client_common.c

   1 /* Copyright (C) 1997 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
   2
   3 /** \file client_common.c Common functions of para_client and para_audiod. */
   4
   5 #include <netinet/in.h>
   6 #include <sys/socket.h>
   7 #include <regex.h>
   8 #include <sys/types.h>
   9 #include <arpa/inet.h>
  10 #include <sys/un.h>
  11 #include <netdb.h>
  12 #include <lopsub.h>
  13
  14 #include "client.lsg.h"
  15 #include "para.h"
  16 #include "error.h"
  17 #include "list.h"
  18 #include "lsu.h"
  19 #include "sched.h"
  20 #include "crypt.h"
  21 #include "net.h"
  22 #include "fd.h"
  23 #include "sideband.h"
  24 #include "string.h"
  25 #include "client.h"
  26 #include "buffer_tree.h"
  27 #include "version.h"
  28
  29 /** The size of the receiving buffer. */
  30 #define CLIENT_BUFSIZE 4000
  31
  32 /**
  33  * Close the connection to para_server and free all resources.
  34  *
  35  * \param ct Pointer to the client data.
  36  *
  37  * \sa \ref client_open().
  38  */
  39 void client_close(struct client_task *ct)
  40 {
  41         if (!ct)
  42                 return;
  43         free(ct->user);
  44         free(ct->key_file);
  45         lls_free_parse_result(ct->lpr, CLIENT_CMD_PTR);
  46         free(ct->challenge_hash);
  47         sb_free(ct->sbc[0]);
  48         sb_free(ct->sbc[1]);
  49         free(ct);
  50 }
  51
  52 /*
  53  * This function asks the scheduler to monitor a file descriptor which
  54  * corresponds to an active connection. The descriptor is monitored for either
  55  * reading or writing, depending on the state of the connection.
  56  *
  57  * The context pointer is assumed to refer to a client task structure that was
  58  * initialized earlier by client_open().
  59  */
  60 static void client_pre_monitor(struct sched *s, void *context)
  61 {
  62         int ret;
  63         struct client_task *ct = context;
  64
  65         if (ct->scc.fd < 0)
  66                 return;
  67         switch (ct->status) {
  68         case CL_CONNECTED:
  69         case CL_SENT_AUTH:
  70         case CL_SENT_CH_RESPONSE:
  71                 sched_monitor_readfd(ct->scc.fd, s);
  72                 return;
  73
  74         case CL_RECEIVED_WELCOME:
  75         case CL_RECEIVED_PROCEED:
  76         case CL_RECEIVED_CHALLENGE:
  77                 sched_monitor_writefd(ct->scc.fd, s);
  78                 return;
  79
  80         case CL_SENDING:
  81                 if (ct->btrn[1]) {
  82                         ret = btr_node_status(ct->btrn[1], 0, BTR_NT_LEAF);
  83                         if (ret < 0)
  84                                 sched_min_delay(s);
  85                         else if (ret > 0)
  86                                 sched_monitor_writefd(ct->scc.fd, s);
  87                 }
  88                 __attribute__ ((fallthrough));
  89         case CL_EXECUTING:
  90                 if (ct->btrn[0]) {
  91                         ret = btr_node_status(ct->btrn[0], 0, BTR_NT_ROOT);
  92                         if (ret < 0)
  93                                 sched_min_delay(s);
  94                         else if (ret > 0)
  95                                 sched_monitor_readfd(ct->scc.fd, s);
  96                 }
  97                 return;
  98         }
  99 }
 100
 101 static int send_sb(struct client_task *ct, int channel, void *buf, size_t numbytes,
 102                 enum sb_designator band, bool dont_free)
 103 {
 104         int ret, fd = ct->scc.fd;
 105         struct iovec iov[2];
 106
 107         if (!ct->sbc[channel]) {
 108                 struct sb_buffer sbb;
 109                 sb_transformation trafo = ct->status < CL_RECEIVED_PROCEED?
