1 | /* $NetBSD: tcp_subr.c,v 1.267 2016/11/09 03:33:30 ozaki-r Exp $ */ |
2 | |
3 | /* |
4 | * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. |
5 | * All rights reserved. |
6 | * |
7 | * Redistribution and use in source and binary forms, with or without |
8 | * modification, are permitted provided that the following conditions |
9 | * are met: |
10 | * 1. Redistributions of source code must retain the above copyright |
11 | * notice, this list of conditions and the following disclaimer. |
12 | * 2. Redistributions in binary form must reproduce the above copyright |
13 | * notice, this list of conditions and the following disclaimer in the |
14 | * documentation and/or other materials provided with the distribution. |
15 | * 3. Neither the name of the project nor the names of its contributors |
16 | * may be used to endorse or promote products derived from this software |
17 | * without specific prior written permission. |
18 | * |
19 | * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND |
20 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
21 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
22 | * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE |
23 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
24 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
25 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
26 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
27 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
28 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
29 | * SUCH DAMAGE. |
30 | */ |
31 | |
32 | /*- |
33 | * Copyright (c) 1997, 1998, 2000, 2001, 2008 The NetBSD Foundation, Inc. |
34 | * All rights reserved. |
35 | * |
36 | * This code is derived from software contributed to The NetBSD Foundation |
37 | * by Jason R. Thorpe and Kevin M. Lahey of the Numerical Aerospace Simulation |
38 | * Facility, NASA Ames Research Center. |
39 | * |
40 | * Redistribution and use in source and binary forms, with or without |
41 | * modification, are permitted provided that the following conditions |
42 | * are met: |
43 | * 1. Redistributions of source code must retain the above copyright |
44 | * notice, this list of conditions and the following disclaimer. |
45 | * 2. Redistributions in binary form must reproduce the above copyright |
46 | * notice, this list of conditions and the following disclaimer in the |
47 | * documentation and/or other materials provided with the distribution. |
48 | * |
49 | * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS |
50 | * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED |
51 | * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
52 | * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS |
53 | * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
54 | * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
55 | * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
56 | * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
57 | * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
58 | * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
59 | * POSSIBILITY OF SUCH DAMAGE. |
60 | */ |
61 | |
62 | /* |
63 | * Copyright (c) 1982, 1986, 1988, 1990, 1993, 1995 |
64 | * The Regents of the University of California. All rights reserved. |
65 | * |
66 | * Redistribution and use in source and binary forms, with or without |
67 | * modification, are permitted provided that the following conditions |
68 | * are met: |
69 | * 1. Redistributions of source code must retain the above copyright |
70 | * notice, this list of conditions and the following disclaimer. |
71 | * 2. Redistributions in binary form must reproduce the above copyright |
72 | * notice, this list of conditions and the following disclaimer in the |
73 | * documentation and/or other materials provided with the distribution. |
74 | * 3. Neither the name of the University nor the names of its contributors |
75 | * may be used to endorse or promote products derived from this software |
76 | * without specific prior written permission. |
77 | * |
78 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
79 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
80 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
81 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
82 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
83 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
84 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
85 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
86 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
87 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
88 | * SUCH DAMAGE. |
89 | * |
90 | * @(#)tcp_subr.c 8.2 (Berkeley) 5/24/95 |
91 | */ |
92 | |
93 | #include <sys/cdefs.h> |
94 | __KERNEL_RCSID(0, "$NetBSD: tcp_subr.c,v 1.267 2016/11/09 03:33:30 ozaki-r Exp $" ); |
95 | |
96 | #ifdef _KERNEL_OPT |
97 | #include "opt_inet.h" |
98 | #include "opt_ipsec.h" |
99 | #include "opt_tcp_compat_42.h" |
100 | #include "opt_inet_csum.h" |
101 | #include "opt_mbuftrace.h" |
102 | #endif |
103 | |
104 | #include <sys/param.h> |
105 | #include <sys/atomic.h> |
106 | #include <sys/proc.h> |
107 | #include <sys/systm.h> |
108 | #include <sys/mbuf.h> |
109 | #include <sys/once.h> |
110 | #include <sys/socket.h> |
111 | #include <sys/socketvar.h> |
112 | #include <sys/protosw.h> |
113 | #include <sys/errno.h> |
114 | #include <sys/kernel.h> |
115 | #include <sys/pool.h> |
116 | #include <sys/md5.h> |
117 | #include <sys/cprng.h> |
118 | |
119 | #include <net/route.h> |
120 | #include <net/if.h> |
121 | |
122 | #include <netinet/in.h> |
123 | #include <netinet/in_systm.h> |
124 | #include <netinet/ip.h> |
125 | #include <netinet/in_pcb.h> |
126 | #include <netinet/ip_var.h> |
127 | #include <netinet/ip_icmp.h> |
128 | |
129 | #ifdef INET6 |
130 | #ifndef INET |
131 | #include <netinet/in.h> |
132 | #endif |
133 | #include <netinet/ip6.h> |
134 | #include <netinet6/in6_pcb.h> |
135 | #include <netinet6/ip6_var.h> |
136 | #include <netinet6/in6_var.h> |
137 | #include <netinet6/ip6protosw.h> |
138 | #include <netinet/icmp6.h> |
139 | #include <netinet6/nd6.h> |
140 | #endif |
141 | |
142 | #include <netinet/tcp.h> |
143 | #include <netinet/tcp_fsm.h> |
144 | #include <netinet/tcp_seq.h> |
145 | #include <netinet/tcp_timer.h> |
146 | #include <netinet/tcp_var.h> |
147 | #include <netinet/tcp_vtw.h> |
148 | #include <netinet/tcp_private.h> |
149 | #include <netinet/tcp_congctl.h> |
150 | #include <netinet/tcpip.h> |
151 | |
152 | #ifdef IPSEC |
153 | #include <netipsec/ipsec.h> |
154 | #include <netipsec/xform.h> |
155 | #ifdef INET6 |
156 | #include <netipsec/ipsec6.h> |
157 | #endif |
158 | #include <netipsec/key.h> |
159 | #endif /* IPSEC*/ |
160 | |
161 | |
162 | struct inpcbtable tcbtable; /* head of queue of active tcpcb's */ |
163 | u_int32_t tcp_now; /* slow ticks, for RFC 1323 timestamps */ |
164 | |
165 | percpu_t *tcpstat_percpu; |
166 | |
167 | /* patchable/settable parameters for tcp */ |
168 | int tcp_mssdflt = TCP_MSS; |
169 | int tcp_minmss = TCP_MINMSS; |
170 | int tcp_rttdflt = TCPTV_SRTTDFLT / PR_SLOWHZ; |
171 | int tcp_do_rfc1323 = 1; /* window scaling / timestamps (obsolete) */ |
172 | int tcp_do_rfc1948 = 0; /* ISS by cryptographic hash */ |
173 | int tcp_do_sack = 1; /* selective acknowledgement */ |
174 | int tcp_do_win_scale = 1; /* RFC1323 window scaling */ |
175 | int tcp_do_timestamps = 1; /* RFC1323 timestamps */ |
176 | int tcp_ack_on_push = 0; /* set to enable immediate ACK-on-PUSH */ |
177 | int tcp_do_ecn = 0; /* Explicit Congestion Notification */ |
178 | #ifndef TCP_INIT_WIN |
179 | #define TCP_INIT_WIN 4 /* initial slow start window */ |
180 | #endif |
181 | #ifndef TCP_INIT_WIN_LOCAL |
182 | #define TCP_INIT_WIN_LOCAL 4 /* initial slow start window for local nets */ |
183 | #endif |
184 | /* |
185 | * Up to 5 we scale linearly, to reach 3 * 1460; then (iw) * 1460. |
186 | * This is to simulate current behavior for iw == 4 |
187 | */ |
188 | int tcp_init_win_max[] = { |
189 | 1 * 1460, |
190 | 1 * 1460, |
191 | 2 * 1460, |
192 | 2 * 1460, |
193 | 3 * 1460, |
194 | 5 * 1460, |
195 | 6 * 1460, |
196 | 7 * 1460, |
197 | 8 * 1460, |
198 | 9 * 1460, |
199 | 10 * 1460 |
200 | }; |
201 | int tcp_init_win = TCP_INIT_WIN; |
202 | int tcp_init_win_local = TCP_INIT_WIN_LOCAL; |
203 | int tcp_mss_ifmtu = 0; |
204 | #ifdef TCP_COMPAT_42 |
205 | int tcp_compat_42 = 1; |
206 | #else |
207 | int tcp_compat_42 = 0; |
208 | #endif |
209 | int tcp_rst_ppslim = 100; /* 100pps */ |
210 | int tcp_ackdrop_ppslim = 100; /* 100pps */ |
211 | int tcp_do_loopback_cksum = 0; |
212 | int tcp_do_abc = 1; /* RFC3465 Appropriate byte counting. */ |
213 | int tcp_abc_aggressive = 1; /* 1: L=2*SMSS 0: L=1*SMSS */ |
214 | int tcp_sack_tp_maxholes = 32; |
215 | int tcp_sack_globalmaxholes = 1024; |
216 | int tcp_sack_globalholes = 0; |
217 | int tcp_ecn_maxretries = 1; |
218 | int tcp_msl_enable = 1; /* enable TIME_WAIT truncation */ |
219 | int tcp_msl_loop = PR_SLOWHZ; /* MSL for loopback */ |
220 | int tcp_msl_local = 5 * PR_SLOWHZ; /* MSL for 'local' */ |
221 | int tcp_msl_remote = TCPTV_MSL; /* MSL otherwise */ |
222 | int tcp_msl_remote_threshold = TCPTV_SRTTDFLT; /* RTT threshold */ |
223 | int tcp_rttlocal = 0; /* Use RTT to decide who's 'local' */ |
224 | |
225 | int tcp4_vtw_enable = 0; /* 1 to enable */ |
226 | int tcp6_vtw_enable = 0; /* 1 to enable */ |
227 | int tcp_vtw_was_enabled = 0; |
228 | int tcp_vtw_entries = 1 << 4; /* 16 vestigial TIME_WAIT entries */ |
229 | |
230 | /* tcb hash */ |
231 | #ifndef TCBHASHSIZE |
232 | #define TCBHASHSIZE 128 |
233 | #endif |
234 | int tcbhashsize = TCBHASHSIZE; |
235 | |
236 | /* syn hash parameters */ |
237 | #define TCP_SYN_HASH_SIZE 293 |
238 | #define TCP_SYN_BUCKET_SIZE 35 |
239 | int tcp_syn_cache_size = TCP_SYN_HASH_SIZE; |
240 | int tcp_syn_cache_limit = TCP_SYN_HASH_SIZE*TCP_SYN_BUCKET_SIZE; |
241 | int tcp_syn_bucket_limit = 3*TCP_SYN_BUCKET_SIZE; |
242 | struct syn_cache_head tcp_syn_cache[TCP_SYN_HASH_SIZE]; |
243 | |
244 | int tcp_freeq(struct tcpcb *); |
