Commit | Line | Data |
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c20f7455 | 1 | /* uipc_socket2.c 4.35 83/01/13 */ |
681ebb17 BJ |
2 | |
3 | #include "../h/param.h" | |
4 | #include "../h/systm.h" | |
5 | #include "../h/dir.h" | |
6 | #include "../h/user.h" | |
7 | #include "../h/proc.h" | |
8 | #include "../h/file.h" | |
9 | #include "../h/inode.h" | |
10 | #include "../h/buf.h" | |
11 | #include "../h/mbuf.h" | |
681ebb17 BJ |
12 | #include "../h/protosw.h" |
13 | #include "../h/socket.h" | |
14 | #include "../h/socketvar.h" | |
681ebb17 BJ |
15 | |
16 | /* | |
17 | * Primitive routines for operating on sockets and socket buffers | |
18 | */ | |
19 | ||
20 | /* | |
21 | * Procedures to manipulate state flags of socket | |
2deddea9 BJ |
22 | * and do appropriate wakeups. Normal sequence from the |
23 | * active (originating) side is that soisconnecting() is | |
24 | * called during processing of connect() call, | |
4c078bb2 BJ |
25 | * resulting in an eventual call to soisconnected() if/when the |
26 | * connection is established. When the connection is torn down | |
27 | * soisdisconnecting() is called during processing of disconnect() call, | |
28 | * and soisdisconnected() is called when the connection to the peer | |
29 | * is totally severed. The semantics of these routines are such that | |
30 | * connectionless protocols can call soisconnected() and soisdisconnected() | |
31 | * only, bypassing the in-progress calls when setting up a ``connection'' | |
32 | * takes no time. | |
33 | * | |
2deddea9 BJ |
34 | * From the passive side, a socket is created with SO_ACCEPTCONN |
35 | * creating two queues of sockets: so_q0 for connections in progress | |
36 | * and so_q for connections already made and awaiting user acceptance. | |
37 | * As a protocol is preparing incoming connections, it creates a socket | |
38 | * structure queued on so_q0 by calling sonewconn(). When the connection | |
39 | * is established, soisconnected() is called, and transfers the | |
40 | * socket structure to so_q, making it available to accept(). | |
41 | * | |
42 | * If a SO_ACCEPTCONN socket is closed with sockets on either | |
43 | * so_q0 or so_q, these sockets are dropped. | |
44 | * | |
45 | * If and when higher level protocols are implemented in | |
4c078bb2 BJ |
46 | * the kernel, the wakeups done here will sometimes |
47 | * be implemented as software-interrupt process scheduling. | |
681ebb17 | 48 | */ |
4c078bb2 | 49 | |
681ebb17 BJ |
50 | soisconnecting(so) |
51 | struct socket *so; | |
52 | { | |
53 | ||
54 | so->so_state &= ~(SS_ISCONNECTED|SS_ISDISCONNECTING); | |
55 | so->so_state |= SS_ISCONNECTING; | |
56 | wakeup((caddr_t)&so->so_timeo); | |
57 | } | |
58 | ||
59 | soisconnected(so) | |
60 | struct socket *so; | |
61 | { | |
2deddea9 | 62 | register struct socket *head = so->so_head; |
681ebb17 | 63 | |
2deddea9 BJ |
64 | if (head) { |
65 | if (soqremque(so, 0) == 0) | |
66 | panic("soisconnected"); | |
67 | soqinsque(head, so, 1); | |
68 | wakeup((caddr_t)&head->so_timeo); | |
69 | } | |
681ebb17 BJ |
70 | so->so_state &= ~(SS_ISCONNECTING|SS_ISDISCONNECTING); |
71 | so->so_state |= SS_ISCONNECTED; | |
72 | wakeup((caddr_t)&so->so_timeo); | |
f957a49a BJ |
73 | sorwakeup(so); |
74 | sowwakeup(so); | |
681ebb17 BJ |
75 | } |
76 | ||
77 | soisdisconnecting(so) | |
78 | struct socket *so; | |
79 | { | |
80 | ||
72857acf | 81 | so->so_state &= ~SS_ISCONNECTING; |
681ebb17 BJ |
82 | so->so_state |= (SS_ISDISCONNECTING|SS_CANTRCVMORE|SS_CANTSENDMORE); |
