/**
* Break a public or private key down into its constituent components
*
* @access public
* @param string $key
* @param string $password optional
* @return array
*/
static function load($key, $password = '')
{
if (!is_string($key)) {
return false;
}
$components = array('isPublicKey' => strpos($key, 'PUBLIC') !== false);
/* Although PKCS#1 proposes a format that public and private keys can use, encrypting them is
"outside the scope" of PKCS#1. PKCS#1 then refers you to PKCS#12 and PKCS#15 if you're wanting to
protect private keys, however, that's not what OpenSSL* does. OpenSSL protects private keys by adding
two new "fields" to the key - DEK-Info and Proc-Type. These fields are discussed here:
http://tools.ietf.org/html/rfc1421#section-4.6.1.1
http://tools.ietf.org/html/rfc1421#section-4.6.1.3
DES-EDE3-CBC as an algorithm, however, is not discussed anywhere, near as I can tell.
DES-CBC and DES-EDE are discussed in RFC1423, however, DES-EDE3-CBC isn't, nor is its key derivation
function. As is, the definitive authority on this encoding scheme isn't the IETF but rather OpenSSL's
own implementation. ie. the implementation *is* the standard and any bugs that may exist in that
implementation are part of the standard, as well.
* OpenSSL is the de facto standard. It's utilized by OpenSSH and other projects */
if (preg_match('#DEK-Info: (.+),(.+)#', $key, $matches)) {
$iv = Hex::decode(trim($matches[2]));
// remove the Proc-Type / DEK-Info sections as they're no longer needed
$key = preg_replace('#^(?:Proc-Type|DEK-Info): .*#m', '', $key);
$ciphertext = self::_extractBER($key);
if ($ciphertext === false) {
$ciphertext = $key;
}
$crypto = self::getEncryptionObject($matches[1]);
$crypto->setKey(self::generateSymmetricKey($password, $iv, $crypto->getKeyLength() >> 3));
$crypto->setIV($iv);
$key = $crypto->decrypt($ciphertext);
if ($key === false) {
return false;
}
} else {
if (self::$format != self::MODE_DER) {
$decoded = self::_extractBER($key);
if ($decoded !== false) {
$key = $decoded;
} elseif (self::$format == self::MODE_PEM) {
return false;
}
}
}
if (ord(Strings::shift($key)) != self::ASN1_SEQUENCE) {
return false;
}
if (ASN1::decodeLength($key) != strlen($key)) {
return false;
}
$tag = ord(Strings::shift($key));
/* intended for keys for which OpenSSL's asn1parse returns the following:
0:d=0 hl=4 l= 631 cons: SEQUENCE
4:d=1 hl=2 l= 1 prim: INTEGER :00
7:d=1 hl=2 l= 13 cons: SEQUENCE
9:d=2 hl=2 l= 9 prim: OBJECT :rsaEncryption
20:d=2 hl=2 l= 0 prim: NULL
22:d=1 hl=4 l= 609 prim: OCTET STRING
ie. PKCS8 keys */
if ($tag == self::ASN1_INTEGER && substr($key, 0, 3) == "0") {
Strings::shift($key, 3);
$tag = self::ASN1_SEQUENCE;
}
if ($tag == self::ASN1_SEQUENCE) {
$temp = Strings::shift($key, ASN1::decodeLength($key));
if (ord(Strings::shift($temp)) != self::ASN1_OBJECT) {
return false;
}
$length = ASN1::decodeLength($temp);
switch (Strings::shift($temp, $length)) {
case "*†H†÷\r":
// rsaEncryption
break;
case "*†H†÷\r":
// pbeWithMD5AndDES-CBC
/*
PBEParameter ::= SEQUENCE {
salt OCTET STRING (SIZE(8)),
iterationCount INTEGER }
*/
if (ord(Strings::shift($temp)) != self::ASN1_SEQUENCE) {
return false;
}
if (ASN1::decodeLength($temp) != strlen($temp)) {
return false;
}
Strings::shift($temp);
// assume it's an octet string
$salt = Strings::shift($temp, ASN1::decodeLength($temp));
if (ord(Strings::shift($temp)) != self::ASN1_INTEGER) {
return false;
}
ASN1::decodeLength($temp);
list(, $iterationCount) = unpack('N', str_pad($temp, 4, chr(0), STR_PAD_LEFT));
Strings::shift($key);
// assume it's an octet string
$length = ASN1::decodeLength($key);
if (strlen($key) != $length) {
return false;
}
$crypto = new DES(DES::MODE_CBC);
$crypto->setPassword($password, 'pbkdf1', 'md5', $salt, $iterationCount);
$key = $crypto->decrypt($key);
if ($key === false) {
return false;
}
return self::load($key);
default:
return false;
}
/* intended for keys for which OpenSSL's asn1parse returns the following:
0:d=0 hl=4 l= 290 cons: SEQUENCE
4:d=1 hl=2 l= 13 cons: SEQUENCE
6:d=2 hl=2 l= 9 prim: OBJECT :rsaEncryption
17:d=2 hl=2 l= 0 prim: NULL
19:d=1 hl=4 l= 271 prim: BIT STRING */
$tag = ord(Strings::shift($key));
// skip over the BIT STRING / OCTET STRING tag
ASN1::decodeLength($key);
// skip over the BIT STRING / OCTET STRING length
// "The initial octet shall encode, as an unsigned binary integer wtih bit 1 as the least significant bit, the number of
// unused bits in the final subsequent octet. The number shall be in the range zero to seven."
