X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=net%2Fbridge%2Fbr_netfilter.c;h=ea3337ad0edcf3b7b19132fc5770ce5e4c90eeb4;hb=refs%2Fheads%2Fvserver;hp=a64272783015c2c909d4bb472d75ac5e7c2b82ca;hpb=4e76c8a9fa413ccc09d3f7f664183dcce3555d57;p=linux-2.6.git diff --git a/net/bridge/br_netfilter.c b/net/bridge/br_netfilter.c index a64272783..ea3337ad0 100644 --- a/net/bridge/br_netfilter.c +++ b/net/bridge/br_netfilter.c @@ -34,13 +34,13 @@ #include #include #include +#include #include #include #include #include -#include #include "br_private.h" #ifdef CONFIG_SYSCTL #include @@ -53,10 +53,10 @@ #ifdef CONFIG_SYSCTL static struct ctl_table_header *brnf_sysctl_header; -static int brnf_call_iptables = 1; -static int brnf_call_ip6tables = 1; -static int brnf_call_arptables = 1; -static int brnf_filter_vlan_tagged = 1; +static int brnf_call_iptables __read_mostly = 1; +static int brnf_call_ip6tables __read_mostly = 1; +static int brnf_call_arptables __read_mostly = 1; +static int brnf_filter_vlan_tagged __read_mostly = 1; #else #define brnf_filter_vlan_tagged 1 #endif @@ -124,14 +124,37 @@ static inline struct nf_bridge_info *nf_bridge_alloc(struct sk_buff *skb) static inline void nf_bridge_save_header(struct sk_buff *skb) { - int header_size = 16; + int header_size = ETH_HLEN; if (skb->protocol == htons(ETH_P_8021Q)) - header_size = 18; + header_size += VLAN_HLEN; memcpy(skb->nf_bridge->data, skb->data - header_size, header_size); } +/* + * When forwarding bridge frames, we save a copy of the original + * header before processing. + */ +int nf_bridge_copy_header(struct sk_buff *skb) +{ + int err; + int header_size = ETH_HLEN; + + if (skb->protocol == htons(ETH_P_8021Q)) + header_size += VLAN_HLEN; + + err = skb_cow(skb, header_size); + if (err) + return err; + + memcpy(skb->data - header_size, skb->nf_bridge->data, header_size); + + if (skb->protocol == htons(ETH_P_8021Q)) + __skb_push(skb, VLAN_HLEN); + return 0; +} + /* PF_BRIDGE/PRE_ROUTING *********************************************/ /* Undo the changes made for ip6tables PREROUTING and continue the * bridge PRE_ROUTING hook. */ @@ -196,10 +219,14 @@ static void __br_dnat_complain(void) * * Otherwise, the packet is considered to be routed and we just * change the destination MAC address so that the packet will - * later be passed up to the IP stack to be routed. + * later be passed up to the IP stack to be routed. For a redirected + * packet, ip_route_input() will give back the localhost as output device, + * which differs from the bridge device. * * Let us now consider the case that ip_route_input() fails: * + * This can be because the destination address is martian, in which case + * the packet will be dropped. * After a "echo '0' > /proc/sys/net/ipv4/ip_forward" ip_route_input() * will fail, while __ip_route_output_key() will return success. The source * address for __ip_route_output_key() is set to zero, so __ip_route_output_key @@ -212,7 +239,8 @@ static void __br_dnat_complain(void) * * --Lennert, 20020411 * --Bart, 20020416 (updated) - * --Bart, 