83 | wakeup((caddr_t)&so->so_timeo); | |
4c078bb2 | 84 | sowwakeup(so); |
b454c3ea | 85 | sorwakeup(so); |
681ebb17 BJ |
86 | } |
87 | ||
88 | soisdisconnected(so) | |
89 | struct socket *so; | |
90 | { | |
91 | ||
92 | so->so_state &= ~(SS_ISCONNECTING|SS_ISCONNECTED|SS_ISDISCONNECTING); | |
93 | so->so_state |= (SS_CANTRCVMORE|SS_CANTSENDMORE); | |
94 | wakeup((caddr_t)&so->so_timeo); | |
95 | sowwakeup(so); | |
96 | sorwakeup(so); | |
97 | } | |
98 | ||
2deddea9 BJ |
99 | /* |
100 | * When an attempt at a new connection is noted on a socket | |
101 | * which accepts connections, sonewconn is called. If the | |
102 | * connection is possible (subject to space constraints, etc.) | |
103 | * then we allocate a new structure, propoerly linked into the | |
104 | * data structure of the original socket, and return this. | |
105 | */ | |
106 | struct socket * | |
107 | sonewconn(head) | |
108 | register struct socket *head; | |
109 | { | |
110 | register struct socket *so; | |
111 | struct mbuf *m; | |
112 | ||
113 | if (head->so_qlen + head->so_q0len > 3 * head->so_qlimit / 2) | |
114 | goto bad; | |
cce93e4b | 115 | m = m_getclr(M_DONTWAIT, MT_SOCKET); |
5fe6f9d1 | 116 | if (m == NULL) |
2deddea9 BJ |
117 | goto bad; |
118 | so = mtod(m, struct socket *); | |
119 | so->so_type = head->so_type; | |
120 | so->so_options = head->so_options &~ SO_ACCEPTCONN; | |
121 | so->so_linger = head->so_linger; | |
f7428e88 | 122 | so->so_state = head->so_state | SS_NOFDREF; |
2deddea9 BJ |
123 | so->so_proto = head->so_proto; |
124 | so->so_timeo = head->so_timeo; | |
125 | so->so_pgrp = head->so_pgrp; | |
126 | soqinsque(head, so, 0); | |
5fe6f9d1 | 127 | if ((*so->so_proto->pr_usrreq)(so, PRU_ATTACH, (struct mbuf *)0, |
c20f7455 | 128 | (struct mbuf *)0)) { |
2deddea9 | 129 | (void) soqremque(so, 0); |
30c36259 | 130 | (void) m_free(m); |
2deddea9 BJ |
131 | goto bad; |
132 | } | |
133 | return (so); | |
134 | bad: | |
135 | return ((struct socket *)0); | |
136 | } | |
137 | ||
138 | soqinsque(head, so, q) | |
139 | register struct socket *head, *so; | |
140 | int q; | |
141 | { | |
142 | ||
143 | so->so_head = head; | |
144 | if (q == 0) { | |
145 | head->so_q0len++; | |
146 | so->so_q0 = head->so_q0; | |
147 | head->so_q0 = so; | |
148 | } else { | |
149 | head->so_qlen++; | |
150 | so->so_q = head->so_q; | |
151 | head->so_q = so; | |
152 | } | |
153 | } | |
154 | ||
155 | soqremque(so, q) | |
156 | register struct socket *so; | |
157 | int q; | |
158 | { | |
159 | register struct socket *head, *prev, *next; | |
160 | ||
161 | head = so->so_head; | |
162 | prev = head; | |
163 | for (;;) { | |
164 | next = q ? prev->so_q : prev->so_q0; | |
165 | if (next == so) | |
166 | break; | |
167 | if (next == head) | |
168 | return (0); | |
169 | prev = next; | |
170 | } | |
171 | if (q == 0) { | |
172 | prev->so_q0 = next->so_q0; | |
173 | head->so_q0len--; | |
174 | } else { | |
175 | prev->so_q = next->so_q; | |
176 | head->so_qlen--; | |
177 | } | |
178 | next->so_q0 = next->so_q = 0; | |
179 | next->so_head = 0; | |
180 | return (1); | |
181 | } | |
182 | ||
4c078bb2 BJ |
183 | /* |
184 | * Socantsendmore indicates that no more data will be sent on the | |
185 | * socket; it would normally be applied to a socket when the user | |
186 | * informs the system that no more data is to be sent, by the protocol | |
187 | * code (in case PRU_SHUTDOWN). Socantrcvmore indicates that no more data | |
