configure.ac: Fix definition of recv_ldflags.
[paraslash.git] / client_common.c
1 /*
2  * Copyright (C) 1997-2013 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 "crypt.h"
17 #include "net.h"
18 #include "fd.h"
19 #include "sideband.h"
20 #include "string.h"
21 #include "client.cmdline.h"
22 #include "client.h"
23 #include "buffer_tree.h"
24 #include "version.h"
25 #include "ggo.h"
26
27 /** The size of the receiving buffer. */
28 #define CLIENT_BUFSIZE 4000
29
30 /**
31  * Close the connection to para_server and deallocate per-command resources.
32  *
33  * \param ct The client task.
34  *
35  * This frees all resources of the current command but keeps the configuration
36  * in \p ct->conf.
37  *
38  * \sa \ref client_close().
39  */
40 void client_disconnect(struct client_task *ct)
41 {
42         if (!ct)
43                 return;
44         if (ct->scc.fd >= 0)
45                 close(ct->scc.fd);
46         free_argv(ct->features);
47         ct->features = NULL;
48         sc_free(ct->scc.recv);
49         ct->scc.recv = NULL;
50         sc_free(ct->scc.send);
51         ct->scc.send = NULL;
52         btr_remove_node(&ct->btrn);
53 }
54
55 /**
56  * Close the connection to para_server and free all resources.
57  *
58  * \param ct Pointer to the client data.
59  *
60  * \sa \ref client_open(), \ref client_disconnect().
61  */
62 void client_close(struct client_task *ct)
63 {
64         if (!ct)
65                 return;
66         client_disconnect(ct);
67         free(ct->user);
68         free(ct->config_file);
69         free(ct->key_file);
70         client_cmdline_parser_free(&ct->conf);
71         free(ct->challenge_hash);
72         sb_free(ct->sbc);
73         free(ct);
74 }
75
76 /**
77  * The preselect hook for server commands.
78  *
79  * \param s Pointer to the scheduler.
80  * \param t Pointer to the task struct for this command.
81  *
82  * The task pointer must contain a pointer to the initialized client data
83  * structure as it is returned by client_open().
84  *
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.
87  *
88  * \sa register_task() client_open(), struct sched, struct task.
89  */
90 static void client_pre_select(struct sched *s, struct task *t)
91 {
92         int ret;
93         struct client_task *ct = container_of(t, struct client_task, task);
94         struct btr_node *btrn = ct->btrn;
95
96         if (ct->scc.fd < 0)
97                 return;
98         switch (ct->status) {
99         case CL_CONNECTED:
100         case CL_SENT_AUTH:
101         case CL_SENT_CH_RESPONSE:
102         case CL_SENT_COMMAND:
103                 para_fd_set(ct->scc.fd, &s->rfds, &s->max_fileno);
104                 return;
105
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);
110                 return;
111
112         case CL_RECEIVING:
113                 ret = btr_node_status(btrn, 0, BTR_NT_ROOT);
114                 if (ret != 0) {
115                         if (ret < 0)
116                                 sched_min_delay(s);
117                         else
118                                 para_fd_set(ct->scc.fd, &s->rfds,
119                                         &s->max_fileno);
120                 }
121                 return;
122         case CL_SENDING:
123                 ret = btr_node_status(btrn, 0, BTR_NT_LEAF);
124                 if (ret != 0) {
125                         if (ret < 0)
126                                 sched_min_delay(s);
127                         else
128                                 para_fd_set(ct->scc.fd, &s->wfds,
129                                         &s->max_fileno);
130                 }
131                 return;
132         }
133 }
134
135 static int client_recv_buffer(struct client_task *ct, fd_set *rfds,
136                 char *buf, size_t sz, size_t *n)
137 {
138         int ret;
139
140         if (ct->status < CL_SENT_CH_RESPONSE)
141                 return read_nonblock(ct->scc.fd, buf, sz, rfds, n);
142
143         *n = 0;
144         ret = sc_recv_buffer(&ct->scc, buf, sz);
145         /*
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.
149          */
150         if (ret == 0)
151                 return -E_SERVER_EOF;
152         if (ret == -ERRNO_TO_PARA_ERROR(EAGAIN))
153                 return 0;
154         if (ret < 0)
155                 return ret;
156         *n = ret;
157         return 0;
158 }
159
160 static int send_sb(struct client_task *ct, void *buf, size_t numbytes,
161                 enum sb_designator band, bool dont_free)
162 {
163         int ret, fd = ct->scc.fd;
164         struct iovec iov[2];
165
166         if (!ct->sbc) {
167                 struct sb_buffer sbb;
168                 sb_transformation trafo = ct->status < CL_RECEIVED_PROCEED?
