Author: Russell O'Connor 2017-09-13 13:24:14
Published on: 2017-09-13T13:24:14+00:00
Mark Friedenbach, a member of the bitcoin-dev community, stated in an email that 4MB of secp256k1 signatures takes approximately 10 seconds to validate on his 5-year-old laptop. This is based on 125,000 signatures and ignoring public keys and other factors that consume space. He also stated that this is much less than bad blocks that can be constructed using other vulnerabilities. In response, another member of the community commented that if there were no sigops limits, the worst-case block could have closer to 1,000,000 CHECKSIG operations. However, signature checks are cached, so repeating the sequence "2DUP CHECKSIGVERIFY" does not create as many checksig operations as expected. To defeat the cache, one can repeat the sequence "2DUP CHECKSIG DROP CODESEPARATOR", which will create unique signature validation requests every 4 bytes.
Updated on: 2023-05-20T03:54:12.507462+00:00