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/*
* 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 <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 <net/if.h>
#include <net/route.h>
#include <netinet/in.h>
#include <netinet/in_systm.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>
/*
* UDP protocol implementation.
* Per RFC 768, August, 1980.
*/
#ifndef COMPAT_42
int udpcksum = 1;
#else
int udpcksum = 0; /* XXX */
#endif
struct sockaddr_in udp_in = { sizeof(udp_in), AF_INET };
struct inpcb *udp_last_inpcb = &udb;
static void udp_detach __P((struct inpcb *));
static void udp_notify __P((struct inpcb *, int));
static struct mbuf *udp_saveopt __P((caddr_t, int, int));
void
udp_init()
{
udb.inp_next = udb.inp_prev = &udb;
}
void
udp_input(m, iphlen)
register struct mbuf *m;
int iphlen;
{
register struct ip *ip;
register struct udphdr *uh;
register struct inpcb *inp;
struct mbuf *opts = 0;
int len;
struct ip save_ip;
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_short)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 (udpcksum && uh->uh_sum) {
((struct ipovly *)ip)->ih_next = 0;
((struct ipovly *)ip)->ih_prev = 0;
((struct ipovly *)ip)->ih_x1 = 0;
((struct ipovly *)ip)->ih_len = uh->uh_ulen;
if (uh->uh_sum = in_cksum(m, len + sizeof (struct ip))) {
udpstat.udps_badsum++;
m_freem(m);
return;
}
}
if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) ||
in_broadcast(ip->ip_dst, m->m_pkthdr.rcvif)) {
struct socket *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.
*/
udp_in.sin_port = uh->uh_sport;
udp_in.sin_addr = ip->ip_src;
m->m_len -= sizeof (struct udpiphdr);
m->m_data += sizeof (struct udpiphdr);
/*
* Locate pcb(s) for datagram.
* (Algorithm copied from raw_intr().)
*/
last = NULL;
for (inp = udb.inp_next; inp != &udb; inp = inp->inp_next) {
if (inp->inp_lport != uh->uh_dport)
continue;
if (inp->inp_laddr.s_addr != INADDR_ANY) {
if (inp->inp_laddr.s_addr !=
ip->ip_dst.s_addr)
continue;
}
if (inp->inp_faddr.s_addr != INADDR_ANY) {
if (inp->inp_faddr.s_addr !=
ip->ip_src.s_addr ||
inp->inp_fport != uh->uh_sport)
continue;
}
if (last != NULL) {
struct mbuf *n;
if ((n = m_copy(m, 0, M_COPYALL)) != NULL) {
if (sbappendaddr(&last->so_rcv,
(struct sockaddr *)&udp_in,
n, (struct mbuf *)0) == 0) {
m_freem(n);
udpstat.udps_fullsock++;
} else
sorwakeup(last);
}
}
last = inp->inp_socket;
/*
* 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->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 (sbappendaddr(&last->so_rcv, (struct sockaddr *)&udp_in,
m, (struct mbuf *)0) == 0) {
udpstat.udps_fullsock++;
goto bad;
}
sorwakeup(last);
return;
}
/*
* Locate pcb for datagram.
*/
inp = udp_last_inpcb;
if (inp->inp_lport != uh->uh_dport ||
inp->inp_fport != uh->uh_sport ||
inp->inp_faddr.s_addr != ip->ip_src.s_addr ||
inp->inp_laddr.s_addr != ip->ip_dst.s_addr) {
inp = in_pcblookup(&udb, ip->ip_src, uh->uh_sport,
ip->ip_dst, uh->uh_dport, INPLOOKUP_WILDCARD);
if (inp)
udp_last_inpcb = inp;
udpstat.udpps_pcbcachemiss++;
}
if (inp == 0) {
udpstat.udps_noport++;
if (m->m_flags & (M_BCAST | M_MCAST)) {
udpstat.udps_noportbcast++;
goto bad;
}
*ip = save_ip;
ip->ip_len += iphlen;
icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_PORT, 0, 0);
return;
}
/*
* Construct sockaddr format source address.
