/* SAMHAIN file system integrity testing                                   */
/* Copyright (C) 2006 Rainer Wichmann                                      */
/*                                                                         */
/*  This program is free software; you can redistribute it                 */
/*  and/or modify                                                          */
/*  it under the terms of the GNU General Public License as                */
/*  published by                                                           */
/*  the Free Software Foundation; either version 2 of the License, or      */
/*  (at your option) any later version.                                    */
/*                                                                         */
/*  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          */
/*  GNU General Public License for more details.                           */
/*                                                                         */
/*  You should have received a copy of the GNU General Public License      */
/*  along with this program; if not, write to the Free Software            */
/*  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.              */

/***************************************************************************
 *
 * This file provides a module for samhain to check for open ports
 * on the local machine.
 *
 */


/* #define TEST_ONLY */
#ifndef TEST_ONLY
#include "config_xor.h"
#endif

#include <stdio.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <errno.h>
#include <unistd.h>

#define PORTCHK_VERSION "1.0"

#if defined(TEST_ONLY) || (defined(SH_USE_PORTCHECK) && (defined (SH_WITH_CLIENT) || defined (SH_STANDALONE)))


#define PORTMAP
#include <rpc/rpc.h>
#ifdef  HAVE_RPC_RPCENT_H
#include <rpc/rpcent.h>
#endif
#include <rpc/pmap_clnt.h>
#include <rpc/pmap_prot.h>
#include <netdb.h>

/*
 * struct pmaplist {
 *      struct pmap     pml_map;
 *      struct pmaplist *pml_next;
 * };
 */

/* struct pmap {
 *      long unsigned pm_prog;
 *      long unsigned pm_vers;
 *      long unsigned pm_prot;
 *      long unsigned pm_port;
 * };
 */

/* TIME_WAIT ? 60-240 seconds */

/* the size of an interface string 
 */
#define SH_INTERFACE_SIZE 16

#define SH_PORT_NOT 0
#define SH_PORT_REQ 1
#define SH_PORT_OPT 2

#define SH_PORT_MISS 0
#define SH_PORT_ISOK 1
#define SH_PORT_UNKN 2

#define SH_PORT_NOREPT 0
#define SH_PORT_REPORT 1

struct sh_portentry {
  int  port;
  char interface[SH_INTERFACE_SIZE];
  char * service;
  char * error;
  int  flag;    /* required or not */
  int  status;  /* missing or not  */
  struct sh_portentry * next;
};

static struct sh_portentry * portlist_tcp = NULL;
static struct sh_portentry * portlist_udp = NULL;

#define SH_PORTCHK_INTERVAL 300

static int sh_portchk_check_udp = 1;
static int sh_portchk_active    = 1;
static int sh_portchk_interval  = SH_PORTCHK_INTERVAL;
#if !defined(TEST_ONLY)

#define FIL__ _("sh_portcheck.c")
#include "samhain.h"
#include "sh_error.h"
#include "sh_mem.h"
#include "sh_utils.h"
#include "sh_modules.h"

static int sh_portchk_severity  = SH_ERR_SEVERE;
#endif

/* Exported interface to add required ports as 'iface:portlist'
 */
static int sh_portchk_add_required (const char * str);

/* Exported interface to add optional ports as 'iface:portlist'
 */
static int sh_portchk_add_optional (const char * str);

/* Exported interface to add an ethernet interface
 */
static int sh_portchk_add_interface (const char * str);


#ifndef TEST_ONLY

static int sh_portchk_set_interval (const char * c)
{
  int retval = 0;
  long val;

  SL_ENTER(_("sh_portchk_set_interval"));
  val = strtol (c, (char **)NULL, 10);
  if (val <= 0)
    {
      sh_error_handle ((-1), FIL__, __LINE__, EINVAL, MSG_EINVALS,
		       _("port check interval"), c);
      retval = -1;
    }

  val = (val <= 0 ? 60 : val);

  sh_portchk_interval = (time_t) val;
  SL_RETURN(0, _("sh_portchk_set_interval"));
}


static int sh_portchk_set_active   (const char * str)
{
  return sh_util_flagval(str, &sh_portchk_active);
}

static int sh_portchk_set_udp      (const char * str)
{
  return sh_util_flagval(str, &sh_portchk_check_udp);
}

static int sh_portchk_set_severity (const char * str)
{
  char tmp[32];
  tmp[0] = '='; tmp[1] = '\0';
  sl_strlcat (tmp, str, 32);
  return sh_error_set_level (tmp, &sh_portchk_severity);
}

sh_rconf sh_portchk_table[] = {
    {
        N_("severityportcheck"),
        sh_portchk_set_severity,
    },
    {
        N_("portcheckrequired"),
        sh_portchk_add_required,
    },
    {
        N_("portcheckoptional"),
        sh_portchk_add_optional,
    },
    {
        N_("portcheckactive"),
        sh_portchk_set_active,
    },
    {
        N_("portcheckinterface"),
        sh_portchk_add_interface,
    },
    {
        N_("portcheckinterval"),
        sh_portchk_set_interval,
    },
    {
        N_("portcheckudp"),
        sh_portchk_set_udp,
    },
    {
        NULL,
        NULL
    }
};

