bin/static-delta: Add command to verify delta signature

Add new "static-delta verify" sub-command.
This supports multiple keys to verify the static-delta file.

Signed-off-by: Frédéric Danis <frederic.danis@collabora.com>

src/ostree/ot-builtin-static-delta.c

@@ -43,6 +43,7 @@ static gboolean opt_if_not_exists;
 static char **opt_key_ids;
 static char *opt_sign_name;
 static char *opt_keysfilename;
+static char *opt_keysdir;
 
 #define BUILTINPROTO(name) static gboolean ot_static_delta_builtin_ ## name (int argc, char **argv, OstreeCommandInvocation *invocation, GCancellable *cancellable, GError **error)
 
@@ -51,6 +52,7 @@ BUILTINPROTO(show);
 BUILTINPROTO(delete);
 BUILTINPROTO(generate);
 BUILTINPROTO(apply_offline);
+BUILTINPROTO(verify);
 
 #undef BUILTINPROTO
 
@@ -70,6 +72,9 @@ static OstreeCommand static_delta_subcommands[] = {
   { "apply-offline", OSTREE_BUILTIN_FLAG_NONE,
     ot_static_delta_builtin_apply_offline,
     "Apply static delta file" },
+  { "verify", OSTREE_BUILTIN_FLAG_NONE,
+    ot_static_delta_builtin_verify,
+    "Verify static delta signatures" },
   { NULL, 0, NULL, NULL }
 };
 
@@ -107,6 +112,15 @@ static GOptionEntry list_options[] = {
   { NULL }
 };
 
+static GOptionEntry verify_options[] = {
+  { "sign-type", 0, 0, G_OPTION_ARG_STRING, &opt_sign_name, "Signature type to use (defaults to 'ed25519')", "NAME"},
+#if defined(HAVE_LIBSODIUM)
+  { "keys-file", 0, 0, G_OPTION_ARG_STRING, &opt_keysfilename, "Read key(s) from file", "NAME"},
+  { "keys-dir", 0, 0, G_OPTION_ARG_STRING, &opt_keysdir, "Redefine system-wide directories with public and revoked keys for verification", "NAME"},
+#endif
+  { NULL }
+};
+
 static void
 static_delta_usage (char    **argv,
                     gboolean  is_error)
@@ -439,6 +453,68 @@ ot_static_delta_builtin_apply_offline (int argc, char **argv, OstreeCommandInvoc
   return TRUE;
 }
 
+static gboolean
+ot_static_delta_builtin_verify (int argc, char **argv, OstreeCommandInvocation *invocation, GCancellable *cancellable, GError **error)
+{
+  g_autoptr (GOptionContext) context = g_option_context_new ("STATIC-DELTA-FILE [KEY-ID...]");
+  g_autoptr (OstreeRepo) repo = NULL;
+  gboolean verified;
+  char **key_ids;
+  int n_key_ids;
+
+  if (!ostree_option_context_parse (context, verify_options, &argc, &argv, invocation, &repo, cancellable, error))
+    return FALSE;
+
+  if (argc < 3)
+    {
+      g_set_error_literal (error, G_IO_ERROR, G_IO_ERROR_FAILED,
+                           "DELTA must be specified");
+      return FALSE;
+    }
+
+  opt_sign_name = opt_sign_name ?: OSTREE_SIGN_NAME_ED25519;
+
+  const char *delta_id = argv[2];
+
+  g_autoptr (OstreeSign) sign = ostree_sign_get_by_name (opt_sign_name, error);
+  if (!sign)
+    {
+      g_print("Sign-type not supported\n");
+      return FALSE;
+    }
+
+  key_ids = argv + 3;
+  n_key_ids = argc - 3;
+  for (int i = 0; i < n_key_ids; i++)
+    {
+      g_autoptr (GVariant) pk = g_variant_new_string(key_ids[i]);
+      if (!ostree_sign_add_pk(sign, pk, error))
+        return FALSE;
+    }
+  if ((n_key_ids == 0) || opt_keysfilename)
+    {
+      g_autoptr (GVariantBuilder) builder = NULL;
+      g_autoptr (GVariant) options = NULL;
+
+      builder = g_variant_builder_new (G_VARIANT_TYPE ("a{sv}"));
+      /* Use custom directory with public and revoked keys instead of system-wide directories */
+      if (opt_keysdir)
+        g_variant_builder_add (builder, "{sv}", "basedir", g_variant_new_string (opt_keysdir));
+      /* The last chance for verification source -- system files */
+      if (opt_keysfilename)
+        g_variant_builder_add (builder, "{sv}", "filename", g_variant_new_string (opt_keysfilename));
+      options = g_variant_builder_end (builder);
+
+      if (!ostree_sign_load_pk (sign, options, error))
+        return FALSE;
+    }
+
+  verified = ostree_repo_static_delta_verify_signature (repo, delta_id, sign, NULL, error);
+  g_print ("Verification %s\n", verified ? "OK" : "fails");
+
+  return verified;
+}
+
 gboolean
 ostree_builtin_static_delta (int argc, char **argv, OstreeCommandInvocation *invocation, GCancellable *cancellable, GError **error)
 {