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datagram.c
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datagram.c
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/*
* common UDP/RAW code
* Linux INET6 implementation
*
* Authors:
* Pedro Roque <[email protected]>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <linux/capability.h>
#include <linux/errno.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/interrupt.h>
#include <linux/socket.h>
#include <linux/sockios.h>
#include <linux/in6.h>
#include <linux/ipv6.h>
#include <linux/route.h>
#include <linux/slab.h>
#include <linux/export.h>
#include <net/ipv6.h>
#include <net/ndisc.h>
#include <net/addrconf.h>
#include <net/transp_v6.h>
#include <net/ip6_route.h>
#include <net/tcp_states.h>
#include <net/dsfield.h>
#include <linux/errqueue.h>
#include <linux/uaccess.h>
static bool ipv6_mapped_addr_any(const struct in6_addr *a)
{
return ipv6_addr_v4mapped(a) && (a->s6_addr32[3] == 0);
}
static void ip6_datagram_flow_key_init(struct flowi6 *fl6, struct sock *sk)
{
struct inet_sock *inet = inet_sk(sk);
struct ipv6_pinfo *np = inet6_sk(sk);
memset(fl6, 0, sizeof(*fl6));
fl6->flowi6_proto = sk->sk_protocol;
fl6->daddr = sk->sk_v6_daddr;
fl6->saddr = np->saddr;
fl6->flowi6_oif = sk->sk_bound_dev_if;
fl6->flowi6_mark = sk->sk_mark;
fl6->fl6_dport = inet->inet_dport;
fl6->fl6_sport = inet->inet_sport;
fl6->flowlabel = np->flow_label;
fl6->flowi6_uid = sk->sk_uid;
if (!fl6->flowi6_oif)
fl6->flowi6_oif = np->sticky_pktinfo.ipi6_ifindex;
if (!fl6->flowi6_oif && ipv6_addr_is_multicast(&fl6->daddr))
fl6->flowi6_oif = np->mcast_oif;
security_sk_classify_flow(sk, flowi6_to_flowi(fl6));
}
int ip6_datagram_dst_update(struct sock *sk, bool fix_sk_saddr)
{
struct ip6_flowlabel *flowlabel = NULL;
struct in6_addr *final_p, final;
struct ipv6_txoptions *opt;
struct dst_entry *dst;
struct inet_sock *inet = inet_sk(sk);
struct ipv6_pinfo *np = inet6_sk(sk);
struct flowi6 fl6;
int err = 0;
if (np->sndflow && (np->flow_label & IPV6_FLOWLABEL_MASK)) {
flowlabel = fl6_sock_lookup(sk, np->flow_label);
if (!flowlabel)
return -EINVAL;
}
ip6_datagram_flow_key_init(&fl6, sk);
rcu_read_lock();
opt = flowlabel ? flowlabel->opt : rcu_dereference(np->opt);
final_p = fl6_update_dst(&fl6, opt, &final);
rcu_read_unlock();
dst = ip6_dst_lookup_flow(sk, &fl6, final_p);
if (IS_ERR(dst)) {
err = PTR_ERR(dst);
goto out;
}
if (fix_sk_saddr) {
if (ipv6_addr_any(&np->saddr))
np->saddr = fl6.saddr;
if (ipv6_addr_any(&sk->sk_v6_rcv_saddr)) {
sk->sk_v6_rcv_saddr = fl6.saddr;
inet->inet_rcv_saddr = LOOPBACK4_IPV6;
if (sk->sk_prot->rehash)
sk->sk_prot->rehash(sk);
}
}
ip6_dst_store(sk, dst,
ipv6_addr_equal(&fl6.daddr, &sk->sk_v6_daddr) ?
&sk->sk_v6_daddr : NULL,
#ifdef CONFIG_IPV6_SUBTREES
ipv6_addr_equal(&fl6.saddr, &np->saddr) ?
