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/*
* Copyright (c) 2011-2018 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 <cdp/cdp.h>
#include <vnet/ethernet/packet.h>
/** \file
2 x CDP graph nodes: an "interior" node to process
incoming announcements, and a "process" node to periodically
send announcements.
The interior node is neither pipelined nor dual-looped, because
it would be very unusual to see more than one CDP packet in
a given input frame. So, it's a very simple / straightforward
example.
*/
/*
* packet counter strings
* Dump these counters via the "show error" CLI command
*/
static char *cdp_error_strings[] = {
#define _(sym,string) string,
foreach_cdp_error
#undef _
};
/*
* We actually send all cdp pkts to the "error" node after scanning
* them, so the graph node has only one next-index. The "error-drop"
* node automatically bumps our per-node packet counters for us.
*/
typedef enum
{
CDP_INPUT_NEXT_NORMAL,
CDP_INPUT_N_NEXT,
} cdp_next_t;
/*
* Process a frame of cdp packets
* Expect 1 packet / frame
*/
static uword
cdp_node_fn (vlib_main_t * vm,
vlib_node_runtime_t * node, vlib_frame_t * frame)
{
u32 n_left_from, *from;
cdp_input_trace_t *t0;
from = vlib_frame_vector_args (frame); /* array of buffer indices */
n_left_from = frame->n_vectors; /* number of buffer indices */
while (n_left_from > 0)
{
u32 bi0;
vlib_buffer_t *b0;
u32 next0, error0;
bi0 = from[0];
b0 = vlib_get_buffer (vm, bi0);
next0 = CDP_INPUT_NEXT_NORMAL;
/* scan this cdp pkt. error0 is the counter index to bump */
error0 = cdp_input (vm, b0, bi0);
b0->error = node->errors[error0];
/* If this pkt is traced, snapshoot the data */
if (b0->flags & VLIB_BUFFER_IS_TRACED)
{
int len;
t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
len = (b0->current_length < sizeof (t0->data))
? b0->current_length : sizeof (t0->data);
t0->len = len;
clib_memcpy (t0->data, vlib_buffer_get_current (b0), len);
}
/* push this pkt to the next graph node, always error-drop */
vlib_set_next_frame_buffer (vm, node, next0, bi0);
from += 1;
n_left_from -= 1;
}
return frame->n_vectors;
}
/*
* cdp input graph node declaration
*/
VLIB_REGISTER_NODE (cdp_input_node, static) = {
.function = cdp_node_fn,
.name = "cdp-input",
.vector_size = sizeof (u32),
.type = VLIB_NODE_TYPE_INTERNAL,
.n_errors = CDP_N_ERROR,
.error_strings = cdp_error_strings,
.format_trace = cdp_input_format_trace,
.n_next_nodes = CDP_INPUT_N_NEXT,
.next_nodes = {
[CDP_INPUT_NEXT_NORMAL] = "error-drop",
},
};
/*
* cdp periodic function
*/
static uword
cdp_process (vlib_main_t * vm, vlib_node_runtime_t * rt, vlib_frame_t * f)
{
cdp_main_t *cm = &cdp_main;
f64 poll_time_remaining;
uword event_type, *event_data = 0;
/* Start w/ cdp disabled */
poll_time_remaining = 86400.0;
while (1)
{
/* sleep until next poll time, or msg serialize event occurs */
poll_time_remaining =
vlib_process_wait_for_event_or_clock (vm, poll_time_remaining);
event_type = vlib_process_get_events (vm, &event_data);
switch (event_type)
{
case ~0: /* no events => timeout */
break;
case CDP_EVENT_ENABLE:
if (!cm->cdp_protocol_registered)
{
/*
* Dynamically register the cdp input node
* with the snap classifier
*/
snap_register_input_protocol (vm, "cdp-input",
0xC /* ieee_oui, Cisco */ ,
0x2000 /* protocol CDP */ ,
cdp_input_node.index);
snap_register_input_protocol (vm, "cdp-input",
0xC /* ieee_oui, Cisco */ ,
0x2004 /* protocol CDP */ ,
cdp_input_node.index);
#if 0
/*
* Keep this code for reference...
* Register with the hdlc classifier
*/
hdlc_register_input_protocol (vm, HDLC_PROTOCOL_cdp,
cdp_input_node.index);
#endif
/* with ethernet input (for SRP) */
ethernet_register_input_type (vm, ETHERNET_TYPE_CDP /* CDP */ ,
cdp_input_node.index);
cm->cdp_protocol_registered = 1;
}
poll_time_remaining = 10.0;
break;
case CDP_EVENT_DISABLE:
poll_time_remaining = 86400.0;
break;
default:
clib_warning ("BUG: event type 0x%wx", event_type);
break;
}
vec_reset_length (event_data);
/* peer timeout scan, send announcements */
if (vlib_process_suspend_time_is_zero (poll_time_remaining))
{
cdp_periodic (vm);
poll_time_remaining = 10.0;
}
}
return 0;
}
void
vnet_cdp_create_periodic_process (cdp_main_t * cmp)
{
/* Already created the process node? */
if (cmp->cdp_process_node_index > 0)
return;
/* No, create it now and make a note of the node index */
cmp->cdp_process_node_index = vlib_process_create
(cmp->vlib_main, "cdp-process",
cdp_process, 16 /* log2_n_stack_bytes */ );
}
/*
* fd.io coding-style-patch-verification: ON
*
* Local Variables:
* eval: (c-set-style "gnu")
* End:
*/
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