9b241efe722bc8d4f6e926a9077e0e32797b73e2
[paraslash.git] / client_common.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_common.c common functions of para_client and para_audiod */
20
21 #include "para.h"
22 #include "list.h"
23 #include "sched.h"
24 #include "client.cmdline.h"
25 #include "crypt.h"
26 #include "rc4.h"
27 #include "net.h"
28 #include "fd.h"
29 #include "string.h"
30 #include "client.cmdline.h"
31 #include "client.h"
32 #include "error.h"
33
34 void rc4_send(unsigned long len, const unsigned char *indata,
35 unsigned char *outdata, void *private_data)
36 {
37 struct private_client_data *pcd = private_data;
38 RC4(&pcd->rc4_send_key, len, indata, outdata);
39 }
40
41 void rc4_recv(unsigned long len, const unsigned char *indata,
42 unsigned char *outdata, void *private_data)
43 {
44 struct private_client_data *pcd = private_data;
45 RC4(&pcd->rc4_recv_key, len, indata, outdata);
46 }
47
48
49 void client_close(struct private_client_data *pcd)
50 {
51 if (pcd)
52 return;
53 if (pcd->fd >= 0)
54 close(pcd->fd);
55 free(pcd->user);
56 free(pcd->config_file);
57 free(pcd->key_file);
58 free(pcd);
59 }
60
61 int client_parse_config(int argc, char *argv[],
62 struct private_client_data **pcd_ptr)
63 {
64 char *home = para_homedir();
65 struct stat statbuf;
66 int ret;
67 struct private_client_data *pcd =
68 para_calloc(sizeof(struct private_client_data));
69
70 pcd->fd = -1;
71 client_cmdline_parser(argc, argv, &pcd->conf);
72 ret = - E_CLIENT_SYNTAX;
73 if (!pcd->conf.inputs_num)
74 goto out;
75 pcd->user = pcd->conf.user_given?
76 para_strdup(pcd->conf.user_arg) : para_logname();
77
78 pcd->key_file = pcd->conf.key_file_given?
79 para_strdup(pcd->conf.key_file_arg) :
80 make_message("%s/.paraslash/key.%s", home, pcd->user);
81
82 pcd->config_file = pcd->conf.config_file_given?
83 para_strdup(pcd->conf.config_file_arg) :
84 make_message("%s/.paraslash/client.conf", home);
85 ret = stat(pcd->config_file, &statbuf);
86 if (ret && pcd->conf.config_file_given) {
87 ret = -E_NO_CONFIG;
88 goto out;
89 }
90 if (!ret)
91 client_cmdline_parser_configfile(pcd->config_file,
92 &pcd->conf, 0, 0, 0);
93 ret = 1;
94 *pcd_ptr = pcd;
95 PARA_INFO_LOG(
96 "current loglevel: %d\n"
97 "using config_file: %s\n"
98 "using key_file: %s\n"
99 "connecting to %s:%d\n" ,
100 pcd->conf.loglevel_arg,
101 pcd->config_file,
102 pcd->key_file,
103 pcd->conf.hostname_arg, pcd->conf.server_port_arg
104 );
105 out:
106 free(home);
107 if (ret < 0)
108 client_close(pcd);
109 return ret;
110 }
111
112 void client_pre_select(struct sched *s, struct task *t)
113 {
114 struct private_client_data *pcd = t->private_data;
115
116 t->ret = 1;
117 pcd->check_r = 0;
118 pcd->check_w = 0;
119 if (pcd->fd < 0)
120 return;
121 switch (pcd->status) {
122 case CL_CONNECTED:
123 case CL_SENT_AUTH:
124 case CL_SENT_CH_RESPONSE:
125 case CL_SENT_COMMAND:
126 para_fd_set(pcd->fd, &s->rfds, &s->max_fileno);
127 pcd->check_r = 1;
128 return;
129
130 case CL_RECEIVED_WELCOME:
