0380d5678b3aae84d34bdb62838c3f9cd475cf82
[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 RC4_KEY rc4_recv_key;
42 RC4_KEY rc4_send_key;
43
44 char *in_buf;
45 size_t *in_loaded;
46 char *out_buf;
47 size_t *out_loaded;
48 };
49
50 INIT_CLIENT_ERRLISTS;
51
52 static struct private_client_data *pcd;
53
54 /*
55 * client log function
56 */
57 void para_log(int ll, const char* fmt,...)
58 {
59 va_list argp;
60
61 /* ignore log message if loglevel is not high enough */
62 if (pcd && ll < pcd->conf.loglevel_arg)
63 return;
64 va_start(argp, fmt);
65 vfprintf(stderr, fmt, argp);
66 va_end(argp);
67 }
68
69 static void client_close(struct private_client_data *pcd)
70 {
71 if (pcd)
72 return;
73 if (pcd->fd >= 0)
74 close(pcd->fd);
75 free(pcd->user);
76 free(pcd->config_file);
77 free(pcd->key_file);
78 free(pcd);
79 }
80
81 static int client_parse_config(int argc, char *argv[],
82 struct private_client_data **pcd_ptr)
83 {
84 char *home = para_homedir();
85 struct stat statbuf;
86 int ret;
87 struct private_client_data *p =
88 para_calloc(sizeof(struct private_client_data));
89
90 p->fd = -1;
91 cmdline_parser(argc, argv, &p->conf);
92 ret = - E_CLIENT_SYNTAX;
93 if (!p->conf.inputs_num)
94 goto out;
95 p->user = p->conf.user_given?
96 para_strdup(p->conf.user_arg) : para_logname();
97
98 p->key_file = p->conf.key_file_given?
99 para_strdup(p->conf.key_file_arg) :
100 make_message("%s/.paraslash/key.%s", home, p->user);
101
102 p->config_file = p->conf.config_file_given?
103 para_strdup(p->conf.config_file_arg) :
104 make_message("%s/.paraslash/client.conf", home);
105 ret = stat(p->config_file, &statbuf);
106 if (ret && p->conf.config_file_given) {
107 ret = -E_NO_CONFIG;
108 goto out;
109 }
110 if (!ret)
111 cmdline_parser_configfile(p->config_file, &p->conf, 0, 0, 0);
112 ret = 1;
113 out:
114 free(home);
115 if (ret < 0)
116 client_close(p);
117 else
118 *pcd_ptr = p;
119 return ret;
120 }
121
122 static void rc4_send(unsigned long len, const unsigned char *indata,
123 unsigned char *outdata)
124 {
125 RC4(&pcd->rc4_send_key, len, indata, outdata);
126 }
127
128 static void rc4_recv(unsigned long len, const unsigned char *indata,
129 unsigned char *outdata)
130 {
131 RC4(&pcd->rc4_recv_key, len, indata, outdata);
132 }
133
134 static void append_str(char **data, const char* append)
135 {
136 if (*data) {
137 char *tmp = make_message("%s\n%s", *data, append);
138 free(*data);
139 *data = tmp;
140 } else
141 *data = para_strdup(append);
142 }
143
144
145 static int send_stdin(int fd)
146 {
147 char buf[8192];
148 int ret;
149
150 PARA_NOTICE_LOG("%s", "sending stdin\n");
151 for (;;) {
152 ret = read(STDIN_FILENO, buf, sizeof(buf));
153 if (ret <= 0)
154 return ret;
155 ret = send_bin_buffer(fd, buf, ret);
156 if (ret < 0)
157 return ret;
158 }
159 return 1;
160 }
161
162 /*
163 * MAIN
164 */
165 int main(int argc, char *argv[])
166 {
167
168 int numbytes, i, received, ret;
169 struct hostent *he;
170 struct sockaddr_in their_addr;
171 char *command = NULL;
172 char buf[8192];
173 char *auth_str;
174 long unsigned challenge_nr;
175 unsigned char rc4_buf[2 * RC4_KEY_LEN] = "";
176
177 ret = client_parse_config(argc, argv, &pcd);
178 if (ret < 0)
179 goto out;
180 if (pcd->conf.loglevel_arg <= NOTICE)
181 cmdline_parser_print_version();
182 PARA_INFO_LOG(
183 "current loglevel: %d\n"
184 "using config_file: %s\n"
185 "using key_file: %s\n"
186 "connecting to %s:%d\n",
187 pcd->conf.loglevel_arg,
188 pcd->config_file,
189 pcd->key_file,
190 pcd->conf.hostname_arg,
191 pcd->conf.server_port_arg
192 );
193 /* concat args */
