Line data Source code
1 : /*
2 : * Copyright (c) 2017 Cisco and/or its affiliates.
3 : * Licensed under the Apache License, Version 2.0 (the "License");
4 : * you may not use this file except in compliance with the License.
5 : * You may obtain a copy of the License at:
6 : *
7 : * http://www.apache.org/licenses/LICENSE-2.0
8 : *
9 : * Unless required by applicable law or agreed to in writing, software
10 : * distributed under the License is distributed on an "AS IS" BASIS,
11 : * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 : * See the License for the specific language governing permissions and
13 : * limitations under the License.
14 : */
15 :
16 : #include <dns/dns.h>
17 :
18 : #include <vlib/vlib.h>
19 : #include <vnet/vnet.h>
20 :
21 : vlib_node_registration_t dns46_request_node;
22 :
23 : typedef struct
24 : {
25 : u32 pool_index;
26 : u32 disposition;
27 : } dns46_request_trace_t;
28 :
29 : /* packet trace format function */
30 : static u8 *
31 1 : format_dns46_request_trace (u8 * s, va_list * args)
32 : {
33 1 : CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
34 1 : CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
35 1 : dns46_request_trace_t *t = va_arg (*args, dns46_request_trace_t *);
36 :
37 1 : s = format (s, "DNS46_REPLY: pool index %d, disposition %d",
38 : t->pool_index, t->disposition);
39 1 : return s;
40 : }
41 :
42 : vlib_node_registration_t dns46_request_node;
43 :
44 : static char *dns46_request_error_strings[] = {
45 : #define _(sym,string) string,
46 : foreach_dns46_request_error
47 : #undef _
48 : };
49 :
50 : typedef enum
51 : {
52 : DNS46_REQUEST_NEXT_DROP,
53 : DNS46_REQUEST_NEXT_IP_LOOKUP,
54 : DNS46_REQUEST_NEXT_PUNT,
55 : DNS46_REQUEST_N_NEXT,
56 : } dns46_request_next_t;
57 :
58 : static uword
59 1 : dns46_request_inline (vlib_main_t * vm,
60 : vlib_node_runtime_t * node, vlib_frame_t * frame,
61 : int is_ip6)
62 : {
63 : u32 n_left_from, *from, *to_next;
64 : dns46_request_next_t next_index;
65 1 : dns_main_t *dm = &dns_main;
66 :
67 1 : from = vlib_frame_vector_args (frame);
68 1 : n_left_from = frame->n_vectors;
69 1 : next_index = node->cached_next_index;
70 :
71 2 : while (n_left_from > 0)
72 : {
73 : u32 n_left_to_next;
74 :
75 1 : vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
76 :
77 : #if 0
78 : while (n_left_from >= 4 && n_left_to_next >= 2)
79 : {
80 : u32 next0 = DNS46_REQUEST_NEXT_INTERFACE_OUTPUT;
81 : u32 next1 = DNS46_REQUEST_NEXT_INTERFACE_OUTPUT;
82 : u32 sw_if_index0, sw_if_index1;
83 : u8 tmp0[6], tmp1[6];
84 : ethernet_header_t *en0, *en1;
85 : u32 bi0, bi1;
86 : vlib_buffer_t *b0, *b1;
87 :
88 : /* Prefetch next iteration. */
89 : {
90 : vlib_buffer_t *p2, *p3;
91 :
92 : p2 = vlib_get_buffer (vm, from[2]);
93 : p3 = vlib_get_buffer (vm, from[3]);
94 :
95 : vlib_prefetch_buffer_header (p2, LOAD);
96 : vlib_prefetch_buffer_header (p3, LOAD);
97 :
98 : clib_prefetch_store (p2->data);
99 : clib_prefetch_store (p3->data);
100 : }
101 :
102 : /* speculatively enqueue b0 and b1 to the current next frame */
103 : to_next[0] = bi0 = from[0];
104 : to_next[1] = bi1 = from[1];
105 : from += 2;
106 : to_next += 2;
107 : n_left_from -= 2;
108 : n_left_to_next -= 2;
109 :
110 : b0 = vlib_get_buffer (vm, bi0);
111 : b1 = vlib_get_buffer (vm, bi1);
112 :
113 : /* $$$$$ End of processing 2 x packets $$$$$ */
114 :
115 : if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)))
116 : {
117 : if (b0->flags & VLIB_BUFFER_IS_TRACED)
118 : {
119 : dns46_request_trace_t *t =