#endif

/* Interface to initialize port check
 */
int sh_portchk_init ();

/* Interface to reset port check
 */
int sh_portchk_reset ();

/* Interface to run port check
 */
int sh_portchk_check ();


static char * check_services (int port, char * proto);

#ifdef TEST_ONLY

static int portchk_debug = 0;
#define SH_ALLOC       malloc
#define SH_FREE        free
#define sh_util_strdup strdup
#define sl_strlcpy     strncpy
#define _(a)           a

#else

static int portchk_debug = 0;

#endif

static void sh_portchk_add_to_list (char * proto, 
				    int port, struct in_addr haddr, char * service,
				    int flag, int status)
{
  struct sh_portentry * new = SH_ALLOC (sizeof(struct sh_portentry));

  if (portchk_debug)
    fprintf(stderr, _("add to list: port %d/%s %d %d (%s)\n"),
	    port, proto, flag, status, service ? service : _("undef"));

  new->port = port;
  sl_strlcpy (new->interface, inet_ntoa(haddr), SH_INTERFACE_SIZE);
  new->status = status;
  new->flag   = flag;

  new->error  = NULL;

  if (service)
    new->service = sh_util_strdup (service);
  else
    new->service = NULL;
  if (0 == strcmp(proto, "tcp"))
    {
      new->next = portlist_tcp;
      portlist_tcp = new;
    }
  else
    {
      new->next = portlist_udp;
      portlist_udp = new;
    }
  return;
}

/* Reset the list by setting all entries to UNKN.
 * In the next cycle we will check, and set found ports to ISOK.
 * Thereafter, we check for entries that are still UNKN.
 */
static void sh_portchk_reset_lists ()
{
  struct sh_portentry * portlist;

  portlist = portlist_tcp;
  while (portlist)
    {
      if (portlist->status != SH_PORT_MISS)
	portlist->status = SH_PORT_UNKN;
      portlist = portlist->next;
    }
  portlist = portlist_udp;
  while (portlist)
    {
      if (portlist->status != SH_PORT_MISS)
	portlist->status = SH_PORT_UNKN;
      portlist = portlist->next;
    }
  return;
}

static struct sh_portentry * sh_portchk_kill_list (struct sh_portentry * head)
{
  if (head)
    {
      if (head->next)
	sh_portchk_kill_list (head->next);

      if (head->service)
	SH_FREE(head->service);
      SH_FREE(head);
    }
  return NULL;
}
  
/* check the list of open ports for any that are marked as UNKN
 */
static void sh_portchk_check_list (struct sh_portentry ** head, char * proto, int report)
{
  struct sh_portentry * ptr = *head;
  struct sh_portentry * pre = *head;
  char errbuf[256];

  while (ptr)
    {
      if (portchk_debug && report)
	fprintf(stderr, _("check list: port %d/%s %d %d\n"),
		ptr->port, proto, ptr->flag, ptr->status);

      if (ptr->status == SH_PORT_UNKN)
	{
	  /* Don't report missing ports that are marked as optional
	   */
	  if (ptr->flag != SH_PORT_OPT)
	    {
	      snprintf (errbuf, sizeof(errbuf), _("POLICY [ServiceMissing] port %s:%d/%s (%s)"), 
			ptr->interface, ptr->port, proto, 
			ptr->service ? ptr->service : check_services(ptr->port, proto));
#ifdef TEST_ONLY
	      if (report == SH_PORT_REPORT)
		fprintf(stderr, _("%s\n"), errbuf);
#else
	      if (report == SH_PORT_REPORT)
		sh_error_handle(sh_portchk_severity, FIL__, __LINE__, 0, 
				MSG_PORT_REPORT, errbuf);
#endif
	    }

	  ptr->status = SH_PORT_MISS;

	  if ((ptr->flag != SH_PORT_REQ) && (ptr->flag != SH_PORT_OPT))
	    {
	      if (portchk_debug && report)
		fprintf(stderr, _("removing: port %d/%s %d %d\n"),
			ptr->port, proto, ptr->flag, ptr->status);
	      
	      if (ptr == *head)
		{
		  *head = ptr->next;
		  if (ptr->service)
		    SH_FREE(ptr->service);
		  SH_FREE(ptr);
		  ptr = *head;
		  pre = *head;
		  continue;
		}
	      else if (ptr->next == NULL)
		{
		  pre->next = NULL;
		  if (ptr->service)
		    SH_FREE(ptr->service);
		  SH_FREE(ptr);
		  return;
		}
	      else
		{
		  pre->next = ptr->next;
		  if (ptr->service)
		    SH_FREE(ptr->service);
		  SH_FREE(ptr);
		  ptr = pre->next;
		  continue;
		}
	    }
	}
      pre = ptr;
      ptr = ptr->next;
    }
  return;
}


static struct sh_portentry * sh_portchk_get_from_list (char * proto, int port, 
						       struct in_addr haddr, char * service)
{
  struct sh_portentry * portlist;
  char iface_all[8];

