machined: make "machinectl copy-to" and "machinectl copy-from" server side operations

This way, any bus client can make use of these calls.

7 files changed, 262 insertions, 128 deletions

diff --git a/src/machine/machine-dbus.c b/src/machine/machine-dbus.c
index eb4b70a614..216c9c1d0d 100644
--- a/src/machine/machine-dbus.c
+++ b/src/machine/machine-dbus.c
@@ -24,6 +24,12 @@
 #include <arpa/inet.h>
 #include <sys/mount.h>
 
+/* When we include libgen.h because we need dirname() we immediately
+ * undefine basename() since libgen.h defines it as a macro to the XDG
+ * version which is really broken. */
+#include <libgen.h>
+#undef basename
+
 #include "bus-util.h"
 #include "bus-label.h"
 #include "strv.h"
@@ -725,6 +731,178 @@ finish:
         return r;
 }
 
+static int machine_operation_done(sd_event_source *s, const siginfo_t *si, void *userdata) {
+        _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
+        MachineOperation *o = userdata;
+        int r;
+
+        assert(o);
+        assert(si);
+
+        o->pid = 0;
+
+        if (si->si_code != CLD_EXITED) {
+                r = sd_bus_error_setf(&error, SD_BUS_ERROR_FAILED, "Client died abnormally.");
+                goto fail;
+        }
+
+        if (si->si_status != EXIT_SUCCESS) {
+                if (read(o->errno_fd, &r, sizeof(r)) == sizeof(r))
+                        r = sd_bus_error_set_errnof(&error, r, "%m");
+                else
+                        r = sd_bus_error_setf(&error, SD_BUS_ERROR_FAILED, "Client failed.");
+
+                goto fail;
+        }
+
+        r = sd_bus_reply_method_return(o->message, NULL);
+        if (r < 0)
+                log_error_errno(r, "Failed to reply to message: %m");
+
+        machine_operation_unref(o);
+        return 0;
+
+fail:
+        r = sd_bus_reply_method_error(o->message, &error);
+        if (r < 0)
+                log_error_errno(r, "Failed to reply to message: %m");
+
+        machine_operation_unref(o);
+        return 0;
+}
+
+int bus_machine_method_copy(sd_bus *bus, sd_bus_message *message, void *userdata, sd_bus_error *error) {
+        const char *src, *dest, *host_path, *container_path, *host_basename, *host_dirname, *container_basename, *container_dirname;
+        _cleanup_close_pair_ int errno_pipe_fd[2] = { -1, -1 };
+        _cleanup_close_ int hostfd = -1;
+        Machine *m = userdata;
+        MachineOperation *o;
+        bool copy_from;
+        pid_t child;
+        char *t;
+        int r;
+
+        if (m->n_operations >= MACHINE_OPERATIONS_MAX)
+                return sd_bus_error_setf(error, SD_BUS_ERROR_LIMITS_EXCEEDED, "Too many ongoing copies.");
+
+        if (m->class != MACHINE_CONTAINER)
+                return sd_bus_error_setf(error, SD_BUS_ERROR_NOT_SUPPORTED, "Copying files is only supported on container machines.");
+
+        r = sd_bus_message_read(message, "ss", &src, &dest);
+        if (r < 0)
+                return r;
+
+        if (!path_is_absolute(src) || !path_is_safe(src))
+                return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Source path must be absolute and not contain ../.");
+
+        if (isempty(dest))
+                dest = src;
+        else if (!path_is_absolute(dest) || !path_is_safe(dest))
+                return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Destination path must be absolute and not contain ../.");
+
+        copy_from = strstr(sd_bus_message_get_member(message), "CopyFrom");
+
+        if (copy_from) {
+                container_path = src;
+                host_path = dest;
+        } else {
+                host_path = src;
+                container_path = dest;
+        }
+
+        host_basename = basename(host_path);
+        t = strdupa(host_path);
+        host_dirname = dirname(t);
+
+        container_basename = basename(container_path);
+        t = strdupa(container_path);
+        container_dirname = dirname(t);
+
+        hostfd = open(host_dirname, O_CLOEXEC|O_RDONLY|O_NOCTTY|O_DIRECTORY);
+        if (r < 0)
+                return sd_bus_error_set_errnof(error, errno, "Failed to open host directory %s: %m", host_dirname);
+
+        if (pipe2(errno_pipe_fd, O_CLOEXEC|O_NONBLOCK) < 0)
+                return sd_bus_error_set_errnof(error, errno, "Failed to create pipe: %m");
+
+        child = fork();
+        if (child < 0)
