RetroShare/libretroshare/src/pgp/pgpkeyutil.h
2012-08-14 19:31:47 +00:00

96 lines
3.4 KiB
C++

/****************************************************************
* RetroShare is distributed under the following license:
*
* Copyright (C) 2012 Cyril Soler <csoler@users.sourceforge.net>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor,
* Boston, MA 02110-1301, USA.
****************************************************************/
#pragma once
// refer to RFC4880 specif document for loading GPG public keys:
//
// 11.1: transferable public keys
// Global structure of transferable public keys
//
// - one public key packet (see 12.2)
// - zero or more revocation signatures (See signature type 5.2.1 for key signature types)
//
// - user certification signatures (0x10 or 0x13)
//
// - 5.2.2: Signature format packet
// - 5.2.3.1: signature subpacket specification
//
// - 4.3: packet tags (1 byte)
#pragma once
#include <stdint.h>
#include <string>
// This class handles GPG keys. For now we only clean them from signatures, but
// in the future, we might cache them to avoid unnecessary calls to gpgme.
//
class PGPKeyManagement
{
public:
// Create a minimal key, removing all signatures and third party info.
// Input: a clean PGP certificate (starts with "----BEGIN",
// ends with "-----END PGP PUBLIC KEY BLOCK-----"
// Output: the same certificate without signatures.
//
// Returns:
//
// true if the certificate cleaning succeeded
// false otherwise.
//
static bool createMinimalKey(const std::string& pgp_certificate,std::string& cleaned_certificate) ;
static void findLengthOfMinimalKey(const unsigned char *keydata,size_t key_len,size_t& minimal_key_len) ;
static std::string makeArmouredKey(const unsigned char *keydata,size_t key_size,const std::string& version_string) ;
// Computes the 24 bits CRC checksum necessary to all PGP data.
//
static uint32_t compute24bitsCRC(unsigned char *data,size_t len) ;
};
// This class handles the parsing of PGP packet headers under various (old and new) formats.
//
class PGPKeyParser
{
public:
static const uint8_t PGP_PACKET_TAG_PUBLIC_KEY = 6 ;
static const uint8_t PGP_PACKET_TAG_USER_ID = 13 ;
static const uint8_t PGP_PACKET_TAG_SIGNATURE = 2 ;
// These functions read and move the data pointer to the next byte after the read section.
//
static uint64_t read_KeyID(unsigned char *& data) ;
static uint32_t read_125Size(unsigned char *& data) ;
static uint32_t read_partialBodyLength(unsigned char *& data) ;
static void read_packetHeader(unsigned char *& data,uint8_t& packet_tag,uint32_t& packet_length) ;
// These functions write, and indicate how many bytes where written.
//
static uint32_t write_125Size(unsigned char *data,uint32_t size) ;
// Helper functions
//
static std::string extractRadixPartFromArmouredKey(const std::string& pgp_cert,std::string& version_string);
};