// -- http://www.itu.int/ITU-T/studygroups/com17/languages/X.690-0207.pdf (section 8.6.2.2)
if ($tag == self::ASN1_BITSTRING) {
Strings::shift($key);
}
if (ord(Strings::shift($key)) != self::ASN1_SEQUENCE) {
return false;
}
if (ASN1::decodeLength($key) != strlen($key)) {
return false;
}
$tag = ord(Strings::shift($key));
}
if ($tag != self::ASN1_INTEGER) {
return false;
}
$length = ASN1::decodeLength($key);
$temp = Strings::shift($key, $length);
if (strlen($temp) != 1 || ord($temp) > 2) {
$components['modulus'] = new BigInteger($temp, 256);
Strings::shift($key);
// skip over self::ASN1_INTEGER
$length = ASN1::decodeLength($key);
$components[$components['isPublicKey'] ? 'publicExponent' : 'privateExponent'] = new BigInteger(Strings::shift($key, $length), 256);
return $components;
}
if (ord(Strings::shift($key)) != self::ASN1_INTEGER) {
return false;
}
$length = ASN1::decodeLength($key);
$components['modulus'] = new BigInteger(Strings::shift($key, $length), 256);
Strings::shift($key);
$length = ASN1::decodeLength($key);
$components['publicExponent'] = new BigInteger(Strings::shift($key, $length), 256);
Strings::shift($key);
$length = ASN1::decodeLength($key);
$components['privateExponent'] = new BigInteger(Strings::shift($key, $length), 256);
Strings::shift($key);
$length = ASN1::decodeLength($key);
$components['primes'] = array(1 => new BigInteger(Strings::shift($key, $length), 256));
Strings::shift($key);
$length = ASN1::decodeLength($key);
$components['primes'][] = new BigInteger(Strings::shift($key, $length), 256);
Strings::shift($key);
$length = ASN1::decodeLength($key);
$components['exponents'] = array(1 => new BigInteger(Strings::shift($key, $length), 256));
Strings::shift($key);
$length = ASN1::decodeLength($key);
$components['exponents'][] = new BigInteger(Strings::shift($key, $length), 256);
Strings::shift($key);
$length = ASN1::decodeLength($key);
$components['coefficients'] = array(2 => new BigInteger(Strings::shift($key, $length), 256));
if (!empty($key)) {
if (ord(Strings::shift($key)) != self::ASN1_SEQUENCE) {
return false;
}
ASN1::decodeLength($key);
while (!empty($key)) {
if (ord(Strings::shift($key)) != self::ASN1_SEQUENCE) {
return false;
}
ASN1::decodeLength($key);
$key = substr($key, 1);
$length = ASN1::decodeLength($key);
$components['primes'][] = new BigInteger(Strings::shift($key, $length), 256);
Strings::shift($key);
$length = ASN1::decodeLength($key);
$components['exponents'][] = new BigInteger(Strings::shift($key, $length), 256);
Strings::shift($key);
$length = ASN1::decodeLength($key);
$components['coefficients'][] = new BigInteger(Strings::shift($key, $length), 256);
}
}
return $components;
}
/**
* Convert a private key to the appropriate format.
*
* @access private
* @see setPrivateKeyFormat()
*
* @param String $RSAPrivateKey
*
* @return String
*/
function _convertPrivateKey($n, $e, $d, $primes, $exponents, $coefficients)
{
$signed = $this->privateKeyFormat != self::PRIVATE_FORMAT_XML;
$num_primes = count($primes);
$raw = array('version' => $num_primes == 2 ? chr(0) : chr(1), 'modulus' => $n->toBytes($signed), 'publicExponent' => $e->toBytes($signed), 'privateExponent' => $d->toBytes($signed), 'prime1' => $primes[1]->toBytes($signed), 'prime2' => $primes[2]->toBytes($signed), 'exponent1' => $exponents[1]->toBytes($signed), 'exponent2' => $exponents[2]->toBytes($signed), 'coefficient' => $coefficients[2]->toBytes($signed));
// if the format in question does not support multi-prime rsa and multi-prime rsa was used,
// call _convertPublicKey() instead.
