sign: Factor out logic to read key blobs

This defines a new interface OstreeBlobReader, which encapsulates the
key file parsing logic. This would make it easy to support custom file
formats such as PEM.

Signed-off-by: Daiki Ueno <[email protected]>

Makefile-libostree-defines.am

@@ -48,6 +48,7 @@ libostree_public_headers = \
 	src/libostree/ostree-kernel-args.h \
 	src/libostree/ostree-sign.h \
 	src/libostree/ostree-sign-ed25519.h \
+	src/libostree/ostree-blob-reader.h \
 	$(NULL)
 
 # This one is generated via configure.ac, and the gtk-doc

Makefile-libostree.am

@@ -175,9 +175,9 @@ endif # USE_GPGME
 symbol_files = $(top_srcdir)/src/libostree/libostree-released.sym
 
 # Uncomment this include when adding new development symbols.
-#if BUILDOPT_IS_DEVEL_BUILD
-#symbol_files += $(top_srcdir)/src/libostree/libostree-devel.sym
-#endif
+if BUILDOPT_IS_DEVEL_BUILD
+symbol_files += $(top_srcdir)/src/libostree/libostree-devel.sym
+endif
 
 # http://blog.jgc.org/2007/06/escaping-comma-and-space-in-gnu-make.html
 wl_versionscript_arg = -Wl,--version-script=
@@ -262,6 +262,12 @@ libostree_1_la_SOURCES += \
 	src/libostree/ostree-sign-ed25519.c \
 	src/libostree/ostree-sign-ed25519.h \
 	src/libostree/ostree-sign-private.h \
+	src/libostree/ostree-blob-reader.c \
+	src/libostree/ostree-blob-reader.h \
+	src/libostree/ostree-blob-reader-base64.c \
+	src/libostree/ostree-blob-reader-base64.h \
+	src/libostree/ostree-blob-reader-raw.c \
+	src/libostree/ostree-blob-reader-raw.h \
 	$(NULL)
 
 if USE_COMPOSEFS

apidoc/ostree-sections.txt

@@ -767,6 +767,15 @@ ostree_sign_metadata_key
 ostree_sign_set_pk
 ostree_sign_set_sk
 ostree_sign_summary
+ostree_sign_read_pk
+ostree_sign_read_sk
 <SUBSECTION Standard>
 ostree_sign_get_type
 </SECTION>
+
+<SECTION>
+<FILE>ostree-blob-reader</FILE>
+ostree_blob_reader_read_blob
+<SUBSECTION Standard>
+ostree_blob_reader_get_type
+</SECTION>

src/libostree/libostree-devel.sym

@@ -20,6 +20,14 @@
    - uncomment the include in Makefile-libostree.am
 */
 
+LIBOSTREE_2024.8 {
+global:
+  ostree_sign_read_pk;
+  ostree_sign_read_sk;
+  ostree_blob_reader_get_type;
+  ostree_blob_reader_read_blob;
+} LIBOSTREE_2024.7;
+
 /* Stub section for the stable release *after* this development one; don't
  * edit this other than to update the year.  This is just a copy/paste
  * source.  Replace $LASTSTABLE with the last stable version, and $NEWVERSION