131 case CL_RECEIVED_CHALLENGE:
132 case CL_RECEIVED_PROCEED:
133 para_fd_set(pcd->fd, &s->wfds, &s->max_fileno);
134 pcd->check_w = 1;
135 return;
136
137 case CL_RECEIVING_SERVER_OUTPUT:
138 if (pcd->loaded < CLIENT_BUFSIZE - 1) {
139 para_fd_set(pcd->fd, &s->rfds, &s->max_fileno);
140 pcd->check_r = 1;
141 }
142 return;
143 case CL_SENDING_STDIN:
144 if (*pcd->in_loaded) {
145 PARA_INFO_LOG("loaded: %zd\n", *pcd->in_loaded);
146 para_fd_set(pcd->fd, &s->wfds, &s->max_fileno);
147 pcd->check_w = 1;
148 } else {
149 if (*pcd->in_eof) {
150 t->ret = -E_INPUT_EOF;
151 s->timeout.tv_sec = 0;
152 s->timeout.tv_usec = 1;
153 }
154 }
155 return;
156 }
157 }
158
159 static ssize_t client_recv_buffer(struct private_client_data *pcd)
160 {
161 ssize_t ret = recv_buffer(pcd->fd, pcd->buf + pcd->loaded,
162 CLIENT_BUFSIZE - pcd->loaded);
163 if (!ret)
164 return -E_SERVER_EOF;
165 if (ret > 0)
166 pcd->loaded += ret;
167 return ret;
168
169 }
170
171 void client_post_select(struct sched *s, struct task *t)
172 {
173 struct private_client_data *pcd = t->private_data;
174
175 // PARA_INFO_LOG("status %d\n", pcd->status);
176 t->ret = 1;
177 if (pcd->fd < 0)
178 return;
179 if (!pcd->check_r && !pcd->check_w)
180 return;
181 if (pcd->check_r && !FD_ISSET(pcd->fd, &s->rfds))
182 return;
183 if (pcd->check_w && !FD_ISSET(pcd->fd, &s->wfds))
184 return;
185 switch (pcd->status) {
186 case CL_CONNECTED: /* receive welcome message */
187 t->ret = client_recv_buffer(pcd);
188 if (t->ret > 0)
189 pcd->status = CL_RECEIVED_WELCOME;
190 return;
191 case CL_RECEIVED_WELCOME: /* send auth command */
192 sprintf(pcd->buf, "auth %s%s", pcd->conf.plain_given?
193 "" : "rc4 ", pcd->user);
194 PARA_INFO_LOG("--> %s\n", pcd->buf);
195 t->ret = send_buffer(pcd->fd, pcd->buf);
196 if (t->ret >= 0)
197 pcd->status = CL_SENT_AUTH;
198 return;
199 case CL_SENT_AUTH: /* receive challenge number */
200 pcd->loaded = 0;
201 t->ret = client_recv_buffer(pcd);
202 if (t->ret < 0)
203 return;
204 if (t->ret != 64) {
205 t->ret = -E_INVALID_CHALLENGE;
206 PARA_ERROR_LOG("received the following: %s\n", pcd->buf);
207 return;
208 }
209 PARA_INFO_LOG("%s", "<-- [challenge]\n");
210 /* decrypt challenge number */
211 t->ret = para_decrypt_challenge(pcd->key_file, &pcd->challenge_nr,
212 (unsigned char *) pcd->buf, 64);
213 if (t->ret > 0)
214 pcd->status = CL_RECEIVED_CHALLENGE;
215 return;
216 case CL_RECEIVED_CHALLENGE: /* send decrypted challenge */
217 PARA_INFO_LOG("--> %lu\n", pcd->challenge_nr);
218 t->ret = send_va_buffer(pcd->fd, "%s%lu", CHALLENGE_RESPONSE_MSG,
219 pcd->challenge_nr);
220 if (t->ret > 0)
221 pcd->status = CL_SENT_CH_RESPONSE;
222 return;
223 case CL_SENT_CH_RESPONSE: /* read server response */
224 {
225 size_t bytes_received;
226 unsigned char rc4_buf[2 * RC4_KEY_LEN] = "";
227 pcd->loaded = 0;
228 t->ret = client_recv_buffer(pcd);
229 if (t->ret < 0)
230 return;
231 bytes_received = t->ret;
232 PARA_DEBUG_LOG("++++ server info ++++\n%s\n++++ end of server "
