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-rw-r--r--src/plugins/nat/nat44_classify.c516
1 files changed, 516 insertions, 0 deletions
diff --git a/src/plugins/nat/nat44_classify.c b/src/plugins/nat/nat44_classify.c
new file mode 100644
index 00000000000..0e9863c02ac
--- /dev/null
+++ b/src/plugins/nat/nat44_classify.c
@@ -0,0 +1,516 @@
+/*
+ * Copyright (c) 2018 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 Classify for one armed NAT44 (in+out interface)
+ */
+
+#include <vlib/vlib.h>
+#include <vnet/vnet.h>
+#include <vnet/fib/ip4_fib.h>
+#include <nat/nat.h>
+#include <nat/nat_reass.h>
+#include <nat/nat_inlines.h>
+
+vlib_node_registration_t nat44_classify_node;
+vlib_node_registration_t nat44_ed_classify_node;
+vlib_node_registration_t nat44_det_classify_node;
+vlib_node_registration_t nat44_handoff_classify_node;
+
+#define foreach_nat44_classify_error \
+_(MAX_REASS, "Maximum reassemblies exceeded") \
+_(MAX_FRAG, "Maximum fragments per reassembly exceeded")
+
+typedef enum
+{
+#define _(sym,str) NAT44_CLASSIFY_ERROR_##sym,
+ foreach_nat44_classify_error
+#undef _
+ NAT44_CLASSIFY_N_ERROR,
+} nat44_classify_error_t;
+
+static char *nat44_classify_error_strings[] = {
+#define _(sym,string) string,
+ foreach_nat44_classify_error
+#undef _
+};
+
+typedef enum
+{
+ NAT44_CLASSIFY_NEXT_IN2OUT,
+ NAT44_CLASSIFY_NEXT_OUT2IN,
+ NAT44_CLASSIFY_NEXT_DROP,
+ NAT44_CLASSIFY_N_NEXT,
+} nat44_classify_next_t;
+
+typedef struct
+{
+ u8 next_in2out;
+ u8 cached;
+} nat44_classify_trace_t;
+
+static u8 *
+format_nat44_classify_trace (u8 * s, va_list * args)
+{
+ CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
+ CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
+ nat44_classify_trace_t *t = va_arg (*args, nat44_classify_trace_t *);
+ char *next;
+
+ if (t->cached)
+ s = format (s, "nat44-classify: fragment cached");
+ else
+ {
+ next = t->next_in2out ? "nat44-in2out" : "nat44-out2in";
+ s = format (s, "nat44-classify: next %s", next);
+ }
+
+ return s;
+}
+
+static inline uword
+nat44_classify_node_fn_inline (vlib_main_t * vm,
+ vlib_node_runtime_t * node,
+ vlib_frame_t * frame, int is_ed)
+{
+ u32 n_left_from, *from, *to_next;
+ nat44_classify_next_t next_index;
+ snat_main_t *sm = &snat_main;
+ snat_static_mapping_t *m;
+ u32 thread_index = vm->thread_index;
+ snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index];
+ u32 *fragments_to_drop = 0;
+ u32 *fragments_to_loopback = 0;
+
+ from = vlib_frame_vector_args (frame);
+ n_left_from = frame->n_vectors;
+ next_index = node->cached_next_index;
+
+ while (n_left_from > 0)
+ {
+ u32 n_left_to_next;
+
+ vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
+
+ while (n_left_from > 0 && n_left_to_next > 0)
+ {
+ u32 bi0;
+ vlib_buffer_t *b0;