 110                         NULL : sc_trafo;
 111                 sbb = (typeof(sbb))SBB_INIT(band, buf, numbytes);
 112                 ct->sbc[channel] = sb_new_send(&sbb, dont_free, trafo, ct->scc.send);
 113         }
 114         ret = sb_get_send_buffers(ct->sbc[channel], iov);
 115         ret = xwritev(fd, iov, ret);
 116         if (ret < 0) {
 117                 sb_free(ct->sbc[channel]);
 118                 ct->sbc[channel] = NULL;
 119                 return ret;
 120         }
 121         if (sb_sent(ct->sbc[channel], ret)) {
 122                 ct->sbc[channel] = NULL;
 123                 return 1;
 124         }
 125         return 0;
 126 }
 127
 128 static int recv_sb(struct client_task *ct, struct sb_buffer *result)
 129 {
 130         int ret;
 131         size_t n;
 132         sb_transformation trafo;
 133         void *trafo_context;
 134         struct iovec iov;
 135
 136         if (ct->status < CL_SENT_CH_RESPONSE)
 137                 trafo = trafo_context = NULL;
 138         else {
 139                 trafo = sc_trafo;
 140                 trafo_context = ct->scc.recv;
 141         }
 142         if (!ct->sbc[0])
 143                 ct->sbc[0] = sb_new_recv(0, trafo, trafo_context);
 144 again:
 145         sb_get_recv_buffer(ct->sbc[0], &iov);
 146         ret = read_nonblock(ct->scc.fd, iov.iov_base, iov.iov_len, &n);
 147         if (ret < 0) {
 148                 sb_free(ct->sbc[0]);
 149                 ct->sbc[0] = NULL;
 150                 return ret;
 151         }
 152         if (n == 0)
 153                 return 0;
 154         ret = sb_received(ct->sbc[0], n, result);
 155         if (ret < 0)
 156                 return ret;
 157         if (ret == 0)
 158                 goto again;
 159         ct->sbc[0] = NULL;
 160         return 1;
 161 }
 162
 163
 164 static char **parse_features(char *buf)
 165 {
 166         int i;
 167         const char id[] = "\nFeatures: ";
 168         char *p, *q, **features;
 169
 170         p = strstr(buf, id);
 171         if (!p)
 172                 return NULL;
 173         p += strlen(id);
 174         q = strchr(p, '\n');
 175         if (!q)
 176                 return NULL;
 177         *q = '\0';
 178         create_argv(p, ",", &features);
 179         for (i = 0; features[i]; i++)
 180                 PARA_INFO_LOG("server feature: %s\n", features[i]);
 181         return features;
 182 }
 183
 184 static int dispatch_sbb(struct client_task *ct, struct sb_buffer *sbb)
 185 {
 186         int ret;
 187         const char *designator[] = {SB_DESIGNATORS_ARRAY};
 188
 189         if (!sbb)
 190                 return 0;
 191         if (sbb->band < NUM_SB_DESIGNATORS)
 192                 PARA_DEBUG_LOG("band: %s\n", designator[sbb->band]);
 193
 194         switch (sbb->band) {
 195         case SBD_AWAITING_DATA:
 196                 ct->status = CL_SENDING;
 197                 ret = 1;
 198                 goto out;
 199         case SBD_OUTPUT:
 200                 if (iov_valid(&sbb->iov))
 201                         btr_add_output(sbb->iov.iov_base, sbb->iov.iov_len,
 202                                 ct->btrn[0]);
 203                 ret = 1;
 204                 goto out;
 205         case SBD_DEBUG_LOG:
 206         case SBD_INFO_LOG:
 207         case SBD_NOTICE_LOG:
 208         case SBD_WARNING_LOG:
 209         case SBD_ERROR_LOG:
 210         case SBD_CRIT_LOG:
 211         case SBD_EMERG_LOG:
 212                 if (iov_valid(&sbb->iov)) {
 213                         int ll = sbb->band - SBD_DEBUG_LOG;
 214                         para_log(ll, "remote: %s", (char *)sbb->iov.iov_base);
 215                 }
 216                 ret = 1;
 217                 goto deallocate;
 218         case SBD_EXIT__SUCCESS:
 219                 ret = -E_SERVER_CMD_SUCCESS;
 220                 goto deallocate;
 221         case SBD_EXIT__FAILURE:
 222                 ret = -E_SERVER_CMD_FAILURE;
 223                 goto deallocate;
 224         default:
 225                 PARA_ERROR_LOG("invalid band %d\n", sbb->band);
 226                 ret = -E_BAD_BAND;
 227                 goto deallocate;
 228         }
 229 deallocate:
 230         free(sbb->iov.iov_base);
 231 out:
 232         sbb->iov.iov_base = NULL;
 233         return ret;
 234 }
 235
 236 static int send_sb_command(struct client_task *ct)
 237 {
 238         int i;
 239         char *command, *p;
 240         size_t len = 0;
 241         unsigned num_inputs = lls_num_inputs(ct->lpr);
 242
 243         if (ct->sbc[1])
 244                 return send_sb(ct, 0, NULL, 0, 0, false);
 245
 246         for (i = 0; i < num_inputs; i++)
