1797 lines
54 KiB
JavaScript
1797 lines
54 KiB
JavaScript
/**
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* Javascript implementation of basic RSA algorithms.
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*
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* @author Dave Longley
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*
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* Copyright (c) 2010-2014 Digital Bazaar, Inc.
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*
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* The only algorithm currently supported for PKI is RSA.
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*
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* An RSA key is often stored in ASN.1 DER format. The SubjectPublicKeyInfo
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* ASN.1 structure is composed of an algorithm of type AlgorithmIdentifier
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* and a subjectPublicKey of type bit string.
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*
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* The AlgorithmIdentifier contains an Object Identifier (OID) and parameters
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* for the algorithm, if any. In the case of RSA, there aren't any.
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*
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* SubjectPublicKeyInfo ::= SEQUENCE {
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* algorithm AlgorithmIdentifier,
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* subjectPublicKey BIT STRING
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* }
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*
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* AlgorithmIdentifer ::= SEQUENCE {
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* algorithm OBJECT IDENTIFIER,
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* parameters ANY DEFINED BY algorithm OPTIONAL
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* }
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*
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* For an RSA public key, the subjectPublicKey is:
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*
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* RSAPublicKey ::= SEQUENCE {
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* modulus INTEGER, -- n
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* publicExponent INTEGER -- e
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* }
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*
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* PrivateKeyInfo ::= SEQUENCE {
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* version Version,
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* privateKeyAlgorithm PrivateKeyAlgorithmIdentifier,
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* privateKey PrivateKey,
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* attributes [0] IMPLICIT Attributes OPTIONAL
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* }
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*
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* Version ::= INTEGER
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* PrivateKeyAlgorithmIdentifier ::= AlgorithmIdentifier
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* PrivateKey ::= OCTET STRING
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* Attributes ::= SET OF Attribute
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*
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* An RSA private key as the following structure:
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*
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* RSAPrivateKey ::= SEQUENCE {
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* version Version,
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* modulus INTEGER, -- n
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* publicExponent INTEGER, -- e
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* privateExponent INTEGER, -- d
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* prime1 INTEGER, -- p
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* prime2 INTEGER, -- q
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* exponent1 INTEGER, -- d mod (p-1)
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* exponent2 INTEGER, -- d mod (q-1)
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* coefficient INTEGER -- (inverse of q) mod p
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* }
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*
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* Version ::= INTEGER
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*
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* The OID for the RSA key algorithm is: 1.2.840.113549.1.1.1
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*/
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var forge = require('./forge');
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require('./asn1');
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require('./jsbn');
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require('./oids');
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require('./pkcs1');
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require('./prime');
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require('./random');
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require('./util');
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if(typeof BigInteger === 'undefined') {
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var BigInteger = forge.jsbn.BigInteger;
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}
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// shortcut for asn.1 API
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var asn1 = forge.asn1;
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/*
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* RSA encryption and decryption, see RFC 2313.
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*/
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forge.pki = forge.pki || {};
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module.exports = forge.pki.rsa = forge.rsa = forge.rsa || {};
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var pki = forge.pki;
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// for finding primes, which are 30k+i for i = 1, 7, 11, 13, 17, 19, 23, 29
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var GCD_30_DELTA = [6, 4, 2, 4, 2, 4, 6, 2];
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// validator for a PrivateKeyInfo structure
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var privateKeyValidator = {
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// PrivateKeyInfo
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name: 'PrivateKeyInfo',
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tagClass: asn1.Class.UNIVERSAL,
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type: asn1.Type.SEQUENCE,
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constructed: true,
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value: [{
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// Version (INTEGER)
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name: 'PrivateKeyInfo.version',
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tagClass: asn1.Class.UNIVERSAL,
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type: asn1.Type.INTEGER,
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constructed: false,
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capture: 'privateKeyVersion'
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}, {
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// privateKeyAlgorithm
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name: 'PrivateKeyInfo.privateKeyAlgorithm',
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tagClass: asn1.Class.UNIVERSAL,
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type: asn1.Type.SEQUENCE,
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constructed: true,
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value: [{
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name: 'AlgorithmIdentifier.algorithm',
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tagClass: asn1.Class.UNIVERSAL,
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type: asn1.Type.OID,
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constructed: false,
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capture: 'privateKeyOid'
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}]
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}, {
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// PrivateKey
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name: 'PrivateKeyInfo',
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tagClass: asn1.Class.UNIVERSAL,
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type: asn1.Type.OCTETSTRING,
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constructed: false,
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capture: 'privateKey'
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}]
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};
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// validator for an RSA private key
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var rsaPrivateKeyValidator = {
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// RSAPrivateKey
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name: 'RSAPrivateKey',
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tagClass: asn1.Class.UNIVERSAL,
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type: asn1.Type.SEQUENCE,
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constructed: true,
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value: [{
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// Version (INTEGER)
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name: 'RSAPrivateKey.version',
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tagClass: asn1.Class.UNIVERSAL,
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type: asn1.Type.INTEGER,
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constructed: false,
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capture: 'privateKeyVersion'
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}, {
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// modulus (n)
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name: 'RSAPrivateKey.modulus',
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tagClass: asn1.Class.UNIVERSAL,
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type: asn1.Type.INTEGER,
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constructed: false,
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capture: 'privateKeyModulus'
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}, {
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// publicExponent (e)
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name: 'RSAPrivateKey.publicExponent',
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tagClass: asn1.Class.UNIVERSAL,
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type: asn1.Type.INTEGER,
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constructed: false,
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capture: 'privateKeyPublicExponent'
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}, {
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// privateExponent (d)
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name: 'RSAPrivateKey.privateExponent',
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tagClass: asn1.Class.UNIVERSAL,
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type: asn1.Type.INTEGER,
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constructed: false,
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capture: 'privateKeyPrivateExponent'
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}, {
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// prime1 (p)
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name: 'RSAPrivateKey.prime1',
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tagClass: asn1.Class.UNIVERSAL,
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type: asn1.Type.INTEGER,
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constructed: false,
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capture: 'privateKeyPrime1'
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}, {
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// prime2 (q)
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name: 'RSAPrivateKey.prime2',
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tagClass: asn1.Class.UNIVERSAL,
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type: asn1.Type.INTEGER,
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constructed: false,
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capture: 'privateKeyPrime2'
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}, {
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// exponent1 (d mod (p-1))
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name: 'RSAPrivateKey.exponent1',
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tagClass: asn1.Class.UNIVERSAL,
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type: asn1.Type.INTEGER,
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constructed: false,
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capture: 'privateKeyExponent1'
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}, {
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// exponent2 (d mod (q-1))
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name: 'RSAPrivateKey.exponent2',
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tagClass: asn1.Class.UNIVERSAL,
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type: asn1.Type.INTEGER,
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constructed: false,
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capture: 'privateKeyExponent2'
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}, {
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// coefficient ((inverse of q) mod p)
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name: 'RSAPrivateKey.coefficient',
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tagClass: asn1.Class.UNIVERSAL,
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type: asn1.Type.INTEGER,
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constructed: false,
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capture: 'privateKeyCoefficient'
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}]
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};
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// validator for an RSA public key
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var rsaPublicKeyValidator = {
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// RSAPublicKey
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name: 'RSAPublicKey',
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tagClass: asn1.Class.UNIVERSAL,
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type: asn1.Type.SEQUENCE,
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constructed: true,
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value: [{
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// modulus (n)
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name: 'RSAPublicKey.modulus',
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tagClass: asn1.Class.UNIVERSAL,
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type: asn1.Type.INTEGER,
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constructed: false,
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capture: 'publicKeyModulus'
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}, {
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// publicExponent (e)
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name: 'RSAPublicKey.exponent',
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tagClass: asn1.Class.UNIVERSAL,
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type: asn1.Type.INTEGER,
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constructed: false,
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capture: 'publicKeyExponent'
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}]
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};
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// validator for an SubjectPublicKeyInfo structure
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// Note: Currently only works with an RSA public key
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var publicKeyValidator = forge.pki.rsa.publicKeyValidator = {
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name: 'SubjectPublicKeyInfo',
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tagClass: asn1.Class.UNIVERSAL,
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type: asn1.Type.SEQUENCE,
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constructed: true,
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captureAsn1: 'subjectPublicKeyInfo',
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value: [{
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name: 'SubjectPublicKeyInfo.AlgorithmIdentifier',
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tagClass: asn1.Class.UNIVERSAL,
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type: asn1.Type.SEQUENCE,
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constructed: true,
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value: [{
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name: 'AlgorithmIdentifier.algorithm',
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tagClass: asn1.Class.UNIVERSAL,
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type: asn1.Type.OID,
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constructed: false,
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capture: 'publicKeyOid'
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}]
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}, {
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// subjectPublicKey
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name: 'SubjectPublicKeyInfo.subjectPublicKey',
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tagClass: asn1.Class.UNIVERSAL,
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type: asn1.Type.BITSTRING,
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constructed: false,
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value: [{
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// RSAPublicKey
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name: 'SubjectPublicKeyInfo.subjectPublicKey.RSAPublicKey',
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tagClass: asn1.Class.UNIVERSAL,
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type: asn1.Type.SEQUENCE,
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constructed: true,
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optional: true,
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captureAsn1: 'rsaPublicKey'
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}]
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}]
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};
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/**
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* Wrap digest in DigestInfo object.
