src/lxc/terminal.c

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2
   3 #ifndef _GNU_SOURCE
   4 #define _GNU_SOURCE 1
   5 #endif
   6 #include <errno.h>
   7 #include <fcntl.h>
   8 #include <lxc/lxccontainer.h>
   9 #include <pthread.h>
  10 #include <signal.h>
  11 #include <stdio.h>
  12 #include <stdlib.h>
  13 #include <sys/epoll.h>
  14 #include <sys/types.h>
  15 #include <termios.h>
  16 #include <unistd.h>
  17
  18 #include "af_unix.h"
  19 #include "caps.h"
  20 #include "commands.h"
  21 #include "conf.h"
  22 #include "config.h"
  23 #include "log.h"
  24 #include "lxclock.h"
  25 #include "mainloop.h"
  26 #include "memory_utils.h"
  27 #include "start.h"
  28 #include "syscall_wrappers.h"
  29 #include "terminal.h"
  30 #include "utils.h"
  31
  32 #if HAVE_OPENPTY
  33 #include <pty.h>
  34 #else
  35 #include "openpty.h"
  36 #endif
  37
  38 #define LXC_TERMINAL_BUFFER_SIZE 1024
  39
  40 lxc_log_define(terminal, lxc);
  41
  42 void lxc_terminal_winsz(int srcfd, int dstfd)
  43 {
  44         int ret;
  45         struct winsize wsz;
  46
  47         if (!isatty(srcfd))
  48                 return;
  49
  50         ret = ioctl(srcfd, TIOCGWINSZ, &wsz);
  51         if (ret < 0) {
  52                 WARN("Failed to get window size");
  53                 return;
  54         }
  55
  56         ret = ioctl(dstfd, TIOCSWINSZ, &wsz);
  57         if (ret < 0)
  58                 WARN("Failed to set window size");
  59         else
  60                 DEBUG("Set window size to %d columns and %d rows", wsz.ws_col,
  61                       wsz.ws_row);
  62
  63         return;
  64 }
  65
  66 static void lxc_terminal_winch(struct lxc_terminal_state *ts)
  67 {
  68         lxc_terminal_winsz(ts->stdinfd, ts->ptxfd);
  69 }
  70
  71 int lxc_terminal_signalfd_cb(int fd, uint32_t events, void *cbdata,
  72                              struct lxc_async_descr *descr)
  73 {
  74         ssize_t ret;
  75         struct signalfd_siginfo siginfo;
  76         struct lxc_terminal_state *ts = cbdata;
  77
  78         ret = lxc_read_nointr(fd, &siginfo, sizeof(siginfo));
  79         if (ret < 0 || (size_t)ret < sizeof(siginfo)) {
  80                 ERROR("Failed to read signal info");
  81                 return LXC_MAINLOOP_ERROR;
  82         }
  83
  84         if (siginfo.ssi_signo == SIGTERM) {
  85                 DEBUG("Received SIGTERM. Detaching from the terminal");
  86                 return LXC_MAINLOOP_CLOSE;
  87         }
  88
  89         if (siginfo.ssi_signo == SIGWINCH)
  90                 lxc_terminal_winch(ts);
  91
  92         return LXC_MAINLOOP_CONTINUE;
  93 }
  94
  95 struct lxc_terminal_state *lxc_terminal_signal_init(int srcfd, int dstfd)
  96 {
  97         __do_close int signal_fd = -EBADF;
  98         __do_free struct lxc_terminal_state *ts = NULL;
  99         int ret;
 100         sigset_t mask;
 101
 102         ts = malloc(sizeof(*ts));
 103         if (!ts)
 104                 return NULL;
 105
 106         memset(ts, 0, sizeof(*ts));
 107         ts->stdinfd = srcfd;
 108         ts->ptxfd = dstfd;
 109         ts->sigfd = -1;
 110
 111         ret = sigemptyset(&mask);
 112         if (ret < 0) {
 113                 SYSERROR("Failed to initialize an empty signal set");
 114                 return NULL;
 115         }
 116
 117         if (isatty(srcfd)) {
 118                 ret = sigaddset(&mask, SIGWINCH);
 119                 if (ret < 0)
 120                         SYSNOTICE("Failed to add SIGWINCH to signal set");
 121         } else {
 122                 INFO("fd %d does not refer to a tty device", srcfd);
 123         }
 124
 125         /* Exit the mainloop cleanly on SIGTERM. */
 126         ret = sigaddset(&mask, SIGTERM);
 127         if (ret < 0) {
 128                 SYSERROR("Failed to add SIGWINCH to signal set");
 129                 return NULL;
 130         }
 131
 132         ret = pthread_sigmask(SIG_BLOCK, &mask, &ts->oldmask);
 133         if (ret < 0) {
 134                 WARN("Failed to block signals");
 135                 return NULL;
 136         }
 137
 138         signal_fd = signalfd(-1, &mask, SFD_CLOEXEC);
 139         if (signal_fd < 0) {
 140                 WARN("Failed to create signal fd");
 141                 (void)pthread_sigmask(SIG_SETMASK, &ts->oldmask, NULL);
 142                 return NULL;
 143         }
 144         ts->sigfd = move_fd(signal_fd);
 145         TRACE("Created signal fd %d", ts->sigfd);
 146
 147         return move_ptr(ts);
 148 }
 149
 150 int lxc_terminal_signal_sigmask_safe_blocked(struct lxc_terminal *terminal)
 151 {
 152         struct lxc_terminal_state *state = terminal->tty_state;
 153
 154         if (!state)
 155                 return 0;
 156
 157         return pthread_sigmask(SIG_SETMASK, &state->oldmask, NULL);
 158 }
 159
 160 /**
 161  * lxc_terminal_signal_fini: uninstall signal handler
 162  *
 163  * @terminal: terminal instance
 164  *
 165  * Restore the saved signal handler that was in effect at the time
 166  * lxc_terminal_signal_init() was called.
