1/*
2 * Copyright (c) 2010-2014 Apple Inc. All rights reserved.
3 *
4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5 *
6 * This file contains Original Code and/or Modifications of Original Code
7 * as defined in and that are subject to the Apple Public Source License
8 * Version 2.0 (the 'License'). You may not use this file except in
9 * compliance with the License. The rights granted to you under the License
10 * may not be used to create, or enable the creation or redistribution of,
11 * unlawful or unlicensed copies of an Apple operating system, or to
12 * circumvent, violate, or enable the circumvention or violation of, any
13 * terms of an Apple operating system software license agreement.
14 *
15 * Please obtain a copy of the License at
16 * http://www.opensource.apple.com/apsl/ and read it before using this file.
17 *
18 * The Original Code and all software distributed under the License are
19 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23 * Please see the License for the specific language governing rights and
24 * limitations under the License.
25 *
26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27 */
28/*-
29 * Copyright (c) 2008 Swinburne University of Technology, Melbourne, Australia
30 * All rights reserved.
31 *
32 * This software was developed at the Centre for Advanced Internet
33 * Architectures, Swinburne University, by Lawrence Stewart and James Healy,
34 * made possible in part by a grant from the Cisco University Research Program
35 * Fund at Community Foundation Silicon Valley.
36 *
37 * Redistribution and use in source and binary forms, with or without
38 * modification, are permitted provided that the following conditions
39 * are met:
40 * 1. Redistributions of source code must retain the above copyright
41 *    notice, this list of conditions and the following disclaimer.
42 * 2. Redistributions in binary form must reproduce the above copyright
43 *    notice, this list of conditions and the following disclaimer in the
44 *    documentation and/or other materials provided with the distribution.
45 *
46 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
47 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
48 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
49 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
50 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
51 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
52 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
53 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
54 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
55 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
56 * SUCH DAMAGE.
57 *
58 * $FreeBSD$
59 */
60
61#ifndef _NETINET_CC_H_
62#define _NETINET_CC_H_
63
64#ifdef KERNEL
65#include <netinet/tcp.h>
66#include <netinet/tcp_var.h>
67#include <kern/zalloc.h>
68
69#define	TCP_CC_ALGO_NONE		0
70#define	TCP_CC_ALGO_NEWRENO_INDEX	1
71#define	TCP_CC_ALGO_BACKGROUND_INDEX	2 /* CC for background transport */
72#define	TCP_CC_ALGO_CUBIC_INDEX		3 /* default CC algorithm */
73#define	TCP_CC_ALGO_COUNT		4 /* Count of CC algorithms */
74
75#define TCP_CA_NAME_MAX 16		/* Maximum characters in the name of a CC algorithm */
76
77/*
78 * Structure to hold definition various actions defined by a congestion
79 * control algorithm for TCP. This can be used to change the congestion
80 * control on a connection based on the user settings of priority of a
81 * connection.
82 */
83struct tcp_cc_algo {
84	char name[TCP_CA_NAME_MAX];
85	uint32_t num_sockets;
86	uint32_t flags;
87
88	/* init the congestion algorithm for the specified control block */
89	int (*init) (struct tcpcb *tp);
90
91	/*
92	 * cleanup any state that is stored in the connection
93	 * related to the algorithm
94	 */
95	int (*cleanup) (struct tcpcb *tp);
96
97	/* initialize cwnd at the start of a connection */
98	void (*cwnd_init) (struct tcpcb *tp);
99
100	/*
101	 * called on the receipt of in-sequence ack during congestion
102	 * avoidance phase
103	 */
104	void (*congestion_avd) (struct tcpcb *tp, struct tcphdr *th);
105
106	/* called on the receipt of a valid ack */
107	void (*ack_rcvd) (struct tcpcb *tp, struct tcphdr *th);
108
109	/* called before entering FR */
110	void (*pre_fr) (struct tcpcb *tp);
111
112	/*  after exiting FR */
113	void (*post_fr) (struct tcpcb *tp, struct tcphdr *th);
114
115	/* perform tasks when data transfer resumes after an idle period */
116	void (*after_idle) (struct tcpcb *tp);
117
118	/* perform tasks when the connection's retransmit timer expires */
119	void (*after_timeout) (struct tcpcb *tp);
120
121	/* Whether or not to delay the ack */
122	int (*delay_ack)(struct tcpcb *tp, struct tcphdr *th);
123
124	/* Switch a connection to this CC algorithm after sending some packets */
125	void (*switch_to)(struct tcpcb *tp, uint16_t old_cc_index);
126
127} __attribute__((aligned(4)));
128
129extern struct zone *tcp_cc_zone;
130
131extern struct tcp_cc_algo* tcp_cc_algo_list[TCP_CC_ALGO_COUNT];
132
133#define CC_ALGO(tp) (tcp_cc_algo_list[tp->tcp_cc_index])
134#define	TCP_CC_CWND_INIT_BYTES	4380
135
136extern void	tcp_cc_init(void);
137extern void tcp_cc_resize_sndbuf(struct tcpcb *tp);
138extern void tcp_bad_rexmt_fix_sndbuf(struct tcpcb *tp);
139extern void tcp_cc_cwnd_init_or_reset(struct tcpcb *tp);
140extern int tcp_cc_delay_ack(struct tcpcb *tp, struct tcphdr *th);
141extern void tcp_ccdbg_trace(struct tcpcb *tp, struct tcphdr *th,
142	int32_t event);
143extern void tcp_cc_allocate_state(struct tcpcb *tp);
144extern void tcp_cc_after_idle_stretchack(struct tcpcb *tp);
145
146#endif /* KERNEL */
147#endif /* _NETINET_CC_H_ */
148