switch ($this->privateKeyFormat) {
case self::PRIVATE_FORMAT_XML:
if ($num_primes != 2) {
return false;
}
return "<RSAKeyValue>\r\n" . ' <Modulus>' . base64_encode($raw['modulus']) . "</Modulus>\r\n" . ' <Exponent>' . base64_encode($raw['publicExponent']) . "</Exponent>\r\n" . ' <P>' . base64_encode($raw['prime1']) . "</P>\r\n" . ' <Q>' . base64_encode($raw['prime2']) . "</Q>\r\n" . ' <DP>' . base64_encode($raw['exponent1']) . "</DP>\r\n" . ' <DQ>' . base64_encode($raw['exponent2']) . "</DQ>\r\n" . ' <InverseQ>' . base64_encode($raw['coefficient']) . "</InverseQ>\r\n" . ' <D>' . base64_encode($raw['privateExponent']) . "</D>\r\n" . '</RSAKeyValue>';
break;
case self::PRIVATE_FORMAT_PUTTY:
if ($num_primes != 2) {
return false;
}
$key = "PuTTY-User-Key-File-2: ssh-rsa\r\nEncryption: ";
$encryption = !empty($this->password) || is_string($this->password) ? 'aes256-cbc' : 'none';
$key .= $encryption;
$key .= "\r\nComment: " . $this->comment . "\r\n";
$public = pack('Na*Na*Na*', strlen('ssh-rsa'), 'ssh-rsa', strlen($raw['publicExponent']), $raw['publicExponent'], strlen($raw['modulus']), $raw['modulus']);
$source = pack('Na*Na*Na*Na*', strlen('ssh-rsa'), 'ssh-rsa', strlen($encryption), $encryption, strlen($this->comment), $this->comment, strlen($public), $public);
$public = base64_encode($public);
$key .= "Public-Lines: " . (strlen($public) + 63 >> 6) . "\r\n";
$key .= chunk_split($public, 64);
$private = pack('Na*Na*Na*Na*', strlen($raw['privateExponent']), $raw['privateExponent'], strlen($raw['prime1']), $raw['prime1'], strlen($raw['prime2']), $raw['prime2'], strlen($raw['coefficient']), $raw['coefficient']);
if (empty($this->password) && !is_string($this->password)) {
$source .= pack('Na*', strlen($private), $private);
$hashkey = 'putty-private-key-file-mac-key';
} else {
$private .= Random::string(16 - (strlen($private) & 15));
$source .= pack('Na*', strlen($private), $private);
$sequence = 0;
$symkey = '';
while (strlen($symkey) < 32) {
$temp = pack('Na*', $sequence++, $this->password);
$symkey .= pack('H*', sha1($temp));
}
$symkey = substr($symkey, 0, 32);
$crypto = new AES();
$crypto->setKey($symkey);
$crypto->disablePadding();
$private = $crypto->encrypt($private);
$hashkey = 'putty-private-key-file-mac-key' . $this->password;
}
$private = base64_encode($private);
$key .= 'Private-Lines: ' . (strlen($private) + 63 >> 6) . "\r\n";
$key .= chunk_split($private, 64);
$hash = new Hash('sha1');
$hash->setKey(pack('H*', sha1($hashkey)));
$key .= 'Private-MAC: ' . bin2hex($hash->hash($source)) . "\r\n";
return $key;
default:
// eg. self::PRIVATE_FORMAT_PKCS1
$components = array();
foreach ($raw as $name => $value) {
$components[$name] = pack('Ca*a*', self::ASN1_INTEGER, $this->_encodeLength(strlen($value)), $value);
}
$RSAPrivateKey = implode('', $components);
if ($num_primes > 2) {
$OtherPrimeInfos = '';
for ($i = 3; $i <= $num_primes; $i++) {
// OtherPrimeInfos ::= SEQUENCE SIZE(1..MAX) OF OtherPrimeInfo
//
// OtherPrimeInfo ::= SEQUENCE {
// prime INTEGER, -- ri
// exponent INTEGER, -- di
// coefficient INTEGER -- ti
// }
$OtherPrimeInfo = pack('Ca*a*', self::ASN1_INTEGER, $this->_encodeLength(strlen($primes[$i]->toBytes(true))), $primes[$i]->toBytes(true));
$OtherPrimeInfo .= pack('Ca*a*', self::ASN1_INTEGER, $this->_encodeLength(strlen($exponents[$i]->toBytes(true))), $exponents[$i]->toBytes(true));
$OtherPrimeInfo .= pack('Ca*a*', self::ASN1_INTEGER, $this->_encodeLength(strlen($coefficients[$i]->toBytes(true))), $coefficients[$i]->toBytes(true));
$OtherPrimeInfos .= pack('Ca*a*', self::ASN1_SEQUENCE, $this->_encodeLength(strlen($OtherPrimeInfo)), $OtherPrimeInfo);
}
$RSAPrivateKey .= pack('Ca*a*', self::ASN1_SEQUENCE, $this->_encodeLength(strlen($OtherPrimeInfos)), $OtherPrimeInfos);
}
$RSAPrivateKey = pack('Ca*a*', self::ASN1_SEQUENCE, $this->_encodeLength(strlen($RSAPrivateKey)), $RSAPrivateKey);
if ($this->privateKeyFormat == self::PRIVATE_FORMAT_PKCS8) {
$rsaOID = pack('H*', '300d06092a864886f70d0101010500');
// hex version of MA0GCSqGSIb3DQEBAQUA
$RSAPrivateKey = pack('Ca*a*Ca*a*', self::ASN1_INTEGER, "", $rsaOID, 4, $this->_encodeLength(strlen($RSAPrivateKey)), $RSAPrivateKey);