188 | * will be received, and will normally be applied to the socket by a | |
189 | * protocol when it detects that the peer will send no more data. | |
190 | * Data queued for reading in the socket may yet be read. | |
191 | */ | |
192 | ||
ae921915 BJ |
193 | socantsendmore(so) |
194 | struct socket *so; | |
195 | { | |
196 | ||
197 | so->so_state |= SS_CANTSENDMORE; | |
198 | sowwakeup(so); | |
199 | } | |
200 | ||
201 | socantrcvmore(so) | |
202 | struct socket *so; | |
203 | { | |
204 | ||
205 | so->so_state |= SS_CANTRCVMORE; | |
206 | sorwakeup(so); | |
207 | } | |
208 | ||
681ebb17 | 209 | /* |
4c078bb2 BJ |
210 | * Socket select/wakeup routines. |
211 | */ | |
212 | ||
213 | /* | |
214 | * Interface routine to select() system | |
215 | * call for sockets. | |
681ebb17 | 216 | */ |
477b2112 | 217 | soselect(so, rw) |
681ebb17 | 218 | register struct socket *so; |
477b2112 | 219 | int rw; |
681ebb17 | 220 | { |
f957a49a | 221 | int s = splnet(); |
681ebb17 | 222 | |
477b2112 BJ |
223 | switch (rw) { |
224 | ||
225 | case FREAD: | |
f957a49a BJ |
226 | if (soreadable(so)) { |
227 | splx(s); | |
681ebb17 | 228 | return (1); |
f957a49a | 229 | } |
681ebb17 | 230 | sbselqueue(&so->so_rcv); |
477b2112 BJ |
231 | break; |
232 | ||
233 | case FWRITE: | |
f957a49a BJ |
234 | if (sowriteable(so)) { |
235 | splx(s); | |
681ebb17 | 236 | return (1); |
f957a49a | 237 | } |
681ebb17 | 238 | sbselqueue(&so->so_snd); |
477b2112 | 239 | break; |
681ebb17 | 240 | } |
f957a49a | 241 | splx(s); |
681ebb17 BJ |
242 | return (0); |
243 | } | |
244 | ||
245 | /* | |
246 | * Queue a process for a select on a socket buffer. | |
247 | */ | |
248 | sbselqueue(sb) | |
249 | struct sockbuf *sb; | |
250 | { | |
251 | register struct proc *p; | |
252 | ||
ae921915 | 253 | if ((p = sb->sb_sel) && p->p_wchan == (caddr_t)&selwait) |
681ebb17 BJ |
254 | sb->sb_flags |= SB_COLL; |
255 | else | |
256 | sb->sb_sel = u.u_procp; | |
257 | } | |
258 | ||
ae921915 BJ |
259 | /* |
260 | * Wait for data to arrive at/drain from a socket buffer. | |
261 | */ | |
262 | sbwait(sb) | |
263 | struct sockbuf *sb; | |
264 | { | |
265 | ||
266 | sb->sb_flags |= SB_WAIT; | |
267 | sleep((caddr_t)&sb->sb_cc, PZERO+1); | |
268 | } | |
269 | ||
681ebb17 BJ |
270 | /* |
271 | * Wakeup processes waiting on a socket buffer. | |
272 | */ | |
273 | sbwakeup(sb) | |
274 | struct sockbuf *sb; | |
275 | { | |
276 | ||
277 | if (sb->sb_sel) { | |
278 | selwakeup(sb->sb_sel, sb->sb_flags & SB_COLL); | |
279 | sb->sb_sel = 0; | |
280 | sb->sb_flags &= ~SB_COLL; | |
281 | } | |
282 | if (sb->sb_flags & SB_WAIT) { | |
283 | sb->sb_flags &= ~SB_WAIT; | |
388ca8bd | 284 | wakeup((caddr_t)&sb->sb_cc); |
681ebb17 BJ |
285 | } |
286 | } | |
287 | ||
4c078bb2 BJ |
288 | /* |
289 | * Socket buffer (struct sockbuf) utility routines. | |
290 | * | |
291 | * Each socket contains two socket buffers: one for sending data and | |
292 | * one for receiving data. Each buffer contains a queue of mbufs, | |
293 | * information about the number of mbufs and amount of data in the | |
294 | * queue, and other fields allowing select() statements and notification | |
295 | * on data availability to be implemented. | |
296 | * | |
297 | * Before using a new socket structure it is first necessary to reserve | |
298 | * buffer space to the socket, by calling sbreserve. This commits | |
299 | * some of the available buffer space in the system buffer pool for the | |
300 | * socket. The space should be released by calling sbrelease when the | |