  sl_strlcpy (iface_all, _("0.0.0.0"), sizeof(iface_all));
  
  if (0 == strcmp(proto, "tcp"))
    portlist = portlist_tcp;
  else
    portlist = portlist_udp;

  if (service)
    {
      while (portlist) 
	{
	  if (portlist->service && 
	      0 == strcmp(service, portlist->service) &&
	      (0 == strcmp(portlist->interface, inet_ntoa(haddr)) ||
	       0 == strcmp(portlist->interface, iface_all)))
	    return portlist;
	  portlist = portlist->next;
	}
    }
  else
    {
      while (portlist) 
	{
	  if (port == portlist->port &&
	      (0 == strcmp(portlist->interface, inet_ntoa(haddr)) ||
	       0 == strcmp(portlist->interface, iface_all)))
	    return portlist;
	  portlist = portlist->next;
	}
    }
  return NULL;
}
      

static void sh_portchk_cmp_to_list (char * proto, int port, struct in_addr haddr, char * service)
{
  struct sh_portentry * portent;
  char errbuf[256];

  
  portent = sh_portchk_get_from_list (proto, port, haddr, service);

  if (service)
    {
      if (!portent)
	{
	  snprintf (errbuf, sizeof(errbuf), _("POLICY [ServiceNew] port %s:%d/%s (%s)"), 
		    inet_ntoa(haddr), port, proto, service);
#ifdef TEST_ONLY
	  fprintf(stderr, _("open port: %s:%d/%s (%s)\n"), 
		  inet_ntoa(haddr), port, proto, service);
#else
	  sh_error_handle(sh_portchk_severity, FIL__, __LINE__, 0, 
			  MSG_PORT_REPORT, errbuf);
#endif
	  /* 
	   * was not there, thus it is not in 'required' or 'optional' list
	   */
	  sh_portchk_add_to_list (proto, port, haddr, service, SH_PORT_NOT, SH_PORT_ISOK);
	}
      else if (portent->status == SH_PORT_MISS)
	{
	  snprintf (errbuf, sizeof(errbuf), _("POLICY [ServiceRestarted] port %s:%d/%s to %d/%s (%s)"), 
		    inet_ntoa(haddr), portent->port, proto, port, proto, service);
#ifdef TEST_ONLY
	  fprintf(stderr, _("service: %s\n"), errbuf);
#else
	  sh_error_handle(sh_portchk_severity, FIL__, __LINE__, 0, 
			  MSG_PORT_REPORT, errbuf);
#endif

	  portent->status = SH_PORT_ISOK;
	}
      else if (port != portent->port && (-1) != portent->port)
	{
	  snprintf (errbuf, sizeof(errbuf), _("POLICY [ServicePortSwitch] port %s:%d/%s to %d/%s (%s)"), 
		    inet_ntoa(haddr), portent->port, proto, port, proto, service);
#ifdef TEST_ONLY
	  fprintf(stderr, _("service: %s\n"), errbuf);
#else
	  sh_error_handle(sh_portchk_severity, FIL__, __LINE__, 0, 
			  MSG_PORT_REPORT, errbuf);
#endif

	  portent->status = SH_PORT_ISOK;
	}
      else
	{
	  portent->status = SH_PORT_ISOK;
	}
    }
  else
    {
      if (!portent)
	{
	  snprintf (errbuf, sizeof(errbuf), _("POLICY [ServiceNew] port %s:%d/%s (%s)"), 
		    inet_ntoa(haddr), port, proto, check_services(port, proto));
#ifdef TEST_ONLY
	  fprintf(stderr, _("open port: %s:%d/%s (%s)\n"), 
		  inet_ntoa(haddr), port, proto, check_services(port, proto));
#else
	  sh_error_handle(sh_portchk_severity, FIL__, __LINE__, 0, 
			  MSG_PORT_REPORT, errbuf);
#endif

	  /* was not there, thus it is not in 'required' or 'optional' list
	   */
	  sh_portchk_add_to_list (proto, port, haddr, service, SH_PORT_NOT, SH_PORT_ISOK);
	}
      else if (portent->status == SH_PORT_MISS)
	{
	  snprintf (errbuf, sizeof(errbuf), _("POLICY [ServiceRestarted] port %s:%d/%s (%s)"), 
		    inet_ntoa(haddr), port, proto, check_services(port, proto));
#ifdef TEST_ONLY
	  fprintf(stderr, _("port   : %s\n"), errbuf);
#else
	  sh_error_handle(sh_portchk_severity, FIL__, __LINE__, 0, 
			  MSG_PORT_REPORT, errbuf);
#endif

	  portent->status = SH_PORT_ISOK;
	}
      else
	{
	  portent->status = SH_PORT_ISOK;
	}
    }

  return;
}

			       
/* Returns a static buffer containing the name of the service
 * running on port <port> (from /etc/services)
 * Returns NULL on failure
 */
static char * check_services (int port, char * proto)
{
  static char buf[256];
  struct servent * service = getservbyport(htons(port), proto);

  if (service && service->s_name && service->s_name[0] != '\0')
    {
      snprintf (buf, sizeof(buf), _("maybe_%s"), service->s_name);
    }
  else
    {
      snprintf (buf, sizeof(buf), _("unknown"));
    }
  return buf;
}