245 | static int tcp_iss_secret_init(void); |
246 | |
247 | #ifdef INET |
248 | static void tcp_mtudisc_callback(struct in_addr); |
249 | #endif |
250 | |
251 | #ifdef INET6 |
252 | void tcp6_mtudisc(struct in6pcb *, int); |
253 | #endif |
254 | |
255 | static struct pool tcpcb_pool; |
256 | |
257 | static int tcp_drainwanted; |
258 | |
259 | #ifdef TCP_CSUM_COUNTERS |
260 | #include <sys/device.h> |
261 | |
262 | #if defined(INET) |
263 | struct evcnt tcp_hwcsum_bad = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, |
264 | NULL, "tcp" , "hwcsum bad" ); |
265 | struct evcnt tcp_hwcsum_ok = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, |
266 | NULL, "tcp" , "hwcsum ok" ); |
267 | struct evcnt tcp_hwcsum_data = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, |
268 | NULL, "tcp" , "hwcsum data" ); |
269 | struct evcnt tcp_swcsum = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, |
270 | NULL, "tcp" , "swcsum" ); |
271 | |
272 | EVCNT_ATTACH_STATIC(tcp_hwcsum_bad); |
273 | EVCNT_ATTACH_STATIC(tcp_hwcsum_ok); |
274 | EVCNT_ATTACH_STATIC(tcp_hwcsum_data); |
275 | EVCNT_ATTACH_STATIC(tcp_swcsum); |
276 | #endif /* defined(INET) */ |
277 | |
278 | #if defined(INET6) |
279 | struct evcnt tcp6_hwcsum_bad = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, |
280 | NULL, "tcp6" , "hwcsum bad" ); |
281 | struct evcnt tcp6_hwcsum_ok = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, |
282 | NULL, "tcp6" , "hwcsum ok" ); |
283 | struct evcnt tcp6_hwcsum_data = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, |
284 | NULL, "tcp6" , "hwcsum data" ); |
285 | struct evcnt tcp6_swcsum = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, |
286 | NULL, "tcp6" , "swcsum" ); |
287 | |
288 | EVCNT_ATTACH_STATIC(tcp6_hwcsum_bad); |
289 | EVCNT_ATTACH_STATIC(tcp6_hwcsum_ok); |
290 | EVCNT_ATTACH_STATIC(tcp6_hwcsum_data); |
291 | EVCNT_ATTACH_STATIC(tcp6_swcsum); |
292 | #endif /* defined(INET6) */ |
293 | #endif /* TCP_CSUM_COUNTERS */ |
294 | |
295 | |
296 | #ifdef TCP_OUTPUT_COUNTERS |
297 | #include <sys/device.h> |
298 | |
299 | struct evcnt tcp_output_bigheader = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, |
300 | NULL, "tcp" , "output big header" ); |
301 | struct evcnt tcp_output_predict_hit = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, |
302 | NULL, "tcp" , "output predict hit" ); |
303 | struct evcnt tcp_output_predict_miss = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, |
304 | NULL, "tcp" , "output predict miss" ); |
305 | struct evcnt tcp_output_copysmall = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, |
306 | NULL, "tcp" , "output copy small" ); |
307 | struct evcnt tcp_output_copybig = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, |
308 | NULL, "tcp" , "output copy big" ); |
309 | struct evcnt tcp_output_refbig = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, |
310 | NULL, "tcp" , "output reference big" ); |
311 | |
312 | EVCNT_ATTACH_STATIC(tcp_output_bigheader); |
313 | EVCNT_ATTACH_STATIC(tcp_output_predict_hit); |
314 | EVCNT_ATTACH_STATIC(tcp_output_predict_miss); |
315 | EVCNT_ATTACH_STATIC(tcp_output_copysmall); |
316 | EVCNT_ATTACH_STATIC(tcp_output_copybig); |
317 | EVCNT_ATTACH_STATIC(tcp_output_refbig); |
318 | |
319 | #endif /* TCP_OUTPUT_COUNTERS */ |
320 | |
321 | #ifdef TCP_REASS_COUNTERS |
322 | #include <sys/device.h> |
323 | |
324 | struct evcnt tcp_reass_ = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, |
325 | NULL, "tcp_reass" , "calls" ); |
326 | struct evcnt tcp_reass_empty = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, |
327 | &tcp_reass_, "tcp_reass" , "insert into empty queue" ); |
328 | struct evcnt tcp_reass_iteration[8] = { |
329 | EVCNT_INITIALIZER(EVCNT_TYPE_MISC, &tcp_reass_, "tcp_reass" , ">7 iterations" ), |
330 | EVCNT_INITIALIZER(EVCNT_TYPE_MISC, &tcp_reass_, "tcp_reass" , "1 iteration" ), |
331 | EVCNT_INITIALIZER(EVCNT_TYPE_MISC, &tcp_reass_, "tcp_reass" , "2 iterations" ), |
332 | EVCNT_INITIALIZER(EVCNT_TYPE_MISC, &tcp_reass_, "tcp_reass" , "3 iterations" ), |
333 | EVCNT_INITIALIZER(EVCNT_TYPE_MISC, &tcp_reass_, "tcp_reass" , "4 iterations" ), |
334 | EVCNT_INITIALIZER(EVCNT_TYPE_MISC, &tcp_reass_, "tcp_reass" , "5 iterations" ), |
335 | EVCNT_INITIALIZER(EVCNT_TYPE_MISC, &tcp_reass_, "tcp_reass" , "6 iterations" ), |
336 | EVCNT_INITIALIZER(EVCNT_TYPE_MISC, &tcp_reass_, "tcp_reass" , "7 iterations" ), |
337 | }; |
338 | struct evcnt tcp_reass_prependfirst = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, |
339 | &tcp_reass_, "tcp_reass" , "prepend to first" ); |
340 | struct evcnt tcp_reass_prepend = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, |
341 | &tcp_reass_, "tcp_reass" , "prepend" ); |
342 | struct evcnt tcp_reass_insert = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, |
343 | &tcp_reass_, "tcp_reass" , "insert" ); |
344 | struct evcnt tcp_reass_inserttail = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, |
345 | &tcp_reass_, "tcp_reass" , "insert at tail" ); |
346 | struct evcnt tcp_reass_append = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, |
347 | &tcp_reass_, "tcp_reass" , "append" ); |
348 | struct evcnt tcp_reass_appendtail = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, |
349 | &tcp_reass_, "tcp_reass" , "append to tail fragment" ); |
350 | struct evcnt tcp_reass_overlaptail = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, |
351 | &tcp_reass_, "tcp_reass" , "overlap at end" ); |
352 | struct evcnt tcp_reass_overlapfront = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, |
353 | &tcp_reass_, "tcp_reass" , "overlap at start" ); |
354 | struct evcnt tcp_reass_segdup = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, |
355 | &tcp_reass_, "tcp_reass" , "duplicate segment" ); |
356 | struct evcnt tcp_reass_fragdup = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, |
357 | &tcp_reass_, "tcp_reass" , "duplicate fragment" ); |
358 | |
359 | EVCNT_ATTACH_STATIC(tcp_reass_); |
360 | EVCNT_ATTACH_STATIC(tcp_reass_empty); |
361 | EVCNT_ATTACH_STATIC2(tcp_reass_iteration, 0); |
362 | EVCNT_ATTACH_STATIC2(tcp_reass_iteration, 1); |
363 | EVCNT_ATTACH_STATIC2(tcp_reass_iteration, 2); |
364 | EVCNT_ATTACH_STATIC2(tcp_reass_iteration, 3); |
365 | EVCNT_ATTACH_STATIC2(tcp_reass_iteration, 4); |
366 | EVCNT_ATTACH_STATIC2(tcp_reass_iteration, 5); |
367 | EVCNT_ATTACH_STATIC2(tcp_reass_iteration, 6); |
368 | EVCNT_ATTACH_STATIC2(tcp_reass_iteration, 7); |
369 | EVCNT_ATTACH_STATIC(tcp_reass_prependfirst); |
370 | EVCNT_ATTACH_STATIC(tcp_reass_prepend); |
371 | EVCNT_ATTACH_STATIC(tcp_reass_insert); |
372 | EVCNT_ATTACH_STATIC(tcp_reass_inserttail); |
373 | EVCNT_ATTACH_STATIC(tcp_reass_append); |
374 | EVCNT_ATTACH_STATIC(tcp_reass_appendtail); |
375 | EVCNT_ATTACH_STATIC(tcp_reass_overlaptail); |
376 | EVCNT_ATTACH_STATIC(tcp_reass_overlapfront); |
377 | EVCNT_ATTACH_STATIC(tcp_reass_segdup); |
378 | EVCNT_ATTACH_STATIC(tcp_reass_fragdup); |
379 | |
380 | #endif /* TCP_REASS_COUNTERS */ |
381 | |
382 | #ifdef MBUFTRACE |
383 | struct mowner tcp_mowner = MOWNER_INIT("tcp" , "" ); |
384 | struct mowner tcp_rx_mowner = MOWNER_INIT("tcp" , "rx" ); |
385 | struct mowner tcp_tx_mowner = MOWNER_INIT("tcp" , "tx" ); |
386 | struct mowner tcp_sock_mowner = MOWNER_INIT("tcp" , "sock" ); |
387 | struct mowner tcp_sock_rx_mowner = MOWNER_INIT("tcp" , "sock rx" ); |
388 | struct mowner tcp_sock_tx_mowner = MOWNER_INIT("tcp" , "sock tx" ); |
389 | #endif |
390 | |
391 | callout_t tcp_slowtimo_ch; |
392 | |
393 | static int |
394 | do_tcpinit(void) |
395 | { |
396 | |
397 | in_pcbinit(&tcbtable, tcbhashsize, tcbhashsize); |
398 | pool_init(&tcpcb_pool, sizeof(struct tcpcb), 0, 0, 0, "tcpcbpl" , |
399 | NULL, IPL_SOFTNET); |
400 | |
401 | tcp_usrreq_init(); |
402 | |
403 | /* Initialize timer state. */ |
404 | tcp_timer_init(); |
405 | |
406 | /* Initialize the compressed state engine. */ |
407 | syn_cache_init(); |
408 | |
409 | /* Initialize the congestion control algorithms. */ |
410 | tcp_congctl_init(); |
411 | |
412 | /* Initialize the TCPCB template. */ |
413 | tcp_tcpcb_template(); |
414 | |
415 | /* Initialize reassembly queue */ |
416 | tcpipqent_init(); |
417 | |
418 | /* SACK */ |
419 | tcp_sack_init(); |
420 | |
421 | MOWNER_ATTACH(&tcp_tx_mowner); |
422 | MOWNER_ATTACH(&tcp_rx_mowner); |
423 | MOWNER_ATTACH(&tcp_reass_mowner); |
424 | MOWNER_ATTACH(&tcp_sock_mowner); |
425 | MOWNER_ATTACH(&tcp_sock_tx_mowner); |
426 | MOWNER_ATTACH(&tcp_sock_rx_mowner); |
427 | MOWNER_ATTACH(&tcp_mowner); |
428 | |
429 | tcpstat_percpu = percpu_alloc(sizeof(uint64_t) * TCP_NSTATS); |
430 | |
431 | vtw_earlyinit(); |
432 | |
433 | callout_init(&tcp_slowtimo_ch, CALLOUT_MPSAFE); |
434 | callout_reset(&tcp_slowtimo_ch, 1, tcp_slowtimo, NULL); |
435 | |
436 | return 0; |
437 | } |
438 | |
439 | void |
440 | tcp_init_common(unsigned basehlen) |
441 | { |
442 | static ONCE_DECL(dotcpinit); |
443 | unsigned hlen = basehlen + sizeof(struct tcphdr); |
444 | unsigned oldhlen; |
445 | |
446 | if (max_linkhdr + hlen > MHLEN) |
447 | panic("tcp_init" ); |
448 | while ((oldhlen = max_protohdr) < hlen) |
449 | atomic_cas_uint(&max_protohdr, oldhlen, hlen); |
450 | |
451 | RUN_ONCE(&dotcpinit, do_tcpinit); |
452 | } |
453 | |
454 | /* |
455 | * Tcp initialization |
456 | */ |
457 | void |
458 | tcp_init(void) |
459 | { |
460 | |
461 | icmp_mtudisc_callback_register(tcp_mtudisc_callback); |
462 | |
463 | tcp_init_common(sizeof(struct ip)); |
464 | } |
465 | |
466 | /* |
467 | * Create template to be used to send tcp packets on a connection. |
468 | * Call after host entry created, allocates an mbuf and fills |
469 | * in a skeletal tcp/ip header, minimizing the amount of work |
470 | * necessary when the connection is used. |
471 | */ |
472 | struct mbuf * |
473 | tcp_template(struct tcpcb *tp) |
474 | { |
475 | struct inpcb *inp = tp->t_inpcb; |
476 | #ifdef INET6 |
477 | struct in6pcb *in6p = tp->t_in6pcb; |
478 | #endif |
479 | struct tcphdr *n; |
480 | struct mbuf *m; |
481 | int hlen; |
482 | |
483 | switch (tp->t_family) { |
484 | case AF_INET: |
