client_common.c

   1 /*
   2  * Copyright (C) 1997 Andre Noll <maan@tuebingen.mpg.de>
   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 <netinet/in.h>
  10 #include <sys/socket.h>
  11 #include <regex.h>
  12 #include <sys/types.h>
  13 #include <arpa/inet.h>
  14 #include <sys/un.h>
  15 #include <netdb.h>
  16 #include <lopsub.h>
  17
  18 #include "client.lsg.h"
  19 #include "para.h"
  20 #include "error.h"
  21 #include "list.h"
  22 #include "sched.h"
  23 #include "crypt.h"
  24 #include "net.h"
  25 #include "fd.h"
  26 #include "sideband.h"
  27 #include "string.h"
  28 #include "client.h"
  29 #include "buffer_tree.h"
  30 #include "version.h"
  31
  32 /** The size of the receiving buffer. */
  33 #define CLIENT_BUFSIZE 4000
  34
  35 /**
  36  * Close the connection to para_server and free all resources.
  37  *
  38  * \param ct Pointer to the client data.
  39  *
  40  * \sa \ref client_open().
  41  */
  42 void client_close(struct client_task *ct)
  43 {
  44         if (!ct)
  45                 return;
  46         free(ct->user);
  47         free(ct->config_file);
  48         free(ct->key_file);
  49         lls_free_parse_result(ct->lpr, CLIENT_CMD_PTR);
  50         free(ct->challenge_hash);
  51         sb_free(ct->sbc[0]);
  52         sb_free(ct->sbc[1]);
  53         free(ct);
  54 }
  55
  56 /*
  57  * The preselect hook for server commands.
  58  *
  59  * The task pointer must contain a pointer to the initialized client data
  60  * structure as it is returned by client_open().
  61  *
  62  * This function checks the state of the connection and adds the file descriptor
  63  * of the connection to the read or write fd set of s accordingly.
  64  */
  65 static void client_pre_select(struct sched *s, void *context)
  66 {
  67         int ret;
  68         struct client_task *ct = context;
  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                 para_fd_set(ct->scc.fd, &s->rfds, &s->max_fileno);
  77                 return;
  78
  79         case CL_RECEIVED_WELCOME:
  80         case CL_RECEIVED_PROCEED:
  81         case CL_RECEIVED_CHALLENGE:
  82                 para_fd_set(ct->scc.fd, &s->wfds, &s->max_fileno);
  83                 return;
  84
  85         case CL_SENDING:
  86                 if (ct->btrn[1]) {
  87                         ret = btr_node_status(ct->btrn[1], 0, BTR_NT_LEAF);
  88                         if (ret < 0)
  89                                 sched_min_delay(s);
  90                         else if (ret > 0)
  91                                 para_fd_set(ct->scc.fd, &s->wfds, &s->max_fileno);
  92                 }
  93                 /* fallthrough */
  94         case CL_EXECUTING:
  95                 if (ct->btrn[0]) {
  96                         ret = btr_node_status(ct->btrn[0], 0, BTR_NT_ROOT);
  97                         if (ret < 0)
  98                                 sched_min_delay(s);
  99                         else if (ret > 0)
 100                                 para_fd_set(ct->scc.fd, &s->rfds, &s->max_fileno);
 101                 }
 102                 return;
 103         }
 104 }
 105
 106 static int send_sb(struct client_task *ct, int channel, void *buf, size_t numbytes,
 107                 enum sb_designator band, bool dont_free)
 108 {
 109         int ret, fd = ct->scc.fd;
 110         struct iovec iov[2];
 111
 112         if (!ct->sbc[channel]) {
 113                 struct sb_buffer sbb;
 114                 sb_transformation trafo = ct->status < CL_RECEIVED_PROCEED?
