/* packet-socks.c * Routines for socks versions 4 &5 packet dissection * Copyright 2000, Jeffrey C. Foster * * $Id: packet-socks.c,v 1.18 2001/01/10 10:59:11 guy Exp $ * * Ethereal - Network traffic analyzer * By Gerald Combs * Copyright 1998 Gerald Combs * * * 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. * * * The Version 4 decode is based on SOCKS4.protocol and SOCKS4A.protocol. * The Version 5 decoder is based upon rfc-1928 * The Version 5 User/Password authentication is based on rfc-1929. * * See http://www.socks.nec.com/socksprot.html for these and other documents * * Revisions: * * 2001-01-08 JCFoster Fixed problem with NULL pointer for hash data. * Now test and exit if hash_info is null. */ /* Possible enhancements - * * Add GSS-API authentication per rfc-1961 * Add CHAP authentication * Decode FLAG bits per * http://www.socks.nec.com/draft/draft-ietf-aft-socks-pro-v-04.txt * In call_next_dissector, could load the destination address into the * pi structure before calling next dissector. * remove display_string or at least make it use protocol identifiers * socks_hash_entry_t needs to handle V5 address type and domain names */ #ifdef HAVE_CONFIG_H # include "config.h" #endif #ifdef HAVE_SYS_TYPES_H # include #endif #ifdef HAVE_NETINET_IN_H # include #endif #include #include #include #ifdef NEED_SNPRINTF_H # include "snprintf.h" #endif #include "packet.h" #include "resolv.h" #include "globals.h" #include "alignment.h" #include "conversation.h" #include "packet-tcp.h" #include "packet-udp.h" #include "strutil.h" #define CHECK_PACKET_LENGTH(X) if (!BYTES_ARE_IN_FRAME(offset, X)){ \ proto_tree_add_text(tree, NullTVB, offset, 0, "*** FRAME TOO SHORT ***"); \ return; } #define compare_packet(X) (X == (fd->num)) #define get_packet_ptr (fd->num) #define row_pointer_type guint32 #define TCP_PORT_SOCKS 1080 /**************** Socks commands ******************/ #define CONNECT_COMMAND 1 #define BIND_COMMAND 2 #define UDP_ASSOCIATE_COMMAND 3 #define PING_COMMAND 0x80 #define TRACERT_COMMAND 0x81 /********** V5 Authentication methods *************/ #define NO_AUTHENTICATION 0 #define GSS_API_AUTHENTICATION 1 #define USER_NAME_AUTHENTICATION 2 #define CHAP_AUTHENTICATION 3 #define AUTHENTICATION_FAILED 0xff /*********** Header field identifiers *************/ static int proto_socks = -1; static int ett_socks = -1; static int ett_socks_auth = -1; static int ett_socks_name = -1; static int hf_socks_ver = -1; static int hf_socks_ip_dst = -1; static int hf_socks_ip6_dst = -1; static int hf_user_name = -1; static int hf_socks_dstport = -1; static int hf_socks_command = -1; /************* State Machine names ***********/ enum SockState { None = 0, Connecting, V4UserNameWait, V4NameWait, V5Command, V5Reply, V5BindReply, UserNameAuth, GssApiAuth, AuthReply, Done }; typedef struct { int state; int version; int command; int grant; gint32 port; gint32 udp_port; gint32 udp_remote_port; int connect_offset; row_pointer_type v4_name_row; row_pointer_type v4_user_name_row; row_pointer_type connect_row; row_pointer_type cmd_reply_row; row_pointer_type bind_reply_row; row_pointer_type command_row; row_pointer_type auth_method_row; row_pointer_type user_name_auth_row; guint32 start_done_row; guint32 dst_addr; /* this needs to handle IPv6 */ }socks_hash_entry_t; static char *address_type_table[] = { "Unknown", "IPv4", "Unknown", "Domain Name", "IPv6", "Unknown" }; /* String table