netfilter: nf_nat: support IPv6 in FTP NAT helper
authorPatrick McHardy <kaber@trash.net>
Sun, 26 Aug 2012 17:14:20 +0000 (19:14 +0200)
committerPablo Neira Ayuso <pablo@netfilter.org>
Thu, 30 Aug 2012 01:00:20 +0000 (03:00 +0200)
Signed-off-by: Patrick McHardy <kaber@trash.net>
net/ipv4/netfilter/Kconfig
net/ipv4/netfilter/Makefile
net/ipv4/netfilter/nf_nat_ftp.c [deleted file]
net/netfilter/Kconfig
net/netfilter/Makefile
net/netfilter/nf_conntrack_ftp.c
net/netfilter/nf_nat_ftp.c [new file with mode: 0644]

index b26629681bdbf2ba9f5014d22f5980ccb73c3775..8c6c6920b57ae39b96697bbf5aa06505f157944c 100644 (file)
@@ -221,11 +221,6 @@ config NF_NAT_PROTO_GRE
        tristate
        depends on NF_NAT_IPV4 && NF_CT_PROTO_GRE
 
-config NF_NAT_FTP
-       tristate
-       depends on NF_CONNTRACK && NF_NAT_IPV4
-       default NF_NAT_IPV4 && NF_CONNTRACK_FTP
-
 config NF_NAT_IRC
        tristate
        depends on NF_CONNTRACK && NF_NAT_IPV4
index 0ea3acc510e25c8a4a9139b39d1a5ade22c6b013..4d8a4ad7816e98b57a1c6c6ad79dc2eaf83a1f6f 100644 (file)
@@ -21,7 +21,6 @@ obj-$(CONFIG_NF_DEFRAG_IPV4) += nf_defrag_ipv4.o
 
 # NAT helpers (nf_conntrack)
 obj-$(CONFIG_NF_NAT_AMANDA) += nf_nat_amanda.o
-obj-$(CONFIG_NF_NAT_FTP) += nf_nat_ftp.o
 obj-$(CONFIG_NF_NAT_H323) += nf_nat_h323.o
 obj-$(CONFIG_NF_NAT_IRC) += nf_nat_irc.o
 obj-$(CONFIG_NF_NAT_PPTP) += nf_nat_pptp.o
diff --git a/net/ipv4/netfilter/nf_nat_ftp.c b/net/ipv4/netfilter/nf_nat_ftp.c
deleted file mode 100644 (file)
index dd5e387..0000000
+++ /dev/null
@@ -1,137 +0,0 @@
-/* FTP extension for TCP NAT alteration. */
-
-/* (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/module.h>
-#include <linux/moduleparam.h>
-#include <linux/ip.h>
-#include <linux/tcp.h>
-#include <linux/netfilter_ipv4.h>
-#include <net/netfilter/nf_nat.h>
-#include <net/netfilter/nf_nat_helper.h>
-#include <net/netfilter/nf_conntrack_helper.h>
-#include <net/netfilter/nf_conntrack_expect.h>
-#include <linux/netfilter/nf_conntrack_ftp.h>
-
-MODULE_LICENSE("GPL");
-MODULE_AUTHOR("Rusty Russell <rusty@rustcorp.com.au>");
-MODULE_DESCRIPTION("ftp NAT helper");
-MODULE_ALIAS("ip_nat_ftp");
-
-/* FIXME: Time out? --RR */
-
-static int nf_nat_ftp_fmt_cmd(enum nf_ct_ftp_type type,
-                             char *buffer, size_t buflen,
-                             __be32 addr, u16 port)
-{
-       switch (type) {
-       case NF_CT_FTP_PORT:
-       case NF_CT_FTP_PASV:
-               return snprintf(buffer, buflen, "%u,%u,%u,%u,%u,%u",
-                               ((unsigned char *)&addr)[0],
-                               ((unsigned char *)&addr)[1],
-                               ((unsigned char *)&addr)[2],
-                               ((unsigned char *)&addr)[3],
-                               port >> 8,
-                               port & 0xFF);
-       case NF_CT_FTP_EPRT:
-               return snprintf(buffer, buflen, "|1|%pI4|%u|", &addr, port);
-       case NF_CT_FTP_EPSV:
-               return snprintf(buffer, buflen, "|||%u|", port);
