/* * trace_classify.h - Use the classifier to decide if a packet is traced * * Copyright (c) 2019 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 <vlib/vlib.h> #include <vnet/vnet.h> #include <vppinfra/error.h> #include <vnet/classify/vnet_classify.h> /** @file trace_classify.h * Use the vpp classifier to decide whether to trace packets */ /** @brief vnet_is_packet_traced * @param vlib_buffer_t *b - packet to classify * @param int func - 0 => use classifier w/ supplied table index * @param u32 classify_table_index - classifier table index * @return 0 => no trace, 1 => trace, -1 => error */ static inline int vnet_is_packet_traced_inline (vlib_buffer_t * b, u32 classify_table_index, int func) { vnet_classify_main_t *vcm = &vnet_classify_main; vnet_classify_table_t *t; vnet_classify_entry_t *e; u64 hash; /*$$$ add custom classifiers here, if any */ if (func != 0) return -1; /* This will happen... */ if (pool_is_free_index (vcm->tables, classify_table_index)) return -1; /* Get the table */ t = pool_elt_at_index (vcm->tables, classify_table_index); /* Hash the packet */ hash = vnet_classify_hash_packet (t, vlib_buffer_get_current (b)); /* See if there's a matching entry */ e = vnet_classify_find_entry (t, vlib_buffer_get_current (b), hash, 0 /* time = 0, disables hit-counter */ ); /* Hit means trace the packet... */ if (e) { /* Manual hit accounting */ e->hits++; return 1; } /* * Look for a hit in a less-specific table. * Performance hint: for this use-case, don't go there. */ while (1) { /* Most likely, we're done right now */ if (PREDICT_TRUE (t->next_table_index == ~0)) return 0; t = pool_elt_at_index (vcm->tables, t->next_table_index); /* Compute hash for this table */ hash = vnet_classify_hash_packet (t, vlib_buffer_get_current (b)); /* See if there's a matching entry */ e = vnet_classify_find_entry (t, vlib_buffer_get_current (b), hash, 0 /* time = 0, disables hit-counter */ ); if (e) { /* Manual hit accounting */ e->hits++; return 1; } } /* NOTREACHED */ } /* * fd.io coding-style-patch-verification: ON * * Local Variables: * eval: (c-set-style "gnu") * End: */