Adding upstream version 255.4.upstream/255.4

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

2 files changed, 364 insertions, 0 deletions

diff --git a/src/initctl/initctl.c b/src/initctl/initctl.c
new file mode 100644
index 0000000..d1b7c30
--- /dev/null
+++ b/src/initctl/initctl.c
@@ -0,0 +1,355 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include <ctype.h>
+#include <errno.h>
+#include <stdio.h>
+#include <sys/epoll.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include "sd-bus.h"
+#include "sd-daemon.h"
+
+#include "alloc-util.h"
+#include "bus-error.h"
+#include "bus-locator.h"
+#include "bus-util.h"
+#include "constants.h"
+#include "daemon-util.h"
+#include "fd-util.h"
+#include "format-util.h"
+#include "initreq.h"
+#include "list.h"
+#include "log.h"
+#include "main-func.h"
+#include "memory-util.h"
+#include "process-util.h"
+#include "reboot-util.h"
+#include "special.h"
+
+#define SERVER_FD_MAX 16
+#define TIMEOUT_MSEC ((int) (DEFAULT_EXIT_USEC/USEC_PER_MSEC))
+
+typedef struct Fifo Fifo;
+
+typedef struct Server {
+        int epoll_fd;
+
+        LIST_HEAD(Fifo, fifos);
+        unsigned n_fifos;
+
+        sd_bus *bus;
+
+        bool quit;
+} Server;
+
+struct Fifo {
+        Server *server;
+
+        int fd;
+
+        struct init_request buffer;
+        size_t bytes_read;
+
+        LIST_FIELDS(Fifo, fifo);
+};
+
+static const char *translate_runlevel(int runlevel, bool *isolate) {
+        static const struct {
+                const int runlevel;
+                const char *special;
+                bool isolate;
+        } table[] = {
+                { '0', SPECIAL_POWEROFF_TARGET,   false },
+                { '1', SPECIAL_RESCUE_TARGET,     true  },
+                { 's', SPECIAL_RESCUE_TARGET,     true  },
+                { 'S', SPECIAL_RESCUE_TARGET,     true  },
+                { '2', SPECIAL_MULTI_USER_TARGET, true  },
+                { '3', SPECIAL_MULTI_USER_TARGET, true  },
+                { '4', SPECIAL_MULTI_USER_TARGET, true  },
+                { '5', SPECIAL_GRAPHICAL_TARGET,  true  },
+                { '6', SPECIAL_REBOOT_TARGET,     false },
+        };
+
+        assert(isolate);
+
+        for (size_t i = 0; i < ELEMENTSOF(table); i++)
+                if (table[i].runlevel == runlevel) {
+                        *isolate = table[i].isolate;
+                        if (runlevel == '6' && kexec_loaded())
+                                return SPECIAL_KEXEC_TARGET;
+                        return table[i].special;
+                }
+
+        return NULL;
+}
+
+static int change_runlevel(Server *s, int runlevel) {
+        const char *target;
+        _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
+        const char *mode;
+        bool isolate = false;
+        int r;
+
+        assert(s);
+
+        target = translate_runlevel(runlevel, &isolate);
+        if (!target) {
+                log_warning("Got request for unknown runlevel %c, ignoring.", runlevel);
+                return 0;
+        }
+
+        if (isolate)
+                mode = "isolate";
+        else
+                mode = "replace-irreversibly";
+
+        log_debug("Requesting %s/start/%s", target, mode);
+
+        r = bus_call_method(s->bus, bus_systemd_mgr, "StartUnit", &error, NULL, "ss", target, mode);
+        if (r < 0)
+                return log_error_errno(r, "Failed to change runlevel: %s", bus_error_message(&error, r));
+
+        return 0;
+}
+
+static void request_process(Server *s, const struct init_request *req) {
+        assert(s);
+        assert(req);
+
+        if (req->magic != INIT_MAGIC) {
+                log_error("Got initctl request with invalid magic. Ignoring.");
+                return;
+        }
+
+        switch (req->cmd) {
+
+        case INIT_CMD_RUNLVL:
+                if (!isprint(req->runlevel))
+                        log_error("Got invalid runlevel. Ignoring.");
