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SSH key on github - Windows and Linux

Ryan Souza on January 05, 2024

What is an SSH key? Generating an SSH key Linux Windows References What is an SSH key? An SSH key is a pair of keys used to ...

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Trung Ly • Jan 6 '24

Nice article! If I may add:

I'd like to add getting to know the ssh_config file.

# github account
Host github.com
HostName github.com
PreferredAuthentications publickey
IdentityFile ~/.ssh/id_rsa_myaccount_github

# gitlab account
Host gitlab.com
HostName gitlab.com
PreferredAuthentications publickey
IdentityFile ~/.ssh/id_rsa_myaccount_gitlab

# gitlab company account
Host gitlab.my_company.com
HostName gitlab.my_company.com
PreferredAuthentications publickey
IdentityFile ~/.ssh/id_rsa_mycompanyaccount_gitlab

Reference: gist.github.com/alejandro-martin/a...

Lastly, make sure to use the right permissions to avoid this error:

$ ssh localhost
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
@         WARNING: UNPROTECTED PRIVATE KEY FILE!          @
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
Permissions 0777 for '/root/.ssh/id_rsa' are too open.
It is required that your private key files are NOT accessible by others.
This private key will be ignored.
Load key "/root/.ssh/id_rsa": bad permissions
[...]

.ssh directory: 700 (drwx------)
public key (.pub files): 644 (-rw-r--r--)
private key (id_rsa): 600 (-rw-------)

Directory or File	Man Page	Recommended Permissions	Mandatory Permissions
`~/.ssh/`	There is no general requirement to keep the entire contents of this directory secret, but the recommended permissions are read/write/execute for the user, and not accessible by others.	700
`~/.ssh/authorized_keys`	This file is not highly sensitive, but the recommended permissions are read/write for the user, and not accessible by others	600
`~/.ssh/config`	Because of the potential for abuse, this file must have strict permissions: read/write for the user, and not accessible by others. It may be group-writable provided that the group in question contains only the user.		600
`~/.ssh/identity` `~/.ssh/id_dsa` `~/.ssh/id_rsa`	These files contain sensitive data and should be readable by the user but not accessible by others (read/write/execute)		600

Reference: frankindev.com/2020/11/26/permissi...

Ryan Souza • Jan 6 '24

Pretty cool, Having multiple SSH keys looks like something that I'll need in the future. Also, feel free to open a pull request to add this as an Extra Or bonus in the link: github.com/ryrden/ryan.dev/blob/ma...

the post was originally posted at ryan.dev.br/2023-04-17-github-ssh-en/