From 3da03d23baa90acb119c7946c2cd740a72ba069d Mon Sep 17 00:00:00 2001
From: Andris Reinman <andris@reinman.eu>
Date: Mon, 21 Oct 2024 10:41:00 +0300
Subject: [PATCH] fix(BodyHashStream): Skip header

---
 lib/dkim/body/index.js | 51 +++++-------------------------------------
 1 file changed, 6 insertions(+), 45 deletions(-)

diff --git a/lib/dkim/body/index.js b/lib/dkim/body/index.js
index 15328ad..0234215 100644
--- a/lib/dkim/body/index.js
+++ b/lib/dkim/body/index.js
@@ -3,7 +3,6 @@
 const { SimpleHash } = require('./simple');
 const { RelaxedHash } = require('./relaxed');
 const { Transform } = require('node:stream');
-const { MessageParser } = require('../message-parser');
 
 const dkimBody = (canonicalization, ...options) => {
     canonicalization = (canonicalization || 'simple/simple').toString().split('/').pop().toLowerCase().trim();
@@ -20,50 +19,15 @@ const dkimBody = (canonicalization, ...options) => {
     }
 };
 
-class MessageHasher extends MessageParser {
-    constructor(canonicalization, ...options) {
-        super();
-        this.hasher = dkimBody(canonicalization, ...options);
-        this.bodyHash = null;
-    }
-
-    async nextChunk(chunk) {
-        this.hasher.update(chunk);
-    }
-
-    async finalChunk() {
-        this.bodyHash = this.hasher.digest('base64');
-    }
-}
-
 class BodyHashStream extends Transform {
     constructor(canonicalization, ...options) {
         super();
 
-        this.finished = false;
-        this.finishCb = null;
-
         this.byteLength = 0;
 
-        this.messageHasher = new MessageHasher(canonicalization, ...options);
-        this.bodyHash = null;
-        this.messageHasher.once('finish', () => this.finishHashing());
-        this.messageHasher.once('end', () => this.finishHashing());
-        this.messageHasher.once('error', err => this.destroy(err));
-    }
-
-    finishHashing() {
-        if (this.finished || !this.finishCb) {
-            return;
-        }
-        this.finished = true;
-        let done = this.finishCb;
-        this.finishCb = null;
-
-        this.bodyHash = this.messageHasher.bodyHash;
-        this.emit('hash', this.bodyHash);
+        this.hasher = dkimBody(canonicalization, ...options);
 
-        done();
+        this.bodyHash = null;
     }
 
     _transform(chunk, encoding, done) {
@@ -77,19 +41,16 @@ class BodyHashStream extends Transform {
 
         this.byteLength += chunk.length;
 
+        this.hasher.update(chunk);
         this.push(chunk);
 
-        if (this.messageHasher.write(chunk) === false) {
-            // wait for drain
-            return this.messageHasher.once('drain', done);
-        }
-
         done();
     }
 
     _flush(done) {
-        this.finishCb = done;
-        this.messageHasher.end();
+        this.bodyHash = this.hasher.digest('base64');
+        this.emit('hash', this.bodyHash);
+        done();
     }
 }