 115                         NULL : sc_trafo;
 116                 sbb = (typeof(sbb))SBB_INIT(band, buf, numbytes);
 117                 ct->sbc[channel] = sb_new_send(&sbb, dont_free, trafo, ct->scc.send);
 118         }
 119         ret = sb_get_send_buffers(ct->sbc[channel], iov);
 120         ret = xwritev(fd, iov, ret);
 121         if (ret < 0) {
 122                 sb_free(ct->sbc[channel]);
 123                 ct->sbc[channel] = NULL;
 124                 return ret;
 125         }
 126         if (sb_sent(ct->sbc[channel], ret)) {
 127                 ct->sbc[channel] = NULL;
 128                 return 1;
 129         }
 130         return 0;
 131 }
 132
 133 static int recv_sb(struct client_task *ct, fd_set *rfds,
 134                 struct sb_buffer *result)
 135 {
 136         int ret;
 137         size_t n;
 138         sb_transformation trafo;
 139         void *trafo_context;
 140         struct iovec iov;
 141
 142         if (!FD_ISSET(ct->scc.fd, rfds))
 143                 return 0;
 144         if (ct->status < CL_SENT_CH_RESPONSE)
 145                 trafo = trafo_context = NULL;
 146         else {
 147                 trafo = sc_trafo;
 148                 trafo_context = ct->scc.recv;
 149         }
 150         if (!ct->sbc[0])
 151                 ct->sbc[0] = sb_new_recv(0, trafo, trafo_context);
 152 again:
 153         sb_get_recv_buffer(ct->sbc[0], &iov);
 154         ret = read_nonblock(ct->scc.fd, iov.iov_base, iov.iov_len, rfds, &n);
 155         if (ret < 0) {
 156                 sb_free(ct->sbc[0]);
 157                 ct->sbc[0] = NULL;
 158                 return ret;
 159         }
 160         if (n == 0)
 161                 return 0;
 162         ret = sb_received(ct->sbc[0], n, result);
 163         if (ret < 0)
 164                 return ret;
 165         if (ret == 0)
 166                 goto again;
 167         ct->sbc[0] = NULL;
 168         return 1;
 169 }
 170
 171
 172 static char **parse_features(char *buf)
 173 {
 174         int i;
 175         const char id[] = "\nFeatures: ";
 176         char *p, *q, **features;
 177
 178         p = strstr(buf, id);
 179         if (!p)
 180                 return NULL;
 181         p += strlen(id);
 182         q = strchr(p, '\n');
 183         if (!q)
 184                 return NULL;
 185         *q = '\0';
 186         create_argv(p, ",", &features);
 187         for (i = 0; features[i]; i++)
 188                 PARA_INFO_LOG("server feature: %s\n", features[i]);
 189         return features;
 190 }
 191
 192 static int dispatch_sbb(struct client_task *ct, struct sb_buffer *sbb)
 193 {
 194         int ret;
 195         const char *designator[] = {SB_DESIGNATORS_ARRAY};
 196
 197         if (!sbb)
 198                 return 0;
 199         if (sbb->band < NUM_SB_DESIGNATORS)
 200                 PARA_DEBUG_LOG("band: %s\n", designator[sbb->band]);
 201
 202         switch (sbb->band) {
 203         case SBD_AWAITING_DATA:
 204                 ct->status = CL_SENDING;
 205                 ret = 1;
 206                 goto out;
 207         case SBD_OUTPUT:
 208                 if (iov_valid(&sbb->iov))
 209                         btr_add_output(sbb->iov.iov_base, sbb->iov.iov_len,
 210                                 ct->btrn[0]);
 211                 ret = 1;
 212                 goto out;
 213         case SBD_DEBUG_LOG:
 214         case SBD_INFO_LOG:
 215         case SBD_NOTICE_LOG:
 216         case SBD_WARNING_LOG:
 217         case SBD_ERROR_LOG:
 218         case SBD_CRIT_LOG:
 219         case SBD_EMERG_LOG:
 220                 if (iov_valid(&sbb->iov)) {
 221                         int ll = sbb->band - SBD_DEBUG_LOG;
 222                         para_log(ll, "remote: %s", (char *)sbb->iov.iov_base);
 223                 }
 224                 ret = 1;
 225                 goto deallocate;
 226         case SBD_EXIT__SUCCESS:
 227                 ret = -E_SERVER_CMD_SUCCESS;
 228                 goto deallocate;
 229         case SBD_EXIT__FAILURE:
 230                 ret = -E_SERVER_CMD_FAILURE;
 231                 goto deallocate;
 232         default:
 233                 PARA_ERROR_LOG("invalid band %d\n", sbb->band);
 234                 ret = -E_BAD_BAND;
 235                 goto deallocate;
 236         }
 237 deallocate:
 238         free(sbb->iov.iov_base);
 239 out:
 240         sbb->iov.iov_base = NULL;
 241         return ret;
 242 }
 243
 244 static int send_sb_command(struct client_task *ct)
 245 {
 246         int i;
 247         char *command, *p;
 248         size_t len = 0;
 249         unsigned num_inputs = lls_num_inputs(ct->lpr);
 250
 251         if (ct->sbc[1])
 252                 return send_sb(ct, 0, NULL, 0, 0, false);
 253
 254         for (i = 0; i < num_inputs; i++)
 255                 len += strlen(lls_input(i, ct->lpr)) + 1;
 256         p = command = para_malloc(len);
 257         for (i = 0; i < num_inputs; i++) {
 258                 const char *str = lls_input(i, ct->lpr);
 259                 strcpy(p, str);
 260                 p += strlen(str) + 1;
 261         }
 262         PARA_DEBUG_LOG("--> %s\n", command);
 263         return send_sb(ct, 0, command, len, SBD_COMMAND, false);
 264 }
 265
 266 /*
 267  * The post select hook for client commands.
