/*************************************************************************** * IPv4Header.h -- 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) 1996-2022 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. */ #ifndef IPV4HEADER_H #define IPV4HEADER_H 1 #include "NetworkLayerElement.h" #define IP_RF 0x8000 /* Reserved fragment flag */ #define IP_DF 0x4000 /* Don't fragment flag */ #define IP_MF 0x2000 /* More fragments flag */ #define IP_OFFMASK 0x1fff /* Mask for fragmenting bits */ #define IP_HEADER_LEN 20 /* Length of the standard header */ #define MAX_IP_OPTIONS_LEN 40 /* Max Length for IP Options */ /* Default header values */ #define IPv4_DEFAULT_TOS 0 #define IPv4_DEFAULT_ID 0 #define IPv4_DEFAULT_TTL 64 #define IPv4_DEFAULT_PROTO 6 /* TCP */ class IPv4Header : public NetworkLayerElement { private: /* 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |Version| IHL |Type of Service| Total Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Identification |Flags| Fragment Offset | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Time to Live | Protocol | Header Checksum | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Source Address | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Destination Address | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Options | Padding | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ */ struct nping_ipv4_hdr { #if WORDS_BIGENDIAN u8 ip_v:4; /* Version */ u8 ip_hl:4; /* Header length */ #else u8 ip_hl:4; /* Header length */ u8 ip_v:4; /* Version */ #endif u8 ip_tos; /* Type of service */ u16 ip_len; /* Total length */ u16 ip_id; /* Identification */ u16 ip_off; /* Fragment offset field */ u8 ip_ttl; /* Time to live */ u8 ip_p; /* Protocol */ u16 ip_sum; /* Checksum */ struct in_addr ip_src; /* Source IP address */ struct in_addr ip_dst; /* Destination IP address */ u8 options[MAX_IP_OPTIONS_LEN]; /* IP Options */ }__attribute__((__packed__)); typedef struct nping_ipv4_hdr nping_ipv4_hdr_t; nping_ipv4_hdr_t h; int ipoptlen; /**< Length of IP options */ public: /* Misc */ IPv4Header(); ~IPv4Header(); void reset(); u8 *getBufferPointer(); int storeRecvData(const u8 *buf, size_t len); int protocol_id() const; int validate(); int print(FILE *output, int detail) const; /* IP version */ int setVersion(); u8 getVersion() const; /* Header Length */ int setHeaderLength(); int setHeaderLength(u8 l); u8 getHeaderLength() const; /* Type of Service */ int setTOS(u8 v); u8 getTOS() const; /* Total length of the datagram */ int setTotalLength(); int setTotalLength(u16 l); u16 getTotalLength() const; /* Identification value */ int setIdentification(); int setIdentification(u16 i); u16 getIdentification() const; /* Fragment Offset */ int setFragOffset(); int setFragOffset(u16 f); u16 getFragOffset() const; /* Flags */ int setRF(); int unsetRF(); bool getRF() const; int setDF(); int unsetDF(); bool getDF() const; int setMF(); int unsetMF(); bool getMF() const; /* Time to live */ int setTTL(); int setTTL(u8 t); u8 getTTL() const; /* Next protocol */ int setNextProto(u8 p); int setNextProto(const char *p); u8 getNextProto() const; int setNextHeader(u8 val); u8 getNextHeader() const; /* Checksum */ int setSum(); int setSum(u16 s); int setSumRandom(); u16 getSum() const; /* Destination IP */ int setDestinationAddress(u32 d); int setDestinationAddress(struct in_addr d); const u8 *getDestinationAddress() const; struct in_addr getDestinationAddress(struct in_addr *result) const; /* Source IP */ int setSourceAddress(u32 d); int setSourceAddress(struct in_addr d); const u8 *getSourceAddress() const; struct in_addr getSourceAddress(struct in_addr *result) const; u16 getAddressLength() const; /* IP Options */ int setOpts(const char *txt); int setOpts(u8 *opts_buff, u32 opts_len); const u8 *getOpts() const; const u8 *getOpts(int *len) const; int printOptions() const; const char *getOptionsString() const; }; /* End of class IPv4Header */ #endif