BASIC 1 +#define PROXY_AUTH_DIGEST 2 +int proxy_auth_type = PROXY_AUTH_NONE; + + +/* return value of relay start function. */ +#define START_ERROR -1 +#define START_OK 0 +#define START_RETRY 1 + +/* socket related definitions */ +#ifndef _WIN32 +#define SOCKET int +#endif +#ifndef SOCKET_ERROR +#define SOCKET_ERROR -1 +#endif + +#ifndef FD_ALLOC +#define FD_ALLOC(nfds) ((fd_set*)malloc((nfds+7)/8)) +#endif /* !FD_ALLOC */ + +#ifdef _WIN32 +#define socket_errno() WSAGetLastError() +#else /* !_WIN32 */ +#define closesocket close +#define socket_errno() (errno) +#endif /* !_WIN32 */ + +#ifdef _WIN32 +#define popen _popen +#endif /* WIN32 */ + +/* packet operation macro */ +#define PUT_BYTE(ptr,data) (*(unsigned char*)ptr = data) + +/* debug message output */ +void +debug( const char *fmt, ... ) +{ + va_list args; + if ( f_debug ) { + va_start( args, fmt ); + fprintf(stderr, "DEBUG: "); + vfprintf( stderr, fmt, args ); + va_end( args ); + } +} + +void +debug_( const char *fmt, ... ) /* without prefix */ +{ + va_list args; + if ( f_debug ) { + va_start( args, fmt ); + vfprintf( stderr, fmt, args ); + va_end( args ); + } +} + +/* error message output */ +void +error( const char *fmt, ... ) +{ + va_list args; + va_start( args, fmt ); + fprintf(stderr, "ERROR: "); + vfprintf( stderr, fmt, args ); + va_end( args ); +} + +void +fatal( const char *fmt, ... ) +{ + va_list args; + va_start( args, fmt ); + fprintf(stderr, "FATAL: "); + vfprintf( stderr, fmt, args ); + va_end( args ); + exit (EXIT_FAILURE); +} + +void +downcase( char *buf ) +{ + while ( *buf ) { + if ( isupper(*buf) ) + *buf += 'a'-'A'; + buf++; + } +} + +int +lookup_resolve( const char *str ) +{ + char *buf = strdup( str ); + int ret; + + downcase( buf ); + if ( strcmp( buf, "both" ) == 0 ) + ret = RESOLVE_BOTH; + else if ( strcmp( buf, "remote" ) == 0 ) + ret = RESOLVE_REMOTE; + else if ( strcmp( buf, "local" ) == 0 ) + ret = RESOLVE_LOCAL; + else if ( strspn(buf, "0123456789.") == strlen(buf) ) { +#if defined(_WIN32) || defined(__CYGWIN32__) + fatal("Sorry, you can't specify to resolve the hostname with the -R option on Win32 environment."); +#endif /* _WIN32 || __CYGWIN32__ */ + ret = RESOLVE_LOCAL; /* this case is also 'local' */ + socks_ns.sin_addr.s_addr = inet_addr(buf); + socks_ns.sin_family = AF_INET; + } + else + ret = RESOLVE_UNKNOWN; + free(buf); + return ret; +} + +char * +getusername(void) +{ +#ifdef _WIN32 + static char buf[1024]; + DWORD size = sizeof(buf); + buf[0] = '\0'; + GetUserName( buf, &size); + return buf; +#else /* not _WIN32 */ + struct passwd *pw = getpwuid(getuid()); + if ( pw == NULL ) + fatal("getpwuid() failed for uid: %d\n", getuid()); + return pw->pw_name; +#endif /* not _WIN32 */ +} + +/* expect + check STR is begin with substr with case-ignored comparison. + Return 1 if matched, otherwise 0. +*/ +int +expect( char *str, char *substr) +{ + int len = strlen(substr); + while ( 0 < len-- ) { + if ( toupper(*str) != toupper(*substr) ) + return 0; /* not matched */ + str++, substr++; + } + return 1; /* good, matched */ +} + + +/** PARAMETER operation **/ +#define PARAMETER_FILE "/etc/connectrc" +#define PARAMETER_DOTFILE ".connectrc" +typedef struct { + char* name; + char* value; +} PARAMETER_ITEM; +PARAMETER_ITEM parameter_table[] = { + { ENV_SOCKS_SERVER, NULL }, + { ENV_SOCKS5_SERVER, NULL }, + { ENV_SOCKS4_SERVER, NULL }, + { ENV_SOCKS_RESOLVE, NULL }, + { ENV_SOCKS5_RESOLVE, NULL }, + { ENV_SOCKS4_RESOLVE, NULL }, + { ENV_SOCKS5_USER, NULL }, + { ENV_SOCKS5_PASSWORD, NULL }, + { ENV_HTTP_PROXY, NULL }, + { ENV_HTTP_PROXY_USER, NULL }, + { ENV_HTTP_PROXY_PASSWORD, NULL }, + { ENV_CONNECT_USER, NULL }, + { ENV_CONNECT_PASSWORD, NULL }, + { ENV_SSH_ASKPASS, NULL }, + { ENV_SOCKS5_DIRECT, NULL }, + { ENV_SOCKS4_DIRECT, NULL }, + { ENV_SOCKS_DIRECT, NULL }, + { ENV_HTTP_DIRECT, NULL }, + { ENV_CONNECT_DIRECT, NULL }, + { ENV_SOCKS5_AUTH, NULL }, + { NULL, NULL } +}; + +PARAMETER_ITEM* +find_parameter_item(const char* name){ + int i; + for( i = 0; parameter_table[i].name != NULL; i++ ){ + if ( strncmp(name, parameter_table[i].name, strlen(parameter_table[i].name)) == 0 ) + return ¶meter_table[i]; + } + return NULL; +} + +void +read_parameter_file_1(const char* name){ + FILE* f; + int line; + char lbuf[1025]; + f = fopen(name, "r"); + if( f ){ + debug("Reading parameter file(%s)\n", name); + for ( line = 1; fgets(lbuf, 1024, f); line++ ) { + char *p, *q, *param = NULL, *value = NULL; + p = strchr(lbuf, '\n'); + if ( p == NULL ) + fatal("%s:%d: buffer overflow\n", name, line); + *p = '\0'; + p = strchr(lbuf, '#'); + if ( p ) + *p = '\0'; + for ( p = lbuf; *p; p++ ) + if( *p != ' ' && *p != '\t' ) break; + if ( *p == '\0' ) continue; + param = p; + p = strchr(p, '='); + if ( p == NULL ) { + error("%s:%d: missing equal sign\n", name, line); + continue; + } + for ( q = p - 1; q >= lbuf; q-- ) + if ( *q != ' ' && *q != '\t' ) break; + *++q = '\0'; + for ( ++p; *p; p++ ) + if ( *p != ' ' && *p != '\t' ) break; + value = p; + for ( ; *p; p++ ); + for ( p--; p >= lbuf; p-- ) + if ( *p != ' ' && *p != '\t' ) break; + *++p = '\0'; + if ( param && value ) { + PARAMETER_ITEM *item; + item = find_parameter_item(param); + if ( item == NULL ) { + error("%s:%d: unknown parameter `%s'\n", name, line, param); + continue; + } + item->value = strdup(value); + debug("Parameter `%s' is set to `%s'\n", param, value); + } + } + } +} + +void +read_parameter_file(void){ +#ifndef _WIN32 + char *name; + struct passwd *pw; +#endif + + read_parameter_file_1(PARAMETER_FILE); +#ifndef _WIN32 + pw = getpwuid(getuid()); + if ( pw == NULL ) + fatal("getpwuid() failed for uid: %d\n", getuid()); + name = malloc(strlen(pw->pw_dir) + strlen(PARAMETER_DOTFILE) + 2); + if ( name == NULL ) + fatal("Can't allocate memory\n"); + strcpy(name, pw->pw_dir); + strcat(name, "/" PARAMETER_DOTFILE); + read_parameter_file_1(name); + free(name); +#endif /* _WIN32 */ +} + +char* +getparam(const char* name){ + char *value = getenv(name); + if ( value == NULL ){ + PARAMETER_ITEM *item = find_parameter_item(name); + if ( item != NULL ) + value = item->value; + } + return value; +} + + +/** DIRECT connection **/ +#define MAX_DIRECT_ADDR_LIST 256 + +struct ADDRPAIR { + struct in_addr addr; + struct in_addr mask; + int negative; +}; + +struct ADDRPAIR direct_addr_list[MAX_DIRECT_ADDR_LIST]; +int n_direct_addr_list = 0; + +void +mask_addr (void *addr, void *mask, int addrlen) +{ + char *a, *m; + a = addr; + m = mask; + while ( 0 < addrlen-- ) + *a++ &= *m++; +} + +int +add_direct_addr (struct in_addr *addr, struct in_addr *mask, int negative) +{ + struct in_addr iaddr; + char *s; + if ( MAX_DIRECT_ADDR_LIST <= n_direct_addr_list ) { + error("direct address table is full!\n"); + return -1; + } + iaddr = *addr; + mask_addr(&iaddr, mask, sizeof(iaddr)); + s = strdup(inet_ntoa(iaddr)); + debug("adding direct address entry: %s/%s\n", s, inet_ntoa(*mask)); + free(s); + memcpy( &direct_addr_list[n_direct_addr_list].addr, + &iaddr, sizeof(iaddr)); + memcpy( &direct_addr_list[n_direct_addr_list].mask, + mask, sizeof(*mask)); + direct_addr_list[n_direct_addr_list].negative = negative; + n_direct_addr_list++; + return 0; +} + +int +parse_addr_pair (const char *str, struct in_addr *addr, struct in_addr *mask) +{ + /* NOTE: */ + /* Assme already be splitted by separator + and formatted as folowing: + 1) 12.34.56.789/255.255.255.0 + 2) 12.34.56.789/24 + 3) 12.34.56. + All above generates same addr/mask pair 12.34.56.0 and 255.255.255.0 + */ + const char *ptr; + u_char *dsta, *dstm; + int i, n; + + assert( str != NULL ); + debug("parsing address pair: '%s'\n", str); + addr->s_addr = 0; + mask->s_addr = 0; + ptr = str; + dsta = (u_char*)&addr->s_addr; + dstm = (u_char*)&mask->s_addr; + for (i=0; i<4; i++ ) { + if ( *ptr == '\0' ) + break; /* case of format #3 */ + if ( !isdigit(*ptr) ) + return -1; /* format error: */ + *dsta++ = atoi( ptr ); + *dstm++ = 255; /* automatic mask for format #3 */ + while ( isdigit(*ptr) ) /* skip digits */ + ptr++; + if ( *ptr == '.' ) + ptr++; + else + break; + } + /* At this point, *ptr points '/' or EOS ('\0') */ + if ( *ptr == '\0' ) + return 0; /* complete as format #3 */ + if ( *ptr != '/' ) + return -1; /* format error */ + /* Now parse mask for format #1 or #2 */ + ptr++; + mask->s_addr = 0; /* clear automatic mask */ + + if ( strchr( ptr, '.') ) { + /* case of format #1 */ + dstm = (u_char*)&mask->s_addr; + for (i=0; i<4; i++) { + if ( !isdigit(*ptr) ) + return -1; /* format error: */ + *dstm++ = atoi(ptr); + while ( isdigit(*ptr) ) /* skip digits */ + ptr++; + if ( *ptr == '.' ) + ptr++; + else + break; /* from for loop */ + } + /* complete as format #1 */ + } else { + /* case of format #2 */ + if ( !isdigit(*ptr) ) + return -1; /* format error: */ + n = atoi(ptr); + if ( n<0 || 32s_addr = (n==0)? 0: htonl(((u_long)0xFFFFFFFF)<<(32-n)); + /* complete as format #1 */ + } + return 0; +} + +void +initialize_direct_addr (void) +{ + int negative; + int n_entries; + char *env = NULL, *beg, *next, *envkey = NULL; + struct in_addr addr, mask; + + if ( relay_method == METHOD_SOCKS ){ + if ( socks_version == 5 ) + envkey = ENV_SOCKS5_DIRECT; + else + envkey = ENV_SOCKS4_DIRECT; + env = getparam(envkey); + if ( env == NULL ) + env = getparam(ENV_SOCKS_DIRECT); + } else if ( relay_method == METHOD_HTTP ){ + env = getparam(ENV_HTTP_DIRECT); + } + + if ( env == NULL ) + env = getparam(ENV_CONNECT_DIRECT); + + if ( env == NULL ) + return; /* no entry */ + debug("making direect addr list from: '%s'\n", env); + env = strdup( env ); /* reallocate to modify */ + beg = next = env; + n_entries = 0; + do { + if ( MAX_DIRECT_ADDR_LIST <= n_entries ) { + error("too many entries in %s", envkey); + break; /* from do loop */ + } + next = strchr( beg, ','); + if ( next != NULL ) + *next++ = '\0'; + addr.s_addr = 0; + mask.s_addr = 0; + if (*beg == '!') { + negative = 1; + beg++; + } else + negative = 0; + if ( !parse_addr_pair( beg, &addr, &mask ) ) { + add_direct_addr( &addr, &mask, negative ); + } else { + error("invalid addr format in %s: %s\n", envkey, beg); + } + if ( next != NULL ) + beg = next; + } while ( next != NULL ); + + free( env ); + return; +} + +int +cmp_addr (void *addr1, void *addr2, int addrlen) +{ + return memcmp( addr1, addr2, addrlen ); +} + +int +is_direct_address (const struct sockaddr_in *addr, int addrlen) +{ + int i; + struct in_addr saddr, iaddr; + + saddr = addr->sin_addr; + + /* Note: assume IPV4 address !! */ + for (i=0; is_port); + debug("service: %s => %d\n", service, port); + } + } + return (u_short)port; +} + +void +make_revstr(void) +{ + char *ptr; + size_t len; + ptr = strstr(rcs_revstr, ": "); + if (!ptr) { + revstr = strdup("unknown"); + return; + } + ptr += 2; + len = strspn(ptr, "0123456789."); + if (0 < len) { + revstr = malloc(len+1); + memcpy(revstr, ptr, len); + revstr[len] = '\0'; + } +} + +int +getarg( int argc, char **argv ) +{ + int err = 0; + char *ptr, *server = (char*)NULL; + int method = METHOD_DIRECT; + + progname = *argv; + argc--, argv++; + + /* check optinos */ + while ( (0 < argc) && (**argv == '-') ) { + ptr = *argv + 1; + while ( *ptr ) { + switch ( *ptr ) { + case 's': /* use SOCKS */ + method = METHOD_SOCKS; + break; + + case 'n': /* no proxy */ + method = METHOD_DIRECT; + break; + + case 'h': /* use http-proxy */ + method = METHOD_HTTP; + break; + + case 'S': /* specify SOCKS server */ + if ( 0 < argc ) { + argv++, argc--; + method = METHOD_SOCKS; + server = *argv; + } else { + error("option '-%c' needs argument.\n", *ptr); + err++; + } + break; + + case 'H': /* specify http-proxy server */ + if ( 0 < argc ) { + argv++, argc--; + method = METHOD_HTTP; + server = *argv; + } else { + error("option '-%c' needs argument.\n", *ptr); + err++; + } + break; + + case 'P': + /* destination port number */ + if ( 0 < argc ) { + argv++, argc--; + dest_port = resolve_port(*argv); + } else { + error("option '-%c' needs argument.\n", *ptr); + err++; + } + break; + + case 'p': /* specify port to forward */ + if ( 0 < argc ) { + argv++, argc--; + local_type = LOCAL_SOCKET; + local_port = resolve_port(*argv); + } else { + error("option '-%c' needs argument.\n", *ptr); + err++; + } + break; + +#ifndef _WIN32 + case 'w': + if ( 0 < argc ) { + argv++, argc--; + connect_timeout = atoi(*argv); + } else { + error("option '-%c' needs argument.\n", *ptr); + err++; + } + break; +#endif /* not _WIN32 */ + + case '4': + socks_version = 4; + break; + + case '5': + socks_version = 5; + break; + + case 'a': + if ( 0 < argc ) { + argv++, argc--; + socks5_auth = *argv; + } else { + error("option '-%c' needs argument.\n", *ptr); + err++; + } + break; + + case 'R': /* specify resolve method */ + if ( 0 < argc ) { + argv++, argc--; + socks_resolve = lookup_resolve( *argv ); + } else { + error("option '-%c' needs argument.\n", *ptr); + err++; + } + break; + + case 'V': /* print version */ + fprintf(stderr, "%s\nVersion %s\n", progdesc, revstr); + exit(0); + + case 'd': /* debug mode */ + f_debug = 1; + break; + + default: + error("unknown option '-%c'\n", *ptr); + err++; + } + ptr++; + } + argc--, argv++; + } + + /* check error */ + if ( 0 < err ) + goto quit; + + set_relay( method, server ); + + /* check destination HOST (MUST) */ + if ( argc == 0 ) { + fprintf(stderr, "%s\nVersion %s\n", progdesc, revstr); + fprintf(stderr, usage, progname); + exit(0); + } + dest_host = argv[0]; + /* decide port or service name from programname or argument */ + if ( ((ptr=strrchr( progname, '/' )) != NULL) || + ((ptr=strchr( progname, '\\')) != NULL) ) + ptr++; + else + ptr = progname; + if ( dest_port == 0 ) { + /* accept only if -P is not specified. */ + if ( 1 < argc ) { + /* get port number from argument (prior to progname) */ + /* NOTE: This way is for cvs ext method. */ + dest_port = resolve_port(argv[1]); + } else if ( strncmp( ptr, "connect-", 8) == 0 ) { + /* decide port number from program name */ + char *str = strdup( ptr+8 ); + str[strcspn( str, "." )] = '\0'; + dest_port = resolve_port(str); + free(str); + } + } + /* check port number */ + if ( dest_port <= 0 ) { + error( "You must specify the destination port correctly.\n"); + err++; + goto quit; + } + if ( (relay_method != METHOD_DIRECT) && (relay_port <= 0) ) { + error("Invalid relay port: %d\n", dest_port); + err++; + goto quit; + } + +quit: + /* report for debugging */ + debug("relay_method = %s (%d)\n", + method_names[relay_method], relay_method); + if ( relay_method != METHOD_DIRECT ) { + debug("relay_host=%s\n", relay_host); + debug("relay_port=%d\n", relay_port); + debug("relay_user=%s\n", relay_user); + } + if ( relay_method == METHOD_SOCKS ) { + debug("socks_version=%d\n", socks_version); + debug("socks_resolve=%s (%d)\n", + resolve_names[socks_resolve], socks_resolve); + } + debug("local_type=%s\n", local_type_names[local_type]); + if ( local_type == LOCAL_SOCKET ) + debug("local_port=%d\n", local_port); + debug("dest_host=%s\n", dest_host); + debug("dest_port=%d\n", dest_port); + if ( 0 < err ) { + fprintf(stderr, usage, progname); + exit(1); + } + return 0; +} + +#ifndef _WIN32 +/* Time-out feature is not allowed for Win32 native compilers. */ +/* MSVC and Borland C cannot but Cygwin and UNIXes can. */ + +/* timeout signal hander */ +void +sig_timeout(void) +{ + debug( "timed out\n" ); + signal( SIGALRM, SIG_IGN ); + alarm( 0 ); +} + +/* set timeout param = seconds, 0 clears */ +void +set_timeout(int timeout) +{ + /* This feature is allowed for UNIX or cygwin environments, currently */ + if ( timeout == 0 ) { + debug( "clearing timeout\n" ); + signal( SIGALRM, SIG_IGN ); + alarm( 0 ); + } else { + debug( "setting timeout: %d seconds\n", timeout ); + signal(SIGALRM, (void *)sig_timeout); + alarm( timeout ); + } +} +#endif + + +/* TODO: IPv6 */ + +int +local_resolve (const char *host, struct sockaddr_in *addr, + struct sockaddr_in *ns) +{ + struct hostent *ent; + if ( strspn(host, "0123456789.") == strlen(host) ) { + /* given by IPv4 address */ + addr->sin_family = AF_INET; + addr->sin_addr.s_addr = inet_addr(host); + } else { +#if !defined(_WIN32) && !defined(__CYGWIN32__) + if (ns != 0 && ns->sin_addr.s_addr != 0) { + res_init(); + memcpy (&_res.nsaddr_list[0], ns, sizeof(*ns)); + _res.nscount = 1; + debug("Using nameserver at %s\n", inet_ntoa(ns->sin_addr)); + } +#endif /* !_WIN32 && !__CYGWIN32__ */ + debug("resolving host by name: %s\n", host); + ent = gethostbyname (host); + if ( ent ) { + memcpy (&addr->sin_addr, ent->h_addr, ent->h_length); + addr->sin_family = ent->h_addrtype; + debug("resolved: %s (%s)\n", + host, inet_ntoa(addr->sin_addr)); + } else { + debug("failed to resolve locally.\n"); + return -1; /* failed */ + } + } + return 0; /* good */ +} + +SOCKET +open_connection( const char *host, u_short port ) +{ + SOCKET s; + struct sockaddr_in saddr; + + if ( relay_method == METHOD_DIRECT ) { + host = dest_host; + port = dest_port; + } else if ((local_resolve (dest_host, &saddr, NULL) >= 0)&& + (is_direct_address(&saddr, sizeof(saddr)))) { + debug("%s is connected directly\n", dest_host); + relay_method = METHOD_DIRECT; + host = dest_host; + port = dest_port; + } else { + host = relay_host; + port = relay_port; + } + + if (local_resolve (host, &saddr, NULL) < 0) { + error("can't resolve hostname: %s\n", host); + return SOCKET_ERROR; + } + saddr.sin_port = htons(port); + + debug("connecting to %s:%u\n", inet_ntoa(saddr.sin_addr), port); + s = socket( AF_INET, SOCK_STREAM, 0 ); + if ( connect( s, (struct sockaddr *)&saddr, sizeof(saddr)) + == SOCKET_ERROR) { + debug( "connect() failed.\n"); + return SOCKET_ERROR; + } + return s; +} + +void +report_text( char *prefix, char *buf ) +{ + static char work[1024]; + char *tmp; + + if ( !f_debug ) + return; + if ( !f_report ) + return; /* don't report */ + debug("%s \"", prefix); + while ( *buf ) { + memset( work, 0, sizeof(work)); + tmp = work; + while ( *buf && ((tmp-work) < sizeof(work)-5) ) { + switch ( *buf ) { + case '\t': *tmp++ = '\\'; *tmp++ = 't'; break; + case '\r': *tmp++ = '\\'; *tmp++ = 'r'; break; + case '\n': *tmp++ = '\\'; *tmp++ = 'n'; break; + case '\\': *tmp++ = '\\'; *tmp++ = '\\'; break; + default: + if ( isprint(*buf) ) { + *tmp++ = *buf; + } else { + sprintf( tmp, "\\x%02X", (unsigned char)*buf); + tmp += strlen(tmp); + } + } + buf++; + *tmp = '\0'; + } + debug_("%s", work); + } + + debug_("\"\n"); +} + + +void +report_bytes( char *prefix, char *buf, int len ) +{ + if ( ! f_debug ) + return; + debug( "%s", prefix ); + while ( 0 < len ) { + fprintf( stderr, " %02x", *(unsigned char *)buf); + buf++; + len--; + } + fprintf(stderr, "\n"); + return; +} + +int +atomic_out( SOCKET s, char *buf, int size ) +{ + int ret, len; + + assert( buf != NULL ); + assert( 0<=size ); + /* do atomic out */ + ret = 0; + while ( 0 < size ) { + len = send( s, buf+ret, size, 0 ); + if ( len == -1 ) + fatal("atomic_out() failed to send(), %d\n", socket_errno()); + ret += len; + size -= len; + } + if (!f_report) { + debug("atomic_out() [some bytes]\n"); + debug(">>> xx xx xx xx ...\n"); + } else { + debug("atomic_out() [%d bytes]\n", ret); + report_bytes(">>>", buf, ret); + } + return ret; +} + +int +atomic_in( SOCKET s, char *buf, int size ) +{ + int ret, len; + + assert( buf != NULL ); + assert( 0<=size ); + + /* do atomic in */ + ret = 0; + while ( 0 < size ) { + len = recv( s, buf+ret, size, 0 ); + if ( len == -1 ) { + fatal("atomic_in() failed to recv(), %d\n", socket_errno()); + } else if ( len == 0 ) { + fatal( "Connection closed by peer.\n"); + } + ret += len; + size -= len; + } + if (!f_report) { + debug("atomic_in() [some bytes]\n"); + debug("<<< xx xx xx xx ...\n"); + } else { + debug("atomic_in() [%d bytes]\n", ret); + report_bytes("<<<", buf, ret); + } + return ret; +} + +int +line_input( SOCKET s, char *buf, int size ) +{ + char *dst = buf; + if ( size == 0 ) + return 0; /* no error */ + size--; + while ( 0 < size ) { + switch ( recv( s, dst, 1, 0) ) { /* recv one-by-one */ + case SOCKET_ERROR: + error("recv() error\n"); + return -1; /* error */ + case 0: + size = 0; /* end of stream */ + break; + default: + /* continue reading until last 1 char is EOL? */ + if ( *dst == '\n' ) { + /* finished */ + size = 0; + } else { + /* more... */ + size--; + } + dst++; + } + } + *dst = '\0'; + report_text( "<<<", buf); + return 0; +} + +void +skip_all_lines (SOCKET s) +{ + char buf[1024]; + while (0 < recv (s, buf, sizeof(buf), 0)) + ; +} + +/* cut_token() + Span token in given string STR until char in DELIM is appeared. + Then replace contiguous DELIMS with '\0' for string termination + and