Commit b6c66c43 authored by David Howells's avatar David Howells
Browse files

rxrpc: Use the core ICMP/ICMP6 parsers 



Make rxrpc_encap_rcv_err() pass the ICMP/ICMP6 skbuff to ip_icmp_error() or
ipv6_icmp_error() as appropriate to do the parsing rather than trying to do
it in rxrpc.

This pushes an error report onto the UDP socket's error queue and calls
->sk_error_report() from which point rxrpc can pick it up.

It would be preferable to steal the packet directly from ip*_icmp_error()
rather than letting it get queued, but this is probably good enough.

Also note that __udp4_lib_err() calls sk_error_report() twice in some
cases.

Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
parent 42fb06b3

net/rxrpc/ar-internal.h

+0 −1
Original line number Diff line number Diff line
@@ -998,7 +998,6 @@ void rxrpc_send_keepalive(struct rxrpc_peer *); 
/*

 * peer_event.c

 */

void rxrpc_encap_err_rcv(struct sock *, struct sk_buff *, int, __be16, u32, u8 *);

void rxrpc_error_report(struct sock *);

void rxrpc_peer_keepalive_worker(struct work_struct *);

net/rxrpc/local_object.c

+13 −0
Original line number Diff line number Diff line
@@ -23,6 +23,19 @@ 
static void rxrpc_local_processor(struct work_struct *);

static void rxrpc_local_rcu(struct rcu_head *);



/*

 * Handle an ICMP/ICMP6 error turning up at the tunnel.  Push it through the

 * usual mechanism so that it gets parsed and presented through the UDP

 * socket's error_report().

 */

static void rxrpc_encap_err_rcv(struct sock *sk, struct sk_buff *skb, int err,

				__be16 port, u32 info, u8 *payload)

{

	if (ip_hdr(skb)->version == IPVERSION)

		return ip_icmp_error(sk, skb, err, port, info, payload);

	return ipv6_icmp_error(sk, skb, err, port, info, payload);

}



/*

 * Compare a local to an address.  Return -ve, 0 or +ve to indicate less than,

 * same or greater than.

net/rxrpc/peer_event.c

+29 −216
Original line number Diff line number Diff line
@@ -16,220 +16,12 @@ 
#include <net/sock.h>

#include <net/af_rxrpc.h>

#include <net/ip.h>

#include <net/icmp.h>

#include "ar-internal.h"



static void rxrpc_adjust_mtu(struct rxrpc_peer *, unsigned int);

static void rxrpc_store_error(struct rxrpc_peer *, struct sock_exterr_skb *);

static void rxrpc_distribute_error(struct rxrpc_peer *, int,

				   enum rxrpc_call_completion);



/*

 * Find the peer associated with an ICMPv4 packet.

 */

static struct rxrpc_peer *rxrpc_lookup_peer_icmp_rcu(struct rxrpc_local *local,

						     struct sk_buff *skb,

						     __be16 udp_port,

						     struct sockaddr_rxrpc *srx)

{

	struct iphdr *ip, *ip0 = ip_hdr(skb);

	struct icmphdr *icmp = icmp_hdr(skb);



	_enter("%u,%u,%u", ip0->protocol, icmp->type, icmp->code);



	switch (icmp->type) {

	case ICMP_DEST_UNREACH:

	case ICMP_TIME_EXCEEDED:

	case ICMP_PARAMETERPROB:

		ip = (struct iphdr *)((void *)icmp + 8);

		break;

	default:

		return NULL;

	}



	memset(srx, 0, sizeof(*srx));

	srx->transport_type = local->srx.transport_type;

	srx->transport_len = local->srx.transport_len;

	srx->transport.family = local->srx.transport.family;



	/* Can we see an ICMP4 packet on an ICMP6 listening socket?  and vice

	 * versa?

