[openssl] Export P7b file with all the certificate chain into CER file

I have p7b file provided by Thwate.When I am trying to export the certificate in the cer file using the below command, the certificate chain is not included.
Please suggest how to do the same. This CER is required for the importing into the weblogic key store.

openssl pkcs7 -print_certs -in certificate.p7b -out certificate.cer

I had similar problem extracting certificates from a file. This might not be the most best way to do it but it worked for me.

openssl pkcs7 -inform DER -print_certs -in <path of the file> | awk 'split_after==1{n++;split_after=0} /-----END CERTIFICATE-----/ {split_after=1} {print > "cert" n ".pem"}'

The only problem is that any additional certificates in resulted file will not be recognized, as tools don't expect more than one certificate per PEM/DER encoded file. Even openssl itself. Try

openssl x509 -outform DER -in certificate.cer | openssl x509 -inform DER -outform PEM

and see for yourself.

The selected answer didn't work for me, but it's close. I found a tutorial that worked for me and the certificate I obtained from StartCom.

1. Open the .p7b in a text editor.

2. Change the leader and trailer so the file looks similar to this:

   -----BEGIN PKCS7-----
   [... certificate content here ...]
   -----END PKCS7-----
   

For example, my StartCom certificate began with:

    -----BEGIN CERTIFICATE----- 

and ended with:

    -----END CERTIFICATE----- 

3. Save and close the .p7b.

4. Run the following OpenSSL command (works on Ubuntu 14.04.4, as of this writing):

   openssl pkcs7 -print_certs –in pkcs7.p7b -out pem.cer
   

The output is a .cer with the certificate chain.

Reference: http://www.freetutorialssubmit.com/extract-certificates-from-P7B/2206

If you add -chain to your command line, it will export any chained certificates.

http://www.openssl.org/docs/apps/pkcs12.html