path: root/portlist.cc

/***************************************************************************
 * portlist.cc -- Functions for manipulating various lists of ports        *
 * maintained internally by Nmap.                                          *
 *                                                                         *
 ***********************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.
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 *
 * The free version of Nmap is distributed in the hope that it will be
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 *
 ***************************************************************************/

/* $Id$ */


#include "nmap.h"
#include "portlist.h"
#include "nmap_error.h"
#include "NmapOps.h"
#include "services.h"
#include "protocols.h"
#include "tcpip.h"
#include "string_pool.h"
#include "libnetutil/netutil.h"

#if HAVE_STRINGS_H
#include <strings.h>
#endif /* HAVE_STRINGS_H */

extern NmapOps o;  /* option structure */

Port::Port() {
  portno = proto = 0;
  state = 0;
  service = NULL;
  state_reason_init(&reason);
}

void serviceDeductions::erase() {
  std::vector<char *>::iterator it;

  if (this->product)
    free(this->product);
  if (this->version)
    free(this->version);
  if (this->extrainfo)
    free(this->extrainfo);
  if (this->hostname)
    free(this->hostname);
  if (this->ostype)
    free(this->ostype);
  if (this->devicetype)
    free(this->devicetype);
  if (this->service_fp)
    free(this->service_fp);
  // For now, always free CPE strings
  for (it = this->cpe.begin(); it != this->cpe.end(); it++)
    free(*it);
  this->cpe.clear();

  this->name = NULL;
  this->name_confidence = 0;
  this->product = NULL;
  this->version = NULL;
  this->extrainfo = NULL;
  this->hostname = NULL;
  this->ostype = NULL;
  this->devicetype = NULL;
  this->service_tunnel = SERVICE_TUNNEL_NONE;
  this->service_fp = NULL;
  this->dtype = SERVICE_DETECTION_TABLE;
}

void Port::freeScriptResults(void)
{
#ifndef NOLUA
    for (ScriptResults::iterator it = scriptResults.begin();
        it != scriptResults.end(); it++) {
      delete (*it);
    }
    scriptResults.clear();
#endif
}

/* Fills in namebuf (as long as there is space in buflen) with the
   Name nmap normal output will use to describe the port.  This takes
   into account to confidence level, any SSL tunneling, etc.  Truncates
   namebuf to 0 length if there is no room.*/
void Port::getNmapServiceName(char *namebuf, int buflen) const {
  const char *tunnel_prefix;
  const char *service_name;
  int len;

  if (service != NULL && service->service_tunnel == SERVICE_TUNNEL_SSL)
    tunnel_prefix = "ssl/";
  else
    tunnel_prefix = "";

  if (service != NULL && service->name != NULL) {
    service_name = service->name;
  } else {
    const struct nservent *service;

    service = nmap_getservbyport(portno, proto);
    if (service != NULL)
      service_name = service->s_name;
    else
      service_name = NULL;
  }

  if (service_name != NULL && strcmp(service_name, "unknown") != 0) {
    /* The port has a name and the name is not "unknown". How confident are we? */
    if (o.servicescan && state == PORT_OPEN && (service == NULL || service->name_confidence <= 5))
      len = Snprintf(namebuf, buflen, "%s%s?", tunnel_prefix, service_name);
    else
      len = Snprintf(namebuf, buflen, "%s%s", tunnel_prefix, service_name);
  } else {
    len = Snprintf(namebuf, buflen, "%sunknown", tunnel_prefix);
  }
  if (len >= buflen || len < 0) {
    namebuf[0] = '\0';
    return;
  }

}

serviceDeductions::serviceDeductions() {
  name = NULL;
  name_confidence = 0;
  product = NULL;
  version = NULL;
  extrainfo = NULL;
  hostname = NULL;
  ostype = NULL;
  devicetype = NULL;
  service_tunnel = SERVICE_TUNNEL_NONE;
  service_fp = NULL;
  dtype = SERVICE_DETECTION_TABLE;
}

