NetBSD/sys/netinet/udp_usrreq.c
drochner d8f1d9401e Adjust packet len in mbuf header for incoming broadcasts.
Closes PR kern/4087 (by myself).
1997-09-12 10:58:31 +00:00

654 lines
15 KiB
C

/* $NetBSD: udp_usrreq.c,v 1.43 1997/09/12 10:58:31 drochner Exp $ */
/*
* Copyright (c) 1982, 1986, 1988, 1990, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. 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.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University 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 REGENTS 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 REGENTS 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.
*
* @(#)udp_usrreq.c 8.4 (Berkeley) 1/21/94
*/
#include "ipkdb.h"
#include <sys/param.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/protosw.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/errno.h>
#include <sys/stat.h>
#include <sys/systm.h>
#include <sys/proc.h>
#include <vm/vm.h>
#include <sys/sysctl.h>
#include <net/if.h>
#include <net/route.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/in_var.h>
#include <netinet/ip.h>
#include <netinet/in_pcb.h>
#include <netinet/ip_var.h>
#include <netinet/ip_icmp.h>
#include <netinet/udp.h>
#include <netinet/udp_var.h>
#include <machine/stdarg.h>
/*
* UDP protocol implementation.
* Per RFC 768, August, 1980.
*/
#ifndef COMPAT_42
int udpcksum = 1;
#else
int udpcksum = 0; /* XXX */
#endif
static void udp_notify __P((struct inpcb *, int));
#ifndef UDBHASHSIZE
#define UDBHASHSIZE 128
#endif
int udbhashsize = UDBHASHSIZE;
void
udp_init()
{
in_pcbinit(&udbtable, udbhashsize, udbhashsize);
}
void
#if __STDC__
udp_input(struct mbuf *m, ...)
#else
udp_input(m, va_alist)
struct mbuf *m;
va_dcl
#endif
{
register struct ip *ip;
register struct udphdr *uh;
register struct inpcb *inp;
struct mbuf *opts = 0;
int len;
struct ip save_ip;
int iphlen;
va_list ap;
struct sockaddr_in udpsrc;
va_start(ap, m);
iphlen = va_arg(ap, int);
va_end(ap);
udpstat.udps_ipackets++;
/*
* Strip IP options, if any; should skip this,
* make available to user, and use on returned packets,
* but we don't yet have a way to check the checksum
* with options still present.
*/
if (iphlen > sizeof (struct ip)) {
ip_stripoptions(m, (struct mbuf *)0);
iphlen = sizeof(struct ip);
}
/*
* Get IP and UDP header together in first mbuf.
*/
ip = mtod(m, struct ip *);
if (m->m_len < iphlen + sizeof(struct udphdr)) {
if ((m = m_pullup(m, iphlen + sizeof(struct udphdr))) == 0) {
udpstat.udps_hdrops++;
return;
}
ip = mtod(m, struct ip *);
}
uh = (struct udphdr *)((caddr_t)ip + iphlen);
/*
* Make mbuf data length reflect UDP length.
* If not enough data to reflect UDP length, drop.
*/
len = ntohs((u_int16_t)uh->uh_ulen);
if (ip->ip_len != len) {
if (len > ip->ip_len) {
udpstat.udps_badlen++;
goto bad;
}
m_adj(m, len - ip->ip_len);
/* ip->ip_len = len; */
}
/*
* Save a copy of the IP header in case we want restore it
* for sending an ICMP error message in response.
*/
save_ip = *ip;
/*
* Checksum extended UDP header and data.
*/
if (uh->uh_sum) {
bzero(((struct ipovly *)ip)->ih_x1,
sizeof ((struct ipovly *)ip)->ih_x1);
((struct ipovly *)ip)->ih_len = uh->uh_ulen;
if ((uh->uh_sum = in_cksum(m, len + sizeof (struct ip))) != 0) {
udpstat.udps_badsum++;
m_freem(m);
return;
}
}
if (IN_MULTICAST(ip->ip_dst.s_addr) ||
in_broadcast(ip->ip_dst, m->m_pkthdr.rcvif)) {
struct inpcb *last;
/*
* Deliver a multicast or broadcast datagram to *all* sockets
* for which the local and remote addresses and ports match
* those of the incoming datagram. This allows more than
* one process to receive multi/broadcasts on the same port.
* (This really ought to be done for unicast datagrams as
* well, but that would cause problems with existing
* applications that open both address-specific sockets and
* a wildcard socket listening to the same port -- they would
* end up receiving duplicates of every unicast datagram.
