Project

General

Profile

Bug #4818

murmurHash3 of uint32_t is not endian safe

Added by Jeff Thompson 3 months ago. Updated 17 days ago.

Status:
New
Priority:
Normal
Assignee:
-
Target version:
-
Start date:
01/28/2019
Due date:
% Done:

0%

Estimated time:

Description

murmurHash3 of an uint32_t value computes the hash of the in-memory 4-byte buffer. If this is part of a data structure that is sent to another computer with a difference between big endian and little endian, then they won't compute the same hash.
https://github.com/named-data/PSync/blob/0cf4b600e91455ee07c38eb22876aa6b653bc14b/PSync/detail/util.cpp#L103

Maybe this should use endian::native_to_little, similar to the TLV encoder (Intel chips use little endian):
https://github.com/named-data/ndn-cxx/blob/master/ndn-cxx/encoding/encoder.cpp#L151


Related issues

Related to PSync - Task #4659: Look into using newer and better hash functionNew2018-07-09

History

#1 Updated by Jeff Thompson 3 months ago

... although it looks like the implementation of murmurHash3 itself will compute a different result on big and little endian machines.
https://github.com/named-data/PSync/blob/0cf4b600e91455ee07c38eb22876aa6b653bc14b/PSync/detail/util.cpp#L47

#2 Updated by Ashlesh Gawande 3 months ago

  • Related to Task #4659: Look into using newer and better hash function added

#3 Updated by Jeff Thompson 17 days ago

  • Description updated (diff)

Also available in: Atom PDF