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Diffstat (limited to '')
-rw-r--r-- | libnetutil/IPv6Header.cc | 505 |
1 files changed, 505 insertions, 0 deletions
diff --git a/libnetutil/IPv6Header.cc b/libnetutil/IPv6Header.cc new file mode 100644 index 0000000..8035a98 --- /dev/null +++ b/libnetutil/IPv6Header.cc @@ -0,0 +1,505 @@ +/*************************************************************************** + * IPv6Header.cc -- The IPv6Header Class represents an IPv4 datagram. It * + * contains methods to set any header field. In general, these methods do * + * error checkings and byte order conversion. * + * * + ***********************IMPORTANT NMAP LICENSE TERMS************************ + * + * The Nmap Security Scanner is (C) 1996-2023 Nmap Software LLC ("The Nmap + * Project"). Nmap is also a registered trademark of the Nmap Project. + * + * This program is distributed under the terms of the Nmap Public Source + * License (NPSL). The exact license text applying to a particular Nmap + * release or source code control revision is contained in the LICENSE + * file distributed with that version of Nmap or source code control + * revision. More Nmap copyright/legal information is available from + * https://nmap.org/book/man-legal.html, and further information on the + * NPSL license itself can be found at https://nmap.org/npsl/ . This + * header summarizes some key points from the Nmap license, but is no + * substitute for the actual license text. + * + * Nmap is generally free for end users to download and use themselves, + * including commercial use. It is available from https://nmap.org. + * + * The Nmap license generally prohibits companies from using and + * redistributing Nmap in commercial products, but we sell a special Nmap + * OEM Edition with a more permissive license and special features for + * this purpose. See https://nmap.org/oem/ + * + * If you have received a written Nmap license agreement or contract + * stating terms other than these (such as an Nmap OEM license), you may + * choose to use and redistribute Nmap under those terms instead. + * + * The official Nmap Windows builds include the Npcap software + * (https://npcap.com) for packet capture and transmission. It is under + * separate license terms which forbid redistribution without special + * permission. So the official Nmap Windows builds may not be redistributed + * without special permission (such as an Nmap OEM license). + * + * 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. + * + * Source code also allows you to port Nmap to new platforms, fix bugs, and add + * new features. You are highly encouraged to submit your changes as a Github PR + * or by email to the dev@nmap.org mailing list for possible incorporation into + * the main distribution. Unless you specify otherwise, it is understood that + * you are offering us very broad rights to use your submissions as described in + * the Nmap Public Source License Contributor Agreement. This is important + * because we fund the project by selling licenses with various terms, and also + * because the inability to relicense code has caused devastating problems for + * other Free Software projects (such as KDE and NASM). + * + * The free version of Nmap 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. Warranties, + * indemnification and commercial support are all available through the + * Npcap OEM program--see https://nmap.org/oem/ + * + ***************************************************************************/ +/* This code was originally part of the Nping