 268  *
 269  * Depending on the current state of the connection and the status of the read
 270  * and write fd sets of s, this function performs the necessary steps to
 271  * authenticate the connection, to send the command given by t->private_data
 272  * and to receive para_server's output, if any.
 273  */
 274 static int client_post_select(struct sched *s, void *context)
 275 {
 276         struct client_task *ct = context;
 277         int ret = 0;
 278         size_t n;
 279         char buf[CLIENT_BUFSIZE];
 280
 281         ret = task_get_notification(ct->task);
 282         if (ret < 0)
 283                 goto out;
 284         if (ct->scc.fd < 0)
 285                 return 0;
 286         switch (ct->status) {
 287         case CL_CONNECTED: /* receive welcome message */
 288                 ret = read_nonblock(ct->scc.fd, buf, sizeof(buf), &s->rfds, &n);
 289                 if (ret < 0 || n == 0)
 290                         goto out;
 291                 ct->features = parse_features(buf);
 292                 ct->status = CL_RECEIVED_WELCOME;
 293                 return 0;
 294         case CL_RECEIVED_WELCOME: /* send auth command */
 295                 if (!FD_ISSET(ct->scc.fd, &s->wfds))
 296                         return 0;
 297                 sprintf(buf, AUTH_REQUEST_MSG "%s sideband,aes_ctr128",
 298                         ct->user);
 299                 PARA_INFO_LOG("--> %s\n", buf);
 300                 ret = write_buffer(ct->scc.fd, buf);
 301                 if (ret < 0)
 302                         goto out;
 303                 ct->status = CL_SENT_AUTH;
 304                 return 0;
 305         case CL_SENT_AUTH:
 306                 /*
 307                  * Receive challenge and session keys, decrypt the challenge and
 308                  * send back the hash of the decrypted challenge.
 309                  */
 310                 {
 311                 /* decrypted challenge/session key buffer */
 312                 unsigned char crypt_buf[1024];
 313                 struct sb_buffer sbb;
 314
 315                 ret = recv_sb(ct, &s->rfds, &sbb);
 316                 if (ret <= 0)
 317                         goto out;
 318                 if (sbb.band != SBD_CHALLENGE) {
 319                         ret = -E_BAD_BAND;
 320                         free(sbb.iov.iov_base);
 321                                 goto out;
 322                 }
 323                 n = sbb.iov.iov_len;
 324                 PARA_INFO_LOG("<-- [challenge] (%zu bytes)\n", n);
 325                 ret = priv_decrypt(ct->key_file, crypt_buf,
 326                         sbb.iov.iov_base, n);
 327                 free(sbb.iov.iov_base);
 328                 if (ret < 0)
 329                         goto out;
 330                 ct->challenge_hash = para_malloc(HASH_SIZE);
 331                 hash_function((char *)crypt_buf, CHALLENGE_SIZE, ct->challenge_hash);
 332                 ct->scc.send = sc_new(crypt_buf + CHALLENGE_SIZE, SESSION_KEY_LEN);
 333                 ct->scc.recv = sc_new(crypt_buf + CHALLENGE_SIZE + SESSION_KEY_LEN,
 334                         SESSION_KEY_LEN);
 335                 hash_to_asc(ct->challenge_hash, buf);
 336                 PARA_INFO_LOG("--> %s\n", buf);
 337                 ct->status = CL_RECEIVED_CHALLENGE;
 338                 return 0;
 339                 }
 340         case CL_RECEIVED_CHALLENGE:
 341                 ret = send_sb(ct, 0, ct->challenge_hash, HASH_SIZE,
 342                         SBD_CHALLENGE_RESPONSE, false);
 343                 if (ret != 0)
 344                         ct->challenge_hash = NULL;
 345                 if (ret <= 0)
 346                         goto out;
 347                 ct->status = CL_SENT_CH_RESPONSE;
 348                 goto out;
 349         case CL_SENT_CH_RESPONSE: /* read server response */
 350                 {
 351                 struct sb_buffer sbb;
 352                 ret = recv_sb(ct, &s->rfds, &sbb);
 353                 if (ret <= 0)
 354                         goto out;
 355                 free(sbb.iov.iov_base);
 356                 if (sbb.band != SBD_PROCEED)