+                return sd_bus_error_set_errnof(error, errno, "Failed to fork(): %m");
+
+        if (child == 0) {
+                int containerfd;
+                const char *q;
+                int mntfd;
+
+                errno_pipe_fd[0] = safe_close(errno_pipe_fd[0]);
+
+                q = procfs_file_alloca(m->leader, "ns/mnt");
+                mntfd = open(q, O_RDONLY|O_NOCTTY|O_CLOEXEC);
+                if (mntfd < 0) {
+                        r = log_error_errno(errno, "Failed to open mount namespace of leader: %m");
+                        goto child_fail;
+                }
+
+                if (setns(mntfd, CLONE_NEWNS) < 0) {
+                        r = log_error_errno(errno, "Failed to join namespace of leader: %m");
+                        goto child_fail;
+                }
+
+                containerfd = open(container_dirname, O_CLOEXEC|O_RDONLY|O_NOCTTY|O_DIRECTORY);
+                if (containerfd < 0) {
+                        r = log_error_errno(errno, "Failed top open destination directory: %m");
+                        goto child_fail;
+                }
+
+                if (copy_from)
+                        r = copy_tree_at(containerfd, container_basename, hostfd, host_basename, true);
+                else
+                        r = copy_tree_at(hostfd, host_basename, containerfd, container_basename, true);
+
+                hostfd = safe_close(hostfd);
+                containerfd = safe_close(containerfd);
+
+                if (r < 0) {
+                        r = log_error_errno(r, "Failed to copy tree: %m");
+                        goto child_fail;
+                }
+
+                _exit(EXIT_SUCCESS);
+
+        child_fail:
+                (void) write(errno_pipe_fd[1], &r, sizeof(r));
+                errno_pipe_fd[1] = safe_close(errno_pipe_fd[1]);
+
+                _exit(EXIT_FAILURE);
+        }
+
+        errno_pipe_fd[1] = safe_close(errno_pipe_fd[1]);
+
+        /* Copying might take a while, hence install a watch the
+         * child, and return */
+
+        o = new0(MachineOperation, 1);
+        if (!o)
+                return log_oom();
+
+        o->pid = child;
+        o->message = sd_bus_message_ref(message);
+        o->errno_fd = errno_pipe_fd[0];
+        errno_pipe_fd[0] = -1;
+
+        r = sd_event_add_child(m->manager->event, &o->event_source, child, WEXITED, machine_operation_done, o);
+        if (r < 0) {
+                machine_operation_unref(o);
+                return log_oom();
+        }
+
+        LIST_PREPEND(operations, m->operations, o);
+        m->n_operations++;
+        o->machine = m;
+
+        return 1;
+}
+
 const sd_bus_vtable machine_vtable[] = {
         SD_BUS_VTABLE_START(0),
         SD_BUS_PROPERTY("Name", "s", NULL, offsetof(Machine, name), SD_BUS_VTABLE_PROPERTY_CONST),
@@ -745,6 +923,8 @@ const sd_bus_vtable machine_vtable[] = {
         SD_BUS_METHOD("OpenPTY", NULL, "hs", bus_machine_method_open_pty, 0),
         SD_BUS_METHOD("OpenLogin", NULL, "hs", bus_machine_method_open_login, SD_BUS_VTABLE_UNPRIVILEGED),
         SD_BUS_METHOD("BindMount", "ssbb", NULL, bus_machine_method_bind_mount, 0),
+        SD_BUS_METHOD("CopyFrom", "ss", NULL, bus_machine_method_copy, 0),
+        SD_BUS_METHOD("CopyTo", "ss", NULL, bus_machine_method_copy, 0),
         SD_BUS_VTABLE_END
 };
 
diff --git a/src/machine/machine-dbus.h b/src/machine/machine-dbus.h
index 474fec7b10..dc9115d39a 100644
--- a/src/machine/machine-dbus.h
+++ b/src/machine/machine-dbus.h
@@ -37,6 +37,7 @@ int bus_machine_method_get_os_release(sd_bus *bus, sd_bus_message *message, void
 int bus_machine_method_open_pty(sd_bus *bus, sd_bus_message *message, void *userdata, sd_bus_error *error);
 int bus_machine_method_open_login(sd_bus *bus, sd_bus_message *message, void *userdata, sd_bus_error *error);
 int bus_machine_method_bind_mount(sd_bus *bus, sd_bus_message *message, void *userdata, sd_bus_error *error);
+int bus_machine_method_copy(sd_bus *bus, sd_bus_message *message, void *userdata, sd_bus_error *error);
 
 int machine_send_signal(Machine *m, bool new_machine);
 int machine_send_create_reply(Machine *m, sd_bus_error *error);
diff --git a/src/machine/machine.c b/src/machine/machine.c
index 223eb0f364..edd244f30d 100644
--- a/src/machine/machine.c
+++ b/src/machine/machine.c
@@ -74,6 +74,9 @@ fail:
 void machine_free(Machine *m) {
         assert(m);
 