233 "info ++++\n", pcd->buf);
234 /* check if server has sent "Proceed" message */
235 t->ret = -E_CLIENT_AUTH;
236 if (!strstr(pcd->buf, PROCEED_MSG))
237 return;
238 t->ret = 1;
239 pcd->status = CL_RECEIVED_PROCEED;
240 if (bytes_received < PROCEED_MSG_LEN + 32)
241 return;
242 PARA_INFO_LOG("%s", "decrypting session key\n");
243 t->ret = para_decrypt_buffer(pcd->key_file, rc4_buf,
244 (unsigned char *)pcd->buf + PROCEED_MSG_LEN + 1,
245 bytes_received - PROCEED_MSG_LEN - 1);
246 if (t->ret < 0)
247 return;
248 RC4_set_key(&pcd->rc4_send_key, RC4_KEY_LEN, rc4_buf);
249 RC4_set_key(&pcd->rc4_recv_key, RC4_KEY_LEN, rc4_buf + RC4_KEY_LEN);
250 enable_crypt(pcd->fd, rc4_recv, rc4_send, pcd);
251 }
252 case CL_RECEIVED_PROCEED: /* concat args and send command */
253 {
254 int i;
255 char *command = NULL;
256 for (i = 0; i < pcd->conf.inputs_num; i++) {
257 char *tmp = command;
258 command = make_message("%s\n%s", command?
259 command : "", pcd->conf.inputs[i]);
260 free(tmp);
261 }
262 command = para_strcat(command, EOC_MSG "\n");
263 PARA_DEBUG_LOG("--> %s\n", command);
264 t->ret = send_buffer(pcd->fd, command);
265 free(command);
266 if (t->ret > 0)
267 pcd->status = CL_SENT_COMMAND;
268 return;
269 }
270 case CL_SENT_COMMAND:
271 pcd->loaded = 0;
272 t->ret = client_recv_buffer(pcd);
273 if (t->ret < 0)
274 return;
275 t->ret = -E_HANDSHAKE_COMPLETE;
276 if (strstr(pcd->buf, AWAITING_DATA_MSG))
277 pcd->status = CL_SENDING_STDIN;
278 else
279 pcd->status = CL_RECEIVING_SERVER_OUTPUT;
280 return;
281 case CL_SENDING_STDIN: /* FIXME: might block */
282 PARA_INFO_LOG("loaded: %zd\n", *pcd->in_loaded);
283 t->ret = send_bin_buffer(pcd->fd, pcd->inbuf, *pcd->in_loaded);
284 if (t->ret <= 0) {
285 if (!t->ret)
286 t->ret = 1;
287 return;
288 }
289 *pcd->in_loaded = 0; /* FIXME: short writes */
290 return;
291 case CL_RECEIVING_SERVER_OUTPUT:
292 t->ret = client_recv_buffer(pcd);
293 return;
294 }
295
296 }
297
298 int client_open(struct private_client_data *pcd)
299 {
300 int ret;
301 struct hostent *he;
302 struct sockaddr_in their_addr;
303
304 /* get the host info */
305 PARA_NOTICE_LOG("getting host info of %s\n",
306 pcd->conf.hostname_arg);
307 ret = get_host_info(pcd->conf.hostname_arg, &he);
308 if (ret < 0)
309 goto out;
310 /* get new socket */
311 ret = get_socket();
312 if (ret < 0)
313 goto out;
314 pcd->fd = ret;
315 /* init their_addr */
316 init_sockaddr(&their_addr, pcd->conf.server_port_arg, he);
317 /* connect */
318 PARA_NOTICE_LOG("connecting to %s\n", pcd->conf.hostname_arg);
319 ret = para_connect(pcd->fd, &their_addr);
320 if (ret < 0)
321 goto out;
322 pcd->status = CL_CONNECTED;
323 ret = mark_fd_nonblock(pcd->fd);
324 if (ret < 0)
325 goto out;
326 pcd->task.pre_select = client_pre_select;
327 pcd->task.post_select = client_post_select;
328 pcd->task.private_data = pcd;
329 sprintf(pcd->task.status, "client");
330 register_task(&pcd->task);
331 ret = 1;
332 out:
333 return ret;
334 }