text: /*	$NetBSD: bindresvport.c,v 1.19 2000/07/06 03:03:59 christos Exp $	*/
  
  /*-
   * SPDX-License-Identifier: BSD-3-Clause
   *
   * Copyright (c) 2009, Sun Microsystems, Inc.
   * All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without 
   * modification, are permitted provided that the following conditions are met:
   * - Redistributions of source code must retain the above copyright notice, 
   *   this list of conditions and the following disclaimer.
   * - Redistributions in binary form must reproduce the above copyright notice, 
   *   this list of conditions and the following disclaimer in the documentation 
   *   and/or other materials provided with the distribution.
   * - Neither the name of Sun Microsystems, Inc. nor the names of its 
   *   contributors may be used to endorse or promote products derived 
   *   from this software without specific prior written permission.
   * 
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 
   * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 
   * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE 
   * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 
   * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 
   * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
   * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
   * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 
   * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 
   * POSSIBILITY OF SUCH DAMAGE.
   */
  
  #if defined(LIBC_SCCS) && !defined(lint)
  static char *sccsid2 = "from: @(#)bindresvport.c 1.8 88/02/08 SMI";
  static char *sccsid = "from: @(#)bindresvport.c	2.2 88/07/29 4.0 RPCSRC";
  #endif
  /* from: $OpenBSD: bindresvport.c,v 1.7 1996/07/30 16:25:47 downsj Exp $ */
  #include <sys/cdefs.h>
  __FBSDID("$FreeBSD$");
  
  /*
   * Copyright (c) 1987 by Sun Microsystems, Inc.
   *
   * Portions Copyright(C) 1996, Jason Downs.  All rights reserved.
   */
  
  #include "namespace.h"
  #include <sys/types.h>
  #include <sys/socket.h>
  
  #include <netinet/in.h>
  
  #include <errno.h>
  #include <string.h>
  #include <unistd.h>
  
  #include <rpc/rpc.h>
  
  #include <string.h>
  #include "un-namespace.h"
  
  /*
   * Bind a socket to a privileged IP port
   */
  int
  bindresvport(int sd, struct sockaddr_in *sin)
  {
  	return bindresvport_sa(sd, (struct sockaddr *)sin);
  }
  
  /*
   * Bind a socket to a privileged IP port
   */
  int
  bindresvport_sa(int sd, struct sockaddr *sa)
  {
  	int old, error, af;
  	struct sockaddr_storage myaddr;
  	struct sockaddr_in *sin;
  #ifdef INET6
  	struct sockaddr_in6 *sin6;
  #endif
  	int proto, portrange, portlow;
  	u_int16_t *portp;
  	socklen_t salen;
  
  	if (sa == NULL) {
  		salen = sizeof(myaddr);
  		sa = (struct sockaddr *)&myaddr;
  
  		if (_getsockname(sd, sa, &salen) == -1)
  			return -1;	/* errno is correctly set */
  
  		af = sa->sa_family;
  		memset(sa, 0, salen);
  	} else
  		af = sa->sa_family;
  
  	switch (af) {
  	case AF_INET:
  		proto = IPPROTO_IP;
  		portrange = IP_PORTRANGE;
  		portlow = IP_PORTRANGE_LOW;
  		sin = (struct sockaddr_in *)sa;
  		salen = sizeof(struct sockaddr_in);
  		portp = &sin->sin_port;
  		break;
  #ifdef INET6
  	case AF_INET6:
  		proto = IPPROTO_IPV6;
  		portrange = IPV6_PORTRANGE;
  		portlow = IPV6_PORTRANGE_LOW;
  		sin6 = (struct sockaddr_in6 *)sa;
  		salen = sizeof(struct sockaddr_in6);
  		portp = &sin6->sin6_port;
  		break;
  #endif
  	default:
  		errno = EPFNOSUPPORT;
  		return (-1);
  	}
  	sa->sa_family = af;
  	sa->sa_len = salen;
  
  	if (*portp == 0) {
  		socklen_t oldlen = sizeof(old);
  
  		error = _getsockopt(sd, proto, portrange, &old, &oldlen);
  		if (error < 0)
  			return (error);
  
  		error = _setsockopt(sd, proto, portrange, &portlow,
  		    sizeof(portlow));
  		if (error < 0)
  			return (error);
  	}
  
  	error = _bind(sd, sa, salen);
  
  	if (*portp == 0) {
  		int saved_errno = errno;
  
  		if (error < 0) {
  			if (_setsockopt(sd, proto, portrange, &old,
  			    sizeof(old)) < 0)
  				errno = saved_errno;
  			return (error);
  		}
  
  		if (sa != (struct sockaddr *)&myaddr) {
  			/* Hmm, what did the kernel assign? */
  			if (_getsockname(sd, sa, &salen) < 0)
  				errno = saved_errno;
  			return (error);
  		}
  	}
  	return (error);
  }
  