@@ -454,6 +454,14 @@ struct ovs_key_ct_labels {
#define OVS_CS_F_REPLY_DIR 0x08 /* Flow is in the reply direction. */
#define OVS_CS_F_INVALID 0x10 /* Could not track connection. */
#define OVS_CS_F_TRACKED 0x20 /* Conntrack has occurred. */
+#define OVS_CS_F_SRC_NAT 0x40 /* Packet's source address/port was
+ * mangled by NAT.
+ */
+#define OVS_CS_F_DST_NAT 0x80 /* Packet's destination address/port
+ * was mangled by NAT.
+ */
+
+#define OVS_CS_F_NAT_MASK (OVS_CS_F_SRC_NAT | OVS_CS_F_DST_NAT)
/**
* enum ovs_flow_attr - attributes for %OVS_FLOW_* commands.
@@ -632,6 +640,8 @@ struct ovs_action_hash {
* mask. For each bit set in the mask, the corresponding bit in the value is
* copied to the connection tracking label field in the connection.
* @OVS_CT_ATTR_HELPER: variable length string defining conntrack ALG.
+ * @OVS_CT_ATTR_NAT: Nested OVS_NAT_ATTR_* for performing L3 network address
+ * translation (NAT) on the packet.
*/
enum ovs_ct_attr {
OVS_CT_ATTR_UNSPEC,
@@ -641,12 +651,51 @@ enum ovs_ct_attr {
OVS_CT_ATTR_LABELS, /* labels to associate with this connection. */
OVS_CT_ATTR_HELPER, /* netlink helper to assist detection of
related connections. */
+ OVS_CT_ATTR_NAT, /* Nested OVS_NAT_ATTR_* */
__OVS_CT_ATTR_MAX
};
#define OVS_CT_ATTR_MAX (__OVS_CT_ATTR_MAX - 1)
/**
+ * enum ovs_nat_attr - Attributes for %OVS_CT_ATTR_NAT.
+ *
+ * @OVS_NAT_ATTR_SRC: Flag for Source NAT (mangle source address/port).
+ * @OVS_NAT_ATTR_DST: Flag for Destination NAT (mangle destination
+ * address/port). Only one of (@OVS_NAT_ATTR_SRC, @OVS_NAT_ATTR_DST) may be
+ * specified. Effective only for packets for ct_state NEW connections.
+ * Packets of committed connections are mangled by the NAT action according to
+ * the committed NAT type regardless of the flags specified. As a corollary, a
+ * NAT action without a NAT type flag will only mangle packets of committed
+ * connections. The following NAT attributes only apply for NEW
+ * (non-committed) connections, and they may be included only when the CT
+ * action has the @OVS_CT_ATTR_COMMIT flag and either @OVS_NAT_ATTR_SRC or
+ * @OVS_NAT_ATTR_DST is also included.
+ * @OVS_NAT_ATTR_IP_MIN: struct in_addr or struct in6_addr
+ * @OVS_NAT_ATTR_IP_MAX: struct in_addr or struct in6_addr
+ * @OVS_NAT_ATTR_PROTO_MIN: u16 L4 protocol specific lower boundary (port)
+ * @OVS_NAT_ATTR_PROTO_MAX: u16 L4 protocol specific upper boundary (port)
+ * @OVS_NAT_ATTR_PERSISTENT: Flag for persistent IP mapping across reboots
+ * @OVS_NAT_ATTR_PROTO_HASH: Flag for pseudo random L4 port mapping (MD5)
+ * @OVS_NAT_ATTR_PROTO_RANDOM: Flag for fully randomized L4 port mapping
+ */
+enum ovs_nat_attr {
+ OVS_NAT_ATTR_UNSPEC,
+ OVS_NAT_ATTR_SRC,
+ OVS_NAT_ATTR_DST,
+ OVS_NAT_ATTR_IP_MIN,
+ OVS_NAT_ATTR_IP_MAX,
+ OVS_NAT_ATTR_PROTO_MIN,
+ OVS_NAT_ATTR_PROTO_MAX,
+ OVS_NAT_ATTR_PERSISTENT,
+ OVS_NAT_ATTR_PROTO_HASH,
+ OVS_NAT_ATTR_PROTO_RANDOM,
+ __OVS_NAT_ATTR_MAX,
+};
+
+#define OVS_NAT_ATTR_MAX (__OVS_NAT_ATTR_MAX - 1)
+
+/**
* enum ovs_action_attr - Action types.