169                         NULL : sc_trafo;
170                 sbb = (typeof(sbb))SBB_INIT(band, buf, numbytes);
171                 ct->sbc = sb_new_send(&sbb, dont_free, trafo, ct->scc.send);
172         }
173         ret = sb_get_send_buffers(ct->sbc, iov);
174         ret = xwritev(fd, iov, ret);
175         if (ret < 0) {
176                 sb_free(ct->sbc);
177                 ct->sbc = NULL;
178                 return ret;
179         }
180         if (sb_sent(ct->sbc, ret)) {
181                 ct->sbc = NULL;
182                 return 1;
183         }
184         return 0;
185 }
186
187 static int recv_sb(struct client_task *ct, fd_set *rfds,
188                 struct sb_buffer *result)
189 {
190         int ret;
191         size_t n;
192         sb_transformation trafo;
193         void *trafo_context;
194         struct iovec iov;
195
196         if (!FD_ISSET(ct->scc.fd, rfds))
197                 return 0;
198         if (ct->status < CL_SENT_CH_RESPONSE)
199                 trafo = trafo_context = NULL;
200         else {
201                 trafo = sc_trafo;
202                 trafo_context = ct->scc.recv;
203         }
204         if (!ct->sbc)
205                 ct->sbc = sb_new_recv(0, trafo, trafo_context);
206 again:
207         sb_get_recv_buffer(ct->sbc, &iov);
208         ret = read_nonblock(ct->scc.fd, iov.iov_base, iov.iov_len, rfds, &n);
209         if (ret < 0) {
210                 sb_free(ct->sbc);
211                 ct->sbc = NULL;
212                 return ret;
213         }
214         if (n == 0)
215                 return 0;
216         if (!sb_received(ct->sbc, n, result))
217                 goto again;
218         ct->sbc = NULL;
219         return 1;
220 }
221
222
223 static char **parse_features(char *buf)
224 {
225         int i;
226         const char id[] = "\nFeatures: ";
227         char *p, *q, **features;
228
229         p = strstr(buf, id);
230         if (!p)
231                 return NULL;
232         p += strlen(id);
233         q = strchr(p, '\n');
234         if (!q)
235                 return NULL;
236         *q = '\0';
237         create_argv(p, ",", &features);
238         for (i = 0; features[i]; i++)
239                 PARA_INFO_LOG("server feature: %s\n", features[i]);
240         return features;
241 }
242
243 static int dispatch_sbb(struct client_task *ct, struct sb_buffer *sbb)
244 {
245         int ret;
246         const char *designator[] = {SB_DESIGNATORS_ARRAY};
247
248         if (!sbb)
249                 return 0;
250         if (sbb->band < NUM_SB_DESIGNATORS)
251                 PARA_DEBUG_LOG("band: %s\n", designator[sbb->band]);
252
253         switch (sbb->band) {
254         case SBD_OUTPUT:
255                 if (iov_valid(&sbb->iov))
256                         btr_add_output(sbb->iov.iov_base, sbb->iov.iov_len,
257                                 ct->btrn);
258                 ret = 1;
259                 goto out;
260         case SBD_DEBUG_LOG:
261         case SBD_INFO_LOG:
262         case SBD_NOTICE_LOG:
263         case SBD_WARNING_LOG:
264         case SBD_ERROR_LOG:
265         case SBD_CRIT_LOG:
266         case SBD_EMERG_LOG:
267                 if (iov_valid(&sbb->iov)) {
268                         int ll = sbb->band - SBD_DEBUG_LOG;
269                         para_log(ll, "remote: %s", (char *)sbb->iov.iov_base);
270                 }
271                 ret = 1;
272                 goto deallocate;
273         case SBD_EXIT__SUCCESS:
274                 ret = -E_SERVER_CMD_SUCCESS;
275                 goto deallocate;
276         case SBD_EXIT__FAILURE:
277                 ret = -E_SERVER_CMD_FAILURE;
278                 goto deallocate;
279         default:
280                 PARA_ERROR_LOG("invalid band %d\n", sbb->band);
281                 ret = -E_BAD_BAND;
282                 goto deallocate;
283         }
284 deallocate:
285         free(sbb->iov.iov_base);
286 out:
287         sbb->iov.iov_base = NULL;
288         return ret;
289 }
290
291 static bool has_feature(const char *feature, struct client_task *ct)
292 {
293         return find_arg(feature, ct->features) >= 0? true : false;
294 }
295
296 static int send_sb_command(struct client_task *ct)
297 {
298         int i;
299         char *command, *p;
300         size_t len = 0;
301
302         if (ct->sbc)
303                 return send_sb(ct, NULL, 0, 0, false);
304
305         for (i = 0; i < ct->conf.inputs_num; i++)
306                 len += strlen(ct->conf.inputs[i]) + 1;
307         p = command = para_malloc(len);
308         for (i = 0; i < ct->conf.inputs_num; i++) {
309                 strcpy(p, ct->conf.inputs[i]);
310                 p += strlen(ct->conf.inputs[i]) + 1;
311         }
312         PARA_DEBUG_LOG("--> %s\n", command);
313         return send_sb(ct, command, len, SBD_COMMAND, false);
314 }
315
316 /**
317  * The post select hook for client commands.
