[TLS] predictability of inputs in ESNI
Rob Sayre <sayrer@gmail.com> Fri, 01 November 2019 21:28 UTC
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From: Rob Sayre <sayrer@gmail.com>
Date: Fri, 01 Nov 2019 14:27:50 -0700
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Subject: [TLS] predictability of inputs in ESNI
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Hi, I am not sure how important these findings are, but I've noticed three instances of unnecessarily predictable inputs in ESNI: 1) Trailing padding after domain names are zeros. 2) The checksum calculation seems to start with predictable version bytes in draft -04, and in shipping implementations 3) In practice, NSS inserts 8 bytes of zeros at the beginning of its AAD input (<https://github.com/tlswg/draft-ietf-tls-esni/issues/190>) It seems like these values should all be allowed to be opaque, and I am not sure why NSS is prepending zeros to its AAD (although I asked in the github issue). thanks, Rob
- [TLS] predictability of inputs in ESNI Rob Sayre
- Re: [TLS] predictability of inputs in ESNI Eric Rescorla
- Re: [TLS] predictability of inputs in ESNI Rob Sayre
- Re: [TLS] predictability of inputs in ESNI Eric Rescorla
- Re: [TLS] predictability of inputs in ESNI Rob Sayre
- Re: [TLS] predictability of inputs in ESNI Eric Rescorla
- Re: [TLS] predictability of inputs in ESNI Rob Sayre
- Re: [TLS] predictability of inputs in ESNI Christopher Wood