/* * 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 <dns/dns.h> #include <vlib/vlib.h> #include <vnet/vnet.h> vlib_node_registration_t dns46_request_node; typedef struct { u32 pool_index; u32 disposition; } dns46_request_trace_t; /* packet trace format function */ static u8 * format_dns46_request_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_request_trace_t *t = va_arg (*args, dns46_request_trace_t *); s = format (s, "DNS46_REPLY: pool index %d, disposition %d", t->pool_index, t->disposition); return s; } vlib_node_registration_t dns46_request_node; static char *dns46_request_error_strings[] = { #define _(sym,string) string, foreach_dns46_request_error #undef _ }; typedef enum { DNS46_REQUEST_NEXT_DROP, DNS46_REQUEST_NEXT_IP_LOOKUP, DNS46_REQUEST_NEXT_PUNT, DNS46_REQUEST_N_NEXT, } dns46_request_next_t; static uword dns46_request_inline (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame, int is_ip6) { u32 n_left_from, *from, *to_next; dns46_request_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_REQUEST_NEXT_INTERFACE_OUTPUT; u32 next1 = DNS46_REQUEST_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_store (p2->data); clib_prefetch_store (p3->data); } /* 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_request_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_request_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_REQUEST_NEXT_DROP; u32 error0 = DNS46_REQUEST_ERROR_NONE; udp_header_t *u0; dns_header_t *d0; dns_query_t *q0; ip4_header_t *ip40 = 0; ip6_header_t *ip60 = 0; dns_cache_entry_t *ep0; dns_pending_request_t _t0, *t0 = &_t0; u16 flags0; u32 pool_index0 = ~0; u8 *name0; u8 *label0; /* 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); u0 = (udp_header_t *) ((u8 *) d0 - sizeof (*u0)); if (PREDICT_FALSE (dm->is_enabled == 0)) { next0 = DNS46_REQUEST_NEXT_PUNT; goto done0; } if (is_ip6) { ip60 = (ip6_header_t *) (((u8 *) u0) - sizeof (ip6_header_t)); next0 = DNS46_REQUEST_NEXT_DROP; error0 = DNS46_REQUEST_ERROR_UNIMPLEMENTED; goto done0; } else { ip40 = (ip4_header_t *) (((u8 *) u0) - sizeof (ip4_header_t)); if (ip40->ip_version_and_header_length != 0x45) { error0 = DNS46_REQUEST_ERROR_IP_OPTIONS; goto done0; } } /* Parse through the DNS request */ flags0 = clib_net_to_host_u16 (d0->flags); /* Requests only */ if (flags0 & DNS_QR) { next0 = DNS46_REQUEST_NEXT_DROP; error0 = DNS46_REQUEST_ERROR_BAD_REQUEST; goto done0; } if (clib_net_to_host_u16 (d0->qdcount) != 1) { next0 = DNS46_REQUEST_NEXT_DROP; error0 = DNS46_REQUEST_ERROR_TOO_MANY_REQUESTS; goto done0; } label0 = (u8 *) (d0 + 1); /* * vnet_dns_labels_to_name produces a non NULL terminated vector * vnet_dns_resolve_name expects a C-string. */ name0 = vnet_dns_labels_to_name (label0, (u8 *) d0, (u8 **) & q0); vec_add1 (name0, 0); _vec_len (name0) -= 1; t0->request_type = DNS_PEER_PENDING_NAME_TO_IP; /* * See if this is a reverse lookup. Both ip4 and ip6 reverse * requests end with ".arpa" */ if (PREDICT_TRUE (vec_len (name0) > 5)) { u8 *aptr0 = name0 + vec_len (name0) - 5; if (!memcmp (aptr0, ".arpa", 5)) t0->request_type = DNS_PEER_PENDING_IP_TO_NAME; } t0->client_index = ~0; t0->is_ip6 = is_ip6; t0->dst_port = u0->src_port; t0->id = d0->id; t0->name = name0; if (is_ip6) clib_memcpy_fast (t0->dst_address, ip60->src_address.as_u8, sizeof (ip6_address_t)); else clib_memcpy_fast (t0->dst_address, ip40->src_address.as_u8, sizeof (ip4_address_t)); vnet_dns_resolve_name (vm, dm, name0, t0, &ep0); if (ep0) { if (is_ip6) vnet_send_dns6_reply (vm, dm, t0, ep0, b0); else vnet_send_dns4_reply (vm, dm, t0, ep0, b0); next0 = DNS46_REQUEST_NEXT_IP_LOOKUP; } else { error0 = DNS46_REQUEST_ERROR_RESOLUTION_REQUIRED; } done0: b0->error = node->errors[error0]; if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE) && (b0->flags & VLIB_BUFFER_IS_TRACED))) { dns46_request_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; } static uword dns4_request_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame) { return dns46_request_inline (vm, node, frame, 0 /* is_ip6 */ ); } /* *INDENT-OFF* */ VLIB_REGISTER_NODE (dns4_request_node) = { .function = dns4_request_node_fn, .name = "dns4-request", .vector_size = sizeof (u32), .format_trace = format_dns46_request_trace, .type = VLIB_NODE_TYPE_INTERNAL, .n_errors = ARRAY_LEN (dns46_request_error_strings), .error_strings = dns46_request_error_strings, .n_next_nodes = DNS46_REQUEST_N_NEXT, .next_nodes = { [DNS46_REQUEST_NEXT_DROP] = "error-drop", [DNS46_REQUEST_NEXT_PUNT] = "error-punt", [DNS46_REQUEST_NEXT_IP_LOOKUP] = "ip4-lookup", }, }; /* *INDENT-ON* */ static uword dns6_request_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame) { return dns46_request_inline (vm, node, frame, 1 /* is_ip6 */ ); } /* *INDENT-OFF* */ VLIB_REGISTER_NODE (dns6_request_node) = { .function = dns6_request_node_fn, .name = "dns6-request", .vector_size = sizeof (u32), .format_trace = format_dns46_request_trace, .type = VLIB_NODE_TYPE_INTERNAL, .n_errors = ARRAY_LEN (dns46_request_error_strings), .error_strings = dns46_request_error_strings, .n_next_nodes = DNS46_REQUEST_N_NEXT, .next_nodes = { [DNS46_REQUEST_NEXT_DROP] = "error-drop", [DNS46_REQUEST_NEXT_PUNT] = "error-punt", [DNS46_REQUEST_NEXT_IP_LOOKUP] = "ip6-lookup", }, }; /* *INDENT-ON* */ /* * fd.io coding-style-patch-verification: ON * * Local Variables: * eval: (c-set-style "gnu") * End: */