/* * encap.c : L2TPv3 tunnel encapsulation * * Copyright (c) 2013 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 <vppinfra/error.h> #include <vppinfra/hash.h> #include <vnet/vnet.h> #include <vnet/ip/ip.h> #include <vnet/ethernet/ethernet.h> #include <vnet/l2tp/l2tp.h> /* Statistics (not really errors) */ #define foreach_l2t_encap_error \ _(NETWORK_TO_USER, "L2TP L2 network to user (ip6) pkts") \ _(LOOKUP_FAIL_TO_L3, "L2TP L2 session lookup failed pkts") \ _(ADMIN_DOWN, "L2TP tunnel is down") static char *l2t_encap_error_strings[] = { #define _(sym,string) string, foreach_l2t_encap_error #undef _ }; typedef enum { #define _(sym,str) L2T_ENCAP_ERROR_##sym, foreach_l2t_encap_error #undef _ L2T_ENCAP_N_ERROR, } l2t_encap_error_t; typedef enum { L2T_ENCAP_NEXT_DROP, L2T_ENCAP_NEXT_IP6_LOOKUP, L2T_ENCAP_N_NEXT, } l2t_encap_next_t; typedef struct { u32 cached_session_index; u32 cached_sw_if_index; vnet_main_t *vnet_main; } l2tp_encap_runtime_t; vlib_node_registration_t l2t_encap_node; #define NSTAGES 3 static inline void stage0 (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_buffer_t * b) { vlib_prefetch_buffer_header (b, STORE); CLIB_PREFETCH (b->data, 2 * CLIB_CACHE_LINE_BYTES, STORE); } static inline void stage1 (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_buffer_t * b) { l2tp_encap_runtime_t *rt = (void *) node->runtime_data; vnet_hw_interface_t *hi; u32 sw_if_index = vnet_buffer (b)->sw_if_index[VLIB_TX]; u32 session_index = rt->cached_session_index; if (PREDICT_FALSE (rt->cached_sw_if_index != sw_if_index)) { hi = vnet_get_sup_hw_interface (rt->vnet_main, sw_if_index); session_index = rt->cached_session_index = hi->dev_instance; rt->cached_sw_if_index = sw_if_index; } /* Remember mapping index, prefetch the mini counter */ vnet_buffer (b)->l2t.next_index = L2T_ENCAP_NEXT_IP6_LOOKUP; vnet_buffer (b)->l2t.session_index = session_index; /* $$$$ prefetch counter... */ } static inline u32 last_stage (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_buffer_t * b) { l2t_main_t *lm = &l2t_main; vlib_node_t *n = vlib_get_node (vm, l2t_encap_node.index); u32 node_counter_base_index = n->error_heap_index; vlib_error_main_t *em = &vm->error_main; l2tpv3_header_t *l2tp; u32 session_index; u32 counter_index; l2t_session_t *s; ip6_header_t *ip6; u16 payload_length; u32 next_index = L2T_ENCAP_NEXT_IP6_LOOKUP; /* Other-than-output pkt? We're done... */ if (vnet_buffer (b)->l2t.next_index != L2T_ENCAP_NEXT_IP6_LOOKUP) return vnet_buffer (b)->l2t.next_index; em->counters[node_counter_base_index + L2T_ENCAP_ERROR_NETWORK_TO_USER] += 1; session_index = vnet_buffer (b)->l2t.session_index; counter_index = session_index_to_counter_index (session_index, SESSION_COUNTER_NETWORK_TO_USER); /* per-mapping byte stats include the ethernet header */ vlib_increment_combined_counter (&lm->counter_main, vlib_get_thread_index (), counter_index, 1 /* packet_increment */ , vlib_buffer_length_in_chain (vm, b)); s = pool_elt_at_index (lm->sessions, session_index); vnet_buffer (b)->sw_if_index[VLIB_TX] = s->encap_fib_index; /* Paint on an l2tpv3 hdr */ vlib_buffer_advance (b, -(s->l2tp_hdr_size)); l2tp = vlib_buffer_get_current (b); l2tp->session_id = s->remote_session_id; l2tp->cookie = s->remote_cookie; if (PREDICT_FALSE (s->l2_sublayer_present)) { l2tp->l2_specific_sublayer = 0; } /* Paint on an ip6 header */ vlib_buffer_advance (b, -(sizeof (*ip6))); ip6 = vlib_buffer_get_current (b); if (PREDICT_FALSE (!(s->admin_up))) { b->error = node->errors[L2T_ENCAP_ERROR_ADMIN_DOWN]; next_index = L2T_ENCAP_NEXT_DROP; goto done; } ip6->ip_version_traffic_class_and_flow_label = clib_host_to_net_u32 (0x6 << 28); /* calculate ip6 payload length */ payload_length = vlib_buffer_length_in_chain (vm, b); payload_length -= sizeof (*ip6); ip6->payload_length = clib_host_to_net_u16 (payload_length); ip6->protocol = IP_PROTOCOL_L2TP; ip6->hop_limit = 0xff; ip6->src_address.as_u64[0] = s->our_address.as_u64[0]; ip6->src_address.as_u64[1] = s->our_address.as_u64[1]; ip6->dst_address.as_u64[0] = s->client_address.as_u64[0]; ip6->dst_address.as_u64[1] = s->client_address.as_u64[1]; done: if (PREDICT_FALSE (b->flags & VLIB_BUFFER_IS_TRACED)) { l2t_trace_t *t = vlib_add_trace (vm, node, b, sizeof (*t)); t->is_user_to_network = 0; t->our_address.as_u64[0] = ip6->src_address.as_u64[0]; t->our_address.as_u64[1] = ip6->src_address.as_u64[1]; t->client_address.as_u64[0] = ip6->dst_address.as_u64[0]; t->client_address.as_u64[1] = ip6->dst_address.as_u64[1]; t->session_index = session_index; } return next_index; } #include <vnet/pipeline.h> uword l2t_encap_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame) { return dispatch_pipeline (vm, node, frame); } /* *INDENT-OFF* */ VLIB_REGISTER_NODE (l2t_encap_node) = { .function = l2t_encap_node_fn, .name = "l2tp-encap", .vector_size = sizeof (u32), .format_trace = format_l2t_trace, .type = VLIB_NODE_TYPE_INTERNAL, .runtime_data_bytes = sizeof (l2tp_encap_runtime_t), .n_errors = ARRAY_LEN(l2t_encap_error_strings), .error_strings = l2t_encap_error_strings, .n_next_nodes = L2T_ENCAP_N_NEXT, /* add dispositions here */ .next_nodes = { [L2T_ENCAP_NEXT_IP6_LOOKUP] = "ip6-lookup", [L2T_ENCAP_NEXT_DROP] = "error-drop", }, }; /* *INDENT-ON* */ VLIB_NODE_FUNCTION_MULTIARCH (l2t_encap_node, l2t_encap_node_fn); void l2tp_encap_init (vlib_main_t * vm) { l2tp_encap_runtime_t *rt; rt = vlib_node_get_runtime_data (vm, l2t_encap_node.index); rt->vnet_main = vnet_get_main (); rt->cached_sw_if_index = (u32) ~ 0; rt->cached_session_index = (u32) ~ 0; } /* * fd.io coding-style-patch-verification: ON * * Local Variables: * eval: (c-set-style "gnu") * End: */