 247                 len += strlen(lls_input(i, ct->lpr)) + 1;
 248         p = command = para_malloc(len);
 249         for (i = 0; i < num_inputs; i++) {
 250                 const char *str = lls_input(i, ct->lpr);
 251                 strcpy(p, str);
 252                 p += strlen(str) + 1;
 253         }
 254         PARA_DEBUG_LOG("--> %s\n", command);
 255         return send_sb(ct, 0, command, len, SBD_COMMAND, false);
 256 }
 257
 258 static bool has_feature(const char *feature, struct client_task *ct)
 259 {
 260         return find_arg(feature, ct->features) >= 0? true : false;
 261 }
 262
 263 /*
 264  * This function reads or writes to the socket file descriptor which
 265  * corresponds to an established connection between the client and the server.
 266  * It depends on the current state of the connection and on the readiness of
 267  * the socket file descriptor which type of I/O is going to be performed.
 268  * Besides the initial handshake and authentication, the function sends the
 269  * server command and receives the output from the server, if any.
 270  *
 271  * The context pointer refers to a client task structure that was initialized
 272  * earlier by client_open().
 273  */
 274 static int client_post_monitor(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), &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                 {
 296                 /*
 297                  * Use sha256 iff the server announced the feature. After 0.7.0
 298                  * we may request and use the feature unconditionally. After
 299                  * 0.8.0 we no longer need to request the feature.
 300                  */
 301                 bool has_sha256;
 302                 if (!sched_write_ok(ct->scc.fd, s))
 303                         return 0;
 304                 has_sha256 = has_feature("sha256", ct);
 305                 sprintf(buf, AUTH_REQUEST_MSG "%s%s", ct->user, has_sha256?
 306                         " sha256" : "");
 307                 PARA_INFO_LOG("--> %s\n", buf);
 308                 ret = write_buffer(ct->scc.fd, buf);
 309                 if (ret < 0)
 310                         goto out;
 311                 ct->status = CL_SENT_AUTH;
 312                 return 0;
 313                 }
 314         case CL_SENT_AUTH:
 315                 /*
 316                  * Receive challenge and session keys, decrypt the challenge and
 317                  * send back the hash of the decrypted challenge.
 318                  */
 319                 {
 320                 /* decrypted challenge/session key buffer */
 321                 unsigned char crypt_buf[1024];
 322                 struct sb_buffer sbb;
 323
 324                 ret = recv_sb(ct, &sbb);
 325                 if (ret <= 0)
 326                         goto out;
 327                 if (sbb.band != SBD_CHALLENGE) {
 328                         ret = -E_BAD_BAND;
 329                         free(sbb.iov.iov_base);
 330                                 goto out;
 331                 }
 332                 n = sbb.iov.iov_len;
 333                 PARA_INFO_LOG("<-- [challenge] (%zu bytes)\n", n);
 334                 ret = apc_priv_decrypt(ct->key_file, crypt_buf,
 335                         sbb.iov.iov_base, n);
 336                 free(sbb.iov.iov_base);
 337                 if (ret < 0)
 338                         goto out;
 339                 ct->challenge_hash = para_malloc(HASH2_SIZE);
 340
 341                 if (has_feature("sha256", ct)) {
 342                         hash2_function((char *)crypt_buf, APC_CHALLENGE_SIZE, ct->challenge_hash);
 343                         hash2_to_asc(ct->challenge_hash, buf);
 344                 } else {
 345                         hash_function((char *)crypt_buf, APC_CHALLENGE_SIZE, ct->challenge_hash);
 346                         hash_to_asc(ct->challenge_hash, buf);
 347                 }
 348                 ct->scc.send = sc_new(crypt_buf + APC_CHALLENGE_SIZE, SESSION_KEY_LEN);
 349                 ct->scc.recv = sc_new(crypt_buf + APC_CHALLENGE_SIZE + SESSION_KEY_LEN,
 350                         SESSION_KEY_LEN);
 351                 PARA_INFO_LOG("--> %s\n", buf);
 352                 ct->status = CL_RECEIVED_CHALLENGE;
 353                 return 0;
 354                 }
 355         case CL_RECEIVED_CHALLENGE:
 356                 if (has_feature("sha256", ct))
 357                         ret = send_sb(ct, 0, ct->challenge_hash, HASH2_SIZE,
 358                                 SBD_CHALLENGE_RESPONSE, false);
 359                 else
 360                         ret = send_sb(ct, 0, ct->challenge_hash, HASH_SIZE,
 361                                 SBD_CHALLENGE_RESPONSE, false);
