portlist.cc

/***************************************************************************
 * portlist.cc -- Functions for manipulating various lists of ports        *
 * maintained internally by Nmap.                                          *
 *                                                                         *
 ***********************IMPORTANT NMAP LICENSE TERMS************************
 *                                                                         *
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 ***************************************************************************/

/* $Id$ */


#include "portlist.h"
#include "nmap_error.h"
#include "nmap.h"
#include "NmapOps.h"

using namespace std;

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

extern NmapOps o;  /* option structure */

Port::Port() {
  portno = proto = 0;
  owner = NULL;
  rpc_status = RPC_STATUS_UNTESTED;
  rpc_program = rpc_lowver = rpc_highver = 0;
  state = confidence = 0;
  next = NULL;
  serviceprobe_results = PROBESTATE_INITIAL;
  serviceprobe_service = NULL;
  serviceprobe_product = serviceprobe_version = serviceprobe_extrainfo = NULL;
  serviceprobe_hostname = serviceprobe_ostype = serviceprobe_devicetype = NULL;
  serviceprobe_tunnel = SERVICE_TUNNEL_NONE;
  serviceprobe_fp = NULL;
}

Port::~Port() {
 if (owner)
   free(owner);
 if (serviceprobe_product)
   free(serviceprobe_product);
 if (serviceprobe_version)
   free(serviceprobe_version);
 if (serviceprobe_extrainfo)
   free(serviceprobe_extrainfo);
 if (serviceprobe_hostname)
   free(serviceprobe_hostname);
 if (serviceprobe_ostype)
   free(serviceprobe_ostype);
 if (serviceprobe_devicetype)
   free(serviceprobe_devicetype);
 if (serviceprobe_service)
   free(serviceprobe_service);
 if (serviceprobe_fp)
   free(serviceprobe_fp);
}

// Uses the sd->{product,version,extrainfo} if available to fill
// out sd->fullversion.  If unavailable, it will be set to zero length.
static void populateFullVersionString(struct serviceDeductions *sd) {
  char *dst = sd->fullversion;
  unsigned int spaceleft = sizeof(sd->fullversion) - 1;

  dst[0] = '\0';

  if (sd->product && spaceleft >= strlen(sd->product)) {
    strncat(dst, sd->product, spaceleft);
    spaceleft -= strlen(sd->product);
  }

  if (sd->version && spaceleft >= (strlen(sd->version) + 1)) {
    strncat(dst, " ", spaceleft);
    strncat(dst, sd->version, spaceleft);
    spaceleft -= strlen(sd->version) + 1;
  }

  if (sd->extrainfo && spaceleft >= (strlen(sd->extrainfo) + 3)) {
    strncat(dst, " (", spaceleft);
    strncat(dst, sd->extrainfo, spaceleft);
    strncat(dst, ")", spaceleft);
    spaceleft -= strlen(sd->extrainfo) + 3;
  }

}


// pass in an allocated struct serviceDeductions (don't wory about
// initializing, and you don't have to free any inernal ptrs.  See the
// serviceDeductions definition for the fields that are populated.
// Returns 0 if at least a name is available.
int Port::getServiceDeductions(struct serviceDeductions *sd) {
  struct servent *service;

  assert(sd);
  memset(sd, 0, sizeof(struct serviceDeductions));
  sd->service_fp = serviceprobe_fp;
  sd->service_tunnel = serviceprobe_tunnel;
  sd->rpc_status = rpc_status;
  sd->rpc_program = rpc_program;
  sd->rpc_lowver = rpc_lowver;
  sd->rpc_highver = rpc_highver;

  // First priority is RPC
  if (rpc_status == RPC_STATUS_UNKNOWN || rpc_status == RPC_STATUS_GOOD_PROG ) {
    assert(serviceprobe_service);
    sd->name = serviceprobe_service;
    sd->name_confidence = (rpc_status == RPC_STATUS_UNKNOWN)? 8 : 10;
    sd->dtype = SERVICE_DETECTION_PROBED; // RPC counts as probed
    sd->version = serviceprobe_version;
    sd->extrainfo = serviceprobe_extrainfo;
    sd->hostname = serviceprobe_hostname;
    sd->ostype = serviceprobe_ostype;
    sd->devicetype = serviceprobe_devicetype;
    populateFullVersionString(sd);
    return 0;
  } else if (serviceprobe_results == PROBESTATE_FINISHED_HARDMATCHED
	     || serviceprobe_results == PROBESTATE_FINISHED_SOFTMATCHED) {
    assert(serviceprobe_service);
    sd->dtype = SERVICE_DETECTION_PROBED;
    sd->name = serviceprobe_service;
    sd->name_confidence = 10;
    sd->product = serviceprobe_product;
    sd->version = serviceprobe_version;
    sd->extrainfo = serviceprobe_extrainfo;
    sd->hostname = serviceprobe_hostname;
    sd->ostype = serviceprobe_ostype;
    sd->devicetype = serviceprobe_devicetype;
    populateFullVersionString(sd);
    return 0;
  } else if (serviceprobe_results == PROBESTATE_EXCLUDED) {
    service = nmap_getservbyport(htons(portno), (proto == IPPROTO_TCP)? "tcp" : "udp");

