Isn't that a little like the guy who committed suicide, cut himself up in little pieces, and flushed himself down the toilet?
Some checksums are computed such that the checksum is part of the message, and if all if well, the checksum of the entire message including the appended sum is 0 or 0xffff or some such, but the original checksum I think is always computed on what came before it. The bi-sync CRC-16 (boy, am I dating myself!) was computed that way IIRC. Charles -----Original Message----- From: owner-openssl-us...@openssl.org [mailto:owner-openssl-us...@openssl.org] On Behalf Of Michael Zintakis Sent: Saturday, October 27, 2012 9:31 AM To: openssl-users@openssl.org Subject: add hash signature as part of the stream on which this hash is based on Maybe a bit daft of me to ask this, but is it possible to calculate a hash on a stream of bytes where the resulting hash is considered to be part of that stream? In other words, lets assume that I have a stream which is, say, 64 bytes long in total, consisting of 48 bytes of "payload", plus 16-byte for the hash and that hash has been calculated based on the *entire* stream (payload+hash) of 64 bytes. Would that be possible to produce with openssl or is this a bit of a chicken-and-egg scenario? Thanks! ______________________________________________________________________ OpenSSL Project http://www.openssl.org User Support Mailing List openssl-users@openssl.org Automated List Manager majord...@openssl.org ______________________________________________________________________ OpenSSL Project http://www.openssl.org User Support Mailing List openssl-users@openssl.org Automated List Manager majord...@openssl.org
