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/* Copyright (C) 2002 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, write to the Free
Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
Boston, MA 0211-1301 USA */
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <netdb.h>
#include <rpc/rpc.h>
#include <sys/socket.h>
#include <sys/fcntl.h>
#include <errno.h>
#ifdef _LIBC
# include <libintl.h>
#else
# ifndef _
# define _(s) (s)
# endif
# define __socket(d, t, p) socket ((d), (t), (p))
# define __close(f) close ((f))
#endif
int getservport(u_long number, const char *proto)
{
char rpcdata[1024], servdata[1024];
struct rpcent rpcbuf, *rpcp;
struct servent servbuf, *servp = NULL;
int ret;
ret = getrpcbynumber_r(number, &rpcbuf, rpcdata, sizeof rpcdata,
&rpcp);
if (ret == 0 && rpcp != NULL) {
/* First try name. */
ret = getservbyname_r(rpcp->r_name, proto, &servbuf, servdata,
sizeof servdata, &servp);
if ((ret != 0 || servp == NULL) && rpcp->r_aliases) {
const char **a;
/* Then we try aliases. */
for (a = (const char **) rpcp->r_aliases; *a != NULL; a++) {
ret = getservbyname_r(*a, proto, &servbuf, servdata,
sizeof servdata, &servp);
if (ret == 0 && servp != NULL)
break;
}
}
}
if (ret == 0 && servp != NULL)
return ntohs(servp->s_port);
return 0;
}
static int
svc_socket (u_long number, int type, int protocol, int reuse)
{
struct sockaddr_in addr;
socklen_t len = sizeof (struct sockaddr_in);
int sock, ret;
const char *proto = protocol == IPPROTO_TCP ? "tcp" : "udp";
if ((sock = __socket (AF_INET, type, protocol)) < 0)
{
perror (_("svc_socket: socket creation problem"));
return sock;
}
if (reuse)
{
ret = 1;
ret = setsockopt (sock, SOL_SOCKET, SO_REUSEADDR, &ret,
sizeof (ret));
if (ret < 0)
{
perror (_("svc_socket: socket reuse problem"));
return ret;
}
}
memset (&addr, 0, sizeof (addr));
addr.sin_family = AF_INET;
addr.sin_port = htons(getservport(number, proto));
if (bind(sock, (struct sockaddr *) &addr, len) < 0)
{
perror (_("svc_socket: bind problem"));
(void) __close(sock);
sock = -1;
}
if (sock >= 0)
{
/* This socket might be shared among multiple processes
* if mountd is run multi-threaded. So it is safest to
* make it non-blocking, else all threads might wake
* one will get the data, and the others will block
* indefinitely.
* In all cases, transaction on this socket are atomic
* (accept for TCP, packet-read and packet-write for UDP)
* so O_NONBLOCK will not confuse unprepared code causing
* it to corrupt messages.
* It generally safest to have O_NONBLOCK when doing an accept
* as if we get a RST after the SYN and before accept runs,
* we can block despite being told there was an acceptable
* connection.
*/
int flags;
if ((flags = fcntl(sock, F_GETFL)) < 0)
{
perror (_("svc_socket: can't get socket flags"));
(void) __close (sock);
sock = -1;
}
else if (fcntl(sock, F_SETFL, flags|O_NONBLOCK) < 0)
{
perror (_("svc_socket: can't set socket flags"));
(void) __close (sock);
sock = -1;
}
}
return sock;
}
/*
* Create and bind a TCP socket based on program number
*/
int
svctcp_socket (u_long number, int reuse)
{
return svc_socket (number, SOCK_STREAM, IPPROTO_TCP, reuse);
}
/*
* Create and bind a UDP socket based on program number
*/
int
svcudp_socket (u_long number)
{
return svc_socket (number, SOCK_DGRAM, IPPROTO_UDP, FALSE);
}
#ifdef TEST
static int
check (u_long number, u_short port, int protocol, int reuse)
{
int socket;
int result;
struct sockaddr_in addr;
socklen_t len = sizeof (struct sockaddr_in);
if (protocol == IPPROTO_TCP)
socket = svctcp_socket (number, reuse);
else
socket = svcudp_socket (number);
if (socket < 0)
return 1;
result = getsockname (socket, (struct sockaddr *) &addr, &len);
if (result == 0)
{
if (port != 0 && ntohs (addr.sin_port) != port)
printf ("Program: %ld, expect port: %d, got: %d\n",
number, port, ntohs (addr.sin_port));
else
printf ("Program: %ld, port: %d\n",
number, ntohs (addr.sin_port));
}
close (socket);
return result;
}
int
main (void)
{
int result = 0;
result += check (100001, 0, IPPROTO_TCP, 0);
result += check (100001, 0, IPPROTO_UDP, 0);
result += check (100003, 2049, IPPROTO_TCP, 1);
result += check (100003, 2049, IPPROTO_UDP, 1);
return result;
}
#endif
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