 362                 if (ret != 0)
 363                         ct->challenge_hash = NULL;
 364                 if (ret <= 0)
 365                         goto out;
 366                 ct->status = CL_SENT_CH_RESPONSE;
 367                 goto out;
 368         case CL_SENT_CH_RESPONSE: /* read server response */
 369                 {
 370                 struct sb_buffer sbb;
 371                 ret = recv_sb(ct, &sbb);
 372                 if (ret <= 0)
 373                         goto out;
 374                 free(sbb.iov.iov_base);
 375                 if (sbb.band != SBD_PROCEED)
 376                         ret = -E_BAD_BAND;
 377                 else
 378                         ct->status = CL_RECEIVED_PROCEED;
 379                 goto out;
 380                 }
 381         case CL_RECEIVED_PROCEED: /* concat args and send command */
 382                 {
 383                 if (!sched_write_ok(ct->scc.fd, s))
 384                         return 0;
 385                 ret = send_sb_command(ct);
 386                 if (ret <= 0)
 387                         goto out;
 388                 ct->status = CL_EXECUTING;
 389                 return 0;
 390                 }
 391         case CL_SENDING:
 392                 if (ct->btrn[1]) {
 393                         char *buf2;
 394                         size_t sz;
 395                         ret = btr_node_status(ct->btrn[1], 0, BTR_NT_LEAF);
 396                         if (ret == -E_BTR_EOF) {
 397                                 /* empty blob data packet indicates EOF */
 398                                 PARA_INFO_LOG("blob sent\n");
 399                                 ret = send_sb(ct, 1, NULL, 0, SBD_BLOB_DATA, true);
 400                                 if (ret >= 0)
 401                                         ret = -E_BTR_EOF;
 402                         }
 403                         if (ret < 0)
 404                                 goto close1;
 405                         if (ret > 0 && sched_write_ok(ct->scc.fd, s)) {
 406                                 sz = btr_next_buffer(ct->btrn[1], &buf2);
 407                                 assert(sz);
 408                                 ret = send_sb(ct, 1, buf2, sz, SBD_BLOB_DATA, true);
 409                                 if (ret < 0)
 410                                         goto close1;
 411                                 if (ret > 0)
 412                                         btr_consume(ct->btrn[1], sz);
 413                         }
 414                 }
 415                 __attribute__ ((fallthrough));
 416         case CL_EXECUTING:
 417                 if (ct->btrn[0]) {
 418                         ret = btr_node_status(ct->btrn[0], 0, BTR_NT_ROOT);
 419                         if (ret < 0)
 420                                 goto close0;
 421                         if (ret > 0 && sched_read_ok(ct->scc.fd, s)) {
 422                                 struct sb_buffer sbb;
 423                                 ret = recv_sb(ct, &sbb);
 424                                 if (ret < 0)
 425                                         goto close0;
 426                                 if (ret > 0) {
 427                                         ret = dispatch_sbb(ct, &sbb);
 428                                         if (ret < 0)
 429                                                 goto close0;
 430                                 }
 431                         }
 432                 }
 433                 ret = 0;
 434                 goto out;
 435         }
 436 close1:
 437         PARA_INFO_LOG("channel 1: %s\n", para_strerror(-ret));
 438         btr_remove_node(&ct->btrn[1]);
 439         if (ct->btrn[0])
 440                 return 0;
 441         goto out;
 442 close0:
 443         PARA_INFO_LOG("channel 0: %s\n", para_strerror(-ret));
 444         btr_remove_node(&ct->btrn[0]);
 445         if (ct->btrn[1] && ct->status == CL_SENDING)
 446                 return 0;
 447 out:
 448         if (ret >= 0)
 449                 return 0;
 450         btr_remove_node(&ct->btrn[0]);
 451         btr_remove_node(&ct->btrn[1]);
 452         PARA_NOTICE_LOG("closing connection (%s)\n", para_strerror(-ret));
 453         if (ct->scc.fd >= 0) {
 454                 close(ct->scc.fd);
 455                 ct->scc.fd = -1;
 456         }
 457         free_argv(ct->features);
 458         ct->features = NULL;
 459         sc_free(ct->scc.recv);
 460         ct->scc.recv = NULL;
 461         sc_free(ct->scc.send);
 462         ct->scc.send = NULL;
 463         return ret;
 464 }
 465
 466 /**
 467  * Connect to para_server and register the client task.
