similar to: Suggestion: Deprecate SSH certificates and move to X.509 certificates

That's not a very good source, since it's only available to one person. On Fri, May 25, 2018 at 7:12 AM, Peter Moody <mindrot at hda3.com> wrote: > On Thu, May 24, 2018 at 9:09 PM, Yegor Ievlev <koops1997 at gmail.com> wrote: >> How can I revoke one SSH certificate without having to replace the >> root certificate and all certificates signed by it? > >

How can I revoke one SSH certificate without having to replace the root certificate and all certificates signed by it? Regarding the second statement, do you have sources? On Fri, May 25, 2018 at 6:58 AM, Peter Moody <mindrot at hda3.com> wrote: > On Thu, May 24, 2018 at 8:36 PM, Yegor Ievlev <koops1997 at gmail.com> wrote: > >> SSH certificates provide no >> way to

Zero matches in both. https://linux.die.net/man/5/sshd_config https://linux.die.net/man/5/ssh_config On Fri, May 25, 2018 at 7:48 AM, Damien Miller <djm at mindrot.org> wrote: > On Fri, 25 May 2018, Yegor Ievlev wrote: > >> Please tell me in technical details how current revocation support >> works, or give links. Then I will be able to give an answer. > > Please

Please tell me in technical details how current revocation support works, or give links. Then I will be able to give an answer. On Fri, May 25, 2018 at 7:16 AM, Damien Miller <djm at mindrot.org> wrote: > > > On Fri, 25 May 2018, Yegor Ievlev wrote: > >> Can you implement revocation support? > > What do you want that the existing revocation support lacks?

Can you implement revocation support? On Fri, May 25, 2018 at 6:55 AM, Damien Miller <djm at mindrot.org> wrote: > No way, sorry. > > The OpenSSH certificate format was significantly motivated by X.509's > syntactic and semantic complexity, and the consequent attack surface in > the sensitive pre-authentication paths of our code. We're very happy to > be able to

e.g. can we make it throw warnings etc. rsa-sha2-256 and rsa-sha2-512 are fine, they use PSS. On Sun, Jan 20, 2019 at 1:55 AM Yegor Ievlev <koops1997 at gmail.com> wrote: > > Also can we do anything with ssh-rsa? It uses both SHA-1 and > deprecated PKCS#1 padding. If it's used to sign certificates, there's > no additional protection of SHA-2 hashing before SHA-1

I don't think there is any point to generate so many moduli. Actually, 3 moduli of sizes 2048, 3072 and 4096 seem like a sane choice. On Fri, Feb 15, 2019 at 7:58 AM Darren Tucker <dtucker at dtucker.net> wrote: > > On Fri, 15 Feb 2019 at 14:22, Yegor Ievlev <koops1997 at gmail.com> wrote: > > I'm not nearly knowledgeable enough in crypto to fully understand your

I'm not sure if collision resistance is required for DH key derivation, but generally, SHA-1 is on its way out. If it's possible (if there's not a very large percentage of servers that do not support anything newer), it should be disabled.

The defaults for HostKeyAlgorithms option are: ecdsa-sha2-nistp256-cert-v01 at openssh.com, ecdsa-sha2-nistp384-cert-v01 at openssh.com, ecdsa-sha2-nistp521-cert-v01 at openssh.com, ssh-ed25519-cert-v01 at openssh.com, ssh-rsa-cert-v01 at openssh.com, ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521, ssh-ed25519,ssh-rsa Why does OpenSSH prefer older and less secure

On Sat, 26 May 2018, Christian Weisgerber wrote: > On 2018-05-25, Yegor Ievlev <koops1997 at gmail.com> wrote: > > > The defaults for HostKeyAlgorithms option are: [...] > > Why does OpenSSH prefer older and less secure > > (https://safecurves.cr.yp.to/) ECDSA with NIST curves over Ed25519? > > I asked Markus and Damien about this in the past but honestly