    if (service) sd->name = service->s_name;

    sd->name_confidence = 2;  // Since we didn't even check it, we aren't very confident
    sd->dtype = SERVICE_DETECTION_TABLE;
    sd->product = serviceprobe_product;  // Should have a string that says port was excluded
    populateFullVersionString(sd);
    return 0;
  } else if (serviceprobe_results == PROBESTATE_FINISHED_TCPWRAPPED) {
    sd->dtype = SERVICE_DETECTION_PROBED;
    sd->name = "tcpwrapped";
    sd->name_confidence = 8;
    return 0;
  }

  // So much for service detection or RPC.  Maybe we can find it in the file
  service = nmap_getservbyport(htons(portno), (proto == IPPROTO_TCP)? "tcp" : "udp");
  if (service) {
    sd->dtype = SERVICE_DETECTION_TABLE;
    sd->name = service->s_name;
    sd->name_confidence = 3;
    return 0;
  }
  
  // Couldn't find it.  [shrug]
  return -1;

}


// 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 neccessary, and cleaning up any unprinable
// 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 ).
void Port::setServiceProbeResults(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 char *fingerprint) {

  int slen;
  serviceprobe_results = sres;
  unsigned char *p;
  serviceprobe_tunnel = tunnel;
  if (sname) serviceprobe_service = strdup(sname);
  if (fingerprint) serviceprobe_fp = strdup(fingerprint);

  if (product) {
    slen = strlen(product);
    if (slen > 64) slen = 64;
    serviceprobe_product = (char *) safe_malloc(slen + 1);
    memcpy(serviceprobe_product, product, slen);
    serviceprobe_product[slen] = '\0';
    p = (unsigned char *) serviceprobe_product;
    while(*p) {
      if (!isprint((int)*p)) *p = '.';
      p++;
    }
  }

  if (version) {
    slen = strlen(version);
    if (slen > 64) slen = 64;
    serviceprobe_version = (char *) safe_malloc(slen + 1);
    memcpy(serviceprobe_version, version, slen);
    serviceprobe_version[slen] = '\0';
    p = (unsigned char *) serviceprobe_version;
    while(*p) {
      if (!isprint((int)*p)) *p = '.';
      p++;
    }
  }

  if (extrainfo) {
    slen = strlen(extrainfo);
    if (slen > 128) slen = 128;
    serviceprobe_extrainfo = (char *) safe_malloc(slen + 1);
    memcpy(serviceprobe_extrainfo, extrainfo, slen);
    serviceprobe_extrainfo[slen] = '\0';
    p = (unsigned char *) serviceprobe_extrainfo;
    while(*p) {
      if (!isprint((int)*p)) *p = '.';
      p++;
    }
  }

  if (hostname) {
    slen = strlen(hostname);
    if (slen > 64) slen = 64;
    serviceprobe_hostname = (char *) safe_malloc(slen + 1);
    memcpy(serviceprobe_hostname, hostname, slen);
    serviceprobe_hostname[slen] = '\0';
    p = (unsigned char *) serviceprobe_hostname;
    while(*p) {
      if (!isprint((int)*p)) *p = '.';
      p++;
    }
  }

  if (ostype) {
    slen = strlen(ostype);
    if (slen > 64) slen = 64;
    serviceprobe_ostype = (char *) safe_malloc(slen + 1);
    memcpy(serviceprobe_ostype, ostype, slen);
    serviceprobe_ostype[slen] = '\0';
    p = (unsigned char *) serviceprobe_ostype;
    while(*p) {
      if (!isprint((int)*p)) *p = '.';
      p++;
    }
  }
  
  if (devicetype) {
    slen = strlen(devicetype);
    if (slen > 64) slen = 64;
    serviceprobe_devicetype = (char *) safe_malloc(slen + 1);
    memcpy(serviceprobe_devicetype, devicetype, slen);
    serviceprobe_devicetype[slen] = '\0';
    p = (unsigned char *) serviceprobe_devicetype;
    while(*p) {
      if (!isprint((int)*p)) *p = '.';
      p++;
    }
  }