/* Returns a static buffer containing the name of the service
 * running on port <port> at <address> (from portmap daemon)
 * Returns NULL on failure
 */
static char * check_rpc_list (int port, struct sockaddr_in * address, 
			      unsigned long prot)
{
  struct pmaplist * head;
  struct rpcent *r;
  static char buf[256];

  head = pmap_getmaps(address);

  if (head) 
    {
      do /* while (head != NULL) */
	{
	  if ((head->pml_map.pm_prot == prot) && 
	      (port == (int)head->pml_map.pm_port)) 
	    {
	      r = getrpcbynumber((int)head->pml_map.pm_prog);
	      if (r && r->r_name && r->r_name[0] != '\0')
		{
		  snprintf (buf, sizeof(buf), "%s", r->r_name);
		  return buf;
		}
	      else
		{
		  snprintf (buf, sizeof(buf), "RPC_%lu",
			    (unsigned long)head->pml_map.pm_prog);
		  return buf;
		}
	    }
	  head = head->pml_next;
	}
      while (head != NULL);
    }

  return NULL;
}

static int check_port_udp_internal (int fd, int port, struct in_addr haddr)
{
  struct sockaddr_in sinr;
  /* struct in_addr     haddr; */
  int                retval;
  char             * p;
  char               buf[8];
#ifndef TEST_ONLY
  char               errmsg[256];
  int                nerr;
#endif

  /* inet_aton(interface, &haddr); */

  sinr.sin_family = AF_INET;
  sinr.sin_port   = htons (port);
  sinr.sin_addr   = haddr;

  do {
    retval = connect(fd, (struct sockaddr *) &sinr, sizeof(sinr));
  } while (retval < 0 && errno == EINTR);

  if (retval == -1)
    {
#ifdef TEST_ONLY
      if (portchk_debug)
	perror(_("connect"));
#else
      nerr = errno;
      sl_snprintf(errmsg, sizeof(errmsg), _("check port: %5d/udp on %15s: %s"),
		  port, inet_ntoa(haddr), sh_error_message(errno));
      sh_error_handle((-1), FIL__, __LINE__, nerr, MSG_E_SUBGEN, 
		      errmsg, _("connect"));
#endif
    }
  else
    {
      do {
	retval = send (fd, buf, 0, 0);
      } while (retval < 0 && errno == EINTR);

      if (retval == -1 && errno == ECONNREFUSED)
	{
	  if (portchk_debug)
	    fprintf(stderr, _("check port: %5d/udp on %15s established/time_wait\n"),
		    port, inet_ntoa(haddr));
	}
      else 
	{
	  /* Only the second send() may catch the error 
	   */
	  do {
	    retval = send (fd, buf, 0, 0);
	  } while (retval < 0 && errno == EINTR);

	  if (retval == -1 && errno == ECONNREFUSED)
	    {
	      if (portchk_debug)
		fprintf(stderr, _("check port: %5d/udp on %15s established/time_wait\n"),
			port, inet_ntoa(haddr));
	    }
	  else if (retval != -1)
	    {
	      /* Try to get service name from portmap
	       */
	      p = check_rpc_list (port, &sinr, IPPROTO_UDP);
	      
	      sh_portchk_cmp_to_list ("udp", port, haddr, p ? p : NULL);
	      
	      /* If not an RPC service, try to get name from /etc/services
	       */
	      if (!p)
		p = check_services(port, "udp");
	      
	      if (portchk_debug)
		fprintf(stderr, _("check port: %5d/udp on %15s open %s\n"), 
			port, inet_ntoa(haddr), p);
	      
	    }
	}
    }
  close (fd);
  return 0;
}

static int check_port_tcp_internal (int fd, int port, struct in_addr haddr)
{
  struct sockaddr_in sinr;
  /* struct in_addr     haddr; */
  int                retval;
  char             * p;
#ifndef TEST_ONLY
  char               errmsg[256];
  int                nerr;
#endif


  /* inet_aton(interface, &haddr); */

  sinr.sin_family = AF_INET;
  sinr.sin_port   = htons (port);
  sinr.sin_addr   = haddr;

  do {
    retval = connect(fd, (struct sockaddr *) &sinr, sizeof(sinr));
  } while (retval < 0 && errno == EINTR);

  if (retval == -1 && errno == ECONNREFUSED)
    {
      if (portchk_debug)
	fprintf(stderr, _("check port: %5d on %15s established/time_wait\n"),
		port, inet_ntoa(haddr));
    }
  else if (retval == -1)
    {
#ifdef TEST_ONLY
      if (portchk_debug)
	perror(_("connect"));
#else
      nerr = errno;
      sl_snprintf(errmsg, sizeof(errmsg), _("check port: %5d/tcp on %15s: %s"),
		  port, inet_ntoa(haddr), sh_error_message(errno));
      sh_error_handle((-1), FIL__, __LINE__, nerr, MSG_E_SUBGEN, 
		      errmsg, _("connect"));
#endif
    }
  else
    {
      /* Try to get service name from portmap
       */
      p = check_rpc_list (port, &sinr, IPPROTO_TCP);

      sh_portchk_cmp_to_list ("tcp", port, haddr, p ? p : NULL);

