openpgp-php/lib/openpgp.php
2011-07-25 12:23:00 -05:00

1247 lines
37 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>
* @author Stephen Paul Weber <singpolyma@singpolyma.net>
* @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);
$text .= "\n".'=' . base64_encode(substr(pack('N', self::crc24($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;
}
function to_bytes() {
$bytes = '';
foreach($this as $p) {
$bytes .= $p->to_bytes();
}
return $bytes;
}
function signature_and_data($index=0) {
$msg = $this;
while($msg[0] instanceof OpenPGP_CompressedDataPacket) $msg = $msg[0];
$i = 0;
foreach($msg as $p) {
if($p instanceof OpenPGP_SignaturePacket) {
if($i == $index) $signature_packet = $p;
$i++;
}
if($p instanceof OpenPGP_LiteralDataPacket) $data_packet = $p;
if($signature_packet && $data_packet) break;
}
return array($signature_packet, $data_packet);
}
/**
* Function to verify signature number $index
* $verifiers is an array of callbacks formatted like array('RSA' => array('SHA256' => CALLBACK)) that take two parameters: message and signature
*/
function verify($verifiers, $index=0) {
list($signature_packet, $data_packet) = $this->signature_and_data($index);
if(!$signature_packet || !$data_packet) return NULL; // No signature or no data
$verifier = $verifiers[$signature_packet->key_algorithm_name()][$signature_packet->hash_algorithm_name()];
if(!$verifier) return NULL; // No verifier
$data_packet->normalize();
return call_user_func($verifier, $data_packet->data.$signature_packet->trailer, $signature_packet->data);
}
// IteratorAggregate interface
function getIterator() {
return new ArrayIterator($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;
$len = ord($input[1]);
if($len < 192) { // One octet length
return array($tag, 2, $len);
}
if($len > 191 && $len < 224) { // Two octet length
return array($tag, 3, (($len - 192) << 8) + ord($input[2]) + 192);
}
if($len == 255) { // Five octet length
return array($tag, 6, array_pop(unpack('N', substr($input, 2, 4))));
}
// TODO: Partial body lengths. 1 << ($len & 0x1F)
}
/**
* 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, $data_length);
}
function __construct($data=NULL) {
$this->tag = array_search(substr(substr(get_class($this), 8), 0, -6), self::$tags);
$this->data = $data;
}
function read() {
}
function body() {
return $this->data; // Will normally be overridden by subclasses
}
function header_and_body() {
$body = $this->body(); // Get body first, we will need it's length
$tag = chr($this->tag | 0xC0); // First two bits are 1 for new packet format
$size = chr(255).pack('N', strlen($body)); // Use 5-octet lengths
return array('header' => $tag.$size, 'body' => $body);
}
function to_bytes() {
$data = $this->header_and_body();
return $data['header'].$data['body'];
}
/**
* @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 {
public $version, $signature_type, $hash_algorithm, $key_algorithm, $hashed_subpackets, $unhashed_subpackets, $hash_head;
public $trailer; // This is the literal bytes that get tacked on the end of the message when verifying the signature
function __construct($data=NULL, $key_algorithm=NULL, $hash_algorithm=NULL) {
parent::__construct();
$this->version = 4; // Default to version 4 sigs
if(is_string($this->hash_algorithm = $hash_algorithm)) {
$this->hash_algorithm = array_search($this->hash_algorithm, self::$hash_algorithms);
}
if(is_string($this->key_algorithm = $key_algorithm)) {
$this->key_algorithm = array_search($this->key_algorithm, OpenPGP_PublicKeyPacket::$algorithms);
}
if($data) { // If we have any data, set up the creation time
$this->hashed_subpackets = array(new OpenPGP_SignaturePacket_SignatureCreationTimePacket(time()));
}
if($data instanceof OpenPGP_LiteralDataPacket) {
$this->signature_type = ($data->format == 'b') ? 0x00 : 0x01;
$data->normalize();
$data = $data->data;
}
$this->data = $data; // Store to-be-signed data in here until the signing happens
}
/**
* $this->data must be set to the data to sign (done by constructor)
* $signers in the same format as $verifiers for OpenPGP_Message.
