machined: allow registering host-side network interfaces for communication with containers

4 files changed, 127 insertions, 7 deletions

diff --git a/src/machine/machine-dbus.c b/src/machine/machine-dbus.c
index 3741485a7b..72e0a701bf 100644
--- a/src/machine/machine-dbus.c
+++ b/src/machine/machine-dbus.c
@@ -83,6 +83,31 @@ static int property_get_state(
         return 1;
 }
 
+static int property_get_netif(
+                sd_bus *bus,
+                const char *path,
+                const char *interface,
+                const char *property,
+                sd_bus_message *reply,
+                void *userdata,
+                sd_bus_error *error) {
+
+        Machine *m = userdata;
+        int r;
+
+        assert(bus);
+        assert(reply);
+        assert(m);
+
+        assert_cc(sizeof(int) == sizeof(int32_t));
+
+        r = sd_bus_message_append_array(reply, 'i', m->netif, m->n_netif * sizeof(int));
+        if (r < 0)
+                return r;
+
+        return 1;
+}
+
 static BUS_DEFINE_PROPERTY_GET_ENUM(property_get_class, machine_class, MachineClass);
 
 int bus_machine_method_terminate(sd_bus *bus, sd_bus_message *message, void *userdata, sd_bus_error *error) {
@@ -376,6 +401,7 @@ const sd_bus_vtable machine_vtable[] = {
         SD_BUS_PROPERTY("Leader", "u", NULL, offsetof(Machine, leader), SD_BUS_VTABLE_PROPERTY_CONST),
         SD_BUS_PROPERTY("Class", "s", property_get_class, offsetof(Machine, class), SD_BUS_VTABLE_PROPERTY_CONST),
         SD_BUS_PROPERTY("RootDirectory", "s", NULL, offsetof(Machine, root_directory), SD_BUS_VTABLE_PROPERTY_CONST),
+        SD_BUS_PROPERTY("NetworkInterfaces", "ai", property_get_netif, 0, SD_BUS_VTABLE_PROPERTY_CONST),
         SD_BUS_PROPERTY("State", "s", property_get_state, 0, 0),
         SD_BUS_METHOD("Terminate", NULL, NULL, bus_machine_method_terminate, SD_BUS_VTABLE_CAPABILITY(CAP_KILL)),
         SD_BUS_METHOD("Kill", "si", NULL, bus_machine_method_kill, SD_BUS_VTABLE_CAPABILITY(CAP_KILL)),
diff --git a/src/machine/machine.c b/src/machine/machine.c
index cf38e3fb94..0ed18d74ec 100644
--- a/src/machine/machine.c
+++ b/src/machine/machine.c
@@ -94,6 +94,7 @@ void machine_free(Machine *m) {
         free(m->state_file);
         free(m->service);
         free(m->root_directory);
+        free(m->netif);
         free(m);
 }
 
@@ -176,6 +177,21 @@ int machine_save(Machine *m) {
                         m->timestamp.realtime,
                         m->timestamp.monotonic);
 
+        if (m->n_netif > 0) {
+                unsigned i;
+
+                fputs("NETIF=", f);
+
+                for (i = 0; i < m->n_netif; i++) {
+                        if (i != 0)
+                                fputc(' ', f);
+
+                        fprintf(f, "%i", m->netif[i]);
+                }
+
+                fputc('\n', f);
+        }
+
         r = fflush_and_check(f);
         if (r < 0)
                 goto finish;
@@ -222,7 +238,7 @@ static void machine_unlink(Machine *m) {
 }
 
 int machine_load(Machine *m) {
-        _cleanup_free_ char *realtime = NULL, *monotonic = NULL, *id = NULL, *leader = NULL, *class = NULL;
+        _cleanup_free_ char *realtime = NULL, *monotonic = NULL, *id = NULL, *leader = NULL, *class = NULL, *netif = NULL;
         int r;
 
         assert(m);
@@ -237,6 +253,7 @@ int machine_load(Machine *m) {
                            "CLASS",     &class,
                            "REALTIME",  &realtime,
                            "MONOTONIC", &monotonic,
+                           "NETIF",     &netif,
                            NULL);
         if (r < 0) {
                 if (r == -ENOENT)
@@ -272,6 +289,35 @@ int machine_load(Machine *m) {
                         m->timestamp.monotonic = l;
         }
 
+        if (netif) {
+                size_t l, allocated = 0, nr = 0;
+                char *w, *state;
+                int *ni = NULL;
+
+                FOREACH_WORD(w, l, netif, state) {
+                        char buf[l+1];
+                        int ifi;
+
+                        *(char*) (mempcpy(buf, w, l)) = 0;
+
+                        if (safe_atoi(buf, &ifi) < 0)
+                                continue;
+                        if (ifi <= 0)
+                                continue;
+
+                        if (!GREEDY_REALLOC(ni, allocated, nr+1)) {
+                                free(ni);
+                                return log_oom();
+                        }
+
+                        ni[nr++] = ifi;
+                }
+
+                free(m->netif);
+                m->netif = ni;
+                m->n_netif = nr;
+        }
+
         return r;
 }
 
diff --git a/src/machine/machine.h b/src/machine/machine.h
index fa9262d52c..5c6366554a 100644
--- a/src/machine/machine.h
+++ b/src/machine/machine.h
@@ -76,6 +76,9 @@ struct Machine {
 
         sd_bus_message *create_message;
 