+ u32 next0 = NAT44_CLASSIFY_NEXT_IN2OUT, sw_if_index0, rx_fib_index0;
+ ip4_header_t *ip0;
+ snat_address_t *ap;
+ snat_session_key_t m_key0;
+ clib_bihash_kv_8_8_t kv0, value0;
+ clib_bihash_kv_16_8_t ed_kv0, ed_value0;
+ udp_header_t *udp0;
+ nat_reass_ip4_t *reass0;
+ u8 cached0 = 0;
+
+ /* speculatively enqueue b0 to the current next frame */
+ bi0 = from[0];
+ to_next[0] = bi0;
+ from += 1;
+ to_next += 1;
+ n_left_from -= 1;
+ n_left_to_next -= 1;
+
+ b0 = vlib_get_buffer (vm, bi0);
+ ip0 = vlib_buffer_get_current (b0);
+ udp0 = ip4_next_header (ip0);
+
+ if (is_ed && ip0->protocol != IP_PROTOCOL_ICMP)
+ {
+ if (!ip4_is_fragment (ip0) || ip4_is_first_fragment (ip0))
+ {
+ /* process leading fragment/whole packet (with L4 header) */
+ sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
+ rx_fib_index0 =
+ fib_table_get_index_for_sw_if_index (FIB_PROTOCOL_IP4,
+ sw_if_index0);
+ make_ed_kv (&ed_kv0, &ip0->src_address, &ip0->dst_address,
+ ip0->protocol, rx_fib_index0, udp0->src_port,
+ udp0->dst_port);
+ if (ip4_is_fragment (ip0))
+ {
+ reass0 = nat_ip4_reass_find_or_create (ip0->src_address,
+ ip0->dst_address,
+ ip0->fragment_id,
+ ip0->protocol,
+ 1,
+ &fragments_to_drop);
+ if (PREDICT_FALSE (!reass0))
+ {
+ next0 = NAT44_CLASSIFY_NEXT_DROP;
+ b0->error =
+ node->errors[NAT44_CLASSIFY_ERROR_MAX_REASS];
+ nat_log_notice ("maximum reassemblies exceeded");
+ goto enqueue0;
+ }
+ if (!clib_bihash_search_16_8 (&tsm->in2out_ed, &ed_kv0,
+ &ed_value0))
+ {
+ /* session exists so classify as IN2OUT,
+ * save this information for future fragments and set
+ * past fragments to be looped over and reprocessed */
+ reass0->sess_index = ed_value0.value;
+ reass0->classify_next =
+ NAT_REASS_IP4_CLASSIFY_NEXT_IN2OUT;
+ nat_ip4_reass_get_frags (reass0,
+ &fragments_to_loopback);
+ goto enqueue0;
+ }
+ else
+ {
+ /* session doesn't exist so continue in the code,
+ * save this information for future fragments and set
+ * past fragments to be looped over and reprocessed */
+ reass0->flags |=
+ NAT_REASS_FLAG_CLASSIFY_ED_CONTINUE;
+ nat_ip4_reass_get_frags (reass0,
+ &fragments_to_loopback);
+ }
+ }
+ else
+ {
+ /* process whole packet */
+ if (!clib_bihash_search_16_8 (&tsm->in2out_ed, &ed_kv0,
+ &ed_value0))
+ goto enqueue0;
+ /* session doesn't exist so continue in code */
+ }
+ }
+ else
+ {
+ /* process non-first fragment */
+ reass0 = nat_ip4_reass_find_or_create (ip0->src_address,
+ ip0->dst_address,
+ ip0->fragment_id,
+ ip0->protocol,
+ 1,
+ &fragments_to_drop);
+ if (PREDICT_FALSE (!reass0))
+ {
+ next0 = NAT44_CLASSIFY_NEXT_DROP;
+ b0->error =
+ node->errors[NAT44_CLASSIFY_ERROR_MAX_REASS];
+ nat_log_notice ("maximum reassemblies exceeded");
+ goto enqueue0;
+ }
+ /* check if first fragment has arrived */