 167  */
 168 static void lxc_terminal_signal_fini(struct lxc_terminal *terminal)
 169 {
 170         struct lxc_terminal_state *state = terminal->tty_state;
 171
 172         if (!terminal->tty_state)
 173                 return;
 174
 175         state = terminal->tty_state;
 176         if (state->sigfd >= 0) {
 177                 close(state->sigfd);
 178
 179                 if (pthread_sigmask(SIG_SETMASK, &state->oldmask, NULL) < 0)
 180                         SYSWARN("Failed to restore signal mask");
 181         }
 182
 183         free(terminal->tty_state);
 184         terminal->tty_state = NULL;
 185 }
 186
 187 static int lxc_terminal_truncate_log_file(struct lxc_terminal *terminal)
 188 {
 189         /* be very certain things are kosher */
 190         if (!terminal->log_path || terminal->log_fd < 0)
 191                 return -EBADF;
 192
 193         return lxc_unpriv(ftruncate(terminal->log_fd, 0));
 194 }
 195
 196 static int lxc_terminal_rotate_log_file(struct lxc_terminal *terminal)
 197 {
 198         __do_free char *tmp = NULL;
 199         int ret;
 200         size_t len;
 201
 202         if (!terminal->log_path || terminal->log_rotate == 0)
 203                 return -EOPNOTSUPP;
 204
 205         /* be very certain things are kosher */
 206         if (terminal->log_fd < 0)
 207                 return -EBADF;
 208
 209         len = strlen(terminal->log_path) + sizeof(".1");
 210         tmp = must_realloc(NULL, len);
 211
 212         ret = strnprintf(tmp, len, "%s.1", terminal->log_path);
 213         if (ret < 0)
 214                 return -EFBIG;
 215
 216         close(terminal->log_fd);
 217         terminal->log_fd = -1;
 218         ret = lxc_unpriv(rename(terminal->log_path, tmp));
 219         if (ret < 0)
 220                 return ret;
 221
 222         return lxc_terminal_create_log_file(terminal);
 223 }
 224
 225 static int lxc_terminal_write_log_file(struct lxc_terminal *terminal, char *buf,
 226                                        int bytes_read)
 227 {
 228         int ret;
 229         struct stat st;
 230         int64_t space_left = -1;
 231
 232         if (terminal->log_fd < 0)
 233                 return 0;
 234
 235         /* A log size <= 0 means that there's no limit on the size of the log
 236          * file at which point we simply ignore whether the log is supposed to
 237          * be rotated or not.
 238          */
 239         if (terminal->log_size <= 0)
 240                 return lxc_write_nointr(terminal->log_fd, buf, bytes_read);
 241
 242         /* Get current size of the log file. */
 243         ret = fstat(terminal->log_fd, &st);
 244         if (ret < 0) {
 245                 SYSERROR("Failed to stat the terminal log file descriptor");
 246                 return -1;
 247         }
 248
 249         /* handle non-regular files */
 250         if ((st.st_mode & S_IFMT) != S_IFREG) {
 251                 /* This isn't a regular file. so rotating the file seems a
 252                  * dangerous thing to do, size limits are also very
 253                  * questionable. Let's not risk anything and tell the user that
 254                  * they're requesting us to do weird stuff.
 255                  */
 256                 if (terminal->log_rotate > 0 || terminal->log_size > 0)
 257                         return -EINVAL;
 258
 259                 /* I mean, sure log wherever you want to. */
 260                 return lxc_write_nointr(terminal->log_fd, buf, bytes_read);
 261         }
 262
 263         space_left = terminal->log_size - st.st_size;
 264
 265         /* User doesn't want to rotate the log file and there's no more space
 266          * left so simply truncate it.
 267          */
 268         if (space_left <= 0 && terminal->log_rotate <= 0) {
 269                 ret = lxc_terminal_truncate_log_file(terminal);
 270                 if (ret < 0)
 271                         return ret;
 272
 273                 if ((uint64_t)bytes_read <= terminal->log_size)
 274                         return lxc_write_nointr(terminal->log_fd, buf, bytes_read);
 275
 276                 /* Write as much as we can into the buffer and loose the rest. */
 277                 return lxc_write_nointr(terminal->log_fd, buf, terminal->log_size);
 278         }
 279
 280         /* There's enough space left. */
 281         if (bytes_read <= space_left)
 282                 return lxc_write_nointr(terminal->log_fd, buf, bytes_read);
 283
 284         /* There's not enough space left but at least write as much as we can
 285          * into the old log file.
 286          */
 287         ret = lxc_write_nointr(terminal->log_fd, buf, space_left);
 288         if (ret < 0)
 289                 return -1;
 290
 291         /* Calculate how many bytes we still need to write. */
 292         bytes_read -= space_left;
 293
 294         /* There'd be more to write but we aren't instructed to rotate the log
 295          * file so simply return. There's no error on our side here.
 296          */
 297         if (terminal->log_rotate > 0)
 298                 ret = lxc_terminal_rotate_log_file(terminal);
 299         else
 300                 ret = lxc_terminal_truncate_log_file(terminal);
 301         if (ret < 0)
 302                 return ret;
 303
 304         if (terminal->log_size < (uint64_t)bytes_read) {
 305                 /* Well, this is unfortunate because it means that there is more
 306                  * to write than the user has granted us space. There are
 307                  * multiple ways to handle this but let's use the simplest one:
 308                  * write as much as we can, tell the user that there was more
 309                  * stuff to write and move on.
 310                  * Note that this scenario shouldn't actually happen with the
 311                  * standard pty-based terminal that LXC allocates since it will
 312                  * be switched into raw mode. In raw mode only 1 byte at a time
 313                  * should be read and written.