$RSAPrivateKey = pack('Ca*a*', self::ASN1_SEQUENCE, $this->_encodeLength(strlen($RSAPrivateKey)), $RSAPrivateKey);
if (!empty($this->password) || is_string($this->password)) {
$salt = Random::string(8);
$iterationCount = 2048;
$crypto = new DES();
$crypto->setPassword($this->password, 'pbkdf1', 'md5', $salt, $iterationCount);
$RSAPrivateKey = $crypto->encrypt($RSAPrivateKey);
$parameters = pack('Ca*a*Ca*N', self::ASN1_OCTETSTRING, $this->_encodeLength(strlen($salt)), $salt, self::ASN1_INTEGER, $this->_encodeLength(4), $iterationCount);
$pbeWithMD5AndDES_CBC = "*†H†÷\r";
$encryptionAlgorithm = pack('Ca*a*Ca*a*', self::ASN1_OBJECT, $this->_encodeLength(strlen($pbeWithMD5AndDES_CBC)), $pbeWithMD5AndDES_CBC, self::ASN1_SEQUENCE, $this->_encodeLength(strlen($parameters)), $parameters);
$RSAPrivateKey = pack('Ca*a*Ca*a*', self::ASN1_SEQUENCE, $this->_encodeLength(strlen($encryptionAlgorithm)), $encryptionAlgorithm, self::ASN1_OCTETSTRING, $this->_encodeLength(strlen($RSAPrivateKey)), $RSAPrivateKey);
$RSAPrivateKey = pack('Ca*a*', self::ASN1_SEQUENCE, $this->_encodeLength(strlen($RSAPrivateKey)), $RSAPrivateKey);
$RSAPrivateKey = "-----BEGIN ENCRYPTED PRIVATE KEY-----\r\n" . chunk_split(base64_encode($RSAPrivateKey), 64) . '-----END ENCRYPTED PRIVATE KEY-----';
} else {
$RSAPrivateKey = "-----BEGIN PRIVATE KEY-----\r\n" . chunk_split(base64_encode($RSAPrivateKey), 64) . '-----END PRIVATE KEY-----';
}
return $RSAPrivateKey;
}
if (!empty($this->password) || is_string($this->password)) {
$iv = Random::string(8);
$symkey = pack('H*', md5($this->password . $iv));
// symkey is short for symmetric key
$symkey .= substr(pack('H*', md5($symkey . $this->password . $iv)), 0, 8);
$des = new TripleDES();
$des->setKey($symkey);
$des->setIV($iv);
$iv = strtoupper(bin2hex($iv));
$RSAPrivateKey = "-----BEGIN RSA PRIVATE KEY-----\r\n" . "Proc-Type: 4,ENCRYPTED\r\n" . "DEK-Info: DES-EDE3-CBC,{$iv}\r\n" . "\r\n" . chunk_split(base64_encode($des->encrypt($RSAPrivateKey)), 64) . '-----END RSA PRIVATE KEY-----';
} else {
$RSAPrivateKey = "-----BEGIN RSA PRIVATE KEY-----\r\n" . chunk_split(base64_encode($RSAPrivateKey), 64) . '-----END RSA PRIVATE KEY-----';
}
return $RSAPrivateKey;
}
}
/**
* Break a public or private key down into its constituant components
*
* @access private
* @see self::_convertPublicKey()
* @see self::_convertPrivateKey()
* @param string $key
* @param int $type
* @return array
*/
function _parseKey($key, $type)
{
if ($type != self::PUBLIC_FORMAT_RAW && !is_string($key)) {
return false;
}
switch ($type) {
case self::PUBLIC_FORMAT_RAW:
if (!is_array($key)) {
return false;
}
$components = array();
switch (true) {
case isset($key['e']):
$components['publicExponent'] = $key['e']->copy();
break;
case isset($key['exponent']):
$components['publicExponent'] = $key['exponent']->copy();
break;
case isset($key['publicExponent']):
$components['publicExponent'] = $key['publicExponent']->copy();
break;
case isset($key[0]):
$components['publicExponent'] = $key[0]->copy();
}
switch (true) {
case isset($key['n']):
$components['modulus'] = $key['n']->copy();
break;
case isset($key['modulo']):
$components['modulus'] = $key['modulo']->copy();
break;
case isset($key['modulus']):
$components['modulus'] = $key['modulus']->copy();
break;
case isset($key[1]):
$components['modulus'] = $key[1]->copy();
}
return isset($components['modulus']) && isset($components['publicExponent']) ? $components : false;
case self::PRIVATE_FORMAT_PKCS1:
case self::PRIVATE_FORMAT_PKCS8:
case self::PUBLIC_FORMAT_PKCS1:
/* Although PKCS#1 proposes a format that public and private keys can use, encrypting them is
"outside the scope" of PKCS#1. PKCS#1 then refers you to PKCS#12 and PKCS#15 if you're wanting to
protect private keys, however, that's not what OpenSSL* does. OpenSSL protects private keys by adding
two new "fields" to the key - DEK-Info and Proc-Type. These fields are discussed here:
http://tools.ietf.org/html/rfc1421#section-4.6.1.1
http://tools.ietf.org/html/rfc1421#section-4.6.1.3
DES-EDE3-CBC as an algorithm, however, is not discussed anywhere, near as I can tell.