20021007 (updated) */ + * --Bart, 20021007 (updated) + * --Bart, 20062711 (updated) */ static int br_nf_pre_routing_finish_bridge(struct sk_buff *skb) { if (skb->pkt_type == PACKET_OTHERHOST) { @@ -239,15 +267,15 @@ static int br_nf_pre_routing_finish(struct sk_buff *skb) struct net_device *dev = skb->dev; struct iphdr *iph = skb->nh.iph; struct nf_bridge_info *nf_bridge = skb->nf_bridge; + int err; if (nf_bridge->mask & BRNF_PKT_TYPE) { skb->pkt_type = PACKET_OTHERHOST; nf_bridge->mask ^= BRNF_PKT_TYPE; } nf_bridge->mask ^= BRNF_NF_BRIDGE_PREROUTING; - if (dnat_took_place(skb)) { - if (ip_route_input(skb, iph->daddr, iph->saddr, iph->tos, dev)) { + if ((err = ip_route_input(skb, iph->daddr, iph->saddr, iph->tos, dev))) { struct rtable *rt; struct flowi fl = { .nl_u = { @@ -258,19 +286,33 @@ static int br_nf_pre_routing_finish(struct sk_buff *skb) }, .proto = 0, }; + struct in_device *in_dev = in_dev_get(dev); + + /* If err equals -EHOSTUNREACH the error is due to a + * martian destination or due to the fact that + * forwarding is disabled. For most martian packets, + * ip_route_output_key() will fail. It won't fail for 2 types of + * martian destinations: loopback destinations and destination + * 0.0.0.0. In both cases the packet will be dropped because the + * destination is the loopback device and not the bridge. */ + if (err != -EHOSTUNREACH || !in_dev || IN_DEV_FORWARD(in_dev)) + goto free_skb; if (!ip_route_output_key(&rt, &fl)) { /* - Bridged-and-DNAT'ed traffic doesn't - * require ip_forwarding. - * - Deal with redirected traffic. */ - if (((struct dst_entry *)rt)->dev == dev || - rt->rt_type == RTN_LOCAL) { + * require ip_forwarding. */ + if (((struct dst_entry *)rt)->dev == dev) { skb->dst = (struct dst_entry *)rt; goto bridged_dnat; } + /* we are sure that forwarding is disabled, so printing + * this message is no problem. Note that the packet could + * still have a martian destination address, in which case + * the packet could be dropped even if forwarding were enabled */ __br_dnat_complain(); dst_release((struct dst_entry *)rt); } +free_skb: kfree_skb(skb); return 0; } else { @@ -355,7 +397,7 @@ static int check_hbh_len(struct sk_buff *skb) case IPV6_TLV_JUMBO: if (skb->nh.raw[off + 1] != 4 || (off & 3) != 2) goto bad; - pkt_len = ntohl(*(u32 *) (skb->nh.raw + off + 2)); + pkt_len = ntohl(*(__be32 *) (skb->nh.raw + off + 2)); if (pkt_len <= IPV6_MAXPLEN || skb->nh.ipv6h->payload_len) goto bad; @@ -407,12 +449,8 @@ static unsigned int br_nf_pre_routing_ipv6(unsigned int hook, if (pkt_len || hdr->nexthdr != NEXTHDR_HOP) { if (pkt_len + sizeof(struct ipv6hdr) > skb->len) goto inhdr_error; - if (pkt_len + sizeof(struct ipv6hdr) < skb->len) { - if (__pskb_trim(skb, pkt_len + sizeof(struct ipv6hdr))) - goto inhdr_error; - if (skb->ip_summed == CHECKSUM_HW) - skb->ip_summed = CHECKSUM_NONE; - } + if (pskb_trim_rcsum(skb, pkt_len + sizeof(struct ipv6hdr))) + goto inhdr_error; } if (hdr->nexthdr == NEXTHDR_HOP && check_hbh_len(skb)) goto inhdr_error; @@ -495,11 +533,7 @@ static