From b55c751358fa405aab64ec6095c50763d3082f51 Mon Sep 17 00:00:00 2001
From: Niels Andriesse <andriesseniels@gmail.com>
Date: Tue, 12 Nov 2019 14:19:50 +1100
Subject: [PATCH] Fix contact sync message parsing

---
 SignalServiceKit/src/Devices/OWSChunkedOutputStream.h   | 1 +
 SignalServiceKit/src/Devices/OWSChunkedOutputStream.m   | 5 +++++
 SignalServiceKit/src/Devices/OWSContactsOutputStream.m  | 2 +-
 SignalServiceKit/src/Loki/Messaging/ContactParser.swift | 8 +++++---
 4 files changed, 12 insertions(+), 4 deletions(-)

diff --git a/SignalServiceKit/src/Devices/OWSChunkedOutputStream.h b/SignalServiceKit/src/Devices/OWSChunkedOutputStream.h
index 537a40f15..c02a79864 100644
--- a/SignalServiceKit/src/Devices/OWSChunkedOutputStream.h
+++ b/SignalServiceKit/src/Devices/OWSChunkedOutputStream.h
@@ -15,6 +15,7 @@ NS_ASSUME_NONNULL_BEGIN
 
 // Returns NO on error.
 - (BOOL)writeData:(NSData *)data;
+- (BOOL)writeUInt32:(UInt32)value;
 - (BOOL)writeVariableLengthUInt32:(UInt32)value;
 
 @end
diff --git a/SignalServiceKit/src/Devices/OWSChunkedOutputStream.m b/SignalServiceKit/src/Devices/OWSChunkedOutputStream.m
index 16b42e9ee..c10caeae0 100644
--- a/SignalServiceKit/src/Devices/OWSChunkedOutputStream.m
+++ b/SignalServiceKit/src/Devices/OWSChunkedOutputStream.m
@@ -63,6 +63,11 @@ NS_ASSUME_NONNULL_BEGIN
     return YES;
 }
 
+- (BOOL)writeUInt32:(UInt32)value {
+    NSData *data = [[NSData alloc] initWithBytes:&value length:sizeof(value)];
+    return [self writeData:data];
+}
+
 - (BOOL)writeVariableLengthUInt32:(UInt32)value
 {
     while (YES) {
diff --git a/SignalServiceKit/src/Devices/OWSContactsOutputStream.m b/SignalServiceKit/src/Devices/OWSContactsOutputStream.m
index b9a3eef2b..c4211a873 100644
--- a/SignalServiceKit/src/Devices/OWSContactsOutputStream.m
+++ b/SignalServiceKit/src/Devices/OWSContactsOutputStream.m
@@ -94,7 +94,7 @@ disappearingMessagesConfiguration:(nullable OWSDisappearingMessagesConfiguration
     }
 
     uint32_t contactDataLength = (uint32_t)contactData.length;
-    [self writeVariableLengthUInt32:contactDataLength];
+    [self writeUInt32:contactDataLength];
     [self writeData:contactData];
 
     /*
diff --git a/SignalServiceKit/src/Loki/Messaging/ContactParser.swift b/SignalServiceKit/src/Loki/Messaging/ContactParser.swift
index 106f8234c..f863491b9 100644
--- a/SignalServiceKit/src/Loki/Messaging/ContactParser.swift
+++ b/SignalServiceKit/src/Loki/Messaging/ContactParser.swift
@@ -10,11 +10,13 @@
         var index = 0
         var result: [String] = []
         while index < data.endIndex {
-            let uncheckedSize: Int? = try? data[index..<(index+1)].withUnsafeBytes { $0.pointee }
+            let uncheckedSize: UInt32? = try? data[index..<(index+4)].withUnsafeBytes { $0.pointee }
             guard let size = uncheckedSize else { break }
-            index += 1
-            let protoAsData = data[index..<(index+size)]
+            let sizeAsInt = Int(size)
+            index += 4
+            let protoAsData = data[index..<(index+sizeAsInt)]
             guard let proto = try? SSKProtoContactDetails.parseData(protoAsData) else { break }
+            index += sizeAsInt
             result.append(proto.number)
         }
         return result