linux/net/ipv4
Ilpo Järvinen b1879204dd ipmr: merge common code
Also removes redundant skb->len < x check which can't
be true once pskb_may_pull(skb, x) succeeded.

$ diff-funcs pim_rcv ipmr.c ipmr.c pim_rcv_v1
  --- ipmr.c:pim_rcv()
  +++ ipmr.c:pim_rcv_v1()
@@ -1,22 +1,27 @@
-static int pim_rcv(struct sk_buff * skb)
+int pim_rcv_v1(struct sk_buff * skb)
 {
-	struct pimreghdr *pim;
+	struct igmphdr *pim;
 	struct iphdr   *encap;
 	struct net_device  *reg_dev = NULL;

 	if (!pskb_may_pull(skb, sizeof(*pim) + sizeof(*encap)))
 		goto drop;

-	pim = (struct pimreghdr *)skb_transport_header(skb);
-	if (pim->type != ((PIM_VERSION<<4)|(PIM_REGISTER)) ||
-	    (pim->flags&PIM_NULL_REGISTER) ||
-	    (ip_compute_csum((void *)pim, sizeof(*pim)) != 0 &&
-	     csum_fold(skb_checksum(skb, 0, skb->len, 0))))
+	pim = igmp_hdr(skb);
+
+	if (!mroute_do_pim ||
+	    skb->len < sizeof(*pim) + sizeof(*encap) ||
+	    pim->group != PIM_V1_VERSION || pim->code != PIM_V1_REGISTER)
 		goto drop;

-	/* check if the inner packet is destined to mcast group */
 	encap = (struct iphdr *)(skb_transport_header(skb) +
-				 sizeof(struct pimreghdr));
+				 sizeof(struct igmphdr));
+	/*
+	   Check that:
+	   a. packet is really destinted to a multicast group
+	   b. packet is not a NULL-REGISTER
+	   c. packet is not truncated
+	 */
 	if (!ipv4_is_multicast(encap->daddr) ||
 	    encap->tot_len == 0 ||
 	    ntohs(encap->tot_len) + sizeof(*pim) > skb->len)
@@ -40,9 +45,9 @@
 	skb->ip_summed = 0;
 	skb->pkt_type = PACKET_HOST;
 	dst_release(skb->dst);
+	skb->dst = NULL;
 	reg_dev->stats.rx_bytes += skb->len;
 	reg_dev->stats.rx_packets++;
-	skb->dst = NULL;
 	nf_reset(skb);
 	netif_rx(skb);
 	dev_put(reg_dev);

$ codiff net/ipv4/ipmr.o.old net/ipv4/ipmr.o.new

net/ipv4/ipmr.c:
  pim_rcv_v1 | -283
  pim_rcv    | -284
 2 functions changed, 567 bytes removed

net/ipv4/ipmr.c:
  __pim_rcv | +307
 1 function changed, 307 bytes added

net/ipv4/ipmr.o.new:
 3 functions changed, 307 bytes added, 567 bytes removed, diff: -260

(Tested on x86_64).

It seems that pimlen arg could be left out as well and
eq-sizedness of structs trapped with BUILD_BUG_ON but
I don't think that's more than a cosmetic flaw since there
aren't that many args anyway.

Compile tested.