*
* @OVS_ACTION_ATTR_OUTPUT: Output packet to port.
@@ -6,7 +6,8 @@ config OPENVSWITCH
tristate "Open vSwitch"
depends on INET
depends on !NF_CONNTRACK || \
- (NF_CONNTRACK && (!NF_DEFRAG_IPV6 || NF_DEFRAG_IPV6))
+ (NF_CONNTRACK && ((!NF_DEFRAG_IPV6 || NF_DEFRAG_IPV6) && \
+ (!NF_NAT || NF_NAT)))
select LIBCRC32C
select MPLS
select NET_MPLS_GSO
@@ -20,14 +20,24 @@
#include <net/netfilter/nf_conntrack_zones.h>
#include <net/netfilter/ipv6/nf_defrag_ipv6.h>
+#ifdef CONFIG_NF_NAT_NEEDED
+#include <linux/netfilter/nf_nat.h>
+#include <net/netfilter/nf_nat_core.h>
+#include <net/netfilter/nf_nat_l3proto.h>
+#include <net/netfilter/nf_conntrack_seqadj.h>
+#include <linux/sctp.h>
+#include <linux/tcp.h>
+#include <linux/udp.h>
+#endif
+
#include "datapath.h"
#include "conntrack.h"
#include "flow.h"
#include "flow_netlink.h"
struct ovs_ct_len_tbl {
- size_t maxlen;
- size_t minlen;
+ int maxlen;
+ int minlen;
};
/* Metadata mark for masked write to conntrack mark */
@@ -42,15 +52,29 @@ struct md_labels {
struct ovs_key_ct_labels mask;
};
+#ifdef CONFIG_NF_NAT_NEEDED
+enum ovs_ct_nat {
+ OVS_CT_NAT = 1 << 0, /* NAT for committed connections only. */
+ OVS_CT_SRC_NAT = 1 << 1, /* Source NAT for NEW connections. */
+ OVS_CT_DST_NAT = 1 << 2, /* Destination NAT for NEW connections. */
+};
+#endif
+
/* Conntrack action context for execution. */
struct ovs_conntrack_info {
struct nf_conntrack_helper *helper;
struct nf_conntrack_zone zone;
struct nf_conn *ct;
u8 commit : 1;
+#ifdef CONFIG_NF_NAT_NEEDED
+ u8 nat : 3; /* enum ovs_ct_nat */
+#endif
u16 family;
struct md_mark mark;
struct md_labels labels;
+#ifdef CONFIG_NF_NAT_NEEDED
+ struct nf_nat_range range; /* Only present for SRC NAT and DST NAT. */
+#endif
};
static void __ovs_ct_free_action(struct ovs_conntrack_info *ct_info);
@@ -137,12 +161,15 @@ static void __ovs_ct_update_key(struct sw_flow_key *key, u8 state,
ovs_ct_get_labels(ct, &key->ct.labels);
}
-/* Update 'key' based on skb->nfct. If 'post_ct' is true, then OVS has
- * previously sent the packet to conntrack via the ct action.
+/* Update 'key' based on skb->nfct. If 'post_ct' is true, then OVS has
+ * previously sent the packet to conntrack via the ct action. If
+ * 'keep_nat_flags' is true, the existing NAT flags retained, else they are
+ * initialized from the connection status.