      /* If not an RPC service, try to get name from /etc/services
       */
      if (!p)
	p = check_services(port, "tcp");

      if (portchk_debug)
	fprintf(stderr, _("check port: %5d on %15s open %s\n"), 
		port, inet_ntoa(haddr), p);
     }
  close (fd);
  return 0;
}

/* typedef uint32_t in_addr_t;
 * struct in_addr
 * {
 * in_addr_t s_addr;
 * };
 */

#define SH_IFACE_MAX 16

struct portchk_interfaces {
  struct in_addr iface[SH_IFACE_MAX];
  int            used;
};

static struct portchk_interfaces iface_list;
static int iface_initialized = 0;

#ifdef TEST_ONLY
static char * portchk_hostname = NULL;
#else
static char * portchk_hostname = sh.host.name;
#endif

int sh_portchk_init ()
{
  struct hostent * hent;
  int              i = 0;
  char errbuf[256];

  if (portchk_debug)
    fprintf(stderr, _("checking ports on: %s\n"), portchk_hostname ? portchk_hostname : _("NULL"));

  if (!portchk_hostname)
    return -1;

  if (sh_portchk_active == S_FALSE)
    return -1;

  if (iface_initialized == 0)
    {
      iface_list.used   = 0;
      iface_initialized = 1;
    }
	    
  hent = gethostbyname(portchk_hostname);

  while (hent && hent->h_addr_list[i] && (iface_list.used < SH_IFACE_MAX))
    {
      memcpy (&(iface_list.iface[iface_list.used].s_addr), hent->h_addr_list[i], sizeof(in_addr_t));
      sl_snprintf(errbuf, sizeof(errbuf), _("interface: %s"), 
		  inet_ntoa(iface_list.iface[iface_list.used]));
      sh_error_handle(SH_ERR_INFO, FIL__, __LINE__, 0, MSG_E_SUBGEN, 
		      errbuf, _("sh_portchk_init"));

      ++iface_list.used;
      ++i;
    }

  return 0;
}

#if !defined(TEST_ONLY)
int sh_portchk_reconf ()
{
  iface_initialized    = 0;

  sh_portchk_active    = 1;
  sh_portchk_check_udp = 1;

  portlist_udp = sh_portchk_kill_list (portlist_udp);
  portlist_tcp = sh_portchk_kill_list (portlist_tcp);
  return 0;
}

int sh_portchk_cleanup ()
{
  return sh_portchk_reconf ();
}

int sh_portchk_timer (time_t tcurrent) 
{
  static time_t lastcheck = 0;

  SL_ENTER(_("sh_portchk_timer"));
  if ((time_t) (tcurrent - lastcheck) >= sh_portchk_interval)
    {
      lastcheck  = tcurrent;
      SL_RETURN((-1), _("sh_portchk_timer"));
    }
  SL_RETURN(0, _("sh_portchk_timer"));
}
#endif

static int check_port_generic (int port, int type, int protocol)
{
  int              i    =  0;
  int              sock = -1;
  int              flag =  1; /* non-zero to enable an option */
  struct in_addr   haddr;
 
  /* Check all interfaces for this host
   */
  while (i < iface_list.used)
    {
      if ((sock = socket(AF_INET, type, protocol)) < 0 )
	{
#ifdef TEST_ONLY
	  if (portchk_debug)
	    perror(_("socket"));
#else
	  sh_error_handle((-1), FIL__, __LINE__, errno, MSG_E_SUBGEN, 
			  sh_error_message(errno), _("socket"));
#endif
	}
      if ( setsockopt(sock, SOL_SOCKET, SO_REUSEADDR,
		      (void *) &flag, sizeof(flag)) < 0 )
	{
#ifdef TEST_ONLY
	  if (portchk_debug)
	    perror(_("setsockopt"));
#else
	  sh_error_handle((-1), FIL__, __LINE__, errno, MSG_E_SUBGEN, 
			  sh_error_message(errno), _("setsockopt"));
#endif
	}

      memcpy (&(haddr.s_addr), &(iface_list.iface[i].s_addr), sizeof(in_addr_t));

      if (protocol == IPPROTO_TCP)
	check_port_tcp_internal(sock, port, haddr);
      else
	check_port_udp_internal(sock, port, haddr);

