Remove some unnecessary includes.
[paraslash.git] / client_common.c
1 /*
2 * Copyright (C) 1997-2011 Andre Noll <maan@systemlinux.org>
3 *
4 * Licensed under the GPL v2. For licencing details see COPYING.
5 */
6
7 /** \file client_common.c Common functions of para_client and para_audiod. */
8
9 #include <regex.h>
10 #include <sys/types.h>
11
12 #include "para.h"
13 #include "error.h"
14 #include "list.h"
15 #include "sched.h"
16 #include "client.cmdline.h"
17 #include "crypt.h"
18 #include "net.h"
19 #include "fd.h"
20 #include "string.h"
21 #include "client.cmdline.h"
22 #include "client.h"
23 #include "buffer_tree.h"
24
25 /** The size of the receiving buffer. */
26 #define CLIENT_BUFSIZE 4000
27
28 /**
29 * Close the connection to para_server and free all resources.
30 *
31 * \param ct Pointer to the client data.
32 *
33 * \sa client_open.
34 */
35 void client_close(struct client_task *ct)
36 {
37 if (!ct)
38 return;
39 if (ct->scc.fd >= 0)
40 close(ct->scc.fd);
41 sc_free(ct->scc.recv);
42 sc_free(ct->scc.send);
43 free(ct->user);
44 free(ct->config_file);
45 free(ct->key_file);
46 client_cmdline_parser_free(&ct->conf);
47 free(ct);
48 }
49
50 /**
51 * The preselect hook for server commands.
52 *
53 * \param s Pointer to the scheduler.
54 * \param t Pointer to the task struct for this command.
55 *
56 * The task pointer must contain a pointer to the initialized client data
57 * structure as it is returned by client_open().
58 *
59 * This function checks the state of the connection and adds the file descriptor
60 * of the connection to the read or write fd set of \a s accordingly.
61 *
62 * \sa register_task() client_open(), struct sched, struct task.
63 */
64 static void client_pre_select(struct sched *s, struct task *t)
65 {
66 int ret;
67 struct client_task *ct = container_of(t, struct client_task, task);
68 struct btr_node *btrn = ct->btrn;
69
70 if (ct->scc.fd < 0)
71 return;
72 switch (ct->status) {
73 case CL_CONNECTED:
74 case CL_SENT_AUTH:
75 case CL_SENT_CH_RESPONSE:
76 case CL_SENT_COMMAND:
77 para_fd_set(ct->scc.fd, &s->rfds, &s->max_fileno);
78 return;
79
80 case CL_RECEIVED_WELCOME:
81 case CL_RECEIVED_PROCEED:
82 para_fd_set(ct->scc.fd, &s->wfds, &s->max_fileno);
83 return;
84
85 case CL_RECEIVING:
86 ret = btr_node_status(btrn, 0, BTR_NT_ROOT);
87 if (ret != 0) {
88 if (ret < 0)
89 sched_min_delay(s);
90 else
91 para_fd_set(ct->scc.fd, &s->rfds,
92 &s->max_fileno);
93 }
94 return;
95 case CL_SENDING:
96 ret = btr_node_status(btrn, 0, BTR_NT_LEAF);
97 if (ret != 0) {
98 if (ret < 0)
99 sched_min_delay(s);
100 else
101 para_fd_set(ct->scc.fd, &s->wfds,
102 &s->max_fileno);
103 }
104 return;
105 }
106 }
107
108 static int client_recv_buffer(struct client_task *ct, fd_set *rfds,
109 char *buf, size_t sz, size_t *n)
110 {
111 int ret;
112
113 if (ct->status < CL_SENT_CH_RESPONSE)
114 return read_nonblock(ct->scc.fd, buf, sz, rfds, n);
115
116 *n = 0;
117 ret = sc_recv_buffer(&ct->scc, buf, sz);
118 /*
119 * sc_recv_buffer is used with blocking fds elsewhere, so it
120 * does not use the nonblock-API. Therefore we need to
121 * check for EOF and EAGAIN.
122 */
123 if (ret == 0)
124 return -E_SERVER_EOF;
125 if (ret == -ERRNO_TO_PARA_ERROR(EAGAIN))
126 return 0;
127 if (ret < 0)
128 return ret;
129 *n = ret;
130 return 0;
131 }
132
133 /**
134 * The post select hook for client commands.
135 *
136 * \param s Pointer to the scheduler.
137 * \param t Pointer to the task struct for this command.
138 *
139 * Depending on the current state of the connection and the status of the read
140 * and write fd sets of \a s, this function performs the necessary steps to
141 * authenticate the connection, to send the command given by \a t->private_data
142 * and to receive para_server's output, if any.
143 *
144 * \sa struct sched, struct task.