// Uses the sd->{product,version,extrainfo} if available to fill
// out sd->fullversion.  If unavailable, it will be set to zero length.
void serviceDeductions::populateFullVersionString(char *buf, size_t n) const {
  char *dst = buf;
  unsigned int spaceleft = n - 1; // Leave room for \0
  int needpad = 0;  // Do we need to pad a space between the next template?

  dst[0] = '\0';

  /* Sometimes there is really great product/version/extra information
   * available that won't quite fit.  Rather than just drop that information
   * this routine will truncate the string that is too long with "...".
   * If there are fewer than 8 characters left don't bother and just skip
   * that bit of information.
   */

  if (product && spaceleft >= 8) {
    if (spaceleft < strlen(product)) {
      strncat(dst, product, spaceleft - 3);  // Leave room for "..."
      strncat(dst, "...", spaceleft);
      spaceleft = 0;
    }
    else {
      strncat(dst, product, spaceleft);
      spaceleft -= strlen(product);
    }
    needpad = 1;
  }

  if (version && spaceleft >= 8) {
    if (needpad) {
      strncat(dst, " ", spaceleft);
      spaceleft--;
    }

    if (spaceleft < strlen(version)) {
      strncat(dst, version, spaceleft - 3);
      strncat(dst, "...", spaceleft);
      spaceleft = 0;
    }
    else {
      strncat(dst, version, spaceleft);
      spaceleft -= strlen(version);
    }
    needpad = 1;
  }

  if (extrainfo && spaceleft >= 8) {
    if (needpad) {
      strncat(dst, " ", spaceleft);
      spaceleft--;
    }
    // This time we need to truncate inside of the () so we have spaceleft - 2
    strncat(dst, "(", spaceleft);
    if (spaceleft - 2 < strlen(extrainfo)) {
      strncat(dst, extrainfo, spaceleft - 5);
      strncat(dst, "...", spaceleft - 2);
      spaceleft = 1;  // Fit the paren
    }
    else {
      strncat(dst, extrainfo, spaceleft);
      spaceleft -= (strlen(extrainfo) + 2);
    }
    strncat(dst, ")", spaceleft);
    spaceleft--;
  }

}


// pass in an allocated struct serviceDeductions (don't worry about
// initializing, and you don't have to free any internal ptrs.  See the
// serviceDeductions definition for the fields that are populated.
void PortList::getServiceDeductions(u16 portno, int protocol, struct serviceDeductions *sd) const {
  const Port *port;

  port = lookupPort(portno, protocol);
  if (port == NULL || port->service == NULL) {
    const struct nservent *service;

    /* Look up the service name. */
    *sd = serviceDeductions();
    service = nmap_getservbyport(portno, protocol);
    if (service != NULL)
      sd->name = service->s_name;
    else
      sd->name = NULL;
    sd->name_confidence = 3;
  } else {
    *sd = *port->service;
  }
}


// sname should be NULL if sres is not
// PROBESTATE_FINISHED_MATCHED. product,version, and/or extrainfo
// will be NULL if unavailable. Note that this function makes its
// own copy of sname and product/version/extrainfo.  This function
// also takes care of truncating the version strings to a
// 'reasonable' length if necessary, and cleaning up any unprintable
// chars. (these tests are to avoid annoying DOS (or other) attacks
// by malicious services).  The fingerprint should be NULL unless
// one is available and the user should submit it.  tunnel must be
// SERVICE_TUNNEL_NULL (normal) or SERVICE_TUNNEL_SSL (means ssl was
// detected and we tried to tunnel through it ).
static char *cstringSanityCheck(const char* string, int len) {
  char *result;
  int slen;

  if(!string)
          return NULL;

  slen = strlen(string);
  if (slen > len) slen = len;
  result = (char *) safe_malloc(slen + 1);
  memcpy(result, string, slen);
  result[slen] = '\0';
  replacenonprintable(result, slen, '.');
  return result;
}