for the V4 reply status messages */ static char *reply_table_v4[] = { "Granted", "Rejected or Failed", "Rejected because SOCKS server cannot connect to identd on the client", "Rejected because the client program and identd report different user-ids", "Unknown" }; /* String table for the V5 reply status messages */ static char *reply_table_v5[] = { "Succeeded", "General SOCKS server failure", "Connection not allowed by ruleset", "Network unreachable", "Host unreachable", "Connection refused", "TTL expired", "Command not supported", "Address type not supported", "Unknown" }; #define socks_hash_init_count 20 #define socks_hash_val_length (sizeof(socks_hash_entry_t)) static GMemChunk *socks_vals = NULL; /************************* Support routines ***************************/ static int display_string( const u_char *pd, int offset, frame_data *fd, proto_tree *tree, char *label){ /* display a string with a length, characters encoding */ /* they are displayed under a tree with the name in Label variable */ /* return the length of the string and the length byte */ proto_tree *name_tree; proto_item *ti; char temp[ 256]; int length = GBYTE( pd, offset); if (!BYTES_ARE_IN_FRAME(offset, 8)){ proto_tree_add_text(tree, NullTVB, offset, 0, "*** FRAME TOO SHORT ***"); return 0; } strncpy( temp, &pd[ offset + 1], length); temp[ length ] = 0; ti = proto_tree_add_text(tree, NullTVB, offset, length + 1, "%s: %s" , label, temp); name_tree = proto_item_add_subtree(ti, ett_socks_name); proto_tree_add_text( name_tree, NullTVB, offset, 1, "Length: %d", length); ++offset; proto_tree_add_text( name_tree, NullTVB, offset, length, "String: %s", temp); return length + 1; } static char *get_auth_method_name( guint Number){ /* return the name of the authenication method */ if ( Number == 0) return "No authentication"; if ( Number == 1) return "GSSAPI"; if ( Number == 2) return "Username/Password"; if ( Number == 3) return "Chap"; if (( Number >= 4) && ( Number <= 0x7f))return "IANA assigned"; if (( Number >= 0x80) && ( Number <= 0xfe)) return "private method"; if ( Number == 0xff) return "no acceptable method"; /* shouldn't reach here */ return "Bad method number (not 0-0xff)"; } static char *get_command_name( guint Number){ /* return the name of the command as a string */ if ( Number == 0) return "Unknow"; if ( Number == 1) return "Connect"; if ( Number == 2) return "Bind"; if ( Number == 3) return "UdpAssociate"; if ( Number == 0x80) return "Ping"; if ( Number == 0x81) return "Traceroute"; return "Unknown"; } static int display_address( const u_char *pd, int offset, frame_data *fd, proto_tree *tree) { /* decode and display the v5 address, return offset of next byte */ int a_type = GBYTE( pd, offset); proto_tree_add_text( tree, NullTVB, offset, 1, "Address Type: %d (%s)", a_type, address_type_table[ MAX( 0, MIN( a_type, array_length( address_type_table)-1))]); ++offset; if ( a_type == 1){ /* IPv4 address */ if (!BYTES_ARE_IN_FRAME(offset, 4)) proto_tree_add_text(tree, NullTVB, offset, 0, "*** FRAME TOO SHORT ***"); proto_tree_add_ipv4( tree, hf_socks_ip_dst, NullTVB, offset, 4, GWORD( pd, offset)); offset += 4; } else if ( a_type == 3){ /* domain name address */ offset += display_string( pd, offset, fd, tree, "Remote name"); } else if ( a_type == 4){ /* IPv6 address */ if (!BYTES_ARE_IN_FRAME(offset, 16)) proto_tree_add_text(tree, NullTVB, offset, 0, "*** FRAME TOO SHORT ***"); proto_tree_add_ipv6( tree, hf_socks_ip6_dst, NullTVB, offset, 4, &pd[offset]); offset += 16; } return offset; } static int get_address_v5( const u_char *pd, int offset, socks_hash_entry_t *hash_info) { /* decode the v5 address and return offset of next byte */ /*$$$ this needs to handle IPV6 and domain name addresses */ int a_type = GBYTE( pd, offset++); if ( a_type == 1){ /* IPv4 address */ if ( hash_info) hash_info->dst_addr = GWORD( pd, offset); offset += 4; } else if ( a_type == 4) /* IPv6 address */ offset += 16; else if ( a_type == 3) /* domain name address */ offset += GBYTE( pd, offset) + 1; return offset; } /********************* V5 UDP Associate handlers ***********************/ static void socks_udp_dissector( const u_char *pd, int offset, frame_data *fd, proto_tree *tree) { /* Conversation dissector called from UDP dissector. Decode and display */ /* the socks header, the pass the rest of the data to the udp port */ /* decode routine to handle the payload. */ guint32 *ptr; socks_hash_entry_t *hash_info; conversation_t *conversation; proto_tree *socks_tree; proto_item *ti; tvbuff_t *tvb; conversation = find_conversation( &pi.src, &pi.dst, pi.ptype, pi.srcport, pi.destport, 0); g_assert( conversation); /* should always find a conversation */ hash_info = (socks_hash_entry_t*)conversation->data; if (check_col(fd, COL_PROTOCOL)) col_set_str(fd, COL_PROTOCOL, "Socks"); if (check_col(fd, COL_INFO)) col_add_fstr(fd, COL_INFO, "Version: 5, UDP Associated packet"); if ( tree) { ti = proto_tree_add_protocol_format( tree, proto_socks, NullTVB, offset, END_OF_FRAME, "Socks" ); socks_tree = proto_item_add_subtree(ti, ett_socks); CHECK_PACKET_LENGTH( 3); proto_tree_add_text( socks_tree, NullTVB, offset, 2, "Reserved"); offset += 2; proto_tree_add_text( socks_tree, NullTVB, offset, 1, "Fragment Number: %d", GBYTE( pd,offset)); ++offset; offset = display_address( pd, offset, fd, socks_tree); hash_info->udp_remote_port = pntohs( &pd[ offset]); CHECK_PACKET_LENGTH( 2); proto_tree_add_uint( socks_tree, hf_socks_dstport, NullTVB, offset, 2, hash_info->udp_remote_port); offset += 2; } else { /* no tree, skip past the socks header */ CHECK_PACKET_LENGTH( 3); offset += 3; offset = get_address_v5( pd,offset, 0) + 2; } /* set pi src/dst port and call the udp sub-dissector lookup */ if ( pi.srcport == hash_info->port) ptr = &pi.destport; else ptr = &pi.srcport; *ptr = hash_info->udp_remote_port; tvb = tvb_create_from_top(0); decode_udp_ports( tvb, offset, &pi, tree, pi.srcport, pi.destport); *ptr = hash_info->udp_port; } void new_udp_conversation( socks_hash_entry_t *hash_info){ conversation_t *conversation = conversation_new( &pi.src, &pi.dst, PT_UDP, hash_info->udp_port, hash_info->port, hash_info, 0); g_assert( conversation); old_conversation_set_dissector(conversation, socks_udp_dissector); } /**************** Protocol Tree Display routines ******************/ void display_socks_v4( const u_char *pd, int offset, frame_data *fd, proto_tree *parent, proto_tree *tree, socks_hash_entry_t *hash_info) { /* Display the protocol tree for the V5 version. This routine uses the */ /* stored conversation information to decide what to do with the row. */ /* Per packet information would have been better to do this, but we */ /* didn't have that when I wrote this. And I didn't expect this to get */ /* so messy. */ int command; /* Display command from client */ if (compare_packet( hash_info->connect_row)){ CHECK_PACKET_LENGTH( 8); proto_tree_add_text( tree, NullTVB, offset, 1, "Version: %u ", hash_info->version); ++offset; command = GBYTE( pd, offset); proto_tree_add_text( tree, NullTVB, offset, 1, "Command: %u (%s)", command, get_command_name( command)); ++offset; /* Do remote port */ proto_tree_add_uint( tree, hf_socks_dstport, NullTVB, offset, 2, pntohs( &pd[ offset])); offset += 2; /* Do destination address */ proto_tree_add_ipv4( tree, hf_socks_ip_dst, NullTVB, offset, 4, GWORD( pd, offset)); offset += 4; /*$$ check this, needs to do length checking */ /* display user name */ proto_tree_add_string( tree, hf_user_name, NullTVB, offset, strlen( &pd[offset]) + 1, &pd[offset]); } /*Display command response from server*/ else if ( compare_packet( hash_info->cmd_reply_row)){ CHECK_PACKET_LENGTH( 8); proto_tree_add_text( tree, NullTVB, offset, 1, "Version: %u (should be 0) ", GBYTE( pd, offset)); ++offset; /* Do results code */ proto_tree_add_text( tree, NullTVB, offset, 1, "Result Code: %u (%s)", GBYTE( pd, offset) , reply_table_v4[ MAX(0, MIN( GBYTE( pd, offset) - 90, 4))]); ++offset; /* Do remote port */ proto_tree_add_uint( tree, hf_socks_dstport, NullTVB, offset, 2, pntohs( &pd[ offset])); offset += 2;; /* Do remote address */ proto_tree_add_ipv4( tree, hf_socks_ip_dst, NullTVB, offset, 4, GWORD( pd, offset)); } else if ( compare_packet( hash_info->v4_user_name_row)){ /*$$ check this, needs to do length checking */ proto_tree_add_text( tree, NullTVB, offset, strlen( &pd[offset]), "User Name: %s", &pd[offset]); } } void display_socks_v5( const u_char *pd, int offset, frame_data *fd, proto_tree *parent, proto_tree *tree, socks_hash_entry_t *hash_info) { /* Display the protocol tree for the version. This routine uses the */ /* stored conversation information to decide what to do with the row. */ /* Per packet information would have been better to do this, but we */ /* didn't have that when I wrote this. And I didn't expect this to get */ /* so messy. */ int i, command; guint temp; char *AuthMethodStr; if (compare_packet( hash_info->connect_row)){ proto_tree *AuthTree; proto_item *ti; CHECK_PACKET_LENGTH( 2); /* Do version */ proto_tree_add_uint( tree, hf_socks_ver, NullTVB, offset, 1, hash_info->version); ++offset; temp = GBYTE( pd, offset); /* Get Auth method count */ /* build auth tree */ ti = proto_tree_add_text( tree, NullTVB, offset, 1, "Client Authentication Methods"); AuthTree = proto_item_add_subtree(ti, ett_socks_auth); proto_tree_add_text( AuthTree, NullTVB, offset, 1, "Count: %u ", temp); ++offset; CHECK_PACKET_LENGTH( temp); for( i = 0; i < temp; ++i) { AuthMethodStr = get_auth_method_name( GBYTE( pd, offset + i)); proto_tree_add_text( AuthTree, NullTVB, offset + i, 1, "Method[%d]: %u (%s)", i, GBYTE( pd, offset + i), AuthMethodStr); } return; } /* Get accepted auth method */ else if (compare_packet( hash_info->auth_method_row)) { ++offset; CHECK_PACKET_LENGTH( 1); proto_tree_add_text( tree, NullTVB, offset, 1, "Accepted Auth Method: 0x%0x (%s)", GBYTE( pd, offset), get_auth_method_name( GBYTE( pd, offset))); return; } /* handle user/password auth */ else if (compare_packet( hash_info->user_name_auth_row)) { proto_tree_add_text( tree, NullTVB, offset, 1, "Version: %u ", hash_info->version); ++offset; /* process user name */ offset += display_string( pd, offset, fd, tree, "User name"); /* process password */ offset += display_string( pd, offset, fd, tree, "Password"); } /* command