Hi Brian, > If so, what is it's purpose? They are ASN.1 encoded integers. The leading '0' octect ensures the value is interpreted as non-negative. See X.680.
> Do You Yahoo!? No. Jeff On Tue, Sep 22, 2009 at 9:47 PM, Brian Kuschak <bkusc...@yahoo.com> wrote: > I'm using OpenSSL to generate EC key pairs for use in an embedded > application. As such, I need to extract and use the raw key values, and I > notice that the length of the keys as displayed by OpenSSL are exactly one > byte longer than expected. I assume the first byte listed for both public > and private are not _really_ part of the key, but I'd like confirmation on > this. If so, what is it's purpose? > > Generate the key pair: > openssl ecparam -out eckey.pem -name prime192v1 -genkey > > Notice how the private key is 25 bytes (not 24), and the public key is 49 > bytes, not 48: > openssl ec -in eckey.pem -text > > Private-Key: (192 bit) > priv: > 00:d4:7a:55:e3:0d:91:26:2e:90:02:83:97:5c:3e: > 63:25:95:fe:88:28:61:4e:e7:c5 > pub: > 04:f4:85:cc:48:15:83:7c:ee:8d:53:e8:0b:fd:a7: > 40:5f:86:d8:fc:97:72:89:04:34:a4:92:e1:33:e7: > 17:1c:55:c0:39:cc:06:c1:49:5f:d3:70:8b:08:e3: > 33:83:50:ae > > I'm using OpenSSL 0.9.8k 25 Mar 2009. > > __________________________________________________ > Do You Yahoo!? > Tired of spam? Yahoo! Mail has the best spam protection around > http://mail.yahoo.com ______________________________________________________________________ OpenSSL Project http://www.openssl.org User Support Mailing List openssl-users@openssl.org Automated List Manager majord...@openssl.org
