X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Fnspawn%2Fnspawn.c;h=caf1aa9bedfee1373d5aca396cbf26a1dc50d37f;hp=34a0dafa645803024956b62d016debfc17fe95e0;hb=354bfd2b166d1044eea05ac9ba1cda05c93a24bc;hpb=eb9da376d76b48585b3b63b4f91903b54f7abd36 diff --git a/src/nspawn/nspawn.c b/src/nspawn/nspawn.c index 34a0dafa6..caf1aa9be 100644 --- a/src/nspawn/nspawn.c +++ b/src/nspawn/nspawn.c @@ -40,6 +40,7 @@ #include #include #include +#include #include "sd-daemon.h" #include "sd-bus.h" @@ -61,6 +62,8 @@ #include "bus-util.h" #include "bus-error.h" #include "ptyfwd.h" +#include "bus-kernel.h" +#include "env-util.h" #ifndef TTY_GID #define TTY_GID 5 @@ -110,6 +113,7 @@ static uint64_t arg_retain = (1ULL << CAP_AUDIT_CONTROL); static char **arg_bind = NULL; static char **arg_bind_ro = NULL; +static char **arg_setenv = NULL; static int help(void) { @@ -127,11 +131,13 @@ static int help(void) { " --read-only Mount the root directory read-only\n" " --capability=CAP In addition to the default, retain specified\n" " capability\n" + " --drop-capability=CAP Drop the specified capability from the default set\n" " --link-journal=MODE Link up guest journal, one of no, auto, guest, host\n" " -j Equivalent to --link-journal=host\n" " --bind=PATH[:PATH] Bind mount a file or directory from the host into\n" " the container\n" - " --bind-ro=PATH[:PATH] Similar, but creates a read-only bind mount\n", + " --bind-ro=PATH[:PATH] Similar, but creates a read-only bind mount\n" + " --setenv=NAME=VALUE Pass an environment variable to PID 1\n", program_invocation_short_name); return 0; @@ -145,9 +151,11 @@ static int parse_argv(int argc, char *argv[]) { ARG_UUID, ARG_READ_ONLY, ARG_CAPABILITY, + ARG_DROP_CAPABILITY, ARG_LINK_JOURNAL, ARG_BIND, - ARG_BIND_RO + ARG_BIND_RO, + ARG_SETENV, }; static const struct option options[] = { @@ -160,11 +168,13 @@ static int parse_argv(int argc, char *argv[]) { { "uuid", required_argument, NULL, ARG_UUID }, { "read-only", no_argument, NULL, ARG_READ_ONLY }, { "capability", required_argument, NULL, ARG_CAPABILITY }, + { "drop-capability", required_argument, NULL, ARG_DROP_CAPABILITY }, { "link-journal", required_argument, NULL, ARG_LINK_JOURNAL }, { "bind", required_argument, NULL, ARG_BIND }, { "bind-ro", required_argument, NULL, ARG_BIND_RO }, { "machine", required_argument, NULL, 'M' }, { "slice", required_argument, NULL, 'S' }, + { "setenv", required_argument, NULL, ARG_SETENV }, {} }; @@ -189,7 +199,7 @@ static int parse_argv(int argc, char *argv[]) { free(arg_directory); arg_directory = canonicalize_file_name(optarg); if (!arg_directory) { - log_error("Failed to canonicalize root directory."); + log_error("Invalid root directory: %m"); return -ENOMEM; } @@ -243,7 +253,8 @@ static int parse_argv(int argc, char *argv[]) { arg_read_only = true; break; - case ARG_CAPABILITY: { + case ARG_CAPABILITY: + case ARG_DROP_CAPABILITY: { char *state, *word; size_t length; @@ -262,7 +273,11 @@ static int parse_argv(int argc, char *argv[]) { } free(t); - arg_retain |= 1ULL << (uint64_t) cap; + + if (c == ARG_CAPABILITY) + arg_retain |= 1ULL << (uint64_t) cap; + else + arg_retain &= ~(1ULL << (uint64_t) cap); } break; @@ -324,6 +339,23 @@ static int parse_argv(int argc, char *argv[]) { break; } + case ARG_SETENV: { + char **n; + + if (!env_assignment_is_valid(optarg)) { + log_error("Environment variable assignment '%s' is not valid.", optarg); + return -EINVAL; + } + + n = strv_env_set(arg_setenv, optarg); + if (!n) + return log_oom(); + + strv_free(arg_setenv); + arg_setenv = n; + break; + } + case '?': return -EINVAL; @@ -409,39 +441,46 @@ static int mount_binds(const char *dest, char **l, unsigned long flags) { char **x, **y; STRV_FOREACH_PAIR(x, y, l) { - _cleanup_free_ char *where = NULL; + char *where; struct stat source_st, dest_st; + int r; if (stat(*x, &source_st) < 0) { log_error("failed to stat %s: %m", *x); return -errno; } - where = strjoin(dest, "/", *y, NULL); - if (!where) - return log_oom(); - - if (stat(where, &dest_st) == 0) { + where = strappenda(dest, *y); + r = stat(where, &dest_st); + if (r == 0) { if ((source_st.st_mode & S_IFMT) != (dest_st.st_mode & S_IFMT)) { log_error("The file types of %s and %s do not match. Refusing bind mount", *x, where); return -EINVAL; } - } else { - /* Create the mount point, but be conservative -- refuse to create block - * and char devices. */ - if (S_ISDIR(source_st.st_mode)) - mkdir_p_label(where, 0755); - else if (S_ISFIFO(source_st.st_mode)) - mkfifo(where, 0644); - else if (S_ISSOCK(source_st.st_mode)) - mknod(where, 0644 | S_IFSOCK, 0); - else if (S_ISREG(source_st.st_mode)) - touch(where); - else { - log_error("Refusing to create mountpoint for file: %s", *x); - return -ENOTSUP; + } else if (errno == ENOENT) { + r = mkdir_parents_label(where, 0755); + if (r < 0) { + log_error("Failed to bind mount %s: %s", *x, strerror(-r)); + return r; } + } else { + log_error("Failed to bind mount %s: %s", *x, strerror(errno)); + return -errno; + } + /* Create the mount point, but be conservative -- refuse to create block + * and char devices. */ + if (S_ISDIR(source_st.st_mode)) + mkdir_label(where, 0755); + else if (S_ISFIFO(source_st.st_mode)) + mkfifo(where, 0644); + else if (S_ISSOCK(source_st.st_mode)) + mknod(where, 0644 | S_IFSOCK, 0); + else if (S_ISREG(source_st.st_mode)) + touch(where); + else { + log_error("Refusing to create mountpoint for file: %s", *x); + return -ENOTSUP; } if (mount(*x, where, "bind", MS_BIND, NULL) < 0) { @@ -788,14 +827,11 @@ static int setup_hostname(void) { } static int setup_journal(const char *directory) { - sd_id128_t machine_id; + sd_id128_t machine_id, this_id; _cleanup_free_ char *p = NULL, *b = NULL, *q = NULL, *d = NULL; char *id; int r; - if (arg_link_journal == LINK_NO) - return 0; - p = strappend(directory, "/etc/machine-id"); if (!p) return log_oom(); @@ -819,6 +855,24 @@ static int setup_journal(const char *directory) { return r; } + r = sd_id128_get_machine(&this_id); + if (r < 0) { + log_error("Failed to retrieve machine ID: %s", strerror(-r)); + return r; + } + + if (sd_id128_equal(machine_id, this_id)) { + log_full(arg_link_journal == LINK_AUTO ? LOG_WARNING : LOG_ERR, + "Host and machine ids are equal (%s): refusing to link journals", id); + if (arg_link_journal == LINK_AUTO) + return 0; + return + -EEXIST; + } + + if (arg_link_journal == LINK_NO) + return 0; + free(p); p = strappend("/var/log/journal/", id); q = strjoin(directory, "/var/log/journal/", id, NULL); @@ -919,11 +973,31 @@ static int setup_journal(const char *directory) { return 0; } +static int setup_kdbus(const char *dest, const char *path) { + const char *p; + + if (!path) + return 0; + + p = strappenda(dest, "/dev/kdbus"); + if (mkdir(p, 0755) < 0) { + log_error("Failed to create kdbus path: %m"); + return -errno; + } + + if (mount(path, p, "bind", MS_BIND, NULL) < 0) { + log_error("Failed to mount kdbus namespace path: %m"); + return -errno; + } + + return 0; +} + static int drop_capabilities(void) { return capability_bounding_set_drop(~arg_retain, false); } -static int register_machine(void) { +static int register_machine(pid_t pid) { _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL; _cleanup_bus_unref_ sd_bus *bus = NULL; int r; @@ -947,7 +1021,7 @@ static int register_machine(void) { SD_BUS_MESSAGE_APPEND_ID128(arg_uuid), "nspawn", "container", - (uint32_t) 0, + (uint32_t) pid, strempty(arg_directory), !isempty(arg_slice), "Slice", "s", arg_slice); if (r < 0) { @@ -965,7 +1039,7 @@ static int terminate_machine(pid_t pid) { const char *path; int r; - r = sd_bus_open_system(&bus); + r = sd_bus_default_system(&bus); if (r < 0) { log_error("Failed to open system bus: %s", strerror(-r)); return r; @@ -990,10 +1064,8 @@ static int terminate_machine(pid_t pid) { } r = sd_bus_message_read(reply, "o", &path); - if (r < 0) { - log_error("Failed to parse GetMachineByPID() reply: %s", bus_error_message(&error, r)); - return r; - } + if (r < 0) + return bus_log_parse_error(r); r = sd_bus_call_method( bus, @@ -1026,12 +1098,14 @@ static