That doesn't seem to be the case. See https://nvlpubs.nist.gov/nistpubs/SpecialPublications/NIST.SP.800-57pt1r4.pdf (5.6.1 Comparable Algorithm Strengths) On Fri, Feb 15, 2019 at 8:28 AM Darren Tucker <dtucker at dtucker.net> wrote: > > On Fri, 15 Feb 2019 at 16:00, Yegor Ievlev <koops1997 at gmail.com> wrote: > > I don't think there is any point to generate so

there are more implications to changing key algorithms than KEX algorithms. If a change is made to the specification, then it might invalidate all the keys that are out there, this isn't the case with any other negotiated algorithm, On Sun, 27 May 2018, Yegor Ievlev wrote: > I don't think we should wait for a RFC in order to use stronger > crypto. We already prefer Curve25519 for

Also, how are default moduli shipped with OpenSSH for use in diffie-hellman-group-exchange-sha1/sha256 chosen? Are they chosen randomly by developers or are they chosen for security properties? If they are random, why not use moduli from RFC 7919 instead, like Mozilla recommends? On Fri, Feb 15, 2019 at 3:48 AM Mark D. Baushke <mdb at juniper.net> wrote: > > Yegor Ievlev <koops1997

I'm not nearly knowledgeable enough in crypto to fully understand your answer, but I will try. I wonder why moduli are not automatically generated the first time sshd is started though. That would make much more sense than shipping a default moduli file but also asking everyone to replace it with their own. On Fri, Feb 15, 2019 at 5:50 AM Mark D. Baushke <mdb at juniper.net> wrote: >

Also, Jerry Solinas, the person listed as an author of the curves, also is the author of DUAL_EC_DRBG. On Tue, May 29, 2018 at 3:43 AM, Damien Miller <djm at mindrot.org> wrote: > On Tue, 29 May 2018, Damien Miller wrote: > >> We're aware of those arguments but don't find them convincing enough to >> switch early. > > (but we will be switching to ssh-ed25519

Can we disable diffie-hellman-group14-sha1 too? On Thu, Feb 14, 2019 at 10:23 PM Mark D. Baushke <mdb at juniper.net> wrote: > > Hi John, > > The short answer is YES. > > Jon DeVree <nuxi at vault24.org> writes: > > > I ask because the removal of diffie-hellman-group-exchange-sha1 happened > > accidently in 7.8 due to a mistake in a change to

I referred to the fact that there is no value for 4096-bit groups at all. For higher strengths than 128 bits one should probably not use non-EC crypto at all, as the document suggests. On Fri, Feb 15, 2019 at 9:19 AM Darren Tucker <dtucker at dtucker.net> wrote: > > On Fri, 15 Feb 2019 at 16:45, Yegor Ievlev <koops1997 at gmail.com> wrote: > > That doesn't seem to be

Steps to reproduce: 1. Run a SSH server with default configuration and point a domain to it. 2. Add SSHFP record to the domain, but only for Ed25519 key. 3. Attempt to connect with VerifyHostKeyDNS set to yes, but the rest of settings set to defaults. 4. OpenSSH defaults to ECDSA instead of Ed25519 and refuses connection because there is no ECDSA fingerprint in SSHFP records. A stopgap solution

On Mon, 28 May 2018, Yegor Ievlev wrote: > Can we prefer RSA to ECDSA? For example: > HostKeyAlgorithms > ssh-rsa,ssh-ed25519,ecdsa-sha2-nistp521,ecdsa-sha2-nistp384,ecdsa-sha2-nistp256 not without a good reason

Hi All, Version 7.0 of "X.509 certificates support in OpenSSH" is ready for immediate download. This version allow client to use certificates and keys stored into external devices. The implementation is based on openssl dynamic engines. For instance E_NSS engine ( http://developer.berlios.de/projects/enss ) will allow you to use certificates and keys from Firefox, SeaMonkey,