chiark / gitweb /
cryptsetup: accept both "read-only" and "readonly" spellings
[elogind.git] / src / nspawn / nspawn.c
index 244ebb83425faa00010c2cb104fe80c965284ca1..4c8737132b180747f6b14493cb6955704fbb1583 100644 (file)
@@ -55,6 +55,8 @@
 #include "loopback-setup.h"
 #include "sd-id128.h"
 #include "dev-setup.h"
+#include "fdset.h"
+#include "build.h"
 
 typedef enum LinkJournal {
         LINK_NO,
@@ -94,13 +96,16 @@ static uint64_t arg_retain =
         (1ULL << CAP_SYS_PTRACE) |
         (1ULL << CAP_SYS_TTY_CONFIG) |
         (1ULL << CAP_SYS_RESOURCE) |
-        (1ULL << CAP_SYS_BOOT);
+        (1ULL << CAP_SYS_BOOT) |
+        (1ULL << CAP_AUDIT_WRITE) |
+        (1ULL << CAP_AUDIT_CONTROL);
 
 static int help(void) {
 
         printf("%s [OPTIONS...] [PATH] [ARGUMENTS...]\n\n"
                "Spawn a minimal namespace container for debugging, testing and building.\n\n"
                "  -h --help               Show this help\n"
+               "  --version               Print version string\n"
                "  -D --directory=NAME     Root directory for the container\n"
                "  -b --boot               Boot up full system (i.e. invoke init)\n"
                "  -u --user=USER          Run the command under specified user or uid\n"
@@ -119,7 +124,8 @@ static int help(void) {
 static int parse_argv(int argc, char *argv[]) {
 
         enum {
-                ARG_PRIVATE_NETWORK = 0x100,
+                ARG_VERSION = 0x100,
+                ARG_PRIVATE_NETWORK,
                 ARG_UUID,
                 ARG_READ_ONLY,
                 ARG_CAPABILITY,
@@ -128,6 +134,7 @@ static int parse_argv(int argc, char *argv[]) {
 
         static const struct option options[] = {
                 { "help",            no_argument,       NULL, 'h'                 },
+                { "version",         no_argument,       NULL, ARG_VERSION         },
                 { "directory",       required_argument, NULL, 'D'                 },
                 { "user",            required_argument, NULL, 'u'                 },
                 { "controllers",     required_argument, NULL, 'C'                 },
@@ -153,6 +160,11 @@ static int parse_argv(int argc, char *argv[]) {
                         help();
                         return 0;
 
+                case ARG_VERSION:
+                        puts(PACKAGE_STRING);
+                        puts(SYSTEMD_FEATURES);
+                        return 0;
+
                 case 'D':
                         free(arg_directory);
                         arg_directory = canonicalize_file_name(optarg);
@@ -816,13 +828,18 @@ static int is_os_tree(const char *path) {
         return r < 0 ? 0 : 1;
 }
 
-static int process_pty(int master, sigset_t *mask) {
+static int process_pty(int master, pid_t pid, sigset_t *mask) {
 
         char in_buffer[LINE_MAX], out_buffer[LINE_MAX];
         size_t in_buffer_full = 0, out_buffer_full = 0;
         struct epoll_event stdin_ev, stdout_ev, master_ev, signal_ev;
         bool stdin_readable = false, stdout_writable = false, master_readable = false, master_writable = false;
         int ep = -1, signal_fd = -1, r;
+        bool tried_orderly_shutdown = false;
+
+        assert(master >= 0);
+        assert(pid > 0);
+        assert(mask);
 
         fd_nonblock(STDIN_FILENO, 1);
         fd_nonblock(STDOUT_FILENO, 1);
@@ -842,9 +859,19 @@ static int process_pty(int master, sigset_t *mask) {
                 goto finish;
         }
 
