Commit 4b261c75 authored by Hannes Frederic Sowa's avatar Hannes Frederic Sowa Committed by David S. Miller
Browse files

ipv6: make IPV6_RECVPKTINFO work for ipv4 datagrams 



We currently don't report IPV6_RECVPKTINFO in cmsg access ancillary data
for IPv4 datagrams on IPv6 sockets.

This patch splits the ip6_datagram_recv_ctl into two functions, one
which handles both protocol families, AF_INET and AF_INET6, while the
ip6_datagram_recv_specific_ctl only handles IPv6 cmsg data.

ip6_datagram_recv_*_ctl never reported back any errors, so we can make
them return void. Also provide a helper for protocols which don't offer dual
personality to further use ip6_datagram_recv_ctl, which is exported to
modules.

I needed to shuffle the code for ping around a bit to make it easier to
implement dual personality for ping ipv6 sockets in future.

Reported-by: default avatarGert Doering <gert@space.net>
Signed-off-by: default avatarHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent a6e2fe17

include/linux/ipv6.h

+3 −0
Original line number Diff line number Diff line
@@ -284,6 +284,8 @@ static inline void inet_sk_copy_descendant(struct sock *sk_to, 


#define __ipv6_only_sock(sk)	(inet6_sk(sk)->ipv6only)

#define ipv6_only_sock(sk)	((sk)->sk_family == PF_INET6 && __ipv6_only_sock(sk))

#define ipv6_sk_rxinfo(sk)	((sk)->sk_family == PF_INET6 && \

				 inet6_sk(sk)->rxopt.bits.rxinfo)



static inline const struct in6_addr *inet6_rcv_saddr(const struct sock *sk)

{
@@ -300,6 +302,7 @@ static inline int inet_v6_ipv6only(const struct sock *sk) 
#else

#define __ipv6_only_sock(sk)	0

#define ipv6_only_sock(sk)	0

#define ipv6_sk_rxinfo(sk)	0



static inline struct ipv6_pinfo * inet6_sk(const struct sock *__sk)

{

include/net/ip.h

+1 −0
Original line number Diff line number Diff line
@@ -63,6 +63,7 @@ struct ipcm_cookie { 
};



#define IPCB(skb) ((struct inet_skb_parm*)((skb)->cb))

#define PKTINFO_SKB_CB(skb) ((struct in_pktinfo *)((skb)->cb))



struct ip_ra_chain {

	struct ip_ra_chain __rcu *next;

include/net/ping.h

+6 −2
Original line number Diff line number Diff line
@@ -33,7 +33,11 @@ 
struct pingv6_ops {

	int (*ipv6_recv_error)(struct sock *sk, struct msghdr *msg, int len,

			       int *addr_len);

	int (*ip6_datagram_recv_ctl)(struct sock *sk, struct msghdr *msg,

	void (*ip6_datagram_recv_common_ctl)(struct sock *sk,

					     struct msghdr *msg,

					     struct sk_buff *skb);

	void (*ip6_datagram_recv_specific_ctl)(struct sock *sk,

					       struct msghdr *msg,

					       struct sk_buff *skb);

	int (*icmpv6_err_convert)(u8 type, u8 code, int *err);

	void (*ipv6_icmp_error)(struct sock *sk, struct sk_buff *skb, int err,

include/net/transp_v6.h

+7 −2
Original line number Diff line number Diff line
@@ -32,7 +32,12 @@ void tcpv6_exit(void); 


int udpv6_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len);



int ip6_datagram_recv_ctl(struct sock *sk, struct msghdr *msg,

/* this does all the common and the specific ctl work */

void ip6_datagram_recv_ctl(struct sock *sk, struct msghdr *msg,

			   struct sk_buff *skb);

void ip6_datagram_recv_common_ctl(struct sock *sk, struct msghdr *msg,

				  struct sk_buff *skb);

void ip6_datagram_recv_specific_ctl(struct sock *sk, struct msghdr *msg,

				    struct sk_buff *skb);



int ip6_datagram_send_ctl(struct net *net, struct sock *sk, struct msghdr *msg,

net/ipv4/ip_sockglue.c

+3 −3
Original line number Diff line number Diff line
@@ -56,7 +56,6 @@ 
/*

 *	SOL_IP control messages.

 */

#define PKTINFO_SKB_CB(__skb) ((struct in_pktinfo *)((__skb)->cb))



static void ip_cmsg_recv_pktinfo(struct msghdr *msg, struct sk_buff *skb)

{
@@ -1055,9 +1054,10 @@ e_inval: 
void ipv4_pktinfo_prepare(const struct sock *sk, struct sk_buff *skb)

{

	struct in_pktinfo *pktinfo = PKTINFO_SKB_CB(skb);

	bool prepare = (inet_sk(sk)->cmsg_flags & IP_CMSG_PKTINFO) ||

		       ipv6_sk_rxinfo(sk);



	if ((inet_sk(sk)->cmsg_flags & IP_CMSG_PKTINFO) &&

	    skb_rtable(skb)) {

	if (prepare && skb_rtable(skb)) {

		pktinfo->ipi_ifindex = inet_iif(skb);

		pktinfo->ipi_spec_dst.s_addr = fib_compute_spec_dst(skb);

	} else {

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