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authorFilip Varga <fivarga@cisco.com>2020-07-21 10:27:39 +0200
committerOle Trøan <otroan@employees.org>2020-08-13 10:06:33 +0000
commit603e75465899385a95350f3c96499050f7f960a5 (patch)
treef7a7130769ea795c1c3460db3aea99a49a309b13 /src/plugins/nat/det44/det44.c
parentde118da58e80aec43f4b816a1ea957634a8bc07c (diff)
nat: move deterministic nat to det44 sub feature
Type: refactor Change-Id: I0bb203102a0e13dd7448e2125925ab356bbd7937 Signed-off-by: Filip Varga <fivarga@cisco.com>
Diffstat (limited to 'src/plugins/nat/det44/det44.c')
-rw-r--r--src/plugins/nat/det44/det44.c608
1 files changed, 608 insertions, 0 deletions
diff --git a/src/plugins/nat/det44/det44.c b/src/plugins/nat/det44/det44.c
new file mode 100644
index 00000000000..886092cea50
--- /dev/null
+++ b/src/plugins/nat/det44/det44.c
@@ -0,0 +1,608 @@
+/*
+ * det44.c - deterministic NAT
+ *
+ * Copyright (c) 2020 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+/**
+ * @file
+ * @brief deterministic NAT (CGN)
+ */
+
+#include <vnet/vnet.h>
+#include <vnet/ip/ip.h>
+#include <vnet/ip/ip4.h>
+#include <vpp/app/version.h>
+#include <vnet/plugin/plugin.h>
+
+#include <nat/det44/det44.h>
+
+det44_main_t det44_main;
+
+/* *INDENT-OFF* */
+VNET_FEATURE_INIT (ip4_det44_in2out, static) = {
+ .arc_name = "ip4-unicast",
+ .node_name = "det44-in2out",
+ .runs_after = VNET_FEATURES ("acl-plugin-in-ip4-fa",
+ "ip4-sv-reassembly-feature"),
+};
+VNET_FEATURE_INIT (ip4_det44_out2in, static) = {
+ .arc_name = "ip4-unicast",
+ .node_name = "det44-out2in",
+ .runs_after = VNET_FEATURES ("acl-plugin-in-ip4-fa",
+ "ip4-sv-reassembly-feature",
+ "ip4-dhcp-client-detect"),
+};
+VLIB_PLUGIN_REGISTER () = {
+ .version = VPP_BUILD_VER,
+ .description = "Deterministic NAT (CGN)",
+};
+/* *INDENT-ON* */
+
+void
+det44_add_del_addr_to_fib (ip4_address_t * addr, u8 p_len, u32 sw_if_index,
+ int is_add)
+{
+ det44_main_t *dm = &det44_main;
+ fib_prefix_t prefix = {
+ .fp_len = p_len,
+ .fp_proto = FIB_PROTOCOL_IP4,
+ .fp_addr = {
+ .ip4.as_u32 = addr->as_u32,
+ },
+ };
+ u32 fib_index = ip4_fib_table_get_index_for_sw_if_index (sw_if_index);
+
+ if (is_add)
+ {
+ fib_table_entry_update_one_path (fib_index,
+ &prefix,
+ dm->fib_src_low,
+ (FIB_ENTRY_FLAG_CONNECTED |
+ FIB_ENTRY_FLAG_LOCAL |
+ FIB_ENTRY_FLAG_EXCLUSIVE),
+ DPO_PROTO_IP4,
+ NULL,
+ sw_if_index,
+ ~0, 1, NULL, FIB_ROUTE_PATH_FLAG_NONE);
+ }
+ else
+ {
+ fib_table_entry_delete (fib_index, &prefix, dm->fib_src_low);
+ }
+}
+
+/**
+ * @brief Add/delete deterministic NAT mapping.
+ *
+ * Create bijective mapping of inside address to outside address and port range
+ * pairs, with the purpose of enabling deterministic NAT to reduce logging in
+ * CGN deployments.
+ *
+ * @param in_addr Inside network address.
+ * @param in_plen Inside network prefix length.
+ * @param out_addr Outside network address.
+ * @param out_plen Outside network prefix length.
+ * @param is_add If 0 delete, otherwise add.