tool. */ + +#include "IPv6Header.h" + +/******************************************************************************/ +/* CONTRUCTORS, DESTRUCTORS AND INITIALIZATION METHODS */ +/******************************************************************************/ +IPv6Header::IPv6Header() { + this->reset(); +} /* End of IPv6Header constructor */ + + +IPv6Header::~IPv6Header() { + +} /* End of IPv6Header destructor */ + + +/** Sets every attribute to its default value */ +void IPv6Header::reset(){ + memset(&this->h, 0, sizeof(nping_ipv6_hdr_t)); + this->length=IPv6_HEADER_LEN; + this->setVersion(); + this->setTrafficClass(IPv6_DEFAULT_TCLASS); + this->setFlowLabel(IPv6_DEFAULT_FLABEL); + this->setHopLimit(IPv6_DEFAULT_HOPLIM); + this->setNextHeader(IPv6_DEFAULT_NXTHDR); /* No next header */ + this->setPayloadLength(0); +} /* 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 *IPv6Header::getBufferPointer(){ + return (u8*)(&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 IPv6Header class is able to hold a maximum of 40 bytes. If the + * supplied buffer is longer than that, only the first 40 bytes will be stored + * in the internal buffer. + * @warning Supplied len MUST be at least 40 bytes (IPv6 header length). + * @return OP_SUCCESS on success and OP_FAILURE in case of error */ +int IPv6Header::storeRecvData(const u8 *buf, size_t len){ + if(buf==NULL || len<IPv6_HEADER_LEN){ + return OP_FAILURE; + }else{ + this->reset(); /* Re-init the object, just in case the caller had used it already */ + this->length=IPv6_HEADER_LEN; + memcpy(&(this->h), buf, IPv6_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 IPv6Header::protocol_id() const { + return HEADER_TYPE_IPv6; +} /* 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 IPv6Header::validate(){ + if( this->length!=IPv6_HEADER_LEN) + return OP_FAILURE; + else + return IPv6_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 IPv6Header::print(FILE *output, int detail) const { + static char ipstring[256]; + memset(ipstring, 0, 256); + struct in6_addr addr; + char ipinfo[512] = ""; /* Temp info about IP. */ + + fprintf(output, "IPv6["); + this->getSourceAddress(&addr); + inet_ntop(AF_INET6, &addr, ipstring, sizeof(ipstring)); + fprintf(output, "%s", ipstring); + fprintf(output, " >"); + this->getDestinationAddress(&addr); + inet_ntop(AF_INET6, &addr, ipstring, sizeof(ipstring)); + fprintf(output, " %s", ipstring); + + /* Create a string with information relevant to the specified level of detail */ + if( detail == PRINT_DETAIL_LOW ){ + Snprintf(ipinfo, sizeof(ipinfo), "hlim=%d", this->getHopLimit()); + }else if( detail == PRINT_DETAIL_MED ){ + Snprintf(ipinfo, sizeof(ipinfo), "hlim=%d tclass=%d flow=%d", + this->getHopLimit(), this->getTrafficClass(), this->getFlowLabel() ); + }else if( detail>=PRINT_DETAIL_HIGH ){ + Snprintf(ipinfo, sizeof(ipinfo), "ver=%d hlim=%d tclass=%d flow=%d plen=%d nh=%d", + this->getVersion(), this->getHopLimit(), this->getTrafficClass(), + this->getFlowLabel(), this->getPayloadLength(), this->getNextHeader() ); + } + fprintf(output, " %s]", ipinfo); + if(this->next!