/*************************************************************************** * FragmentHeader.cc -- The FragmentHeader Class represents an IPv6 * * Hop-by-Hop extension header. * ***********************IMPORTANT NMAP LICENSE TERMS************************ * * * The Nmap Security Scanner is (C) 1996-2012 Insecure.Com LLC. Nmap is * * also a registered trademark of Insecure.Com LLC. This program is free * * software; you may redistribute and/or modify it under the terms of the * * GNU General Public License as published by the Free Software * * Foundation; Version 2 with the clarifications and exceptions described * * below. This guarantees your right to use, modify, and redistribute * * this software under certain conditions. If you wish to embed Nmap * * technology into proprietary software, we sell alternative licenses * * (contact sales@insecure.com). Dozens of software vendors already * * license Nmap technology such as host discovery, port scanning, OS * * detection, version detection, and the Nmap Scripting Engine. * * * * Note that the GPL places important restrictions on "derived works", yet * * it does not provide a detailed definition of that term. To avoid * * misunderstandings, we interpret that term as broadly as copyright law * * allows. For example, we consider an application to constitute a * * "derivative work" for the purpose of this license if it does any of the * * following: * * o Integrates source code from Nmap * * o Reads or includes Nmap copyrighted data files, such as * * nmap-os-db or nmap-service-probes. * * o Executes Nmap and parses the results (as opposed to typical shell or * * execution-menu apps, which simply display raw Nmap output and so are * * not derivative works.) * * o Integrates/includes/aggregates Nmap into a proprietary executable * * installer, such as those produced by InstallShield. * * o Links to a library or executes a program that does any of the above * * * * The term "Nmap" should be taken to also include any portions or derived * * works of Nmap, as well as other software we distribute under this * * license such as Zenmap, Ncat, and Nping. This list is not exclusive, * * but is meant to clarify our interpretation of derived works with some * * common examples. Our interpretation applies only to Nmap--we don't * * speak for other people's GPL works. * * * * If you have any questions about the GPL licensing restrictions on using * * Nmap in non-GPL works, we would be happy to help. As mentioned above, * * we also offer alternative license to integrate Nmap into proprietary * * applications and appliances. These contracts have been sold to dozens * * of software vendors, and generally include a perpetual license as well * * as providing for priority support and updates. They also fund the * * continued development of Nmap. Please email sales@insecure.com for * * further information. * * * * As a special exception to the GPL terms, Insecure.Com LLC grants * * permission to link the code of this program with any version of the * * OpenSSL library which is distributed under a license identical to that * * listed in the included docs/licenses/OpenSSL.txt file, and distribute * * linked combinations including the two. You must obey the GNU GPL in all * * respects for all of the code used other than OpenSSL. If you modify * * this file, you may extend this exception to your version of the file, * * but you are not obligated to do so. * * * * If you received these files with a written license agreement or * * contract stating terms other than the terms above, then that * * alternative license agreement takes precedence over these comments. * * * * Source is provided to this software because we believe users have a * * right to know exactly what a program is going to do before they run it. * * This also allows you to audit the software for security holes (none * * have been found so far). * * * * Source code also allows you to port Nmap to new platforms, fix bugs, * * and add new features. You are highly encouraged to send your changes * * to nmap-dev@insecure.org for possible incorporation into the main * * distribution. By sending these changes to Fyodor or one of the * * Insecure.Org development mailing lists, or checking them into the Nmap * * source code repository, it is understood (unless you specify otherwise) * * that you are offering the Nmap Project (Insecure.Com LLC) the * * unlimited, non-exclusive right to reuse, modify, and relicense the * * code. Nmap will always be available Open Source, but this is important * * because the inability to relicense code has caused devastating problems * * for other Free Software projects (such as KDE and NASM). We also * * occasionally relicense the code to third parties as discussed above. * * If you wish to specify special license conditions of your * * contributions, just say so when you send them. * * * * 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 v2.0 for more details at * * http://www.gnu.org/licenses/gpl-2.0.html , or in the COPYING file * * included with