SSH: Conversions between OpenSSH Keys (Public/Private) and Putty Keys (PPK)

ssh_key_conversions.sh

# it turns out that puttygen can do almost all conversions anyway

: '
ssh-private-public - Convert an openssh private key to an openssh public key

Usage: ssh-private-public <path-to-key> <path-to-key.pub>
'
ssh-private-public () {
    ssh-keygen -f "$1" -y >"$2"
}

: '
ssh-private-ppk - Convert an openssh private key to a putty ppk

Usage: ssh-private-ppk <path-to-key> <path-to-key.ppk>
'
ssh-private-ppk () {
    puttygen "$1" -O private -o "$2"
}

: '
ssh-ppk-public - Convert a putty ppk to an openssh public key

Usage: ssh-ppk-public <path-to-key.ppk> <path-to-key.pub>
'
ssh-ppk-public () {
    puttygen "$1" -O public-openssh -o "$2"
}

: '
ssh-ppk-private - Convert a putty ppk to an openssh private key

Usage: ssh-ppk-private <path-to-key.ppk> <path-to-key>
'
ssh-ppk-private () {
    puttygen "$1" -O private-openssh -o "$2"
}