From e0fd64d29af1d99bb7e09dba7b8b05391861d5ad Mon Sep 17 00:00:00 2001
From: Neil Booth <kyuupichan@gmail.com>
Date: Wed, 22 Mar 2017 07:57:15 +0900
Subject: [PATCH] Rate-limit add_peer calls randomly

Prepare 1.0.1
---
 README.rst           | 10 ++++++++++
 server/controller.py | 11 +++++++++++
 server/session.py    |  6 ++----
 server/version.py    |  2 +-
 4 files changed, 24 insertions(+), 5 deletions(-)

diff --git a/README.rst b/README.rst
index 10b97d1..3a71dd0 100644
--- a/README.rst
+++ b/README.rst
@@ -127,6 +127,16 @@ Roadmap
 ChangeLog
 =========
 
+Version 1.0.1
+-------------
+
+* Rate-limit add_peer calls in a random way
+* Fix discovery of base height in reorgs
+* Don't permit common but invalid REPORT_HOST values
+* Set reorg limit to 8000 blocks on testnet
+* dogecoin / litecoin parameter fixes (erasmospunk, pooler)
+* minor doc tweaks
+
 Version 1.0
 -----------
 
diff --git a/server/controller.py b/server/controller.py
index c0cbf6b..a8d4d43 100644
--- a/server/controller.py
+++ b/server/controller.py
@@ -9,6 +9,7 @@ import asyncio
 import json
 import os
 import ssl
+import random
 import time
 import traceback
 import warnings
@@ -47,6 +48,7 @@ class Controller(util.LoggedClass):
         self.executor = ThreadPoolExecutor()
         self.loop.set_default_executor(self.executor)
         self.start_time = time.time()
+        self.next_add_peer_time = self.start_time
         self.coin = env.coin
         self.daemon = Daemon(env.coin.daemon_urls(env.daemon_url))
         self.bp = BlockProcessor(env, self, self.daemon)
@@ -133,6 +135,15 @@ class Controller(util.LoggedClass):
     def is_deprioritized(self, session):
         return self.session_priority(session) > self.BANDS
 
+    def permit_add_peer(self):
+        '''To prevent lots of add_peer requests filling up the peer
+        table, accept only one per random time interval.'''
+        now = time.time()
+        if now < self.next_add_peer_time:
+            return False
+        self.next_add_peer_time = now + random.randrange(0, 1800)
+        return True
+
     async def run_in_executor(self, func, *args):
         '''Wait whilst running func in the executor.'''
         return await self.loop.run_in_executor(None, func, *args)
diff --git a/server/session.py b/server/session.py
index ee0466f..6ae9d66 100644
--- a/server/session.py
+++ b/server/session.py
@@ -45,7 +45,6 @@ class SessionBase(JSONSession):
         self.bw_time = self.start_time
         self.bw_interval = 3600
         self.bw_used = 0
-        self.peer_added = False
 
     def close_connection(self):
         '''Call this to close the connection.'''
@@ -196,13 +195,12 @@ class ElectrumX(SessionBase):
 
     def add_peer(self, features):
         '''Add a peer.'''
-        if self.peer_added:
+        if not self.controller.permit_add_peer():
             return False
         peer_mgr = self.controller.peer_mgr
         peer_info = self.peer_info()
         source = peer_info[0] if peer_info else 'unknown'
-        self.peer_added = peer_mgr.on_add_peer(features, source)
-        return self.peer_added
+        return peer_mgr.on_add_peer(features, source)
 
     def peers_subscribe(self):
         '''Return the server peers as a list of (ip, host, details) tuples.'''
diff --git a/server/version.py b/server/version.py
index 334e721..e9146f2 100644
--- a/server/version.py
+++ b/server/version.py
@@ -1,5 +1,5 @@
 # Server name and protocol versions
 
-VERSION = 'ElectrumX 1.0'
+VERSION = 'ElectrumX 1.0.1'
 PROTOCOL_MIN = '1.0'
 PROTOCOL_MAX = '1.0'