src/libostree/ostree-blob-reader-base64.c

@@ -0,0 +1,80 @@
+/*
+ * Copyright (C) 2024 Red Hat, Inc.
+ *
+ * SPDX-License-Identifier: LGPL-2.0+
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#include "config.h"
+
+#include "ostree-blob-reader-base64.h"
+
+struct _OstreeBlobReaderBase64
+{
+  GDataInputStream parent_instance;
+};
+
+static void ostree_blob_reader_base64_iface_init (OstreeBlobReaderInterface *iface);
+
+G_DEFINE_TYPE_WITH_CODE (OstreeBlobReaderBase64, _ostree_blob_reader_base64,
+                         G_TYPE_DATA_INPUT_STREAM,
+                         G_IMPLEMENT_INTERFACE (OSTREE_TYPE_BLOB_READER,
+                                                ostree_blob_reader_base64_iface_init));
+
+static void
+ostree_blob_reader_base64_iface_init (OstreeBlobReaderInterface *iface)
+{
+  iface->read_blob = ostree_blob_reader_base64_read_blob;
+}
+
+static void
+_ostree_blob_reader_base64_class_init (OstreeBlobReaderBase64Class *klass)
+{
+}
+
+static void
+_ostree_blob_reader_base64_init (OstreeBlobReaderBase64 *self)
+{
+}
+
+OstreeBlobReaderBase64 *
+_ostree_blob_reader_base64_new (GInputStream *stream)
+{
+  return g_object_new (OSTREE_TYPE_BLOB_READER_BASE64, "base-stream", stream, NULL);
+}
+
+GBytes *
+ostree_blob_reader_base64_read_blob (OstreeBlobReader *self, GCancellable *cancellable,
+                                     GError **error)
+{
+  gsize len = 0;
+  g_autoptr (GError) local_error = NULL;
+  g_autofree char *line
+      = g_data_input_stream_read_line (G_DATA_INPUT_STREAM (self), &len, cancellable, &local_error);
+  if (local_error != NULL)
+    {
+      g_propagate_error (error, g_steal_pointer (&local_error));
+      return NULL;
+    }
+
+  if (line == NULL)
+    return NULL;
+
+  gsize n_elements;
+  g_base64_decode_inplace (line, &n_elements);
+  explicit_bzero (line + n_elements, len - n_elements);
+
+  return g_bytes_new_take (g_steal_pointer (&line), n_elements);
+}

src/libostree/ostree-blob-reader-base64.h

@@ -0,0 +1,39 @@
+/*
+ * Copyright (C) 2024 Red Hat, Inc.
+ *
+ * SPDX-License-Identifier: LGPL-2.0+
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+#include "ostree-blob-reader.h"
+
+G_BEGIN_DECLS
+
+#define OSTREE_TYPE_BLOB_READER_BASE64 (_ostree_blob_reader_base64_get_type ())
+
+_OSTREE_PUBLIC
+G_DECLARE_FINAL_TYPE (OstreeBlobReaderBase64, _ostree_blob_reader_base64, OSTREE,
+                      BLOB_READER_BASE64, GDataInputStream);
+
+_OSTREE_PUBLIC
+OstreeBlobReaderBase64 *_ostree_blob_reader_base64_new (GInputStream *stream);
+
+_OSTREE_PUBLIC
+GBytes *ostree_blob_reader_base64_read_blob (OstreeBlobReader *self, GCancellable *cancellable,
+                                             GError **error);
+
+G_END_DECLS

src/libostree/ostree-blob-reader-raw.c

@@ -0,0 +1,74 @@
+/*
+ * Copyright (C) 2024 Red Hat, Inc.
+ *
+ * SPDX-License-Identifier: LGPL-2.0+
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#include "config.h"
+
+#include "ostree-blob-reader-raw.h"
+
+struct _OstreeBlobReaderRaw
+{
+  GDataInputStream parent_instance;
+};
+
+static void ostree_blob_reader_raw_iface_init (OstreeBlobReaderInterface *iface);
+
+G_DEFINE_TYPE_WITH_CODE (OstreeBlobReaderRaw, _ostree_blob_reader_raw, G_TYPE_DATA_INPUT_STREAM,
+                         G_IMPLEMENT_INTERFACE (OSTREE_TYPE_BLOB_READER,
+                                                ostree_blob_reader_raw_iface_init));
+
+static void
+ostree_blob_reader_raw_iface_init (OstreeBlobReaderInterface *iface)
+{
+  iface->read_blob = ostree_blob_reader_raw_read_blob;
+}
+
+static void
+_ostree_blob_reader_raw_class_init (OstreeBlobReaderRawClass *klass)
+{
+}
+
+static void
+_ostree_blob_reader_raw_init (OstreeBlobReaderRaw *self)
+{
+}
+
+OstreeBlobReaderRaw *
+_ostree_blob_reader_raw_new (GInputStream *stream)
+{
+  return g_object_new (OSTREE_TYPE_BLOB_READER_RAW, "base-stream", stream, NULL);
+}
+
+GBytes *
+ostree_blob_reader_raw_read_blob (OstreeBlobReader *self, GCancellable *cancellable, GError **error)
+{
+  gsize len = 0;
+  g_autoptr (GError) local_error = NULL;
+  g_autofree char *line
+      = g_data_input_stream_read_line (G_DATA_INPUT_STREAM (self), &len, cancellable, &local_error);
+  if (local_error != NULL)
+    {
+      g_propagate_error (error, g_steal_pointer (&local_error));
+      return NULL;
+    }
+
+  if (line == NULL)
+    return NULL;
+
+  return g_bytes_new_take (g_steal_pointer (&line), len);
+}