&np->saddr :
#endif
NULL);
out:
fl6_sock_release(flowlabel);
return err;
}
void ip6_datagram_release_cb(struct sock *sk)
{
struct dst_entry *dst;
if (ipv6_addr_v4mapped(&sk->sk_v6_daddr))
return;
rcu_read_lock();
dst = __sk_dst_get(sk);
if (!dst || !dst->obsolete ||
dst->ops->check(dst, inet6_sk(sk)->dst_cookie)) {
rcu_read_unlock();
return;
}
rcu_read_unlock();
ip6_datagram_dst_update(sk, false);
}
EXPORT_SYMBOL_GPL(ip6_datagram_release_cb);
int __ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr,
int addr_len)
{
struct sockaddr_in6 *usin = (struct sockaddr_in6 *) uaddr;
struct inet_sock *inet = inet_sk(sk);
struct ipv6_pinfo *np = inet6_sk(sk);
struct in6_addr *daddr;
int addr_type;
int err;
__be32 fl6_flowlabel = 0;
if (usin->sin6_family == AF_INET) {
if (__ipv6_only_sock(sk))
return -EAFNOSUPPORT;
err = __ip4_datagram_connect(sk, uaddr, addr_len);
goto ipv4_connected;
}
if (addr_len < SIN6_LEN_RFC2133)
return -EINVAL;
if (usin->sin6_family != AF_INET6)
return -EAFNOSUPPORT;
if (np->sndflow)
fl6_flowlabel = usin->sin6_flowinfo & IPV6_FLOWINFO_MASK;
if (ipv6_addr_any(&usin->sin6_addr)) {
/*
* connect to self
*/
if (ipv6_addr_v4mapped(&sk->sk_v6_rcv_saddr))
ipv6_addr_set_v4mapped(htonl(INADDR_LOOPBACK),
&usin->sin6_addr);
else
usin->sin6_addr = in6addr_loopback;
}
addr_type = ipv6_addr_type(&usin->sin6_addr);
daddr = &usin->sin6_addr;
if (addr_type & IPV6_ADDR_MAPPED) {
struct sockaddr_in sin;
if (__ipv6_only_sock(sk)) {
err = -ENETUNREACH;
goto out;
}
sin.sin_family = AF_INET;
sin.sin_addr.s_addr = daddr->s6_addr32[3];
sin.sin_port = usin->sin6_port;
err = __ip4_datagram_connect(sk,
(struct sockaddr *) &sin,
sizeof(sin));
ipv4_connected:
if (err)
goto out;
ipv6_addr_set_v4mapped(inet->inet_daddr, &sk->sk_v6_daddr);
if (ipv6_addr_any(&np->saddr) ||
ipv6_mapped_addr_any(&np->saddr))
ipv6_addr_set_v4mapped(inet->inet_saddr, &np->saddr);
if (ipv6_addr_any(&sk->sk_v6_rcv_saddr) ||
ipv6_mapped_addr_any(&sk->sk_v6_rcv_saddr)) {
ipv6_addr_set_v4mapped(inet->inet_rcv_saddr,
&sk->sk_v6_rcv_saddr);
if (sk->sk_prot->rehash)
sk->sk_prot->rehash(sk);
}
goto out;
}
if (__ipv6_addr_needs_scope_id(addr_type)) {
if (addr_len >= sizeof(struct sockaddr_in6) &&
usin->sin6_scope_id) {
if (sk->sk_bound_dev_if &&
sk->sk_bound_dev_if != usin->sin6_scope_id) {
err = -EINVAL;
goto out;
}
sk->sk_bound_dev_if = usin->sin6_scope_id;
}
if (!sk->sk_bound_dev_if && (addr_type & IPV6_ADDR_MULTICAST))
sk->sk_bound_dev_if = np->mcast_oif;
/* Connect to link-local address requires an interface */
if (!sk->sk_bound_dev_if) {
err = -EINVAL;
goto out;
}
}
sk->sk_v6_daddr = *daddr;
np->flow_label = fl6_flowlabel;
inet->inet_dport = usin->sin6_port;
/*
* Check for a route to destination an obtain the
* destination cache for it.
