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
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
|
/* SPDX-License-Identifier: Apache-2.0
* Copyright(c) 2021 Cisco Systems, Inc.
*/
#include <vlib/vlib.h>
#include <vnet/feature/feature.h>
#include <snort/snort.h>
typedef struct
{
u32 next_index;
u32 sw_if_index;
u16 instance;
u16 qpair;
u32 enq_slot;
u32 desc_index;
daq_vpp_desc_t desc;
} snort_enq_trace_t;
static u8 *
format_snort_enq_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 *);
snort_enq_trace_t *t = va_arg (*args, snort_enq_trace_t *);
u32 indent = format_get_indent (s);
s = format (s,
"sw-if-index %u next-index %u\n"
"%Uinstance %u qpair %u desc-index %u slot %u\n"
"%Udesc: buffer-pool %u offset %u len %u address-space-id %u\n",
t->sw_if_index, t->next_index, format_white_space, indent,
t->instance, t->qpair, t->desc_index, t->enq_slot,
format_white_space, indent, t->desc.buffer_pool, t->desc.offset,
t->desc.length, t->desc.address_space_id);
return s;
}
#define foreach_snort_enq_error \
_ (SOCKET_ERROR, "write socket error") \
_ (NO_INSTANCE, "no snort instance") \
_ (NO_ENQ_SLOTS, "no enqueue slots (packet dropped)")
typedef enum
{
#define _(sym, str) SNORT_ENQ_ERROR_##sym,
foreach_snort_enq_error
#undef _
SNORT_ENQ_N_ERROR,
} snort_enq_error_t;
static char *snort_enq_error_strings[] = {
#define _(sym, string) string,
foreach_snort_enq_error
#undef _
};
static_always_inline uword
snort_enq_node_inline (vlib_main_t *vm, vlib_node_runtime_t *node,
vlib_frame_t *frame, int with_trace)
{
snort_main_t *sm = &snort_main;
snort_instance_t *si = 0;
snort_qpair_t *qp = 0;
u32 thread_index = vm->thread_index;
u32 n_left = frame->n_vectors;
u32 n_trace = 0;
u32 total_enq = 0, n_processed = 0;
u32 *from = vlib_frame_vector_args (frame);
vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b = bufs;
u16 nexts[VLIB_FRAME_SIZE], *next = nexts;
vlib_get_buffers (vm, from, bufs, n_left);
while (n_left)
{
u64 fa_data;
u32 instance_index, next_index, n;
u32 l3_offset;
fa_data =
*(u64 *) vnet_feature_next_with_data (&next_index, b[0], sizeof (u64));
instance_index = (u32) (fa_data & 0xffffffff);
l3_offset =
(fa_data >> 32) ? vnet_buffer (b[0])->ip.save_rewrite_length : 0;
si = vec_elt_at_index (sm->instances, instance_index);
/* if client isn't connected skip enqueue and take default action */
if (PREDICT_FALSE (si->client_index == ~0))
{
if (si->drop_on_disconnect)
next[0] = SNORT_ENQ_NEXT_DROP;
else
next[0] = next_index;
next++;
n_processed++;
}
else
{
qp = vec_elt_at_index (si->qpairs, thread_index);
n = qp->n_pending++;
daq_vpp_desc_t *d = qp->pending_descs + n;
qp->pending_nexts[n] = next_index;
qp->pending_buffers[n] = from[0];
vlib_buffer_chain_linearize (vm, b[0]);
/* If this pkt is traced, snapshoot the data */
if (with_trace && b[0]->flags & VLIB_BUFFER_IS_TRACED)
n_trace++;
/* fill descriptor */
d->buffer_pool = b[0]->buffer_pool_index;
