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diff --git a/libnetutil/IPv4Header.cc b/libnetutil/IPv4Header.cc
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+/***************************************************************************
+ * IPv4Header.cc -- The IPv4Header 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 "IPv4Header.h"
+#include <assert.h>
+
+/******************************************************************************/
+/* CONTRUCTORS, DESTRUCTORS AND INITIALIZATION METHODS */
+/******************************************************************************/
+IPv4Header::IPv4Header() {
+ this->reset();
+} /* End of IPv4Header constructor */
+
+
+IPv4Header::~IPv4Header() {
+
+} /* End of IPv4Header destructor */
+
+
+/** Sets every attribute to its default value */
+void IPv4Header::reset() {
+ memset(&this->h, 0, sizeof(nping_ipv4_hdr_t));
+ this->ipoptlen=0;
+ this->length=20; /* Initial value 20. This will be incremented if options are used */
+ this->setVersion();
+ this->setHeaderLength();
+ this->setTOS(IPv4_DEFAULT_TOS);
+ this->setIdentification(IPv4_DEFAULT_ID);
+ this->setTTL(IPv4_DEFAULT_TTL);
+ this->setNextProto(IPv4_DEFAULT_PROTO);
+ this->setTotalLength();
+} /* End of IPv4Header destructor */
+
+
+/******************************************************************************/
+/* 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 *IPv4Header::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 IPv4Header class is able to hold a maximum of 60 bytes. If the
+ * supplied buffer is longer than that, only the first 60 bytes will be stored
+ * in the internal buffer.
+ * @warning Supplied len MUST be at least 20 bytes (min IP header length).
+ * @return OP_SUCCESS on success and OP_FAILURE in case of error */
+int IPv4Header::storeRecvData(const u8 *buf, size_t len){
+ if(buf==NULL || len<IP_HEADER_LEN){
+ return OP_FAILURE;
+ }else{
+ int stored_len = MIN((IP_HEADER_LEN + MAX_IP_OPTIONS_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 IPv4Header::protocol_id() const {
+ return HEADER_TYPE_IPv4;
+} /* End of protocol_id() */
+
+
+/** Performs some VERY BASIC checks that intend to validate the information
+ * stored in the internal buffer, as a valid protocol header.
+ * @warning If the information stored in the object has been set through a
+ * call to storeRecvData(), the object's internal length count may be updated
+ * if the validation is successful.
+ * @return the length, in bytes, of the header, if its found to be valid or
+ * OP_FAILURE (-1) otherwise. */
+int IPv4Header::validate(){
+ if(this->getVersion()!=4)
+ return OP_FAILURE;
+ else if( this->getHeaderLength()<5)
+ return OP_FAILURE;
+ else if( this->getHeaderLength()*4 > this->length)
+ return OP_FAILURE;
+ this->length=this->getHeaderLength()*4;
+ 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 IPv4Header::print(FILE *output, int detail) const {
+ static char ipstring[256];
+ memset(ipstring, 0, 256);
+ struct in_addr addr;
+ int frag_off = 8 * this->getFragOffset() & 8191; /* 2^13 - 1 */;
+ char ipinfo[512] = ""; /* Temp info about IP. */
+ char fragnfo[64] = ""; /* Temp info about fragmentation. */
+
+ fprintf(output, "IPv4[");
+
+ this->getSourceAddress(&addr);
+ inet_ntop(AF_INET, &addr, ipstring, sizeof(ipstring));