bool audit_enabled(void) { int main(int argc, char *argv[]) { pid_t pid = 0; int r = EXIT_FAILURE, k; - _cleanup_close_ int master = -1; + _cleanup_close_ int master = -1, kdbus_fd = -1, sync_fd = -1; int n_fd_passed; const char *console = NULL; sigset_t mask; _cleanup_close_pipe_ int kmsg_socket_pair[2] = { -1, -1 }; _cleanup_fdset_free_ FDSet *fds = NULL; + _cleanup_free_ char *kdbus_namespace = NULL; + const char *ns; log_parse_environment(); log_open(); @@ -1061,7 +1135,7 @@ int main(int argc, char *argv[]) { path_kill_slashes(arg_directory); if (!arg_machine) { - arg_machine = strdup(path_get_file_name(arg_directory)); + arg_machine = strdup(basename(arg_directory)); if (!arg_machine) { log_oom(); goto finish; @@ -1132,8 +1206,21 @@ int main(int argc, char *argv[]) { goto finish; } + ns = strappenda("machine-", arg_machine); + kdbus_fd = bus_kernel_create_namespace(ns, &kdbus_namespace); + if (r < 0) + log_debug("Failed to create kdbus namespace: %s", strerror(-r)); + else + log_debug("Successfully created kdbus namespace as %s", kdbus_namespace); + if (socketpair(AF_UNIX, SOCK_DGRAM|SOCK_NONBLOCK|SOCK_CLOEXEC, 0, kmsg_socket_pair) < 0) { - log_error("Failed to create kmsg socket pair."); + log_error("Failed to create kmsg socket pair: %m"); + goto finish; + } + + sync_fd = eventfd(0, EFD_CLOEXEC); + if (sync_fd < 0) { + log_error("Failed to create event fd: %m"); goto finish; } @@ -1163,7 +1250,7 @@ int main(int argc, char *argv[]) { gid_t gid = (gid_t) -1; unsigned n_env = 2; const char *envp[] = { - "PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin", + "PATH=" DEFAULT_PATH_SPLIT_USR, "container=systemd-nspawn", /* LXC sets container=lxc, so follow the scheme here */ NULL, /* TERM */ NULL, /* HOME */ @@ -1174,6 +1261,8 @@ int main(int argc, char *argv[]) { NULL, /* LISTEN_PID */ NULL }; + char **env_use; + eventfd_t x; envp[n_env] = strv_find_prefix(environ, "TERM="); if (envp[n_env]) @@ -1221,10 +1310,6 @@ int main(int argc, char *argv[]) { goto child_fail; } - r = register_machine(); - if (r < 0) - goto finish; - /* Mark everything as slave, so that we still * receive mounts from the real root, but don't * propagate mounts to the real root. */ @@ -1283,6 +1368,9 @@ int main(int argc, char *argv[]) { if (mount_binds(arg_directory, arg_bind_ro, MS_RDONLY) < 0) goto child_fail; + if (setup_kdbus(arg_directory, kdbus_namespace) < 0) + goto child_fail; + if (chdir(arg_directory) < 0) { log_error("chdir(%s) failed: %m", arg_directory); goto child_fail; @@ -1398,6 +1486,23 @@ int main(int argc, char *argv[]) { setup_hostname(); + eventfd_read(sync_fd, &x); + close_nointr_nofail(sync_fd); + sync_fd = -1; + + if (!strv_isempty(arg_setenv)) { + char **n; + + n = strv_env_merge(2, envp, arg_setenv); + if (!n) { + log_oom(); + goto child_fail; + } + + env_use = n; + } else + env_use = (char**) envp; + if (arg_boot) { char **a; size_t l; @@ -1409,18 +1514,18 @@ int main(int argc, char *argv[]) { memcpy(a + 1, argv + optind, l * sizeof(char*)); a[0] = (char*) "/usr/lib/systemd/systemd"; - execve(a[0], a, (char**) envp); + execve(a[0], a, env_use); a[0] = (char*) "/lib/systemd/systemd"; - execve(a[0], a, (char**) envp); + execve(a[0], a, env_use); a[0] = (char*) "/sbin/init"; - execve(a[0], a, (char**) envp); + execve(a[0], a, env_use); } else if (argc > optind) - execvpe(argv[optind], argv + optind, (char**) envp); + execvpe(argv[optind], argv + optind, env_use); else { chdir(home ? home : "/root"); - execle("/bin/bash", "-bash", NULL, (char**) envp); + execle("/bin/bash", "-bash", NULL, env_use); } log_error("execv() failed: %m"); @@ -1432,6 +1537,14 @@ int main(int argc, char *argv[]) { fdset_free(fds); fds = NULL; + r = register_machine(pid); + if (r < 0) + goto finish; + + eventfd_write(sync_fd, 1); + close_nointr_nofail(sync_fd); + sync_fd = -1; + k = process_pty(master, &mask, arg_boot ? pid : 0, SIGRTMIN+3); if (k < 0) { r = EXIT_FAILURE; @@ -1491,6 +1604,7 @@ finish: free(arg_directory); free(arg_machine); + free(arg_setenv); return r; }