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*
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* This function implements EMSA-PKCS1-v1_5-ENCODE as per RFC 3447.
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*
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* DigestInfo ::= SEQUENCE {
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* digestAlgorithm DigestAlgorithmIdentifier,
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* digest Digest
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* }
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*
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* DigestAlgorithmIdentifier ::= AlgorithmIdentifier
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* Digest ::= OCTET STRING
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*
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* @param md the message digest object with the hash to sign.
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*
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* @return the encoded message (ready for RSA encrytion)
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*/
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var emsaPkcs1v15encode = function(md) {
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// get the oid for the algorithm
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var oid;
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if(md.algorithm in pki.oids) {
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oid = pki.oids[md.algorithm];
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} else {
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var error = new Error('Unknown message digest algorithm.');
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error.algorithm = md.algorithm;
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throw error;
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}
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var oidBytes = asn1.oidToDer(oid).getBytes();
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// create the digest info
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var digestInfo = asn1.create(
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asn1.Class.UNIVERSAL, asn1.Type.SEQUENCE, true, []);
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var digestAlgorithm = asn1.create(
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asn1.Class.UNIVERSAL, asn1.Type.SEQUENCE, true, []);
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digestAlgorithm.value.push(asn1.create(
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asn1.Class.UNIVERSAL, asn1.Type.OID, false, oidBytes));
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digestAlgorithm.value.push(asn1.create(
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asn1.Class.UNIVERSAL, asn1.Type.NULL, false, ''));
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var digest = asn1.create(
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asn1.Class.UNIVERSAL, asn1.Type.OCTETSTRING,
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false, md.digest().getBytes());
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digestInfo.value.push(digestAlgorithm);
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digestInfo.value.push(digest);
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// encode digest info
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return asn1.toDer(digestInfo).getBytes();
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};
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/**
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* Performs x^c mod n (RSA encryption or decryption operation).
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*
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* @param x the number to raise and mod.
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* @param key the key to use.
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* @param pub true if the key is public, false if private.
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*
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* @return the result of x^c mod n.
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*/
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var _modPow = function(x, key, pub) {
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if(pub) {
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return x.modPow(key.e, key.n);
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}
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if(!key.p || !key.q) {
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// allow calculation without CRT params (slow)
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return x.modPow(key.d, key.n);
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}
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// pre-compute dP, dQ, and qInv if necessary
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if(!key.dP) {
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key.dP = key.d.mod(key.p.subtract(BigInteger.ONE));
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}
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if(!key.dQ) {
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key.dQ = key.d.mod(key.q.subtract(BigInteger.ONE));
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}
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if(!key.qInv) {
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key.qInv = key.q.modInverse(key.p);
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}
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/* Chinese remainder theorem (CRT) states:
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Suppose n1, n2, ..., nk are positive integers which are pairwise
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coprime (n1 and n2 have no common factors other than 1). For any
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integers x1, x2, ..., xk there exists an integer x solving the
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system of simultaneous congruences (where ~= means modularly
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congruent so a ~= b mod n means a mod n = b mod n):
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x ~= x1 mod n1
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x ~= x2 mod n2
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...
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x ~= xk mod nk
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This system of congruences has a single simultaneous solution x
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between 0 and n - 1. Furthermore, each xk solution and x itself
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is congruent modulo the product n = n1*n2*...*nk.
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So x1 mod n = x2 mod n = xk mod n = x mod n.
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The single simultaneous solution x can be solved with the following
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equation:
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x = sum(xi*ri*si) mod n where ri = n/ni and si = ri^-1 mod ni.
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Where x is less than n, xi = x mod ni.
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For RSA we are only concerned with k = 2. The modulus n = pq, where
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p and q are coprime. The RSA decryption algorithm is:
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y = x^d mod n
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Given the above:
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x1 = x^d mod p
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r1 = n/p = q
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s1 = q^-1 mod p
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x2 = x^d mod q
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r2 = n/q = p
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s2 = p^-1 mod q
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So y = (x1r1s1 + x2r2s2) mod n
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= ((x^d mod p)q(q^-1 mod p) + (x^d mod q)p(p^-1 mod q)) mod n
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According to Fermat's Little Theorem, if the modulus P is prime,
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for any integer A not evenly divisible by P, A^(P-1) ~= 1 mod P.
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Since A is not divisible by P it follows that if:
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N ~= M mod (P - 1), then A^N mod P = A^M mod P. Therefore:
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A^N mod P = A^(M mod (P - 1)) mod P. (The latter takes less effort
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to calculate). In order to calculate x^d mod p more quickly the
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exponent d mod (p - 1) is stored in the RSA private key (the same
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is done for x^d mod q). These values are referred to as dP and dQ
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respectively. Therefore we now have:
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y = ((x^dP mod p)q(q^-1 mod p) + (x^dQ mod q)p(p^-1 mod q)) mod n
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Since we'll be reducing x^dP by modulo p (same for q) we can also
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reduce x by p (and q respectively) before hand. Therefore, let
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xp = ((x mod p)^dP mod p), and
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xq = ((x mod q)^dQ mod q), yielding:
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y = (xp*q*(q^-1 mod p) + xq*p*(p^-1 mod q)) mod n
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This can be further reduced to a simple algorithm that only
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requires 1 inverse (the q inverse is used) to be used and stored.
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The algorithm is called Garner's algorithm. If qInv is the
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inverse of q, we simply calculate:
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y = (qInv*(xp - xq) mod p) * q + xq
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However, there are two further complications. First, we need to
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ensure that xp > xq to prevent signed BigIntegers from being used
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so we add p until this is true (since we will be mod'ing with
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p anyway). Then, there is a known timing attack on algorithms
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using the CRT. To mitigate this risk, "cryptographic blinding"
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should be used. This requires simply generating a random number r
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between 0 and n-1 and its inverse and multiplying x by r^e before
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calculating y and then multiplying y by r^-1 afterwards. Note that
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r must be coprime with n (gcd(r, n) === 1) in order to have an
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inverse.
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*/
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// cryptographic blinding
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var r;
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do {
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r = new BigInteger(
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forge.util.bytesToHex(forge.random.getBytes(key.n.bitLength() / 8)),
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16);
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} while(r.compareTo(key.n) >= 0 || !r.gcd(key.n).equals(BigInteger.ONE));
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x = x.multiply(r.modPow(key.e, key.n)).mod(key.n);
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// calculate xp and xq
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var xp = x.mod(key.p).modPow(key.dP, key.p);
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var xq = x.mod(key.q).modPow(key.dQ, key.q);
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// xp must be larger than xq to avoid signed bit usage
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while(xp.compareTo(xq) < 0) {
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xp = xp.add(key.p);
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}
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// do last step
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var y = xp.subtract(xq)
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.multiply(key.qInv).mod(key.p)
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.multiply(key.q).add(xq);
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// remove effect of random for cryptographic blinding
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y = y.multiply(r.modInverse(key.n)).mod(key.n);
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return y;
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};
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/**
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* NOTE: THIS METHOD IS DEPRECATED, use 'sign' on a private key object or
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* 'encrypt' on a public key object instead.
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*
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* Performs RSA encryption.
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*
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* The parameter bt controls whether to put padding bytes before the
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* message passed in. Set bt to either true or false to disable padding
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* completely (in order to handle e.g. EMSA-PSS encoding seperately before),
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* signaling whether the encryption operation is a public key operation
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* (i.e. encrypting data) or not, i.e. private key operation (data signing).
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*
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* For PKCS#1 v1.5 padding pass in the block type to use, i.e. either 0x01
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* (for signing) or 0x02 (for encryption). The key operation mode (private
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* or public) is derived from this flag in that case).
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*
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* @param m the message to encrypt as a byte string.
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* @param key the RSA key to use.
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* @param bt for PKCS#1 v1.5 padding, the block type to use
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* (0x01 for private key, 0x02 for public),
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* to disable padding: true = public key, false = private key.
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*
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* @return the encrypted bytes as a string.