+ fprintf(output, "%s", ipstring);
+
+ fprintf(output, " >");
+
+ this->getDestinationAddress(&addr);
+ inet_ntop(AF_INET, &addr, ipstring, sizeof(ipstring));
+ fprintf(output, " %s", ipstring);
+
+ /* Is this a fragmented packet? is it the last fragment? */
+ if (frag_off || this->getMF()) {
+ Snprintf(fragnfo, sizeof(fragnfo), " frag offset=%d%s", frag_off, this->getMF() ? "+" : "");
+ }
+
+ /* Create a string with information relevant to the specified level of detail */
+ if( detail == PRINT_DETAIL_LOW ){
+ Snprintf(ipinfo, sizeof(ipinfo), "ttl=%d id=%d iplen=%d%s%s%s%s",
+ this->getTTL(), this->getIdentification(), this->getTotalLength(), fragnfo,
+ this->getHeaderLength()==5?"":" ipopts={",
+ this->getHeaderLength()?"":format_ip_options(this->h.options , MIN(this->getHeaderLength()*4, this->length-IP_HEADER_LEN)),
+ this->getHeaderLength()?"":"}");
+ }else if( detail == PRINT_DETAIL_MED ){
+ Snprintf(ipinfo, sizeof(ipinfo), "ttl=%d id=%d proto=%d csum=0x%04X iplen=%d%s%s%s%s",
+ this->getTTL(), this->getIdentification(),
+ this->getNextProto(), this->getSum(),
+ this->getTotalLength(), fragnfo,
+ this->getHeaderLength()==5?"":" ipopts={",
+ this->getHeaderLength()==5?"":format_ip_options(this->h.options , MIN(this->getHeaderLength()*4, this->length-IP_HEADER_LEN)),
+ this->getHeaderLength()==5?"":"}");
+ }else if( detail>=PRINT_DETAIL_HIGH ){
+ Snprintf(ipinfo, sizeof(ipinfo), "ver=%d ihl=%d tos=0x%02x iplen=%d id=%d%s%s%s%s foff=%d%s ttl=%d proto=%d csum=0x%04X%s%s%s",
+ this->getVersion(), this->getHeaderLength(),
+ this->getTOS(), this->getTotalLength(),
+ this->getIdentification(),
+ (this->getRF() ||this->getDF()||this->getMF()) ? " flg=" : "",
+ (this->getRF()) ? "x" : "",
+ (this->getDF() )? "D" : "",
+ (this->getMF() )? "M": "",
+ frag_off, (this->getMF()) ? "+" : "",
+ this->getTTL(), this->getNextProto(),
+ this->getSum(),
+ this->getHeaderLength()==5?"":" ipopts={",
+ this->getHeaderLength()==5?"":format_ip_options(this->h.options , MIN(this->getHeaderLength()*4, this->length-IP_HEADER_LEN)),
+ this->getHeaderLength()==5?"":"}");
+ }
+
+ 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 */
+/******************************************************************************/
+
+int IPv4Header::setVersion(){
+ h.ip_v = 4;
+ return 4;
+} /* End of setVersion() */
+
+
+u8 IPv4Header::getVersion() const {
+ return (u8)h.ip_v;
+} /* End of getVersion() */
+
+
+int IPv4Header::setHeaderLength(){
+ h.ip_hl = 5 + (ipoptlen/4);
+ return OP_SUCCESS;
+} /* End of setHeaderLength() */
+
+
+int IPv4Header::setHeaderLength(u8 l){
+ h.ip_hl = l;
+ return OP_SUCCESS;
+} /* End of setHeaderLength() */
+
+
+u8 IPv4Header::getHeaderLength() const {
+ return h.ip_hl;
+} /* End of getHeaderLength() */
+
+
+int IPv4Header::setTOS(u8 v){
+ h.ip_tos = v;
+ return OP_SUCCESS;
+} /* End of setTOS() */
+
+
+u8 IPv4Header::getTOS() const {
+ return h.ip_tos;
+} /* End of getTOS() */
+
+
+int IPv4Header::setTotalLength(){
+ int mylen = 4*getHeaderLength();
+ int otherslen=0;
+
+ if (next!=NULL)
+ otherslen=next->getLen();
+ h.ip_len=htons( mylen+otherslen );
+ return OP_SUCCESS;
+} /* End of setTotalLength() */
+
+
+/** @warning Supplied value MUST be in host byte order because it will get
+ * converted by this method using htons() */
