NetBSD/sys/netinet6/udp6_output.c

427 lines
12 KiB
C

/* $NetBSD: udp6_output.c,v 1.45 2014/10/11 20:53:16 christos Exp $ */
/* $KAME: udp6_output.c,v 1.43 2001/10/15 09:19:52 itojun Exp $ */
/*
* Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
* 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. Neither the name of the project 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 PROJECT 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 PROJECT 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.
*/
/*
* Copyright (c) 1982, 1986, 1989, 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. 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_var.h 8.1 (Berkeley) 6/10/93
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: udp6_output.c,v 1.45 2014/10/11 20:53:16 christos Exp $");
#include "opt_inet.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 <sys/syslog.h>
#include <sys/kauth.h>
#include <sys/domain.h>
#include <net/if.h>
#include <net/route.h>
#include <net/if_types.h>
#include <netinet/in.h>
#include <netinet/in_var.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netinet/ip_var.h>
#include <netinet/in_pcb.h>
#include <netinet/udp.h>
#include <netinet/udp_var.h>
#include <netinet/udp_private.h>
#include <netinet/ip6.h>
#include <netinet6/ip6_var.h>
#include <netinet6/in6_pcb.h>
#include <netinet6/udp6_var.h>
#include <netinet6/udp6_private.h>
#include <netinet/icmp6.h>
#include <netinet6/ip6protosw.h>
#include <netinet6/scope6_var.h>
#include "faith.h"
#include <net/net_osdep.h>
/*
* UDP protocol inplementation.
* Per RFC 768, August, 1980.
*/
int
udp6_output(struct in6pcb * const in6p, struct mbuf *m,
struct mbuf * const addr6, struct mbuf * const control,
struct lwp * const l)
{
struct rtentry *rt;
u_int32_t ulen = m->m_pkthdr.len;
u_int32_t plen = sizeof(struct udphdr) + ulen;
struct ip6_hdr *ip6;
struct udphdr *udp6;
struct in6_addr *laddr, *faddr;
struct in6_addr laddr_mapped; /* XXX ugly */
struct sockaddr_in6 *sin6 = NULL;
struct ifnet *oifp = NULL;
int scope_ambiguous = 0;
u_int16_t fport;
int error = 0;
struct ip6_pktopts *optp = NULL;
struct ip6_pktopts opt;
int af = AF_INET6, hlen = sizeof(struct ip6_hdr);
#ifdef INET
struct ip *ip;
struct udpiphdr *ui;
int flags = 0;
#endif
struct sockaddr_in6 tmp;
if (addr6) {
if (addr6->m_len != sizeof(*sin6)) {
error = EINVAL;
goto release;
}
sin6 = mtod(addr6, struct sockaddr_in6 *);
if (sin6->sin6_family != AF_INET6) {
error = EAFNOSUPPORT;
goto release;
}
/* protect *sin6 from overwrites */
tmp = *sin6;
sin6 = &tmp;
/*
* Application should provide a proper zone ID or the use of
* default zone IDs should be enabled. Unfortunately, some
* applications do not behave as it should, so we need a
* workaround. Even if an appropriate ID is not determined,
* we'll see if we can determine the outgoing interface. If we
* can, determine the zone ID based on the interface below.
*/
if (sin6->sin6_scope_id == 0 && !ip6_use_defzone)
scope_ambiguous = 1;
if ((error = sa6_embedscope(sin6, ip6_use_defzone)) != 0)
goto release;
}
if (control) {
if ((error = ip6_setpktopts(control, &opt,
in6p->in6p_outputopts, l->l_cred, IPPROTO_UDP)) != 0)
goto release;
optp = &opt;
} else
optp = in6p->in6p_outputopts;
if (sin6) {
/*
* IPv4 version of udp_output calls in_pcbconnect in this case,
* which needs splnet and affects performance.
* We have to do this as well, since in6_pcbsetport needs to
* know the foreign address for some of the algorithms that
* it employs.