DES-CBC and DES-EDE are discussed in RFC1423, however, DES-EDE3-CBC isn't, nor is its key derivation
function. As is, the definitive authority on this encoding scheme isn't the IETF but rather OpenSSL's
own implementation. ie. the implementation *is* the standard and any bugs that may exist in that
implementation are part of the standard, as well.
* OpenSSL is the de facto standard. It's utilized by OpenSSH and other projects */
if (preg_match('#DEK-Info: (.+),(.+)#', $key, $matches)) {
$iv = pack('H*', trim($matches[2]));
$symkey = pack('H*', md5($this->password . substr($iv, 0, 8))); // symkey is short for symmetric key
$symkey.= pack('H*', md5($symkey . $this->password . substr($iv, 0, 8)));
// remove the Proc-Type / DEK-Info sections as they're no longer needed
$key = preg_replace('#^(?:Proc-Type|DEK-Info): .*#m', '', $key);
$ciphertext = $this->_extractBER($key);
if ($ciphertext === false) {
$ciphertext = $key;
}
switch ($matches[1]) {
case 'AES-256-CBC':
$crypto = new AES();
break;
case 'AES-128-CBC':
$symkey = substr($symkey, 0, 16);
$crypto = new AES();
break;
case 'DES-EDE3-CFB':
$crypto = new TripleDES(Base::MODE_CFB);
break;
case 'DES-EDE3-CBC':
$symkey = substr($symkey, 0, 24);
$crypto = new TripleDES();
break;
case 'DES-CBC':
$crypto = new DES();
break;
default:
return false;
}
$crypto->setKey($symkey);
$crypto->setIV($iv);
$decoded = $crypto->decrypt($ciphertext);
} else {
$decoded = $this->_extractBER($key);
}
if ($decoded !== false) {
$key = $decoded;
}
$components = array();
if (ord($this->_string_shift($key)) != self::ASN1_SEQUENCE) {
return false;
}
if ($this->_decodeLength($key) != strlen($key)) {
return false;
}
$tag = ord($this->_string_shift($key));
/* intended for keys for which OpenSSL's asn1parse returns the following:
0:d=0 hl=4 l= 631 cons: SEQUENCE
4:d=1 hl=2 l= 1 prim: INTEGER :00
7:d=1 hl=2 l= 13 cons: SEQUENCE
9:d=2 hl=2 l= 9 prim: OBJECT :rsaEncryption
20:d=2 hl=2 l= 0 prim: NULL
22:d=1 hl=4 l= 609 prim: OCTET STRING
ie. PKCS8 keys*/
if ($tag == self::ASN1_INTEGER && substr($key, 0, 3) == "\x01\x00\x30") {
$this->_string_shift($key, 3);
$tag = self::ASN1_SEQUENCE;
}
if ($tag == self::ASN1_SEQUENCE) {
$temp = $this->_string_shift($key, $this->_decodeLength($key));
if (ord($this->_string_shift($temp)) != self::ASN1_OBJECT) {
return false;
}
$length = $this->_decodeLength($temp);
switch ($this->_string_shift($temp, $length)) {
case "\x2a\x86\x48\x86\xf7\x0d\x01\x01\x01": // rsaEncryption
break;
case "\x2a\x86\x48\x86\xf7\x0d\x01\x05\x03": // pbeWithMD5AndDES-CBC
/*
PBEParameter ::= SEQUENCE {
salt OCTET STRING (SIZE(8)),
iterationCount INTEGER }
*/
if (ord($this->_string_shift($temp)) != self::ASN1_SEQUENCE) {
return false;
}
if ($this->_decodeLength($temp) != strlen($temp)) {
return false;
}
$this->_string_shift($temp); // assume it's an octet string
$salt = $this->_string_shift($temp, $this->_decodeLength($temp));
if (ord($this->_string_shift($temp)) != self::ASN1_INTEGER) {
return false;
}
$this->_decodeLength($temp);
list(, $iterationCount) = unpack('N', str_pad($temp, 4, chr(0), STR_PAD_LEFT));
$this->_string_shift($key); // assume it's an octet string
$length = $this->_decodeLength($key);
if (strlen($key) != $length) {
return false;
}
$crypto = new DES();
$crypto->setPassword($this->password, 'pbkdf1', 'md5', $salt, $iterationCount);
$key = $crypto->decrypt($key);
if ($key === false) {
return false;
}
return $this->_parseKey($key, self::PRIVATE_FORMAT_PKCS1);
default:
return false;
}
/* intended for keys for which OpenSSL's asn1parse returns the following:
0:d=0 hl=4 l= 290 cons: SEQUENCE
4:d=1 hl=2 l= 13 cons: SEQUENCE
6:d=2 hl=2 l= 9 prim: OBJECT :rsaEncryption
17:d=2 hl=2 l= 0 prim: NULL
19:d=1 hl=4 l= 271 prim: BIT STRING */
$tag = ord($this->_string_shift($key)); // skip over the BIT STRING / OCTET STRING tag
$this->_decodeLength($key); // skip over the BIT STRING / OCTET STRING length
// "The initial octet shall encode, as an unsigned binary integer wtih bit 1 as the least significant bit, the number of
// unused bits in the final subsequent octet. The number shall be in the range zero to seven."
