2 * Copyright (c) 2011-2016 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:
7 * http://www.apache.org/licenses/LICENSE-2.0
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.
15 #include <vnet/cdp/cdp_node.h>
19 #define DEBUG_TLV_DUMP 0 /* 1=> dump TLV's to stdout while processing them */
21 /* Reliable multicast messages we use to keep peers updated */
22 mc_serialize_msg_t serialize_cdp_neighbor_msg;
23 mc_serialize_msg_t serialize_cdp_keepalive_msg;
26 * ported from an unspecified Cisco cdp implementation.
27 * Compute / return in HOST byte order. 0 => good checksum.
30 cdp_checksum (void *p, int count)
45 sum += *(char *) data;
49 sum = (sum & 0xFFFF) + (sum >> 16);
56 /* TLV handler table */
65 static tlv_handler_t tlv_handlers[];
67 /* Display a generic TLV as a set of hex bytes */
69 format_generic_tlv (u8 * s, va_list * va)
71 cdp_tlv_t *t = va_arg (*va, cdp_tlv_t *);
72 tlv_handler_t *h = &tlv_handlers[t->t];
74 s = format (s, "%s(%d): %U\n", h->name,
75 t->t, format_hex_bytes, t->v, t->l - sizeof (*t));
79 /* Ignore / skip a TLV we don't support */
81 process_generic_tlv (cdp_main_t * cm, cdp_neighbor_t * n, cdp_tlv_t * t)
83 #if DEBUG_TLV_DUMP > 0
84 fformat (stdout, "%U", format_generic_tlv, t);
87 return CDP_ERROR_NONE;
90 /* print a text tlv */
92 format_text_tlv (u8 * s, va_list * va)
94 cdp_tlv_t *t = va_arg (*va, cdp_tlv_t *);
95 tlv_handler_t *h = &tlv_handlers[t->t];
98 s = format (s, "%s(%d): ", h->name, t->t);
100 for (i = 0; i < (t->l - sizeof (*t)); i++)
101 vec_add1 (s, t->v[i]);
107 #if DEBUG_TLV_DUMP == 0
108 /* gcc warning be gone */
109 CLIB_UNUSED (static cdp_error_t
110 process_text_tlv (cdp_main_t * cm, cdp_neighbor_t * n,
114 /* process / skip a generic text TLV that we don't support */
116 process_text_tlv (cdp_main_t * cm, cdp_neighbor_t * n, cdp_tlv_t * t)
118 #if DEBUG_TLV_DUMP > 0
119 fformat (stdout, "%U\n", format_text_tlv, t);
122 return CDP_ERROR_NONE;
125 /* per-TLV format function definitions */
126 #define format_unused_tlv format_generic_tlv
127 #define format_device_name_tlv format_text_tlv
128 #define format_address_tlv format_generic_tlv
129 #define format_port_id_tlv format_text_tlv
130 #define format_capabilities_tlv format_generic_tlv
131 #define format_version_tlv format_text_tlv
132 #define format_platform_tlv format_text_tlv
133 #define format_ipprefix_tlv format_generic_tlv
134 #define format_hello_tlv format_generic_tlv
135 #define format_vtp_domain_tlv format_generic_tlv
136 #define format_native_vlan_tlv format_generic_tlv
137 #define format_duplex_tlv format_generic_tlv
138 #define format_appl_vlan_tlv format_generic_tlv
139 #define format_trigger_tlv format_generic_tlv
140 #define format_power_tlv format_generic_tlv
141 #define format_mtu_tlv format_generic_tlv
142 #define format_trust_tlv format_generic_tlv
143 #define format_cos_tlv format_generic_tlv
144 #define format_sysname_tlv format_generic_tlv
145 #define format_sysobject_tlv format_generic_tlv
146 #define format_mgmt_addr_tlv format_generic_tlv
147 #define format_physical_loc_tlv format_generic_tlv
148 #define format_mgmt_addr2_tlv format_generic_tlv
149 #define format_power_requested_tlv format_generic_tlv
150 #define format_power_available_tlv format_generic_tlv
151 #define format_port_unidirectional_tlv format_generic_tlv
152 #define format_unknown_28_tlv format_generic_tlv
153 #define format_energywise_tlv format_generic_tlv
154 #define format_unknown_30_tlv format_generic_tlv
155 #define format_spare_poe_tlv format_generic_tlv
157 /* tlv ID=0 is a mistake */
159 process_unused_tlv (cdp_main_t * cm, cdp_neighbor_t * n, cdp_tlv_t * t)
161 return CDP_ERROR_BAD_TLV;
164 /* list of text TLV's that we snapshoot */
165 #define foreach_text_to_struct_tlv \
166 _(device_name,DEBUG_TLV_DUMP) \
167 _(version,DEBUG_TLV_DUMP) \
168 _(platform,DEBUG_TLV_DUMP) \
169 _(port_id,DEBUG_TLV_DUMP)
173 cdp_error_t process_##z##_tlv (cdp_main_t *cm, cdp_neighbor_t *n, \
178 fformat(stdout, "%U\n", format_text_tlv, t); \
181 _vec_len(n->z) = 0; \
183 for (i = 0; i < (t->l - sizeof (*t)); i++) \
184 vec_add1(n->z, t->v[i]); \
188 return CDP_ERROR_NONE; \
191 foreach_text_to_struct_tlv
193 #define process_address_tlv process_generic_tlv
194 #define process_capabilities_tlv process_generic_tlv
