1 /*
2 * Copyright (c) 2010-2021 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 PRIVATE
65
66 #include <netinet/in.h>
67
68 /*
69 * Data structure to collect and display congestion control debug information
70 */
71 struct tcp_cc_debug_state {
72 u_int64_t ccd_tsns;
73 char ccd_srcaddr[INET6_ADDRSTRLEN];
74 uint16_t ccd_srcport;
75 char ccd_destaddr[INET6_ADDRSTRLEN];
76 uint16_t ccd_destport;
77 uint32_t ccd_snd_cwnd;
78 uint32_t ccd_snd_wnd;
79 uint32_t ccd_snd_ssthresh;
80 uint32_t ccd_pipeack;
81 uint32_t ccd_rttcur;
82 uint32_t ccd_rxtcur;
83 uint32_t ccd_srtt;
84 uint32_t ccd_event;
85 uint32_t ccd_sndcc;
86 uint32_t ccd_sndhiwat;
87 uint32_t ccd_bytes_acked;
88 u_int8_t ccd_cc_index;
89 u_int8_t ccd_unused_1__;
90 u_int16_t ccd_unused_2__;
91 union {
92 struct {
93 uint32_t ccd_last_max;
94 uint32_t ccd_tcp_win;
95 uint32_t ccd_target_win;
96 uint32_t ccd_avg_lastmax;
97 uint32_t ccd_mean_deviation;
98 } cubic_state;
99 struct {
100 u_int32_t led_base_rtt;
101 } ledbat_state;
102 } u;
103 };
104
105 /*
106 * Values of ccd_cc_index
107 */
108 #define TCP_CC_ALGO_NONE 0
109 #define TCP_CC_ALGO_NEWRENO_INDEX 1
110 #define TCP_CC_ALGO_BACKGROUND_INDEX 2 /* CC for background transport */
111 #define TCP_CC_ALGO_CUBIC_INDEX 3 /* default CC algorithm */
112 #define TCP_CC_ALGO_PRAGUE_INDEX 4 /* L4S CC algorithm */
113 #define TCP_CC_ALGO_COUNT 5 /* Count of CC algorithms */
114
115 /*
116 * Values of ccd_event
117 */
118 #define TCP_CC_EVENT_LIST \
119 X(TCP_CC_CWND_INIT) \
120 X(TCP_CC_INSEQ_ACK_RCVD) \
121 X(TCP_CC_ACK_RCVD) \
122 X(TCP_CC_ENTER_FASTRECOVERY) \
123 X(TCP_CC_IN_FASTRECOVERY) \
124 X(TCP_CC_EXIT_FASTRECOVERY) \
125 X(TCP_CC_PARTIAL_ACK) \
126 X(TCP_CC_IDLE_TIMEOUT) \
127 X(TCP_CC_REXMT_TIMEOUT) \
128 X(TCP_CC_ECN_RCVD) \
129 X(TCP_CC_BAD_REXMT_RECOVERY) \
130 X(TCP_CC_OUTPUT_ERROR) \
131 X(TCP_CC_CHANGE_ALGO) \
132 X(TCP_CC_FLOW_CONTROL) \
133 X(TCP_CC_SUSPEND) \
134 X(TCP_CC_LIMITED_TRANSMIT) \
135 X(TCP_CC_EARLY_RETRANSMIT) \
136 X(TCP_CC_TLP_RECOVERY) \
137 X(TCP_CC_TLP_RECOVER_LASTPACKET) \
138 X(TCP_CC_DELAY_FASTRECOVERY) \
139 X(TCP_CC_TLP_IN_FASTRECOVERY) \
140 X(TCP_CC_DSACK_BAD_REXMT) \
141 X(TCP_CC_FIRST_REXMT) \
142 X(TCP_CC_FLOW_CONGESTION_NOTIFIED) \
143 X(MAX_TCP_CC_EVENTS)
144
145 enum tcp_cc_event {
146 #define X(name, ...) name,
147 TCP_CC_EVENT_LIST
148 #undef X
149 };
150
151 /*
152 * Kernel control ID
153 */
154 #define TCP_CC_CONTROL_NAME "com.apple.network.tcp_ccdebug"
155
156 #endif /* PRIVATE */
157
158 #ifdef KERNEL_PRIVATE
159
160 #include <netinet/tcp.h>
161 #include <netinet/tcp_var.h>
162 #include <kern/zalloc.h>
163
164 /*
165 * Maximum characters in the name of a CC algorithm
166 */
167 #define TCP_CA_NAME_MAX 16
168
169 extern int tcp_recv_bg;
170 extern uint32_t bg_ss_fltsz;
171
172 /*
173 * Structure to hold definition various actions defined by a congestion
174 * control algorithm for TCP. This can be used to change the congestion
175 * control on a connection based on the user settings of priority of a
176 * connection.