	 */

	switch (srx->transport.family) {

	case AF_INET:

		srx->transport_len = sizeof(srx->transport.sin);

		srx->transport.family = AF_INET;

		srx->transport.sin.sin_port = udp_port;

		memcpy(&srx->transport.sin.sin_addr, &ip->daddr,

		       sizeof(struct in_addr));

		break;



#ifdef CONFIG_AF_RXRPC_IPV6

	case AF_INET6:

		srx->transport_len = sizeof(srx->transport.sin);

		srx->transport.family = AF_INET;

		srx->transport.sin.sin_port = udp_port;

		memcpy(&srx->transport.sin.sin_addr, &ip->daddr,

		       sizeof(struct in_addr));

		break;

#endif



	default:

		WARN_ON_ONCE(1);

		return NULL;

	}



	_net("ICMP {%pISp}", &srx->transport);

	return rxrpc_lookup_peer_rcu(local, srx);

}



#ifdef CONFIG_AF_RXRPC_IPV6

/*

 * Find the peer associated with an ICMPv6 packet.

 */

static struct rxrpc_peer *rxrpc_lookup_peer_icmp6_rcu(struct rxrpc_local *local,

						      struct sk_buff *skb,

						      __be16 udp_port,

						      struct sockaddr_rxrpc *srx)

{

	struct icmp6hdr *icmp = icmp6_hdr(skb);

	struct ipv6hdr *ip, *ip0 = ipv6_hdr(skb);



	_enter("%u,%u,%u", ip0->nexthdr, icmp->icmp6_type, icmp->icmp6_code);



	switch (icmp->icmp6_type) {

	case ICMPV6_DEST_UNREACH:

	case ICMPV6_PKT_TOOBIG:

	case ICMPV6_TIME_EXCEED:

	case ICMPV6_PARAMPROB:

		ip = (struct ipv6hdr *)((void *)icmp + 8);

		break;

	default:

		return NULL;

	}



	memset(srx, 0, sizeof(*srx));

	srx->transport_type = local->srx.transport_type;

	srx->transport_len = local->srx.transport_len;

	srx->transport.family = local->srx.transport.family;



	/* Can we see an ICMP4 packet on an ICMP6 listening socket?  and vice

	 * versa?

	 */

	switch (srx->transport.family) {

	case AF_INET:

		_net("Rx ICMP6 on v4 sock");

		srx->transport_len = sizeof(srx->transport.sin);

		srx->transport.family = AF_INET;

		srx->transport.sin.sin_port = udp_port;

		memcpy(&srx->transport.sin.sin_addr,

		       &ip->daddr.s6_addr32[3], sizeof(struct in_addr));

		break;

	case AF_INET6:

		_net("Rx ICMP6");

		srx->transport.sin.sin_port = udp_port;

		memcpy(&srx->transport.sin6.sin6_addr, &ip->daddr,

		       sizeof(struct in6_addr));

		break;

	default:

		WARN_ON_ONCE(1);

		return NULL;

	}



	_net("ICMP {%pISp}", &srx->transport);

	return rxrpc_lookup_peer_rcu(local, srx);

}

#endif /* CONFIG_AF_RXRPC_IPV6 */



/*

 * Handle an error received on the local endpoint as a tunnel.

 */

void rxrpc_encap_err_rcv(struct sock *sk, struct sk_buff *skb, int err,

			 __be16 port, u32 info, u8 *payload)

{

	struct sock_extended_err ee;

	struct sockaddr_rxrpc srx;

	struct rxrpc_local *local;

	struct rxrpc_peer *peer;

	u8 version = ip_hdr(skb)->version;

	u8 type = icmp_hdr(skb)->type;

	u8 code = icmp_hdr(skb)->code;



	rcu_read_lock();

	local = rcu_dereference_sk_user_data(sk);

	if (unlikely(!local)) {

		rcu_read_unlock();

		return;

	}



	rxrpc_new_skb(skb, rxrpc_skb_received);



	switch (ip_hdr(skb)->version) {

	case IPVERSION:

		peer = rxrpc_lookup_peer_icmp_rcu(local, skb, port, &srx);

		break;

