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encryptionopensslprivate-keyopenssh

Unable to encrypt private key using openssl

I have generate Rsa Key pairs using openssh. I want to encrypt private key with passphrase using openssl.

I tried to encrypt private key using openssl , but unable to do that as it is giving error message.

Used the below command to generate rsa key pair

ssh-keygen -t rsa -b 4096 -P ''-f ./Test-key

used below command to encrypt private key using openssl.

rsa -des3 -in C:\Users\vkode200\Test-key -out C:\Users\vkode200\Test-key-encrypted -passout pass:"${pass}"

I am getting below error message :

15764:error:0906D06C:PEM routines:PEM_read_bio:no start line:crypto\pem\pem_lib.c:686:Expecting: ANY PRIVATE KEY
error in rsa```

Below is the header of my generated private key
```-----BEGIN OPENSSH PRIVATE KEY-----```
I have no clue and i spent lot of time to figure out the issue, but no luck.
Solution

  • You can generate keys in old format by passing -m PEM:

    ssh-keygen -t rsa -b 4096 -P '' -f ./Test-key -m PEM

    Those should work fine with that openssl command.

    If you need them in new format, you can make a copy a convert it in place with:

    ssh-keygen -p -P '' -N '' -f ./Test-key -m PEM