[Suit] COSE_Sign vs. COSE_Mac
Russ Housley <housley@vigilsec.com> Mon, 04 June 2018 15:15 UTC
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From: Russ Housley <housley@vigilsec.com>
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Date: Mon, 04 Jun 2018 11:16:11 -0400
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Subject: [Suit] COSE_Sign vs. COSE_Mac
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I am struggling to see a case where COSE_Mac provides acceptable protection. With a MAC, the sender and the recipient must use the same key. This means that any recipient can make a modification and produce a valid MAC for the modified object. With a digital signature, the sender uses a private key, and the recipients use a public key, so the recipients cannot produce modified objects. Why accept this possibility? Russ
- [Suit] COSE_Sign vs. COSE_Mac Russ Housley
- Re: [Suit] COSE_Sign vs. COSE_Mac Brendan Moran
- Re: [Suit] COSE_Sign vs. COSE_Mac Russ Housley
- Re: [Suit] COSE_Sign vs. COSE_Mac Koen Zandberg
- Re: [Suit] COSE_Sign vs. COSE_Mac Russ Housley
- Re: [Suit] COSE_Sign vs. COSE_Mac David Brown
- Re: [Suit] COSE_Sign vs. COSE_Mac Derek Atkins
- Re: [Suit] COSE_Sign vs. COSE_Mac Thomas C. Schmidt
- Re: [Suit] COSE_Sign vs. COSE_Mac David Brown
- Re: [Suit] COSE_Sign vs. COSE_Mac Brendan Moran
- Re: [Suit] COSE_Sign vs. COSE_Mac Jim Schaad