1 files changed, 38 insertions, 0 deletions
diff --git a/tests/include/test/asn1_helpers.h b/tests/include/test/asn1_helpers.h
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+++ b/tests/include/test/asn1_helpers.h
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+/** Helper functions for tests that manipulate ASN.1 data.
+ */
+/*
+ *  Copyright The Mbed TLS Contributors
+ *  SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
+ */
+
+#ifndef ASN1_HELPERS_H
+#define ASN1_HELPERS_H
+
+#include "test/helpers.h"
+
+/** Skip past an INTEGER in an ASN.1 buffer.
+ *
+ * Mark the current test case as failed in any of the following conditions:
+ * - The buffer does not start with an ASN.1 INTEGER.
+ * - The integer's size or parity does not match the constraints expressed
+ *   through \p min_bits, \p max_bits and \p must_be_odd.
+ *
+ * \param p             Upon entry, `*p` points to the first byte of the
+ *                      buffer to parse.
+ *                      On successful return, `*p` points to the first byte
+ *                      after the parsed INTEGER.
+ *                      On failure, `*p` is unspecified.
+ * \param end           The end of the ASN.1 buffer.
+ * \param min_bits      Fail the test case if the integer does not have at
+ *                      least this many significant bits.
+ * \param max_bits      Fail the test case if the integer has more than
+ *                      this many significant bits.
+ * \param must_be_odd   Fail the test case if the integer is even.
+ *
+ * \return              \c 0 if the test failed, otherwise 1.
+ */
+int mbedtls_test_asn1_skip_integer(unsigned char **p, const unsigned char *end,
+                                   size_t min_bits, size_t max_bits,
+                                   int must_be_odd);
+
+#endif /* ASN1_HELPERS_H */