The yellow paper (see section 4.4) defines an extraData
header field as follows:
An arbitrary byte array containing data relevant to this block. This must be 32 bytes or fewer
Can contracts natively read this extraData
?
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Sign up to join this communityNo, they cannot. However, it is quite simple to trustlesly verify the extraData from the past 256 blocks: simply provide the full header and make sure the hash matches the block hash
eth_getBlock
RPC call. Only the past 256 block headers are directly accessible to contracts
Apr 12, 2017 at 13:28