      ++i;
    }

  return 0;
}



static int check_port_udp (int port)
{
  return check_port_generic(port, SOCK_DGRAM, IPPROTO_UDP);
}

static int check_port_tcp (int port)
{
  return check_port_generic(port, SOCK_STREAM, IPPROTO_TCP);
}



static int sh_portchk_scan_ports_generic (int min_port, int max_port, int type, int protocol)
{
  /*
  int min_port = 1024;
  int max_port = 65535;
  */

  int port;
  int retval;
  int sock   = -1;
  int flag   = 1; /* non-zero to enable an option */

  struct sockaddr_in addr;
  int addrlen      = sizeof(addr);

  if (min_port == -1)
     min_port = 0;
  if (max_port == -1)
    max_port = 65535;

  for (port = min_port; port <= max_port; ++port) 
    {

      if ((sock = socket(AF_INET, type, protocol)) < 0 )
	{
#ifdef TEST_ONLY
	  if (portchk_debug)
	    perror(_("socket"));
#else
	  sh_error_handle((-1), FIL__, __LINE__, errno, MSG_E_SUBGEN, 
			  sh_error_message(errno), _("socket"));
#endif
	}
      if ( setsockopt(sock, SOL_SOCKET, SO_REUSEADDR,
		      (void *) &flag, sizeof(flag)) < 0 )
	{
#ifdef TEST_ONLY
	  if (portchk_debug)
	    perror(_("setsockopt"));
#else
	  sh_error_handle((-1), FIL__, __LINE__, errno, MSG_E_SUBGEN, 
			  sh_error_message(errno), _("setsockopt"));
#endif
	}

      addr.sin_family      = AF_INET;
      addr.sin_port        = htons(port);
      addr.sin_addr.s_addr = INADDR_ANY;

      retval = bind (sock, (struct sockaddr *) &addr, addrlen);

      if (retval == 0)
	{
	  /* we can bind the port, thus it is unused
	   */
	  close (sock);
	}
      else
	{
	  if (errno == EINVAL || errno == EADDRINUSE)
	    {
	      /* try to connect to the port
	       */
	      if (protocol == IPPROTO_TCP)
		check_port_tcp(port);
	      else
		check_port_udp(port);
	    }
	  else
	    {
#ifdef TEST_ONLY
	      if (portchk_debug)
		perror(_("bind"));
#else
	      sh_error_handle((-1), FIL__, __LINE__, errno, MSG_E_SUBGEN, 
			      sh_error_message(errno), _("bind"));
#endif
	    }
	  close (sock);
	}
    }
  return 0;
}

static int sh_portchk_scan_ports_tcp (int min_port, int max_port)
{
  return sh_portchk_scan_ports_generic (min_port, max_port, SOCK_STREAM, IPPROTO_TCP);
}
 
static int sh_portchk_scan_ports_udp (int min_port, int max_port)
{
  return sh_portchk_scan_ports_generic (min_port, max_port, SOCK_DGRAM, IPPROTO_UDP);
}

/* Subroutine to add an interface
 */
static int sh_portchk_add_interface (const char * str)
{
  struct in_addr   haddr;
  char errbuf[256];

  if (iface_initialized == 0)
    {
      iface_list.used   = 0;
      iface_initialized = 1;
    }

  if (0 == inet_aton(str, &haddr))
    return -1;

  if (iface_list.used == SH_IFACE_MAX)
    return -1;

  sl_snprintf(errbuf, sizeof(errbuf), _("interface: %s"), inet_ntoa(haddr));
  sh_error_handle(SH_ERR_INFO, FIL__, __LINE__, 0, MSG_E_SUBGEN, 
		  errbuf, _("sh_portchk_add_interface"));

  memcpy (&(iface_list.iface[iface_list.used].s_addr), &(haddr.s_addr), sizeof(in_addr_t));
  ++iface_list.used;

  return 0;
}

 
/* Subroutine to add a required or optional port/service
 */
static int sh_portchk_add_required_port_generic (char * service, char * interface, int type)
{
  char buf[256];
  char proto[4];
  char * p;
  char * endptr;
  unsigned long int  port;
  struct in_addr   haddr;
  struct sh_portentry * portent;

  if (0 == inet_aton(interface, &haddr))
    return -1;

  sl_strlcpy (buf, service, sizeof(buf));

  p = strchr(buf, '/');
  if (!p)
    return -1;
  if (0 == strcmp(p, _("/tcp")))
    sl_strlcpy(proto, _("tcp"), sizeof(proto));
  else if  (0 == strcmp(p, _("/udp")))   
    sl_strlcpy(proto, _("udp"), sizeof(proto));
  else
    return -1;

  *p = '\0';
  port = strtoul(buf, &endptr, 0);

  if (*endptr != '\0')
    {  
      portent = sh_portchk_get_from_list (proto, -1, haddr, buf);
      if (!portent)
	sh_portchk_add_to_list (proto,   -1, haddr,  buf, type, SH_PORT_UNKN);
      else
	{
#ifdef TEST_ONLY
	  fprintf(stderr, "** WARNING: duplicate port definition %s/%s\n", buf, proto);
#else
	  sh_error_handle(SH_ERR_ERR, FIL__, __LINE__, 0, MSG_E_SUBGEN, 
			  _("duplicate port definition"), _("sh_portchk_add_required_port_generic"));
#endif
	  return -1;
	}
    }
  else if (port <= 65535)
    {
      portent = sh_portchk_get_from_list (proto, port, haddr, NULL);
      if (!portent)
	sh_portchk_add_to_list (proto, port, haddr, NULL, type, SH_PORT_UNKN);
      else
	{
#ifdef TEST_ONLY
	  fprintf(stderr, "** WARNING: duplicate port definition %lu/%s\n", port, proto);
#else
	  sh_error_handle(SH_ERR_ERR, FIL__, __LINE__, 0, MSG_E_SUBGEN, 
			  _("duplicate port definition"), _("sh_portchk_add_required_port_generic"));
#endif
	  return -1;
	}
    }
  else
    return -1;

