Re: [TLS] Query regarding generating client_write_key.
Simon Josefsson <simon@josefsson.org> Tue, 27 September 2011 14:02 UTC
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From: Simon Josefsson <simon@josefsson.org>
To: nilesh <nilesh.tayade@netscout.com>
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Date: Tue, 27 Sep 2011 16:05:21 +0200
In-Reply-To: <4E818EF3.4090206@netscout.com> (nilesh's message of "Tue, 27 Sep 2011 14:23:07 +0530")
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Cc: tls@ietf.org
Subject: Re: [TLS] Query regarding generating client_write_key.
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nilesh <nilesh.tayade@netscout.com> writes: > Hi, > > I am new to the TLS/Cryptography and started working on decrypting the > packets over SSL/TLS. > I have followed the RFC2246, 5246. ... > Queries: > 1. The md5 generates 16bytes and SHA1 generates 20bytes so xor will be > 20bytes. > But the key we expect should be 32bytes (iterated the MD5/SHA1 twice > for that). How could this be achieved? > 2. Any suggestions on if the PRF() is designed somewhere? Pointers on > how it could be designed? > > I tried several ways, but getting the wrong key. Could someone please > advice? Did you read section 5 of RFC 5246? It explains how the PRF function works. /Simon
- [TLS] Query regarding generating client_write_key. nilesh
- Re: [TLS] Query regarding generating client_write… Simon Josefsson
- Re: [TLS] Query regarding generating client_write… Joshua Davies
- Re: [TLS] Query regarding generating client_write… Joshua Davies
- Re: [TLS] Query regarding generating client_write… nilesh