+        while (m->operations)
+                machine_operation_unref(m->operations);
+
         if (m->in_gc_queue)
                 LIST_REMOVE(gc_queue, m->manager->machine_gc_queue, m);
 
@@ -501,6 +504,28 @@ int machine_kill(Machine *m, KillWho who, int signo) {
         return manager_kill_unit(m->manager, m->unit, signo, NULL);
 }
 
+MachineOperation *machine_operation_unref(MachineOperation *o) {
+        if (!o)
+                return NULL;
+
+        sd_event_source_unref(o->event_source);
+
+        safe_close(o->errno_fd);
+
+        if (o->pid > 1)
+                (void) kill(o->pid, SIGKILL);
+
+        sd_bus_message_unref(o->message);
+
+        if (o->machine) {
+                LIST_REMOVE(operations, o->machine->operations, o);
+                o->machine->n_operations--;
+        }
+
+        free(o);
+        return NULL;
+}
+
 static const char* const machine_class_table[_MACHINE_CLASS_MAX] = {
         [MACHINE_CONTAINER] = "container",
         [MACHINE_VM] = "vm"
diff --git a/src/machine/machine.h b/src/machine/machine.h
index 4827ba332f..94dbac0160 100644
--- a/src/machine/machine.h
+++ b/src/machine/machine.h
@@ -22,6 +22,7 @@
 ***/
 
 typedef struct Machine Machine;
+typedef struct MachineOperation MachineOperation;
 typedef enum KillWho KillWho;
 
 #include "list.h"
@@ -50,6 +51,17 @@ enum KillWho {
         _KILL_WHO_INVALID = -1
 };
 
+#define MACHINE_OPERATIONS_MAX 64
+
+struct MachineOperation {
+        Machine *machine;
+        pid_t pid;
+        sd_bus_message *message;
+        int errno_fd;
+        sd_event_source *event_source;
+        LIST_FIELDS(MachineOperation, operations);
+};
+
 struct Machine {
         Manager *manager;
 
@@ -79,6 +91,9 @@ struct Machine {
         unsigned n_netif;
 
         LIST_FIELDS(Machine, gc_queue);
+
+        MachineOperation *operations;
+        unsigned n_operations;
 };
 
 Machine* machine_new(Manager *manager, const char *name);
@@ -93,6 +108,8 @@ int machine_kill(Machine *m, KillWho who, int signo);
 
 MachineState machine_get_state(Machine *u);
 
+MachineOperation *machine_operation_unref(MachineOperation *o);
+
 const char* machine_class_to_string(MachineClass t) _const_;
 MachineClass machine_class_from_string(const char *s) _pure_;
 
diff --git a/src/machine/machinectl.c b/src/machine/machinectl.c
index c1cc5e7eb5..ea6db4d18b 100644
--- a/src/machine/machinectl.c
+++ b/src/machine/machinectl.c
@@ -32,12 +32,6 @@
 #include <net/if.h>
 #include <sys/mount.h>
 
-/* When we include libgen.h because we need dirname() we immediately
- * undefine basename() since libgen.h defines it as a macro to the XDG
- * version which is really broken. */
-#include <libgen.h>
-#undef basename
-
 #include "sd-bus.h"
 #include "log.h"
 #include "util.h"
@@ -1002,141 +996,33 @@ static int terminate_machine(int argc, char *argv[], void *userdata) {
         return 0;
 }
 
-static int machine_get_leader(sd_bus *bus, const char *name, pid_t *ret) {
+static int copy_files(int argc, char *argv[], void *userdata) {
         _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
-        _cleanup_bus_message_unref_ sd_bus_message *reply = NULL, *reply2 = NULL;
-        const char *object;
-        uint32_t leader;
+        sd_bus *bus = userdata;
+        bool copy_from;
         int r;
 
         assert(bus);
-        assert(name);
-        assert(ret);
+
+        copy_from = streq(argv[0], "copy-from");
 
         r = sd_bus_call_method(
                         bus,
                         "org.freedesktop.machine1",
                         "/org/freedesktop/machine1",
                         "org.freedesktop.machine1.Manager",
-                        "GetMachine",
+                        copy_from ? "CopyFromMachine" : "CopyToMachine",
                         &error,
-                        &reply,
-                        "s", name);
+                        NULL,
+                        "sss",
+                        argv[1],
+                        argv[2],
+                        argv[3]);
         if (r < 0) {
-                log_error("Could not get path to machine: %s", bus_error_message(&error, -r));
+                log_error("Failed to copy: %s", bus_error_message(&error, -r));
                 return r;
         }
 
-        r = sd_bus_message_read(reply, "o", &object);
-        if (r < 0)
-                return bus_log_parse_error(r);
-
-        r = sd_bus_get_property(
-                        bus,
-                        "org.freedesktop.machine1",
-                        object,
-                        "org.freedesktop.machine1.Machine",
-                        "Leader",
-                        &error,
-                        &reply2,
-                        "u");
-        if (r < 0)
-                return log_error_errno(r, "Failed to retrieve PID of leader: %m");
-
-        r = sd_bus_message_read(reply2, "u", &leader);
-        if (r < 0)
-                return bus_log_parse_error(r);
-
-        *ret = leader;
-        return 0;
-}
-
-static int copy_files(int argc, char *argv[], void *userdata) {
-        char *dest, *host_path, *container_path, *host_dirname, *host_basename, *container_dirname, *container_basename, *t;
-        _cleanup_close_ int hostfd = -1;
-        sd_bus *bus = userdata;
-        pid_t child, leader;
-        bool copy_from;
-        siginfo_t si;
-        int r;
-
-        assert(bus);
-
-        copy_from = streq(argv[0], "copy-from");
-        dest = argv[3] ?: argv[2];
-        host_path = strdupa(copy_from ? dest : argv[2]);
-        container_path = strdupa(copy_from ? argv[2] : dest);
-
-        if (!path_is_absolute(container_path)) {
-                log_error("Container path not absolute.");
-                return -EINVAL;
-        }
-
-        t = strdupa(host_path);
-        host_basename = basename(t);
-        host_dirname = dirname(host_path);
-
-        t = strdupa(container_path);
-        container_basename = basename(t);
-        container_dirname = dirname(container_path);
-
-        r = machine_get_leader(bus, argv[1], &leader);
-        if (r < 0)
-                return r;
-
-        hostfd = open(host_dirname, O_CLOEXEC|O_RDONLY|O_NOCTTY|O_DIRECTORY);
-        if (r < 0)
-                return log_error_errno(errno, "Failed to open source directory: %m");
-
-        child = fork();
-        if (child < 0)
-                return log_error_errno(errno, "Failed to fork(): %m");
-
-        if (child == 0) {
-                int containerfd;
-                const char *q;
-                int mntfd;
-
-                q = procfs_file_alloca(leader, "ns/mnt");
-                mntfd = open(q, O_RDONLY|O_NOCTTY|O_CLOEXEC);
-                if (mntfd < 0) {
-                        log_error_errno(errno, "Failed to open mount namespace of leader: %m");
-                        _exit(EXIT_FAILURE);
-                }
-
-                if (setns(mntfd, CLONE_NEWNS) < 0) {
-                        log_error_errno(errno, "Failed to join namespace of leader: %m");
-                        _exit(EXIT_FAILURE);
-                }
-
-                containerfd = open(container_dirname, O_CLOEXEC|O_RDONLY|O_NOCTTY|O_DIRECTORY);
-                if (containerfd < 0) {
-                        log_error_errno(errno, "Failed top open destination directory: %m");
-                        _exit(EXIT_FAILURE);
-                }
-
-                if (copy_from)
-                        r = copy_tree_at(containerfd, container_basename, hostfd, host_basename, true);
-                else
-                        r = copy_tree_at(hostfd, host_basename, containerfd, container_basename, true);
-                if (r < 0) {
-                        log_error_errno(errno, "Failed to copy tree: %m");
-                        _exit(EXIT_FAILURE);
-                }
-
-                _exit(EXIT_SUCCESS);
-        }
-
-        r = wait_for_terminate(child, &si);
-        if (r < 0)
-                return log_error_errno(r, "Failed to wait for client: %m");
-        if (si.si_code != CLD_EXITED) {
-                log_error("Client died abnormally.");
-                return -EIO;
-        }
-        if (si.si_status != EXIT_SUCCESS)
-                return -EIO;
-
         return 0;
 }
 
diff --git a/src/machine/machined-dbus.c b/src/machine/machined-dbus.c
index 2b06d994a8..155146b938 100644
--- a/src/machine/machined-dbus.c
+++ b/src/machine/machined-dbus.c
@@ -580,6 +580,27 @@ static int method_bind_mount_machine(sd_bus *bus, sd_bus_message *message, void
         return bus_machine_method_bind_mount(bus, message, machine, error);
 }
 