+ */
+int
+snat_det_add_map (ip4_address_t * in_addr, u8 in_plen,
+ ip4_address_t * out_addr, u8 out_plen, int is_add)
+{
+ static snat_det_session_t empty_snat_det_session = { 0 };
+ det44_main_t *dm = &det44_main;
+ ip4_address_t in_cmp, out_cmp;
+ det44_interface_t *i;
+ snat_det_map_t *mp;
+ u8 found = 0;
+
+ in_cmp.as_u32 = in_addr->as_u32 & ip4_main.fib_masks[in_plen];
+ out_cmp.as_u32 = out_addr->as_u32 & ip4_main.fib_masks[out_plen];
+ vec_foreach (mp, dm->det_maps)
+ {
+ /* Checking for overlapping addresses to be added here */
+ if (mp->in_addr.as_u32 == in_cmp.as_u32 &&
+ mp->in_plen == in_plen &&
+ mp->out_addr.as_u32 == out_cmp.as_u32 && mp->out_plen == out_plen)
+ {
+ found = 1;
+ break;
+ }
+ }
+
+ /* If found, don't add again */
+ if (found && is_add)
+ return VNET_API_ERROR_VALUE_EXIST;
+
+ /* If not found, don't delete */
+ if (!found && !is_add)
+ return VNET_API_ERROR_NO_SUCH_ENTRY;
+
+ if (is_add)
+ {
+ pool_get (dm->det_maps, mp);
+ clib_memset (mp, 0, sizeof (*mp));
+ mp->in_addr.as_u32 = in_cmp.as_u32;
+ mp->in_plen = in_plen;
+ mp->out_addr.as_u32 = out_cmp.as_u32;
+ mp->out_plen = out_plen;
+ mp->sharing_ratio = (1 << (32 - in_plen)) / (1 << (32 - out_plen));
+ mp->ports_per_host = (65535 - 1023) / mp->sharing_ratio;
+
+ vec_validate_init_empty (mp->sessions,
+ DET44_SES_PER_USER * (1 << (32 - in_plen)) -
+ 1, empty_snat_det_session);
+ }
+ else
+ {
+ vec_free (mp->sessions);
+ vec_del1 (dm->det_maps, mp - dm->det_maps);
+ }
+
+ /* Add/del external address range to FIB */
+ /* *INDENT-OFF* */
+ pool_foreach (i, dm->interfaces, ({
+ if (det44_interface_is_inside(i))
+ continue;
+ det44_add_del_addr_to_fib(out_addr, out_plen, i->sw_if_index, is_add);
+ goto out;
+ }));
+ /* *INDENT-ON* */
+out:
+ return 0;
+}
+
+int
+det44_set_timeouts (nat_timeouts_t * timeouts)
+{
+ det44_main_t *dm = &det44_main;
+ if (timeouts->udp)
+ dm->timeouts.udp = timeouts->udp;
+ if (timeouts->tcp.established)
+ dm->timeouts.tcp.established = timeouts->tcp.established;
+ if (timeouts->tcp.transitory)
+ dm->timeouts.tcp.transitory = timeouts->tcp.transitory;
+ if (timeouts->icmp)
+ dm->timeouts.icmp = timeouts->icmp;
+ return 0;
+}
+
+nat_timeouts_t
+det44_get_timeouts ()
+{
+ det44_main_t *dm = &det44_main;
+ return dm->timeouts;
+}
+
+void
+det44_reset_timeouts ()
+{
+ det44_main_t *dm = &det44_main;
+ dm->timeouts.udp = 300;
+ dm->timeouts.tcp.established = 7440;
+ dm->timeouts.tcp.transitory = 240;
+ dm->timeouts.icmp = 60;
+}
+
+int
+det44_interface_add_del (u32 sw_if_index, u8 is_inside, int is_del)
