1/*
2 * Copyright (c) 2010-2011 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
66#include <netinet/tcp_var.h>
67
68#define TCP_CC_ALGO_NEWRENO_INDEX 0	/* default congestion control algorithm */
69#define TCP_CC_ALGO_BACKGROUND_INDEX 1	/* congestion control for background transport */
70#define TCP_CC_ALGO_COUNT 2		/* Count of CC algorithms defined */
71
72#define TCP_CA_NAME_MAX 16		/* Maximum characters in the name of a CC algorithm */
73
74/*
75 * Structure to hold definition various actions defined by a congestion control
76 * algorithm for TCP. This can be used to change the congestion control on a
77 * connection based on the user settings of priority of a connection.
78 */
79struct tcp_cc_algo {
80	char name[TCP_CA_NAME_MAX];
81	uint32_t num_sockets;
82	uint32_t flags;
83
84	/* init the congestion algorithm for the specified control block */
85	int (*init) (struct tcpcb *tp);
86
87	/* cleanup any state that is stored in the connection related to the algorithm */
88	int (*cleanup) (struct tcpcb *tp);
89
90	/* initialize cwnd at the start of a connection */
91	void (*cwnd_init) (struct tcpcb *tp);
92
93	/* called on the receipt of in-sequence ack during congestion avoidance phase */
94	void (*inseq_ack_rcvd) (struct tcpcb *tp, struct tcphdr *th);
95
96	/* called on the receipt of a valid ack */
97	void (*ack_rcvd) (struct tcpcb *tp, struct tcphdr *th);
98
99	/* called before entering FR */
100	void (*pre_fr) (struct tcpcb *tp);
101
102	/*  after exiting FR */
103	void (*post_fr) (struct tcpcb *tp, struct tcphdr *th);
104
105	/* perform tasks when data transfer resumes after an idle period */
106	void (*after_idle) (struct tcpcb *tp);
107
108	/* perform tasks when the connection's retransmit timer expires */
109	void (*after_timeout) (struct tcpcb *tp);
110
111	/* Whether or not to delay the ack */
112	int (*delay_ack)(struct tcpcb *tp, struct tcphdr *th);
113
114	/* Switch a connection to this CC algorithm after sending some packets */
115	void (*switch_to)(struct tcpcb *tp, uint16_t old_cc_index);
116
117} __attribute__((aligned(4)));
118
119extern struct tcp_cc_algo* tcp_cc_algo_list[TCP_CC_ALGO_COUNT];
120
121#define CC_ALGO(tp) (tcp_cc_algo_list[tp->tcp_cc_index])
122
123extern void tcp_cc_resize_sndbuf(struct tcpcb *tp);
124extern void tcp_bad_rexmt_fix_sndbuf(struct tcpcb *tp);
125
126#endif /* KERNEL */
127#endif /* _NETINET_CC_H_ */
128