* Those applications open the multiple sockets to overcome an
* inadequacy of the UDP socket interface, but for backwards
* compatibility we avoid the problem here rather than
* fixing the interface. Maybe 4.5BSD will remedy this?)
*/
/*
* Construct sockaddr format source address.
*/
udpsrc.sin_family = AF_INET;
udpsrc.sin_len = sizeof(struct sockaddr_in);
udpsrc.sin_addr = ip->ip_src;
udpsrc.sin_port = uh->uh_sport;
bzero((caddr_t)udpsrc.sin_zero, sizeof(udpsrc.sin_zero));
iphlen += sizeof(struct udphdr);
m->m_len -= iphlen;
m->m_pkthdr.len -= iphlen;
m->m_data += iphlen;
/*
* Locate pcb(s) for datagram.
* (Algorithm copied from raw_intr().)
*/
last = NULL;
for (inp = udbtable.inpt_queue.cqh_first;
inp != (struct inpcb *)&udbtable.inpt_queue;
inp = inp->inp_queue.cqe_next) {
if (inp->inp_lport != uh->uh_dport)
continue;
if (!in_nullhost(inp->inp_laddr)) {
if (!in_hosteq(inp->inp_laddr, ip->ip_dst))
continue;
}
if (!in_nullhost(inp->inp_faddr)) {
if (!in_hosteq(inp->inp_faddr, ip->ip_src) ||
inp->inp_fport != uh->uh_sport)
continue;
}
if (last != NULL) {
struct mbuf *n;
if ((n = m_copy(m, 0, M_COPYALL)) != NULL) {
if (last->inp_flags & INP_CONTROLOPTS
|| last->inp_socket->so_options &
SO_TIMESTAMP) {
ip_savecontrol(last, &opts,
ip, n);
}
if (sbappendaddr(
&last->inp_socket->so_rcv,
sintosa(&udpsrc), n, opts) == 0) {
m_freem(n);
if (opts)
m_freem(opts);
} else
sorwakeup(last->inp_socket);
opts = 0;
}
}
last = inp;
/*
* Don't look for additional matches if this one does
* not have either the SO_REUSEPORT or SO_REUSEADDR
* socket options set. This heuristic avoids searching
* through all pcbs in the common case of a non-shared
* port. It * assumes that an application will never
* clear these options after setting them.
*/
if ((last->inp_socket->so_options &
(SO_REUSEPORT|SO_REUSEADDR)) == 0)
break;
}
if (last == NULL) {
/*
* No matching pcb found; discard datagram.
* (No need to send an ICMP Port Unreachable
* for a broadcast or multicast datgram.)
*/
udpstat.udps_noportbcast++;
goto bad;
}
if (last->inp_flags & INP_CONTROLOPTS ||
last->inp_socket->so_options & SO_TIMESTAMP)
ip_savecontrol(last, &opts, ip, m);
if (sbappendaddr(&last->inp_socket->so_rcv,
sintosa(&udpsrc), m, opts) == 0) {
udpstat.udps_fullsock++;
goto bad;
}
sorwakeup(last->inp_socket);
return;
}
/*
* Locate pcb for datagram.
*/
inp = in_pcblookup_connect(&udbtable, ip->ip_src, uh->uh_sport,
ip->ip_dst, uh->uh_dport);
if (inp == 0) {
++udpstat.udps_pcbhashmiss;
inp = in_pcblookup_bind(&udbtable, ip->ip_dst, uh->uh_dport);
if (inp == 0) {
udpstat.udps_noport++;
if (m->m_flags & (M_BCAST | M_MCAST)) {
udpstat.udps_noportbcast++;
goto bad;
}
*ip = save_ip;
#if NIPKDB > 0
if (checkipkdb(&ip->ip_src,
uh->uh_sport,
uh->uh_dport,
m,
iphlen + sizeof(struct udphdr),
len - sizeof(struct udphdr)))
/* It was a debugger connect packet, just drop it now */
goto bad;
#endif
icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_PORT, 0, 0);
return;
}
}
/*
* Construct sockaddr format source address.
* Stuff source address and datagram in user buffer.