120 : vlib_add_trace (vm, node, b0, sizeof (*t));
121 : t->sw_if_index = sw_if_index0;
122 : t->next_index = next0;
123 : }
124 : if (b1->flags & VLIB_BUFFER_IS_TRACED)
125 : {
126 : dns46_request_trace_t *t =
127 : vlib_add_trace (vm, node, b1, sizeof (*t));
128 : t->sw_if_index = sw_if_index1;
129 : t->next_index = next1;
130 : }
131 : }
132 :
133 : /* verify speculative enqueues, maybe switch current next frame */
134 : vlib_validate_buffer_enqueue_x2 (vm, node, next_index,
135 : to_next, n_left_to_next,
136 : bi0, bi1, next0, next1);
137 : }
138 : #endif
139 :
140 3 : while (n_left_from > 0 && n_left_to_next > 0)
141 : {
142 : u32 bi0;
143 : vlib_buffer_t *b0;
144 2 : u32 next0 = DNS46_REQUEST_NEXT_DROP;
145 2 : u32 error0 = DNS46_REQUEST_ERROR_NONE;
146 : udp_header_t *u0;
147 : dns_header_t *d0;
148 : dns_query_t *q0;
149 2 : ip4_header_t *ip40 = 0;
150 2 : ip6_header_t *ip60 = 0;
151 : dns_cache_entry_t *ep0;
152 2 : dns_pending_request_t _t0, *t0 = &_t0;
153 : u16 flags0;
154 2 : u32 pool_index0 = ~0;
155 : u8 *name0;
156 : u8 *label0;
157 :
158 : /* speculatively enqueue b0 to the current next frame */
159 2 : bi0 = from[0];
160 2 : to_next[0] = bi0;
161 2 : from += 1;
162 2 : to_next += 1;
163 2 : n_left_from -= 1;
164 2 : n_left_to_next -= 1;
165 :
166 2 : b0 = vlib_get_buffer (vm, bi0);
167 2 : d0 = vlib_buffer_get_current (b0);
168 2 : u0 = (udp_header_t *) ((u8 *) d0 - sizeof (*u0));
169 :
170 2 : if (PREDICT_FALSE (dm->is_enabled == 0))
171 : {
172 0 : next0 = DNS46_REQUEST_NEXT_PUNT;
173 0 : goto done0;
174 : }
175 :
176 2 : if (is_ip6)
177 : {
178 0 : ip60 = (ip6_header_t *) (((u8 *) u0) - sizeof (ip6_header_t));
179 0 : next0 = DNS46_REQUEST_NEXT_DROP;
180 0 : error0 = DNS46_REQUEST_ERROR_UNIMPLEMENTED;
181 0 : goto done0;
182 : }
183 : else
184 : {
185 2 : ip40 = (ip4_header_t *) (((u8 *) u0) - sizeof (ip4_header_t));
186 2 : if (ip40->ip_version_and_header_length != 0x45)
187 : {
188 0 : error0 = DNS46_REQUEST_ERROR_IP_OPTIONS;
189 0 : goto done0;
190 : }
191 : }
192 : /* Parse through the DNS request */
193 2 : flags0 = clib_net_to_host_u16 (d0->flags);
194 :
195 : /* Requests only */
196 2 : if (flags0 & DNS_QR)
197 : {
198 0 : next0 = DNS46_REQUEST_NEXT_DROP;
199 0 : error0 = DNS46_REQUEST_ERROR_BAD_REQUEST;
200 0 : goto done0;
201 : }
202 2 : if (clib_net_to_host_u16 (d0->qdcount) != 1)
203 : {
204 0 : next0 = DNS46_REQUEST_NEXT_DROP;
205 0 : error0 = DNS46_REQUEST_ERROR_TOO_MANY_REQUESTS;
206 0 : goto done0;
207 : }
208 :
209 2 : label0 = (u8 *) (d0 + 1);
210 :
211 2 : name0 = vnet_dns_labels_to_name (label0, (u8 *) d0, (u8 **) & q0);
212 :
213 2 : t0->request_type = DNS_PEER_PENDING_NAME_TO_IP;
214 :
215 : /*
216 : * See if this is a reverse lookup. Both ip4 and ip6 reverse
217 : * requests end with ".arpa"
218 : */
219 2 : if (PREDICT_TRUE (vec_len (name0) > 5))
220 : {
221 2 : u8 *aptr0 = name0 + vec_len (name0) - 5;
222 :
223 2 : if (!memcmp (aptr0, ".arpa", 5))
224 0 : t0->request_type = DNS_PEER_PENDING_IP_TO_NAME;
225 : }
226 :
227 2 : t0->client_index = ~0;
228 2 : t0->is_ip6 = is_ip6;
229 2 : t0->dst_port = u0->src_port;
230 2 : t0->id = d0->id;
231 2 : t0->name = name0;
232 2 : if (is_ip6)
233 0 : clib_memcpy_fast (t0->dst_address, ip60->src_address.as_u8,
234 : sizeof (ip6_address_t));
235 : else
236 2 : clib_memcpy_fast (t0->dst_address, ip40->src_address.as_u8,
237 : sizeof (ip4_address_t));
238 :
239 : /*
240 : * vnet_dns_labels_to_name produces a non NULL terminated vector
241 : * vnet_dns_resolve_name expects a C-string.