 314                  */
 315                 WARN("Size of terminal log file is smaller than the bytes to write");
 316                 ret = lxc_write_nointr(terminal->log_fd, buf, terminal->log_size);
 317                 if (ret < 0)
 318                         return -1;
 319                 bytes_read -= ret;
 320                 return bytes_read;
 321         }
 322
 323         /* Yay, we made it. */
 324         ret = lxc_write_nointr(terminal->log_fd, buf, bytes_read);
 325         if (ret < 0)
 326                 return -1;
 327         bytes_read -= ret;
 328         return bytes_read;
 329 }
 330
 331 static int lxc_terminal_ptx_io(struct lxc_terminal *terminal)
 332 {
 333         char buf[LXC_TERMINAL_BUFFER_SIZE];
 334         int r, w, w_log, w_rbuf;
 335
 336         w = r = lxc_read_nointr(terminal->ptx, buf, sizeof(buf));
 337         if (r <= 0)
 338                 return -1;
 339
 340         w_rbuf = w_log = 0;
 341         /* write to peer first */
 342         if (terminal->peer >= 0)
 343                 w = lxc_write_nointr(terminal->peer, buf, r);
 344
 345         /* write to terminal ringbuffer */
 346         if (terminal->buffer_size > 0)
 347                 w_rbuf = lxc_ringbuf_write(&terminal->ringbuf, buf, r);
 348
 349         /* write to terminal log */
 350         if (terminal->log_fd >= 0)
 351                 w_log = lxc_terminal_write_log_file(terminal, buf, r);
 352
 353         if (w != r)
 354                 WARN("Short write on terminal r:%d != w:%d", r, w);
 355
 356         if (w_rbuf < 0) {
 357                 errno = -w_rbuf;
 358                 SYSTRACE("Failed to write %d bytes to terminal ringbuffer", r);
 359         }
 360
 361         if (w_log < 0)
 362                 TRACE("Failed to write %d bytes to terminal log", r);
 363
 364         return 0;
 365 }
 366
 367 static int lxc_terminal_peer_io(struct lxc_terminal *terminal)
 368 {
 369         char buf[LXC_TERMINAL_BUFFER_SIZE];
 370         int r, w;
 371
 372         w = r = lxc_read_nointr(terminal->peer, buf, sizeof(buf));
 373         if (r <= 0)
 374                 return -1;
 375
 376         w = lxc_write_nointr(terminal->ptx, buf, r);
 377         if (w != r)
 378                 WARN("Short write on terminal r:%d != w:%d", r, w);
 379
 380         return 0;
 381 }
 382
 383 static int lxc_terminal_ptx_io_handler(int fd, uint32_t events, void *data,
 384                                        struct lxc_async_descr *descr)
 385 {
 386         struct lxc_terminal *terminal = data;
 387         int ret;
 388
 389         ret = lxc_terminal_ptx_io(data);
 390         if (ret < 0)
 391                 return log_info(LXC_MAINLOOP_CLOSE,
 392                                 "Terminal client on fd %d has exited",
 393                                 terminal->ptx);
 394
 395         return LXC_MAINLOOP_CONTINUE;
 396 }
 397
 398 static int lxc_terminal_peer_io_handler(int fd, uint32_t events, void *data,
 399                                         struct lxc_async_descr *descr)
 400 {
 401         struct lxc_terminal *terminal = data;
 402         int ret;
 403
 404         ret = lxc_terminal_peer_io(data);
 405         if (ret < 0)
 406                 return log_info(LXC_MAINLOOP_CLOSE,
 407                                 "Terminal client on fd %d has exited",
 408                                 terminal->peer);
 409
 410         return LXC_MAINLOOP_CONTINUE;
 411 }
 412
 413 static int lxc_terminal_mainloop_add_peer(struct lxc_terminal *terminal)
 414 {
 415         int ret;
 416
 417         if (terminal->peer >= 0) {
 418                 ret = lxc_mainloop_add_handler(terminal->descr, terminal->peer,
 419                                                lxc_terminal_peer_io_handler,
 420                                                default_cleanup_handler,
 421                                                terminal, "lxc_terminal_peer_io_handler");
 422                 if (ret < 0) {
 423                         WARN("Failed to add terminal peer handler to mainloop");
 424                         return -1;
 425                 }
 426         }
 427
 428         if (!terminal->tty_state || terminal->tty_state->sigfd < 0)
 429                 return 0;
 430
 431         ret = lxc_mainloop_add_handler(terminal->descr,
 432                                        terminal->tty_state->sigfd,
 433                                        lxc_terminal_signalfd_cb,
 434                                        default_cleanup_handler,
 435                                        terminal->tty_state,
 436                                        "lxc_terminal_signalfd_cb");
 437         if (ret < 0) {
 438                 WARN("Failed to add signal handler to mainloop");
 439                 return -1;
 440         }
 441
 442         return 0;
 443 }
 444
 445 int lxc_terminal_mainloop_add(struct lxc_async_descr *descr,
 446                               struct lxc_terminal *terminal)
 447 {
 448         int ret;
 449
 450         if (terminal->ptx < 0) {
 451                 INFO("Terminal is not initialized");
 452                 return 0;
 453         }
 454
 455         ret = lxc_mainloop_add_handler(descr, terminal->ptx,
 456                                        lxc_terminal_ptx_io_handler,
 457                                        default_cleanup_handler,
 458                                        terminal, "lxc_terminal_ptx_io_handler");
 459         if (ret < 0) {
 460                 ERROR("Failed to add handler for terminal ptx fd %d to mainloop", terminal->ptx);
 461                 return -1;
 462         }
 463
 464         /* We cache the descr so that we can add an fd to it when someone
 465          * does attach to it in lxc_terminal_allocate().
 466          */
 467         terminal->descr = descr;
 468
 469         return lxc_terminal_mainloop_add_peer(terminal);
 470 }
 471
 472 int lxc_setup_tios(int fd, struct termios *oldtios)
 473 {
 474         int ret;
 475         struct termios newtios;
 476
 477         if (!isatty(fd)) {
 478                 ERROR("File descriptor %d does not refer to a terminal", fd);
 479                 return -1;
 480         }
 481
 482         /* Get current termios. */
 483         ret = tcgetattr(fd, oldtios);
 484         if (ret < 0) {
 485                 SYSERROR("Failed to get current terminal settings");
 486                 return -1;
 487         }
 488
 489         /* ensure we don't end up in an endless loop:
 490          * The kernel might fire SIGTTOU while an
 491          * ioctl() in tcsetattr() is executed. When the ioctl()
 492          * is resumed and retries, the signal handler interrupts it again.
