2 * Copyright (C) 1997-2012 Andre Noll <maan@systemlinux.org>
4 * Licensed under the GPL v2. For licencing details see COPYING.
7 /** \file client_common.c Common functions of para_client and para_audiod. */
10 #include <sys/types.h>
16 #include "client.cmdline.h"
22 #include "client.cmdline.h"
24 #include "buffer_tree.h"
27 /** The size of the receiving buffer. */
28 #define CLIENT_BUFSIZE 4000
31 * Close the connection to para_server and deallocate per-command ressources.
33 * \param ct The client task.
35 * This frees all ressources of the current command but keeps the configuration
38 * \sa \ref client_close().
40 void client_disconnect(struct client_task *ct)
46 free_argv(ct->features);
47 sc_free(ct->scc.recv);
49 sc_free(ct->scc.send);
51 btr_free_node(ct->btrn);
56 * Close the connection to para_server and free all resources.
58 * \param ct Pointer to the client data.
60 * \sa \ref client_open(), \ref client_disconnect().
62 void client_close(struct client_task *ct)
66 client_disconnect(ct);
68 free(ct->config_file);
70 client_cmdline_parser_free(&ct->conf);
71 free(ct->challenge_hash);
77 * The preselect hook for server commands.
79 * \param s Pointer to the scheduler.
80 * \param t Pointer to the task struct for this command.
82 * The task pointer must contain a pointer to the initialized client data
83 * structure as it is returned by client_open().
85 * This function checks the state of the connection and adds the file descriptor
86 * of the connection to the read or write fd set of \a s accordingly.
88 * \sa register_task() client_open(), struct sched, struct task.
90 static void client_pre_select(struct sched *s, struct task *t)
93 struct client_task *ct = container_of(t, struct client_task, task);
94 struct btr_node *btrn = ct->btrn;
101 case CL_SENT_CH_RESPONSE:
102 case CL_SENT_COMMAND:
103 para_fd_set(ct->scc.fd, &s->rfds, &s->max_fileno);
106 case CL_RECEIVED_WELCOME:
107 case CL_RECEIVED_PROCEED:
108 case CL_RECEIVED_CHALLENGE:
109 para_fd_set(ct->scc.fd, &s->wfds, &s->max_fileno);
113 ret = btr_node_status(btrn, 0, BTR_NT_ROOT);
118 para_fd_set(ct->scc.fd, &s->rfds,
123 ret = btr_node_status(btrn, 0, BTR_NT_LEAF);
128 para_fd_set(ct->scc.fd, &s->wfds,
135 static int client_recv_buffer(struct client_task *ct, fd_set *rfds,
136 char *buf, size_t sz, size_t *n)
140 if (ct->status < CL_SENT_CH_RESPONSE)
141 return read_nonblock(ct->scc.fd, buf, sz, rfds, n);
144 ret = sc_recv_buffer(&ct->scc, buf, sz);
146 * sc_recv_buffer is used with blocking fds elsewhere, so it
147 * does not use the nonblock-API. Therefore we need to
148 * check for EOF and EAGAIN.
151 return -E_SERVER_EOF;
152 if (ret == -ERRNO_TO_PARA_ERROR(EAGAIN))
160 static int send_sb(struct client_task *ct, void *buf, size_t numbytes,
161 enum sb_designator band, bool dont_free)
163 int ret, fd = ct->scc.fd;
167 struct sb_buffer sbb;
168 sb_transformation trafo = ct->status < CL_RECEIVED_PROCEED?