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*/
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pki.rsa.encrypt = function(m, key, bt) {
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var pub = bt;
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var eb;
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// get the length of the modulus in bytes
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var k = Math.ceil(key.n.bitLength() / 8);
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if(bt !== false && bt !== true) {
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// legacy, default to PKCS#1 v1.5 padding
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pub = (bt === 0x02);
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eb = _encodePkcs1_v1_5(m, key, bt);
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} else {
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eb = forge.util.createBuffer();
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eb.putBytes(m);
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}
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// load encryption block as big integer 'x'
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// FIXME: hex conversion inefficient, get BigInteger w/byte strings
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var x = new BigInteger(eb.toHex(), 16);
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// do RSA encryption
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var y = _modPow(x, key, pub);
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|
// convert y into the encrypted data byte string, if y is shorter in
|
|
// bytes than k, then prepend zero bytes to fill up ed
|
|
// FIXME: hex conversion inefficient, get BigInteger w/byte strings
|
|
var yhex = y.toString(16);
|
|
var ed = forge.util.createBuffer();
|
|
var zeros = k - Math.ceil(yhex.length / 2);
|
|
while(zeros > 0) {
|
|
ed.putByte(0x00);
|
|
--zeros;
|
|
}
|
|
ed.putBytes(forge.util.hexToBytes(yhex));
|
|
return ed.getBytes();
|
|
};
|
|
|
|
/**
|
|
* NOTE: THIS METHOD IS DEPRECATED, use 'decrypt' on a private key object or
|
|
* 'verify' on a public key object instead.
|
|
*
|
|
* Performs RSA decryption.
|
|
*
|
|
* The parameter ml controls whether to apply PKCS#1 v1.5 padding
|
|
* or not. Set ml = false to disable padding removal completely
|
|
* (in order to handle e.g. EMSA-PSS later on) and simply pass back
|
|
* the RSA encryption block.
|
|
*
|
|
* @param ed the encrypted data to decrypt in as a byte string.
|
|
* @param key the RSA key to use.
|
|
* @param pub true for a public key operation, false for private.
|
|
* @param ml the message length, if known, false to disable padding.
|
|
*
|
|
* @return the decrypted message as a byte string.
|
|
*/
|
|
pki.rsa.decrypt = function(ed, key, pub, ml) {
|
|
// get the length of the modulus in bytes
|
|
var k = Math.ceil(key.n.bitLength() / 8);
|
|
|
|
// error if the length of the encrypted data ED is not k
|
|
if(ed.length !== k) {
|
|
var error = new Error('Encrypted message length is invalid.');
|
|
error.length = ed.length;
|
|
error.expected = k;
|
|
throw error;
|
|
}
|
|
|
|
// convert encrypted data into a big integer
|
|
// FIXME: hex conversion inefficient, get BigInteger w/byte strings
|
|
var y = new BigInteger(forge.util.createBuffer(ed).toHex(), 16);
|
|
|
|
// y must be less than the modulus or it wasn't the result of
|
|
// a previous mod operation (encryption) using that modulus
|
|
if(y.compareTo(key.n) >= 0) {
|
|
throw new Error('Encrypted message is invalid.');
|
|
}
|
|
|
|
// do RSA decryption
|
|
var x = _modPow(y, key, pub);
|
|
|
|
// create the encryption block, if x is shorter in bytes than k, then
|
|
// prepend zero bytes to fill up eb
|
|
// FIXME: hex conversion inefficient, get BigInteger w/byte strings
|
|
var xhex = x.toString(16);
|
|
var eb = forge.util.createBuffer();
|
|
var zeros = k - Math.ceil(xhex.length / 2);
|
|
while(zeros > 0) {
|
|
eb.putByte(0x00);
|
|
--zeros;
|
|
}
|
|
eb.putBytes(forge.util.hexToBytes(xhex));
|
|
|
|
if(ml !== false) {
|
|
// legacy, default to PKCS#1 v1.5 padding
|
|
return _decodePkcs1_v1_5(eb.getBytes(), key, pub);
|
|
}
|
|
|
|
// return message
|
|
return eb.getBytes();
|
|
};
|
|
|
|
/**
|
|
* Creates an RSA key-pair generation state object. It is used to allow
|
|
* key-generation to be performed in steps. It also allows for a UI to
|
|
* display progress updates.
|
|
*
|
|
* @param bits the size for the private key in bits, defaults to 2048.
|
|
* @param e the public exponent to use, defaults to 65537 (0x10001).
|
|
* @param [options] the options to use.
|
|
* prng a custom crypto-secure pseudo-random number generator to use,
|
|
* that must define "getBytesSync".
|
|
* algorithm the algorithm to use (default: 'PRIMEINC').
|
|
*
|
|
* @return the state object to use to generate the key-pair.
|
|
*/
|
|
pki.rsa.createKeyPairGenerationState = function(bits, e, options) {
|
|
// TODO: migrate step-based prime generation code to forge.prime
|
|
|
|
// set default bits
|
|
if(typeof(bits) === 'string') {
|
|
bits = parseInt(bits, 10);
|
|
}
|
|
bits = bits || 2048;
|
|
|
|
// create prng with api that matches BigInteger secure random
|
|
options = options || {};
|
|
var prng = options.prng || forge.random;
|
|
var rng = {
|
|
// x is an array to fill with bytes
|
|
nextBytes: function(x) {
|
|
var b = prng.getBytesSync(x.length);
|
|
for(var i = 0; i < x.length; ++i) {
|
|
x[i] = b.charCodeAt(i);
|
|
}
|
|
}
|
|
};
|
|
|
|
var algorithm = options.algorithm || 'PRIMEINC';
|
|
|
|
// create PRIMEINC algorithm state
|
|
var rval;
|
|
if(algorithm === 'PRIMEINC') {
|
|
rval = {
|
|
algorithm: algorithm,
|
|
state: 0,
|
|
bits: bits,
|
|
rng: rng,
|
|
eInt: e || 65537,
|
|
e: new BigInteger(null),
|
|
p: null,
|
|
q: null,
|
|
qBits: bits >> 1,
|
|
pBits: bits - (bits >> 1),
|
|
pqState: 0,
|
|
num: null,
|
|
keys: null
|
|
};
|
|
rval.e.fromInt(rval.eInt);
|
|
} else {
|
|
throw new Error('Invalid key generation algorithm: ' + algorithm);
|
|
}
|
|
|
|
return rval;
|
|
};
|
|
|
|
/**
|
|
* Attempts to runs the key-generation algorithm for at most n seconds
|
|
* (approximately) using the given state. When key-generation has completed,
|
|
* the keys will be stored in state.keys.
|
|
*
|
|
* To use this function to update a UI while generating a key or to prevent
|
|
* causing browser lockups/warnings, set "n" to a value other than 0. A
|
|
* simple pattern for generating a key and showing a progress indicator is:
|
|
*
|
|
* var state = pki.rsa.createKeyPairGenerationState(2048);
|
|
* var step = function() {
|
|
* // step key-generation, run algorithm for 100 ms, repeat
|
|
* if(!forge.pki.rsa.stepKeyPairGenerationState(state, 100)) {
|
|
* setTimeout(step, 1);
|
|
* } else {
|
|
* // key-generation complete
|
|
* // TODO: turn off progress indicator here
|
|
* // TODO: use the generated key-pair in "state.keys"
|
|
* }
|
|
* };
|
|
* // TODO: turn on progress indicator here
|
|
* setTimeout(step, 0);
|
|
*
|
|
* @param state the state to use.
|
|
* @param n the maximum number of milliseconds to run the algorithm for, 0
|
|
* to run the algorithm to completion.
|
|
*
|
|
* @return true if the key-generation completed, false if not.
