[4895] in Kerberos
Re: Proposal for a SmartCard-Kerberos Implementation
daemon@ATHENA.MIT.EDU (John Hascall)
Fri Mar 31 08:13:20 1995
To: kerberos@MIT.EDU
Date: 31 Mar 1995 12:51:03 GMT
From: john@iastate.edu (John Hascall)
Kenneth D. Renard <kdrenard@arl.mil> wrote:
}Unfortunately, this opens the vulnerability of the Sandia algorithm that I
}was trying to avoid. A sniffer could capture the SecurID code via the
}unencrypted telnet and sniff the AS_REP and decrypt the TGT.
Nope. Note that there are *2* SecureID codes used.
John
}john@iastate.edu (John Hascall) writes:
}>Kenneth D. Renard <kdrenard@arl.mil> wrote:
}>}Below is a proposal for a SmartCard-Kerberos implementation. ...
}>} 1. Send SecurID code to kinit process.
}>} 2. Kinit sends request to KDC with plaintext SecurID code.
}>} 3. KDC verifies SecurID code and generates TGT encrypted in host-key.
}>} 3.5. TGT traverses network from KDC to kinit encrypted in host-key.
}>} 4. Kinit decrypts TGT with host-key found in v5srvtab.
}> Rather than having a srvtab on the host, why not have the host
}> also run the "secure-ID" algorithm (with its own secret seed)?
}>
}> 1) user enters secure-ID code (for example, via unencrypted telnet)
}> 2) host kinit process received user secure-ID code forwards to KDC
}> 3) KDC verifies user secure-ID code, constructs TGT encrypted in
}> hosts secure-ID code, sends to host
}> 4) host generates secure-ID code, uses to decrypt TGT
--
John Hascall ``An ill-chosen word is the fool's messenger.''
Systems Software Engineer, ISU Comp Center + Ames, IA 50011 + 515/294-9551
