Verisign provides the Microsoft Code Signing Certificate as Personal Information Exchange (.pfx) Files. To sign a iOS .mobileconfig file you will need to first extract the Private Key and the Software Publisher Certificate from this .pfx file provided by Verisign.
To extract the Private Key from the .pfx file:
# openssl pkcs12 -in code_signing_certificate_.pfx -nocerts -nodes -out mykey.pem
To extract the Software Publisher Certificate from the .pfx file:
# openssl pkcs12 -in code_signing_certificate.pfx -nokeys -out mycert.pem
Next you will need to download the Verisign Intermediate CA Certificates for Code Signing Certificate. At the time of this writing, these were available at the forllowing URL:
https://knowledge.verisign.com/support/code-signing-support/index?page=content&id=AR1739
Download and save the Intermediary CA Cert as a .crt file (e.g. inter.crt)
Now we are ready to sign the .mobileconfig file. Using OpenSSL:
# openssl smime -sign -in unsigned.mobileconfig -out signed.mobileconfig -signer mycert.pem -inkey mykey.pem -certfile inter.crt -outform der -nodetach
signed.mobileconfig is the .mobileconfig file that you need to deploy to your iOS device. If the signing was successful, iOS should be able to verify the signature on this .mobileconfig file.
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