+                else
+                        switch (req->runlevel) {
+
+                        /* we are async anyway, so just use kill for reexec/reload */
+                        case 'u':
+                        case 'U':
+                                if (kill(1, SIGTERM) < 0)
+                                        log_error_errno(errno, "kill() failed: %m");
+
+                                /* The bus connection will be
+                                 * terminated if PID 1 is reexecuted,
+                                 * hence let's just exit here, and
+                                 * rely on that we'll be restarted on
+                                 * the next request */
+                                s->quit = true;
+                                break;
+
+                        case 'q':
+                        case 'Q':
+                                if (kill(1, SIGHUP) < 0)
+                                        log_error_errno(errno, "kill() failed: %m");
+                                break;
+
+                        default:
+                                (void) change_runlevel(s, req->runlevel);
+                        }
+                return;
+
+        case INIT_CMD_POWERFAIL:
+        case INIT_CMD_POWERFAILNOW:
+        case INIT_CMD_POWEROK:
+                log_warning("Received UPS/power initctl request. This is not implemented in systemd. Upgrade your UPS daemon!");
+                return;
+
+        case INIT_CMD_CHANGECONS:
+                log_warning("Received console change initctl request. This is not implemented in systemd.");
+                return;
+
+        case INIT_CMD_SETENV:
+        case INIT_CMD_UNSETENV:
+                log_warning("Received environment initctl request. This is not implemented in systemd.");
+                return;
+
+        default:
+                log_warning("Received unknown initctl request. Ignoring.");
+                return;
+        }
+}
+
+static int fifo_process(Fifo *f) {
+        ssize_t l;
+
+        assert(f);
+
+        errno = EIO;
+        l = read(f->fd,
+                 ((uint8_t*) &f->buffer) + f->bytes_read,
+                 sizeof(f->buffer) - f->bytes_read);
+        if (l <= 0) {
+                if (errno == EAGAIN)
+                        return 0;
+
+                return log_warning_errno(errno, "Failed to read from fifo: %m");
+        }
+
+        f->bytes_read += l;
+        assert(f->bytes_read <= sizeof(f->buffer));
+
+        if (f->bytes_read == sizeof(f->buffer)) {
+                request_process(f->server, &f->buffer);
+                f->bytes_read = 0;
+        }
+
+        return 0;
+}
+
+static Fifo* fifo_free(Fifo *f) {
+        if (!f)
+                return NULL;
+
+        if (f->server) {
+                assert(f->server->n_fifos > 0);
+                f->server->n_fifos--;
+                LIST_REMOVE(fifo, f->server->fifos, f);
+        }
+
+        if (f->fd >= 0) {
+                if (f->server)
+                        (void) epoll_ctl(f->server->epoll_fd, EPOLL_CTL_DEL, f->fd, NULL);
+
+                safe_close(f->fd);
+        }
+
+        return mfree(f);
+}
+DEFINE_TRIVIAL_CLEANUP_FUNC(Fifo*, fifo_free);
+
+static void server_done(Server *s) {
+        assert(s);
+
+        while (s->fifos)
+                fifo_free(s->fifos);
+
+        s->epoll_fd = safe_close(s->epoll_fd);
+        s->bus = sd_bus_flush_close_unref(s->bus);
+}
+
+static int server_init(Server *s, unsigned n_sockets) {
+        int r;
+
+        /* This function will leave s partially initialized on failure. Caller needs to clean up. */
+
+        assert(s);
+        assert(n_sockets > 0);
+
+        s->epoll_fd = epoll_create1(EPOLL_CLOEXEC);
+        if (s->epoll_fd < 0)
+                return log_error_errno(errno, "Failed to create epoll object: %m");