301 | * socket is destroyed. | |
302 | * | |
303 | * The routine sbappend() is normally called to append new mbufs | |
304 | * to a socket buffer, after checking that adequate space is available | |
305 | * comparing the function spspace() with the amount of data to be added. | |
306 | * Data is normally removed from a socket buffer in a protocol by | |
307 | * first calling m_copy on the socket buffer mbuf chain and sending this | |
308 | * to a peer, and then removing the data from the socket buffer with | |
309 | * sbdrop when the data is acknowledged by the peer (or immediately | |
b454c3ea | 310 | * in the case of unreliable protocols.) |
4c078bb2 BJ |
311 | * |
312 | * Protocols which do not require connections place both source address | |
313 | * and data information in socket buffer queues. The source addresses | |
314 | * are stored in single mbufs after each data item, and are easily found | |
315 | * as the data items are all marked with end of record markers. The | |
316 | * sbappendaddr() routine stores a datum and associated address in | |
317 | * a socket buffer. Note that, unlike sbappend(), this routine checks | |
318 | * for the caller that there will be enough space to store the data. | |
319 | * It fails if there is not enough space, or if it cannot find | |
320 | * a mbuf to store the address in. | |
321 | * | |
322 | * The higher-level routines sosend and soreceive (in socket.c) | |
b454c3ea | 323 | * also add data to, and remove data from socket buffers repectively. |
4c078bb2 BJ |
324 | */ |
325 | ||
0e18ec4a BJ |
326 | soreserve(so, sndcc, rcvcc) |
327 | struct socket *so; | |
328 | int sndcc, rcvcc; | |
329 | { | |
330 | ||
331 | if (sbreserve(&so->so_snd, sndcc) == 0) | |
332 | goto bad; | |
333 | if (sbreserve(&so->so_rcv, rcvcc) == 0) | |
334 | goto bad2; | |
335 | return (0); | |
336 | bad2: | |
337 | sbrelease(&so->so_snd); | |
338 | bad: | |
339 | return (ENOBUFS); | |
340 | } | |
341 | ||
681ebb17 BJ |
342 | /* |
343 | * Allot mbufs to a sockbuf. | |
344 | */ | |
345 | sbreserve(sb, cc) | |
346 | struct sockbuf *sb; | |
347 | { | |
348 | ||
de48daf3 | 349 | /* someday maybe this routine will fail... */ |
d028a086 | 350 | sb->sb_hiwat = cc; |
5fe6f9d1 | 351 | /* the 2 implies names can be no more than 1 mbuf each */ |
76a6e254 | 352 | sb->sb_mbmax = cc*2; |
ae921915 | 353 | return (1); |
681ebb17 BJ |
354 | } |
355 | ||
356 | /* | |
357 | * Free mbufs held by a socket, and reserved mbuf space. | |
358 | */ | |
359 | sbrelease(sb) | |
360 | struct sockbuf *sb; | |
361 | { | |
362 | ||
363 | sbflush(sb); | |
d028a086 | 364 | sb->sb_hiwat = sb->sb_mbmax = 0; |
681ebb17 BJ |
365 | } |
366 | ||
367 | /* | |
368 | * Routines to add (at the end) and remove (from the beginning) | |
369 | * data from a mbuf queue. | |
370 | */ | |
371 | ||
372 | /* | |
373 | * Append mbuf queue m to sockbuf sb. | |
374 | */ | |
375 | sbappend(sb, m) | |
376 | register struct mbuf *m; | |
377 | register struct sockbuf *sb; | |
378 | { | |
e495e1cc | 379 | register struct mbuf *n; |
681ebb17 | 380 | |
e495e1cc BJ |
381 | n = sb->sb_mb; |
382 | if (n) | |
383 | while (n->m_next) | |
384 | n = n->m_next; | |
681ebb17 | 385 | while (m) { |
a73ab5ae | 386 | if (m->m_len == 0 && (int)m->m_act == 0) { |
c64d826c | 387 | m = m_free(m); |
a73ab5ae BJ |
388 | continue; |
389 | } | |
681ebb17 BJ |
390 | if (n && n->m_off <= MMAXOFF && m->m_off <= MMAXOFF && |
391 | (int)n->m_act == 0 && (int)m->m_act == 0 && | |
76a6e254 BJ |
