Fix use of pem_read_buffer() in PK, DHM and X509
diff --git a/include/mbedtls/pk.h b/include/mbedtls/pk.h
index 44efef0..3ed8b5e 100644
--- a/include/mbedtls/pk.h
+++ b/include/mbedtls/pk.h
@@ -427,11 +427,12 @@
#if defined(MBEDTLS_PK_PARSE_C)
/** \ingroup pk_module */
/**
- * \brief Parse a private key
+ * \brief Parse a private key in PEM or DER format
*
* \param ctx key to be initialized
* \param key input buffer
* \param keylen size of the buffer
+ * (including the terminating null byte for PEM data)
* \param pwd password for decryption (optional)
* \param pwdlen size of the password
*
@@ -449,11 +450,12 @@
/** \ingroup pk_module */
/**
- * \brief Parse a public key
+ * \brief Parse a public key in PEM or DER format
*
* \param ctx key to be initialized
* \param key input buffer
* \param keylen size of the buffer
+ * (including the terminating null byte for PEM data)
*
* \note On entry, ctx must be empty, either freshly initialised
* with mbedtls_pk_init() or reset with mbedtls_pk_free(). If you need a