+{
+ det44_main_t *dm = &det44_main;
+ det44_interface_t *tmp, *i = 0;
+ const char *feature_name;
+ int rv;
+
+ // TODO: if plugin is not enabled do not register nodes on interfaces
+ // rather make a structure and when enable call is used
+ // then register nodes
+
+ /* *INDENT-OFF* */
+ pool_foreach (tmp, dm->interfaces, ({
+ if (tmp->sw_if_index == sw_if_index)
+ {
+ i = tmp;
+ goto out;
+ }
+ }));
+ /* *INDENT-ON* */
+out:
+
+ feature_name = is_inside ? "det44-in2out" : "det44-out2in";
+
+ if (is_del)
+ {
+ if (!i)
+ {
+ det44_log_err ("det44 is not enabled on this interface");
+ return VNET_API_ERROR_INVALID_VALUE;
+ }
+
+ rv = ip4_sv_reass_enable_disable_with_refcnt (sw_if_index, 0);
+ if (rv)
+ return rv;
+
+ rv = vnet_feature_enable_disable ("ip4-unicast", feature_name,
+ sw_if_index, 1, 0, 0);
+ if (rv)
+ return rv;
+
+ pool_put (dm->interfaces, i);
+ }
+ else
+ {
+ if (i)
+ {
+ det44_log_err ("det44 is already enabled on this interface");
+ return VNET_API_ERROR_INVALID_VALUE;
+ }
+
+ rv = ip4_sv_reass_enable_disable_with_refcnt (sw_if_index, 1);
+ if (rv)
+ return rv;
+
+ rv = vnet_feature_enable_disable ("ip4-unicast", feature_name,
+ sw_if_index, 1, 0, 0);
+ if (rv)
+ return rv;
+
+ pool_get (dm->interfaces, i);
+ clib_memset (i, 0, sizeof (*i));
+
+ i->sw_if_index = sw_if_index;
+
+ if (is_inside)
+ i->flags |= DET44_INTERFACE_FLAG_IS_INSIDE;
+ else
+ i->flags |= DET44_INTERFACE_FLAG_IS_OUTSIDE;
+ }
+
+ if (!is_inside)
+ {
+ u32 fib_index = fib_table_get_index_for_sw_if_index (FIB_PROTOCOL_IP4,
+ sw_if_index);
+ // add/del outside interface fib to registry
+ u8 found = 0;
+ det44_fib_t *outside_fib;
+ /* *INDENT-OFF* */
+ vec_foreach (outside_fib, dm->outside_fibs)
+ {
+ if (outside_fib->fib_index == fib_index)
+ {
+ if (!is_del)
+ {
+ outside_fib->refcount++;
+ }
+ else
+ {
+ outside_fib->refcount--;
+ if (!outside_fib->refcount)
+ {
+ vec_del1 (dm->outside_fibs,
+ outside_fib - dm->outside_fibs);
+ }
+ }
+ found = 1;
+ break;
+ }
+ }
+ /* *INDENT-ON* */
+ if (!is_del && !found)
+ {
+ vec_add2 (dm->outside_fibs, outside_fib, 1);
+ outside_fib->fib_index = fib_index;
+ outside_fib->refcount = 1;
+ }
+ // add/del outside address to FIB
+ snat_det_map_t *mp;
+ /* *INDENT-OFF* */
+ pool_foreach (mp, dm->det_maps, ({
+ det44_add_del_addr_to_fib(&mp->out_addr,
+ mp->out_plen, sw_if_index, !is_del);
+ }));
+ /* *INDENT-ON* */
+ }
+ return 0;
+}
+
+/**
+ * @brief The 'det44-expire-walk' process's main loop.
+ *
+ * Check expire time for active sessions.
