From 2890aef9e8924a6ddc170034679b7313372b3567 Mon Sep 17 00:00:00 2001
From: William Pitcock <nenolod@dereferenced.org>
Date: Tue, 31 Jul 2018 21:41:18 +0000
Subject: [PATCH] activitypub: add digest header to outbound messages and sign
 it

---
 lib/pleroma/web/activity_pub/activity_pub.ex | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/lib/pleroma/web/activity_pub/activity_pub.ex b/lib/pleroma/web/activity_pub/activity_pub.ex
index 464832a1e..90a39ce69 100644
--- a/lib/pleroma/web/activity_pub/activity_pub.ex
+++ b/lib/pleroma/web/activity_pub/activity_pub.ex
@@ -641,8 +641,14 @@ defmodule Pleroma.Web.ActivityPub.ActivityPub do
     Logger.info("Federating #{id} to #{inbox}")
     host = URI.parse(inbox).host
 
+    digest = "SHA-256=" <> (:crypto.hash(:sha256, json) |> Base.encode64())
+
     signature =
-      Pleroma.Web.HTTPSignatures.sign(actor, %{host: host, "content-length": byte_size(json)})
+      Pleroma.Web.HTTPSignatures.sign(actor, %{
+        host: host,
+        "content-length": byte_size(json),
+        digest: digest
+      })
 
     @httpoison.post(
       inbox,