* Stuff source address and datagram in user buffer.
*/
udp_in.sin_port = uh->uh_sport;
udp_in.sin_addr = ip->ip_src;
if (inp->inp_flags & INP_CONTROLOPTS) {
struct mbuf **mp = &opts;
if (inp->inp_flags & INP_RECVDSTADDR) {
*mp = udp_saveopt((caddr_t) &ip->ip_dst,
sizeof(struct in_addr), IP_RECVDSTADDR);
if (*mp)
mp = &(*mp)->m_next;
}
#ifdef notyet
/* options were tossed above */
if (inp->inp_flags & INP_RECVOPTS) {
*mp = udp_saveopt((caddr_t) opts_deleted_above,
sizeof(struct in_addr), IP_RECVOPTS);
if (*mp)
mp = &(*mp)->m_next;
}
/* ip_srcroute doesn't do what we want here, need to fix */
if (inp->inp_flags & INP_RECVRETOPTS) {
*mp = udp_saveopt((caddr_t) ip_srcroute(),
sizeof(struct in_addr), IP_RECVRETOPTS);
if (*mp)
mp = &(*mp)->m_next;
}
#endif
}
iphlen += sizeof(struct udphdr);
m->m_len -= iphlen;
m->m_pkthdr.len -= iphlen;
m->m_data += iphlen;
if (sbappendaddr(&inp->inp_socket->so_rcv, (struct sockaddr *)&udp_in,
m, opts) == 0) {
udpstat.udps_fullsock++;
goto bad;
}
sorwakeup(inp->inp_socket);
return;
bad:
m_freem(m);
if (opts)
m_freem(opts);
}
/*
* Create a "control" mbuf containing the specified data
* with the specified type for presentation with a datagram.
*/
struct mbuf *
udp_saveopt(p, size, type)
caddr_t p;
register int size;
int type;
{
register struct cmsghdr *cp;
struct mbuf *m;
if ((m = m_get(M_DONTWAIT, MT_CONTROL)) == NULL)
return ((struct mbuf *) NULL);
cp = (struct cmsghdr *) mtod(m, struct cmsghdr *);
bcopy(p, CMSG_DATA(cp), size);
size += sizeof(*cp);
m->m_len = size;
cp->cmsg_len = size;
cp->cmsg_level = IPPROTO_IP;
cp->cmsg_type = type;
return (m);
}
/*
* 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, ip)
int cmd;
struct sockaddr *sa;
register struct ip *ip;
{
register struct udphdr *uh;
extern struct in_addr zeroin_addr;
extern u_char inetctlerrmap[];
if (!PRC_IS_REDIRECT(cmd) &&
((unsigned)cmd >= PRC_NCMDS || inetctlerrmap[cmd] == 0))
return;
if (ip) {
uh = (struct udphdr *)((caddr_t)ip + (ip->ip_hl << 2));
in_pcbnotify(&udb, sa, uh->uh_dport, ip->ip_src, uh->uh_sport,
cmd, udp_notify);
} else
in_pcbnotify(&udb, sa, 0, zeroin_addr, 0, cmd, udp_notify);
}
int
udp_output(inp, m, addr, control)
register struct inpcb *inp;
register struct mbuf *m;
struct mbuf *addr, *control;
{
register struct udpiphdr *ui;
register int len = m->m_pkthdr.len;
struct in_addr laddr;
int s, error = 0;
if (control)
m_freem(control); /* XXX */
if (addr) {
laddr = inp->inp_laddr;
if (inp->inp_faddr.s_addr != INADDR_ANY) {
error = EISCONN;
goto release;
}
/*
* Must block input while temporarily connected.
*/
s = splnet();
error = in_pcbconnect(inp, addr);
if (error) {
splx(s);
goto release;
}
} else {
if (inp->inp_faddr.s_addr == INADDR_ANY) {
error = ENOTCONN;
goto release;
}
}
/*
* 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;
}
/*
* Fill in mbuf with extended UDP header
* and addresses and length put into network format.