Nmap. * * * ***************************************************************************/ /* This code was originally part of the Nping tool. */ #include "FragmentHeader.h" #include /******************************************************************************/ /* CONTRUCTORS, DESTRUCTORS AND INITIALIZATION METHODS */ /******************************************************************************/ FragmentHeader::FragmentHeader() { this->reset(); } /* End of FragmentHeader constructor */ FragmentHeader::~FragmentHeader() { } /* End of FragmentHeader destructor */ /** Sets every attribute to its default value */ void FragmentHeader::reset(){ memset(&this->h, 0, sizeof(nping_ipv6_ext_fragment_hdr_t)); this->length=8; } /* End of reset() */ /******************************************************************************/ /* PacketElement:: OVERWRITTEN METHODS */ /******************************************************************************/ /** @warning This method is essential for the superclass getBinaryBuffer() * method to work. Do NOT change a thing unless you know what you're doing */ u8 *FragmentHeader::getBufferPointer(){ return (u8*)(&this->h); } /* End of getBufferPointer() */ /** Stores supplied packet in the internal buffer so the information * can be accessed using the standard get & set methods. * @warning The FragmentHeader class is able to hold a maximum of * sizeof(nping_icmpv6_hdr_t) bytes. If the supplied buffer is longer than * that, only the first 1508 bytes will be stored in the internal buffer. * @warning Supplied len MUST be at least 8 bytes (min ICMPv6 header length). * @return OP_SUCCESS on success and OP_FAILURE in case of error */ int FragmentHeader::storeRecvData(const u8 *buf, size_t len){ if(buf==NULL || lenlength=0; return OP_FAILURE; }else{ int stored_len = MIN(FRAGMENT_HEADER_LEN, len); this->reset(); /* Re-init the object, just in case the caller had used it already */ this->length=stored_len; memcpy(&(this->h), buf, stored_len); } return OP_SUCCESS; } /* End of storeRecvData() */ /* Returns a protocol identifier. This is used by packet parsing funtions * that return linked lists of PacketElement objects, to determine the protocol * the object represents. */ int FragmentHeader::protocol_id() const { return HEADER_TYPE_IPv6_FRAG; } /* End of protocol_id() */ /** Determines if the data stored in the object after an storeRecvData() call * is valid and safe to use. This mainly checks the length of the data but may * also test the value of certain protocol fields to ensure their correctness. * @return the length, in bytes, of the header, if its found to be valid or * OP_FAILURE (-1) otherwise. */ int FragmentHeader::validate(){ /* Check the object's length makes sense*/ if(this->length != FRAGMENT_HEADER_LEN){ return OP_FAILURE; } /* There is not much to check for here, since header fields may take any * value. We could certainly check the NextHeader value, but let's leave * that for the class user. */ return this->length; } /* End of validate() */ /** Prints the contents of the header and calls print() on the next protocol * header in the chain (if there is any). * @return OP_SUCCESS on success and OP_FAILURE in case of error. */ int FragmentHeader::print(FILE *output, int detail) const { fprintf(output, "Fragment[%d, %d]", this->h.nh, this->h.id); // TODO: @todo : Implement this if(this->next!=NULL){ print_separator(output, detail); next->print(output, detail); } return OP_SUCCESS; } /* End of print() */ /******************************************************************************/ /* PROTOCOL-SPECIFIC METHODS */ /******************************************************************************/ /** Set Next Header field */ int FragmentHeader::setNextHeader(u8 val){ this->h.nh = val; return OP_SUCCESS; } /* End of setNextHeader() */ /** Returns next header id */ u8 FragmentHeader::getNextHeader(){ return this->h.nh; } /* End of getNextHeader() */ /** Set Offset field */ int FragmentHeader::setOffset(u16 val){ this->h.off_res_flag[0]=(u8)(val >> 8); this->h.off_res_flag[1]=(u8)((this->h.off_res_flag[1] & 0x7) | (val & ~0x7)); return OP_SUCCESS; } /* End of setOffset() */ /** Returns fragment offset */ u16 FragmentHeader::getOffset(){ return ((this->h.off_res_flag[0] << 8) + this->h.off_res_flag[1]) & 0xfff8; } /* End of getOffset() */ /* Sets the "More Fragments" flag. */ int FragmentHeader::setM(bool m_flag){ if(m_flag) this->h.off_res_flag[1]= (u8)((this->h.off_res_flag[1] & ~0x01) | 0x01); else this->h.off_res_flag[1]= (u8)((this->h.off_res_flag[1] & ~0x1)); return OP_SUCCESS; } /* End of setM() */ /* Returns true if the "More Fragments" flag is set; false otherwise. */ bool FragmentHeader::getM(){ return (this->h.off_res_flag[1] & 0x01); } /* End of getM() */ /** Set the fragment identifier */ int FragmentHeader::setIdentification(u32 val){ this->h.id=htonl(val); return OP_SUCCESS; } /* End of setIdentification() */ /** Returns the fragment identifier*/ u32 FragmentHeader::getIdentification(){ return ntohl(this->h.id); } /* End of getIdentification.() */