177 */
178 struct tcp_cc_algo {
179 char name[TCP_CA_NAME_MAX];
180 _Atomic uint32_t num_sockets;
181 uint32_t flags;
182
183 /* init the congestion algorithm for the specified control block */
184 int (*init) (struct tcpcb *tp);
185
186 /*
187 * cleanup any state that is stored in the connection
188 * related to the algorithm
189 */
190 int (*cleanup) (struct tcpcb *tp);
191
192 /* initialize cwnd at the start of a connection */
193 void (*cwnd_init) (struct tcpcb *tp);
194
195 /*
196 * called on the receipt of in-sequence ack during congestion
197 * avoidance phase
198 */
199 void (*congestion_avd) (struct tcpcb *tp, struct tcphdr *th);
200
201 /* called on the receipt of a valid ack */
202 void (*ack_rcvd) (struct tcpcb *tp, struct tcphdr *th);
203
204 /* called before entering FR */
205 void (*pre_fr) (struct tcpcb *tp);
206
207 /* after exiting FR */
208 void (*post_fr) (struct tcpcb *tp, struct tcphdr *th);
209
210 /* perform tasks when data transfer resumes after an idle period */
211 void (*after_idle) (struct tcpcb *tp);
212
213 /* perform tasks when the connection's retransmit timer expires */
214 void (*after_timeout) (struct tcpcb *tp);
215
216 /* Whether or not to delay the ack */
217 int (*delay_ack)(struct tcpcb *tp, struct tcphdr *th);
218
219 /* called to process ECN markings, used by Prague only */
220 void (*process_ecn) (struct tcpcb *tp, struct tcphdr *th, uint32_t new_bytes_marked, uint32_t packets_marked, uint32_t packets_acked);
221
222 /* called to set bytes acked in this ACK which are later update to exclude CE marked bytes */
223 void (*set_bytes_acked) (struct tcpcb *tp, uint32_t acked);
224
225 /* Switch a connection to this CC algorithm after sending some packets */
226 void (*switch_to)(struct tcpcb *tp);
227 } __attribute__((aligned(4)));
228
229 extern struct tcp_cc_algo* tcp_cc_algo_list[TCP_CC_ALGO_COUNT];
230
231 #define CC_ALGO(tp) (tcp_cc_algo_list[tp->tcp_cc_index])
232 #define TCP_CC_CWND_INIT_PKTS 10
233 #define TCP_CC_CWND_INIT_BYTES 4380
234 /*
235 * The congestion window will have to be reset after a
236 * non-validated period -- currently set to 3 minutes
237 */
238 #define TCP_CC_CWND_NONVALIDATED_PERIOD (3 * 60 * TCP_RETRANSHZ)
239
240 /* Less than BE congestion control algo for receive window */
241 struct tcp_rcv_cc_algo {
242 char name[TCP_CA_NAME_MAX];
243 _Atomic uint32_t num_sockets;
244 uint32_t flags;
245
246 /* init the congestion algorithm for the specified control block */
247 void (*init) (struct tcpcb *tp);
248
249 /*
250 * cleanup any state that is stored in the connection
251 * related to the algorithm
252 */
253 void (*cleanup) (struct tcpcb *tp);
254
255 /* initialize rwnd at the start of a connection */
256 void (*rwnd_init) (struct tcpcb *tp);
257
258 /* called on the receipt of valid data */
259 void (*data_rcvd) (struct tcpcb *tp, struct tcphdr *th,
260 struct tcpopt *to, uint32_t segment_len);
261
262 uint32_t (*get_rlwin) (struct tcpcb *tp);
263
264 /* perform tasks when data transfer resumes after an idle period */
265 void (*after_idle) (struct tcpcb *tp);
266
267 /* called when we switch from foreground to background */
268 void (*switch_to) (struct tcpcb *tp);
269 } __attribute__((aligned(4)));
270
271 extern struct tcp_rcv_cc_algo tcp_cc_rledbat;
272
273 extern void tcp_cc_init(void);
274 extern void tcp_cc_resize_sndbuf(struct tcpcb *tp);
275 extern void tcp_bad_rexmt_fix_sndbuf(struct tcpcb *tp);
276 extern void tcp_cc_cwnd_init_or_reset(struct tcpcb *tp);
277 extern int tcp_cc_delay_ack(struct tcpcb *tp, struct tcphdr *th);
278 extern void tcp_cc_allocate_state(struct tcpcb *tp);
279 extern uint32_t tcp_cc_is_cwnd_nonvalidated(struct tcpcb *tp);
280 extern void tcp_cc_adjust_nonvalidated_cwnd(struct tcpcb *tp);
281 extern u_int32_t tcp_get_max_pipeack(struct tcpcb *tp);
282 extern void tcp_clear_pipeack_state(struct tcpcb *tp);
283
284 static inline uint32_t
tcp_initial_cwnd(struct tcpcb * tp)285 tcp_initial_cwnd(struct tcpcb *tp)
286 {
287 return TCP_CC_CWND_INIT_PKTS * tp->t_maxseg;
288 }
289
290 #endif /* KERNEL_PRIVATE */
291 #endif /* _NETINET_CC_H_ */
292