/***************************************************************************
 * service_scan.h -- Routines used for service fingerprinting to determine *
 * what application-level protocol is listening on a given port            *
 * (e.g. snmp, http, ftp, smtp, etc.)                                      *
 *                                                                         *
 ***********************IMPORTANT NMAP LICENSE TERMS************************
 *                                                                         *
 * The Nmap Security Scanner is (C) 1996-2018 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 SERVICE_SCAN_H
#define SERVICE_SCAN_H

#include "portlist.h"
#include "scan_lists.h"

#include <vector>

#ifdef HAVE_CONFIG_H
/* Needed for HAVE_PCRE_PCRE_H below */
#include "nmap_config.h"
#endif /* HAVE_CONFIG_H */

#ifdef HAVE_PCRE_PCRE_H
# include <pcre/pcre.h>
#else
# include <pcre.h>
#endif

#undef NDEBUG
#include <assert.h>

/**********************  DEFINES/ENUMS ***********************************/
#define DEFAULT_SERVICEWAITMS 5000
#define DEFAULT_TCPWRAPPEDMS 2000   // connections closed after this timeout are not considered "tcpwrapped"
#define DEFAULT_CONNECT_TIMEOUT 5000
#define DEFAULT_CONNECT_SSL_TIMEOUT 8000  // includes connect() + ssl negotiation
#define SERVICEMATCH_REGEX 1
#define MAXFALLBACKS 20 /* How many comma separated fallbacks are allowed in the service-probes file? */

// #define SERVICEMATCH_STATIC 2 -- no longer supported

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

// This is returned when we find a match
struct MatchDetails {
// Rather the match is a "soft" service only match, where we should
// continue to look for a better match.
  bool isSoft;

  // The service that was matched (Or NULL) zero-terminated.
  const char *serviceName;

  // The line number of this match in nmap-service-probes.
  int lineno;

  // The product/version/info for the service that was matched (Or NULL)
  // zero-terminated.
  const char *product;
  const char *version;
  const char *info;

  // More information from a match. Zero-terminated strings or NULL.
  const char *hostname;
  const char *ostype;
  const char *devicetype;

  // CPE identifiers for application, OS, and hardware type.
  const char *cpe_a;
  const char *cpe_o;
  const char *cpe_h;
};

/**********************  CLASSES     ***********************************/

class ServiceProbeMatch {
 public:
  ServiceProbeMatch();
  ~ServiceProbeMatch();

// match text from the nmap-service-probes file.  This must be called
// before you try and do anything with this match.  This function
// should be passed the whole line starting with "match" or
// "softmatch" in nmap-service-probes.  The line number that the text
// is provided so that it can be reported in error messages.  This
// function will abort the program if there is a syntax problem.
  void InitMatch(const char *matchtext, int lineno);

  // If the buf (of length buflen) match the regex in this
  // ServiceProbeMatch, returns the details of the match (service
  // name, version number if applicable, and whether this is a "soft"
  // match.  If the buf doesn't match, the serviceName field in the
  // structure will be NULL.  The MatchDetails returned is only valid
  // until the next time this function is called.  The only exception
  // is that the serviceName field can be saved throughout program
  // execution.  If no version matched, that field will be NULL.
  const struct MatchDetails *testMatch(const u8 *buf, int buflen);
// Returns the service name this matches
  const char *getName() { return servicename; }
  // The Line number where this match string was defined.  Returns
  // -1 if unknown.
  int getLineNo() { return deflineno; }
 private:
  int deflineno; // The line number where this match is defined.
  bool isInitialized; // Has InitMatch yet been called?
  char *servicename;
  int matchtype; // SERVICEMATCH_REGEX or SERVICESCAN_STATIC
  char *matchstr; // Regular expression text, or static string
  int matchstrlen; // Because static strings may have embedded NULs
  pcre *regex_compiled;
  pcre_extra *regex_extra;
  bool matchops_ignorecase;
  bool matchops_dotall;
  bool isSoft; // is this a soft match? ("softmatch" keyword in nmap-service-probes)
  // If any of these 3 are non-NULL, a product, version, or template
  // string was given to deduce the application/version info via
  // substring matches.
  char *product_template;
  char *version_template;
  char *info_template;
  // More templates:
  char *hostname_template;
  char *ostype_template;
  char *devicetype_template;
  std::vector<char *> cpe_templates;
  // The anchor is for SERVICESCAN_STATIC matches.  If the anchor is not -1, the match must
  // start at that zero-indexed position in the response str.
  int matchops_anchor;
// Details to fill out and return for testMatch() calls
  struct MatchDetails MD_return;

  // Use the six version templates and the match data included here
  // to put the version info into the given strings, (as long as the sizes
  // are sufficient).  Returns zero for success.  If no template is available
  // for a string, that string will have zero length after the function
  // call (assuming the corresponding length passed in is at least 1)
  int getVersionStr(const u8 *subject, int subjectlen, int *ovector,
                  int nummatches, char *product, int productlen,
                  char *version, int versionlen, char *info, int infolen,
                  char *hostname, int hostnamelen, char *ostype, int ostypelen,
                  char *devicetype, int devicetypelen,
                  char *cpe_a, int cpe_alen,
                  char *cpe_h, int cpe_hlen,
                  char *cpe_o, int cpe_olen);
};


class ServiceProbe {
 public:
  ServiceProbe();
  ~ServiceProbe();
  const char *getName() { return probename; }
  // Returns true if this is the "null" probe, meaning it sends no probe and
  // only listens for a banner.  Only TCP services have this.
  bool isNullProbe() { return (probestringlen == 0); }
  bool isProbablePort(u16 portno); // Returns true if the portnumber given was listed
                                   // as a port that is commonly identified by this
                                   // probe (e.g. an SMTP probe would commonly identify port 25)
// Amount of time to wait after a connection succeeds (or packet sent) for a responses.
  int totalwaitms;
  // If the connection succeeds but closes before this time, it's tcpwrapped.
  int tcpwrappedms;

