Re: [TLS] RSA-PSS in TLS 1.3 (Martin Rex) Fri, 04 March 2016 14:20 UTC

Return-Path: <>
Received: from localhost ( []) by (Postfix) with ESMTP id 374861A01D6 for <>; Fri, 4 Mar 2016 06:20:30 -0800 (PST)
X-Virus-Scanned: amavisd-new at
X-Spam-Flag: NO
X-Spam-Score: -6.251
X-Spam-Status: No, score=-6.251 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, HELO_EQ_DE=0.35, MIME_8BIT_HEADER=0.3, RCVD_IN_DNSWL_HI=-5, SPF_PASS=-0.001] autolearn=ham
Received: from ([]) by localhost ( []) (amavisd-new, port 10024) with ESMTP id FjgPjogK7lmg for <>; Fri, 4 Mar 2016 06:20:26 -0800 (PST)
Received: from ( []) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by (Postfix) with ESMTPS id 431521A022C for <>; Fri, 4 Mar 2016 06:20:26 -0800 (PST)
Received: from ( []) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by (Postfix) with ESMTPS id 881592AE27; Fri, 4 Mar 2016 15:20:24 +0100 (CET)
X-purgate-ID: 152705::1457101224-000073AB-63B2442F/0/0
X-purgate-size: 1023
X-purgate: clean
X-purgate: This mail is considered clean (visit for further information)
X-purgate-Ad: Categorized by eleven eXpurgate (R)
X-purgate-type: clean
X-SAP-SPAM-Status: clean
Received: from ( []) by (Postfix) with ESMTP id 4B752413D2; Fri, 4 Mar 2016 15:20:24 +0100 (CET)
Received: by (Postfix, from userid 10159) id 2A7191A45C; Fri, 4 Mar 2016 15:20:24 +0100 (CET)
In-Reply-To: <20160304145525.1fe5cb63@pc1>
To: =?UTF-8?Q?Hanno_B=C3=B6ck?= <>
Date: Fri, 4 Mar 2016 15:20:24 +0100 (CET)
X-Mailer: ELM [version 2.4ME+ PL125 (25)]
MIME-Version: 1.0
Content-Transfer-Encoding: quoted-printable
Content-Type: text/plain; charset="ISO-8859-1"
Message-Id: <>
From: (Martin Rex)
Archived-At: <>
Subject: Re: [TLS] RSA-PSS in TLS 1.3
X-Mailman-Version: 2.1.15
Precedence: list
List-Id: "This is the mailing list for the Transport Layer Security working group of the IETF." <>
List-Unsubscribe: <>, <>
List-Archive: <>
List-Post: <>
List-Help: <>
List-Subscribe: <>, <>
X-List-Received-Date: Fri, 04 Mar 2016 14:20:30 -0000

Hanno Böck wrote:
> (Martin Rex) wrote:
>> The *huge* advantage of PKCS#1 v1.5 signatures over RSA-PSS and ECDSA
>> signatures is that one can clearly distinguish "wrong public key"
>> from "signature does not fit plaintext" errors, and loosing this
>> capability makes certain kinds of programming goofs (plus a few
>> admin configuration goofs) much harder to distinguish from
>> data corruption during transfer.
> Actually I see this as a disadvantage. Separating different error
> states has been the source of a whole number of vulnerabilities. The
> original Bleichenbacher attack (and all its variants including drown)
> is based on separating different errors, the Vaudenay attack is.

I'm sorry, but this is clueless.
Signature verification is a PUBLIC KEY operation.
You're not creating an oracle with a public key operation.

The examples you cite are about secret key and private key operations
which create oracles.  That isn't even in the same universe.