170 sbb = (typeof(sbb))SBB_INIT(band, buf, numbytes);
171 ct->sbc = sb_new_send(&sbb, dont_free, trafo, ct->scc.send);
173 ret = sb_get_send_buffers(ct->sbc, iov);
174 ret = xwritev(fd, iov, ret);
180 if (sb_sent(ct->sbc, ret)) {
187 static int recv_sb(struct client_task *ct, fd_set *rfds,
188 struct sb_buffer *result)
192 sb_transformation trafo;
196 if (!FD_ISSET(ct->scc.fd, rfds))
198 if (ct->status < CL_SENT_CH_RESPONSE)
199 trafo = trafo_context = NULL;
202 trafo_context = ct->scc.recv;
205 ct->sbc = sb_new_recv(0, trafo, trafo_context);
207 sb_get_recv_buffer(ct->sbc, &iov);
208 ret = read_nonblock(ct->scc.fd, iov.iov_base, iov.iov_len, rfds, &n);
216 if (!sb_received(ct->sbc, n, result))
223 static char **parse_features(char *buf)
226 const char id[] = "\nFeatures: ";
227 char *p, *q, **features;
237 create_argv(p, ",", &features);
238 for (i = 0; features[i]; i++)
239 PARA_INFO_LOG("server feature: %s\n", features[i]);
243 static bool has_feature(const char *feature, struct client_task *ct)
245 return find_arg(feature, ct->features) >= 0? true : false;
249 * The post select hook for client commands.
251 * \param s Pointer to the scheduler.
252 * \param t Pointer to the task struct for this command.
254 * Depending on the current state of the connection and the status of the read
255 * and write fd sets of \a s, this function performs the necessary steps to
256 * authenticate the connection, to send the command given by \a t->private_data
257 * and to receive para_server's output, if any.
259 * \sa struct sched, struct task.
261 static void client_post_select(struct sched *s, struct task *t)
263 struct client_task *ct = container_of(t, struct client_task, task);
264 struct btr_node *btrn = ct->btrn;
267 char buf[CLIENT_BUFSIZE];
272 switch (ct->status) {
273 case CL_CONNECTED: /* receive welcome message */
274 ret = client_recv_buffer(ct, &s->rfds, buf, sizeof(buf), &n);
275 if (ret < 0 || n == 0)
277 ct->features = parse_features(buf);
278 ct->status = CL_RECEIVED_WELCOME;
280 case CL_RECEIVED_WELCOME: /* send auth command */
281 if (!FD_ISSET(ct->scc.fd, &s->wfds))
283 if (has_feature("sideband", ct)) {
284 ct->use_sideband = true;
285 sprintf(buf, AUTH_REQUEST_MSG "%s sideband", ct->user);
287 sprintf(buf, AUTH_REQUEST_MSG "%s", ct->user);
288 PARA_INFO_LOG("--> %s\n", buf);
289 ret = write_buffer(ct->scc.fd, buf);
292 ct->status = CL_SENT_AUTH;
296 * Receive challenge and session keys, decrypt the challenge and
297 * send back the hash of the decrypted challenge.
300 /* decrypted challenge/session key buffer */
301 unsigned char crypt_buf[1024];
302 /* the SHA1 of the decrypted challenge */
304 if (ct->use_sideband) {
305 struct sb_buffer sbb;
306 ret = recv_sb(ct, &s->rfds, &sbb);
309 if (sbb.band != SBD_CHALLENGE) {
311 free(sbb.iov.iov_base);
315 PARA_INFO_LOG("<-- [challenge] (%zu bytes)\n", n);
316 ret = priv_decrypt(ct->key_file, crypt_buf,
317 sbb.iov.iov_base, n);
318 free(sbb.iov.iov_base);
322 ret = client_recv_buffer(ct, &s->rfds, buf, sizeof(buf), &n);
323 if (ret < 0 || n == 0)
325 PARA_INFO_LOG("<-- [challenge] (%zu bytes)\n", n);