+ */
+static uword
+det44_expire_walk_fn (vlib_main_t * vm, vlib_node_runtime_t * rt,
+ vlib_frame_t * f)
+{
+ det44_main_t *dm = &det44_main;
+ snat_det_session_t *ses;
+ snat_det_map_t *mp;
+
+ vlib_process_wait_for_event_or_clock (vm, 10.0);
+ vlib_process_get_events (vm, NULL);
+ u32 now = (u32) vlib_time_now (vm);
+ /* *INDENT-OFF* */
+ pool_foreach (mp, dm->det_maps, ({
+ vec_foreach(ses, mp->sessions)
+ {
+ /* Delete if session expired */
+ if (ses->in_port && (ses->expire < now))
+ snat_det_ses_close (mp, ses);
+ }
+ }));
+ /* *INDENT-ON* */
+ return 0;
+}
+
+void
+det44_create_expire_walk_process ()
+{
+ det44_main_t *dm = &det44_main;
+
+ if (dm->expire_walk_node_index)
+ return;
+
+ dm->expire_walk_node_index = vlib_process_create (vlib_get_main (),
+ "det44-expire-walk",
+ det44_expire_walk_fn,
+ 16 /* stack_bytes */ );
+}
+
+int
+det44_plugin_enable (det44_config_t c)
+{
+ det44_main_t *dm = &det44_main;
+
+ if (plugin_enabled () == 1)
+ {
+ det44_log_err ("plugin already enabled!");
+ return 1;
+ }
+
+ det44_log_err ("inside %u, outside %u", c.inside_vrf_id, c.outside_vrf_id);
+
+ dm->outside_fib_index = fib_table_find_or_create_and_lock (FIB_PROTOCOL_IP4,
+ c.outside_vrf_id,
+ dm->fib_src_hi);
+ dm->inside_fib_index = fib_table_find_or_create_and_lock (FIB_PROTOCOL_IP4,
+ c.inside_vrf_id,
+ dm->fib_src_hi);
+
+ det44_create_expire_walk_process ();
+ dm->mss_clamping = 0;
+ dm->config = c;
+ dm->enabled = 1;
+ return 0;
+}
+
+int
+det44_plugin_disable ()
+{
+ det44_main_t *dm = &det44_main;
+ det44_interface_t *i, *interfaces;
+ snat_det_map_t *mp;
+ int rv = 0;
+
+ if (plugin_enabled () == 0)
+ {
+ det44_log_err ("plugin already disabled!");
+ return 1;
+ }
+
+ // DET44 cleanup (order dependent)
+ // 1) remove interfaces (det44_interface_add_del) removes map ranges from fib
+ // 2) free sessions
+ // 3) free maps
+
+ interfaces = vec_dup (dm->interfaces);
+ vec_foreach (i, interfaces)
+ {
+ vnet_main_t *vnm = vnet_get_main ();
+
+ if (i->flags & DET44_INTERFACE_FLAG_IS_INSIDE)
+ {
+ rv = det44_interface_add_del (i->sw_if_index, i->flags, 1);
+ if (rv)
+ {
+ det44_log_err ("inside interface %U del failed",
+ unformat_vnet_sw_interface, vnm, i->sw_if_index);
+ }
+ }
+
+ if (i->flags & DET44_INTERFACE_FLAG_IS_OUTSIDE)
+ {
+ rv = det44_interface_add_del (i->sw_if_index, i->flags, 1);
+ if (rv)
+ {
+ det44_log_err ("outside interface %U del failed",
+ unformat_vnet_sw_interface, vnm, i->sw_if_index);
+ }
+
+ }
+ }
+ vec_free (interfaces);
+
+ /* *INDENT-OFF* */
+ pool_foreach (mp, dm->det_maps,
+ ({
+ vec_free (mp->sessions);
+ }));
+ /* *INDENT-ON* */
+
+ det44_reset_timeouts ();
+ dm->enabled = 0;
+
+ pool_free (dm->interfaces);
+ pool_free (dm->det_maps);
+
+ return rv;
+}
+
+static void
+det44_update_outside_fib (ip4_main_t * im,
+ uword opaque,
+ u32 sw_if_index, u32 new_fib_index,
+ u32 old_fib_index)
+{
+ det44_main_t *dm = &det44_main;
+
+ det44_fib_t *outside_fib;
+ det44_interface_t *i;
+
+ u8 is_add = 1;
+ u8 match = 0;
+
+ if (plugin_enabled () == 0)
+ return;
+
+ if (new_fib_index == old_fib_index)
+ return;
+
+ if (!vec_len (dm->outside_fibs))
+ return;
+