returns next pointer. + If no next token, return NULL. +*/ +char * +cut_token( char *str, char *delim) +{ + char *ptr = str + strcspn(str, delim); + char *end = ptr + strspn(ptr, delim); + if ( ptr == str ) + return NULL; + while ( ptr < end ) + *ptr++ = '\0'; + return ptr; +} + +const char * +lookup(int num, LOOKUP_ITEM *items) +{ + int i = 0; + while (0 <= items[i].num) { + if (items[i].num == num) + return items[i].str; + i++; + } + return "(unknown)"; +} + +/* readpass() + password input routine + Use ssh-askpass (same mechanism to OpenSSH) +*/ +char * +readpass( const char* prompt, ...) +{ + static char buf[1000]; /* XXX, don't be fix length */ + va_list args; + va_start(args, prompt); + vsprintf(buf, prompt, args); + va_end(args); + + if ( getparam(ENV_SSH_ASKPASS) +#if !defined(_WIN32) && !defined(__CYGWIN32__) + && getenv("DISPLAY") +#endif /* not _WIN32 && not __CYGWIN32__ */ + ) { + /* use ssh-askpass to get password */ + FILE *fp; + char *askpass = getparam(ENV_SSH_ASKPASS), *cmd; + cmd = malloc(strlen(askpass) +1 +1 +strlen(buf) +1); + sprintf(cmd, "%s \"%s\"", askpass, buf); + fp = popen(cmd, "r"); + free(cmd); + if ( fp == NULL ) + return NULL; /* fail */ + buf[0] = '\0'; + if (fgets(buf, sizeof(buf), fp) == NULL) + return NULL; /* fail */ + fclose(fp); + } else { + tty_readpass( buf, buf, sizeof(buf)); + } + buf[strcspn(buf, "\r\n")] = '\0'; + return buf; +} + +static int +socks5_do_auth_userpass( int s ) +{ + unsigned char buf[1024], *ptr; + char *pass; + int len; + + /* do User/Password authentication. */ + /* This feature requires username and password from + command line argument or environment variable, + or terminal. */ + if ( relay_user == NULL ) + fatal("User name cannot be decided.\n"); + + /* get password from environment variable if exists. */ + if ((pass=getparam(ENV_SOCKS5_PASSWORD)) == NULL && + (pass=readpass("Enter SOCKS5 password for %s@%s: ", + relay_user, relay_host)) == NULL ) + fatal("Cannot get password for user: %s\n", relay_user); + + /* make authentication packet */ + ptr = buf; + PUT_BYTE( ptr++, 1 ); /* subnegotiation ver.: 1 */ + len = strlen( relay_user ); /* ULEN and UNAME */ + PUT_BYTE( ptr++, len ); + strcpy( ptr, relay_user ); + ptr += len; + len = strlen( pass ); /* PLEN and PASSWD */ + PUT_BYTE( ptr++, strlen(pass)); + strcpy( ptr, pass ); + ptr += len; + + /* send it and get answer */ + f_report = 0; + atomic_out( s, buf, ptr-buf ); + f_report = 1; + atomic_in( s, buf, 2 ); + + /* check status */ + if ( buf[1] == 0 ) + return 0; /* success */ + else + return -1; /* fail */ +} + +static const char * +socks5_getauthname( int auth ) +{ + switch ( auth ) { + case SOCKS5_AUTH_REJECT: return "REJECTED"; + case SOCKS5_AUTH_NOAUTH: return "NO-AUTH"; + case SOCKS5_AUTH_GSSAPI: return "GSSAPI"; + case SOCKS5_AUTH_USERPASS: return "USERPASS"; + case SOCKS5_AUTH_CHAP: return "CHAP"; + case SOCKS5_AUTH_EAP: return "EAP"; + case SOCKS5_AUTH_MAF: return "MAF"; + default: return "(unknown)"; + } +} + +typedef struct { + char* name; + unsigned char auth; +} AUTH_METHOD_ITEM; + +AUTH_METHOD_ITEM socks5_auth_table[] = { + { "none", SOCKS5_AUTH_NOAUTH }, + { "gssapi", SOCKS5_AUTH_GSSAPI }, + { "userpass", SOCKS5_AUTH_USERPASS }, + { "chap", SOCKS5_AUTH_CHAP }, + { NULL, -1 }, +}; + +int +socks5_auth_parse_1(char *start, char *end){ + int i, len; + for ( ; *start; start++ ) + if ( *start != ' ' && *start != '\t') break; + for ( end--; end >= start; end-- ) { + if ( *end != ' ' && *end != '\t'){ + end++; + break; + } + } + len = end - start; + for ( i = 0; socks5_auth_table[i].name != NULL; i++ ){ + if ( strncmp(start, socks5_auth_table[i].name, len) == 0) { + return socks5_auth_table[i].auth; + } + } + fatal("Unknown auth method: %s\n", start); + return -1; +} + +int +socks5_auth_parse(char *start, unsigned char *auth_list, int max_auth){ + char *end; + int i = 0; + while ( i < max_auth ) { + if ( *start && ( end = strchr(start, ',') ) ){ + auth_list[i++] = socks5_auth_parse_1(start, end); + start = ++end; + } else { + break; + } + } + if ( *start && ( i < max_auth ) ){ + for( end = start; *end; end++ ); + auth_list[i++] = socks5_auth_parse_1(start, end); + } else { + fatal("Too much auth method.\n"); + } + return i; +} + +/* begin SOCKS5 relaying + And no authentication is supported. + */ +int +begin_socks5_relay( SOCKET s ) +{ + unsigned char buf[256], *ptr, *env = socks5_auth; + unsigned char n_auth = 0; unsigned char auth_list[10], auth_method; + int len, auth_result, i; + + debug( "begin_socks_relay()\n"); + + /* request authentication */ + ptr = buf; + PUT_BYTE( ptr++, 5); /* SOCKS version (5) */ + + if ( env == NULL ) + env = getparam(ENV_SOCKS5_AUTH); + if ( env == NULL ) { + /* add no-auth authentication */ + auth_list[n_auth++] = SOCKS5_AUTH_NOAUTH; + /* add user/pass authentication */ + auth_list[n_auth++] = SOCKS5_AUTH_USERPASS; + } else { + n_auth = socks5_auth_parse(env, auth_list, 10); + } + PUT_BYTE( ptr++, n_auth); /* num auth */ + for (i=0; i>8); /* DST.PORT */ + PUT_BYTE( ptr++, dest_port&0xFF); + atomic_out( s, buf, ptr-buf); /* send request */ + atomic_in( s, buf, 4 ); /* recv response */ + if ( (buf[1] != SOCKS5_REP_SUCCEEDED) ) { /* check reply code */ + error("Got error response from SOCKS server: %d (%s).