*/
ui = mtod(m, struct udpiphdr *);
ui->ui_next = ui->ui_prev = 0;
ui->ui_x1 = 0;
ui->ui_pr = IPPROTO_UDP;
ui->ui_len = htons((u_short)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++;
error = ip_output(m, inp->inp_options, &inp->inp_route,
inp->inp_socket->so_options & (SO_DONTROUTE | SO_BROADCAST),
inp->inp_moptions);
if (addr) {
in_pcbdisconnect(inp);
inp->inp_laddr = laddr;
splx(s);
}
return (error);
release:
m_freem(m);
return (error);
}
u_long udp_sendspace = 9216; /* really max datagram size */
u_long udp_recvspace = 40 * (1024 + sizeof(struct sockaddr_in));
/* 40 1K datagrams */
/*ARGSUSED*/
int
udp_usrreq(so, req, m, addr, control)
struct socket *so;
int req;
struct mbuf *m, *addr, *control;
{
struct inpcb *inp = sotoinpcb(so);
int error = 0;
int s;
if (req == PRU_CONTROL)
return (in_control(so, (int)m, (caddr_t)addr,
(struct ifnet *)control));
if (inp == NULL && 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 != NULL) {
error = EINVAL;
break;
}
s = splnet();
error = in_pcballoc(so, &udb);
splx(s);
if (error)
break;
error = soreserve(so, udp_sendspace, udp_recvspace);
if (error)
break;
((struct inpcb *) so->so_pcb)->inp_ip.ip_ttl = ip_defttl;
break;
case PRU_DETACH:
udp_detach(inp);
break;
case PRU_BIND:
s = splnet();
error = in_pcbbind(inp, addr);
splx(s);
break;
case PRU_LISTEN:
error = EOPNOTSUPP;
break;
case PRU_CONNECT:
if (inp->inp_faddr.s_addr != INADDR_ANY) {
error = EISCONN;
break;
}
s = splnet();
error = in_pcbconnect(inp, addr);
splx(s);
if (error == 0)
soisconnected(so);
break;
case PRU_CONNECT2:
error = EOPNOTSUPP;
break;
case PRU_ACCEPT:
error = EOPNOTSUPP;
break;
case PRU_DISCONNECT:
if (inp->inp_faddr.s_addr == INADDR_ANY) {
error = ENOTCONN;
break;
}
s = splnet();
in_pcbdisconnect(inp);
inp->inp_laddr.s_addr = INADDR_ANY;
splx(s);
so->so_state &= ~SS_ISCONNECTED; /* XXX */
break;
case PRU_SHUTDOWN:
socantsendmore(so);
break;
case PRU_SEND:
return (udp_output(inp, m, addr, control));
case PRU_ABORT:
soisdisconnected(so);
udp_detach(inp);
break;
case PRU_SOCKADDR:
in_setsockaddr(inp, addr);
break;
case PRU_PEERADDR:
in_setpeeraddr(inp, addr);
break;
case PRU_SENSE:
/*
* stat: don't bother with a blocksize.
*/
return (0);
case PRU_SENDOOB:
case PRU_FASTTIMO:
case PRU_SLOWTIMO:
case PRU_PROTORCV:
case PRU_PROTOSEND:
error = EOPNOTSUPP;
break;
case PRU_RCVD:
case PRU_RCVOOB:
return (EOPNOTSUPP); /* do not free mbuf's */
default:
panic("udp_usrreq");
}
release:
if (control) {
printf("udp control data unexpectedly retained\n");
m_freem(control);
}
if (m)
m_freem(m);
return (error);
}
static void
udp_detach(inp)
struct inpcb *inp;
{
int s = splnet();
if (inp == udp_last_inpcb)
udp_last_inpcb = &udb;
in_pcbdetach(inp);
splx(s);
}
/*
* Sysctl for udp variables.
*/
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));
default:
return (ENOPROTOOPT);
}
/* NOTREACHED */
}