to the server */ /* command response from server */ else if ((compare_packet( hash_info->command_row)) || (compare_packet( hash_info->cmd_reply_row)) || (compare_packet( hash_info->bind_reply_row))){ proto_tree_add_text( tree, NullTVB, offset, 1, "Version: %u ", hash_info->version); CHECK_PACKET_LENGTH( 1); ++offset; command = GBYTE( pd, offset); if (compare_packet( hash_info->command_row)) proto_tree_add_text( tree, NullTVB, offset, 1, "Command: %u (%s)", command, get_command_name( command)); else proto_tree_add_text( tree, NullTVB, offset, 1, "Status: %d (%s)", GBYTE( pd, offset), reply_table_v5[ MAX( 0, MIN(GBYTE( pd, offset) - 90, 9))]); ++offset; proto_tree_add_text( tree, NullTVB, offset, 1, "Reserved: 0x%0x (should = 0x00)", GBYTE( pd, offset)); ++offset; offset = display_address( pd, offset, fd, tree); CHECK_PACKET_LENGTH( 2); /* Do remote port */ proto_tree_add_text( tree, NullTVB, offset, 2, "%sPort: %d", (compare_packet( hash_info->bind_reply_row) ? "Remote Host " : ""), pntohs( &pd[ offset])); } } /**************** Decoder State Machines ******************/ static guint state_machine_v4( socks_hash_entry_t *hash_info, const u_char *pd, int offset, frame_data *fd) { /* Decode V4 protocol. This is done on the first pass through the */ /* list. Based upon the current state, decode the packet and determine */ /* what the next state should be. If we had per packet information, */ /* this would be the place to load them up. */ if ( hash_info->state == None) { /* new connection */ if (check_col(fd, COL_INFO)) col_append_str(fd, COL_INFO, " Connect to server request"); hash_info->state = Connecting; /* change state */ hash_info->command = GBYTE( pd, offset + 1); /* get remote port */ if ( hash_info->command == CONNECT_COMMAND) hash_info->port = pntohs( &pd[ offset + 2]); /* get remote address */ hash_info->dst_addr = GWORD( pd, offset + 4); /* save the packet pointer */ hash_info->connect_row = get_packet_ptr; /* skip past this stuff */ hash_info->connect_offset = offset + 8; offset += 8; if ( offset == pi.len) /* if no user name */ /* change state */ hash_info->state = V4UserNameWait; hash_info->connect_offset += strlen( &pd[ offset]) + 1; if ( !hash_info->dst_addr){ /* if no dest address */ /* if more data */ if ( hash_info->connect_offset < pi.len ) { /*$$$ copy remote name here ??? */ hash_info->state = Connecting; } else hash_info->state = V4NameWait; } /* waiting for V4 user name */ }else if ( hash_info->state == V4UserNameWait){ if (check_col(fd, COL_INFO)) col_append_str(fd, COL_INFO, " Connect Request (User name)"); hash_info->v4_user_name_row = get_packet_ptr; /*$$$ may need to check for domain name here */ hash_info->state = Connecting; } /* waiting for V4 domain name */ else if ( hash_info->state == V4NameWait){ hash_info->v4_name_row = get_packet_ptr; hash_info->state = Connecting; } else if ( hash_info->state == Connecting){ if (check_col(fd, COL_INFO)) col_append_str(fd, COL_INFO, " Connect Response"); /* save packet pointer */ hash_info->cmd_reply_row = get_packet_ptr; hash_info->state = Done; /* change state */ offset = offset + 8; } return offset; } static void state_machine_v5( socks_hash_entry_t *hash_info, const u_char *pd, int offset, frame_data *fd) { /* Decode V5 protocol. This is done on the first pass through the */ /* list. Based upon the current state, decode the packet and determine */ /* what the