diff options
Diffstat (limited to '')
| -rw-r--r-- | src/core/socket.c | 3339 |
1 files changed, 3339 insertions, 0 deletions
diff --git a/src/core/socket.c b/src/core/socket.c new file mode 100644 index 0000000..af95e90 --- /dev/null +++ b/src/core/socket.c @@ -0,0 +1,3339 @@ +/* SPDX-License-Identifier: LGPL-2.1+ */ + +#include <arpa/inet.h> +#include <errno.h> +#include <fcntl.h> +#include <mqueue.h> +#include <netinet/tcp.h> +#include <signal.h> +#include <sys/epoll.h> +#include <sys/stat.h> +#include <unistd.h> +#include <linux/sctp.h> + +#include "alloc-util.h" +#include "bpf-firewall.h" +#include "bus-error.h" +#include "bus-util.h" +#include "copy.h" +#include "dbus-socket.h" +#include "dbus-unit.h" +#include "def.h" +#include "exit-status.h" +#include "fd-util.h" +#include "format-util.h" +#include "fs-util.h" +#include "in-addr-util.h" +#include "io-util.h" +#include "ip-protocol-list.h" +#include "label.h" +#include "log.h" +#include "missing.h" +#include "mkdir.h" +#include "parse-util.h" +#include "path-util.h" +#include "process-util.h" +#include "selinux-util.h" +#include "serialize.h" +#include "signal-util.h" +#include "smack-util.h" +#include "socket.h" +#include "special.h" +#include "string-table.h" +#include "string-util.h" +#include "strv.h" +#include "unit-name.h" +#include "unit.h" +#include "user-util.h" + +struct SocketPeer { + unsigned n_ref; + + Socket *socket; + union sockaddr_union peer; + socklen_t peer_salen; +}; + +static const UnitActiveState state_translation_table[_SOCKET_STATE_MAX] = { + [SOCKET_DEAD] = UNIT_INACTIVE, + [SOCKET_START_PRE] = UNIT_ACTIVATING, + [SOCKET_START_CHOWN] = UNIT_ACTIVATING, + [SOCKET_START_POST] = UNIT_ACTIVATING, + [SOCKET_LISTENING] = UNIT_ACTIVE, + [SOCKET_RUNNING] = UNIT_ACTIVE, + [SOCKET_STOP_PRE] = UNIT_DEACTIVATING, + [SOCKET_STOP_PRE_SIGTERM] = UNIT_DEACTIVATING, + [SOCKET_STOP_PRE_SIGKILL] = UNIT_DEACTIVATING, + [SOCKET_STOP_POST] = UNIT_DEACTIVATING, + [SOCKET_FINAL_SIGTERM] = UNIT_DEACTIVATING, + [SOCKET_FINAL_SIGKILL] = UNIT_DEACTIVATING, + [SOCKET_FAILED] = UNIT_FAILED +}; + +static int socket_dispatch_io(sd_event_source *source, int fd, uint32_t revents, void *userdata); +static int socket_dispatch_timer(sd_event_source *source, usec_t usec, void *userdata); + +static void socket_init(Unit *u) { + Socket *s = SOCKET(u); + + assert(u); + assert(u->load_state == UNIT_STUB); + + s->backlog = SOMAXCONN; + s->timeout_usec = u->manager->default_timeout_start_usec; + s->directory_mode = 0755; + s->socket_mode = 0666; + + s->max_connections = 64; + + s->priority = -1; + s->ip_tos = -1; + s->ip_ttl = -1; + s->mark = -1; + + s->exec_context.std_output = u->manager->default_std_output; + s->exec_context.std_error = u->manager->default_std_error; + + s->control_command_id = _SOCKET_EXEC_COMMAND_INVALID; + + s->trigger_limit.interval = USEC_INFINITY; + s->trigger_limit.burst = (unsigned) -1; +} + +static void socket_unwatch_control_pid(Socket *s) { + assert(s); + + if (s->control_pid <= 0) + return; + + unit_unwatch_pid(UNIT(s), s->control_pid); + s->control_pid = 0; +} + +static void socket_cleanup_fd_list(SocketPort *p) { + assert(p); + + close_many(p->auxiliary_fds, p->n_auxiliary_fds); + p->auxiliary_fds = mfree(p->auxiliary_fds); + p->n_auxiliary_fds = 0; +} + +void socket_free_ports(Socket *s) { + SocketPort *p; + + assert(s); + + while ((p = s->ports)) { + LIST_REMOVE(port, s->ports, p); + + sd_event_source_unref(p->event_source); + + socket_cleanup_fd_list(p); + safe_close(p->fd); + free(p->path); + free(p); + } +} + +static void socket_done(Unit *u) { + Socket *s = SOCKET(u); + SocketPeer *p; + + assert(s); + + socket_free_ports(s); + + while ((p = set_steal_first(s->peers_by_address))) + p->socket = NULL; + + s->peers_by_address = set_free(s->peers_by_address); + + s->exec_runtime = exec_runtime_unref(s->exec_runtime, false); + exec_command_free_array(s->exec_command, _SOCKET_EXEC_COMMAND_MAX); + s->control_command = NULL; + + dynamic_creds_unref(&s->dynamic_creds); + + socket_unwatch_control_pid(s); + + unit_ref_unset(&s->service); + + s->tcp_congestion = mfree(s->tcp_congestion); + s->bind_to_device = mfree(s->bind_to_device); + + s->smack = mfree(s->smack); + s->smack_ip_in = mfree(s->smack_ip_in); + s->smack_ip_out = mfree(s->smack_ip_out); + + strv_free(s->symlinks); + + s->user = mfree(s->user); + s->group = mfree(s->group); + + s->fdname = mfree(s->fdname); + + s->timer_event_source = sd_event_source_unref(s->timer_event_source); +} + +static int socket_arm_timer(Socket *s, usec_t usec) { + int r; + + assert(s); + + if (s->timer_event_source) { + r = sd_event_source_set_time(s->timer_event_source, usec); + if (r < 0) + return r; + + return sd_event_source_set_enabled(s->timer_event_source, SD_EVENT_ONESHOT); + } + + if (usec == USEC_INFINITY) + return 0; + + r = sd_event_add_time( + UNIT(s)->manager->event, + &s->timer_event_source, + CLOCK_MONOTONIC, + usec, 0, + socket_dispatch_timer, s); + if (r < 0) + return r; + + (void) sd_event_source_set_description(s->timer_event_source, "socket-timer"); + + return 0; +} + +int socket_instantiate_service(Socket *s) { + _cleanup_free_ char *prefix = NULL, *name = NULL; + int r; + Unit *u; + + assert(s); + + /* This fills in s->service if it isn't filled in yet. For + * Accept=yes sockets we create the next connection service + * here. For Accept=no this is mostly a NOP since the service + * is figured out at load time anyway. */ + + if (UNIT_DEREF(s->service)) + return 0; + + if (!s->accept) + return 0; + + r = unit_name_to_prefix(UNIT(s)->id, &prefix); + if (r < 0) + return r; + + if (asprintf(&name, "%s@%u.service", prefix, s->n_accepted) < 0) + return -ENOMEM; + + r = manager_load_unit(UNIT(s)->manager, name, NULL, NULL, &u); + if (r < 0) + return r; + + unit_ref_set(&s->service, UNIT(s), u); + + return unit_add_two_dependencies(UNIT(s), UNIT_BEFORE, UNIT_TRIGGERS, u, false, UNIT_DEPENDENCY_IMPLICIT); +} + +static bool have_non_accept_socket(Socket *s) { + SocketPort *p; + + assert(s); + + if (!s->accept) + return true; + + LIST_FOREACH(port, p, s->ports) { + + if (p->type != SOCKET_SOCKET) + return true; + + if (!socket_address_can_accept(&p->address)) + return true; + } + + return false; +} + +static int socket_add_mount_dependencies(Socket *s) { + SocketPort *p; + int r; + + assert(s); + + LIST_FOREACH(port, p, s->ports) { + const char *path = NULL; + + if (p->type == SOCKET_SOCKET) + path = socket_address_get_path(&p->address); + else if (IN_SET(p->type, SOCKET_FIFO, SOCKET_SPECIAL, SOCKET_USB_FUNCTION)) + path = p->path; + + if (!path) + continue; + + r = unit_require_mounts_for(UNIT(s), path, UNIT_DEPENDENCY_FILE); + if (r < 0) + return r; + } + + return 0; +} + +static int socket_add_device_dependencies(Socket *s) { + char *t; + + assert(s); + + if (!s->bind_to_device || streq(s->bind_to_device, "lo")) + return 0; + + t = strjoina("/sys/subsystem/net/devices/", s->bind_to_device); + return unit_add_node_dependency(UNIT(s), t, false, UNIT_BINDS_TO, UNIT_DEPENDENCY_FILE); +} + +static int socket_add_default_dependencies(Socket *s) { + int r; + assert(s); + + if (!UNIT(s)->default_dependencies) + return 0; + + r = unit_add_dependency_by_name(UNIT(s), UNIT_BEFORE, SPECIAL_SOCKETS_TARGET, true, UNIT_DEPENDENCY_DEFAULT); + if (r < 0) + return r; + + if (MANAGER_IS_SYSTEM(UNIT(s)->manager)) { + r = unit_add_two_dependencies_by_name(UNIT(s), UNIT_AFTER, UNIT_REQUIRES, SPECIAL_SYSINIT_TARGET, true, UNIT_DEPENDENCY_DEFAULT); + if (r < 0) + return r; + } + + return unit_add_two_dependencies_by_name(UNIT(s), UNIT_BEFORE, UNIT_CONFLICTS, SPECIAL_SHUTDOWN_TARGET, true, UNIT_DEPENDENCY_DEFAULT); +} + +_pure_ static bool socket_has_exec(Socket *s) { + unsigned i; + assert(s); + + for (i = 0; i < _SOCKET_EXEC_COMMAND_MAX; i++) + if (s->exec_command[i]) + return true; + + return false; +} + +static int socket_add_extras(Socket *s) { + Unit *u = UNIT(s); + int r; + + assert(s); + + /* Pick defaults for the trigger limit, if nothing was explicitly configured. We pick a relatively high limit + * in Accept=yes mode, and a lower limit for Accept=no. Reason: in Accept=yes mode we are invoking accept() + * ourselves before the trigger limit can hit, thus incoming connections are taken off the socket queue quickly + * and reliably. This is different for Accept=no, where the spawned service has to take the incoming traffic + * off the queues, which it might not necessarily do. Moreover, while Accept=no services are supposed to + * process whatever is queued in one go, and thus should normally never have to be started frequently. This is + * different for Accept=yes where each connection is processed by a new service instance, and thus frequent + * service starts are typical. */ + + if (s->trigger_limit.interval == USEC_INFINITY) + s->trigger_limit.interval = 2 * USEC_PER_SEC; + + if (s->trigger_limit.burst == (unsigned) -1) { + if (s->accept) + s->trigger_limit.burst = 200; + else + s->trigger_limit.burst = 20; + } + + if (have_non_accept_socket(s)) { + + if (!UNIT_DEREF(s->service)) { + Unit *x; + + r = unit_load_related_unit(u, ".service", &x); + if (r < 0) + return r; + + unit_ref_set(&s->service, u, x); + } + + r = unit_add_two_dependencies(u, UNIT_BEFORE, UNIT_TRIGGERS, UNIT_DEREF(s->service), true, UNIT_DEPENDENCY_IMPLICIT); + if (r < 0) + return r; + } + + r = socket_add_mount_dependencies(s); + if (r < 0) + return r; + + r = socket_add_device_dependencies(s); + if (r < 0) + return r; + + r = unit_patch_contexts(u); + if (r < 0) + return r; + + if (socket_has_exec(s)) { + r = unit_add_exec_dependencies(u, &s->exec_context); + if (r < 0) + return r; + } + + r = unit_set_default_slice(u); + if (r < 0) + return r; + + r = socket_add_default_dependencies(s); + if (r < 0) + return r; + + return 0; +} + +static const char *socket_find_symlink_target(Socket *s) { + const char *found = NULL; + SocketPort *p; + + LIST_FOREACH(port, p, s->ports) { + const char *f = NULL; + + switch (p->type) { + + case SOCKET_FIFO: + f = p->path; + break; + + case SOCKET_SOCKET: + f = socket_address_get_path(&p->address); + break; + + default: + break; + } + + if (f) { + if (found) + return NULL; + + found = f; + } + } + + return found; +} + +static int socket_verify(Socket *s) { + assert(s); + + if (UNIT(s)->load_state != UNIT_LOADED) + return 0; + + if (!s->ports) { + log_unit_error(UNIT(s), "Unit has no Listen setting (ListenStream=, ListenDatagram=, ListenFIFO=, ...). Refusing."); + return -ENOEXEC; + } + + if (s->accept && have_non_accept_socket(s)) { + log_unit_error(UNIT(s), "Unit configured for accepting sockets, but sockets are non-accepting. Refusing."); + return -ENOEXEC; + } + + if (s->accept && s->max_connections <= 0) { + log_unit_error(UNIT(s), "MaxConnection= setting too small. Refusing."); + return -ENOEXEC; + } + + if (s->accept && UNIT_DEREF(s->service)) { + log_unit_error(UNIT(s), "Explicit service configuration for accepting socket units not supported. Refusing."); + return -ENOEXEC; + } + + if (s->exec_context.pam_name && s->kill_context.kill_mode != KILL_CONTROL_GROUP) { + log_unit_error(UNIT(s), "Unit has PAM enabled. Kill mode must be set to 'control-group'. Refusing."); + return -ENOEXEC; + } + + if (!strv_isempty(s->symlinks) && !socket_find_symlink_target(s)) { + log_unit_error(UNIT(s), "Unit has symlinks set but none or more than one node in the file system. Refusing."); + return -ENOEXEC; + } + + return 0; +} + +static void peer_address_hash_func(const SocketPeer *s, struct siphash *state) { + assert(s); + + if (s->peer.sa.sa_family == AF_INET) + siphash24_compress(&s->peer.in.sin_addr, sizeof(s->peer.in.sin_addr), state); + else if (s->peer.sa.sa_family == AF_INET6) + siphash24_compress(&s->peer.in6.sin6_addr, sizeof(s->peer.in6.sin6_addr), state); + else if (s->peer.sa.sa_family == AF_VSOCK) + siphash24_compress(&s->peer.vm.svm_cid, sizeof(s->peer.vm.svm_cid), state); + else + assert_not_reached("Unknown address family."); +} + +static int peer_address_compare_func(const SocketPeer *x, const SocketPeer *y) { + int r; + + r = CMP(x->peer.sa.sa_family, y->peer.sa.sa_family); + if (r != 0) + return r; + + switch(x->peer.sa.sa_family) { + case AF_INET: + return memcmp(&x->peer.in.sin_addr, &y->peer.in.sin_addr, sizeof(x->peer.in.sin_addr)); + case AF_INET6: + return memcmp(&x->peer.in6.sin6_addr, &y->peer.in6.sin6_addr, sizeof(x->peer.in6.sin6_addr)); + case AF_VSOCK: + return CMP(x->peer.vm.svm_cid, y->peer.vm.svm_cid); + } + assert_not_reached("Black sheep in the family!"); +} + +DEFINE_PRIVATE_HASH_OPS(peer_address_hash_ops, SocketPeer, peer_address_hash_func, peer_address_compare_func); + +static int socket_load(Unit *u) { + Socket *s = SOCKET(u); + int r; + + assert(u); + assert(u->load_state == UNIT_STUB); + + r = set_ensure_allocated(&s->peers_by_address, &peer_address_hash_ops); + if (r < 0) + return r; + + r = unit_load_fragment_and_dropin(u); + if (r < 0) + return r; + + if (u->load_state == UNIT_LOADED) { + /* This is a new unit? Then let's add in some extras */ + r = socket_add_extras(s); + if (r < 0) + return r; + } + + return socket_verify(s); +} + +static SocketPeer *socket_peer_new(void) { + SocketPeer *p; + + p = new0(SocketPeer, 1); + if (!p) + return NULL; + + p->n_ref = 1; + + return p; +} + +static SocketPeer *socket_peer_free(SocketPeer *p) { + assert(p); + + if (p->socket) + set_remove(p->socket->peers_by_address, p); + + return mfree(p); +} + +DEFINE_TRIVIAL_REF_UNREF_FUNC(SocketPeer, socket_peer, socket_peer_free); + +int socket_acquire_peer(Socket *s, int fd, SocketPeer **p) { + _cleanup_(socket_peer_unrefp) SocketPeer *remote = NULL; + SocketPeer sa = {}, *i; + socklen_t salen = sizeof(sa.peer); + int r; + + assert(fd >= 0); + assert(s); + + r = getpeername(fd, &sa.peer.sa, &salen); + if (r < 0) + return log_unit_error_errno(UNIT(s), errno, "getpeername failed: %m"); + + if (!IN_SET(sa.peer.sa.sa_family, AF_INET, AF_INET6, AF_VSOCK)) { + *p = NULL; + return 0; + } + + i = set_get(s->peers_by_address, &sa); + if (i) { + *p = socket_peer_ref(i); + return 1; + } + + remote = socket_peer_new(); + if (!remote) + return log_oom(); + + remote->peer = sa.peer; + remote->peer_salen = salen; + + r = set_put(s->peers_by_address, remote); + if (r < 0) + return r; + + remote->socket = s; + + *p = TAKE_PTR(remote); + + return 1; +} + +_const_ static const char* listen_lookup(int family, int type) { + + if (family == AF_NETLINK) + return "ListenNetlink"; + + if (type == SOCK_STREAM) + return "ListenStream"; + else if (type == SOCK_DGRAM) + return "ListenDatagram"; + else if (type == SOCK_SEQPACKET) + return "ListenSequentialPacket"; + + assert_not_reached("Unknown socket type"); + return NULL; +} + +static void socket_dump(Unit *u, FILE *f, const char *prefix) { + char time_string[FORMAT_TIMESPAN_MAX]; + SocketExecCommand c; + Socket *s = SOCKET(u); + SocketPort *p; + const char *prefix2, *str; + + assert(s); + assert(f); + + prefix = strempty(prefix); + prefix2 = strjoina(prefix, "\t"); + + fprintf(f, + "%sSocket State: %s\n" + "%sResult: %s\n" + "%sBindIPv6Only: %s\n" + "%sBacklog: %u\n" + "%sSocketMode: %04o\n" + "%sDirectoryMode: %04o\n" + "%sKeepAlive: %s\n" + "%sNoDelay: %s\n" + "%sFreeBind: %s\n" + "%sTransparent: %s\n" + "%sBroadcast: %s\n" + "%sPassCredentials: %s\n" + "%sPassSecurity: %s\n" + "%sTCPCongestion: %s\n" + "%sRemoveOnStop: %s\n" + "%sWritable: %s\n" + "%sFileDescriptorName: %s\n" + "%sSELinuxContextFromNet: %s\n", + prefix, socket_state_to_string(s->state), + prefix, socket_result_to_string(s->result), + prefix, socket_address_bind_ipv6_only_to_string(s->bind_ipv6_only), + prefix, s->backlog, + prefix, s->socket_mode, + prefix, s->directory_mode, + prefix, yes_no(s->keep_alive), + prefix, yes_no(s->no_delay), + prefix, yes_no(s->free_bind), + prefix, yes_no(s->transparent), + prefix, yes_no(s->broadcast), + prefix, yes_no(s->pass_cred), + prefix, yes_no(s->pass_sec), + prefix, strna(s->tcp_congestion), + prefix, yes_no(s->remove_on_stop), + prefix, yes_no(s->writable), + prefix, socket_fdname(s), + prefix, yes_no(s->selinux_context_from_net)); + + if (s->control_pid > 0) + fprintf(f, + "%sControl PID: "PID_FMT"\n", + prefix, s->control_pid); + + if (s->bind_to_device) + fprintf(f, + "%sBindToDevice: %s\n", + prefix, s->bind_to_device); + + if (s->accept) + fprintf(f, + "%sAccepted: %u\n" + "%sNConnections: %u\n" + "%sMaxConnections: %u\n" + "%sMaxConnectionsPerSource: %u\n", + prefix, s->n_accepted, + prefix, s->n_connections, + prefix, s->max_connections, + prefix, s->max_connections_per_source); + + if (s->priority >= 0) + fprintf(f, + "%sPriority: %i\n", + prefix, s->priority); + + if (s->receive_buffer > 0) + fprintf(f, + "%sReceiveBuffer: %zu\n", + prefix, s->receive_buffer); + + if (s->send_buffer > 0) + fprintf(f, + "%sSendBuffer: %zu\n", + prefix, s->send_buffer); + + if (s->ip_tos >= 0) + fprintf(f, + "%sIPTOS: %i\n", + prefix, s->ip_tos); + + if (s->ip_ttl >= 0) + fprintf(f, + "%sIPTTL: %i\n", + prefix, s->ip_ttl); + + if (s->pipe_size > 0) + fprintf(f, + "%sPipeSize: %zu\n", + prefix, s->pipe_size); + + if (s->mark >= 0) + fprintf(f, + "%sMark: %i\n", + prefix, s->mark); + + if (s->mq_maxmsg > 0) + fprintf(f, + "%sMessageQueueMaxMessages: %li\n", + prefix, s->mq_maxmsg); + + if (s->mq_msgsize > 0) + fprintf(f, + "%sMessageQueueMessageSize: %li\n", + prefix, s->mq_msgsize); + + if (s->reuse_port) + fprintf(f, + "%sReusePort: %s\n", + prefix, yes_no(s->reuse_port)); + + if (s->smack) + fprintf(f, + "%sSmackLabel: %s\n", + prefix, s->smack); + + if (s->smack_ip_in) + fprintf(f, + "%sSmackLabelIPIn: %s\n", + prefix, s->smack_ip_in); + + if (s->smack_ip_out) + fprintf(f, + "%sSmackLabelIPOut: %s\n", + prefix, s->smack_ip_out); + + if (!isempty(s->user) || !isempty(s->group)) + fprintf(f, + "%sSocketUser: %s\n" + "%sSocketGroup: %s\n", + prefix, strna(s->user), + prefix, strna(s->group)); + + if (s->keep_alive_time > 0) + fprintf(f, + "%sKeepAliveTimeSec: %s\n", + prefix, format_timespan(time_string, FORMAT_TIMESPAN_MAX, s->keep_alive_time, USEC_PER_SEC)); + + if (s->keep_alive_interval > 0) + fprintf(f, + "%sKeepAliveIntervalSec: %s\n", + prefix, format_timespan(time_string, FORMAT_TIMESPAN_MAX, s->keep_alive_interval, USEC_PER_SEC)); + + if (s->keep_alive_cnt > 0) + fprintf(f, + "%sKeepAliveProbes: %u\n", + prefix, s->keep_alive_cnt); + + if (s->defer_accept > 0) + fprintf(f, + "%sDeferAcceptSec: %s\n", + prefix, format_timespan(time_string, FORMAT_TIMESPAN_MAX, s->defer_accept, USEC_PER_SEC)); + + LIST_FOREACH(port, p, s->ports) { + + switch (p->type) { + case SOCKET_SOCKET: { + _cleanup_free_ char *k = NULL; + const char *t; + int r; + + r = socket_address_print(&p->address, &k); + if (r < 0) + t = strerror(-r); + else + t = k; + + fprintf(f, "%s%s: %s\n", prefix, listen_lookup(socket_address_family(&p->address), p->address.type), t); + break; + } + case SOCKET_SPECIAL: + fprintf(f, "%sListenSpecial: %s\n", prefix, p->path); + break; + case SOCKET_USB_FUNCTION: + fprintf(f, "%sListenUSBFunction: %s\n", prefix, p->path); + break; + case SOCKET_MQUEUE: + fprintf(f, "%sListenMessageQueue: %s\n", prefix, p->path); + break; + default: + fprintf(f, "%sListenFIFO: %s\n", prefix, p->path); + } + } + + fprintf(f, + "%sTriggerLimitIntervalSec: %s\n" + "%sTriggerLimitBurst: %u\n", + prefix, format_timespan(time_string, FORMAT_TIMESPAN_MAX, s->trigger_limit.interval, USEC_PER_SEC), + prefix, s->trigger_limit.burst); + + str = ip_protocol_to_name(s->socket_protocol); + if (str) + fprintf(f, "%sSocketProtocol: %s\n", prefix, str); + + if (!strv_isempty(s->symlinks)) { + char **q; + + fprintf(f, "%sSymlinks:", prefix); + STRV_FOREACH(q, s->symlinks) + fprintf(f, " %s", *q); + + fprintf(f, "\n"); + } + + fprintf(f, + "%sTimeoutSec: %s\n", + prefix, format_timespan(time_string, FORMAT_TIMESPAN_MAX, s->timeout_usec, USEC_PER_SEC)); + + exec_context_dump(&s->exec_context, f, prefix); + kill_context_dump(&s->kill_context, f, prefix); + + for (c = 0; c < _SOCKET_EXEC_COMMAND_MAX; c++) { + if (!s->exec_command[c]) + continue; + + fprintf(f, "%s-> %s:\n", + prefix, socket_exec_command_to_string(c)); + + exec_command_dump_list(s->exec_command[c], f, prefix2); + } + + cgroup_context_dump(&s->cgroup_context, f, prefix); +} + +static int instance_from_socket(int fd, unsigned nr, char **instance) { + socklen_t l; + char *r; + union sockaddr_union local, remote; + + assert(fd >= 0); + assert(instance); + + l = sizeof(local); + if (getsockname(fd, &local.sa, &l) < 0) + return -errno; + + l = sizeof(remote); + if (getpeername(fd, &remote.sa, &l) < 0) + return -errno; + + switch (local.sa.sa_family) { + + case AF_INET: { + uint32_t + a = be32toh(local.in.sin_addr.s_addr), + b = be32toh(remote.in.sin_addr.s_addr); + + if (asprintf(&r, + "%u-%u.