iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

IPv6: Complete IPV6_DONTFRAG support

Browse Source 
Finally add support to detect a local IPV6_DONTFRAG event
and return the relevant data to the user if they've enabled
IPV6_RECVPATHMTU on the socket.  The next recvmsg() will
return no data, but have an IPV6_PATHMTU as ancillary data.

Signed-off-by: Brian Haley <brian.haley@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Brian Haley 2010-04-23 11:26:09 +00:00 committed by David S. Miller
parent 13b52cd446
commit 4b340ae20d
7 changed files with 116 additions and 8 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
include/linux/ipv6.h
View File

@ -257,6 +257,7 @@ struct inet6_skb_parm {
};
#define IP6CB(skb) ((struct inet6_skb_parm*)((skb)->cb))
#define IP6CBMTU(skb) ((struct ip6_mtuinfo *)((skb)->cb))
static inline int inet6_iif(const struct sk_buff *skb)
{
@ -366,6 +367,7 @@ struct ipv6_pinfo {
struct ipv6_txoptions *opt;
struct sk_buff *pktoptions;
struct sk_buff *rxpmtu;
struct {
struct ipv6_txoptions *opt;
u8 hop_limit;

2
include/net/ipv6.h
View File

@ -578,9 +578,11 @@ extern int ip6_datagram_connect(struct sock *sk,
struct sockaddr *addr, int addr_len);
extern int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len);
extern int ipv6_recv_rxpmtu(struct sock *sk, struct msghdr *msg, int len);
extern void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err, __be16 port,
u32 info, u8 *payload);
extern void ipv6_local_error(struct sock *sk, int err, struct flowi *fl, u32 info);
extern void ipv6_local_rxpmtu(struct sock *sk, struct flowi *fl, u32 mtu);
extern int inet6_release(struct socket *sock);
extern int inet6_bind(struct socket *sock, struct sockaddr *uaddr,

3
net/ipv6/af_inet6.c
View File

@ -417,6 +417,9 @@ void inet6_destroy_sock(struct sock *sk)
if ((skb = xchg(&np->pktoptions, NULL)) != NULL)
kfree_skb(skb);
if ((skb = xchg(&np->rxpmtu, NULL)) != NULL)
kfree_skb(skb);
/* Free flowlabels */
fl6_free_socklist(sk);

87
net/ipv6/datagram.c
View File

@ -278,6 +278,45 @@ void ipv6_local_error(struct sock *sk, int err, struct flowi *fl, u32 info)
kfree_skb(skb);
}
void ipv6_local_rxpmtu(struct sock *sk, struct flowi *fl, 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);
ipv6_addr_copy(&iph->daddr, &fl->fl6_dst);
mtu_info = IP6CBMTU(skb);
if (!mtu_info) {
kfree_skb(skb);
return;
}
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 = fl->oif;
ipv6_addr_copy(&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);
}
/*
* Handle MSG_ERRQUEUE
*/
@ -381,6 +420,54 @@ out:
return err;
}
/*
* Handle IPV6_RECVPATHMTU
*/
int ipv6_recv_rxpmtu(struct sock *sk, struct msghdr *msg, int len)
{
struct ipv6_pinfo *np = inet6_sk(sk);
struct sk_buff *skb;
struct sockaddr_in6 *sin;
struct ip6_mtuinfo mtu_info;
int err;
int copied;
err = -EAGAIN;
skb = xchg(&np->rxpmtu, NULL);
if (skb == NULL)
goto out;
copied = skb->len;
if (copied > len) {
msg->msg_flags |= MSG_TRUNC;
copied = len;
}
err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copied);
if (err)
goto out_free_skb;
sock_recv_timestamp(msg, sk, skb);
memcpy(&mtu_info, IP6CBMTU(skb), sizeof(mtu_info));
sin = (struct sockaddr_in6 *)msg->msg_name;
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;
ipv6_addr_copy(&sin->sin6_addr, &mtu_info.ip6m_addr.sin6_addr);
}
put_cmsg(msg, SOL_IPV6, IPV6_PATHMTU, sizeof(mtu_info), &mtu_info);
err = copied;
out_free_skb:
kfree_skb(skb);
out:
return err;
}
int datagram_recv_ctl(struct sock *sk, struct msghdr *msg, struct sk_buff *skb)

24
net/ipv6/ip6_output.c
View File

@ -1219,15 +1219,23 @@ int ip6_append_data(struct sock *sk, int getfrag(void *from, char *to,
*/
inet->cork.length += length;
if (((length > mtu) && (sk->sk_protocol == IPPROTO_UDP)) &&
(rt->u.dst.dev->features & NETIF_F_UFO)) {
if (length > mtu) {
int proto = sk->sk_protocol;
if (dontfrag && (proto == IPPROTO_UDP || proto == IPPROTO_RAW)){
ipv6_local_rxpmtu(sk, fl, mtu-exthdrlen);
return -EMSGSIZE;
}
err = ip6_ufo_append_data(sk, getfrag, from, length, hh_len,
fragheaderlen, transhdrlen, mtu,
flags);
if (err)
goto error;
return 0;
if (proto == IPPROTO_UDP &&
(rt->u.dst.dev->features & NETIF_F_UFO)) {
err = ip6_ufo_append_data(sk, getfrag, from, length,
hh_len, fragheaderlen,
transhdrlen, mtu, flags);
if (err)
goto error;
return 0;
}
}
if ((skb = skb_peek_tail(&sk->sk_write_queue)) == NULL)

3
net/ipv6/raw.c
View File

@ -461,6 +461,9 @@ static int rawv6_recvmsg(struct kiocb *iocb, struct sock *sk,
if (flags & MSG_ERRQUEUE)
return ipv6_recv_error(sk, msg, len);
if (np->rxpmtu && np->rxopt.bits.rxpmtu)
return ipv6_recv_rxpmtu(sk, msg, len);
skb = skb_recv_datagram(sk, flags, noblock, &err);
if (!skb)
goto out;

3
net/ipv6/udp.c
View File

@ -335,6 +335,9 @@ int udpv6_recvmsg(struct kiocb *iocb, struct sock *sk,
if (flags & MSG_ERRQUEUE)
return ipv6_recv_error(sk, msg, len);
if (np->rxpmtu && np->rxopt.bits.rxpmtu)
return ipv6_recv_rxpmtu(sk, msg, len);
try_again:
skb = __skb_recv_datagram(sk, flags | (noblock ? MSG_DONTWAIT : 0),
&peeked, &err);