*/
function sign_data($signers) {
$this->trailer = $this->body(true);
$signer = $signers[$this->key_algorithm_name()][$this->hash_algorithm_name()];
$this->data = call_user_func($signer, $this->data.$this->trailer);
$this->hash_head = array_pop(unpack('n', substr($this->data, 0, 2)));
}
function read() {
switch($this->version = ord($this->read_byte())) {
case 3:
// TODO: V3 sigs
break;
case 4:
$this->signature_type = ord($this->read_byte());
$this->key_algorithm = ord($this->read_byte());
$this->hash_algorithm = ord($this->read_byte());
$this->trailer = chr(4).chr($this->signature_type).chr($this->key_algorithm).chr($this->hash_algorithm);
$hashed_size = $this->read_unpacked(2, 'n');
$hashed_subpackets = $this->read_bytes($hashed_size);
$this->trailer .= pack('n', $hashed_size).$hashed_subpackets;
$this->hashed_subpackets = self::get_subpackets($hashed_subpackets);
$this->trailer .= chr(4).chr(0xff).pack('N', 6 + $hashed_size);
$unhashed_size = $this->read_unpacked(2, 'n');
$this->unhashed_subpackets = self::get_subpackets($this->read_bytes($unhashed_size));
$this->hash_head = $this->read_unpacked(2, 'n');
$this->data = $this->read_mpi();
break;
}
}
function body($trailer=false) {
$body = chr(4).chr($this->signature_type).chr($this->key_algorithm).chr($this->hash_algorithm);
$hashed_subpackets = '';
foreach((array)$this->hashed_subpackets as $p) {
$hashed_subpackets .= $p->to_bytes();
}
$body .= pack('n', strlen($hashed_subpackets)).$hashed_subpackets;
// The trailer is just the top of the body plus some crap
if($trailer) return $body.chr(4).chr(0xff).pack('N', strlen($body));
$unhashed_subpackets = '';
foreach((array)$this->unhashed_subpackets as $p) {
$unhashed_subpackets .= $p->to_bytes();
}
$body .= pack('n', strlen($unhashed_subpackets)).$unhashed_subpackets;
$body .= pack('n', $this->hash_head);
$body .= pack('n', OpenPGP::bitlength($this->data)).$this->data;
return $body;
}
function key_algorithm_name() {
return OpenPGP_PublicKeyPacket::$algorithms[$this->key_algorithm];
}
function hash_algorithm_name() {
return self::$hash_algorithms[$this->hash_algorithm];
}
function issuer() {
foreach($this->hashed_subpackets as $p) {
if($p instanceof OpenPGP_SignaturePacket_IssuerPacket) return $p->data;
}
foreach($this->unhashed_subpackets as $p) {
if($p instanceof OpenPGP_SignaturePacket_IssuerPacket) return $p->data;
}
return NULL;
}
/**
* @see http://tools.ietf.org/html/rfc4880#section-5.2.3.1
*/
static function get_subpackets($input) {
$subpackets = array();
while(($length = strlen($input)) > 0) {
$subpackets[] = self::get_subpacket($input);
if($length == strlen($input)) { // Parsing stuck?