*/
static void ovs_ct_update_key(const struct sk_buff *skb,
const struct ovs_conntrack_info *info,
- struct sw_flow_key *key, bool post_ct)
+ struct sw_flow_key *key, bool post_ct,
+ bool keep_nat_flags)
{
const struct nf_conntrack_zone *zone = &nf_ct_zone_dflt;
enum ip_conntrack_info ctinfo;
@@ -160,6 +187,16 @@ static void ovs_ct_update_key(const struct sk_buff *skb,
*/
if (ct->master)
state |= OVS_CS_F_RELATED;
+#ifdef CONFIG_NF_NAT_NEEDED
+ if (keep_nat_flags) {
+ state |= key->ct.state & OVS_CS_F_NAT_MASK;
+ } else {
+ if (ct->status & IPS_SRC_NAT)
+ state |= OVS_CS_F_SRC_NAT;
+ if (ct->status & IPS_DST_NAT)
+ state |= OVS_CS_F_DST_NAT;
+ }
+#endif
zone = nf_ct_zone(ct);
} else if (post_ct) {
state = OVS_CS_F_TRACKED | OVS_CS_F_INVALID;
@@ -174,7 +211,7 @@ static void ovs_ct_update_key(const struct sk_buff *skb,
*/
void ovs_ct_fill_key(const struct sk_buff *skb, struct sw_flow_key *key)
{
- ovs_ct_update_key(skb, NULL, key, false);
+ ovs_ct_update_key(skb, NULL, key, false, false);
}
int ovs_ct_put_key(const struct sw_flow_key *key, struct sk_buff *skb)
@@ -263,6 +300,7 @@ static int ovs_ct_helper(struct sk_buff *skb, u16 proto)
enum ip_conntrack_info ctinfo;
unsigned int protoff;
struct nf_conn *ct;
+ int err;
ct = nf_ct_get(skb, &ctinfo);
if (!ct || ctinfo == IP_CT_RELATED_REPLY)
@@ -299,7 +337,20 @@ static int ovs_ct_helper(struct sk_buff *skb, u16 proto)
return NF_DROP;
}
- return helper->help(skb, protoff, ct, ctinfo);
+ err = helper->help(skb, protoff, ct, ctinfo);
+ if (err != NF_ACCEPT)
+ return err;
+
+#ifdef CONFIG_NF_NAT_NEEDED
+ /* Adjust seqs after helper. This is needed due to some helpers (e.g.,
+ * FTP with NAT) adusting the TCP payload size when mangling IP
+ * addresses and/or port numbers in the text-based control connection.
+ */
+ if (test_bit(IPS_SEQ_ADJUST_BIT, &ct->status) &&
+ !nf_ct_seq_adjust(skb, ct, ctinfo, protoff))
+ return NF_DROP;
+#endif
+ return NF_ACCEPT;
}
/* Returns 0 on success, -EINPROGRESS if 'skb' is stolen, or other nonzero
@@ -468,6 +519,192 @@ static bool skb_nfct_cached(struct net *net,
return true;
}
+#ifdef CONFIG_NF_NAT_NEEDED
+/* Modelled after nf_nat_ipv[46]_fn().
+ * range is only used for new, uninitialized NAT state.
+ * Returns either NF_ACCEPT or NF_DROP.
+ */
+static int ovs_ct_nat_execute(struct sk_buff *skb, struct nf_conn *ct,
+ enum ip_conntrack_info ctinfo,
+ const struct nf_nat_range *range,
+ enum nf_nat_manip_type maniptype)
+{
+ int hooknum, nh_off, err = NF_ACCEPT;
+
+ nh_off = skb_network_offset(skb);
+ skb_pull(skb, nh_off);
+
+ /* See HOOK2MANIP(). */
+ if (maniptype == NF_NAT_MANIP_SRC)
+ hooknum = NF_INET_LOCAL_IN; /* Source NAT */
+ else
+ hooknum = NF_INET_LOCAL_OUT; /* Destination NAT */
+
+ switch (ctinfo) {
+ case IP_CT_RELATED:
+ case IP_CT_RELATED_REPLY:
+ if (skb->protocol == htons(ETH_P_IP) &&
+ ip_hdr(skb)->protocol == IPPROTO_ICMP) {
+ if (!nf_nat_icmp_reply_translation(skb, ct, ctinfo,
+ hooknum))
+ err = NF_DROP;
+ goto push;
+#if IS_ENABLED(CONFIG_NF_NAT_IPV6)
+ } else if (skb->protocol == htons(ETH_P_IPV6)) {
+ __be16 frag_off;
+ u8 nexthdr = ipv6_hdr(skb)->nexthdr;
+ int hdrlen = ipv6_skip_exthdr(skb,
+ sizeof(struct ipv6hdr),
+ &nexthdr, &frag_off);
+
+ if (hdrlen >= 0 && nexthdr == IPPROTO_ICMPV6) {
+ if (!nf_nat_icmpv6_reply_translation(skb, ct,
+ ctinfo,
+ hooknum,
+ hdrlen))
+ err = NF_DROP;
+ goto push;
+ }
+#endif
+ }
+ /* Non-ICMP, fall thru to initialize if needed. */
+ case IP_CT_NEW:
+ /* Seen it before? This can happen for loopback, retrans,
+ * or local packets.
