/
attach.c
1467 lines (1238 loc) · 36.1 KB
/
attach.c
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/*
* lxc: linux Container library
*
* (C) Copyright IBM Corp. 2007, 2008
*
* Authors:
* Daniel Lezcano <daniel.lezcano at free.fr>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#define _GNU_SOURCE
#include <errno.h>
#include <fcntl.h>
#include <grp.h>
#include <pwd.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <linux/unistd.h>
#include <sys/mount.h>
#include <sys/param.h>
#include <sys/prctl.h>
#include <sys/socket.h>
#include <sys/syscall.h>
#include <sys/wait.h>
#include <lxc/lxccontainer.h>
#ifndef HAVE_DECL_PR_CAPBSET_DROP
#define PR_CAPBSET_DROP 24
#endif
#include "af_unix.h"
#include "attach.h"
#include "caps.h"
#include "cgroup.h"
#include "commands.h"
#include "conf.h"
#include "config.h"
#include "confile.h"
#include "console.h"
#include "log.h"
#include "lsm/lsm.h"
#include "lxclock.h"
#include "lxcseccomp.h"
#include "mainloop.h"
#include "namespace.h"
#include "utils.h"
#if HAVE_SYS_PERSONALITY_H
#include <sys/personality.h>
#endif
#ifndef SOCK_CLOEXEC
#define SOCK_CLOEXEC 02000000
#endif
#ifndef MS_REC
#define MS_REC 16384
#endif
#ifndef MS_SLAVE
#define MS_SLAVE (1 << 19)
#endif
#define LXC_ATTACH_ALLOCATE_PTY 0x00000000
lxc_log_define(lxc_attach, lxc);
/* /proc/pid-to-str/status\0 = (5 + 21 + 7 + 1) */
#define __PROC_STATUS_LEN (5 + (LXC_NUMSTRLEN64) + 7 + 1)
static struct lxc_proc_context_info *lxc_proc_get_context_info(pid_t pid)
{
int ret;
bool found;
FILE *proc_file;
char proc_fn[__PROC_STATUS_LEN];
size_t line_bufsz = 0;
char *line = NULL;
struct lxc_proc_context_info *info = NULL;
/* Read capabilities. */
ret = snprintf(proc_fn, __PROC_STATUS_LEN, "/proc/%d/status", pid);
if (ret < 0 || ret >= __PROC_STATUS_LEN)
goto on_error;
proc_file = fopen(proc_fn, "r");
if (!proc_file) {
SYSERROR("Could not open %s.", proc_fn);
goto on_error;
}
info = calloc(1, sizeof(*info));
if (!info) {
SYSERROR("Could not allocate memory.");
fclose(proc_file);
return NULL;
}
found = false;
while (getline(&line, &line_bufsz, proc_file) != -1) {
ret = sscanf(line, "CapBnd: %llx", &info->capability_mask);
if (ret != EOF && ret == 1) {
found = true;
break;
}
}
free(line);
fclose(proc_file);
if (!found) {
SYSERROR("Could not read capability bounding set from %s.",
proc_fn);
errno = ENOENT;
goto on_error;
}
info->lsm_label = lsm_process_label_get(pid);
info->ns_inherited = 0;
memset(info->ns_fd, -1, sizeof(int) * LXC_NS_MAX);
return info;
on_error:
free(info);
return NULL;
}
static inline void lxc_proc_close_ns_fd(struct lxc_proc_context_info *ctx)
{
int i;
for (i = 0; i < LXC_NS_MAX; i++) {
if (ctx->ns_fd[i] < 0)
continue;
close(ctx->ns_fd[i]);
ctx->ns_fd[i] = -EBADF;
}
}
static void lxc_proc_put_context_info(struct lxc_proc_context_info *ctx)
{
free(ctx->lsm_label);
ctx->lsm_label = NULL;
if (ctx->container) {
lxc_container_put(ctx->container);
ctx->container = NULL;
}
lxc_proc_close_ns_fd(ctx);
free(ctx);
}
/**
* in_same_namespace - Check whether two processes are in the same namespace.
* @pid1 - PID of the first process.
* @pid2 - PID of the second process.
* @ns - Name of the namespace to check. Must correspond to one of the names
* for the namespaces as shown in /proc/<pid/ns/
*
* If the two processes are not in the same namespace returns an fd to the
* namespace of the second process identified by @pid2. If the two processes are
* in the same namespace returns -EINVAL, -1 if an error occurred.
