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-rw-r--r--net/ipv6/netfilter/ip6t_REJECT.c179
1 files changed, 8 insertions, 171 deletions
diff --git a/net/ipv6/netfilter/ip6t_REJECT.c b/net/ipv6/netfilter/ip6t_REJECT.c
index da00a2ecde55..544b0a9da1b5 100644
--- a/net/ipv6/netfilter/ip6t_REJECT.c
+++ b/net/ipv6/netfilter/ip6t_REJECT.c
@@ -23,181 +23,18 @@
#include <linux/skbuff.h>
#include <linux/icmpv6.h>
#include <linux/netdevice.h>
-#include <net/ipv6.h>
-#include <net/tcp.h>
#include <net/icmp.h>
-#include <net/ip6_checksum.h>
-#include <net/ip6_fib.h>
-#include <net/ip6_route.h>
#include <net/flow.h>
#include <linux/netfilter/x_tables.h>
#include <linux/netfilter_ipv6/ip6_tables.h>
#include <linux/netfilter_ipv6/ip6t_REJECT.h>
+#include <net/netfilter/ipv6/nf_reject.h>
+
MODULE_AUTHOR("Yasuyuki KOZAKAI <yasuyuki.kozakai@toshiba.co.jp>");
MODULE_DESCRIPTION("Xtables: packet \"rejection\" target for IPv6");
MODULE_LICENSE("GPL");
-/* Send RST reply */
-static void send_reset(struct net *net, struct sk_buff *oldskb, int hook)
-{
- struct sk_buff *nskb;
- struct tcphdr otcph, *tcph;
- unsigned int otcplen, hh_len;
- int tcphoff, needs_ack;
- const struct ipv6hdr *oip6h = ipv6_hdr(oldskb);
- struct ipv6hdr *ip6h;
-#define DEFAULT_TOS_VALUE 0x0U
- const __u8 tclass = DEFAULT_TOS_VALUE;
- struct dst_entry *dst = NULL;
- u8 proto;
- __be16 frag_off;
- struct flowi6 fl6;
-
- if ((!(ipv6_addr_type(&oip6h->saddr) & IPV6_ADDR_UNICAST)) ||
- (!(ipv6_addr_type(&oip6h->daddr) & IPV6_ADDR_UNICAST))) {
- pr_debug("addr is not unicast.\n");
- return;
- }
-
- proto = oip6h->nexthdr;
- tcphoff = ipv6_skip_exthdr(oldskb, ((u8*)(oip6h+1) - oldskb->data), &proto, &frag_off);
-
- if ((tcphoff < 0) || (tcphoff > oldskb->len)) {
- pr_debug("Cannot get TCP header.\n");
- return;
- }
-
- otcplen = oldskb->len - tcphoff;
-
- /* IP header checks: fragment, too short. */
- if (proto != IPPROTO_TCP || otcplen < sizeof(struct tcphdr)) {
- pr_debug("proto(%d) != IPPROTO_TCP, "
- "or too short. otcplen = %d\n",
- proto, otcplen);
- return;
- }
-
- if (skb_copy_bits(oldskb, tcphoff, &otcph, sizeof(struct tcphdr)))
- BUG();
-
- /* No RST for RST. */
- if (otcph.rst) {
- pr_debug("RST is set\n");
- return;
- }
-
- /* Check checksum. */
- if (nf_ip6_checksum(oldskb, hook, tcphoff, IPPROTO_TCP)) {
- pr_debug("TCP checksum is invalid\n");
- return;
- }
-
- memset(&fl6, 0, sizeof(fl6));
- fl6.flowi6_proto = IPPROTO_TCP;
- fl6.saddr = oip6h->daddr;
- fl6.daddr = oip6h->saddr;
- fl6.fl6_sport = otcph.dest;
- fl6.fl6_dport = otcph.source;
- security_skb_classify_flow(oldskb, flowi6_to_flowi(&fl6));
- dst = ip6_route_output(net, NULL, &fl6);
- if (dst == NULL || dst->error) {
- dst_release(dst);
- return;
- }
- dst = xfrm_lookup(net, dst, flowi6_to_flowi(&fl6), NULL, 0);
- if (IS_ERR(dst))
- return;
-
- hh_len = (dst->dev->hard_header_len + 15)&~15;
- nskb = alloc_skb(hh_len + 15 + dst->header_len + sizeof(struct ipv6hdr)
- + sizeof(struct tcphdr) + dst->trailer_len,
- GFP_ATOMIC);
-
- if (!nskb) {
- net_dbg_ratelimited("cannot alloc skb\n");
- dst_release(dst);
- return;
- }
-
- skb_dst_set(nskb, dst);
-
- skb_reserve(nskb, hh_len + dst->header_len);
-
- skb_put(nskb, sizeof(struct ipv6hdr));
- skb_reset_network_header(nskb);
- ip6h = ipv6_hdr(nskb);
- ip6_flow_hdr(ip6h, tclass, 0);