*/
err = ip6_datagram_dst_update(sk, true);
if (err) {
/* Reset daddr and dport so that udp_v6_early_demux()
* fails to find this socket
*/
memset(&sk->sk_v6_daddr, 0, sizeof(sk->sk_v6_daddr));
inet->inet_dport = 0;
goto out;
}
sk->sk_state = TCP_ESTABLISHED;
sk_set_txhash(sk);
out:
return err;
}
EXPORT_SYMBOL_GPL(__ip6_datagram_connect);
int ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
{
int res;
lock_sock(sk);
res = __ip6_datagram_connect(sk, uaddr, addr_len);
release_sock(sk);
return res;
}
EXPORT_SYMBOL_GPL(ip6_datagram_connect);
int ip6_datagram_connect_v6_only(struct sock *sk, struct sockaddr *uaddr,
int addr_len)
{
DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, uaddr);
if (sin6->sin6_family != AF_INET6)
return -EAFNOSUPPORT;
return ip6_datagram_connect(sk, uaddr, addr_len);
}
EXPORT_SYMBOL_GPL(ip6_datagram_connect_v6_only);
void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
__be16 port, u32 info, u8 *payload)
{
struct ipv6_pinfo *np = inet6_sk(sk);
struct icmp6hdr *icmph = icmp6_hdr(skb);
struct sock_exterr_skb *serr;
if (!np->recverr)
return;
skb = skb_clone(skb, GFP_ATOMIC);
if (!skb)
return;
skb->protocol = htons(ETH_P_IPV6);
serr = SKB_EXT_ERR(skb);
serr->ee.ee_errno = err;
serr->ee.ee_origin = SO_EE_ORIGIN_ICMP6;
serr->ee.ee_type = icmph->icmp6_type;
serr->ee.ee_code = icmph->icmp6_code;
serr->ee.ee_pad = 0;
serr->ee.ee_info = info;
serr->ee.ee_data = 0;
serr->addr_offset = (u8 *)&(((struct ipv6hdr *)(icmph + 1))->daddr) -
skb_network_header(skb);
serr->port = port;
__skb_pull(skb, payload - skb->data);
skb_reset_transport_header(skb);
if (sock_queue_err_skb(sk, skb))
kfree_skb(skb);
}
void ipv6_local_error(struct sock *sk, int err, struct flowi6 *fl6, u32 info)
{
const struct ipv6_pinfo *np = inet6_sk(sk);
struct sock_exterr_skb *serr;
struct ipv6hdr *iph;
struct sk_buff *skb;
if (!np->recverr)
return;
skb = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC);
if (!skb)
return;
skb->protocol = htons(ETH_P_IPV6);
skb_put(skb, sizeof(struct ipv6hdr));
skb_reset_network_header(skb);
iph = ipv6_hdr(skb);
iph->daddr = fl6->daddr;
serr = SKB_EXT_ERR(skb);
serr->ee.ee_errno = err;
serr->ee.ee_origin = SO_EE_ORIGIN_LOCAL;
serr->ee.ee_type = 0;
serr->ee.ee_code = 0;
serr->ee.ee_pad = 0;
serr->ee.ee_info = info;
serr->ee.ee_data = 0;
serr->addr_offset = (u8 *)&iph->daddr - skb_network_header(skb);
serr->port = fl6->fl6_dport;
__skb_pull(skb, skb_tail_pointer(skb) - skb->data);
skb_reset_transport_header(skb);
if (sock_queue_err_skb(sk, skb))
kfree_skb(skb);
}
void ipv6_local_rxpmtu(struct sock *sk, struct flowi6 *fl6, u32 mtu)
{
struct ipv6_pinfo *np = inet6_sk(sk);
struct ipv6hdr *iph;
struct sk_buff *skb;
struct ip6_mtuinfo *mtu_info;
if (!np->rxopt.bits.rxpmtu)
return;
skb = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC);
if (!skb)
return;
skb_put(skb, sizeof(struct ipv6hdr));
skb_reset_network_header(skb);
iph = ipv6_hdr(skb);
iph->daddr = fl6->daddr;
mtu_info = IP6CBMTU(skb);
mtu_info->ip6m_mtu = mtu;
mtu_info->ip6m_addr.sin6_family = AF_INET6;
mtu_info->ip6m_addr.sin6_port = 0;
mtu_info->ip6m_addr.sin6_flowinfo = 0;
mtu_info->ip6m_addr.sin6_scope_id = fl6->flowi6_oif;
mtu_info->ip6m_addr.sin6_addr = ipv6_hdr(skb)->daddr;
__skb_pull(skb, skb_tail_pointer(skb) - skb->data);
skb_reset_transport_header(skb);
skb = xchg(&np->rxpmtu, skb);
kfree_skb(skb);
}
/* For some errors we have valid addr_offset even with zero payload and
* zero port. Also, addr_offset should be supported if port is set.