\n", + buf[1], lookup(buf[1], socks5_rep_names)); + return -1; + } + ptr = buf + 4; + switch ( buf[3] ) { /* case by ATYP */ + case 1: /* IP v4 ADDR*/ + atomic_in( s, ptr, 4+2 ); /* recv IPv4 addr and port */ + break; + case 3: /* DOMAINNAME */ + atomic_in( s, ptr, 1 ); /* recv name and port */ + atomic_in( s, ptr+1, *(unsigned char*)ptr + 2); + break; + case 4: /* IP v6 ADDR */ + atomic_in( s, ptr, 16+2 ); /* recv IPv6 addr and port */ + break; + } + + /* Conguraturation, connected via SOCKS5 server! */ + return 0; +} + +/* begin SOCKS protocol 4 relaying + And no authentication is supported. + + There's SOCKS protocol version 4 and 4a. Protocol version + 4a has capability to resolve hostname by SOCKS server, so + we don't need resolving IP address of destination host on + local machine. + + Environment variable SOCKS_RESOLVE directs how to resolve + IP addess. There's 3 keywords allowed; "local", "remote" + and "both" (case insensitive). Keyword "local" means taht + target host name is resolved by localhost resolver + (usualy with gethostbyname()), "remote" means by remote + SOCKS server, "both" means to try resolving by localhost + then remote. + + SOCKS4 protocol and authentication of SOCKS5 protocol + requires user name on connect request. + User name is determined by following method. + + 1. If server spec has user@hostname:port format then + user part is used for this SOCKS server. + + 2. Get user name from environment variable LOGNAME, USER + (in this order). + +*/ +int +begin_socks4_relay( SOCKET s ) +{ + unsigned char buf[256], *ptr; + + debug( "begin_socks_relay()\n"); + + /* make connect request packet + protocol v4: + VN:1, CD:1, PORT:2, ADDR:4, USER:n, NULL:1 + protocol v4a: + VN:1, CD:1, PORT:2, DUMMY:4, USER:n, NULL:1, HOSTNAME:n, NULL:1 + */ + ptr = buf; + PUT_BYTE( ptr++, 4); /* protocol version (4) */ + PUT_BYTE( ptr++, 1); /* CONNECT command */ + PUT_BYTE( ptr++, dest_port>>8); /* destination Port */ + PUT_BYTE( ptr++, dest_port&0xFF); + /* destination IP */ + memcpy(ptr, &dest_addr.sin_addr, sizeof(dest_addr.sin_addr)); + ptr += sizeof(dest_addr.sin_addr); + if ( dest_addr.sin_addr.s_addr == 0 ) + *(ptr-1) = 1; /* fake, protocol 4a */ + /* username */ + strcpy( ptr, relay_user ); + ptr += strlen( relay_user ) +1; + /* destination host name (for protocol 4a) */ + if ( (socks_version == 4) && (dest_addr.sin_addr.s_addr == 0)) { + strcpy( ptr, dest_host ); + ptr += strlen( dest_host ) +1; + } + /* send command and get response + response is: VN:1, CD:1, PORT:2, ADDR:4 */ + atomic_out( s, buf, ptr-buf); /* send request */ + atomic_in( s, buf, 8 ); /* recv response */ + if ( (buf[1] != SOCKS4_REP_SUCCEEDED) ) { /* check reply code */ + error("Got error response: %d: '%s'.\n", + buf[1], lookup(buf[1], socks4_rep_names)); + return -1; /* failed */ + } + + /* Conguraturation, connected via SOCKS4 server! */ + return 0; +} + +int +sendf(SOCKET s, const char *fmt,...) +{ + static char buf[10240]; /* xxx, enough? */ + + va_list args; + va_start( args, fmt ); + vsprintf( buf, fmt, args ); + va_end( args ); + + report_text(">>>", buf); + if ( send(s, buf, strlen(buf), 0) == SOCKET_ERROR ) { + debug("failed to send http request. errno=%d\n", socket_errno()); + return -1; + } + return 0; +} + +const char *base64_table = +"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; + +char * +make_base64_string(const char *str) +{ + static char *buf; + unsigned char *src; + char *dst; + int bits, data, src_len, dst_len; + /* make base64 string */ + src_len = strlen(str); + dst_len = (src_len+2)/3*4; + buf = malloc(dst_len+1); + bits = data = 0; + src = (unsigned char *)str; + dst = (unsigned char *)buf; + while ( dst_len-- ) { + if ( bits < 6 ) { + data = (data << 8) | *src; + bits += 8; + if ( *src != 0 ) + src++; + } + *dst++ = base64_table[0x3F & (data >> (bits-6))]; + bits -= 6; + } + *dst = '\0'; + /* fix-up tail padding */ + switch ( src_len%3 ) { + case 1: + *--dst = '='; + case 2: + *--dst = '='; + } + return buf; +} + + +int +basic_auth( SOCKET s, const char *user, const char *pass ) +{ + char *userpass; + char *cred; + int len, ret; + + len = strlen(user)+strlen(pass)+1; + userpass = malloc(len+1); + sprintf(userpass,"%s:%s", user, pass); + cred = make_base64_string(userpass); + memset( userpass, 0, len ); + + f_report = 0; /* don't report for security */ + ret = sendf(s, "Proxy-Authorization: Basic %s\r\n", cred); + f_report = 1; + report_text(">>>", "Proxy-Authorization: Basic xxxxx\r\n"); + + memset(cred, 0, strlen(cred)); + free(cred); + + return ret; +} + +/* begin relaying via HTTP proxy + Directs CONNECT method to proxy server to connect to + destination host (and port). It may not be allowed on your + proxy server. + */ +int +begin_http_relay( SOCKET s ) +{ + char buf[1024]; + int result; + char *user = NULL, *pass = NULL; + char *auth_what; + + debug("begin_http_relay()\n"); + + if (proxy_auth_type != PROXY_AUTH_NONE) { + /* Get username/password for authentication */ + if ((user = relay_user) == NULL && + (user = getparam(ENV_HTTP_PROXY_USER)) == NULL && + (user = getparam(ENV_CONNECT_USER)) == NULL && + (user = getusername()) == NULL ) + fatal("Cannot decide username for proxy authentication."); + if ((pass = getparam(ENV_HTTP_PROXY_PASSWORD)) == NULL && + (pass = getparam(ENV_CONNECT_PASSWORD)) == NULL && + (pass = readpass("Enter proxy authentication password for %s@%s: ", + user, relay_host)) == NULL) + fatal("Cannot decide password for proxy authentication."); + user = strdup(user); + pass = strdup(pass); + } + if (sendf(s,"CONNECT %s:%d HTTP/1.0\r\n", dest_host, dest_port) < 0) + return -1; + if (proxy_auth_type == PROXY_AUTH_BASIC && basic_auth(s, user, pass) < 0) + return -1; + if (sendf(s,"\r\n") < 0) + return -1; + if ( user ) { memset(user, 0, strlen(user)); free(user); } + if ( pass ) { memset(pass, 0, strlen(pass)); free(pass); } + + /* get response */ + if ( line_input(s, buf, sizeof(buf)) < 0 ) { + debug("failed to read http response.\n"); + return -1; + } + /* check status */ + result = atoi(strchr(buf,' ')); + switch ( result ) { + case 200: + /* Conguraturation, connected via http proxy server! */ + debug("connected, start user session.\n"); + break; + case 302: /* redirect */ + do { + if (line_input(s, buf, sizeof(buf))) + break; + downcase(buf); + if (expect(buf, "Location: ")) { + relay_host = cut_token(buf, "//"); + cut_token(buf, "/"); + relay_port = atoi(cut_token(buf, ":")); + } + } while (strcmp(buf,"\r\n") != 0); + skip_all_lines(s); + return START_RETRY; + + /* We handle both 401 and 407 codes here: 401 is WWW-Authenticate, which + * not strictly the correct response, but some proxies do send this (e.g. + * Symantec's Raptor firewall) */ + case 401: /* WWW-Auth required */ + case 407: /* Proxy-Auth required */ + /** NOTE: As easy implementation, we support only BASIC scheme + and ignore realm. */ + /* If proxy_auth_type is PROXY_AUTH_BASIC and get + this result code, authentication was failed. */ + if (proxy_auth_type != PROXY_AUTH_NONE) { + error("Authentication failed.\n"); + return -1; + } + auth_what = (result == 401) ? "WWW-Authenticate:" : "Proxy-Authenticate:"; + do { + if ( line_input(s, buf, sizeof(buf)) ) { + break; + } + downcase(buf); + if (expect(buf, auth_what)) { + /* parse type and realm */ + char *scheme, *realm; + scheme = cut_token(buf, " "); + realm = cut_token(scheme, " "); + if ( scheme == NULL || realm == NULL ) { + debug("Invalid format of %s field.", auth_what); + return -1; /* fail */ + } + /* check type */ + if (expect(scheme, "basic")) { + proxy_auth_type = PROXY_AUTH_BASIC; + } else { + debug("Unsupported authentication type: %s", scheme); + return -1; + } + } + } while (strcmp(buf,"\r\n") != 0); + skip_all_lines(s); + if ( proxy_auth_type == PROXY_AUTH_NONE ) { + debug("Can't find %s in response header.", auth_what); + return -1; + } else { + return START_RETRY; + } + + default: + /* Not allowed */ + debug("http proxy is not allowed.\n"); + return -1; + } + /* skip to end of response header */ + do { + if ( line_input(s, buf, sizeof(buf) ) ) { + debug("Can't skip response headers\n"); + return -1; + } + } while ( strcmp(buf,"\r\n") != 0 ); + + return 0; +} + + +#ifdef _WIN32 +/* ddatalen() + Returns 1 if data is available, otherwise return 0 + */ +int +fddatalen( SOCKET fd ) +{ + DWORD len = 0; + struct stat st; + fstat( 0, &st ); + if ( st.st_mode & _S_IFIFO ) { + /* in case of PIPE */ + if ( !PeekNamedPipe( GetStdHandle(STD_INPUT_HANDLE), + NULL, 0, NULL, &len, NULL) ) { + if ( GetLastError() == ERROR_BROKEN_PIPE ) { + /* PIPE source is closed */ + /* read() will detects EOF */ + len = 1; + } else { + fatal("PeekNamedPipe() failed, errno=%d\n", + GetLastError()); + } + } + } else if ( st.st_mode & _S_IFREG ) { + /* in case of regular file (redirected) */ + len = 1; /* always data ready */ + } else if ( _kbhit() ) { + /* in case of console */ + len = 1; + } + return len; +} +#endif /* _WIN32 */ + +/* relay byte from stdin to socket and fro socket to stdout */ +int +do_repeater( SOCKET local_in, SOCKET local_out, SOCKET remote ) +{ + /** vars for local input data **/ + char lbuf[1024]; /* local input buffer */ + int lbuf_len; /* available data in lbuf */ + int f_local; /* read local input more? */ + /** vars for remote input data **/ + char rbuf[1024]; /* remote input buffer */ + int rbuf_len; /* available data in rbuf */ + int f_remote; /* read remote input more? */ + /** other variables **/ + int nfds, len; + fd_set *ifds, *ofds; + struct timeval *tmo; +#ifdef _WIN32 + struct timeval win32_tmo; +#endif /* _WIN32 */ + + /* repeater between stdin/out and socket */ + nfds = ((local_in local */ + if ( FD_ISSET(remote, ifds) && (rbuf_len < sizeof(rbuf)) ) { + len = recv( remote, rbuf + rbuf_len, sizeof(rbuf)-rbuf_len, 0); + if ( len == 0 ) { + debug("connection closed by peer\n"); + f_remote = 0; /* no more read from socket */ + f_local = 0; + } else if ( len == -1 ) { + if (socket_errno() != ECONNRESET) { + /* error */ + fatal("recv() faield, %d\n", socket_errno()); + } else { + debug("ECONNRESET detected\n"); + } + } else { + debug("recv %d bytes\n", len); + if ( 1 < f_debug ) /* more