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
|
/*
* OpenVPN -- An application to securely tunnel IP networks
* over a single UDP port, with support for SSL/TLS-based
* session authentication and key exchange,
* packet encryption, packet authentication, and
* packet compression.
*
* Copyright (C) 2002-2017 OpenVPN Technologies, Inc. <sales@openvpn.net>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2
* 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.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#ifndef SHAPER_H
#define SHAPER_H
/*#define SHAPER_DEBUG*/
#ifdef ENABLE_FEATURE_SHAPER
#include "basic.h"
#include "integer.h"
#include "misc.h"
#include "error.h"
#include "interval.h"
/*
* A simple traffic shaper for
* the output direction.
*/
#define SHAPER_MIN 100 /* bytes per second */
#define SHAPER_MAX 100000000
#define SHAPER_MAX_TIMEOUT 10 /* seconds */
#define SHAPER_USE_FP
struct shaper
{
int bytes_per_second;
struct timeval wakeup;
#ifdef SHAPER_USE_FP
double factor;
#else
int factor;
#endif
};
void shaper_msg(struct shaper *s);
void shaper_reset_wakeup(struct shaper *s);
/*
* We want to wake up in delay microseconds. If timeval is larger
* than delay, set timeval to delay.
*/
bool shaper_soonest_event(struct timeval *tv, int delay);
/*
* inline functions
*/
static inline void
shaper_reset(struct shaper *s, int bytes_per_second)
{
s->bytes_per_second = constrain_int(bytes_per_second, SHAPER_MIN, SHAPER_MAX);
#ifdef SHAPER_USE_FP
s->factor = 1000000.0 / (double)s->bytes_per_second;
#else
s->factor = 1000000 / s->bytes_per_second;
#endif
}
static inline void
shaper_init(struct shaper *s, int bytes_per_second)
{
shaper_reset(s, bytes_per_second);
shaper_reset_wakeup(s);
}
static inline int
shaper_current_bandwidth(struct shaper *s)
{
return s->bytes_per_second;
}
/*
* Returns traffic shaping delay in microseconds relative to current
* time, or 0 if no delay.
*/
static inline int
shaper_delay(struct shaper *s)
{
struct timeval tv;
int delay = 0;
if (tv_defined(&s->wakeup))
{
ASSERT(!openvpn_gettimeofday(&tv, NULL));
delay = tv_subtract(&s->wakeup, &tv, SHAPER_MAX_TIMEOUT);
#ifdef SHAPER_DEBUG
dmsg(D_SHAPER_DEBUG, "SHAPER shaper_delay delay=%d", delay);
#endif
}
return delay > 0 ? delay : 0;
}
/*
* We are about to send a datagram of nbytes bytes.
*
* Compute when we can send another datagram,
* based on target throughput (s->bytes_per_second).
*/
static inline void
shaper_wrote_bytes(struct shaper *s, int nbytes)
{
struct timeval tv;
/* compute delay in microseconds */
tv.tv_sec = 0;
#ifdef SHAPER_USE_FP
tv.tv_usec = min_int((int)((double)max_int(nbytes, 100) * s->factor), (SHAPER_MAX_TIMEOUT*1000000));
#else
tv.tv_usec = s->bytes_per_second
? min_int(max_int(nbytes, 100) * s->factor, (SHAPER_MAX_TIMEOUT*1000000))
: 0;
#endif
if (tv.tv_usec)
{
ASSERT(!openvpn_gettimeofday(&s->wakeup, NULL));
tv_add(&s->wakeup, &tv);
#ifdef SHAPER_DEBUG
dmsg(D_SHAPER_DEBUG, "SHAPER shaper_wrote_bytes bytes=%d delay=%d sec=%d usec=%d",
nbytes,
(int)tv.tv_usec,
(int)s->wakeup.tv_sec,
(int)s->wakeup.tv_usec);
#endif
}
}
#if 0
/*
* Increase/Decrease bandwidth by a percentage.
*
* Return true if bandwidth changed.
*/
static inline bool
shaper_change_pct(struct shaper *s, int pct)
{
const int orig_bandwidth = s->bytes_per_second;
const int new_bandwidth = orig_bandwidth + (orig_bandwidth * pct / 100);
ASSERT(s->bytes_per_second);
shaper_reset(s, new_bandwidth);
return s->bytes_per_second != orig_bandwidth;
}
#endif
#endif /* ENABLE_FEATURE_SHAPER */
#endif /* ifndef SHAPER_H */
|