// -- http://www.itu.int/ITU-T/studygroups/com17/languages/X.690-0207.pdf (section 8.6.2.2)
if ($tag == self::ASN1_BITSTRING) {
$this->_string_shift($key);
}
if (ord($this->_string_shift($key)) != self::ASN1_SEQUENCE) {
return false;
}
if ($this->_decodeLength($key) != strlen($key)) {
return false;
}
$tag = ord($this->_string_shift($key));
}
if ($tag != self::ASN1_INTEGER) {
return false;
}
$length = $this->_decodeLength($key);
$temp = $this->_string_shift($key, $length);
if (strlen($temp) != 1 || ord($temp) > 2) {
$components['modulus'] = new BigInteger($temp, 256);
$this->_string_shift($key); // skip over self::ASN1_INTEGER
$length = $this->_decodeLength($key);
$components[$type == self::PUBLIC_FORMAT_PKCS1 ? 'publicExponent' : 'privateExponent'] = new BigInteger($this->_string_shift($key, $length), 256);
return $components;
}
if (ord($this->_string_shift($key)) != self::ASN1_INTEGER) {
return false;
}
$length = $this->_decodeLength($key);
$components['modulus'] = new BigInteger($this->_string_shift($key, $length), 256);
$this->_string_shift($key);
$length = $this->_decodeLength($key);
$components['publicExponent'] = new BigInteger($this->_string_shift($key, $length), 256);
$this->_string_shift($key);
$length = $this->_decodeLength($key);
$components['privateExponent'] = new BigInteger($this->_string_shift($key, $length), 256);
$this->_string_shift($key);
$length = $this->_decodeLength($key);
$components['primes'] = array(1 => new BigInteger($this->_string_shift($key, $length), 256));
$this->_string_shift($key);
$length = $this->_decodeLength($key);
$components['primes'][] = new BigInteger($this->_string_shift($key, $length), 256);
$this->_string_shift($key);
$length = $this->_decodeLength($key);
$components['exponents'] = array(1 => new BigInteger($this->_string_shift($key, $length), 256));
$this->_string_shift($key);
$length = $this->_decodeLength($key);
$components['exponents'][] = new BigInteger($this->_string_shift($key, $length), 256);
$this->_string_shift($key);
$length = $this->_decodeLength($key);
$components['coefficients'] = array(2 => new BigInteger($this->_string_shift($key, $length), 256));
if (!empty($key)) {
if (ord($this->_string_shift($key)) != self::ASN1_SEQUENCE) {
return false;
}
$this->_decodeLength($key);
while (!empty($key)) {
if (ord($this->_string_shift($key)) != self::ASN1_SEQUENCE) {
return false;
}
$this->_decodeLength($key);
$key = substr($key, 1);
$length = $this->_decodeLength($key);
$components['primes'][] = new BigInteger($this->_string_shift($key, $length), 256);
$this->_string_shift($key);
$length = $this->_decodeLength($key);
$components['exponents'][] = new BigInteger($this->_string_shift($key, $length), 256);
$this->_string_shift($key);
$length = $this->_decodeLength($key);
$components['coefficients'][] = new BigInteger($this->_string_shift($key, $length), 256);
}
}
return $components;
case self::PUBLIC_FORMAT_OPENSSH:
$parts = explode(' ', $key, 3);
$key = isset($parts[1]) ? base64_decode($parts[1]) : false;
if ($key === false) {
return false;
}
$comment = isset($parts[2]) ? $parts[2] : false;
$cleanup = substr($key, 0, 11) == "\0\0\0\7ssh-rsa";
if (strlen($key) <= 4) {
return false;
}
extract(unpack('Nlength', $this->_string_shift($key, 4)));
$publicExponent = new BigInteger($this->_string_shift($key, $length), -256);
if (strlen($key) <= 4) {
return false;
}
extract(unpack('Nlength', $this->_string_shift($key, 4)));
$modulus = new BigInteger($this->_string_shift($key, $length), -256);
if ($cleanup && strlen($key)) {
if (strlen($key) <= 4) {
return false;
}
extract(unpack('Nlength', $this->_string_shift($key, 4)));
$realModulus = new BigInteger($this->_string_shift($key, $length), -256);