void PortList::setServiceProbeResults(u16 portno, int protocol,
  enum serviceprobestate sres, const char *sname,
  enum service_tunnel_type tunnel, const char *product, const char *version,
  const char *extrainfo, const char *hostname, const char *ostype,
  const char *devicetype, const std::vector<const char *> *cpe,
  const char *fingerprint) {
  std::vector<char *>::iterator it;
  Port *port;
  char *p;

  port = createPort(portno, protocol);
  if (port->service == NULL)
    port->service = new serviceDeductions;
  else
    port->service->erase();

  if (sres == PROBESTATE_FINISHED_HARDMATCHED
      || sres == PROBESTATE_FINISHED_SOFTMATCHED) {
    port->service->dtype = SERVICE_DETECTION_PROBED;
    port->service->name_confidence = 10;
  } else if (sres == PROBESTATE_FINISHED_TCPWRAPPED) {
    port->service->dtype = SERVICE_DETECTION_PROBED;
    if (sname == NULL)
      sname = "tcpwrapped";
    port->service->name_confidence = 8;
  } else {
    /* PROBESTATE_FINISHED_NOMATCH, PROBESTATE_EXCLUDED, PROBESTATE_INCOMPLETE.
       Just look up the service name if none is provided. */
    if (sname == NULL) {
      const struct nservent *service;
      service = nmap_getservbyport(portno, protocol);
      if (service != NULL)
        sname = service->s_name;
    }
    port->service->dtype = SERVICE_DETECTION_TABLE;
    port->service->name_confidence = 3;  // Since we didn't even check it, we aren't very confident
  }

  // port->serviceprobe_results = sres;
  port->service->service_tunnel = tunnel;

  if (sname)
    port->service->name = string_pool_insert(sname);
  else
    port->service->name = NULL;

  if (fingerprint)
    port->service->service_fp = strdup(fingerprint);
  else
    port->service->service_fp = NULL;

  port->service->product = cstringSanityCheck(product, 80);
  port->service->version = cstringSanityCheck(version, 80);
  port->service->extrainfo = cstringSanityCheck(extrainfo, 256);
  port->service->hostname = cstringSanityCheck(hostname, 80);
  port->service->ostype = cstringSanityCheck(ostype, 32);
  port->service->devicetype = cstringSanityCheck(devicetype, 32);

  if (cpe) {
    std::vector<const char *>::const_iterator cit;

    for (cit = cpe->begin(); cit != cpe->end(); cit++) {
      p = cstringSanityCheck(*cit, 80);
      if (p != NULL)
        port->service->cpe.push_back(p);
    }
  }
}


#ifndef NOLUA
void PortList::addScriptResult(u16 portno, int protocol, ScriptResult *sr) {
  Port *port;

  port = createPort(portno, protocol);

  port->scriptResults.insert(sr);
}
#endif

/*****************************************************************************/
/* Convert protocol name from in.h to enum portlist_proto.
 * So IPPROTO_TCP will be changed to PORTLIST_PROTO_TCP and so on. */
#define INPROTO2PORTLISTPROTO(p)		\
  ((p)==IPPROTO_TCP ? PORTLIST_PROTO_TCP :	\
   (p)==IPPROTO_UDP ? PORTLIST_PROTO_UDP :	\
   (p)==IPPROTO_SCTP ? PORTLIST_PROTO_SCTP :	\
   PORTLIST_PROTO_IP)

#define PORTLISTPROTO2INPROTO(p)		\
  ((p)==PORTLIST_PROTO_TCP ? IPPROTO_TCP :	\
   (p)==PORTLIST_PROTO_UDP ? IPPROTO_UDP :	\
   (p)==PORTLIST_PROTO_SCTP ? IPPROTO_SCTP :	\
   IPPROTO_IP)


