From 029df5d3292bad193a41c52e36c922fe48aeaa1e Mon Sep 17 00:00:00 2001
From: gmbnt <andriesseniels@gmail.com>
Date: Thu, 2 Apr 2020 12:20:14 +1100
Subject: [PATCH] Guard against invalid path sizes

---
 .../src/Loki/API/Onion Requests/OnionRequestAPI.swift            | 1 +
 1 file changed, 1 insertion(+)

diff --git a/SignalServiceKit/src/Loki/API/Onion Requests/OnionRequestAPI.swift b/SignalServiceKit/src/Loki/API/Onion Requests/OnionRequestAPI.swift
index 1acf0ef20..63daf0a4b 100644
--- a/SignalServiceKit/src/Loki/API/Onion Requests/OnionRequestAPI.swift	
+++ b/SignalServiceKit/src/Loki/API/Onion Requests/OnionRequestAPI.swift	
@@ -191,6 +191,7 @@ internal enum OnionRequestAPI {
 
     /// Returns a `Path` to be used for building an onion request. Builds new paths as needed.
     private static func getPath() -> Promise<Path> {
+        guard pathSize >= 1 else { preconditionFailure("Cannot build path of size zero.") }
         // randomElement() uses the system's default random generator, which is cryptographically secure
         if paths.count >= pathCount {
             return Promise<Path> { $0.fulfill(paths.randomElement()!) }