+ if (reass0->classify_next == NAT_REASS_IP4_CLASSIFY_NONE &&
+ !(reass0->flags & NAT_REASS_FLAG_CLASSIFY_ED_CONTINUE))
+ {
+ /* first fragment still hasn't arrived, cache this fragment */
+ if (nat_ip4_reass_add_fragment (reass0, bi0,
+ &fragments_to_drop))
+ {
+ b0->error =
+ node->errors[NAT44_CLASSIFY_ERROR_MAX_FRAG];
+ nat_log_notice
+ ("maximum fragments per reassembly exceeded");
+ next0 = NAT44_CLASSIFY_NEXT_DROP;
+ goto enqueue0;
+ }
+ cached0 = 1;
+ goto enqueue0;
+ }
+ if (reass0->classify_next ==
+ NAT_REASS_IP4_CLASSIFY_NEXT_IN2OUT)
+ goto enqueue0;
+ /* flag NAT_REASS_FLAG_CLASSIFY_ED_CONTINUE is set
+ * so keep the default next0 and continue in code to
+ * potentially find other classification for this packet */
+ }
+ }
+
+ /* *INDENT-OFF* */
+ vec_foreach (ap, sm->addresses)
+ {
+ if (ip0->dst_address.as_u32 == ap->addr.as_u32)
+ {
+ next0 = NAT44_CLASSIFY_NEXT_OUT2IN;
+ goto enqueue0;
+ }
+ }
+ /* *INDENT-ON* */
+
+ if (PREDICT_FALSE (pool_elts (sm->static_mappings)))
+ {
+ m_key0.addr = ip0->dst_address;
+ m_key0.port = 0;
+ m_key0.protocol = 0;
+ m_key0.fib_index = 0;
+ kv0.key = m_key0.as_u64;
+ /* try to classify the fragment based on IP header alone */
+ if (!clib_bihash_search_8_8 (&sm->static_mapping_by_external,
+ &kv0, &value0))
+ {
+ m = pool_elt_at_index (sm->static_mappings, value0.value);
+ if (m->local_addr.as_u32 != m->external_addr.as_u32)
+ next0 = NAT44_CLASSIFY_NEXT_OUT2IN;
+ goto enqueue0;
+ }
+ if (!ip4_is_fragment (ip0) || ip4_is_first_fragment (ip0))
+ {
+ /* process leading fragment/whole packet (with L4 header) */
+ m_key0.port = clib_net_to_host_u16 (udp0->dst_port);
+ m_key0.protocol = ip_proto_to_snat_proto (ip0->protocol);
+ kv0.key = m_key0.as_u64;
+ if (!clib_bihash_search_8_8
+ (&sm->static_mapping_by_external, &kv0, &value0))
+ {
+ m =
+ pool_elt_at_index (sm->static_mappings, value0.value);
+ if (m->local_addr.as_u32 != m->external_addr.as_u32)
+ next0 = NAT44_CLASSIFY_NEXT_OUT2IN;
+ }
+ if (ip4_is_fragment (ip0))
+ {
+ reass0 = nat_ip4_reass_find_or_create (ip0->src_address,
+ ip0->dst_address,
+ ip0->fragment_id,
+ ip0->protocol,
+ 1,
+ &fragments_to_drop);
+ if (PREDICT_FALSE (!reass0))
+ {
+ next0 = NAT44_CLASSIFY_NEXT_DROP;
+ b0->error =
+ node->errors[NAT44_CLASSIFY_ERROR_MAX_REASS];
+ nat_log_notice ("maximum reassemblies exceeded");
+ goto enqueue0;
+ }
+ /* save classification for future fragments and set past
+ * fragments to be looped over and reprocessed */
+ if (next0 == NAT44_CLASSIFY_NEXT_OUT2IN)
+ reass0->classify_next =
+ NAT_REASS_IP4_CLASSIFY_NEXT_OUT2IN;
+ else
+ reass0->classify_next =
+ NAT_REASS_IP4_CLASSIFY_NEXT_IN2OUT;
+ nat_ip4_reass_get_frags (reass0,
+ &fragments_to_loopback);
+ }
+ }
+ else
+ {
+ /* process non-first fragment */