PortList::PortList() {
  int proto;
  memset(state_counts_proto, 0, sizeof(state_counts_proto));
  memset(port_list, 0, sizeof(port_list));

  for(proto=0; proto < PORTLIST_PROTO_MAX; proto++) {
    if(port_list_count[proto] > 0)
      port_list[proto] = (Port**) safe_zalloc(sizeof(Port*)*port_list_count[proto]);
    default_port_state[proto].proto = PORTLISTPROTO2INPROTO(proto);
    default_port_state[proto].reason.reason_id = ER_NORESPONSE;
    state_counts_proto[proto][default_port_state[proto].state] = port_list_count[proto];
  }

  numscriptresults = 0;
  idstr = NULL;
}

PortList::~PortList() {
  int proto, i;

  if (idstr) {
    free(idstr);
    idstr = NULL;
  }

  for(proto=0; proto < PORTLIST_PROTO_MAX; proto++) { // for every protocol
    if(port_list[proto]) {
      for(i=0; i < port_list_count[proto]; i++) { // free every Port
        Port *port = port_list[proto][i];
        if(port) {
          if (port->service) {
            port->service->erase();
            delete port->service;
          }
          port->freeScriptResults();
          delete port;
        }
      }
      free(port_list[proto]);
    }
  }
}

void PortList::setDefaultPortState(u8 protocol, int state) {
  int proto = INPROTO2PORTLISTPROTO(protocol);
  int i;

  for (i = 0; i < port_list_count[proto]; i++) {
    if (port_list[proto][i] == NULL) {
      state_counts_proto[proto][default_port_state[proto].state]--;
      state_counts_proto[proto][state]++;
    }
  }

  default_port_state[proto].state = state;
}

void PortList::setPortState(u16 portno, u8 protocol, int state) {
  const Port *oldport;
  Port *current;
  int proto = INPROTO2PORTLISTPROTO(protocol);

  assert(state < PORT_HIGHEST_STATE);

  if ((state == PORT_OPEN && o.verbose) || (o.debugging > 1)) {
    log_write(LOG_STDOUT, "Discovered %s port %hu/%s%s\n",
              statenum2str(state), portno,
              proto2ascii_lowercase(protocol), idstr? idstr : "");
    log_flush(LOG_STDOUT);
  }


  /* Make sure state is OK */
  if (state != PORT_OPEN && state != PORT_CLOSED && state != PORT_FILTERED &&
      state != PORT_UNFILTERED && state != PORT_OPENFILTERED &&
      state != PORT_CLOSEDFILTERED)
    fatal("%s: attempt to add port number %d with illegal state %d\n", __func__, portno, state);

  assert(protocol!=IPPROTO_IP || portno<256);

  oldport = lookupPort(portno, protocol);
  if (oldport != NULL) {
    /* We must discount our statistics from the old values.  Also warn
       if a complete duplicate */
    if (o.debugging && oldport->state == state) {
      error("Duplicate port (%hu/%s)", portno, proto2ascii_lowercase(protocol));
    }
    state_counts_proto[proto][oldport->state]--;
  } else {
    state_counts_proto[proto][default_port_state[proto].state]--;
  }
  current = createPort(portno, protocol);

  current->state = state;
  state_counts_proto[proto][state]++;

  if(state == PORT_FILTERED || state == PORT_OPENFILTERED)
    setStateReason(portno, protocol, ER_NORESPONSE, 0, NULL);
  return;
}

int PortList::getPortState(u16 portno, u8 protocol) {
  const Port *port;

  port = lookupPort(portno, protocol);
  if (port == NULL)
    return default_port_state[INPROTO2PORTLISTPROTO(protocol)].state;

  return port->state;
}

/* Return true if nothing special is known about this port; i.e., it's in the
   default state as defined by setDefaultPortState and every other data field is
   unset. */
bool PortList::portIsDefault(u16 portno, u8 protocol) {
  return lookupPort(portno, protocol) == NULL;
}

