diff options
Diffstat (limited to 'encryptedPacket.cpp')
| -rw-r--r-- | encryptedPacket.cpp | 287 |
1 files changed, 287 insertions, 0 deletions
diff --git a/encryptedPacket.cpp b/encryptedPacket.cpp new file mode 100644 index 0000000..0ac0ca9 --- /dev/null +++ b/encryptedPacket.cpp @@ -0,0 +1,287 @@ +/* + * anytun + * + * The secure anycast tunneling protocol (satp) defines a protocol used + * for communication between any combination of unicast and anycast + * tunnel endpoints. It has less protocol overhead than IPSec in Tunnel + * mode and allows tunneling of every ETHER TYPE protocol (e.g. + * ethernet, ip, arp ...). satp directly includes cryptography and + * message authentication based on the methodes used by SRTP. It is + * intended to deliver a generic, scaleable and secure solution for + * tunneling and relaying of packets of any protocol. + * + * + * Copyright (C) 2007 anytun.org <satp@wirdorange.org> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 + * as published by the Free Software Foundation. + * + * 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 (see the file COPYING included with this + * distribution); if not, write to the Free Software Foundation, Inc., + * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#include <stdexcept> +#include <iostream> +#include <arpa/inet.h> +#include <cstdio> // for std::memcpy + +#include "encryptedPacket.h" +#include "datatypes.h" +#include "authTag.h" +#include "log.h" + + +EncryptedPacket::EncryptedPacket(u_int32_t max_payload_length) + : Buffer(max_payload_length + sizeof(struct HeaderStruct) + AUTHTAG_SIZE) +{ + header_ = reinterpret_cast<struct HeaderStruct*>(buf_); + auth_tag_ = NULL; + buf_ = buf_ + sizeof(struct HeaderStruct); // no authtag yet + length_ = length_ - sizeof(struct HeaderStruct); + size_ = max_payload_length + AUTHTAG_SIZE; +} + + +seq_nr_t EncryptedPacket::getSeqNr() const +{ + return SEQ_NR_T_NTOH(header_->seq_nr); +} + +sender_id_t EncryptedPacket::getSenderId() const +{ + return SENDER_ID_T_NTOH(header_->sender_id); +} + +mux_t EncryptedPacket::getMux() const +{ + return MUX_T_NTOH(header_->mux); +} + +u_int32_t EncryptedPacket::getSize() const +{ + return size_; +} + +void EncryptedPacket::setLength(u_int32_t length) +{ + if(length > size_) + throw std::out_of_range("can't set length greater then size ofsize of allocated memory"); + + length_ = length; +} + +void EncryptedPacket::setSeqNr(seq_nr_t seq_nr) +{ + header_->seq_nr = SEQ_NR_T_HTON(seq_nr); +} + +void EncryptedPacket::setSenderId(sender_id_t sender_id) +{ + header_->sender_id = SENDER_ID_T_HTON(sender_id); +} + +void EncryptedPacket::setMux(mux_t mux) +{ + header_->mux = MUX_T_HTON(mux); +} + +void EncryptedPacket::setHeader(seq_nr_t seq_nr, sender_id_t sender_id, mux_t mux) +{ + header_->seq_nr = SEQ_NR_T_HTON(seq_nr); + header_->sender_id = SENDER_ID_T_HTON(sender_id); + header_->mux = MUX_T_HTON(mux); +} + +bool EncryptedPacket::hasAuthTag() const +{ + if( auth_tag_ == NULL ) + return false; + return true; +} + +void EncryptedPacket::withAuthTag(bool b) +{ + if( b && (auth_tag_ != NULL) ) + throw std::runtime_error("packet already has auth tag function enabled"); + + if( b ) { + auth_tag_ = reinterpret_cast<AuthTag*>( buf_ + sizeof(struct HeaderStruct) ); + buf_ = buf_ + AUTHTAG_SIZE; + length_ -= AUTHTAG_SIZE; + size_ -= AUTHTAG_SIZE; + } else { + buf_ = reinterpret_cast<u_int8_t*>( auth_tag_ ); + length_ += AUTHTAG_SIZE; + size_ += AUTHTAG_SIZE; + auth_tag_ = NULL; + } +} + +void EncryptedPacket::setAuthTag(AuthTag& tag) +{ + if( auth_tag_ == NULL ) + throw std::runtime_error("auth tag not enabled"); + + if( tag == AuthTag(0) ) + return; + + if( tag.getLength() != AUTHTAG_SIZE ) + throw