verbose */ + report_bytes( "<<<", rbuf, rbuf_len); + rbuf_len += len; + } + } + + /* local => remote */ + if ( FD_ISSET(local_in, ifds) && (lbuf_len < sizeof(lbuf)) ) { + if (local_type == LOCAL_SOCKET) + len = recv(local_in, lbuf + lbuf_len, + sizeof(lbuf)-lbuf_len, 0); + else + len = read(local_in, lbuf + lbuf_len, sizeof(lbuf)-lbuf_len); + if ( len == 0 ) { + /* stdin is EOF */ + debug("local input is EOF\n"); + shutdown(remote, 1); /* no-more writing */ + f_local = 0; + } else if ( len == -1 ) { + /* error on reading from stdin */ + fatal("recv() failed, errno = %d\n", errno); + } else { + /* repeat */ + lbuf_len += len; + } + } + + /* flush data in buffer to socket */ + if ( 0 < lbuf_len ) { + len = send(remote, lbuf, lbuf_len, 0); + if ( 1 < f_debug ) /* more verbose */ + report_bytes( ">>>", lbuf, lbuf_len); + if ( len == -1 ) { + fatal("send() failed, %d\n", socket_errno()); + } else if ( 0 < len ) { + /* move data on to top of buffer */ + debug("send %d bytes\n", len); + lbuf_len -= len; + if ( 0 < lbuf_len ) + memcpy( lbuf, lbuf+len, lbuf_len ); + assert( 0 <= lbuf_len ); + } + } + + /* flush data in buffer to local output */ + if ( 0 < rbuf_len ) { + if (local_type == LOCAL_SOCKET) + len = send( local_out, rbuf, rbuf_len, 0); + else + len = write( local_out, rbuf, rbuf_len); + if ( len == -1 ) { + fatal("output (local) failed, errno=%d\n", errno); + } + rbuf_len -= len; + if ( len < rbuf_len ) + memcpy( rbuf, rbuf+len, rbuf_len ); + assert( 0 <= rbuf_len ); + } + + } + + return 0; +} + + +int +accept_connection (u_short port) +{ + int sock; + int connection; + struct sockaddr_in name; + + struct sockaddr client; + int socklen; + + /* Create the socket. */ + debug("Creating source port to forward.\n"); + sock = socket (PF_INET, SOCK_STREAM, 0); + if (sock < 0) + fatal("socket() failed, errno=%d\n", socket_errno()); + + /* Give the socket a name. */ + name.sin_family = AF_INET; + name.sin_port = htons (port); + name.sin_addr.s_addr = htonl (INADDR_ANY); + if (bind (sock, (struct sockaddr *) &name, sizeof (name)) < 0) + fatal ("bind() failed, errno=%d\n", socket_errno()); + + if (listen( sock, 1) < 0) + fatal ("listen() failed, errno=%d\n", socket_errno()); + + socklen = sizeof(client); + connection = accept( sock, &client, &socklen); + if ( connection < 0 ) + fatal ("accept() failed, errno=%d\n", socket_errno()); + + shutdown(sock, 2); + + return connection; +} + + + +/** Main of program **/ +int +main( int argc, char **argv ) +{ + int ret; + SOCKET remote; /* socket */ + SOCKET local_in; /* Local input */ + SOCKET local_out; /* Local output */ +#ifdef _WIN32 + WSADATA wsadata; + WSAStartup( 0x101, &wsadata); +#endif /* _WIN32 */ + + /* initialization */ + make_revstr(); + getarg( argc, argv ); + debug("Program is $Revision$\n"); + + /* Open local_in and local_out if forwarding a port */ + if ( local_type == LOCAL_SOCKET ) { + /* Relay between local port and destination */ + local_in = local_out = accept_connection( local_port ); + } else { + /* Relay between stdin/stdout and desteination */ + local_in = 0; + local_out = 1; +#ifdef _WIN32 + _setmode(local_in, O_BINARY); + _setmode(local_out, O_BINARY); +#endif + } + +retry: +#ifndef _WIN32 + if (0 < connect_timeout) + set_timeout (connect_timeout); +#endif /* not _WIN32 */ + + /* make connection */ + if ( relay_method == METHOD_DIRECT ) { + remote = open_connection (dest_host, dest_port); + if ( remote == SOCKET_ERROR ) + fatal( "Unable to connect to destination host, errno=%d\n", + socket_errno()); + } else { + remote = open_connection (relay_host, relay_port); + if ( remote == SOCKET_ERROR ) + fatal( "Unable to connect to relay host, errno=%d\n", + socket_errno()); + } + + /** resolve destination host (SOCKS) **/ + if (relay_method == METHOD_SOCKS && + socks_resolve == RESOLVE_LOCAL && + local_resolve (dest_host, &dest_addr, &socks_ns) < 0) { + fatal("Unknown host: %s", dest_host); + } + + /** relay negociation **/ + switch ( relay_method ) { + case METHOD_SOCKS: + if ( ((socks_version == 5) && (begin_socks5_relay(remote) < 0)) || + ((socks_version == 4) && (begin_socks4_relay(remote) < 0)) ) + fatal( "failed to begin relaying via SOCKS.\n"); + break; + + case METHOD_HTTP: + ret = begin_http_relay(remote); + switch (ret) { + case START_ERROR: + fatal("failed to begin relaying via HTTP.\n"); + case START_OK: + break; + case START_RETRY: + /* retry with authentication */ + goto retry; + } + break; + } + debug("connected\n"); + +#ifndef _WIN32 + if (0 < connect_timeout) + set_timeout (0); +#endif /* not _WIN32 */ + + /* main loop */ + debug ("start relaying.\n"); + do_repeater(local_in, local_out, remote); + debug ("relaying done.\n"); + closesocket(remote); + if ( local_type == LOCAL_SOCKET) + closesocket(local_in); +#ifdef _WIN32 + WSACleanup(); +#endif /* _WIN32 */ + debug ("that's all, bye.\n"); + + return 0; +} + +/* ------------------------------------------------------------ + Local Variables: + compile-command: "cc connect.c -o connect" + fill-column: 74 + comment-column: 48 + End: + ------------------------------------------------------------ */ + +/*** end of connect.c ***/