openpgp-php/lib/openpgp.php
2010-03-30 12:54:51 -05:00

605 lines
17 KiB
PHP

<?php
// This is free and unencumbered software released into the public domain.
/**
* OpenPGP.php is a pure-PHP implementation of the OpenPGP Message Format
* (RFC 4880).
*
* @package OpenPGP
* @version 0.0.1
* @author Arto Bendiken <arto.bendiken@gmail.com>
* @link http://github.com/bendiken/openpgp-php
*/
//////////////////////////////////////////////////////////////////////////////
// OpenPGP utilities
/**
* @see http://tools.ietf.org/html/rfc4880
*/
class OpenPGP {
/**
* @see http://tools.ietf.org/html/rfc4880#section-6
* @see http://tools.ietf.org/html/rfc4880#section-6.2
* @see http://tools.ietf.org/html/rfc2045
*/
static function enarmor($data, $marker = 'MESSAGE', array $headers = array()) {
$text = self::header($marker) . "\n";
foreach ($headers as $key => $value) {
$text .= $key . ': ' . (string)$value . "\n";
}
$text .= "\n" . base64_encode($data);
$text .= '=' . substr(pack('N', self::crc24($data)), 1) . "\n";
$text .= self::footer($marker) . "\n";
return $text;
}
/**
* @see http://tools.ietf.org/html/rfc4880#section-6
* @see http://tools.ietf.org/html/rfc2045
*/
static function unarmor($text, $header = 'PGP PUBLIC KEY BLOCK') {
$header = self::header($header);
$text = str_replace(array("\r\n", "\r"), array("\n", ''), $text);
if (($pos1 = strpos($text, $header)) !== FALSE &&
($pos1 = strpos($text, "\n\n", $pos1 += strlen($header))) !== FALSE &&
($pos2 = strpos($text, "\n=", $pos1 += 2)) !== FALSE) {
return base64_decode($text = substr($text, $pos1, $pos2 - $pos1));
}
}
/**
* @see http://tools.ietf.org/html/rfc4880#section-6.2
*/
static function header($marker) {
return '-----BEGIN ' . strtoupper((string)$marker) . '-----';
}
/**
* @see http://tools.ietf.org/html/rfc4880#section-6.2
*/
static function footer($marker) {
return '-----END ' . strtoupper((string)$marker) . '-----';
}
/**
* @see http://tools.ietf.org/html/rfc4880#section-6
* @see http://tools.ietf.org/html/rfc4880#section-6.1
*/
static function crc24($data) {
$crc = 0x00b704ce;
for ($i = 0; $i < strlen($data); $i++) {
$crc ^= (ord($data[$i]) & 255) << 16;
for ($j = 0; $j < 8; $j++) {
$crc <<= 1;
if ($crc & 0x01000000) {
$crc ^= 0x01864cfb;
}
}
}
return $crc & 0x00ffffff;
}
/**
* @see http://tools.ietf.org/html/rfc4880#section-12.2
*/
static function bitlength($data) {
return (strlen($data) - 1) * 8 + (int)floor(log(ord($data[0]), 2)) + 1;
}
}
//////////////////////////////////////////////////////////////////////////////
// OpenPGP messages
/**
* @see http://tools.ietf.org/html/rfc4880#section-4.1
* @see http://tools.ietf.org/html/rfc4880#section-11
* @see http://tools.ietf.org/html/rfc4880#section-11.3
*/
class OpenPGP_Message implements IteratorAggregate, ArrayAccess {
public $uri = NULL;
public $packets = array();
static function parse_file($path) {
if (($msg = self::parse(file_get_contents($path)))) {
$msg->uri = preg_match('!^[\w\d]+://!', $path) ? $path : 'file://' . realpath($path);
return $msg;
}
}
/**
* @see http://tools.ietf.org/html/rfc4880#section-4.1
* @see http://tools.ietf.org/html/rfc4880#section-4.2
*/
static function parse($input) {
if (is_resource($input)) {
return self::parse_stream($input);
}
if (is_string($input)) {
return self::parse_string($input);
}
}
static function parse_stream($input) {
return self::parse_string(stream_get_contents($input));
}
static function parse_string($input) {
$msg = new self;
while (($length = strlen($input)) > 0) {
if (($packet = OpenPGP_Packet::parse($input))) {
$msg[] = $packet;
}
if ($length == strlen($input)) { // is parsing stuck?
break;
}
}
return $msg;
}
function __construct(array $packets = array()) {
$this->packets = $packets;
}
// IteratorAggregate interface
function getIterator() {
return new ArrayIterator($this->packets);
}
// ArrayAccess interface
function offsetExists($offset) {
return isset($this->packets[$offset]);
}
function offsetGet($offset) {
return $this->packets[$offset];
}
function offsetSet($offset, $value) {
return is_null($offset) ? $this->packets[] = $value : $this->packets[$offset] = $value;
}
function offsetUnset($offset) {
unset($this->packets[$offset]);
}
}
//////////////////////////////////////////////////////////////////////////////
// OpenPGP packets
/**
* OpenPGP packet.
