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
|
/*
* netsniff-ng - the packet sniffing beast
* Copyright 2009, 2010 Daniel Borkmann.
* Subject to the GPL, version 2.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/mman.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <linux/if_ether.h>
#include "xmalloc.h"
#include "die.h"
#include "ring_rx.h"
#include "built_in.h"
void destroy_rx_ring(int sock, struct ring *ring)
{
int ret;
munmap(ring->mm_space, ring->mm_len);
ring->mm_len = 0;
fmemset(&ring->layout, 0, sizeof(ring->layout));
ret = setsockopt(sock, SOL_PACKET, PACKET_RX_RING, &ring->layout,
sizeof(ring->layout));
if (unlikely(ret))
panic("Cannot destroy the RX_RING: %s!\n", strerror(errno));
xfree(ring->frames);
}
void setup_rx_ring_layout(int sock, struct ring *ring, unsigned int size,
int jumbo_support, bool v3)
{
fmemset(&ring->layout, 0, sizeof(ring->layout));
ring->layout.tp_block_size = (jumbo_support ?
getpagesize() << 4 :
getpagesize() << 2);
ring->layout.tp_frame_size = (jumbo_support ?
TPACKET_ALIGNMENT << 12 :
TPACKET_ALIGNMENT << 7);
ring->layout.tp_block_nr = size / ring->layout.tp_block_size;
ring->layout.tp_frame_nr = ring->layout.tp_block_size /
ring->layout.tp_frame_size *
ring->layout.tp_block_nr;
if (v3) {
/* Pass out, if this will ever change and we do crap on it! */
build_bug_on(offsetof(struct tpacket_req, tp_frame_nr) !=
offsetof(struct tpacket_req3, tp_frame_nr) &&
sizeof(struct tpacket_req) !=
offsetof(struct tpacket_req3, tp_retire_blk_tov));
set_sockopt_tpacket_v3(sock);
} else {
set_sockopt_tpacket_v2(sock);
}
ring_verify_layout(ring);
}
void create_rx_ring(int sock, struct ring *ring, int verbose)
{
int ret;
retry:
ret = setsockopt(sock, SOL_PACKET, PACKET_RX_RING, &ring->layout,
sizeof(ring->layout));
if (errno == ENOMEM && ring->layout.tp_block_nr > 1) {
ring->layout.tp_block_nr >>= 1;
ring->layout.tp_frame_nr = ring->layout.tp_block_size /
ring->layout.tp_frame_size *
ring->layout.tp_block_nr;
goto retry;
}
if (ret < 0)
panic("Cannot allocate RX_RING!\n");
ring->mm_len = ring->layout.tp_block_size * ring->layout.tp_block_nr;
if (verbose) {
printf("RX: %.2Lf MiB, %u Frames, each %u Byte allocated\n",
(long double) ring->mm_len / (1 << 20),
ring->layout.tp_frame_nr, ring->layout.tp_frame_size);
}
}
void mmap_rx_ring(int sock, struct ring *ring)
{
ring->mm_space = mmap(0, ring->mm_len, PROT_READ | PROT_WRITE,
MAP_SHARED | MAP_LOCKED | MAP_POPULATE, sock, 0);
if (ring->mm_space == MAP_FAILED) {
destroy_rx_ring(sock, ring);
panic("Cannot mmap RX_RING!\n");
}
}
void alloc_rx_ring_frames(struct ring *ring)
{
int i;
size_t len = ring->layout.tp_frame_nr * sizeof(*ring->frames);
ring->frames = xmalloc_aligned(len, CO_CACHE_LINE_SIZE);
fmemset(ring->frames, 0, len);
for (i = 0; i < ring->layout.tp_frame_nr; ++i) {
ring->frames[i].iov_len = ring->layout.tp_frame_size;
ring->frames[i].iov_base = ring->mm_space +
(i * ring->layout.tp_frame_size);
}
}
void bind_rx_ring(int sock, struct ring *ring, int ifindex)
{
int ret;
/*
* The RX_RING registers itself to the networking stack with
* dev_add_pack(), so we have one single RX_RING for all devs
* otherwise you'll get the packet twice.
*/
fmemset(&ring->s_ll, 0, sizeof(ring->s_ll));
ring->s_ll.sll_family = AF_PACKET;
ring->s_ll.sll_protocol = htons(ETH_P_ALL);
ring->s_ll.sll_ifindex = ifindex;
ring->s_ll.sll_hatype = 0;
ring->s_ll.sll_halen = 0;
ring->s_ll.sll_pkttype = 0;
ret = bind(sock, (struct sockaddr *) &ring->s_ll, sizeof(ring->s_ll));
if (ret < 0) {
destroy_rx_ring(sock, ring);
panic("Cannot bind RX_RING!\n");
}
}
|