break;
}
}
return $subpackets;
}
static function get_subpacket(&$input) {
$len = ord($input[0]);
$length_of_length = 1;
// if($len < 192) One octet length, no furthur processing
if($len > 190 && $len < 255) { // Two octet length
$length_of_length = 2;
$len = (($len - 192) << 8) + ord($input[1]) + 192;
}
if($len == 255) { // Five octet length
$length_of_length = 5;
$len = array_pop(unpack('N', substr($input, 1, 4)));
}
$input = substr($input, $length_of_length); // Chop off length header
$tag = ord($input[0]);
$class = self::class_for($tag);
if($class) {
$packet = new $class();
$packet->tag = $tag;
$packet->input = substr($input, 1, $len-1);
$packet->length = $len-1;
$packet->read();
unset($packet->input);
}
$input = substr($input, $len); // Chop off the data from this packet
return $packet;
}
static $hash_algorithms = array(
1 => 'MD5',
2 => 'SHA1',
3 => 'RIPEMD160',
8 => 'SHA256',
9 => 'SHA384',
10 => 'SHA512',
11 => 'SHA224'
);
static $subpacket_types = array(
//0 => 'Reserved',
//1 => 'Reserved',
2 => 'SignatureCreationTime',
3 => 'SignatureExpirationTime',
4 => 'ExportableCertification',
5 => 'TrustSignature',
6 => 'RegularExpression',
7 => 'Revocable',
//8 => 'Reserved',
9 => 'KeyExpirationTime',
//10 => 'Placeholder for backward compatibility',
11 => 'PreferredSymmetricAlgorithms',
12 => 'RevocationKey',
//13 => 'Reserved',
//14 => 'Reserved',
//15 => 'Reserved',
16 => 'Issuer',
//17 => 'Reserved',
//18 => 'Reserved',
//19 => 'Reserved',
20 => 'NotationData',
21 => 'PreferredHashAlgorithms',
22 => 'PreferredCompressionAlgorithms',
23 => 'KeyServerPreferences',
24 => 'PreferredKeyServer',
25 => 'PrimaryUserID',
26 => 'PolicyURI',
27 => 'KeyFlags',
28 => 'SignersUserID',
29 => 'ReasonforRevocation',
30 => 'Features',
31 => 'SignatureTarget',
32 => 'EmbeddedSignature',
);
static function class_for($tag) {
if(!self::$subpacket_types[$tag]) return NULL;
return 'OpenPGP_SignaturePacket_'.self::$subpacket_types[$tag].'Packet';
}
}
class OpenPGP_SignaturePacket_Subpacket extends OpenPGP_Packet {
function __construct($data=NULL) {
parent::__construct($data);
$this->tag = array_search(substr(substr(get_class($this), 8+16), 0, -6), OpenPGP_SignaturePacket::$subpacket_types);
}
function header_and_body() {
$body = $this->body(); // Get body first, we will need it's length
$size = chr(255).pack('N', strlen($body)+1); // Use 5-octet lengths + 1 for tag as first packet body octet
$tag = chr($this->tag);
return array('header' => $size.$tag, 'body' => $body);
}
}
/**
* @see http://tools.ietf.org/html/rfc4880#section-5.2.3.4
*/
class OpenPGP_SignaturePacket_SignatureCreationTimePacket extends OpenPGP_SignaturePacket_Subpacket {
function read() {
$this->data = $this->read_timestamp();
}
function body() {
return pack('N', $this->data);
}
}
class OpenPGP_SignaturePacket_SignatureExpirationTimePacket extends OpenPGP_SignaturePacket_Subpacket {
function read() {
$this->data = $this->read_timestamp();
}
function body() {
return pack('N', $this->data);
}
}