 357                         ret = -E_BAD_BAND;
 358                 else
 359                         ct->status = CL_RECEIVED_PROCEED;
 360                 goto out;
 361                 }
 362         case CL_RECEIVED_PROCEED: /* concat args and send command */
 363                 {
 364                 if (!FD_ISSET(ct->scc.fd, &s->wfds))
 365                         return 0;
 366                 ret = send_sb_command(ct);
 367                 if (ret <= 0)
 368                         goto out;
 369                 ct->status = CL_EXECUTING;
 370                 return 0;
 371                 }
 372         case CL_SENDING:
 373                 if (ct->btrn[1]) {
 374                         char *buf2;
 375                         size_t sz;
 376                         ret = btr_node_status(ct->btrn[1], 0, BTR_NT_LEAF);
 377                         if (ret == -E_BTR_EOF) {
 378                                 /* empty blob data packet indicates EOF */
 379                                 PARA_INFO_LOG("blob sent\n");
 380                                 ret = send_sb(ct, 1, NULL, 0, SBD_BLOB_DATA, true);
 381                                 if (ret >= 0)
 382                                         ret = -E_BTR_EOF;
 383                         }
 384                         if (ret < 0)
 385                                 goto close1;
 386                         if (ret > 0 && FD_ISSET(ct->scc.fd, &s->wfds)) {
 387                                 sz = btr_next_buffer(ct->btrn[1], &buf2);
 388                                 assert(sz);
 389                                 ret = send_sb(ct, 1, buf2, sz, SBD_BLOB_DATA, true);
 390                                 if (ret < 0)
 391                                         goto close1;
 392                                 if (ret > 0)
 393                                         btr_consume(ct->btrn[1], sz);
 394                         }
 395                 }
 396                 /* fall through */
 397         case CL_EXECUTING:
 398                 if (ct->btrn[0]) {
 399                         ret = btr_node_status(ct->btrn[0], 0, BTR_NT_ROOT);
 400                         if (ret < 0)
 401                                 goto close0;
 402                         if (ret > 0 && FD_ISSET(ct->scc.fd, &s->rfds)) {
 403                                 struct sb_buffer sbb;
 404                                 ret = recv_sb(ct, &s->rfds, &sbb);
 405                                 if (ret < 0)
 406                                         goto close0;
 407                                 if (ret > 0) {
 408                                         ret = dispatch_sbb(ct, &sbb);
 409                                         if (ret < 0)
 410                                                 goto close0;
 411                                 }
 412                         }
 413                 }
 414                 ret = 0;
 415                 goto out;
 416         }
 417 close1:
 418         PARA_INFO_LOG("channel 1: %s\n", para_strerror(-ret));
 419         btr_remove_node(&ct->btrn[1]);
 420         if (ct->btrn[0])
 421                 return 0;
 422         goto out;
 423 close0:
 424         PARA_INFO_LOG("channel 0: %s\n", para_strerror(-ret));
 425         btr_remove_node(&ct->btrn[0]);
 426         if (ct->btrn[1] && ct->status == CL_SENDING)
 427                 return 0;
 428 out:
 429         if (ret >= 0)
 430                 return 0;
 431         btr_remove_node(&ct->btrn[0]);
 432         btr_remove_node(&ct->btrn[1]);
 433         if (ret != -E_SERVER_CMD_SUCCESS && ret != -E_SERVER_CMD_FAILURE)
 434                 PARA_ERROR_LOG("%s\n", para_strerror(-ret));
 435         if (ct->scc.fd >= 0) {
 436                 close(ct->scc.fd);
 437                 ct->scc.fd = -1;
 438         }
 439         free_argv(ct->features);
 440         ct->features = NULL;
 441         sc_free(ct->scc.recv);
 442         ct->scc.recv = NULL;
 443         sc_free(ct->scc.send);
 444         ct->scc.send = NULL;
 445         return ret;
 446 }
 447
 448 /**
 449  * Connect to para_server and register the client task.
 450  *
 451  * \param ct The initialized client task structure.