195 #define process_ipprefix_tlv process_generic_tlv
196 #define process_hello_tlv process_generic_tlv
197 #define process_vtp_domain_tlv process_generic_tlv
198 #define process_native_vlan_tlv process_generic_tlv
199 #define process_duplex_tlv process_generic_tlv
200 #define process_appl_vlan_tlv process_generic_tlv
201 #define process_trigger_tlv process_generic_tlv
202 #define process_power_tlv process_generic_tlv
203 #define process_mtu_tlv process_generic_tlv
204 #define process_trust_tlv process_generic_tlv
205 #define process_cos_tlv process_generic_tlv
206 #define process_sysname_tlv process_generic_tlv
207 #define process_sysobject_tlv process_generic_tlv
208 #define process_mgmt_addr_tlv process_generic_tlv
209 #define process_physical_loc_tlv process_generic_tlv
210 #define process_mgmt_addr2_tlv process_generic_tlv
211 #define process_power_requested_tlv process_generic_tlv
212 #define process_power_available_tlv process_generic_tlv
213 #define process_port_unidirectional_tlv process_generic_tlv
214 #define process_unknown_28_tlv process_generic_tlv
215 #define process_energywise_tlv process_generic_tlv
216 #define process_unknown_30_tlv process_generic_tlv
217 #define process_spare_poe_tlv process_generic_tlv
218 static tlv_handler_t tlv_handlers[] = {
219 #define _(a) {#a, CDP_TLV_##a, format_##a##_tlv, process_##a##_tlv},
224 #if DEBUG_TLV_DUMP == 0
225 CLIB_UNUSED (static u8 * format_cdp_hdr (u8 * s, va_list * va));
229 format_cdp_hdr (u8 * s, va_list * va)
231 cdp_hdr_t *h = va_arg (*va, cdp_hdr_t *);
233 s = format (s, "version %d, ttl %d(secs), cksum 0x%04x\n",
234 h->version, h->ttl, h->checksum);
239 process_cdp_hdr (cdp_main_t * cm, cdp_neighbor_t * n, cdp_hdr_t * h)
241 #if DEBUG_TLV_DUMP > 0
242 fformat (stdout, "%U", format_cdp_hdr, h);
245 if (h->version != 1 && h->version != 2)
246 return CDP_ERROR_PROTOCOL_VERSION;
248 n->ttl_in_seconds = h->ttl;
250 return CDP_ERROR_NONE;
253 /* scan a cdp packet; header, then tlv's */
255 cdp_packet_scan (cdp_main_t * cm, cdp_neighbor_t * n)
257 u8 *cur = n->last_rx_pkt;
260 cdp_error_t e = CDP_ERROR_NONE;
261 tlv_handler_t *handler;
262 cdp_error_t (*fp) (cdp_main_t *, cdp_neighbor_t *, cdp_tlv_t *);
263 u16 computed_checksum;
265 computed_checksum = cdp_checksum (cur, vec_len (cur));
267 if (computed_checksum)
268 return CDP_ERROR_CHECKSUM;
270 h = (cdp_hdr_t *) cur;
272 e = process_cdp_hdr (cm, n, h);
276 cur = (u8 *) (h + 1);
278 while (cur < n->last_rx_pkt + vec_len (n->last_rx_pkt) - 1)
280 tlv = (cdp_tlv_t *) cur;
281 tlv->t = ntohs (tlv->t);
282 tlv->l = ntohs (tlv->l);
283 if (tlv->t >= ARRAY_LEN (tlv_handlers))
284 return CDP_ERROR_BAD_TLV;
285 handler = &tlv_handlers[tlv->t];
286 fp = handler->process;
287 e = (*fp) (cm, n, tlv);
290 /* tlv length includes (t, l) */
294 return CDP_ERROR_NONE;
301 cdp_input (vlib_main_t * vm, vlib_buffer_t * b0, u32 bi0)
303 cdp_main_t *cm = &cdp_main;
307 uword last_packet_signature;
309 /* find or create a neighbor pool entry for the (sw) interface
310 upon which we received this pkt */
311 p = hash_get (cm->neighbor_by_sw_if_index,
312 vnet_buffer (b0)->sw_if_index[VLIB_RX]);
316 pool_get (cm->neighbors, n);
317 memset (n, 0, sizeof (*n));
318 n->sw_if_index = vnet_buffer (b0)->sw_if_index[VLIB_RX];
319 n->packet_template_index = (u8) ~ 0;
320 hash_set (cm->neighbor_by_sw_if_index, n->sw_if_index,
325 n = pool_elt_at_index (cm->neighbors, p[0]);
329 * typical clib idiom. Don't repeatedly allocate and free
330 * the per-neighbor rx buffer. Reset its apparent length to zero
335 _vec_len (n->last_rx_pkt) = 0;
337 /* cdp disabled on this interface, we're done */
339 return CDP_ERROR_DISABLED;
342 * Make sure the per-neighbor rx buffer is big enough to hold
343 * the data we're about to copy
345 vec_validate (n->last_rx_pkt, vlib_buffer_length_in_chain (vm, b0) - 1);
348 * Coalesce / copy e the buffer chain into the per-neighbor
351 nbytes = vlib_buffer_contents (vm, bi0, n->last_rx_pkt);
352 ASSERT (nbytes <= vec_len (n->last_rx_pkt));
355 * Compute Jenkins hash of the new packet, decide if we need to
356 * actually parse through the TLV's. CDP packets are all identical,
357 * so unless we time out the peer, we don't need to process the packet.