145 */
146 static void client_post_select(struct sched *s, struct task *t)
147 {
148 struct client_task *ct = container_of(t, struct client_task, task);
149 struct btr_node *btrn = ct->btrn;
150 int ret = 0;
151 size_t n;
152 char buf[CLIENT_BUFSIZE];
153
154 t->error = 0;
155 if (ct->scc.fd < 0)
156 return;
157 switch (ct->status) {
158 case CL_CONNECTED: /* receive welcome message */
159 ret = client_recv_buffer(ct, &s->rfds, buf, sizeof(buf), &n);
160 if (ret < 0 || n == 0)
161 goto out;
162 ct->status = CL_RECEIVED_WELCOME;
163 return;
164 case CL_RECEIVED_WELCOME: /* send auth command */
165 sprintf(buf, AUTH_REQUEST_MSG "%s", ct->user);
166 PARA_INFO_LOG("--> %s\n", buf);
167 if (!FD_ISSET(ct->scc.fd, &s->wfds))
168 return;
169 ret = send_buffer(ct->scc.fd, buf);
170 if (ret < 0)
171 goto out;
172 ct->status = CL_SENT_AUTH;
173 return;
174 case CL_SENT_AUTH:
175 /*
176 * Receive challenge and session keys, decrypt the challenge and
177 * send back the hash of the decrypted challenge.
178 */
179 {
180 /* decrypted challenge/session key buffer */
181 unsigned char crypt_buf[1024];
182 /* the SHA1 of the decrypted challenge */
183 unsigned char challenge_hash[HASH_SIZE];
184
185 ret = client_recv_buffer(ct, &s->rfds, buf, sizeof(buf), &n);
186 if (ret < 0 || n == 0)
187 goto out;
188 PARA_INFO_LOG("<-- [challenge] (%zu bytes)\n", n);
189 ret = priv_decrypt(ct->key_file, crypt_buf,
190 (unsigned char *)buf, n);
191 if (ret < 0)
192 goto out;
193 hash_function((char *)crypt_buf, CHALLENGE_SIZE, challenge_hash);
194 ct->scc.send = sc_new(crypt_buf + CHALLENGE_SIZE, SESSION_KEY_LEN);
195 ct->scc.recv = sc_new(crypt_buf + CHALLENGE_SIZE + SESSION_KEY_LEN,
196 SESSION_KEY_LEN);
197 hash_to_asc(challenge_hash, buf);
198 PARA_INFO_LOG("--> %s\n", buf);
199 ret = send_bin_buffer(ct->scc.fd, (char *)challenge_hash,
200 HASH_SIZE);
201 if (ret < 0)
202 goto out;
203 ct->status = CL_SENT_CH_RESPONSE;
204 return;
205 }
206 case CL_SENT_CH_RESPONSE: /* read server response */
207 {
208 ret = client_recv_buffer(ct, &s->rfds, buf, sizeof(buf), &n);
209 if (ret < 0 || n == 0)
210 goto out;
211 /* check if server has sent "Proceed" message */
212 ret = -E_CLIENT_AUTH;
213 if (n < PROCEED_MSG_LEN)
214 goto out;
215 if (!strstr(buf, PROCEED_MSG))
216 goto out;
217 ct->status = CL_RECEIVED_PROCEED;
218 return;
219 }
220 case CL_RECEIVED_PROCEED: /* concat args and send command */
221 {
222 int i;
223 char *command = NULL;
224 if (!FD_ISSET(ct->scc.fd, &s->wfds))
225 return;
226 for (i = 0; i < ct->conf.inputs_num; i++) {
227 char *tmp = command;
228 command = make_message("%s\n%s", command?
229 command : "", ct->conf.inputs[i]);
230 free(tmp);
231 }
232 command = para_strcat(command, EOC_MSG "\n");
233 PARA_DEBUG_LOG("--> %s\n", command);
234 ret = sc_send_buffer(&ct->scc, command);
235 free(command);
236 if (ret < 0)
237 goto out;
238 ct->status = CL_SENT_COMMAND;
239 return;
240 }
241 case CL_SENT_COMMAND:
242 {
243 char *buf2;
244 /* can not use "buf" here because we need a malloced buffer */
245 buf2 = para_malloc(CLIENT_BUFSIZE);
246 ret = client_recv_buffer(ct, &s->rfds, buf2, CLIENT_BUFSIZE, &n);
247 if (n > 0) {
248 if (strstr(buf2, AWAITING_DATA_MSG)) {
249 free(buf2);
250 ct->status = CL_SENDING;
251 return;
252 }
253 ct->status = CL_RECEIVING;
254 btr_add_output(buf2, n, btrn);
255 } else
256 free(buf2);
257 goto out;
258 }
259 case CL_SENDING:
260 {
261 char *buf2;
262 size_t sz;
263 ret = btr_node_status(btrn, 0, BTR_NT_LEAF);
264 if (ret < 0)
265 goto out;
266 if (ret == 0)
267 return;
268 if (!FD_ISSET(ct->scc.fd, &s->wfds))
269 return;
270 sz = btr_next_buffer(btrn, &buf2);
271 ret = sc_send_bin_buffer(&ct->scc, buf2, sz);
272 if (ret < 0)
273 goto out;
274 btr_consume(btrn, sz);
275 return;
276 }
277 case CL_RECEIVING:
278 {
279 char *buf2;
280 ret = btr_node_status(btrn, 0, BTR_NT_ROOT);
281 if (ret < 0)
282 goto out;
283 if (ret == 0)
284 return;
285 /*
286 * The FD_ISSET() is not strictly necessary, but is allows us
287 * to skip the malloc below if there is nothing to read anyway.