*/
if (sin6->sin6_port == 0) {
error = EADDRNOTAVAIL;
goto release;
}
if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr)) {
/* how about ::ffff:0.0.0.0 case? */
error = EISCONN;
goto release;
}
faddr = &sin6->sin6_addr;
fport = sin6->sin6_port; /* allow 0 port */
if (IN6_IS_ADDR_V4MAPPED(faddr)) {
if ((in6p->in6p_flags & IN6P_IPV6_V6ONLY))
{
/*
* I believe we should explicitly discard the
* packet when mapped addresses are disabled,
* rather than send the packet as an IPv6 one.
* If we chose the latter approach, the packet
* might be sent out on the wire based on the
* default route, the situation which we'd
* probably want to avoid.
* (20010421 jinmei@kame.net)
*/
error = EINVAL;
goto release;
}
if (!IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr)
&& !IN6_IS_ADDR_V4MAPPED(&in6p->in6p_laddr)) {
/*
* when remote addr is an IPv4-mapped address,
* local addr should not be an IPv6 address,
* since you cannot determine how to map IPv6
* source address to IPv4.
*/
error = EINVAL;
goto release;
}
af = AF_INET;
}
if (!IN6_IS_ADDR_V4MAPPED(faddr)) {
laddr = in6_selectsrc(sin6, optp,
in6p->in6p_moptions,
&in6p->in6p_route,
&in6p->in6p_laddr, &oifp, &error);
if (oifp && scope_ambiguous &&
(error = in6_setscope(&sin6->sin6_addr,
oifp, NULL))) {
goto release;
}
} else {
/*
* XXX: freebsd[34] does not have in_selectsrc, but
* we can omit the whole part because freebsd4 calls
* udp_output() directly in this case, and thus we'll
* never see this path.
*/
if (IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_laddr)) {
struct sockaddr_in *sinp, sin_dst;
struct in_addr ina;
memcpy(&ina, &faddr->s6_addr[12], sizeof(ina));
sockaddr_in_init(&sin_dst, &ina, 0);
sinp = in_selectsrc(&sin_dst, &in6p->in6p_route,
in6p->in6p_socket->so_options, NULL,
&error);
if (sinp == NULL) {
if (error == 0)
error = EADDRNOTAVAIL;
goto release;
}
memset(&laddr_mapped, 0, sizeof(laddr_mapped));
laddr_mapped.s6_addr16[5] = 0xffff; /* ugly */
memcpy(&laddr_mapped.s6_addr[12],
&sinp->sin_addr,
sizeof(sinp->sin_addr));
laddr = &laddr_mapped;
} else
{
laddr = &in6p->in6p_laddr; /* XXX */
}
}
if (laddr == NULL) {
if (error == 0)
error = EADDRNOTAVAIL;
goto release;
}
if (in6p->in6p_lport == 0) {
/*
* Craft a sockaddr_in6 for the local endpoint. Use the
* "any" as a base, set the address, and recover the
* scope.
*/
struct sockaddr_in6 lsin6 =
*((const struct sockaddr_in6 *)in6p->in6p_socket->so_proto->pr_domain->dom_sa_any);
lsin6.sin6_addr = *laddr;
error = sa6_recoverscope(&lsin6);
if (error)
goto release;
error = in6_pcbsetport(&lsin6, in6p, l);
if (error) {
in6p->in6p_laddr = in6addr_any;
goto release;
}
}
} else {
if (IN6_IS_ADDR_UNSPECIFIED(&in6p->in6p_faddr)) {
error = ENOTCONN;
goto release;
}
if (IN6_IS_ADDR_V4MAPPED(&in6p->in6p_faddr)) {
if ((in6p->in6p_flags & IN6P_IPV6_V6ONLY))
{
/*
* XXX: this case would happen when the
* application sets the V6ONLY flag after
* connecting the foreign address.
