aboutsummaryrefslogtreecommitdiffstats
path: root/src/vnet/adj/adj_l2.c
blob: 8a2126b2d7facb648c46443035430887b1797e55 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
/*
 * Copyright (c) 2016 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 <vnet/vnet.h>
#include <vnet/adj/adj_l2.h>
#include <vnet/ethernet/ethernet.h>
#include <vnet/ip/ip.h>

/**
 * @brief Trace data for a L2 Midchain
 */
typedef struct adj_l2_trace_t_ {
    /** Adjacency index taken. */
    u32 adj_index;
} adj_l2_trace_t;

static u8 *
format_adj_l2_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 *);
    adj_l2_trace_t * t = va_arg (*args, adj_l2_trace_t *);

    s = format (s, "adj-idx %d : %U",
		t->adj_index,
		format_ip_adjacency, t->adj_index, FORMAT_IP_ADJACENCY_NONE);
    return s;
}

typedef enum adj_l2_rewrite_next_t_
{
    ADJ_L2_REWRITE_NEXT_DROP,
} adj_l2_rewrite_next_t;

always_inline uword
adj_l2_rewrite_inline (vlib_main_t * vm,
		       vlib_node_runtime_t * node,
		       vlib_frame_t * frame,
		       int is_midchain)
{
    u32 * from = vlib_frame_vector_args (frame);
    u32 n_left_from, n_left_to_next, * to_next, next_index;
    u32 thread_index = vlib_get_thread_index();
    ethernet_main_t * em = &ethernet_main;

    n_left_from = frame->n_vectors;
    next_index = node->cached_next_index;

    while (n_left_from > 0)
    {
	vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);

	while (n_left_from > 0 && n_left_to_next > 0)
	{
	    ip_adjacency_t * adj0;
	    vlib_buffer_t * p0;
	    char *h0;
	    u32 pi0, rw_len0, adj_index0, next0 = 0;
	    u32 tx_sw_if_index0;

	    pi0 = to_next[0] = from[0];
	    from += 1;
	    n_left_from -= 1;
	    to_next += 1;
	    n_left_to_next -= 1;

	    p0 = vlib_get_buffer (vm, pi0);
	    h0 = vlib_buffer_get_current (p0);

	    adj_index0 = vnet_buffer (p0)->ip.adj_index[VLIB_TX];

	    adj0 = adj_get (adj_index0);

	    /* Guess we are only writing on simple Ethernet header. */
	    vnet_rewrite_one_header (adj0[0], h0,
				     sizeof (ethernet_header_t));

	    /* Update packet buffer attributes/set output interface. */
	    rw_len0 = adj0[0].rewrite_header.data_bytes;
	    vnet_buffer(p0)->ip.save_rewrite_length = rw_len0;
            vnet_buffer(p0)->sw_if_index[VLIB_TX] = adj0->rewrite_header.sw_if_index;
            /* since we are coming out of the L2 world, where the vlib_buffer
             * union is used for other things, make sure it is clean for
             * MPLS from now on.
             */
            vnet_buffer(p0)->mpls.first = 0;

	    vlib_increment_combined_counter(&adjacency_counters,
                                            thread_index,
                                            adj_index0,
                                            /* packet increment */ 0,
                                            /* byte increment */ rw_len0);

	    /* Check MTU of outgoing interface. */
	    if (PREDICT_TRUE((vlib_buffer_length_in_chain (vm, p0)  <=
			      adj0[0].rewrite_header.max_l3_packet_bytes)))
	    {
		/* Don't adjust the buffer for ttl issue; icmp-error node wants
		 * to see the IP headerr */
		p0->current_data -= rw_len0;
		p0->current_length += rw_len0;
		tx_sw_if_index0 = adj0[0].rewrite_header.sw_if_index;

		if (is_midchain)
		{
		    adj0->sub_type.midchain.fixup_func(
                        vm, adj0, p0,
                        adj0->sub_type.midchain.fixup_data);
		}

		vnet_buffer (p0)->sw_if_index[VLIB_TX] = tx_sw_if_index0;

		/*
		 * Follow the feature ARC. this will result eventually in
		 * the midchain-tx node
		 */
		vnet_feature_arc_start(em->output_feature_arc_index, tx_sw_if_index0, &next0, p0);
	    }
	    else
	    {
		/* can't fragment L2 */
		next0 = ADJ_L2_REWRITE_NEXT_DROP;
	    }

	    if (PREDICT_FALSE(p0->flags & VLIB_BUFFER_IS_TRACED))
	    {
		adj_l2_trace_t *tr = vlib_add_trace (vm, node,
						     p0, sizeof (*tr));
		tr->adj_index = vnet_buffer(p0)->ip.adj_index[VLIB_TX];
	    }

	    vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
					     to_next, n_left_to_next,
					     pi0, next0);
	}

	vlib_put_next_frame (vm, node, next_index, n_left_to_next);
    }

    return frame->n_vectors;
}

VLIB_NODE_FN (adj_l2_rewrite_node) (vlib_main_t * vm,
		vlib_node_runtime_t * node,
		vlib_frame_t * frame)
{
    return adj_l2_rewrite_inline (vm, node, frame, 0);
}

VLIB_NODE_FN (adj_l2_midchain_node) (vlib_main_t * vm,
		 vlib_node_runtime_t * node,
		 vlib_frame_t * frame)
{
    return adj_l2_rewrite_inline (vm, node, frame, 1);
}

VLIB_REGISTER_NODE (adj_l2_rewrite_node) = {
    .name = "adj-l2-rewrite",
    .vector_size = sizeof (u32),

    .format_trace = format_adj_l2_trace,

    .n_next_nodes = 1,
    .next_nodes = {
	[ADJ_L2_REWRITE_NEXT_DROP] = "error-drop",
    },
};

VLIB_REGISTER_NODE (adj_l2_midchain_node) = {
    .name = "adj-l2-midchain",
    .vector_size = sizeof (u32),

    .format_trace = format_adj_l2_trace,

    .n_next_nodes = 1,
    .next_nodes = {
	[ADJ_L2_REWRITE_NEXT_DROP] = "error-drop",
    },
};