  /* Saves an identification string for the target containing these
     ports (an IP address might be a good example, but set what you
     want).  Only used when printing new port updates.  Optional.  A
     copy is made. */
void PortList::setIdStr(const char *id) {
  int len = 0;
  if (idstr) free(idstr);
  if (!id) { idstr = NULL; return; }
  len = strlen(id);
  len += 5; // " on " + \0
  idstr = (char *) safe_malloc(len);
  Snprintf(idstr, len, " on %s", id);
}


int PortList::getStateCounts(int protocol, int state) const {
  return state_counts_proto[INPROTO2PORTLISTPROTO(protocol)][state];
}

int PortList::getStateCounts(int state) const {
  int sum=0, proto;
  for(proto=0; proto < PORTLIST_PROTO_MAX; proto++)
    sum += getStateCounts(PORTLISTPROTO2INPROTO(proto), state);
  return(sum);
}

  /* A function for iterating through the ports.  Give NULL for the
   first "afterthisport".  Then supply the most recent returned port
   for each subsequent call.  When no more matching ports remain, NULL
   will be returned.  To restrict returned ports to just one protocol,
   specify IPPROTO_TCP, IPPROTO_UDP or IPPROTO_SCTP for
   allowed_protocol. A TCPANDUDPANDSCTP for allowed_protocol matches
   either. A 0 for allowed_state matches all possible states. This
   function returns ports in numeric order from lowest to highest,
   except that if you ask for both TCP, UDP & SCTP, every TCP port
   will be returned before we start returning UDP and SCTP ports */
Port *PortList::nextPort(const Port *cur, Port *next,
                         int allowed_protocol, int allowed_state) const {
  int proto;
  int mapped_pno;
  Port *port;

  if (cur) {
    proto = INPROTO2PORTLISTPROTO(cur->proto);
    assert(port_map[proto]!=NULL); // Hmm, it's not possible to handle port that doesn't have anything in map
    assert(cur->proto!=IPPROTO_IP || cur->portno<256);
    mapped_pno = port_map[proto][cur->portno];
    mapped_pno++; //  we're interested in next port after current
  } else { // running for the first time
    if (allowed_protocol == TCPANDUDPANDSCTP)
      proto = INPROTO2PORTLISTPROTO(IPPROTO_TCP);
    else if (allowed_protocol == UDPANDSCTP)
      proto = INPROTO2PORTLISTPROTO(IPPROTO_UDP);
    else
      proto = INPROTO2PORTLISTPROTO(allowed_protocol);
    mapped_pno = 0;
  }

  if(port_list[proto] != NULL) {
    for(;mapped_pno < port_list_count[proto]; mapped_pno++) {
      port = port_list[proto][mapped_pno];
      if (port && (allowed_state==0 || port->state==allowed_state)) {
        *next = *port;
        return next;
      }
      if (!port && (allowed_state==0 || default_port_state[proto].state==allowed_state)) {
        *next = default_port_state[proto];
        next->portno = port_map_rev[proto][mapped_pno];
        return next;
      }
    }
  }

  /* if all protocols, than after TCP search UDP & SCTP */
  if((!cur && allowed_protocol == TCPANDUDPANDSCTP) ||
      (cur && proto == INPROTO2PORTLISTPROTO(IPPROTO_TCP)))
    return(nextPort(NULL, next, UDPANDSCTP, allowed_state));

