From: Ivan Kruglov <mail@ikruglov.com>
Date: Tue, 22 Oct 2024 11:38:06 +0000 (+0200)
Subject: machine: introduce machine_start_getty() and machine_start_shell() helpers
X-Git-Tag: v257-rc1~12^2~4
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=41f1f283d7e75485602a0612d2436d83ecfb1a02;p=thirdparty%2Fsystemd.git

machine: introduce machine_start_getty() and machine_start_shell() helpers
---

diff --git a/src/machine/machine-dbus.c b/src/machine/machine-dbus.c
index de70c0a1881..371441a18e3 100644
--- a/src/machine/machine-dbus.c
+++ b/src/machine/machine-dbus.c
@@ -294,59 +294,11 @@ int bus_machine_method_open_pty(sd_bus_message *message, void *userdata, sd_bus_
         return sd_bus_send(NULL, reply, NULL);
 }
 
-static int container_bus_new(Machine *m, sd_bus_error *error, sd_bus **ret) {
-        int r;
-
-        assert(m);
-        assert(ret);
-
-        switch (m->class) {
-
-        case MACHINE_HOST:
-                *ret = NULL;
-                break;
-
-        case MACHINE_CONTAINER: {
-                _cleanup_(sd_bus_close_unrefp) sd_bus *bus = NULL;
-                char *address;
-
-                r = sd_bus_new(&bus);
-                if (r < 0)
-                        return r;
-
-                if (asprintf(&address, "x-machine-unix:pid=%" PID_PRI, m->leader.pid) < 0)
-                        return -ENOMEM;
-
-                bus->address = address;
-                bus->bus_client = true;
-                bus->trusted = false;
-                bus->runtime_scope = RUNTIME_SCOPE_SYSTEM;
-
-                r = sd_bus_start(bus);
-                if (r == -ENOENT)
-                        return sd_bus_error_set_errnof(error, r, "There is no system bus in container %s.", m->name);
-                if (r < 0)
-                        return r;
-
-                *ret = TAKE_PTR(bus);
-                break;
-        }
-
-        default:
-                return -EOPNOTSUPP;
-        }
-
-        return 0;
-}
-
 int bus_machine_method_open_login(sd_bus_message *message, void *userdata, sd_bus_error *error) {
         _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL;
         _cleanup_free_ char *pty_name = NULL;
-        _cleanup_(sd_bus_flush_close_unrefp) sd_bus *allocated_bus = NULL;
         _cleanup_close_ int master = -EBADF;
-        sd_bus *container_bus = NULL;
         Machine *m = ASSERT_PTR(userdata);
-        const char *p, *getty;
         int r;
 
         assert(message);
@@ -372,18 +324,7 @@ int bus_machine_method_open_login(sd_bus_message *message, void *userdata, sd_bu
         if (master < 0)
                 return master;
 
-        p = path_startswith(pty_name, "/dev/pts/");
-        assert(p);
-
-        r = container_bus_new(m, error, &allocated_bus);
-        if (r < 0)
-                return r;
-
-        container_bus = allocated_bus ?: m->manager->bus;
-
-        getty = strjoina("container-getty@", p, ".service");
-
-        r = bus_call_method(container_bus, bus_systemd_mgr, "StartUnit", error, NULL, "ss", getty, "replace");
+        r = machine_start_getty(m, pty_name, error);
         if (r < 0)
                 return r;
 
