diff --git a/include/mbedtls/aead_chacha20_poly1305.h b/include/mbedtls/aead_chacha20_poly1305.h
index 6f7ab6f..21c3158 100644
--- a/include/mbedtls/aead_chacha20_poly1305.h
+++ b/include/mbedtls/aead_chacha20_poly1305.h
@@ -32,6 +32,10 @@
 #define MBEDTLS_ERR_AEAD_CHACHA20_POLY1305_BAD_INPUT_DATA -0x00047 /**< Invalid input parameter(s). */
 #define MBEDTLS_ERR_AEAD_CHACHA20_POLY1305_BAD_STATE      -0x00049 /**< The requested operation is not permitted in the current state */
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 typedef enum
 {
     MBEDTLS_AEAD_CHACHA20_POLY1305_ENCRYPT,
@@ -227,4 +231,8 @@
  */
 int mbedtls_aead_chacha20_poly1305_self_test( int verbose );
 
+#ifdef __cplusplus
+}
+#endif
+
 #endif /* MBEDTLS_AEAD_CHACHA20_POLY1305_H */
diff --git a/include/mbedtls/chacha20.h b/include/mbedtls/chacha20.h
index a2856a7..f88bd28 100644
--- a/include/mbedtls/chacha20.h
+++ b/include/mbedtls/chacha20.h
@@ -36,6 +36,10 @@
 
 #define MBEDTLS_ERR_CHACHA20_BAD_INPUT_DATA -0x003B /**< Invalid input parameter(s). */
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 #if !defined(MBEDTLS_CHACHA20_ALT)
 
 typedef struct
@@ -189,4 +193,8 @@
  */
 int mbedtls_chacha20_self_test( int verbose );
 
+#ifdef __cplusplus
+}
+#endif
+
 #endif /* MBEDTLS_CHACHA20_H */
diff --git a/include/mbedtls/poly1305.h b/include/mbedtls/poly1305.h
index 915f8ab..c911b9f 100644
--- a/include/mbedtls/poly1305.h
+++ b/include/mbedtls/poly1305.h
@@ -34,6 +34,10 @@
 
 #define MBEDTLS_ERR_POLY1305_BAD_INPUT_DATA -0x0041 /**< Invalid input parameter(s). */
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 #if !defined(MBEDTLS_POLY1305_ALT)
 
 typedef struct
@@ -140,4 +144,8 @@
  */
 int mbedtls_poly1305_self_test( int verbose );
 
+#ifdef __cplusplus
+}
+#endif
+
 #endif /* MBEDTLS_POLY1305_H */