From 6869c4d8e066e21623c812c448a05f1ed931c9c6 Mon Sep 17 00:00:00 2001 From: Harald Welte Date: Tue, 9 Aug 2005 19:24:19 -0700 Subject: [PATCH] [NETFILTER]: reduce netfilter sk_buff enlargement As discussed at netconf'05, we're trying to save every bit in sk_buff. The patch below makes sk_buff 8 bytes smaller. I did some basic testing on my notebook and it seems to work. The only real in-tree user of nfcache was IPVS, who only needs a single bit. Unfortunately I couldn't find some other free bit in sk_buff to stuff that bit into, so I introduced a separate field for them. Maybe the IPVS guys can resolve that to further save space. Initially I wanted to shrink pkt_type to three bits (PACKET_HOST and alike are only 6 values defined), but unfortunately the bluetooth code overloads pkt_type :( The conntrack-event-api (out-of-tree) uses nfcache, but Rusty just came up with a way how to do it without any skb fields, so it's safe to remove it. - remove all never-implemented 'nfcache' code - don't have ipvs code abuse 'nfcache' field. currently get's their own compile-conditional skb->ipvs_property field. IPVS maintainers can decide to move this bit elswhere, but nfcache needs to die. - remove skb->nfcache field to save 4 bytes - move skb->nfctinfo into three unused bits to save further 4 bytes Signed-off-by: Harald Welte Signed-off-by: David S. Miller --- include/linux/netfilter.h | 3 +++ include/linux/netfilter_decnet.h | 3 +++ include/linux/netfilter_ipv4.h | 3 +++ include/linux/netfilter_ipv6.h | 3 +++ include/linux/skbuff.h | 10 +++++----- net/bridge/netfilter/ebt_mark.c | 5 ++--- net/core/skbuff.c | 2 -- net/ipv4/ip_output.c | 1 - net/ipv4/ipvs/ip_vs_core.c | 9 +++++---- net/ipv4/ipvs/ip_vs_xmit.c | 2 +- net/ipv4/netfilter/ip_conntrack_core.c | 7 +------ net/ipv4/netfilter/ip_nat_core.c | 1 - net/ipv4/netfilter/ip_nat_standalone.c | 2 -- net/ipv4/netfilter/ip_queue.c | 1 - net/ipv4/netfilter/ip_tables.c | 1 - net/ipv4/netfilter/ipt_CLASSIFY.c | 4 +--- net/ipv4/netfilter/ipt_CONNMARK.c | 4 +--- net/ipv4/netfilter/ipt_DSCP.c | 1 - net/ipv4/netfilter/ipt_ECN.c | 2 -- net/ipv4/netfilter/ipt_MARK.c | 10 ++++------ net/ipv4/netfilter/ipt_REJECT.c | 1 - net/ipv4/netfilter/ipt_TCPMSS.c | 1 - net/ipv4/netfilter/ipt_TOS.c | 1 - net/ipv6/ip6_output.c | 16 ++-------------- net/ipv6/netfilter/ip6_queue.c | 1 - net/ipv6/netfilter/ip6_tables.c | 1 - net/ipv6/netfilter/ip6t_MARK.c | 5 ++--- 27 files changed, 36 insertions(+), 64 deletions(-) diff --git a/include/linux/netfilter.h b/include/linux/netfilter.h index 2e2045482c..ec60856408 100644 --- a/include/linux/netfilter.h +++ b/include/linux/netfilter.h @@ -21,10 +21,13 @@ #define NF_STOP 5 #define NF_MAX_VERDICT NF_STOP +/* only for userspace compatibility */ +#ifndef __KERNEL__ /* Generic cache responses from hook functions. <= 0x2000 is used for protocol-flags. */ #define NFC_UNKNOWN 0x4000 #define NFC_ALTERED 0x8000 +#endif #ifdef __KERNEL__ #include diff --git a/include/linux/netfilter_decnet.h b/include/linux/netfilter_decnet.h index 3064eec9cb..0189794841 100644 --- a/include/linux/netfilter_decnet.h +++ b/include/linux/netfilter_decnet.h @@ -9,6 +9,8 @@ #include +/* only for userspace compatibility */ +#ifndef __KERNEL__ /* IP Cache bits. */ /* Src IP address. */ #define NFC_DN_SRC 0x0001 @@ -18,6 +20,7 @@ #define NFC_DN_IF_IN 0x0004 /* Output device. */ #define NFC_DN_IF_OUT 0x0008 +#endif /* ! __KERNEL__ */ /* DECnet Hooks */ /* After promisc drops, checksum checks. */ diff --git a/include/linux/netfilter_ipv4.h b/include/linux/netfilter_ipv4.h index 3ebc36afae..552815b819 100644 --- a/include/linux/netfilter_ipv4.h +++ b/include/linux/netfilter_ipv4.h @@ -8,6 +8,8 @@ #include #include +/* only for userspace compatibility */ +#ifndef __KERNEL__ /* IP Cache bits. */ /* Src IP address. */ #define NFC_IP_SRC 0x0001 @@ -35,6 +37,7 @@ #define NFC_IP_DST_PT 0x0400 /* Something else about the proto */ #define NFC_IP_PROTO_UNKNOWN 0x2000 +#endif /* ! __KERNEL__ */ /* IP Hooks */ /* After promisc drops, checksum checks. */ diff --git a/include/linux/netfilter_ipv6.h b/include/linux/netfilter_ipv6.h index bee7a5ec7c..20c069a5e4 100644 --- a/include/linux/netfilter_ipv6.h +++ b/include/linux/netfilter_ipv6.h @@ -10,6 +10,8 @@ #include +/* only for userspace compatibility */ +#ifndef __KERNEL__ /* IP Cache bits. */ /* Src IP address. */ #define NFC_IP6_SRC 0x0001 @@ -38,6 +40,7 @@ #define NFC_IP6_DST_PT 0x0400 /* Something else about the proto */ #define NFC_IP6_PROTO_UNKNOWN 0x2000 +#endif /* ! __KERNEL__ */ /* IP6 Hooks */ diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index 2e40f4c9f7..4b929c3c1a 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -190,7 +190,6 @@ struct skb_shared_info { * @end: End pointer * @destructor: Destruct function * @nfmark: Can be used for communication between hooks - * @nfcache: Cache info * @nfct: Associated connection, if any * @nfctinfo: Relationship of this skb to the connection * @nf_bridge: Saved data about a bridged frame - see br_netfilter.c @@ -252,17 +251,18 @@ struct sk_buff { __u8 local_df:1, cloned:1, ip_summed:2, - nohdr:1; - /* 3 bits spare */ + nohdr:1, + nfctinfo:3; __u8 pkt_type; __be16 protocol; void (*destructor)(struct sk_buff *skb); #ifdef CONFIG_NETFILTER __u32 nfmark; - __u32 nfcache; - __u32 nfctinfo; struct nf_conntrack *nfct; +#if defined(CONFIG_IP_VS) || defined(CONFIG_IP_VS_MODULE) + __u8 ipvs_property:1; +#endif #ifdef CONFIG_BRIDGE_NETFILTER struct nf_bridge_info *nf_bridge; #endif diff --git a/net/bridge/netfilter/ebt_mark.c b/net/bridge/netfilter/ebt_mark.c index 02c632b4d3..c93d35ab95 100644 --- a/net/bridge/netfilter/ebt_mark.c +++ b/net/bridge/netfilter/ebt_mark.c @@ -23,10 +23,9 @@ static int ebt_target_mark(struct sk_buff **pskb, unsigned int