326 ret = priv_decrypt(ct->key_file, crypt_buf,
327 (unsigned char *)buf, n);
331 ct->challenge_hash = para_malloc(HASH_SIZE);
332 hash_function((char *)crypt_buf, CHALLENGE_SIZE, ct->challenge_hash);
333 ct->scc.send = sc_new(crypt_buf + CHALLENGE_SIZE, SESSION_KEY_LEN);
334 ct->scc.recv = sc_new(crypt_buf + CHALLENGE_SIZE + SESSION_KEY_LEN,
336 hash_to_asc(ct->challenge_hash, buf);
337 PARA_INFO_LOG("--> %s\n", buf);
338 ct->status = CL_RECEIVED_CHALLENGE;
341 case CL_RECEIVED_CHALLENGE:
342 if (ct->use_sideband) {
343 ret = send_sb(ct, ct->challenge_hash, HASH_SIZE,
344 SBD_CHALLENGE_RESPONSE, false);
346 ct->challenge_hash = NULL;
350 ret = write_all(ct->scc.fd, (char *)ct->challenge_hash, HASH_SIZE);
354 ct->status = CL_SENT_CH_RESPONSE;
356 case CL_SENT_CH_RESPONSE: /* read server response */
358 ret = client_recv_buffer(ct, &s->rfds, buf, sizeof(buf), &n);
359 if (ret < 0 || n == 0)
361 /* check if server has sent "Proceed" message */
362 ret = -E_CLIENT_AUTH;
363 if (n < PROCEED_MSG_LEN)
365 if (!strstr(buf, PROCEED_MSG))
367 ct->status = CL_RECEIVED_PROCEED;
370 case CL_RECEIVED_PROCEED: /* concat args and send command */
373 char *command = NULL;
374 if (!FD_ISSET(ct->scc.fd, &s->wfds))
376 for (i = 0; i < ct->conf.inputs_num; i++) {
378 command = make_message("%s\n%s", command?
379 command : "", ct->conf.inputs[i]);
382 command = para_strcat(command, EOC_MSG "\n");
383 PARA_DEBUG_LOG("--> %s\n", command);
384 ret = sc_send_buffer(&ct->scc, command);
388 ct->status = CL_SENT_COMMAND;
391 case CL_SENT_COMMAND:
394 /* can not use "buf" here because we need a malloced buffer */
395 buf2 = para_malloc(CLIENT_BUFSIZE);
396 ret = client_recv_buffer(ct, &s->rfds, buf2, CLIENT_BUFSIZE, &n);
398 if (strstr(buf2, AWAITING_DATA_MSG)) {
400 ct->status = CL_SENDING;
403 ct->status = CL_RECEIVING;
404 btr_add_output(buf2, n, btrn);
413 ret = btr_node_status(btrn, 0, BTR_NT_LEAF);
418 if (!FD_ISSET(ct->scc.fd, &s->wfds))
420 sz = btr_next_buffer(btrn, &buf2);
421 ret = sc_send_bin_buffer(&ct->scc, buf2, sz);
424 btr_consume(btrn, sz);
430 ret = btr_node_status(btrn, 0, BTR_NT_ROOT);
436 * The FD_ISSET() is not strictly necessary, but is allows us
437 * to skip the malloc below if there is nothing to read anyway.
439 if (!FD_ISSET(ct->scc.fd, &s->rfds))
441 buf2 = para_malloc(CLIENT_BUFSIZE);
442 ret = client_recv_buffer(ct, &s->rfds, buf2, CLIENT_BUFSIZE, &n);
444 buf2 = para_realloc(buf2, n);
445 btr_add_output(buf2, n, btrn);
454 if (ret != -E_SERVER_EOF && ret != -E_BTR_EOF && ret != -E_EOF)
455 PARA_ERROR_LOG("%s\n", para_strerror(-t->error));
456 btr_remove_node(btrn);
461 * Connect to para_server and register the client task.
463 * \param ct The initialized client task structure.
464 * \param s The scheduler instance to register the client task to.
465 * \param parent The parent node of the client btr node.
466 * \param child The child node of the client node.
468 * The client task structure given by \a ct must be allocated and initialized
469 * by \ref client_parse_config() before this function is called.