*
* @see http://tools.ietf.org/html/rfc4880#section-4.1
* @see http://tools.ietf.org/html/rfc4880#section-4.3
*/
class OpenPGP_Packet {
public $tag, $size, $data;
static function class_for($tag) {
return isset(self::$tags[$tag]) && class_exists(
$class = 'OpenPGP_' . self::$tags[$tag] . 'Packet') ? $class : __CLASS__;
}
/**
* Parses an OpenPGP packet.
*
* @see http://tools.ietf.org/html/rfc4880#section-4.2
*/
static function parse(&$input) {
$packet = NULL;
if (strlen($input) > 0) {
$parser = ord($input[0]) & 64 ? 'parse_new_format' : 'parse_old_format';
list($tag, $head_length, $data_length) = self::$parser($input);
$input = substr($input, $head_length);
if ($tag && ($class = self::class_for($tag))) {
$packet = new $class();
$packet->tag = $tag;
$packet->input = substr($input, 0, $data_length);
$packet->length = $data_length;
$packet->read();
unset($packet->input);
}
$input = substr($input, $data_length);
}
return $packet;
}
/**
* Parses a new-format (RFC 4880) OpenPGP packet.
*
* @see http://tools.ietf.org/html/rfc4880#section-4.2.2
*/
static function parse_new_format($input) {
$tag = ord($input[0]) & 63;
// TODO
}
/**
* Parses an old-format (PGP 2.6.x) OpenPGP packet.
*
* @see http://tools.ietf.org/html/rfc4880#section-4.2.1
*/
static function parse_old_format($input) {
$len = ($tag = ord($input[0])) & 3;
$tag = ($tag >> 2) & 15;
switch ($len) {
case 0: // The packet has a one-octet length. The header is 2 octets long.
$head_length = 2;
$data_length = ord($input[1]);
break;
case 1: // The packet has a two-octet length. The header is 3 octets long.
$head_length = 3;
$data_length = unpack('n', substr($input, 1, 2));
$data_length = $data_length[1];
break;
case 2: // The packet has a four-octet length. The header is 5 octets long.
$head_length = 5;
$data_length = unpack('N', substr($input, 1, 4));
$data_length = $data_length[1];
break;
case 3: // The packet is of indeterminate length. The header is 1 octet long.
$head_length = 1;
$data_length = strlen($input) - $head_length;
break;
}
return array($tag, $head_length, $data_length);
}
function __construct() {}
function read() {
}
/**
* @see http://tools.ietf.org/html/rfc4880#section-3.5
*/
function read_timestamp() {
return $this->read_unpacked(4, 'N');
}
/**
* @see http://tools.ietf.org/html/rfc4880#section-3.2
*/
function read_mpi() {
$length = $this->read_unpacked(2, 'n'); // length in bits
$length = (int)floor(($length + 7) / 8); // length in bytes
return $this->read_bytes($length);
}
/**
* @see http://php.net/manual/en/function.unpack.php
*/
function read_unpacked($count, $format) {
$unpacked = unpack($format, $this->read_bytes($count));
return $unpacked[1];
}
function read_byte() {
return ($bytes = $this->read_bytes()) ? $bytes[0] : NULL;
}
function read_bytes($count = 1) {
$bytes = substr($this->input, 0, $count);
$this->input = substr($this->input, $count);
return $bytes;
}
static $tags = array(
1 => 'AsymmetricSessionKey', // Public-Key Encrypted Session Key
2 => 'Signature', // Signature Packet
3 => 'SymmetricSessionKey', // Symmetric-Key Encrypted Session Key Packet
4 => 'OnePassSignature', // One-Pass Signature Packet
5 => 'SecretKey', // Secret-Key Packet
6 => 'PublicKey', // Public-Key Packet
7 => 'SecretSubkey', // Secret-Subkey Packet
8 => 'CompressedData', // Compressed Data Packet
9 => 'EncryptedData', // Symmetrically Encrypted Data Packet
10 => 'Marker', // Marker Packet
11 => 'LiteralData', // Literal Data Packet
12 => 'Trust', // Trust Packet
13 => 'UserID', // User ID Packet
14 => 'PublicSubkey', // Public-Subkey Packet
17 => 'UserAttribute', // User Attribute Packet
18 => 'IntegrityProtectedData', // Sym. Encrypted and Integrity Protected Data Packet
19 => 'ModificationDetectionCode', // Modification Detection Code Packet
60 => 'Experimental', // Private or Experimental Values
61 => 'Experimental', // Private or Experimental Values
62 => 'Experimental', // Private or Experimental Values
63 => 'Experimental', // Private or Experimental Values
);
}
/**
* OpenPGP Public-Key Encrypted Session Key packet (tag 1).