485 | hlen = sizeof(struct ip); |
486 | if (inp) |
487 | break; |
488 | #ifdef INET6 |
489 | if (in6p) { |
490 | /* mapped addr case */ |
491 | if (IN6_IS_ADDR_V4MAPPED(&in6p->in6p_laddr) |
492 | && IN6_IS_ADDR_V4MAPPED(&in6p->in6p_faddr)) |
493 | break; |
494 | } |
495 | #endif |
496 | return NULL; /*EINVAL*/ |
497 | #ifdef INET6 |
498 | case AF_INET6: |
499 | hlen = sizeof(struct ip6_hdr); |
500 | if (in6p) { |
501 | /* more sainty check? */ |
502 | break; |
503 | } |
504 | return NULL; /*EINVAL*/ |
505 | #endif |
506 | default: |
507 | hlen = 0; /*pacify gcc*/ |
508 | return NULL; /*EAFNOSUPPORT*/ |
509 | } |
510 | #ifdef DIAGNOSTIC |
511 | if (hlen + sizeof(struct tcphdr) > MCLBYTES) |
512 | panic("mclbytes too small for t_template" ); |
513 | #endif |
514 | m = tp->t_template; |
515 | if (m && m->m_len == hlen + sizeof(struct tcphdr)) |
516 | ; |
517 | else { |
518 | if (m) |
519 | m_freem(m); |
520 | m = tp->t_template = NULL; |
521 | MGETHDR(m, M_DONTWAIT, MT_HEADER); |
522 | if (m && hlen + sizeof(struct tcphdr) > MHLEN) { |
523 | MCLGET(m, M_DONTWAIT); |
524 | if ((m->m_flags & M_EXT) == 0) { |
525 | m_free(m); |
526 | m = NULL; |
527 | } |
528 | } |
529 | if (m == NULL) |
530 | return NULL; |
531 | MCLAIM(m, &tcp_mowner); |
532 | m->m_pkthdr.len = m->m_len = hlen + sizeof(struct tcphdr); |
533 | } |
534 | |
535 | memset(mtod(m, void *), 0, m->m_len); |
536 | |
537 | n = (struct tcphdr *)(mtod(m, char *) + hlen); |
538 | |
539 | switch (tp->t_family) { |
540 | case AF_INET: |
541 | { |
542 | struct ipovly *ipov; |
543 | mtod(m, struct ip *)->ip_v = 4; |
544 | mtod(m, struct ip *)->ip_hl = hlen >> 2; |
545 | ipov = mtod(m, struct ipovly *); |
546 | ipov->ih_pr = IPPROTO_TCP; |
547 | ipov->ih_len = htons(sizeof(struct tcphdr)); |
548 | if (inp) { |
549 | ipov->ih_src = inp->inp_laddr; |
550 | ipov->ih_dst = inp->inp_faddr; |
551 | } |
552 | #ifdef INET6 |
553 | else if (in6p) { |
554 | /* mapped addr case */ |
555 | bcopy(&in6p->in6p_laddr.s6_addr32[3], &ipov->ih_src, |
556 | sizeof(ipov->ih_src)); |
557 | bcopy(&in6p->in6p_faddr.s6_addr32[3], &ipov->ih_dst, |
558 | sizeof(ipov->ih_dst)); |
559 | } |
560 | #endif |
561 | /* |
562 | * Compute the pseudo-header portion of the checksum |
563 | * now. We incrementally add in the TCP option and |
564 | * payload lengths later, and then compute the TCP |
565 | * checksum right before the packet is sent off onto |
566 | * the wire. |
567 | */ |
568 | n->th_sum = in_cksum_phdr(ipov->ih_src.s_addr, |
569 | ipov->ih_dst.s_addr, |
570 | htons(sizeof(struct tcphdr) + IPPROTO_TCP)); |
571 | break; |
572 | } |
573 | #ifdef INET6 |
574 | case AF_INET6: |
575 | { |
576 | struct ip6_hdr *ip6; |
577 | mtod(m, struct ip *)->ip_v = 6; |
578 | ip6 = mtod(m, struct ip6_hdr *); |
579 | ip6->ip6_nxt = IPPROTO_TCP; |
580 | ip6->ip6_plen = htons(sizeof(struct tcphdr)); |
581 | ip6->ip6_src = in6p->in6p_laddr; |
582 | ip6->ip6_dst = in6p->in6p_faddr; |
583 | ip6->ip6_flow = in6p->in6p_flowinfo & IPV6_FLOWINFO_MASK; |
584 | if (ip6_auto_flowlabel) { |
585 | ip6->ip6_flow &= ~IPV6_FLOWLABEL_MASK; |
586 | ip6->ip6_flow |= |
587 | (htonl(ip6_randomflowlabel()) & IPV6_FLOWLABEL_MASK); |
588 | } |
589 | ip6->ip6_vfc &= ~IPV6_VERSION_MASK; |
590 | ip6->ip6_vfc |= IPV6_VERSION; |
591 | |
592 | /* |
593 | * Compute the pseudo-header portion of the checksum |
594 | * now. We incrementally add in the TCP option and |
595 | * payload lengths later, and then compute the TCP |
596 | * checksum right before the packet is sent off onto |
597 | * the wire. |
598 | */ |
599 | n->th_sum = in6_cksum_phdr(&in6p->in6p_laddr, |
600 | &in6p->in6p_faddr, htonl(sizeof(struct tcphdr)), |
601 | htonl(IPPROTO_TCP)); |
602 | break; |
603 | } |
604 | #endif |
605 | } |
606 | if (inp) { |
607 | n->th_sport = inp->inp_lport; |
608 | n->th_dport = inp->inp_fport; |
609 | } |
610 | #ifdef INET6 |
611 | else if (in6p) { |
612 | n->th_sport = in6p->in6p_lport; |
613 | n->th_dport = in6p->in6p_fport; |
614 | } |
615 | #endif |
616 | n->th_seq = 0; |
617 | n->th_ack = 0; |
618 | n->th_x2 = 0; |
619 | n->th_off = 5; |
620 | n->th_flags = 0; |
621 | n->th_win = 0; |
622 | n->th_urp = 0; |
623 | return (m); |
624 | } |
625 | |
626 | /* |
627 | * Send a single message to the TCP at address specified by |
628 | * the given TCP/IP header. If m == 0, then we make a copy |
629 | * of the tcpiphdr at ti and send directly to the addressed host. |
630 | * This is used to force keep alive messages out using the TCP |
631 | * template for a connection tp->t_template. If flags are given |
632 | * then we send a message back to the TCP which originated the |
633 | * segment ti, and discard the mbuf containing it and any other |
634 | * attached mbufs. |
635 | * |
636 | * In any case the ack and sequence number of the transmitted |
637 | * segment are as specified by the parameters. |
638 | */ |
639 | int |
640 | tcp_respond(struct tcpcb *tp, struct mbuf *mtemplate, struct mbuf *m, |
641 | struct tcphdr *th0, tcp_seq ack, tcp_seq seq, int flags) |
642 | { |
643 | struct route *ro; |
644 | int error, tlen, win = 0; |
645 | int hlen; |
646 | struct ip *ip; |
647 | #ifdef INET6 |
648 | struct ip6_hdr *ip6; |
649 | #endif |
650 | int family; /* family on packet, not inpcb/in6pcb! */ |
651 | struct tcphdr *th; |
652 | struct socket *so; |
653 | |
654 | if (tp != NULL && (flags & TH_RST) == 0) { |
655 | #ifdef DIAGNOSTIC |
656 | if (tp->t_inpcb && tp->t_in6pcb) |
657 | panic("tcp_respond: both t_inpcb and t_in6pcb are set" ); |
658 | #endif |
659 | #ifdef INET |
660 | if (tp->t_inpcb) |
661 | win = sbspace(&tp->t_inpcb->inp_socket->so_rcv); |
662 | #endif |
663 | #ifdef INET6 |
664 | if (tp->t_in6pcb) |
665 | win = sbspace(&tp->t_in6pcb->in6p_socket->so_rcv); |
666 | #endif |
667 | } |
668 | |
669 | th = NULL; /* Quell uninitialized warning */ |
670 | ip = NULL; |
671 | #ifdef INET6 |
672 | ip6 = NULL; |
673 | #endif |
674 | if (m == 0) { |
675 | if (!mtemplate) |
676 | return EINVAL; |
677 | |
678 | /* get family information from template */ |
679 | switch (mtod(mtemplate, struct ip *)->ip_v) { |
680 | case 4: |
681 | family = AF_INET; |
682 | hlen = sizeof(struct ip); |
683 | break; |
684 | #ifdef INET6 |
685 | case 6: |
686 | family = AF_INET6; |
687 | hlen = sizeof(struct ip6_hdr); |
688 | break; |
689 | #endif |
690 | default: |
691 | return EAFNOSUPPORT; |
692 | } |
693 | |
694 | MGETHDR(m, M_DONTWAIT, MT_HEADER); |
695 | if (m) { |
696 | MCLAIM(m, &tcp_tx_mowner); |
697 | MCLGET(m, M_DONTWAIT); |
698 | if ((m->m_flags & M_EXT) == 0) { |
699 | m_free(m); |
700 | m = NULL; |
701 | } |
702 | } |
703 | if (m == NULL) |
704 | return (ENOBUFS); |
705 | |
706 | if (tcp_compat_42) |
707 | tlen = 1; |
708 | else |
709 | tlen = 0; |
710 | |
711 | m->m_data += max_linkhdr; |
712 | bcopy(mtod(mtemplate, void *), mtod(m, void *), |
713 | mtemplate->m_len); |
714 | switch (family) { |
715 | case AF_INET: |
716 | ip = mtod(m, struct ip *); |
717 | th = (struct tcphdr *)(ip + 1); |
718 | break; |
719 | #ifdef INET6 |
720 | case AF_INET6: |
721 | ip6 = mtod(m, struct ip6_hdr *); |
722 | th = (struct tcphdr *)(ip6 + 1); |
723 | break; |
724 | #endif |
725 | #if 0 |
726 | default: |
727 | /* noone will visit here */ |
728 | m_freem(m); |
729 | return EAFNOSUPPORT; |
730 | #endif |
731 | } |
732 | flags = TH_ACK; |
733 | } else { |
734 | |
735 | if ((m->m_flags & M_PKTHDR) == 0) { |
736 | #if 0 |
737 | printf("non PKTHDR to tcp_respond\n" ); |
738 | #endif |
739 | m_freem(m); |
740 | return EINVAL; |
741 | } |
742 | #ifdef DIAGNOSTIC |
743 | if (!th0) |
744 | panic("th0 == NULL in tcp_respond" ); |
745 | #endif |
746 | |
747 | /* get family information from m */ |
748 | switch (mtod(m, struct ip *)->ip_v) { |
749 | case 4: |
750 | family = AF_INET; |
751 | hlen = sizeof(struct ip); |
752 | ip = mtod(m, struct ip *); |
753 | break; |
754 | #ifdef INET6 |
755 | case 6: |
756 | family = AF_INET6; |
757 | hlen = sizeof(struct ip6_hdr); |
758 | ip6 = mtod(m, struct ip6_hdr *); |
759 | break; |
760 | #endif |
761 | default: |
762 | m_freem(m); |
763 | return EAFNOSUPPORT; |
764 | } |
765 | /* clear h/w csum flags inherited from rx packet */ |
766 | m->m_pkthdr.csum_flags = 0; |
767 | |
768 | if ((flags & TH_SYN) == 0 || sizeof(*th0) > (th0->th_off << 2)) |
769 | tlen = sizeof(*th0); |
770 | else |
771 | tlen = th0->th_off << 2; |
772 | |
773 | if (m->m_len > hlen + tlen && (m->m_flags & M_EXT) == 0 && |
774 | mtod(m, char *) + hlen == (char *)th0) { |
775 | m->m_len = hlen + tlen; |
776 | m_freem(m->m_next); |
777 | m->m_next = NULL; |
778 | } else { |
779 | struct mbuf *n; |
780 | |
781 | #ifdef DIAGNOSTIC |
782 | if (max_linkhdr + hlen + tlen > MCLBYTES) { |
783 | m_freem(m); |
784 | return EMSGSIZE; |
785 | } |
786 | #endif |
787 | MGETHDR(n, M_DONTWAIT, MT_HEADER); |
788 | if (n && max_linkhdr + hlen + tlen > MHLEN) { |
789 | MCLGET(n, M_DONTWAIT); |
790 | if ((n->m_flags & M_EXT) == 0) { |
791 | m_freem(n); |
792 | n = NULL; |
793 | } |
794 | } |
795 | if (!n) { |
796 | m_freem(m); |
797 | return ENOBUFS; |
798 | } |
799 | |
800 | MCLAIM(n, &tcp_tx_mowner); |
801 | n->m_data += max_linkhdr; |
802 | n->m_len = hlen + tlen; |
803 | m_copyback(n, 0, hlen, mtod(m, void *)); |
804 | m_copyback(n, hlen, tlen, (void *)th0); |
805 | |
806 | m_freem(m); |
807 | m = n; |
808 | n = NULL; |
809 | } |
810 | |
811 | #define xchg(a,b,type) { type t; t=a; a=b; b=t; } |
812 | switch (family) { |
813 | case AF_INET: |
814 | ip = mtod(m, struct ip *); |
815 | th = (struct tcphdr *)(ip + 1); |
816 | ip->ip_p = IPPROTO_TCP; |
817 | xchg(ip->ip_dst, ip->ip_src, struct in_addr); |
818 | ip->ip_p = IPPROTO_TCP; |
819 | break; |
820 | #ifdef INET6 |
821 | case AF_INET6: |
822 | ip6 = mtod(m, struct ip6_hdr *); |
823 | th = (struct tcphdr *)(ip6 + 1); |
824 | ip6->ip6_nxt = IPPROTO_TCP; |
825 | xchg(ip6->ip6_dst, ip6->ip6_src, struct in6_addr); |
826 | ip6->ip6_nxt = IPPROTO_TCP; |
827 | break; |
828 | #endif |
829 | #if 0 |
830 | default: |
831 | /* noone will visit here */ |
832 | m_freem(m); |
833 | return EAFNOSUPPORT; |
834 | #endif |
835 | } |