*/
static int in_same_namespace(pid_t pid1, pid_t pid2, const char *ns)
{
int ns_fd1 = -1, ns_fd2 = -1, ret = -1;
struct stat ns_st1, ns_st2;
ns_fd1 = lxc_preserve_ns(pid1, ns);
if (ns_fd1 < 0) {
/* The kernel does not support this namespace. This is not an
* error.
*/
if (errno == ENOENT)
return -EINVAL;
goto out;
}
ns_fd2 = lxc_preserve_ns(pid2, ns);
if (ns_fd2 < 0)
goto out;
ret = fstat(ns_fd1, &ns_st1);
if (ret < 0)
goto out;
ret = fstat(ns_fd2, &ns_st2);
if (ret < 0)
goto out;
/* processes are in the same namespace */
ret = -EINVAL;
if ((ns_st1.st_dev == ns_st2.st_dev ) && (ns_st1.st_ino == ns_st2.st_ino))
goto out;
/* processes are in different namespaces */
ret = ns_fd2;
ns_fd2 = -1;
out:
if (ns_fd1 >= 0)
close(ns_fd1);
if (ns_fd2 >= 0)
close(ns_fd2);
return ret;
}
static int lxc_attach_to_ns(pid_t pid, struct lxc_proc_context_info *ctx)
{
int i, ret;
for (i = 0; i < LXC_NS_MAX; i++) {
if (ctx->ns_fd[i] < 0)
continue;
ret = setns(ctx->ns_fd[i], ns_info[i].clone_flag);
if (ret < 0) {
SYSERROR("Failed to attach to %s namespace of %d",
ns_info[i].proc_name, pid);
return -1;
}
DEBUG("Attached to %s namespace of %d", ns_info[i].proc_name, pid);
}
return 0;
}
static int lxc_attach_remount_sys_proc(void)
{
int ret;
ret = unshare(CLONE_NEWNS);
if (ret < 0) {
SYSERROR("Failed to unshare mount namespace.");
return -1;
}
if (detect_shared_rootfs()) {
if (mount(NULL, "/", NULL, MS_SLAVE | MS_REC, NULL)) {
SYSERROR("Failed to make / rslave.");
ERROR("Continuing...");
}
}
/* Assume /proc is always mounted, so remount it. */
ret = umount2("/proc", MNT_DETACH);
if (ret < 0) {
SYSERROR("Failed to unmount /proc.");
return -1;
}
ret = mount("none", "/proc", "proc", 0, NULL);
if (ret < 0) {
SYSERROR("Failed to remount /proc.");
return -1;
}
/* Try to umount /sys. If it's not a mount point, we'll get EINVAL, then
* we ignore it because it may not have been mounted in the first place.
*/
ret = umount2("/sys", MNT_DETACH);
if (ret < 0 && errno != EINVAL) {
SYSERROR("Failed to unmount /sys.");
return -1;
} else if (ret == 0) {
/* Remount it. */
ret = mount("none", "/sys", "sysfs", 0, NULL);
if (ret < 0) {
SYSERROR("Failed to remount /sys.");
return -1;
}
}
return 0;
}
static int lxc_attach_drop_privs(struct lxc_proc_context_info *ctx)
{
int cap, last_cap;
last_cap = lxc_caps_last_cap();
for (cap = 0; cap <= last_cap; cap++) {
if (ctx->capability_mask & (1LL << cap))
continue;
if (prctl(PR_CAPBSET_DROP, cap, 0, 0, 0)) {
SYSERROR("Failed to drop capability %d", cap);
return -1;
}
TRACE("Dropped capability %d", cap);
}
return 0;
}
static int lxc_attach_set_environment(struct lxc_proc_context_info *init_ctx,
enum lxc_attach_env_policy_t policy,
char **extra_env, char **extra_keep)
{
int ret;
struct lxc_list *iterator;
if (policy == LXC_ATTACH_CLEAR_ENV) {
int path_kept = 0;
char **extra_keep_store = NULL;
if (extra_keep) {
size_t count, i;
for (count = 0; extra_keep[count]; count++)
;
extra_keep_store = calloc(count, sizeof(char *));
if (!extra_keep_store)
return -1;
for (i = 0; i < count; i++) {
char *v = getenv(extra_keep[i]);
if (v) {
extra_keep_store[i] = strdup(v);
if (!extra_keep_store[i]) {
while (i > 0)
free(extra_keep_store[--i]);
free(extra_keep_store);
return -1;
}
if (strcmp(extra_keep[i], "PATH") == 0)
path_kept = 1;
}
}
}
if (clearenv()) {
if (extra_keep_store) {
char **p;
for (p = extra_keep_store; *p; p++)
free(*p);
free(extra_keep_store);
}
SYSERROR("Failed to clear environment");
return -1;
}
if (extra_keep_store) {
size_t i;
for (i = 0; extra_keep[i]; i++) {
if (extra_keep_store[i]) {
ret = setenv(extra_keep[i], extra_keep_store[i], 1);
if (ret < 0)
WARN("%s - Failed to set environment variable", strerror(errno));
}
free(extra_keep_store[i]);
}
free(extra_keep_store);
}
/* Always set a default path; shells and execlp tend to be fine
* without it, but there is a disturbing number of C programs
* out there that just assume that getenv("PATH") is never NULL
* and then die a painful segfault death.
