dba99a28749850ed3f797b8859cdbc8de008920d
[paraslash.git] / client.c
1 /*
2 * Copyright (C) 1997-2006 Andre Noll <maan@systemlinux.org>
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111, USA.
17 */
18
19 /** \file client.c the client program used to connect to para_server */
20
21 #include "para.h"
22 #include "config.h"
23 #include "client.cmdline.h"
24 #include "crypt.h"
25 #include "rc4.h"
26 #include <openssl/rc4.h>
27 #include "net.h"
28 #include "string.h"
29 #include "error.h"
30
31 enum {CL_CONNECTED, CL_SENT_AUTH, CL_RECEIVED_CHALLENGE, CL_SENT_CH_RESPONSE,
32 CL_RECEIVED_PROCEED, CL_SENT_COMMAND, CL_SENDING_STDIN, CL_RECV_DATA};
33
34 struct private_client_data {
35 int status;
36 int fd;
37 struct client_args_info conf;
38 char *config_file;
39 char *key_file;
40 char *user;
41 char *in_buf;
42 size_t *in_loaded;
43 char *out_buf;
44 size_t *out_loaded;
45 };
46
47 INIT_CLIENT_ERRLISTS;
48
49 static struct private_client_data *pcd;
50
51 /*
52 * client log function
53 */
54 void para_log(int ll, const char* fmt,...)
55 {
56 va_list argp;
57
58 /* ignore log message if loglevel is not high enough */
59 if (pcd && ll < pcd->conf.loglevel_arg)
60 return;
61 va_start(argp, fmt);
62 vfprintf(stderr, fmt, argp);
63 va_end(argp);
64 }
65
66 static void client_close(struct private_client_data *pcd)
67 {
68 if (pcd)
69 return;
70 if (pcd->fd >= 0)
71 close(pcd->fd);
72 free(pcd->user);
73 free(pcd->config_file);
74 free(pcd->key_file);
75 free(pcd);
76 }
77
78 static int client_parse_config(int argc, char *argv[],
79 struct private_client_data **pcd_ptr)
80 {
81 char *home = para_homedir();
82 struct stat statbuf;
83 int ret;
84 struct private_client_data *p =
85 para_calloc(sizeof(struct private_client_data));
86
87 p->fd = -1;
88 cmdline_parser(argc, argv, &p->conf);
89 ret = - E_CLIENT_SYNTAX;
90 if (!p->conf.inputs_num)
91 goto out;
92 p->user = p->conf.user_given?
93 para_strdup(p->conf.user_arg) : para_logname();
94
95 p->key_file = p->conf.key_file_given?
96 para_strdup(p->conf.key_file_arg) :
97 make_message("%s/.paraslash/key.%s", home, p->user);
98
99 p->config_file = p->conf.config_file_given?
100 para_strdup(p->conf.config_file_arg) :
101 make_message("%s/.paraslash/client.conf", home);
102 ret = stat(p->config_file, &statbuf);
103 if (ret && p->conf.config_file_given) {
104 ret = -E_NO_CONFIG;
105 goto out;
106 }
107 if (!ret)
108 cmdline_parser_configfile(p->config_file, &p->conf, 0, 0, 0);
109 ret = 1;
110 out:
111 free(home);
112 if (ret < 0)
113 client_close(p);
114 else
115 *pcd_ptr = p;
116 return ret;
117 }
118
119 static RC4_KEY rc4_recv_key;
120 static RC4_KEY rc4_send_key;
121 static unsigned char rc4_buf[2 * RC4_KEY_LEN];
122
123 static void rc4_send(unsigned long len, const unsigned char *indata, unsigned char *outdata)
124 {
125 RC4(&rc4_send_key, len, indata, outdata);
126 }
127
128 static void rc4_recv(unsigned long len, const unsigned char *indata, unsigned char *outdata)
129 {
130 RC4(&rc4_recv_key, len, indata, outdata);
131 }
132 void (*crypt_function_recv)(unsigned long len, const unsigned char *indata, unsigned char *outdata);
133 void (*crypt_function_send)(unsigned long len, const unsigned char *indata, unsigned char *outdata);
134
135
136 static void append_str(char **data, const char* append)
137 {
138 if (*data) {
139 char *tmp = make_message("%s\n%s", *data, append);
140 free(*data);
141 *data = tmp;
142 } else
143 *data = para_strdup(append);
144 }
145
146
147 static int send_stdin(int fd)
148 {
149 char buf[8192];
150 int ret;
151
152 PARA_NOTICE_LOG("%s", "sending stdin\n");
153 for (;;) {
154 ret = read(STDIN_FILENO, buf, sizeof(buf));
155 if (ret <= 0)
156 return ret;
157 ret = send_bin_buffer(fd, buf, ret);
158 if (ret < 0)
159 return ret;
160 }
161 return 1;
162 }
163
164 /*
165 * MAIN
166 */
167 int main(int argc, char *argv[])
168 {
169
170 int numbytes, i, received, ret;
171 struct hostent *he;
172 struct sockaddr_in their_addr;
173 char *command = NULL;
174 char buf[8192];
175 char *auth_str;
176 long unsigned challenge_nr;
177
