diff --git a/lib/auth.js b/lib/auth.js
index 1d8754d..d951e33 100644
--- a/lib/auth.js
+++ b/lib/auth.js
@@ -88,6 +88,9 @@ async function hookDataPost(stream, plugin, connection) {
                 _dkim_mod_len: result.modulusLength,
                 _dkim_canon_header: result.format.split('/').shift(),
                 _dkim_canon_body: result.format.split('/').pop(),
+                _dkim_body_size_source: result.sourceBodyLength,
+                _dkim_body_size_canon: result.canonBodyLengthTotal,
+                _dkim_body_size_limit: result.canonBodyLengthLimited && result.canonBodyLengthLimit,
                 _dkim_signing_headers: signingHeaders.join(','),
                 _dkim_signing_headers_content_type: signingHeaders.includes('content-type') ? 'yes' : 'no',
                 _content_type_count: contentTypeHeaders.length,