Differences between revisions 3 and 4

ssh

Links Linux/AddSshUserKeyOnly , Cisco/SshLogin , /Linux/Security/LoginHistory

ssh to old servers with unsecure ciphers

error received

Unable to negotiate with 10.10.10.1 port 22: no matching cipher found. Their offer: aes256-cbc,aes128-cbc,3des-cbc

Set key exchange

ssh -oKexAlgorithms=+diffie-hellman-group1-sha1 user@legacyhost
# or in config
    KexAlgorithms +diffie-hellman-group1-sha1

List supported settings

add -G to command line to see active setting

for available settings

ssh -Q cipher       # List supported ciphers
ssh -Q mac          # List supported MACs
ssh -Q key          # List supported public key types
ssh -Q kex          # List supported key exchange algorithms

Convert putty rsa public key to openssl format

Copy rsa key into clipboard and save to /tmp/key.pub e.g.
```
cat - > /tmp/key.pub
```

for key beginning with "---- BEGIN SSH2 PUBLIC KEY ----"

ssh-keygen -i -f /tmp/key.pub
## using ssh-rsa <xxx> output from previous command
$ echo "ssh-rsa <xxx> Name.Surname+Note@domain.com" | sudo tee /home/<user>/.ssh/authorized_keys

-  ⇤ ← Revision 3 as of 2021-02-16 00:05:19 → 
  Size: 780
  Editor: PieterSmit
  Comment:
+   ← Revision 4 as of 2021-06-23 21:02:28 → ⇥
  Size: 1191
  Editor: PieterSmit
  Comment:
-Deletions are marked like this.
+Additions are marked like this.
 Line 24:
+== Convert putty rsa public key to openssl format ==
 1. Copy rsa key into clipboard and save to /tmp/key.pub e.g. {{{
cat - > /tmp/key.pub
}}}
 2. for key beginning with "{{{---- BEGIN SSH2 PUBLIC KEY ----}}}" {{{
ssh-keygen -i -f /tmp/key.pub
## using ssh-rsa <xxx> output from previous command
$ echo "ssh-rsa <xxx> Name.Surname+Note@domain.com" | sudo tee /home/<user>/.ssh/authorized_keys

}}}