=NULL){ + print_separator(output, detail); + next->print(output, detail); + } + return OP_SUCCESS; +} /* End of print() */ + + +/******************************************************************************/ +/* PROTOCOL-SPECIFIC METHODS */ +/******************************************************************************/ + +/** Set Version field (4 bits). */ +int IPv6Header::setVersion(u8 val){ + union{ + struct firstbyte{ + #if WORDS_BIGENDIAN + u8 ver:4; + u8 tclass:4; + #else + u8 tclass:4; + u8 ver:4; + #endif + }halfbyte; + u8 fullbyte; + }header1stbyte; + + header1stbyte.fullbyte = h.ip6_start[0]; + header1stbyte.halfbyte.ver=val; + h.ip6_start[0]=header1stbyte.fullbyte; + return OP_SUCCESS; +} /* End of setVersion() */ + + +/** Set Version field to value 6. */ +int IPv6Header::setVersion(){ + this->setVersion(6); + return OP_SUCCESS; +} /* End of setVersion() */ + + +/** Returns an 8bit number containing the value of the Version field. */ +u8 IPv6Header::getVersion() const { + union{ + struct firstbyte{ + #if WORDS_BIGENDIAN + u8 ver:4; + u8 tclass:4; + #else + u8 tclass:4; + u8 ver:4; + #endif + }halfbyte; + u8 fullbyte; + }header1stbyte; + + header1stbyte.fullbyte = h.ip6_start[0]; + return (u8)header1stbyte.halfbyte.ver; +} /* End of getVersion() */ + + +int IPv6Header::setTrafficClass(u8 val){ + union{ + struct firstbyte{ + #if WORDS_BIGENDIAN + u8 ver:4; + u8 tclass1:4; + #else + u8 tclass1:4; + u8 ver:4; + #endif + }halfbyte; + u8 fullbyte; + }header1stbyte; + union{ + struct firstbyte{ + #if WORDS_BIGENDIAN + u8 tclass2:4; + u8 flow:4; + #else + u8 flow:4; + u8 tclass2:4; + #endif + }halfbyte; + u8 fullbyte; + }header2ndbyte; + + /* Store old contents */ + header1stbyte.fullbyte = h.ip6_start[0]; + header2ndbyte.fullbyte = h.ip6_start[1]; + + /* Fill the two 4bit halves */ + header1stbyte.halfbyte.tclass1=val>>4; + header2ndbyte.halfbyte.tclass2=val; + + /* Write the bytes back to the header */ + h.ip6_start[0]=header1stbyte.fullbyte; + h.ip6_start[1]=header2ndbyte.fullbyte; + + return OP_SUCCESS; +} /* End of setTrafficClass() */ + + +u8 IPv6Header::getTrafficClass() const { + union{ + struct firstbyte{ + #if WORDS_BIGENDIAN + u8 ver:4; + u8 tclass1:4; + #else + u8 tclass1:4; + u8 ver:4; + #endif + }halfbyte; + u8 fullbyte; + }header1stbyte; + union{ + struct firstbyte{ + #if WORDS_BIGENDIAN + u8 tclass2:4; + u8 flow:4; + #else + u8 flow:4; + u8 tclass2:4; + #endif + }halfbyte; + u8 fullbyte; + }header2ndbyte; + union{ + struct firstbyte{ + #if WORDS_BIGENDIAN + u8 tclass1:4; + u8 tclass2:4; + #else + u8 tclass2:4; + u8 tclass1:4; + #endif + }halfbyte; + u8 fullbyte; + }finalbyte; + + header1stbyte.fullbyte = h.ip6_start[0]; + header2ndbyte.fullbyte = h.ip6_start[1]; + finalbyte.halfbyte.tclass1=header1stbyte.halfbyte.tclass1; + finalbyte.halfbyte.tclass2=header2ndbyte.halfbyte.tclass2; + return finalbyte.fullbyte; +} /* End of getTrafficClass() */ + + +int IPv6Header::setFlowLabel(u32 val){ + u32 netbyte = htonl(val); + u8 *pnt=(u8*)&netbyte; + union{ + struct firstbyte{ + #if WORDS_BIGENDIAN + u8 tclass2:4; + u8 flow:4; + #else + u8 flow:4; + u8 tclass2:4; + #endif + }halfbyte; + u8 fullbyte; + }header2ndbyte; + + header2ndbyte.fullbyte = h.ip6_start[1]; + header2ndbyte.halfbyte.flow=pnt[1]; + h.ip6_start[1]=header2ndbyte.fullbyte; + h.ip6_start[2]=pnt[2]; + h.ip6_start[3]=pnt[3]; + return OP_SUCCESS; +} /* End of setFlowLabel() */ + + +u32 IPv6Header::getFlowLabel() const { + u32 hostbyte=0; + u8 *pnt=(u8*)&hostbyte; + union{ + struct firstbyte{ + #if WORDS_BIGENDIAN + u8 tclass2:4; + u8 flow:4; + #else + u8 flow:4; + u8 tclass2:4; + #endif + }halfbyte; + u8 fullbyte; + }header2ndbyte; + + header2ndbyte.fullbyte = h.ip6_start[1]; + pnt[0]=0; + pnt[1]=header2ndbyte.halfbyte.flow; + pnt[2]=h.ip6_start[2]; + pnt[3]=h.ip6_start[3]; + hostbyte=ntohl(hostbyte); + return hostbyte; +} /* End of getFlowLabel() */ + + +int IPv6Header::setPayloadLength(u16 val){ + this->h.ip6_len = htons(val); + return OP_SUCCESS; +} /* End of setPayloadLength() */ + + +int IPv6Header::setPayloadLength(){ + int otherslen=0; + if (next!=NULL) + otherslen=next->getLen(); + setPayloadLength( otherslen ); + return OP_SUCCESS; +} /* End of setTotalLength() */ + + +u16 IPv6Header::getPayloadLength() const { + return ntohs(this->h.ip6_len); +} /* End of getPayloadLength() */ + + +int IPv6Header::setNextHeader(u8 val){ + this->h.ip6_nh = val; + return OP_SUCCESS; +} /* End of setNextHeader() */ + + +u8 IPv6Header::getNextHeader() const { + return this->h.ip6_nh; +} /* End of getNextHeader() */ + + +/** Sets field "next header" to the number that corresponds to the supplied + * protocol name. Currently only TCP, UDP and ICMP are supported. Any + * help to extend this functionality would be appreciated. For a list of all + * proto names and numbers check: + * http://www.iana.org/assignments/protocol-numbers/ */ +int IPv6Header::setNextHeader(const char *p){ + + if (p==NULL){ + printf("setNextProto(): NULL pointer supplied\n"); + return OP_FAILURE; + } + if( !strcasecmp(p, "TCP") ) + setNextHeader(6); /* 6=IANA number for proto TCP */ + else if( !strcasecmp(p, "UDP") ) + setNextHeader(17); /* 17=IANA number for proto UDP */ + else if( !strcasecmp(p, "ICMPv6")) + setNextHeader(58); /* 58=IANA number for proto ICMPv6 */ + else + netutil_fatal("setNextProto(): Invalid protocol number\n"); + return OP_SUCCESS; +} /* End of setNextHeader() */ + + +int IPv6Header::setHopLimit(u8 val){ + this->h.ip6_hopl = val; + return OP_SUCCESS; +} /* End of setHopLimit() */ + + +u8 IPv6Header::getHopLimit() const { + return this->h.ip6_hopl; +} /* End of getHopLimit() */ + + +int IPv6Header::setSourceAddress(u8 *val){ + if(val==NULL) + netutil_fatal("setSourceAddress(): NULL value supplied."); + memcpy(this->h.ip6_src, val, 16); + return OP_SUCCESS; +} /* End of setSourceAddress() */ + + +int IPv6Header::setSourceAddress(struct in6_addr val){ + memcpy(this->h.ip6_src, val.s6_addr, 16); + return OP_SUCCESS; +} /* End of setSourceAddress() */ + + +const u8 *IPv6Header::getSourceAddress() const { + return this->h.ip6_src; +} /* End of getSourceAddress() */ + + +/** Returns source IPv6 address + * @warning Returned value is in NETWORK byte order. */ +struct in6_addr IPv6Header::getSourceAddress(struct in6_addr *result) const { + struct in6_addr myaddr; + memset(&myaddr, 0, sizeof(myaddr)); + memcpy(myaddr.s6_addr, this->h.ip6_src, 16); + + if(result!=NULL) + *result=myaddr; + return myaddr; +} /* End of getSourceAddress() */ + + +int IPv6Header::setDestinationAddress(u8 *val){ + if(val==NULL) + netutil_fatal("setDestinationAddress(): NULL value supplied."); + memcpy(this->h.ip6_dst, val, 16); + return OP_SUCCESS; +} /* End of setDestinationAddress() */ + + +int IPv6Header::setDestinationAddress(struct in6_addr val){ + memcpy(this->h.ip6_dst, val.s6_addr, 16); + return OP_SUCCESS; +} /* End of setDestinationAddress() */ + + +/** Returns destination IPv6 address. */ +const u8 *IPv6Header::getDestinationAddress() const { + return this->h.ip6_dst; +} /* End of getDestinationAddress() */ + + +/** Returns destination IPv6 address + * @warning Returned value is in NETWORK byte order. */ +struct in6_addr IPv6Header::getDestinationAddress(struct in6_addr *result) const { + struct in6_addr myaddr; + memset(&myaddr, 0, sizeof(myaddr)); + memcpy(myaddr.s6_addr, this->h.ip6_dst, 16); + + if(result!=NULL) + *result=myaddr; + return myaddr; +} /* End of getDestinationAddress() */ + + +/** Returns the length of an IPv4 address. */ +u16 IPv6Header::getAddressLength() const { + return 16; +} /* End of getAddressLength()*/ + |