178 ret = client_parse_config(argc, argv, &pcd);
179 if (ret < 0)
180 goto out;
181 if (pcd->conf.loglevel_arg <= NOTICE)
182 cmdline_parser_print_version();
183 PARA_INFO_LOG(
184 "current loglevel: %d\n"
185 "using config_file: %s\n"
186 "using key_file: %s\n"
187 "connecting to %s:%d\n",
188 pcd->conf.loglevel_arg,
189 pcd->config_file,
190 pcd->key_file,
191 pcd->conf.hostname_arg,
192 pcd->conf.server_port_arg
193 );
194 /* concat args */
195 for (i = 0; i < pcd->conf.inputs_num; i++)
196 append_str(&command, pcd->conf.inputs[i]);
197 crypt_function_recv = NULL;
198 crypt_function_send = NULL;
199 /* get the host info */
200 PARA_NOTICE_LOG("getting host info of %s\n",
201 pcd->conf.hostname_arg);
202 ret = get_host_info(pcd->conf.hostname_arg, &he);
203 if (ret < 0)
204 goto out;
205 /* get new socket */
206 ret = get_socket();
207 if (ret < 0)
208 goto out;
209 pcd->fd = ret;
210 /* init their_addr */
211 init_sockaddr(&their_addr, pcd->conf.server_port_arg, he);
212 /* connect */
213 PARA_NOTICE_LOG("connecting to %s\n", pcd->conf.hostname_arg);
214 ret = para_connect(pcd->fd, &their_addr);
215 if (ret < 0)
216 goto out;
217 /* receive welcome message */
218 ret = recv_buffer(pcd->fd, buf, sizeof(buf));
219 if (ret < 0)
220 goto out;
221 /* send auth command */
222 auth_str = make_message("auth %s%s", pcd->conf.plain_given? "" : "rc4 ",
223 pcd->user);
224 PARA_INFO_LOG("<-- %s--> %s\n", buf, auth_str);
225 ret = send_buffer(pcd->fd, auth_str);
226 if (ret < 0)
227 goto out;
228 /* receive challenge number */
229 ret = recv_buffer(pcd->fd, buf, sizeof(buf));
230 if (ret < 0)
231 goto out;
232 if (ret != 64) {
233 ret = -E_INVALID_CHALLENGE;
234 PARA_ERROR_LOG("received the following: %s\n", buf);
235 goto out;
236 }
237 PARA_INFO_LOG("%s", "<-- [challenge]\n");
238 /* decrypt challenge number */
239 ret = para_decrypt_challenge(pcd->key_file, &challenge_nr,
240 (unsigned char *) buf, 64);
241 if (ret < 0)
242 goto out;
243 /* send decrypted challenge */
244 PARA_INFO_LOG("--> %lu\n", challenge_nr);
245 ret = send_va_buffer(pcd->fd, "%s%lu", CHALLENGE_RESPONSE_MSG, challenge_nr);
246 if (ret < 0)
247 goto out;
248 /* wait for approval */
249 PARA_NOTICE_LOG("%s", "waiting for approval from server\n");
250 ret = recv_buffer(pcd->fd, buf, sizeof(buf));
251 if (ret < 0)
252 goto out;
253 numbytes = ret;
254 PARA_INFO_LOG("++++ server info ++++\n%s\n++++ end of server "
255 "info ++++\n", buf);
256 /* check if server has sent "Proceed" message */
257 ret = -E_CLIENT_AUTH;
258 if (!strstr(buf, PROCEED_MSG))
259 goto out;
260 if (numbytes >= PROCEED_MSG_LEN + 32) {
261 PARA_INFO_LOG("%s", "decrypting session key\n");
262 ret = para_decrypt_buffer(pcd->key_file, rc4_buf,
263 (unsigned char *)buf + PROCEED_MSG_LEN + 1,
264 numbytes - PROCEED_MSG_LEN - 1);
265 if (ret < 0)
266 goto out;
267 RC4_set_key(&rc4_send_key, RC4_KEY_LEN, rc4_buf);
268 RC4_set_key(&rc4_recv_key, RC4_KEY_LEN, rc4_buf + RC4_KEY_LEN);
269 PARA_INFO_LOG("rc4 encrytion activated: %x:%x:%x:%x\n",
270 rc4_buf[0], rc4_buf[1], rc4_buf[2], rc4_buf[3]);
271 crypt_function_recv = rc4_recv;
272 crypt_function_send = rc4_send;
273 }
274 /* send command */
275 PARA_INFO_LOG("--> %s\n", command);
276 ret = send_buffer(pcd->fd, command);
277 if (ret < 0)
278 goto out;
279 free(command);
280 command = NULL;
281 ret = send_buffer(pcd->fd, EOC_MSG "\n");
282 if (ret < 0)
283 goto out;
284 PARA_NOTICE_LOG("%s", "command sent.\n");
285 received = 0;
286 for (;;) {
287 ret = recv_bin_buffer(pcd->fd, buf, sizeof(buf) - 1);
288 if (ret <= 0) {
289 if (!ret)
290 PARA_NOTICE_LOG("%s", "connection closed by peer\n");
291 goto out;
292 }
293 buf[ret] = '\0';
294 numbytes = ret;
295 if (!received && strstr(buf, AWAITING_DATA_MSG)) {
296 ret = send_stdin(pcd->fd);
297 goto out;
298 }
299 received = 1;
300 ret = write(STDOUT_FILENO, buf, numbytes);
301 if (ret != numbytes) {
302 ret = -E_SHORT_CLIENT_WRITE;
303 goto out;
304 }
305 }
306 client_close(pcd);
307 out:
308 if (ret < 0)
309 PARA_ERROR_LOG("%s\n", PARA_STRERROR(-ret));
310 return ret >= 0? EXIT_SUCCESS: EXIT_FAILURE;
311 }