*/
static inline bool ipv6_datagram_support_addr(struct sock_exterr_skb *serr)
{
return serr->ee.ee_origin == SO_EE_ORIGIN_ICMP6 ||
serr->ee.ee_origin == SO_EE_ORIGIN_ICMP ||
serr->ee.ee_origin == SO_EE_ORIGIN_LOCAL || serr->port;
}
/* IPv6 supports cmsg on all origins aside from SO_EE_ORIGIN_LOCAL.
*
* At one point, excluding local errors was a quick test to identify icmp/icmp6
* errors. This is no longer true, but the test remained, so the v6 stack,
* unlike v4, also honors cmsg requests on all wifi and timestamp errors.
*/
static bool ip6_datagram_support_cmsg(struct sk_buff *skb,
struct sock_exterr_skb *serr)
{
if (serr->ee.ee_origin == SO_EE_ORIGIN_ICMP ||
serr->ee.ee_origin == SO_EE_ORIGIN_ICMP6)
return true;
if (serr->ee.ee_origin == SO_EE_ORIGIN_LOCAL)
return false;
if (!IP6CB(skb)->iif)
return false;
return true;
}
/*
* Handle MSG_ERRQUEUE
*/
int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len)
{
struct ipv6_pinfo *np = inet6_sk(sk);
struct sock_exterr_skb *serr;
struct sk_buff *skb;
DECLARE_SOCKADDR(struct sockaddr_in6 *, sin, msg->msg_name);
struct {
struct sock_extended_err ee;
struct sockaddr_in6 offender;
} errhdr;
int err;
int copied;
err = -EAGAIN;
skb = sock_dequeue_err_skb(sk);
if (!skb)
goto out;
copied = skb->len;
if (copied > len) {
msg->msg_flags |= MSG_TRUNC;
copied = len;
}
err = skb_copy_datagram_msg(skb, 0, msg, copied);
if (unlikely(err)) {
kfree_skb(skb);
return err;
}
sock_recv_timestamp(msg, sk, skb);
serr = SKB_EXT_ERR(skb);
if (sin && ipv6_datagram_support_addr(serr)) {
const unsigned char *nh = skb_network_header(skb);
sin->sin6_family = AF_INET6;
sin->sin6_flowinfo = 0;
sin->sin6_port = serr->port;
if (skb->protocol == htons(ETH_P_IPV6)) {
const struct ipv6hdr *ip6h = container_of((struct in6_addr *)(nh + serr->addr_offset),
struct ipv6hdr, daddr);
sin->sin6_addr = ip6h->daddr;
if (np->sndflow)
sin->sin6_flowinfo = ip6_flowinfo(ip6h);
sin->sin6_scope_id =
ipv6_iface_scope_id(&sin->sin6_addr,
IP6CB(skb)->iif);
} else {
ipv6_addr_set_v4mapped(*(__be32 *)(nh + serr->addr_offset),
&sin->sin6_addr);
sin->sin6_scope_id = 0;
}
*addr_len = sizeof(*sin);
}
memcpy(&errhdr.ee, &serr->ee, sizeof(struct sock_extended_err));
sin = &errhdr.offender;
memset(sin, 0, sizeof(*sin));
if (ip6_datagram_support_cmsg(skb, serr)) {
sin->sin6_family = AF_INET6;
if (np->rxopt.all)
ip6_datagram_recv_common_ctl(sk, msg, skb);
if (skb->protocol == htons(ETH_P_IPV6)) {
sin->sin6_addr = ipv6_hdr(skb)->saddr;
if (np->rxopt.all)
ip6_datagram_recv_specific_ctl(sk, msg, skb);
sin->sin6_scope_id =
ipv6_iface_scope_id(&sin->sin6_addr,
IP6CB(skb)->iif);
} else {
ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr,
&sin->sin6_addr);
if (inet_sk(sk)->cmsg_flags)
ip_cmsg_recv(msg, skb);
}
}
