From 7972e176c1bf4ccbe8fb742da60852aaeb6e3976 Mon Sep 17 00:00:00 2001 From: 1HXb9KMAtwNJqz4egi6hJx08EQgJajiBTH <1HXb9KMAtwNJqz4egi6hJx08EQgJajiBTH@bitcoin.cash> Date: Wed, 11 Dec 2019 14:57:50 -0500 Subject: [PATCH] wiki commit --- protocol/blockchain/hash.md | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/protocol/blockchain/hash.md b/protocol/blockchain/hash.md index e596de6..cc68d15 100644 --- a/protocol/blockchain/hash.md +++ b/protocol/blockchain/hash.md @@ -11,7 +11,9 @@ A variety of hashing algorithms are used throughout the Bitcoin Cash protocol. - This double hash removes the possibility of a [length extension attack](https://en.wikipedia.org/wiki/Length_extension_attack) which a single SHA-256 is vulnerable to. While this is generally not a problem for Bitcoin Cash since the pre-image (the actual data of the block) is available, it trades a minor amount of inefficiency for confidence that this property of SHA-256 cannot be exploited. - Transaction Hashing - Transactions are hashed using a single application of SHA-256. This is referred to as the transaction hash and is used to uniquely identify the transaction. (NOTE: Historical transaction hashes are not universally unique two sets of two identical coinbase transactions, thus repeated hashes. Since the block height is now required to be in the coinbase transaction, this should not be possible in the future.) - - The two cases where this occurred are the transactions with the hashes D5D27987D2A3DFC724E359870C6644B40E497BDC0589A033220FE15429D88599 and E3BF3D07D4B0375638D5F1DB5255FE07BA2C4CB067CD81B84EE974B6585FB468. + - The two cases where this occurred are the following transactions which each appear in two blocks: + - D5D27987D2A3DFC724E359870C6644B40E497BDC0589A033220FE15429D88599 + - E3BF3D07D4B0375638D5F1DB5255FE07BA2C4CB067CD81B84EE974B6585FB468 ## RIPEMD-160