*/
udpsrc.sin_family = AF_INET;
udpsrc.sin_len = sizeof(struct sockaddr_in);
udpsrc.sin_addr = ip->ip_src;
udpsrc.sin_port = uh->uh_sport;
bzero((caddr_t)udpsrc.sin_zero, sizeof(udpsrc.sin_zero));
if (inp->inp_flags & INP_CONTROLOPTS ||
inp->inp_socket->so_options & SO_TIMESTAMP)
ip_savecontrol(inp, &opts, ip, m);
iphlen += sizeof(struct udphdr);
m->m_len -= iphlen;
m->m_pkthdr.len -= iphlen;
m->m_data += iphlen;
if (sbappendaddr(&inp->inp_socket->so_rcv, sintosa(&udpsrc), m,
opts) == 0) {
udpstat.udps_fullsock++;
goto bad;
}
sorwakeup(inp->inp_socket);
return;
bad:
m_freem(m);
if (opts)
m_freem(opts);
}
/*
* Notify a udp user of an asynchronous error;
* just wake up so that he can collect error status.
*/
static void
udp_notify(inp, errno)
register struct inpcb *inp;
int errno;
{
inp->inp_socket->so_error = errno;
sorwakeup(inp->inp_socket);
sowwakeup(inp->inp_socket);
}
void *
udp_ctlinput(cmd, sa, v)
int cmd;
struct sockaddr *sa;
void *v;
{
register struct ip *ip = v;
register struct udphdr *uh;
extern int inetctlerrmap[];
void (*notify) __P((struct inpcb *, int)) = udp_notify;
int errno;
if ((unsigned)cmd >= PRC_NCMDS)
return NULL;
errno = inetctlerrmap[cmd];
if (PRC_IS_REDIRECT(cmd))
notify = in_rtchange, ip = 0;
else if (cmd == PRC_HOSTDEAD)
ip = 0;
else if (errno == 0)
return NULL;
if (ip) {
uh = (struct udphdr *)((caddr_t)ip + (ip->ip_hl << 2));
in_pcbnotify(&udbtable, satosin(sa)->sin_addr, uh->uh_dport,
ip->ip_src, uh->uh_sport, errno, notify);
} else
in_pcbnotifyall(&udbtable, satosin(sa)->sin_addr, errno,
notify);
return NULL;
}
int
#if __STDC__
udp_output(struct mbuf *m, ...)
#else
udp_output(m, va_alist)
struct mbuf *m;
va_dcl
#endif
{
register struct inpcb *inp;
register struct udpiphdr *ui;
register int len = m->m_pkthdr.len;
int error = 0;
va_list ap;
va_start(ap, m);
inp = va_arg(ap, struct inpcb *);
va_end(ap);
/*
* Calculate data length and get a mbuf
* for UDP and IP headers.
*/
M_PREPEND(m, sizeof(struct udpiphdr), M_DONTWAIT);
if (m == 0) {
error = ENOBUFS;
goto release;
}
/*
* Compute the packet length of the IP header, and
* punt if the length looks bogus.
*/
if ((len + sizeof(struct udpiphdr)) > IP_MAXPACKET) {
error = EMSGSIZE;
goto release;
}
/*
* Fill in mbuf with extended UDP header
* and addresses and length put into network format.
*/
ui = mtod(m, struct udpiphdr *);
bzero(ui->ui_x1, sizeof ui->ui_x1);
ui->ui_pr = IPPROTO_UDP;
ui->ui_len = htons((u_int16_t)len + sizeof (struct udphdr));
ui->ui_src = inp->inp_laddr;
ui->ui_dst = inp->inp_faddr;
ui->ui_sport = inp->inp_lport;
ui->ui_dport = inp->inp_fport;
ui->ui_ulen = ui->ui_len;
/*
* Stuff checksum and output datagram.
*/
ui->ui_sum = 0;
if (udpcksum) {
if ((ui->ui_sum = in_cksum(m, sizeof (struct udpiphdr) + len)) == 0)
ui->ui_sum = 0xffff;
}
((struct ip *)ui)->ip_len = sizeof (struct udpiphdr) + len;
((struct ip *)ui)->ip_ttl = inp->inp_ip.ip_ttl; /* XXX */
((struct ip *)ui)->ip_tos = inp->inp_ip.ip_tos; /* XXX */
udpstat.udps_opackets++;
return (ip_output(m, inp->inp_options, &inp->inp_route,
inp->inp_socket->so_options & (SO_DONTROUTE | SO_BROADCAST),
inp->inp_moptions));
release:
m_freem(m);
return (error);
}
int udp_sendspace = 9216; /* really max datagram size */
int udp_recvspace = 40 * (1024 + sizeof(struct sockaddr_in));
/* 40 1K datagrams */
/*ARGSUSED*/
int
udp_usrreq(so, req, m, nam, control, p)
struct socket *so;
int req;
struct mbuf *m, *nam, *control;
struct proc *p;
{
register struct inpcb *inp;
int s;
register int error = 0;
if (req == PRU_CONTROL)
return (in_control(so, (long)m, (caddr_t)nam,
(struct ifnet *)control, p));
s = splsoftnet();
inp = sotoinpcb(so);
#ifdef DIAGNOSTIC
if (req != PRU_SEND && req != PRU_SENDOOB && control)
panic("udp_usrreq: unexpected control mbuf");
#endif
if (inp == 0 && req != PRU_ATTACH) {
error = EINVAL;
goto release;
}
/*
* Note: need to block udp_input while changing
* the udp pcb queue and/or pcb addresses.
