in6_proto.c revision 1.13 1 1.13 itojun /* $NetBSD: in6_proto.c,v 1.13 2000/02/06 12:49:45 itojun Exp $ */
2 1.3 thorpej
3 1.2 itojun /*
4 1.2 itojun * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
5 1.2 itojun * All rights reserved.
6 1.2 itojun *
7 1.2 itojun * Redistribution and use in source and binary forms, with or without
8 1.2 itojun * modification, are permitted provided that the following conditions
9 1.2 itojun * are met:
10 1.2 itojun * 1. Redistributions of source code must retain the above copyright
11 1.2 itojun * notice, this list of conditions and the following disclaimer.
12 1.2 itojun * 2. Redistributions in binary form must reproduce the above copyright
13 1.2 itojun * notice, this list of conditions and the following disclaimer in the
14 1.2 itojun * documentation and/or other materials provided with the distribution.
15 1.2 itojun * 3. Neither the name of the project nor the names of its contributors
16 1.2 itojun * may be used to endorse or promote products derived from this software
17 1.2 itojun * without specific prior written permission.
18 1.2 itojun *
19 1.2 itojun * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
20 1.2 itojun * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 1.2 itojun * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 1.2 itojun * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
23 1.2 itojun * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 1.2 itojun * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 1.2 itojun * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 1.2 itojun * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 1.2 itojun * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 1.2 itojun * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 1.2 itojun * SUCH DAMAGE.
30 1.2 itojun */
31 1.2 itojun
32 1.2 itojun /*
33 1.2 itojun * Copyright (c) 1982, 1986, 1993
34 1.2 itojun * The Regents of the University of California. All rights reserved.
35 1.2 itojun *
36 1.2 itojun * Redistribution and use in source and binary forms, with or without
37 1.2 itojun * modification, are permitted provided that the following conditions
38 1.2 itojun * are met:
39 1.2 itojun * 1. Redistributions of source code must retain the above copyright
40 1.2 itojun * notice, this list of conditions and the following disclaimer.
41 1.2 itojun * 2. Redistributions in binary form must reproduce the above copyright
42 1.2 itojun * notice, this list of conditions and the following disclaimer in the
43 1.2 itojun * documentation and/or other materials provided with the distribution.
44 1.2 itojun * 3. All advertising materials mentioning features or use of this software
45 1.2 itojun * must display the following acknowledgement:
46 1.2 itojun * This product includes software developed by the University of
47 1.2 itojun * California, Berkeley and its contributors.
48 1.2 itojun * 4. Neither the name of the University nor the names of its contributors
49 1.2 itojun * may be used to endorse or promote products derived from this software
50 1.2 itojun * without specific prior written permission.
51 1.2 itojun *
52 1.2 itojun * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
53 1.2 itojun * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
54 1.2 itojun * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
55 1.2 itojun * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
56 1.2 itojun * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
57 1.2 itojun * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
58 1.2 itojun * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
59 1.2 itojun * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
60 1.2 itojun * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
61 1.2 itojun * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
62 1.2 itojun * SUCH DAMAGE.