d->length = b[0]->current_length;
d->offset = (u8 *) b[0]->data + b[0]->current_data + l3_offset -
sm->buffer_pool_base_addrs[d->buffer_pool];
d->address_space_id = vnet_buffer (b[0])->sw_if_index[VLIB_RX];
}
n_left--;
from++;
b++;
}
if (n_processed)
{
vlib_node_increment_counter (vm, snort_enq_node.index,
SNORT_ENQ_ERROR_NO_INSTANCE, n_processed);
vlib_buffer_enqueue_to_next (vm, node, vlib_frame_vector_args (frame),
nexts, n_processed);
}
pool_foreach (si, sm->instances)
{
u32 head, freelist_len, n_pending, n_enq, mask;
u64 ctr = 1;
qp = vec_elt_at_index (si->qpairs, thread_index);
mask = pow2_mask (qp->log2_queue_size);
n_pending = qp->n_pending;
qp->n_pending = 0;
if (n_pending == 0)
continue;
freelist_len = vec_len (qp->freelist);
if (freelist_len < n_pending)
{
n_enq = freelist_len;
vlib_buffer_free (vm, qp->pending_buffers + n_enq,
n_pending - n_enq);
vlib_node_increment_counter (vm, snort_enq_node.index,
SNORT_ENQ_ERROR_NO_ENQ_SLOTS,
n_pending - n_enq);
}
else
n_enq = n_pending;
if (n_enq == 0)
continue;
total_enq += n_enq;
head = *qp->enq_head;
for (u32 i = 0; i < n_enq; i++)
{
u32 desc_index = qp->freelist[--freelist_len];
qp->next_indices[desc_index] = qp->pending_nexts[i];
ASSERT (qp->buffer_indices[desc_index] == ~0);
qp->buffer_indices[desc_index] = qp->pending_buffers[i];
clib_memcpy_fast (qp->descriptors + desc_index,
qp->pending_descs + i, sizeof (daq_vpp_desc_t));
qp->enq_ring[head & mask] = desc_index;
/* trace */
if (with_trace && n_trace)
{
vlib_buffer_t *tb = vlib_get_buffer (vm, qp->pending_buffers[i]);
if (tb->flags & VLIB_BUFFER_IS_TRACED)
{
snort_enq_trace_t *t =
vlib_add_trace (vm, node, tb, sizeof (*t));
t->sw_if_index = vnet_buffer (tb)->sw_if_index[VLIB_RX];
t->next_index = qp->pending_nexts[i];
t->instance = si->index;
t->qpair = qp - si->qpairs;
t->enq_slot = head & mask;
t->desc_index = desc_index;
clib_memcpy_fast (&t->desc, qp->pending_descs + i,
sizeof (daq_vpp_desc_t));
}
}
head = head + 1;
}
__atomic_store_n (qp->enq_head, head, __ATOMIC_RELEASE);
vec_set_len (qp->freelist, freelist_len);
if (sm->input_mode == VLIB_NODE_STATE_INTERRUPT)
{
if (write (qp->enq_fd, &ctr, sizeof (ctr)) < 0)
vlib_node_increment_counter (vm, snort_enq_node.index,
SNORT_ENQ_ERROR_SOCKET_ERROR, 1);
}
}
return total_enq;
}
VLIB_NODE_FN (snort_enq_node)
(vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *frame)
{
if (PREDICT_FALSE (node->flags & VLIB_NODE_FLAG_TRACE))
return snort_enq_node_inline (vm, node, frame, 1 /* is_trace*/);
else
return snort_enq_node_inline (vm, node, frame, 0 /* is_trace*/);
}
VLIB_REGISTER_NODE (snort_enq_node) = {
.name = "snort-enq",
.vector_size = sizeof (u32),
.format_trace = format_snort_enq_trace,
.type = VLIB_NODE_TYPE_INTERNAL,
.n_next_nodes = SNORT_ENQ_N_NEXT_NODES,
.next_nodes = SNORT_ENQ_NEXT_NODES,
.n_errors = ARRAY_LEN (snort_enq_error_strings),
.error_strings = snort_enq_error_strings,
};
|