+ */
+ if (!nf_nat_initialized(ct, maniptype)) {
+ /* Initialize according to the NAT action. */
+ err = (range && range->flags & NF_NAT_RANGE_MAP_IPS)
+ /* Action is set up to establish a new
+ * mapping.
+ */
+ ? nf_nat_setup_info(ct, range, maniptype)
+ : nf_nat_alloc_null_binding(ct, hooknum);
+ if (err != NF_ACCEPT)
+ goto push;
+ }
+ break;
+
+ case IP_CT_ESTABLISHED:
+ case IP_CT_ESTABLISHED_REPLY:
+ break;
+
+ default:
+ err = NF_DROP;
+ goto push;
+ }
+
+ err = nf_nat_packet(ct, ctinfo, hooknum, skb);
+push:
+ skb_push(skb, nh_off);
+
+ return err;
+}
+
+static void ovs_nat_update_key(struct sw_flow_key *key,
+ const struct sk_buff *skb,
+ enum nf_nat_manip_type maniptype)
+{
+ if (maniptype == NF_NAT_MANIP_SRC) {
+ __be16 src;
+
+ key->ct.state |= OVS_CS_F_SRC_NAT;
+ if (key->eth.type == htons(ETH_P_IP))
+ key->ipv4.addr.src = ip_hdr(skb)->saddr;
+ else if (key->eth.type == htons(ETH_P_IPV6))
+ memcpy(&key->ipv6.addr.src, &ipv6_hdr(skb)->saddr,
+ sizeof(key->ipv6.addr.src));
+ else
+ return;
+
+ if (key->ip.proto == IPPROTO_UDP)
+ src = udp_hdr(skb)->source;
+ else if (key->ip.proto == IPPROTO_TCP)
+ src = tcp_hdr(skb)->source;
+ else if (key->ip.proto == IPPROTO_SCTP)
+ src = sctp_hdr(skb)->source;
+ else
+ return;
+
+ key->tp.src = src;
+ } else {
+ __be16 dst;
+
+ key->ct.state |= OVS_CS_F_DST_NAT;
+ if (key->eth.type == htons(ETH_P_IP))
+ key->ipv4.addr.dst = ip_hdr(skb)->daddr;
+ else if (key->eth.type == htons(ETH_P_IPV6))
+ memcpy(&key->ipv6.addr.dst, &ipv6_hdr(skb)->daddr,
+ sizeof(key->ipv6.addr.dst));
+ else
+ return;
+
+ if (key->ip.proto == IPPROTO_UDP)
+ dst = udp_hdr(skb)->dest;
+ else if (key->ip.proto == IPPROTO_TCP)
+ dst = tcp_hdr(skb)->dest;
+ else if (key->ip.proto == IPPROTO_SCTP)
+ dst = sctp_hdr(skb)->dest;
+ else
+ return;
+
+ key->tp.dst = dst;
+ }
+}
+
+/* Returns NF_DROP if the packet should be dropped, NF_ACCEPT otherwise. */
+static int ovs_ct_nat(struct net *net, struct sw_flow_key *key,
+ const struct ovs_conntrack_info *info,
+ struct sk_buff *skb, struct nf_conn *ct,
+ enum ip_conntrack_info ctinfo)
+{
+ enum nf_nat_manip_type maniptype;
+ int err;
+
+ if (nf_ct_is_untracked(ct)) {
+ /* A NAT action may only be performed on tracked packets. */
+ return NF_ACCEPT;
+ }
+
+ /* Add NAT extension if not confirmed yet. */
+ if (!nf_ct_is_confirmed(ct) && !nf_ct_nat_ext_add(ct))
+ return NF_ACCEPT; /* Can't NAT. */
+
+ /* Determine NAT type.
+ * Check if the NAT type can be deduced from the tracked connection.
+ * Make sure expected traffic is NATted only when committing.