836 | xchg(th->th_dport, th->th_sport, u_int16_t); |
837 | #undef xchg |
838 | tlen = 0; /*be friendly with the following code*/ |
839 | } |
840 | th->th_seq = htonl(seq); |
841 | th->th_ack = htonl(ack); |
842 | th->th_x2 = 0; |
843 | if ((flags & TH_SYN) == 0) { |
844 | if (tp) |
845 | win >>= tp->rcv_scale; |
846 | if (win > TCP_MAXWIN) |
847 | win = TCP_MAXWIN; |
848 | th->th_win = htons((u_int16_t)win); |
849 | th->th_off = sizeof (struct tcphdr) >> 2; |
850 | tlen += sizeof(*th); |
851 | } else |
852 | tlen += th->th_off << 2; |
853 | m->m_len = hlen + tlen; |
854 | m->m_pkthdr.len = hlen + tlen; |
855 | m_reset_rcvif(m); |
856 | th->th_flags = flags; |
857 | th->th_urp = 0; |
858 | |
859 | switch (family) { |
860 | #ifdef INET |
861 | case AF_INET: |
862 | { |
863 | struct ipovly *ipov = (struct ipovly *)ip; |
864 | memset(ipov->ih_x1, 0, sizeof ipov->ih_x1); |
865 | ipov->ih_len = htons((u_int16_t)tlen); |
866 | |
867 | th->th_sum = 0; |
868 | th->th_sum = in_cksum(m, hlen + tlen); |
869 | ip->ip_len = htons(hlen + tlen); |
870 | ip->ip_ttl = ip_defttl; |
871 | break; |
872 | } |
873 | #endif |
874 | #ifdef INET6 |
875 | case AF_INET6: |
876 | { |
877 | th->th_sum = 0; |
878 | th->th_sum = in6_cksum(m, IPPROTO_TCP, sizeof(struct ip6_hdr), |
879 | tlen); |
880 | ip6->ip6_plen = htons(tlen); |
881 | if (tp && tp->t_in6pcb) |
882 | ip6->ip6_hlim = in6_selecthlim_rt(tp->t_in6pcb); |
883 | else |
884 | ip6->ip6_hlim = ip6_defhlim; |
885 | ip6->ip6_flow &= ~IPV6_FLOWINFO_MASK; |
886 | if (ip6_auto_flowlabel) { |
887 | ip6->ip6_flow |= |
888 | (htonl(ip6_randomflowlabel()) & IPV6_FLOWLABEL_MASK); |
889 | } |
890 | break; |
891 | } |
892 | #endif |
893 | } |
894 | |
895 | if (tp && tp->t_inpcb) |
896 | so = tp->t_inpcb->inp_socket; |
897 | #ifdef INET6 |
898 | else if (tp && tp->t_in6pcb) |
899 | so = tp->t_in6pcb->in6p_socket; |
900 | #endif |
901 | else |
902 | so = NULL; |
903 | |
904 | if (tp != NULL && tp->t_inpcb != NULL) { |
905 | ro = &tp->t_inpcb->inp_route; |
906 | #ifdef DIAGNOSTIC |
907 | if (family != AF_INET) |
908 | panic("tcp_respond: address family mismatch" ); |
909 | if (!in_hosteq(ip->ip_dst, tp->t_inpcb->inp_faddr)) { |
910 | panic("tcp_respond: ip_dst %x != inp_faddr %x" , |
911 | ntohl(ip->ip_dst.s_addr), |
912 | ntohl(tp->t_inpcb->inp_faddr.s_addr)); |
913 | } |
914 | #endif |
915 | } |
916 | #ifdef INET6 |
917 | else if (tp != NULL && tp->t_in6pcb != NULL) { |
918 | ro = (struct route *)&tp->t_in6pcb->in6p_route; |
919 | #ifdef DIAGNOSTIC |
920 | if (family == AF_INET) { |
921 | if (!IN6_IS_ADDR_V4MAPPED(&tp->t_in6pcb->in6p_faddr)) |
922 | panic("tcp_respond: not mapped addr" ); |
923 | if (memcmp(&ip->ip_dst, |
924 | &tp->t_in6pcb->in6p_faddr.s6_addr32[3], |
925 | sizeof(ip->ip_dst)) != 0) { |
926 | panic("tcp_respond: ip_dst != in6p_faddr" ); |
927 | } |
928 | } else if (family == AF_INET6) { |
929 | if (!IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, |
930 | &tp->t_in6pcb->in6p_faddr)) |
931 | panic("tcp_respond: ip6_dst != in6p_faddr" ); |
932 | } else |
933 | panic("tcp_respond: address family mismatch" ); |
934 | #endif |
935 | } |
936 | #endif |
937 | else |
938 | ro = NULL; |
939 | |
940 | switch (family) { |
941 | #ifdef INET |
942 | case AF_INET: |
943 | error = ip_output(m, NULL, ro, |
944 | (tp && tp->t_mtudisc ? IP_MTUDISC : 0), NULL, so); |
945 | break; |
946 | #endif |
947 | #ifdef INET6 |
948 | case AF_INET6: |
949 | error = ip6_output(m, NULL, ro, 0, NULL, so, NULL); |
950 | break; |
951 | #endif |
952 | default: |
953 | error = EAFNOSUPPORT; |
954 | break; |
955 | } |
956 | |
957 | return (error); |
958 | } |
959 | |
960 | /* |
961 | * Template TCPCB. Rather than zeroing a new TCPCB and initializing |
962 | * a bunch of members individually, we maintain this template for the |
963 | * static and mostly-static components of the TCPCB, and copy it into |
964 | * the new TCPCB instead. |
965 | */ |
966 | static struct tcpcb tcpcb_template = { |
967 | .t_srtt = TCPTV_SRTTBASE, |
968 | .t_rttmin = TCPTV_MIN, |
969 | |
970 | .snd_cwnd = TCP_MAXWIN << TCP_MAX_WINSHIFT, |
971 | .snd_ssthresh = TCP_MAXWIN << TCP_MAX_WINSHIFT, |
972 | .snd_numholes = 0, |
973 | .snd_cubic_wmax = 0, |
974 | .snd_cubic_wmax_last = 0, |
975 | .snd_cubic_ctime = 0, |
976 | |
977 | .t_partialacks = -1, |
978 | .t_bytes_acked = 0, |
979 | .t_sndrexmitpack = 0, |
980 | .t_rcvoopack = 0, |
981 | .t_sndzerowin = 0, |
982 | }; |
983 | |
984 | /* |
985 | * Updates the TCPCB template whenever a parameter that would affect |
986 | * the template is changed. |
987 | */ |
988 | void |
989 | tcp_tcpcb_template(void) |
990 | { |
991 | struct tcpcb *tp = &tcpcb_template; |
992 | int flags; |
993 | |
994 | tp->t_peermss = tcp_mssdflt; |
995 | tp->t_ourmss = tcp_mssdflt; |
996 | tp->t_segsz = tcp_mssdflt; |
997 | |
998 | flags = 0; |
999 | if (tcp_do_rfc1323 && tcp_do_win_scale) |
1000 | flags |= TF_REQ_SCALE; |
1001 | if (tcp_do_rfc1323 && tcp_do_timestamps) |
1002 | flags |= TF_REQ_TSTMP; |
1003 | tp->t_flags = flags; |
1004 | |
1005 | /* |
1006 | * Init srtt to TCPTV_SRTTBASE (0), so we can tell that we have no |
1007 | * rtt estimate. Set rttvar so that srtt + 2 * rttvar gives |
1008 | * reasonable initial retransmit time. |
1009 | */ |
1010 | tp->t_rttvar = tcp_rttdflt * PR_SLOWHZ << (TCP_RTTVAR_SHIFT + 2 - 1); |
1011 | TCPT_RANGESET(tp->t_rxtcur, TCP_REXMTVAL(tp), |
1012 | TCPTV_MIN, TCPTV_REXMTMAX); |
1013 | |
1014 | /* Keep Alive */ |
1015 | tp->t_keepinit = tcp_keepinit; |
1016 | tp->t_keepidle = tcp_keepidle; |
1017 | tp->t_keepintvl = tcp_keepintvl; |
1018 | tp->t_keepcnt = tcp_keepcnt; |
1019 | tp->t_maxidle = tp->t_keepcnt * tp->t_keepintvl; |
1020 | |
1021 | /* MSL */ |
1022 | tp->t_msl = TCPTV_MSL; |
1023 | } |
1024 | |
1025 | /* |
1026 | * Create a new TCP control block, making an |
1027 | * empty reassembly queue and hooking it to the argument |
1028 | * protocol control block. |
1029 | */ |
1030 | /* family selects inpcb, or in6pcb */ |
1031 | struct tcpcb * |
1032 | tcp_newtcpcb(int family, void *aux) |
1033 | { |
1034 | struct tcpcb *tp; |
1035 | int i; |
1036 | |
1037 | /* XXX Consider using a pool_cache for speed. */ |
1038 | tp = pool_get(&tcpcb_pool, PR_NOWAIT); /* splsoftnet via tcp_usrreq */ |
1039 | if (tp == NULL) |
1040 | return (NULL); |
1041 | memcpy(tp, &tcpcb_template, sizeof(*tp)); |
1042 | TAILQ_INIT(&tp->segq); |
1043 | TAILQ_INIT(&tp->timeq); |
1044 | tp->t_family = family; /* may be overridden later on */ |
1045 | TAILQ_INIT(&tp->snd_holes); |
1046 | LIST_INIT(&tp->t_sc); /* XXX can template this */ |
1047 | |
1048 | /* Don't sweat this loop; hopefully the compiler will unroll it. */ |
1049 | for (i = 0; i < TCPT_NTIMERS; i++) { |
1050 | callout_init(&tp->t_timer[i], CALLOUT_MPSAFE); |
1051 | TCP_TIMER_INIT(tp, i); |
1052 | } |
1053 | callout_init(&tp->t_delack_ch, CALLOUT_MPSAFE); |
1054 | |
1055 | switch (family) { |
1056 | case AF_INET: |
1057 | { |
1058 | struct inpcb *inp = (struct inpcb *)aux; |
1059 | |
1060 | inp->inp_ip.ip_ttl = ip_defttl; |
1061 | inp->inp_ppcb = (void *)tp; |
1062 | |
1063 | tp->t_inpcb = inp; |
1064 | tp->t_mtudisc = ip_mtudisc; |
1065 | break; |
1066 | } |
1067 | #ifdef INET6 |
1068 | case AF_INET6: |
1069 | { |
1070 | struct in6pcb *in6p = (struct in6pcb *)aux; |
1071 | |
1072 | in6p->in6p_ip6.ip6_hlim = in6_selecthlim_rt(in6p); |
1073 | in6p->in6p_ppcb = (void *)tp; |
1074 | |
1075 | tp->t_in6pcb = in6p; |
1076 | /* for IPv6, always try to run path MTU discovery */ |
1077 | tp->t_mtudisc = 1; |
1078 | break; |
1079 | } |
1080 | #endif /* INET6 */ |
1081 | default: |
1082 | for (i = 0; i < TCPT_NTIMERS; i++) |
1083 | callout_destroy(&tp->t_timer[i]); |
1084 | callout_destroy(&tp->t_delack_ch); |
1085 | pool_put(&tcpcb_pool, tp); /* splsoftnet via tcp_usrreq */ |
1086 | return (NULL); |
1087 | } |
1088 | |
1089 | /* |
1090 | * Initialize our timebase. When we send timestamps, we take |
1091 | * the delta from tcp_now -- this means each connection always |
1092 | * gets a timebase of 1, which makes it, among other things, |
1093 | * more difficult to determine how long a system has been up, |
1094 | * and thus how many TCP sequence increments have occurred. |
1095 | * |
1096 | * We start with 1, because 0 doesn't work with linux, which |
1097 | * considers timestamp 0 in a SYN packet as a bug and disables |
1098 | * timestamps. |
1099 | */ |
1100 | tp->ts_timebase = tcp_now - 1; |
1101 | |
1102 | tcp_congctl_select(tp, tcp_congctl_global_name); |
1103 | |
1104 | return (tp); |
1105 | } |
1106 | |
1107 | /* |
1108 | * Drop a TCP connection, reporting |
1109 | * the specified error. If connection is synchronized, |
1110 | * then send a RST to peer. |
1111 | */ |
1112 | struct tcpcb * |
1113 | tcp_drop(struct tcpcb *tp, int errno) |
1114 | { |
1115 | struct socket *so = NULL; |
1116 | |
1117 | #ifdef DIAGNOSTIC |
1118 | if (tp->t_inpcb && tp->t_in6pcb) |
1119 | panic("tcp_drop: both t_inpcb and t_in6pcb are set" ); |
1120 | #endif |
1121 | #ifdef INET |
1122 | if (tp->t_inpcb) |
1123 | so = tp->t_inpcb->inp_socket; |
1124 | #endif |
1125 | #ifdef INET6 |
1126 | if (tp->t_in6pcb) |
1127 | so = tp->t_in6pcb->in6p_socket; |
1128 | #endif |
1129 | if (!so) |
1130 | return NULL; |
1131 | |
1132 | if (TCPS_HAVERCVDSYN(tp->t_state)) { |
1133 | tp->t_state = TCPS_CLOSED; |
1134 | (void) tcp_output(tp); |
1135 | TCP_STATINC(TCP_STAT_DROPS); |
1136 | } else |
1137 | TCP_STATINC(TCP_STAT_CONNDROPS); |
1138 | if (errno == ETIMEDOUT && tp->t_softerror) |
1139 | errno = tp->t_softerror; |
1140 | so->so_error = errno; |
1141 | return (tcp_close(tp)); |
1142 | } |
1143 | |
1144 | /* |
1145 | * Close a TCP control block: |
1146 | * discard all space held by the tcp |
1147 | * discard internet protocol block |
1148 | * wake up any sleepers |
1149 | */ |
1150 | struct tcpcb * |
1151 | tcp_close(struct tcpcb *tp) |
1152 | { |
1153 | struct inpcb *inp; |
1154 | #ifdef INET6 |
1155 | struct in6pcb *in6p; |
1156 | #endif |
1157 | struct socket *so; |
1158 | #ifdef RTV_RTT |
1159 | struct rtentry *rt; |
1160 | #endif |
1161 | struct route *ro; |
1162 | int j; |
1163 | |
