ASN1: add an internal header to validate Unicode ranges

Reviewed-by: Shane Lontis <shane.lontis@oracle.com>
Reviewed-by: Paul Dale <pauli@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/14185)

1 files changed, 31 insertions, 0 deletions

diff --git a/include/internal/unicode.h b/include/internal/unicode.h
new file mode 100644
index 0000000000..3dcdcd2c89
--- /dev/null
+++ b/include/internal/unicode.h
@@ -0,0 +1,31 @@
+/*
+ * Copyright 2021 The OpenSSL Project Authors. All Rights Reserved.
+ *
+ * Licensed under the Apache License 2.0 (the "License").  You may not use
+ * this file except in compliance with the License.  You can obtain a copy
+ * in the file LICENSE in the source distribution or at
+ * https://www.openssl.org/source/license.html
+ */
+
+#ifndef OSSL_INTERNAL_UNICODE_H
+# define OSSL_INTERNAL_UNICODE_H
+# pragma once
+
+typedef enum {
+    SURROGATE_MIN = 0xd800UL,
+    SURROGATE_MAX = 0xdfffUL,
+    UNICODE_MAX = 0x10ffffUL,
+    UNICODE_LIMIT
+} UNICODE_CONSTANTS;
+
+static ossl_unused inline int is_unicode_surrogate(unsigned long value)
+{
+    return value >= SURROGATE_MIN && value <= SURROGATE_MAX;
+}
+
+static ossl_unused inline int is_unicode_valid(unsigned long value)
+{
+    return value <= UNICODE_MAX && !is_unicode_surrogate(value);
+}
+
+#endif