359 last_packet_signature =
360 hash_memory (n->last_rx_pkt, vec_len (n->last_rx_pkt), 0xd00b);
362 if (n->last_packet_signature_valid &&
363 n->last_packet_signature == last_packet_signature)
365 e = CDP_ERROR_CACHE_HIT;
369 /* Actually scan the packet */
370 e = cdp_packet_scan (cm, n);
371 n->last_packet_signature_valid = 1;
372 n->last_packet_signature = last_packet_signature;
375 if (e == CDP_ERROR_NONE)
377 n->last_heard = vlib_time_now (vm);
384 * setup neighbor hash table
386 static clib_error_t *
387 cdp_init (vlib_main_t * vm)
390 cdp_main_t *cm = &cdp_main;
391 void vnet_cdp_node_reference (void);
393 vnet_cdp_node_reference ();
395 if ((error = vlib_call_init_function (vm, cdp_periodic_init)))
399 cm->vnet_main = vnet_get_main ();
400 cm->neighbor_by_sw_if_index = hash_create (0, sizeof (uword));
405 VLIB_INIT_FUNCTION (cdp_init);
409 format_cdp_neighbors (u8 * s, va_list * va)
411 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*va, vlib_main_t *);
412 cdp_main_t *cm = va_arg (*va, cdp_main_t *);
413 vnet_main_t *vnm = &vnet_main;
415 vnet_hw_interface_t *hw;
418 "%=25s %=15s %=25s %=10s\n",
419 "Our Port", "Peer System", "Peer Port", "Last Heard");
422 pool_foreach (n, cm->neighbors,
424 hw = vnet_get_sup_hw_interface (vnm, n->sw_if_index);
426 if (n->disabled == 0)
427 s = format (s, "%=25s %=15s %=25s %=10.1f\n",
428 hw->name, n->device_name, n->port_id,
436 static clib_error_t *
437 show_cdp (vlib_main_t * vm,
438 unformat_input_t * input, vlib_cli_command_t * cmd)
440 cdp_main_t *cm = &cdp_main;
442 vlib_cli_output (vm, "%U\n", format_cdp_neighbors, vm, cm);
448 VLIB_CLI_COMMAND (show_cdp_command, static) = {
450 .short_help = "Show cdp command",
451 .function = show_cdp,
457 * packet trace format function, very similar to
458 * cdp_packet_scan except that we call the per TLV format
459 * functions instead of the per TLV processing functions
462 cdp_input_format_trace (u8 * s, va_list * args)
464 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
465 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
466 cdp_input_trace_t *t = va_arg (*args, cdp_input_trace_t *);
470 tlv_handler_t *handler;
471 u8 *(*fp) (cdp_tlv_t *);
475 h = (cdp_hdr_t *) cur;
476 s = format (s, "%U", format_cdp_hdr, h);
478 cur = (u8 *) (h + 1);
480 while (cur < t->data + t->len)
482 tlv = (cdp_tlv_t *) cur;
483 tlv->t = ntohs (tlv->t);
484 tlv->l = ntohs (tlv->l);
485 if (tlv->t >= ARRAY_LEN (tlv_handlers))
487 s = format (s, "BAD_TLV\n");
490 handler = &tlv_handlers[tlv->t];
491 fp = handler->format;
492 s = format (s, " %U", fp, tlv);
493 /* tlv length includes (t, l) */
501 * fd.io coding-style-patch-verification: ON
504 * eval: (c-set-style "gnu")