  /* if all protocols, than after UDP search SCTP */
  if((!cur && allowed_protocol == UDPANDSCTP) ||
      (cur && proto == INPROTO2PORTLISTPROTO(IPPROTO_UDP)))
    return(nextPort(NULL, next, IPPROTO_SCTP, allowed_state));

  return(NULL);
}

/* Convert portno and protocol into the internal indices used to index
   port_list. */
void PortList::mapPort(u16 *portno, u8 *protocol) const {
  int mapped_portno, mapped_protocol;

  mapped_protocol = INPROTO2PORTLISTPROTO(*protocol);

  if (*protocol == IPPROTO_IP)
    assert(*portno < 256);
  if(port_map[mapped_protocol]==NULL || port_list[mapped_protocol]==NULL) {
    fatal("%s(%i,%i): you're trying to access uninitialized protocol", __func__, *portno, *protocol);
  }
  mapped_portno = port_map[mapped_protocol][*portno];

  assert(mapped_portno < port_list_count[mapped_protocol]);
  assert(mapped_portno >= 0);

  *portno = mapped_portno;
  *protocol = mapped_protocol;
}

const Port *PortList::lookupPort(u16 portno, u8 protocol) const {
  mapPort(&portno, &protocol);
  return port_list[protocol][portno];
}

/* Create the port if it doesn't exist; otherwise this is like lookupPort. */
Port *PortList::createPort(u16 portno, u8 protocol) {
  Port *p;
  u16 mapped_portno;
  u8 mapped_protocol;

  mapped_portno = portno;
  mapped_protocol = protocol;
  mapPort(&mapped_portno, &mapped_protocol);

  p = port_list[mapped_protocol][mapped_portno];
  if (p == NULL) {
    p = new Port();
    p->portno = portno;
    p->proto = protocol;
    p->state = default_port_state[mapped_protocol].state;
    p->reason.reason_id = ER_NORESPONSE;
    port_list[mapped_protocol][mapped_portno] = p;
  }

  return port_list[mapped_protocol][mapped_portno];
}

int PortList::forgetPort(u16 portno, u8 protocol) {
  Port *answer = NULL;

  log_write(LOG_PLAIN, "Removed %d\n", portno);

  mapPort(&portno, &protocol);

  answer = port_list[protocol][portno];
  if (answer == NULL)
    return -1;

  state_counts_proto[protocol][answer->state]--;
  state_counts_proto[protocol][default_port_state[protocol].state]++;

  port_list[protocol][portno] = NULL;

  if (o.verbose) {
    log_write(LOG_STDOUT, "Deleting port %hu/%s, which we thought was %s\n",
              portno, proto2ascii_lowercase(answer->proto),
              statenum2str(answer->state));
    log_flush(LOG_STDOUT);
  }

  delete answer;
  return 0;
}

/* Just free memory used by PortList::port_map[]. Should be done somewhere
 * before closing nmap. */
void PortList::freePortMap() {
  int proto;

  for (proto=0; proto < PORTLIST_PROTO_MAX; proto++) {
    if (port_map[proto]) {
      free(port_map[proto]);
      port_map[proto] = NULL;
    }
    if (port_map_rev[proto]) {
      free(port_map_rev[proto]);
      port_map_rev[proto] = NULL;
    }
    port_list_count[proto] = 0;
  }
}


u16 *PortList::port_map[PORTLIST_PROTO_MAX];
u16 *PortList::port_map_rev[PORTLIST_PROTO_MAX];
int PortList::port_list_count[PORTLIST_PROTO_MAX];

/* This function must be run before any PortList object is created.
 * It must be run for every used protocol. The data in "ports"
 * should be sorted. */
void PortList::initializePortMap(int protocol, u16 *ports, int portcount) {
  int i;
  int ports_max = (protocol == IPPROTO_IP) ? 256 : 65536;
  int proto = INPROTO2PORTLISTPROTO(protocol);

  if (port_map[proto] != NULL || port_map_rev[proto] != NULL)
    fatal("%s: portmap for protocol %i already initialized", __func__, protocol);

  assert(port_list_count[proto]==0);