194 for (i = 0; i < pcd->conf.inputs_num; i++)
195 append_str(&command, pcd->conf.inputs[i]);
196 /* get the host info */
197 PARA_NOTICE_LOG("getting host info of %s\n",
198 pcd->conf.hostname_arg);
199 ret = get_host_info(pcd->conf.hostname_arg, &he);
200 if (ret < 0)
201 goto out;
202 /* get new socket */
203 ret = get_socket();
204 if (ret < 0)
205 goto out;
206 pcd->fd = ret;
207 /* init their_addr */
208 init_sockaddr(&their_addr, pcd->conf.server_port_arg, he);
209 /* connect */
210 PARA_NOTICE_LOG("connecting to %s\n", pcd->conf.hostname_arg);
211 ret = para_connect(pcd->fd, &their_addr);
212 if (ret < 0)
213 goto out;
214 /* receive welcome message */
215 ret = recv_buffer(pcd->fd, buf, sizeof(buf));
216 if (ret < 0)
217 goto out;
218 /* send auth command */
219 auth_str = make_message("auth %s%s", pcd->conf.plain_given? "" : "rc4 ",
220 pcd->user);
221 PARA_INFO_LOG("<-- %s--> %s\n", buf, auth_str);
222 ret = send_buffer(pcd->fd, auth_str);
223 if (ret < 0)
224 goto out;
225 /* receive challenge number */
226 ret = recv_buffer(pcd->fd, buf, sizeof(buf));
227 if (ret < 0)
228 goto out;
229 if (ret != 64) {
230 ret = -E_INVALID_CHALLENGE;
231 PARA_ERROR_LOG("received the following: %s\n", buf);
232 goto out;
233 }
234 PARA_INFO_LOG("%s", "<-- [challenge]\n");
235 /* decrypt challenge number */
236 ret = para_decrypt_challenge(pcd->key_file, &challenge_nr,
237 (unsigned char *) buf, 64);
238 if (ret < 0)
239 goto out;
240 /* send decrypted challenge */
241 PARA_INFO_LOG("--> %lu\n", challenge_nr);
242 ret = send_va_buffer(pcd->fd, "%s%lu", CHALLENGE_RESPONSE_MSG, challenge_nr);
243 if (ret < 0)
244 goto out;
245 /* wait for approval */
246 PARA_NOTICE_LOG("%s", "waiting for approval from server\n");
247 ret = recv_buffer(pcd->fd, buf, sizeof(buf));
248 if (ret < 0)
249 goto out;
250 numbytes = ret;
251 PARA_INFO_LOG("++++ server info ++++\n%s\n++++ end of server "
252 "info ++++\n", buf);
253 /* check if server has sent "Proceed" message */
254 ret = -E_CLIENT_AUTH;
255 if (!strstr(buf, PROCEED_MSG))
256 goto out;
257 if (numbytes >= PROCEED_MSG_LEN + 32) {
258 PARA_INFO_LOG("%s", "decrypting session key\n");
259 ret = para_decrypt_buffer(pcd->key_file, rc4_buf,
260 (unsigned char *)buf + PROCEED_MSG_LEN + 1,
261 numbytes - PROCEED_MSG_LEN - 1);
262 if (ret < 0)
263 goto out;
264 RC4_set_key(&pcd->rc4_send_key, RC4_KEY_LEN, rc4_buf);
265 RC4_set_key(&pcd->rc4_recv_key, RC4_KEY_LEN, rc4_buf + RC4_KEY_LEN);
266 PARA_INFO_LOG("rc4 encryption activated: %x:%x:%x:%x\n",
267 rc4_buf[0], rc4_buf[1], rc4_buf[2], rc4_buf[3]);
268 enable_crypt(pcd->fd, rc4_recv, rc4_send);
269 }
270 /* send command */
271 PARA_INFO_LOG("--> %s\n", command);
272 ret = send_buffer(pcd->fd, command);
273 if (ret < 0)
274 goto out;
275 free(command);
276 command = NULL;
277 ret = send_buffer(pcd->fd, EOC_MSG "\n");
278 if (ret < 0)
279 goto out;
280 PARA_NOTICE_LOG("%s", "command sent.\n");
281 received = 0;
282 for (;;) {
283 ret = recv_bin_buffer(pcd->fd, buf, sizeof(buf) - 1);
284 if (ret <= 0) {
285 if (!ret)
286 PARA_NOTICE_LOG("%s", "connection closed by peer\n");
287 goto out;
288 }
289 buf[ret] = '\0';
290 numbytes = ret;
291 if (!received && strstr(buf, AWAITING_DATA_MSG)) {
292 ret = send_stdin(pcd->fd);
293 goto out;
294 }
295 received = 1;
296 ret = write(STDOUT_FILENO, buf, numbytes);
297 if (ret != numbytes) {
298 ret = -E_SHORT_CLIENT_WRITE;
299 goto out;
300 }
301 }
302 client_close(pcd);
303 out:
304 if (ret < 0)
305 PARA_ERROR_LOG("%s\n", PARA_STRERROR(-ret));
306 return ret >= 0? EXIT_SUCCESS: EXIT_FAILURE;
307 }