 493          */
 494         signal (SIGTTIN, SIG_IGN);
 495         signal (SIGTTOU, SIG_IGN);
 496
 497         newtios = *oldtios;
 498
 499         /* We use the same settings that ssh does. */
 500         newtios.c_iflag |= IGNPAR;
 501         newtios.c_iflag &= ~(ISTRIP | INLCR | IGNCR | ICRNL | IXON | IXANY | IXOFF);
 502 #ifdef IUCLC
 503         newtios.c_iflag &= ~IUCLC;
 504 #endif
 505         newtios.c_lflag &= ~(TOSTOP | ISIG | ICANON | ECHO | ECHOE | ECHOK | ECHONL);
 506 #ifdef IEXTEN
 507         newtios.c_lflag &= ~IEXTEN;
 508 #endif
 509         newtios.c_oflag |= ONLCR;
 510         newtios.c_oflag |= OPOST;
 511         newtios.c_cc[VMIN] = 1;
 512         newtios.c_cc[VTIME] = 0;
 513
 514         /* Set new attributes. */
 515         ret = tcsetattr(fd, TCSAFLUSH, &newtios);
 516         if (ret < 0) {
 517                 ERROR("Failed to set new terminal settings");
 518                 return -1;
 519         }
 520
 521         return 0;
 522 }
 523
 524 static void lxc_terminal_peer_proxy_free(struct lxc_terminal *terminal)
 525 {
 526         lxc_terminal_signal_fini(terminal);
 527
 528         close(terminal->proxy.ptx);
 529         terminal->proxy.ptx = -1;
 530
 531         close(terminal->proxy.pty);
 532         terminal->proxy.pty = -1;
 533
 534         terminal->proxy.busy = -1;
 535
 536         terminal->proxy.name[0] = '\0';
 537
 538         terminal->peer = -1;
 539 }
 540
 541 static int lxc_terminal_peer_proxy_alloc(struct lxc_terminal *terminal,
 542                                          int sockfd)
 543 {
 544         int ret;
 545         struct termios oldtermio;
 546         struct lxc_terminal_state *ts;
 547
 548         if (terminal->ptx < 0) {
 549                 ERROR("Terminal not set up");
 550                 return -1;
 551         }
 552
 553         if (terminal->proxy.busy != -1 || terminal->peer != -1) {
 554                 NOTICE("Terminal already in use");
 555                 return -1;
 556         }
 557
 558         if (terminal->tty_state) {
 559                 ERROR("Terminal has already been initialized");
 560                 return -1;
 561         }
 562
 563         /* This is the proxy terminal that will be given to the client, and
 564          * that the real terminal ptx will send to / recv from.
 565          */
 566         ret = openpty(&terminal->proxy.ptx, &terminal->proxy.pty, NULL,
 567                       NULL, NULL);
 568         if (ret < 0) {
 569                 SYSERROR("Failed to open proxy terminal");
 570                 return -1;
 571         }
 572
 573         ret = ttyname_r(terminal->proxy.pty, terminal->proxy.name,
 574                         sizeof(terminal->proxy.name));
 575         if (ret < 0) {
 576                 SYSERROR("Failed to retrieve name of proxy terminal pty");
 577                 goto on_error;
 578         }
 579
 580         ret = fd_cloexec(terminal->proxy.ptx, true);
 581         if (ret < 0) {
 582                 SYSERROR("Failed to set FD_CLOEXEC flag on proxy terminal ptx");
 583                 goto on_error;
 584         }
 585
 586         ret = fd_cloexec(terminal->proxy.pty, true);
 587         if (ret < 0) {
 588                 SYSERROR("Failed to set FD_CLOEXEC flag on proxy terminal pty");
 589                 goto on_error;
 590         }
 591
 592         ret = lxc_setup_tios(terminal->proxy.pty, &oldtermio);
 593         if (ret < 0)
 594                 goto on_error;
 595
 596         ts = lxc_terminal_signal_init(terminal->proxy.ptx, terminal->ptx);
 597         if (!ts)
 598                 goto on_error;
 599
 600         terminal->tty_state = ts;
 601         terminal->peer = terminal->proxy.pty;
 602         terminal->proxy.busy = sockfd;
 603         ret = lxc_terminal_mainloop_add_peer(terminal);
 604         if (ret < 0)
 605                 goto on_error;
 606
 607         NOTICE("Opened proxy terminal with ptx fd %d and pty fd %d",
 608                terminal->proxy.ptx, terminal->proxy.pty);
 609         return 0;
 610
 611 on_error:
 612         lxc_terminal_peer_proxy_free(terminal);
 613         return -1;
 614 }
 615
 616 int lxc_terminal_allocate(struct lxc_conf *conf, int sockfd, int *ttyreq)
 617 {
 618         size_t ttynum;
 619         int ptxfd = -1;
 620         struct lxc_tty_info *ttys = &conf->ttys;
 621         struct lxc_terminal *terminal = &conf->console;
 622
 623         if (*ttyreq == 0) {
 624                 int ret;
 625
 626                 ret = lxc_terminal_peer_proxy_alloc(terminal, sockfd);
 627                 if (ret < 0)
 628                         goto out;
 629
 630                 ptxfd = terminal->proxy.ptx;
 631                 goto out;
 632         }
 633
 634         if (*ttyreq > 0) {
 635                 if ((size_t)*ttyreq > ttys->max)
 636                         goto out;
 637
 638                 if (ttys->tty[*ttyreq - 1].busy >= 0)
 639                         goto out;
 640
 641                 /* The requested tty is available. */
 642                 ttynum = *ttyreq;
 643                 goto out_tty;
 644         }
 645
 646         /* Search for next available tty, fixup index tty1 => [0]. */
 647         for (ttynum = 1; ttynum <= ttys->max && ttys->tty[ttynum - 1].busy >= 0; ttynum++) {
 648                 ;
 649         }
 650
 651         /* We didn't find any available slot for tty. */
 652         if (ttynum > ttys->max)
 653                 goto out;
 654
 655         *ttyreq = (int)ttynum;
 656
 657 out_tty:
 658         ttys->tty[ttynum - 1].busy = sockfd;
 659         ptxfd = ttys->tty[ttynum - 1].ptx;
 660
 661 out:
 662         return ptxfd;
 663 }
 664
 665 void lxc_terminal_free(struct lxc_conf *conf, int fd)
 666 {
 667         struct lxc_tty_info *ttys = &conf->ttys;
 668         struct lxc_terminal *terminal = &conf->console;
 669
 670         for (size_t i = 0; i < ttys->max; i++)
 671                 if (ttys->tty[i].busy == fd)
 672                         ttys->tty[i].busy = -1;
 673
 674         if (terminal->proxy.busy != fd)
 675                 return;
 676
 677         lxc_mainloop_del_handler(terminal->descr, terminal->proxy.pty);
 678         lxc_terminal_peer_proxy_free(terminal);