 452  * \param s The scheduler instance to register the client task to.
 453  * \param parent The parent node of the client btr node.
 454  * \param child The child node of the client node.
 455  *
 456  * The client task structure given by \a ct  must be allocated and initialized
 457  * by \ref client_parse_config() before this function is called.
 458  *
 459  * \return Standard.
 460  */
 461 int client_connect(struct client_task *ct, struct sched *s,
 462                 struct btr_node *parent, struct btr_node *child)
 463 {
 464         int ret;
 465         const char *host = CLIENT_OPT_STRING_VAL(HOSTNAME, ct->lpr);
 466         uint32_t port = CLIENT_OPT_UINT32_VAL(SERVER_PORT, ct->lpr);
 467
 468         PARA_NOTICE_LOG("connecting %s:%u\n", host, port);
 469         ct->scc.fd = -1;
 470         ret = para_connect_simple(IPPROTO_TCP, host, port);
 471         if (ret < 0)
 472                 return ret;
 473         ct->scc.fd = ret;
 474         ret = mark_fd_nonblocking(ct->scc.fd);
 475         if (ret < 0)
 476                 goto err_out;
 477         ct->status = CL_CONNECTED;
 478         ct->btrn[0] = btr_new_node(&(struct btr_node_description)
 479                 EMBRACE(.name = "client recv", .parent = NULL, .child = child));
 480         ct->btrn[1] = btr_new_node(&(struct btr_node_description)
 481                 EMBRACE(.name = "client send", .parent = parent, .child = NULL));
 482
 483         ct->task = task_register(&(struct task_info) {
 484                 .name = "client",
 485                 .pre_select = client_pre_select,
 486                 .post_select = client_post_select,
 487                 .context = ct,
 488         }, s);
 489         return 1;
 490 err_out:
 491         close(ct->scc.fd);
 492         ct->scc.fd = -1;
 493         return ret;
 494 }
 495
 496 static void handle_help_flag(struct lls_parse_result *lpr)
 497 {
 498         char *help;
 499
 500         if (CLIENT_OPT_GIVEN(DETAILED_HELP, lpr))
 501                 help = lls_long_help(CLIENT_CMD_PTR);
 502         else if (CLIENT_OPT_GIVEN(HELP, lpr))
 503                 help = lls_short_help(CLIENT_CMD_PTR);
 504         else
 505                 return;
 506         printf("%s\n", help);
 507         free(help);
 508         exit(EXIT_SUCCESS);
 509 }
 510
 511 /**
 512  * Parse a client configuration.
 513  *
 514  * \param argc Usual argument count.
 515  * \param argv Usual argument vector.
 516  * \param ct_ptr Filled in by this function.
 517  * \param loglevel If not \p NULL, the number of the loglevel is stored here.
 518  *
 519  * This checks the command line options given by \a argc and \a argv, sets
 520  * default values for the user name and the name of the rsa key file and reads
 521  * further options from the config file.
 522  *
 523  * Upon successful return, \a ct_ptr points to a dynamically allocated and
 524  * initialized client task struct.
 525  *
 526  * \return The number of non-option arguments in \a argc/argv on success,
 527  * negative on errors.