}

/* Sets the results of an RPC scan.  if rpc_status is not
   RPC_STATUS_GOOD_PROGRAM, pass 0 for the other args.  This function
   takes care of setting the port's service and version appropriately. */
void Port::setRPCProbeResults(int rpcs, unsigned long rpcp, 
			unsigned int rpcl, unsigned int rpch) {
  rpc_status = rpcs;
  const char *newsvc;
  char verbuf[128];

  rpc_status = rpcs;
  if (rpc_status == RPC_STATUS_GOOD_PROG) {
    rpc_program = rpcp;
    rpc_lowver = rpcl;
    rpc_highver = rpch;

    // Now set the service/version info
    newsvc = nmap_getrpcnamebynum(rpcp);
    if (!newsvc) newsvc = "rpc.unknownprog"; // should never happen
    if (serviceprobe_service)
      free(serviceprobe_service);
    serviceprobe_service = strdup(newsvc);
    serviceprobe_product = strdup(newsvc);
    if (rpc_lowver == rpc_highver)
      snprintf(verbuf, sizeof(verbuf), "%i", rpc_lowver);
    else
      snprintf(verbuf, sizeof(verbuf), "%i-%i", rpc_lowver, rpc_highver);
    serviceprobe_version = strdup(verbuf);
    snprintf(verbuf, sizeof(verbuf), "rpc #%li", rpc_program);
    serviceprobe_extrainfo = strdup(verbuf);
  } else if (rpc_status == RPC_STATUS_UNKNOWN) {
    if (serviceprobe_service)
      free(serviceprobe_service);
    
    serviceprobe_service = strdup("rpc.unknown");
  }
}

PortList::PortList() {
  memset(state_counts, 0, sizeof(state_counts));
  memset(state_counts_udp, 0, sizeof(state_counts_udp));
  memset(state_counts_tcp, 0, sizeof(state_counts_tcp));
  memset(state_counts_ip, 0, sizeof(state_counts_ip));
  numports = 0;
  idstr = NULL;
}

PortList::~PortList() {

  for(map<u16,Port*>::iterator iter = tcp_ports.begin(); iter != tcp_ports.end(); iter++)
     {
        delete iter->second;
     }
  

  for(map<u16,Port*>::iterator iter = udp_ports.begin(); iter != udp_ports.end(); iter++)
     {
        delete iter->second;
     }

  for(map<u16,Port*>::iterator iter = ip_prots.begin(); iter != ip_prots.end(); iter++)
     {
        delete iter->second;
     }

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

}


int PortList::addPort(u16 portno, u8 protocol, char *owner, int state) {
  Port *current = NULL;
  map < u16, Port* > *portarray = NULL;  // This has to be a pointer so that we change the original and not a copy
  char msg[128];

  assert(state < PORT_HIGHEST_STATE);

  if ((state == PORT_OPEN && o.verbose) || (o.debugging > 1)) {
    if (owner && *owner) {
      snprintf(msg, sizeof(msg), " (owner: %s)", owner);
    } else msg[0] = '\0';
    
    log_write(LOG_STDOUT, "Discovered %s port %hu/%s%s%s\n",
	      statenum2str(state), portno, 
	      proto2ascii(protocol), msg, 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("addPort: attempt to add port number %d with illegal state %d\n", portno, state);

  if (protocol == IPPROTO_TCP) {
     portarray = &tcp_ports;
  } else if (protocol == IPPROTO_UDP) {
    portarray = &udp_ports;
  } else if (protocol == IPPROTO_IP) {
    assert(portno < 256);
    portarray = &ip_prots;
  } else fatal("addPort: attempted port insertion with invalid protocol");

  if (portarray->find(portno) == portarray->end()) {
    /* We must discount our statistics from the old values.  Also warn
       if a complete duplicate */
    current = (*portarray)[portno];    
    if (o.debugging && current->state == state && (!owner || !*owner)) {
      error("Duplicate port (%hu/%s)\n", portno, proto2ascii(protocol));
    } 
    state_counts[current->state]--;
    if (current->proto == IPPROTO_TCP) {
      state_counts_tcp[current->state]--;
    } else if (current->proto == IPPROTO_UDP) {
      state_counts_udp[current->state]--;
    } else
      state_counts_ip[current->state]--;
  } else {
    current = new Port();
    (*portarray)[portno] = current;
    numports++;
    current->portno = portno;
  }
  
  state_counts[state]++;
  current->state = state;
  if (protocol == IPPROTO_TCP) {
    state_counts_tcp[state]++;
  } else if (protocol == IPPROTO_UDP) {
    state_counts_udp[state]++;
  } else
    state_counts_ip[state]++;
  current->proto = protocol;

  if (owner && *owner) {
    if (current->owner)
      free(current->owner);
    current->owner = strdup(owner);
  }
  