+int IPv4Header::setTotalLength(u16 l){
+ h.ip_len = htons(l);
+ return OP_SUCCESS;
+} /* End of setTotalLength() */
+
+
+/** @warning Returned value is already in host byte order. */
+u16 IPv4Header::getTotalLength() const {
+ return ntohs(h.ip_len);
+} /* End of getTotalLength() */
+
+
+/** Sets identification field to a random value */
+int IPv4Header::setIdentification(){
+ h.ip_id=get_random_u16();
+ return OP_SUCCESS;
+} /* End of setIdentification() */
+
+
+/** @warning Supplied value MUST be in host byte order because it will get
+ * converted by this method using htons() */
+int IPv4Header::setIdentification(u16 i){
+ h.ip_id = htons(i);
+ return OP_SUCCESS;
+} /* End of setIdentification() */
+
+
+/** @warning Returned value is already in host byte order. */
+u16 IPv4Header::getIdentification() const {
+ return ntohs(h.ip_id);
+} /* End of getIdentification() */
+
+
+/** Sets fragment offset field to a random value */
+int IPv4Header::setFragOffset(){
+ /* TODO: Should we check here that i<8192 ? */
+ h.ip_off=get_random_u16();
+ return OP_SUCCESS;
+} /* End of setFragOffset() */
+
+
+/** @warning Supplied value MUST be in host byte order because it will get
+ * converted by this method using htons() */
+int IPv4Header::setFragOffset(u16 i){
+ /* TODO: Should we check here that i<8192 ? */
+ h.ip_off = htons(i);
+ return OP_SUCCESS;
+} /* End of setFragOffset() */
+
+
+/** @warning Returned value is already in host byte order. */
+u16 IPv4Header::getFragOffset() const {
+ return ntohs(h.ip_off);
+} /* End of getFragOffset() */
+
+
+/** Set RF flag */
+int IPv4Header::setRF(){
+ h.ip_off |= htons(IP_RF);
+ return OP_SUCCESS;
+} /* End of setRF() */
+
+/** Unset RF flag */
+int IPv4Header::unsetRF(){
+ h.ip_off = h.ip_off & ~(htons(IP_RF));
+ return OP_SUCCESS;
+} /* End of unsetRF() */
+
+
+/** Get RF flag */
+bool IPv4Header::getRF() const {
+ return h.ip_off & htons(IP_RF);
+} /* End of getRF() */
+
+
+/** Set MF flag */
+int IPv4Header::setMF(){
+ h.ip_off |= htons(IP_MF);
+ return OP_SUCCESS;
+} /* End of setMF() */
+
+
+/** Unset MF flag */
+int IPv4Header::unsetMF(){
+ h.ip_off = h.ip_off & ~(htons(IP_MF));
+ return OP_SUCCESS;
+} /* End of unsetMF() */
+
+
+/* Get MF flag */
+bool IPv4Header::getMF() const {
+ return h.ip_off & htons(IP_MF);
+} /* End of getMF() */
+
+
+/** Set DF flag */
+int IPv4Header::setDF(){
+ h.ip_off |= htons(IP_DF);
+ return OP_SUCCESS;
+} /* End of setDF() */
+
+
+/** Unset DF flag */
+int IPv4Header::unsetDF(){
+ h.ip_off = h.ip_off & ~(htons(IP_DF));
+ return OP_SUCCESS;
+} /* End of unsetDF() */
+
+
+/** Get DF flag */
+bool IPv4Header::getDF() const {
+ return h.ip_off & htons(IP_DF);
+} /* End of getDF) */
+
+
+/** Sets TTL field to a random value */
+int IPv4Header::setTTL(){
+ h.ip_ttl=get_random_u8();
+ return OP_SUCCESS;
+} /* End of setTTL() */
+
+
+/** @warning Supplied value MUST be in host byte order because it will get
+ * converted by this method using htons() */
+int IPv4Header::setTTL(u8 t){
+ h.ip_ttl = t;
+ return OP_SUCCESS;
+} /* End of setTTL() */
+
+
+/** @warning Returned value is already in host byte order. */
+u8 IPv4Header::getTTL() const {
+ return h.ip_ttl;
+} /* End of getTTL() */
+
+
+/** Sets field "next protocol" to the supplied value.
