nmap/osscan.h

/***************************************************************************
 * osscan.h -- Routines used for OS detection via TCP/IP fingerprinting.   *
 * For more information on how this works in Nmap, see my paper at         *
 * https://nmap.org/osdetect/                                               *
 *                                                                         *
 ***********************IMPORTANT NMAP LICENSE TERMS************************
 *                                                                         *
 * The Nmap Security Scanner is (C) 1996-2019 Insecure.Com LLC ("The Nmap  *
 * Project"). Nmap is also a registered trademark of the Nmap Project.     *
 * 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 ("GPL"), BUT ONLY WITH ALL OF THE   *
 * CLARIFICATIONS AND EXCEPTIONS DESCRIBED HEREIN.  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@nmap.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 "derivative 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 with any software or content covered by this license          *
 * ("Covered Software"):                                                   *
 *                                                                         *
 * o Integrates source code from Covered Software.                         *
 *                                                                         *
 * o Reads or includes copyrighted data files, such as Nmap's nmap-os-db   *
 * or nmap-service-probes.                                                 *
 *                                                                         *
 * o Is designed specifically to execute Covered Software and parse the    *
 * results (as opposed to typical shell or execution-menu apps, which will *
 * execute anything you tell them to).                                     *
 *                                                                         *
 * o Includes Covered Software in a proprietary executable installer.  The *
 * installers produced by InstallShield are an example of this.  Including *
 * Nmap with other software in compressed or archival form does not        *
 * trigger this provision, provided appropriate open source decompression  *
 * or de-archiving software is widely available for no charge.  For the    *
 * purposes of this license, an installer is considered to include Covered *
 * Software even if it actually retrieves a copy of Covered Software from  *
 * another source during runtime (such as by downloading it from the       *
 * Internet).                                                              *
 *                                                                         *
 * o Links (statically or dynamically) to a library which does any of the  *
 * above.                                                                  *
 *                                                                         *
 * o Executes a helper program, module, or script to do any of the above.  *
 *                                                                         *
 * This list is not exclusive, but is meant to clarify our interpretation  *
 * of derived works with some common examples.  Other people may interpret *
 * the plain GPL differently, so we consider this a special exception to   *
 * the GPL that we apply to Covered Software.  Works which meet any of     *
 * these conditions must conform to all of the terms of this license,      *
 * particularly including the GPL Section 3 requirements of providing      *
 * source code and allowing free redistribution of the work as a whole.    *
 *                                                                         *
 * As another special exception to the GPL terms, the Nmap Project 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.                                  *
 *                                                                         *
 * The Nmap Project has permission to redistribute Npcap, a packet         *
 * capturing driver and library for the Microsoft Windows platform.        *
 * Npcap is a separate work with it's own license rather than this Nmap    *
 * license.  Since the Npcap license does not permit redistribution        *
 * without special permission, our Nmap Windows binary packages which      *
 * contain Npcap may not be redistributed without special permission.      *
 *                                                                         *
 * Any redistribution of Covered Software, including any derived works,    *
 * must obey and carry forward all of the terms of this license, including *
 * obeying all GPL rules and restrictions.  For example, source code of    *
 * the whole work must be provided and free redistribution must be         *
 * allowed.  All GPL references to "this License", are to be treated as    *
 * including the terms and conditions of this license text as well.        *
 *                                                                         *
 * Because this license imposes special exceptions to the GPL, Covered     *
 * Work may not be combined (even as part of a larger work) with plain GPL *
 * software.  The terms, conditions, and exceptions of this license must   *
 * be included as well.  This license is incompatible with some other open *
 * source licenses as well.  In some cases we can relicense portions of    *
 * Nmap or grant special permissions to use it in other open source        *
 * software.  Please contact fyodor@nmap.org with any such requests.       *
 * Similarly, we don't incorporate incompatible open source software into  *
 * Covered Software without special permission from the copyright holders. *
 *                                                                         *
 * If you have any questions about the licensing restrictions on using     *
 * Nmap in other works, we are happy to help.  As mentioned above, we also *
 * offer an 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 support and updates.  They also fund the continued         *
 * development of Nmap.  Please email sales@nmap.com for further           *
 * information.                                                            *
 *                                                                         *
 * If you have received a written license agreement or contract for        *
 * Covered Software stating terms other than these, you may choose to use  *
 * and redistribute Covered Software under those terms instead of these.   *
 *                                                                         *
 * 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 send your changes   *
 * to the dev@nmap.org mailing list 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 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 Nmap      *
 * license file for more details (it's in a COPYING file included with     *
 * Nmap, and also available from https://svn.nmap.org/nmap/COPYING)        *
 *                                                                         *
 ***************************************************************************/

/* $Id$ */

#ifndef OSSCAN_H
#define OSSCAN_H

#include <nbase.h>
#include <vector>

class Target;
class FingerPrintResultsIPv4;