- ip6h->hop_limit = ip6_dst_hoplimit(dst);
- ip6h->nexthdr = IPPROTO_TCP;
- ip6h->saddr = oip6h->daddr;
- ip6h->daddr = oip6h->saddr;
-
- skb_reset_transport_header(nskb);
- tcph = (struct tcphdr *)skb_put(nskb, sizeof(struct tcphdr));
- /* Truncate to length (no data) */
- tcph->doff = sizeof(struct tcphdr)/4;
- tcph->source = otcph.dest;
- tcph->dest = otcph.source;
-
- if (otcph.ack) {
- needs_ack = 0;
- tcph->seq = otcph.ack_seq;
- tcph->ack_seq = 0;
- } else {
- needs_ack = 1;
- tcph->ack_seq = htonl(ntohl(otcph.seq) + otcph.syn + otcph.fin
- + otcplen - (otcph.doff<<2));
- tcph->seq = 0;
- }
-
- /* Reset flags */
- ((u_int8_t *)tcph)[13] = 0;
- tcph->rst = 1;
- tcph->ack = needs_ack;
- tcph->window = 0;
- tcph->urg_ptr = 0;
- tcph->check = 0;
-
- /* Adjust TCP checksum */
- tcph->check = csum_ipv6_magic(&ipv6_hdr(nskb)->saddr,
- &ipv6_hdr(nskb)->daddr,
- sizeof(struct tcphdr), IPPROTO_TCP,
- csum_partial(tcph,
- sizeof(struct tcphdr), 0));
-
- nf_ct_attach(nskb, oldskb);
-
-#ifdef CONFIG_BRIDGE_NETFILTER
- /* If we use ip6_local_out for bridged traffic, the MAC source on
- * the RST will be ours, instead of the destination's. This confuses
- * some routers/firewalls, and they drop the packet. So we need to
- * build the eth header using the original destination's MAC as the
- * source, and send the RST packet directly.
- */
- if (oldskb->nf_bridge) {
- struct ethhdr *oeth = eth_hdr(oldskb);
- nskb->dev = oldskb->nf_bridge->physindev;
- nskb->protocol = htons(ETH_P_IPV6);
- ip6h->payload_len = htons(sizeof(struct tcphdr));
- if (dev_hard_header(nskb, nskb->dev, ntohs(nskb->protocol),
- oeth->h_source, oeth->h_dest, nskb->len) < 0)
- return;
- dev_queue_xmit(nskb);
- } else
-#endif
- ip6_local_out(nskb);
-}
-
-static inline void
-send_unreach(struct net *net, struct sk_buff *skb_in, unsigned char code,
- unsigned int hooknum)
-{
- if (hooknum == NF_INET_LOCAL_OUT && skb_in->dev == NULL)
- skb_in->dev = net->loopback_dev;
-
- icmpv6_send(skb_in, ICMPV6_DEST_UNREACH, code, 0);
-}
static unsigned int
reject_tg6(struct sk_buff *skb, const struct xt_action_param *par)
@@ -208,25 +45,25 @@ reject_tg6(struct sk_buff *skb, const struct xt_action_param *par)
pr_debug("%s: medium point\n", __func__);
switch (reject->with) {
case IP6T_ICMP6_NO_ROUTE:
- send_unreach(net, skb, ICMPV6_NOROUTE, par->hooknum);
+ nf_send_unreach6(net, skb, ICMPV6_NOROUTE, par->hooknum);
break;
case IP6T_ICMP6_ADM_PROHIBITED:
- send_unreach(net, skb, ICMPV6_ADM_PROHIBITED, par->hooknum);
+ nf_send_unreach6(net, skb, ICMPV6_ADM_PROHIBITED, par->hooknum);
break;
case IP6T_ICMP6_NOT_NEIGHBOUR:
- send_unreach(net, skb, ICMPV6_NOT_NEIGHBOUR, par->hooknum);
+ nf_send_unreach6(net, skb, ICMPV6_NOT_NEIGHBOUR, par->hooknum);
break;
case IP6T_ICMP6_ADDR_UNREACH:
- send_unreach(net, skb, ICMPV6_ADDR_UNREACH, par->hooknum);
+ nf_send_unreach6(net, skb, ICMPV6_ADDR_UNREACH, par->hooknum);
break;
case IP6T_ICMP6_PORT_UNREACH:
- send_unreach(net, skb, ICMPV6_PORT_UNREACH, par->hooknum);
+ nf_send_unreach6(net, skb, ICMPV6_PORT_UNREACH, par->hooknum);
break;
case IP6T_ICMP6_ECHOREPLY:
/* Do nothing */
break;
case IP6T_TCP_RESET:
- send_reset(net, skb, par->hooknum);
+ nf_send_reset6(net, skb, par->hooknum);
break;
default:
net_info_ratelimited("case %u not handled yet\n", reject->with);