+ * @warning: No error checks are made. Make sure the supplied value
+ * corresponds to an actual IANA number. Check
+ * http://www.iana.org/assignments/protocol-numbers/ for more details. */
+int IPv4Header::setNextProto(u8 p){
+ h.ip_p = p;
+ return OP_SUCCESS;
+} /* End of setNextProto() */
+
+
+/** Sets field "next protocol" 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 IPv4Header::setNextProto(const char *p){
+ if (p==NULL){
+ printf("setNextProto(): NULL pointer supplied\n");
+ return OP_FAILURE;
+ }
+ if( !strcasecmp(p, "TCP") )
+ h.ip_p=6; /* 6=IANA number for proto TCP */
+
+ else if( !strcasecmp(p, "UDP") )
+ h.ip_p=17; /* 17=IANA number for proto UDP */
+
+ else if( !strcasecmp(p, "ICMP") )
+ h.ip_p=1; /* 1=IANA number for proto ICMP */
+ else{
+ printf("setNextProto(): Invalid protocol number\n");
+ return OP_FAILURE;
+ }
+ return OP_SUCCESS;
+} /* End of setNextProto() */
+
+
+/** Returns next protocol number */
+u8 IPv4Header::getNextProto() const {
+ return h.ip_p;
+} /* End of getNextProto() */
+
+
+u8 IPv4Header::getNextHeader() const {
+ return this->getNextProto();
+} /* End of getNextHeader() */
+
+
+int IPv4Header::setNextHeader(u8 val){
+ return this->setNextProto(val);
+} /* End of setNextHeader() */
+
+
+/** Computes the IPv4 header checksum and sets the ip_sum field to the right
+ * value. */
+int IPv4Header::setSum(){
+ h.ip_sum = 0;
+ /* ip_checksum() comes from libdnet */
+ ip_checksum((void*)&h, 20 + ipoptlen );
+ return OP_SUCCESS;
+} /* End of setSum() */
+
+
+/** @warning Sum is set to supplied value with NO byte ordering conversion
+ * performed.
+ * @warning If sum is supplied this way, no error checks are made. Caller is
+ * responsible for the correctness of the value. */
+int IPv4Header::setSum(u16 s){
+ h.ip_sum = s;
+ return OP_SUCCESS;
+} /* End of setSum() */
+
+
+/** Set the checksum field to a random value */
+int IPv4Header::setSumRandom(){
+ h.ip_sum=get_random_u16();
+ return OP_SUCCESS;
+} /* End of setRandomSum() */
+
+
+/** Returns the value of the checksum field.
+ * @warning The returned value is in NETWORK byte order, no conversion is
+ * performed */
+u16 IPv4Header::getSum() const {
+ return h.ip_sum;
+} /* End of getSum() */
+
+
+/** Sets destination IP address.
+ * @warning Destination IP must be supplied in NETWORK byte order. Usually
+ * all regular library functions return IPs in network byte order so there
+ * should be no need to worry. */
+int IPv4Header::setDestinationAddress(u32 d){
+ h.ip_dst.s_addr = d;
+ return OP_SUCCESS;
+} /* End of setDestinationAddress() */
+
+/** Sets destination IP address.
+ * @warning Destination IP must be supplied in NETWORK byte order. Usually
+ * all regular library functions return IPs in network byte order so there
+ * should be no need to worry. */
+int IPv4Header::setDestinationAddress(struct in_addr d){
+ h.ip_dst=d;
+ return OP_SUCCESS;
+} /* End of setDestinationAddress() */
+
+
+/** Returns destination IP address.