  // Parses the "probe " line in the nmap-service-probes file.  Pass the rest of the line
  // after "probe ".  The format better be:
  // [TCP|UDP] [probename] "probetext"
  // the lineno is requested because this function will bail with an error
  // (giving the line number) if it fails to parse the string.
  void setProbeDetails(char *pd, int lineno);

  // obtains the probe string (in raw binary form) and the length.  The string will be
  // NUL-terminated, but there may be other \0 in the string, so the termination is only
  // done for ease of printing ASCII probes in debugging cases.
  const u8 *getProbeString(int *stringlen) { *stringlen = probestringlen; return probestring; }
  void setProbeString(const u8 *ps, int stringlen);

  /* Protocols are IPPROTO_TCP and IPPROTO_UDP */
  u8 getProbeProtocol() {
    assert(probeprotocol == IPPROTO_TCP || probeprotocol == IPPROTO_UDP);
    return probeprotocol;
  }
  void setProbeProtocol(u8 protocol) { probeprotocol = protocol; }

  // Takes a string as given in the 'ports '/'sslports ' line of
  // nmap-service-probes.  Pass in the list from the appropriate
  // line.  For 'sslports', tunnel should be specified as
  // SERVICE_TUNNEL_SSL.  Otherwise use SERVICE_TUNNEL_NONE.  The line
  // number is requested because this function will bail with an error
  // (giving the line number) if it fails to parse the string.  Ports
  // are a comma separated list of ports and ranges
  // (e.g. 53,80,6000-6010).
  void setProbablePorts(enum service_tunnel_type tunnel,
                        const char *portstr, int lineno);

  /* Returns true if the passed in port is on the list of probable
     ports for this probe and tunnel type.  Use a tunnel of
     SERVICE_TUNNEL_SSL or SERVICE_TUNNEL_NONE as appropriate */
  bool portIsProbable(enum service_tunnel_type tunnel, u16 portno);
  // Returns true if the passed in service name is among those that can
  // be detected by the matches in this probe;
  bool serviceIsPossible(const char *sname);

  // Takes a string following a Rarity directive in the probes file.
  // The string should contain a single integer between 1 and 9. The
  // default rarity is 5. This function will bail if the string is invalid.
  void setRarity(const char *portstr, int lineno);

  // Simply returns the rarity of this probe
  int getRarity() const { return rarity; }

  // Takes a match line in a probe description and adds it to the
  // list of matches for this probe.  This function should be passed
  // the whole line starting with "match" or "softmatch" in
  // nmap-service-probes.  The line number is requested because this
  // function will bail with an error (giving the line number) if it
  // fails to parse the string.
  void addMatch(const char *match, int lineno);

  // If the buf (of length buflen) matches one of the regexes in this
  // ServiceProbe, returns the details of the nth match (service name,
  // version number if applicable, and whether this is a "soft" match.
  // If the buf doesn't match, the serviceName field in the structure
  // will be NULL.  The MatchDetails returned is only valid until the
  // next time this function is called.  The only exception is that the
  // serviceName field can be saved throughout program execution.  If
  // no version matched, that field will be NULL. This function may
  // return NULL if there are no match lines at all in this probe.
  const struct MatchDetails *testMatch(const u8 *buf, int buflen, int n);

  char *fallbackStr;
  ServiceProbe *fallbacks[MAXFALLBACKS+1];

 private:
  void setPortVector(std::vector<u16> *portv, const char *portstr,
                                 int lineno);
  char *probename;

  u8 *probestring;
  int probestringlen;
  std::vector<u16> probableports;
  std::vector<u16> probablesslports;
  int rarity;
  std::vector<const char *> detectedServices;
  int probeprotocol;
  std::vector<ServiceProbeMatch *> matches; // first-ever use of STL in Nmap!
};

class AllProbes {
public:
  AllProbes();
  ~AllProbes();
  // Tries to find the probe in this AllProbes class which have the
  // given name and protocol. If no match is found for the requested
  // protocol it will try to find matches on any protocol.
  // It can return the NULL probe.
  ServiceProbe *getProbeByName(const char *name, int proto);
  std::vector<ServiceProbe *> probes; // All the probes except nullProbe
  ServiceProbe *nullProbe; // No probe text - just waiting for banner

  // Before this function is called, the fallbacks exist as unparsed
  // comma-separated strings in the fallbackStr field of each probe.
  // This function fills out the fallbacks array in each probe with
  // an ordered list of pointers to which probes to try. This is both for
  // efficiency and to deal with odd cases like the NULL probe and falling
  // back to probes later in the file. This function also free()s all the
  // fallbackStrs.
  void compileFallbacks();

  int isExcluded(unsigned short port, int proto);
  bool excluded_seen;
  struct scan_lists excludedports;

  static AllProbes *service_scan_init(void);
  static void service_scan_free(void);
  static int check_excluded_port(unsigned short port, int proto);
protected:
  static AllProbes *global_AP;
};

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

/* Parses the given nmap-service-probes file into the AP class Must
   NOT be made static because I have external maintenance tools
   (servicematch) which use this */
void parse_nmap_service_probe_file(AllProbes *AP, char *filename);

/* Execute a service fingerprinting scan against all open ports of the
   Targets specified. */
int service_scan(std::vector<Target *> &Targets);

#endif /* SERVICE_SCAN_H */