1164 | inp = tp->t_inpcb; |
1165 | #ifdef INET6 |
1166 | in6p = tp->t_in6pcb; |
1167 | #endif |
1168 | so = NULL; |
1169 | ro = NULL; |
1170 | if (inp) { |
1171 | so = inp->inp_socket; |
1172 | ro = &inp->inp_route; |
1173 | } |
1174 | #ifdef INET6 |
1175 | else if (in6p) { |
1176 | so = in6p->in6p_socket; |
1177 | ro = (struct route *)&in6p->in6p_route; |
1178 | } |
1179 | #endif |
1180 | |
1181 | #ifdef RTV_RTT |
1182 | /* |
1183 | * If we sent enough data to get some meaningful characteristics, |
1184 | * save them in the routing entry. 'Enough' is arbitrarily |
1185 | * defined as the sendpipesize (default 4K) * 16. This would |
1186 | * give us 16 rtt samples assuming we only get one sample per |
1187 | * window (the usual case on a long haul net). 16 samples is |
1188 | * enough for the srtt filter to converge to within 5% of the correct |
1189 | * value; fewer samples and we could save a very bogus rtt. |
1190 | * |
1191 | * Don't update the default route's characteristics and don't |
1192 | * update anything that the user "locked". |
1193 | */ |
1194 | if (SEQ_LT(tp->iss + so->so_snd.sb_hiwat * 16, tp->snd_max) && |
1195 | ro && (rt = rtcache_validate(ro)) != NULL && |
1196 | !in_nullhost(satocsin(rt_getkey(rt))->sin_addr)) { |
1197 | u_long i = 0; |
1198 | |
1199 | if ((rt->rt_rmx.rmx_locks & RTV_RTT) == 0) { |
1200 | i = tp->t_srtt * |
1201 | ((RTM_RTTUNIT / PR_SLOWHZ) >> (TCP_RTT_SHIFT + 2)); |
1202 | if (rt->rt_rmx.rmx_rtt && i) |
1203 | /* |
1204 | * filter this update to half the old & half |
1205 | * the new values, converting scale. |
1206 | * See route.h and tcp_var.h for a |
1207 | * description of the scaling constants. |
1208 | */ |
1209 | rt->rt_rmx.rmx_rtt = |
1210 | (rt->rt_rmx.rmx_rtt + i) / 2; |
1211 | else |
1212 | rt->rt_rmx.rmx_rtt = i; |
1213 | } |
1214 | if ((rt->rt_rmx.rmx_locks & RTV_RTTVAR) == 0) { |
1215 | i = tp->t_rttvar * |
1216 | ((RTM_RTTUNIT / PR_SLOWHZ) >> (TCP_RTTVAR_SHIFT + 2)); |
1217 | if (rt->rt_rmx.rmx_rttvar && i) |
1218 | rt->rt_rmx.rmx_rttvar = |
1219 | (rt->rt_rmx.rmx_rttvar + i) / 2; |
1220 | else |
1221 | rt->rt_rmx.rmx_rttvar = i; |
1222 | } |
1223 | /* |
1224 | * update the pipelimit (ssthresh) if it has been updated |
1225 | * already or if a pipesize was specified & the threshhold |
1226 | * got below half the pipesize. I.e., wait for bad news |
1227 | * before we start updating, then update on both good |
1228 | * and bad news. |
1229 | */ |
1230 | if (((rt->rt_rmx.rmx_locks & RTV_SSTHRESH) == 0 && |
1231 | (i = tp->snd_ssthresh) && rt->rt_rmx.rmx_ssthresh) || |
1232 | i < (rt->rt_rmx.rmx_sendpipe / 2)) { |
1233 | /* |
1234 | * convert the limit from user data bytes to |
1235 | * packets then to packet data bytes. |
1236 | */ |
1237 | i = (i + tp->t_segsz / 2) / tp->t_segsz; |
1238 | if (i < 2) |
1239 | i = 2; |
1240 | i *= (u_long)(tp->t_segsz + sizeof (struct tcpiphdr)); |
1241 | if (rt->rt_rmx.rmx_ssthresh) |
1242 | rt->rt_rmx.rmx_ssthresh = |
1243 | (rt->rt_rmx.rmx_ssthresh + i) / 2; |
1244 | else |
1245 | rt->rt_rmx.rmx_ssthresh = i; |
1246 | } |
1247 | } |
1248 | #endif /* RTV_RTT */ |
1249 | /* free the reassembly queue, if any */ |
1250 | TCP_REASS_LOCK(tp); |
1251 | (void) tcp_freeq(tp); |
1252 | TCP_REASS_UNLOCK(tp); |
1253 | |
1254 | /* free the SACK holes list. */ |
1255 | tcp_free_sackholes(tp); |
1256 | tcp_congctl_release(tp); |
1257 | syn_cache_cleanup(tp); |
1258 | |
1259 | if (tp->t_template) { |
1260 | m_free(tp->t_template); |
1261 | tp->t_template = NULL; |
1262 | } |
1263 | |
1264 | /* |
1265 | * Detaching the pcb will unlock the socket/tcpcb, and stopping |
1266 | * the timers can also drop the lock. We need to prevent access |
1267 | * to the tcpcb as it's half torn down. Flag the pcb as dead |
1268 | * (prevents access by timers) and only then detach it. |
1269 | */ |
1270 | tp->t_flags |= TF_DEAD; |
1271 | if (inp) { |
1272 | inp->inp_ppcb = 0; |
1273 | soisdisconnected(so); |
1274 | in_pcbdetach(inp); |
1275 | } |
1276 | #ifdef INET6 |
1277 | else if (in6p) { |
1278 | in6p->in6p_ppcb = 0; |
1279 | soisdisconnected(so); |
1280 | in6_pcbdetach(in6p); |
1281 | } |
1282 | #endif |
1283 | /* |
1284 | * pcb is no longer visble elsewhere, so we can safely release |
1285 | * the lock in callout_halt() if needed. |
1286 | */ |
1287 | TCP_STATINC(TCP_STAT_CLOSED); |
1288 | for (j = 0; j < TCPT_NTIMERS; j++) { |
1289 | callout_halt(&tp->t_timer[j], softnet_lock); |
1290 | callout_destroy(&tp->t_timer[j]); |
1291 | } |
1292 | callout_halt(&tp->t_delack_ch, softnet_lock); |
1293 | callout_destroy(&tp->t_delack_ch); |
1294 | pool_put(&tcpcb_pool, tp); |
1295 | |
1296 | return NULL; |
1297 | } |
1298 | |
1299 | int |
1300 | tcp_freeq(struct tcpcb *tp) |
1301 | { |
1302 | struct ipqent *qe; |
1303 | int rv = 0; |
1304 | #ifdef TCPREASS_DEBUG |
1305 | int i = 0; |
1306 | #endif |
1307 | |
1308 | TCP_REASS_LOCK_CHECK(tp); |
1309 | |
1310 | while ((qe = TAILQ_FIRST(&tp->segq)) != NULL) { |
1311 | #ifdef TCPREASS_DEBUG |
1312 | printf("tcp_freeq[%p,%d]: %u:%u(%u) 0x%02x\n" , |
1313 | tp, i++, qe->ipqe_seq, qe->ipqe_seq + qe->ipqe_len, |
1314 | qe->ipqe_len, qe->ipqe_flags & (TH_SYN|TH_FIN|TH_RST)); |
1315 | #endif |
1316 | TAILQ_REMOVE(&tp->segq, qe, ipqe_q); |
1317 | TAILQ_REMOVE(&tp->timeq, qe, ipqe_timeq); |
1318 | m_freem(qe->ipqe_m); |
1319 | tcpipqent_free(qe); |
1320 | rv = 1; |
1321 | } |
1322 | tp->t_segqlen = 0; |
1323 | KASSERT(TAILQ_EMPTY(&tp->timeq)); |
1324 | return (rv); |
1325 | } |
1326 | |
1327 | void |
1328 | tcp_fasttimo(void) |
1329 | { |
1330 | if (tcp_drainwanted) { |
1331 | tcp_drain(); |
1332 | tcp_drainwanted = 0; |
1333 | } |
1334 | } |
1335 | |
1336 | void |
1337 | tcp_drainstub(void) |
1338 | { |
1339 | tcp_drainwanted = 1; |
1340 | } |
1341 | |
1342 | /* |
1343 | * Protocol drain routine. Called when memory is in short supply. |
1344 | * Called from pr_fasttimo thus a callout context. |
1345 | */ |
1346 | void |
1347 | tcp_drain(void) |
1348 | { |
1349 | struct inpcb_hdr *inph; |
1350 | struct tcpcb *tp; |
1351 | |
1352 | mutex_enter(softnet_lock); |
1353 | KERNEL_LOCK(1, NULL); |
1354 | |
1355 | /* |
1356 | * Free the sequence queue of all TCP connections. |
1357 | */ |
1358 | TAILQ_FOREACH(inph, &tcbtable.inpt_queue, inph_queue) { |
1359 | switch (inph->inph_af) { |
1360 | case AF_INET: |
1361 | tp = intotcpcb((struct inpcb *)inph); |
1362 | break; |
1363 | #ifdef INET6 |
1364 | case AF_INET6: |
1365 | tp = in6totcpcb((struct in6pcb *)inph); |
1366 | break; |
1367 | #endif |
1368 | default: |
1369 | tp = NULL; |
1370 | break; |
1371 | } |
1372 | if (tp != NULL) { |
1373 | /* |
1374 | * We may be called from a device's interrupt |
1375 | * context. If the tcpcb is already busy, |
1376 | * just bail out now. |
1377 | */ |
1378 | if (tcp_reass_lock_try(tp) == 0) |
1379 | continue; |
1380 | if (tcp_freeq(tp)) |
1381 | TCP_STATINC(TCP_STAT_CONNSDRAINED); |
1382 | TCP_REASS_UNLOCK(tp); |
1383 | } |
1384 | } |
1385 | |
1386 | KERNEL_UNLOCK_ONE(NULL); |
1387 | mutex_exit(softnet_lock); |
1388 | } |
1389 | |
1390 | /* |
1391 | * Notify a tcp user of an asynchronous error; |
1392 | * store error as soft error, but wake up user |
1393 | * (for now, won't do anything until can select for soft error). |
1394 | */ |
1395 | void |
1396 | tcp_notify(struct inpcb *inp, int error) |
1397 | { |
1398 | struct tcpcb *tp = (struct tcpcb *)inp->inp_ppcb; |
1399 | struct socket *so = inp->inp_socket; |
1400 | |
1401 | /* |
1402 | * Ignore some errors if we are hooked up. |
1403 | * If connection hasn't completed, has retransmitted several times, |
1404 | * and receives a second error, give up now. This is better |
1405 | * than waiting a long time to establish a connection that |
1406 | * can never complete. |
1407 | */ |
1408 | if (tp->t_state == TCPS_ESTABLISHED && |
1409 | (error == EHOSTUNREACH || error == ENETUNREACH || |
1410 | error == EHOSTDOWN)) { |
1411 | return; |
1412 | } else if (TCPS_HAVEESTABLISHED(tp->t_state) == 0 && |
1413 | tp->t_rxtshift > 3 && tp->t_softerror) |
1414 | so->so_error = error; |
1415 | else |
1416 | tp->t_softerror = error; |
1417 | cv_broadcast(&so->so_cv); |
1418 | sorwakeup(so); |
1419 | sowwakeup(so); |
1420 | } |
1421 | |
1422 | #ifdef INET6 |
1423 | void |
1424 | tcp6_notify(struct in6pcb *in6p, int error) |
1425 | { |
1426 | struct tcpcb *tp = (struct tcpcb *)in6p->in6p_ppcb; |
1427 | struct socket *so = in6p->in6p_socket; |
1428 | |
1429 | /* |
1430 | * Ignore some errors if we are hooked up. |
1431 | * If connection hasn't completed, has retransmitted several times, |
1432 | * and receives a second error, give up now. This is better |
1433 | * than waiting a long time to establish a connection that |
1434 | * can never complete. |
1435 | */ |
1436 | if (tp->t_state == TCPS_ESTABLISHED && |
1437 | (error == EHOSTUNREACH || error == ENETUNREACH || |
1438 | error == EHOSTDOWN)) { |
1439 | return; |
1440 | } else if (TCPS_HAVEESTABLISHED(tp->t_state) == 0 && |
1441 | tp->t_rxtshift > 3 && tp->t_softerror) |
1442 | so->so_error = error; |
1443 | else |
1444 | tp->t_softerror = error; |
1445 | cv_broadcast(&so->so_cv); |
1446 | sorwakeup(so); |
1447 | sowwakeup(so); |
1448 | } |
1449 | #endif |
1450 | |
1451 | #ifdef INET6 |
1452 | void * |
1453 | tcp6_ctlinput(int cmd, const struct sockaddr *sa, void *d) |
1454 | { |
1455 | struct tcphdr th; |
1456 | void (*notify)(struct in6pcb *, int) = tcp6_notify; |
1457 | int nmatch; |
1458 | struct ip6_hdr *ip6; |
1459 | const struct sockaddr_in6 *sa6_src = NULL; |
1460 | const struct sockaddr_in6 *sa6 = (const struct sockaddr_in6 *)sa; |
1461 | struct mbuf *m; |
1462 | int off; |
1463 | |
1464 | if (sa->sa_family != AF_INET6 || |
1465 | sa->sa_len != sizeof(struct sockaddr_in6)) |
1466 | return NULL; |
1467 | if ((unsigned)cmd >= PRC_NCMDS) |
1468 | return NULL; |
1469 | else if (cmd == PRC_QUENCH) { |
1470 | /* |
1471 | * Don't honor ICMP Source Quench messages meant for |
1472 | * TCP connections. |
1473 | */ |
1474 | return NULL; |
1475 | } else if (PRC_IS_REDIRECT(cmd)) |
1476 | notify = in6_rtchange, d = NULL; |
1477 | else if (cmd == PRC_MSGSIZE) |
