1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
|
/*
INSPECTSOCKS - Part of the tsocks package
This utility can be used to determine the protocol
level of a SOCKS server.
Copyright (C) 2000 Shaun Clowes
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., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
/* Global configuration variables */
char *progname = "inspectsocks"; /* Name for error msgs */
int defaultport = 1080; /* Default SOCKS port */
/* Header Files */
#include <config.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <string.h>
#include <strings.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <errno.h>
#include <common.h>
int send_request(struct sockaddr_in *server, void *req,
int reqlen, void *rep, int replen);
int main(int argc, char *argv[]) {
char *usage = "Usage: <socks server name/ip> [portno]";
char req[9];
char resp[100];
unsigned short int portno = defaultport;
int ver = 0;
int read_bytes;
struct sockaddr_in server;
if ((argc < 2) || (argc > 3)) {
show_msg(MSGERR, "Invalid number of arguments\n");
show_msg(MSGERR, "%s\n", usage);
exit(1);
}
switch (argc) {
case 3:
portno = (unsigned short int)
strtol(argv[2], (char **) 0, 10);
if ((portno == 0) || (errno == EINVAL)) {
show_msg(MSGERR, "%s\n", usage);
exit(1);
}
case 2:
if ((server.sin_addr.s_addr = resolve_ip(argv[1], 1,HOSTNAMES))
== -1) {
show_msg(MSGERR, "Invalid IP/host specified (%s)\n", argv[1]);
show_msg(MSGERR, "%s\n", usage);
exit(1);
}
}
server.sin_family = AF_INET; /* host byte order */
server.sin_port = htons(portno); /* short, network byte order */
bzero(&(server.sin_zero), 8);/* zero the rest of the struct */
/* Now, we send a SOCKS V5 request which happens to be */
/* the same size as the smallest possible SOCKS V4 */
/* request. In this packet we specify we have 7 auth */
/* methods but specify them all as NO AUTH. */
bzero(req, sizeof(req));
req[0] = '\x05';
req[1] = '\x07';
read_bytes = send_request(&server, req,
sizeof(req), resp, sizeof(resp));
if (read_bytes > 0) {
if ((int) resp[0] == 0) {
ver = 4;
} else if ((int) resp[0] == 5) {
ver = 5;
}
if (ver != 0) {
printf("Reply indicates server is a version "
"%d socks server\n", ver);
} else {
show_msg(MSGERR, "Invalid SOCKS version reply (%d), "
"probably not a socks server\n",
ver);
}
exit(0);
}
/* Hmmm.... disconnected so try a V4 request */
printf("Server disconnected V5 request, trying V4\n");
req[0] = '\x04';
req[1] = '\x01';
read_bytes = send_request(&server, req,
sizeof(req), resp, sizeof(resp));
if (read_bytes > 0) {
if ((int) resp[0] == 0) {
ver = 4;
}
if (ver == 4) {
printf("Reply indicates server is a version "
"4 socks server\n");
} else {
show_msg(MSGERR, "Invalid SOCKS version reply (%d), "
"probably not a socks server\n",
(int) resp[0]);
}
exit(0);
} else {
show_msg(MSGERR, "Server disconnected, probably not a "
"socks server\n");
}
return(0);
}
int send_request(struct sockaddr_in *server, void *req,
int reqlen, void *rep, int replen) {
int sock;
int rc;
if ((sock = socket(server->sin_family, SOCK_STREAM, 0)) < 0)
{
show_msg(MSGERR, "Could not create socket (%s)\n",
strerror(errno));
exit(1);
}
if (connect(sock, (struct sockaddr *) server,
sizeof(struct sockaddr_in)) != -1) {
} else {
show_msg(MSGERR, "Connect failed! (%s)\n",
strerror(errno));
exit(1);
}
if (send(sock, (void *) req, reqlen,0) < 0) {
show_msg(MSGERR, "Could not send to server (%s)\n",
strerror(errno));
exit(1);
}
/* Now wait for reply */
if ((rc = recv(sock, (void *) rep, replen, 0)) < 0) {
show_msg(MSGERR, "Could not read from server\n",
strerror(errno));
exit(1);
}
close(sock);
return(rc);
}
|