*/
if (!path_kept) {
ret = setenv("PATH", "/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin", 1);
if (ret < 0)
WARN("%s - Failed to set environment variable", strerror(errno));
}
}
ret = putenv("container=lxc");
if (ret < 0) {
WARN("%s - Failed to set environment variable", strerror(errno));
return -1;
}
/* Set container environment variables.*/
if (init_ctx && init_ctx->container && init_ctx->container->lxc_conf) {
lxc_list_for_each(iterator, &init_ctx->container->lxc_conf->environment) {
char *env_tmp;
env_tmp = strdup((char *)iterator->elem);
if (!env_tmp)
return -1;
ret = putenv(env_tmp);
if (ret < 0) {
SYSERROR("Failed to set environment variable: %s", (char *)iterator->elem);
return -1;
}
}
}
/* Set extra environment variables. */
if (extra_env) {
for (; *extra_env; extra_env++) {
char *p;
/* We just assume the user knows what they are doing, so
* we don't do any checks.
*/
p = strdup(*extra_env);
if (!p)
return -1;
ret = putenv(p);
if (ret < 0)
WARN("%s - Failed to set environment variable", strerror(errno));
}
}
return 0;
}
static char *lxc_attach_getpwshell(uid_t uid)
{
int fd, ret;
pid_t pid;
int pipes[2];
FILE *pipe_f;
bool found = false;
size_t line_bufsz = 0;
char *line = NULL, *result = NULL;
/* We need to fork off a process that runs the getent program, and we
* need to capture its output, so we use a pipe for that purpose.
*/
ret = pipe2(pipes, O_CLOEXEC);
if (ret < 0)
return NULL;
pid = fork();
if (pid < 0) {
close(pipes[0]);
close(pipes[1]);
return NULL;
}
if (!pid) {
char uid_buf[32];
char *arguments[] = {
"getent",
"passwd",
uid_buf,
NULL
};
close(pipes[0]);
/* We want to capture stdout. */
ret = dup2(pipes[1], STDOUT_FILENO);
close(pipes[1]);
if (ret < 0)
exit(EXIT_FAILURE);
/* Get rid of stdin/stderr, so we try to associate it with
* /dev/null.
*/
fd = open_devnull();
if (fd < 0) {
close(STDIN_FILENO);
close(STDERR_FILENO);
} else {
(void)dup3(fd, STDIN_FILENO, O_CLOEXEC);
(void)dup3(fd, STDOUT_FILENO, O_CLOEXEC);
close(fd);
}
/* Finish argument list. */
ret = snprintf(uid_buf, sizeof(uid_buf), "%ld", (long)uid);
if (ret <= 0 || ret >= sizeof(uid_buf))
exit(EXIT_FAILURE);
/* Try to run getent program. */
(void)execvp("getent", arguments);
exit(EXIT_FAILURE);
}
close(pipes[1]);
pipe_f = fdopen(pipes[0], "r");
while (getline(&line, &line_bufsz, pipe_f) != -1) {
int i;
long value;
char *token;
char *endptr = NULL, *saveptr = NULL;
/* If we already found something, just continue to read
* until the pipe doesn't deliver any more data, but
* don't modify the existing data structure.