1478 | ; /* special code is present, see below */ |
1479 | else if (cmd == PRC_HOSTDEAD) |
1480 | d = NULL; |
1481 | else if (inet6ctlerrmap[cmd] == 0) |
1482 | return NULL; |
1483 | |
1484 | /* if the parameter is from icmp6, decode it. */ |
1485 | if (d != NULL) { |
1486 | struct ip6ctlparam *ip6cp = (struct ip6ctlparam *)d; |
1487 | m = ip6cp->ip6c_m; |
1488 | ip6 = ip6cp->ip6c_ip6; |
1489 | off = ip6cp->ip6c_off; |
1490 | sa6_src = ip6cp->ip6c_src; |
1491 | } else { |
1492 | m = NULL; |
1493 | ip6 = NULL; |
1494 | sa6_src = &sa6_any; |
1495 | off = 0; |
1496 | } |
1497 | |
1498 | if (ip6) { |
1499 | /* |
1500 | * XXX: We assume that when ip6 is non NULL, |
1501 | * M and OFF are valid. |
1502 | */ |
1503 | |
1504 | /* check if we can safely examine src and dst ports */ |
1505 | if (m->m_pkthdr.len < off + sizeof(th)) { |
1506 | if (cmd == PRC_MSGSIZE) |
1507 | icmp6_mtudisc_update((struct ip6ctlparam *)d, 0); |
1508 | return NULL; |
1509 | } |
1510 | |
1511 | memset(&th, 0, sizeof(th)); |
1512 | m_copydata(m, off, sizeof(th), (void *)&th); |
1513 | |
1514 | if (cmd == PRC_MSGSIZE) { |
1515 | int valid = 0; |
1516 | |
1517 | /* |
1518 | * Check to see if we have a valid TCP connection |
1519 | * corresponding to the address in the ICMPv6 message |
1520 | * payload. |
1521 | */ |
1522 | if (in6_pcblookup_connect(&tcbtable, &sa6->sin6_addr, |
1523 | th.th_dport, |
1524 | (const struct in6_addr *)&sa6_src->sin6_addr, |
1525 | th.th_sport, 0, 0)) |
1526 | valid++; |
1527 | |
1528 | /* |
1529 | * Depending on the value of "valid" and routing table |
1530 | * size (mtudisc_{hi,lo}wat), we will: |
1531 | * - recalcurate the new MTU and create the |
1532 | * corresponding routing entry, or |
1533 | * - ignore the MTU change notification. |
1534 | */ |
1535 | icmp6_mtudisc_update((struct ip6ctlparam *)d, valid); |
1536 | |
1537 | /* |
1538 | * no need to call in6_pcbnotify, it should have been |
1539 | * called via callback if necessary |
1540 | */ |
1541 | return NULL; |
1542 | } |
1543 | |
1544 | nmatch = in6_pcbnotify(&tcbtable, sa, th.th_dport, |
1545 | (const struct sockaddr *)sa6_src, th.th_sport, cmd, NULL, notify); |
1546 | if (nmatch == 0 && syn_cache_count && |
1547 | (inet6ctlerrmap[cmd] == EHOSTUNREACH || |
1548 | inet6ctlerrmap[cmd] == ENETUNREACH || |
1549 | inet6ctlerrmap[cmd] == EHOSTDOWN)) |
1550 | syn_cache_unreach((const struct sockaddr *)sa6_src, |
1551 | sa, &th); |
1552 | } else { |
1553 | (void) in6_pcbnotify(&tcbtable, sa, 0, |
1554 | (const struct sockaddr *)sa6_src, 0, cmd, NULL, notify); |
1555 | } |
1556 | |
1557 | return NULL; |
1558 | } |
1559 | #endif |
1560 | |
1561 | #ifdef INET |
1562 | /* assumes that ip header and tcp header are contiguous on mbuf */ |
1563 | void * |
1564 | tcp_ctlinput(int cmd, const struct sockaddr *sa, void *v) |
1565 | { |
1566 | struct ip *ip = v; |
1567 | struct tcphdr *th; |
1568 | struct icmp *icp; |
1569 | extern const int inetctlerrmap[]; |
1570 | void (*notify)(struct inpcb *, int) = tcp_notify; |
1571 | int errno; |
1572 | int nmatch; |
1573 | struct tcpcb *tp; |
1574 | u_int mtu; |
1575 | tcp_seq seq; |
1576 | struct inpcb *inp; |
1577 | #ifdef INET6 |
1578 | struct in6pcb *in6p; |
1579 | struct in6_addr src6, dst6; |
1580 | #endif |
1581 | |
1582 | if (sa->sa_family != AF_INET || |
1583 | sa->sa_len != sizeof(struct sockaddr_in)) |
1584 | return NULL; |
1585 | if ((unsigned)cmd >= PRC_NCMDS) |
1586 | return NULL; |
1587 | errno = inetctlerrmap[cmd]; |
1588 | if (cmd == PRC_QUENCH) |
1589 | /* |
1590 | * Don't honor ICMP Source Quench messages meant for |
1591 | * TCP connections. |
1592 | */ |
1593 | return NULL; |
1594 | else if (PRC_IS_REDIRECT(cmd)) |
1595 | notify = in_rtchange, ip = 0; |
1596 | else if (cmd == PRC_MSGSIZE && ip && ip->ip_v == 4) { |
1597 | /* |
1598 | * Check to see if we have a valid TCP connection |
1599 | * corresponding to the address in the ICMP message |
1600 | * payload. |
1601 | * |
1602 | * Boundary check is made in icmp_input(), with ICMP_ADVLENMIN. |
1603 | */ |
1604 | th = (struct tcphdr *)((char *)ip + (ip->ip_hl << 2)); |
1605 | #ifdef INET6 |
1606 | in6_in_2_v4mapin6(&ip->ip_src, &src6); |
1607 | in6_in_2_v4mapin6(&ip->ip_dst, &dst6); |
1608 | #endif |
1609 | if ((inp = in_pcblookup_connect(&tcbtable, ip->ip_dst, |
1610 | th->th_dport, ip->ip_src, th->th_sport, 0)) != NULL) |
1611 | #ifdef INET6 |
1612 | in6p = NULL; |
1613 | #else |
1614 | ; |
1615 | #endif |
1616 | #ifdef INET6 |
1617 | else if ((in6p = in6_pcblookup_connect(&tcbtable, &dst6, |
1618 | th->th_dport, &src6, th->th_sport, 0, 0)) != NULL) |
1619 | ; |
1620 | #endif |
1621 | else |
1622 | return NULL; |
1623 | |
1624 | /* |
1625 | * Now that we've validated that we are actually communicating |
1626 | * with the host indicated in the ICMP message, locate the |
1627 | * ICMP header, recalculate the new MTU, and create the |
1628 | * corresponding routing entry. |
1629 | */ |
1630 | icp = (struct icmp *)((char *)ip - |
1631 | offsetof(struct icmp, icmp_ip)); |
1632 | if (inp) { |
1633 | if ((tp = intotcpcb(inp)) == NULL) |
1634 | return NULL; |
1635 | } |
1636 | #ifdef INET6 |
1637 | else if (in6p) { |
1638 | if ((tp = in6totcpcb(in6p)) == NULL) |
1639 | return NULL; |
1640 | } |
1641 | #endif |
1642 | else |
1643 | return NULL; |
1644 | seq = ntohl(th->th_seq); |
1645 | if (SEQ_LT(seq, tp->snd_una) || SEQ_GT(seq, tp->snd_max)) |
1646 | return NULL; |
1647 | /* |
1648 | * If the ICMP message advertises a Next-Hop MTU |
1649 | * equal or larger than the maximum packet size we have |
1650 | * ever sent, drop the message. |
1651 | */ |
1652 | mtu = (u_int)ntohs(icp->icmp_nextmtu); |
1653 | if (mtu >= tp->t_pmtud_mtu_sent) |
1654 | return NULL; |
1655 | if (mtu >= tcp_hdrsz(tp) + tp->t_pmtud_mss_acked) { |
1656 | /* |
1657 | * Calculate new MTU, and create corresponding |
1658 | * route (traditional PMTUD). |
1659 | */ |
1660 | tp->t_flags &= ~TF_PMTUD_PEND; |
1661 | icmp_mtudisc(icp, ip->ip_dst); |
1662 | } else { |
1663 | /* |
1664 | * Record the information got in the ICMP |
1665 | * message; act on it later. |
1666 | * If we had already recorded an ICMP message, |
1667 | * replace the old one only if the new message |
1668 | * refers to an older TCP segment |
1669 | */ |
1670 | if (tp->t_flags & TF_PMTUD_PEND) { |
1671 | if (SEQ_LT(tp->t_pmtud_th_seq, seq)) |
1672 | return NULL; |
1673 | } else |
1674 | tp->t_flags |= TF_PMTUD_PEND; |
1675 | tp->t_pmtud_th_seq = seq; |
1676 | tp->t_pmtud_nextmtu = icp->icmp_nextmtu; |
1677 | tp->t_pmtud_ip_len = icp->icmp_ip.ip_len; |
1678 | tp->t_pmtud_ip_hl = icp->icmp_ip.ip_hl; |
1679 | } |
1680 | return NULL; |
1681 | } else if (cmd == PRC_HOSTDEAD) |
1682 | ip = 0; |
1683 | else if (errno == 0) |
1684 | return NULL; |
1685 | if (ip && ip->ip_v == 4 && sa->sa_family == AF_INET) { |
1686 | th = (struct tcphdr *)((char *)ip + (ip->ip_hl << 2)); |
1687 | nmatch = in_pcbnotify(&tcbtable, satocsin(sa)->sin_addr, |
1688 | th->th_dport, ip->ip_src, th->th_sport, errno, notify); |
1689 | if (nmatch == 0 && syn_cache_count && |
1690 | (inetctlerrmap[cmd] == EHOSTUNREACH || |
1691 | inetctlerrmap[cmd] == ENETUNREACH || |
1692 | inetctlerrmap[cmd] == EHOSTDOWN)) { |
1693 | struct sockaddr_in sin; |
1694 | memset(&sin, 0, sizeof(sin)); |
1695 | sin.sin_len = sizeof(sin); |
1696 | sin.sin_family = AF_INET; |
1697 | sin.sin_port = th->th_sport; |
1698 | sin.sin_addr = ip->ip_src; |
1699 | syn_cache_unreach((struct sockaddr *)&sin, sa, th); |
1700 | } |
1701 | |
1702 | /* XXX mapped address case */ |
1703 | } else |
1704 | in_pcbnotifyall(&tcbtable, satocsin(sa)->sin_addr, errno, |
1705 | notify); |
1706 | return NULL; |
1707 | } |
1708 | |
1709 | /* |
1710 | * When a source quench is received, we are being notified of congestion. |
1711 | * Close the congestion window down to the Loss Window (one segment). |
1712 | * We will gradually open it again as we proceed. |
1713 | */ |
1714 | void |
1715 | tcp_quench(struct inpcb *inp, int errno) |
1716 | { |
1717 | struct tcpcb *tp = intotcpcb(inp); |
1718 | |
1719 | if (tp) { |
1720 | tp->snd_cwnd = tp->t_segsz; |
1721 | tp->t_bytes_acked = 0; |
1722 | } |
1723 | } |
1724 | #endif |
1725 | |
1726 | #ifdef INET6 |
1727 | void |
1728 | tcp6_quench(struct in6pcb *in6p, int errno) |
1729 | { |
1730 | struct tcpcb *tp = in6totcpcb(in6p); |
1731 | |
1732 | if (tp) { |
1733 | tp->snd_cwnd = tp->t_segsz; |
1734 | tp->t_bytes_acked = 0; |
1735 | } |
1736 | } |
1737 | #endif |
1738 | |
1739 | #ifdef INET |
1740 | /* |
1741 | * Path MTU Discovery handlers. |
1742 | */ |
1743 | void |
1744 | tcp_mtudisc_callback(struct in_addr faddr) |
1745 | { |
1746 | #ifdef INET6 |
1747 | struct in6_addr in6; |
1748 | #endif |
1749 | |
1750 | in_pcbnotifyall(&tcbtable, faddr, EMSGSIZE, tcp_mtudisc); |
1751 | #ifdef INET6 |
1752 | in6_in_2_v4mapin6(&faddr, &in6); |
1753 | tcp6_mtudisc_callback(&in6); |
1754 | #endif |
1755 | } |
1756 | |
1757 | /* |
1758 | * On receipt of path MTU corrections, flush old route and replace it |
1759 | * with the new one. Retransmit all unacknowledged packets, to ensure |
1760 | * that all packets will be received. |
1761 | */ |
1762 | void |
1763 | tcp_mtudisc(struct inpcb *inp, int errno) |
1764 | { |
1765 | struct tcpcb *tp = intotcpcb(inp); |
1766 | struct rtentry *rt; |
1767 | |
1768 | if (tp == NULL) |
1769 | return; |
1770 | |
1771 | rt = in_pcbrtentry(inp); |
1772 | if (rt != NULL) { |
1773 | /* |
1774 | * If this was not a host route, remove and realloc. |
1775 | */ |
1776 | if ((rt->rt_flags & RTF_HOST) == 0) { |
1777 | in_rtchange(inp, errno); |
1778 | if ((rt = in_pcbrtentry(inp)) == NULL) |
1779 | return; |
1780 | } |
1781 | |
1782 | /* |
1783 | * Slow start out of the error condition. We |
1784 | * use the MTU because we know it's smaller |
1785 | * than the previously transmitted segment. |
1786 | * |
1787 | * Note: This is more conservative than the |
1788 | * suggestion in draft-floyd-incr-init-win-03. |
1789 | */ |
1790 | if (rt->rt_rmx.rmx_mtu != 0) |
1791 | tp->snd_cwnd = |
1792 | TCP_INITIAL_WINDOW(tcp_init_win, |
1793 | rt->rt_rmx.rmx_mtu); |
1794 | } |
1795 | |
