/*************************************************************************** * EthernetHeader.cc -- The EthernetHeader Class represents an Ethernet * * header and footer. It contains methods to set the different header * * fields. These methods tipically perform the necessary error checks and * * byte order conversions. * * * ***********************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 "EthernetHeader.h" /******************************************************************************/ /* CONTRUCTORS, DESTRUCTORS AND INITIALIZATION METHODS */ /******************************************************************************/ EthernetHeader::EthernetHeader(){ this->reset(); } /* End of EthernetHeader constructor */ EthernetHeader::~EthernetHeader(){ } /* End of EthernetHeader destructor */ /** Sets every attribute to its default value */ void EthernetHeader::reset(){ memset(&this->h, 0, sizeof(nping_eth_hdr_t)); this->length=ETH_HEADER_LEN; } /* End of reset() */ /** @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 * EthernetHeader::getBufferPointer(){ return (u8*)(&h); } /* End of getBufferPointer() */ /******************************************************************************/ /* PacketElement:: OVERWRITTEN METHODS */ /******************************************************************************/ /** Stores supplied packet in the internal buffer so the information * can be accessed using the standard get & set methods. * @warning The EthernetHeader class is able to hold a maximum of 14 bytes. * If the supplied buffer is longer than that, only the first 14 bytes will be * stored in the internal buffer. * @warning Supplied len MUST be at least 14 bytes (Ethernet header length). * @return OP_SUCCESS on success and OP_FAILURE in case of error */ int EthernetHeader::storeRecvData(const u8 *buf, size_t len){ if(buf==NULL || lenreset(); /* Re-init the object, just in case the caller had used it already */ this->length=ETH_HEADER_LEN; memcpy(&(this->h), buf, ETH_HEADER_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 EthernetHeader::protocol_id() const { return HEADER_TYPE_ETHERNET; } /* 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 EthernetHeader::validate(){ if( this->length!=ETH_HEADER_LEN) return OP_FAILURE; else return ETH_HEADER_LEN; } /* 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 EthernetHeader::print(FILE *output, int detail) const { fprintf(output, "Eth["); for(int i=0; i<6; i++){ fprintf(output, "%02x", this->h.eth_smac[i]); if(i<5) fprintf(output, ":"); } fprintf(output, " > "); for(int i=0; i<6; i++){ fprintf(output, "%02x", this->h.eth_dmac[i]); if(i<5) fprintf(output, ":"); } if(detail>=PRINT_DETAIL_MED) fprintf(output, " Type=%04x", this->getEtherType()); fprintf(output, "]"); if(this->next!=NULL){ print_separator(output, detail); next->print(output, detail); } return OP_SUCCESS; } /* End of print() */ /******************************************************************************/ /* PROTOCOL-SPECIFIC METHODS */ /******************************************************************************/ /** Sets Source MAC address * @warning Supplied buffer must contain at least 6 bytes */ int EthernetHeader::setSrcMAC(const u8 *m){ if(m==NULL) netutil_fatal("EthernetHeader::setSrcMAC(u8*): NULL value supplied "); memcpy(h.eth_smac, m, 6); return OP_SUCCESS; } /* End of setSrcMAC() */ /** Returns source port in HOST byte order * @warning Returned pointer points directly to a Class internal buffer. If * contents are changed, the instance of the class will be affected. */ const u8* EthernetHeader::getSrcMAC() const { return this->h.eth_smac; } /* End of getSrcMAC() */ /** Sets Destination MAC address * @warning Supplied buffer must contain at least 6 bytes */ int EthernetHeader::setDstMAC(u8 *m){ if(m==NULL) netutil_fatal("EthernetHeader::setDstMAC(u8 *): NULL value supplied "); memcpy(h.eth_dmac, m, 6); return OP_SUCCESS; } /* End of setDstMAC() */ /** Returns destination port in HOST byte order */ const u8 *EthernetHeader::getDstMAC() const { return this->h.eth_dmac; } /* End of getDstMAC() */ int EthernetHeader::setEtherType(u16 val){ h.eth_type=htons(val); return OP_SUCCESS; } /* End of setEtherType() */ /** Returns destination port in HOST byte order */ const u16 EthernetHeader::getEtherType() const { return ntohs(this->h.eth_type); } /* End of getEtherType() */