63 1.2 itojun *
64 1.2 itojun * @(#)in_proto.c 8.1 (Berkeley) 6/10/93
65 1.2 itojun */
66 1.2 itojun
67 1.2 itojun #include "opt_inet.h"
68 1.4 thorpej #include "opt_ipsec.h"
69 1.2 itojun
70 1.2 itojun #include <sys/param.h>
71 1.2 itojun #include <sys/socket.h>
72 1.2 itojun #include <sys/protosw.h>
73 1.2 itojun #include <sys/kernel.h>
74 1.2 itojun #include <sys/domain.h>
75 1.2 itojun #include <sys/mbuf.h>
76 1.2 itojun
77 1.2 itojun #include <net/if.h>
78 1.2 itojun #include <net/radix.h>
79 1.2 itojun #include <net/route.h>
80 1.2 itojun
81 1.2 itojun #include <netinet/in.h>
82 1.2 itojun #include <netinet/in_systm.h>
83 1.2 itojun #include <netinet/in_var.h>
84 1.12 itojun #ifndef TCP6
85 1.2 itojun #include <netinet/ip.h>
86 1.2 itojun #include <netinet/ip_var.h>
87 1.2 itojun #endif
88 1.12 itojun #ifndef TCP6
89 1.2 itojun #include <netinet/in_pcb.h>
90 1.2 itojun #endif
91 1.13 itojun #include <netinet/ip6.h>
92 1.2 itojun #include <netinet6/ip6_var.h>
93 1.13 itojun #include <netinet/icmp6.h>
94 1.2 itojun #include <netinet6/in6_pcb.h>
95 1.2 itojun
96 1.12 itojun #ifndef TCP6
97 1.2 itojun #include <netinet/tcp.h>
98 1.2 itojun #include <netinet/tcp_fsm.h>
99 1.2 itojun #include <netinet/tcp_seq.h>
100 1.2 itojun #include <netinet/tcp_timer.h>
101 1.2 itojun #include <netinet/tcp_var.h>
102 1.2 itojun #include <netinet/tcpip.h>
103 1.2 itojun #include <netinet/tcp_debug.h>
104 1.2 itojun #else
105 1.2 itojun #include <netinet6/tcp6.h>
106 1.2 itojun #include <netinet6/tcp6_fsm.h>
107 1.2 itojun #include <netinet6/tcp6_seq.h>
108 1.2 itojun #include <netinet6/tcp6_timer.h>
109 1.2 itojun #include <netinet6/tcp6_var.h>
110 1.2 itojun #endif
111 1.2 itojun
112 1.2 itojun #include <netinet6/udp6.h>
113 1.2 itojun #include <netinet6/udp6_var.h>
114 1.2 itojun
115 1.2 itojun #include <netinet6/pim6_var.h>
116 1.2 itojun
117 1.2 itojun #include <netinet6/nd6.h>
118 1.9 itojun
119 1.2 itojun
120 1.2 itojun #ifdef IPSEC
121 1.9 itojun #include <netinet6/ipsec.h>
122 1.2 itojun #include <netinet6/ah.h>
123 1.2 itojun #ifdef IPSEC_ESP
124 1.2 itojun #include <netinet6/esp.h>
125 1.2 itojun #endif
126 1.2 itojun #include <netinet6/ipcomp.h>
127 1.2 itojun #endif /*IPSEC*/
128 1.2 itojun
129 1.2 itojun #include <netinet6/ip6protosw.h>
130 1.2 itojun
131 1.2 itojun #include "gif.h"
132 1.2 itojun #if NGIF > 0
133 1.2 itojun #include <netinet6/in6_gif.h>
134 1.2 itojun #endif
135 1.2 itojun
136 1.9 itojun #include <net/net_osdep.h>
137 1.9 itojun
138 1.2 itojun #define offsetof(type, member) ((size_t)(&((type *)0)->member))
139 1.2 itojun
140 1.2 itojun /*
141 1.2 itojun * TCP/IP protocol family: IP6, ICMP6, UDP, TCP.
142 1.2 itojun */
143 1.2 itojun
144 1.2 itojun extern struct domain inet6domain;
145 1.2 itojun
146 1.2 itojun struct ip6protosw inet6sw[] = {
147 1.2 itojun { 0, &inet6domain, IPPROTO_IPV6, 0,
148 1.2 itojun 0, 0, 0, 0,
149 1.2 itojun 0,
150 1.9 itojun ip6_init, 0, frag6_slowtimo, frag6_drain,
151 1.9 itojun ip6_sysctl,
152 1.2 itojun },