next state should be. If we had per packet information, */ /* this would be the place to load them up. */ int temp; if ( hash_info->state == None) { if (check_col(fd, COL_INFO)) col_append_str(fd, COL_INFO, " Connect to server request"); hash_info->state = Connecting; /* change state */ hash_info->connect_row = get_packet_ptr; if (!BYTES_ARE_IN_FRAME(offset, 1)){ hash_info->state = Done; /* change state */ return; } temp = GBYTE( pd, offset + 1); /* skip past auth methods */ offset = hash_info->connect_offset = offset + 1 + temp; } else if ( hash_info->state == Connecting){ guint AuthMethod = GBYTE( pd, offset + 1); if (check_col(fd, COL_INFO)) col_append_str(fd, COL_INFO, " Connect to server response"); hash_info->auth_method_row = get_packet_ptr; if ( AuthMethod == NO_AUTHENTICATION) hash_info->state = V5Command; else if ( AuthMethod == USER_NAME_AUTHENTICATION) hash_info->state = UserNameAuth; else if ( AuthMethod == GSS_API_AUTHENTICATION) /*$$$ should be this hash_info->state = GssApiAuth; */ hash_info->state = Done; else hash_info->state = Done; /*Auth failed or error*/ } else if ( hash_info->state == V5Command) { /* Handle V5 Command */ guint temp; if (!BYTES_ARE_IN_FRAME(offset, 1)){ hash_info->state = Done; /* change state */ return; } hash_info->command = GBYTE( pd, offset + 1); /* get command */ if (check_col(fd, COL_INFO)) col_append_fstr(fd, COL_INFO, " Command Request - %s", get_command_name(hash_info->command)); hash_info->state = V5Reply; hash_info->command_row = get_packet_ptr; offset += 3; /* skip to address type */ offset = get_address_v5( pd, offset, hash_info); if (!BYTES_ARE_IN_FRAME(offset, 1)){ hash_info->state = Done; return; } temp = GBYTE( pd, offset); if (( hash_info->command == CONNECT_COMMAND) || ( hash_info->command == UDP_ASSOCIATE_COMMAND)) /* get remote port */ hash_info->port = pntohs( &pd[ offset]); } else if ( hash_info->state == V5Reply) { /* V5 Command Reply */ if (check_col(fd, COL_INFO)) col_append_fstr(fd, COL_INFO, " Command Response - %s", get_command_name(hash_info->command)); hash_info->cmd_reply_row = get_packet_ptr; if (( hash_info->command == CONNECT_COMMAND) || (hash_info->command == PING_COMMAND) || (hash_info->command == TRACERT_COMMAND)) hash_info->state = Done; else if ( hash_info->command == BIND_COMMAND) hash_info->state = V5BindReply; else if ( hash_info->command == UDP_ASSOCIATE_COMMAND){ offset += 3; /* skip to address type */ offset = get_address_v5( pd, offset, hash_info); /* save server udp port and create upd conversation */ if (!BYTES_ARE_IN_FRAME(offset, 2)){ hash_info->state = Done; return; } hash_info->udp_port = pntohs( &pd[ offset]); new_udp_conversation( hash_info); /*$$ may need else statement to handle unknows and generate error message */ } } else if ( hash_info->state == V5BindReply) { /* V5 Bind Second Reply */ if (check_col(fd, COL_INFO)) col_append_str(fd, COL_INFO, " Command Response: Bind remote host info"); hash_info->bind_reply_row = get_packet_ptr; hash_info->state = Done; } else if ( hash_info->state == UserNameAuth) { /* Handle V5 User Auth*/ if (check_col(fd, COL_INFO)) col_append_str(fd, COL_INFO, " User authentication response"); hash_info->user_name_auth_row = get_packet_ptr; hash_info->state = AuthReply; } else if ( hash_info->state == AuthReply){ /* V5 User Auth reply */ hash_info->cmd_reply_row = get_packet_ptr; if (check_col(fd, COL_INFO)) col_append_str(fd, COL_INFO, " User