+static int method_copy_machine(sd_bus *bus, sd_bus_message *message, void *userdata, sd_bus_error *error) {
+        Manager *m = userdata;
+        Machine *machine;
+        const char *name;
+        int r;
+
+        assert(bus);
+        assert(message);
+        assert(m);
+
+        r = sd_bus_message_read(message, "s", &name);
+        if (r < 0)
+                return r;
+
+        machine = hashmap_get(m->machines, name);
+        if (!machine)
+                return sd_bus_error_setf(error, BUS_ERROR_NO_SUCH_MACHINE, "No machine '%s' known", name);
+
+        return bus_machine_method_copy(bus, message, machine, error);
+}
+
 static int method_remove_image(sd_bus *bus, sd_bus_message *message, void *userdata, sd_bus_error *error) {
         _cleanup_(image_unrefp) Image* i = NULL;
         const char *name;
@@ -683,17 +704,19 @@ const sd_bus_vtable manager_vtable[] = {
         SD_BUS_METHOD("CreateMachineWithNetwork", "sayssusaia(sv)", "o", method_create_machine_with_network, 0),
         SD_BUS_METHOD("RegisterMachine", "sayssus", "o", method_register_machine, 0),
         SD_BUS_METHOD("RegisterMachineWithNetwork", "sayssusai", "o", method_register_machine_with_network, 0),
-        SD_BUS_METHOD("KillMachine", "ssi", NULL, method_kill_machine, SD_BUS_VTABLE_CAPABILITY(CAP_KILL)),
         SD_BUS_METHOD("TerminateMachine", "s", NULL, method_terminate_machine, SD_BUS_VTABLE_CAPABILITY(CAP_KILL)),
+        SD_BUS_METHOD("KillMachine", "ssi", NULL, method_kill_machine, SD_BUS_VTABLE_CAPABILITY(CAP_KILL)),
         SD_BUS_METHOD("GetMachineAddresses", "s", "a(iay)", method_get_machine_addresses, SD_BUS_VTABLE_UNPRIVILEGED),
         SD_BUS_METHOD("GetMachineOSRelease", "s", "a{ss}", method_get_machine_os_release, SD_BUS_VTABLE_UNPRIVILEGED),
         SD_BUS_METHOD("OpenMachinePTY", "s", "hs", method_open_machine_pty, 0),
         SD_BUS_METHOD("OpenMachineLogin", "s", "hs", method_open_machine_login, SD_BUS_VTABLE_UNPRIVILEGED),
+        SD_BUS_METHOD("BindMountMachine", "sssbb", NULL, method_bind_mount_machine, 0),
+        SD_BUS_METHOD("CopyFromMachine", "sss", NULL, method_copy_machine, 0),
+        SD_BUS_METHOD("CopyToMachine", "sss", NULL, method_copy_machine, 0),
         SD_BUS_METHOD("RemoveImage", "s", NULL, method_remove_image, 0),
         SD_BUS_METHOD("RenameImage", "ss", NULL, method_rename_image, 0),
         SD_BUS_METHOD("CloneImage", "ssb", NULL, method_clone_image, 0),
         SD_BUS_METHOD("MarkImageReadOnly", "sb", NULL, method_mark_image_read_only, 0),
-        SD_BUS_METHOD("BindMountMachine", "sssbb", NULL, method_bind_mount_machine, 0),
         SD_BUS_SIGNAL("MachineNew", "so", 0),
         SD_BUS_SIGNAL("MachineRemoved", "so", 0),
         SD_BUS_VTABLE_END
diff --git a/src/machine/machined.c b/src/machine/machined.c
index 6877c2b313..1373362e9d 100644
--- a/src/machine/machined.c
+++ b/src/machine/machined.c
@@ -325,6 +325,8 @@ int main(int argc, char *argv[]) {
          * check stays in. */
         mkdir_label("/run/systemd/machines", 0755);
 
+        assert_se(sigprocmask_many(SIG_BLOCK, SIGCHLD, -1) >= 0);
+
         m = manager_new();
         if (!m) {
                 r = log_oom();