原始文献 / 论坛帖 / Re: Dealing with SHA-256 Collisions
Re: Dealing with SHA-256 Collisions
Bitcointalk · 2010-06-14 20:39:50 UTC
SHA-256 非常强。它不是 MD5 到 SHA1 那种小步迭代。除非出现重大的突破性攻击，它能撑几十年。
如果 SHA-256 被彻底攻破，我觉得我们可以对出事之前那条诚实的链达成共识，把它锁定，然后换新的哈希函数继续。
如果哈希是慢慢出问题的，我们可以有序过渡到新哈希。软件会设定从某个区块号开始用新哈希。大家要在那之前升级。软件可以把所有旧区块的新哈希存下来，确保没人能拿另一个有相同旧哈希的区块来顶替。
英文原文
SHA-256 is very strong. It's not like the incremental step from MD5 to SHA1. It can last several decades unless there's some massive breakthrough attack.
If SHA-256 became completely broken, I think we could come to some agreement about what the honest block chain was before the trouble started, lock that in and continue from there with a new hash function.
If the hash breakdown came gradually, we could transition to a new hash in an orderly way. The software would be programmed to start using a new hash after a certain block number. Everyone would have to upgrade by that time. The software could save the new hash of all the old blocks to make sure a different block with the same old hash can't be used.