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[Ssh] Re: PQ signatures - where do we want to end up?

Peter Gutmann <pgut001@cs.auckland.ac.nz> Tue, 28 April 2026 12:23 UTC

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From: Peter Gutmann <pgut001@cs.auckland.ac.nz>
To: Stephen Farrell <stephen.farrell@cs.tcd.ie>, "ssh@ietf.org" <ssh@ietf.org>
Thread-Topic: [Ssh] PQ signatures - where do we want to end up?
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Date: Tue, 28 Apr 2026 12:23:42 +0000
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Subject: [Ssh] Re: PQ signatures - where do we want to end up?
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Stephen Farrell <stephen.farrell@cs.tcd.ie> writes:

>which of the bazillion options we think might actually be implemented and get
>deployed.

It's SSH, all of them of course.

(Take a look at the SSH_MSG_KEXINIT from widely-used clients some time, here's
 an extract from one of them).

 sntrup761x25519-sha512,sntrup761x25519-sha512@openssh.com,mlkem768x25519-
 sha256,mlkem1024nistp384-sha384,mlkem768nistp256-sha256,curve448-
 sha512,curve25519-sha256,curve25519-sha256@libssh.org,ecdh-sha2-
 nistp256,ecdh- sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-
 exchange-sha256,diffie- hellman-group-exchange-sha1,diffie-hellman-group18-
 sha512,diffie-hellman- group17-sha512,diffie-hellman-group16-sha512,diffie-
 hellman-group15- sha512,diffie-hellman-group14-sha256,diffie-hellman-group14-
 sha1,rsa2048- sha256,rsa1024-sha1,diffie-hellman-group1-sha1,ext-info-c,kex-
 strict-c- v00@openssh.com...{ssh-ed25519,ecdsa-sha2-nistp256,rsa-
 sha2-512,rsa- sha2-256,ssh-rsa,ssh-ed448,ecdsa-sha2-nistp384,ecdsa-sha2-
 nistp521,ssh- dss....aes256-ctr,aes256-cbc,rijndael-
 cbc@lysator.liu.se,aes192-ctr,aes192- cbc,aes128-ctr,aes128-cbc,chacha20-
 poly1305@openssh.com,aes128- gcm@openssh.com,aes256-gcm@openssh.com,3des-
 ctr,3des-cbc,blowfish- ctr,blowfish-cbc,arcfour256,arcfour128....aes256-
 ctr,aes256-cbc,rijndael- cbc@lysator.liu.se,aes192-ctr,aes192-cbc,aes128-
 ctr,aes128-cbc,chacha20- poly1305@openssh.com,aes128-gcm@openssh.com,aes256-
 gcm@openssh.com,3des- ctr,3des-cbc,blowfish-ctr,blowfish-
 cbc,arcfour256,arcfour128....hmac- sha2-256,hmac-sha2-512,hmac-sha1,hmac-
 sha1-96,hmac-md5,hmac-sha2-256- etm@openssh.com,hmac-sha2-512-
 etm@openssh.com,hmac-sha1-etm@openssh.com,hmac- sha1-96-etm@openssh.com,hmac-
 md5-etm@openssh.com....hmac-sha2-256,hmac- sha2-512,hmac-sha1,hmac-
 sha1-96,hmac-md5,hmac-sha2-256-etm@openssh.com,hmac- sha2-512-
 etm@openssh.com,hmac-sha1-etm@openssh.com,hmac-sha1-96- etm@openssh.com,hmac-
 md5-etm@openssh.com

Peter.

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