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authorMatus Fabian <matfabia@cisco.com>2017-11-06 05:04:53 -0800
committerOle Trøan <otroan@employees.org>2017-11-07 11:52:39 +0000
commit8ebe62536223e5a8d827b2b870cbd57aa34fd7ef (patch)
treef4ab30aa41a7a26bb6068e7f0f441930cc7774bb /src/plugins/nat/dslite_out2in.c
parent5917939256af392914d8a648de0c3287042ddbf6 (diff)
NAT: DS-Lite (VPP-1040)
Dual-Stack Lite enables a broadband service provider to share IPv4 addresses among customers by combining two well-known technologies: IPv4-in-IPv6 and NAT. Change-Id: I039740f8548c623cd1ac89b8ecda1a6cc4aafb9c Signed-off-by: Matus Fabian <matfabia@cisco.com>
Diffstat (limited to 'src/plugins/nat/dslite_out2in.c')
-rw-r--r--src/plugins/nat/dslite_out2in.c297
1 files changed, 297 insertions, 0 deletions
diff --git a/src/plugins/nat/dslite_out2in.c b/src/plugins/nat/dslite_out2in.c
new file mode 100644
index 00000000000..802b2a91544
--- /dev/null
+++ b/src/plugins/nat/dslite_out2in.c
@@ -0,0 +1,297 @@
+/*
+ * Copyright (c) 2017 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.
+ */
+#include <nat/dslite.h>
+
+vlib_node_registration_t dslite_out2in_node;
+
+typedef enum
+{
+ DSLITE_OUT2IN_NEXT_IP4_LOOKUP,
+ DSLITE_OUT2IN_NEXT_IP6_LOOKUP,
+ DSLITE_OUT2IN_NEXT_DROP,
+ DSLITE_OUT2IN_N_NEXT,
+} dslite_out2in_next_t;
+
+static char *dslite_out2in_error_strings[] = {
+#define _(sym,string) string,
+ foreach_dslite_error
+#undef _
+};
+
+static inline u32
+dslite_icmp_out2in (dslite_main_t * dm, ip4_header_t * ip4,
+ dslite_session_t ** sp, u32 next, u8 * error,
+ u32 thread_index)
+{
+ dslite_session_t *s = 0;
+ icmp46_header_t *icmp = ip4_next_header (ip4);
+ clib_bihash_kv_8_8_t kv, value;
+ snat_session_key_t key;
+ u32 n = next;
+ icmp_echo_header_t *echo;
+ u32 new_addr, old_addr;
+ u16 old_id, new_id;
+ ip_csum_t sum;
+
+ echo = (icmp_echo_header_t *) (icmp + 1);
+
+ if (icmp_is_error_message (icmp) || (icmp->type != ICMP4_echo_reply))
+ {
+ n = DSLITE_OUT2IN_NEXT_DROP;
+ *error = DSLITE_ERROR_BAD_ICMP_TYPE;
+ goto done;
+ }
+
+ key.addr = ip4->dst_address;
+ key.port = echo->identifier;
+ key.protocol = SNAT_PROTOCOL_ICMP;
+ key.fib_index = 0;
+ kv.key = key.as_u64;
+
+ if (clib_bihash_search_8_8
+ (&dm->per_thread_data[thread_index].out2in, &kv, &value))
+ {
+ next = DSLITE_OUT2IN_NEXT_DROP;
+ *error = DSLITE_ERROR_NO_TRANSLATION;
+ goto done;
+ }
+ else
+ {
+ s =
+ pool_elt_at_index (dm->per_thread_data[thread_index].sessions,
+ value.value);
+ }
+
+ old_id = echo->identifier;
+ echo->identifier = new_id = s->in2out.port;
+ sum = icmp->checksum;
+ sum = ip_csum_update (sum, old_id, new_id, icmp_echo_header_t, identifier);
+ icmp->checksum = ip_csum_fold (sum);
+
+ old_addr = ip4->dst_address.as_u32;
+ ip4->dst_address = s->in2out.addr;
+ new_addr = ip4->dst_address.as_u32;
+
+ sum = ip4->checksum;
+ sum = ip_csum_update (sum, old_addr, new_addr, ip4_header_t, dst_address);
+ ip4->checksum = ip_csum_fold (sum);
+
+done:
+ *sp = s;
+ return n;
+}
+
+static uword
+dslite_out2in_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
+ vlib_frame_t * frame)
+{
+ u32 n_left_from, *from, *to_next;
+ dslite_out2in_next_t next_index;
+ vlib_node_runtime_t *error_node;
+ u32 thread_index = vlib_get_thread_index ();
+ f64 now = vlib_time_now (vm);
+ dslite_main_t *dm = &dslite_main;
+
+ error_node = vlib_node_get_runtime (vm, dslite_out2in_node.index);
+
+ 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 = DSLITE_OUT2IN_NEXT_IP6_LOOKUP;
+ u8 error0 = DSLITE_ERROR_OUT2IN;
+ ip4_header_t *ip40;
+ ip6_header_t *ip60;
+ u32 proto0;
+ udp_header_t *udp0;
+ tcp_header_t *tcp0;
+ clib_bihash_kv_8_8_t kv0, value0;
+ snat_session_key_t key0;
+ dslite_session_t *s0 = 0;
+ ip_csum_t sum0;
+ u32 new_addr0, old_addr0;
+ u16 new_port0, old_port0;
+
+ /* 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);
+ ip40 = vlib_buffer_get_current (b0);