  return 0;
}

/* Internal interface to add required or optional ports as 'iface:portlist'
 */
static int sh_portchk_add_required_generic (const char * str, int type)
{
  size_t len;
  size_t ll = 0;

  char * interface = NULL;
  char * list;
  char * p;

  if (!str)
    return -1;

  if (strchr(str, ':'))
    {
      len = strlen(str);
      for (ll = 0; ll < len; ++ll)
	{
	  if (str[ll] == ':' || str[ll] == ' ' || str[ll] == '\t')
	    {
	      interface = SH_ALLOC(ll+1);
	      sl_strlcpy(interface, str, ll+1);
	      interface[ll] = '\0';
	      while (str[ll] == ':' || str[ll] == ' ' || str[ll] == '\t')
		++ll;
	      break;
	    }
	}
    }
  else
    {
      interface = SH_ALLOC(8);
      sl_strlcpy(interface, _("0.0.0.0"), 8);
      interface[7] = '\0';
      while (str[ll] == ' ' || str[ll] == '\t')
	++ll;      
    }

  if (!interface)
    return -1;

  if (str[ll] == '\0')
    {
      SH_FREE(interface);
      return -1;
    }

  if (portchk_debug)
    fprintf(stderr, "add ports for interface: %s\n", interface);

  list = sh_util_strdup(&str[ll]);
  p    = strtok (list, " ,\t");
  if (!p)
    {
      SH_FREE(interface);
      SH_FREE(list);
      return -1;
    }
  while (p)
    {
      if (-1 == sh_portchk_add_required_port_generic (p, interface, type))
	{
	  SH_FREE(interface);
	  SH_FREE(list);
	  return -1;
	}
      p    = strtok (NULL, " ,\t");
    }
  SH_FREE(interface);
  SH_FREE(list);
  return 0;
}

/* User interface to add required ports as 'iface:portlist'
 */
static int sh_portchk_add_required (const char * str)
{
  return sh_portchk_add_required_generic (str, SH_PORT_REQ); 
}

/* User interface to add optional ports as 'iface:portlist'
 */
static int sh_portchk_add_optional (const char * str)
{
  return sh_portchk_add_required_generic (str, SH_PORT_OPT); 
}

/* Interface to run port check
 */
int sh_portchk_check ()
{
  int min_port = 0;

  if (sh_portchk_active != S_FALSE)
    {
      sh_portchk_reset_lists();
      if (0 != geteuid())
	{
	  min_port = 1024;
#ifdef TEST_ONLY
	  fprintf(stderr, "** WARNING not scanning ports < 1024\n");
#else
	  sh_error_handle(SH_ERR_ERR, FIL__, __LINE__, 0, MSG_E_SUBGEN, 
			  _("not scanning ports below 1024"), _("sh_portchk_check"));
#endif
	}
      if (sh_portchk_check_udp == 1)
	sh_portchk_scan_ports_udp(min_port, -1);
      sh_portchk_scan_ports_tcp(min_port, -1);
      sh_portchk_check_list (&portlist_tcp, "tcp", SH_PORT_REPORT);
      if (sh_portchk_check_udp == 1)
	sh_portchk_check_list (&portlist_udp, "udp", SH_PORT_REPORT);
    }
  return 0;
}
#endif

#ifdef SH_CUTEST
#include "CuTest.h"

void Test_portcheck_lists (CuTest *tc)
{
#if defined(SH_USE_PORTCHECK) && (defined(SH_WITH_CLIENT) || defined(SH_STANDALONE))
  struct in_addr   haddr_local;
  struct sh_portentry * portent;

  CuAssertTrue(tc, 0 != inet_aton("127.0.0.1", &haddr_local));

  sh_portchk_add_to_list ("tcp",  8000, haddr_local, NULL, SH_PORT_NOT, SH_PORT_UNKN);

  portent = sh_portchk_get_from_list("tcp",  8000, haddr_local, NULL);
  CuAssertPtrNotNull(tc, portent);

  CuAssertTrue(tc, portent->port == 8000);
  CuAssertTrue(tc, 0 == strcmp("127.0.0.1", portent->interface));
  CuAssertTrue(tc, portent->status == SH_PORT_UNKN);
  CuAssertTrue(tc, portent->flag == SH_PORT_NOT);

  sh_portchk_check_list (&portlist_tcp, "tcp", SH_PORT_NOREPT);