153 1.2 itojun { SOCK_DGRAM, &inet6domain, IPPROTO_UDP, PR_ATOMIC | PR_ADDR,
154 1.2 itojun udp6_input, 0, udp6_ctlinput, ip6_ctloutput,
155 1.12 itojun udp6_usrreq, udp6_init,
156 1.9 itojun 0, 0, 0,
157 1.9 itojun udp6_sysctl,
158 1.2 itojun },
159 1.2 itojun #ifdef TCP6
160 1.9 itojun { SOCK_STREAM, &inet6domain, IPPROTO_TCP, PR_CONNREQUIRED|PR_WANTRCVD|PR_LISTEN,
161 1.2 itojun tcp6_input, 0, tcp6_ctlinput, tcp6_ctloutput,
162 1.2 itojun tcp6_usrreq,
163 1.9 itojun tcp6_init, tcp6_fasttimo, tcp6_slowtimo, tcp6_drain,
164 1.9 itojun tcp6_sysctl,
165 1.2 itojun },
166 1.2 itojun #else
167 1.9 itojun { SOCK_STREAM, &inet6domain, IPPROTO_TCP, PR_CONNREQUIRED|PR_WANTRCVD|PR_LISTEN,
168 1.2 itojun tcp6_input, 0, tcp6_ctlinput, tcp_ctloutput,
169 1.2 itojun tcp_usrreq,
170 1.9 itojun #ifdef INET /* don't call timeout routines twice */
171 1.9 itojun tcp_init, 0, 0, tcp_drain,
172 1.9 itojun #else
173 1.9 itojun tcp_init, tcp_fasttimo, tcp_slowtimo, tcp_drain,
174 1.9 itojun #endif
175 1.9 itojun tcp_sysctl,
176 1.2 itojun },
177 1.9 itojun #endif /*TCP6*/
178 1.2 itojun { SOCK_RAW, &inet6domain, IPPROTO_RAW, PR_ATOMIC | PR_ADDR,
179 1.2 itojun rip6_input, rip6_output, 0, rip6_ctloutput,
180 1.2 itojun rip6_usrreq,
181 1.9 itojun 0, 0, 0, 0,
182 1.2 itojun },
183 1.2 itojun { SOCK_RAW, &inet6domain, IPPROTO_ICMPV6, PR_ATOMIC | PR_ADDR,
184 1.2 itojun icmp6_input, rip6_output, 0, rip6_ctloutput,
185 1.2 itojun rip6_usrreq,
186 1.9 itojun icmp6_init, icmp6_fasttimo, 0, 0,
187 1.9 itojun icmp6_sysctl,
188 1.2 itojun },
189 1.2 itojun { SOCK_RAW, &inet6domain, IPPROTO_DSTOPTS,PR_ATOMIC|PR_ADDR,
190 1.2 itojun dest6_input, 0, 0, 0,
191 1.2 itojun 0,
192 1.2 itojun 0, 0, 0, 0,
193 1.2 itojun },
194 1.2 itojun { SOCK_RAW, &inet6domain, IPPROTO_ROUTING,PR_ATOMIC|PR_ADDR,
195 1.2 itojun route6_input, 0, 0, 0,
196 1.2 itojun 0,
197 1.2 itojun 0, 0, 0, 0,
198 1.2 itojun },
199 1.2 itojun { SOCK_RAW, &inet6domain, IPPROTO_FRAGMENT,PR_ATOMIC|PR_ADDR,
200 1.2 itojun frag6_input, 0, 0, 0,
201 1.2 itojun 0,
202 1.2 itojun 0, 0, 0, 0,
203 1.2 itojun },
204 1.2 itojun #ifdef IPSEC
205 1.2 itojun { SOCK_RAW, &inet6domain, IPPROTO_AH, PR_ATOMIC|PR_ADDR,
206 1.2 itojun ah6_input, 0, 0, 0,
207 1.2 itojun 0,
208 1.9 itojun 0, 0, 0, 0,
209 1.9 itojun ipsec6_sysctl,
210 1.2 itojun },
211 1.2 itojun #ifdef IPSEC_ESP
212 1.2 itojun { SOCK_RAW, &inet6domain, IPPROTO_ESP, PR_ATOMIC|PR_ADDR,
213 1.2 itojun esp6_input, 0, 0, 0,
214 1.2 itojun 0,
215 1.9 itojun 0, 0, 0, 0,
216 1.9 itojun ipsec6_sysctl,
217 1.2 itojun },
218 1.2 itojun #endif
219 1.2 itojun { SOCK_RAW, &inet6domain, IPPROTO_IPCOMP, PR_ATOMIC|PR_ADDR,
220 1.2 itojun ipcomp6_input, 0, 0, 0,
221 1.2 itojun 0,
222 1.9 itojun 0, 0, 0, 0,
223 1.9 itojun ipsec6_sysctl,
224 1.2 itojun },
225 1.2 itojun #endif /* IPSEC */
226 1.2 itojun #if NGIF > 0
227 1.2 itojun { SOCK_RAW, &inet6domain, IPPROTO_IPV4, PR_ATOMIC|PR_ADDR,
228 1.2 itojun in6_gif_input,0, 0, 0,
229 1.2 itojun 0,
230 1.2 itojun 0, 0, 0, 0,
231 1.2 itojun },
232 1.2 itojun #ifdef INET6
233 1.2 itojun { SOCK_RAW, &inet6domain, IPPROTO_IPV6, PR_ATOMIC|PR_ADDR,
234 1.2 itojun in6_gif_input,0, 0, 0,
235 1.2 itojun 0,
236 1.2 itojun 0, 0, 0, 0,
237 1.2 itojun },
238 1.2 itojun #endif /* INET6 */
239 1.2 itojun #endif /* GIF */
240 1.2 itojun { SOCK_RAW, &inet6domain, IPPROTO_PIM, PR_ATOMIC|PR_ADDR,
241 1.2 itojun pim6_input, rip6_output, 0, rip6_ctloutput,
242 1.2 itojun rip6_usrreq,
243 1.2 itojun 0, 0, 0, 0,
244 1.2 itojun },
245 1.2 itojun /* raw wildcard */
246 1.2 itojun { SOCK_RAW, &inet6domain, 0, PR_ATOMIC | PR_ADDR,
247 1.2 itojun rip6_input, rip6_output, 0, rip6_ctloutput,
248 1.9 itojun rip6_usrreq, rip6_init,
249 1.9 itojun 0, 0, 0,
250 1.2 itojun },
251 1.2 itojun };
252 1.2 itojun
253 1.2 itojun struct domain inet6domain =
254 1.2 itojun { AF_INET6, "internet6", 0, 0, 0,
255 1.2 itojun (struct protosw *)inet6sw,
256 1.2 itojun (struct protosw *)&inet6sw[sizeof(inet6sw)/sizeof(inet6sw[0])], 0,
257 1.9 itojun rn_inithead,
258 1.9 itojun offsetof(struct sockaddr_in6, sin6_addr) << 3,
259 1.2 itojun sizeof(struct sockaddr_in6) };
260 1.2 itojun
261 1.2 itojun /*
262 1.2 itojun * Internet configuration info
263 1.2 itojun */
264 1.2 itojun #ifndef IPV6FORWARDING
265 1.2 itojun #ifdef GATEWAY6
266 1.2 itojun #define IPV6FORWARDING 1 /* forward IP6 packets not for us */
267 1.2 itojun #else
268 1.2 itojun #define IPV6FORWARDING 0 /* don't forward IP6 packets not for us */
269 1.2 itojun #endif /* GATEWAY6 */
270 1.2 itojun #endif /* !IPV6FORWARDING */
271 1.2 itojun
272 1.2 itojun #ifndef IPV6_SENDREDIRECTS
273 1.2 itojun #define IPV6_SENDREDIRECTS 1
274 1.2 itojun #endif
275 1.2 itojun
276 1.2 itojun int ip6_forwarding = IPV6FORWARDING; /* act as router? */
277 1.2 itojun int ip6_sendredirects = IPV6_SENDREDIRECTS;
278 1.2 itojun int ip6_defhlim = IPV6_DEFHLIM;
279 1.2 itojun int ip6_defmcasthlim = IPV6_DEFAULT_MULTICAST_HOPS;
280 1.2 itojun int ip6_accept_rtadv = 0; /* "IPV6FORWARDING ? 0 : 1" is dangerous */
281 1.2 itojun int ip6_maxfragpackets = 200;
282 1.2 itojun int ip6_log_interval = 5;
283 1.2 itojun int ip6_hdrnestlimit = 50; /* appropriate? */
284 1.2 itojun int ip6_dad_count = 1; /* DupAddrDetectionTransmits */
285 1.2 itojun u_int32_t ip6_flow_seq;
286 1.2 itojun int ip6_auto_flowlabel = 1;
287 1.2 itojun #if NGIF > 0
288 1.2 itojun int ip6_gif_hlim = GIF_HLIM;
289 1.2 itojun #else
290 1.2 itojun int ip6_gif_hlim = 0;
291 1.2 itojun #endif
292 1.9 itojun int ip6_use_deprecated = 1; /* allow deprecated addr (RFC2462 5.5.4) */
293 1.9 itojun int ip6_rr_prune = 5; /* router renumbering prefix
294 1.9 itojun * walk list every 5 sec. */
295 1.12 itojun #ifndef INET6_BINDV6ONLY
296 1.11 itojun int ip6_bindv6only = 1;
297 1.11 itojun #endif
298 1.11 itojun
299 1.5 itojun u_int32_t ip6_id = 0UL;
300 1.2 itojun int ip6_keepfaith = 0;
301 1.2 itojun time_t ip6_log_time = (time_t)0L;
302 1.2 itojun
303 1.2 itojun /* icmp6 */
304 1.9 itojun /*
305 1.9 itojun * BSDI4 defines these variables in in_proto.c...