 679 }
 680
 681 static int lxc_terminal_peer_default(struct lxc_terminal *terminal)
 682 {
 683         struct lxc_terminal_state *ts;
 684         const char *path;
 685         int ret = 0;
 686
 687         if (terminal->path)
 688                 path = terminal->path;
 689         else
 690                 path = "/dev/tty";
 691
 692         terminal->peer = lxc_unpriv(open(path, O_RDWR | O_CLOEXEC));
 693         if (terminal->peer < 0) {
 694                 if (!terminal->path) {
 695                         errno = ENODEV;
 696                         SYSDEBUG("The process does not have a controlling terminal");
 697                         goto on_succes;
 698                 }
 699
 700                 SYSERROR("Failed to open proxy terminal \"%s\"", path);
 701                 return -ENOTTY;
 702         }
 703         DEBUG("Using terminal \"%s\" as proxy", path);
 704
 705         if (!isatty(terminal->peer)) {
 706                 ERROR("File descriptor for \"%s\" does not refer to a terminal", path);
 707                 goto on_error_free_tios;
 708         }
 709
 710         ts = lxc_terminal_signal_init(terminal->peer, terminal->ptx);
 711         terminal->tty_state = ts;
 712         if (!ts) {
 713                 WARN("Failed to install signal handler");
 714                 goto on_error_free_tios;
 715         }
 716
 717         lxc_terminal_winsz(terminal->peer, terminal->ptx);
 718
 719         terminal->tios = malloc(sizeof(*terminal->tios));
 720         if (!terminal->tios)
 721                 goto on_error_free_tios;
 722
 723         ret = lxc_setup_tios(terminal->peer, terminal->tios);
 724         if (ret < 0)
 725                 goto on_error_close_peer;
 726         else
 727                 goto on_succes;
 728
 729 on_error_free_tios:
 730         free(terminal->tios);
 731         terminal->tios = NULL;
 732
 733 on_error_close_peer:
 734         close(terminal->peer);
 735         terminal->peer = -1;
 736         ret = -ENOTTY;
 737
 738 on_succes:
 739         return ret;
 740 }
 741
 742 int lxc_terminal_write_ringbuffer(struct lxc_terminal *terminal)
 743 {
 744         char *r_addr;
 745         ssize_t ret;
 746         uint64_t used;
 747         struct lxc_ringbuf *buf = &terminal->ringbuf;
 748
 749         /* There's not log file where we can dump the ringbuffer to. */
 750         if (terminal->log_fd < 0)
 751                 return 0;
 752
 753         used = lxc_ringbuf_used(buf);
 754         if (used == 0)
 755                 return 0;
 756
 757         ret = lxc_terminal_truncate_log_file(terminal);
 758         if (ret < 0)
 759                 return ret;
 760
 761         /* Write as much as we can without exceeding the limit. */
 762         if (terminal->log_size < used)
 763                 used = terminal->log_size;
 764
 765         r_addr = lxc_ringbuf_get_read_addr(buf);
 766         ret = lxc_write_nointr(terminal->log_fd, r_addr, used);
 767         if (ret < 0)
 768                 return -EIO;
 769
 770         return 0;
 771 }
 772
 773 void lxc_terminal_delete(struct lxc_terminal *terminal)
 774 {
 775         int ret;
 776
 777         ret = lxc_terminal_write_ringbuffer(terminal);
 778         if (ret < 0)
 779                 WARN("Failed to write terminal log to disk");
 780
 781         if (terminal->tios && terminal->peer >= 0) {
 782                 ret = tcsetattr(terminal->peer, TCSAFLUSH, terminal->tios);
 783                 if (ret < 0)
 784                         SYSWARN("Failed to set old terminal settings");
 785         }
 786         free(terminal->tios);
 787         terminal->tios = NULL;
 788
 789         if (terminal->peer >= 0)
 790                 close(terminal->peer);
 791         terminal->peer = -1;
 792
 793         if (terminal->ptx >= 0)
 794                 close(terminal->ptx);
 795         terminal->ptx = -1;
 796
 797         if (terminal->pty >= 0)
 798                 close(terminal->pty);
 799         terminal->pty = -1;
 800
 801         terminal->pty_nr = -1;
 802
 803         if (terminal->log_fd >= 0)
 804                 close(terminal->log_fd);
 805         terminal->log_fd = -1;
 806 }
 807
 808 /**
 809  * Note that this function needs to run before the mainloop starts. Since we
 810  * register a handler for the terminal's ptxfd when we create the mainloop
 811  * the terminal handler needs to see an allocated ringbuffer.
 812  */
 813 static int lxc_terminal_create_ringbuf(struct lxc_terminal *terminal)
 814 {
 815         int ret;
 816         struct lxc_ringbuf *buf = &terminal->ringbuf;
 817         uint64_t size = terminal->buffer_size;
 818
 819         /* no ringbuffer previously allocated and no ringbuffer requested */
 820         if (!buf->addr && size <= 0)
 821                 return 0;
 822
 823         /* ringbuffer allocated but no new ringbuffer requested */
 824         if (buf->addr && size <= 0) {
 825                 lxc_ringbuf_release(buf);
 826                 buf->addr = NULL;
 827                 buf->r_off = 0;
 828                 buf->w_off = 0;
 829                 buf->size = 0;
 830                 TRACE("Deallocated terminal ringbuffer");
 831                 return 0;
 832         }
 833
 834         if (size <= 0)
 835                 return 0;
 836
 837         /* check wether the requested size for the ringbuffer has changed */
 838         if (buf->addr && buf->size != size) {
 839                 TRACE("Terminal ringbuffer size changed from %" PRIu64
 840                       " to %" PRIu64 " bytes. Deallocating terminal ringbuffer",
 841                       buf->size, size);
 842                 lxc_ringbuf_release(buf);
 843         }
 844
 845         ret = lxc_ringbuf_create(buf, size);
 846         if (ret < 0) {
 847                 ERROR("Failed to setup %" PRIu64 " byte terminal ringbuffer", size);
 848                 return -1;
 849         }
 850
 851         TRACE("Allocated %" PRIu64 " byte terminal ringbuffer", size);
 852         return 0;
 853 }
 854
 855 /**
 856  * This is the terminal log file. Please note that the terminal log file is
 857  * (implementation wise not content wise) independent of the terminal ringbuffer.