473 int client_connect(struct client_task *ct, struct sched *s,
474 struct btr_node *parent, struct btr_node *child)
478 PARA_NOTICE_LOG("connecting %s:%d\n", ct->conf.hostname_arg,
479 ct->conf.server_port_arg);
481 ret = para_connect_simple(IPPROTO_TCP, ct->conf.hostname_arg,
482 ct->conf.server_port_arg);
486 ret = mark_fd_nonblocking(ct->scc.fd);
489 ct->status = CL_CONNECTED;
490 ct->btrn = btr_new_node(&(struct btr_node_description)
491 EMBRACE(.name = "client", .parent = parent, .child = child));
492 ct->task.pre_select = client_pre_select;
493 ct->task.post_select = client_post_select;
495 sprintf(ct->task.status, "client");
496 register_task(s, &ct->task);
505 * Parse a client configuration.
507 * \param argc Usual argument count.
508 * \param argv Usual argument vector.
509 * \param ct_ptr Filled in by this function.
510 * \param loglevel If not \p NULL, the number of the loglevel is stored here.
512 * This checks the command line options given by \a argc and \a argv, sets
513 * default values for the user name and the name of the rsa key file and reads
514 * further options from the config file.
516 * Upon successful return, \a ct_ptr points to a dynamically allocated and
517 * initialized client task struct.
519 * \return The number of non-option arguments in \a argc/argv on success,
520 * negative on errors.
522 int client_parse_config(int argc, char *argv[], struct client_task **ct_ptr,
525 char *home = para_homedir();
527 struct client_task *ct = para_calloc(sizeof(struct client_task));
531 ret = -E_CLIENT_SYNTAX;
532 if (client_cmdline_parser(argc, argv, &ct->conf))
534 HANDLE_VERSION_FLAG("client", ct->conf);
536 ct->config_file = ct->conf.config_file_given?
537 para_strdup(ct->conf.config_file_arg) :
538 make_message("%s/.paraslash/client.conf", home);
539 ret = file_exists(ct->config_file);
540 if (!ret && ct->conf.config_file_given) {
545 struct client_cmdline_parser_params params = {
549 .check_ambiguity = 0,
553 if (client_cmdline_parser_config_file(ct->config_file,
557 ct->user = ct->conf.user_given?
558 para_strdup(ct->conf.user_arg) : para_logname();
560 if (ct->conf.key_file_given)
561 ct->key_file = para_strdup(ct->conf.key_file_arg);
563 ct->key_file = make_message("%s/.paraslash/key.%s",
565 if (!file_exists(ct->key_file)) {
567 ct->key_file = make_message("%s/.ssh/id_rsa", home);
572 *loglevel = get_loglevel_by_name(ct->conf.loglevel_arg);
573 PARA_INFO_LOG("loglevel: %s\n", ct->conf.loglevel_arg);
574 PARA_INFO_LOG("config_file: %s\n", ct->config_file);
575 PARA_INFO_LOG("key_file: %s\n", ct->key_file);
576 ret = ct->conf.inputs_num;
580 PARA_ERROR_LOG("%s\n", para_strerror(-ret));
588 * Parse the client configuration and open a connection to para_server.
590 * \param argc See \ref client_parse_config.
591 * \param argv See \ref client_parse_config.
592 * \param ct_ptr See \ref client_parse_config.
593 * \param loglevel See \ref client_parse_config.
594 * \param parent See \ref client_connect().
595 * \param child See \ref client_connect().
596 * \param sched See \ref client_connect().
598 * This function combines client_parse_config() and client_connect(). It is
599 * considered a syntax error if no command was given, i.e. if the number
600 * of non-option arguments is zero.
604 int client_open(int argc, char *argv[], struct client_task **ct_ptr,
605 int *loglevel, struct btr_node *parent, struct btr_node *child,
608 int ret = client_parse_config(argc, argv, ct_ptr, loglevel);
613 ret = -E_CLIENT_SYNTAX;
616 ret = client_connect(*ct_ptr, sched, parent, child);
621 client_close(*ct_ptr);