* Such applications should be fixed,
* so we bark here.
*/
log(LOG_INFO, "udp6_output: IPV6_V6ONLY "
"option was set for a connected socket\n");
error = EINVAL;
goto release;
} else
af = AF_INET;
}
laddr = &in6p->in6p_laddr;
faddr = &in6p->in6p_faddr;
fport = in6p->in6p_fport;
}
if (af == AF_INET)
hlen = sizeof(struct ip);
/*
* Calculate data length and get a mbuf
* for UDP and IP6 headers.
*/
M_PREPEND(m, hlen + sizeof(struct udphdr), M_DONTWAIT);
if (m == 0) {
error = ENOBUFS;
goto release;
}
/*
* Stuff checksum and output datagram.
*/
udp6 = (struct udphdr *)(mtod(m, char *) + hlen);
udp6->uh_sport = in6p->in6p_lport; /* lport is always set in the PCB */
udp6->uh_dport = fport;
if (plen <= 0xffff)
udp6->uh_ulen = htons((u_int16_t)plen);
else
udp6->uh_ulen = 0;
udp6->uh_sum = 0;
switch (af) {
case AF_INET6:
ip6 = mtod(m, struct ip6_hdr *);
ip6->ip6_flow = in6p->in6p_flowinfo & IPV6_FLOWINFO_MASK;
ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
ip6->ip6_vfc |= IPV6_VERSION;
#if 0 /* ip6_plen will be filled in ip6_output. */
ip6->ip6_plen = htons((u_int16_t)plen);
#endif
ip6->ip6_nxt = IPPROTO_UDP;
ip6->ip6_hlim = in6_selecthlim(in6p,
(rt = rtcache_validate(&in6p->in6p_route)) != NULL
? rt->rt_ifp : NULL);
ip6->ip6_src = *laddr;
ip6->ip6_dst = *faddr;
udp6->uh_sum = in6_cksum_phdr(laddr, faddr,
htonl(plen), htonl(IPPROTO_UDP));
m->m_pkthdr.csum_flags = M_CSUM_UDPv6;
m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum);
UDP6_STATINC(UDP6_STAT_OPACKETS);
error = ip6_output(m, optp, &in6p->in6p_route, 0,
in6p->in6p_moptions, in6p->in6p_socket, NULL);
break;
case AF_INET:
#ifdef INET
/* can't transmit jumbogram over IPv4 */
if (plen > 0xffff) {
error = EMSGSIZE;
goto release;
}
ip = mtod(m, struct ip *);
ui = (struct udpiphdr *)ip;
memset(ui->ui_x1, 0, sizeof(ui->ui_x1));
ui->ui_pr = IPPROTO_UDP;
ui->ui_len = htons(plen);
memcpy(&ui->ui_src, &laddr->s6_addr[12], sizeof(ui->ui_src));
ui->ui_ulen = ui->ui_len;
flags = (in6p->in6p_socket->so_options &
(SO_DONTROUTE | SO_BROADCAST));
memcpy(&ui->ui_dst, &faddr->s6_addr[12], sizeof(ui->ui_dst));
udp6->uh_sum = in_cksum(m, hlen + plen);
if (udp6->uh_sum == 0)
udp6->uh_sum = 0xffff;
ip->ip_len = htons(hlen + plen);
ip->ip_ttl = in6_selecthlim(in6p, NULL); /* XXX */
ip->ip_tos = 0; /* XXX */
UDP_STATINC(UDP_STAT_OPACKETS);
error = ip_output(m, NULL, &in6p->in6p_route, flags /* XXX */,
in6p->in6p_v4moptions, (struct socket *)in6p->in6p_socket);
break;
#else
error = EAFNOSUPPORT;
goto release;
#endif
}
goto releaseopt;
release:
m_freem(m);
releaseopt:
if (control) {
if (optp == &opt)
ip6_clearpktopts(&opt, -1);
m_freem(control);
}
return (error);
}