@@ -399,15 +340,13 @@ int bus_machine_method_open_login(sd_bus_message *message, void *userdata, sd_bu
 }
 
 int bus_machine_method_open_shell(sd_bus_message *message, void *userdata, sd_bus_error *error) {
-        _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL, *tm = NULL;
+        _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL;
         _cleanup_free_ char *pty_name = NULL;
-        _cleanup_(sd_bus_flush_close_unrefp) sd_bus *allocated_bus = NULL;
-        sd_bus *container_bus = NULL;
-        _cleanup_close_ int master = -EBADF, slave = -EBADF;
+        _cleanup_close_ int master = -EBADF;
         _cleanup_strv_free_ char **env = NULL, **args_wire = NULL, **args = NULL;
         _cleanup_free_ char *command_line = NULL;
         Machine *m = ASSERT_PTR(userdata);
-        const char *unit, *user, *path, *description, *utmp_id;
+        const char *user, *path;
         int r;
 
         assert(message);
@@ -484,153 +423,10 @@ int bus_machine_method_open_shell(sd_bus_message *message, void *userdata, sd_bu
         if (master < 0)
                 return master;
 
-        /* First try to get an fd for the PTY peer via the new racefree ioctl(), directly. Otherwise go via
-         * joining the namespace, because it goes by path */
-        slave = pty_open_peer_racefree(master, O_RDWR|O_NOCTTY|O_CLOEXEC);
-        if (ERRNO_IS_NEG_NOT_SUPPORTED(slave))
-                slave = machine_open_terminal(m, pty_name, O_RDWR|O_NOCTTY|O_CLOEXEC);
-        if (slave < 0)
-                return slave;
-
-        utmp_id = path_startswith(pty_name, "/dev/");
-        assert(utmp_id);
-
-        r = container_bus_new(m, error, &allocated_bus);
-        if (r < 0)
-                return r;
-
-        container_bus = allocated_bus ?: m->manager->bus;
-
-        r = bus_message_new_method_call(container_bus, &tm, bus_systemd_mgr, "StartTransientUnit");
-        if (r < 0)
-                return r;
-
-        /* Name and mode */
-        const char *p = ASSERT_PTR(path_startswith(pty_name, "/dev/pts/"));
-
-        unit = strjoina("container-shell@", p, ".service");
-        r = sd_bus_message_append(tm, "ss", unit, "fail");
-        if (r < 0)
-                return r;
-
-        /* Properties */
-        r = sd_bus_message_open_container(tm, 'a', "(sv)");
-        if (r < 0)
-                return r;
-
-        description = strjoina("Shell for User ", user);
-        r = sd_bus_message_append(tm,
-                                  "(sv)(sv)(sv)(sv)(sv)(sv)(sv)(sv)(sv)(sv)(sv)(sv)(sv)",
-                                  "Description", "s", description,
-                                  "StandardInputFileDescriptor", "h", slave,
-                                  "StandardOutputFileDescriptor", "h", slave,
-                                  "StandardErrorFileDescriptor", "h", slave,
-                                  "SendSIGHUP", "b", true,
-                                  "IgnoreSIGPIPE", "b", false,
-                                  "KillMode", "s", "mixed",
-                                  "TTYPath", "s", pty_name,
-                                  "TTYReset", "b", true,
-                                  "UtmpIdentifier", "s", utmp_id,
-                                  "UtmpMode", "s", "user",
-                                  "PAMName", "s", "login",
-                                  "WorkingDirectory", "s", "-~");
-        if (r < 0)
-                return r;
-
-        r = sd_bus_message_append(tm, "(sv)", "User", "s", user);
-        if (r < 0)
-                return r;
-
-        if (!strv_isempty(env)) {
-                r = sd_bus_message_open_container(tm, 'r', "sv");
-                if (r < 0)
-                        return r;
-
-                r = sd_bus_message_append(tm, "s", "Environment");
-                if (r < 0)
-                        return r;
-
-                r = sd_bus_message_open_container(tm, 'v', "as");
-                if (r < 0)
-                        return r;
-
-                r = sd_bus_message_append_strv(tm, env);
-                if (r < 0)
-                        return r;
-
-                r = sd_bus_message_close_container(tm);
-                if (r < 0)
-                        return r;
-
-                r = sd_bus_message_close_container(tm);
-                if (r < 0)
-                        return r;
-        }
-
-        /* Exec container */
-        r = sd_bus_message_open_container(tm, 'r', "sv");
-        if (r < 0)
-                return r;
-
-        r = sd_bus_message_append(tm, "s", "ExecStart");
-        if (r < 0)
-                return r;
-
-        r = sd_bus_message_open_container(tm, 'v', "a(sasb)");
-        if (r < 0)
-                return r;
-
-        r = sd_bus_message_open_container(tm, 'a', "(sasb)");
-        if (r < 0)
-                return r;
-
-        r = sd_bus_message_open_container(tm, 'r', "sasb");
-        if (r < 0)
-                return r;
-
-        r = sd_bus_message_append(tm, "s", path);
-        if (r < 0)
-                return r;
-
-        r = sd_bus_message_append_strv(tm, args);
-        if (r < 0)
-                return r;
-
-        r = sd_bus_message_append(tm, "b", true);
-        if (r < 0)
-                return r;
-
-        r = sd_bus_message_close_container(tm);
-        if (r < 0)
-                return r;
-
-        r = sd_bus_message_close_container(tm);
-        if (r < 0)
-                return r;
-
-        r = sd_bus_message_close_container(tm);
-        if (r < 0)
-                return r;
-
-        r = sd_bus_message_close_container(tm);
-        if (r < 0)
-                return r;
-
-        r = sd_bus_message_close_container(tm);
+        r = machine_start_shell(m, master, pty_name, user, path, args, env, error);
         if (r < 0)
                 return r;
 
