Bug 3150

Summary: DNS names are not case sensitive
Product: Portable OpenSSH Reporter: Jeffrey Walton <noloader>
Component: sshAssignee: Assigned to nobody <unassigned-bugs>
Status: NEW ---    
Severity: enhancement CC: noloader
Priority: P5    
Version: 8.2p1   
Hardware: Other   
OS: Other   

Description Jeffrey Walton 2020-04-18 06:56:15 AEST 
This is a pretty boring report. I hope you don't mind me leaving it as an enhancement. I stumbled across this when caps-lock was accidentally engaged.

$ ssh CRYPTOPP.COM
jwalton@cryptopp.com: Permission denied (publickey,gssapi-keyex,gssapi-with-mic).

$ ssh cryptopp.com
Enter passphrase for key '/home/jwalton/.ssh/id_ed25519':
Last login: Fri Apr 17 14:15:16 2020 from ...

When using the name cryptopp.com, 'noloader@cryptopp.com' was used because of a recipe in ~/.ssh/config. When using the name CRYPTOPP.COM, 'jwalton@cryptopp.com' was used because jwalton is my username on my local machine. It appears the DNS name was not matched when caps-lock was on.

As far as I know, DNS names are not case sensitive.