From fffd213c8cba2135afda493d797c41c10354770e Mon Sep 17 00:00:00 2001 From: Othmar Gsenger Date: Sat, 12 Apr 2008 11:38:42 +0000 Subject: big svn cleanup --- src/encryptedPacket.cpp | 215 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 215 insertions(+) create mode 100644 src/encryptedPacket.cpp (limited to 'src/encryptedPacket.cpp') diff --git a/src/encryptedPacket.cpp b/src/encryptedPacket.cpp new file mode 100644 index 0000000..c0221e9 --- /dev/null +++ b/src/encryptedPacket.cpp @@ -0,0 +1,215 @@ +/* + * 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 + * + * 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 +#include +#include +#include // for std::memcpy + +#include "encryptedPacket.h" +#include "datatypes.h" +#include "log.h" + +EncryptedPacket::EncryptedPacket(u_int32_t payload_length, bool allow_realloc) + : Buffer(payload_length + sizeof(struct HeaderStruct), allow_realloc) +{ + header_ = reinterpret_cast(buf_); + payload_ = buf_ + sizeof(struct HeaderStruct); + auth_tag_ = NULL; + if(header_) + { + header_->seq_nr = 0; + header_->sender_id = 0; + header_->mux = 0; + } +} + +seq_nr_t EncryptedPacket::getSeqNr() const +{ + if(header_) + return SEQ_NR_T_NTOH(header_->seq_nr); + + return 0; +} + +sender_id_t EncryptedPacket::getSenderId() const +{ + if(header_) + return SENDER_ID_T_NTOH(header_->sender_id); + + return 0; +} + +mux_t EncryptedPacket::getMux() const +{ + if(header_) + return MUX_T_NTOH(header_->mux); + + return 0; +} + +void EncryptedPacket::setSeqNr(seq_nr_t seq_nr) +{ + if(header_) + header_->seq_nr = SEQ_NR_T_HTON(seq_nr); +} + +void EncryptedPacket::setSenderId(sender_id_t sender_id) +{ + if(header_) + header_->sender_id = SENDER_ID_T_HTON(sender_id); +} + +void EncryptedPacket::setMux(mux_t mux) +{ + if(header_) + header_->mux = MUX_T_HTON(mux); +} + +void EncryptedPacket::setHeader(seq_nr_t seq_nr, sender_id_t sender_id, mux_t mux) +{ + if(!header_) + return; + + header_->seq_nr = SEQ_NR_T_HTON(seq_nr); + header_->sender_id = SENDER_ID_T_HTON(sender_id); + header_->mux = MUX_T_HTON(mux); +} + +u_int32_t EncryptedPacket::getPayloadLength() const +{ + if(!payload_) + return 0; + + if(!auth_tag_) + return (length_ > sizeof(struct HeaderStruct)) ? (length_ - sizeof(struct HeaderStruct)) : 0; + + return (length_ > (sizeof(struct HeaderStruct) + AUTHTAG_SIZE)) ? (length_ - sizeof(struct HeaderStruct) - AUTHTAG_SIZE) : 0; +} + +void EncryptedPacket::setPayloadLength(u_int32_t payload_length) +{ + Buffer::setLength(payload_length + sizeof(struct HeaderStruct)); + // depending on allow_realloc buf_ may point to another address + // therefore in this case reinit() gets called by Buffer::setLength() +} + +void EncryptedPacket::reinit() +{ + header_ = reinterpret_cast(buf_); + payload_ = buf_ + sizeof(struct HeaderStruct); + + if(length_ <= (sizeof(struct HeaderStruct))) + payload_ = NULL; + + if(length_ < (sizeof(struct HeaderStruct))) { + header_ = NULL; + throw std::runtime_error("packet can't be initialized, buffer is too small"); + } + + if(auth_tag_) + { + if(length_ < (sizeof(struct HeaderStruct) + AUTHTAG_SIZE)) { + auth_tag_ = NULL; + throw std::runtime_error("auth-tag can't be enabled, buffer is too small"); + } + auth_tag_ = buf_ + length_ - AUTHTAG_SIZE; + } +} + +u_int8_t* EncryptedPacket::getPayload() +{ + return payload_; +} + +u_int8_t* EncryptedPacket::getAuthenticatedPortion() +{ + return buf_; +} + +u_int32_t EncryptedPacket::getAuthenticatedPortionLength() +{ + if(!buf_) + return 0; + + if(!auth_tag_) + return length_; + + return (length_ > AUTHTAG_SIZE) ? (length_ - AUTHTAG_SIZE) : 0; +} + +void EncryptedPacket::withAuthTag(bool b) +{ + if((b && auth_tag_) || (!b && !auth_tag_)) + return; + + if(b) + { + if(length_ < (sizeof(struct HeaderStruct) + AUTHTAG_SIZE)) + throw std::runtime_error("auth-tag can't be enabled, buffer is too small"); + + auth_tag_ = buf_ + length_ - AUTHTAG_SIZE; + } + else + auth_tag_ = NULL; +} + +void EncryptedPacket::addAuthTag() +{ + if(auth_tag_) + return; + + auth_tag_ = buf_; // will be set to the correct value @ reinit + setLength(length_ + AUTHTAG_SIZE); + if(auth_tag_ == buf_) // reinit was not called by setLength + reinit(); +} + +void EncryptedPacket::removeAuthTag() +{ + if(!auth_tag_) + return; + + auth_tag_ = NULL; + setLength(length_ - AUTHTAG_SIZE); +} + +u_int8_t* EncryptedPacket::getAuthTag() +{ + return auth_tag_; +} + +u_int32_t EncryptedPacket::getAuthTagLength() +{ + if(auth_tag_) + return AUTHTAG_SIZE; + + return 0; +} -- cgit v1.2.3