class OpenPGP_SignaturePacket_ExportableCertificationPacket extends OpenPGP_SignaturePacket_Subpacket {
// TODO
}
class OpenPGP_SignaturePacket_TrustSignaturePacket extends OpenPGP_SignaturePacket_Subpacket {
// TODO
}
class OpenPGP_SignaturePacket_RegularExpressionPacket extends OpenPGP_SignaturePacket_Subpacket {
// TODO
}
class OpenPGP_SignaturePacket_RevocablePacket extends OpenPGP_SignaturePacket_Subpacket {
// TODO
}
class OpenPGP_SignaturePacket_KeyExpirationTimePacket extends OpenPGP_SignaturePacket_Subpacket {
function read() {
$this->data = $this->read_timestamp();
}
function body() {
return pack('N', $this->data);
}
}
class OpenPGP_SignaturePacket_PreferredSymmetricAlgorithmsPacket extends OpenPGP_SignaturePacket_Subpacket {
// TODO
}
class OpenPGP_SignaturePacket_RevocationKeyPacket extends OpenPGP_SignaturePacket_Subpacket {
// TODO
}
/**
* @see http://tools.ietf.org/html/rfc4880#section-5.2.3.5
*/
class OpenPGP_SignaturePacket_IssuerPacket extends OpenPGP_SignaturePacket_Subpacket {
function read() {
for($i = 0; $i < 8; $i++) { // Store KeyID in Hex
$this->data .= sprintf('%02X',ord($this->read_byte()));
}
}
function body() {
$bytes = '';
for($i = 0; $i < strlen($this->data); $i += 2) {
$bytes .= chr(hexdec($this->data{$i}.$this->data{$i+1}));
}
return $bytes;
}
}
class OpenPGP_SignaturePacket_NotationDataPacket extends OpenPGP_SignaturePacket_Subpacket {
// TODO
}
class OpenPGP_SignaturePacket_PreferredHashAlgorithmsPacket extends OpenPGP_SignaturePacket_Subpacket {
// TODO
}
class OpenPGP_SignaturePacket_PreferredCompressionAlgorithmsPacket extends OpenPGP_SignaturePacket_Subpacket {
// TODO
}
class OpenPGP_SignaturePacket_KeyServerPreferencesPacket extends OpenPGP_SignaturePacket_Subpacket {
// TODO
}
class OpenPGP_SignaturePacket_PreferredKeyServerPacket extends OpenPGP_SignaturePacket_Subpacket {
// TODO
}
class OpenPGP_SignaturePacket_PrimaryUserIDPacket extends OpenPGP_SignaturePacket_Subpacket {
// TODO
}
class OpenPGP_SignaturePacket_PolicyURIPacket extends OpenPGP_SignaturePacket_Subpacket {
// TODO
}
class OpenPGP_SignaturePacket_KeyFlagsPacket extends OpenPGP_SignaturePacket_Subpacket {
function __construct($flags=array()) {
parent::__construct();
$this->flags = $flags;
}
function read() {
$this->flags = array();
while($this->input) {
$this->flags[] = ord($this->read_byte());
}
}
function body() {
$bytes = '';
foreach($this->flags as $f) {
$bytes .= chr($f);
}
return $bytes;
}
}
class OpenPGP_SignaturePacket_SignersUserIDPacket extends OpenPGP_SignaturePacket_Subpacket {
// TODO
}
class OpenPGP_SignaturePacket_ReasonforRevocationPacket extends OpenPGP_SignaturePacket_Subpacket {
// TODO
}
class OpenPGP_SignaturePacket_FeaturesPacket extends OpenPGP_SignaturePacket_KeyFlagsPacket {
// Identical functionality to parent
}
class OpenPGP_SignaturePacket_SignatureTargetPacket extends OpenPGP_SignaturePacket_Subpacket {
// TODO
}
class OpenPGP_SignaturePacket_EmbeddedSignaturePacket extends OpenPGP_SignaturePacket {
// TODO: This is duplicated from subpacket... improve?