authentication reply"); hash_info->state = V5Command; } } static void display_ping_and_tracert( const u_char *pd, int offset, frame_data *fd, proto_tree *tree, socks_hash_entry_t *hash_info) { /* Display the ping/trace_route conversation */ const u_char *data, *dataend; const u_char *lineend, *eol; int linelen; /* handle the end command */ if ( pi.destport == TCP_PORT_SOCKS){ if (check_col(fd, COL_INFO)) col_append_str(fd, COL_INFO, ", Terminate Request"); if ( tree) proto_tree_add_text(tree, NullTVB, offset, 1, (hash_info->command == PING_COMMAND) ? "Ping: End command" : "Traceroute: End command"); } else{ /* display the PING or Traceroute results */ if (check_col(fd, COL_INFO)) col_append_str(fd, COL_INFO, ", Results"); if ( tree){ proto_tree_add_text(tree, NullTVB, offset, END_OF_FRAME, (hash_info->command == PING_COMMAND) ? "Ping Results:" : "Traceroute Results"); data = &pd[offset]; dataend = data + END_OF_FRAME; while (data < dataend) { lineend = find_line_end(data, dataend, &eol); linelen = lineend - data; proto_tree_add_text( tree, NullTVB, offset, linelen, format_text(data, linelen)); offset += linelen; data = lineend; } } } } static void call_next_dissector( const u_char *pd, int offset, frame_data *fd, proto_tree *tree, socks_hash_entry_t *hash_info) { /* Display the results for PING and TRACERT extensions or */ /* Call TCP dissector for the port that was passed during the */ /* connect process */ /* Load pointer to pi.XXXport depending upon the direction, change */ /* pi port to the remote port, call next dissecotr to decode the */ /* payload, and restore the pi port after that is done. */ guint32 *ptr; tvbuff_t *tvb; if (( hash_info->command == PING_COMMAND) || ( hash_info->command == TRACERT_COMMAND)) display_ping_and_tracert( pd, offset, fd, tree, hash_info); else { /* call the tcp port decoder to handle the payload */ /*$$$ may want to load dest address here */ if ( pi.destport == TCP_PORT_SOCKS) ptr = &pi.destport; else ptr = &pi.srcport; *ptr = hash_info->port; tvb = tvb_create_from_top(0); decode_tcp_ports( tvb, offset, &pi, tree, pi.srcport, pi.destport); *ptr = TCP_PORT_SOCKS; } } static void dissect_socks(const u_char *pd, int offset, frame_data *fd, proto_tree *tree) { proto_tree *socks_tree; proto_item *ti; socks_hash_entry_t *hash_info; conversation_t *conversation; OLD_CHECK_DISPLAY_AS_DATA(proto_socks, pd, offset, fd, tree); conversation = find_conversation( &pi.src, &pi.dst, pi.ptype, pi.srcport, pi.destport, 0); if ( conversation){ /* conversation found */ hash_info = conversation->data; if ( !hash_info){ /* exit if bad value */ old_dissect_data(pd, offset, fd, tree); return; } /* new conversation create local data structure */ } else { hash_info = g_mem_chunk_alloc(socks_vals); hash_info->start_done_row = G_MAXINT; hash_info->state = None; hash_info->port = -1; hash_info->version = GBYTE( pd, offset); /* get version*/ if (( hash_info->version != 4) && /* error test version */ ( hash_info->version != 5)) hash_info->state = Done; conversation = conversation_new( &pi.src, &pi.dst, pi.ptype, pi.srcport, pi.destport, hash_info, 0); /* set dissector for now */ old_conversation_set_dissector(conversation, dissect_socks); } /* display summary window information */ if (check_col(fd, COL_PROTOCOL)) col_set_str(fd, COL_PROTOCOL, "Socks"); if (check_col(fd, COL_INFO)){ if (( hash_info->version == 4) || ( hash_info->version == 5)){ col_add_fstr(fd, COL_INFO, "Version: %d", hash_info->version); } else /* unknown version display error */ col_set_str(fd, COL_INFO, "Unknown"); if ( hash_info->command == PING_COMMAND) col_append_str(fd, COL_INFO, ", Ping Req"); if ( hash_info->command == TRACERT_COMMAND) col_append_str(fd, COL_INFO, ", Traceroute Req"); if ( hash_info->port != -1) col_append_fstr(fd, COL_INFO, ", Remote Port: %d", hash_info->port); } /* run state machine if needed */ if ((hash_info->state != Done) && ( !fd->flags.visited)){ if ( hash_info->version == 4) state_machine_v4( hash_info, pd, offset, fd); else if ( hash_info->version == 5) state_machine_v5( hash_info, pd, offset, fd); if (hash_info->state == Done) { /* if done now */ hash_info->start_done_row = fd->num; } } /* if proto tree, decode and display */ if (tree) { ti = proto_tree_add_item( tree, proto_socks, NullTVB, offset, END_OF_FRAME, FALSE ); socks_tree = proto_item_add_subtree(ti, ett_socks); if ( hash_info->version == 4) display_socks_v4( pd, offset, fd, tree, socks_tree, hash_info); else if ( hash_info->version == 5) display_socks_v5( pd, offset, fd, tree, socks_tree, hash_info); /* if past startup, add the faked stuff */ if ( fd->num > hash_info->start_done_row){ /* add info to tree */ proto_tree_add_text( socks_tree, NullTVB, offset, 0, "Command: %d (%s)", hash_info->command, get_command_name(hash_info->command)); proto_tree_add_ipv4( socks_tree, hf_socks_ip_dst, NullTVB, offset, 0, hash_info->dst_addr); /* no fake address for ping & traceroute */ if (( hash_info->command != PING_COMMAND) && ( hash_info->command != TRACERT_COMMAND)){ proto_tree_add_uint( socks_tree, hf_socks_dstport, NullTVB, offset, 0, hash_info->port); } } } /* call next dissector if ready */ if ( fd->num > hash_info->start_done_row){ call_next_dissector( pd, offset, fd, tree, hash_info); } } static void socks_reinit( void){ /* Do the cleanup work when a new pass through the packet list is */ /* performed. Reset the highest row seen counter and re-initialize the */ /* conversation memory chunks. */ if (socks_vals) g_mem_chunk_destroy(socks_vals); socks_vals = g_mem_chunk_new("socks_vals", socks_hash_val_length, socks_hash_init_count * socks_hash_val_length, G_ALLOC_AND_FREE); } void proto_register_socks( void){ /*** Prep the socks protocol, register it and a initialization routine */ /* to clear the hash stuff. */ static gint *ett[] = { &ett_socks, &ett_socks_auth, &ett_socks_name }; static hf_register_info hf[] = { { &hf_socks_ver, { "Version", "socks.ver", FT_UINT8, BASE_NONE, NULL, 0x0, "" } }, { &hf_socks_ip_dst, { "Remote Address", "socks.dst", FT_IPv4, BASE_NONE, NULL, 0x0, "" } }, { &hf_socks_ip6_dst, { "Remote Address", "socks.dstV6", FT_IPv6, BASE_NONE, NULL, 0x0, "" } }, { &hf_user_name, { "User Name", "socks.username", FT_STRING, BASE_NONE, NULL, 0x0, "" } }, { &hf_socks_dstport, { "Remote Port", "socks.dstport", FT_UINT16, BASE_DEC, NULL, 0x0, "" } }, { &hf_socks_command, { "Command", "socks.command", FT_UINT16, BASE_DEC, NULL, 0x0, "" } } }; proto_socks = proto_register_protocol ( "Socks Protocol", "Socks", "socks"); proto_register_field_array(proto_socks, hf, array_length(hf)); proto_register_subtree_array(ett, array_length(ett)); register_init_routine( &socks_reinit); /* register re-init routine */ } void proto_reg_handoff_socks(void) { /* dissector install routine */ old_dissector_add("tcp.port", TCP_PORT_SOCKS, dissect_socks, proto_socks); }