unsigned int br_nf_pre_routing(unsigned int hook, struct sk_buff **pskb, if (skb->len < len || len < 4 * iph->ihl) goto inhdr_error; - if (skb->len > len) { - __pskb_trim(skb, len); - if (skb->ip_summed == CHECKSUM_HW) - skb->ip_summed = CHECKSUM_NONE; - } + pskb_trim_rcsum(skb, len); nf_bridge_put(skb->nf_bridge); if (!nf_bridge_alloc(skb)) @@ -648,120 +682,50 @@ static unsigned int br_nf_forward_arp(unsigned int hook, struct sk_buff **pskb, return NF_STOLEN; } -/* PF_BRIDGE/LOCAL_OUT ***********************************************/ -static int br_nf_local_out_finish(struct sk_buff *skb) -{ - if (skb->protocol == htons(ETH_P_8021Q)) { - skb_push(skb, VLAN_HLEN); - skb->nh.raw -= VLAN_HLEN; - } - - NF_HOOK_THRESH(PF_BRIDGE, NF_BR_LOCAL_OUT, skb, NULL, skb->dev, - br_forward_finish, NF_BR_PRI_FIRST + 1); - - return 0; -} - -/* This function sees both locally originated IP packets and forwarded +/* PF_BRIDGE/LOCAL_OUT *********************************************** + * + * This function sees both locally originated IP packets and forwarded * IP packets (in both cases the destination device is a bridge * device). It also sees bridged-and-DNAT'ed packets. - * To be able to filter on the physical bridge devices (with the physdev - * module), we steal packets destined to a bridge device away from the - * PF_INET/FORWARD and PF_INET/OUTPUT hook functions, and give them back later, - * when we have determined the real output device. This is done in here. * * If (nf_bridge->mask & BRNF_BRIDGED_DNAT) then the packet is bridged * and we fake the PF_BRIDGE/FORWARD hook. The function br_nf_forward() * will then fake the PF_INET/FORWARD hook. br_nf_local_out() has priority * NF_BR_PRI_FIRST, so no relevant PF_BRIDGE/INPUT functions have been nor * will be executed. - * Otherwise, if nf_bridge->physindev is NULL, the bridge-nf code never touched - * this packet before, and so the packet was locally originated. We fake - * the PF_INET/LOCAL_OUT hook. - * Finally, if nf_bridge->physindev isn't NULL, then the packet was IP routed, - * so we fake the PF_INET/FORWARD hook. ip_sabotage_out() makes sure - * even routed packets that didn't arrive on a bridge interface have their - * nf_bridge->physindev set. */ + */ static unsigned int br_nf_local_out(unsigned int hook, struct sk_buff **pskb, const struct net_device *in, const struct net_device *out, int (*okfn)(struct sk_buff *)) { - struct net_device *realindev, *realoutdev; + struct net_device *realindev; struct sk_buff *skb = *pskb; struct nf_bridge_info *nf_bridge; - int pf; if (!skb->nf_bridge) return NF_ACCEPT; - if (skb->protocol == htons(ETH_P_IP) || IS_VLAN_IP(skb)) - pf = PF_INET; - else - pf = PF_INET6; - -#ifdef CONFIG_NETFILTER_DEBUG - /* Sometimes we get packets with NULL ->dst here (for example, - * running a dhcp client daemon triggers this). This should now - * be fixed, but let's keep the check around. */ - if (skb->dst == NULL) { - printk(KERN_CRIT "br_netfilter: skb->dst == NULL."); - return NF_ACCEPT; - } -#endif - nf_bridge = skb->nf_bridge; - nf_bridge->physoutdev = skb->dev; - realindev = nf_bridge->physindev; + if (!