portabled: add --extension parameter for layered images support

Add an --extension parameter to portablectl, and new DBUS methods
to attach/detach/reattach/inspect.
Allows to append separate images on top of the root directory (os-release
will be searched in there) and mount the images using an overlay-like
setup (unit files will be searched in there) using the new ExtensionImages
service option.

1 files changed, 171 insertions, 27 deletions

diff --git a/src/portable/portabled-image-bus.c b/src/portable/portabled-image-bus.c
index 8332332c91..88d8f914e0 100644
--- a/src/portable/portabled-image-bus.c
+++ b/src/portable/portabled-image-bus.c
@@ -75,20 +75,22 @@ static int bus_image_method_get_os_release(sd_bus_message *message, void *userda
 static int append_fd(sd_bus_message *m, PortableMetadata *d) {
         _cleanup_fclose_ FILE *f = NULL;
         _cleanup_free_ char *buf = NULL;
-        size_t n;
+        size_t n = 0;
         int r;
 
         assert(m);
-        assert(d);
-        assert(d->fd >= 0);
 
-        f = take_fdopen(&d->fd, "r");
-        if (!f)
-                return -errno;
+        if (d) {
+                assert(d->fd >= 0);
 
-        r = read_full_stream(f, &buf, &n);
-        if (r < 0)
-                return r;
+                f = take_fdopen(&d->fd, "r");
+                if (!f)
+                        return -errno;
+
+                r = read_full_stream(f, &buf, &n);
+                if (r < 0)
+                        return r;
+        }
 
         return sd_bus_message_append_array(m, 'y', buf, n);
 }
@@ -101,10 +103,12 @@ int bus_image_common_get_metadata(
                 sd_bus_error *error) {
 
         _cleanup_(portable_metadata_unrefp) PortableMetadata *os_release = NULL;
+        _cleanup_strv_free_ char **matches = NULL, **extension_images = NULL;
         _cleanup_hashmap_free_ Hashmap *unit_files = NULL;
         _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL;
         _cleanup_free_ PortableMetadata **sorted = NULL;
-        _cleanup_strv_free_ char **matches = NULL;
+        /* Unused for now, but added to the DBUS methods for future-proofing */
+        uint64_t input_flags = 0;
         size_t i;
         int r;
 
@@ -116,10 +120,29 @@ int bus_image_common_get_metadata(
                 m = image->userdata;
         }
 
+        if (sd_bus_message_is_method_call(message, NULL, "GetImageMetadataWithExtensions") ||
+            sd_bus_message_is_method_call(message, NULL, "GetMetadataWithExtensions")) {
+                r = sd_bus_message_read_strv(message, &extension_images);
+                if (r < 0)
+                        return r;
+        }
+
         r = sd_bus_message_read_strv(message, &matches);
         if (r < 0)
                 return r;
 
+        if (sd_bus_message_is_method_call(message, NULL, "GetImageMetadataWithExtensions") ||
+            sd_bus_message_is_method_call(message, NULL, "GetMetadataWithExtensions")) {
+                r = sd_bus_message_read(message, "t", &input_flags);
+                if (r < 0)
+                        return r;
+                /* Let clients know that this version doesn't support any flags */
+                if (input_flags != 0)
+                        return sd_bus_reply_method_errorf(message, SD_BUS_ERROR_INVALID_ARGS,
+                                                          "Invalid 'flags' parameter '%" PRIu64 "'",
+                                                          input_flags);
+        }
+
         r = bus_image_acquire(m,
                               message,
                               name_or_path,
@@ -136,6 +159,7 @@ int bus_image_common_get_metadata(
         r = portable_extract(
                         image->path,
                         matches,
+                        extension_images,
                         &os_release,
                         &unit_files,
                         error);
@@ -223,12 +247,12 @@ int bus_image_common_attach(
                 Image *image,
                 sd_bus_error *error) {
 
-        _cleanup_strv_free_ char **matches = NULL;
+        _cleanup_strv_free_ char **matches = NULL, **extension_images = NULL;
         PortableChange *changes = NULL;
         PortableFlags flags = 0;
         const char *profile, *copy_mode;
         size_t n_changes = 0;
-        int runtime, r;
+        int r;
 
         assert(message);
         assert(name_or_path || image);
@@ -238,14 +262,44 @@ int bus_image_common_attach(
                 m = image->userdata;
         }
 
+        if (sd_bus_message_is_method_call(message, NULL, "AttachImageWithExtensions") ||
+            sd_bus_message_is_method_call(message, NULL, "AttachWithExtensions")) {
+                r = sd_bus_message_read_strv(message, &extension_images);
+                if (r < 0)
+                        return r;
+        }
+
         r = sd_bus_message_read_strv(message, &matches);
         if (r < 0)
                 return r;
 
-        r = sd_bus_message_read(message, "sbs", &profile, &runtime, &copy_mode);
+        r = sd_bus_message_read(message, "s", &profile);
         if (r < 0)
                 return r;
 
