ssh-keygen.exe hangs for end user

[hdatma]

Please answer the following

If it is a terminal issue then please go through wiki
https://github.com/PowerShell/Win32-OpenSSH/wiki/TTY-PTY-support-in-Windows-OpenSSH

"OpenSSH for Windows" version
((Get-Item (Get-Command sshd).Source).VersionInfo.FileVersion)

latest

Server OperatingSystem
((Get-ItemProperty "HKLM:\SOFTWARE\Microsoft\Windows nt\CurrentVersion\" -Name ProductName).ProductName)

Windows 10 Pro

Client OperatingSystem

Windows 10 Pro

What is failing

ssh-keygen.exe -t ed25519 -o -a 100 -f ${HOME}/.ssh/id_ed25519

Expected output

success

Actual output

The command does not terminate.
No output produced at all.

[hdatma]

Problem solved.

Since nobody chimed in, I guess you already know the solution, so I will not share it.

[manojampalam]

We haven't seen this problem yet. It helps the rest of us if you can share how you solved it.

[hdatma]

The command "ssh-keygen.exe -t ed25519 -o -a 100 -f ${HOME}/.ssh/id_ed25519" should interact with the user, asking for a password to protect the private key soon to be generated. In the case of Win32-OpenSSH, however, the interaction fails: the command does not terminate, and you must interrupt it manually. The trick to bypass the interaction is to provide the password directly in the command, as in "ssh-keygen.exe -t ed25519 -o -a 100 -f ${HOME}/.ssh/id_ed25519 -P your-password-here".

[bagajjal]

Not sure why the ssh-keygen hangs for you but it works on my machine (windows 10),

PS E:> .\ssh-keygen.exe -t ed25519 -o -a 100 -f e:\id_ed25519
Generating public/private ed25519 key pair.
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in e:\id_ed25519.
Your public key has been saved in e:\id_ed25519.pub.
The key fingerprint is:
SHA256:Yr1hE36COC63SYnB2l83N8hHOQ5yrSUC1moHmR46TRs user@ip
The key's randomart image is:
+--[ED25519 256]--+
| |
| + |
| E . . |
| . * O + o . |
| = O B S B |
| o * = B # . |
|. + = . B = |
| = + . + . |
| + |
+----[SHA256]-----+

[bagajjal]

Closing this thread as we couldn't reproduce on multiple machines..

[borisbartlog]

Having just encountered this issue myself (and resolved it), I believe the problem results when you try to run ssh-keygen in cygwin. It runs normally through cmd.exe, but hangs as described when run in the cygwin shell.

[Andrew-Archon]

I'm having this issue as well and for me it's specifically occurring when creating a new key by running ssh-keygen within a PowerShell script file using the PowerShell ISE without passing a passphrase parameter into the call.

Repro:
Open PowerShell ISE and enter the following command into the editor: ssh-keygen -t rsa -C "test" -f rsa_id_TEST

Results in the script hanging with no output in the integrated PowerShell window.

[1ycx]

I'm using powershell 7.2 and can confirm this. It hangs on ssh-keygen -t rsa.

Edit: Closed powershell and tried on CMD. It works fine. Then tried on Powershell again. It worked. WHAT ?

[edyoung]

Just a quick note since I hit a related problem and found this issue.

ssh-keygen can prompt for input in several situations. As noted above you can hit this when it wants a password. In my case I hit a problem when the output file specified to -f already existed. In this case it prompts to check if you want to overwrite the file. This can cause a script to hang if there's no input for ssh-keygen to read. Because in the test environment sometimes the file was already there and sometimes it wasn't, this was a bit mystifying to debug.

[grahamas]

I just ran into the same problem in git bash. Same solution of pre-specifying both password and file name.

[lukescharf]

I just experienced this bug this morning with Windows 11 Pro.

ssh-keygen froze at the input-filename prompt under PowerShell (my default shell on Windows).

ssh-keygen succeeded under cmd.exe (not my default shell).

[ForNeVeR]

May it also depend on terminal? In my case, it always gets stuck in Windows Terminal, but works fine in the default conhost.

[malauhoff]

For me it stuck in Windows Terminal, but only if I added the -G parameter. I ended up in using the default filename and renaming later.

[bshoshany]

This happens to me too, on Windows 11 v10.0.22000.1098 with PowerShell 7.2.6. ssh-keygen works fine in Command Prompt, but gets stuck in PowerShell.

[Ctucker9233]

Same issue windows 10 powershell