(nf_bridge->mask & BRNF_BRIDGED_DNAT)) + return NF_ACCEPT; /* Bridged, take PF_BRIDGE/FORWARD. * (see big note in front of br_nf_pre_routing_finish) */ - if (nf_bridge->mask & BRNF_BRIDGED_DNAT) { - if (nf_bridge->mask & BRNF_PKT_TYPE) { - skb->pkt_type = PACKET_OTHERHOST; - nf_bridge->mask ^= BRNF_PKT_TYPE; - } - if (skb->protocol == htons(ETH_P_8021Q)) { - skb_push(skb, VLAN_HLEN); - skb->nh.raw -= VLAN_HLEN; - } + nf_bridge->physoutdev = skb->dev; + realindev = nf_bridge->physindev; - NF_HOOK(PF_BRIDGE, NF_BR_FORWARD, skb, realindev, - skb->dev, br_forward_finish); - goto out; + if (nf_bridge->mask & BRNF_PKT_TYPE) { + skb->pkt_type = PACKET_OTHERHOST; + nf_bridge->mask ^= BRNF_PKT_TYPE; } - realoutdev = bridge_parent(skb->dev); - if (!realoutdev) - return NF_DROP; - -#if defined(CONFIG_VLAN_8021Q) || defined(CONFIG_VLAN_8021Q_MODULE) - /* iptables should match -o br0.x */ - if (nf_bridge->netoutdev) - realoutdev = nf_bridge->netoutdev; -#endif if (skb->protocol == htons(ETH_P_8021Q)) { - skb_pull(skb, VLAN_HLEN); - (*pskb)->nh.raw += VLAN_HLEN; - } - /* IP forwarded traffic has a physindev, locally - * generated traffic hasn't. */ - if (realindev != NULL) { - if (!(nf_bridge->mask & BRNF_DONT_TAKE_PARENT)) { - struct net_device *parent = bridge_parent(realindev); - if (parent) - realindev = parent; - } - - NF_HOOK_THRESH(pf, NF_IP_FORWARD, skb, realindev, - realoutdev, br_nf_local_out_finish, - NF_IP_PRI_BRIDGE_SABOTAGE_FORWARD + 1); - } else { - NF_HOOK_THRESH(pf, NF_IP_LOCAL_OUT, skb, realindev, - realoutdev, br_nf_local_out_finish, - NF_IP_PRI_BRIDGE_SABOTAGE_LOCAL_OUT + 1); + skb_push(skb, VLAN_HLEN); + skb->nh.raw -= VLAN_HLEN; } -out: + NF_HOOK(PF_BRIDGE, NF_BR_FORWARD, skb, realindev, skb->dev, + br_forward_finish); return NF_STOLEN; } @@ -791,7 +755,7 @@ static unsigned int br_nf_post_routing(unsigned int hook, struct sk_buff **pskb, * keep the check just to be sure... */ if (skb->mac.raw < skb->head || skb->mac.raw + ETH_HLEN > skb->data) { printk(KERN_CRIT "br_netfilter: Argh!! br_nf_post_routing: " - "bad mac.raw pointer."); + "bad mac.raw pointer.\n"); goto print_error; } #endif @@ -809,7 +773,7 @@ static unsigned int br_nf_post_routing(unsigned int hook, struct sk_buff **pskb, #ifdef CONFIG_NETFILTER_DEBUG if (skb->dst == NULL) { - printk(KERN_CRIT "br_netfilter: skb->dst == NULL."); + printk(KERN_INFO "br_netfilter post_routing: skb->dst == NULL\n"); goto print_error; } #endif @@ -846,6 +810,7 @@ print_error: } printk(" head:%p, raw:%p, data:%p\n", skb->head, skb->mac.raw, skb->data); + dump_stack(); return NF_ACCEPT; #endif } @@ -866,68 +831,6 @@ static unsigned int ip_sabotage_in(unsigned int hook, struct sk_buff **pskb, return NF_ACCEPT; } -/* Postpone execution of PF_INET(6)/FORWARD, PF_INET(6)/LOCAL_OUT - * and PF_INET(6)/POST_ROUTING until we have done the forwarding - * decision in the bridge code and have determined nf_bridge->physoutdev. */ -static unsigned int ip_sabotage_out(unsigned int