+        int *netif;
+        unsigned n_netif;
+
         LIST_FIELDS(Machine, gc_queue);
 };
 
diff --git a/src/machine/machined-dbus.c b/src/machine/machined-dbus.c
index a041444b73..1b9449a2b7 100644
--- a/src/machine/machined-dbus.c
+++ b/src/machine/machined-dbus.c
@@ -151,14 +151,15 @@ static int method_list_machines(sd_bus *bus, sd_bus_message *message, void *user
         return sd_bus_send(bus, reply, NULL);
 }
 
-static int method_create_or_register_machine(Manager *manager, sd_bus_message *message, Machine **_m, sd_bus_error *error) {
+static int method_create_or_register_machine(Manager *manager, sd_bus_message *message, bool read_network, Machine **_m, sd_bus_error *error) {
         const char *name, *service, *class, *root_directory;
+        const int32_t *netif = NULL;
         MachineClass c;
         uint32_t leader;
         sd_id128_t id;
         const void *v;
         Machine *m;
-        size_t n;
+        size_t n, n_netif = 0;
         int r;
 
         assert(manager);
@@ -185,6 +186,21 @@ static int method_create_or_register_machine(Manager *manager, sd_bus_message *m
         if (r < 0)
                 return r;
 
+        if (read_network) {
+                size_t i;
+
+                r = sd_bus_message_read_array(message, 'i', (const void**) &netif, &n_netif);
+                if (r < 0)
+                        return r;
+
+                n_netif /= sizeof(int32_t);
+
+                for (i = 0; i < n_netif; i++) {
+                        if (netif[i] <= 0)
+                                return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Invalid network interface index %i", netif[i]);
+                }
+        }
+
         if (isempty(class))
                 c = _MACHINE_CLASS_INVALID;
         else {
@@ -240,6 +256,17 @@ static int method_create_or_register_machine(Manager *manager, sd_bus_message *m
                 }
         }
 
+        if (n_netif > 0) {
+                assert_cc(sizeof(int32_t) == sizeof(int));
+                m->netif = memdup(netif, sizeof(int32_t) * n_netif);
+                if (!m->netif) {
+                        r = -ENOMEM;
+                        goto fail;
+                }
+
+                m->n_netif = n_netif;
+        }
+
         *_m = m;
 
         return 1;
@@ -249,12 +276,12 @@ fail:
         return r;
 }
 
-static int method_create_machine(sd_bus *bus, sd_bus_message *message, void *userdata, sd_bus_error *error) {
+static int method_create_machine_internal(sd_bus *bus, sd_bus_message *message, bool read_network, void *userdata, sd_bus_error *error) {
         Manager *manager = userdata;
         Machine *m = NULL;
         int r;
 
-        r = method_create_or_register_machine(manager, message, &m, error);
+        r = method_create_or_register_machine(manager, message, read_network, &m, error);
         if (r < 0)
                 return r;
 
@@ -274,13 +301,21 @@ fail:
         return r;
 }
 
-static int method_register_machine(sd_bus *bus, sd_bus_message *message, void *userdata, sd_bus_error *error) {
+static int method_create_machine_with_network(sd_bus *bus, sd_bus_message *message, void *userdata, sd_bus_error *error) {
+        return method_create_machine_internal(bus, message, true, userdata, error);
+}
+
+static int method_create_machine(sd_bus *bus, sd_bus_message *message, void *userdata, sd_bus_error *error) {
+        return method_create_machine_internal(bus, message, false, userdata, error);
+}
+
+static int method_register_machine_internal(sd_bus *bus, sd_bus_message *message, bool read_network, void *userdata, sd_bus_error *error) {
         Manager *manager = userdata;
         _cleanup_free_ char *p = NULL;
         Machine *m = NULL;
         int r;
 
-        r = method_create_or_register_machine(manager, message, &m, error);
+        r = method_create_or_register_machine(manager, message, read_network, &m, error);
         if (r < 0)
                 return r;
 
@@ -309,6 +344,14 @@ fail:
         return r;
 }
 
+static int method_register_machine_with_network(sd_bus *bus, sd_bus_message *message, void *userdata, sd_bus_error *error) {
+        return method_register_machine_internal(bus, message, true, userdata, error);
+}
+
+static int method_register_machine(sd_bus *bus, sd_bus_message *message, void *userdata, sd_bus_error *error) {
+        return method_register_machine_internal(bus, message, false, userdata, error);
+}
+
 static int method_terminate_machine(sd_bus *bus, sd_bus_message *message, void *userdata, sd_bus_error *error) {
         Manager *m = userdata;
         Machine *machine;
@@ -400,6 +443,8 @@ const sd_bus_vtable manager_vtable[] = {
         SD_BUS_METHOD("ListMachines", NULL, "a(ssso)", method_list_machines, SD_BUS_VTABLE_UNPRIVILEGED),
         SD_BUS_METHOD("CreateMachine", "sayssusa(sv)", "o", method_create_machine, 0),
         SD_BUS_METHOD("RegisterMachine", "sayssus", "o", method_register_machine, 0),
+        SD_BUS_METHOD("CreateMachineWithNetwork", "sayssusaia(sv)", "o", method_create_machine_with_network, 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("GetMachineAddresses", "s", "a(yay)", method_get_machine_addresses, SD_BUS_VTABLE_UNPRIVILEGED),