static int
udp6_output(struct inpcb *inp, struct mbuf *m, struct sockaddr *addr6,
struct mbuf *control, struct thread *td)
{
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, in6a;
struct sockaddr_in6 *sin6 = NULL;
int cscov_partial = 0;
int scope_ambiguous = 0;
u_short fport;
int error = 0;
uint8_t nxt;
uint16_t cscov = 0;
struct ip6_pktopts *optp, opt;
int af = AF_INET6, hlen = sizeof(struct ip6_hdr);
int flags;
struct sockaddr_in6 tmp;
INP_WLOCK_ASSERT(inp);
INP_HASH_WLOCK_ASSERT(inp->inp_pcbinfo);
if (addr6) {
/* addr6 has been validated in udp6_send(). */
sin6 = (struct sockaddr_in6 *)addr6;
/* 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 && !V_ip6_use_defzone)
scope_ambiguous = 1;
if ((error = sa6_embedscope(sin6, V_ip6_use_defzone)) != 0)
return (error);
}
nxt = (inp->inp_socket->so_proto->pr_protocol == IPPROTO_UDP) ?
IPPROTO_UDP : IPPROTO_UDPLITE;
if (control) {
if ((error = ip6_setpktopts(control, &opt,
inp->in6p_outputopts, td->td_ucred, nxt)) != 0)
goto release;
optp = &opt;
} else
optp = inp->in6p_outputopts;
if (sin6) {
faddr = &sin6->sin6_addr;
/*
* Since we saw no essential reason for calling in_pcbconnect,
* we get rid of such kind of logic, and call in6_selectsrc
* and in6_pcbsetport in order to fill in the local address
* and the local port.
*/
if (sin6->sin6_port == 0) {
error = EADDRNOTAVAIL;
goto release;
}
if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
/* how about ::ffff:0.0.0.0 case? */
error = EISCONN;
goto release;
}
fport = sin6->sin6_port; /* allow 0 port */
if (IN6_IS_ADDR_V4MAPPED(faddr)) {
if ((inp->inp_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 [email protected])
*/
error = EINVAL;
goto release;
}
if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr) &&
!IN6_IS_ADDR_V4MAPPED(&inp->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)) {
error = in6_selectsrc_socket(sin6, optp, inp,
td->td_ucred, scope_ambiguous, &in6a, NULL);
if (error)
goto release;
laddr = &in6a;
} else
laddr = &inp->in6p_laddr; /* XXX */
if (laddr == NULL) {
if (error == 0)
error = EADDRNOTAVAIL;
goto release;
}
if (inp->inp_lport == 0 &&
(error = in6_pcbsetport(laddr, inp, td->td_ucred)) != 0) {
/* Undo an address bind that may have occurred. */
inp->in6p_laddr = in6addr_any;
goto release;
}
} else {
if (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) {
error = ENOTCONN;
goto release;
}
if (IN6_IS_ADDR_V4MAPPED(&inp->in6p_faddr)) {
if ((inp->inp_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 = &inp->in6p_laddr;
faddr = &inp->in6p_faddr;
fport = inp->inp_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_NOWAIT);
if (m == NULL) {
error = ENOBUFS;
goto release;
}
/*
* Stuff checksum and output datagram.
*/
udp6 = (struct udphdr *)(mtod(m, caddr_t) + hlen);
udp6->uh_sport = inp->inp_lport; /* lport is always set in the PCB */
udp6->uh_dport = fport;
if (nxt == IPPROTO_UDPLITE) {
struct udpcb *up;
up = intoudpcb(inp);
cscov = up->u_txcslen;
if (cscov >= plen)
cscov = 0;
udp6->uh_ulen = htons(cscov);
/*
* For UDP-Lite, checksum coverage length of zero means
* the entire UDPLite packet is covered by the checksum.