 858  */
 859 int lxc_terminal_create_log_file(struct lxc_terminal *terminal)
 860 {
 861         if (!terminal->log_path)
 862                 return 0;
 863
 864         terminal->log_fd = lxc_unpriv(open(terminal->log_path, O_CLOEXEC | O_RDWR | O_CREAT | O_APPEND, 0600));
 865         if (terminal->log_fd < 0) {
 866                 SYSERROR("Failed to open terminal log file \"%s\"", terminal->log_path);
 867                 return -1;
 868         }
 869
 870         DEBUG("Using \"%s\" as terminal log file", terminal->log_path);
 871         return 0;
 872 }
 873
 874 static int lxc_terminal_map_ids(struct lxc_conf *c, struct lxc_terminal *terminal)
 875 {
 876         int ret;
 877
 878         if (list_empty(&c->id_map))
 879                 return 0;
 880
 881         if (is_empty_string(terminal->name) && terminal->pty < 0)
 882                 return 0;
 883
 884         if (terminal->pty >= 0)
 885                 ret = userns_exec_mapped_root(NULL, terminal->pty, c);
 886         else
 887                 ret = userns_exec_mapped_root(terminal->name, -EBADF, c);
 888         if (ret < 0)
 889                 return log_error(-1, "Failed to chown terminal %d(%s)", terminal->pty,
 890                                  !is_empty_string(terminal->name) ? terminal->name : "(null)");
 891
 892         TRACE("Chowned terminal %d(%s)", terminal->pty,
 893               !is_empty_string(terminal->name) ? terminal->name : "(null)");
 894
 895         return 0;
 896 }
 897
 898 static int lxc_terminal_create_foreign(struct lxc_conf *conf, struct lxc_terminal *terminal)
 899 {
 900         int ret;
 901
 902         ret = openpty(&terminal->ptx, &terminal->pty, NULL, NULL, NULL);
 903         if (ret < 0) {
 904                 SYSERROR("Failed to open terminal");
 905                 return -1;
 906         }
 907
 908         ret = lxc_terminal_map_ids(conf, terminal);
 909         if (ret < 0) {
 910                 SYSERROR("Failed to change ownership of terminal multiplexer device");
 911                 goto err;
 912         }
 913
 914         ret = ttyname_r(terminal->pty, terminal->name, sizeof(terminal->name));
 915         if (ret < 0) {
 916                 SYSERROR("Failed to retrieve name of terminal pty");
 917                 goto err;
 918         }
 919
 920         ret = fd_cloexec(terminal->ptx, true);
 921         if (ret < 0) {
 922                 SYSERROR("Failed to set FD_CLOEXEC flag on terminal ptx");
 923                 goto err;
 924         }
 925
 926         ret = fd_cloexec(terminal->pty, true);
 927         if (ret < 0) {
 928                 SYSERROR("Failed to set FD_CLOEXEC flag on terminal pty");
 929                 goto err;
 930         }
 931
 932         ret = lxc_terminal_peer_default(terminal);
 933         if (ret < 0) {
 934                 ERROR("Failed to allocate proxy terminal");
 935                 goto err;
 936         }
 937
 938         return 0;
 939
 940 err:
 941         lxc_terminal_delete(terminal);
 942         return -ENODEV;
 943 }
 944
 945 int lxc_devpts_terminal(int devpts_fd, int *ret_ptx, int *ret_pty,
 946                         int *ret_pty_nr, bool require_tiocgptpeer)
 947 {
 948         __do_close int fd_devpts = -EBADF, fd_ptx = -EBADF,
 949                        fd_opath_pty = -EBADF, fd_pty = -EBADF;
 950         int pty_nr = -1;
 951         int ret;
 952
 953         /*
 954          * When we aren't told what devpts instance to allocate from we assume
 955          * it is the one in the caller's mount namespace.
 956          * This poses a slight complication, a lot of distros will change
 957          * permissions on /dev/ptmx so it can be opened by unprivileged users
 958          * but will not change permissions on /dev/pts/ptmx itself. In
 959          * addition, /dev/ptmx can either be a symlink, a bind-mount, or a
 960          * separate device node. So we need to allow for fairly lax lookup.
 961          */
 962         if (devpts_fd < 0)
 963                 fd_ptx = open_at(-EBADF, "/dev/ptmx", PROTECT_OPEN_RW & ~O_NOFOLLOW,
 964                                  PROTECT_LOOKUP_ABSOLUTE_XDEV_SYMLINKS, 0);
 965         else
 966                 fd_ptx = open_beneath(devpts_fd, "ptmx", O_RDWR | O_NOCTTY | O_CLOEXEC);
 967         if (fd_ptx < 0) {
 968                 if (errno == ENOSPC)
 969                         return systrace("Exceeded number of allocatable terminals");
 970
 971                 return syserror("Failed to open terminal multiplexer device");
 972         }
 973
 974         if (devpts_fd < 0) {
 975                 fd_devpts = open_at(-EBADF, "/dev/pts", PROTECT_OPATH_DIRECTORY,
 976                                     PROTECT_LOOKUP_ABSOLUTE_XDEV, 0);
 977                 if (fd_devpts < 0)
 978                         return syserror("Failed to open devpts instance");
 979
 980                 if (!same_device(fd_devpts, "ptmx", fd_ptx, ""))
 981                         return syserror("The acquired ptmx devices don't match");
 982                 devpts_fd = fd_devpts;
 983         }
 984
 985         ret = unlockpt(fd_ptx);
 986         if (ret < 0)
 987                 return syswarn_set(-ENODEV, "Failed to unlock multiplexer device device");
 988
 989         fd_pty = ioctl(fd_ptx, TIOCGPTPEER, O_RDWR | O_NOCTTY | O_CLOEXEC);
 990         if (fd_pty < 0) {
 991                 switch (errno) {
 992                 case ENOTTY:
 993                         SYSTRACE("Pure fd-based terminal allocation not possible");
 994                         break;
 995                 case ENOSPC:
 996                         SYSTRACE("Exceeded number of allocatable terminals");
 997                         break;
 998                 default:
 999                         SYSWARN("Failed to allocate new pty device");
1000                         return -errno;
1001                 }
1002
1003                 /* The caller tells us that they trust the devpts instance. */
1004                 if (require_tiocgptpeer)
1005                         return ret_errno(ENODEV);
1006         }
1007
1008         ret = ioctl(fd_ptx, TIOCGPTN, &pty_nr);
1009         if (ret)
1010                 return syswarn_set(-ENODEV, "Failed to retrieve name of terminal pty");
1011
1012         if (fd_pty < 0) {
1013                 /*
1014                  * If we end up it means that TIOCGPTPEER isn't supported but
1015                  * the caller told us they trust the devpts instance so we use
1016                  * the pty nr to open the pty side.