function __construct($data=NULL) {
parent::__construct($data);
$this->tag = array_search(substr(substr(get_class($this), 8+16), 0, -6), OpenPGP_SignaturePacket::$subpacket_types);
}
function header_and_body() {
$body = $this->body(); // Get body first, we will need it's length
$size = chr(255).pack('N', strlen($body)+1); // Use 5-octet lengths + 1 for tag as first packet body octet
$tag = chr($this->tag);
return array('header' => $size.$tag, 'body' => $body);
}
}
/**
* 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 {
public $version, $signature_type, $hash_algorithm, $key_algorithm, $key_id, $nested;
function read() {
$this->version = ord($this->read_byte());
$this->signature_type = ord($this->read_byte());
$this->hash_algorithm = ord($this->read_byte());
$this->key_algorithm = ord($this->read_byte());
for($i = 0; $i < 8; $i++) { // Store KeyID in Hex
$this->key_id .= sprintf('%02X',ord($this->read_byte()));
}
$this->nested = ord($this->read_byte());
}
function body() {
$body = chr($this->version).chr($this->signature_type).chr($this->hash_algorithm).chr($this->key_algorithm);
for($i = 0; $i < strlen($this->key_id); $i += 2) {
$body .= chr(hexdec($this->key_id{$i}.$this->key_id{$i+1}));
}
$body .= chr((int)$this->nested);
return $body;
}
}
/**
* 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, $fingerprint;
// Find self signatures in a message, these often contain metadata about the key
function self_signatures($message) {
$sigs = array();
$keyid16 = strtoupper(substr($this->fingerprint, -16));
foreach($message as $p) {
if($p instanceof OpenPGP_SignaturePacket) {
if(strtoupper($p->issuer()) == $keyid16) {
$sigs[] = $p;
} else {
foreach(array_merge($p->hashed_subpackets, $p->unhashed_subpackets) as $s) {
if($s instanceof OpenPGP_SignaturePacket_EmbeddedSignaturePacket && strtoupper($s->issuer()) == $keyid16) {
$sigs[] = $p;
break;
}
}
}
} else if(count($sigs)) break; // After we've seen a self sig, the next non-sig stop all self-sigs
}
return $sigs;
}
// Find expiry time of this key based on the self signatures in a message
function expires($message) {
foreach($this->self_signatures($message) as $p) {
foreach(array_merge($p->hashed_subpackets, $p->unhashed_subpackets) as $s) {
if($s instanceof OpenPGP_SignaturePacket_KeyExpirationTimePacket) {
return $this->timestamp + $s->data;
}
}
}
return NULL; // Never expires
}
/**
* @see http://tools.ietf.org/html/rfc4880#section-5.5.2
*/
function read() {
switch ($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());
$this->read_key_material();
return TRUE;
}
}
/**
* @see http://tools.ietf.org/html/rfc4880#section-5.5.2
*/
function read_key_material() {
foreach (self::$key_fields[$this->algorithm] as $field) {
$this->key[$field] = $this->read_mpi();
}
$this->key_id = substr($this->fingerprint(), -8);
}
function fingerprint_material() {
switch ($this->version) {
case 2:
case 3:
return array($this->key['n'], $this->key['e']);
case 4:
$head = array(
chr(0x99), NULL,
chr($this->version), pack('N', $this->timestamp),
chr($this->algorithm),
);
$material = array();
foreach (self::$key_fields[$this->algorithm] as $i) {
$material[] = pack('n', OpenPGP::bitlength($this->key[$i]));
$material[] = $this->key[$i];
}
$material = implode('', $material);
$head[1] = pack('n', 6 + strlen($material));
$head[] = $material;
return $head;
}
}
/**
* @see http://tools.ietf.org/html/rfc4880#section-12.2
* @see http://tools.ietf.org/html/rfc4880#section-3.3
*/
function fingerprint() {
switch ($this->version) {
case 2:
case 3:
return md5(implode('', $this->fingerprint_material()));
case 4:
return sha1(implode('', $this->fingerprint_material()));
}
}
function body() {
switch ($this->version) {
case 2:
case 3:
/* TODO */
case 4:
return implode('', array_slice($this->fingerprint_material(), 2));
}
}
static $key_fields = array(
1 => array('n', 'e'), // RSA
16 => array('p', 'g', 'y'), // ELG-E