src/libostree/ostree-blob-reader-raw.h

@@ -0,0 +1,39 @@
+/*
+ * Copyright (C) 2024 Red Hat, Inc.
+ *
+ * SPDX-License-Identifier: LGPL-2.0+
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+#include "ostree-blob-reader.h"
+
+G_BEGIN_DECLS
+
+#define OSTREE_TYPE_BLOB_READER_RAW (_ostree_blob_reader_raw_get_type ())
+
+_OSTREE_PUBLIC
+G_DECLARE_FINAL_TYPE (OstreeBlobReaderRaw, _ostree_blob_reader_raw, OSTREE, BLOB_READER_RAW,
+                      GDataInputStream);
+
+_OSTREE_PUBLIC
+OstreeBlobReaderRaw *_ostree_blob_reader_raw_new (GInputStream *stream);
+
+_OSTREE_PUBLIC
+GBytes *ostree_blob_reader_raw_read_blob (OstreeBlobReader *self, GCancellable *cancellable,
+                                          GError **error);
+
+G_END_DECLS

src/libostree/ostree-blob-reader.c

@@ -0,0 +1,37 @@
+/*
+ * Copyright (C) 2024 Red Hat, Inc.
+ *
+ * SPDX-License-Identifier: LGPL-2.0+
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#include "config.h"
+
+#include "ostree-blob-reader.h"
+
+G_DEFINE_INTERFACE (OstreeBlobReader, ostree_blob_reader, G_TYPE_OBJECT);
+
+static void
+ostree_blob_reader_default_init (OstreeBlobReaderInterface *iface)
+{
+  g_debug ("OstreeBlobReader initialization");
+}
+
+GBytes *
+ostree_blob_reader_read_blob (OstreeBlobReader *self, GCancellable *cancellable, GError **error)
+{
+  g_assert (OSTREE_IS_BLOB_READER (self));
+  return OSTREE_BLOB_READER_GET_IFACE (self)->read_blob (self, cancellable, error);
+}

src/libostree/ostree-blob-reader.h

@@ -0,0 +1,42 @@
+/*
+ * Copyright (C) 2024 Red Hat, Inc.
+ *
+ * SPDX-License-Identifier: LGPL-2.0+
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+#include "ostree-types.h"
+#include <gio/gio.h>
+
+G_BEGIN_DECLS
+
+#define OSTREE_TYPE_BLOB_READER (ostree_blob_reader_get_type ())
+_OSTREE_PUBLIC
+G_DECLARE_INTERFACE (OstreeBlobReader, ostree_blob_reader, OSTREE, BLOB_READER, GObject)
+
+struct _OstreeBlobReaderInterface
+{
+  GTypeInterface g_iface;
+
+  GBytes *(*read_blob) (OstreeBlobReader *self, GCancellable *cancellable, GError **error);
+};
+
+_OSTREE_PUBLIC
+GBytes *ostree_blob_reader_read_blob (OstreeBlobReader *self, GCancellable *cancellable,
+                                      GError **error);
+
+G_END_DECLS