Filename extension | .p12, .pfx |
---|---|
Uniform Type Identifier (UTI) | 0 |
Developed by | RSA Security |
Initial release | 1996 |
Latest release |
PKCS #12 v1.1
(27 October 2012 ) |
Type of format | Archive file format |
Container for | X.509 public key certificates, X.509 private keys, X.509 CRLs, generic data |
Extended from | Microsoft PFX file format |
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.
The filename extension for PKCS #12 files is ".p12
" or ".pfx
".
These files can be created, parsed and read out with the OpenSSL pkcs12
command.
PKCS #12 is the successor to Microsoft's "PFX", however, the terms "PKCS #12 file" and "PFX file" are sometimes used interchangeably.
Microsoft's "PFX" has received heavy criticism of being one of the most complex cryptographic protocols.
The full PKCS #12 standard is very complex. It enables buckets of complex objects such as PKCS #8 structures, nested deeply. But in practice it is normally used to store just one private key and its associated certificate chain.
PKCS #12 files are usually created using OpenSSL, which only support a single private key from the command line interface. The Java keytool can be used to create multiple "entries" since Java 8, but that may be incompatible with many other systems. The upcoming version of KMIP will also be able to create PKCS #12 files directly.
A simpler, alternative format to PKCS #12 is PEM which just lists the certificates and possibly private keys as Base 64 strings in a text file.