hooknr, { struct ebt_mark_t_info *info = (struct ebt_mark_t_info *)data; - if ((*pskb)->nfmark != info->mark) { + if ((*pskb)->nfmark != info->mark) (*pskb)->nfmark = info->mark; - (*pskb)->nfcache |= NFC_ALTERED; - } + return info->target; } diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 7eab867ede..096991cb09 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -361,7 +361,6 @@ struct sk_buff *skb_clone(struct sk_buff *skb, unsigned int __nocast gfp_mask) n->destructor = NULL; #ifdef CONFIG_NETFILTER C(nfmark); - C(nfcache); C(nfct); nf_conntrack_get(skb->nfct); C(nfctinfo); @@ -424,7 +423,6 @@ static void copy_skb_header(struct sk_buff *new, const struct sk_buff *old) new->destructor = NULL; #ifdef CONFIG_NETFILTER new->nfmark = old->nfmark; - new->nfcache = old->nfcache; new->nfct = old->nfct; nf_conntrack_get(old->nfct); new->nfctinfo = old->nfctinfo; diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c index 80d13103b2..766564cb42 100644 --- a/net/ipv4/ip_output.c +++ b/net/ipv4/ip_output.c @@ -392,7 +392,6 @@ static void ip_copy_metadata(struct sk_buff *to, struct sk_buff *from) #endif #ifdef CONFIG_NETFILTER to->nfmark = from->nfmark; - to->nfcache = from->nfcache; /* Connection association is same as pre-frag packet */ nf_conntrack_put(to->nfct); to->nfct = from->nfct; diff --git a/net/ipv4/ipvs/ip_vs_core.c b/net/ipv4/ipvs/ip_vs_core.c index 5fb257dd07..3ac7eeca04 100644 --- a/net/ipv4/ipvs/ip_vs_core.c +++ b/net/ipv4/ipvs/ip_vs_core.c @@ -22,6 +22,7 @@ * * Changes: * Paul `Rusty' Russell properly handle non-linear skbs + * Harald Welte don't use nfcache * */ @@ -529,7 +530,7 @@ static unsigned int ip_vs_post_routing(unsigned int hooknum, const struct net_device *out, int (*okfn)(struct sk_buff *)) { - if (!((*pskb)->nfcache & NFC_IPVS_PROPERTY)) + if (!((*pskb)->ipvs_property)) return NF_ACCEPT; /* The packet was sent from IPVS, exit this chain */ @@ -701,7 +702,7 @@ static int ip_vs_out_icmp(struct sk_buff **pskb, int *related) /* do the statistics and put it back */ ip_vs_out_stats(cp, skb); - skb->nfcache |= NFC_IPVS_PROPERTY; + skb->ipvs_property = 1; verdict = NF_ACCEPT; out: @@ -739,7 +740,7 @@ ip_vs_out(unsigned int hooknum, struct sk_buff **pskb, EnterFunction(11); - if (skb->nfcache & NFC_IPVS_PROPERTY) + if (skb->ipvs_property) return NF_ACCEPT; iph = skb->nh.iph; @@ -821,7 +822,7 @@ ip_vs_out(unsigned int hooknum, struct sk_buff **pskb, ip_vs_set_state(cp, IP_VS_DIR_OUTPUT, skb, pp); ip_vs_conn_put(cp); - skb->nfcache |= NFC_IPVS_PROPERTY; + skb->ipvs_property = 1; LeaveFunction(11); return NF_ACCEPT; diff --git a/net/ipv4/ipvs/ip_vs_xmit.c b/net/ipv4/ipvs/ip_vs_xmit.c index a8512a3fd0..3b87482049 100644 --- a/net/ipv4/ipvs/ip_vs_xmit.c +++ b/net/ipv4/ipvs/ip_vs_xmit.c @@ -127,7 +127,7 @@ ip_vs_dst_reset(struct ip_vs_dest *dest) #define IP_VS_XMIT(skb, rt) \ do { \ - (skb)->nfcache |= NFC_IPVS_PROPERTY; \ + (skb)->ipvs_property = 1; \ (skb)->ip_summed = CHECKSUM_NONE; \ NF_HOOK(PF_INET, NF_IP_LOCAL_OUT, (skb), NULL, \ (rt)->u.dst.dev, dst_output); \ diff --git a/net/ipv4/netfilter/ip_conntrack_core.c b/net/ipv4/netfilter/ip_conntrack_core.c index a7f0c821a9..04c3414361 100644 --- a/net/ipv4/netfilter/ip_conntrack_core.c +++ b/net/ipv4/netfilter/ip_conntrack_core.c @@ -625,9 +625,6 @@ unsigned int ip_conntrack_in(unsigned int hooknum, return NF_DROP; } - /* FIXME: Do this right please. --RR */ - (*pskb)->nfcache |= NFC_UNKNOWN; - /* Doesn't cover locally-generated broadcast, so not worth it. */ #if 0 /* Ignore broadcast: no `connection'. */ @@ -943,10 +940,8 @@ ip_ct_gather_frags(struct sk_buff *skb, u_int32_t user) skb = ip_defrag(skb, user); local_bh_enable(); - if (skb) { + if (skb) ip_send_check(skb->nh.iph); - skb->nfcache |= NFC_ALTERED; - } return skb; } diff --git a/net/ipv4/netfilter/ip_nat_core.c b/net/ipv4/netfilter/ip_nat_core.c index 739b6dde1c..ed4d731880 100644 --- a/net/ipv4/netfilter/ip_nat_core.c +++ b/net/ipv4/netfilter/ip_nat_core.c @@ -321,7 +321,6 @@ manip_pkt(u_int16_t proto, { struct iphdr *iph; - (*pskb)->nfcache |= NFC_ALTERED; if (!skb_ip_make_writable(pskb, iphdroff + sizeof(*iph))) return 0; diff --git a/net/ipv4/netfilter/ip_nat_standalone.c b/net/ipv4/netfilter/ip_nat_standalone.c index 91d5ea1dbb..9ecba97903 100644 --- a/net/ipv4/netfilter/ip_nat_standalone.c +++ b/net/ipv4/netfilter/ip_nat_standalone.c @@ -73,8 +73,6 @@ ip_nat_fn(unsigned int hooknum, IP_NF_ASSERT(!((*pskb)->nh.iph->frag_off & htons(IP_MF|IP_OFFSET))); - (*pskb)->nfcache |= NFC_UNKNOWN; - /* If we had a hardware checksum before, it's now invalid */ if ((*pskb)->ip_summed == CHECKSUM_HW) if (skb_checksum_help(*pskb, (out == NULL))) diff --git a/net/ipv4/netfilter/ip_queue.c b/net/ipv4/netfilter/ip_queue.c index c6baa81743..bc0af8d8e9 100644 --- a/net/ipv4/netfilter/ip_queue.c +++ b/net/ipv4/netfilter/ip_queue.c @@ -392,7 +392,6 @@ ipq_mangle_ipv4(ipq_verdict_msg_t *v, struct ipq_queue_entry *e) return -ENOMEM; memcpy(e->skb->data, v->payload, v->data_len); e->skb->ip_summed = CHECKSUM_NONE; - e->skb->nfcache |= NFC_ALTERED; /* * Extra routing may needed on local out, as the QUEUE target never diff --git a/net/ipv4/netfilter/ip_tables.c b/net/ipv4/netfilter/ip_tables.c index c88dfcd38c..ff8d85d207 100644 --- a/net/ipv4/netfilter/ip_tables.c +++ b/net/ipv4/netfilter/ip_tables.c @@ -312,7 +312,6 @@ ipt_do_table(struct sk_buff **pskb, do { IP_NF_ASSERT(e); IP_NF_ASSERT(back); - (*pskb)->nfcache |= e->nfcache; if (ip_packet_match(ip, indev, outdev, &e->ip, offset)) { struct ipt_entry_target *t; diff --git a/net/ipv4/netfilter/ipt_CLASSIFY.c b/net/ipv4/netfilter/ipt_CLASSIFY.c index 9842e6e231..dab78d8bd4 100644 --- a/net/ipv4/netfilter/ipt_CLASSIFY.c +++ b/net/ipv4/netfilter/ipt_CLASSIFY.c @@ -32,10 +32,8 @@ target(struct sk_buff **pskb, { const struct ipt_classify_target_info *clinfo = targinfo; - if((*pskb)->priority != clinfo->priority) { + if((*pskb)->priority != clinfo->priority) (*pskb)->priority = clinfo->priority; - (*pskb)->nfcache |= NFC_ALTERED; - } return IPT_CONTINUE; } diff --git a/net/ipv4/netfilter/ipt_CONNMARK.c b/net/ipv4/netfilter/ipt_CONNMARK.c index 8ed744157b..1346380213 100644 --- a/net/ipv4/netfilter/ipt_CONNMARK.c +++ b/net/ipv4/netfilter/ipt_CONNMARK.c @@ -61,10 +61,8 @@ target(struct sk_buff **pskb, case IPT_CONNMARK_RESTORE: nfmark = (*pskb)->nfmark; diff = (ct->mark ^ nfmark) & markinfo->mask; - if (diff != 0) { + if (diff != 0) (*pskb)->nfmark = nfmark ^ diff; - (*pskb)->nfcache |= NFC_ALTERED; - } break; } } diff --git a/net/ipv4/netfilter/ipt_DSCP.c b/net/ipv4/netfilter/ipt_DSCP.c index 3ea4509099..975476fef2 100644 --- a/net/ipv4/netfilter/ipt_DSCP.c +++ b/net/ipv4/netfilter/ipt_DSCP.c @@ -51,7 +51,6 @@ target(struct sk_buff **pskb, sizeof(diffs), (*pskb)->nh.iph->check ^ 0xFFFF)); - (*pskb)->nfcache |= NFC_ALTERED; } return IPT_CONTINUE; } diff --git a/net/ipv4/netfilter/ipt_ECN.c b/net/ipv4/netfilter/ipt_ECN.c index 94a0ce1c1c..f63a9bc0e4 100644 --- a/net/ipv4/netfilter/ipt_ECN.c +++ b/net/ipv4/netfilter/ipt_ECN.c @@ -43,7 +43,6 @@ set_ect_ip(struct sk_buff **pskb, const struct ipt_ECN_info *einfo) sizeof(diffs), (*pskb)->nh.iph->check ^0xFFFF)); - (*pskb)->nfcache |= NFC_ALTERED; } return 1; } @@ -87,7 +86,6 @@ set_ect_tcp(struct sk_buff **pskb, const struct ipt_ECN_info *einfo, int inward) tcph->check = csum_fold(csum_partial((char *)diffs, sizeof(diffs), tcph->check^0xFFFF)); - (*pskb)->nfcache |= NFC_ALTERED; return 1; } diff --git a/net/ipv4/netfilter/ipt_MARK.c b/net/ipv4/netfilter/ipt_MARK.c index 8526398346..52b4f2c296 100644 --- a/net/ipv4/netfilter/ipt_MARK.c +++ b/net/ipv4/netfilter/ipt_MARK.c @@ -29,10 +29,9 @@ target_v0(struct sk_buff **pskb, { const struct ipt_mark_target_info *markinfo = targinfo; - if((*pskb)->nfmark != markinfo->mark) { + if((*pskb)->nfmark != markinfo->mark) (*pskb)->nfmark = markinfo->mark; - (*pskb)->nfcache |= NFC_ALTERED; - } + return IPT_CONTINUE; } @@ -61,10 +60,9 @@ target_v1(struct sk_buff **pskb, break; } - if((*pskb)->nfmark != mark) { + if((*pskb)->nfmark != mark) (*pskb)->nfmark = mark; - (*pskb)->nfcache |= NFC_ALTERED; - } + return IPT_CONTINUE; } diff --git a/net/ipv4/netfilter/ipt_REJECT.c b/net/ipv4/netfilter/ipt_REJECT.c index 9156964460..f115a84a4a 100644 --- a/net/ipv4/netfilter/ipt_REJECT.c +++ b/net/ipv4/netfilter/ipt_REJECT.c @@ -156,7 +156,6 @@ static void send_reset(struct sk_buff *oldskb, int hook) /* This packet will not be the same as the other: clear nf fields */ nf_reset(nskb); - nskb->nfcache = 0; nskb->nfmark = 0; #ifdef CONFIG_BRIDGE_NETFILTER nf_bridge_put(nskb->nf_bridge); diff --git a/net/ipv4/netfilter/ipt_TCPMSS.c b/net/ipv4/netfilter/ipt_TCPMSS.c index 