  CuAssertTrue(tc, NULL == portlist_tcp);

  sh_portchk_add_to_list ("tcp",  8000, haddr_local, NULL, SH_PORT_REQ, SH_PORT_UNKN);
  sh_portchk_add_to_list ("tcp",  8001, haddr_local, NULL, SH_PORT_NOT, SH_PORT_UNKN);
  sh_portchk_add_to_list ("tcp",  8002, haddr_local, NULL, SH_PORT_REQ, SH_PORT_UNKN);
  sh_portchk_add_to_list ("tcp",  8003, haddr_local, NULL, SH_PORT_NOT, SH_PORT_UNKN);
  sh_portchk_add_to_list ("tcp",    -1, haddr_local, "foo1", SH_PORT_NOT, SH_PORT_UNKN);
  sh_portchk_add_to_list ("tcp",    -1, haddr_local, "foo2", SH_PORT_REQ, SH_PORT_UNKN);
  sh_portchk_add_to_list ("tcp",    -1, haddr_local, "foo3", SH_PORT_NOT, SH_PORT_UNKN);
  sh_portchk_add_to_list ("tcp",    -1, haddr_local, "foo4", SH_PORT_REQ, SH_PORT_UNKN);

  sh_portchk_check_list (&portlist_tcp, "tcp", SH_PORT_NOREPT);

  CuAssertPtrNotNull(tc, portlist_tcp);

  portent = sh_portchk_get_from_list("tcp",  8000, haddr_local, NULL);
  CuAssertPtrNotNull(tc, portent);

  portent = sh_portchk_get_from_list("tcp",  8001, haddr_local, NULL);
  CuAssertTrue(tc, NULL == portent);

  portent = sh_portchk_get_from_list("tcp",  8002, haddr_local, NULL);
  CuAssertPtrNotNull(tc, portent);

  portent = sh_portchk_get_from_list("tcp",  8003, haddr_local, NULL);
  CuAssertTrue(tc, NULL == portent);

  portent = sh_portchk_get_from_list("tcp",  8000, haddr_local, "foo1");
  CuAssertTrue(tc, NULL == portent);

  portent = sh_portchk_get_from_list("tcp",  8000, haddr_local, "foo2");
  CuAssertPtrNotNull(tc, portent);
  CuAssertTrue(tc, 0 == strcmp(portent->service, "foo2"));

  portent = sh_portchk_get_from_list("tcp",  8000, haddr_local, "foo3");
  CuAssertTrue(tc, NULL == portent);

  portent = sh_portchk_get_from_list("tcp",  8000, haddr_local, "foo4");
  CuAssertPtrNotNull(tc, portent);
  CuAssertTrue(tc, 0 == strcmp(portent->service, "foo4"));
#else
  (void) tc; /* fix compiler warning */
#endif
  return;
}
#endif

#ifdef TEST_ONLY

void usage (char * pname)
{
  printf ("%s [-r|--required interface:portlist][-o|--optional interface:portlist][--no-udp][-d|--debug] hostname\n\n", pname);
  printf ("   Check local host for open ports; Version %s\n\n", PORTCHK_VERSION);
  printf ("   Interface: Numeric address for an interface, e.g. 127.0.0.1\n");
  printf ("   Portlist:  List of ports or services, e.g. 22/tcp,nfs/udp,nlockmgr/udp\n");
  printf ("     required -> must be open\n");
  printf ("     optional ->  may be open or closed\n");
  printf ("   RPC services must be specified with service **name**, others with **port number**\n\n");
  printf ("   Example:\n");
  printf ("      %s --required 192.168.1.2:22/tcp,nfs/udp,nlockmgr/udp\n\n", pname);
  return;
}

int main(int argc, char *argv[])
{
  char * pname = argv[0];


  /* 
  test_lists();

  portlist_tcp = sh_portchk_kill_list (portlist_tcp);
  portlist_udp = sh_portchk_kill_list (portlist_udp);
  */

  // sh_portchk_add_required ("127.0.0.1 : nlockmgr/tcp, 5308/tcp, nfs/tcp");

  while (argc > 1 && argv[1][0] == '-')
    {
      if (0 == strcmp(argv[1], "--help") || 0 == strcmp(argv[1], "-h"))
	{
	  usage(pname);
	  exit (0);
	}
      else if (0 == strcmp(argv[1], "--required") || 0 == strcmp(argv[1], "-r"))
	{
	  if (argc < 3)
	    {
	      usage(pname);
	      exit (1);
	    }
	  sh_portchk_add_required (argv[2]);
	  --argc; ++argv;
	}
      else if (0 == strcmp(argv[1], "--optional") || 0 == strcmp(argv[1], "-o"))
	{
	  if (argc < 3)
	    {
	      usage(pname);
	      exit (1);
	    }
	  sh_portchk_add_optional (argv[2]);
	  --argc; ++argv;
	}
      else if (0 == strcmp(argv[1], "--no-udp"))
	{
	  sh_portchk_check_udp = 0;
	}
      else if (0 == strcmp(argv[1], "--debug") || 0 == strcmp(argv[1], "-d"))
	{
	  portchk_debug = 1;
	}
      else
	{
	  usage(pname);
	  exit (1);
	}
      --argc; ++argv;
    }

  if (argc < 2)
    {
      usage(pname);
      exit (1);
    }

  portchk_hostname = argv[1];
      
  if (0 != sh_portchk_init ())
    {
      usage(pname);
      exit (1);
    }

  sh_portchk_check();

  /*
  sleep(10);

  sh_portchk_check();
  */

  return 0;
}
#endif