+ */
+ if (info->nat & OVS_CT_NAT && ctinfo != IP_CT_NEW &&
+ ct->status & IPS_NAT_MASK &&
+ (!(ct->status & IPS_EXPECTED_BIT) || info->commit)) {
+ /* NAT an established or related connection like before. */
+ if (CTINFO2DIR(ctinfo) == IP_CT_DIR_REPLY)
+ /* This is the REPLY direction for a connection
+ * for which NAT was applied in the forward
+ * direction. Do the reverse NAT.
+ */
+ maniptype = ct->status & IPS_SRC_NAT
+ ? NF_NAT_MANIP_DST : NF_NAT_MANIP_SRC;
+ else
+ maniptype = ct->status & IPS_SRC_NAT
+ ? NF_NAT_MANIP_SRC : NF_NAT_MANIP_DST;
+ } else if (info->nat & OVS_CT_SRC_NAT) {
+ maniptype = NF_NAT_MANIP_SRC;
+ } else if (info->nat & OVS_CT_DST_NAT) {
+ maniptype = NF_NAT_MANIP_DST;
+ } else {
+ return NF_ACCEPT; /* Connection is not NATed. */
+ }
+ err = ovs_ct_nat_execute(skb, ct, ctinfo, &info->range, maniptype);
+
+ /* Mark NAT done if successful and update the flow key. */
+ if (err == NF_ACCEPT)
+ ovs_nat_update_key(key, skb, maniptype);
+
+ return err;
+}
+#endif
+
/* Pass 'skb' through conntrack in 'net', using zone configured in 'info', if
* not done already. Update key with new CT state after passing the packet
* through conntrack.
@@ -509,18 +746,43 @@ static int __ovs_ct_lookup(struct net *net, struct sw_flow_key *key,
if (err != NF_ACCEPT)
return -ENOENT;
- ovs_ct_update_key(skb, info, key, true);
+ /* Clear CT state NAT flags to mark that we have not yet done
+ * NAT after the nf_conntrack_in() call. We can actually clear
+ * the whole state, as it will be re-initialized below.
+ */
+ key->ct.state = 0;
+
+ /* Update the key, but keep the NAT flags. */
+ ovs_ct_update_key(skb, info, key, true, true);
}
- /* Call the helper only if we did nf_conntrack_in() above ('!cached')
- * for confirmed connections, but only when committing for unconfirmed
- * connections.
- */
ct = nf_ct_get(skb, &ctinfo);
- if (ct && (nf_ct_is_confirmed(ct) ? !cached : info->commit) &&
- ovs_ct_helper(skb, info->family) != NF_ACCEPT) {
- WARN_ONCE(1, "helper rejected packet");
- return -EINVAL;
+ if (ct) {
+#ifdef CONFIG_NF_NAT_NEEDED
+ /* Packets starting a new connection must be NATted before the
+ * helper, so that the helper knows about the NAT. We enforce
+ * this by delaying both NAT and helper calls for unconfirmed
+ * connections until the committing CT action. For later
+ * packets NAT and Helper may be called in either order.
+ *
+ * NAT will be done only if the CT action has NAT, and only
+ * once per packet (per zone), as guarded by the NAT bits in
+ * the key->ct.state.
+ */
+ if (info->nat && !(key->ct.state & OVS_CS_F_NAT_MASK) &&
+ (nf_ct_is_confirmed(ct) || info->commit) &&
+ ovs_ct_nat(net, key, info, skb, ct, ctinfo) != NF_ACCEPT) {
+ return -EINVAL;
+ }
+#endif
+ /* Call the helper whenever nf_conntrack_in() was called for
+ * confirmed connections ('!cached'), but only when committing
+ * for unconfirmed connections.
+ */
+ if ((nf_ct_is_confirmed(ct) ? !cached : info->commit) &&
+ ovs_ct_helper(skb, info->family) != NF_ACCEPT) {
+ return -EINVAL;
+ }
}
return 0;
@@ -544,15 +806,13 @@ static int ovs_ct_lookup(struct net *net, struct sw_flow_key *key,
if (exp) {
u8 state;
+ /* NOTE: New connections are NATted and Helped only when
+ * committed, so we are not calling into NAT here.