318  *
319  * \param s Pointer to the scheduler.
320  * \param t Pointer to the task struct for this command.
321  *
322  * Depending on the current state of the connection and the status of the read
323  * and write fd sets of \a s, this function performs the necessary steps to
324  * authenticate the connection, to send the command given by \a t->private_data
325  * and to receive para_server's output, if any.
326  *
327  * \sa struct sched, struct task.
328  */
329 static int client_post_select(struct sched *s, struct task *t)
330 {
331         struct client_task *ct = container_of(t, struct client_task, task);
332         struct btr_node *btrn = ct->btrn;
333         int ret = 0;
334         size_t n;
335         char buf[CLIENT_BUFSIZE];
336
337         ret = task_get_notification(t);
338         if (ret < 0)
339                 goto out;
340         if (ct->scc.fd < 0)
341                 return 0;
342         switch (ct->status) {
343         case CL_CONNECTED: /* receive welcome message */
344                 ret = client_recv_buffer(ct, &s->rfds, buf, sizeof(buf), &n);
345                 if (ret < 0 || n == 0)
346                         goto out;
347                 ct->features = parse_features(buf);
348                 ct->status = CL_RECEIVED_WELCOME;
349                 return 0;
350         case CL_RECEIVED_WELCOME: /* send auth command */
351                 if (!FD_ISSET(ct->scc.fd, &s->wfds))
352                         return 0;
353                 if (has_feature("sideband", ct)) {
354                         ct->use_sideband = true;
355                         sprintf(buf, AUTH_REQUEST_MSG "%s sideband", ct->user);
356                 } else
357                         sprintf(buf, AUTH_REQUEST_MSG "%s", ct->user);
358                 PARA_INFO_LOG("--> %s\n", buf);
359                 ret = write_buffer(ct->scc.fd, buf);
360                 if (ret < 0)
361                         goto out;
362                 ct->status = CL_SENT_AUTH;
363                 return 0;
364         case CL_SENT_AUTH:
365                 /*
366                  * Receive challenge and session keys, decrypt the challenge and
367                  * send back the hash of the decrypted challenge.
368                  */
369                 {
370                 /* decrypted challenge/session key buffer */
371                 unsigned char crypt_buf[1024];
372                 /* the SHA1 of the decrypted challenge */
373
374                 if (ct->use_sideband) {
375                         struct sb_buffer sbb;
376                         ret = recv_sb(ct, &s->rfds, &sbb);
377                         if (ret <= 0)
378                                 goto out;
379                         if (sbb.band != SBD_CHALLENGE) {
380                                 ret = -E_BAD_BAND;
381                                 free(sbb.iov.iov_base);
382                                         goto out;
383                         }
384                         n = sbb.iov.iov_len;
385                         PARA_INFO_LOG("<-- [challenge] (%zu bytes)\n", n);
386                         ret = priv_decrypt(ct->key_file, crypt_buf,
387                                 sbb.iov.iov_base, n);
388                         free(sbb.iov.iov_base);
389                         if (ret < 0)
390                                 goto out;
391                 } else {
392                         ret = client_recv_buffer(ct, &s->rfds, buf, sizeof(buf), &n);
393                         if (ret < 0 || n == 0)
394                                 goto out;
395                         PARA_INFO_LOG("<-- [challenge] (%zu bytes)\n", n);
396                         ret = priv_decrypt(ct->key_file, crypt_buf,
397                                 (unsigned char *)buf, n);
398                         if (ret < 0)
399                                 goto out;
400                 }
401                 ct->challenge_hash = para_malloc(HASH_SIZE);
402                 hash_function((char *)crypt_buf, CHALLENGE_SIZE, ct->challenge_hash);
403                 ct->scc.send = sc_new(crypt_buf + CHALLENGE_SIZE, SESSION_KEY_LEN);
404                 ct->scc.recv = sc_new(crypt_buf + CHALLENGE_SIZE + SESSION_KEY_LEN,
405                         SESSION_KEY_LEN);
406                 hash_to_asc(ct->challenge_hash, buf);
407                 PARA_INFO_LOG("--> %s\n", buf);
408                 ct->status = CL_RECEIVED_CHALLENGE;
409                 return 0;
410                 }
411         case CL_RECEIVED_CHALLENGE:
412                 if (ct->use_sideband) {
413                         ret = send_sb(ct, ct->challenge_hash, HASH_SIZE,
414                                 SBD_CHALLENGE_RESPONSE, false);
415                         if (ret != 0)
416                                 ct->challenge_hash = NULL;
417                         if (ret <= 0)
418                                 goto out;
419                 } else {
420                         ret = write_all(ct->scc.fd, (char *)ct->challenge_hash, HASH_SIZE);
421                         if (ret < 0)
422                                 goto out;
423                 }
424                 ct->status = CL_SENT_CH_RESPONSE;