+ reass0 = nat_ip4_reass_find_or_create (ip0->src_address,
+ ip0->dst_address,
+ ip0->fragment_id,
+ ip0->protocol,
+ 1,
+ &fragments_to_drop);
+ if (PREDICT_FALSE (!reass0))
+ {
+ next0 = NAT44_CLASSIFY_NEXT_DROP;
+ b0->error =
+ node->errors[NAT44_CLASSIFY_ERROR_MAX_REASS];
+ nat_log_notice ("maximum reassemblies exceeded");
+ goto enqueue0;
+ }
+ if (reass0->classify_next == NAT_REASS_IP4_CLASSIFY_NONE)
+ /* first fragment still hasn't arrived */
+ {
+ if (nat_ip4_reass_add_fragment (reass0, bi0,
+ &fragments_to_drop))
+ {
+ b0->error =
+ node->errors[NAT44_CLASSIFY_ERROR_MAX_FRAG];
+ nat_log_notice
+ ("maximum fragments per reassembly exceeded");
+ next0 = NAT44_CLASSIFY_NEXT_DROP;
+ goto enqueue0;
+ }
+ cached0 = 1;
+ goto enqueue0;
+ }
+ else if (reass0->classify_next ==
+ NAT_REASS_IP4_CLASSIFY_NEXT_OUT2IN)
+ next0 = NAT44_CLASSIFY_NEXT_OUT2IN;
+ else if (reass0->classify_next ==
+ NAT_REASS_IP4_CLASSIFY_NEXT_IN2OUT)
+ next0 = NAT44_CLASSIFY_NEXT_IN2OUT;
+ }
+ }
+
+ enqueue0:
+ if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
+ && (b0->flags & VLIB_BUFFER_IS_TRACED)))
+ {
+ nat44_classify_trace_t *t =
+ vlib_add_trace (vm, node, b0, sizeof (*t));
+ t->cached = cached0;
+ if (!cached0)
+ t->next_in2out = next0 == NAT44_CLASSIFY_NEXT_IN2OUT ? 1 : 0;
+ }
+
+ if (cached0)
+ {
+ n_left_to_next++;
+ to_next--;
+ }
+ else
+ /* verify speculative enqueue, maybe switch current next frame */
+ vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
+ to_next, n_left_to_next,
+ bi0, next0);
+
+ if (n_left_from == 0 && vec_len (fragments_to_loopback))
+ {
+ from = vlib_frame_vector_args (frame);
+ u32 len = vec_len (fragments_to_loopback);
+ if (len <= VLIB_FRAME_SIZE)
+ {
+ clib_memcpy (from, fragments_to_loopback,
+ sizeof (u32) * len);
+ n_left_from = len;
+ vec_reset_length (fragments_to_loopback);
+ }
+ else
+ {
+ clib_memcpy (from,
+ fragments_to_loopback + (len -
+ VLIB_FRAME_SIZE),
+ sizeof (u32) * VLIB_FRAME_SIZE);
+ n_left_from = VLIB_FRAME_SIZE;
+ _vec_len (fragments_to_loopback) = len - VLIB_FRAME_SIZE;
+ }
+ }
+ }
+
+ vlib_put_next_frame (vm, node, next_index, n_left_to_next);
+ }
+
+ nat_send_all_to_node (vm, fragments_to_drop, node, 0,
+ NAT44_CLASSIFY_NEXT_DROP);
+
+ vec_free (fragments_to_drop);
+
+ return frame->n_vectors;
+}
+
+static uword
+nat44_classify_node_fn (vlib_main_t * vm,
+ vlib_node_runtime_t * node, vlib_frame_t * frame)
+{
+ return nat44_classify_node_fn_inline (vm, node, frame, 0);
+}
+
+/* *INDENT-OFF* */
+VLIB_REGISTER_NODE (nat44_classify_node) = {
+ .function = nat44_classify_node_fn,
+ .name = "nat44-classify",
+ .vector_size = sizeof (u32),
+ .format_trace = format_nat44_classify_trace,
+ .type = VLIB_NODE_TYPE_INTERNAL,
+ .n_errors = ARRAY_LEN(nat44_classify_error_strings),
+ .error_strings = nat44_classify_error_strings,
+ .n_next_nodes = NAT44_CLASSIFY_N_NEXT,
+ .next_nodes = {
+ [NAT44_CLASSIFY_NEXT_IN2OUT] = "nat44-in2out",
+ [NAT44_CLASSIFY_NEXT_OUT2IN] = "nat44-out2in",
+ [NAT44_CLASSIFY_NEXT_DROP] = "error-drop",
+ },
+};
+/* *INDENT-ON* */
+
+VLIB_NODE_FUNCTION_MULTIARCH (nat44_classify_node, nat44_classify_node_fn);
+static uword
+nat44_ed_classify_node_fn (vlib_main_t * vm,
+ vlib_node_runtime_t * node, vlib_frame_t * frame)
+{
+ return nat44_classify_node_fn_inline (vm, node, frame, 1);
+}
+
+/* *INDENT-OFF* */
+VLIB_REGISTER_NODE (nat44_ed_classify_node) = {
+ .function = nat44_ed_classify_node_fn,
+ .name = "nat44-ed-classify",
+ .vector_size = sizeof (u32),
+ .format_trace = format_nat44_classify_trace,
+ .type = VLIB_NODE_TYPE_INTERNAL,
+ .n_next_nodes = NAT44_CLASSIFY_N_NEXT,
+ .next_nodes = {
+ [NAT44_CLASSIFY_NEXT_IN2OUT] = "nat44-ed-in2out",
+ [NAT44_CLASSIFY_NEXT_OUT2IN] = "nat44-ed-out2in",
+ [NAT44_CLASSIFY_NEXT_DROP] = "error-drop",
+ },
+};
+/* *INDENT-ON* */
+
+VLIB_NODE_FUNCTION_MULTIARCH (nat44_ed_classify_node,
+ nat44_ed_classify_node_fn);
+
+static uword
+nat44_det_classify_node_fn (vlib_main_t * vm,
+ vlib_node_runtime_t * node, vlib_frame_t * frame)
+{
+ return nat44_classify_node_fn_inline (vm, node, frame, 0);
+}
+
+/* *INDENT-OFF* */
+VLIB_REGISTER_NODE (nat44_det_classify_node) = {
+ .function = nat44_det_classify_node_fn,
+ .name = "nat44-det-classify",
+ .vector_size = sizeof (u32),
+ .format_trace = format_nat44_classify_trace,
+ .type = VLIB_NODE_TYPE_INTERNAL,
+ .n_next_nodes = NAT44_CLASSIFY_N_NEXT,
+ .next_nodes = {
+ [NAT44_CLASSIFY_NEXT_IN2OUT] = "nat44-det-in2out",
+ [NAT44_CLASSIFY_NEXT_OUT2IN] = "nat44-det-out2in",
+ [NAT44_CLASSIFY_NEXT_DROP] = "error-drop",
+ },
+};
+/* *INDENT-ON* */
+
+VLIB_NODE_FUNCTION_MULTIARCH (nat44_det_classify_node,
+ nat44_det_classify_node_fn);
+
+static uword
+nat44_handoff_classify_node_fn (vlib_main_t * vm,
+ vlib_node_runtime_t * node,
+ vlib_frame_t * frame)
+{
+ return nat44_classify_node_fn_inline (vm, node, frame, 0);
+}
+
+/* *INDENT-OFF* */
+VLIB_REGISTER_NODE (nat44_handoff_classify_node) = {
+ .function = nat44_handoff_classify_node_fn,
+ .name = "nat44-handoff-classify",
+ .vector_size = sizeof (u32),
+ .format_trace = format_nat44_classify_trace,
+ .type = VLIB_NODE_TYPE_INTERNAL,
+ .n_next_nodes = NAT44_CLASSIFY_N_NEXT,
+ .next_nodes = {
+ [NAT44_CLASSIFY_NEXT_IN2OUT] = "nat44-in2out-worker-handoff",
+ [NAT44_CLASSIFY_NEXT_OUT2IN] = "nat44-out2in-worker-handoff",
+ [NAT44_CLASSIFY_NEXT_DROP] = "error-drop",
+ },
+};
+
+VLIB_NODE_FUNCTION_MULTIARCH (nat44_handoff_classify_node,
+ nat44_handoff_classify_node_fn);
+/* *INDENT-ON* */
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */