X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Fnspawn%2Fnspawn.c;h=0b25334fe9eab93444502fcc07c4d35f5e15c5c8;hp=be8161c351917c5cb3a38defea971e4d13fd4858;hb=39ed67d14694983dabd6641c02216aa440eed767;hpb=fcf90586a2b26c445d6a35313990096c8562ecee diff --git a/src/nspawn/nspawn.c b/src/nspawn/nspawn.c index be8161c35..0b25334fe 100644 --- a/src/nspawn/nspawn.c +++ b/src/nspawn/nspawn.c @@ -80,8 +80,8 @@ static char *arg_directory = NULL; static char *arg_user = NULL; static sd_id128_t arg_uuid = {}; static char *arg_machine = NULL; -static char *arg_process_label = NULL; -static char *arg_apifs_label = NULL; +static char *arg_selinux_context = NULL; +static char *arg_selinux_apifs_context = NULL; static const char *arg_slice = NULL; static bool arg_private_network = false; static bool arg_read_only = false; @@ -118,6 +118,9 @@ static char **arg_bind = NULL; static char **arg_bind_ro = NULL; static char **arg_setenv = NULL; static bool arg_quiet = false; +static bool arg_share_system = false; +static bool arg_register = true; +static bool arg_keep_unit = false; static int help(void) { @@ -131,11 +134,14 @@ static int help(void) { " --uuid=UUID Set a specific machine UUID for the container\n" " -M --machine=NAME Set the machine name for the container\n" " -S --slice=SLICE Place the container in the specified slice\n" - " -L --apifs-label=LABEL Set the MAC file label to be used by API/tmpfs file\n" - " systems in the container\n" - " -Z --process-label=LABEL Set the MAC label to be used by processes in\n" - " the container\n" + " -Z --selinux-context=SECLABEL\n" + " Set the SELinux security context to be used by\n" + " processes in the container\n" + " -L --selinux-apifs-context=SECLABEL\n" + " Set the SELinux security context to be used by\n" + " API/tmpfs file systems in the container\n" " --private-network Disable network in container\n" + " --share-system Share system namespaces with host\n" " --read-only Mount the root directory read-only\n" " --capability=CAP In addition to the default, retain specified\n" " capability\n" @@ -146,6 +152,9 @@ static int help(void) { " the container\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" + " --register=BOOLEAN Register container as machine\n" + " --keep-unit Do not register a scope for the machine, reuse\n" + " the service unit nspawn is running in\n" " -q --quiet Do not show status information\n", program_invocation_short_name); @@ -165,28 +174,34 @@ static int parse_argv(int argc, char *argv[]) { ARG_BIND, ARG_BIND_RO, ARG_SETENV, + ARG_SHARE_SYSTEM, + ARG_REGISTER, + ARG_KEEP_UNIT }; 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' }, - { "private-network", no_argument, NULL, ARG_PRIVATE_NETWORK }, - { "boot", no_argument, NULL, 'b' }, - { "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 }, - { "process-label", required_argument, NULL, 'Z' }, - { "apifs-label", required_argument, NULL, 'L' }, - { "quiet", no_argument, NULL, 'q' }, + { "help", no_argument, NULL, 'h' }, + { "version", no_argument, NULL, ARG_VERSION }, + { "directory", required_argument, NULL, 'D' }, + { "user", required_argument, NULL, 'u' }, + { "private-network", no_argument, NULL, ARG_PRIVATE_NETWORK }, + { "boot", no_argument, NULL, 'b' }, + { "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 }, + { "selinux-context", required_argument, NULL, 'Z' }, + { "selinux-apifs-context", required_argument, NULL, 'L' }, + { "quiet", no_argument, NULL, 'q' }, + { "share-system", no_argument, NULL, ARG_SHARE_SYSTEM }, + { "register", required_argument, NULL, ARG_REGISTER }, + { "keep-unit", no_argument, NULL, ARG_KEEP_UNIT }, {} }; @@ -249,24 +264,30 @@ static int parse_argv(int argc, char *argv[]) { break; case 'M': - if (!hostname_is_valid(optarg)) { - log_error("Invalid machine name: %s", optarg); - return -EINVAL; - } + if (isempty(optarg)) { + free(arg_machine); + arg_machine = NULL; + } else { - free(arg_machine); - arg_machine = strdup(optarg); - if (!arg_machine) - return log_oom(); + if (!hostname_is_valid(optarg)) { + log_error("Invalid machine name: %s", optarg); + return -EINVAL; + } - break; + free(arg_machine); + arg_machine = strdup(optarg); + if (!arg_machine) + return log_oom(); - case 'L': - arg_apifs_label = optarg; - break; + break; + } case 'Z': - arg_process_label = optarg; + arg_selinux_context = optarg; + break; + + case 'L': + arg_selinux_apifs_context = optarg; break; case ARG_READ_ONLY: @@ -279,25 +300,29 @@ static int parse_argv(int argc, char *argv[]) { size_t length; FOREACH_WORD_SEPARATOR(word, length, optarg, ",", state) { + _cleanup_free_ char *t; cap_value_t cap; - char *t; t = strndup(word, length); if (!t) return log_oom(); - if (cap_from_name(t, &cap) < 0) { - log_error("Failed to parse capability %s.", t); - free(t); - return -EINVAL; + if (streq(t, "all")) { + if (c == ARG_CAPABILITY) + arg_retain = (uint64_t) -1; + else + arg_retain = 0; + } else { + if (cap_from_name(t, &cap) < 0) { + log_error("Failed to parse capability %s.", t); + return -EINVAL; + } + + if (c == ARG_CAPABILITY) + arg_retain |= 1ULL << (uint64_t) cap; + else + arg_retain &= ~(1ULL << (uint64_t) cap); } - - free(t); - - if (c == ARG_CAPABILITY) - arg_retain |= 1ULL << (uint64_t) cap; - else - arg_retain &= ~(1ULL << (uint64_t) cap); } break; @@ -380,6 +405,24 @@ static int parse_argv(int argc, char *argv[]) { arg_quiet = true; break; + case ARG_SHARE_SYSTEM: + arg_share_system = true; + break; + + case ARG_REGISTER: + r = parse_boolean(optarg); + if (r < 0) { + log_error("Failed to parse --register= argument: %s", optarg); + return r; + } + + arg_register = r; + break; + + case ARG_KEEP_UNIT: + arg_keep_unit = true; + break; + case '?': return -EINVAL; @@ -388,6 +431,19 @@ static int parse_argv(int argc, char *argv[]) { } } + if (arg_share_system) + arg_register = false; + + if (arg_boot && arg_share_system) { + log_error("--boot and --share-system may not be combined."); + return -EINVAL; + } + + if (arg_keep_unit && cg_pid_get_owner_uid(0, NULL) >= 0) { + log_error("--keep-unit may not be used when invoked from a user session."); + return -EINVAL; + } + return 1; } @@ -449,8 +505,9 @@ static int mount_all(const char *dest) { mkdir_p(where, 0755); #ifdef HAVE_SELINUX - if (arg_apifs_label && (streq_ptr(mount_table[k].what, "tmpfs") || streq_ptr(mount_table[k].what, "devpts"))) { - options = strjoin(mount_table[k].options, ",context=\"", arg_apifs_label, "\"", NULL); + if (arg_selinux_apifs_context && + (streq_ptr(mount_table[k].what, "tmpfs") || streq_ptr(mount_table[k].what, "devpts"))) { + options = strjoin(mount_table[k].options, ",context=\"", arg_selinux_apifs_context, "\"", NULL); if (!options) return log_oom(); @@ -625,6 +682,9 @@ static int setup_boot_id(const char *dest) { assert(dest); + if (arg_share_system) + return 0; + /* Generate a new randomized boot ID, so that each boot-up of * the container gets a new one */ @@ -850,6 +910,9 @@ static int setup_kmsg(const char *dest, int kmsg_socket) { static int setup_hostname(void) { + if (arg_share_system) + return 0; + if (sethostname(arg_machine, strlen(arg_machine)) < 0) return -errno; @@ -1032,28 +1095,50 @@ static int register_machine(pid_t pid) { _cleanup_bus_unref_ sd_bus *bus = NULL; int r; + if (!arg_register) + return 0; + r = sd_bus_default_system(&bus); if (r < 0) { log_error("Failed to open system bus: %s", strerror(-r)); return r; } - r = sd_bus_call_method( - bus, - "org.freedesktop.machine1", - "/org/freedesktop/machine1", - "org.freedesktop.machine1.Manager", - "CreateMachine", - &error, - NULL, - "sayssusa(sv)", - arg_machine, - SD_BUS_MESSAGE_APPEND_ID128(arg_uuid), - "nspawn", - "container", - (uint32_t) pid, - strempty(arg_directory), - !isempty(arg_slice), "Slice", "s", arg_slice); + if (arg_keep_unit) { + r = sd_bus_call_method( + bus, + "org.freedesktop.machine1", + "/org/freedesktop/machine1", + "org.freedesktop.machine1.Manager", + "RegisterMachine", + &error, + NULL, + "sayssus", + arg_machine, + SD_BUS_MESSAGE_APPEND_ID128(arg_uuid), + "nspawn", + "container", + (uint32_t) pid, + strempty(arg_directory)); + } else { + r = sd_bus_call_method( + bus, + "org.freedesktop.machine1", + "/org/freedesktop/machine1", + "org.freedesktop.machine1.Manager", + "CreateMachine", + &error, + NULL, + "sayssusa(sv)", + arg_machine, + SD_BUS_MESSAGE_APPEND_ID128(arg_uuid), + "nspawn", + "container", + (uint32_t) pid, + strempty(arg_directory), + !isempty(arg_slice), "Slice", "s", arg_slice); + } + if (r < 0) { log_error("Failed to register machine: %s", bus_error_message(&error, r)); return r; @@ -1069,6 +1154,9 @@ static int terminate_machine(pid_t pid) { const char *path; int r; + if (!arg_register) + return 0; + r = sd_bus_default_system(&bus); if (r < 0) { log_error("Failed to open system bus: %s", strerror(-r)); @@ -1114,15 +1202,37 @@ static int terminate_machine(pid_t pid) { return 0; } -static bool audit_enabled(void) { - int fd; +static int reset_audit_loginuid(void) { + _cleanup_free_ char *p = NULL; + int r; - fd = socket(AF_NETLINK, SOCK_RAW, NETLINK_AUDIT); - if (fd >= 0) { - close_nointr_nofail(fd); - return true; + if (arg_share_system) + return 0; + + r = read_one_line_file("/proc/self/loginuid", &p); + if (r == -EEXIST) + return 0; + if (r < 0) { + log_error("Failed to read /proc/self/loginuid: %s", strerror(-r)); + return r; } - return false; + + /* Already reset? */ + if (streq(p, "4294967295")) + return 0; + + r = write_string_file("/proc/self/loginuid", "4294967295"); + if (r < 0) { + log_error("Failed to reset audit login UID. This probably means that your kernel is too\n" + "old and you have audit enabled. Note that the auditing subsystem is known to\n" + "be incompatible with containers on old kernels. Please make sure to upgrade\n" + "your kernel or to off auditing with 'audit=0' on the kernel command line before\n" + "using systemd-nspawn. Sleeping for 5s... (%s)\n", strerror(-r)); + + sleep(5); + } + + return 0; } int main(int argc, char *argv[]) { @@ -1135,7 +1245,6 @@ int main(int argc, char *argv[]) { _cleanup_close_pipe_ int kmsg_socket_pair[2] = { -1, -1 }; _cleanup_fdset_free_ FDSet *fds = NULL; _cleanup_free_ char *kdbus_domain = NULL; - const char *ns; log_parse_environment(); log_open(); @@ -1188,13 +1297,6 @@ int main(int argc, char *argv[]) { goto finish; } - if (arg_boot && audit_enabled()) { - log_warning("The kernel auditing subsystem is known to be incompatible with containers.\n" - "Please make sure to turn off auditing with 'audit=0' on the kernel command\n" - "line before using systemd-nspawn. Sleeping for 5s...\n"); - sleep(5); - } - if (path_equal(arg_directory, "/")) { log_error("Spawning container on root directory not supported."); goto finish; @@ -1237,12 +1339,26 @@ int main(int argc, char *argv[]) { goto finish; } - ns = strappenda("machine-", arg_machine); - kdbus_fd = bus_kernel_create_domain(ns, &kdbus_domain); - if (r < 0) - log_debug("Failed to create kdbus domain: %s", strerror(-r)); - else - log_debug("Successfully created kdbus domain as %s", kdbus_domain); + + if (access("/dev/kdbus/control", F_OK) >= 0) { + + if (arg_share_system) { + kdbus_domain = strdup("/dev/kdbus"); + if (!kdbus_domain) { + log_oom(); + goto finish; + } + } else { + const char *ns; + + ns = strappenda("machine-", arg_machine); + kdbus_fd = bus_kernel_create_domain(ns, &kdbus_domain); + if (r < 0) + log_debug("Failed to create kdbus domain: %s", strerror(-r)); + else + log_debug("Successfully created kdbus domain as %s", kdbus_domain); + } + } if (socketpair(AF_UNIX, SOCK_DGRAM|SOCK_NONBLOCK|SOCK_CLOEXEC, 0, kmsg_socket_pair) < 0) { log_error("Failed to create kmsg socket pair: %m"); @@ -1264,7 +1380,10 @@ int main(int argc, char *argv[]) { goto finish; } - pid = syscall(__NR_clone, SIGCHLD|CLONE_NEWIPC|CLONE_NEWNS|CLONE_NEWPID|CLONE_NEWUTS|(arg_private_network ? CLONE_NEWNET : 0), NULL); + pid = syscall(__NR_clone, + SIGCHLD|CLONE_NEWNS| + (arg_share_system ? 0 : CLONE_NEWIPC|CLONE_NEWPID|CLONE_NEWUTS)| + (arg_private_network ? CLONE_NEWNET : 0), NULL); if (pid < 0) { if (errno == EINVAL) log_error("clone() failed, do you have namespace support enabled in your kernel? (You need UTS, IPC, PID and NET namespacing built in): %m"); @@ -1336,6 +1455,9 @@ int main(int argc, char *argv[]) { goto child_fail; } + if (reset_audit_loginuid() < 0) + goto child_fail; + if (prctl(PR_SET_PDEATHSIG, SIGKILL) < 0) { log_error("PR_SET_PDEATHSIG failed: %m"); goto child_fail; @@ -1424,7 +1546,8 @@ int main(int argc, char *argv[]) { umask(0022); - loopback_setup(); + if (arg_private_network) + loopback_setup(); if (drop_capabilities() < 0) { log_error("drop_capabilities() failed: %m"); @@ -1535,9 +1658,9 @@ int main(int argc, char *argv[]) { env_use = (char**) envp; #ifdef HAVE_SELINUX - if (arg_process_label) - if (setexeccon(arg_process_label) < 0) - log_error("setexeccon(\"%s\") failed: %m", arg_process_label); + if (arg_selinux_context) + if (setexeccon(arg_selinux_context) < 0) + log_error("setexeccon(\"%s\") failed: %m", arg_selinux_context); #endif if (arg_boot) { char **a; @@ -1630,7 +1753,7 @@ int main(int argc, char *argv[]) { } else if (status.si_code == CLD_KILLED || status.si_code == CLD_DUMPED) { - log_error("Container %s terminated by signal %s.", arg_machine, signal_to_string(status.si_status)); + log_error("Container %s terminated by signal %s.", arg_machine, signal_to_string(status.si_status)); r = EXIT_FAILURE; break; } else {