242 : */
243 2 : vec_add1 (name0, 0);
244 2 : vnet_dns_resolve_name (vm, dm, name0, t0, &ep0);
245 :
246 2 : if (ep0)
247 : {
248 1 : if (is_ip6)
249 0 : vnet_send_dns6_reply (vm, dm, t0, ep0, b0);
250 : else
251 1 : vnet_send_dns4_reply (vm, dm, t0, ep0, b0);
252 1 : next0 = DNS46_REQUEST_NEXT_IP_LOOKUP;
253 : }
254 : else
255 : {
256 1 : error0 = DNS46_REQUEST_ERROR_RESOLUTION_REQUIRED;
257 : }
258 :
259 2 : done0:
260 2 : b0->error = node->errors[error0];
261 :
262 2 : if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
263 : && (b0->flags & VLIB_BUFFER_IS_TRACED)))
264 : {
265 : dns46_request_trace_t *t =
266 1 : vlib_add_trace (vm, node, b0, sizeof (*t));
267 1 : t->disposition = error0;
268 1 : t->pool_index = pool_index0;
269 : }
270 :
271 : /* verify speculative enqueue, maybe switch current next frame */
272 2 : vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
273 : to_next, n_left_to_next,
274 : bi0, next0);
275 : }
276 :
277 1 : vlib_put_next_frame (vm, node, next_index, n_left_to_next);
278 : }
279 :
280 1 : return frame->n_vectors;
281 : }
282 :
283 : static uword
284 1 : dns4_request_node_fn (vlib_main_t * vm,
285 : vlib_node_runtime_t * node, vlib_frame_t * frame)
286 : {
287 :
288 1 : return dns46_request_inline (vm, node, frame, 0 /* is_ip6 */ );
289 : }
290 :
291 : /* *INDENT-OFF* */
292 151532 : VLIB_REGISTER_NODE (dns4_request_node) =
293 : {
294 : .function = dns4_request_node_fn,
295 : .name = "dns4-request",
296 : .vector_size = sizeof (u32),
297 : .format_trace = format_dns46_request_trace,
298 : .type = VLIB_NODE_TYPE_INTERNAL,
299 : .n_errors = ARRAY_LEN (dns46_request_error_strings),
300 : .error_strings = dns46_request_error_strings,
301 : .n_next_nodes = DNS46_REQUEST_N_NEXT,
302 : .next_nodes = {
303 : [DNS46_REQUEST_NEXT_DROP] = "error-drop",
304 : [DNS46_REQUEST_NEXT_PUNT] = "error-punt",
305 : [DNS46_REQUEST_NEXT_IP_LOOKUP] = "ip4-lookup",
306 : },
307 : };
308 : /* *INDENT-ON* */
309 :
310 : static uword
311 0 : dns6_request_node_fn (vlib_main_t * vm,
312 : vlib_node_runtime_t * node, vlib_frame_t * frame)
313 : {
314 :
315 0 : return dns46_request_inline (vm, node, frame, 1 /* is_ip6 */ );
316 : }
317 :
318 : /* *INDENT-OFF* */
319 151532 : VLIB_REGISTER_NODE (dns6_request_node) =
320 : {
321 : .function = dns6_request_node_fn,
322 : .name = "dns6-request",
323 : .vector_size = sizeof (u32),
324 : .format_trace = format_dns46_request_trace,
325 : .type = VLIB_NODE_TYPE_INTERNAL,
326 : .n_errors = ARRAY_LEN (dns46_request_error_strings),
327 : .error_strings = dns46_request_error_strings,
328 : .n_next_nodes = DNS46_REQUEST_N_NEXT,
329 : .next_nodes = {
330 : [DNS46_REQUEST_NEXT_DROP] = "error-drop",
331 : [DNS46_REQUEST_NEXT_PUNT] = "error-punt",
332 : [DNS46_REQUEST_NEXT_IP_LOOKUP] = "ip6-lookup",
333 : },
334 : };
335 : /* *INDENT-ON* */
336 :
337 : /*
338 : * fd.io coding-style-patch-verification: ON
339 : *
340 : * Local Variables:
341 : * eval: (c-set-style "gnu")
342 : * End:
343 : */
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