-        /* Auxiliary units */
-        r = sd_bus_message_append(tm, "a(sa(sv))", 0);
-        if (r < 0)
-                return r;
-
-        r = sd_bus_call(container_bus, tm, 0, error, NULL);
-        if (r < 0)
-                return r;
-
-        slave = safe_close(slave);
-
         r = sd_bus_message_new_method_return(message, &reply);
         if (r < 0)
                 return r;
diff --git a/src/machine/machine.c b/src/machine/machine.c
index 4da206cd5e8..b1ef7e034b9 100644
--- a/src/machine/machine.c
+++ b/src/machine/machine.c
@@ -8,6 +8,7 @@
 
 #include "alloc-util.h"
 #include "bus-error.h"
+#include "bus-internal.h"
 #include "bus-locator.h"
 #include "bus-unit-util.h"
 #include "bus-util.h"
@@ -702,6 +703,246 @@ int machine_open_terminal(Machine *m, const char *path, int mode) {
         }
 }
 
+static int machine_bus_new(Machine *m, sd_bus_error *error, sd_bus **ret) {
+        int r;
+
+        assert(m);
+        assert(ret);
+
+        switch (m->class) {
+
+        case MACHINE_HOST:
+                *ret = NULL;
+                return 0;
+
+        case MACHINE_CONTAINER: {
+                _cleanup_(sd_bus_close_unrefp) sd_bus *bus = NULL;
+                char *address;
+
+                r = sd_bus_new(&bus);
+                if (r < 0)
+                        return log_debug_errno(r, "Failed to allocate new DBus: %m");
+
+                if (asprintf(&address, "x-machine-unix:pid=%" PID_PRI, m->leader.pid) < 0)
+                        return -ENOMEM;
+
+                bus->address = address;
+                bus->bus_client = true;
+                bus->trusted = false;
+                bus->runtime_scope = RUNTIME_SCOPE_SYSTEM;
+
+                r = sd_bus_start(bus);
+                if (r == -ENOENT)
+                        return sd_bus_error_set_errnof(error, r, "There is no system bus in container %s.", m->name);
+                if (r < 0)
+                        return r;
+
+                *ret = TAKE_PTR(bus);
+                return 0;
+        }
+
+        default:
+                return -EOPNOTSUPP;
+        }
+}
+
+int machine_start_getty(Machine *m, const char *ptmx_name, sd_bus_error *error) {
+        _cleanup_(sd_bus_flush_close_unrefp) sd_bus *allocated_bus = NULL;
+        sd_bus *container_bus = NULL;
+        const char *p, *getty;
+        int r;
+
+        assert(m);
+        assert(ptmx_name);
+
+        p = path_startswith(ptmx_name, "/dev/pts/");
+        if (!p)
+                return log_debug_errno(SYNTHETIC_ERRNO(EINVAL), "Path of pseudo TTY has unexpected prefix");
+
+        r = machine_bus_new(m, error, &allocated_bus);
+        if (r < 0)
+                return log_debug_errno(r, "Failed to create DBus to machine: %m");
+
+        container_bus = allocated_bus ?: m->manager->bus;
+        getty = strjoina("container-getty@", p, ".service");
+
+        r = bus_call_method(container_bus, bus_systemd_mgr, "StartUnit", error, /* reply = */ NULL, "ss", getty, "replace");
+        if (r < 0)
+                return log_debug_errno(r, "Failed to StartUnit '%s' in container '%s': %m", getty, m->name);
+
+        return 0;
+}
+
+int machine_start_shell(
+                Machine *m,
+                int ptmx_fd,