+ */
state = OVS_CS_F_TRACKED | OVS_CS_F_NEW | OVS_CS_F_RELATED;
__ovs_ct_update_key(key, state, &info->zone, exp->master);
- } else {
- int err;
-
- err = __ovs_ct_lookup(net, key, info, skb);
- if (err)
- return err;
- }
+ } else
+ return __ovs_ct_lookup(net, key, info, skb);
return 0;
}
@@ -652,6 +912,135 @@ static int ovs_ct_add_helper(struct ovs_conntrack_info *info, const char *name,
return 0;
}
+#ifdef CONFIG_NF_NAT_NEEDED
+static int parse_nat(const struct nlattr *attr,
+ struct ovs_conntrack_info *info, bool log)
+{
+ struct nlattr *a;
+ int rem;
+ bool have_ip_max = false;
+ bool have_proto_max = false;
+ bool ip_vers = (info->family == NFPROTO_IPV6);
+
+ nla_for_each_nested(a, attr, rem) {
+ static const int ovs_nat_attr_lens[OVS_NAT_ATTR_MAX + 1][2] = {
+ [OVS_NAT_ATTR_SRC] = {0, 0},
+ [OVS_NAT_ATTR_DST] = {0, 0},
+ [OVS_NAT_ATTR_IP_MIN] = {sizeof(struct in_addr),
+ sizeof(struct in6_addr)},
+ [OVS_NAT_ATTR_IP_MAX] = {sizeof(struct in_addr),
+ sizeof(struct in6_addr)},
+ [OVS_NAT_ATTR_PROTO_MIN] = {sizeof(u16), sizeof(u16)},
+ [OVS_NAT_ATTR_PROTO_MAX] = {sizeof(u16), sizeof(u16)},
+ [OVS_NAT_ATTR_PERSISTENT] = {0, 0},
+ [OVS_NAT_ATTR_PROTO_HASH] = {0, 0},
+ [OVS_NAT_ATTR_PROTO_RANDOM] = {0, 0},
+ };
+ int type = nla_type(a);
+
+ if (type > OVS_NAT_ATTR_MAX) {
+ OVS_NLERR(log,
+ "Unknown NAT attribute (type=%d, max=%d).\n",
+ type, OVS_NAT_ATTR_MAX);
+ return -EINVAL;
+ }
+
+ if (nla_len(a) != ovs_nat_attr_lens[type][ip_vers]) {
+ OVS_NLERR(log,
+ "NAT attribute type %d has unexpected length (%d != %d).\n",
+ type, nla_len(a),
+ ovs_nat_attr_lens[type][ip_vers]);
+ return -EINVAL;
+ }
+
+ switch (type) {
+ case OVS_NAT_ATTR_SRC:
+ case OVS_NAT_ATTR_DST:
+ if (info->nat) {
+ OVS_NLERR(log,
+ "Only one type of NAT may be specified.\n"
+ );
+ return -ERANGE;
+ }
+ info->nat |= OVS_CT_NAT;
+ info->nat |= ((type == OVS_NAT_ATTR_SRC)
+ ? OVS_CT_SRC_NAT : OVS_CT_DST_NAT);
+ break;
+
+ case OVS_NAT_ATTR_IP_MIN:
+ nla_memcpy(&info->range.min_addr, a, nla_len(a));
+ info->range.flags |= NF_NAT_RANGE_MAP_IPS;
+ break;
+
+ case OVS_NAT_ATTR_IP_MAX:
+ have_ip_max = true;
+ nla_memcpy(&info->range.max_addr, a,
+ sizeof(info->range.max_addr));
+ info->range.flags |= NF_NAT_RANGE_MAP_IPS;
+ break;
+
+ case OVS_NAT_ATTR_PROTO_MIN:
+ info->range.min_proto.all = htons(nla_get_u16(a));
+ info->range.flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
+ break;
+
+ case OVS_NAT_ATTR_PROTO_MAX:
+ have_proto_max = true;
+ info->range.max_proto.all = htons(nla_get_u16(a));
+ info->range.flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
+ break;
+
+ case OVS_NAT_ATTR_PERSISTENT:
+ info->range.flags |= NF_NAT_RANGE_PERSISTENT;
+ break;
+
+ case OVS_NAT_ATTR_PROTO_HASH:
+ info->range.flags |= NF_NAT_RANGE_PROTO_RANDOM;
+ break;
+
+ case OVS_NAT_ATTR_PROTO_RANDOM:
+ info->range.flags |= NF_NAT_RANGE_PROTO_RANDOM_FULLY;
