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Re: [TLS] TLS 1.2 - is it allowed to strip the leading zero byte(s) in RSA signature in ServerKeyExchange?

Peter Gutmann <pgut001@cs.auckland.ac.nz> Thu, 13 February 2020 15:42 UTC

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From: Peter Gutmann <pgut001@cs.auckland.ac.nz>
To: David Benjamin <davidben@chromium.org>
CC: M K Saravanan <mksarav@gmail.com>, "<tls@ietf.org>" <tls@ietf.org>
Thread-Topic: [TLS] TLS 1.2 - is it allowed to strip the leading zero byte(s) in RSA signature in ServerKeyExchange?
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Date: Thu, 13 Feb 2020 15:42:50 +0000
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Subject: Re: [TLS] TLS 1.2 - is it allowed to strip the leading zero byte(s) in RSA signature in ServerKeyExchange?
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David Benjamin <davidben@chromium.org> writes:

>Note that bignum libraries that perform leading-zero truncation

like OpenSSL, and some PKCS #11 libraries

>are unlikely to be suitable for cryptography anyway.

OK, I'll keep that in mind: OpenSSL and PKCS #11 are unlikely to be suitable
for cryptography :-).

Peter.

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