*
* @see http://tools.ietf.org/html/rfc4880#section-5.1
*/
class OpenPGP_AsymmetricSessionKeyPacket extends OpenPGP_Packet {
// TODO
}
/**
* OpenPGP Signature packet (tag 2).
*
* @see http://tools.ietf.org/html/rfc4880#section-5.2
*/
class OpenPGP_SignaturePacket extends OpenPGP_Packet {
// TODO
}
/**
* OpenPGP Symmetric-Key Encrypted Session Key packet (tag 3).
*
* @see http://tools.ietf.org/html/rfc4880#section-5.3
*/
class OpenPGP_SymmetricSessionKeyPacket extends OpenPGP_Packet {
// TODO
}
/**
* OpenPGP One-Pass Signature packet (tag 4).
*
* @see http://tools.ietf.org/html/rfc4880#section-5.4
*/
class OpenPGP_OnePassSignaturePacket extends OpenPGP_Packet {
// TODO
}
/**
* OpenPGP Public-Key packet (tag 6).
*
* @see http://tools.ietf.org/html/rfc4880#section-5.5.1.1
* @see http://tools.ietf.org/html/rfc4880#section-5.5.2
* @see http://tools.ietf.org/html/rfc4880#section-11.1
* @see http://tools.ietf.org/html/rfc4880#section-12
*/
class OpenPGP_PublicKeyPacket extends OpenPGP_Packet {
public $version, $timestamp, $algorithm;
public $key, $key_id, $fingerprint;
/**
* @see http://tools.ietf.org/html/rfc4880#section-5.5.2
*/
function read() {
switch ($this->version = ord($this->read_byte())) {
case 2:
case 3:
return FALSE; // TODO
case 4:
$this->timestamp = $this->read_timestamp();
$this->algorithm = ord($this->read_byte());
$this->read_key_material();
return TRUE;
}
}
/**
* @see http://tools.ietf.org/html/rfc4880#section-5.5.2
*/
function read_key_material() {
static $key_fields = array(
1 => array('n', 'e'), // RSA
16 => array('p', 'g', 'y'), // ELG-E
17 => array('p', 'q', 'g', 'y'), // DSA
);
foreach ($key_fields[$this->algorithm] as $field) {
$this->key[$field] = $this->read_mpi();
}
$this->key_id = substr($this->fingerprint(), -8);
}
/**
* @see http://tools.ietf.org/html/rfc4880#section-12.2
* @see http://tools.ietf.org/html/rfc4880#section-3.3
*/
function fingerprint() {
switch ($this->version) {
case 2:
case 3:
return $this->fingerprint = md5($this->key['n'] . $this->key['e']);
case 4:
$material = array(
chr(0x99), pack('n', $this->length),
chr($this->version), pack('N', $this->timestamp),
chr($this->algorithm),
);
foreach ($this->key as $data) {
$material[] = pack('n', OpenPGP::bitlength($data));
$material[] = $data;
}
return $this->fingerprint = sha1(implode('', $material));
}
}
}
/**
* OpenPGP Public-Subkey packet (tag 14).
*
* @see http://tools.ietf.org/html/rfc4880#section-5.5.1.2
* @see http://tools.ietf.org/html/rfc4880#section-5.5.2
* @see http://tools.ietf.org/html/rfc4880#section-11.1
* @see http://tools.ietf.org/html/rfc4880#section-12
*/
class OpenPGP_PublicSubkeyPacket extends OpenPGP_PublicKeyPacket {
// TODO
}
/**
* OpenPGP Secret-Key packet (tag 5).
*
* @see http://tools.ietf.org/html/rfc4880#section-5.5.1.3
* @see http://tools.ietf.org/html/rfc4880#section-5.5.3
* @see http://tools.ietf.org/html/rfc4880#section-11.2
* @see http://tools.ietf.org/html/rfc4880#section-12
*/
class OpenPGP_SecretKeyPacket extends OpenPGP_PublicKeyPacket {
// TODO
}
/**
* OpenPGP Secret-Subkey packet (tag 7).
*
* @see http://tools.ietf.org/html/rfc4880#section-5.5.1.4
* @see http://tools.ietf.org/html/rfc4880#section-5.5.3
* @see http://tools.ietf.org/html/rfc4880#section-11.2
* @see http://tools.ietf.org/html/rfc4880#section-12
*/
class OpenPGP_SecretSubkeyPacket extends OpenPGP_SecretKeyPacket {
// TODO
}
/**
* OpenPGP Compressed Data packet (tag 8).
