openssh/bsd-bindresvport.c
Damien Miller b9b94a74e6 - Clean up bsd-bindresvport.c. Use arc4random() for picking initial
port, ignore EINVAL errors (Linux) when searching for free port.
2000-01-17 09:52:46 +11:00

107 lines
2.8 KiB
C

/*
* Sun RPC is a product of Sun Microsystems, Inc. and is provided for
* unrestricted use provided that this legend is included on all tape
* media and as a part of the software program in whole or part. Users
* may copy or modify Sun RPC without charge, but are not authorized
* to license or distribute it to anyone else except as part of a product or
* program developed by the user.
*
* SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
* WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
* PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
*
* Sun RPC is provided with no support and without any obligation on the
* part of Sun Microsystems, Inc. to assist in its use, correction,
* modification or enhancement.
*
* SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
* INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
* OR ANY PART THEREOF.
*
* In no event will Sun Microsystems, Inc. be liable for any lost revenue
* or profits or other special, indirect and consequential damages, even if
* Sun has been advised of the possibility of such damages.
*
* Sun Microsystems, Inc.
* 2550 Garcia Avenue
* Mountain View, California 94043
*/
#include "config.h"
#ifndef HAVE_BINRESVPORT_AF
#if defined(LIBC_SCCS) && !defined(lint)
static char *rcsid = "$OpenBSD: bindresvport.c,v 1.11 1999/12/17 19:22:08 deraadt Exp $";
#endif /* LIBC_SCCS and not lint */
/*
* Copyright (c) 1987 by Sun Microsystems, Inc.
*
* Portions Copyright(C) 1996, Jason Downs. All rights reserved.
*/
#include "includes.h"
#define STARTPORT 600
#define ENDPORT (IPPORT_RESERVED - 1)
#define NPORTS (ENDPORT - STARTPORT + 1)
/*
* Bind a socket to a privileged IP port
*/
int
bindresvport_af(sd, sa, af)
int sd;
struct sockaddr *sa;
int af;
{
int error;
struct sockaddr_storage myaddr;
struct sockaddr_in *sin;
struct sockaddr_in6 *sin6;
u_int16_t *portp;
int salen;
int i;
if (sa == NULL) {
memset(&myaddr, 0, sizeof(myaddr));
sa = (struct sockaddr *)&myaddr;
}
if (af == AF_INET) {
sin = (struct sockaddr_in *)sa;
salen = sizeof(struct sockaddr_in);
portp = &sin->sin_port;
} else if (af == AF_INET6) {
sin6 = (struct sockaddr_in6 *)sa;
salen = sizeof(struct sockaddr_in6);
portp = &sin6->sin6_port;
} else {
errno = EPFNOSUPPORT;
return (-1);
}
sa->sa_family = af;
if (*portp == 0)
*portp = (arc4random() % NPORTS) + STARTPORT;
for(i = 0; i < NPORTS; i++) {
error = bind(sd, sa, salen);
/* Terminate on success */
if (error == 0)
break;
/* Terminate on errors, except "address already in use" */
if ((error < 0) && ((errno != EADDRINUSE) || (errno != EINVAL)))
break;
*portp = (i % NPORTS) + STARTPORT;
}
return (error);
}
#endif /* HAVE_BINRESVPORT_AF */