+
+        for (unsigned i = 0; i < n_sockets; i++) {
+                _cleanup_(fifo_freep) Fifo *f = NULL;
+                int fd = SD_LISTEN_FDS_START + i;
+
+                r = sd_is_fifo(fd, NULL);
+                if (r < 0)
+                        return log_error_errno(r, "Failed to determine file descriptor type: %m");
+                if (!r)
+                        return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Wrong file descriptor type.");
+
+                f = new0(Fifo, 1);
+                if (!f)
+                        return log_oom();
+
+                struct epoll_event ev = {
+                        .events = EPOLLIN,
+                        .data.ptr = f,
+                };
+
+                if (epoll_ctl(s->epoll_fd, EPOLL_CTL_ADD, fd, &ev) < 0)
+                        return log_error_errno(errno, "Failed to add fifo fd to epoll object: %m");
+
+                f->fd = fd;
+                f->server = s;
+                LIST_PREPEND(fifo, s->fifos, TAKE_PTR(f));
+                s->n_fifos++;
+        }
+
+        r = bus_connect_system_systemd(&s->bus);
+        if (r < 0)
+                return log_error_errno(r, "Failed to get D-Bus connection: %m");
+
+        return 0;
+}
+
+static int process_event(Server *s, struct epoll_event *ev) {
+        int r;
+        _cleanup_(fifo_freep) Fifo *f = NULL;
+
+        assert(s);
+        assert(ev);
+
+        if (!(ev->events & EPOLLIN))
+                return log_info_errno(SYNTHETIC_ERRNO(EIO),
+                                      "Got invalid event from epoll. (3)");
+
+        f = (Fifo*) ev->data.ptr;
+        r = fifo_process(f);
+        if (r < 0)
+                return log_info_errno(r, "Got error on fifo: %m");
+
+        TAKE_PTR(f);
+
+        return 0;
+}
+
+static int run(int argc, char *argv[]) {
+        _cleanup_(server_done) Server server = { .epoll_fd = -EBADF };
+        _unused_ _cleanup_(notify_on_cleanup) const char *notify_stop = NULL;
+        int r, n;
+
+        if (argc > 1)
+                return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
+                                       "This program does not take arguments.");
+
+        log_setup();
+
+        umask(0022);
+
+        n = sd_listen_fds(true);
+        if (n < 0)
+                return log_error_errno(errno,
+                                       "Failed to read listening file descriptors from environment: %m");
+
+        if (n <= 0 || n > SERVER_FD_MAX)
+                return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
+                                       "No or too many file descriptors passed.");
+
+        r = server_init(&server, (unsigned) n);
+        if (r < 0)
+                return r;
+
+        notify_stop = notify_start(NOTIFY_READY, NOTIFY_STOPPING);
+
+        while (!server.quit) {
+                struct epoll_event event;
+                int k;
+
+                k = epoll_wait(server.epoll_fd, &event, 1, TIMEOUT_MSEC);
+                if (k < 0) {
+                        if (errno == EINTR)
+                                continue;
+                        return log_error_errno(errno, "epoll_wait() failed: %m");
+                }
+                if (k == 0)
+                        break;
+
+                r = process_event(&server, &event);
+                if (r < 0)
+                        return r;
+        }
+
+        return 0;
+}
+
+DEFINE_MAIN_FUNCTION(run);
diff --git a/src/initctl/meson.build b/src/initctl/meson.build
new file mode 100644
index 0000000..c9fddc9
--- /dev/null
+++ b/src/initctl/meson.build
@@ -0,0 +1,9 @@
+# SPDX-License-Identifier: LGPL-2.1-or-later
+
+executables += [
+        libexec_template + {
+                'name' : 'systemd-initctl',
+                'conditions' : ['HAVE_SYSV_COMPAT'],
+                'sources' : files('initctl.c'),
+        },
+]