#define OSSCAN_SUCCESS 0
#define OSSCAN_NOMATCHES -1
#define OSSCAN_TOOMANYMATCHES -2

/* We won't even consider matches with a lower accuracy than this */
#define OSSCAN_GUESS_THRESHOLD 0.85

/* The method used to calculate the Target::distance, included in OS
   fingerprints. */
enum dist_calc_method {
        DIST_METHOD_NONE,
        DIST_METHOD_LOCALHOST,
        DIST_METHOD_DIRECT,
        DIST_METHOD_ICMP,
        DIST_METHOD_TRACEROUTE
};

/**********************  STRUCTURES  ***********************************/

struct AVal {
  const char *attribute;
  const char *value;

  bool operator<(const AVal& other) const {
    return strcmp(attribute, other.attribute) < 0;
  }
};

struct OS_Classification {
  const char *OS_Vendor;
  const char *OS_Family;
  const char *OS_Generation; /* Can be NULL if unclassified */
  const char *Device_Type;
  std::vector<const char *> cpe;
};

/* A description of an operating system: a human-readable name and a list of
   classifications. */
struct FingerMatch {
  int line; /* For reference prints, the line # in nmap-os-db */
  /* For IPv6 matches, the number of fingerprints that contributed to this
   * classification group */
  unsigned short numprints;
  char *OS_name;
  std::vector<OS_Classification> OS_class;

  FingerMatch() {
    line = -1;
    OS_name = NULL;
  }
};

struct FingerTest {
  const char *name;
  std::vector<struct AVal> results;
  bool operator<(const FingerTest& other) const {
    return strcmp(name, other.name) < 0;
  }
};

struct FingerPrint {
  FingerMatch match;
  std::vector<FingerTest> tests;
  FingerPrint();
  void sort();
};
/* This structure contains the important data from the fingerprint
   database (nmap-os-db) */
struct FingerPrintDB {
  FingerPrint *MatchPoints;
  std::vector<FingerPrint *> prints;

  FingerPrintDB();
  ~FingerPrintDB();
};

/**********************  PROTOTYPES  ***********************************/

const char *fp2ascii(FingerPrint *FP);

/* Parses a single fingerprint from the memory region given.  If a
 non-null fingerprint is returned, the user is in charge of freeing it
 when done.  This function does not require the fingerprint to be 100%
 complete since it is used by scripts such as scripts/fingerwatch for
 which some partial fingerpritns are OK. */
FingerPrint *parse_single_fingerprint(char *fprint_orig);

/* These functions take a file/db name and open+parse it, returning an
   (allocated) FingerPrintDB containing the results.  They exit with
   an error message in the case of error. */
FingerPrintDB *parse_fingerprint_file(const char *fname);
FingerPrintDB *parse_fingerprint_reference_file(const char *dbname);

void free_fingerprint_file(FingerPrintDB *DB);

/* Compares 2 fingerprints -- a referenceFP (can have expression
   attributes) with an observed fingerprint (no expressions).  If
   verbose is nonzero, differences will be printed.  The comparison
   accuracy (between 0 and 1) is returned).  If MatchPoints is not NULL, it is
   a special "fingerprints" which tells how many points each test is worth. */
double compare_fingerprints(const FingerPrint *referenceFP, const FingerPrint *observedFP,
                            const FingerPrint *MatchPoints, int verbose);

/* Takes a fingerprint and looks for matches inside the passed in
   reference fingerprint DB.  The results are stored in in FPR (which
   must point to an instantiated FingerPrintResultsIPv4 class) -- results
   will be reverse-sorted by accuracy.  No results below
   accuracy_threshold will be included.  The max matches returned is
   the maximum that fits in a FingerPrintResultsIPv4 class.  */
void match_fingerprint(const FingerPrint *FP, FingerPrintResultsIPv4 *FPR,
                       const FingerPrintDB *DB, double accuracy_threshold);

/* Returns true if perfect match -- if num_subtests & num_subtests_succeeded are non_null it updates them.  if shortcircuit is zero, it does all the tests, otherwise it returns when the first one fails */

void freeFingerPrint(FingerPrint *FP);
void WriteSInfo(char *ostr, int ostrlen, bool isGoodFP,
                                const char *engine_id,
                                const struct sockaddr_storage *addr, int distance,
                                enum dist_calc_method distance_calculation_method,
                                const u8 *mac, int openTcpPort,
                                int closedTcpPort, int closedUdpPort);
const char *mergeFPs(FingerPrint *FPs[], int numFPs, bool isGoodFP,
                           const struct sockaddr_storage *addr, int distance,
                           enum dist_calc_method distance_calculation_method,
                           const u8 *mac, int openTcpPort, int closedTcpPort,
                           int closedUdpPort, bool wrapit);

#endif /*OSSCAN_H*/