return strlen($key) ? false : array(
'modulus' => $realModulus,
'publicExponent' => $modulus,
'comment' => $comment
);
} else {
return strlen($key) ? false : array(
'modulus' => $modulus,
'publicExponent' => $publicExponent,
'comment' => $comment
);
}
// http://www.w3.org/TR/xmldsig-core/#sec-RSAKeyValue
// http://en.wikipedia.org/wiki/XML_Signature
case self::PRIVATE_FORMAT_XML:
case self::PUBLIC_FORMAT_XML:
$this->components = array();
$xml = xml_parser_create('UTF-8');
xml_set_object($xml, $this);
xml_set_element_handler($xml, '_start_element_handler', '_stop_element_handler');
xml_set_character_data_handler($xml, '_data_handler');
// add <xml></xml> to account for "dangling" tags like <BitStrength>...</BitStrength> that are sometimes added
if (!xml_parse($xml, '<xml>' . $key . '</xml>')) {
return false;
}
return isset($this->components['modulus']) && isset($this->components['publicExponent']) ? $this->components : false;
// from PuTTY's SSHPUBK.C
case self::PRIVATE_FORMAT_PUTTY:
$components = array();
$key = preg_split('#\r\n|\r|\n#', $key);
$type = trim(preg_replace('#PuTTY-User-Key-File-2: (.+)#', '$1', $key[0]));
if ($type != 'ssh-rsa') {
return false;
}
$encryption = trim(preg_replace('#Encryption: (.+)#', '$1', $key[1]));
$comment = trim(preg_replace('#Comment: (.+)#', '$1', $key[2]));
$publicLength = trim(preg_replace('#Public-Lines: (\d+)#', '$1', $key[3]));
$public = base64_decode(implode('', array_map('trim', array_slice($key, 4, $publicLength))));
$public = substr($public, 11);
extract(unpack('Nlength', $this->_string_shift($public, 4)));
$components['publicExponent'] = new BigInteger($this->_string_shift($public, $length), -256);
extract(unpack('Nlength', $this->_string_shift($public, 4)));
$components['modulus'] = new BigInteger($this->_string_shift($public, $length), -256);
$privateLength = trim(preg_replace('#Private-Lines: (\d+)#', '$1', $key[$publicLength + 4]));
$private = base64_decode(implode('', array_map('trim', array_slice($key, $publicLength + 5, $privateLength))));
switch ($encryption) {
case 'aes256-cbc':
$symkey = '';
$sequence = 0;
while (strlen($symkey) < 32) {
$temp = pack('Na*', $sequence++, $this->password);
$symkey.= pack('H*', sha1($temp));
}
$symkey = substr($symkey, 0, 32);
$crypto = new AES();
}
if ($encryption != 'none') {
$crypto->setKey($symkey);
$crypto->disablePadding();
$private = $crypto->decrypt($private);
if ($private === false) {
return false;
}
}
extract(unpack('Nlength', $this->_string_shift($private, 4)));
if (strlen($private) < $length) {
return false;
}
$components['privateExponent'] = new BigInteger($this->_string_shift($private, $length), -256);
extract(unpack('Nlength', $this->_string_shift($private, 4)));
if (strlen($private) < $length) {
return false;
}
$components['primes'] = array(1 => new BigInteger($this->_string_shift($private, $length), -256));
extract(unpack('Nlength', $this->_string_shift($private, 4)));
if (strlen($private) < $length) {
return false;
}
$components['primes'][] = new BigInteger($this->_string_shift($private, $length), -256);
$temp = $components['primes'][1]->subtract($this->one);
$components['exponents'] = array(1 => $components['publicExponent']->modInverse($temp));
$temp = $components['primes'][2]->subtract($this->one);
$components['exponents'][] = $components['publicExponent']->modInverse($temp);
extract(unpack('Nlength', $this->_string_shift($private, 4)));
if (strlen($private) < $length) {
return false;
}
$components['coefficients'] = array(2 => new BigInteger($this->_string_shift($private, $length), -256));
return $components;
}
}
/**
* Convert a private key to the appropriate format.