+                const char *ptmx_name,
+                const char *user,
+                const char *path,
+                char **args,
+                char **env,
+                sd_bus_error *error) {
+        _cleanup_close_ int pty_fd = -EBADF;
+        _cleanup_(sd_bus_message_unrefp) sd_bus_message *tm = NULL;
+        _cleanup_(sd_bus_flush_close_unrefp) sd_bus *allocated_bus = NULL;
+        const char *p, *utmp_id, *unit, *description;
+        sd_bus *container_bus = NULL;
+        int r;
+
+        assert(m);
+        assert(ptmx_fd >= 0);
+        assert(ptmx_name);
+
+        if (isempty(user) || isempty(path) || strv_isempty(args))
+                return -EINVAL;
+
+        p = path_startswith(ptmx_name, "/dev/pts/");
+        utmp_id = path_startswith(ptmx_name, "/dev/");
+        if (!p || !utmp_id)
+                return log_debug_errno(SYNTHETIC_ERRNO(EINVAL), "Path of pseudo TTY has unexpected prefix");
+
+        /* First try to get an fd for the PTY peer via the new racefree ioctl(), directly. Otherwise go via
+         * joining the namespace, because it goes by path */
+        pty_fd = pty_open_peer_racefree(ptmx_fd, O_RDWR|O_NOCTTY|O_CLOEXEC);
+        if (ERRNO_IS_NEG_NOT_SUPPORTED(pty_fd))
+                pty_fd = machine_open_terminal(m, ptmx_name, O_RDWR|O_NOCTTY|O_CLOEXEC);
+        if (pty_fd < 0)
+                return log_debug_errno(pty_fd, "Failed to open terminal: %m");
+
+        r = machine_bus_new(m, error, &allocated_bus);
+        if (r < 0)
+                return log_debug_errno(r, "Failed to create DBus to machine: %m");
+
+        container_bus = allocated_bus ?: m->manager->bus;
+        r = bus_message_new_method_call(container_bus, &tm, bus_systemd_mgr, "StartTransientUnit");
+        if (r < 0)
+                return r;
+
+        /* Name and mode */
+        unit = strjoina("container-shell@", p, ".service");
+        r = sd_bus_message_append(tm, "ss", unit, "fail");
+        if (r < 0)
+                return r;
+
+        /* Properties */
+        r = sd_bus_message_open_container(tm, 'a', "(sv)");
+        if (r < 0)
+                return r;
+
+        description = strjoina("Shell for User ", user);
+        r = sd_bus_message_append(tm,
+                                  "(sv)(sv)(sv)(sv)(sv)(sv)(sv)(sv)(sv)(sv)(sv)(sv)(sv)",
+                                  "Description", "s", description,
+                                  "StandardInputFileDescriptor", "h", pty_fd,
+                                  "StandardOutputFileDescriptor", "h", pty_fd,
+                                  "StandardErrorFileDescriptor", "h", pty_fd,
+                                  "SendSIGHUP", "b", true,
+                                  "IgnoreSIGPIPE", "b", false,
+                                  "KillMode", "s", "mixed",
+                                  "TTYPath", "s", ptmx_name,
+                                  "TTYReset", "b", true,
+                                  "UtmpIdentifier", "s", utmp_id,
+                                  "UtmpMode", "s", "user",
+                                  "PAMName", "s", "login",
+                                  "WorkingDirectory", "s", "-~");
+        if (r < 0)
+                return r;
+