hook, struct sk_buff **pskb, - const struct net_device *in, - const struct net_device *out, - int (*okfn)(struct sk_buff *)) -{ - struct sk_buff *skb = *pskb; - - if ((out->hard_start_xmit == br_dev_xmit && - okfn != br_nf_forward_finish && - okfn != br_nf_local_out_finish && - okfn != br_nf_dev_queue_xmit) -#if defined(CONFIG_VLAN_8021Q) || defined(CONFIG_VLAN_8021Q_MODULE) - || ((out->priv_flags & IFF_802_1Q_VLAN) && - VLAN_DEV_INFO(out)->real_dev->hard_start_xmit == br_dev_xmit) -#endif - ) { - struct nf_bridge_info *nf_bridge; - - if (!skb->nf_bridge) { -#ifdef CONFIG_SYSCTL - /* This code is executed while in the IP(v6) stack, - the version should be 4 or 6. We can't use - skb->protocol because that isn't set on - PF_INET(6)/LOCAL_OUT. */ - struct iphdr *ip = skb->nh.iph; - - if (ip->version == 4 && !brnf_call_iptables) - return NF_ACCEPT; - else if (ip->version == 6 && !brnf_call_ip6tables) - return NF_ACCEPT; -#endif - if (hook == NF_IP_POST_ROUTING) - return NF_ACCEPT; - if (!nf_bridge_alloc(skb)) - return NF_DROP; - } - - nf_bridge = skb->nf_bridge; - - /* This frame will arrive on PF_BRIDGE/LOCAL_OUT and we - * will need the indev then. For a brouter, the real indev - * can be a bridge port, so we make sure br_nf_local_out() - * doesn't use the bridge parent of the indev by using - * the BRNF_DONT_TAKE_PARENT mask. */ - if (hook == NF_IP_FORWARD && nf_bridge->physindev == NULL) { - nf_bridge->mask |= BRNF_DONT_TAKE_PARENT; - nf_bridge->physindev = (struct net_device *)in; - } -#if defined(CONFIG_VLAN_8021Q) || defined(CONFIG_VLAN_8021Q_MODULE) - /* the iptables outdev is br0.x, not br0 */ - if (out->priv_flags & IFF_802_1Q_VLAN) - nf_bridge->netoutdev = (struct net_device *)out; -#endif - return NF_STOP; - } - - return NF_ACCEPT; -} - /* For br_nf_local_out we need (prio = NF_BR_PRI_FIRST), to insure that innocent * PF_BRIDGE/NF_BR_LOCAL_OUT functions don't get bridged traffic as input. * For br_nf_post_routing, we need (prio = NF_BR_PRI_LAST), because @@ -973,36 +876,6 @@ static struct nf_hook_ops br_nf_ops[] = { .pf = PF_INET6, .hooknum = NF_IP6_PRE_ROUTING, .priority = NF_IP6_PRI_FIRST, }, - { .hook = ip_sabotage_out, - .owner = THIS_MODULE, - .pf = PF_INET, - .hooknum = NF_IP_FORWARD, - .priority = NF_IP_PRI_BRIDGE_SABOTAGE_FORWARD, }, - { .hook = ip_sabotage_out, - .owner = THIS_MODULE, - .pf = PF_INET6, - .hooknum = NF_IP6_FORWARD, - .priority = NF_IP6_PRI_BRIDGE_SABOTAGE_FORWARD, }, - { .hook = ip_sabotage_out, - .owner = THIS_MODULE, - .pf = PF_INET, - .hooknum = NF_IP_LOCAL_OUT, - .priority = NF_IP_PRI_BRIDGE_SABOTAGE_LOCAL_OUT, }, - { .hook = ip_sabotage_out, - .owner = THIS_MODULE, - .pf = PF_INET6, - .hooknum = NF_IP6_LOCAL_OUT, - .priority = NF_IP6_PRI_BRIDGE_SABOTAGE_LOCAL_OUT, }, - { .hook = ip_sabotage_out, - .owner = THIS_MODULE, - .pf = PF_INET, - .hooknum = NF_IP_POST_ROUTING, - .priority = NF_IP_PRI_FIRST, }, - { .hook = ip_sabotage_out, - .owner = THIS_MODULE, - .pf = PF_INET6, - .hooknum = NF_IP6_POST_ROUTING, - .priority = NF_IP6_PRI_FIRST, }, }; #ifdef CONFIG_SYSCTL