PKCS12_parse.3ssl man page
PKCS12_parse — parse a PKCS#12 structure
int PKCS12_parse(PKCS12 *p12, const char *pass, EVP_PKEY **pkey, X509 **cert, STACK_OF(X509) **ca);
PKCS12_parse() parses a PKCS12 structure.
p12 is the PKCS12 structure to parse. pass is the passphrase to use. If successful the private key will be written to *pkey, the corresponding certificate to *cert and any additional certificates to *ca.
The parameters pkey and cert cannot be NULL. ca can be <NULL> in which case additional certificates will be discarded. *ca can also be a valid STACK in which case additional certificates are appended to *ca. If *ca is NULL a new STACK will be allocated.
The friendlyName and localKeyID attributes (if present) on each certificate will be stored in the alias and keyid attributes of the X509 structure.
PKCS12_parse() returns 1 for success and zero if an error occurred.
The error can be obtained from ERR_get_error(3)
Only a single private key and corresponding certificate is returned by this function. More complex PKCS#12 files with multiple private keys will only return the first match.
Only friendlyName and localKeyID attributes are currently stored in certificates. Other attributes are discarded.
Attributes currently cannot be stored in the private key EVP_PKEY structure.
PKCS12_parse was added in OpenSSL 0.9.3