*
* @access public
* @param \phpseclib\Math\BigInteger $n
* @param \phpseclib\Math\BigInteger $e
* @param \phpseclib\Math\BigInteger $d
* @param array $primes
* @param array $exponents
* @param array $coefficients
* @param string $password optional
* @return string
*/
static function savePrivateKey(BigInteger $n, BigInteger $e, BigInteger $d, $primes, $exponents, $coefficients, $password = '')
{
$num_primes = count($primes);
$raw = array('version' => $num_primes == 2 ? chr(0) : chr(1), 'modulus' => $n->toBytes(true), 'publicExponent' => $e->toBytes(true), 'privateExponent' => $d->toBytes(true), 'prime1' => $primes[1]->toBytes(true), 'prime2' => $primes[2]->toBytes(true), 'exponent1' => $exponents[1]->toBytes(true), 'exponent2' => $exponents[2]->toBytes(true), 'coefficient' => $coefficients[2]->toBytes(true));
$components = array();
foreach ($raw as $name => $value) {
$components[$name] = pack('Ca*a*', self::ASN1_INTEGER, ASN1::encodeLength(strlen($value)), $value);
}
$RSAPrivateKey = implode('', $components);
if ($num_primes > 2) {
$OtherPrimeInfos = '';
for ($i = 3; $i <= $num_primes; $i++) {
// OtherPrimeInfos ::= SEQUENCE SIZE(1..MAX) OF OtherPrimeInfo
//
// OtherPrimeInfo ::= SEQUENCE {
// prime INTEGER, -- ri
// exponent INTEGER, -- di
// coefficient INTEGER -- ti
// }
$OtherPrimeInfo = pack('Ca*a*', self::ASN1_INTEGER, ASN1::encodeLength(strlen($primes[$i]->toBytes(true))), $primes[$i]->toBytes(true));
$OtherPrimeInfo .= pack('Ca*a*', self::ASN1_INTEGER, ASN1::encodeLength(strlen($exponents[$i]->toBytes(true))), $exponents[$i]->toBytes(true));
$OtherPrimeInfo .= pack('Ca*a*', self::ASN1_INTEGER, ASN1::encodeLength(strlen($coefficients[$i]->toBytes(true))), $coefficients[$i]->toBytes(true));
$OtherPrimeInfos .= pack('Ca*a*', self::ASN1_SEQUENCE, ASN1::encodeLength(strlen($OtherPrimeInfo)), $OtherPrimeInfo);
}
$RSAPrivateKey .= pack('Ca*a*', self::ASN1_SEQUENCE, ASN1::encodeLength(strlen($OtherPrimeInfos)), $OtherPrimeInfos);
}
$RSAPrivateKey = pack('Ca*a*', self::ASN1_SEQUENCE, ASN1::encodeLength(strlen($RSAPrivateKey)), $RSAPrivateKey);
$rsaOID = "0\r\t*†H†÷\r";
// hex version of MA0GCSqGSIb3DQEBAQUA
$RSAPrivateKey = pack('Ca*a*Ca*a*', self::ASN1_INTEGER, "", $rsaOID, 4, ASN1::encodeLength(strlen($RSAPrivateKey)), $RSAPrivateKey);
$RSAPrivateKey = pack('Ca*a*', self::ASN1_SEQUENCE, ASN1::encodeLength(strlen($RSAPrivateKey)), $RSAPrivateKey);
if (!empty($password) || is_string($password)) {
$salt = Random::string(8);
$iterationCount = 2048;
$crypto = new DES(DES::MODE_CBC);
$crypto->setPassword($password, 'pbkdf1', 'md5', $salt, $iterationCount);
$RSAPrivateKey = $crypto->encrypt($RSAPrivateKey);
$parameters = pack('Ca*a*Ca*N', self::ASN1_OCTETSTRING, ASN1::encodeLength(strlen($salt)), $salt, self::ASN1_INTEGER, ASN1::encodeLength(4), $iterationCount);
$pbeWithMD5AndDES_CBC = "*†H†÷\r";
$encryptionAlgorithm = pack('Ca*a*Ca*a*', self::ASN1_OBJECT, ASN1::encodeLength(strlen($pbeWithMD5AndDES_CBC)), $pbeWithMD5AndDES_CBC, self::ASN1_SEQUENCE, ASN1::encodeLength(strlen($parameters)), $parameters);
$RSAPrivateKey = pack('Ca*a*Ca*a*', self::ASN1_SEQUENCE, ASN1::encodeLength(strlen($encryptionAlgorithm)), $encryptionAlgorithm, self::ASN1_OCTETSTRING, ASN1::encodeLength(strlen($RSAPrivateKey)), $RSAPrivateKey);
$RSAPrivateKey = pack('Ca*a*', self::ASN1_SEQUENCE, ASN1::encodeLength(strlen($RSAPrivateKey)), $RSAPrivateKey);
$RSAPrivateKey = "-----BEGIN ENCRYPTED PRIVATE KEY-----\r\n" . chunk_split(Base64::encode($RSAPrivateKey), 64) . '-----END ENCRYPTED PRIVATE KEY-----';
} else {
$RSAPrivateKey = "-----BEGIN PRIVATE KEY-----\r\n" . chunk_split(Base64::encode($RSAPrivateKey), 64) . '-----END PRIVATE KEY-----';
}
return $RSAPrivateKey;
}