392 | (n->m_off + n->m_len + m->m_len) <= MMAXOFF) { |
393 | bcopy(mtod(m, caddr_t), mtod(n, caddr_t) + n->m_len, | |
ae921915 | 394 | (unsigned)m->m_len); |
681ebb17 BJ |
395 | n->m_len += m->m_len; |
396 | sb->sb_cc += m->m_len; | |
397 | m = m_free(m); | |
398 | continue; | |
399 | } | |
400 | sballoc(sb, m); | |
e495e1cc BJ |
401 | if (n == 0) |
402 | sb->sb_mb = m; | |
403 | else | |
404 | n->m_next = m; | |
681ebb17 | 405 | n = m; |
681ebb17 | 406 | m = m->m_next; |
e495e1cc | 407 | n->m_next = 0; |
681ebb17 BJ |
408 | } |
409 | } | |
410 | ||
4c078bb2 BJ |
411 | /* |
412 | * Append data and address. | |
413 | * Return 0 if no space in sockbuf or if | |
414 | * can't get mbuf to stuff address in. | |
415 | */ | |
2b4b57cd BJ |
416 | sbappendaddr(sb, asa, m0) |
417 | struct sockbuf *sb; | |
418 | struct sockaddr *asa; | |
419 | struct mbuf *m0; | |
420 | { | |
421 | struct sockaddr *msa; | |
422 | register struct mbuf *m; | |
423 | register int len = sizeof (struct sockaddr); | |
424 | ||
76a6e254 BJ |
425 | m = m0; |
426 | if (m == 0) | |
427 | panic("sbappendaddr"); | |
428 | for (;;) { | |
2b4b57cd | 429 | len += m->m_len; |
76a6e254 BJ |
430 | if (m->m_next == 0) { |
431 | m->m_act = (struct mbuf *)1; | |
432 | break; | |
433 | } | |
434 | m = m->m_next; | |
435 | } | |
509e40dd | 436 | if (len > sbspace(sb)) |
2b4b57cd | 437 | return (0); |
cce93e4b | 438 | m = m_get(M_DONTWAIT, MT_SONAME); |
509e40dd | 439 | if (m == 0) |
2b4b57cd | 440 | return (0); |
2b4b57cd BJ |
441 | m->m_len = sizeof (struct sockaddr); |
442 | msa = mtod(m, struct sockaddr *); | |
443 | *msa = *asa; | |
444 | m->m_act = (struct mbuf *)1; | |
445 | sbappend(sb, m); | |
2b4b57cd BJ |
446 | sbappend(sb, m0); |
447 | return (1); | |
448 | } | |
449 | ||
5fe6f9d1 | 450 | #ifdef notdef |
e435773e BJ |
451 | SBCHECK(sb, str) |
452 | struct sockbuf *sb; | |
453 | char *str; | |
454 | { | |
455 | register int cnt = sb->sb_cc; | |
456 | register int mbcnt = sb->sb_mbcnt; | |
457 | register struct mbuf *m; | |
458 | ||
459 | for (m = sb->sb_mb; m; m = m->m_next) { | |
460 | cnt -= m->m_len; | |
461 | mbcnt -= MSIZE; | |
462 | if (m->m_off > MMAXOFF) | |
463 | mbcnt -= CLBYTES; | |
464 | } | |
465 | if (cnt || mbcnt) { | |
466 | printf("cnt %d mbcnt %d\n", cnt, mbcnt); | |
467 | panic(str); | |
468 | } | |
469 | } | |
5fe6f9d1 | 470 | #endif |
e435773e | 471 | |
681ebb17 BJ |
472 | /* |
473 | * Free all mbufs on a sockbuf mbuf chain. | |
474 | * Check that resource allocations return to 0. | |
475 | */ | |
476 | sbflush(sb) | |
477 | struct sockbuf *sb; | |
478 | { | |
479 | ||
480 | if (sb->sb_flags & SB_LOCK) | |
481 | panic("sbflush"); | |
a73ab5ae BJ |
482 | if (sb->sb_cc) |
483 | sbdrop(sb, sb->sb_cc); | |
681ebb17 BJ |
484 | if (sb->sb_cc || sb->sb_mbcnt || sb->sb_mb) |
485 | panic("sbflush 2"); | |
486 | } | |
487 | ||
488 | /* | |
489 | * Drop data from (the front of) a sockbuf chain. | |
490 | */ | |
491 | sbdrop(sb, len) | |
492 | register struct sockbuf *sb; | |
493 | register int len; | |
494 | { | |
495 | register struct mbuf *m = sb->sb_mb, *mn; | |
496 | ||
497 | while (len > 0) { | |
498 | if (m == 0) | |
499 | panic("sbdrop"); | |
b9f0d37f | 500 | if (m->m_len > len) { |
681ebb17 BJ |
501 | m->m_len -= len; |
502 | m->m_off += len; | |
503 | sb->sb_cc -= len; | |
504 | break; | |
505 | } | |
b9f0d37f BJ |
506 | len -= m->m_len; |
507 | sbfree(sb, m); | |
508 | MFREE(m, mn); | |
509 | m = mn; | |
681ebb17 BJ |
510 | } |
511 | sb->sb_mb = m; | |
512 | } |