diff options
Diffstat (limited to 'src/plugins/dns/request_node.c')
| -rw-r--r-- | src/plugins/dns/request_node.c | 344 |
1 files changed, 344 insertions, 0 deletions
diff --git a/src/plugins/dns/request_node.c b/src/plugins/dns/request_node.c new file mode 100644 index 00000000000..d26e579cf47 --- /dev/null +++ b/src/plugins/dns/request_node.c @@ -0,0 +1,344 @@ +/* + * 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 (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_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 (dm, name0, t0, &ep0); + + if (ep0) + { + if (is_ip6) + vnet_send_dns6_reply (dm, t0, ep0, b0); + else + vnet_send_dns4_reply (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: + */ |