|
|
*/
|
|
pki.rsa.stepKeyPairGenerationState = function(state, n) {
|
|
// set default algorithm if not set
|
|
if(!('algorithm' in state)) {
|
|
state.algorithm = 'PRIMEINC';
|
|
}
|
|
|
|
// TODO: migrate step-based prime generation code to forge.prime
|
|
// TODO: abstract as PRIMEINC algorithm
|
|
|
|
// do key generation (based on Tom Wu's rsa.js, see jsbn.js license)
|
|
// with some minor optimizations and designed to run in steps
|
|
|
|
// local state vars
|
|
var THIRTY = new BigInteger(null);
|
|
THIRTY.fromInt(30);
|
|
var deltaIdx = 0;
|
|
var op_or = function(x, y) { return x|y; };
|
|
|
|
// keep stepping until time limit is reached or done
|
|
var t1 = +new Date();
|
|
var t2;
|
|
var total = 0;
|
|
while(state.keys === null && (n <= 0 || total < n)) {
|
|
// generate p or q
|
|
if(state.state === 0) {
|
|
/* Note: All primes are of the form:
|
|
|
|
30k+i, for i < 30 and gcd(30, i)=1, where there are 8 values for i
|
|
|
|
When we generate a random number, we always align it at 30k + 1. Each
|
|
time the number is determined not to be prime we add to get to the
|
|
next 'i', eg: if the number was at 30k + 1 we add 6. */
|
|
var bits = (state.p === null) ? state.pBits : state.qBits;
|
|
var bits1 = bits - 1;
|
|
|
|
// get a random number
|
|
if(state.pqState === 0) {
|
|
state.num = new BigInteger(bits, state.rng);
|
|
// force MSB set
|
|
if(!state.num.testBit(bits1)) {
|
|
state.num.bitwiseTo(
|
|
BigInteger.ONE.shiftLeft(bits1), op_or, state.num);
|
|
}
|
|
// align number on 30k+1 boundary
|
|
state.num.dAddOffset(31 - state.num.mod(THIRTY).byteValue(), 0);
|
|
deltaIdx = 0;
|
|
|
|
++state.pqState;
|
|
} else if(state.pqState === 1) {
|
|
// try to make the number a prime
|
|
if(state.num.bitLength() > bits) {
|
|
// overflow, try again
|
|
state.pqState = 0;
|
|
// do primality test
|
|
} else if(state.num.isProbablePrime(
|
|
_getMillerRabinTests(state.num.bitLength()))) {
|
|
++state.pqState;
|
|
} else {
|
|
// get next potential prime
|
|
state.num.dAddOffset(GCD_30_DELTA[deltaIdx++ % 8], 0);
|
|
}
|
|
} else if(state.pqState === 2) {
|
|
// ensure number is coprime with e
|
|
state.pqState =
|
|
(state.num.subtract(BigInteger.ONE).gcd(state.e)
|
|
.compareTo(BigInteger.ONE) === 0) ? 3 : 0;
|
|
} else if(state.pqState === 3) {
|
|
// store p or q
|
|
state.pqState = 0;
|
|
if(state.p === null) {
|
|
state.p = state.num;
|
|
} else {
|
|
state.q = state.num;
|
|
}
|
|
|
|
// advance state if both p and q are ready
|
|
if(state.p !== null && state.q !== null) {
|
|
++state.state;
|
|
}
|
|
state.num = null;
|
|
}
|
|
} else if(state.state === 1) {
|
|
// ensure p is larger than q (swap them if not)
|
|
if(state.p.compareTo(state.q) < 0) {
|
|
state.num = state.p;
|
|
state.p = state.q;
|
|
state.q = state.num;
|
|
}
|
|
++state.state;
|
|
} else if(state.state === 2) {
|
|
// compute phi: (p - 1)(q - 1) (Euler's totient function)
|
|
state.p1 = state.p.subtract(BigInteger.ONE);
|
|
state.q1 = state.q.subtract(BigInteger.ONE);
|
|
state.phi = state.p1.multiply(state.q1);
|
|
++state.state;
|
|
} else if(state.state === 3) {
|
|
// ensure e and phi are coprime
|
|
if(state.phi.gcd(state.e).compareTo(BigInteger.ONE) === 0) {
|
|
// phi and e are coprime, advance
|
|
++state.state;
|
|
} else {
|
|
// phi and e aren't coprime, so generate a new p and q
|
|
state.p = null;
|
|
state.q = null;
|
|
state.state = 0;
|
|
}
|
|
} else if(state.state === 4) {
|
|
// create n, ensure n is has the right number of bits
|
|
state.n = state.p.multiply(state.q);
|
|
|
|
// ensure n is right number of bits
|
|
if(state.n.bitLength() === state.bits) {
|
|
// success, advance
|
|
++state.state;
|
|
} else {
|
|
// failed, get new q
|
|
state.q = null;
|
|
state.state = 0;
|
|
}
|
|
} else if(state.state === 5) {
|
|
// set keys
|
|
var d = state.e.modInverse(state.phi);
|
|
state.keys = {
|
|
privateKey: pki.rsa.setPrivateKey(
|
|
state.n, state.e, d, state.p, state.q,
|
|
d.mod(state.p1), d.mod(state.q1),
|
|
state.q.modInverse(state.p)),
|
|
publicKey: pki.rsa.setPublicKey(state.n, state.e)
|
|
};
|
|
}
|
|
|
|
// update timing
|
|
t2 = +new Date();
|
|
total += t2 - t1;
|
|
t1 = t2;
|
|
}
|
|
|
|
return state.keys !== null;
|
|
};
|
|
|
|
/**
|
|
* Generates an RSA public-private key pair in a single call.
|
|
*
|
|
* To generate a key-pair in steps (to allow for progress updates and to
|
|
* prevent blocking or warnings in slow browsers) then use the key-pair
|
|
* generation state functions.
|
|
*
|
|
* To generate a key-pair asynchronously (either through web-workers, if
|
|
* available, or by breaking up the work on the main thread), pass a
|
|
* callback function.
|
|
*
|
|
* @param [bits] the size for the private key in bits, defaults to 2048.
|
|
* @param [e] the public exponent to use, defaults to 65537.
|
|
* @param [options] options for key-pair generation, if given then 'bits'
|
|
* and 'e' must *not* be given:
|
|
* bits the size for the private key in bits, (default: 2048).
|
|
* e the public exponent to use, (default: 65537 (0x10001)).
|
|
* workerScript the worker script URL.
|
|
* workers the number of web workers (if supported) to use,
|
|
* (default: 2).
|
|
* workLoad the size of the work load, ie: number of possible prime
|
|
* numbers for each web worker to check per work assignment,
|
|
* (default: 100).
|
|
* prng a custom crypto-secure pseudo-random number generator to use,
|
|
* that must define "getBytesSync".
|
|
* algorithm the algorithm to use (default: 'PRIMEINC').
|
|
* @param [callback(err, keypair)] called once the operation completes.
|
|
*
|
|
* @return an object with privateKey and publicKey properties.
|
|
*/
|
|
pki.rsa.generateKeyPair = function(bits, e, options, callback) {
|
|
// (bits), (options), (callback)
|
|
if(arguments.length === 1) {
|
|
if(typeof bits === 'object') {
|
|
options = bits;
|
|
bits = undefined;
|
|
} else if(typeof bits === 'function') {
|
|
callback = bits;
|
|
bits = undefined;
|
|
}
|
|
} else if(arguments.length === 2) {
|
|
// (bits, e), (bits, options), (bits, callback), (options, callback)
|
|
if(typeof bits === 'number') {
|
|
if(typeof e === 'function') {
|
|
callback = e;
|
|
e = undefined;
|
|
} else if(typeof e !== 'number') {
|
|
options = e;
|
|
e = undefined;
|
|
}
|
|
} else {
|
|
options = bits;
|
|
callback = e;
|
|
bits = undefined;
|
|
e = undefined;
|
|
}
|
|
} else if(arguments.length === 3) {
|
|
// (bits, e, options), (bits, e, callback), (bits, options, callback)
|
|
if(typeof e === 'number') {
|
|
if(typeof options === 'function') {
|
|
callback = options;
|
|
options = undefined;
|
|
}
|
|
} else {
|
|
callback = options;
|
|
options = e;
|
|
e = undefined;
|
|
}
|
|
}
|
|
options = options || {};
|
|
if(bits === undefined) {
|
|
bits = options.bits || 2048;
|
|
}
|
|
if(e === undefined) {
|
|
e = options.e || 0x10001;
|
|
}
|
|
|
|
// if native code is permitted and a callback is given, use native
|
|
// key generation code if available and if parameters are acceptable
|
|
if(!forge.options.usePureJavaScript && callback &&
|
|
bits >= 256 && bits <= 16384 && (e === 0x10001 || e === 3)) {
|
|
if(_detectSubtleCrypto('generateKey') && _detectSubtleCrypto('exportKey')) {
|
|
// use standard native generateKey
|
|
return window.crypto.subtle.generateKey({
|
|
name: 'RSASSA-PKCS1-v1_5',
|
|
modulusLength: bits,
|
|
publicExponent: _intToUint8Array(e),
|
|
hash: {name: 'SHA-256'}
|
|
}, true /* key can be exported*/, ['sign', 'verify'])
|
|
.then(function(pair) {
|
|
return window.crypto.subtle.exportKey('pkcs8', pair.privateKey);
|
|
// avoiding catch(function(err) {...}) to support IE <= 8
|
|
}).then(undefined, function(err) {
|
|
callback(err);
|
|
}).then(function(pkcs8) {
|
|
if(pkcs8) {
|
|
var privateKey = pki.privateKeyFromAsn1(
|
|
asn1.fromDer(forge.util.createBuffer(pkcs8)));
|
|
callback(null, {
|
|
privateKey: privateKey,
|
|
publicKey: pki.setRsaPublicKey(privateKey.n, privateKey.e)
|
|
});
|
|
}
|
|
});
|
|
}
|
|
if(_detectSubtleMsCrypto('generateKey') &&
|
|
_detectSubtleMsCrypto('exportKey')) {
|
|
var genOp = window.msCrypto.subtle.generateKey({
|
|
name: 'RSASSA-PKCS1-v1_5',
|
|
modulusLength: bits,
|
|
publicExponent: _intToUint8Array(e),
|
|
hash: {name: 'SHA-256'}
|
|
}, true /* key can be exported*/, ['sign', 'verify']);
|
|
genOp.oncomplete = function(e) {
|
|
var pair = e.target.result;
|
|
var exportOp = window.msCrypto.subtle.exportKey(
|
|
'pkcs8', pair.privateKey);
|
|
exportOp.oncomplete = function(e) {
|
|
var pkcs8 = e.target.result;
|
|
var privateKey = pki.privateKeyFromAsn1(
|
|
asn1.fromDer(forge.util.createBuffer(pkcs8)));
|
|
callback(null, {
|
|
privateKey: privateKey,
|
|
publicKey: pki.setRsaPublicKey(privateKey.n, privateKey.e)
|
|
});
|
|
};
|
|
exportOp.onerror = function(err) {
|
|
callback(err);
|
|
};
|
|
};
|
|
genOp.onerror = function(err) {
|
|
callback(err);
|
|
};
|
|
return;
|
|
}
|
|
}
|
|
|
|
// use JavaScript implementation
|
|
var state = pki.rsa.createKeyPairGenerationState(bits, e, options);
|
|
if(!callback) {
|
|
pki.rsa.stepKeyPairGenerationState(state, 0);
|
|
return state.keys;
|
|
}
|
|
_generateKeyPair(state, options, callback);
|
|
};
|
|
|
|
/**
|
|
* Sets an RSA public key from BigIntegers modulus and exponent.