+ /* *INDENT-OFF* */
+ pool_foreach (i, dm->interfaces,
+ ({
+ if (i->sw_if_index == sw_if_index)
+ {
+ if (!(det44_interface_is_outside (i)))
+ return;
+ match = 1;
+ }
+ }));
+ /* *INDENT-ON* */
+
+ if (!match)
+ return;
+
+ vec_foreach (outside_fib, dm->outside_fibs)
+ {
+ if (outside_fib->fib_index == old_fib_index)
+ {
+ outside_fib->refcount--;
+ if (!outside_fib->refcount)
+ vec_del1 (dm->outside_fibs, outside_fib - dm->outside_fibs);
+ break;
+ }
+ }
+
+ vec_foreach (outside_fib, dm->outside_fibs)
+ {
+ if (outside_fib->fib_index == new_fib_index)
+ {
+ outside_fib->refcount++;
+ is_add = 0;
+ break;
+ }
+ }
+
+ if (is_add)
+ {
+ vec_add2 (dm->outside_fibs, outside_fib, 1);
+ outside_fib->refcount = 1;
+ outside_fib->fib_index = new_fib_index;
+ }
+}
+
+static clib_error_t *
+det44_init (vlib_main_t * vm)
+{
+ det44_main_t *dm = &det44_main;
+ ip4_table_bind_callback_t cb;
+ vlib_node_t *node;
+
+ clib_memset (dm, 0, sizeof (*dm));
+
+ dm->ip4_main = &ip4_main;
+ dm->log_class = vlib_log_register_class ("det44", 0);
+
+ node = vlib_get_node_by_name (vm, (u8 *) "det44-in2out");
+ dm->in2out_node_index = node->index;
+ node = vlib_get_node_by_name (vm, (u8 *) "det44-out2in");
+ dm->out2in_node_index = node->index;
+
+ dm->fib_src_hi = fib_source_allocate ("det44-hi",
+ FIB_SOURCE_PRIORITY_HI,
+ FIB_SOURCE_BH_SIMPLE);
+ dm->fib_src_low = fib_source_allocate ("det44-low",
+ FIB_SOURCE_PRIORITY_LOW,
+ FIB_SOURCE_BH_SIMPLE);
+
+ cb.function = det44_update_outside_fib;
+ cb.function_opaque = 0;
+ vec_add1 (dm->ip4_main->table_bind_callbacks, cb);
+
+ det44_reset_timeouts ();
+ return det44_api_hookup (vm);
+}
+
+VLIB_INIT_FUNCTION (det44_init);
+
+u8 *
+format_det44_session_state (u8 * s, va_list * args)
+{
+ u32 i = va_arg (*args, u32);
+ u8 *t = 0;
+
+ switch (i)
+ {
+#define _(v, N, str) case DET44_SESSION_##N: t = (u8 *) str; break;
+ foreach_det44_session_state
+#undef _
+ default:
+ t = format (t, "unknown");
+ }
+ s = format (s, "%s", t);
+ return s;
+}
+
+u8 *
+format_det_map_ses (u8 * s, va_list * args)
+{
+ snat_det_map_t *det_map = va_arg (*args, snat_det_map_t *);
+ ip4_address_t in_addr, out_addr;
+ u32 in_offset, out_offset;
+ snat_det_session_t *ses = va_arg (*args, snat_det_session_t *);
+ u32 *i = va_arg (*args, u32 *);
+
+ u32 user_index = *i / DET44_SES_PER_USER;
+ in_addr.as_u32 =
+ clib_host_to_net_u32 (clib_net_to_host_u32 (det_map->in_addr.as_u32) +
+ user_index);
+ in_offset =
+ clib_net_to_host_u32 (in_addr.as_u32) -
+ clib_net_to_host_u32 (det_map->in_addr.as_u32);
+ out_offset = in_offset / det_map->sharing_ratio;
+ out_addr.as_u32 =
+ clib_host_to_net_u32 (clib_net_to_host_u32 (det_map->out_addr.as_u32) +
+ out_offset);
+ s =
+ format (s,
+ "in %U:%d out %U:%d external host %U:%d state: %U expire: %d\n",
+ format_ip4_address, &in_addr, clib_net_to_host_u16 (ses->in_port),
+ format_ip4_address, &out_addr,
+ clib_net_to_host_u16 (ses->out.out_port), format_ip4_address,
+ &ses->out.ext_host_addr,
+ clib_net_to_host_u16 (ses->out.ext_host_port),
+ format_det44_session_state, ses->state, ses->expire);
+
+ return s;
+}
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */