OpenSSH: Add alias name for sntrup761x25519-sha512 key exchange

This makes sure OpenSSH connections make use of this post-quantum
key exchange whenever possible, even if one peer still running
OpenSSH 9.8 or older.

Signed-off-by: Peter Müller <peter.mueller@ipfire.org>
Signed-off-by: Michael Tremer <michael.tremer@ipfire.org>

diff --git a/config/ssh/ssh_config b/config/ssh/ssh_config
index 5a9ad85c5c254af94c03f0d2b6ddb673da339db9..86f123e283b42c577184c3e1343b343371749e81 100644 (file)
--- a/config/ssh/ssh_config
+++ b/config/ssh/ssh_config
@@ -9,7 +9,7 @@ Host *
         UseRoaming no
 
         # Only use secure crypto algorithms
-        KexAlgorithms sntrup761x25519-sha512,mlkem768x25519-sha256,curve25519-sha256,curve25519-sha256@libssh.org,diffie-hellman-group-exchange-sha256
+        KexAlgorithms sntrup761x25519-sha512,sntrup761x25519-sha512@openssh.com,mlkem768x25519-sha256,curve25519-sha256,curve25519-sha256@libssh.org,diffie-hellman-group-exchange-sha256
         Ciphers chacha20-poly1305@openssh.com,aes256-gcm@openssh.com,aes128-gcm@openssh.com,aes256-ctr,aes192-ctr,aes128-ctr
         MACs hmac-sha2-512-etm@openssh.com,hmac-sha2-256-etm@openssh.com,umac-128-etm@openssh.com,hmac-sha2-512,hmac-sha2-256,umac-128@openssh.com
 

diff --git a/config/ssh/sshd_config b/config/ssh/sshd_config
index 9229b6518161b15a0192b9f8a3d31aad0434fa44..4214167054665ec670dc6843c4ef1f27251b5425 100644 (file)
--- a/config/ssh/sshd_config
+++ b/config/ssh/sshd_config
@@ -20,7 +20,7 @@ LoginGraceTime 30s
 MaxStartups 5
 
 # Only allow safe crypto algorithms
-KexAlgorithms sntrup761x25519-sha512,mlkem768x25519-sha256,curve25519-sha256,curve25519-sha256@libssh.org,diffie-hellman-group-exchange-sha256
+KexAlgorithms sntrup761x25519-sha512,sntrup761x25519-sha512@openssh.com,mlkem768x25519-sha256,curve25519-sha256,curve25519-sha256@libssh.org,diffie-hellman-group-exchange-sha256
 Ciphers chacha20-poly1305@openssh.com,aes256-gcm@openssh.com,aes128-gcm@openssh.com,aes256-ctr,aes192-ctr,aes128-ctr
 MACs hmac-sha2-512-etm@openssh.com,hmac-sha2-256-etm@openssh.com,umac-128-etm@openssh.com,hmac-sha2-512,hmac-sha2-256,umac-128@openssh.com