put_cmsg(msg, SOL_IPV6, IPV6_RECVERR, sizeof(errhdr), &errhdr);
/* Now we could try to dump offended packet options */
msg->msg_flags |= MSG_ERRQUEUE;
err = copied;
consume_skb(skb);
out:
return err;
}
EXPORT_SYMBOL_GPL(ipv6_recv_error);
/*
* Handle IPV6_RECVPATHMTU
*/
int ipv6_recv_rxpmtu(struct sock *sk, struct msghdr *msg, int len,
int *addr_len)
{
struct ipv6_pinfo *np = inet6_sk(sk);
struct sk_buff *skb;
struct ip6_mtuinfo mtu_info;
DECLARE_SOCKADDR(struct sockaddr_in6 *, sin, msg->msg_name);
int err;
int copied;
err = -EAGAIN;
skb = xchg(&np->rxpmtu, NULL);
if (!skb)
goto out;
copied = skb->len;
if (copied > len) {
msg->msg_flags |= MSG_TRUNC;
copied = len;
}
err = skb_copy_datagram_msg(skb, 0, msg, copied);
if (err)
goto out_free_skb;
sock_recv_timestamp(msg, sk, skb);
memcpy(&mtu_info, IP6CBMTU(skb), sizeof(mtu_info));
if (sin) {
sin->sin6_family = AF_INET6;
sin->sin6_flowinfo = 0;
sin->sin6_port = 0;
sin->sin6_scope_id = mtu_info.ip6m_addr.sin6_scope_id;
sin->sin6_addr = mtu_info.ip6m_addr.sin6_addr;
*addr_len = sizeof(*sin);
}
put_cmsg(msg, SOL_IPV6, IPV6_PATHMTU, sizeof(mtu_info), &mtu_info);
err = copied;
out_free_skb:
kfree_skb(skb);
out:
return err;
}
void ip6_datagram_recv_common_ctl(struct sock *sk, struct msghdr *msg,
struct sk_buff *skb)
{
struct ipv6_pinfo *np = inet6_sk(sk);
bool is_ipv6 = skb->protocol == htons(ETH_P_IPV6);
if (np->rxopt.bits.rxinfo) {
struct in6_pktinfo src_info;
if (is_ipv6) {
src_info.ipi6_ifindex = IP6CB(skb)->iif;
src_info.ipi6_addr = ipv6_hdr(skb)->daddr;
} else {
src_info.ipi6_ifindex =
PKTINFO_SKB_CB(skb)->ipi_ifindex;
ipv6_addr_set_v4mapped(ip_hdr(skb)->daddr,
&src_info.ipi6_addr);
}
if (src_info.ipi6_ifindex >= 0)
put_cmsg(msg, SOL_IPV6, IPV6_PKTINFO,
sizeof(src_info), &src_info);
}
}
void ip6_datagram_recv_specific_ctl(struct sock *sk, struct msghdr *msg,
struct sk_buff *skb)
{
struct ipv6_pinfo *np = inet6_sk(sk);
struct inet6_skb_parm *opt = IP6CB(skb);
unsigned char *nh = skb_network_header(skb);
if (np->rxopt.bits.rxhlim) {
int hlim = ipv6_hdr(skb)->hop_limit;
put_cmsg(msg, SOL_IPV6, IPV6_HOPLIMIT, sizeof(hlim), &hlim);
}
if (np->rxopt.bits.rxtclass) {
int tclass = ipv6_get_dsfield(ipv6_hdr(skb));
put_cmsg(msg, SOL_IPV6, IPV6_TCLASS, sizeof(tclass), &tclass);
}
if (np->rxopt.bits.rxflow) {
__be32 flowinfo = ip6_flowinfo((struct ipv6hdr *)nh);
if (flowinfo)
put_cmsg(msg, SOL_IPV6, IPV6_FLOWINFO, sizeof(flowinfo), &flowinfo);
}
/* HbH is allowed only once */
if (np->rxopt.bits.hopopts && (opt->flags & IP6SKB_HOPBYHOP)) {
u8 *ptr = nh + sizeof(struct ipv6hdr);
put_cmsg(msg, SOL_IPV6, IPV6_HOPOPTS, (ptr[1]+1)<<3, ptr);
}
if (opt->lastopt &&
(np->rxopt.bits.dstopts || np->rxopt.bits.srcrt)) {
/*
* Silly enough, but we need to reparse in order to
* report extension headers (except for HbH)
* in order.