306 1.9 itojun * XXX: what if we don't define INET? Should we define pmtu6_expire
307 1.9 itojun * or so? (jinmei (at) kame.net 19990310)
308 1.9 itojun */
309 1.2 itojun int pmtu_expire = 60*10;
310 1.2 itojun int pmtu_probe = 60*2;
311 1.2 itojun
312 1.2 itojun /* raw IP6 parameters */
313 1.2 itojun /*
314 1.2 itojun * Nominal space allocated to a raw ip socket.
315 1.2 itojun */
316 1.2 itojun #define RIPV6SNDQ 8192
317 1.2 itojun #define RIPV6RCVQ 8192
318 1.2 itojun
319 1.2 itojun u_long rip6_sendspace = RIPV6SNDQ;
320 1.2 itojun u_long rip6_recvspace = RIPV6RCVQ;
321 1.2 itojun
322 1.2 itojun /* ICMPV6 parameters */
323 1.2 itojun int icmp6_rediraccept = 1; /* accept and process redirects */
324 1.2 itojun int icmp6_redirtimeout = 10 * 60; /* 10 minutes */
325 1.2 itojun u_int icmp6errratelim = 1000; /* 1000usec = 1msec */
326 1.10 itojun int icmp6_nodeinfo = 1; /* enable/disable NI response */
327 1.2 itojun
328 1.2 itojun #ifdef TCP6
329 1.2 itojun /* TCP on IP6 parameters */
330 1.2 itojun int tcp6_sendspace = 1024 * 8;
331 1.2 itojun int tcp6_recvspace = 1024 * 8;
332 1.2 itojun int tcp6_mssdflt = TCP6_MSS;
333 1.2 itojun int tcp6_rttdflt = TCP6TV_SRTTDFLT / PR_SLOWHZ;
334 1.2 itojun int tcp6_do_rfc1323 = 1;
335 1.2 itojun int tcp6_conntimeo = TCP6TV_KEEP_INIT; /* initial connection timeout */
336 1.2 itojun int tcp6_43maxseg = 0;
337 1.2 itojun int tcp6_pmtu = 0;
338 1.2 itojun
339 1.2 itojun /*
340 1.2 itojun * Parameters for keepalive option.
341 1.2 itojun * Connections for which SO_KEEPALIVE is set will be probed
342 1.2 itojun * after being idle for a time of tcp6_keepidle (in units of PR_SLOWHZ).
343 1.2 itojun * Starting at that time, the connection is probed at intervals
344 1.2 itojun * of tcp6_keepintvl (same units) until a response is received
345 1.2 itojun * or until tcp6_keepcnt probes have been made, at which time
346 1.2 itojun * the connection is dropped. Note that a tcp6_keepidle value
347 1.2 itojun * under 2 hours is nonconformant with RFC-1122, Internet Host Requirements.