7b84a25444..949288319c 100644 --- a/net/ipv4/netfilter/ipt_TCPMSS.c +++ b/net/ipv4/netfilter/ipt_TCPMSS.c @@ -190,7 +190,6 @@ ipt_tcpmss_target(struct sk_buff **pskb, newmss); retmodified: - (*pskb)->nfcache |= NFC_UNKNOWN | NFC_ALTERED; return IPT_CONTINUE; } diff --git a/net/ipv4/netfilter/ipt_TOS.c b/net/ipv4/netfilter/ipt_TOS.c index 85c70d240f..49abb7eef0 100644 --- a/net/ipv4/netfilter/ipt_TOS.c +++ b/net/ipv4/netfilter/ipt_TOS.c @@ -46,7 +46,6 @@ target(struct sk_buff **pskb, sizeof(diffs), (*pskb)->nh.iph->check ^0xFFFF)); - (*pskb)->nfcache |= NFC_ALTERED; } return IPT_CONTINUE; } diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c index ae652ca14b..590d2b7971 100644 --- a/net/ipv6/ip6_output.c +++ b/net/ipv6/ip6_output.c @@ -185,19 +185,6 @@ int ip6_route_me_harder(struct sk_buff *skb) } #endif -static inline int ip6_maybe_reroute(struct sk_buff *skb) -{ -#ifdef CONFIG_NETFILTER - if (skb->nfcache & NFC_ALTERED){ - if (ip6_route_me_harder(skb) != 0){ - kfree_skb(skb); - return -EINVAL; - } - } -#endif /* CONFIG_NETFILTER */ - return dst_output(skb); -} - /* * xmit an sk_buff (used by TCP) */ @@ -266,7 +253,8 @@ int ip6_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl, mtu = dst_mtu(dst); if ((skb->len <= mtu) || ipfragok) { IP6_INC_STATS(IPSTATS_MIB_OUTREQUESTS); - return NF_HOOK(PF_INET6, NF_IP6_LOCAL_OUT, skb, NULL, dst->dev, ip6_maybe_reroute); + return NF_HOOK(PF_INET6, NF_IP6_LOCAL_OUT, skb, NULL, dst->dev, + dst_output); } if (net_ratelimit()) diff --git a/net/ipv6/netfilter/ip6_queue.c b/net/ipv6/netfilter/ip6_queue.c index a16df5b27c..83ccedceed 100644 --- a/net/ipv6/netfilter/ip6_queue.c +++ b/net/ipv6/netfilter/ip6_queue.c @@ -388,7 +388,6 @@ ipq_mangle_ipv6(ipq_verdict_msg_t *v, struct ipq_queue_entry *e) return -ENOMEM; memcpy(e->skb->data, v->payload, v->data_len); e->skb->ip_summed = CHECKSUM_NONE; - e->skb->nfcache |= NFC_ALTERED; /* * Extra routing may needed on local out, as the QUEUE target never diff --git a/net/ipv6/netfilter/ip6_tables.c b/net/ipv6/netfilter/ip6_tables.c index 73034511c8..41a67cf6e3 100644 --- a/net/ipv6/netfilter/ip6_tables.c +++ b/net/ipv6/netfilter/ip6_tables.c @@ -401,7 +401,6 @@ ip6t_do_table(struct sk_buff **pskb, do { IP_NF_ASSERT(e); IP_NF_ASSERT(back); - (*pskb)->nfcache |= e->nfcache; if (ip6_packet_match(*pskb, indev, outdev, &e->ipv6, &protoff, &offset)) { struct ip6t_entry_target *t; diff --git a/net/ipv6/netfilter/ip6t_MARK.c b/net/ipv6/netfilter/ip6t_MARK.c index d09ceb0501..81924fcc58 100644 --- a/net/ipv6/netfilter/ip6t_MARK.c +++ b/net/ipv6/netfilter/ip6t_MARK.c @@ -28,10 +28,9 @@ target(struct sk_buff **pskb, { const struct ip6t_mark_target_info *markinfo = targinfo; - if((*pskb)->nfmark != markinfo->mark) { + if((*pskb)->nfmark != markinfo->mark) (*pskb)->nfmark = markinfo->mark; - (*pskb)->nfcache |= NFC_ALTERED; - } + return IP6T_CONTINUE; } -- 2.39.5