+ break;
+
+ default:
+ OVS_NLERR(log, "Unknown nat attribute (%d).\n", type);
+ return -EINVAL;
+ }
+ }
+
+ if (rem > 0) {
+ OVS_NLERR(log, "NAT attribute has %d unknown bytes.\n", rem);
+ return -EINVAL;
+ }
+ if (!info->nat) {
+ /* Do not allow flags if no type is given. */
+ if (info->range.flags) {
+ OVS_NLERR(log,
+ "NAT flags may be given only when NAT range (SRC or DST) is also specified.\n"
+ );
+ return -EINVAL;
+ }
+ info->nat = OVS_CT_NAT; /* NAT existing connections. */
+ } else if (!info->commit) {
+ OVS_NLERR(log,
+ "NAT attributes may be specified only when CT COMMIT flag is also specified.\n"
+ );
+ return -EINVAL;
+ }
+ /* Allow missing IP_MAX. */
+ if (info->range.flags & NF_NAT_RANGE_MAP_IPS && !have_ip_max) {
+ memcpy(&info->range.max_addr, &info->range.min_addr,
+ sizeof(info->range.max_addr));
+ }
+ /* Allow missing PROTO_MAX. */
+ if (info->range.flags & NF_NAT_RANGE_PROTO_SPECIFIED &&
+ !have_proto_max) {
+ info->range.max_proto.all = info->range.min_proto.all;
+ }
+ return 0;
+}
+#endif
+
static const struct ovs_ct_len_tbl ovs_ct_attr_lens[OVS_CT_ATTR_MAX + 1] = {
[OVS_CT_ATTR_COMMIT] = { .minlen = 0, .maxlen = 0 },
[OVS_CT_ATTR_ZONE] = { .minlen = sizeof(u16),
@@ -661,7 +1050,11 @@ static const struct ovs_ct_len_tbl ovs_ct_attr_lens[OVS_CT_ATTR_MAX + 1] = {
[OVS_CT_ATTR_LABELS] = { .minlen = sizeof(struct md_labels),
.maxlen = sizeof(struct md_labels) },
[OVS_CT_ATTR_HELPER] = { .minlen = 1,
- .maxlen = NF_CT_HELPER_NAME_LEN }
+ .maxlen = NF_CT_HELPER_NAME_LEN },
+#ifdef CONFIG_NF_NAT_NEEDED
+ /* NAT length is checked when parsing the nested attributes. */
+ [OVS_CT_ATTR_NAT] = { .minlen = 0, .maxlen = INT_MAX },
+#endif
};
static int parse_ct(const struct nlattr *attr, struct ovs_conntrack_info *info,
@@ -728,6 +1121,15 @@ static int parse_ct(const struct nlattr *attr, struct ovs_conntrack_info *info,
return -EINVAL;
}
break;
+#ifdef CONFIG_NF_NAT_NEEDED
+ case OVS_CT_ATTR_NAT: {
+ int err = parse_nat(a, info, log);
+
+ if (err)
+ return err;
+ break;
+ }
+#endif
default:
OVS_NLERR(log, "Unknown conntrack attr (%d)",
type);
@@ -815,6 +1217,74 @@ err_free_ct:
return err;
}
+#ifdef CONFIG_NF_NAT_NEEDED
+static bool ovs_ct_nat_to_attr(const struct ovs_conntrack_info *info,
+ struct sk_buff *skb)
+{
+ struct nlattr *start;
+
+ start = nla_nest_start(skb, OVS_CT_ATTR_NAT);
+ if (!start)
+ return false;
+
+ if (info->nat & OVS_CT_SRC_NAT) {
+ if (nla_put_flag(skb, OVS_NAT_ATTR_SRC))
+ return false;
+ } else if (info->nat & OVS_CT_DST_NAT) {
+ if (nla_put_flag(skb, OVS_NAT_ATTR_DST))
+ return false;
+ } else {
+ goto out;
+ }
+
+ if (info->range.flags & NF_NAT_RANGE_MAP_IPS) {
+ if (info->family == NFPROTO_IPV4) {
+ if (nla_put_in_addr(skb, OVS_NAT_ATTR_IP_MIN,
+ info->range.min_addr.ip) ||
+ (info->range.max_addr.ip
+ != info->range.min_addr.ip &&