*/
switch (req) {
case PRU_ATTACH:
if (inp != 0) {
error = EISCONN;
break;
}
if (so->so_snd.sb_hiwat == 0 || so->so_rcv.sb_hiwat == 0) {
error = soreserve(so, udp_sendspace, udp_recvspace);
if (error)
break;
}
error = in_pcballoc(so, &udbtable);
if (error)
break;
inp = sotoinpcb(so);
inp->inp_ip.ip_ttl = ip_defttl;
break;
case PRU_DETACH:
in_pcbdetach(inp);
break;
case PRU_BIND:
error = in_pcbbind(inp, nam, p);
break;
case PRU_LISTEN:
error = EOPNOTSUPP;
break;
case PRU_CONNECT:
error = in_pcbconnect(inp, nam);
if (error)
break;
soisconnected(so);
break;
case PRU_CONNECT2:
error = EOPNOTSUPP;
break;
case PRU_DISCONNECT:
/*soisdisconnected(so);*/
so->so_state &= ~SS_ISCONNECTED; /* XXX */
in_pcbdisconnect(inp);
inp->inp_laddr = zeroin_addr; /* XXX */
in_pcbstate(inp, INP_BOUND); /* XXX */
break;
case PRU_SHUTDOWN:
socantsendmore(so);
break;
case PRU_RCVD:
error = EOPNOTSUPP;
break;
case PRU_SEND:
if (control && control->m_len) {
m_freem(control);
m_freem(m);
error = EINVAL;
break;
}
{
struct in_addr laddr; /* XXX */
if (nam) {
laddr = inp->inp_laddr; /* XXX */
if ((so->so_state & SS_ISCONNECTED) != 0) {
error = EISCONN;
goto die;
}
error = in_pcbconnect(inp, nam);
if (error) {
die:
m_freem(m);
break;
}
} else {
if ((so->so_state & SS_ISCONNECTED) == 0) {
error = ENOTCONN;
goto die;
}
}
error = udp_output(m, inp);
if (nam) {
in_pcbdisconnect(inp);
inp->inp_laddr = laddr; /* XXX */
in_pcbstate(inp, INP_BOUND); /* XXX */
}
}
break;
case PRU_SENSE:
/*
* stat: don't bother with a blocksize.
*/
splx(s);
return (0);
case PRU_RCVOOB:
error = EOPNOTSUPP;
break;
case PRU_SENDOOB:
m_freem(control);
m_freem(m);
error = EOPNOTSUPP;
break;
case PRU_SOCKADDR:
in_setsockaddr(inp, nam);
break;
case PRU_PEERADDR:
in_setpeeraddr(inp, nam);
break;
default:
panic("udp_usrreq");
}
release:
splx(s);
return (error);
}
/*
* Sysctl for udp variables.
*/
int
udp_sysctl(name, namelen, oldp, oldlenp, newp, newlen)
int *name;
u_int namelen;
void *oldp;
size_t *oldlenp;
void *newp;
size_t newlen;
{
/* All sysctl names at this level are terminal. */
if (namelen != 1)
return (ENOTDIR);
switch (name[0]) {
case UDPCTL_CHECKSUM:
return (sysctl_int(oldp, oldlenp, newp, newlen, &udpcksum));
case UDPCTL_SENDSPACE:
return (sysctl_int(oldp, oldlenp, newp, newlen,
&udp_sendspace));
case UDPCTL_RECVSPACE:
return (sysctl_int(oldp, oldlenp, newp, newlen,
&udp_recvspace));
default:
return (ENOPROTOOPT);
}
/* NOTREACHED */
}