In cryptography, PKCS #12 defines an archive file format for storing many cryptography objects as a single file. It is commonly used to bundle a private key with its X.509 certificate or to bundle all the members of a chain of trust.
A PKCS #12 file may be encrypted and signed. The internal storage containers, called "SafeBags", may also be encrypted and signed. A few SafeBags are predefined to store certificates, private keys and CRLs. Another SafeBag is provided to store any other data at individual implementer's choice.
PKCS #12 is one of the family of standards called Public-Key Cryptography Standards (PKCS) published by RSA Laboratories.
Privacy-Enhanced Mail (PEM) is a de facto file format for storing and sending cryptographic keys, certificates, and other data, based on a set of 1993 IETF standards defining "privacy-enhanced mail." While the original standards were never broadly adopted and were supplanted by PGP and S/MIME, the textual encoding they defined became very popular. The PEM format was eventually formalized by the IETF in RFC 7468.
If you already have a .P12 certificate password signed provided by someone and you need to convert it a .PEM, this can be done like so:
To convert .p12 certificate :
# Initialize variable
cert_p12_in=your-domain-name-cert.p12
cert_p12_pass='XXXZZZYYYPPPQQQ'
cert_pem_out=your-domain-name-cert.pem
# Extract the private key
openssl pkcs12 -in $cert_p12_in -nocerts -nodes -passin "pass:$cert_p12_pass" 2>/dev/null | sed -ne '/-BEGIN PRIVATE KEY-/,/-END PRIVATE KEY-/p' > $cert_pem_out
# Extract the certificate
openssl pkcs12 -in $cert_p12_in -clcerts -nokeys -passin "pass:$cert_p12_pass" 2>/dev/null | sed -ne '/-BEGIN CERTIFICATE-/,/-END CERTIFICATE-/p' >> $cert_pem_out
# Extract the Chain certificate, potentially nothing
openssl pkcs12 -in $cert_p12_in -cacerts -nokeys -chain -passin "pass:$cert_p12_pass" 2>/dev/null | sed -ne '/-BEGIN CERTIFICATE-/,/-END CERTIFICATE-/p' >> $cert_pem_out
# Display the result
cat $cert_pem_out
That's all you should have the .p12 to .pem successfully converted.
Cheers ! 🙂