1017                  */
1018                 fd_pty = open_at(devpts_fd, fdstr(pty_nr), PROTECT_OPEN_RW,
1019                                  PROTECT_LOOKUP_ABSOLUTE_XDEV, 0);
1020                 if (fd_pty < 0)
1021                         return syswarn_set(-ENODEV, "Failed to open terminal pty fd by path %d/%d",
1022                                            devpts_fd, pty_nr);
1023         } else {
1024                 fd_opath_pty = open_at(devpts_fd, fdstr(pty_nr), PROTECT_OPATH_FILE,
1025                                        PROTECT_LOOKUP_ABSOLUTE_XDEV, 0);
1026                 if (fd_opath_pty < 0)
1027                         return syswarn_set(-ENODEV, "Failed to open terminal pty fd by path %d/%d",
1028                                            devpts_fd, pty_nr);
1029
1030                 if (!same_file_lax(fd_pty, fd_opath_pty))
1031                         return syswarn_set(-ENODEV, "Terminal file descriptor changed");
1032         }
1033
1034         *ret_ptx = move_fd(fd_ptx);
1035         *ret_pty = move_fd(fd_pty);
1036         *ret_pty_nr = pty_nr;
1037         return 0;
1038 }
1039
1040 int lxc_terminal_parent(struct lxc_conf *conf)
1041 {
1042         struct lxc_terminal *console = &conf->console;
1043         int ret;
1044
1045         if (!wants_console(&conf->console))
1046                 return 0;
1047
1048         /* Allocate console from the container's devpts. */
1049         if (conf->pty_max > 1)
1050                 return 0;
1051
1052         /* Allocate console for the container from the host's devpts. */
1053         ret = lxc_devpts_terminal(-EBADF, &console->ptx, &console->pty,
1054                                   &console->pty_nr, false);
1055         if (ret < 0)
1056                 return syserror("Failed to allocate console");
1057
1058         ret = strnprintf(console->name, sizeof(console->name),
1059                          "/dev/pts/%d", console->pty_nr);
1060         if (ret < 0)
1061                 return syserror("Failed to create console path");
1062
1063         return lxc_terminal_map_ids(conf, &conf->console);
1064 }
1065
1066 static int lxc_terminal_create_native(const char *name, const char *lxcpath,
1067                                       struct lxc_terminal *terminal)
1068 {
1069         __do_close int devpts_fd = -EBADF;
1070         int ret;
1071
1072         devpts_fd = lxc_cmd_get_devpts_fd(name, lxcpath);
1073         if (devpts_fd < 0)
1074                 return sysinfo("Failed to receive devpts fd");
1075
1076         ret = lxc_devpts_terminal(devpts_fd, &terminal->ptx, &terminal->pty,
1077                                   &terminal->pty_nr, true);
1078         if (ret < 0)
1079                 return ret;
1080
1081         ret = strnprintf(terminal->name, sizeof(terminal->name),
1082                          "/dev/pts/%d", terminal->pty_nr);
1083         if (ret < 0)
1084                 return syserror("Failed to create path");
1085
1086         ret = lxc_terminal_peer_default(terminal);
1087         if (ret < 0) {
1088                 lxc_terminal_delete(terminal);
1089                 return syswarn_set(-ENODEV, "Failed to allocate proxy terminal");
1090         }
1091
1092         return 0;
1093 }
1094
1095 int lxc_terminal_create(const char *name, const char *lxcpath,
1096                         struct lxc_conf *conf, struct lxc_terminal *terminal)
1097 {
1098         if (!lxc_terminal_create_native(name, lxcpath, terminal))
1099                 return 0;
1100
1101         return lxc_terminal_create_foreign(conf, terminal);
1102 }
1103
1104 int lxc_terminal_setup(struct lxc_conf *conf)
1105 {
1106         int ret;
1107         struct lxc_terminal *terminal = &conf->console;
1108
1109         if (terminal->path && strequal(terminal->path, "none"))
1110                 return log_info(0, "No terminal requested");
1111
1112         ret = lxc_terminal_peer_default(terminal);
1113         if (ret < 0)
1114                 goto err;
1115
1116         ret = lxc_terminal_create_log_file(terminal);
1117         if (ret < 0)
1118                 goto err;
1119
1120         ret = lxc_terminal_create_ringbuf(terminal);
1121         if (ret < 0)
1122                 goto err;
1123
1124         return 0;
1125
1126 err:
1127         lxc_terminal_delete(terminal);
1128         return -ENODEV;
1129 }
1130
1131 static bool __terminal_dup2(int duplicate, int original)
1132 {
1133         int ret;
1134
1135         if (!isatty(original))
1136                 return true;
1137
1138         ret = dup2(duplicate, original);
1139         if (ret < 0) {
1140                 SYSERROR("Failed to dup2(%d, %d)", duplicate, original);
1141                 return false;
1142         }
1143
1144         return true;
1145 }
1146
1147 int lxc_terminal_set_stdfds(int fd)
1148 {
1149         int i;
1150
1151         if (fd < 0)
1152                 return 0;
1153
1154         for (i = 0; i < 3; i++)
1155                 if (!__terminal_dup2(fd, (int[]){STDIN_FILENO, STDOUT_FILENO,
1156                                                  STDERR_FILENO}[i]))
1157                         return -1;
1158
1159         return 0;
1160 }
1161
1162 int lxc_terminal_stdin_cb(int fd, uint32_t events, void *cbdata,
1163                           struct lxc_async_descr *descr)
1164 {
1165         int ret;
1166         char c;
1167         struct lxc_terminal_state *ts = cbdata;
1168
1169         if (fd != ts->stdinfd)
1170                 return LXC_MAINLOOP_CLOSE;
1171
1172         ret = lxc_read_nointr(ts->stdinfd, &c, 1);
1173         if (ret <= 0)
1174                 return LXC_MAINLOOP_CLOSE;
1175
1176         if (ts->escape >= 1) {
1177                 /* we want to exit the terminal with Ctrl+a q */
1178                 if (c == ts->escape && !ts->saw_escape) {
1179                         ts->saw_escape = 1;
1180                         return LXC_MAINLOOP_CONTINUE;
1181                 }
1182
1183                 if (c == 'q' && ts->saw_escape)
1184                         return LXC_MAINLOOP_CLOSE;
1185
1186                 ts->saw_escape = 0;
1187         }
1188
1189         ret = lxc_write_nointr(ts->ptxfd, &c, 1);
1190         if (ret <= 0)
1191                 return LXC_MAINLOOP_CLOSE;
1192
1193         return LXC_MAINLOOP_CONTINUE;
1194 }
1195
1196 int lxc_terminal_ptx_cb(int fd, uint32_t events, void *cbdata,
1197                            struct lxc_async_descr *descr)
1198 {
1199         int r, w;
1200         char buf[LXC_TERMINAL_BUFFER_SIZE];