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-12-16 01:15:11 -08:00
..
netfilter Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 2008-12-15 20:03:50 -08:00
af_inet.c tcp: Add GRO support 2008-12-15 23:43:36 -08:00
ah4.c netns xfrm: AH/ESP in netns! 2008-11-25 17:59:27 -08:00
arp.c ipv4: Fix ARP behavior with many mac-vlans 2008-11-16 19:19:38 -08:00
cipso_ipv4.c Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 2008-10-31 00:17:34 -07:00
datagram.c mib: add net to IP_INC_STATS_BH 2008-07-16 20:20:11 -07:00
devinet.c net: clean up net/ipv4/devinet.c 2008-11-03 02:48:48 -08:00
esp4.c netns xfrm: AH/ESP in netns! 2008-11-25 17:59:27 -08:00
fib_frontend.c net: clean up net/ipv4/fib_frontend.c fib_hash.c ip_gre.c 2008-11-03 00:25:16 -08:00
fib_hash.c net: clean up net/ipv4/fib_frontend.c fib_hash.c ip_gre.c 2008-11-03 00:25:16 -08:00
fib_lookup.h [IPV4] FIB_HASH: Reduce memory needs and speedup lookups 2008-01-28 15:02:46 -08:00
fib_rules.c net: add fib_rules_ops to flush_cache method 2008-07-05 19:01:28 -07:00
fib_semantics.c net: clean up net/ipv4/ah4.c esp4.c fib_semantics.c inet_connection_sock.c inetpeer.c ip_output.c 2008-11-03 00:23:42 -08:00
fib_trie.c net: replace NIPQUAD() in net/ipv4/ net/ipv6/ 2008-10-31 00:53:57 -07:00
icmp.c netns xfrm: lookup in netns 2008-11-25 17:35:18 -08:00
igmp.c net: clean up net/ipv4/igmp.c 2008-11-03 00:26:09 -08:00
inet_connection_sock.c icsk: join error paths using goto 2008-12-14 23:13:08 -08:00
inet_diag.c net: Convert TCP/DCCP listening hash tables to use RCU 2008-11-23 17:22:55 -08:00
inet_fragment.c net: convert BUG_TRAP to generic WARN_ON 2008-07-25 21:43:18 -07:00
inet_hashtables.c net: Make sure BHs are disabled in sock_prot_inuse_add() 2008-11-24 00:09:29 -08:00
inet_lro.c include/net net/ - csum_partial - remove unnecessary casts 2008-11-19 15:44:53 -08:00
inet_timewait_sock.c net: convert TCP/DCCP ehash rwlocks to spinlocks 2008-11-20 20:39:09 -08:00
inetpeer.c net: clean up net/ipv4/ah4.c esp4.c fib_semantics.c inet_connection_sock.c inetpeer.c ip_output.c 2008-11-03 00:23:42 -08:00
ip_forward.c net: reduce structures when XFRM=n 2008-10-28 13:24:06 -07:00
ip_fragment.c net: '&' redux 2008-11-03 18:21:05 -08:00
ip_gre.c net: fix tunnels in netns after ndo_ changes 2008-11-23 17:26:26 -08:00
ip_input.c Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 2008-11-18 23:38:23 -08:00
ip_options.c cipso: Add support for native local labeling and fixup mapping names 2008-10-10 10:16:34 -04:00
ip_output.c net: avoid a pair of dst_hold()/dst_release() in ip_push_pending_frames() 2008-11-24 16:07:50 -08:00
ip_sockglue.c net: ip_sockglue.c add static, annotate ports' endianness 2008-11-20 01:54:27 -08:00
ipcomp.c netns xfrm: state lookup in netns 2008-11-25 17:30:50 -08:00
ipconfig.c net: replace NIPQUAD() in net/ipv4/ net/ipv6/ 2008-10-31 00:53:57 -07:00
ipip.c net: fix tunnels in netns after ndo_ changes 2008-11-23 17:26:26 -08:00
ipmr.c ipmr: merge common code 2008-12-16 01:15:11 -08:00
Kconfig IPVS: Move IPVS to net/netfilter/ipvs 2008-10-07 08:38:24 +11:00
Makefile IPVS: Move IPVS to net/netfilter/ipvs 2008-10-07 08:38:24 +11:00
netfilter.c Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/kaber/nf-next-2.6 2008-11-28 02:19:15 -08:00
proc.c net: Use a percpu_counter for orphan_count 2008-11-25 21:17:14 -08:00
protocol.c net: remove CVS keywords 2008-06-11 21:00:38 -07:00