348 1.2 itojun */
349 1.2 itojun int tcp6_keepidle = TCP6TV_KEEP_IDLE; /* time before probing idle */
350 1.2 itojun int tcp6_keepintvl = TCP6TV_KEEPINTVL; /* interval betwn idle probes */
351 1.2 itojun int tcp6_keepcnt = TCP6TV_KEEPCNT; /* max idle probes */
352 1.2 itojun int tcp6_maxpersistidle = TCP6TV_KEEP_IDLE; /* max idle time in persist */
353 1.2 itojun
354 1.2 itojun #ifndef INET_SERVER
355 1.2 itojun #define TCP6_LISTEN_HASH_SIZE 17
356 1.2 itojun #define TCP6_CONN_HASH_SIZE 97
357 1.2 itojun #define TCP6_SYN_HASH_SIZE 293
358 1.2 itojun #define TCP6_SYN_BUCKET_SIZE 35
359 1.2 itojun #else
360 1.2 itojun #define TCP6_LISTEN_HASH_SIZE 97
361 1.2 itojun #define TCP6_CONN_HASH_SIZE 9973
362 1.2 itojun #define TCP6_SYN_HASH_SIZE 997
363 1.2 itojun #define TCP6_SYN_BUCKET_SIZE 35
364 1.2 itojun #endif
365 1.2 itojun int tcp6_listen_hash_size = TCP6_LISTEN_HASH_SIZE;
366 1.2 itojun int tcp6_conn_hash_size = TCP6_CONN_HASH_SIZE;
367 1.2 itojun struct tcp6_hash_list tcp6_listen_hash[TCP6_LISTEN_HASH_SIZE],
368 1.2 itojun tcp6_conn_hash[TCP6_CONN_HASH_SIZE];
369 1.2 itojun
370 1.2 itojun int tcp6_syn_cache_size = TCP6_SYN_HASH_SIZE;
371 1.2 itojun int tcp6_syn_cache_limit = TCP6_SYN_HASH_SIZE*TCP6_SYN_BUCKET_SIZE;
372 1.2 itojun int tcp6_syn_bucket_limit = 3*TCP6_SYN_BUCKET_SIZE;
373 1.2 itojun struct syn_cache_head6 tcp6_syn_cache[TCP6_SYN_HASH_SIZE];
374 1.2 itojun struct syn_cache_head6 *tcp6_syn_cache_first;
375 1.2 itojun int tcp6_syn_cache_interval = 8; /* runs timer every 4 seconds */
376 1.2 itojun int tcp6_syn_cache_timeo = TCP6TV_KEEP_INIT;
377 1.2 itojun
378 1.2 itojun /*
379 1.2 itojun * Parameters for computing a desirable data segment size
380 1.2 itojun * given an upper bound (either interface MTU, or peer's MSS option)_.
381 1.2 itojun * As applications tend to use a buffer size that is a multiple
382 1.2 itojun * of kilobytes, try for something that divides evenly. However,
383 1.2 itojun * do not round down too much.
384 1.2 itojun *
385 1.2 itojun * Round segment size down to a multiple of TCP6_ROUNDSIZE if this
386 1.2 itojun * does not result in lowering by more than (size/TCP6_ROUNDFRAC).
387 1.2 itojun * For example, round 536 to 512. Older versions of the system
388 1.2 itojun * effectively used MCLBYTES (1K or 2K) as TCP6_ROUNDSIZE, with
389 1.2 itojun * a value of 1 for TCP6_ROUNDFRAC (eliminating its effect).
390 1.2 itojun * We round to a multiple of 256 for SLIP.
391 1.2 itojun */
392 1.2 itojun #ifndef TCP6_ROUNDSIZE
393 1.2 itojun #define TCP6_ROUNDSIZE 256 /* round to multiple of 256 */
394 1.2 itojun #endif
395 1.2 itojun #ifndef TCP6_ROUNDFRAC
396 1.2 itojun #define TCP6_ROUNDFRAC 10 /* round down at most N/10, or 10% */
397 1.2 itojun #endif
398 1.2 itojun
399 1.2 itojun int tcp6_roundsize = TCP6_ROUNDSIZE;
400 1.2 itojun int tcp6_roundfrac = TCP6_ROUNDFRAC;
401 1.2 itojun #endif /*TCP6*/
402 1.2 itojun
403 1.2 itojun /* UDP on IP6 parameters */
404 1.2 itojun int udp6_sendspace = 9216; /* really max datagram size */
405 1.2 itojun int udp6_recvspace = 40 * (1024 + sizeof(struct sockaddr_in6));
406 1.2 itojun /* 40 1K datagrams */
407