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 "client.cmdline.h"
  17 #include "crypt.h"
  18 #include "net.h"
  19 #include "fd.h"
  20 #include "sideband.h"
  21 #include "string.h"
  22 #include "client.cmdline.h"
  23 #include "client.h"
  24 #include "buffer_tree.h"
  25 #include "version.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 ressources.
  32  *
  33  * \param ct The client task.
  34  *
  35  * This frees all ressources 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.new_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 /**
 616  * Parse a client configuration.
 617  *
 618  * \param argc Usual argument count.
 619  * \param argv Usual argument vector.
 620  * \param ct_ptr Filled in by this function.
 621  * \param loglevel If not \p NULL, the number of the loglevel is stored here.
 622  *
 623  * This checks the command line options given by \a argc and \a argv, sets
 624  * default values for the user name and the name of the rsa key file and reads
 625  * further options from the config file.
 626  *
 627  * Upon successful return, \a ct_ptr points to a dynamically allocated and
 628  * initialized client task struct.
 629  *
 630  * \return The number of non-option arguments in \a argc/argv on success,
 631  * negative on errors.
 632  */
 633 int client_parse_config(int argc, char *argv[], struct client_task **ct_ptr,
 634                 int *loglevel)
 635 {
 636         char *home = para_homedir();
 637         int ret;
 638         struct client_task *ct = para_calloc(sizeof(struct client_task));
 639
 640         *ct_ptr = ct;
 641         ct->scc.fd = -1;
 642         ret = -E_CLIENT_SYNTAX;
 643         if (client_cmdline_parser(argc, argv, &ct->conf))
 644                 goto out;
 645         HANDLE_VERSION_FLAG("client", ct->conf);
 646
 647         ct->config_file = ct->conf.config_file_given?
 648                 para_strdup(ct->conf.config_file_arg) :
 649                 make_message("%s/.paraslash/client.conf", home);
 650         ret = file_exists(ct->config_file);
 651         if (!ret && ct->conf.config_file_given) {
 652                 ret = -E_NO_CONFIG;
 653                 goto out;
 654         }
 655         if (ret) {
 656                 struct client_cmdline_parser_params params = {
 657                         .override = 0,
 658                         .initialize = 0,
 659                         .check_required = 0,
 660                         .check_ambiguity = 0,
 661                         .print_errors = 0
 662                 };
 663                 ret = -E_BAD_CONFIG;
 664                 if (client_cmdline_parser_config_file(ct->config_file,
 665                         &ct->conf, &params))
 666                         goto out;
 667         }
 668         ct->user = ct->conf.user_given?
 669                 para_strdup(ct->conf.user_arg) : para_logname();
 670
 671         if (ct->conf.key_file_given)
 672                 ct->key_file = para_strdup(ct->conf.key_file_arg);
 673         else {
 674                 ct->key_file = make_message("%s/.paraslash/key.%s",
 675                         home, ct->user);
 676                 if (!file_exists(ct->key_file)) {
 677                         free(ct->key_file);
 678                         ct->key_file = make_message("%s/.ssh/id_rsa", home);
 679                 }
 680         }
 681
 682         if (loglevel)
 683                 *loglevel = get_loglevel_by_name(ct->conf.loglevel_arg);
 684         PARA_INFO_LOG("loglevel: %s\n", ct->conf.loglevel_arg);
 685         PARA_INFO_LOG("config_file: %s\n", ct->config_file);
 686         PARA_INFO_LOG("key_file: %s\n", ct->key_file);
 687         ret = ct->conf.inputs_num;
 688 out:
 689         free(home);
 690         if (ret < 0) {
 691                 PARA_ERROR_LOG("%s\n", para_strerror(-ret));
 692                 client_close(ct);
 693                 *ct_ptr = NULL;
 694         }
 695         return ret;
 696 }
 697
 698 /**
 699  * Parse the client configuration and open a connection to para_server.
 700  *
 701  * \param argc See \ref client_parse_config.
 702  * \param argv See \ref client_parse_config.
 703  * \param ct_ptr See \ref client_parse_config.
 704  * \param loglevel See \ref client_parse_config.
 705  * \param parent See \ref client_connect().
 706  * \param child See \ref client_connect().
 707  * \param sched See \ref client_connect().
 708  *
 709  * This function combines client_parse_config() and client_connect(). It is
 710  * considered a syntax error if no command was given, i.e. if the number
 711  * of non-option arguments is zero.
 712  *
 713  * \return Standard.
 714  */
 715 int client_open(int argc, char *argv[], struct client_task **ct_ptr,
 716                 int *loglevel, struct btr_node *parent, struct btr_node *child,
 717                 struct sched *sched)
 718 {
 719         int ret = client_parse_config(argc, argv, ct_ptr, loglevel);
 720
 721         if (ret < 0)
 722                 return ret;
 723         if (ret == 0) {
 724                 ret = -E_CLIENT_SYNTAX;
 725                 goto fail;
 726         }
 727         ret = client_connect(*ct_ptr, sched, parent, child);
 728         if (ret < 0)
 729                 goto fail;
 730         return 1;
 731 fail:
 732         client_close(*ct_ptr);
 733         *ct_ptr = NULL;
 734         return ret;
 735 }