|
|
*
|
|
* @param n the modulus.
|
|
* @param e the exponent.
|
|
*
|
|
* @return the public key.
|
|
*/
|
|
pki.setRsaPublicKey = pki.rsa.setPublicKey = function(n, e) {
|
|
var key = {
|
|
n: n,
|
|
e: e
|
|
};
|
|
|
|
/**
|
|
* Encrypts the given data with this public key. Newer applications
|
|
* should use the 'RSA-OAEP' decryption scheme, 'RSAES-PKCS1-V1_5' is for
|
|
* legacy applications.
|
|
*
|
|
* @param data the byte string to encrypt.
|
|
* @param scheme the encryption scheme to use:
|
|
* 'RSAES-PKCS1-V1_5' (default),
|
|
* 'RSA-OAEP',
|
|
* 'RAW', 'NONE', or null to perform raw RSA encryption,
|
|
* an object with an 'encode' property set to a function
|
|
* with the signature 'function(data, key)' that returns
|
|
* a binary-encoded string representing the encoded data.
|
|
* @param schemeOptions any scheme-specific options.
|
|
*
|
|
* @return the encrypted byte string.
|
|
*/
|
|
key.encrypt = function(data, scheme, schemeOptions) {
|
|
if(typeof scheme === 'string') {
|
|
scheme = scheme.toUpperCase();
|
|
} else if(scheme === undefined) {
|
|
scheme = 'RSAES-PKCS1-V1_5';
|
|
}
|
|
|
|
if(scheme === 'RSAES-PKCS1-V1_5') {
|
|
scheme = {
|
|
encode: function(m, key, pub) {
|
|
return _encodePkcs1_v1_5(m, key, 0x02).getBytes();
|
|
}
|
|
};
|
|
} else if(scheme === 'RSA-OAEP' || scheme === 'RSAES-OAEP') {
|
|
scheme = {
|
|
encode: function(m, key) {
|
|
return forge.pkcs1.encode_rsa_oaep(key, m, schemeOptions);
|
|
}
|
|
};
|
|
} else if(['RAW', 'NONE', 'NULL', null].indexOf(scheme) !== -1) {
|
|
scheme = { encode: function(e) { return e; } };
|
|
} else if(typeof scheme === 'string') {
|
|
throw new Error('Unsupported encryption scheme: "' + scheme + '".');
|
|
}
|
|
|
|
// do scheme-based encoding then rsa encryption
|
|
var e = scheme.encode(data, key, true);
|
|
return pki.rsa.encrypt(e, key, true);
|
|
};
|
|
|
|
/**
|
|
* Verifies the given signature against the given digest.
|
|
*
|
|
* PKCS#1 supports multiple (currently two) signature schemes:
|
|
* RSASSA-PKCS1-V1_5 and RSASSA-PSS.
|
|
*
|
|
* By default this implementation uses the "old scheme", i.e.
|
|
* RSASSA-PKCS1-V1_5, in which case once RSA-decrypted, the
|
|
* signature is an OCTET STRING that holds a DigestInfo.
|
|
*
|
|
* DigestInfo ::= SEQUENCE {
|
|
* digestAlgorithm DigestAlgorithmIdentifier,
|
|
* digest Digest
|
|
* }
|
|
* DigestAlgorithmIdentifier ::= AlgorithmIdentifier
|
|
* Digest ::= OCTET STRING
|
|
*
|
|
* To perform PSS signature verification, provide an instance
|
|
* of Forge PSS object as the scheme parameter.
|
|
*
|
|
* @param digest the message digest hash to compare against the signature,
|
|
* as a binary-encoded string.
|
|
* @param signature the signature to verify, as a binary-encoded string.
|
|
* @param scheme signature verification scheme to use:
|
|
* 'RSASSA-PKCS1-V1_5' or undefined for RSASSA PKCS#1 v1.5,
|
|
* a Forge PSS object for RSASSA-PSS,
|
|
* 'NONE' or null for none, DigestInfo will not be expected, but
|
|
* PKCS#1 v1.5 padding will still be used.
|
|
*
|
|
* @return true if the signature was verified, false if not.
|
|
*/
|
|
key.verify = function(digest, signature, scheme) {
|
|
if(typeof scheme === 'string') {
|
|
scheme = scheme.toUpperCase();
|
|
} else if(scheme === undefined) {
|
|
scheme = 'RSASSA-PKCS1-V1_5';
|
|
}
|
|
|
|
if(scheme === 'RSASSA-PKCS1-V1_5') {
|
|
scheme = {
|
|
verify: function(digest, d) {
|
|
// remove padding
|
|
d = _decodePkcs1_v1_5(d, key, true);
|
|
// d is ASN.1 BER-encoded DigestInfo
|
|
var obj = asn1.fromDer(d);
|
|
// compare the given digest to the decrypted one
|
|
return digest === obj.value[1].value;
|
|
}
|
|
};
|
|
} else if(scheme === 'NONE' || scheme === 'NULL' || scheme === null) {
|
|
scheme = {
|
|
verify: function(digest, d) {
|
|
// remove padding
|
|
d = _decodePkcs1_v1_5(d, key, true);
|
|
return digest === d;
|
|
}
|
|
};
|
|
}
|
|
|
|
// do rsa decryption w/o any decoding, then verify -- which does decoding
|
|
var d = pki.rsa.decrypt(signature, key, true, false);
|
|
return scheme.verify(digest, d, key.n.bitLength());
|
|
};
|
|
|
|
return key;
|
|
};
|
|
|
|
/**
|
|
* Sets an RSA private key from BigIntegers modulus, exponent, primes,
|
|
* prime exponents, and modular multiplicative inverse.
|
|
*
|
|
* @param n the modulus.
|
|
* @param e the public exponent.
|
|
* @param d the private exponent ((inverse of e) mod n).
|
|
* @param p the first prime.
|
|
* @param q the second prime.
|
|
* @param dP exponent1 (d mod (p-1)).
|
|
* @param dQ exponent2 (d mod (q-1)).
|
|
* @param qInv ((inverse of q) mod p)
|
|
*
|
|
* @return the private key.
|
|
*/
|
|
pki.setRsaPrivateKey = pki.rsa.setPrivateKey = function(
|
|
n, e, d, p, q, dP, dQ, qInv) {
|
|
var key = {
|
|
n: n,
|
|
e: e,
|
|
d: d,
|
|
p: p,
|
|
q: q,
|
|
dP: dP,
|
|
dQ: dQ,
|
|
qInv: qInv
|
|
};
|
|
|
|
/**
|
|
* Decrypts the given data with this private key. The decryption scheme
|
|
* must match the one used to encrypt the data.
|
|
*
|
|
* @param data the byte string to decrypt.
|
|
* @param scheme the decryption scheme to use:
|
|
* 'RSAES-PKCS1-V1_5' (default),
|
|
* 'RSA-OAEP',
|
|
* 'RAW', 'NONE', or null to perform raw RSA decryption.
|
|
* @param schemeOptions any scheme-specific options.
|
|
*
|
|
* @return the decrypted byte string.
|
|
*/
|
|
key.decrypt = function(data, scheme, schemeOptions) {
|
|
if(typeof scheme === 'string') {
|
|
scheme = scheme.toUpperCase();
|
|
} else if(scheme === undefined) {
|
|
scheme = 'RSAES-PKCS1-V1_5';
|
|
}
|
|
|
|
// do rsa decryption w/o any decoding
|
|
var d = pki.rsa.decrypt(data, key, false, false);
|
|
|
|
if(scheme === 'RSAES-PKCS1-V1_5') {
|
|
scheme = { decode: _decodePkcs1_v1_5 };
|
|
} else if(scheme === 'RSA-OAEP' || scheme === 'RSAES-OAEP') {
|
|
scheme = {
|
|
decode: function(d, key) {
|
|
return forge.pkcs1.decode_rsa_oaep(key, d, schemeOptions);
|
|
}
|
|
};
|
|
} else if(['RAW', 'NONE', 'NULL', null].indexOf(scheme) !== -1) {
|
|
scheme = { decode: function(d) { return d; } };
|
|
} else {
|
|
throw new Error('Unsupported encryption scheme: "' + scheme + '".');
|
|
}
|
|
|
|
// decode according to scheme
|
|
return scheme.decode(d, key, false);
|
|
};
|
|
|
|
/**
|
|
* Signs the given digest, producing a signature.
