How to convert PKCS#8-formatted PEM private key to the traditional format?

openssl private-key pem pkcs#8
rkellerm picture rkellerm · Jun 2, 2010 · Viewed 17.7k times · Source

From OpenSSL 1.0 change log:

Make PKCS#8 the default write format for private keys, replacing the traditional format. This form is standardised, more secure and doesn't include an implicit MD5 dependency. [Steve Henson]

However, I need the private key file in the previous, traditional format. Is it possible to convert the pem file from PKCS#8 to the traditional format (using OpenSSL.exe app)?

Thank you very much!

Answer

rkellerm picture rkellerm · Aug 17, 2010

Succeeded to solve that in that way - the request:

openssl req -configconfigfile.cfg -newkey rsa:2048 -keyout newkey.pem -out newreq.pem 365

Then, I converted it to RSA format:

openssl rsa -in newkey.pem -out newkey.pem

Hope that it will help someone.

Related questions

Differences between "BEGIN RSA PRIVATE KEY" and "BEGIN PRIVATE KEY"

Hi I was writing a program that imports private keys from a .pem file and create a private key object to use it later.. the problem I have faced is that some pem files header begin with -----BEGIN PRIVATE KEY----- …

Read More
Convert DER formatted private key file to PEM form

I have a .prv file which is probably DER formatted private key file. This file is used to certificate Cable Modem. I want to convert this file to PEM formatted one. I tried with openssl tool but none of below …

Read More
Unable to load Private Key. (PEM routines:PEM_read_bio:no start line:pem_lib.c:648:Expecting: ANY PRIVATE KEY)

I have a .key file which is PEM formatted private key file. I didn't make this file but I got this from somewhere. I wanted to see its MD5 hash with openssl tool like below command. openssl rsa -in server.…

Read More