 528  */
 529 int client_parse_config(int argc, char *argv[], struct client_task **ct_ptr,
 530                 int *loglevel)
 531 {
 532         const struct lls_command *cmd = CLIENT_CMD_PTR;
 533         void *map;
 534         size_t sz;
 535         struct lls_parse_result *lpr;
 536         int ret, ll;
 537         struct client_task *ct;
 538         char *cf = NULL, *kf = NULL, *user, *errctx, *home = para_homedir();
 539
 540         ret = lls(lls_parse(argc, argv, cmd, &lpr, &errctx));
 541         if (ret < 0)
 542                 goto out;
 543         ll = CLIENT_OPT_UINT32_VAL(LOGLEVEL, lpr);
 544         version_handle_flag("client", CLIENT_OPT_GIVEN(VERSION, lpr));
 545         handle_help_flag(lpr);
 546
 547         if (CLIENT_OPT_GIVEN(CONFIG_FILE, lpr))
 548                 cf = para_strdup(CLIENT_OPT_STRING_VAL(CONFIG_FILE, lpr));
 549         else
 550                 cf = make_message("%s/.paraslash/client.conf", home);
 551         ret = mmap_full_file(cf, O_RDONLY, &map, &sz, NULL);
 552         if (ret < 0) {
 553                 if (ret != -E_EMPTY && ret != -ERRNO_TO_PARA_ERROR(ENOENT))
 554                         goto out;
 555                 if (ret == -ERRNO_TO_PARA_ERROR(ENOENT) &&
 556                                 CLIENT_OPT_GIVEN(CONFIG_FILE, lpr))
 557                         goto out;
 558         } else {
 559                 int cf_argc;
 560                 char **cf_argv;
 561                 struct lls_parse_result *cf_lpr, *merged_lpr;
 562                 ret = lls(lls_convert_config(map, sz, NULL, &cf_argv, &errctx));
 563                 para_munmap(map, sz);
 564                 if (ret < 0)
 565                         goto out;
 566                 cf_argc = ret;
 567                 ret = lls(lls_parse(cf_argc, cf_argv, cmd, &cf_lpr, &errctx));
 568                 lls_free_argv(cf_argv);
 569                 if (ret < 0)
 570                         goto out;
 571                 ret = lls(lls_merge(lpr, cf_lpr, cmd, &merged_lpr,
 572                         &errctx));
 573                 lls_free_parse_result(cf_lpr, cmd);
 574                 if (ret < 0)
 575                         goto out;
 576                 lls_free_parse_result(lpr, cmd);
 577                 lpr = merged_lpr;
 578         }
 579         /* success */
 580         user = CLIENT_OPT_GIVEN(USER, lpr)?
 581                 para_strdup(CLIENT_OPT_STRING_VAL(USER, lpr)) : para_logname();
 582
 583         if (CLIENT_OPT_GIVEN(KEY_FILE, lpr))
 584                 kf = para_strdup(CLIENT_OPT_STRING_VAL(KEY_FILE, lpr));
 585         else {
 586                 kf = make_message("%s/.paraslash/key.%s", home, user);
 587                 if (!file_exists(kf)) {
 588                         free(kf);
 589                         kf = make_message("%s/.ssh/id_rsa", home);
 590                 }
 591         }
 592         PARA_INFO_LOG("user: %s\n", user);
 593         PARA_INFO_LOG("config file: %s\n", cf);
 594         PARA_INFO_LOG("key file: %s\n", kf);
 595         PARA_INFO_LOG("loglevel: %d\n", ll);
 596         ct = para_calloc(sizeof(*ct));
 597         ct->scc.fd = -1;
 598         ct->lpr = lpr;
 599         ct->key_file = kf;
 600         ct->config_file = cf;
 601         ct->user = user;
 602         *ct_ptr = ct;
 603         if (loglevel)
 604                 *loglevel = ll;
 605         ret = lls_num_inputs(lpr);
 606 out:
 607         free(home);
 608         if (ret < 0) {
 609                 if (errctx)
 610                         PARA_ERROR_LOG("%s\n", errctx);
 611                 free(errctx);
 612                 PARA_ERROR_LOG("%s\n", para_strerror(-ret));
 613                 lls_free_parse_result(lpr, cmd);
 614                 free(cf);
 615                 free(kf);
 616                 *ct_ptr = NULL;
 617         }
 618         return ret;
 619 }
 620
 621 /**
 622  * Parse the client configuration and open a connection to para_server.
 623  *
 624  * \param argc See \ref client_parse_config.
 625  * \param argv See \ref client_parse_config.
 626  * \param ct_ptr See \ref client_parse_config.
 627  * \param loglevel See \ref client_parse_config.
 628  * \param parent See \ref client_connect().
 629  * \param child See \ref client_connect().
 630  * \param sched See \ref client_connect().
 631  *
 632  * This function combines client_parse_config() and client_connect(). It is
 633  * considered a syntax error if no command was given, i.e. if the number
 634  * of non-option arguments is zero.
 635  *
 636  * \return Standard.
 637  */
 638 int client_open(int argc, char *argv[], struct client_task **ct_ptr,
 639                 int *loglevel, struct btr_node *parent, struct btr_node *child,
 640                 struct sched *sched)
 641 {
 642         int ret = client_parse_config(argc, argv, ct_ptr, loglevel);
 643
 644         if (ret < 0)
 645                 return ret;
 646         if (ret == 0) {
 647                 ret = -E_CLIENT_SYNTAX;
 648                 goto fail;
 649         }
 650         ret = client_connect(*ct_ptr, sched, parent, child);
 651         if (ret < 0)
 652                 goto fail;
 653         return 1;
 654 fail:
 655         client_close(*ct_ptr);
 656         *ct_ptr = NULL;
 657         return ret;
 658 }