425                 goto out;
426         case CL_SENT_CH_RESPONSE: /* read server response */
427                 {
428                 if (ct->use_sideband) {
429                         struct sb_buffer sbb;
430                         ret = recv_sb(ct, &s->rfds, &sbb);
431                         if (ret <= 0)
432                                 goto out;
433                         free(sbb.iov.iov_base);
434                         if (sbb.band != SBD_PROCEED)
435                                 ret = -E_BAD_BAND;
436                         else
437                                 ct->status = CL_RECEIVED_PROCEED;
438                         goto out;
439                 }
440                 ret = client_recv_buffer(ct, &s->rfds, buf, sizeof(buf), &n);
441                 if (ret < 0 || n == 0)
442                         goto out;
443                 /* check if server has sent "Proceed" message */
444                 ret = -E_CLIENT_AUTH;
445                 if (n < PROCEED_MSG_LEN)
446                         goto out;
447                 if (!strstr(buf, PROCEED_MSG))
448                         goto out;
449                 ct->status = CL_RECEIVED_PROCEED;
450                 return 0;
451                 }
452         case CL_RECEIVED_PROCEED: /* concat args and send command */
453                 {
454                 int i;
455                 char *command = NULL;
456                 if (!FD_ISSET(ct->scc.fd, &s->wfds))
457                         return 0;
458                 if (ct->use_sideband) {
459                         ret = send_sb_command(ct);
460                         if (ret <= 0)
461                                 goto out;
462                         ct->status = CL_SENT_COMMAND;
463                         return 0;
464                 }
465                 for (i = 0; i < ct->conf.inputs_num; i++) {
466                         char *tmp = command;
467                         command = make_message("%s\n%s", command?
468                                 command : "", ct->conf.inputs[i]);
469                         free(tmp);
470                 }
471                 command = para_strcat(command, EOC_MSG "\n");
472                 PARA_DEBUG_LOG("--> %s\n", command);
473                 ret = sc_send_buffer(&ct->scc, command);
474                 free(command);
475                 if (ret < 0)
476                         goto out;
477                 ct->status = CL_SENT_COMMAND;
478                 return 0;
479                 }
480         case CL_SENT_COMMAND:
481                 {
482                 char *buf2;
483                 if (ct->use_sideband) {
484                         struct sb_buffer sbb;
485                         ret = recv_sb(ct, &s->rfds, &sbb);
486                         if (ret <= 0)
487                                 goto out;
488                         if (sbb.band == SBD_AWAITING_DATA) {
489                                 ct->status = CL_SENDING;
490                                 free(sbb.iov.iov_base);
491                                 goto out;
492                         }
493                         ct->status = CL_RECEIVING;
494                         ret = dispatch_sbb(ct, &sbb);
495                         goto out;
496                 }
497                 /* can not use "buf" here because we need a malloced buffer */
498                 buf2 = para_malloc(CLIENT_BUFSIZE);
499                 ret = client_recv_buffer(ct, &s->rfds, buf2, CLIENT_BUFSIZE, &n);
500                 if (n > 0) {
501                         if (strstr(buf2, AWAITING_DATA_MSG)) {
502                                 free(buf2);
503                                 ct->status = CL_SENDING;
504                                 return 0;
505                         }
506                         ct->status = CL_RECEIVING;
507                         btr_add_output(buf2, n, btrn);
508                 } else
509                         free(buf2);
510                 goto out;
511                 }
512         case CL_SENDING:
513                 {
514                 char *buf2;
515                 size_t sz;
516                 ret = btr_node_status(btrn, 0, BTR_NT_LEAF);
517                 if (ret < 0)
518                         goto out;
519                 if (ret == 0)
520                         return 0;
521                 if (!FD_ISSET(ct->scc.fd, &s->wfds))
522                         return 0;
523                 sz = btr_next_buffer(btrn, &buf2);
524                 ret = sc_send_bin_buffer(&ct->scc, buf2, sz);
525                 if (ret < 0)
526                         goto out;
527                 btr_consume(btrn, sz);
528                 return 0;
529                 }
530         case CL_RECEIVING:
531                 {
532                 char *buf2;
533                 ret = btr_node_status(btrn, 0, BTR_NT_ROOT);
534                 if (ret < 0)
535                         goto out;
536                 if (ret == 0)
537                         return 0;
538                 /*
539                  * The FD_ISSET() is not strictly necessary, but is allows us
540                  * to skip the malloc below if there is nothing to read anyway.
