[PATCH 16/19] netfilter: nf_nat: support IPv6 in FTP NAT helper

kaber
2012-08-09T20:09:00Z

From: Patrick McHardy <kaber@trash.net>

Signed-off-by: Patrick McHardy <kaber@trash.net>
---
net/ipv4/netfilter/Kconfig | 5 -----
net/ipv4/netfilter/Makefile | 1 -
net/netfilter/Kconfig | 5 +++++
net/netfilter/Makefile | 3 +++
net/netfilter/nf_conntrack_ftp.c | 3 +--
net/{ipv4 => }/netfilter/nf_nat_ftp.c | 30 ++++++++++++++++++------------
6 files changed, 27 insertions(+), 20 deletions(-)
rename net/{ipv4 => }/netfilter/nf_nat_ftp.c (82%)

diff --git a/net/ipv4/netfilter/Kconfig b/net/ipv4/netfilter/Kconfig
index 33372a1..80272e7 100644
--- a/net/ipv4/netfilter/Kconfig
+++ b/net/ipv4/netfilter/Kconfig
@@ -220,11 +220,6 @@ 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 0ea3acc..4d8a4ad 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/netfilter/Kconfig b/net/netfilter/Kconfig
index 91addda..3104494 100644
--- a/net/netfilter/Kconfig
+++ b/net/netfilter/Kconfig
@@ -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
diff --git a/net/netfilter/Makefile b/net/netfilter/Makefile
index 09c9451..16592b1 100644
--- a/net/netfilter/Makefile
+++ b/net/netfilter/Makefile
@@ -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

diff --git a/net/netfilter/nf_conntrack_ftp.c b/net/netfilter/nf_conntrack_ftp.c
index c0f4a5b..f8cc26a 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/ipv4/netfilter/nf_nat_ftp.c b/net/netfilter/nf_nat_ftp.c
similarity index 82%
rename from net/ipv4/netfilter/nf_nat_ftp.c
rename to net/netfilter/nf_nat_ftp.c
index dd5e387..e839b97 100644
--- a/net/ipv4/netfilter/nf_nat_ftp.c
+++ b/net/netfilter/nf_nat_ftp.c
@@ -10,7 +10,7 @@

#include <linux/module.h>
#include <linux/moduleparam.h>
-#include <linux/ip.h>
+#include <linux/inet.h>
#include <linux/tcp.h>
#include <linux/netfilter_ipv4.h>
#include <net/netfilter/nf_nat.h>
@@ -26,22 +26,27 @@ MODULE_ALIAS("ip_nat_ftp");

/* FIXME: Time out? --RR */

-static int nf_nat_ftp_fmt_cmd(enum nf_ct_ftp_type type,
+static int nf_nat_ftp_fmt_cmd(struct nf_conn *ct, enum nf_ct_ftp_type type,
char *buffer, size_t buflen,
- __be32 addr, u16 port)
+ 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)[0],
- ((unsigned char *)&addr)[1],
- ((unsigned char *)&addr)[2],
- ((unsigned char *)&addr)[3],
+ ((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:
- return snprintf(buffer, buflen, "|1|%pI4|%u|", &addr, port);
+ 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);
}
@@ -59,17 +64,17 @@ static unsigned int nf_nat_ftp(struct sk_buff *skb,
unsigned int matchlen,
struct nf_conntrack_expect *exp)
{
- __be32 newip;
+ union nf_inet_addr newaddr;
u_int16_t port;
int dir = CTINFO2DIR(ctinfo);
struct nf_conn *ct = exp->master;
- char buffer[sizeof("|1|255.255.255.255|65535|")];
+ 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 */
- newip = ct->tuplehash[!dir].tuple.dst.u3.ip;
+ newaddr = ct->tuplehash[!dir].tuple.dst.u3;
exp->saved_proto.tcp.port = exp->tuple.dst.u.tcp.port;
exp->dir = !dir;

@@ -94,7 +99,8 @@ static unsigned int nf_nat_ftp(struct sk_buff *skb,
if (port == 0)
return NF_DROP;

- buflen = nf_nat_ftp_fmt_cmd(type, buffer, sizeof(buffer), newip, port);
+ buflen = nf_nat_ftp_fmt_cmd(ct, type, buffer, sizeof(buffer),
+ &newaddr, port);
if (!buflen)
goto out;

--
1.7.1