  /* this memory will never be freed, but this is the way it has to be. */
  port_map[proto] = (u16 *) safe_zalloc(sizeof(u16) * ports_max);
  port_map_rev[proto] = (u16 *) safe_zalloc(sizeof(u16) * portcount);

  port_list_count[proto] = portcount;

  for(i=0; i < portcount; i++) {
    port_map[proto][ports[i]] = i;
    port_map_rev[proto][i] = ports[i];
  }
  /* So now port_map should have such structure (lets scan 2nd,4th and 6th port):
   * 	port_map[0,0,1,0,2,0,3,...]	        <- indexes to port_list structure
   * 	port_list[port_2,port_4,port_6] */
}

  /* Cycles through the 0 or more "ignored" ports which should be
   consolidated for Nmap output.  They are returned sorted by the
   number of ports in the state, starting with the most common.  It
   should first be called with PORT_UNKNOWN to obtain the most popular
   ignored state (if any).  Then call with that state to get the next
   most popular one.  Returns the state if there is one, but returns
   PORT_UNKNOWN if there are no (more) states which qualify for
   consolidation */
int PortList::nextIgnoredState(int prevstate) const {

  int beststate = PORT_UNKNOWN;
  int count = 0;
  int prevcount = 0;
  int bestcount = 0;

  if (prevstate != PORT_UNKNOWN) {
    prevcount = getStateCounts(prevstate);
  }

  for(int state=0; state < PORT_HIGHEST_STATE; state++) {
    /* The state must be ignored */
    if (!isIgnoredState(state, &count))
      continue;

    /* We can't give the same state again ... */
    if (state == prevstate) continue;

    /* If a previous state was given, we must have fewer ports than
       that one, or be tied but be a larger state number */
    if (prevstate != PORT_UNKNOWN &&
        (count > prevcount ||
         (count == prevcount && state <= prevstate)))
      continue;

    /* We only qualify if we have more ports than the current best */
    if (beststate != PORT_UNKNOWN && bestcount >= count)
      continue;

    /* Yay!  We found the best state so far ... */
    beststate = state;
    bestcount = count;
  }

  return beststate;
}

/* Returns true if a state should be ignored (consolidated), false otherwise.
 * If result is true and count is provided, it will be filled with the count of
 * ports in that state. */
bool PortList::isIgnoredState(int state, int *count) const {

  int tmp_count = 0;
  if (o.debugging > 2)
    return false;

  if (state == PORT_OPEN || state == PORT_UNKNOWN || state == PORT_TESTING ||
      state == PORT_FRESH)
    return false; /* Cannot be ignored */

  if (state == PORT_OPENFILTERED && (o.verbose > 2 || o.debugging > 2))
    return false;

  tmp_count = getStateCounts(state);
  if (count != NULL) {
    *count = tmp_count;
  }
  /* If openonly, we always ignore states that don't at least have open
     as a possibility. */
  if (o.openOnly() && state != PORT_OPENFILTERED && state != PORT_UNFILTERED
      && tmp_count > 0)
    return true;

  int max_per_state = 25; // Ignore states with more ports than this
  /* We will show more ports when verbosity is requested */
  if (o.verbose || o.debugging) {
    if (o.ipprotscan)
      max_per_state *= ((o.verbose + 1) + 3 * o.debugging);
    else
      max_per_state *= ((o.verbose + 1) + 20 * o.debugging);
  }

  if (tmp_count > max_per_state)
    return true;

  return false;
}

int PortList::numIgnoredStates() const {
  int numstates = 0;
  for(int state=0; state < PORT_HIGHEST_STATE; state++) {
    if (isIgnoredState(state, NULL))
      numstates++;
  }
  return numstates;
}

int PortList::numIgnoredPorts() const {

  int numports = 0;
  int tmp = 0;
  for(int state=0; state < PORT_HIGHEST_STATE; state++) {
    if (isIgnoredState(state, &tmp))
      numports += tmp;
  }
  return numports;
}

int PortList::numPorts() const {
  int proto, num = 0;

  for (proto = 0; proto < PORTLIST_PROTO_MAX; proto++)
    num += port_list_count[proto];

  return num;
}

/* Return true if any of the ports are potentially open. */
bool PortList::hasOpenPorts() const {
  return getStateCounts(PORT_OPEN) != 0 ||
    getStateCounts(PORT_OPENFILTERED) != 0 ||
    getStateCounts(PORT_UNFILTERED) != 0;
}