+        if (sd_bus_message_is_method_call(message, NULL, "AttachImageWithExtensions") ||
+            sd_bus_message_is_method_call(message, NULL, "AttachWithExtensions")) {
+                uint64_t input_flags = 0;
+
+                r = sd_bus_message_read(message, "st", &copy_mode, &input_flags);
+                if (r < 0)
+                        return r;
+                if ((input_flags & ~_PORTABLE_MASK_PUBLIC) != 0)
+                        return sd_bus_reply_method_errorf(message, SD_BUS_ERROR_INVALID_ARGS,
+                                                          "Invalid 'flags' parameter '%" PRIu64 "'",
+                                                          input_flags);
+                flags |= input_flags;
+        } else {
+                int runtime;
+
+                r = sd_bus_message_read(message, "bs", &runtime, &copy_mode);
+                if (r < 0)
+                        return r;
+
+                if (runtime)
+                        flags |= PORTABLE_RUNTIME;
+        }
+
         if (streq(copy_mode, "symlink"))
                 flags |= PORTABLE_PREFER_SYMLINK;
         else if (streq(copy_mode, "copy"))
@@ -253,9 +307,6 @@ int bus_image_common_attach(
         else if (!isempty(copy_mode))
                 return sd_bus_reply_method_errorf(message, SD_BUS_ERROR_INVALID_ARGS, "Unknown copy mode '%s'", copy_mode);
 
-        if (runtime)
-                flags |= PORTABLE_RUNTIME;
-
         r = bus_image_acquire(m,
                               message,
                               name_or_path,
@@ -274,6 +325,7 @@ int bus_image_common_attach(
                         image->path,
                         matches,
                         profile,
+                        extension_images,
                         flags,
                         &changes,
                         &n_changes,
@@ -297,19 +349,46 @@ static int bus_image_method_detach(
                 void *userdata,
                 sd_bus_error *error) {
 
+        _cleanup_strv_free_ char **extension_images = NULL;
         PortableChange *changes = NULL;
         Image *image = userdata;
         Manager *m = image->userdata;
+        PortableFlags flags = 0;
         size_t n_changes = 0;
-        int r, runtime;
+        int r;
 
         assert(message);
         assert(image);
         assert(m);
 
-        r = sd_bus_message_read(message, "b", &runtime);
-        if (r < 0)
-                return r;
+        if (sd_bus_message_is_method_call(message, NULL, "DetachWithExtensions")) {
+                r = sd_bus_message_read_strv(message, &extension_images);
+                if (r < 0)
+                        return r;
+        }
+
+        if (sd_bus_message_is_method_call(message, NULL, "DetachWithExtensions")) {
+                uint64_t input_flags = 0;
+
+                r = sd_bus_message_read(message, "t", &input_flags);
+                if (r < 0)
+                        return r;
+
+                if ((input_flags & ~_PORTABLE_MASK_PUBLIC) != 0)
+                        return sd_bus_reply_method_errorf(message, SD_BUS_ERROR_INVALID_ARGS,
+                                                          "Invalid 'flags' parameter '%" PRIu64 "'",
+                                                          input_flags);
+                flags |= input_flags;
+        } else {
+                int runtime;
+
+                r = sd_bus_message_read(message, "b", &runtime);
+                if (r < 0)
+                        return r;
+
+                if (runtime)
+                        flags |= PORTABLE_RUNTIME;
+        }
 
         r = bus_verify_polkit_async(
                         message,
@@ -328,7 +407,8 @@ static int bus_image_method_detach(
         r = portable_detach(
                         sd_bus_message_get_bus(message),
                         image->path,
-                        runtime ? PORTABLE_RUNTIME : 0,
+                        extension_images,
+                        flags,
                         &changes,
                         &n_changes,
                         error);
@@ -510,10 +590,10 @@ int bus_image_common_reattach(
 
         PortableChange *changes_detached = NULL, *changes_attached = NULL, *changes_gone = NULL;
         size_t n_changes_detached = 0, n_changes_attached = 0, n_changes_gone = 0;
-        _cleanup_strv_free_ char **matches = NULL;
+        _cleanup_strv_free_ char **matches = NULL, **extension_images = NULL;
         PortableFlags flags = PORTABLE_REATTACH;
         const char *profile, *copy_mode;
-        int runtime, r;
+        int r;
 
         assert(message);
         assert(name_or_path || image);
@@ -523,14 +603,45 @@ int bus_image_common_reattach(
                 m = image->userdata;
         }
 
+        if (sd_bus_message_is_method_call(message, NULL, "ReattachImageWithExtensions") ||
+            sd_bus_message_is_method_call(message, NULL, "ReattachWithExtensions")) {
+                r = sd_bus_message_read_strv(message, &extension_images);
+                if (r < 0)
+                        return r;
+        }
+
         r = sd_bus_message_read_strv(message, &matches);
         if (r < 0)
                 return r;
 
-        r = sd_bus_message_read(message, "sbs", &profile, &runtime, &copy_mode);
+        r = sd_bus_message_read(message, "s", &profile);
         if (r < 0)
                 return r;
 