1201         struct lxc_terminal_state *ts = cbdata;
1202
1203         if (fd != ts->ptxfd)
1204                 return LXC_MAINLOOP_CLOSE;
1205
1206         r = lxc_read_nointr(fd, buf, sizeof(buf));
1207         if (r <= 0)
1208                 return LXC_MAINLOOP_CLOSE;
1209
1210         w = lxc_write_nointr(ts->stdoutfd, buf, r);
1211         if (w <= 0 || w != r)
1212                 return LXC_MAINLOOP_CLOSE;
1213
1214         return LXC_MAINLOOP_CONTINUE;
1215 }
1216
1217 int lxc_terminal_getfd(struct lxc_container *c, int *ttynum, int *ptxfd)
1218 {
1219         return lxc_cmd_get_tty_fd(c->name, ttynum, ptxfd, c->config_path);
1220 }
1221
1222 int lxc_console(struct lxc_container *c, int ttynum,
1223                 int stdinfd, int stdoutfd, int stderrfd,
1224                 int escape)
1225 {
1226         int ptxfd, ret, ttyfd;
1227         struct lxc_async_descr descr;
1228         struct termios oldtios;
1229         struct lxc_terminal_state *ts;
1230         struct lxc_terminal terminal = {
1231                 .tty_state = NULL,
1232         };
1233         int istty = 0;
1234
1235         ttyfd = lxc_cmd_get_tty_fd(c->name, &ttynum, &ptxfd, c->config_path);
1236         if (ttyfd < 0)
1237                 return -1;
1238
1239         ret = setsid();
1240         if (ret < 0)
1241                 TRACE("Process is already group leader");
1242
1243         ts = lxc_terminal_signal_init(stdinfd, ptxfd);
1244         if (!ts) {
1245                 ret = -1;
1246                 goto close_fds;
1247         }
1248         terminal.tty_state = ts;
1249         ts->escape = escape;
1250         ts->stdoutfd = stdoutfd;
1251
1252         istty = isatty(stdinfd);
1253         if (istty) {
1254                 lxc_terminal_winsz(stdinfd, ptxfd);
1255                 lxc_terminal_winsz(ts->stdinfd, ts->ptxfd);
1256         } else {
1257                 INFO("File descriptor %d does not refer to a terminal", stdinfd);
1258         }
1259
1260         ret = lxc_mainloop_open(&descr);
1261         if (ret) {
1262                 ERROR("Failed to create mainloop");
1263                 goto sigwinch_fini;
1264         }
1265
1266         if (ts->sigfd != -1) {
1267                 ret = lxc_mainloop_add_handler(&descr, ts->sigfd,
1268                                                lxc_terminal_signalfd_cb,
1269                                                default_cleanup_handler,
1270                                                ts, "lxc_terminal_signalfd_cb");
1271                 if (ret < 0) {
1272                         ERROR("Failed to add signal handler to mainloop");
1273                         goto close_mainloop;
1274                 }
1275         }
1276
1277         ret = lxc_mainloop_add_handler(&descr, ts->stdinfd,
1278                                        lxc_terminal_stdin_cb,
1279                                        default_cleanup_handler,
1280                                        ts, "lxc_terminal_stdin_cb");
1281         if (ret < 0) {
1282                 ERROR("Failed to add stdin handler");
1283                 goto close_mainloop;
1284         }
1285
1286         ret = lxc_mainloop_add_handler(&descr, ts->ptxfd,
1287                                        lxc_terminal_ptx_cb,
1288                                        default_cleanup_handler,
1289                                        ts, "lxc_terminal_ptx_cb");
1290         if (ret < 0) {
1291                 ERROR("Failed to add ptx handler");
1292                 goto close_mainloop;
1293         }
1294
1295         if (ts->escape >= 1) {
1296                 fprintf(stderr,
1297                         "\n"
1298                         "Connected to tty %1$d\n"
1299                         "Type <Ctrl+%2$c q> to exit the console, "
1300                         "<Ctrl+%2$c Ctrl+%2$c> to enter Ctrl+%2$c itself\n",
1301                         ttynum, 'a' + escape - 1);
1302         }
1303
1304         if (istty) {
1305                 ret = lxc_setup_tios(stdinfd, &oldtios);
1306                 if (ret < 0)
1307                         goto close_mainloop;
1308         }
1309
1310         ret = lxc_mainloop(&descr, -1);
1311         if (ret < 0) {
1312                 ERROR("The mainloop returned an error");
1313                 goto restore_tios;
1314         }
1315
1316         ret = 0;
1317
1318 restore_tios:
1319         if (istty) {
1320                 istty = tcsetattr(stdinfd, TCSAFLUSH, &oldtios);
1321                 if (istty < 0)
1322                         SYSWARN("Failed to restore terminal properties");
1323         }
1324
1325 close_mainloop:
1326         lxc_mainloop_close(&descr);
1327
1328 sigwinch_fini:
1329         lxc_terminal_signal_fini(&terminal);
1330
1331 close_fds:
1332         close(ptxfd);
1333         close(ttyfd);
1334
1335         return ret;
1336 }
1337
1338 int lxc_make_controlling_terminal(int fd)
1339 {
1340         int ret;
1341
1342         setsid();
1343
1344         ret = ioctl(fd, TIOCSCTTY, (char *)NULL);
1345         if (ret < 0)
1346                 return -1;
1347
1348         return 0;
1349 }
1350
1351 int lxc_terminal_prepare_login(int fd)
1352 {
1353         int ret;
1354
1355         ret = lxc_make_controlling_terminal(fd);
1356         if (ret < 0)
1357                 return -1;
1358
1359         ret = lxc_terminal_set_stdfds(fd);
1360         if (ret < 0)
1361                 return -1;
1362
1363         if (fd > STDERR_FILENO)
1364                 close(fd);
1365
1366         return 0;
1367 }
1368
1369 void lxc_terminal_info_init(struct lxc_terminal_info *terminal)
1370 {
1371         terminal->name[0] = '\0';
1372         terminal->ptx = -EBADF;
1373         terminal->pty = -EBADF;
1374         terminal->busy = -1;
1375 }
1376
1377 void lxc_terminal_init(struct lxc_terminal *terminal)
1378 {
1379         memset(terminal, 0, sizeof(*terminal));
1380         terminal->pty_nr = -1;
1381         terminal->pty = -EBADF;
1382         terminal->ptx = -EBADF;
1383         terminal->peer = -EBADF;
1384         terminal->log_fd = -EBADF;
1385         lxc_terminal_info_init(&terminal->proxy);
1386 }
1387
1388 void lxc_terminal_conf_free(struct lxc_terminal *terminal)
1389 {
1390         free(terminal->log_path);
1391         free(terminal->path);
1392         if (terminal->buffer_size > 0 && terminal->ringbuf.addr)
1393                 lxc_ringbuf_release(&terminal->ringbuf);
1394         lxc_terminal_signal_fini(terminal);
1395 }