diff --git a/interface/include/mbedtls/base64.h b/interface/include/mbedtls/base64.h
new file mode 100644
index 0000000..8f459b7
--- /dev/null
+++ b/interface/include/mbedtls/base64.h
@@ -0,0 +1,82 @@
+/**
+ * \file base64.h
+ *
+ * \brief RFC 1521 base64 encoding/decoding
+ */
+/*
+ *  Copyright The Mbed TLS Contributors
+ *  SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
+ */
+#ifndef MBEDTLS_BASE64_H
+#define MBEDTLS_BASE64_H
+
+#include "mbedtls/build_info.h"
+
+#include <stddef.h>
+
+/** Output buffer too small. */
+#define MBEDTLS_ERR_BASE64_BUFFER_TOO_SMALL               -0x002A
+/** Invalid character in input. */
+#define MBEDTLS_ERR_BASE64_INVALID_CHARACTER              -0x002C
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * \brief          Encode a buffer into base64 format
+ *
+ * \param dst      destination buffer
+ * \param dlen     size of the destination buffer
+ * \param olen     number of bytes written
+ * \param src      source buffer
+ * \param slen     amount of data to be encoded
+ *
+ * \return         0 if successful, or MBEDTLS_ERR_BASE64_BUFFER_TOO_SMALL.
+ *                 *olen is always updated to reflect the amount
+ *                 of data that has (or would have) been written.
+ *                 If that length cannot be represented, then no data is
+ *                 written to the buffer and *olen is set to the maximum
+ *                 length representable as a size_t.
+ *
+ * \note           Call this function with dlen = 0 to obtain the
+ *                 required buffer size in *olen
+ */
+int mbedtls_base64_encode(unsigned char *dst, size_t dlen, size_t *olen,
+                          const unsigned char *src, size_t slen);
+
+/**
+ * \brief          Decode a base64-formatted buffer
+ *
+ * \param dst      destination buffer (can be NULL for checking size)
+ * \param dlen     size of the destination buffer
+ * \param olen     number of bytes written
+ * \param src      source buffer
+ * \param slen     amount of data to be decoded
+ *
+ * \return         0 if successful, MBEDTLS_ERR_BASE64_BUFFER_TOO_SMALL, or
+ *                 MBEDTLS_ERR_BASE64_INVALID_CHARACTER if the input data is
+ *                 not correct. *olen is always updated to reflect the amount
+ *                 of data that has (or would have) been written.
+ *
+ * \note           Call this function with *dst = NULL or dlen = 0 to obtain
+ *                 the required buffer size in *olen
+ */
+int mbedtls_base64_decode(unsigned char *dst, size_t dlen, size_t *olen,
+                          const unsigned char *src, size_t slen);
+
+#if defined(MBEDTLS_SELF_TEST)
+/**
+ * \brief          Checkup routine
+ *
+ * \return         0 if successful, or 1 if the test failed
+ */
+int mbedtls_base64_self_test(int verbose);
+
+#endif /* MBEDTLS_SELF_TEST */
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* base64.h */