288 */
289 if (!FD_ISSET(ct->scc.fd, &s->rfds))
290 return;
291 buf2 = para_malloc(CLIENT_BUFSIZE);
292 ret = client_recv_buffer(ct, &s->rfds, buf2, CLIENT_BUFSIZE, &n);
293 if (n > 0) {
294 buf2 = para_realloc(buf2, n);
295 btr_add_output(buf2, n, btrn);
296 } else
297 free(buf2);
298 goto out;
299 }
300 }
301 out:
302 t->error = ret;
303 if (ret < 0) {
304 if (ret != -E_SERVER_EOF && ret != -E_BTR_EOF)
305 PARA_ERROR_LOG("%s\n", para_strerror(-t->error));
306 btr_remove_node(btrn);
307 }
308 }
309
310 /* connect to para_server and register the client task */
311 static int client_connect(struct client_task *ct)
312 {
313 int ret;
314
315 ct->scc.fd = -1;
316 ret = para_connect_simple(IPPROTO_TCP, ct->conf.hostname_arg,
317 ct->conf.server_port_arg);
318 if (ret < 0)
319 return ret;
320 ct->scc.fd = ret;
321 ct->status = CL_CONNECTED;
322 ret = mark_fd_nonblocking(ct->scc.fd);
323 if (ret < 0)
324 goto err_out;
325 ct->task.pre_select = client_pre_select;
326 ct->task.post_select = client_post_select;
327 sprintf(ct->task.status, "client");
328 register_task(&ct->task);
329 return 1;
330 err_out:
331 close(ct->scc.fd);
332 ct->scc.fd = -1;
333 return ret;
334 }
335
336 /**
337 * Open connection to para_server.
338 *
339 * \param argc Usual argument count.
340 * \param argv Usual argument vector.
341 * \param ct_ptr Points to dynamically allocated and initialized client task
342 * struct upon successful return.
343 * \param loglevel If not \p NULL, the number of the loglevel is stored here.
344 * \param parent Add the new buffer tree node as a child of this node.
345 * \param child Add the new buffer tree node as a parent of this node.
346 *
347 * Check the command line options given by \a argc and argv, set default values
348 * for user name and rsa key file, read further option from the config file.
349 * Finally, establish a connection to para_server.
350 *
351 * \return Standard.
352 */
353 int client_open(int argc, char *argv[], struct client_task **ct_ptr,
354 int *loglevel, struct btr_node *parent, struct btr_node *child)
355 {
356 char *home = para_homedir();
357 int ret;
358 struct client_task *ct = para_calloc(sizeof(struct client_task));
359
360 ct->btrn = btr_new_node(&(struct btr_node_description)
361 EMBRACE(.name = "client", .parent = parent, .child = child));
362 *ct_ptr = ct;
363 ct->scc.fd = -1;
364 ret = -E_CLIENT_SYNTAX;
365 if (client_cmdline_parser(argc, argv, &ct->conf))
366 goto out;
367 HANDLE_VERSION_FLAG("client", ct->conf);
368 ret = -E_CLIENT_SYNTAX;
369 if (!ct->conf.inputs_num)
370 goto out;
371
372 ct->config_file = ct->conf.config_file_given?
373 para_strdup(ct->conf.config_file_arg) :
374 make_message("%s/.paraslash/client.conf", home);
375 ret = file_exists(ct->config_file);
376 if (!ret && ct->conf.config_file_given) {
377 ret = -E_NO_CONFIG;
378 goto out;
379 }
380 if (ret) {
381 struct client_cmdline_parser_params params = {
382 .override = 0,
383 .initialize = 0,
384 .check_required = 0,
385 .check_ambiguity = 0,
386 .print_errors = 0
387 };
388 ret = -E_BAD_CONFIG;
389 if (client_cmdline_parser_config_file(ct->config_file,
390 &ct->conf, &params))
391 goto out;
392 }
393 ct->user = ct->conf.user_given?
394 para_strdup(ct->conf.user_arg) : para_logname();
395
396 ct->key_file = ct->conf.key_file_given?
397 para_strdup(ct->conf.key_file_arg) :
398 make_message("%s/.paraslash/key.%s", home, ct->user);
399
400 if (loglevel)
401 *loglevel = get_loglevel_by_name(ct->conf.loglevel_arg);
402 PARA_INFO_LOG("loglevel: %s\n", ct->conf.loglevel_arg);
403 PARA_INFO_LOG("config_file: %s\n", ct->config_file);
404 PARA_INFO_LOG("key_file: %s\n", ct->key_file);
405 PARA_NOTICE_LOG("connecting %s:%d\n", ct->conf.hostname_arg,
406 ct->conf.server_port_arg);
407 ret = client_connect(ct);
408 out:
409 free(home);
410 if (ret < 0) {
411 PARA_ERROR_LOG("%s\n", para_strerror(-ret));
412 btr_remove_node(ct->btrn);
413 btr_free_node(ct->btrn);
414 client_close(ct);
415 *ct_ptr = NULL;
416 }
417 return ret;
418 }