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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /net/ipv4/netfilter/ip_nat_amanda.c
Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'net/ipv4/netfilter/ip_nat_amanda.c')
-rw-r--r--net/ipv4/netfilter/ip_nat_amanda.c88
1 files changed, 88 insertions, 0 deletions
diff --git a/net/ipv4/netfilter/ip_nat_amanda.c b/net/ipv4/netfilter/ip_nat_amanda.c
new file mode 100644
index 00000000000..da1f412583e
--- /dev/null
+++ b/net/ipv4/netfilter/ip_nat_amanda.c
@@ -0,0 +1,88 @@
+/* Amanda extension for TCP NAT alteration.
+ * (C) 2002 by Brian J. Murrell <netfilter@interlinx.bc.ca>
+ * based on a copy of HW's ip_nat_irc.c as well as other modules
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ *
+ * Module load syntax:
+ * insmod ip_nat_amanda.o
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/netfilter.h>
+#include <linux/skbuff.h>
+#include <linux/ip.h>
+#include <linux/udp.h>
+#include <net/tcp.h>
+#include <net/udp.h>
+
+#include <linux/netfilter_ipv4.h>
+#include <linux/netfilter_ipv4/ip_nat.h>
+#include <linux/netfilter_ipv4/ip_nat_helper.h>
+#include <linux/netfilter_ipv4/ip_conntrack_helper.h>
+#include <linux/netfilter_ipv4/ip_conntrack_amanda.h>
+
+
+MODULE_AUTHOR("Brian J. Murrell <netfilter@interlinx.bc.ca>");
+MODULE_DESCRIPTION("Amanda NAT helper");
+MODULE_LICENSE("GPL");
+
+static unsigned int help(struct sk_buff **pskb,
+ enum ip_conntrack_info ctinfo,
+ unsigned int matchoff,
+ unsigned int matchlen,
+ struct ip_conntrack_expect *exp)
+{
+ char buffer[sizeof("65535")];
+ u_int16_t port;
+ unsigned int ret;
+
+ /* Connection comes from client. */
+ exp->saved_proto.tcp.port = exp->tuple.dst.u.tcp.port;
+ exp->dir = IP_CT_DIR_ORIGINAL;
+
+ /* When you see the packet, we need to NAT it the same as the
+ * this one (ie. same IP: it will be TCP and master is UDP). */
+ exp->expectfn = ip_nat_follow_master;
+
+ /* Try to get same port: if not, try to change it. */
+ for (port = ntohs(exp->saved_proto.tcp.port); port != 0; port++) {
+ exp->tuple.dst.u.tcp.port = htons(port);
+ if (ip_conntrack_expect_related(exp) == 0)
+ break;
+ }
+
+ if (port == 0) {
+ ip_conntrack_expect_free(exp);
+ return NF_DROP;
+ }
+
+ sprintf(buffer, "%u", port);
+ ret = ip_nat_mangle_udp_packet(pskb, exp->master, ctinfo,
+ matchoff, matchlen,
+ buffer, strlen(buffer));
+ if (ret != NF_ACCEPT)
+ ip_conntrack_unexpect_related(exp);
+ return ret;
+}
+
+static void __exit fini(void)
+{
+ ip_nat_amanda_hook = NULL;
+ /* Make sure noone calls it, meanwhile. */
+ synchronize_net();
+}
+
+static int __init init(void)
+{
+ BUG_ON(ip_nat_amanda_hook);
+ ip_nat_amanda_hook = help;
+ return 0;
+}
+
+module_init(init);
+module_exit(fini);