1796 | /* |
1797 | * Resend unacknowledged packets. |
1798 | */ |
1799 | tp->snd_nxt = tp->sack_newdata = tp->snd_una; |
1800 | tcp_output(tp); |
1801 | } |
1802 | #endif /* INET */ |
1803 | |
1804 | #ifdef INET6 |
1805 | /* |
1806 | * Path MTU Discovery handlers. |
1807 | */ |
1808 | void |
1809 | tcp6_mtudisc_callback(struct in6_addr *faddr) |
1810 | { |
1811 | struct sockaddr_in6 sin6; |
1812 | |
1813 | memset(&sin6, 0, sizeof(sin6)); |
1814 | sin6.sin6_family = AF_INET6; |
1815 | sin6.sin6_len = sizeof(struct sockaddr_in6); |
1816 | sin6.sin6_addr = *faddr; |
1817 | (void) in6_pcbnotify(&tcbtable, (struct sockaddr *)&sin6, 0, |
1818 | (const struct sockaddr *)&sa6_any, 0, PRC_MSGSIZE, NULL, tcp6_mtudisc); |
1819 | } |
1820 | |
1821 | void |
1822 | tcp6_mtudisc(struct in6pcb *in6p, int errno) |
1823 | { |
1824 | struct tcpcb *tp = in6totcpcb(in6p); |
1825 | struct rtentry *rt; |
1826 | |
1827 | if (tp == NULL) |
1828 | return; |
1829 | |
1830 | rt = in6_pcbrtentry(in6p); |
1831 | if (rt != NULL) { |
1832 | /* |
1833 | * If this was not a host route, remove and realloc. |
1834 | */ |
1835 | if ((rt->rt_flags & RTF_HOST) == 0) { |
1836 | in6_rtchange(in6p, errno); |
1837 | rt = in6_pcbrtentry(in6p); |
1838 | if (rt == NULL) |
1839 | return; |
1840 | } |
1841 | |
1842 | /* |
1843 | * Slow start out of the error condition. We |
1844 | * use the MTU because we know it's smaller |
1845 | * than the previously transmitted segment. |
1846 | * |
1847 | * Note: This is more conservative than the |
1848 | * suggestion in draft-floyd-incr-init-win-03. |
1849 | */ |
1850 | if (rt->rt_rmx.rmx_mtu != 0) { |
1851 | tp->snd_cwnd = TCP_INITIAL_WINDOW(tcp_init_win, |
1852 | rt->rt_rmx.rmx_mtu); |
1853 | } |
1854 | } |
1855 | |
1856 | /* |
1857 | * Resend unacknowledged packets. |
1858 | */ |
1859 | tp->snd_nxt = tp->sack_newdata = tp->snd_una; |
1860 | tcp_output(tp); |
1861 | } |
1862 | #endif /* INET6 */ |
1863 | |
1864 | /* |
1865 | * Compute the MSS to advertise to the peer. Called only during |
1866 | * the 3-way handshake. If we are the server (peer initiated |
1867 | * connection), we are called with a pointer to the interface |
1868 | * on which the SYN packet arrived. If we are the client (we |
1869 | * initiated connection), we are called with a pointer to the |
1870 | * interface out which this connection should go. |
1871 | * |
1872 | * NOTE: Do not subtract IP option/extension header size nor IPsec |
1873 | * header size from MSS advertisement. MSS option must hold the maximum |
1874 | * segment size we can accept, so it must always be: |
1875 | * max(if mtu) - ip header - tcp header |
1876 | */ |
1877 | u_long |
1878 | tcp_mss_to_advertise(const struct ifnet *ifp, int af) |
1879 | { |
1880 | extern u_long in_maxmtu; |
1881 | u_long mss = 0; |
1882 | u_long hdrsiz; |
1883 | |
1884 | /* |
1885 | * In order to avoid defeating path MTU discovery on the peer, |
1886 | * we advertise the max MTU of all attached networks as our MSS, |
1887 | * per RFC 1191, section 3.1. |
1888 | * |
1889 | * We provide the option to advertise just the MTU of |
1890 | * the interface on which we hope this connection will |
1891 | * be receiving. If we are responding to a SYN, we |
1892 | * will have a pretty good idea about this, but when |
1893 | * initiating a connection there is a bit more doubt. |
1894 | * |
1895 | * We also need to ensure that loopback has a large enough |
1896 | * MSS, as the loopback MTU is never included in in_maxmtu. |
1897 | */ |
1898 | |
1899 | if (ifp != NULL) |
1900 | switch (af) { |
1901 | case AF_INET: |
1902 | mss = ifp->if_mtu; |
1903 | break; |
1904 | #ifdef INET6 |
1905 | case AF_INET6: |
1906 | mss = IN6_LINKMTU(ifp); |
1907 | break; |
1908 | #endif |
1909 | } |
1910 | |
1911 | if (tcp_mss_ifmtu == 0) |
1912 | switch (af) { |
1913 | case AF_INET: |
1914 | mss = max(in_maxmtu, mss); |
1915 | break; |
1916 | #ifdef INET6 |
1917 | case AF_INET6: |
1918 | mss = max(in6_maxmtu, mss); |
1919 | break; |
1920 | #endif |
1921 | } |
1922 | |
1923 | switch (af) { |
1924 | case AF_INET: |
1925 | hdrsiz = sizeof(struct ip); |
1926 | break; |
1927 | #ifdef INET6 |
1928 | case AF_INET6: |
1929 | hdrsiz = sizeof(struct ip6_hdr); |
1930 | break; |
1931 | #endif |
1932 | default: |
1933 | hdrsiz = 0; |
1934 | break; |
1935 | } |
1936 | hdrsiz += sizeof(struct tcphdr); |
1937 | if (mss > hdrsiz) |
1938 | mss -= hdrsiz; |
1939 | |
1940 | mss = max(tcp_mssdflt, mss); |
1941 | return (mss); |
1942 | } |
1943 | |
1944 | /* |
1945 | * Set connection variables based on the peer's advertised MSS. |
1946 | * We are passed the TCPCB for the actual connection. If we |
1947 | * are the server, we are called by the compressed state engine |
1948 | * when the 3-way handshake is complete. If we are the client, |
1949 | * we are called when we receive the SYN,ACK from the server. |
1950 | * |
1951 | * NOTE: Our advertised MSS value must be initialized in the TCPCB |
1952 | * before this routine is called! |
1953 | */ |
1954 | void |
1955 | tcp_mss_from_peer(struct tcpcb *tp, int offer) |
1956 | { |
1957 | struct socket *so; |
1958 | #if defined(RTV_SPIPE) || defined(RTV_SSTHRESH) |
1959 | struct rtentry *rt; |
1960 | #endif |
1961 | u_long bufsize; |
1962 | int mss; |
1963 | |
1964 | #ifdef DIAGNOSTIC |
1965 | if (tp->t_inpcb && tp->t_in6pcb) |
1966 | panic("tcp_mss_from_peer: both t_inpcb and t_in6pcb are set" ); |
1967 | #endif |
1968 | so = NULL; |
1969 | rt = NULL; |
1970 | #ifdef INET |
1971 | if (tp->t_inpcb) { |
1972 | so = tp->t_inpcb->inp_socket; |
1973 | #if defined(RTV_SPIPE) || defined(RTV_SSTHRESH) |
1974 | rt = in_pcbrtentry(tp->t_inpcb); |
1975 | #endif |
1976 | } |
1977 | #endif |
1978 | #ifdef INET6 |
1979 | if (tp->t_in6pcb) { |
1980 | so = tp->t_in6pcb->in6p_socket; |
1981 | #if defined(RTV_SPIPE) || defined(RTV_SSTHRESH) |
1982 | rt = in6_pcbrtentry(tp->t_in6pcb); |
1983 | #endif |
1984 | } |
1985 | #endif |
1986 | |
1987 | /* |
1988 | * As per RFC1122, use the default MSS value, unless they |
1989 | * sent us an offer. Do not accept offers less than 256 bytes. |
1990 | */ |
1991 | mss = tcp_mssdflt; |
1992 | if (offer) |
1993 | mss = offer; |
1994 | mss = max(mss, 256); /* sanity */ |
1995 | tp->t_peermss = mss; |
1996 | mss -= tcp_optlen(tp); |
1997 | #ifdef INET |
1998 | if (tp->t_inpcb) |
1999 | mss -= ip_optlen(tp->t_inpcb); |
2000 | #endif |
2001 | #ifdef INET6 |
2002 | if (tp->t_in6pcb) |
2003 | mss -= ip6_optlen(tp->t_in6pcb); |
2004 | #endif |
2005 | |
2006 | /* |
2007 | * If there's a pipesize, change the socket buffer to that size. |
2008 | * Make the socket buffer an integral number of MSS units. If |
2009 | * the MSS is larger than the socket buffer, artificially decrease |
2010 | * the MSS. |
2011 | */ |
2012 | #ifdef RTV_SPIPE |
2013 | if (rt != NULL && rt->rt_rmx.rmx_sendpipe != 0) |
2014 | bufsize = rt->rt_rmx.rmx_sendpipe; |
2015 | else |
2016 | #endif |
2017 | { |
2018 | KASSERT(so != NULL); |
2019 | bufsize = so->so_snd.sb_hiwat; |
2020 | } |
2021 | if (bufsize < mss) |
2022 | mss = bufsize; |
2023 | else { |
2024 | bufsize = roundup(bufsize, mss); |
2025 | if (bufsize > sb_max) |
2026 | bufsize = sb_max; |
2027 | (void) sbreserve(&so->so_snd, bufsize, so); |
2028 | } |
2029 | tp->t_segsz = mss; |
2030 | |
2031 | #ifdef RTV_SSTHRESH |
2032 | if (rt != NULL && rt->rt_rmx.rmx_ssthresh) { |
2033 | /* |
2034 | * There's some sort of gateway or interface buffer |
2035 | * limit on the path. Use this to set the slow |
2036 | * start threshold, but set the threshold to no less |
2037 | * than 2 * MSS. |
2038 | */ |
2039 | tp->snd_ssthresh = max(2 * mss, rt->rt_rmx.rmx_ssthresh); |
2040 | } |
2041 | #endif |
2042 | } |
2043 | |
2044 | /* |
2045 | * Processing necessary when a TCP connection is established. |
2046 | */ |
2047 | void |
2048 | tcp_established(struct tcpcb *tp) |
2049 | { |
2050 | struct socket *so; |
2051 | #ifdef RTV_RPIPE |
2052 | struct rtentry *rt; |
2053 | #endif |
2054 | u_long bufsize; |
2055 | |
2056 | #ifdef DIAGNOSTIC |
2057 | if (tp->t_inpcb && tp->t_in6pcb) |
2058 | panic("tcp_established: both t_inpcb and t_in6pcb are set" ); |
2059 | #endif |
2060 | so = NULL; |
2061 | rt = NULL; |
2062 | #ifdef INET |
2063 | /* This is a while() to reduce the dreadful stairstepping below */ |
2064 | while (tp->t_inpcb) { |
2065 | so = tp->t_inpcb->inp_socket; |
2066 | #if defined(RTV_RPIPE) |
2067 | rt = in_pcbrtentry(tp->t_inpcb); |
2068 | #endif |
2069 | if (__predict_true(tcp_msl_enable)) { |
2070 | if (tp->t_inpcb->inp_laddr.s_addr == INADDR_LOOPBACK) { |
2071 | tp->t_msl = tcp_msl_loop ? tcp_msl_loop : (TCPTV_MSL >> 2); |
2072 | break; |
2073 | } |
2074 | |
2075 | if (__predict_false(tcp_rttlocal)) { |
2076 | /* This may be adjusted by tcp_input */ |
2077 | tp->t_msl = tcp_msl_local ? tcp_msl_local : (TCPTV_MSL >> 1); |
2078 | break; |
2079 | } |
2080 | if (in_localaddr(tp->t_inpcb->inp_faddr)) { |
2081 | tp->t_msl = tcp_msl_local ? tcp_msl_local : (TCPTV_MSL >> 1); |
2082 | break; |
2083 | } |
2084 | } |
2085 | tp->t_msl = tcp_msl_remote ? tcp_msl_remote : TCPTV_MSL; |
2086 | break; |
2087 | } |
2088 | #endif |
2089 | #ifdef INET6 |
2090 | /* The !tp->t_inpcb lets the compiler know it can't be v4 *and* v6 */ |
2091 | while (!tp->t_inpcb && tp->t_in6pcb) { |
2092 | so = tp->t_in6pcb->in6p_socket; |
2093 | #if defined(RTV_RPIPE) |
2094 | rt = in6_pcbrtentry(tp->t_in6pcb); |
2095 | #endif |
2096 | if (__predict_true(tcp_msl_enable)) { |
2097 | extern const struct in6_addr in6addr_loopback; |
2098 | |
2099 | if (IN6_ARE_ADDR_EQUAL(&tp->t_in6pcb->in6p_laddr, |
2100 | &in6addr_loopback)) { |
2101 | tp->t_msl = tcp_msl_loop ? tcp_msl_loop : (TCPTV_MSL >> 2); |
2102 | break; |
2103 | } |
2104 | |
2105 | if (__predict_false(tcp_rttlocal)) { |
2106 | /* This may be adjusted by tcp_input */ |
2107 | tp->t_msl = tcp_msl_local ? tcp_msl_local : (TCPTV_MSL >> 1); |
2108 | break; |
2109 | } |
2110 | if (in6_localaddr(&tp->t_in6pcb->in6p_faddr)) { |
2111 | tp->t_msl = tcp_msl_local ? tcp_msl_local : (TCPTV_MSL >> 1); |
2112 | break; |
2113 | } |
2114 | } |
2115 | tp->t_msl = tcp_msl_remote ? tcp_msl_remote : TCPTV_MSL; |