-       }
-
-       return 0;
-}
-
-/* So, this packet has hit the connection tracking matching code.
-   Mangle it, and change the expectation to match the new version. */
-static unsigned int nf_nat_ftp(struct sk_buff *skb,
-                              enum ip_conntrack_info ctinfo,
-                              enum nf_ct_ftp_type type,
-                              unsigned int protoff,
-                              unsigned int matchoff,
-                              unsigned int matchlen,
-                              struct nf_conntrack_expect *exp)
-{
-       __be32 newip;
-       u_int16_t port;
-       int dir = CTINFO2DIR(ctinfo);
-       struct nf_conn *ct = exp->master;
-       char buffer[sizeof("|1|255.255.255.255|65535|")];
-       unsigned int buflen;
-
-       pr_debug("FTP_NAT: type %i, off %u len %u\n", type, matchoff, matchlen);
-
-       /* Connection will come from wherever this packet goes, hence !dir */
-       newip = ct->tuplehash[!dir].tuple.dst.u3.ip;
-       exp->saved_proto.tcp.port = exp->tuple.dst.u.tcp.port;
-       exp->dir = !dir;
-
-       /* When you see the packet, we need to NAT it the same as the
-        * this one. */
-       exp->expectfn = nf_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++) {
-               int ret;
-
-               exp->tuple.dst.u.tcp.port = htons(port);
-               ret = nf_ct_expect_related(exp);
-               if (ret == 0)
-                       break;
-               else if (ret != -EBUSY) {
-                       port = 0;
-                       break;
-               }
-       }
-
-       if (port == 0)
-               return NF_DROP;
-
-       buflen = nf_nat_ftp_fmt_cmd(type, buffer, sizeof(buffer), newip, port);
-       if (!buflen)
-               goto out;
-
-       pr_debug("calling nf_nat_mangle_tcp_packet\n");
-
-       if (!nf_nat_mangle_tcp_packet(skb, ct, ctinfo, protoff, matchoff,
-                                     matchlen, buffer, buflen))
-               goto out;
-
-       return NF_ACCEPT;
-
-out:
-       nf_ct_unexpect_related(exp);
-       return NF_DROP;
-}
-
-static void __exit nf_nat_ftp_fini(void)
-{
-       RCU_INIT_POINTER(nf_nat_ftp_hook, NULL);
-       synchronize_rcu();
-}
-
-static int __init nf_nat_ftp_init(void)
-{
-       BUG_ON(nf_nat_ftp_hook != NULL);
-       RCU_INIT_POINTER(nf_nat_ftp_hook, nf_nat_ftp);
-       return 0;
-}
-
-/* Prior to 2.6.11, we had a ports param.  No longer, but don't break users. */
-static int warn_set(const char *val, struct kernel_param *kp)
-{
-       printk(KERN_INFO KBUILD_MODNAME
-              ": kernel >= 2.6.10 only uses 'ports' for conntrack modules\n");
-       return 0;
-}
-module_param_call(ports, warn_set, NULL, NULL, 0);
-
-module_init(nf_nat_ftp_init);
-module_exit(nf_nat_ftp_fini);
index 91adddae20a447d70fe589bcb2b2834f94107ac7..310449450634e1a898179235ff2181f1aab3dac2 100644 (file)
@@ -380,6 +380,11 @@ config NF_NAT_PROTO_SCTP
        depends on NF_NAT && NF_CT_PROTO_SCTP
        select LIBCRC32C
 