*/
cscov_partial = (cscov == 0) ? 0 : 1;
} else if (plen <= 0xffff)
udp6->uh_ulen = htons((u_short)plen);
else
udp6->uh_ulen = 0;
udp6->uh_sum = 0;
switch (af) {
case AF_INET6:
ip6 = mtod(m, struct ip6_hdr *);
ip6->ip6_flow = inp->inp_flow & IPV6_FLOWINFO_MASK;
ip6->ip6_vfc &= ~IPV6_VERSION_MASK;
ip6->ip6_vfc |= IPV6_VERSION;
ip6->ip6_plen = htons((u_short)plen);
ip6->ip6_nxt = nxt;
ip6->ip6_hlim = in6_selecthlim(inp, NULL);
ip6->ip6_src = *laddr;
ip6->ip6_dst = *faddr;
if (cscov_partial) {
if ((udp6->uh_sum = in6_cksum_partial(m, nxt,
sizeof(struct ip6_hdr), plen, cscov)) == 0)
udp6->uh_sum = 0xffff;
} else {
udp6->uh_sum = in6_cksum_pseudo(ip6, plen, nxt, 0);
m->m_pkthdr.csum_flags = CSUM_UDP_IPV6;
m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum);
}
#ifdef RSS
{
uint32_t hash_val, hash_type;
uint8_t pr;
pr = inp->inp_socket->so_proto->pr_protocol;
/*
* Calculate an appropriate RSS hash for UDP and
* UDP Lite.
*
* The called function will take care of figuring out
* whether a 2-tuple or 4-tuple hash is required based
* on the currently configured scheme.
*
* Later later on connected socket values should be
* cached in the inpcb and reused, rather than constantly
* re-calculating it.
*
* UDP Lite is a different protocol number and will
* likely end up being hashed as a 2-tuple until
* RSS / NICs grow UDP Lite protocol awareness.
*/
if (rss_proto_software_hash_v6(faddr, laddr, fport,
inp->inp_lport, pr, &hash_val, &hash_type) == 0) {
m->m_pkthdr.flowid = hash_val;
M_HASHTYPE_SET(m, hash_type);
}
}
#endif
flags = 0;
#ifdef RSS
/*
* Don't override with the inp cached flowid.
*
* Until the whole UDP path is vetted, it may actually
* be incorrect.
*/
flags |= IP_NODEFAULTFLOWID;
#endif
UDP_PROBE(send, NULL, inp, ip6, inp, udp6);
UDPSTAT_INC(udps_opackets);
error = ip6_output(m, optp, &inp->inp_route6, flags,
inp->in6p_moptions, NULL, inp);
break;
case AF_INET:
error = EAFNOSUPPORT;
goto release;
}
goto releaseopt;
release:
m_freem(m);
releaseopt:
if (control) {
ip6_clearpktopts(&opt, -1);
m_freem(control);
}
return (error);
}
/*
* Do a software calculation of the RSS for the given mbuf.
*
* This is typically used by the input path to recalculate the RSS after
* some form of packet processing (eg de-capsulation, IP fragment reassembly.)
*
* dir is the packet direction - RSS_HASH_PKT_INGRESS for incoming and
* RSS_HASH_PKT_EGRESS for outgoing.
*
* Returns 0 if a hash was done, -1 if no hash was done, +1 if
* the mbuf already had a valid RSS flowid.
*
* This function doesn't modify the mbuf. It's up to the caller to
* assign flowid/flowtype as appropriate.
*/
int
rss_mbuf_software_hash_v6(const struct mbuf *m, int dir, uint32_t *hashval,
uint32_t *hashtype)
{
const struct ip6_hdr *ip6;
const struct tcphdr *th;
const struct udphdr *uh;
uint32_t flowtype;
uint8_t proto;
int off, newoff;
int nxt;
/*
* XXX For now this only handles hashing on incoming mbufs.
*/
if (dir != RSS_HASH_PKT_INGRESS) {
RSS_DEBUG("called on EGRESS packet!\n");
return (-1);
}
off = sizeof(struct ip6_hdr);
/*
* First, validate that the mbuf we have is long enough
* to have an IPv6 header in it.
*/
if (m->m_pkthdr.len < off) {
RSS_DEBUG("short mbuf pkthdr\n");
return (-1);
}
if (m->m_len < off) {
RSS_DEBUG("short mbuf len\n");
return (-1);
}
/* Ok, let's dereference that */
ip6 = mtod(m, struct ip6_hdr *);
proto = ip6->ip6_nxt;
/*
* Find the beginning of the TCP/UDP header.