*
* Also note that IPV6_RECVRTHDRDSTOPTS is NOT
* (and WILL NOT be) defined because
* IPV6_RECVDSTOPTS is more generic. --yoshfuji
*/
unsigned int off = sizeof(struct ipv6hdr);
u8 nexthdr = ipv6_hdr(skb)->nexthdr;
while (off <= opt->lastopt) {
unsigned int len;
u8 *ptr = nh + off;
switch (nexthdr) {
case IPPROTO_DSTOPTS:
nexthdr = ptr[0];
len = (ptr[1] + 1) << 3;
if (np->rxopt.bits.dstopts)
put_cmsg(msg, SOL_IPV6, IPV6_DSTOPTS, len, ptr);
break;
case IPPROTO_ROUTING:
nexthdr = ptr[0];
len = (ptr[1] + 1) << 3;
if (np->rxopt.bits.srcrt)
put_cmsg(msg, SOL_IPV6, IPV6_RTHDR, len, ptr);
break;
case IPPROTO_AH:
nexthdr = ptr[0];
len = (ptr[1] + 2) << 2;
break;
default:
nexthdr = ptr[0];
len = (ptr[1] + 1) << 3;
break;
}
off += len;
}
}
/* socket options in old style */
if (np->rxopt.bits.rxoinfo) {
struct in6_pktinfo src_info;
src_info.ipi6_ifindex = opt->iif;
src_info.ipi6_addr = ipv6_hdr(skb)->daddr;
put_cmsg(msg, SOL_IPV6, IPV6_2292PKTINFO, sizeof(src_info), &src_info);
}
if (np->rxopt.bits.rxohlim) {
int hlim = ipv6_hdr(skb)->hop_limit;
put_cmsg(msg, SOL_IPV6, IPV6_2292HOPLIMIT, sizeof(hlim), &hlim);
}
if (np->rxopt.bits.ohopopts && (opt->flags & IP6SKB_HOPBYHOP)) {
u8 *ptr = nh + sizeof(struct ipv6hdr);
put_cmsg(msg, SOL_IPV6, IPV6_2292HOPOPTS, (ptr[1]+1)<<3, ptr);
}
if (np->rxopt.bits.odstopts && opt->dst0) {
u8 *ptr = nh + opt->dst0;
put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr);
}
if (np->rxopt.bits.osrcrt && opt->srcrt) {
struct ipv6_rt_hdr *rthdr = (struct ipv6_rt_hdr *)(nh + opt->srcrt);
put_cmsg(msg, SOL_IPV6, IPV6_2292RTHDR, (rthdr->hdrlen+1) << 3, rthdr);
}
if (np->rxopt.bits.odstopts && opt->dst1) {
u8 *ptr = nh + opt->dst1;
put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr);
}
if (np->rxopt.bits.rxorigdstaddr) {
struct sockaddr_in6 sin6;
__be16 *ports = (__be16 *) skb_transport_header(skb);
if (skb_transport_offset(skb) + 4 <= (int)skb->len) {
/* All current transport protocols have the port numbers in the
* first four bytes of the transport header and this function is
* written with this assumption in mind.