+        if (sd_bus_message_is_method_call(message, NULL, "ReattachImageWithExtensions") ||
+            sd_bus_message_is_method_call(message, NULL, "ReattachWithExtensions")) {
+                uint64_t input_flags = 0;
+
+                r = sd_bus_message_read(message, "st", &copy_mode, &input_flags);
+                if (r < 0)
+                        return r;
+
+                if ((input_flags & ~_PORTABLE_MASK_PUBLIC) != 0)
+                        return sd_bus_reply_method_errorf(message, SD_BUS_ERROR_INVALID_ARGS,
+                                                          "Invalid 'flags' parameter '%" PRIu64 "'",
+                                                          input_flags);
+                flags |= input_flags;
+        } else {
+                int runtime;
+
+                r = sd_bus_message_read(message, "bs", &runtime, &copy_mode);
+                if (r < 0)
+                        return r;
+
+                if (runtime)
+                        flags |= PORTABLE_RUNTIME;
+        }
+
         if (streq(copy_mode, "symlink"))
                 flags |= PORTABLE_PREFER_SYMLINK;
         else if (streq(copy_mode, "copy"))
@@ -538,9 +649,6 @@ int bus_image_common_reattach(
         else if (!isempty(copy_mode))
                 return sd_bus_reply_method_errorf(message, SD_BUS_ERROR_INVALID_ARGS, "Unknown copy mode '%s'", copy_mode);
 
-        if (runtime)
-                flags |= PORTABLE_RUNTIME;
-
         r = bus_image_acquire(m,
                               message,
                               name_or_path,
@@ -557,6 +665,7 @@ int bus_image_common_reattach(
         r = portable_detach(
                         sd_bus_message_get_bus(message),
                         image->path,
+                        extension_images,
                         flags,
                         &changes_detached,
                         &n_changes_detached,
@@ -569,6 +678,7 @@ int bus_image_common_reattach(
                         image->path,
                         matches,
                         profile,
+                        extension_images,
                         flags,
                         &changes_attached,
                         &n_changes_attached,
@@ -721,6 +831,15 @@ const sd_bus_vtable image_vtable[] = {
                                               "a{say}", units),
                                 bus_image_method_get_metadata,
                                 SD_BUS_VTABLE_UNPRIVILEGED),
+        SD_BUS_METHOD_WITH_ARGS("GetMetadataWithExtensions",
+                                SD_BUS_ARGS("as", extensions,
+                                            "as", matches,
+                                            "t", flags),
+                                SD_BUS_RESULT("s", image,
+                                              "ay", os_release,
+                                              "a{say}", units),
+                                bus_image_method_get_metadata,
+                                SD_BUS_VTABLE_UNPRIVILEGED),
         SD_BUS_METHOD_WITH_ARGS("GetState",
                                 SD_BUS_NO_ARGS,
                                 SD_BUS_RESULT("s", state),
@@ -734,11 +853,26 @@ const sd_bus_vtable image_vtable[] = {
                                 SD_BUS_RESULT("a(sss)", changes),
                                 bus_image_method_attach,
                                 SD_BUS_VTABLE_UNPRIVILEGED),
+        SD_BUS_METHOD_WITH_ARGS("AttachWithExtensions",
+                                SD_BUS_ARGS("as", extensions,
+                                            "as", matches,
+                                            "s", profile,
+                                            "s", copy_mode,
+                                            "t", flags),
+                                SD_BUS_RESULT("a(sss)", changes),
+                                bus_image_method_attach,
+                                SD_BUS_VTABLE_UNPRIVILEGED),
         SD_BUS_METHOD_WITH_ARGS("Detach",
                                 SD_BUS_ARGS("b", runtime),
                                 SD_BUS_RESULT("a(sss)", changes),
                                 bus_image_method_detach,
                                 SD_BUS_VTABLE_UNPRIVILEGED),
+        SD_BUS_METHOD_WITH_ARGS("DetachWithExtensions",
+                                SD_BUS_ARGS("as", extensions,
+                                            "t", flags),
+                                SD_BUS_RESULT("a(sss)", changes),
+                                bus_image_method_detach,
+                                SD_BUS_VTABLE_UNPRIVILEGED),
         SD_BUS_METHOD_WITH_ARGS("Reattach",
                                 SD_BUS_ARGS("as", matches,
                                             "s", profile,
@@ -748,6 +882,16 @@ const sd_bus_vtable image_vtable[] = {
                                               "a(sss)", changes_updated),
                                 bus_image_method_reattach,
                                 SD_BUS_VTABLE_UNPRIVILEGED),
+        SD_BUS_METHOD_WITH_ARGS("ReattacheWithExtensions",
+                                SD_BUS_ARGS("as", extensions,
+                                            "as", matches,
+                                            "s", profile,
+                                            "s", copy_mode,
+                                            "t", flags),
+                                SD_BUS_RESULT("a(sss)", changes_removed,
+                                              "a(sss)", changes_updated),
+                                bus_image_method_reattach,
+                                SD_BUS_VTABLE_UNPRIVILEGED),
         SD_BUS_METHOD_WITH_ARGS("Remove",
                                 SD_BUS_NO_ARGS,
                                 SD_BUS_NO_RESULT,