std::length_error("authtag length mismatch with AUTHTAG_SIZE"); + + std::memcpy( auth_tag_, tag.getBuf(), AUTHTAG_SIZE ); +} + +AuthTag EncryptedPacket::getAuthTag() const +{ + if( auth_tag_ == NULL ) + throw std::runtime_error("auth tag not enabled"); + + AuthTag at(AUTHTAG_SIZE); + std::memcpy(at, auth_tag_, AUTHTAG_SIZE ); + return at; +} + + +//Packet& Packet::addHeader(seq_nr_t seq_nr, sender_id_t sender_id) +//{ +// if(!has_header_) +// { +// if(sizeof(struct HeaderStruct) > resizeFront(length_ + sizeof(struct HeaderStruct))) +// return *this; +// +// has_header_ = true; +// } +// struct HeaderStruct* header; +// header = reinterpret_cast<struct HeaderStruct*>(buf_); +// header->seq_nr = SEQ_NR_T_HTON(seq_nr); +// header->sender_id = SENDER_ID_T_HTON(sender_id); +// return *this; +//} +// +// +//bool Packet::hasPayloadType() const +//{ +// return has_payload_type_; +//} +// +//Packet& Packet::withPayloadType(bool b) +//{ +// if(b && length_ >= sizeof(payload_type_t)) +// has_payload_type_ = true; +// else +// has_payload_type_ = false; +// +// return *this; +//} +// +//payload_type_t Packet::getPayloadType() const +//{ +// if(!has_payload_type_) +// return 0; +// +// if((!has_auth_tag_ && length_ < sizeof(payload_type_t)) || +// (has_auth_tag_ && length_ < (sizeof(payload_type_t) + AUTHTAG_SIZE))) +// return 0; +// +// payload_type_t* payload_type; +// +// if(!has_auth_tag_) +// payload_type = reinterpret_cast<payload_type_t*>(buf_ + length_ - sizeof(payload_type_t)); +// else +// payload_type = reinterpret_cast<payload_type_t*>(buf_ + length_ - sizeof(payload_type_t) - AUTHTAG_SIZE); +// return PAYLOAD_TYPE_T_NTOH(*payload_type); +//} +// +//Packet& Packet::addPayloadType(payload_type_t payload_type) +//{ +// if(has_auth_tag_) +// throw std::runtime_error("can't add payload_type with existing auth_tag"); +// +// if(!has_payload_type_) +// { +// u_int32_t new_length = length_ + sizeof(payload_type_t); +// if(new_length > resizeBack(new_length)) +// return *this; +// +// has_payload_type_ = true; +// } +// payload_type_t* payload_type_ptr; +// payload_type_ptr = reinterpret_cast<payload_type_t*>(buf_ + length_ - sizeof(payload_type_t)); +// *payload_type_ptr = PAYLOAD_TYPE_T_HTON(payload_type); +// return *this; +//} +// +//Packet& Packet::removePayloadType() +//{ +// if(has_auth_tag_) +// throw std::runtime_error("can't remove payload_type with existing auth_tag"); +// +// if(!has_payload_type_) +// return *this; +// +// if(length_ >= sizeof(payload_type_t)) +// resizeBack(length_ - sizeof(payload_type_t)); +// +// has_payload_type_ = false; +// +// return *this; +//} +// +// +// +// +//AuthTag Packet::getAuthTag() const +//{ +// if(!has_auth_tag_) +// return AuthTag(0); +// +// if(length_ < AUTHTAG_SIZE) +// return AuthTag(0); +// +// //AuthTag* auth_tag; +// //auth_tag = reinterpret_cast<AuthTag*>(buf_ + length_ - AUTHTAG_SIZE); +// //return AUTH_TAG_T_NTOH(*auth_tag); +// AuthTag auth_tag; +// auth_tag = AuthTag(buf_ + length_ - AUTHTAG_SIZE, AUTHTAG_SIZE); +// return auth_tag; +//} +// +//Packet& Packet::addAuthTag(AuthTag auth_tag) +//{ +// if(!has_auth_tag_) +// { +// u_int32_t new_length = length_ + auth_tag.getLength(); +// if(new_length > resizeBack(new_length)) +// return *this; +// +// has_auth_tag_ = true; +// } +// +// AuthTag* auth_tag_ptr; +// auth_tag_ptr = reinterpret_cast<AuthTag*>(buf_ + length_ - auth_tag.getLength()); +// std::memcpy(auth_tag_ptr, auth_tag.getBuf(), auth_tag.getLength()); +// +// return *this; +//} +// +//Packet& Packet::removeAuthTag() +//{ +// if(!has_auth_tag_) +// return *this; +// +// if(length_ >= AUTHTAG_SIZE) +// resizeBack(length_ - AUTHTAG_SIZE); +// +// has_auth_tag_ = false; +// +// return *this; +//} +// |