| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-Id: <1321854369-3432-17-git-send-email-kaber@trash.net>
Date: Mon, 21 Nov 2011 06:46:08 +0100
From: kaber@...sh.net
To: netfilter-devel@...r.kernel.org
Cc: netdev@...r.kernel.org, kaber@...sh.net, ulrich.weber@...hos.com
Subject: [PATCH 16/17] netfilter: nf_nat: support IPv6 in FTP NAT helper
From: Patrick McHardy <kaber@...sh.net>
Signed-off-by: Patrick McHardy <kaber@...sh.net>
---
net/ipv4/netfilter/Kconfig | 5 --
net/ipv4/netfilter/Makefile | 1 -
net/ipv4/netfilter/nf_nat_ftp.c | 137 ------------------------------------
net/netfilter/Kconfig | 5 ++
net/netfilter/Makefile | 3 +
net/netfilter/nf_conntrack_ftp.c | 3 +-
net/netfilter/nf_nat_ftp.c | 142 ++++++++++++++++++++++++++++++++++++++
7 files changed, 151 insertions(+), 145 deletions(-)
delete mode 100644 net/ipv4/netfilter/nf_nat_ftp.c
create mode 100644 net/netfilter/nf_nat_ftp.c
diff --git a/net/ipv4/netfilter/Kconfig b/net/ipv4/netfilter/Kconfig
index 56a1742..1b043a5 100644
--- a/net/ipv4/netfilter/Kconfig
+++ b/net/ipv4/netfilter/Kconfig
@@ -219,11 +219,6 @@ 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
diff --git a/net/ipv4/netfilter/Makefile b/net/ipv4/netfilter/Makefile
index a655e00..0fa8715 100644
--- a/net/ipv4/netfilter/Makefile
+++ b/net/ipv4/netfilter/Makefile
@@ -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
index f0d85a1..0000000
--- a/net/ipv4/netfilter/nf_nat_ftp.c
+++ /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@...filter.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@...tcorp.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_assign_pointer(nf_nat_ftp_hook, NULL);
- synchronize_rcu();
-}
-
-static int __init nf_nat_ftp_init(void)
-{
- BUG_ON(nf_nat_ftp_hook != NULL);
- rcu_assign_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);
diff --git a/net/netfilter/Kconfig b/net/netfilter/Kconfig
index 9e29e5c..5ce87f7 100644
--- a/net/netfilter/Kconfig
+++ b/net/netfilter/Kconfig
@@ -321,6 +321,11 @@ 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
diff --git a/net/netfilter/Makefile b/net/netfilter/Makefile
index af649c1..a747580 100644
--- a/net/netfilter/Makefile
+++ b/net/netfilter/Makefile
@@ -48,6 +48,9 @@ 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
diff --git a/net/netfilter/nf_conntrack_ftp.c b/net/netfilter/nf_conntrack_ftp.c
index c6634ad..80614dd 100644
--- a/net/netfilter/nf_conntrack_ftp.c
+++ b/net/netfilter/nf_conntrack_ftp.c
@@ -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
index 0000000..26c79dd
--- /dev/null
+++ b/net/netfilter/nf_nat_ftp.c
@@ -0,0 +1,142 @@
+/* FTP extension for TCP NAT alteration. */
+
+/* (C) 1999-2001 Paul `Rusty' Russell
+ * (C) 2002-2006 Netfilter Core Team <coreteam@...filter.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/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@...tcorp.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_assign_pointer(nf_nat_ftp_hook, NULL);
+ synchronize_rcu();
+}
+
+static int __init nf_nat_ftp_init(void)
+{
+ BUG_ON(nf_nat_ftp_hook != NULL);
+ rcu_assign_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);
--
1.7.1
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Powered by blists - more mailing lists