/*************************************************************************** * TCPHeader.h -- The TCPHeader Class represents a TCP packet. 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) 1996-2022 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. 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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 __TCPHEADER_H__ #define __TCPHEADER_H__ 1 #include "TransportLayerElement.h" /* TCP FLAGS */ #define TH_FIN 0x01 #define TH_SYN 0x02 #define TH_RST 0x04 #define TH_PSH 0x08 #define TH_ACK 0x10 #define TH_URG 0x20 #define TH_ECN 0x40 #define TH_CWR 0x80 /* TCP OPTIONS */ #define TCPOPT_EOL 0 /* End of Option List (RFC793) */ #define TCPOPT_NOOP 1 /* No-Operation (RFC793) */ #define TCPOPT_MSS 2 /* Maximum Segment Size (RFC793) */ #define TCPOPT_WSCALE 3 /* WSOPT - Window Scale (RFC1323) */ #define TCPOPT_SACKOK 4 /* SACK Permitted (RFC2018) */ #define TCPOPT_SACK 5 /* SACK (RFC2018) */ #define TCPOPT_ECHOREQ 6 /* Echo (obsolete) (RFC1072)(RFC6247) */ #define TCPOPT_ECHOREP 7 /* Echo Reply (obsolete) (RFC1072)(RFC6247) */ #define TCPOPT_TSTAMP 8 /* TSOPT - Time Stamp Option (RFC1323) */ #define TCPOPT_POCP 9 /* Partial Order Connection Permitted (obsol.) */ #define TCPOPT_POSP 10 /* Partial Order Service Profile (obsolete) */ #define TCPOPT_CC 11 /* CC (obsolete) (RFC1644)(RFC6247) */ #define TCPOPT_CCNEW 12 /* CC.NEW (obsolete) (RFC1644)(RFC6247) */ #define TCPOPT_CCECHO 13 /* CC.ECHO (obsolete) (RFC1644)(RFC6247) */ #define TCPOPT_ALTCSUMREQ 14 /* TCP Alternate Checksum Request (obsolete) */ #define TCPOPT_ALTCSUMDATA 15 /* TCP Alternate Checksum Data (obsolete) */ #define TCPOPT_MD5 19 /* MD5 Signature Option (obsolete) (RFC2385) */ #define TCPOPT_SCPS 20 /* SCPS Capabilities */ #define TCPOPT_SNACK 21 /* Selective Negative Acknowledgements */ #define TCPOPT_QSRES 27 /* Quick-Start Response (RFC4782) */ #define TCPOPT_UTO 28 /* User Timeout Option (RFC5482) */ #define TCPOPT_AO 29 /* TCP Authentication Option (RFC5925) */ /* Internal constants */ #define TCP_HEADER_LEN 20 #define MAX_TCP_OPTIONS_LEN 40 #define MAX_TCP_PAYLOAD_LEN 65495 /**< Max len of a TCP packet */ /* Default header values */ #define TCP_DEFAULT_SPORT 20 #define TCP_DEFAULT_DPORT 80 #define TCP_DEFAULT_SEQ 0 #define TCP_DEFAULT_ACK 0 #define TCP_DEFAULT_FLAGS 0x02 #define TCP_DEFAULT_WIN 8192 #define TCP_DEFAULT_URP 0 /* +--------+--------+---------+--------... | Type | Len | Value +--------+--------+---------+--------... */ struct nping_tcp_opt { u8 type; /* Option type code. */ u8 len; /* Option length. */ u8 *value; /* Option value */ }__attribute__((__packed__)); typedef struct nping_tcp_opt nping_tcp_opt_t; class TCPHeader : public TransportLayerElement { 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Source Port | Destination Port | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Sequence Number | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Acknowledgment Number | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Offset| Res. |C|E|U|A|P|R|S|F| Window | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Checksum | Urgent Pointer | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Options | Padding | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ */ struct nping_tcp_hdr { u16 th_sport; /* Source port */ u16 th_dport; /* Destination port */ u32 th_seq; /* Sequence number */ u32 th_ack; /* Acknowledgement number */ #if WORDS_BIGENDIAN u8 th_off:4; /* Data offset */ u8 th_x2:4; /* Reserved */ #else u8 th_x2:4; /* Reserved */ u8 th_off:4; /* Data offset */ #endif u8 th_flags; /* Flags */ u16 th_win; /* Window size */ u16 th_sum; /* Checksum */ u16 th_urp; /* Urgent pointer */ u8 options[MAX_TCP_OPTIONS_LEN ]; /* Space for TCP Options */ }__attribute__((__packed__)); typedef struct nping_tcp_hdr nping_tcp_hdr_t; nping_tcp_hdr_t h; int tcpoptlen; /**< Length of TCP options */ void __tcppacketoptinfo(const u8 *optp, int len, char *result, int bufsize) const; public: TCPHeader(); ~TCPHeader(); 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; int setSourcePort(u16 p); u16 getSourcePort() const; int setDestinationPort(u16 p); u16 getDestinationPort() const; int setSeq(u32 p); u32 getSeq() const; int setAck(u32 p); u32 getAck() const; int setOffset(u8 o); int setOffset(); u8 getOffset() const; int setReserved(u8 r); u8 getReserved() const; int setFlags(u8 f); u8 getFlags() const; u16 getFlags16() const; bool setCWR(); bool unsetCWR(); bool getCWR() const; bool setECE(); bool unsetECE(); bool getECE() const; bool setECN(); bool unsetECN(); bool getECN() const; bool setURG(); bool unsetURG(); bool getURG() const; bool setACK(); bool unsetACK(); bool getACK() const; bool setPSH(); bool unsetPSH(); bool getPSH() const; bool setRST(); bool unsetRST(); bool getRST() const; bool setSYN(); bool unsetSYN(); bool getSYN() const; bool setFIN(); bool unsetFIN(); bool getFIN() const; int setWindow(u16 p); u16 getWindow() const; int setUrgPointer(u16 l); u16 getUrgPointer() const; int setSum(u16 s); int setSum(struct in_addr source, struct in_addr destination); int setSum(); int setSumRandom(); int setSumRandom(struct in_addr source, struct in_addr destination); u16 getSum() const; int setOptions(const u8 *optsbuff, size_t optslen); const u8 *getOptions(size_t *optslen) const; nping_tcp_opt_t getOption(unsigned int index) const; static const char *optcode2str(u8 optcode); }; /* End of class TCPHeader */ #endif /* __TCPHEADER_H__ */