*/
sin6.sin6_family = AF_INET6;
sin6.sin6_addr = ipv6_hdr(skb)->daddr;
sin6.sin6_port = ports[1];
sin6.sin6_flowinfo = 0;
sin6.sin6_scope_id =
ipv6_iface_scope_id(&ipv6_hdr(skb)->daddr,
opt->iif);
put_cmsg(msg, SOL_IPV6, IPV6_ORIGDSTADDR, sizeof(sin6), &sin6);
}
}
if (np->rxopt.bits.recvfragsize && opt->frag_max_size) {
int val = opt->frag_max_size;
put_cmsg(msg, SOL_IPV6, IPV6_RECVFRAGSIZE, sizeof(val), &val);
}
}
void ip6_datagram_recv_ctl(struct sock *sk, struct msghdr *msg,
struct sk_buff *skb)
{
ip6_datagram_recv_common_ctl(sk, msg, skb);
ip6_datagram_recv_specific_ctl(sk, msg, skb);
}
EXPORT_SYMBOL_GPL(ip6_datagram_recv_ctl);
int ip6_datagram_send_ctl(struct net *net, struct sock *sk,
struct msghdr *msg, struct flowi6 *fl6,
struct ipcm6_cookie *ipc6, struct sockcm_cookie *sockc)
{
struct in6_pktinfo *src_info;
struct cmsghdr *cmsg;
struct ipv6_rt_hdr *rthdr;
struct ipv6_opt_hdr *hdr;
struct ipv6_txoptions *opt = ipc6->opt;
int len;
int err = 0;
for_each_cmsghdr(cmsg, msg) {
int addr_type;
if (!CMSG_OK(msg, cmsg)) {
err = -EINVAL;
goto exit_f;
}
if (cmsg->cmsg_level == SOL_SOCKET) {
err = __sock_cmsg_send(sk, msg, cmsg, sockc);
if (err)
return err;
continue;
}
if (cmsg->cmsg_level != SOL_IPV6)
continue;
switch (cmsg->cmsg_type) {
case IPV6_PKTINFO:
case IPV6_2292PKTINFO:
{
struct net_device *dev = NULL;
if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct in6_pktinfo))) {
err = -EINVAL;
goto exit_f;
}
src_info = (struct in6_pktinfo *)CMSG_DATA(cmsg);
if (src_info->ipi6_ifindex) {
if (fl6->flowi6_oif &&
src_info->ipi6_ifindex != fl6->flowi6_oif)
return -EINVAL;
fl6->flowi6_oif = src_info->ipi6_ifindex;
}
addr_type = __ipv6_addr_type(&src_info->ipi6_addr);
rcu_read_lock();
if (fl6->flowi6_oif) {
dev = dev_get_by_index_rcu(net, fl6->flowi6_oif);
if (!dev) {
rcu_read_unlock();
return -ENODEV;
}
} else if (addr_type & IPV6_ADDR_LINKLOCAL) {
rcu_read_unlock();
return -EINVAL;
}
if (addr_type != IPV6_ADDR_ANY) {
int strict = __ipv6_addr_src_scope(addr_type) <= IPV6_ADDR_SCOPE_LINKLOCAL;
if (!(inet_sk(sk)->freebind || inet_sk(sk)->transparent) &&
!ipv6_chk_addr(net, &src_info->ipi6_addr,
strict ? dev : NULL, 0) &&
!ipv6_chk_acast_addr_src(net, dev,
&src_info->ipi6_addr))
err = -EINVAL;
else
fl6->saddr = src_info->ipi6_addr;
}
rcu_read_unlock();
if (err)
goto exit_f;
break;
}
case IPV6_FLOWINFO:
if (cmsg->cmsg_len < CMSG_LEN(4)) {
err = -EINVAL;
goto exit_f;
}
if (fl6->flowlabel&IPV6_FLOWINFO_MASK) {
if ((fl6->flowlabel^*(__be32 *)CMSG_DATA(cmsg))&~IPV6_FLOWINFO_MASK) {
err = -EINVAL;
goto exit_f;
}
}
fl6->flowlabel = IPV6_FLOWINFO_MASK & *(__be32 *)CMSG_DATA(cmsg);
break;
case IPV6_2292HOPOPTS:
case IPV6_HOPOPTS:
if (opt->hopopt || cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
