OpenSSH エンコードされた秘密鍵は、複数行のテキストのまとまりで、次の行で始まります。
-----BEGIN OPENSSH PRIVATE KEY-----
記述は次の行で終わります。
-----END OPENSSH PRIVATE KEY-----
-----BEGIN OPENSSH PRIVATE KEY-----
b3BlbnNzaC1rZXktdjEAAAAACmFlczI1Ni1jYmMAAAAGYmNyeXB0AAAAGAAAABC6qaBfHT
HmQuxY3Bas6CrnAAAAEAAAAAEAAAEVAAAAB3NzaC1yc2EAAAABIwAAAQEAvsfgBxrRrXtT
K6NlFboYvw/1t+BWn27OuykQzGkChEFch4ai8r9aHBtRSPx65cSvlgTMKhbBuyApZTan9J
P3mukwzyryZWupGnR3cXyapJTFoPlk3McLPeBTzZdv5cqIobEKyyqZNPztubpGPQ9CH//h
rYGh6rxHX35HoBcKTGao8mniXdC9mjDXxL6ZlOchlIx+QLgk8IZqLPHVlFD7ZY1NS4h+7c
xKDTlvci+5ylA2uYxS8tF8AQu3n8y7pensbwFWZYjhxpq+4Ft3ZTctcwVbt2Ld/ne5uMET
jrswejJney8pIPQz59FrEriHqdvJyFslbP0MGsA6cKLow7tKaQAAA8C4x8brtTC618rLBT
bh4pg8uUEZcXC/XxR5lCOXWpm4lREvkNzIIZx4zODnHwi+ufIk6Ul41pAizmgkSMwVW0UO
hNMAVGgrV/wV866XC4RvBQkb5magBWjjOkmpwf3t3+/iI+7BfxAlsGK3rHLT7/rZ04km2V
DpGlK9STAEs7NlJ4AQxQAcXqFOzFxkZ0Rba5aqKzVy28WIFgFnwl1xkHYqR61xSTn6UCVy
JAdhftais5YGuPjQXcSyIxjgGl1vxCdAqzjSyNTsy+ztjE5522Bdn+plk1Hw2Ik7g56rNX
fpm9JNt1XgARV8xHenOW22zmXdJE6klNXQ17pfka+pod+8sxekH0K6MqlEfPXoHG/CfksW
RCffqd2oYni4WIRrwL8HQTyvNwMSJGNC6zV7scIJNsQk/LAQCK0k2TI24fAKq72nKiCLeK
UaKSzIpY+UBOJah6Oro9UGxCwZny/E+YNUwPz0ys8UwN0SPz+Jgq/ZJUE0099LhWzRzfjy
poqHKWqFUEkyrCqIwTqusCiXnmaa8rPCIbkDj/l6eyqU6CGzlFZusR1rxtncO4CMrJ94vi
vsB+NQx2+rcBZncU46P6ogjKKrYqLJBQq7EzDHqf2TmYCLdTiwD1kS9fs69IbnrNg7ygFA
paGUlceedbYCxf8sJVq5zCMKILZ7GGdiDh9t+UOueaSk1x7YPNQoSeHr/3OUd7hgu036Sk
HFcf4jIUdpelS7qt9vNzYKkPoZDJUZSkdJFeD+QlTN0HFftLS0XfjKqYf6bAsi0zAD3Rcb
FGM7UBK1ZaSC9NrbOUX/7cFk5G7BsBtfVhnKCO6C0hxsSdkg4do09xFVNZDKzsV49SLbdX
3Ve6NlIt/0R4v6O3e78KiPcLyhec28n+cm7FZg4BwmK3AM/MQPtJXAfkmMg9AfTKlxSN8r
4ZRVks0gxUu/gjnLcSzgb6pU9c4fcpt4OaWvoeVqWjwHzGyvi35i6fvJhQRsqu7Nzct6iG
uqrZu+Fs2+cGUov/ZGVmbG2lAK/mc5dT6XHpH3RndNtzvJbjd68iUyVViBpx+WBY65mYS1
COss8S2aDBvQTfH5glMM61gME2QZGTqmVB0VCXVM8saB3UrmEVItIglpQnlpnUQTPB+Qja
MdXDarWkTqD8KVby26kpBtXKsctbQWnKf059HHb+pptedQq0+VGMQSx8iub+d8l+6SH66D
ugzP/P7TgJ2ECqz104/xk8XOnCQNqNo0gqvnsDx96eGv8UQ9arvAzrEFkt61l/wbIrTzCV
G2yak=
-----END OPENSSH PRIVATE KEY-----