|
|
*
|
|
* PKCS#1 supports multiple (currently two) signature schemes:
|
|
* RSASSA-PKCS1-V1_5 and RSASSA-PSS.
|
|
*
|
|
* By default this implementation uses the "old scheme", i.e.
|
|
* RSASSA-PKCS1-V1_5. In order to generate a PSS signature, provide
|
|
* an instance of Forge PSS object as the scheme parameter.
|
|
*
|
|
* @param md the message digest object with the hash to sign.
|
|
* @param scheme the signature scheme to use:
|
|
* 'RSASSA-PKCS1-V1_5' or undefined for RSASSA PKCS#1 v1.5,
|
|
* a Forge PSS object for RSASSA-PSS,
|
|
* 'NONE' or null for none, DigestInfo will not be used but
|
|
* PKCS#1 v1.5 padding will still be used.
|
|
*
|
|
* @return the signature as a byte string.
|
|
*/
|
|
key.sign = function(md, scheme) {
|
|
/* Note: The internal implementation of RSA operations is being
|
|
transitioned away from a PKCS#1 v1.5 hard-coded scheme. Some legacy
|
|
code like the use of an encoding block identifier 'bt' will eventually
|
|
be removed. */
|
|
|
|
// private key operation
|
|
var bt = false;
|
|
|
|
if(typeof scheme === 'string') {
|
|
scheme = scheme.toUpperCase();
|
|
}
|
|
|
|
if(scheme === undefined || scheme === 'RSASSA-PKCS1-V1_5') {
|
|
scheme = { encode: emsaPkcs1v15encode };
|
|
bt = 0x01;
|
|
} else if(scheme === 'NONE' || scheme === 'NULL' || scheme === null) {
|
|
scheme = { encode: function() { return md; } };
|
|
bt = 0x01;
|
|
}
|
|
|
|
// encode and then encrypt
|
|
var d = scheme.encode(md, key.n.bitLength());
|
|
return pki.rsa.encrypt(d, key, bt);
|
|
};
|
|
|
|
return key;
|
|
};
|
|
|
|
/**
|
|
* Wraps an RSAPrivateKey ASN.1 object in an ASN.1 PrivateKeyInfo object.
|
|
*
|
|
* @param rsaKey the ASN.1 RSAPrivateKey.
|
|
*
|
|
* @return the ASN.1 PrivateKeyInfo.
|
|
*/
|
|
pki.wrapRsaPrivateKey = function(rsaKey) {
|
|
// PrivateKeyInfo
|
|
return asn1.create(asn1.Class.UNIVERSAL, asn1.Type.SEQUENCE, true, [
|
|
// version (0)
|
|
asn1.create(asn1.Class.UNIVERSAL, asn1.Type.INTEGER, false,
|
|
asn1.integerToDer(0).getBytes()),
|
|
// privateKeyAlgorithm
|
|
asn1.create(asn1.Class.UNIVERSAL, asn1.Type.SEQUENCE, true, [
|
|
asn1.create(
|
|
asn1.Class.UNIVERSAL, asn1.Type.OID, false,
|
|
asn1.oidToDer(pki.oids.rsaEncryption).getBytes()),
|
|
asn1.create(asn1.Class.UNIVERSAL, asn1.Type.NULL, false, '')
|
|
]),
|
|
// PrivateKey
|
|
asn1.create(asn1.Class.UNIVERSAL, asn1.Type.OCTETSTRING, false,
|
|
asn1.toDer(rsaKey).getBytes())
|
|
]);
|
|
};
|
|
|
|
/**
|
|
* Converts a private key from an ASN.1 object.
|
|
*
|
|
* @param obj the ASN.1 representation of a PrivateKeyInfo containing an
|
|
* RSAPrivateKey or an RSAPrivateKey.
|
|
*
|
|
* @return the private key.
|
|
*/
|
|
pki.privateKeyFromAsn1 = function(obj) {
|
|
// get PrivateKeyInfo
|
|
var capture = {};
|
|
var errors = [];
|
|
if(asn1.validate(obj, privateKeyValidator, capture, errors)) {
|
|
obj = asn1.fromDer(forge.util.createBuffer(capture.privateKey));
|
|
}
|
|
|
|
// get RSAPrivateKey
|
|
capture = {};
|
|
errors = [];
|
|
if(!asn1.validate(obj, rsaPrivateKeyValidator, capture, errors)) {
|
|
var error = new Error('Cannot read private key. ' +
|
|
'ASN.1 object does not contain an RSAPrivateKey.');
|
|
error.errors = errors;
|
|
throw error;
|
|
}
|
|
|
|
// Note: Version is currently ignored.
|
|
// capture.privateKeyVersion
|
|
// FIXME: inefficient, get a BigInteger that uses byte strings
|
|
var n, e, d, p, q, dP, dQ, qInv;
|
|
n = forge.util.createBuffer(capture.privateKeyModulus).toHex();
|
|
e = forge.util.createBuffer(capture.privateKeyPublicExponent).toHex();
|
|
d = forge.util.createBuffer(capture.privateKeyPrivateExponent).toHex();
|
|
p = forge.util.createBuffer(capture.privateKeyPrime1).toHex();
|
|
q = forge.util.createBuffer(capture.privateKeyPrime2).toHex();
|
|
dP = forge.util.createBuffer(capture.privateKeyExponent1).toHex();
|
|
dQ = forge.util.createBuffer(capture.privateKeyExponent2).toHex();
|
|
qInv = forge.util.createBuffer(capture.privateKeyCoefficient).toHex();
|
|
|
|
// set private key
|
|
return pki.setRsaPrivateKey(
|
|
new BigInteger(n, 16),
|
|
new BigInteger(e, 16),
|
|
new BigInteger(d, 16),
|
|
new BigInteger(p, 16),
|
|
new BigInteger(q, 16),
|
|
new BigInteger(dP, 16),
|
|
new BigInteger(dQ, 16),
|
|
new BigInteger(qInv, 16));
|
|
};
|
|
|
|
/**
|
|
* Converts a private key to an ASN.1 RSAPrivateKey.
|
|
*
|
|
* @param key the private key.
|
|
*
|
|
* @return the ASN.1 representation of an RSAPrivateKey.
|
|
*/
|
|
pki.privateKeyToAsn1 = pki.privateKeyToRSAPrivateKey = function(key) {
|
|
// RSAPrivateKey
|
|
return asn1.create(asn1.Class.UNIVERSAL, asn1.Type.SEQUENCE, true, [
|
|
// version (0 = only 2 primes, 1 multiple primes)
|
|
asn1.create(asn1.Class.UNIVERSAL, asn1.Type.INTEGER, false,
|
|
asn1.integerToDer(0).getBytes()),
|
|
// modulus (n)
|
|
asn1.create(asn1.Class.UNIVERSAL, asn1.Type.INTEGER, false,
|
|
_bnToBytes(key.n)),
|
|
// publicExponent (e)
|
|
asn1.create(asn1.Class.UNIVERSAL, asn1.Type.INTEGER, false,
|
|
_bnToBytes(key.e)),
|
|
// privateExponent (d)
|
|
asn1.create(asn1.Class.UNIVERSAL, asn1.Type.INTEGER, false,
|
|
_bnToBytes(key.d)),
|
|
// privateKeyPrime1 (p)
|
|
asn1.create(asn1.Class.UNIVERSAL, asn1.Type.INTEGER, false,
|
|
_bnToBytes(key.p)),
|
|
// privateKeyPrime2 (q)
|
|
asn1.create(asn1.Class.UNIVERSAL, asn1.Type.INTEGER, false,
|
|
_bnToBytes(key.q)),
|
|
// privateKeyExponent1 (dP)
|
|
asn1.create(asn1.Class.UNIVERSAL, asn1.Type.INTEGER, false,
|
|
_bnToBytes(key.dP)),
|
|
// privateKeyExponent2 (dQ)
|
|
asn1.create(asn1.Class.UNIVERSAL, asn1.Type.INTEGER, false,
|
|
_bnToBytes(key.dQ)),
|
|
// coefficient (qInv)
|
|
asn1.create(asn1.Class.UNIVERSAL, asn1.Type.INTEGER, false,
|
|
_bnToBytes(key.qInv))
|
|
]);
|
|
};
|
|
|
|
/**
|
|
* Converts a public key from an ASN.1 SubjectPublicKeyInfo or RSAPublicKey.
|
|
*
|
|
* @param obj the asn1 representation of a SubjectPublicKeyInfo or RSAPublicKey.
|
|
*
|
|
* @return the public key.