err = -EINVAL;
goto exit_f;
}
hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
len = ((hdr->hdrlen + 1) << 3);
if (cmsg->cmsg_len < CMSG_LEN(len)) {
err = -EINVAL;
goto exit_f;
}
if (!ns_capable(net->user_ns, CAP_NET_RAW)) {
err = -EPERM;
goto exit_f;
}
opt->opt_nflen += len;
opt->hopopt = hdr;
break;
case IPV6_2292DSTOPTS:
if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
err = -EINVAL;
goto exit_f;
}
hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
len = ((hdr->hdrlen + 1) << 3);
if (cmsg->cmsg_len < CMSG_LEN(len)) {
err = -EINVAL;
goto exit_f;
}
if (!ns_capable(net->user_ns, CAP_NET_RAW)) {
err = -EPERM;
goto exit_f;
}
if (opt->dst1opt) {
err = -EINVAL;
goto exit_f;
}
opt->opt_flen += len;
opt->dst1opt = hdr;
break;
case IPV6_DSTOPTS:
case IPV6_RTHDRDSTOPTS:
if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_opt_hdr))) {
err = -EINVAL;
goto exit_f;
}
hdr = (struct ipv6_opt_hdr *)CMSG_DATA(cmsg);
len = ((hdr->hdrlen + 1) << 3);
if (cmsg->cmsg_len < CMSG_LEN(len)) {
err = -EINVAL;
goto exit_f;
}
if (!ns_capable(net->user_ns, CAP_NET_RAW)) {
err = -EPERM;
goto exit_f;
}
if (cmsg->cmsg_type == IPV6_DSTOPTS) {
opt->opt_flen += len;
opt->dst1opt = hdr;
} else {
opt->opt_nflen += len;
opt->dst0opt = hdr;
}
break;
case IPV6_2292RTHDR:
case IPV6_RTHDR:
if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct ipv6_rt_hdr))) {
err = -EINVAL;
goto exit_f;
}
rthdr = (struct ipv6_rt_hdr *)CMSG_DATA(cmsg);
switch (rthdr->type) {
#if IS_ENABLED(CONFIG_IPV6_MIP6)
case IPV6_SRCRT_TYPE_2:
if (rthdr->hdrlen != 2 ||
rthdr->segments_left != 1) {
err = -EINVAL;
goto exit_f;
}
break;
#endif
default:
err = -EINVAL;
goto exit_f;
}
len = ((rthdr->hdrlen + 1) << 3);
if (cmsg->cmsg_len < CMSG_LEN(len)) {
err = -EINVAL;
goto exit_f;
}
/* segments left must also match */
if ((rthdr->hdrlen >> 1) != rthdr->segments_left) {
err = -EINVAL;
goto exit_f;
}
opt->opt_nflen += len;
opt->srcrt = rthdr;
if (cmsg->cmsg_type == IPV6_2292RTHDR && opt->dst1opt) {
int dsthdrlen = ((opt->dst1opt->hdrlen+1)<<3);
opt->opt_nflen += dsthdrlen;
opt->dst0opt = opt->dst1opt;
opt->dst1opt = NULL;
opt->opt_flen -= dsthdrlen;
}
break;
case IPV6_2292HOPLIMIT:
case IPV6_HOPLIMIT:
if (cmsg->cmsg_len != CMSG_LEN(sizeof(int))) {
err = -EINVAL;
goto exit_f;
}
ipc6->hlimit = *(int *)CMSG_DATA(cmsg);
if (ipc6->hlimit < -1 || ipc6->hlimit > 0xff) {
err = -EINVAL;
goto exit_f;
}
break;
case IPV6_TCLASS:
{
int tc;
err = -EINVAL;
if (cmsg->cmsg_len != CMSG_LEN(sizeof(int)))
goto exit_f;
tc = *(int *)CMSG_DATA(cmsg);
if (tc < -1 || tc > 0xff)
goto exit_f;
err = 0;
ipc6->tclass = tc;
break;
}
case IPV6_DONTFRAG:
{
int df;
err = -EINVAL;
if (cmsg->cmsg_len != CMSG_LEN(sizeof(int)))
goto exit_f;
df = *(int *)CMSG_DATA(cmsg);