*/
if (found)
continue;
if (!line)
continue;
/* Trim line on the right hand side. */
for (i = strlen(line); i > 0 && (line[i - 1] == '\n' || line[i - 1] == '\r'); --i)
line[i - 1] = '\0';
/* Split into tokens: first: user name. */
token = strtok_r(line, ":", &saveptr);
if (!token)
continue;
/* next: dummy password field */
token = strtok_r(NULL, ":", &saveptr);
if (!token)
continue;
/* next: user id */
token = strtok_r(NULL, ":", &saveptr);
value = token ? strtol(token, &endptr, 10) : 0;
if (!token || !endptr || *endptr || value == LONG_MIN ||
value == LONG_MAX)
continue;
/* dummy sanity check: user id matches */
if ((uid_t)value != uid)
continue;
/* skip fields: gid, gecos, dir, go to next field 'shell' */
for (i = 0; i < 4; i++) {
token = strtok_r(NULL, ":", &saveptr);
if (!token)
continue;
}
if (!token)
continue;
free(result);
result = strdup(token);
/* Sanity check that there are no fields after that. */
token = strtok_r(NULL, ":", &saveptr);
if (token)
continue;
found = true;
}
free(line);
fclose(pipe_f);
ret = wait_for_pid(pid);
if (ret < 0) {
free(result);
return NULL;
}
if (!found) {
free(result);
return NULL;
}
return result;
}
static void lxc_attach_get_init_uidgid(uid_t *init_uid, gid_t *init_gid)
{
FILE *proc_file;
char proc_fn[__PROC_STATUS_LEN];
int ret;
char *line = NULL;
size_t line_bufsz = 0;
long value = -1;
uid_t uid = (uid_t)-1;
gid_t gid = (gid_t)-1;
ret = snprintf(proc_fn, __PROC_STATUS_LEN, "/proc/%d/status", 1);
if (ret < 0 || ret >= __PROC_STATUS_LEN)
return;
proc_file = fopen(proc_fn, "r");
if (!proc_file)
return;
while (getline(&line, &line_bufsz, proc_file) != -1) {
/* Format is: real, effective, saved set user, fs we only care
* about real uid.
*/
ret = sscanf(line, "Uid: %ld", &value);
if (ret != EOF && ret == 1) {
uid = (uid_t)value;
} else {
ret = sscanf(line, "Gid: %ld", &value);
if (ret != EOF && ret == 1)
gid = (gid_t)value;
}
if (uid != (uid_t)-1 && gid != (gid_t)-1)
break;
}
fclose(proc_file);
free(line);
/* Only override arguments if we found something. */
if (uid != (uid_t)-1)
*init_uid = uid;
if (gid != (gid_t)-1)
*init_gid = gid;
/* TODO: we should also parse supplementary groups and use
* setgroups() to set them.
*/
}
/* Help the optimizer along if it doesn't know that exit always exits. */
#define rexit(c) \
do { \
int __c = (c); \
_exit(__c); \
return __c; \
} while (0)
/* Define default options if no options are supplied by the user. */
static lxc_attach_options_t attach_static_default_options = LXC_ATTACH_OPTIONS_DEFAULT;
static bool fetch_seccomp(struct lxc_container *c,
lxc_attach_options_t *options)
{
char *path;
if (!(options->namespaces & CLONE_NEWNS) ||
!(options->attach_flags & LXC_ATTACH_LSM)) {
free(c->lxc_conf->seccomp);
c->lxc_conf->seccomp = NULL;
return true;
}
/* Remove current setting. */
if (!c->set_config_item(c, "lxc.seccomp", ""))
return false;
/* Fetch the current profile path over the cmd interface. */
path = c->get_running_config_item(c, "lxc.seccomp");
if (!path) {
INFO("Failed to get running config item for lxc.seccomp");
return true;
}
/* Copy the value into the new lxc_conf. */
if (!c->set_config_item(c, "lxc.seccomp", path)) {
free(path);
return false;
}
free(path);
/* Attempt to parse the resulting config. */
if (lxc_read_seccomp_config(c->lxc_conf) < 0) {
ERROR("Error reading seccomp policy.");
return false;
}
INFO("Retrieved seccomp policy.");
return true;
}
static signed long get_personality(const char *name, const char *lxcpath)
{
char *p;
signed long ret;
p = lxc_cmd_get_config_item(name, "lxc.arch", lxcpath);
if (!p)
return -1;
ret = lxc_config_parse_arch(p);
free(p);
return ret;
}
struct attach_clone_payload {
int ipc_socket;
int pty_fd;
lxc_attach_options_t *options;
struct lxc_proc_context_info *init_ctx;
lxc_attach_exec_t exec_function;
void *exec_payload;
};
static void lxc_put_attach_clone_payload(struct attach_clone_payload *p)
{
if (p->ipc_socket >= 0) {
close(p->ipc_socket);
p->ipc_socket = -EBADF;
}
if (p->pty_fd >= 0) {
close(p->pty_fd);
p->pty_fd = -EBADF;
}
if (p->init_ctx) {
lxc_proc_put_context_info(p->init_ctx);
p->init_ctx = NULL;
}
}
static int attach_child_main(struct attach_clone_payload *payload)
{
int fd, lsm_fd, ret;
uid_t new_uid;
gid_t new_gid;
lxc_attach_options_t* options = payload->options;
struct lxc_proc_context_info* init_ctx = payload->init_ctx;
bool needs_lsm = (options->namespaces & CLONE_NEWNS) &&
(options->attach_flags & LXC_ATTACH_LSM) &&
init_ctx->lsm_label;
/* A description of the purpose of this functionality is provided in the
* lxc-attach(1) manual page. We have to remount here and not in the
* parent process, otherwise /proc may not properly reflect the new pid
* namespace.
*/
if (!(options->namespaces & CLONE_NEWNS) &&
(options->attach_flags & LXC_ATTACH_REMOUNT_PROC_SYS)) {
ret = lxc_attach_remount_sys_proc();
if (ret < 0)
goto on_error;
TRACE("Remounted \"/proc\" and \"/sys\"");
}
/* Now perform additional attachments. */
#if HAVE_SYS_PERSONALITY_H
if (options->attach_flags & LXC_ATTACH_SET_PERSONALITY) {
long new_personality;
if (options->personality < 0)
new_personality = init_ctx->personality;
else
new_personality = options->personality;
ret = personality(new_personality);
if (ret < 0)
goto on_error;
TRACE("Set new personality");
}
#endif
if (options->attach_flags & LXC_ATTACH_DROP_CAPABILITIES) {
ret = lxc_attach_drop_privs(init_ctx);
if (ret < 0)
goto on_error;
TRACE("Dropped capabilities");
}
/* Always set the environment (specify (LXC_ATTACH_KEEP_ENV, NULL, NULL)
* if you want this to be a no-op).
*/
ret = lxc_attach_set_environment(init_ctx,
options->env_policy,
options->extra_env_vars,
options->extra_keep_env);
if (ret < 0)
goto on_error;
TRACE("Set up environment");
/* This remark only affects fully unprivileged containers:
* Receive fd for LSM security module before we set{g,u}id(). The reason
* is that on set{g,u}id() the kernel will a) make us undumpable and b)
* we will change our effective uid. This means our effective uid will
* be different from the effective uid of the process that created us
* which means that this processs no longer has capabilities in our
* namespace including CAP_SYS_PTRACE. This means we will not be able to
* read and /proc/<pid> files for the process anymore when /proc is
* mounted with hidepid={1,2}. So let's get the lsm label fd before the
* set{g,u}id().
*/
if (needs_lsm) {
ret = lxc_abstract_unix_recv_fds(payload->ipc_socket, &lsm_fd, 1, NULL, 0);
if (ret <= 0)
goto on_error;
TRACE("Received LSM label file descriptor %d from parent", lsm_fd);
}
if (options->stdin_fd > 0 && isatty(options->stdin_fd)) {
ret = lxc_make_controlling_pty(options->stdin_fd);
if (ret < 0)
goto on_error;
}
/* Set {u,g}id. */
new_uid = 0;
new_gid = 0;
/* Ignore errors, we will fall back to root in that case (/proc was not
* mounted etc.).
*/
if (options->namespaces & CLONE_NEWUSER)
lxc_attach_get_init_uidgid(&new_uid, &new_gid);
if (options->uid != (uid_t)-1)
new_uid = options->uid;
if (options->gid != (gid_t)-1)
new_gid = options->gid;
/* Try to set the {u,g}id combination. */
if (new_uid != 0 || new_gid != 0 || options->namespaces & CLONE_NEWUSER) {
ret = lxc_switch_uid_gid(new_uid, new_gid);
if (ret < 0)
goto on_error;
ret = lxc_setgroups(0, NULL);
if (ret < 0)
goto on_error;
}
if (needs_lsm) {
bool on_exec;
/* Change into our new LSM profile. */
on_exec = options->attach_flags & LXC_ATTACH_LSM_EXEC ? true : false;
ret = lsm_process_label_set_at(lsm_fd, init_ctx->lsm_label, on_exec);
close(lsm_fd);
if (ret < 0)
goto on_error;
TRACE("Set %s LSM label to \"%s\"", lsm_name(), init_ctx->lsm_label);
}
if (init_ctx->container && init_ctx->container->lxc_conf &&
init_ctx->container->lxc_conf->seccomp) {
ret = lxc_seccomp_load(init_ctx->container->lxc_conf);
if (ret < 0)
goto on_error;
TRACE("Loaded seccomp profile");
}
close(payload->ipc_socket);
payload->ipc_socket = -EBADF;
lxc_proc_put_context_info(init_ctx);
payload->init_ctx = NULL;
/* The following is done after the communication socket is shut down.
* That way, all errors that might (though unlikely) occur up until this
* point will have their messages printed to the original stderr (if
* logging is so configured) and not the fd the user supplied, if any.
*/
/* Fd handling for stdin, stdout and stderr; ignore errors here, user
* may want to make sure the fds are closed, for example.
*/
if (options->stdin_fd >= 0 && options->stdin_fd != STDIN_FILENO)
(void)dup2(options->stdin_fd, STDIN_FILENO);
if (options->stdout_fd >= 0 && options->stdout_fd != STDOUT_FILENO)
(void)dup2(options->stdout_fd, STDOUT_FILENO);
if (options->stderr_fd >= 0 && options->stderr_fd != STDERR_FILENO)
(void)dup2(options->stderr_fd, STDERR_FILENO);
/* close the old fds */
if (options->stdin_fd > STDERR_FILENO)
close(options->stdin_fd);
if (options->stdout_fd > STDERR_FILENO)
close(options->stdout_fd);
if (options->stderr_fd > STDERR_FILENO)
close(options->stderr_fd);
/* Try to remove FD_CLOEXEC flag from stdin/stdout/stderr, but also
* here, ignore errors.
*/
for (fd = STDIN_FILENO; fd <= STDERR_FILENO; fd++) {
int flags;
flags = fcntl(fd, F_GETFL);
if (flags < 0)
continue;
if ((flags & FD_CLOEXEC) == 0)
continue;
ret = fcntl(fd, F_SETFL, flags & ~FD_CLOEXEC);
if (ret < 0) {
SYSERROR("Failed to clear FD_CLOEXEC from file descriptor %d", fd);
goto on_error;
}
}
if (options->attach_flags & LXC_ATTACH_ALLOCATE_PTY) {
ret = lxc_login_pty(payload->pty_fd);
if (ret < 0) {
SYSERROR("Failed to prepare pty file descriptor %d", payload->pty_fd);
goto on_error;
}
TRACE("Prepared pty file descriptor %d", payload->pty_fd);
}
/* We're done, so we can now do whatever the user intended us to do. */
rexit(payload->exec_function(payload->exec_payload));
on_error:
lxc_put_attach_clone_payload(payload);
rexit(EXIT_FAILURE);
}
static int lxc_attach_pty(struct lxc_conf *conf, struct lxc_console *pty)
{
int ret;
lxc_pty_init(pty);
ret = lxc_pty_create(pty);
if (ret < 0) {
SYSERROR("Failed to create pty");
return -1;
}
/* Shift ttys to container. */
ret = lxc_pty_map_ids(conf, pty);
if (ret < 0) {
ERROR("Failed to shift pty");
goto on_error;
}
return 0;
on_error:
lxc_console_delete(pty);
lxc_pty_conf_free(pty);
return -1;
}
static int lxc_attach_pty_mainloop_init(struct lxc_console *pty,
struct lxc_epoll_descr *descr)
{
int ret;
ret = lxc_mainloop_open(descr);
if (ret < 0) {
ERROR("Failed to create mainloop");
return -1;
}
ret = lxc_console_mainloop_add(descr, pty);
if (ret < 0) {
ERROR("Failed to add handlers to mainloop");
lxc_mainloop_close(descr);
return -1;
}
return 0;
}
static inline void lxc_attach_pty_close_master(struct lxc_console *pty)
{
if (pty->master < 0)
return;
close(pty->master);
pty->master = -EBADF;
}
static inline void lxc_attach_pty_close_slave(struct lxc_console *pty)
{
if (pty->slave < 0)
return;
close(pty->slave);
pty->slave = -EBADF;
}
static inline void lxc_attach_pty_close_peer(struct lxc_console *pty)
{
if (pty->peer < 0)
return;
close(pty->peer);
pty->peer = -EBADF;
}
static inline void lxc_attach_pty_close_log(struct lxc_console *pty)
{
if (pty->log_fd < 0)
return;
close(pty->log_fd);