|
|
*/
|
|
pki.publicKeyFromAsn1 = function(obj) {
|
|
// get SubjectPublicKeyInfo
|
|
var capture = {};
|
|
var errors = [];
|
|
if(asn1.validate(obj, publicKeyValidator, capture, errors)) {
|
|
// get oid
|
|
var oid = asn1.derToOid(capture.publicKeyOid);
|
|
if(oid !== pki.oids.rsaEncryption) {
|
|
var error = new Error('Cannot read public key. Unknown OID.');
|
|
error.oid = oid;
|
|
throw error;
|
|
}
|
|
obj = capture.rsaPublicKey;
|
|
}
|
|
|
|
// get RSA params
|
|
errors = [];
|
|
if(!asn1.validate(obj, rsaPublicKeyValidator, capture, errors)) {
|
|
var error = new Error('Cannot read public key. ' +
|
|
'ASN.1 object does not contain an RSAPublicKey.');
|
|
error.errors = errors;
|
|
throw error;
|
|
}
|
|
|
|
// FIXME: inefficient, get a BigInteger that uses byte strings
|
|
var n = forge.util.createBuffer(capture.publicKeyModulus).toHex();
|
|
var e = forge.util.createBuffer(capture.publicKeyExponent).toHex();
|
|
|
|
// set public key
|
|
return pki.setRsaPublicKey(
|
|
new BigInteger(n, 16),
|
|
new BigInteger(e, 16));
|
|
};
|
|
|
|
/**
|
|
* Converts a public key to an ASN.1 SubjectPublicKeyInfo.
|
|
*
|
|
* @param key the public key.
|
|
*
|
|
* @return the asn1 representation of a SubjectPublicKeyInfo.
|
|
*/
|
|
pki.publicKeyToAsn1 = pki.publicKeyToSubjectPublicKeyInfo = function(key) {
|
|
// SubjectPublicKeyInfo
|
|
return asn1.create(asn1.Class.UNIVERSAL, asn1.Type.SEQUENCE, true, [
|
|
// AlgorithmIdentifier
|
|
asn1.create(asn1.Class.UNIVERSAL, asn1.Type.SEQUENCE, true, [
|
|
// algorithm
|
|
asn1.create(asn1.Class.UNIVERSAL, asn1.Type.OID, false,
|
|
asn1.oidToDer(pki.oids.rsaEncryption).getBytes()),
|
|
// parameters (null)
|
|
asn1.create(asn1.Class.UNIVERSAL, asn1.Type.NULL, false, '')
|
|
]),
|
|
// subjectPublicKey
|
|
asn1.create(asn1.Class.UNIVERSAL, asn1.Type.BITSTRING, false, [
|
|
pki.publicKeyToRSAPublicKey(key)
|
|
])
|
|
]);
|
|
};
|
|
|
|
/**
|
|
* Converts a public key to an ASN.1 RSAPublicKey.
|
|
*
|
|
* @param key the public key.
|
|
*
|
|
* @return the asn1 representation of a RSAPublicKey.
|
|
*/
|
|
pki.publicKeyToRSAPublicKey = function(key) {
|
|
// RSAPublicKey
|
|
return asn1.create(asn1.Class.UNIVERSAL, asn1.Type.SEQUENCE, true, [
|
|
// modulus (n)
|
|
asn1.create(asn1.Class.UNIVERSAL, asn1.Type.INTEGER, false,
|
|
_bnToBytes(key.n)),
|
|
// publicExponent (e)
|
|
asn1.create(asn1.Class.UNIVERSAL, asn1.Type.INTEGER, false,
|
|
_bnToBytes(key.e))
|
|
]);
|
|
};
|
|
|
|
/**
|
|
* Encodes a message using PKCS#1 v1.5 padding.
|
|
*
|
|
* @param m the message to encode.
|
|
* @param key the RSA key to use.
|
|
* @param bt the block type to use, i.e. either 0x01 (for signing) or 0x02
|
|
* (for encryption).
|
|
*
|
|
* @return the padded byte buffer.
|
|
*/
|
|
function _encodePkcs1_v1_5(m, key, bt) {
|
|
var eb = forge.util.createBuffer();
|
|
|
|
// get the length of the modulus in bytes
|
|
var k = Math.ceil(key.n.bitLength() / 8);
|
|
|
|
/* use PKCS#1 v1.5 padding */
|
|
if(m.length > (k - 11)) {
|
|
var error = new Error('Message is too long for PKCS#1 v1.5 padding.');
|
|
error.length = m.length;
|
|
error.max = k - 11;
|
|
throw error;
|
|
}
|
|
|
|
/* A block type BT, a padding string PS, and the data D shall be
|
|
formatted into an octet string EB, the encryption block:
|
|
|
|
EB = 00 || BT || PS || 00 || D
|
|
|
|
The block type BT shall be a single octet indicating the structure of
|
|
the encryption block. For this version of the document it shall have
|
|
value 00, 01, or 02. For a private-key operation, the block type
|
|
shall be 00 or 01. For a public-key operation, it shall be 02.
|
|
|
|
The padding string PS shall consist of k-3-||D|| octets. For block
|
|
type 00, the octets shall have value 00; for block type 01, they
|
|
shall have value FF; and for block type 02, they shall be
|
|
pseudorandomly generated and nonzero. This makes the length of the
|
|
encryption block EB equal to k. */
|
|
|
|
// build the encryption block
|
|
eb.putByte(0x00);
|
|
eb.putByte(bt);
|
|
|
|
// create the padding
|
|
var padNum = k - 3 - m.length;
|
|
var padByte;
|
|
// private key op
|
|
if(bt === 0x00 || bt === 0x01) {
|
|
padByte = (bt === 0x00) ? 0x00 : 0xFF;
|
|
for(var i = 0; i < padNum; ++i) {
|
|
eb.putByte(padByte);
|
|
}
|
|
} else {
|
|
// public key op
|
|
// pad with random non-zero values
|
|
while(padNum > 0) {
|
|
var numZeros = 0;
|
|
var padBytes = forge.random.getBytes(padNum);
|
|
for(var i = 0; i < padNum; ++i) {
|
|
padByte = padBytes.charCodeAt(i);
|
|
if(padByte === 0) {
|
|
++numZeros;
|
|
} else {
|
|
eb.putByte(padByte);
|
|
}
|
|
}
|
|
padNum = numZeros;
|
|
}
|
|
}
|
|
|
|
// zero followed by message
|
|
eb.putByte(0x00);
|
|
eb.putBytes(m);
|
|
|
|
return eb;
|
|
}
|
|
|
|
/**
|
|
* Decodes a message using PKCS#1 v1.5 padding.
|
|
*
|
|
* @param em the message to decode.
|
|
* @param key the RSA key to use.
|
|
* @param pub true if the key is a public key, false if it is private.
|
|
* @param ml the message length, if specified.
|
|
*
|
|
* @return the decoded bytes.
|
|
*/
|
|
function _decodePkcs1_v1_5(em, key, pub, ml) {
|
|
// get the length of the modulus in bytes
|
|
var k = Math.ceil(key.n.bitLength() / 8);
|
|
|
|
/* It is an error if any of the following conditions occurs:
|
|
|
|
1. The encryption block EB cannot be parsed unambiguously.
|
|
2. The padding string PS consists of fewer than eight octets
|
|
or is inconsisent with the block type BT.
|
|
3. The decryption process is a public-key operation and the block
|
|
type BT is not 00 or 01, or the decryption process is a
|
|
private-key operation and the block type is not 02.
|
|
*/
|
|
|
|
// parse the encryption block
|
|
var eb = forge.util.createBuffer(em);
|
|
var first = eb.getByte();
|
|
var bt = eb.getByte();
|
|
if(first !== 0x00 ||
|
|
(pub && bt !== 0x00 && bt !== 0x01) ||
|
|
(!pub && bt != 0x02) ||
|
|
(pub && bt === 0x00 && typeof(ml) === 'undefined')) {
|
|
throw new Error('Encryption block is invalid.');
|
|
}
|
|
|
|
var padNum = 0;
|
|
if(bt === 0x00) {
|
|
// check all padding bytes for 0x00
|
|
padNum = k - 3 - ml;
|
|
for(var i = 0; i < padNum; ++i) {
|
|
if(eb.getByte() !== 0x00) {
|
|
throw new Error('Encryption block is invalid.');
|
|
}
|
|
}
|
|
} else if(bt === 0x01) {
|
|
// find the first byte that isn't 0xFF, should be after all padding
|
|
padNum = 0;
|
|
while(eb.length() > 1) {
|
|
if(eb.getByte() !== 0xFF) {
|
|
--eb.read;
|
|
break;
|
|
}
|
|
++padNum;
|
|
}
|
|
} else if(bt === 0x02) {
|
|
// look for 0x00 byte
|
|
padNum = 0;
|
|
while(eb.length() > 1) {
|
|
if(eb.getByte() === 0x00) {
|
|
--eb.read;
|
|
break;
|
|
}
|
|
++padNum;
|
|
}
|
|
}
|
|
|
|
// zero must be 0x00 and padNum must be (k - 3 - message length)
|
|
var zero = eb.getByte();
|
|
if(zero !== 0x00 || padNum !== (k - 3 - eb.length())) {
|
|
throw new Error('Encryption block is invalid.');
|
|
}
|
|
|
|
return eb.getBytes();
|
|
}
|
|
|
|
/**
|
|
* Runs the key-generation algorithm asynchronously, either in the background
|
|
* via Web Workers, or using the main thread and setImmediate.