raw.c net: avoid a pair of dst_hold()/dst_release() in ip_append_data() 2008-11-24 15:52:46 -08:00
route.c netns xfrm: lookup in netns 2008-11-25 17:35:18 -08:00
syncookies.c tcp: Port redirection support for TCP 2008-10-01 07:46:49 -07:00
sysctl_net_ipv4.c net: '&' redux 2008-11-03 18:21:05 -08:00
tcp_bic.c [TCP]: BIC web page link is corrected. 2008-02-28 22:14:32 -08:00
tcp_cong.c net: Remove CONFIG_KMOD from net/ (towards removing CONFIG_KMOD entirely) 2008-10-16 15:24:51 -07:00
tcp_cubic.c [TCP] CUBIC v2.3 2008-11-02 00:28:10 -07:00
tcp_diag.c net: inet_diag_handler structs can be const 2008-11-19 15:43:27 -08:00
tcp_highspeed.c [TCP]: Cong.ctrl modules: remove unused good_ack from cong_avoid 2008-01-28 14:55:41 -08:00
tcp_htcp.c tcp_htcp: last_cong bug fix 2008-11-12 01:41:09 -08:00
tcp_hybla.c tcp: Fix tcp_hybla zero congestion window growth with small rho and large cwnd. 2008-10-07 15:58:17 -07:00
tcp_illinois.c [TCP]: Cong.ctrl modules: remove unused good_ack from cong_avoid 2008-01-28 14:55:41 -08:00
tcp_input.c tcp: share code through function, not through copy-paste. :-) 2008-12-05 22:43:26 -08:00
tcp_ipv4.c tcp: Add GRO support 2008-12-15 23:43:36 -08:00
tcp_lp.c [TCP]: Cong.ctrl modules: remove unused good_ack from cong_avoid 2008-01-28 14:55:41 -08:00
tcp_minisocks.c net: clean up net/ipv4/ipip.c raw.c tcp.c tcp_minisocks.c tcp_yeah.c xfrm4_policy.c 2008-11-03 00:24:34 -08:00
tcp_output.c tcp: fix tso_should_defer in 64bit 2008-12-05 22:56:07 -08:00
tcp_probe.c net: replace NIPQUAD() in net/ipv4/ net/ipv6/ 2008-10-31 00:53:57 -07:00
tcp_scalable.c [TCP]: Cong.ctrl modules: remove unused good_ack from cong_avoid 2008-01-28 14:55:41 -08:00
tcp_timer.c net: Use a percpu_counter for orphan_count 2008-11-25 21:17:14 -08:00
tcp_vegas.c tcp: tcp_vegas cong avoid fix 2008-12-09 00:13:04 -08:00
tcp_vegas.h [TCP]: congestion control API pass RTT in microseconds 2007-07-31 02:27:57 -07:00
tcp_veno.c net: fix returning void-valued expression warnings 2008-05-01 02:47:38 -07:00
tcp_westwood.c [TCP]: congestion control API pass RTT in microseconds 2007-07-31 02:27:57 -07:00
tcp_yeah.c net: clean up net/ipv4/ipip.c raw.c tcp.c tcp_minisocks.c tcp_yeah.c xfrm4_policy.c 2008-11-03 00:24:34 -08:00
tcp.c tcp: Add GRO support 2008-12-15 23:43:36 -08:00
tunnel4.c [IPV4] TUNNEL4: Fix incoming packet length check for inter-protocol tunnel. 2008-06-05 04:02:33 +09:00
udp_impl.h udp: introduce struct udp_table and multiple spinlocks 2008-10-29 01:41:45 -07:00
udp.c net: udp_unhash() can test if sk is hashed 2008-11-25 13:55:15 -08:00
udplite.c udp: RCU handling for Unicast packets. 2008-10-29 02:11:14 -07:00
xfrm4_input.c [IPSEC]: Fix transport-mode async resume on intput without netfilter 2008-01-28 15:00:10 -08:00
xfrm4_mode_beet.c ipsec: Interfamily IPSec BEET 2008-08-06 02:39:30 -07:00
xfrm4_mode_transport.c [IPSEC]: Use IPv6 calling convention as the convention for x->mode->output 2007-10-10 16:55:54 -07:00
xfrm4_mode_tunnel.c xfrm: fix fragmentation for ipv4 xfrm tunnel 2008-06-17 16:38:23 -07:00
xfrm4_output.c [IPSEC]: Fix inter address family IPsec tunnel handling. 2008-03-24 14:51:51 -07:00
xfrm4_policy.c netns xfrm: ->get_saddr in netns 2008-11-25 17:56:49 -08:00
xfrm4_state.c xfrm: remove useless forward declarations 2008-11-25 01:05:54 -08:00
xfrm4_tunnel.c [IPCOMP]: Fix reception of incompressible packets 2008-01-31 19:27:24 -08:00