+ proto0 = ip_proto_to_snat_proto (ip40->protocol);
+
+ if (PREDICT_FALSE (proto0 == ~0))
+ {
+ error0 = DSLITE_ERROR_UNSUPPORTED_PROTOCOL;
+ next0 = DSLITE_OUT2IN_NEXT_DROP;
+ goto trace0;
+ }
+
+ if (PREDICT_FALSE (proto0 == SNAT_PROTOCOL_ICMP))
+ {
+ next0 =
+ dslite_icmp_out2in (dm, ip40, &s0, next0, &error0,
+ thread_index);
+ if (PREDICT_FALSE (next0 == DSLITE_OUT2IN_NEXT_DROP))
+ goto trace0;
+
+ goto encap0;
+ }
+
+ udp0 = ip4_next_header (ip40);
+ tcp0 = (tcp_header_t *) udp0;
+
+ key0.addr = ip40->dst_address;
+ key0.port = udp0->dst_port;
+ key0.protocol = proto0;
+ key0.fib_index = 0;
+ kv0.key = key0.as_u64;
+
+ if (clib_bihash_search_8_8
+ (&dm->per_thread_data[thread_index].out2in, &kv0, &value0))
+ {
+ next0 = DSLITE_OUT2IN_NEXT_DROP;
+ error0 = DSLITE_ERROR_NO_TRANSLATION;
+ goto trace0;
+ }
+ else
+ {
+ s0 =
+ pool_elt_at_index (dm->per_thread_data[thread_index].sessions,
+ value0.value);
+ }
+
+ old_addr0 = ip40->dst_address.as_u32;
+ ip40->dst_address = s0->in2out.addr;
+ new_addr0 = ip40->dst_address.as_u32;
+
+ sum0 = ip40->checksum;
+ sum0 =
+ ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
+ dst_address);
+ ip40->checksum = ip_csum_fold (sum0);
+
+ if (PREDICT_TRUE (proto0 == SNAT_PROTOCOL_TCP))
+ {
+ old_port0 = tcp0->dst_port;
+ tcp0->dst_port = s0->in2out.port;
+ new_port0 = tcp0->dst_port;
+
+ sum0 = tcp0->checksum;
+ sum0 =
+ ip_csum_update (sum0, old_addr0, new_addr0, ip4_header_t,
+ dst_address);
+ sum0 =
+ ip_csum_update (sum0, old_port0, new_port0, ip4_header_t,
+ length);
+ tcp0->checksum = ip_csum_fold (sum0);
+ }
+ else
+ {
+ old_port0 = udp0->dst_port;
+ udp0->dst_port = s0->in2out.port;
+ udp0->checksum = 0;
+ }
+
+ encap0:
+ /* Construct IPv6 header */
+ vlib_buffer_advance (b0, -(sizeof (ip6_header_t)));
+ ip60 = vlib_buffer_get_current (b0);
+ ip60->ip_version_traffic_class_and_flow_label =
+ clib_host_to_net_u32 ((6 << 28) + (ip40->tos << 20));
+ ip60->payload_length = ip40->length;
+ ip60->protocol = IP_PROTOCOL_IP_IN_IP;
+ ip60->hop_limit = ip40->ttl;
+ ip60->src_address.as_u64[0] = dm->aftr_ip6_addr.as_u64[0];
+ ip60->src_address.as_u64[1] = dm->aftr_ip6_addr.as_u64[1];
+ ip60->dst_address.as_u64[0] = s0->in2out.softwire_id.as_u64[0];
+ ip60->dst_address.as_u64[1] = s0->in2out.softwire_id.as_u64[1];
+
+ /* Accounting */
+ s0->last_heard = now;
+ s0->total_pkts++;
+ s0->total_bytes += vlib_buffer_length_in_chain (vm, b0);
+ /* Per-B4 LRU list maintenance */
+ clib_dlist_remove (dm->per_thread_data[thread_index].list_pool,
+ s0->per_b4_index);
+ clib_dlist_addtail (dm->per_thread_data[thread_index].list_pool,
+ s0->per_b4_list_head_index, s0->per_b4_index);
+ trace0:
+ if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
+ && (b0->flags & VLIB_BUFFER_IS_TRACED)))
+ {
+ dslite_trace_t *t = vlib_add_trace (vm, node, b0, sizeof (*t));
+ t->next_index = next0;
+ t->session_index = ~0;
+ if (s0)
+ t->session_index =
+ s0 - dm->per_thread_data[thread_index].sessions;
+ }
+
+ b0->error = error_node->errors[error0];
+
+ /* 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);
+ }
+ vlib_put_next_frame (vm, node, next_index, n_left_to_next);
+ }
+
+ return frame->n_vectors;
+}
+
+/* *INDENT-OFF* */
+VLIB_REGISTER_NODE (dslite_out2in_node) = {
+ .function = dslite_out2in_node_fn,
+ .name = "dslite-out2in",
+ .vector_size = sizeof (u32),
+ .format_trace = format_dslite_trace,
+ .type = VLIB_NODE_TYPE_INTERNAL,
+ .n_errors = ARRAY_LEN (dslite_out2in_error_strings),
+ .error_strings = dslite_out2in_error_strings,
+ .n_next_nodes = DSLITE_OUT2IN_N_NEXT,
+ /* edit / add dispositions here */
+ .next_nodes = {
+ [DSLITE_OUT2IN_NEXT_DROP] = "error-drop",
+ [DSLITE_OUT2IN_NEXT_IP4_LOOKUP] = "ip4-lookup",
+ [DSLITE_OUT2IN_NEXT_IP6_LOOKUP] = "ip6-lookup",
+ },
+};
+/* *INDENT-ON* */
+
+VLIB_NODE_FUNCTION_MULTIARCH (dslite_out2in_node, dslite_out2in_node_fn);
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */