CMSGenerator - Reference Documentation

Class for CMS generation according to RFC 3852

Index of Methods

CMSGenerator() constructor
setDataContent()
addSigner()
generate()

Constants

Type	Name	Description
Number	TYPE_SIGNED_DATA	Indicator for signed data content
Number	TYPE_ENVELOPED_DATA	Indictator for enveloped data
String	TYPE_DIGESTED_DATA	Indicator for digested data
String	TYPE_ENCRYPTED_DATA	Indicator for encrypted data
String	TYPE_AUTHENTICATED_DATA	Indicator for authenticated data

Constructor

Prototype

CMSGenerator(Number type)

Description

Create a CMS generator object for the specified type

Note: The current implementation only supports signed data

Arguments

Type	Name	Description
`Number`	type	Type of CMS object that should be generated

Exceptions

Name	Value	Description
GPError	GPError.GPError.INVALID_TYPE	Argument type is invalid
GPError	GPError.INVALID_DATA	Argument contains no valid encoded CMS signed data object

Example


try {
	var gen = new CMSGenerator(CMSGenerator.TYPE_ENVELOPED_DATA);
} catch (e) {
	assert(e instanceof GPError);
}

try {
	var gen = new CMSGenerator(CMSGenerator.TYPE_DIGESTED_DATA);
} catch (e) {
	assert(e instanceof GPError);
}

try {
	var gen = new CMSGenerator(CMSGenerator.TYPE_ENCRYPTED_DATA);
} catch (e) {
	assert(e instanceof GPError);
}

try {
	var gen = new CMSGenerator(CMSGenerator.TYPE_AUTHENTICATED_DATA);
} catch (e) {
	assert(e instanceof GPError);
}

var gen = new CMSGenerator(CMSGenerator.TYPE_SIGNED_DATA);
assert(gen != null);

setDataContent()

Prototype

void setDataContent(ByteString data)

Description

Set the data content of the CMS object.

Arguments

Type	Name	Description
`ByteString`	data	Data content

Return

Exceptions

Name	Value	Description
GPError	GPError.INVALID_ARGUMENTS	Too many or missing arguments in call

Example


var content = new ByteString("Hello World!", ASCII);
gen.setDataContent(content);

addSigner()

Prototype

void addSigner(Key privateKey, X509 certificate, String digestOID)

Description

Add a signer key for the object.

Arguments

Type	Name	Description
`Key`	privateKey	Private key of the signer
`X509`	certificate	Certificate of the signer
`ByteString`	digestOID	OID of the corresponding digest algorithm

Return

Exceptions

Name	Value	Description
GPError	GPError.INVALID_ARGUMENTS	Too many or missing arguments in call

Example



var crypto = new Crypto();

// Generate an asymmetric key pair and a certificate for A
print("Generating generating key pair and X509 certificate for Signer A...\n");

var privKeyA = new Key();
privKeyA.setType(Key.PRIVATE);

var pubKeyA = new Key();
pubKeyA.setType(Key.PUBLIC);
pubKeyA.setSize(2048);
	
crypto.generateKeyPair(Crypto.RSA, pubKeyA, privKeyA);
	
var x = new X509CertificateGenerator(crypto);

x.reset();
x.setSerialNumber(new ByteString("01", HEX));
x.setSignatureAlgorithm(Crypto.RSA);
var issuer = { C:"UT", O:"ACME Corporation", CN:"Test-CA" };
x.setIssuer(issuer);
x.setNotBefore("060825120000Z");
x.setNotAfter("160825120000Z");
var subject = { C:"UT", O:"Utopia CA", OU:"ACME Corporation", CN:"Signer #A" };
x.setSubject(subject);
x.setPublicKey(pubKeyA);
x.addKeyUsageExtension(	X509CertificateGenerator.digitalSignature |
							X509CertificateGenerator.keyCertSign |
							X509CertificateGenerator.cRLSign );
							
x.addBasicConstraintsExtension(true, 0);
x.addSubjectKeyIdentifierExtension();
x.addAuthorityKeyIdentifierExtension(pubKeyA);

var certA = x.generateX509Certificate(privKeyA);

gen.addSigner(privKeyA, certA, new ByteString("id-sha256", OID), true);

generate()

Prototype

ByteString generate()

ByteString generate(ByteString contentOID)

Description

Generate the CMS object

Return

ByteString The ASN.1 encoded cms object

Exceptions

Name	Value	Description
GPError	GPError.INVALID_ARGUMENTS	Too many or missing arguments in call

Example


var contentOID = new ByteString("0.4.0.127.0.7.3.2.2", OID);

var cms = gen.generate(contentOID);

var t = new CMSSignedData(cms);

var contentTypeOID = t.getEContentType();
assert(contentTypeOID.equals(contentOID));

certs = t.getSignedDataCertificates();

assert(certs != null);

print("Number of certificates: " + certs.length);

for (i = 0; i < certs.length; i++) {
	print("#" + i+ ": " + certs[i].toString());
}

print("Signed content: " + t.getSignedContent().toString(ASCII));


ns = t.getNumberOfSigners();
for (i = 0; i < ns; i++) {

	signature = t.getSignerInfoSignature(i);
	assert(signature != null);
	print("Signature [" + i + "]: " + signature.toString());
}

ns = t.getNumberOfSigners();
assert(ns != null);

print("Number of signers:" + ns);

for (i = 0; i < ns; i++) {

	valid = t.isSignerInfoSignatureValid(i);
	assert(valid != null);
	print("Signer information signature [" + i + "]: " + (valid == true ? "valid" : "invalid"));
}