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
|
/* PTP classifier
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of version 2 of the GNU General Public
* License as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*/
/* The below program is the bpf_asm (tools/net/) representation of
* the opcode array in the ptp_filter structure.
*
* For convenience, this can easily be altered and reviewed with
* bpf_asm and bpf_dbg, e.g. `./bpf_asm -c prog` where prog is a
* simple file containing the below program:
*
* ldh [12] ; load ethertype
*
* ; PTP over UDP over IPv4 over Ethernet
* test_ipv4:
* jneq #0x800, test_ipv6 ; ETH_P_IP ?
* ldb [23] ; load proto
* jneq #17, drop_ipv4 ; IPPROTO_UDP ?
* ldh [20] ; load frag offset field
* jset #0x1fff, drop_ipv4 ; don't allow fragments
* ldxb 4*([14]&0xf) ; load IP header len
* ldh [x + 16] ; load UDP dst port
* jneq #319, drop_ipv4 ; is port PTP_EV_PORT ?
* ldh [x + 22] ; load payload
* and #0xf ; mask PTP_CLASS_VMASK
* or #0x10 ; PTP_CLASS_IPV4
* ret a ; return PTP class
* drop_ipv4: ret #0x0 ; PTP_CLASS_NONE
*
* ; PTP over UDP over IPv6 over Ethernet
* test_ipv6:
* jneq #0x86dd, test_8021q ; ETH_P_IPV6 ?
* ldb [20] ; load proto
* jneq #17, drop_ipv6 ; IPPROTO_UDP ?
* ldh [56] ; load UDP dst port
* jneq #319, drop_ipv6 ; is port PTP_EV_PORT ?
* ldh [62] ; load payload
* and #0xf ; mask PTP_CLASS_VMASK
* or #0x20 ; PTP_CLASS_IPV6
* ret a ; return PTP class
* drop_ipv6: ret #0x0 ; PTP_CLASS_NONE
*
* ; PTP over 802.1Q over Ethernet
* test_8021q:
* jneq #0x8100, test_ieee1588 ; ETH_P_8021Q ?
* ldh [16] ; load inner type
* jneq #0x88f7, drop_ieee1588 ; ETH_P_1588 ?
* ldb [18] ; load payload
* and #0x8 ; as we don't have ports here, test
* jneq #0x0, drop_ieee1588 ; for PTP_GEN_BIT and drop these
* ldh [18] ; reload payload
* and #0xf ; mask PTP_CLASS_VMASK
* or #0x40 ; PTP_CLASS_V2_VLAN
* ret a ; return PTP class
*
* ; PTP over Ethernet
* test_ieee1588:
* jneq #0x88f7, drop_ieee1588 ; ETH_P_1588 ?
* ldb [14] ; load payload
* and #0x8 ; as we don't have ports here, test
* jneq #0x0, drop_ieee1588 ; for PTP_GEN_BIT and drop these
* ldh [14] ; reload payload
* and #0xf ; mask PTP_CLASS_VMASK
* or #0x30 ; PTP_CLASS_L2
* ret a ; return PTP class
* drop_ieee1588: ret #0x0 ; PTP_CLASS_NONE
*/
#include <linux/skbuff.h>
#include <linux/filter.h>
#include <linux/ptp_classify.h>
static struct sk_filter *ptp_insns __read_mostly;
unsigned int ptp_classify_raw(const struct sk_buff *skb)
{
return SK_RUN_FILTER(ptp_insns, skb);
}
EXPORT_SYMBOL_GPL(ptp_classify_raw);
void __init ptp_classifier_init(void)
{
static struct sock_filter ptp_filter[] = {
{ 0x28, 0, 0, 0x0000000c },
{ 0x15, 0, 12, 0x00000800 },
{ 0x30, 0, 0, 0x00000017 },
{ 0x15, 0, 9, 0x00000011 },
{ 0x28, 0, 0, 0x00000014 },
{ 0x45, 7, 0, 0x00001fff },
{ 0xb1, 0, 0, 0x0000000e },
{ 0x48, 0, 0, 0x00000010 },
{ 0x15, 0, 4, 0x0000013f },
{ 0x48, 0, 0, 0x00000016 },
{ 0x54, 0, 0, 0x0000000f },
{ 0x44, 0, 0, 0x00000010 },
{ 0x16, 0, 0, 0x00000000 },
{ 0x06, 0, 0, 0x00000000 },
{ 0x15, 0, 9, 0x000086dd },
{ 0x30, 0, 0, 0x00000014 },
{ 0x15, 0, 6, 0x00000011 },
{ 0x28, 0, 0, 0x00000038 },
{ 0x15, 0, 4, 0x0000013f },
{ 0x28, 0, 0, 0x0000003e },
{ 0x54, 0, 0, 0x0000000f },
{ 0x44, 0, 0, 0x00000020 },
{ 0x16, 0, 0, 0x00000000 },
{ 0x06, 0, 0, 0x00000000 },
{ 0x15, 0, 9, 0x00008100 },
{ 0x28, 0, 0, 0x00000010 },
{ 0x15, 0, 15, 0x000088f7 },
{ 0x30, 0, 0, 0x00000012 },
{ 0x54, 0, 0, 0x00000008 },
{ 0x15, 0, 12, 0x00000000 },
{ 0x28, 0, 0, 0x00000012 },
{ 0x54, 0, 0, 0x0000000f },
{ 0x44, 0, 0, 0x00000040 },
{ 0x16, 0, 0, 0x00000000 },
{ 0x15, 0, 7, 0x000088f7 },
{ 0x30, 0, 0, 0x0000000e },
{ 0x54, 0, 0, 0x00000008 },
{ 0x15, 0, 4, 0x00000000 },
{ 0x28, 0, 0, 0x0000000e },
{ 0x54, 0, 0, 0x0000000f },
{ 0x44, 0, 0, 0x00000030 },
{ 0x16, 0, 0, 0x00000000 },
{ 0x06, 0, 0, 0x00000000 },
};
struct sock_fprog ptp_prog = {
.len = ARRAY_SIZE(ptp_filter), .filter = ptp_filter,
};
BUG_ON(sk_unattached_filter_create(&ptp_insns, &ptp_prog));
}
|
