diff options
Diffstat (limited to 'src/plugins/l2tp/encap.c')
| -rw-r--r-- | src/plugins/l2tp/encap.c | 235 |
1 files changed, 235 insertions, 0 deletions
diff --git a/src/plugins/l2tp/encap.c b/src/plugins/l2tp/encap.c new file mode 100644 index 00000000000..fbb5fc6ea46 --- /dev/null +++ b/src/plugins/l2tp/encap.c @@ -0,0 +1,235 @@ +/* + * 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 <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; + +extern 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> + +VLIB_NODE_FN (l2t_encap_node) (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) = { + .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* */ + +#ifndef CLIB_MARCH_VARIANT +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; +} +#endif /* CLIB_MARCH_VARIANT */ + +/* + * fd.io coding-style-patch-verification: ON + * + * Local Variables: + * eval: (c-set-style "gnu") + * End: + */ |