-        zero(stdin_ev);
-        stdin_ev.events = EPOLLIN|EPOLLET;
-        stdin_ev.data.fd = STDIN_FILENO;
+        /* We read from STDIN only if this is actually a TTY,
+         * otherwise we assume non-interactivity. */
+        if (isatty(STDIN_FILENO)) {
+                zero(stdin_ev);
+                stdin_ev.events = EPOLLIN|EPOLLET;
+                stdin_ev.data.fd = STDIN_FILENO;
+
+                if (epoll_ctl(ep, EPOLL_CTL_ADD, STDIN_FILENO, &stdin_ev) < 0) {
+                        log_error("Failed to register STDIN in epoll: %m");
+                        r = -errno;
+                        goto finish;
+                }
+        }
 
         zero(stdout_ev);
         stdout_ev.events = EPOLLOUT|EPOLLET;
@@ -858,11 +885,19 @@ static int process_pty(int master, sigset_t *mask) {
         signal_ev.events = EPOLLIN;
         signal_ev.data.fd = signal_fd;
 
-        if (epoll_ctl(ep, EPOLL_CTL_ADD, STDIN_FILENO, &stdin_ev) < 0 ||
-            epoll_ctl(ep, EPOLL_CTL_ADD, STDOUT_FILENO, &stdout_ev) < 0 ||
-            epoll_ctl(ep, EPOLL_CTL_ADD, master, &master_ev) < 0 ||
+        if (epoll_ctl(ep, EPOLL_CTL_ADD, STDOUT_FILENO, &stdout_ev) < 0) {
+                if (errno != EPERM) {
+                        log_error("Failed to register stdout in epoll: %m");
+                        r = -errno;
+                        goto finish;
+                }
+                /* stdout without epoll support. Likely redirected to regular file. */
+                stdout_writable = true;
+        }
+
+        if (epoll_ctl(ep, EPOLL_CTL_ADD, master, &master_ev) < 0 ||
             epoll_ctl(ep, EPOLL_CTL_ADD, signal_fd, &signal_ev) < 0) {
-                log_error("Failed to regiser fds in epoll: %m");
+                log_error("Failed to register fds in epoll: %m");
                 r = -errno;
                 goto finish;
         }
@@ -930,6 +965,14 @@ static int process_pty(int master, sigset_t *mask) {
                                                 /* The window size changed, let's forward that. */
                                                 if (ioctl(STDIN_FILENO, TIOCGWINSZ, &ws) >= 0)
                                                         ioctl(master, TIOCSWINSZ, &ws);
+                                        } else if (sfsi.ssi_signo == SIGTERM && arg_boot && !tried_orderly_shutdown) {
+
+                                                log_info("Trying to halt container. Send SIGTERM again to trigger immediate termination.");
+
+                                                /* This only works for systemd... */
+                                                tried_orderly_shutdown = true;
+                                                kill(pid, SIGRTMIN+3);
+
                                         } else {
                                                 r = 0;
                                                 goto finish;
@@ -1032,13 +1075,14 @@ int main(int argc, char *argv[]) {
         int r = EXIT_FAILURE, k;
         char *oldcg = NULL, *newcg = NULL;
         char **controller = NULL;
-        int master = -1;
+        int master = -1, n_fd_passed;
         const char *console = NULL;
         struct termios saved_attr, raw_attr;
         sigset_t mask;
         bool saved_attr_valid = false;
         struct winsize ws;
         int kmsg_socket_pair[2] = { -1, -1 };
+        FDSet *fds = NULL;
 
         log_parse_environment();
         log_open();
@@ -1083,6 +1127,18 @@ int main(int argc, char *argv[]) {
                 goto finish;
         }
 
+        log_close();
+        n_fd_passed = sd_listen_fds(false);
+        if (n_fd_passed > 0) {
+                k = fdset_new_listen_fds(&fds, false);
+                if (k < 0) {
+                        log_error("Failed to collect file descriptors: %s", strerror(-k));
+                        goto finish;
+                }
+        }
+        fdset_close_others(fds);
+        log_open();
+
         k = cg_get_by_pid(SYSTEMD_CGROUP_CONTROLLER, 0, &oldcg);
         if (k < 0) {
                 log_error("Failed to determine current cgroup: %s", strerror(-k));
@@ -1128,16 +1184,13 @@ int main(int argc, char *argv[]) {
                 goto finish;
         }
 
-        if (tcgetattr(STDIN_FILENO, &saved_attr) < 0) {
-                log_error("Failed to get terminal attributes: %m");
-                goto finish;
-        }
-
-        saved_attr_valid = true;
+        if (tcgetattr(STDIN_FILENO, &saved_attr) >= 0) {
+                saved_attr_valid = true;
 
-        raw_attr = saved_attr;
-        cfmakeraw(&raw_attr);
-        raw_attr.c_lflag &= ~ECHO;
+                raw_attr = saved_attr;
+                cfmakeraw(&raw_attr);
+                raw_attr.c_lflag &= ~ECHO;
+        }
 
         if (socketpair(AF_UNIX, SOCK_DGRAM|SOCK_NONBLOCK|SOCK_CLOEXEC, 0, kmsg_socket_pair) < 0) {
                 log_error("Failed to create kmsg socket pair");
@@ -1151,9 +1204,11 @@ int main(int argc, char *argv[]) {
         for (;;) {
                 siginfo_t status;
 
-                if (tcsetattr(STDIN_FILENO, TCSANOW, &raw_attr) < 0) {
-                        log_error("Failed to set terminal attributes: %m");
-                        goto finish;
+                if (saved_attr_valid) {
+                        if (tcsetattr(STDIN_FILENO, TCSANOW, &raw_attr) < 0) {
+                                log_error("Failed to set terminal attributes: %m");
+                                goto finish;
+                        }
                 }
 
                 pid = syscall(__NR_clone, SIGCHLD|CLONE_NEWIPC|CLONE_NEWNS|CLONE_NEWPID|CLONE_NEWUTS|(arg_private_network ? CLONE_NEWNET : 0), NULL);
@@ -1172,6 +1227,7 @@ int main(int argc, char *argv[]) {
                         const char *home = NULL;
                         uid_t uid = (uid_t) -1;
                         gid_t gid = (gid_t) -1;
+                        unsigned n_env = 0;
                         const char *envp[] = {
                                 "PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin",
                                 "container=systemd-nspawn", /* LXC sets container=lxc, so follow the scheme here */
@@ -1180,28 +1236,45 @@ int main(int argc, char *argv[]) {
                                 NULL, /* USER */
                                 NULL, /* LOGNAME */
                                 NULL, /* container_uuid */
+                                NULL, /* LISTEN_FDS */
+                                NULL, /* LISTEN_PID */
                                 NULL
                         };
 
                         envp[2] = strv_find_prefix(environ, "TERM=");
+                        n_env = 3;
 
                         close_nointr_nofail(master);
+                        master = -1;
 
                         close_nointr(STDIN_FILENO);
                         close_nointr(STDOUT_FILENO);
                         close_nointr(STDERR_FILENO);
 
-                        close_all_fds(&kmsg_socket_pair[1], 1);
+                        close_nointr_nofail(kmsg_socket_pair[0]);
+                        kmsg_socket_pair[0] = -1;
 
                         reset_all_signal_handlers();
 
                         assert_se(sigemptyset(&mask) == 0);
                         assert_se(sigprocmask(SIG_SETMASK, &mask, NULL) == 0);
 
-                        if (open_terminal(console, O_RDWR) != STDIN_FILENO ||
-                            dup2(STDIN_FILENO, STDOUT_FILENO) != STDOUT_FILENO ||
-                            dup2(STDIN_FILENO, STDERR_FILENO) != STDERR_FILENO)
+                        k = open_terminal(console, O_RDWR);
+                        if (k != STDIN_FILENO) {
+                                if (k >= 0) {
+                                        close_nointr_nofail(k);
+                                        k = -EINVAL;
+                                }
+
+                                log_error("Failed to open console: %s", strerror(-k));
                                 goto child_fail;
+                        }
+
+                        if (dup2(STDIN_FILENO, STDOUT_FILENO) != STDOUT_FILENO ||
+                            dup2(STDIN_FILENO, STDERR_FILENO) != STDERR_FILENO) {
+                                log_error("Failed to duplicate console: %m");
+                                goto child_fail;
+                        }
 
                         if (setsid() < 0) {
                                 log_error("setsid() failed: %m");
@@ -1248,6 +1321,7 @@ int main(int argc, char *argv[]) {
                                 goto child_fail;
 
                         close_nointr_nofail(kmsg_socket_pair[1]);
+                        kmsg_socket_pair[1] = -1;
 
                         if (setup_boot_id(arg_directory) < 0)
                                 goto child_fail;
@@ -1327,17 +1401,48 @@ int main(int argc, char *argv[]) {
                                         log_error("setreuid() failed: %m");
                                         goto child_fail;
                                 }
+                        } else {
+                                /* Reset everything fully to 0, just in case */
+
+                                if (setgroups(0, NULL) < 0) {
+                                        log_error("setgroups() failed: %m");
+                                        goto child_fail;
+                                }
+
+                                if (setresgid(0, 0, 0) < 0) {
+                                        log_error("setregid() failed: %m");
+                                        goto child_fail;
+                                }
+
+                                if (setresuid(0, 0, 0) < 0) {
+                                        log_error("setreuid() failed: %m");
+                                        goto child_fail;
+                                }
                         }
 
-                        if ((asprintf((char**)(envp + 3), "HOME=%s", home ? home: "/root") < 0) ||
-                            (asprintf((char**)(envp + 4), "USER=%s", arg_user ? arg_user : "root") < 0) ||
-                            (asprintf((char**)(envp + 5), "LOGNAME=%s", arg_user ? arg_user : "root") < 0)) {
+                        if ((asprintf((char**)(envp + n_env++), "HOME=%s", home ? home: "/root") < 0) ||
+                            (asprintf((char**)(envp + n_env++), "USER=%s", arg_user ? arg_user : "root") < 0) ||
+                            (asprintf((char**)(envp + n_env++), "LOGNAME=%s", arg_user ? arg_user : "root") < 0)) {
                                 log_oom();
                                 goto child_fail;
                         }
 
                         if (arg_uuid) {
-                                if (asprintf((char**)(envp + 6), "container_uuid=%s", arg_uuid) < 0) {
+                                if (asprintf((char**)(envp + n_env++), "container_uuid=%s", arg_uuid) < 0) {
+                                        log_oom();
+                                        goto child_fail;
+                                }
+                        }
+
+                        if (fdset_size(fds) > 0) {
+                                k = fdset_cloexec(fds, false);
+                                if (k < 0) {
+                                        log_error("Failed to unset O_CLOEXEC for file descriptors.");
+                                        goto child_fail;
+                                }
+
+                                if ((asprintf((char **)(envp + n_env++), "LISTEN_FDS=%u", n_fd_passed) < 0) ||
+                                    (asprintf((char **)(envp + n_env++), "LISTEN_PID=%lu", (unsigned long) getpid()) < 0)) {
                                         log_oom();
                                         goto child_fail;
                                 }
@@ -1376,9 +1481,11 @@ int main(int argc, char *argv[]) {
                         _exit(EXIT_FAILURE);
                 }
 
-                if (process_pty(master, &mask) < 0)
-                        goto finish;
+                fdset_free(fds);
+                fds = NULL;
 
+                if (process_pty(master, pid, &mask) < 0)
+                        goto finish;
 
                 if (saved_attr_valid)
                         tcsetattr(STDIN_FILENO, TCSANOW, &saved_attr);
@@ -1440,5 +1547,7 @@ finish:
         free(oldcg);
         free(newcg);
 
+        fdset_free(fds);
+
         return r;
 }