/* Returns true if service scan is done and portno is found to be tcpwrapped, false otherwise */
bool PortList::isTCPwrapped(u16 portno) const {
  const Port *port = lookupPort(portno, IPPROTO_TCP);
  if (port == NULL) {
    if (o.debugging > 1) {
      log_write(LOG_STDOUT, "PortList::isTCPwrapped(%d) requested but port not in list\n", portno);
    }
    return false;
  } else if (!o.servicescan) {
    if (o.debugging > 1) {
      log_write(LOG_STDOUT, "PortList::isTCPwrapped(%d) requested but service scan was never asked to be done\n", portno);
    }
    return false;
  } else if (port->service == NULL) {
    if (o.debugging > 1) {
      log_write(LOG_STDOUT, "PortList::isTCPwrapped(%d) requested but port has not been service scanned yet\n", portno);
    }
    return false;
  } else if (port->service->name == NULL) {
    // no service match and port not listed in services file
    if (o.debugging > 1) {
      log_write(LOG_STDOUT, "PortList::isTCPwrapped(%d) requested but service has no name\n", portno);
    }
    return false;
  } else {
    return (strcmp(port->service->name,"tcpwrapped")==0);
  }
}

int PortList::setStateReason(u16 portno, u8 proto, reason_t reason, u8 ttl,
  const struct sockaddr_storage *ip_addr) {
    Port *answer = NULL;

    answer = createPort(portno, proto);

    /* set new reason and increment its count */
    answer->reason.reason_id = reason;
    if (ip_addr == NULL)
      answer->reason.ip_addr.sockaddr.sa_family = AF_UNSPEC;
    else
      answer->reason.set_ip_addr(ip_addr);
    answer->reason.ttl = ttl;
    return 0;
}

// Move some popular TCP ports to the beginning of the portlist, because
// that can speed up certain scans.  You should have already done any port
// randomization, this should prevent the ports from always coming out in the
// same order.
void random_port_cheat(u16 *ports, int portcount) {
  int allportidx = 0;
  int popportidx = 0;
  int earlyreplidx = 0;
  /* Updated 2008-12-19 from nmap-services-all.
     Top 25 open TCP ports plus 113, 554, and 256 */
  u16 pop_ports[] = {
    80, 23, 443, 21, 22, 25, 3389, 110, 445, 139,
    143, 53, 135, 3306, 8080, 1723, 111, 995, 993, 5900,
    1025, 587, 8888, 199, 1720,
    113, 554, 256
  };
  int num_pop_ports = sizeof(pop_ports) / sizeof(u16);

  for(allportidx = 0; allportidx < portcount; allportidx++) {
    // see if the currentport is a popular port
    for(popportidx = 0; popportidx < num_pop_ports; popportidx++) {
      if (ports[allportidx] == pop_ports[popportidx]) {
        // This one is popular!  Swap it near to the beginning.
        if (allportidx != earlyreplidx) {
          ports[allportidx] = ports[earlyreplidx];
          ports[earlyreplidx] = pop_ports[popportidx];
        }
        earlyreplidx++;
        break;
      }
    }
  }
}

const char *statenum2str(int state) {
  switch (state) {
  case PORT_OPEN:
    return "open";
    break;
  case PORT_FILTERED:
    return "filtered";
    break;
  case PORT_UNFILTERED:
    return "unfiltered";
    break;
  case PORT_CLOSED:
    return "closed";
    break;
  case PORT_OPENFILTERED:
    return "open|filtered";
    break;
  case PORT_CLOSEDFILTERED:
    return "closed|filtered";
    break;
  default:
    return "unknown";
    break;
  }
  return "unknown";
}