This commit was manufactured by cvs2svn to create branch 'vserver'.

[linux-2.6.git] / net / ipv4 / netfilter / nf_nat_proto_icmp.c

diff --git a/net/ipv4/netfilter/nf_nat_proto_icmp.c b/net/ipv4/netfilter/nf_nat_proto_icmp.c
new file mode 100644 (file)
index 0000000..b93c78a
--- /dev/null
+++ b/net/ipv4/netfilter/nf_nat_proto_icmp.c
@@ -0,0 +1,85 @@
+/* (C) 1999-2001 Paul `Rusty' Russell
+ * (C) 2002-2006 Netfilter Core Team <coreteam@netfilter.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/types.h>
+#include <linux/init.h>
+#include <linux/ip.h>
+#include <linux/icmp.h>
+
+#include <linux/netfilter.h>
+#include <net/netfilter/nf_nat.h>
+#include <net/netfilter/nf_nat_core.h>
+#include <net/netfilter/nf_nat_rule.h>
+#include <net/netfilter/nf_nat_protocol.h>
+
+static int
+icmp_in_range(const struct nf_conntrack_tuple *tuple,
+             enum nf_nat_manip_type maniptype,
+             const union nf_conntrack_man_proto *min,
+             const union nf_conntrack_man_proto *max)
+{
+       return ntohs(tuple->src.u.icmp.id) >= ntohs(min->icmp.id) &&
+              ntohs(tuple->src.u.icmp.id) <= ntohs(max->icmp.id);
+}
+
+static int
+icmp_unique_tuple(struct nf_conntrack_tuple *tuple,
+                 const struct nf_nat_range *range,
+                 enum nf_nat_manip_type maniptype,
+                 const struct nf_conn *ct)
+{
+       static u_int16_t id;
+       unsigned int range_size;
+       unsigned int i;
+
+       range_size = ntohs(range->max.icmp.id) - ntohs(range->min.icmp.id) + 1;
+       /* If no range specified... */
+       if (!(range->flags & IP_NAT_RANGE_PROTO_SPECIFIED))
+               range_size = 0xFFFF;
+
+       for (i = 0; i < range_size; i++, id++) {
+               tuple->src.u.icmp.id = htons(ntohs(range->min.icmp.id) +
+                                            (id % range_size));
+               if (!nf_nat_used_tuple(tuple, ct))
+                       return 1;
+       }
+       return 0;
+}
+
+static int
+icmp_manip_pkt(struct sk_buff **pskb,
+              unsigned int iphdroff,
+              const struct nf_conntrack_tuple *tuple,
+              enum nf_nat_manip_type maniptype)
+{
+       struct iphdr *iph = (struct iphdr *)((*pskb)->data + iphdroff);
+       struct icmphdr *hdr;
+       unsigned int hdroff = iphdroff + iph->ihl*4;
+
+       if (!skb_make_writable(pskb, hdroff + sizeof(*hdr)))
+               return 0;
+
+       hdr = (struct icmphdr *)((*pskb)->data + hdroff);
+       nf_proto_csum_replace2(&hdr->checksum, *pskb,
+                              hdr->un.echo.id, tuple->src.u.icmp.id, 0);
+       hdr->un.echo.id = tuple->src.u.icmp.id;
+       return 1;
+}
+
+struct nf_nat_protocol nf_nat_protocol_icmp = {
+       .name                   = "ICMP",
+       .protonum               = IPPROTO_ICMP,
+       .me                     = THIS_MODULE,
+       .manip_pkt              = icmp_manip_pkt,
+       .in_range               = icmp_in_range,
+       .unique_tuple           = icmp_unique_tuple,
+#if defined(CONFIG_NF_CT_NETLINK) || defined(CONFIG_NF_CT_NETLINK_MODULE)
+       .range_to_nfattr        = nf_nat_port_range_to_nfattr,
+       .nfattr_to_range        = nf_nat_port_nfattr_to_range,
+#endif
+};