 468  *
 469  * \param ct The initialized client task structure.
 470  * \param s The scheduler instance to register the client task to.
 471  * \param parent The parent node of the client btr node.
 472  * \param child The child node of the client node.
 473  *
 474  * The client task structure given by \a ct  must be allocated and initialized
 475  * by \ref client_parse_config() before this function is called.
 476  *
 477  * \return Standard.
 478  */
 479 int client_connect(struct client_task *ct, struct sched *s,
 480                 struct btr_node *parent, struct btr_node *child)
 481 {
 482         int ret;
 483         const char *host = CLIENT_OPT_STRING_VAL(HOSTNAME, ct->lpr);
 484         uint32_t port = CLIENT_OPT_UINT32_VAL(SERVER_PORT, ct->lpr);
 485
 486         PARA_NOTICE_LOG("connecting %s:%u\n", host, port);
 487         ct->scc.fd = -1;
 488         ret = para_connect_simple(IPPROTO_TCP, host, port);
 489         if (ret < 0)
 490                 return ret;
 491         ct->scc.fd = ret;
 492         ret = mark_fd_nonblocking(ct->scc.fd);
 493         if (ret < 0)
 494                 goto err_out;
 495         ct->status = CL_CONNECTED;
 496         ct->btrn[0] = btr_new_node(&(struct btr_node_description)
 497                 EMBRACE(.name = "client recv", .parent = NULL, .child = child));
 498         ct->btrn[1] = btr_new_node(&(struct btr_node_description)
 499                 EMBRACE(.name = "client send", .parent = parent, .child = NULL));
 500
 501         ct->task = task_register(&(struct task_info) {
 502                 .name = "client",
 503                 .pre_monitor = client_pre_monitor,
 504                 .post_monitor = client_post_monitor,
 505                 .context = ct,
 506         }, s);
 507         return 1;
 508 err_out:
 509         close(ct->scc.fd);
 510         ct->scc.fd = -1;
 511         return ret;
 512 }
 513
 514 static void handle_help_flag(struct lls_parse_result *lpr)
 515 {
 516         char *help;
 517
 518         if (CLIENT_OPT_GIVEN(DETAILED_HELP, lpr))
 519                 help = lls_long_help(CLIENT_CMD_PTR);
 520         else if (CLIENT_OPT_GIVEN(HELP, lpr))
 521                 help = lls_short_help(CLIENT_CMD_PTR);
 522         else
 523                 return;
 524         printf("%s\n", help);
 525         free(help);
 526         exit(EXIT_SUCCESS);
 527 }
 528
 529 /**
 530  * Parse a client configuration.
 531  *
 532  * \param argc Usual argument count.
 533  * \param argv Usual argument vector.
 534  * \param ct_ptr Filled in by this function.
 535  * \param loglevel If not \p NULL, the number of the loglevel is stored here.
 536  *
 537  * This checks the command line options given by \a argc and \a argv, sets
 538  * default values for the user name and the name of the rsa key file and reads
 539  * further options from the config file.
 540  *
 541  * Upon successful return, \a ct_ptr points to a dynamically allocated and
 542  * initialized client task struct.