#ifdef CONFIG_AF_RXRPC_IPV6

	case 6:

		peer = rxrpc_lookup_peer_icmp6_rcu(local, skb, port, &srx);

		break;

#endif

	default:

		rcu_read_unlock();

		return;

	}



	if (peer && !rxrpc_get_peer_maybe(peer))

		peer = NULL;

	if (!peer) {

		rcu_read_unlock();

		return;

	}



	memset(&ee, 0, sizeof(ee));



	switch (version) {

	case IPVERSION:

		if (type == ICMP_DEST_UNREACH &&

		    code == ICMP_FRAG_NEEDED) {

			rxrpc_adjust_mtu(peer, info);

			rcu_read_unlock();

			rxrpc_put_peer(peer);

			return;

		}



		ee.ee_origin = SO_EE_ORIGIN_ICMP;

		ee.ee_type = type;

		ee.ee_code = code;

		ee.ee_errno = err;

		break;



#ifdef CONFIG_AF_RXRPC_IPV6

	case 6:

		if (type == ICMPV6_PKT_TOOBIG) {

			rxrpc_adjust_mtu(peer, info);

			rcu_read_unlock();

			rxrpc_put_peer(peer);

			return;

		}



		if (err == EACCES)

			err = EHOSTUNREACH;



		ee.ee_origin = SO_EE_ORIGIN_ICMP6;

		ee.ee_type = type;

		ee.ee_code = code;

		ee.ee_errno = err;

		break;

#endif

	}



	trace_rxrpc_rx_icmp(peer, &ee, &srx);



	rxrpc_distribute_error(peer, err, RXRPC_CALL_NETWORK_ERROR);

	rcu_read_unlock();

	rxrpc_put_peer(peer);

}



/*

 * Find the peer associated with a local error.

 */
@@ -246,6 +38,9 @@ static struct rxrpc_peer *rxrpc_lookup_peer_local_rcu(struct rxrpc_local *local, 
	srx->transport_len = local->srx.transport_len;

	srx->transport.family = local->srx.transport.family;



	/* Can we see an ICMP4 packet on an ICMP6 listening socket?  and vice

	 * versa?

	 */

	switch (srx->transport.family) {

	case AF_INET:

		srx->transport_len = sizeof(srx->transport.sin);
@@ -375,20 +170,38 @@ void rxrpc_error_report(struct sock *sk) 
	}

	rxrpc_new_skb(skb, rxrpc_skb_received);

	serr = SKB_EXT_ERR(skb);

	if (!skb->len && serr->ee.ee_origin == SO_EE_ORIGIN_TIMESTAMPING) {

		_leave("UDP empty message");

		rcu_read_unlock();

		rxrpc_free_skb(skb, rxrpc_skb_freed);

		return;

	}



	if (serr->ee.ee_origin == SO_EE_ORIGIN_LOCAL) {

	peer = rxrpc_lookup_peer_local_rcu(local, skb, &srx);

	if (peer && !rxrpc_get_peer_maybe(peer))

		peer = NULL;

		if (peer) {

			trace_rxrpc_rx_icmp(peer, &serr->ee, &srx);

			rxrpc_store_error(peer, serr);

	if (!peer) {

		rcu_read_unlock();

		rxrpc_free_skb(skb, rxrpc_skb_freed);

		_leave(" [no peer]");

		return;

	}



	trace_rxrpc_rx_icmp(peer, &serr->ee, &srx);



	if ((serr->ee.ee_origin == SO_EE_ORIGIN_ICMP &&

	     serr->ee.ee_type == ICMP_DEST_UNREACH &&

	     serr->ee.ee_code == ICMP_FRAG_NEEDED)) {

		rxrpc_adjust_mtu(peer, serr->ee.ee_info);

		goto out;

	}



	rxrpc_store_error(peer, serr);

out:

	rcu_read_unlock();

	rxrpc_free_skb(skb, rxrpc_skb_freed);

	rxrpc_put_peer(peer);



	_leave("");

}