*
* If this is a fragment then it shouldn't be four-tuple
* hashed just yet. Once it's reassembled into a full
* frame it should be re-hashed.
*/
while (proto != IPPROTO_FRAGMENT) {
newoff = ip6_nexthdr(m, off, proto, &nxt);
if (newoff < 0)
break;
off = newoff;
proto = nxt;
}
/*
* If the mbuf flowid/flowtype matches the packet type,
* and we don't support the 4-tuple version of the given protocol,
* then signal to the owner that it can trust the flowid/flowtype
* details.
*
* This is a little picky - eg, if TCPv6 / UDPv6 hashing
* is supported but we got a TCP/UDP frame only 2-tuple hashed,
* then we shouldn't just "trust" the 2-tuple hash. We need
* a 4-tuple hash.
*/
flowtype = M_HASHTYPE_GET(m);
if (flowtype != M_HASHTYPE_NONE) {
switch (proto) {
case IPPROTO_UDP:
if ((rss_gethashconfig() & RSS_HASHTYPE_RSS_UDP_IPV6) &&
(flowtype == M_HASHTYPE_RSS_UDP_IPV6)) {
return (1);
}
/*
* Only allow 2-tuple for UDP frames if we don't also
* support 4-tuple for UDP.
*/
if ((rss_gethashconfig() & RSS_HASHTYPE_RSS_IPV6) &&
((rss_gethashconfig() & RSS_HASHTYPE_RSS_UDP_IPV6) == 0) &&
flowtype == M_HASHTYPE_RSS_IPV6) {
return (1);
}
break;
case IPPROTO_TCP:
if ((rss_gethashconfig() & RSS_HASHTYPE_RSS_TCP_IPV6) &&
(flowtype == M_HASHTYPE_RSS_TCP_IPV6)) {
return (1);
}
/*
* Only allow 2-tuple for TCP frames if we don't also
* support 4-tuple for TCP.
*/
if ((rss_gethashconfig() & RSS_HASHTYPE_RSS_IPV6) &&
((rss_gethashconfig() & RSS_HASHTYPE_RSS_TCP_IPV6) == 0) &&
flowtype == M_HASHTYPE_RSS_IPV6) {
return (1);
}
break;
default:
if ((rss_gethashconfig() & RSS_HASHTYPE_RSS_IPV6) &&
flowtype == M_HASHTYPE_RSS_IPV6) {
return (1);
}
break;
}
}
/*
* Decode enough information to make a hash decision.
*/
if ((rss_gethashconfig() & RSS_HASHTYPE_RSS_TCP_IPV6) &&
(proto == IPPROTO_TCP)) {
if (m->m_len < off + sizeof(struct tcphdr)) {
RSS_DEBUG("short TCP frame?\n");
return (-1);
}
th = (const struct tcphdr *)((c_caddr_t)ip6 + off);
return rss_proto_software_hash_v6(&ip6->ip6_src, &ip6->ip6_dst,
th->th_sport,
th->th_dport,
proto,
hashval,
hashtype);
} else if ((rss_gethashconfig() & RSS_HASHTYPE_RSS_UDP_IPV6) &&
(proto == IPPROTO_UDP)) {
if (m->m_len < off + sizeof(struct udphdr)) {
RSS_DEBUG("short UDP frame?\n");
return (-1);
}
uh = (const struct udphdr *)((c_caddr_t)ip6 + off);
return rss_proto_software_hash_v6(&ip6->ip6_src, &ip6->ip6_dst,
uh->uh_sport,
uh->uh_dport,
proto,
hashval,
hashtype);
} else if (rss_gethashconfig() & RSS_HASHTYPE_RSS_IPV6) {
/* Default to 2-tuple hash */
return rss_proto_software_hash_v6(&ip6->ip6_src, &ip6->ip6_dst,
0, /* source port */
0, /* destination port */
0, /* IPPROTO_IP */
hashval,
hashtype);
} else {
RSS_DEBUG("no available hashtypes!\n");
return (-1);
}
}