+ * @warning Returned value is in NETWORK byte order. */
+const u8 *IPv4Header::getDestinationAddress() const {
+ return (u8 *)(&h.ip_dst.s_addr);
+} /* End of getDestinationAddress() */
+
+
+/** Returns destination IP address.
+ * @warning Returned value is in NETWORK byte order. */
+struct in_addr IPv4Header::getDestinationAddress(struct in_addr *result) const {
+ if(result!=NULL)
+ *result=this->h.ip_dst;
+ return h.ip_dst;
+} /* End of getDestinationAddress() */
+
+
+/** Sets source IP address.
+ * @warning Destination IP must be supplied in NETWORK byte order. Usually
+ * all regular library functions return IPs in network byte order so there
+ * should be no need to worry. */
+int IPv4Header::setSourceAddress(u32 d){
+ h.ip_src.s_addr = d;
+ return OP_SUCCESS;
+} /* End of setSourceAddress() */
+
+
+/** Sets source IP address.
+ * @warning Destination IP must be supplied in NETWORK byte order. Usually
+ * all regular library functions return IPs in network byte order so there
+ * should be no need to worry. */
+int IPv4Header::setSourceAddress(struct in_addr d){
+ h.ip_src=d;
+ return OP_SUCCESS;
+} /* End of setSourceAddress() */
+
+
+/** Returns source ip
+ * @warning Returned value is in NETWORK byte order. */
+const u8 *IPv4Header::getSourceAddress() const {
+ return (u8 *)(&h.ip_src.s_addr);
+} /* End of getSourceAddress() */
+
+
+/** Returns source ip
+ * @warning Returned value is in NETWORK byte order. */
+struct in_addr IPv4Header::getSourceAddress(struct in_addr *result) const {
+ if(result!=NULL)
+ *result=this->h.ip_src;
+ return h.ip_src;
+} /* End of getSourceAddress() */
+
+
+/** Returns the length of an IPv4 address. */
+u16 IPv4Header::getAddressLength() const {
+ return 4;
+} /* End of getAddressLength()*/
+
+
+int IPv4Header::setOpts(const char *txt){
+ int foo=0;
+ int bar=0;
+ int ret=0;
+ u8 buffer[128];
+ char errstr[256];
+
+ if(txt==NULL){
+ printf("setOpts(): NULL pointer supplied.\n");
+ return OP_FAILURE;
+ }
+
+ /* Parse IP options */
+ if((ret=parse_ip_options(txt, buffer, 128, &foo, &bar, errstr, sizeof(errstr)))==OP_FAILURE){
+ printf("%s\n", errstr);
+ return OP_FAILURE;
+ }else{
+ /* Copy options to our IP header */
+ this->setOpts(buffer, ret);
+ }
+ return OP_SUCCESS;
+} /* End of setOpts() */
+
+
+int IPv4Header::setOpts(u8 *opts_buff, u32 opts_len){
+ if(opts_buff==NULL || opts_len==0)
+ return OP_FAILURE;
+ assert(opts_len<=MAX_IP_OPTIONS_LEN); /* Max length for IP options */
+ memcpy(this->h.options, opts_buff, opts_len);
+ this->ipoptlen=opts_len;
+ this->length += opts_len;
+ this->setHeaderLength();
+ return OP_SUCCESS;
+} /* End of setOpts() */
+
+
+const u8 *IPv4Header::getOpts() const {
+ return h.options;
+} /* End of getOpts() */
+
+
+const u8 *IPv4Header::getOpts(int *len) const {
+ if(len==NULL)
+ printf("getOpts(): NULL pointer supplied.\n");
+ else
+ *len=ipoptlen;
+ return h.options;
+} /* End of getOpts() */
+
+
+int IPv4Header::printOptions() const {
+ char *p=format_ip_options(this->h.options, this->ipoptlen);
+ printf("%s", p);
+ return OP_SUCCESS;
+} /* End of printOptions() */
+
+const char *IPv4Header::getOptionsString() const {
+ return format_ip_options(this->h.options, this->ipoptlen);
+} /* End of getOptionsString() */