Provided by: libio-socket-ssl-perl_2.085-1_all 
NAME
IO::Socket::SSL::Utils -- loading, storing, creating certificates and keys
SYNOPSIS
use IO::Socket::SSL::Utils;
$cert = PEM_file2cert('cert.pem'); # load certificate from file
my $hash = CERT_asHash($cert); # get details from certificate
PEM_cert2file($cert,'cert.pem'); # write certificate to file
CERT_free($cert); # free memory within OpenSSL
@certs = PEM_file2certs('chain.pem'); # load multiple certificates from file
PEM_certs2file('chain.pem', @certs); # write multiple certificates to file
CERT_free(@certs); # free memory for all within OpenSSL
my $cert = PEM_string2cert($pem); # load certificate from PEM string
$pem = PEM_cert2string($cert); # convert certificate to PEM string
$key = KEY_create_rsa(2048); # create new 2048-bit RSA key
PEM_key2file($key,"key.pem"); # and write it to file
KEY_free($key); # free memory within OpenSSL
DESCRIPTION
This module provides various utility functions to work with certificates and private keys, shielding some
of the complexity of the underlying Net::SSLeay and OpenSSL.
FUNCTIONS
• Functions converting between string or file and certificates and keys. They croak if the operation
cannot be completed.
PEM_file2cert(file) -> cert
PEM_cert2file(cert,file)
PEM_file2certs(file) -> @certs
PEM_certs2file(file,@certs)
PEM_string2cert(string) -> cert
PEM_cert2string(cert) -> string
PEM_file2key(file) -> key
PEM_key2file(key,file)
PEM_string2key(string) -> key
PEM_key2string(key) -> string
• Functions for cleaning up. Each loaded or created cert and key must be freed to not leak memory.
CERT_free(@certs)
KEY_free(@keys)
• KEY_create_rsa(bits) -> key
Creates an RSA key pair, bits defaults to 2048.
• KEY_create_ec(curve) -> key
Creates an EC key, curve defaults to "prime256v1".
• CERT_asHash(cert,[digest_algo]) -> hash
Extracts the information from the certificate into a hash and uses the given digest_algo (default:
SHA-256) to determine digest of pubkey and cert. The resulting hash contains:
subject Hash with the parts of the subject, e.g. commonName, countryName, organizationName,
stateOrProvinceName, localityName. If there are multiple values for any of these parts the
hash value will be an array ref with the values in order instead of just a scalar.
subjectAltNames
Array with list of alternative names. Each entry in the list is of "[type,value]", where
"type" can be OTHERNAME, EMAIL, DNS, X400, DIRNAME, EDIPARTY, URI, IP or RID.
issuer Hash with the parts of the issuer, e.g. commonName, countryName, organizationName,
stateOrProvinceName, localityName. If there are multiple values for any of these parts the
hash value will be an array ref with the values in order instead of just a scalar.
not_before, not_after
The time frame, where the certificate is valid, as time_t, e.g. can be converted with
localtime or similar functions.
serial The serial number
crl_uri List of URIs for CRL distribution.
ocsp_uri
List of URIs for revocation checking using OCSP.
keyusage
List of keyUsage information in the certificate.
extkeyusage
List of extended key usage information from the certificate. Each entry in this list consists
of a hash with oid, nid, ln and sn.
pubkey_digest_xxx
Binary digest of the pubkey using the given digest algorithm, e.g. pubkey_digest_sha256 if
(the default) SHA-256 was used.
x509_digest_xxx
Binary digest of the X.509 certificate using the given digest algorithm, e.g.
x509_digest_sha256 if (the default) SHA-256 was used.
fingerprint_xxx
Fingerprint of the certificate using the given digest algorithm, e.g. fingerprint_sha256 if
(the default) SHA-256 was used. Contrary to digest_* this is an ASCII string with a list if
hexadecimal numbers, e.g. "73:59:75:5C:6D...".
signature_alg
Algorithm used to sign certificate, e.g. "sha256WithRSAEncryption".
ext List of extensions. Each entry in the list is a hash with oid, nid, sn, critical flag
(boolean) and data (string representation given by X509V3_EXT_print).
version Certificate version, usually 2 (x509v3)
• CERT_create(hash) -> (cert,key)
Creates a certificate based on the given hash. If the issuer is not specified the certificate will
be self-signed. The following keys can be given:
subject Hash with the parts of the subject, e.g. commonName, countryName, ... as described in
"CERT_asHash". Default points to IO::Socket::SSL.
not_before
A time_t value when the certificate starts to be valid. Defaults to current time.
not_after
A time_t value when the certificate ends to be valid. Defaults to current time plus one 365
days.
serial The serial number. If not given a random number will be used.
version The version of the certificate, default 2 (x509v3).
CA true|false
If true declare certificate as CA, defaults to false.
purpose string|array|hash
Set the purpose of the certificate. The different purposes can be given as a string
separated by non-word character, as array or hash. With string or array each purpose can be
prefixed with '+' (enable) or '-' (disable) and same can be done with the value when given as
a hash. By default enabling the purpose is assumed.
If the CA option is given and true the defaults "ca,sslca,emailca,objca" are assumed, but can
be overridden with explicit purpose. If the CA option is given and false the defaults
"server,client" are assumed. If no CA option and no purpose is given it defaults to
"server,client".
Purpose affects basicConstraints, keyUsage, extKeyUsage and netscapeCertType. The following
purposes are defined (case is not important):
client
server
email
objsign
CA
sslCA
emailCA
objCA
emailProtection
codeSigning
timeStamping
digitalSignature
nonRepudiation
keyEncipherment
dataEncipherment
keyAgreement
keyCertSign
cRLSign
encipherOnly
decipherOnly
Examples:
# root-CA for SSL certificates
purpose => 'sslCA' # or CA => 1
# server certificate and CA (typically self-signed)
purpose => 'sslCA,server'
# client certificate
purpose => 'client',
ext [{ sn => .., data => ... }, ... ]
List of extensions. The type of the extension can be specified as name with "sn" or as NID
with "nid" and the data with "data". These data must be in the same syntax as expected within
openssl.cnf, e.g. something like "OCSP;URI=http://...". Additionally the critical flag can be
set with "critical =" 1>.
key key use given key as key for certificate, otherwise a new one will be generated and returned
issuer_cert cert
set issuer for new certificate
issuer_key key
sign new certificate with given key
issuer [ cert, key ]
Instead of giving issuer_key and issuer_cert as separate arguments they can be given both
together.
digest algorithm
specify the algorithm used to sign the certificate, default SHA-256.
ignore_invalid_args
ignore any unknown arguments which might be in the argument list (which might be in the
arguments for example as result from CERT_asHash)
AUTHOR
Steffen Ullrich