From 34af0ccf5cf27d8a72119626d2d009222e4ff0a6 Mon Sep 17 00:00:00 2001 From: Dave Barach Date: Wed, 21 Aug 2019 19:23:00 -0400 Subject: dns: make the dns name resolver a plugin Type: refactor Signed-off-by: Dave Barach Change-Id: I823c2cd307a4613653a2d20f564dda062d4da31b --- src/plugins/dns/reply_node.c | 227 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 227 insertions(+) create mode 100644 src/plugins/dns/reply_node.c (limited to 'src/plugins/dns/reply_node.c') diff --git a/src/plugins/dns/reply_node.c b/src/plugins/dns/reply_node.c new file mode 100644 index 00000000000..5d7e735e885 --- /dev/null +++ b/src/plugins/dns/reply_node.c @@ -0,0 +1,227 @@ +/* + * 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 + +#include +#include + +vlib_node_registration_t dns46_reply_node; + +typedef struct +{ + u32 pool_index; + u32 disposition; +} dns46_reply_trace_t; + +/* packet trace format function */ +static u8 * +format_dns46_reply_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 *); + dns46_reply_trace_t *t = va_arg (*args, dns46_reply_trace_t *); + + s = format (s, "DNS46_REPLY: pool index %d, disposition %d", + t->pool_index, t->disposition); + return s; +} + +vlib_node_registration_t dns46_reply_node; + +static char *dns46_reply_error_strings[] = { +#define _(sym,string) string, + foreach_dns46_reply_error +#undef _ +}; + +typedef enum +{ + DNS46_REPLY_NEXT_DROP, + DNS46_REPLY_NEXT_PUNT, + DNS46_REPLY_N_NEXT, +} dns46_reply_next_t; + +static uword +dns46_reply_node_fn (vlib_main_t * vm, + vlib_node_runtime_t * node, vlib_frame_t * frame) +{ + u32 n_left_from, *from, *to_next; + dns46_reply_next_t next_index; + dns_main_t *dm = &dns_main; + + 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); + +#if 0 + while (n_left_from >= 4 && n_left_to_next >= 2) + { + u32 next0 = DNS46_REPLY_NEXT_INTERFACE_OUTPUT; + u32 next1 = DNS46_REPLY_NEXT_INTERFACE_OUTPUT; + u32 sw_if_index0, sw_if_index1; + u8 tmp0[6], tmp1[6]; + ethernet_header_t *en0, *en1; + u32 bi0, bi1; + vlib_buffer_t *b0, *b1; + + /* Prefetch next iteration. */ + { + vlib_buffer_t *p2, *p3; + + p2 = vlib_get_buffer (vm, from[2]); + p3 = vlib_get_buffer (vm, from[3]); + + vlib_prefetch_buffer_header (p2, LOAD); + vlib_prefetch_buffer_header (p3, LOAD); + + CLIB_PREFETCH (p2->data, CLIB_CACHE_LINE_BYTES, STORE); + CLIB_PREFETCH (p3->data, CLIB_CACHE_LINE_BYTES, STORE); + } + + /* speculatively enqueue b0 and b1 to the current next frame */ + to_next[0] = bi0 = from[0]; + to_next[1] = bi1 = from[1]; + from += 2; + to_next += 2; + n_left_from -= 2; + n_left_to_next -= 2; + + b0 = vlib_get_buffer (vm, bi0); + b1 = vlib_get_buffer (vm, bi1); + + /* $$$$$ End of processing 2 x packets $$$$$ */ + + if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE))) + { + if (b0->flags & VLIB_BUFFER_IS_TRACED) + { + dns46_reply_trace_t *t = + vlib_add_trace (vm, node, b0, sizeof (*t)); + t->sw_if_index = sw_if_index0; + t->next_index = next0; + } + if (b1->flags & VLIB_BUFFER_IS_TRACED) + { + dns46_reply_trace_t *t = + vlib_add_trace (vm, node, b1, sizeof (*t)); + t->sw_if_index = sw_if_index1; + t->next_index = next1; + } + } + + /* verify speculative enqueues, maybe switch current next frame */ + vlib_validate_buffer_enqueue_x2 (vm, node, next_index, + to_next, n_left_to_next, + bi0, bi1, next0, next1); + } +#endif + + while (n_left_from > 0 && n_left_to_next > 0) + { + u32 bi0; + vlib_buffer_t *b0; + u32 next0 = DNS46_REPLY_NEXT_DROP; + dns_header_t *d0; + u32 pool_index0 = ~0; + u32 error0 = 0; + u8 *resp0 = 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); + d0 = vlib_buffer_get_current (b0); + if (PREDICT_FALSE (dm->is_enabled == 0)) + { + next0 = DNS46_REPLY_NEXT_PUNT; + error0 = DNS46_REPLY_ERROR_DISABLED; + goto done0; + } + + pool_index0 = clib_host_to_net_u16 (d0->id); + + /* Save the reply */ + vec_validate (resp0, vlib_buffer_length_in_chain (vm, b0) - 1); + clib_memcpy_fast (resp0, d0, vlib_buffer_length_in_chain (vm, b0)); + + /* + * Deal with everything in process ctx on the main thread + */ + vlib_process_signal_event_mt (vm, dm->resolver_process_node_index, + DNS_RESOLVER_EVENT_RESOLVED, + (uword) resp0); + error0 = DNS46_REPLY_ERROR_PROCESSED; + + done0: + b0->error = node->errors[error0]; + + if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE) + && (b0->flags & VLIB_BUFFER_IS_TRACED))) + { + dns46_reply_trace_t *t = + vlib_add_trace (vm, node, b0, sizeof (*t)); + t->disposition = error0; + t->pool_index = pool_index0; + } + + /* 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 (dns46_reply_node) = +{ + .function = dns46_reply_node_fn, + .name = "dns46_reply", + .vector_size = sizeof (u32), + .format_trace = format_dns46_reply_trace, + .type = VLIB_NODE_TYPE_INTERNAL, + .n_errors = ARRAY_LEN (dns46_reply_error_strings), + .error_strings = dns46_reply_error_strings, + .n_next_nodes = DNS46_REPLY_N_NEXT, + .next_nodes = { + [DNS46_REPLY_NEXT_DROP] = "error-drop", + [DNS46_REPLY_NEXT_PUNT] = "error-punt", + }, +}; +/* *INDENT-ON* */ + +/* + * fd.io coding-style-patch-verification: ON + * + * Local Variables: + * eval: (c-set-style "gnu") + * End: + */ -- cgit 1.2.3-korg