Error while converting der private key to pem

opensslprivate-keyssl-certificatex509

I have DER private key and certificate. I need to convert them to PEM format. Certificate converted normally, but when i try to convert key this error happens:

# openssl x509 -in client-key.der -inform DER -out private.pem -outform PEM
unable to load certificate
3077748360:error:0D0680A8:asn1 encoding routines:ASN1_CHECK_TLEN:wrong tag:tasn_dec.c:1319:
3077748360:error:0D07803A:asn1 encoding routines:ASN1_ITEM_EX_D2I:nested asn1 error:tasn_dec.c:381:Type=X509_CINF
3077748360:error:0D08303A:asn1 encoding routines:ASN1_TEMPLATE_NOEXP_D2I:nested asn1 error:tasn_dec.c:751:Field=cert_info, Type=X509

What am i doing wrong? client-key.der is in binary format and has been used in JAVA application, now i need to use it in my C aplication

Best Answer

Notice it says "unable to load certificate". The x509 command is for X509 structures, not private keys! Try the rsa command.

Related Solutions

Ssh – Create a public SSH key from the private key

Use the -y option to ssh-keygen:

ssh-keygen -f ~/.ssh/id_rsa -y > ~/.ssh/id_rsa.pub

From the 'man ssh-keygen'

 -y      This option will read a private OpenSSH format file and print an
         OpenSSH public key to stdout.

Specify the private key with the -f option, yours might be dsa instead of rsa. The name of your private key probably contains which you used. The newly generated public key should be the same as the one you generated before.

Windows – How to tell Git for Windows where to find the private RSA key

For Git Bash

If you are running msysgit (I am assuming you are) and are looking to run Git Bash (I recommend it over TortoiseGit, but I lean to the CLI more than GUI now), you need to figure out what your home directory is for Git Bash by starting it then type pwd (On Windows 7, it will be something like C:\Users\phsr I think). While you're in Git Bash, you should mkdir .ssh.

After you have the home directory, and a .ssh folder under that, you want to open PuTTYgen and open the key (.ppk file) you have previously created. Once your key is open, you want to select Conversions -> Export OpenSSH key and save it to HOME\.ssh\id_rsa. After you have the key at that location, Git Bash will recognize the key and use it.

Note: Comments indicate that this doesn't work in all cases. You may need to copy the OpenSSH key to Program Files\Git\.ssh\id_rsa (or Program Files (x86)\Git\.ssh\id_rsa).

For TortoiseGit

When using TortoiseGit, you need to set the SSH key via pacey's directions. You need to do that for every repository you are using TortoiseGit with.