From 8baaf366c4dbfc071bc53ac4728b9c1e8dc11a21 Mon Sep 17 00:00:00 2001
From: Jason Volk <jason@zemos.net>
Date: Sun, 23 Feb 2020 22:44:14 -0800
Subject: [PATCH] ircd::m::event: Fix signature interface regression; optimize
 call path.

---
 include/ircd/m/event/event.h  |  2 ++
 matrix/event.cc               | 55 +++++++++++++++++++++++++----------
 modules/federation/invite.cc  |  6 +++-
 modules/federation/invite2.cc |  2 +-
 4 files changed, 48 insertions(+), 17 deletions(-)

diff --git a/include/ircd/m/event/event.h b/include/ircd/m/event/event.h
index b8db1af53..c2915ba05 100644
--- a/include/ircd/m/event/event.h
+++ b/include/ircd/m/event/event.h
@@ -43,6 +43,7 @@ namespace ircd::m
 	id::event make_id(const event &, const string_view &version, id::event::buf &buf);
 
 	json::object hashes(const mutable_buffer &, const event &);
+	event signatures(const mutable_buffer &, const m::event &, const string_view &origin);
 	event signatures(const mutable_buffer &, const m::event &);
 	event essential(event, const mutable_buffer &content);
 
@@ -58,6 +59,7 @@ namespace ircd::m
 
 	sha256::buf hash(const event &);
 	ed25519::sig sign(const event &, const ed25519::sk &);
+	ed25519::sig sign(const event &, const string_view &origin);
 	ed25519::sig sign(const event &);
 }
 
diff --git a/matrix/event.cc b/matrix/event.cc
index fadf86270..728c6a0d1 100644
--- a/matrix/event.cc
+++ b/matrix/event.cc
@@ -211,9 +211,22 @@ ircd::m::event::signatures(const mutable_buffer &out,
 	return json::stringify(mutable_buffer{out}, sigs);
 }
 
+ircd::m::event
+ircd::m::signatures(const mutable_buffer &out,
+                    const m::event &event)
+{
+	const string_view &origin
+	{
+		at<"origin"_>(event)
+	};
+
+	return signatures(out, event, origin);
+}
+
 ircd::m::event
 ircd::m::signatures(const mutable_buffer &out_,
-                    const m::event &event_)
+                    const m::event &event_,
+                    const string_view &origin)
 {
 	thread_local char content[event::MAX_SIZE];
 	m::event event
@@ -222,19 +235,14 @@ ircd::m::signatures(const mutable_buffer &out_,
 	};
 
 	thread_local char buf[event::MAX_SIZE];
-	const json::object &preimage
+	const string_view &preimage
 	{
 		stringify(buf, event)
 	};
 
-	const ed25519::sig sig
+	const auto &secret_key
 	{
-		sign(preimage)
-	};
-
-	const auto &origin
-	{
-		json::at<"origin"_>(event)
+		m::secret_key(my(origin))
 	};
 
 	const string_view public_key_id
@@ -242,12 +250,22 @@ ircd::m::signatures(const mutable_buffer &out_,
 		m::public_key_id(my(origin))
 	};
 
-	thread_local char sigb64buf[b64encode_size(sizeof(sig))];
-	const json::member my_sig
+	const ed25519::sig my_sig
+	{
+		event::sign(preimage, secret_key)
+	};
+
+	static const auto sigb64bufsz
+	{
+		b64encode_size(sizeof(my_sig))
+	};
+
+	thread_local char sigb64buf[sigb64bufsz];
+	const json::member my_sig_member
 	{
 		origin, json::members
 		{
-			{ public_key_id, b64encode_unpadded(sigb64buf, sig) }
+			{ public_key_id, b64encode_unpadded(sigb64buf, my_sig) }
 		}
 	};
 
@@ -255,9 +273,9 @@ ircd::m::signatures(const mutable_buffer &out_,
 	thread_local std::array<json::member, SIG_MAX> sigs;
 
 	size_t i(0);
-	sigs.at(i++) = my_sig;
+	sigs.at(i++) = my_sig_member;
 	for(const auto &[host, sig] : json::get<"signatures"_>(event_))
-		if(!my_host(json::string(host)))
+		if(json::string(host) != origin)
 			sigs.at(i++) = { host, sig };
 
 	event = event_;
@@ -303,9 +321,16 @@ ircd::m::sign(const event &event)
 {
 	const string_view &origin
 	{
-		json::at<"origin"_>(event)
+		at<"origin"_>(event)
 	};
 
+	return sign(event, origin);
+}
+
+ircd::ed25519::sig
+ircd::m::sign(const event &event,
+              const string_view &origin)
+{
 	const auto &secret_key
 	{
 		m::secret_key(my(origin))
diff --git a/modules/federation/invite.cc b/modules/federation/invite.cc
index 69d7bd02d..a4386b0cd 100644
--- a/modules/federation/invite.cc
+++ b/modules/federation/invite.cc
@@ -110,11 +110,15 @@ put__invite(client &client,
 		};
 
 	check_event(request, event);
+	const m::user::id target
+	{
+		at<"state_key"_>(event)
+	};
 
 	thread_local char sigs[4_KiB];
 	const m::event signed_event
 	{
-		signatures(sigs, event)
+		signatures(sigs, event, target.host())
 	};
 
 	const json::strung revent
diff --git a/modules/federation/invite2.cc b/modules/federation/invite2.cc
index 5735338a8..f2974afaf 100644
--- a/modules/federation/invite2.cc
+++ b/modules/federation/invite2.cc
@@ -184,7 +184,7 @@ put__invite(client &client,
 	thread_local char sigs[4_KiB];
 	m::event signed_event
 	{
-		signatures(sigs, event)
+		signatures(sigs, event, target.host())
 	};
 
 	signed_event.event_id = event_id;