|
|
*
|
|
* @param state the key-pair generation state.
|
|
* @param [options] options for key-pair generation:
|
|
* workerScript the worker script URL.
|
|
* workers the number of web workers (if supported) to use,
|
|
* (default: 2, -1 to use estimated cores minus one).
|
|
* workLoad the size of the work load, ie: number of possible prime
|
|
* numbers for each web worker to check per work assignment,
|
|
* (default: 100).
|
|
* @param callback(err, keypair) called once the operation completes.
|
|
*/
|
|
function _generateKeyPair(state, options, callback) {
|
|
if(typeof options === 'function') {
|
|
callback = options;
|
|
options = {};
|
|
}
|
|
options = options || {};
|
|
|
|
var opts = {
|
|
algorithm: {
|
|
name: options.algorithm || 'PRIMEINC',
|
|
options: {
|
|
workers: options.workers || 2,
|
|
workLoad: options.workLoad || 100,
|
|
workerScript: options.workerScript
|
|
}
|
|
}
|
|
};
|
|
if('prng' in options) {
|
|
opts.prng = options.prng;
|
|
}
|
|
|
|
generate();
|
|
|
|
function generate() {
|
|
// find p and then q (done in series to simplify)
|
|
getPrime(state.pBits, function(err, num) {
|
|
if(err) {
|
|
return callback(err);
|
|
}
|
|
state.p = num;
|
|
if(state.q !== null) {
|
|
return finish(err, state.q);
|
|
}
|
|
getPrime(state.qBits, finish);
|
|
});
|
|
}
|
|
|
|
function getPrime(bits, callback) {
|
|
forge.prime.generateProbablePrime(bits, opts, callback);
|
|
}
|
|
|
|
function finish(err, num) {
|
|
if(err) {
|
|
return callback(err);
|
|
}
|
|
|
|
// set q
|
|
state.q = num;
|
|
|
|
// ensure p is larger than q (swap them if not)
|
|
if(state.p.compareTo(state.q) < 0) {
|
|
var tmp = state.p;
|
|
state.p = state.q;
|
|
state.q = tmp;
|
|
}
|
|
|
|
// ensure p is coprime with e
|
|
if(state.p.subtract(BigInteger.ONE).gcd(state.e)
|
|
.compareTo(BigInteger.ONE) !== 0) {
|
|
state.p = null;
|
|
generate();
|
|
return;
|
|
}
|
|
|
|
// ensure q is coprime with e
|
|
if(state.q.subtract(BigInteger.ONE).gcd(state.e)
|
|
.compareTo(BigInteger.ONE) !== 0) {
|
|
state.q = null;
|
|
getPrime(state.qBits, finish);
|
|
return;
|
|
}
|
|
|
|
// compute phi: (p - 1)(q - 1) (Euler's totient function)
|
|
state.p1 = state.p.subtract(BigInteger.ONE);
|
|
state.q1 = state.q.subtract(BigInteger.ONE);
|
|
state.phi = state.p1.multiply(state.q1);
|
|
|
|
// ensure e and phi are coprime
|
|
if(state.phi.gcd(state.e).compareTo(BigInteger.ONE) !== 0) {
|
|
// phi and e aren't coprime, so generate a new p and q
|
|
state.p = state.q = null;
|
|
generate();
|
|
return;
|
|
}
|
|
|
|
// create n, ensure n is has the right number of bits
|
|
state.n = state.p.multiply(state.q);
|
|
if(state.n.bitLength() !== state.bits) {
|
|
// failed, get new q
|
|
state.q = null;
|
|
getPrime(state.qBits, finish);
|
|
return;
|
|
}
|
|
|
|
// set keys
|
|
var d = state.e.modInverse(state.phi);
|
|
state.keys = {
|
|
privateKey: pki.rsa.setPrivateKey(
|
|
state.n, state.e, d, state.p, state.q,
|
|
d.mod(state.p1), d.mod(state.q1),
|
|
state.q.modInverse(state.p)),
|
|
publicKey: pki.rsa.setPublicKey(state.n, state.e)
|
|
};
|
|
|
|
callback(null, state.keys);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Converts a positive BigInteger into 2's-complement big-endian bytes.
|
|
*
|
|
* @param b the big integer to convert.
|
|
*
|
|
* @return the bytes.
|
|
*/
|
|
function _bnToBytes(b) {
|
|
// prepend 0x00 if first byte >= 0x80
|
|
var hex = b.toString(16);
|
|
if(hex[0] >= '8') {
|
|
hex = '00' + hex;
|
|
}
|
|
var bytes = forge.util.hexToBytes(hex);
|
|
|
|
// ensure integer is minimally-encoded
|
|
if(bytes.length > 1 &&
|
|
// leading 0x00 for positive integer
|
|
((bytes.charCodeAt(0) === 0 &&
|
|
(bytes.charCodeAt(1) & 0x80) === 0) ||
|
|
// leading 0xFF for negative integer
|
|
(bytes.charCodeAt(0) === 0xFF &&
|
|
(bytes.charCodeAt(1) & 0x80) === 0x80))) {
|
|
return bytes.substr(1);
|
|
}
|
|
return bytes;
|
|
}
|
|
|
|
/**
|
|
* Returns the required number of Miller-Rabin tests to generate a
|
|
* prime with an error probability of (1/2)^80.
|
|
*
|
|
* See Handbook of Applied Cryptography Chapter 4, Table 4.4.
|
|
*
|
|
* @param bits the bit size.
|
|
*
|
|
* @return the required number of iterations.
|
|
*/
|
|
function _getMillerRabinTests(bits) {
|
|
if(bits <= 100) return 27;
|
|
if(bits <= 150) return 18;
|
|
if(bits <= 200) return 15;
|
|
if(bits <= 250) return 12;
|
|
if(bits <= 300) return 9;
|
|
if(bits <= 350) return 8;
|
|
if(bits <= 400) return 7;
|
|
if(bits <= 500) return 6;
|
|
if(bits <= 600) return 5;
|
|
if(bits <= 800) return 4;
|
|
if(bits <= 1250) return 3;
|
|
return 2;
|
|
}
|
|
|
|
/**
|
|
* Performs feature detection on the SubtleCrypto interface.
|
|
*
|
|
* @param fn the feature (function) to detect.
|
|
*
|
|
* @return true if detected, false if not.
|
|
*/
|
|
function _detectSubtleCrypto(fn) {
|
|
return (typeof window !== 'undefined' &&
|
|
typeof window.crypto === 'object' &&
|
|
typeof window.crypto.subtle === 'object' &&
|
|
typeof window.crypto.subtle[fn] === 'function');
|
|
}
|
|
|
|
/**
|
|
* Performs feature detection on the deprecated Microsoft Internet Explorer
|
|
* outdated SubtleCrypto interface. This function should only be used after
|
|
* checking for the modern, standard SubtleCrypto interface.
|
|
*
|
|
* @param fn the feature (function) to detect.
|
|
*
|
|
* @return true if detected, false if not.
|
|
*/
|
|
function _detectSubtleMsCrypto(fn) {
|
|
return (typeof window !== 'undefined' &&
|
|
typeof window.msCrypto === 'object' &&
|
|
typeof window.msCrypto.subtle === 'object' &&
|
|
typeof window.msCrypto.subtle[fn] === 'function');
|
|
}
|
|
|
|
function _intToUint8Array(x) {
|
|
var bytes = forge.util.hexToBytes(x.toString(16));
|
|
var buffer = new Uint8Array(bytes.length);
|
|
for(var i = 0; i < bytes.length; ++i) {
|
|
buffer[i] = bytes.charCodeAt(i);
|
|
}
|
|
return buffer;
|
|
}
|
|
|
|
function _privateKeyFromJwk(jwk) {
|
|
if(jwk.kty !== 'RSA') {
|
|
throw new Error(
|
|
'Unsupported key algorithm "' + jwk.kty + '"; algorithm must be "RSA".');
|
|
}
|
|
return pki.setRsaPrivateKey(
|
|
_base64ToBigInt(jwk.n),
|
|
_base64ToBigInt(jwk.e),
|
|
_base64ToBigInt(jwk.d),
|
|
_base64ToBigInt(jwk.p),
|
|
_base64ToBigInt(jwk.q),
|
|
_base64ToBigInt(jwk.dp),
|
|
_base64ToBigInt(jwk.dq),
|
|
_base64ToBigInt(jwk.qi));
|
|
}
|
|
|
|
function _publicKeyFromJwk(jwk) {
|
|
if(jwk.kty !== 'RSA') {
|
|
throw new Error('Key algorithm must be "RSA".');
|
|
}
|
|
return pki.setRsaPublicKey(
|
|
_base64ToBigInt(jwk.n),
|
|
_base64ToBigInt(jwk.e));
|
|
}
|
|
|
|
function _base64ToBigInt(b64) {
|
|
return new BigInteger(forge.util.bytesToHex(forge.util.decode64(b64)), 16);
|
|
}
|