  /*
  printf("\nCurrent Port List\n");
  
  for(map<u16,Port*>::iterator iter = (*portarray).begin(); iter != (*portarray).end(); iter++)
    printf("(%d %d) ", iter->first, iter->second->portno);
  printf("\n");
  */
  

  return 0; /*success */
}

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

  printf("Removed %d\n", portno);

  if (protocol == IPPROTO_TCP) {
   answer = tcp_ports[portno];
   tcp_ports.erase(portno);
  }

  if (protocol == IPPROTO_UDP) {  
    answer = udp_ports[portno];
    udp_ports.erase(portno);
  } else if (protocol == IPPROTO_IP) {
    answer = ip_prots[portno];
    ip_prots.erase(portno);
  }

  if (!answer)
    return -1;

  if (o.verbose) {  
    log_write(LOG_STDOUT, "Deleting port %hu/%s, which we thought was %s\n",
	      portno, proto2ascii(answer->proto),
	      statenum2str(answer->state));
    log_flush(LOG_STDOUT);
  }    

  delete answer;
  return 0;
}

  /* Saves an identification string for the target containing these
     ports (an IP addrss 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);
}

Port *PortList::lookupPort(u16 portno, u8 protocol) {

  if (protocol == IPPROTO_TCP)
    return tcp_ports[portno];

  if (protocol == IPPROTO_UDP)
    return udp_ports[portno];

  if (protocol == IPPROTO_IP)
    return ip_prots[portno];

  return NULL;
}

int PortList::getIgnoredPortState() {
  int ignored = PORT_UNKNOWN;
  int ignoredNum = 0;
  int i;
  for(i=0; i < PORT_HIGHEST_STATE; i++) {
    if (i == PORT_OPEN || i == PORT_UNKNOWN || i == PORT_TESTING || 
	i == PORT_FRESH) continue; /* Cannot be ignored */
    if (state_counts[i] > ignoredNum) {
      ignored = i;
      ignoredNum = state_counts[i];
    }
  }

  if (state_counts[ignored] < 15)
    ignored = PORT_UNKNOWN;

  return ignored;
}

/* 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 or IPPROTO_UDP for allowed_protocol.  A 0 for
   allowed_protocol matches either.  allowed_state works in the same
   fashion as allowed_protocol. This function returns ports in numeric
   order from lowest to highest, except that if you ask for both TCP &
   UDP, every TCP port will be returned before we start returning UDP
   ports.  */

Port *PortList::nextPort(Port *afterthisport, 
			 u8 allowed_protocol, int allowed_state, 
			 bool allow_portzero) {
  
  /* These two are chosen because they come right "before" port 1/tcp */
  map<u16,Port*>::iterator iter;
  
  if (afterthisport) {
    if (afterthisport->proto == IPPROTO_TCP) {
      iter = tcp_ports.find(afterthisport->portno);
      assert(iter != tcp_ports.end());
      iter++;
      while(iter != tcp_ports.end()) {
	if (!allowed_state || iter->second->state == allowed_state)
	  return iter->second;
	iter++;
      }
      /* No more TCP ports ... */
      if (allowed_protocol != 0)
	return NULL;
      
      iter = udp_ports.begin();
    } else {
      assert(afterthisport->proto == IPPROTO_UDP);
      iter = udp_ports.find(afterthisport->portno);
      assert(iter != udp_ports.end());
      iter++;
    }
    while(iter != udp_ports.end()) {
      if (!allowed_state || iter->second->state == allowed_state)
	return iter->second;
      iter++;
    }
    return NULL;
  } 

  // First-time call - try TCP ports first
  if (allowed_protocol == 0 || allowed_protocol == IPPROTO_TCP) {
    iter = tcp_ports.begin();
    while (iter != tcp_ports.end()) {
      if (!allowed_state || iter->second->state == allowed_state)
	return iter->second;
      iter++;
    }
  }
  
  // Maybe we'll have better luck with UDP
  if (allowed_protocol == 0 || allowed_protocol == IPPROTO_UDP) {
    iter = udp_ports.begin();
    while (iter != udp_ports.end()) {
      if (!allowed_state || iter->second->state == allowed_state)
	return iter->second;
      iter++;
    }
  }
  
  // Nuthing found
  return NULL;
}


// 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;
  u16 pop_ports[] = { 21, 22, 23, 25, 53, 80, 113, 256, 389, 443, 554, 636, 1723, 3389 };
  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;
      }
    }
  }
}