*
* @see http://tools.ietf.org/html/rfc4880#section-5.6
*/
class OpenPGP_CompressedDataPacket extends OpenPGP_Packet {
public $algorithm;
/* see http://tools.ietf.org/html/rfc4880#section-9.3 */
static $algorithms = array(0 => 'Uncompressed', 1 => 'ZIP', 2 => 'ZLIB', 3 => 'BZip2');
function read() {
$this->algorithm = ord($this->read_byte());
$this->data = $this->read_bytes($this->length);
switch($this->algorithm) {
case 0:
$this->data = OpenPGP_Message::parse($this->data);
break;
case 1:
$this->data = OpenPGP_Message::parse(gzinflate($this->data));
break;
case 2:
$this->data = OpenPGP_Message::parse(gzuncompress($this->data));
break;
case 3:
$this->data = OpenPGP_Message::parse(bzdecompress($this->data));
break;
default:
/* TODO error? */
}
if($this->data) {
$this->data = $this->data->packets;
}
}
}
/**
* OpenPGP Symmetrically Encrypted Data packet (tag 9).
*
* @see http://tools.ietf.org/html/rfc4880#section-5.7
*/
class OpenPGP_EncryptedDataPacket extends OpenPGP_Packet {
// TODO
}
/**
* OpenPGP Marker packet (tag 10).
*
* @see http://tools.ietf.org/html/rfc4880#section-5.8
*/
class OpenPGP_MarkerPacket extends OpenPGP_Packet {
// TODO
}
/**
* OpenPGP Literal Data packet (tag 11).
*
* @see http://tools.ietf.org/html/rfc4880#section-5.9
*/
class OpenPGP_LiteralDataPacket extends OpenPGP_Packet {
// TODO
}
/**
* OpenPGP Trust packet (tag 12).
*
* @see http://tools.ietf.org/html/rfc4880#section-5.10
*/
class OpenPGP_TrustPacket extends OpenPGP_Packet {
// TODO
}
/**
* OpenPGP User ID packet (tag 13).
*
* @see http://tools.ietf.org/html/rfc4880#section-5.11
* @see http://tools.ietf.org/html/rfc2822
*/
class OpenPGP_UserIDPacket extends OpenPGP_Packet {
public $name, $comment, $email;
function read() {
$this->text = $this->input;
// User IDs of the form: "name (comment) <email>"
if (preg_match('/^([^\(]+)\(([^\)]+)\)\s+<([^>]+)>$/', $this->text, $matches)) {
$this->name = trim($matches[1]);
$this->comment = trim($matches[2]);
$this->email = trim($matches[3]);
}
// User IDs of the form: "name <email>"
else if (preg_match('/^([^<]+)\s+<([^>]+)>$/', $this->text, $matches)) {
$this->name = trim($matches[1]);
$this->comment = NULL;
$this->email = trim($matches[2]);
}
// User IDs of the form: "name"
else if (preg_match('/^([^<]+)$/', $this->text, $matches)) {
$this->name = trim($matches[1]);
$this->comment = NULL;
$this->email = NULL;
}
// User IDs of the form: "<email>"
else if (preg_match('/^<([^>]+)>$/', $this->text, $matches)) {
$this->name = NULL;
$this->comment = NULL;
$this->email = trim($matches[2]);
}
}
function __toString() {
$text = array();
if ($this->name) { $text[] = $this->name; }
if ($this->comment) { $text[] = "({$this->comment})"; }
if ($this->email) { $text[] = "<{$this->email}>"; }
return implode(' ', $text);
}
}
/**
* OpenPGP User Attribute packet (tag 17).
*
* @see http://tools.ietf.org/html/rfc4880#section-5.12
* @see http://tools.ietf.org/html/rfc4880#section-11.1
*/
class OpenPGP_UserAttributePacket extends OpenPGP_Packet {
public $packets;
// TODO
}
/**
* OpenPGP Sym. Encrypted Integrity Protected Data packet (tag 18).
*
* @see http://tools.ietf.org/html/rfc4880#section-5.13
*/
class OpenPGP_IntegrityProtectedDataPacket extends OpenPGP_Packet {
// TODO
}
/**
* OpenPGP Modification Detection Code packet (tag 19).
*
* @see http://tools.ietf.org/html/rfc4880#section-5.14
*/
class OpenPGP_ModificationDetectionCodePacket extends OpenPGP_Packet {
// TODO
}
/**
* OpenPGP Private or Experimental packet (tags 60..63).
*
* @see http://tools.ietf.org/html/rfc4880#section-4.3
*/
class OpenPGP_ExperimentalPacket extends OpenPGP_Packet {}