541                  */
542                 if (!FD_ISSET(ct->scc.fd, &s->rfds))
543                         return 0;
544                 if (ct->use_sideband) {
545                         struct sb_buffer sbb;
546                         ret = recv_sb(ct, &s->rfds, &sbb);
547                         if (ret > 0)
548                                 ret = dispatch_sbb(ct, &sbb);
549                         goto out;
550                 }
551                 buf2 = para_malloc(CLIENT_BUFSIZE);
552                 ret = client_recv_buffer(ct, &s->rfds, buf2, CLIENT_BUFSIZE, &n);
553                 if (n > 0) {
554                         buf2 = para_realloc(buf2, n);
555                         btr_add_output(buf2, n, btrn);
556                 } else
557                         free(buf2);
558                 goto out;
559                 }
560         }
561 out:
562         if (ret < 0) {
563                 if (!ct->use_sideband && ret != -E_SERVER_EOF &&
564                                 ret != -E_BTR_EOF && ret != -E_EOF)
565                         PARA_ERROR_LOG("%s\n", para_strerror(-ret));
566                 btr_remove_node(&ct->btrn);
567         }
568         return ret;
569 }
570
571 /**
572  * Connect to para_server and register the client task.
573  *
574  * \param ct The initialized client task structure.
575  * \param s The scheduler instance to register the client task to.
576  * \param parent The parent node of the client btr node.
577  * \param child The child node of the client node.
578  *
579  * The client task structure given by \a ct  must be allocated and initialized
580  * by \ref client_parse_config() before this function is called.
581  *
582  * \return Standard.
583  */
584 int client_connect(struct client_task *ct, struct sched *s,
585                 struct btr_node *parent, struct btr_node *child)
586 {
587         int ret;
588
589         PARA_NOTICE_LOG("connecting %s:%d\n", ct->conf.hostname_arg,
590                 ct->conf.server_port_arg);
591         ct->scc.fd = -1;
592         ret = para_connect_simple(IPPROTO_TCP, ct->conf.hostname_arg,
593                                                ct->conf.server_port_arg);
594         if (ret < 0)
595                 return ret;
596         ct->scc.fd = ret;
597         ret = mark_fd_nonblocking(ct->scc.fd);
598         if (ret < 0)
599                 goto err_out;
600         ct->status = CL_CONNECTED;
601         ct->btrn = btr_new_node(&(struct btr_node_description)
602                 EMBRACE(.name = "client", .parent = parent, .child = child));
603         ct->task.pre_select = client_pre_select;
604         ct->task.post_select = client_post_select;
605         ct->task.error = 0;
606         sprintf(ct->task.status, "client");
607         register_task(s, &ct->task);
608         return 1;
609 err_out:
610         close(ct->scc.fd);
611         ct->scc.fd = -1;
612         return ret;
613 }
614
615 __noreturn static void print_help_and_die(struct client_task *ct)
616 {
617         struct ggo_help h = DEFINE_GGO_HELP(client);
618         bool d = ct->conf.detailed_help_given;
619
620         ggo_print_help(&h, d? GPH_STANDARD_FLAGS_DETAILED : GPH_STANDARD_FLAGS);
621         exit(0);
622 }
623
624 /**
625  * Parse a client configuration.
626  *
627  * \param argc Usual argument count.