+        r = sd_bus_message_append(tm, "(sv)", "User", "s", user);
+        if (r < 0)
+                return r;
+
+        if (!strv_isempty(env)) {
+                r = sd_bus_message_open_container(tm, 'r', "sv");
+                if (r < 0)
+                        return r;
+
+                r = sd_bus_message_append(tm, "s", "Environment");
+                if (r < 0)
+                        return r;
+
+                r = sd_bus_message_open_container(tm, 'v', "as");
+                if (r < 0)
+                        return r;
+
+                r = sd_bus_message_append_strv(tm, env);
+                if (r < 0)
+                        return r;
+
+                r = sd_bus_message_close_container(tm);
+                if (r < 0)
+                        return r;
+
+                r = sd_bus_message_close_container(tm);
+                if (r < 0)
+                        return r;
+        }
+
+        /* Exec container */
+        r = sd_bus_message_open_container(tm, 'r', "sv");
+        if (r < 0)
+                return r;
+
+        r = sd_bus_message_append(tm, "s", "ExecStart");
+        if (r < 0)
+                return r;
+
+        r = sd_bus_message_open_container(tm, 'v', "a(sasb)");
+        if (r < 0)
+                return r;
+
+        r = sd_bus_message_open_container(tm, 'a', "(sasb)");
+        if (r < 0)
+                return r;
+
+        r = sd_bus_message_open_container(tm, 'r', "sasb");
+        if (r < 0)
+                return r;
+
+        r = sd_bus_message_append(tm, "s", path);
+        if (r < 0)
+                return r;
+
+        r = sd_bus_message_append_strv(tm, args);
+        if (r < 0)
+                return r;
+
+        r = sd_bus_message_append(tm, "b", true);
+        if (r < 0)
+                return r;
+
+        r = sd_bus_message_close_container(tm);
+        if (r < 0)
+                return r;
+
+        r = sd_bus_message_close_container(tm);
+        if (r < 0)
+                return r;
+
+        r = sd_bus_message_close_container(tm);
+        if (r < 0)
+                return r;
+
+        r = sd_bus_message_close_container(tm);
+        if (r < 0)
+                return r;
+
+        r = sd_bus_message_close_container(tm);
+        if (r < 0)
+                return r;
+
+        /* Auxiliary units */
+        r = sd_bus_message_append(tm, "a(sa(sv))", 0);
+        if (r < 0)
+                return r;
+
+        r = sd_bus_call(container_bus, tm, 0, error, NULL);
+        if (r < 0)
+                return r;
+
+        return 0;
+}
+
 void machine_release_unit(Machine *m) {
         assert(m);
 
diff --git a/src/machine/machine.h b/src/machine/machine.h
index debcb7d4b97..58250adb0ee 100644
--- a/src/machine/machine.h
+++ b/src/machine/machine.h
@@ -102,6 +102,8 @@ KillWhom kill_whom_from_string(const char *s) _pure_;
 
 int machine_openpt(Machine *m, int flags, char **ret_slave);
 int machine_open_terminal(Machine *m, const char *path, int mode);
+int machine_start_getty(Machine *m, const char *ptmx_name, sd_bus_error *error);
+int machine_start_shell(Machine *m, int ptmx_fd, const char *ptmx_name, const char *user, const char *path, char **args, char **env, sd_bus_error *error);
 
 int machine_get_uid_shift(Machine *m, uid_t *ret);