 543  *
 544  * \return The number of non-option arguments in \a argc/argv on success,
 545  * negative on errors.
 546  */
 547 int client_parse_config(int argc, char *argv[], struct client_task **ct_ptr,
 548                 int *loglevel)
 549 {
 550         const struct lls_command *cmd = CLIENT_CMD_PTR;
 551         struct lls_parse_result *lpr;
 552         int ret, ll;
 553         struct client_task *ct;
 554         char *kf = NULL, *user, *errctx, *home = para_homedir();
 555
 556         ret = lls(lls_parse(argc, argv, cmd, &lpr, &errctx));
 557         if (ret < 0)
 558                 goto out;
 559         version_handle_flag("client", CLIENT_OPT_GIVEN(VERSION, lpr));
 560         handle_help_flag(lpr);
 561
 562         ret = lsu_merge_config_file_options(CLIENT_OPT_STRING_VAL(CONFIG_FILE, lpr),
 563                 "client.conf", &lpr, cmd, client_suite, 0U /* default flags */);
 564         if (ret < 0)
 565                 goto out;
 566         /* success */
 567         ll = CLIENT_OPT_UINT32_VAL(LOGLEVEL, lpr);
 568         if (loglevel)
 569                 *loglevel = ll;
 570         user = CLIENT_OPT_GIVEN(USER, lpr)?
 571                 para_strdup(CLIENT_OPT_STRING_VAL(USER, lpr)) : para_logname();
 572
 573         if (CLIENT_OPT_GIVEN(KEY_FILE, lpr))
 574                 kf = para_strdup(CLIENT_OPT_STRING_VAL(KEY_FILE, lpr));
 575         else {
 576                 kf = make_message("%s/.paraslash/key.%s", home, user);
 577                 if (!file_exists(kf)) {
 578                         free(kf);
 579                         kf = make_message("%s/.ssh/id_rsa", home);
 580                 }
 581         }
 582         PARA_INFO_LOG("user: %s\n", user);
 583         PARA_INFO_LOG("key file: %s\n", kf);
 584         PARA_INFO_LOG("loglevel: %d\n", ll);
 585         ct = para_calloc(sizeof(*ct));
 586         ct->scc.fd = -1;
 587         ct->lpr = lpr;
 588         ct->key_file = kf;
 589         ct->user = user;
 590         *ct_ptr = ct;
 591         ret = lls_num_inputs(lpr);
 592 out:
 593         free(home);
 594         if (ret < 0) {
 595                 if (errctx)
 596                         PARA_ERROR_LOG("%s\n", errctx);
 597                 free(errctx);
 598                 lls_free_parse_result(lpr, cmd);
 599                 free(kf);
 600                 *ct_ptr = NULL;
 601         }
 602         return ret;
 603 }
 604
 605 /**
 606  * Parse the client configuration and open a connection to para_server.
 607  *
 608  * \param argc See \ref client_parse_config.
 609  * \param argv See \ref client_parse_config.
 610  * \param ct_ptr See \ref client_parse_config.
 611  * \param loglevel See \ref client_parse_config.
 612  * \param parent See \ref client_connect().
 613  * \param child See \ref client_connect().
 614  * \param sched See \ref client_connect().
 615  *
 616  * This function combines client_parse_config() and client_connect(). It is
 617  * considered a syntax error if no command was given, i.e. if the number
 618  * of non-option arguments is zero.
 619  *
 620  * \return Standard.
 621  */
 622 int client_open(int argc, char *argv[], struct client_task **ct_ptr,
 623                 int *loglevel, struct btr_node *parent, struct btr_node *child,
 624                 struct sched *sched)
 625 {
 626         int ret = client_parse_config(argc, argv, ct_ptr, loglevel);
 627
 628         if (ret < 0)
 629                 return ret;
 630         if (ret == 0) {
 631                 ret = -E_CLIENT_SYNTAX;
 632                 goto fail;
 633         }
 634         ret = client_connect(*ct_ptr, sched, parent, child);
 635         if (ret < 0)
 636                 goto fail;
 637         return 1;
 638 fail:
 639         client_close(*ct_ptr);
 640         *ct_ptr = NULL;
 641         return ret;
 642 }