628  * \param argv Usual argument vector.
629  * \param ct_ptr Filled in by this function.
630  * \param loglevel If not \p NULL, the number of the loglevel is stored here.
631  *
632  * This checks the command line options given by \a argc and \a argv, sets
633  * default values for the user name and the name of the rsa key file and reads
634  * further options from the config file.
635  *
636  * Upon successful return, \a ct_ptr points to a dynamically allocated and
637  * initialized client task struct.
638  *
639  * \return The number of non-option arguments in \a argc/argv on success,
640  * negative on errors.
641  */
642 int client_parse_config(int argc, char *argv[], struct client_task **ct_ptr,
643                 int *loglevel)
644 {
645         char *home = para_homedir();
646         int ret;
647         struct client_task *ct = para_calloc(sizeof(struct client_task));
648
649         *ct_ptr = ct;
650         ct->scc.fd = -1;
651         ret = -E_CLIENT_SYNTAX;
652         if (client_cmdline_parser(argc, argv, &ct->conf))
653                 goto out;
654         version_handle_flag("client", ct->conf.version_given);
655         if (ct->conf.help_given || ct->conf.detailed_help_given)
656                 print_help_and_die(ct);
657
658         ct->config_file = ct->conf.config_file_given?
659                 para_strdup(ct->conf.config_file_arg) :
660                 make_message("%s/.paraslash/client.conf", home);
661         ret = file_exists(ct->config_file);
662         if (!ret && ct->conf.config_file_given) {
663                 ret = -E_NO_CONFIG;
664                 goto out;
665         }
666         if (ret) {
667                 struct client_cmdline_parser_params params = {
668                         .override = 0,
669                         .initialize = 0,
670                         .check_required = 0,
671                         .check_ambiguity = 0,
672                         .print_errors = 0
673                 };
674                 ret = -E_BAD_CONFIG;
675                 if (client_cmdline_parser_config_file(ct->config_file,
676                         &ct->conf, &params))
677                         goto out;
678         }
679         ct->user = ct->conf.user_given?
680                 para_strdup(ct->conf.user_arg) : para_logname();
681
682         if (ct->conf.key_file_given)
683                 ct->key_file = para_strdup(ct->conf.key_file_arg);
684         else {
685                 ct->key_file = make_message("%s/.paraslash/key.%s",
686                         home, ct->user);
687                 if (!file_exists(ct->key_file)) {
688                         free(ct->key_file);
689                         ct->key_file = make_message("%s/.ssh/id_rsa", home);
690                 }
691         }
692
693         if (loglevel)
694                 *loglevel = get_loglevel_by_name(ct->conf.loglevel_arg);
695         PARA_INFO_LOG("loglevel: %s\n", ct->conf.loglevel_arg);
696         PARA_INFO_LOG("config_file: %s\n", ct->config_file);
697         PARA_INFO_LOG("key_file: %s\n", ct->key_file);
698         ret = ct->conf.inputs_num;
699 out:
700         free(home);
701         if (ret < 0) {
702                 PARA_ERROR_LOG("%s\n", para_strerror(-ret));
703                 client_close(ct);
704                 *ct_ptr = NULL;
705         }
706         return ret;
707 }
708
709 /**
710  * Parse the client configuration and open a connection to para_server.
711  *
712  * \param argc See \ref client_parse_config.
713  * \param argv See \ref client_parse_config.
714  * \param ct_ptr See \ref client_parse_config.
715  * \param loglevel See \ref client_parse_config.
716  * \param parent See \ref client_connect().
717  * \param child See \ref client_connect().
718  * \param sched See \ref client_connect().
719  *
720  * This function combines client_parse_config() and client_connect(). It is
721  * considered a syntax error if no command was given, i.e. if the number
722  * of non-option arguments is zero.
723  *
724  * \return Standard.
725  */
726 int client_open(int argc, char *argv[], struct client_task **ct_ptr,
727                 int *loglevel, struct btr_node *parent, struct btr_node *child,
728                 struct sched *sched)
729 {
730         int ret = client_parse_config(argc, argv, ct_ptr, loglevel);
731
732         if (ret < 0)
733                 return ret;
734         if (ret == 0) {
735                 ret = -E_CLIENT_SYNTAX;
736                 goto fail;
737         }
738         ret = client_connect(*ct_ptr, sched, parent, child);
739         if (ret < 0)
740                 goto fail;
741         return 1;
742 fail:
743         client_close(*ct_ptr);
744         *ct_ptr = NULL;
745         return ret;
746 }