17 => array('p', 'q', 'g', 'y'), // DSA
);
static $algorithms = array(
1 => 'RSA',
2 => 'RSA',
3 => 'RSA',
16 => 'ELGAMAL',
17 => 'DSA',
18 => 'ECC',
19 => 'ECDSA',
21 => 'DH'
);
}
/**
* 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 {
public $s2k_useage, $s2k_type, $s2k_hash_algorithm, $s2k_salt, $s2k_count, $symmetric_type, $private_hash, $encrypted_data;
function read() {
parent::read(); // All the fields from PublicKey
$this->s2k_useage = ord($this->read_byte());
if($this->s2k_useage == 255 || $this->s2k_useage == 254) {
$this->symmetric_type = ord($this->read_byte());
$this->s2k_type = ord($this->read_byte());
$this->s2k_hash_algorithm = ord($this->read_byte());
if($this->s2k_type == 1 || $this->s2k_type == 3) $this->s2k_salt = $this->read_bytes(8);
if($this->s2k_type == 3) {
$c = ord($this->read_byte());
$this->s2k_count = ((int)16 + ($c & 15)) << (($c >> 4) + 6);
}
} else if($this->s2k_useage > 0) {
$this->symmetric_type = $this->s2k_useage;
}
if($this->s2k_useage > 0) {
// TODO: IV of the same length as cipher's block size
$this->encrypted_data = $this->input; // Rest of input is MPIs and checksum (encrypted)
} else {
$this->data = $this->input; // Rest of input is MPIs and checksum
$this->key_from_data();
}
}
function key_from_data() {
if(!$this->data) return NULL; // Not decrypted yet
$this->input = $this->data;
static $key_fields = array(
1 => array('d', 'p', 'q', 'u'), // RSA
16 => array('x'), // ELG-E
17 => array('x'), // DSA
);
foreach($key_fields[$this->algorithm] as $field) {
$this->key[$field] = $this->read_mpi();
}
// TODO: Validate checksum?
if($this->s2k_useage == 254) { // 20 octet sha1 hash
$this->private_hash = $this->read_bytes(20);
} else { // two-octet checksum
$this->private_hash = $this->read_bytes(2);
}
unset($this->input);
}
}
/**
* 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 implements IteratorAggregate, ArrayAccess {
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? */
}
}
function body() {
$body = chr($this->algorithm);
switch($this->algorithm) {
case 0:
$body .= $this->data->to_bytes();
break;
case 1:
$body .= gzdeflate($this->data->to_bytes());
break;
case 2:
$body .= gzcompress($this->data->to_bytes());
break;
case 3:
$body .= bzcompress($this->data->to_bytes());
break;
default:
/* TODO error? */
}
return $body;
}
// IteratorAggregate interface
function getIterator() {
return new ArrayIterator($this->data->packets);
}
// ArrayAccess interface
function offsetExists($offset) {
return isset($this->data[$offset]);
}
function offsetGet($offset) {
return $this->data[$offset];
}
function offsetSet($offset, $value) {
return is_null($offset) ? $this->data[] = $value : $this->data[$offset] = $value;
}
function offsetUnset($offset) {
unset($this->data[$offset]);
}
}
/**
* 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 {
public $format, $filename, $timestamp;
function __construct($data=NULL, $opt=array()) {
parent::__construct();
$this->data = $data;
$this->format = $opt['format'] ? $opt['format'] : 'b';
$this->filename = $opt['filename'] ? $opt['filename'] : 'data';
$this->timestamp = $opt['timestamp'] ? $opt['timestamp'] : time();
}
function normalize() {
if($this->format == 'u' || $this->format == 't') { // Normalize line endings
$this->data = str_replace("\n", "\r\n", str_replace("\r", "\n", str_replace("\r\n", "\n", $this->data)));
}
}
function read() {
$this->size = $this->length - 1 - 4;
$this->format = $this->read_byte();
$filename_length = ord($this->read_byte());
$this->size -= $filename_length;
$this->filename = $this->read_bytes($filename_length);
$this->timestamp = $this->read_timestamp();
$this->data = $this->read_bytes($this->size);
}
function body() {
return $this->format.chr(strlen($this->filename)).$this->filename.pack('N', $this->timestamp).$this->data;
}
}
/**
* 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 {}