%u.%u.%u:%u-%u.%u.%u.%u:%u", + nr, + a >> 24, (a >> 16) & 0xFF, (a >> 8) & 0xFF, a & 0xFF, + be16toh(local.in.sin_port), + b >> 24, (b >> 16) & 0xFF, (b >> 8) & 0xFF, b & 0xFF, + be16toh(remote.in.sin_port)) < 0) + return -ENOMEM; + + break; + } + + case AF_INET6: { + static const unsigned char ipv4_prefix[] = { + 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0xFF, 0xFF + }; + + if (memcmp(&local.in6.sin6_addr, ipv4_prefix, sizeof(ipv4_prefix)) == 0 && + memcmp(&remote.in6.sin6_addr, ipv4_prefix, sizeof(ipv4_prefix)) == 0) { + const uint8_t + *a = local.in6.sin6_addr.s6_addr+12, + *b = remote.in6.sin6_addr.s6_addr+12; + + if (asprintf(&r, + "%u-%u.%u.%u.%u:%u-%u.%u.%u.%u:%u", + nr, + a[0], a[1], a[2], a[3], + be16toh(local.in6.sin6_port), + b[0], b[1], b[2], b[3], + be16toh(remote.in6.sin6_port)) < 0) + return -ENOMEM; + } else { + char a[INET6_ADDRSTRLEN], b[INET6_ADDRSTRLEN]; + + if (asprintf(&r, + "%u-%s:%u-%s:%u", + nr, + inet_ntop(AF_INET6, &local.in6.sin6_addr, a, sizeof(a)), + be16toh(local.in6.sin6_port), + inet_ntop(AF_INET6, &remote.in6.sin6_addr, b, sizeof(b)), + be16toh(remote.in6.sin6_port)) < 0) + return -ENOMEM; + } + + break; + } + + case AF_UNIX: { + struct ucred ucred; + int k; + + k = getpeercred(fd, &ucred); + if (k >= 0) { + if (asprintf(&r, + "%u-"PID_FMT"-"UID_FMT, + nr, ucred.pid, ucred.uid) < 0) + return -ENOMEM; + } else if (k == -ENODATA) { + /* This handles the case where somebody is + * connecting from another pid/uid namespace + * (e.g. from outside of our container). */ + if (asprintf(&r, + "%u-unknown", + nr) < 0) + return -ENOMEM; + } else + return k; + + break; + } + + case AF_VSOCK: + if (asprintf(&r, + "%u-%u:%u-%u:%u", + nr, + local.vm.svm_cid, local.vm.svm_port, + remote.vm.svm_cid, remote.vm.svm_port) < 0) + return -ENOMEM; + + break; + + default: + assert_not_reached("Unhandled socket type."); + } + + *instance = r; + return 0; +} + +static void socket_close_fds(Socket *s) { + SocketPort *p; + char **i; + + assert(s); + + LIST_FOREACH(port, p, s->ports) { + bool was_open; + + was_open = p->fd >= 0; + + p->event_source = sd_event_source_unref(p->event_source); + p->fd = safe_close(p->fd); + socket_cleanup_fd_list(p); + + /* One little note: we should normally not delete any sockets in the file system here! After all some + * other process we spawned might still have a reference of this fd and wants to continue to use + * it. Therefore we normally delete sockets in the file system before we create a new one, not after we + * stopped using one! That all said, if the user explicitly requested this, we'll delete them here + * anyway, but only then. */ + + if (!was_open || !s->remove_on_stop) + continue; + + switch (p->type) { + + case SOCKET_FIFO: + (void) unlink(p->path); + break; + + case SOCKET_MQUEUE: + (void) mq_unlink(p->path); + break; + + case SOCKET_SOCKET: + (void) socket_address_unlink(&p->address); + break; + + default: + break; + } + } + + if (s->remove_on_stop) + STRV_FOREACH(i, s->symlinks) + (void) unlink(*i); +} + +static void socket_apply_socket_options(Socket *s, int fd) { + int r; + + assert(s); + assert(fd >= 0); + + if (s->keep_alive) { + r = setsockopt_int(fd, SOL_SOCKET, SO_KEEPALIVE, true); + if (r < 0) + log_unit_warning_errno(UNIT(s), r, "SO_KEEPALIVE failed: %m"); + } + + if (s->keep_alive_time > 0) { + r = setsockopt_int(fd, SOL_TCP, TCP_KEEPIDLE, s->keep_alive_time / USEC_PER_SEC); + if (r < 0) + log_unit_warning_errno(UNIT(s), r, "TCP_KEEPIDLE failed: %m"); + } + + if (s->keep_alive_interval > 0) { + r = setsockopt_int(fd, SOL_TCP, TCP_KEEPINTVL, s->keep_alive_interval / USEC_PER_SEC); + if (r < 0) + log_unit_warning_errno(UNIT(s), r, "TCP_KEEPINTVL failed: %m"); + } + + if (s->keep_alive_cnt > 0) { + r = setsockopt_int(fd, SOL_TCP, TCP_KEEPCNT, s->keep_alive_cnt); + if (r < 0) + log_unit_warning_errno(UNIT(s), r, "TCP_KEEPCNT failed: %m"); + } + + if (s->defer_accept > 0) { + r = setsockopt_int(fd, SOL_TCP, TCP_DEFER_ACCEPT, s->defer_accept / USEC_PER_SEC); + if (r < 0) + log_unit_warning_errno(UNIT(s), r, "TCP_DEFER_ACCEPT failed: %m"); + } + + if (s->no_delay) { + if (s->socket_protocol == IPPROTO_SCTP) { + r = setsockopt_int(fd, SOL_SCTP, SCTP_NODELAY, true); + if (r < 0) + log_unit_warning_errno(UNIT(s), r, "SCTP_NODELAY failed: %m"); + } else { + r = setsockopt_int(fd, SOL_TCP, TCP_NODELAY, true); + if (r < 0) + log_unit_warning_errno(UNIT(s), r, "TCP_NODELAY failed: %m"); + } + } + + if (s->broadcast) { + r = setsockopt_int(fd, SOL_SOCKET, SO_BROADCAST, true); + if (r < 0) + log_unit_warning_errno(UNIT(s), r, "SO_BROADCAST failed: %m"); + } + + if (s->pass_cred) { + r = setsockopt_int(fd, SOL_SOCKET, SO_PASSCRED, true); + if (r < 0) + log_unit_warning_errno(UNIT(s), r, "SO_PASSCRED failed: %m"); + } + + if (s->pass_sec) { + r = setsockopt_int(fd, SOL_SOCKET, SO_PASSSEC, true); + if (r < 0) + log_unit_warning_errno(UNIT(s), r, "SO_PASSSEC failed: %m"); + } + + if (s->priority >= 0) { + r = setsockopt_int(fd, SOL_SOCKET, SO_PRIORITY, s->priority); + if (r < 0) + log_unit_warning_errno(UNIT(s), r, "SO_PRIORITY failed: %m"); + } + + if (s->receive_buffer > 0) { + /* We first try with SO_RCVBUFFORCE, in case we have the perms for that */ + if (setsockopt_int(fd, SOL_SOCKET, SO_RCVBUFFORCE, s->receive_buffer) < 0) { + r = setsockopt_int(fd, SOL_SOCKET, SO_RCVBUF, s->receive_buffer); + if (r < 0) + log_unit_warning_errno(UNIT(s), r, "SO_RCVBUF failed: %m"); + } + } + + if (s->send_buffer > 0) { + if (setsockopt_int(fd, SOL_SOCKET, SO_SNDBUFFORCE, s->send_buffer) < 0) { + r = setsockopt_int(fd, SOL_SOCKET, SO_SNDBUF, s->send_buffer); + if (r < 0) + log_unit_warning_errno(UNIT(s), r, "SO_SNDBUF failed: %m"); + } + } + + if (s->mark >= 0) { + r = setsockopt_int(fd, SOL_SOCKET, SO_MARK, s->mark); + if (r < 0) + log_unit_warning_errno(UNIT(s), r, "SO_MARK failed: %m"); + } + + if (s->ip_tos >= 0) { + r = setsockopt_int(fd, IPPROTO_IP, IP_TOS, s->ip_tos); + if (r < 0) + log_unit_warning_errno(UNIT(s), r, "IP_TOS failed: %m"); + } + + if (s->ip_ttl >= 0) { + int x; + + r = setsockopt_int(fd, IPPROTO_IP, IP_TTL, s->ip_ttl); + + if (socket_ipv6_is_supported()) + x = setsockopt_int(fd, IPPROTO_IPV6, IPV6_UNICAST_HOPS, s->ip_ttl); + else + x = -EAFNOSUPPORT; + + if (r < 0 && x < 0) + log_unit_warning_errno(UNIT(s), r, "IP_TTL/IPV6_UNICAST_HOPS failed: %m"); + } + + if (s->tcp_congestion) + if (setsockopt(fd, SOL_TCP, TCP_CONGESTION, s->tcp_congestion, strlen(s->tcp_congestion)+1) < 0) + log_unit_warning_errno(UNIT(s), errno, "TCP_CONGESTION failed: %m"); + + if (s->smack_ip_in) { + r = mac_smack_apply_fd(fd, SMACK_ATTR_IPIN, s->smack_ip_in); + if (r < 0) + log_unit_error_errno(UNIT(s), r, "mac_smack_apply_ip_in_fd: %m"); + } + + if (s->smack_ip_out) { + r = mac_smack_apply_fd(fd, SMACK_ATTR_IPOUT, s->smack_ip_out); + if (r < 0) + log_unit_error_errno(UNIT(s), r, "mac_smack_apply_ip_out_fd: %m"); + } +} + +static void socket_apply_fifo_options(Socket *s, int fd) { + int r; + + assert(s); + assert(fd >= 0); + + if (s->pipe_size > 0) + if (fcntl(fd, F_SETPIPE_SZ, s->pipe_size) < 0) + log_unit_warning_errno(UNIT(s), errno, "Setting pipe size failed, ignoring: %m"); + + if (s->smack) { + r = mac_smack_apply_fd(fd, SMACK_ATTR_ACCESS, s->smack); + if (r < 0) + log_unit_error_errno(UNIT(s), r, "SMACK relabelling failed, ignoring: %m"); + } +} + +static int fifo_address_create( + const char *path, + mode_t directory_mode, + mode_t socket_mode) { + + _cleanup_close_ int fd = -1; + mode_t old_mask; + struct stat st; + int r; + + assert(path); + + (void) mkdir_parents_label(path, directory_mode); + + r = mac_selinux_create_file_prepare(path, S_IFIFO); + if (r < 0) + return r; + + /* Enforce the right access mode for the fifo */ + old_mask = umask(~socket_mode); + + /* Include the original umask in our mask */ + (void) umask(~socket_mode | old_mask); + + r = mkfifo(path, socket_mode); + (void) umask(old_mask); + + if (r < 0 && errno != EEXIST) { + r = -errno; + goto fail; + } + + fd = open(path, O_RDWR | O_CLOEXEC | O_NOCTTY | O_NONBLOCK | O_NOFOLLOW); + if (fd < 0) { + r = -errno; + goto fail; + } + + mac_selinux_create_file_clear(); + + if (fstat(fd, &st) < 0) { + r = -errno; + goto fail; + } + + if (!S_ISFIFO(st.st_mode) || + (st.st_mode & 0777) != (socket_mode & ~old_mask) || + st.st_uid != getuid() || + st.st_gid != getgid()) { + r = -EEXIST; + goto fail; + } + + return TAKE_FD(fd); + +fail: + mac_selinux_create_file_clear(); + return r; +} + +static int special_address_create(const char *path, bool writable) { + _cleanup_close_ int fd = -1; + struct stat st; + + assert(path); + + fd = open(path, (writable ? O_RDWR : O_RDONLY)|O_CLOEXEC|O_NOCTTY|O_NONBLOCK|O_NOFOLLOW); + if (fd < 0) + return -errno; + + if (fstat(fd, &st) < 0) + return -errno; + + /* Check whether this is a /proc, /sys or /dev file or char device */ + if (!S_ISREG(st.st_mode) && !S_ISCHR(st.st_mode)) + return -EEXIST; + + return TAKE_FD(fd); +} + +static int usbffs_address_create(const char *path) { + _cleanup_close_ int fd = -1; + struct stat st; + + assert(path); + + fd = open(path, O_RDWR|O_CLOEXEC|O_NOCTTY|O_NONBLOCK|O_NOFOLLOW); + if (fd < 0) + return -errno; + + if (fstat(fd, &st) < 0) + return -errno; + + /* Check whether this is a regular file (ffs endpoint) */ + if (!S_ISREG(st.st_mode)) + return -EEXIST; + + return TAKE_FD(fd); +} + +static int mq_address_create( + const char *path, + mode_t mq_mode, + long maxmsg, + long msgsize) { + + _cleanup_close_ int fd = -1; + struct stat st; + mode_t old_mask; + struct mq_attr _attr, *attr = NULL; + + assert(path); + + if (maxmsg > 0 && msgsize > 0) { + _attr = (struct mq_attr) { + .mq_flags = O_NONBLOCK, + .mq_maxmsg = maxmsg, + .mq_msgsize = msgsize, + }; + attr = &_attr; + } + + /* Enforce the right access mode for the mq */ + old_mask = umask(~mq_mode); + + /* Include the original umask in our mask */ + (void) umask(~mq_mode | old_mask); + fd = mq_open(path, O_RDONLY|O_CLOEXEC|O_NONBLOCK|O_CREAT, mq_mode, attr); + (void) umask(old_mask); + + if (fd < 0) + return -errno; + + if (fstat(fd, &st) < 0) + return -errno; + + if ((st.st_mode & 0777) != (mq_mode & ~old_mask) || + st.st_uid != getuid() || + st.st_gid != getgid()) + return -EEXIST; + + return TAKE_FD(fd); +} + +static int socket_symlink(Socket *s) { + const char *p; + char **i; + int r; + + assert(s); + + p = socket_find_symlink_target(s); + if (!p) + return 0; + + STRV_FOREACH(i, s->symlinks) { + (void) mkdir_parents_label(*i, s->directory_mode); + + r = symlink_idempotent(p, *i, false); + + if (r == -EEXIST && s->remove_on_stop) { + /* If there's already something where we want to create the symlink, and the destructive + * RemoveOnStop= mode is set, then we might as well try to remove what already exists and try + * again. */ + + if (unlink(*i) >= 0) + r = symlink_idempotent(p, *i, false); + } + + if (r < 0) + log_unit_warning_errno(UNIT(s), r, "Failed to create symlink %s → %s, ignoring: %m", p, *i); + } + + return 0; +} + +static int usbffs_write_descs(int fd, Service *s) { + int r; + + if (!s->usb_function_descriptors || !s->usb_function_strings) + return -EINVAL; + + r = copy_file_fd(s->usb_function_descriptors, fd, 0); + if (r < 0) + return r; + + return copy_file_fd(s->usb_function_strings, fd, 0); +} + +static int usbffs_select_ep(const struct dirent *d) { + return d->d_name[0] != '.' && !streq(d->d_name, "ep0"); +} + +static int usbffs_dispatch_eps(SocketPort *p) { + _cleanup_free_ struct dirent **ent = NULL; + size_t n, k, i; + int r; + + r = scandir(p->path, &ent, usbffs_select_ep, alphasort); + if (r < 0) + return -errno; + + n = (size_t) r; + p->auxiliary_fds = new(int, n); + if (!p->auxiliary_fds) { + r = -ENOMEM; + goto clear; + } + + p->n_auxiliary_fds = n; + + k = 0; + for (i = 0; i < n; ++i) { + _cleanup_free_ char *ep = NULL; + + ep = path_make_absolute(ent[i]->d_name, p->path); + if (!ep) { + r = -ENOMEM; + goto fail; + } + + path_simplify(ep, false); + + r = usbffs_address_create(ep); + if (r < 0) + goto fail; + + p->auxiliary_fds[k++] = r; + } + + r = 0; + goto clear; + +fail: + close_many(p->auxiliary_fds, k); + p->auxiliary_fds = mfree(p->auxiliary_fds); + p->n_auxiliary_fds = 0; + +clear: + for (i = 0; i < n; ++i) + free(ent[i]); + + return r; +} + +static int socket_determine_selinux_label(Socket *s, char **ret) { + Service *service; + ExecCommand *c; + _cleanup_free_ char *path = NULL; + int r; + + assert(s); + assert(ret); + + if (s->selinux_context_from_net) { + /* If this is requested, get label from the network label */ + + r = mac_selinux_get_our_label(ret); + if (r == -EOPNOTSUPP) + goto no_label; + + } else { + /* Otherwise, get it from the executable we are about to start */ + r = socket_instantiate_service(s); + if (r < 0) + return r; + + if (!UNIT_ISSET(s->service)) + goto no_label; + + service = SERVICE(UNIT_DEREF(s->service)); + c = service->exec_command[SERVICE_EXEC_START]; + if (!c) + goto no_label; + + r = chase_symlinks(c->path, service->exec_context.root_directory, CHASE_PREFIX_ROOT, &path); + if (r < 0) + goto no_label; + + r = mac_selinux_get_create_label_from_exe(path, ret); + if (IN_SET(r, -EPERM, -EOPNOTSUPP)) + goto no_label; + } + + return r; + +no_label: + *ret = NULL; + return 0; +} + +static int socket_address_listen_do( + Socket *s, + const SocketAddress *address, + const char *label) { + + assert(s); + assert(address); + + return socket_address_listen( + address, + SOCK_CLOEXEC|SOCK_NONBLOCK, + s->backlog, + s->bind_ipv6_only, + s->bind_to_device, + s->reuse_port, + s->free_bind, + s->transparent, + s->directory_mode, + s->socket_mode, + label); +} + +#define log_address_error_errno(u, address, error, fmt) \ + ({ \ + _cleanup_free_ char *_t = NULL; \ + \ + (void) socket_address_print(address, &_t); \ + log_unit_error_errno(u, error, fmt, strna(_t)); \ + }) + +static int socket_address_listen_in_cgroup( + Socket *s, + const SocketAddress *address, + const char *label) { + + _cleanup_close_pair_ int pair[2] = { -1, -1 }; + int fd, r; + pid_t pid; + + assert(s); + assert(address); + + /* This is a wrapper around socket_address_listen(), that forks off a helper process inside the socket's cgroup + * in which the socket is actually created. This way we ensure the socket is actually properly attached to the + * unit's cgroup for the purpose of BPF filtering and such. */ + + if (!IN_SET(address->sockaddr.sa.sa_family, AF_INET, AF_INET6)) + goto shortcut; /* BPF filtering only applies to IPv4 + IPv6, shortcut things for other protocols */ + + r = bpf_firewall_supported(); + if (r < 0) + return r; + if (r == BPF_FIREWALL_UNSUPPORTED) /* If BPF firewalling isn't supported anyway — there's no point in this forking complexity */ + goto shortcut; + + if (socketpair(AF_UNIX, SOCK_SEQPACKET|SOCK_CLOEXEC, 0, pair) < 0) + return log_unit_error_errno(UNIT(s), errno, "Failed to create communication channel: %m"); + + r = unit_fork_helper_process(UNIT(s), "(sd-listen)", &pid); + if (r < 0) + return log_unit_error_errno(UNIT(s), r, "Failed to fork off listener stub process: %m"); + if (r == 0) { + /* Child */ + + pair[0] = safe_close(pair[0]); + + fd = socket_address_listen_do(s, address, label); + if (fd < 0) { + log_address_error_errno(UNIT(s), address, fd, "Failed to create listening socket (%s): %m"); + _exit(EXIT_FAILURE); + } + + r = send_one_fd(pair[1], fd, 0); + if (r < 0) { + log_address_error_errno(UNIT(s), address, r, "Failed to send listening socket (%s) to parent: %m"); + _exit(EXIT_FAILURE); + } + + _exit(EXIT_SUCCESS); + } + + pair[1] = safe_close(pair[1]); + fd = receive_one_fd(pair[0], 0); + + /* We synchronously wait for the helper, as it shouldn't be slow */ + r = wait_for_terminate_and_check("(sd-listen)", pid, WAIT_LOG_ABNORMAL); + if (r < 0) { + safe_close(fd); + return r; + } + + if (fd < 0) + return log_address_error_errno(UNIT(s), address, fd, "Failed to receive listening socket (%s): %m"); + + return fd; + +shortcut: + fd = socket_address_listen_do(s, address, label); + if (fd < 0) + return log_address_error_errno(UNIT(s), address, fd, "Failed to create listening socket (%s): %m"); + + return fd; +} + +DEFINE_TRIVIAL_CLEANUP_FUNC(Socket *, socket_close_fds); + +static int socket_open_fds(Socket *_s) { + _cleanup_(socket_close_fdsp) Socket *s = _s; + _cleanup_(mac_selinux_freep) char *label = NULL; + bool know_label = false; + SocketPort *p; + int r; + + assert(s); + + LIST_FOREACH(port, p, s->ports) { + + if (p->fd >= 0) + continue; + + switch (p->type) { + + case SOCKET_SOCKET: + + if (!know_label) { + /* Figure out label, if we don't it know yet. We do it once, for the first socket where + * we need this and remember it for the rest. */ + + r = socket_determine_selinux_label(s, &label); + if (r < 0) + return log_unit_error_errno(UNIT(s), r, "Failed to determine SELinux label: %m"); + + know_label = true; + } + + /* Apply the socket protocol */ + switch (p->address.type) { + + case SOCK_STREAM: + case SOCK_SEQPACKET: + if (s->socket_protocol == IPPROTO_SCTP) + p->address.protocol = s->socket_protocol; + break; + + case SOCK_DGRAM: + if (s->socket_protocol == IPPROTO_UDPLITE) + p->address.protocol = s->socket_protocol; + break; + } + + p->fd = socket_address_listen_in_cgroup(s, &p->address, label); + if (p->fd < 0) + return p->fd; + + socket_apply_socket_options(s, p->fd); + socket_symlink(s); + break; + + case SOCKET_SPECIAL: + + p->fd = special_address_create(p->path, s->writable); + if (p->fd < 0) + return log_unit_error_errno(UNIT(s), p->fd, "Failed to open special file %s: %m", p->path); + break; + + case SOCKET_FIFO: + + p->fd = fifo_address_create( + p->path, + s->directory_mode, + s->socket_mode); + if (p->fd < 0) + return log_unit_error_errno(UNIT(s), p->fd, "Failed to open FIFO %s: %m", p->path); + + socket_apply_fifo_options(s, p->fd); + socket_symlink(s); + break; + + case SOCKET_MQUEUE: + + p->fd = mq_address_create( + p->path, + s->socket_mode, + s->mq_maxmsg, + s->mq_msgsize); + if (p->fd < 0) + return log_unit_error_errno(UNIT(s), p->fd, "Failed to open message queue %s: %m", p->path); + break; + + case SOCKET_USB_FUNCTION: { + _cleanup_free_ char *ep = NULL; + + ep = path_make_absolute("ep0", p->path); + + p->fd = usbffs_address_create(ep); + if (p->fd < 0) + return p->fd; + + r = usbffs_write_descs(p->fd, SERVICE(UNIT_DEREF(s->service))); + if (r < 0) + return r; + + r = usbffs_dispatch_eps(p); + if (r < 0) + return r; + + break; + } + default: + assert_not_reached("Unknown port type"); + } + } + + s = NULL; + return 0; +} + +static void socket_unwatch_fds(Socket *s) { + SocketPort *p; + int r; + + assert(s); + + LIST_FOREACH(port, p, s->ports) { + if (p->fd < 0) + continue; + + if (!p->event_source) + continue; + + r = sd_event_source_set_enabled(p->event_source, SD_EVENT_OFF); + if (r < 0) + log_unit_debug_errno(UNIT(s), r, "Failed to disable event source: %m"); + } +} + +static int socket_watch_fds(Socket *s) { + SocketPort *p; + int r; + + assert(s); + + LIST_FOREACH(port, p, s->ports) { + if (p->fd < 0) + continue; + + if (p->event_source) { + r = sd_event_source_set_enabled(p->event_source, SD_EVENT_ON); + if (r < 0) + goto fail; + } else { + r = sd_event_add_io(UNIT(s)->manager->event, &p->event_source, p->fd, EPOLLIN, socket_dispatch_io, p); + if (r < 0) + goto fail; + + (void) sd_event_source_set_description(p->event_source, "socket-port-io"); + } + } + + return 0; + +fail: + log_unit_warning_errno(UNIT(s), r, "Failed to watch listening fds: %m"); + socket_unwatch_fds(s); + return r; +} + +enum { + SOCKET_OPEN_NONE, + SOCKET_OPEN_SOME, + SOCKET_OPEN_ALL, +}; + +static int socket_check_open(Socket *s) { + bool have_open = false, have_closed = false; + SocketPort *p; + + assert(s); + + LIST_FOREACH(port, p, s->ports) { + if (p->fd < 0) + have_closed = true; + else + have_open = true; + + if (have_open && have_closed) + return SOCKET_OPEN_SOME; + } + + if (have_open) + return SOCKET_OPEN_ALL; + + return SOCKET_OPEN_NONE; +} + +static void socket_set_state(Socket *s, SocketState state) { + SocketState old_state; + assert(s); + + if (s->state != state) + bus_unit_send_pending_change_signal(UNIT(s), false); + + old_state = s->state; + s->state = state; + + if (!IN_SET(state, + SOCKET_START_PRE, + SOCKET_START_CHOWN, + SOCKET_START_POST, + SOCKET_STOP_PRE, + SOCKET_STOP_PRE_SIGTERM, + SOCKET_STOP_PRE_SIGKILL, + SOCKET_STOP_POST, + SOCKET_FINAL_SIGTERM, + SOCKET_FINAL_SIGKILL)) { + + s->timer_event_source = sd_event_source_unref(s->timer_event_source); + socket_unwatch_control_pid(s); + s->control_command = NULL; + s->control_command_id = _SOCKET_EXEC_COMMAND_INVALID; + } + + if (state != SOCKET_LISTENING) + socket_unwatch_fds(s); + + if (!IN_SET(state, + SOCKET_START_CHOWN, + SOCKET_START_POST, + SOCKET_LISTENING, + SOCKET_RUNNING, + SOCKET_STOP_PRE, + SOCKET_STOP_PRE_SIGTERM, + SOCKET_STOP_PRE_SIGKILL)) + socket_close_fds(s); + + if (state != old_state) + log_unit_debug(UNIT(s), "Changed %s -> %s", socket_state_to_string(old_state), socket_state_to_string(state)); + + unit_notify(UNIT(s), state_translation_table[old_state], state_translation_table[state], 0); +} + +static int socket_coldplug(Unit *u) { + Socket *s = SOCKET(u); + int r; + + assert(s); + assert(s->state == SOCKET_DEAD); + + if (s->deserialized_state == s->state) + return 0; + + if (s->control_pid > 0 && + pid_is_unwaited(s->control_pid) && + IN_SET(s->deserialized_state, + SOCKET_START_PRE, + SOCKET_START_CHOWN, + SOCKET_START_POST, + SOCKET_STOP_PRE, + SOCKET_STOP_PRE_SIGTERM, + SOCKET_STOP_PRE_SIGKILL, + SOCKET_STOP_POST, + SOCKET_FINAL_SIGTERM, + SOCKET_FINAL_SIGKILL)) { + + r = unit_watch_pid(UNIT(s), s->control_pid); + if (r < 0) + return r; + + r = socket_arm_timer(s, usec_add(u->state_change_timestamp.monotonic, s->timeout_usec)); + if (r < 0) + return r; + } + + if (IN_SET(s->deserialized_state, + SOCKET_START_CHOWN, + SOCKET_START_POST, + SOCKET_LISTENING, + SOCKET_RUNNING)) { + + /* Originally, we used to simply reopen all sockets here that we didn't have file descriptors + * for. However, this is problematic, as we won't traverse throught the SOCKET_START_CHOWN state for + * them, and thus the UID/GID wouldn't be right. Hence, instead simply check if we have all fds open, + * and if there's a mismatch, warn loudly. */ + + r = socket_check_open(s); + if (r == SOCKET_OPEN_NONE) + log_unit_warning(UNIT(s), + "Socket unit configuration has changed while unit has been running, " + "no open socket file descriptor left. " + "The socket unit is not functional until restarted."); + else if (r == SOCKET_OPEN_SOME) + log_unit_warning(UNIT(s), + "Socket unit configuration has changed while unit has been running, " + "and some socket file descriptors have not been opened yet. " + "The socket unit is not fully functional until restarted."); + } + + if (s->deserialized_state == SOCKET_LISTENING) { + r = socket_watch_fds(s); + if (r < 0) + return r; + } + + if (!IN_SET(s->deserialized_state, SOCKET_DEAD, SOCKET_FAILED)) { + (void) unit_setup_dynamic_creds(u); + (void) unit_setup_exec_runtime(u); + } + + socket_set_state(s, s->deserialized_state); + return 0; +} + +static int socket_spawn(Socket *s, ExecCommand *c, pid_t *_pid) { + + _cleanup_(exec_params_clear) ExecParameters exec_params = { + .flags = EXEC_APPLY_SANDBOXING|EXEC_APPLY_CHROOT|EXEC_APPLY_TTY_STDIN, + .stdin_fd = -1, + .stdout_fd = -1, + .stderr_fd = -1, + .exec_fd = -1, + }; + pid_t pid; + int r; + + assert(s); + assert(c); + assert(_pid); + + r = unit_prepare_exec(UNIT(s)); + if (r < 0) + return r; + + r = socket_arm_timer(s, usec_add(now(CLOCK_MONOTONIC), s->timeout_usec)); + if (r < 0) + return r; + + r = unit_set_exec_params(UNIT(s), &exec_params); + if (r < 0) + return r; + + r = exec_spawn(UNIT(s), + c, + &s->exec_context, + &exec_params, + s->exec_runtime, + &s->dynamic_creds, + &pid); + if (r < 0) + return r; + + r = unit_watch_pid(UNIT(s), pid); + if (r < 0) + /* FIXME: we need to do something here */ + return r; + + *_pid = pid; + + return 0; +} + +static int socket_chown(Socket *s, pid_t *_pid) { + pid_t pid; + int r; + + r = socket_arm_timer(s, usec_add(now(CLOCK_MONOTONIC), s->timeout_usec)); + if (r < 0) + goto fail; + + /* We have to resolve the user names out-of-process, hence + * let's fork here. It's messy, but well, what can we do? */ + + r = unit_fork_helper_process(UNIT(s), "(sd-chown)", &pid); + if (r < 0) + return r; + if (r == 0) { + uid_t uid = UID_INVALID; + gid_t gid = GID_INVALID; + SocketPort *p; + + /* Child */ + + if (!isempty(s->user)) { + const char *user = s->user; + + r = get_user_creds(&user, &uid, &gid, NULL, NULL, 0); + if (r < 0) { + log_unit_error_errno(UNIT(s), r, "Failed to resolve user %s: %m", user); + _exit(EXIT_USER); + } + } + + if (!isempty(s->group)) { + const char *group = s->group; + + r = get_group_creds(&group, &gid, 0); + if (r < 0) { + log_unit_error_errno(UNIT(s), r, "Failed to resolve group %s: %m", group); + _exit(EXIT_GROUP); + } + } + + LIST_FOREACH(port, p, s->ports) { + const char *path = NULL; + + if (p->type == SOCKET_SOCKET) + path = socket_address_get_path(&p->address); + else if (p->type == SOCKET_FIFO) + path = p->path; + + if (!path) + continue; + + if (chown(path, uid, gid) < 0) { + log_unit_error_errno(UNIT(s), errno, "Failed to chown(): %m"); + _exit(EXIT_CHOWN); + } + } + + _exit(EXIT_SUCCESS); + } + + r = unit_watch_pid(UNIT(s), pid); + if (r < 0) + goto fail; + + *_pid = pid; + return 0; + +fail: + s->timer_event_source = sd_event_source_unref(s->timer_event_source); + return r; +} + +static void socket_enter_dead(Socket *s, SocketResult f) { + assert(s); + + if (s->result == SOCKET_SUCCESS) + s->result = f; + + if (s->result == SOCKET_SUCCESS) + unit_log_success(UNIT(s)); + else + unit_log_failure(UNIT(s), socket_result_to_string(s->result)); + + socket_set_state(s, s->result != SOCKET_SUCCESS ? SOCKET_FAILED : SOCKET_DEAD); + + s->exec_runtime = exec_runtime_unref(s->exec_runtime, true); + + exec_context_destroy_runtime_directory(&s->exec_context, UNIT(s)->manager->prefix[EXEC_DIRECTORY_RUNTIME]); + + unit_unref_uid_gid(UNIT(s), true); + + dynamic_creds_destroy(&s->dynamic_creds); +} + +static void socket_enter_signal(Socket *s, SocketState state, SocketResult f); + +static void socket_enter_stop_post(Socket *s, SocketResult f) { + int r; + assert(s); + + if (s->result == SOCKET_SUCCESS) + s->result = f; + + socket_unwatch_control_pid(s); + s->control_command_id = SOCKET_EXEC_STOP_POST; + s->control_command = s->exec_command[SOCKET_EXEC_STOP_POST]; + + if (s->control_command) { + r = socket_spawn(s, s->control_command, &s->control_pid); + if (r < 0) + goto fail; + + socket_set_state(s, SOCKET_STOP_POST); + } else + socket_enter_signal(s, SOCKET_FINAL_SIGTERM, SOCKET_SUCCESS); + + return; + +fail: + log_unit_warning_errno(UNIT(s), r, "Failed to run 'stop-post' task: %m"); + socket_enter_signal(s, SOCKET_FINAL_SIGTERM, SOCKET_FAILURE_RESOURCES); +} + +static void socket_enter_signal(Socket *s, SocketState state, SocketResult f) { + int r; + + assert(s); + + if (s->result == SOCKET_SUCCESS) + s->result = f; + + r = unit_kill_context( + UNIT(s), + &s->kill_context, + !IN_SET(state, SOCKET_STOP_PRE_SIGTERM, SOCKET_FINAL_SIGTERM) ? + KILL_KILL : KILL_TERMINATE, + -1, + s->control_pid, + false); + if (r < 0) + goto fail; + + if (r > 0) { + r = socket_arm_timer(s, usec_add(now(CLOCK_MONOTONIC), s->timeout_usec)); + if (r < 0) + goto fail; + + socket_set_state(s, state); + } else if (state == SOCKET_STOP_PRE_SIGTERM) + socket_enter_signal(s, SOCKET_STOP_PRE_SIGKILL, SOCKET_SUCCESS); + else if (state == SOCKET_STOP_PRE_SIGKILL) + socket_enter_stop_post(s, SOCKET_SUCCESS); + else if (state == SOCKET_FINAL_SIGTERM) + socket_enter_signal(s, SOCKET_FINAL_SIGKILL, SOCKET_SUCCESS); + else + socket_enter_dead(s, SOCKET_SUCCESS); + + return; + +fail: + log_unit_warning_errno(UNIT(s), r, "Failed to kill processes: %m"); + + if (IN_SET(state, SOCKET_STOP_PRE_SIGTERM, SOCKET_STOP_PRE_SIGKILL)) + socket_enter_stop_post(s, SOCKET_FAILURE_RESOURCES); + else + socket_enter_dead(s, SOCKET_FAILURE_RESOURCES); +} + +static void socket_enter_stop_pre(Socket *s, SocketResult f) { + int r; + assert(s); + + if (s->result == SOCKET_SUCCESS) + s->result = f; + + socket_unwatch_control_pid(s); + s->control_command_id = SOCKET_EXEC_STOP_PRE; + s->control_command = s->exec_command[SOCKET_EXEC_STOP_PRE]; + + if (s->control_command) { + r = socket_spawn(s, s->control_command, &s->control_pid); + if (r < 0) + goto fail; + + socket_set_state(s, SOCKET_STOP_PRE); + } else + socket_enter_stop_post(s, SOCKET_SUCCESS); + + return; + +fail: + log_unit_warning_errno(UNIT(s), r, "Failed to run 'stop-pre' task: %m"); + socket_enter_stop_post(s, SOCKET_FAILURE_RESOURCES); +} + +static void socket_enter_listening(Socket *s) { + int r; + assert(s); + + r = socket_watch_fds(s); + if (r < 0) { + log_unit_warning_errno(UNIT(s), r, "Failed to watch sockets: %m"); + goto fail; + } + + socket_set_state(s, SOCKET_LISTENING); + return; + +fail: + socket_enter_stop_pre(s, SOCKET_FAILURE_RESOURCES); +} + +static void socket_enter_start_post(Socket *s) { + int r; + assert(s); + + socket_unwatch_control_pid(s); + s->control_command_id = SOCKET_EXEC_START_POST; + s->control_command = s->exec_command[SOCKET_EXEC_START_POST]; + + if (s->control_command) { + r = socket_spawn(s, s->control_command, &s->control_pid); + if (r < 0) { + log_unit_warning_errno(UNIT(s), r, "Failed to run 'start-post' task: %m"); + goto fail; + } + + socket_set_state(s, SOCKET_START_POST); + } else + socket_enter_listening(s); + + return; + +fail: + socket_enter_stop_pre(s, SOCKET_FAILURE_RESOURCES); +} + +static void socket_enter_start_chown(Socket *s) { + int r; + + assert(s); + + r = socket_open_fds(s); + if (r < 0) { + log_unit_warning_errno(UNIT(s), r, "Failed to listen on sockets: %m"); + goto fail; + } + + if (!isempty(s->user) || !isempty(s->group)) { + + socket_unwatch_control_pid(s); + s->control_command_id = SOCKET_EXEC_START_CHOWN; + s->control_command = NULL; + + r = socket_chown(s, &s->control_pid); + if (r < 0) { + log_unit_warning_errno(UNIT(s), r, "Failed to fork 'start-chown' task: %m"); + goto fail; + } + + socket_set_state(s, SOCKET_START_CHOWN); + } else + socket_enter_start_post(s); + + return; + +fail: + socket_enter_stop_pre(s, SOCKET_FAILURE_RESOURCES); +} + +static void socket_enter_start_pre(Socket *s) { + int r; + assert(s); + + socket_unwatch_control_pid(s); + + unit_warn_leftover_processes(UNIT(s)); + + s->control_command_id = SOCKET_EXEC_START_PRE; + s->control_command = s->exec_command[SOCKET_EXEC_START_PRE]; + + if (s->control_command) { + r = socket_spawn(s, s->control_command, &s->control_pid); + if (r < 0) { + log_unit_warning_errno(UNIT(s), r, "Failed to run 'start-pre' task: %m"); + goto fail; + } + + socket_set_state(s, SOCKET_START_PRE); + } else + socket_enter_start_chown(s); + + return; + +fail: + socket_enter_dead(s, SOCKET_FAILURE_RESOURCES); +} + +static void flush_ports(Socket *s) { + SocketPort *p; + + /* Flush all incoming traffic, regardless if actual bytes or new connections, so that this socket isn't busy + * anymore */ + + LIST_FOREACH(port, p, s->ports) { + if (p->fd < 0) + continue; + + (void) flush_accept(p->fd); + (void) flush_fd(p->fd); + } +} + +static void socket_enter_running(Socket *s, int cfd) { + _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL; + int r; + + /* Note that this call takes possession of the connection fd passed. It either has to assign it somewhere or + * close it. */ + + assert(s); + + /* We don't take connections anymore if we are supposed to shut down anyway */ + if (unit_stop_pending(UNIT(s))) { + + log_unit_debug(UNIT(s), "Suppressing connection request since unit stop is scheduled."); + + if (cfd >= 0) + goto refuse; + else + flush_ports(s); + + return; + } + + if (!ratelimit_below(&s->trigger_limit)) { + log_unit_warning(UNIT(s), "Trigger limit hit, refusing further activation."); + socket_enter_stop_pre(s, SOCKET_FAILURE_TRIGGER_LIMIT_HIT); + goto refuse; + } + + if (cfd < 0) { + bool pending = false; + Unit *other; + Iterator i; + void *v; + + /* If there's already a start pending don't bother to + * do anything */ + HASHMAP_FOREACH_KEY(v, other, UNIT(s)->dependencies[UNIT_TRIGGERS], i) + if (unit_active_or_pending(other)) { + pending = true; + break; + } + + if (!pending) { + if (!UNIT_ISSET(s->service)) { + log_unit_error(UNIT(s), "Service to activate vanished, refusing activation."); + r = -ENOENT; + goto fail; + } + + r = manager_add_job(UNIT(s)->manager, JOB_START, UNIT_DEREF(s->service), JOB_REPLACE, &error, NULL); + if (r < 0) + goto fail; + } + + socket_set_state(s, SOCKET_RUNNING); + } else { + _cleanup_free_ char *prefix = NULL, *instance = NULL, *name = NULL; + _cleanup_(socket_peer_unrefp) SocketPeer *p = NULL; + Service *service; + + if (s->n_connections >= s->max_connections) { + log_unit_warning(UNIT(s), "Too many incoming connections (%u), dropping connection.", + s->n_connections); + goto refuse; + } + + if (s->max_connections_per_source > 0) { + r = socket_acquire_peer(s, cfd, &p); + if (r < 0) { + goto refuse; + } else if (r > 0 && p->n_ref > s->max_connections_per_source) { + _cleanup_free_ char *t = NULL; + + (void) sockaddr_pretty(&p->peer.sa, p->peer_salen, true, false, &t); + + log_unit_warning(UNIT(s), + "Too many incoming connections (%u) from source %s, dropping connection.", + p->n_ref, strnull(t)); + goto refuse; + } + } + + r = socket_instantiate_service(s); + if (r < 0) + goto fail; + + r = instance_from_socket(cfd, s->n_accepted, &instance); + if (r < 0) { + if (r != -ENOTCONN) + goto fail; + + /* ENOTCONN is legitimate if TCP RST was received. + * This connection is over, but the socket unit lives on. */ + log_unit_debug(UNIT(s), "Got ENOTCONN on incoming socket, assuming aborted connection attempt, ignoring."); + goto refuse; + } + + r = unit_name_to_prefix(UNIT(s)->id, &prefix); + if (r < 0) + goto fail; + + r = unit_name_build(prefix, instance, ".service", &name); + if (r < 0) + goto fail; + + r = unit_add_name(UNIT_DEREF(s->service), name); + if (r < 0) + goto fail; + + service = SERVICE(UNIT_DEREF(s->service)); + unit_ref_unset(&s->service); + + s->n_accepted++; + unit_choose_id(UNIT(service), name); + + r = service_set_socket_fd(service, cfd, s, s->selinux_context_from_net); + if (r < 0) + goto fail; + + cfd = -1; /* We passed ownership of the fd to the service now. Forget it here. */ + s->n_connections++; + + service->peer = TAKE_PTR(p); /* Pass ownership of the peer reference */ + + r = manager_add_job(UNIT(s)->manager, JOB_START, UNIT(service), JOB_REPLACE, &error, NULL); + if (r < 0) { + /* We failed to activate the new service, but it still exists. Let's make sure the service + * closes and forgets the connection fd again, immediately. */ + service_close_socket_fd(service); + goto fail; + } + + /* Notify clients about changed counters */ + unit_add_to_dbus_queue(UNIT(s)); + } + + return; + +refuse: + s->n_refused++; + safe_close(cfd); + return; + +fail: + log_unit_warning(UNIT(s), "Failed to queue service startup job (Maybe the service file is missing or not a %s unit?): %s", + cfd >= 0 ? "template" : "non-template", + bus_error_message(&error, r)); + + socket_enter_stop_pre(s, SOCKET_FAILURE_RESOURCES); + safe_close(cfd); +} + +static void socket_run_next(Socket *s) { + int r; + + assert(s); + assert(s->control_command); + assert(s->control_command->command_next); + + socket_unwatch_control_pid(s); + + s->control_command = s->control_command->command_next; + + r = socket_spawn(s, s->control_command, &s->control_pid); + if (r < 0) + goto fail; + + return; + +fail: + log_unit_warning_errno(UNIT(s), r, "Failed to run next task: %m"); + + if (s->state == SOCKET_START_POST) + socket_enter_stop_pre(s, SOCKET_FAILURE_RESOURCES); + else if (s->state == SOCKET_STOP_POST) + socket_enter_dead(s, SOCKET_FAILURE_RESOURCES); + else + socket_enter_signal(s, SOCKET_FINAL_SIGTERM, SOCKET_FAILURE_RESOURCES); +} + +static int socket_start(Unit *u) { + Socket *s = SOCKET(u); + int r; + + assert(s); + + /* We cannot fulfill this request right now, try again later + * please! */ + if (IN_SET(s->state, + SOCKET_STOP_PRE, + SOCKET_STOP_PRE_SIGKILL, + SOCKET_STOP_PRE_SIGTERM, + SOCKET_STOP_POST, + SOCKET_FINAL_SIGTERM, + SOCKET_FINAL_SIGKILL)) + return -EAGAIN; + + /* Already on it! */ + if (IN_SET(s->state, + SOCKET_START_PRE, + SOCKET_START_CHOWN, + SOCKET_START_POST)) + return 0; + + /* Cannot run this without the service being around */ + if (UNIT_ISSET(s->service)) { + Service *service; + + service = SERVICE(UNIT_DEREF(s->service)); + + if (UNIT(service)->load_state != UNIT_LOADED) { + log_unit_error(u, "Socket service %s not loaded, refusing.", UNIT(service)->id); + return -ENOENT; + } + + /* If the service is already active we cannot start the + * socket */ + if (!IN_SET(service->state, SERVICE_DEAD, SERVICE_FAILED, SERVICE_AUTO_RESTART)) { + log_unit_error(u, "Socket service %s already active, refusing.", UNIT(service)->id); + return -EBUSY; + } + } + + assert(IN_SET(s->state, SOCKET_DEAD, SOCKET_FAILED)); + + r = unit_start_limit_test(u); + if (r < 0) { + socket_enter_dead(s, SOCKET_FAILURE_START_LIMIT_HIT); + return r; + } + + r = unit_acquire_invocation_id(u); + if (r < 0) + return r; + + s->result = SOCKET_SUCCESS; + exec_command_reset_status_list_array(s->exec_command, _SOCKET_EXEC_COMMAND_MAX); + + u->reset_accounting = true; + + socket_enter_start_pre(s); + return 1; +} + +static int socket_stop(Unit *u) { + Socket *s = SOCKET(u); + + assert(s); + + /* Already on it */ + if (IN_SET(s->state, + SOCKET_STOP_PRE, + SOCKET_STOP_PRE_SIGTERM, + SOCKET_STOP_PRE_SIGKILL, + SOCKET_STOP_POST, + SOCKET_FINAL_SIGTERM, + SOCKET_FINAL_SIGKILL)) + return 0; + + /* If there's already something running we go directly into + * kill mode. */ + if (IN_SET(s->state, + SOCKET_START_PRE, + SOCKET_START_CHOWN, + SOCKET_START_POST)) { + socket_enter_signal(s, SOCKET_STOP_PRE_SIGTERM, SOCKET_SUCCESS); + return -EAGAIN; + } + + assert(IN_SET(s->state, SOCKET_LISTENING, SOCKET_RUNNING)); + + socket_enter_stop_pre(s, SOCKET_SUCCESS); + return 1; +} + +static int socket_serialize(Unit *u, FILE *f, FDSet *fds) { + Socket *s = SOCKET(u); + SocketPort *p; + int r; + + assert(u); + assert(f); + assert(fds); + + (void) serialize_item(f, "state", socket_state_to_string(s->state)); + (void) serialize_item(f, "result", socket_result_to_string(s->result)); + (void) serialize_item_format(f, "n-accepted", "%u", s->n_accepted); + (void) serialize_item_format(f, "n-refused", "%u", s->n_refused); + + if (s->control_pid > 0) + (void) serialize_item_format(f, "control-pid", PID_FMT, s->control_pid); + + if (s->control_command_id >= 0) + (void) serialize_item(f, "control-command", socket_exec_command_to_string(s->control_command_id)); + + LIST_FOREACH(port, p, s->ports) { + int copy; + + if (p->fd < 0) + continue; + + copy = fdset_put_dup(fds, p->fd); + if (copy < 0) + return log_unit_warning_errno(u, copy, "Failed to serialize socket fd: %m"); + + if (p->type == SOCKET_SOCKET) { + _cleanup_free_ char *t = NULL; + + r = socket_address_print(&p->address, &t); + if (r < 0) + return log_unit_error_errno(u, r, "Failed to format socket address: %m"); + + if (socket_address_family(&p->address) == AF_NETLINK) + (void) serialize_item_format(f, "netlink", "%i %s", copy, t); + else + (void) serialize_item_format(f, "socket", "%i %i %s", copy, p->address.type, t); + } else if (p->type == SOCKET_SPECIAL) + (void) serialize_item_format(f, "special", "%i %s", copy, p->path); + else if (p->type == SOCKET_MQUEUE) + (void) serialize_item_format(f, "mqueue", "%i %s", copy, p->path); + else if (p->type == SOCKET_USB_FUNCTION) + (void) serialize_item_format(f, "ffs", "%i %s", copy, p->path); + else { + assert(p->type == SOCKET_FIFO); + (void) serialize_item_format(f, "fifo", "%i %s", copy, p->path); + } + } + + return 0; +} + +static void socket_port_take_fd(SocketPort *p, FDSet *fds, int fd) { + assert(p); + + safe_close(p->fd); + p->fd = fdset_remove(fds, fd); +} + +static int socket_deserialize_item(Unit *u, const char *key, const char *value, FDSet *fds) { + Socket *s = SOCKET(u); + + assert(u); + assert(key); + assert(value); + + if (streq(key, "state")) { + SocketState state; + + state = socket_state_from_string(value); + if (state < 0) + log_unit_debug(u, "Failed to parse state value: %s", value); + else + s->deserialized_state = state; + } else if (streq(key, "result")) { + SocketResult f; + + f = socket_result_from_string(value); + if (f < 0) + log_unit_debug(u, "Failed to parse result value: %s", value); + else if (f != SOCKET_SUCCESS) + s->result = f; + + } else if (streq(key, "n-accepted")) { + unsigned k; + + if (safe_atou(value, &k) < 0) + log_unit_debug(u, "Failed to parse n-accepted value: %s", value); + else + s->n_accepted += k; + } else if (streq(key, "n-refused")) { + unsigned k; + + if (safe_atou(value, &k) < 0) + log_unit_debug(u, "Failed to parse n-refused value: %s", value); + else + s->n_refused += k; + } else if (streq(key, "control-pid")) { + pid_t pid; + + if (parse_pid(value, &pid) < 0) + log_unit_debug(u, "Failed to parse control-pid value: %s", value); + else + s->control_pid = pid; + } else if (streq(key, "control-command")) { + SocketExecCommand id; + + id = socket_exec_command_from_string(value); + if (id < 0) + log_unit_debug(u, "Failed to parse exec-command value: %s", value); + else { + s->control_command_id = id; + s->control_command = s->exec_command[id]; + } + } else if (streq(key, "fifo")) { + int fd, skip = 0; + SocketPort *p; + + if (sscanf(value, "%i %n", &fd, &skip) < 1 || fd < 0 || !fdset_contains(fds, fd)) + log_unit_debug(u, "Failed to parse fifo value: %s", value); + else + LIST_FOREACH(port, p, s->ports) + if (p->type == SOCKET_FIFO && + path_equal_or_files_same(p->path, value+skip, 0)) { + socket_port_take_fd(p, fds, fd); + break; + } + + } else if (streq(key, "special")) { + int fd, skip = 0; + SocketPort *p; + + if (sscanf(value, "%i %n", &fd, &skip) < 1 || fd < 0 || !fdset_contains(fds, fd)) + log_unit_debug(u, "Failed to parse special value: %s", value); + else + LIST_FOREACH(port, p, s->ports) + if (p->type == SOCKET_SPECIAL && + path_equal_or_files_same(p->path, value+skip, 0)) { + socket_port_take_fd(p, fds, fd); + break; + } + + } else if (streq(key, "mqueue")) { + int fd, skip = 0; + SocketPort *p; + + if (sscanf(value, "%i %n", &fd, &skip) < 1 || fd < 0 || !fdset_contains(fds, fd)) + log_unit_debug(u, "Failed to parse mqueue value: %s", value); + else + LIST_FOREACH(port, p, s->ports) + if (p->type == SOCKET_MQUEUE && + streq(p->path, value+skip)) { + socket_port_take_fd(p, fds, fd); + break; + } + + } else if (streq(key, "socket")) { + int fd, type, skip = 0; + SocketPort *p; + + if (sscanf(value, "%i %i %n", &fd, &type, &skip) < 2 || fd < 0 || type < 0 || !fdset_contains(fds, fd)) + log_unit_debug(u, "Failed to parse socket value: %s", value); + else + LIST_FOREACH(port, p, s->ports) + if (socket_address_is(&p->address, value+skip, type)) { + socket_port_take_fd(p, fds, fd); + break; + } + + } else if (streq(key, "netlink")) { + int fd, skip = 0; + SocketPort *p; + + if (sscanf(value, "%i %n", &fd, &skip) < 1 || fd < 0 || !fdset_contains(fds, fd)) + log_unit_debug(u, "Failed to parse socket value: %s", value); + else + LIST_FOREACH(port, p, s->ports) + if (socket_address_is_netlink(&p->address, value+skip)) { + socket_port_take_fd(p, fds, fd); + break; + } + + } else if (streq(key, "ffs")) { + int fd, skip = 0; + SocketPort *p; + + if (sscanf(value, "%i %n", &fd, &skip) < 1 || fd < 0 || !fdset_contains(fds, fd)) + log_unit_debug(u, "Failed to parse ffs value: %s", value); + else + LIST_FOREACH(port, p, s->ports) + if (p->type == SOCKET_USB_FUNCTION && + path_equal_or_files_same(p->path, value+skip, 0)) { + socket_port_take_fd(p, fds, fd); + break; + } + + } else + log_unit_debug(UNIT(s), "Unknown serialization key: %s", key); + + return 0; +} + +static void socket_distribute_fds(Unit *u, FDSet *fds) { + Socket *s = SOCKET(u); + SocketPort *p; + + assert(u); + + LIST_FOREACH(port, p, s->ports) { + Iterator i; + int fd; + + if (p->type != SOCKET_SOCKET) + continue; + + if (p->fd >= 0) + continue; + + FDSET_FOREACH(fd, fds, i) { + if (socket_address_matches_fd(&p->address, fd)) { + p->fd = fdset_remove(fds, fd); + s->deserialized_state = SOCKET_LISTENING; + break; + } + } + } +} + +_pure_ static UnitActiveState socket_active_state(Unit *u) { + assert(u); + + return state_translation_table[SOCKET(u)->state]; +} + +_pure_ static const char *socket_sub_state_to_string(Unit *u) { + assert(u); + + return socket_state_to_string(SOCKET(u)->state); +} + +const char* socket_port_type_to_string(SocketPort *p) { + + assert(p); + + switch (p->type) { + + case SOCKET_SOCKET: + + switch (p->address.type) { + + case SOCK_STREAM: + return "Stream"; + + case SOCK_DGRAM: + return "Datagram"; + + case SOCK_SEQPACKET: + return "SequentialPacket"; + + case SOCK_RAW: + if (socket_address_family(&p->address) == AF_NETLINK) + return "Netlink"; + + _fallthrough_; + default: + return NULL; + } + + case SOCKET_SPECIAL: + return "Special"; + + case SOCKET_MQUEUE: + return "MessageQueue"; + + case SOCKET_FIFO: + return "FIFO"; + + case SOCKET_USB_FUNCTION: + return "USBFunction"; + + default: + return NULL; + } +} + +SocketType socket_port_type_from_string(const char *s) { + assert(s); + + if (STR_IN_SET(s, "Stream", "Datagram", "SequentialPacket", "Netlink")) + return SOCKET_SOCKET; + else if (streq(s, "Special")) + return SOCKET_SPECIAL; + else if (streq(s, "MessageQueue")) + return SOCKET_MQUEUE; + else if (streq(s, "FIFO")) + return SOCKET_FIFO; + else if (streq(s, "USBFunction")) + return SOCKET_USB_FUNCTION; + else + return _SOCKET_TYPE_INVALID; +} + +_pure_ static bool socket_may_gc(Unit *u) { + Socket *s = SOCKET(u); + + assert(u); + + return s->n_connections == 0; +} + +static int socket_accept_do(Socket *s, int fd) { + int cfd; + + assert(s); + assert(fd >= 0); + + for (;;) { + cfd = accept4(fd, NULL, NULL, SOCK_NONBLOCK); + if (cfd < 0) { + if (errno == EINTR) + continue; + + return -errno; + } + + break; + } + + return cfd; +} + +static int socket_accept_in_cgroup(Socket *s, SocketPort *p, int fd) { + _cleanup_close_pair_ int pair[2] = { -1, -1 }; + int cfd, r; + pid_t pid; + + assert(s); + assert(p); + assert(fd >= 0); + + /* Similar to socket_address_listen_in_cgroup(), but for accept() rathern than socket(): make sure that any + * connection socket is also properly associated with the cgroup. */ + + if (!IN_SET(p->address.sockaddr.sa.sa_family, AF_INET, AF_INET6)) + goto shortcut; + + r = bpf_firewall_supported(); + if (r < 0) + return r; + if (r == BPF_FIREWALL_UNSUPPORTED) + goto shortcut; + + if (socketpair(AF_UNIX, SOCK_SEQPACKET|SOCK_CLOEXEC, 0, pair) < 0) + return log_unit_error_errno(UNIT(s), errno, "Failed to create communication channel: %m"); + + r = unit_fork_helper_process(UNIT(s), "(sd-accept)", &pid); + if (r < 0) + return log_unit_error_errno(UNIT(s), r, "Failed to fork off accept stub process: %m"); + if (r == 0) { + /* Child */ + + pair[0] = safe_close(pair[0]); + + cfd = socket_accept_do(s, fd); + if (cfd < 0) { + log_unit_error_errno(UNIT(s), cfd, "Failed to accept connection socket: %m"); + _exit(EXIT_FAILURE); + } + + r = send_one_fd(pair[1], cfd, 0); + if (r < 0) { + log_unit_error_errno(UNIT(s), r, "Failed to send connection socket to parent: %m"); + _exit(EXIT_FAILURE); + } + + _exit(EXIT_SUCCESS); + } + + pair[1] = safe_close(pair[1]); + cfd = receive_one_fd(pair[0], 0); + + /* We synchronously wait for the helper, as it shouldn't be slow */ + r = wait_for_terminate_and_check("(sd-accept)", pid, WAIT_LOG_ABNORMAL); + if (r < 0) { + safe_close(cfd); + return r; + } + + if (cfd < 0) + return log_unit_error_errno(UNIT(s), cfd, "Failed to receive connection socket: %m"); + + return cfd; + +shortcut: + cfd = socket_accept_do(s, fd); + if (cfd < 0) + return log_unit_error_errno(UNIT(s), cfd, "Failed to accept connection socket: %m"); + + return cfd; +} + +static int socket_dispatch_io(sd_event_source *source, int fd, uint32_t revents, void *userdata) { + SocketPort *p = userdata; + int cfd = -1; + + assert(p); + assert(fd >= 0); + + if (p->socket->state != SOCKET_LISTENING) + return 0; + + log_unit_debug(UNIT(p->socket), "Incoming traffic"); + + if (revents != EPOLLIN) { + + if (revents & EPOLLHUP) + log_unit_error(UNIT(p->socket), "Got POLLHUP on a listening socket. The service probably invoked shutdown() on it, and should better not do that."); + else + log_unit_error(UNIT(p->socket), "Got unexpected poll event (0x%x) on socket.", revents); + goto fail; + } + + if (p->socket->accept && + p->type == SOCKET_SOCKET && + socket_address_can_accept(&p->address)) { + + cfd = socket_accept_in_cgroup(p->socket, p, fd); + if (cfd < 0) + goto fail; + + socket_apply_socket_options(p->socket, cfd); + } + + socket_enter_running(p->socket, cfd); + return 0; + +fail: + socket_enter_stop_pre(p->socket, SOCKET_FAILURE_RESOURCES); + return 0; +} + +static void socket_sigchld_event(Unit *u, pid_t pid, int code, int status) { + Socket *s = SOCKET(u); + SocketResult f; + + assert(s); + assert(pid >= 0); + + if (pid != s->control_pid) + return; + + s->control_pid = 0; + + if (is_clean_exit(code, status, EXIT_CLEAN_COMMAND, NULL)) + f = SOCKET_SUCCESS; + else if (code == CLD_EXITED) + f = SOCKET_FAILURE_EXIT_CODE; + else if (code == CLD_KILLED) + f = SOCKET_FAILURE_SIGNAL; + else if (code == CLD_DUMPED) + f = SOCKET_FAILURE_CORE_DUMP; + else + assert_not_reached("Unknown sigchld code"); + + if (s->control_command) { + exec_status_exit(&s->control_command->exec_status, &s->exec_context, pid, code, status); + + if (s->control_command->flags & EXEC_COMMAND_IGNORE_FAILURE) + f = SOCKET_SUCCESS; + } + + unit_log_process_exit( + u, f == SOCKET_SUCCESS ? LOG_DEBUG : LOG_NOTICE, + "Control process", + socket_exec_command_to_string(s->control_command_id), + code, status); + + if (s->result == SOCKET_SUCCESS) + s->result = f; + + if (s->control_command && + s->control_command->command_next && + f == SOCKET_SUCCESS) { + + log_unit_debug(u, "Running next command for state %s", socket_state_to_string(s->state)); + socket_run_next(s); + } else { + s->control_command = NULL; + s->control_command_id = _SOCKET_EXEC_COMMAND_INVALID; + + /* No further commands for this step, so let's figure + * out what to do next */ + + log_unit_debug(u, "Got final SIGCHLD for state %s", socket_state_to_string(s->state)); + + switch (s->state) { + + case SOCKET_START_PRE: + if (f == SOCKET_SUCCESS) + socket_enter_start_chown(s); + else + socket_enter_signal(s, SOCKET_FINAL_SIGTERM, f); + break; + + case SOCKET_START_CHOWN: + if (f == SOCKET_SUCCESS) + socket_enter_start_post(s); + else + socket_enter_stop_pre(s, f); + break; + + case SOCKET_START_POST: + if (f == SOCKET_SUCCESS) + socket_enter_listening(s); + else + socket_enter_stop_pre(s, f); + break; + + case SOCKET_STOP_PRE: + case SOCKET_STOP_PRE_SIGTERM: + case SOCKET_STOP_PRE_SIGKILL: + socket_enter_stop_post(s, f); + break; + + case SOCKET_STOP_POST: + case SOCKET_FINAL_SIGTERM: + case SOCKET_FINAL_SIGKILL: + socket_enter_dead(s, f); + break; + + default: + assert_not_reached("Uh, control process died at wrong time."); + } + } + + /* Notify clients about changed exit status */ + unit_add_to_dbus_queue(u); +} + +static int socket_dispatch_timer(sd_event_source *source, usec_t usec, void *userdata) { + Socket *s = SOCKET(userdata); + + assert(s); + assert(s->timer_event_source == source); + + switch (s->state) { + + case SOCKET_START_PRE: + log_unit_warning(UNIT(s), "Starting timed out. Terminating."); + socket_enter_signal(s, SOCKET_FINAL_SIGTERM, SOCKET_FAILURE_TIMEOUT); + break; + + case SOCKET_START_CHOWN: + case SOCKET_START_POST: + log_unit_warning(UNIT(s), "Starting timed out. Stopping."); + socket_enter_stop_pre(s, SOCKET_FAILURE_TIMEOUT); + break; + + case SOCKET_STOP_PRE: + log_unit_warning(UNIT(s), "Stopping timed out. Terminating."); + socket_enter_signal(s, SOCKET_STOP_PRE_SIGTERM, SOCKET_FAILURE_TIMEOUT); + break; + + case SOCKET_STOP_PRE_SIGTERM: + if (s->kill_context.send_sigkill) { + log_unit_warning(UNIT(s), "Stopping timed out. Killing."); + socket_enter_signal(s, SOCKET_STOP_PRE_SIGKILL, SOCKET_FAILURE_TIMEOUT); + } else { + log_unit_warning(UNIT(s), "Stopping timed out. Skipping SIGKILL. Ignoring."); + socket_enter_stop_post(s, SOCKET_FAILURE_TIMEOUT); + } + break; + + case SOCKET_STOP_PRE_SIGKILL: + log_unit_warning(UNIT(s), "Processes still around after SIGKILL. Ignoring."); + socket_enter_stop_post(s, SOCKET_FAILURE_TIMEOUT); + break; + + case SOCKET_STOP_POST: + log_unit_warning(UNIT(s), "Stopping timed out (2). Terminating."); + socket_enter_signal(s, SOCKET_FINAL_SIGTERM, SOCKET_FAILURE_TIMEOUT); + break; + + case SOCKET_FINAL_SIGTERM: + if (s->kill_context.send_sigkill) { + log_unit_warning(UNIT(s), "Stopping timed out (2). Killing."); + socket_enter_signal(s, SOCKET_FINAL_SIGKILL, SOCKET_FAILURE_TIMEOUT); + } else { + log_unit_warning(UNIT(s), "Stopping timed out (2). Skipping SIGKILL. Ignoring."); + socket_enter_dead(s, SOCKET_FAILURE_TIMEOUT); + } + break; + + case SOCKET_FINAL_SIGKILL: + log_unit_warning(UNIT(s), "Still around after SIGKILL (2). Entering failed mode."); + socket_enter_dead(s, SOCKET_FAILURE_TIMEOUT); + break; + + default: + assert_not_reached("Timeout at wrong time."); + } + + return 0; +} + +int socket_collect_fds(Socket *s, int **fds) { + size_t k = 0, n = 0; + SocketPort *p; + int *rfds; + + assert(s); + assert(fds); + + /* Called from the service code for requesting our fds */ + + LIST_FOREACH(port, p, s->ports) { + if (p->fd >= 0) + n++; + n += p->n_auxiliary_fds; + } + + if (n <= 0) { + *fds = NULL; + return 0; + } + + rfds = new(int, n); + if (!rfds) + return -ENOMEM; + + LIST_FOREACH(port, p, s->ports) { + size_t i; + + if (p->fd >= 0) + rfds[k++] = p->fd; + for (i = 0; i < p->n_auxiliary_fds; ++i) + rfds[k++] = p->auxiliary_fds[i]; + } + + assert(k == n); + + *fds = rfds; + return (int) n; +} + +static void socket_reset_failed(Unit *u) { + Socket *s = SOCKET(u); + + assert(s); + + if (s->state == SOCKET_FAILED) + socket_set_state(s, SOCKET_DEAD); + + s->result = SOCKET_SUCCESS; +} + +void socket_connection_unref(Socket *s) { + assert(s); + + /* The service is dead. Yay! + * + * This is strictly for one-instance-per-connection + * services. */ + + assert(s->n_connections > 0); + s->n_connections--; + + log_unit_debug(UNIT(s), "One connection closed, %u left.", s->n_connections); +} + +static void socket_trigger_notify(Unit *u, Unit *other) { + Socket *s = SOCKET(u); + + assert(u); + assert(other); + + /* Filter out invocations with bogus state */ + if (other->load_state != UNIT_LOADED || other->type != UNIT_SERVICE) + return; + + /* Don't propagate state changes from the service if we are already down */ + if (!IN_SET(s->state, SOCKET_RUNNING, SOCKET_LISTENING)) + return; + + /* We don't care for the service state if we are in Accept=yes mode */ + if (s->accept) + return; + + /* Propagate start limit hit state */ + if (other->start_limit_hit) { + socket_enter_stop_pre(s, SOCKET_FAILURE_SERVICE_START_LIMIT_HIT); + return; + } + + /* Don't propagate anything if there's still a job queued */ + if (other->job) + return; + + if (IN_SET(SERVICE(other)->state, + SERVICE_DEAD, SERVICE_FAILED, + SERVICE_FINAL_SIGTERM, SERVICE_FINAL_SIGKILL, + SERVICE_AUTO_RESTART)) + socket_enter_listening(s); + + if (SERVICE(other)->state == SERVICE_RUNNING) + socket_set_state(s, SOCKET_RUNNING); +} + +static int socket_kill(Unit *u, KillWho who, int signo, sd_bus_error *error) { + return unit_kill_common(u, who, signo, -1, SOCKET(u)->control_pid, error); +} + +static int socket_get_timeout(Unit *u, usec_t *timeout) { + Socket *s = SOCKET(u); + usec_t t; + int r; + + if (!s->timer_event_source) + return 0; + + r = sd_event_source_get_time(s->timer_event_source, &t); + if (r < 0) + return r; + if (t == USEC_INFINITY) + return 0; + + *timeout = t; + return 1; +} + +char *socket_fdname(Socket *s) { + assert(s); + + /* Returns the name to use for $LISTEN_NAMES. If the user + * didn't specify anything specifically, use the socket unit's + * name as fallback. */ + + return s->fdname ?: UNIT(s)->id; +} + +static int socket_control_pid(Unit *u) { + Socket *s = SOCKET(u); + + assert(s); + + return s->control_pid; +} + +static const char* const socket_exec_command_table[_SOCKET_EXEC_COMMAND_MAX] = { + [SOCKET_EXEC_START_PRE] = "ExecStartPre", + [SOCKET_EXEC_START_CHOWN] = "ExecStartChown", + [SOCKET_EXEC_START_POST] = "ExecStartPost", + [SOCKET_EXEC_STOP_PRE] = "ExecStopPre", + [SOCKET_EXEC_STOP_POST] = "ExecStopPost" +}; + +DEFINE_STRING_TABLE_LOOKUP(socket_exec_command, SocketExecCommand); + +static const char* const socket_result_table[_SOCKET_RESULT_MAX] = { + [SOCKET_SUCCESS] = "success", + [SOCKET_FAILURE_RESOURCES] = "resources", + [SOCKET_FAILURE_TIMEOUT] = "timeout", + [SOCKET_FAILURE_EXIT_CODE] = "exit-code", + [SOCKET_FAILURE_SIGNAL] = "signal", + [SOCKET_FAILURE_CORE_DUMP] = "core-dump", + [SOCKET_FAILURE_START_LIMIT_HIT] = "start-limit-hit", + [SOCKET_FAILURE_TRIGGER_LIMIT_HIT] = "trigger-limit-hit", + [SOCKET_FAILURE_SERVICE_START_LIMIT_HIT] = "service-start-limit-hit" +}; + +DEFINE_STRING_TABLE_LOOKUP(socket_result, SocketResult); + +const UnitVTable socket_vtable = { + .object_size = sizeof(Socket), + .exec_context_offset = offsetof(Socket, exec_context), + .cgroup_context_offset = offsetof(Socket, cgroup_context), + .kill_context_offset = offsetof(Socket, kill_context), + .exec_runtime_offset = offsetof(Socket, exec_runtime), + .dynamic_creds_offset = offsetof(Socket, dynamic_creds), + + .sections = + "Unit\0" + "Socket\0" + "Install\0", + .private_section = "Socket", + + .can_transient = true, + + .init = socket_init, + .done = socket_done, + .load = socket_load, + + .coldplug = socket_coldplug, + + .dump = socket_dump, + + .start = socket_start, + .stop = socket_stop, + + .kill = socket_kill, + + .get_timeout = socket_get_timeout, + + .serialize = socket_serialize, + .deserialize_item = socket_deserialize_item, + .distribute_fds = socket_distribute_fds, + + .active_state = socket_active_state, + .sub_state_to_string = socket_sub_state_to_string, + + .may_gc = socket_may_gc, + + .sigchld_event = socket_sigchld_event, + + .trigger_notify = socket_trigger_notify, + + .reset_failed = socket_reset_failed, + + .control_pid = socket_control_pid, + + .bus_vtable = bus_socket_vtable, + .bus_set_property = bus_socket_set_property, + .bus_commit_properties = bus_socket_commit_properties, + + .status_message_formats = { + /*.starting_stopping = { + [0] = "Starting socket %s...", + [1] = "Stopping socket %s...", + },*/ + .finished_start_job = { + [JOB_DONE] = "Listening on %s.", + [JOB_FAILED] = "Failed to listen on %s.", + [JOB_TIMEOUT] = "Timed out starting %s.", + }, + .finished_stop_job = { + [JOB_DONE] = "Closed %s.", + [JOB_FAILED] = "Failed stopping %s.", + [JOB_TIMEOUT] = "Timed out stopping %s.", + }, + }, +}; |