+ (nla_put_in_addr(skb, OVS_NAT_ATTR_IP_MAX,
+ info->range.max_addr.ip))))
+ return false;
+#if IS_ENABLED(CONFIG_NF_NAT_IPV6)
+ } else if (info->family == NFPROTO_IPV6) {
+ if (nla_put_in6_addr(skb, OVS_NAT_ATTR_IP_MIN,
+ &info->range.min_addr.in6) ||
+ (memcmp(&info->range.max_addr.in6,
+ &info->range.min_addr.in6,
+ sizeof(info->range.max_addr.in6)) &&
+ (nla_put_in6_addr(skb, OVS_NAT_ATTR_IP_MAX,
+ &info->range.max_addr.in6))))
+ return false;
+#endif
+ } else {
+ return false;
+ }
+ }
+ if (info->range.flags & NF_NAT_RANGE_PROTO_SPECIFIED &&
+ (nla_put_u16(skb, OVS_NAT_ATTR_PROTO_MIN,
+ ntohs(info->range.min_proto.all)) ||
+ (info->range.max_proto.all != info->range.min_proto.all &&
+ nla_put_u16(skb, OVS_NAT_ATTR_PROTO_MAX,
+ ntohs(info->range.max_proto.all)))))
+ return false;
+
+ if (info->range.flags & NF_NAT_RANGE_PERSISTENT &&
+ nla_put_flag(skb, OVS_NAT_ATTR_PERSISTENT))
+ return false;
+ if (info->range.flags & NF_NAT_RANGE_PROTO_RANDOM &&
+ nla_put_flag(skb, OVS_NAT_ATTR_PROTO_HASH))
+ return false;
+ if (info->range.flags & NF_NAT_RANGE_PROTO_RANDOM_FULLY &&
+ nla_put_flag(skb, OVS_NAT_ATTR_PROTO_RANDOM))
+ return false;
+out:
+ nla_nest_end(skb, start);
+
+ return true;
+}
+#endif
+
int ovs_ct_action_to_attr(const struct ovs_conntrack_info *ct_info,
struct sk_buff *skb)
{
@@ -843,7 +1313,10 @@ int ovs_ct_action_to_attr(const struct ovs_conntrack_info *ct_info,
ct_info->helper->name))
return -EMSGSIZE;
}
-
+#ifdef CONFIG_NF_NAT_NEEDED
+ if (ct_info->nat && !ovs_ct_nat_to_attr(ct_info, skb))
+ return -EMSGSIZE;
+#endif
nla_nest_end(skb, start);
return 0;
@@ -37,7 +37,8 @@ void ovs_ct_free_action(const struct nlattr *a);
#define CT_SUPPORTED_MASK (OVS_CS_F_NEW | OVS_CS_F_ESTABLISHED | \
OVS_CS_F_RELATED | OVS_CS_F_REPLY_DIR | \
- OVS_CS_F_INVALID | OVS_CS_F_TRACKED)
+ OVS_CS_F_INVALID | OVS_CS_F_TRACKED | \
+ OVS_CS_F_SRC_NAT | OVS_CS_F_DST_NAT)
#else
#include <linux/errno.h>
Extend OVS conntrack interface to cover NAT. New nested OVS_CT_ATTR_NAT attribute may be used to include NAT with a CT action. A bare OVS_CT_ATTR_NAT only mangles existing and expected connections. If OVS_NAT_ATTR_SRC or OVS_NAT_ATTR_DST is included within the nested attributes, new (non-committed/non-confirmed) connections are mangled according to the rest of the nested attributes. The corresponding OVS userspace patch series includes test cases (in tests/system-traffic.at) that also serve as example uses. This work extends on a branch by Thomas Graf at https://github.com/tgraf/ovs/tree/nat. Signed-off-by: Jarno Rajahalme <jarno@ovn.org> --- v9: Fixed module dependencies. include/uapi/linux/openvswitch.h | 49 ++++ net/openvswitch/Kconfig | 3 +- net/openvswitch/conntrack.c | 523 +++++++++++++++++++++++++++++++++++++-- net/openvswitch/conntrack.h | 3 +- 4 files changed, 551 insertions(+), 27 deletions(-)