+config NF_NAT_FTP
+       tristate
+       depends on NF_CONNTRACK && NF_NAT
+       default NF_NAT && NF_CONNTRACK_FTP
+
 endif # NF_CONNTRACK
 
 # transparent proxy support
index 09c9451bc51054b967db6b4c31558b10e96f4072..16592b1e5344d193f85cc4d5ad8fb7b23f39614e 100644 (file)
@@ -54,6 +54,9 @@ obj-$(CONFIG_NF_NAT_PROTO_DCCP) += nf_nat_proto_dccp.o
 obj-$(CONFIG_NF_NAT_PROTO_UDPLITE) += nf_nat_proto_udplite.o
 obj-$(CONFIG_NF_NAT_PROTO_SCTP) += nf_nat_proto_sctp.o
 
+# NAT helpers
+obj-$(CONFIG_NF_NAT_FTP) += nf_nat_ftp.o
+
 # transparent proxy support
 obj-$(CONFIG_NETFILTER_TPROXY) += nf_tproxy_core.o
 
index c0f4a5ba9016fa246d831a62bdb878b187db7ea2..f8cc26ad4456a2bdd0b919130cf8b9b56dca5e13 100644 (file)
@@ -488,8 +488,7 @@ static int help(struct sk_buff *skb,
        /* Now, NAT might want to mangle the packet, and register the
         * (possibly changed) expectation itself. */
        nf_nat_ftp = rcu_dereference(nf_nat_ftp_hook);
-       if (nf_nat_ftp && nf_ct_l3num(ct) == NFPROTO_IPV4 &&
-           ct->status & IPS_NAT_MASK)
+       if (nf_nat_ftp && ct->status & IPS_NAT_MASK)
                ret = nf_nat_ftp(skb, ctinfo, search[dir][i].ftptype,
                                 protoff, matchoff, matchlen, exp);
        else {
diff --git a/net/netfilter/nf_nat_ftp.c b/net/netfilter/nf_nat_ftp.c
new file mode 100644 (file)
index 0000000..e839b97
--- /dev/null
@@ -0,0 +1,143 @@
+/* FTP extension for TCP NAT alteration. */
+
+/* (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/module.h>
+#include <linux/moduleparam.h>
+#include <linux/inet.h>
+#include <linux/tcp.h>
+#include <linux/netfilter_ipv4.h>
+#include <net/netfilter/nf_nat.h>
+#include <net/netfilter/nf_nat_helper.h>
+#include <net/netfilter/nf_conntrack_helper.h>
+#include <net/netfilter/nf_conntrack_expect.h>
+#include <linux/netfilter/nf_conntrack_ftp.h>
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Rusty Russell <rusty@rustcorp.com.au>");
+MODULE_DESCRIPTION("ftp NAT helper");
+MODULE_ALIAS("ip_nat_ftp");
+
+/* FIXME: Time out? --RR */
+
+static int nf_nat_ftp_fmt_cmd(struct nf_conn *ct, enum nf_ct_ftp_type type,
+                             char *buffer, size_t buflen,
+                             union nf_inet_addr *addr, u16 port)
+{
+       switch (type) {
+       case NF_CT_FTP_PORT:
+       case NF_CT_FTP_PASV:
+               return snprintf(buffer, buflen, "%u,%u,%u,%u,%u,%u",
+                               ((unsigned char *)&addr->ip)[0],
+                               ((unsigned char *)&addr->ip)[1],
+                               ((unsigned char *)&addr->ip)[2],
+                               ((unsigned char *)&addr->ip)[3],
+                               port >> 8,
+                               port & 0xFF);
+       case NF_CT_FTP_EPRT:
+               if (nf_ct_l3num(ct) == NFPROTO_IPV4)
+                       return snprintf(buffer, buflen, "|1|%pI4|%u|",
+                                       &addr->ip, port);
+               else
+                       return snprintf(buffer, buflen, "|2|%pI6|%u|",
+                                       &addr->ip6, port);
+       case NF_CT_FTP_EPSV:
+               return snprintf(buffer, buflen, "|||%u|", port);
+       }
+
+       return 0;
+}
+
+/* So, this packet has hit the connection tracking matching code.
+   Mangle it, and change the expectation to match the new version. */
+static unsigned int nf_nat_ftp(struct sk_buff *skb,
+                              enum ip_conntrack_info ctinfo,
+                              enum nf_ct_ftp_type type,
+                              unsigned int protoff,
+                              unsigned int matchoff,
+                              unsigned int matchlen,
+                              struct nf_conntrack_expect *exp)
+{
+       union nf_inet_addr newaddr;
+       u_int16_t port;
+       int dir = CTINFO2DIR(ctinfo);
+       struct nf_conn *ct = exp->master;
+       char buffer[sizeof("|1||65535|") + INET6_ADDRSTRLEN];
+       unsigned int buflen;
+
+       pr_debug("FTP_NAT: type %i, off %u len %u\n", type, matchoff, matchlen);
+
+       /* Connection will come from wherever this packet goes, hence !dir */
+       newaddr = ct->tuplehash[!dir].tuple.dst.u3;
+       exp->saved_proto.tcp.port = exp->tuple.dst.u.tcp.port;
+       exp->dir = !dir;
+
+       /* When you see the packet, we need to NAT it the same as the
+        * this one. */
+       exp->expectfn = nf_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++) {
+               int ret;
+
+               exp->tuple.dst.u.tcp.port = htons(port);
+               ret = nf_ct_expect_related(exp);
+               if (ret == 0)
+                       break;
+               else if (ret != -EBUSY) {
+                       port = 0;
+                       break;
+               }
+       }
+
+       if (port == 0)
+               return NF_DROP;
+
+       buflen = nf_nat_ftp_fmt_cmd(ct, type, buffer, sizeof(buffer),
+                                   &newaddr, port);
+       if (!buflen)
+               goto out;
+
+       pr_debug("calling nf_nat_mangle_tcp_packet\n");
+
+       if (!nf_nat_mangle_tcp_packet(skb, ct, ctinfo, protoff, matchoff,
+                                     matchlen, buffer, buflen))
+               goto out;
+
+       return NF_ACCEPT;
+
+out:
+       nf_ct_unexpect_related(exp);
+       return NF_DROP;
+}
+
+static void __exit nf_nat_ftp_fini(void)
+{
+       RCU_INIT_POINTER(nf_nat_ftp_hook, NULL);
+       synchronize_rcu();
+}
+
+static int __init nf_nat_ftp_init(void)
+{
+       BUG_ON(nf_nat_ftp_hook != NULL);
+       RCU_INIT_POINTER(nf_nat_ftp_hook, nf_nat_ftp);
+       return 0;
+}
+
+/* Prior to 2.6.11, we had a ports param.  No longer, but don't break users. */
+static int warn_set(const char *val, struct kernel_param *kp)
+{
+       printk(KERN_INFO KBUILD_MODNAME
+              ": kernel >= 2.6.10 only uses 'ports' for conntrack modules\n");
+       return 0;
+}
+module_param_call(ports, warn_set, NULL, NULL, 0);
+
+module_init(nf_nat_ftp_init);
+module_exit(nf_nat_ftp_fini);