2116 | break; |
2117 | } |
2118 | #endif |
2119 | |
2120 | tp->t_state = TCPS_ESTABLISHED; |
2121 | TCP_TIMER_ARM(tp, TCPT_KEEP, tp->t_keepidle); |
2122 | |
2123 | #ifdef RTV_RPIPE |
2124 | if (rt != NULL && rt->rt_rmx.rmx_recvpipe != 0) |
2125 | bufsize = rt->rt_rmx.rmx_recvpipe; |
2126 | else |
2127 | #endif |
2128 | { |
2129 | KASSERT(so != NULL); |
2130 | bufsize = so->so_rcv.sb_hiwat; |
2131 | } |
2132 | if (bufsize > tp->t_ourmss) { |
2133 | bufsize = roundup(bufsize, tp->t_ourmss); |
2134 | if (bufsize > sb_max) |
2135 | bufsize = sb_max; |
2136 | (void) sbreserve(&so->so_rcv, bufsize, so); |
2137 | } |
2138 | } |
2139 | |
2140 | /* |
2141 | * Check if there's an initial rtt or rttvar. Convert from the |
2142 | * route-table units to scaled multiples of the slow timeout timer. |
2143 | * Called only during the 3-way handshake. |
2144 | */ |
2145 | void |
2146 | tcp_rmx_rtt(struct tcpcb *tp) |
2147 | { |
2148 | #ifdef RTV_RTT |
2149 | struct rtentry *rt = NULL; |
2150 | int rtt; |
2151 | |
2152 | #ifdef DIAGNOSTIC |
2153 | if (tp->t_inpcb && tp->t_in6pcb) |
2154 | panic("tcp_rmx_rtt: both t_inpcb and t_in6pcb are set" ); |
2155 | #endif |
2156 | #ifdef INET |
2157 | if (tp->t_inpcb) |
2158 | rt = in_pcbrtentry(tp->t_inpcb); |
2159 | #endif |
2160 | #ifdef INET6 |
2161 | if (tp->t_in6pcb) |
2162 | rt = in6_pcbrtentry(tp->t_in6pcb); |
2163 | #endif |
2164 | if (rt == NULL) |
2165 | return; |
2166 | |
2167 | if (tp->t_srtt == 0 && (rtt = rt->rt_rmx.rmx_rtt)) { |
2168 | /* |
2169 | * XXX The lock bit for MTU indicates that the value |
2170 | * is also a minimum value; this is subject to time. |
2171 | */ |
2172 | if (rt->rt_rmx.rmx_locks & RTV_RTT) |
2173 | TCPT_RANGESET(tp->t_rttmin, |
2174 | rtt / (RTM_RTTUNIT / PR_SLOWHZ), |
2175 | TCPTV_MIN, TCPTV_REXMTMAX); |
2176 | tp->t_srtt = rtt / |
2177 | ((RTM_RTTUNIT / PR_SLOWHZ) >> (TCP_RTT_SHIFT + 2)); |
2178 | if (rt->rt_rmx.rmx_rttvar) { |
2179 | tp->t_rttvar = rt->rt_rmx.rmx_rttvar / |
2180 | ((RTM_RTTUNIT / PR_SLOWHZ) >> |
2181 | (TCP_RTTVAR_SHIFT + 2)); |
2182 | } else { |
2183 | /* Default variation is +- 1 rtt */ |
2184 | tp->t_rttvar = |
2185 | tp->t_srtt >> (TCP_RTT_SHIFT - TCP_RTTVAR_SHIFT); |
2186 | } |
2187 | TCPT_RANGESET(tp->t_rxtcur, |
2188 | ((tp->t_srtt >> 2) + tp->t_rttvar) >> (1 + 2), |
2189 | tp->t_rttmin, TCPTV_REXMTMAX); |
2190 | } |
2191 | #endif |
2192 | } |
2193 | |
2194 | tcp_seq tcp_iss_seq = 0; /* tcp initial seq # */ |
2195 | |
2196 | /* |
2197 | * Get a new sequence value given a tcp control block |
2198 | */ |
2199 | tcp_seq |
2200 | tcp_new_iss(struct tcpcb *tp, tcp_seq addin) |
2201 | { |
2202 | |
2203 | #ifdef INET |
2204 | if (tp->t_inpcb != NULL) { |
2205 | return (tcp_new_iss1(&tp->t_inpcb->inp_laddr, |
2206 | &tp->t_inpcb->inp_faddr, tp->t_inpcb->inp_lport, |
2207 | tp->t_inpcb->inp_fport, sizeof(tp->t_inpcb->inp_laddr), |
2208 | addin)); |
2209 | } |
2210 | #endif |
2211 | #ifdef INET6 |
2212 | if (tp->t_in6pcb != NULL) { |
2213 | return (tcp_new_iss1(&tp->t_in6pcb->in6p_laddr, |
2214 | &tp->t_in6pcb->in6p_faddr, tp->t_in6pcb->in6p_lport, |
2215 | tp->t_in6pcb->in6p_fport, sizeof(tp->t_in6pcb->in6p_laddr), |
2216 | addin)); |
2217 | } |
2218 | #endif |
2219 | /* Not possible. */ |
2220 | panic("tcp_new_iss" ); |
2221 | } |
2222 | |
2223 | static u_int8_t tcp_iss_secret[16]; /* 128 bits; should be plenty */ |
2224 | |
2225 | /* |
2226 | * Initialize RFC 1948 ISS Secret |
2227 | */ |
2228 | static int |
2229 | tcp_iss_secret_init(void) |
2230 | { |
2231 | cprng_strong(kern_cprng, |
2232 | tcp_iss_secret, sizeof(tcp_iss_secret), 0); |
2233 | |
2234 | return 0; |
2235 | } |
2236 | |
2237 | /* |
2238 | * This routine actually generates a new TCP initial sequence number. |
2239 | */ |
2240 | tcp_seq |
2241 | tcp_new_iss1(void *laddr, void *faddr, u_int16_t lport, u_int16_t fport, |
2242 | size_t addrsz, tcp_seq addin) |
2243 | { |
2244 | tcp_seq tcp_iss; |
2245 | |
2246 | if (tcp_do_rfc1948) { |
2247 | MD5_CTX ctx; |
2248 | u_int8_t hash[16]; /* XXX MD5 knowledge */ |
2249 | static ONCE_DECL(tcp_iss_secret_control); |
2250 | |
2251 | /* |
2252 | * If we haven't been here before, initialize our cryptographic |
2253 | * hash secret. |
2254 | */ |
2255 | RUN_ONCE(&tcp_iss_secret_control, tcp_iss_secret_init); |
2256 | |
2257 | /* |
2258 | * Compute the base value of the ISS. It is a hash |
2259 | * of (saddr, sport, daddr, dport, secret). |
2260 | */ |
2261 | MD5Init(&ctx); |
2262 | |
2263 | MD5Update(&ctx, (u_char *) laddr, addrsz); |
2264 | MD5Update(&ctx, (u_char *) &lport, sizeof(lport)); |
2265 | |
2266 | MD5Update(&ctx, (u_char *) faddr, addrsz); |
2267 | MD5Update(&ctx, (u_char *) &fport, sizeof(fport)); |
2268 | |
2269 | MD5Update(&ctx, tcp_iss_secret, sizeof(tcp_iss_secret)); |
2270 | |
2271 | MD5Final(hash, &ctx); |
2272 | |
2273 | memcpy(&tcp_iss, hash, sizeof(tcp_iss)); |
2274 | |
2275 | /* |
2276 | * Now increment our "timer", and add it in to |
2277 | * the computed value. |
2278 | * |
2279 | * XXX Use `addin'? |
2280 | * XXX TCP_ISSINCR too large to use? |
2281 | */ |
2282 | tcp_iss_seq += TCP_ISSINCR; |
2283 | #ifdef TCPISS_DEBUG |
2284 | printf("ISS hash 0x%08x, " , tcp_iss); |
2285 | #endif |
2286 | tcp_iss += tcp_iss_seq + addin; |
2287 | #ifdef TCPISS_DEBUG |
2288 | printf("new ISS 0x%08x\n" , tcp_iss); |
2289 | #endif |
2290 | } else { |
2291 | /* |
2292 | * Randomize. |
2293 | */ |
2294 | tcp_iss = cprng_fast32(); |
2295 | |
2296 | /* |
2297 | * If we were asked to add some amount to a known value, |
2298 | * we will take a random value obtained above, mask off |
2299 | * the upper bits, and add in the known value. We also |
2300 | * add in a constant to ensure that we are at least a |
2301 | * certain distance from the original value. |
2302 | * |
2303 | * This is used when an old connection is in timed wait |
2304 | * and we have a new one coming in, for instance. |
2305 | */ |
2306 | if (addin != 0) { |
2307 | #ifdef TCPISS_DEBUG |
2308 | printf("Random %08x, " , tcp_iss); |
2309 | #endif |
2310 | tcp_iss &= TCP_ISS_RANDOM_MASK; |
2311 | tcp_iss += addin + TCP_ISSINCR; |
2312 | #ifdef TCPISS_DEBUG |
2313 | printf("Old ISS %08x, ISS %08x\n" , addin, tcp_iss); |
2314 | #endif |
2315 | } else { |
2316 | tcp_iss &= TCP_ISS_RANDOM_MASK; |
2317 | tcp_iss += tcp_iss_seq; |
2318 | tcp_iss_seq += TCP_ISSINCR; |
2319 | #ifdef TCPISS_DEBUG |
2320 | printf("ISS %08x\n" , tcp_iss); |
2321 | #endif |
2322 | } |
2323 | } |
2324 | |
2325 | if (tcp_compat_42) { |
2326 | /* |
2327 | * Limit it to the positive range for really old TCP |
2328 | * implementations. |
2329 | * Just AND off the top bit instead of checking if |
2330 | * is set first - saves a branch 50% of the time. |
2331 | */ |
2332 | tcp_iss &= 0x7fffffff; /* XXX */ |
2333 | } |
2334 | |
2335 | return (tcp_iss); |
2336 | } |
2337 | |
2338 | #if defined(IPSEC) |
2339 | /* compute ESP/AH header size for TCP, including outer IP header. */ |
2340 | size_t |
2341 | ipsec4_hdrsiz_tcp(struct tcpcb *tp) |
2342 | { |
2343 | struct inpcb *inp; |
2344 | size_t hdrsiz; |
2345 | |
2346 | /* XXX mapped addr case (tp->t_in6pcb) */ |
2347 | if (!tp || !tp->t_template || !(inp = tp->t_inpcb)) |
2348 | return 0; |
2349 | switch (tp->t_family) { |
2350 | case AF_INET: |
2351 | /* XXX: should use currect direction. */ |
2352 | hdrsiz = ipsec4_hdrsiz(tp->t_template, IPSEC_DIR_OUTBOUND, inp); |
2353 | break; |
2354 | default: |
2355 | hdrsiz = 0; |
2356 | break; |
2357 | } |
2358 | |
2359 | return hdrsiz; |
2360 | } |
2361 | |
2362 | #ifdef INET6 |
2363 | size_t |
2364 | ipsec6_hdrsiz_tcp(struct tcpcb *tp) |
2365 | { |
2366 | struct in6pcb *in6p; |
2367 | size_t hdrsiz; |
2368 | |
2369 | if (!tp || !tp->t_template || !(in6p = tp->t_in6pcb)) |
2370 | return 0; |
2371 | switch (tp->t_family) { |
2372 | case AF_INET6: |
2373 | /* XXX: should use currect direction. */ |
2374 | hdrsiz = ipsec6_hdrsiz(tp->t_template, IPSEC_DIR_OUTBOUND, in6p); |
2375 | break; |
2376 | case AF_INET: |
2377 | /* mapped address case - tricky */ |
2378 | default: |
2379 | hdrsiz = 0; |
2380 | break; |
2381 | } |
2382 | |
2383 | return hdrsiz; |
2384 | } |
2385 | #endif |
2386 | #endif /*IPSEC*/ |
2387 | |
2388 | /* |
2389 | * Determine the length of the TCP options for this connection. |
2390 | * |
2391 | * XXX: What do we do for SACK, when we add that? Just reserve |
2392 | * all of the space? Otherwise we can't exactly be incrementing |
2393 | * cwnd by an amount that varies depending on the amount we last |
2394 | * had to SACK! |
2395 | */ |
2396 | |
2397 | u_int |
2398 | tcp_optlen(struct tcpcb *tp) |
2399 | { |
2400 | u_int optlen; |
2401 | |
2402 | optlen = 0; |
2403 | if ((tp->t_flags & (TF_REQ_TSTMP|TF_RCVD_TSTMP|TF_NOOPT)) == |
2404 | (TF_REQ_TSTMP | TF_RCVD_TSTMP)) |
2405 | optlen += TCPOLEN_TSTAMP_APPA; |
2406 | |
2407 | #ifdef TCP_SIGNATURE |
2408 | if (tp->t_flags & TF_SIGNATURE) |
2409 | optlen += TCPOLEN_SIGNATURE + 2; |
2410 | #endif /* TCP_SIGNATURE */ |
2411 | |
2412 | return optlen; |
2413 | } |
2414 | |
2415 | u_int |
2416 | tcp_hdrsz(struct tcpcb *tp) |
2417 | { |
2418 | u_int hlen; |
2419 | |
2420 | switch (tp->t_family) { |
2421 | #ifdef INET6 |
2422 | case AF_INET6: |
2423 | hlen = sizeof(struct ip6_hdr); |
2424 | break; |
2425 | #endif |
2426 | case AF_INET: |
2427 | hlen = sizeof(struct ip); |
2428 | break; |
2429 | default: |
2430 | hlen = 0; |
2431 | break; |
2432 | } |
2433 | hlen += sizeof(struct tcphdr); |
2434 | |
2435 | if ((tp->t_flags & (TF_REQ_TSTMP|TF_NOOPT)) == TF_REQ_TSTMP && |
2436 | (tp->t_flags & TF_RCVD_TSTMP) == TF_RCVD_TSTMP) |
2437 | hlen += TCPOLEN_TSTAMP_APPA; |
2438 | #ifdef TCP_SIGNATURE |
2439 | if (tp->t_flags & TF_SIGNATURE) |
2440 | hlen += TCPOLEN_SIGLEN; |
2441 | #endif |
2442 | return hlen; |
2443 | } |
2444 | |
2445 | void |
2446 | tcp_statinc(u_int stat) |
2447 | { |
2448 | |
2449 | KASSERT(stat < TCP_NSTATS); |
2450 | TCP_STATINC(stat); |
2451 | } |
2452 | |
2453 | void |
2454 | tcp_statadd(u_int stat, uint64_t val) |
2455 | { |
2456 | |
2457 | KASSERT(stat < TCP_NSTATS); |
2458 | TCP_STATADD(stat, val); |
2459 | } |
2460 | |