xref: /xnu-10002.61.3/bsd/netinet/mp_pcb.c (revision 0f4c859e951fba394238ab619495c4e1d54d0f34)
1 /*
2  * Copyright (c) 2012-2017 Apple Inc. All rights reserved.
3  *
4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5  *
6  * This file contains Original Code and/or Modifications of Original Code
7  * as defined in and that are subject to the Apple Public Source License
8  * Version 2.0 (the 'License'). You may not use this file except in
9  * compliance with the License. The rights granted to you under the License
10  * may not be used to create, or enable the creation or redistribution of,
11  * unlawful or unlicensed copies of an Apple operating system, or to
12  * circumvent, violate, or enable the circumvention or violation of, any
13  * terms of an Apple operating system software license agreement.
14  *
15  * Please obtain a copy of the License at
16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
17  *
18  * The Original Code and all software distributed under the License are
19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
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23  * Please see the License for the specific language governing rights and
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26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27  */
28 
29 #include <sys/param.h>
30 #include <sys/systm.h>
31 #include <sys/kernel.h>
32 #include <sys/mbuf.h>
33 #include <sys/mcache.h>
34 #include <sys/syslog.h>
35 #include <sys/socket.h>
36 #include <sys/socketvar.h>
37 #include <sys/protosw.h>
38 #include <sys/proc_internal.h>
39 
40 #include <mach/boolean.h>
41 #include <kern/zalloc.h>
42 #include <kern/locks.h>
43 
44 #include <netinet/mp_pcb.h>
45 #include <netinet/mptcp_var.h>
46 #include <netinet6/in6_pcb.h>
47 
48 static LCK_GRP_DECLARE(mp_lock_grp, "multipath");
49 static LCK_ATTR_DECLARE(mp_lock_attr, 0, 0);
50 static LCK_MTX_DECLARE_ATTR(mp_lock, &mp_lock_grp, &mp_lock_attr);
51 static LCK_MTX_DECLARE_ATTR(mp_timeout_lock, &mp_lock_grp, &mp_lock_attr);
52 
53 static TAILQ_HEAD(, mppcbinfo) mppi_head = TAILQ_HEAD_INITIALIZER(mppi_head);
54 
55 static boolean_t mp_timeout_run;        /* MP timer is scheduled to run */
56 static boolean_t mp_garbage_collecting;
57 static boolean_t mp_ticking;
58 static void mp_sched_timeout(void);
59 static void mp_timeout(void *);
60 
61 static void
mpp_lock_assert_held(struct mppcb * mp)62 mpp_lock_assert_held(struct mppcb *mp)
63 {
64 #if !MACH_ASSERT
65 #pragma unused(mp)
66 #endif
67 	LCK_MTX_ASSERT(&mp->mpp_lock, LCK_MTX_ASSERT_OWNED);
68 }
69 
70 static void
mp_timeout(void * arg)71 mp_timeout(void *arg)
72 {
73 #pragma unused(arg)
74 	struct mppcbinfo *mppi;
75 	boolean_t t, gc;
76 	uint32_t t_act = 0;
77 	uint32_t gc_act = 0;
78 
79 	/*
80 	 * Update coarse-grained networking timestamp (in sec.); the idea
81 	 * is to piggy-back on the timeout callout to update the counter
82 	 * returnable via net_uptime().
83 	 */
84 	net_update_uptime();
85 
86 	lck_mtx_lock_spin(&mp_timeout_lock);
87 	gc = mp_garbage_collecting;
88 	mp_garbage_collecting = FALSE;
89 
90 	t = mp_ticking;
91 	mp_ticking = FALSE;
92 
93 	if (gc || t) {
94 		lck_mtx_unlock(&mp_timeout_lock);
95 
96 		lck_mtx_lock(&mp_lock);
97 		TAILQ_FOREACH(mppi, &mppi_head, mppi_entry) {
98 			if ((gc && mppi->mppi_gc != NULL) ||
99 			    (t && mppi->mppi_timer != NULL)) {
100 				lck_mtx_lock(&mppi->mppi_lock);
101 				if (gc && mppi->mppi_gc != NULL) {
102 					gc_act += mppi->mppi_gc(mppi);
103 				}
104 				if (t && mppi->mppi_timer != NULL) {
105 					t_act += mppi->mppi_timer(mppi);
106 				}
107 				lck_mtx_unlock(&mppi->mppi_lock);
108 			}
109 		}
110 		lck_mtx_unlock(&mp_lock);
111 
112 		lck_mtx_lock_spin(&mp_timeout_lock);
113 	}
114 
115 	/* lock was dropped above, so check first before overriding */
116 	if (!mp_garbage_collecting) {
117 		mp_garbage_collecting = (gc_act != 0);
118 	}
119 	if (!mp_ticking) {
120 		mp_ticking = (t_act != 0);
121 	}
122 
123 	/* re-arm the timer if there's work to do */
124 	mp_timeout_run = FALSE;
125 	mp_sched_timeout();
126 	lck_mtx_unlock(&mp_timeout_lock);
127 }
128 
129 static void
mp_sched_timeout(void)130 mp_sched_timeout(void)
131 {
132 	LCK_MTX_ASSERT(&mp_timeout_lock, LCK_MTX_ASSERT_OWNED);
133 
134 	if (!mp_timeout_run && (mp_garbage_collecting || mp_ticking)) {
135 		lck_mtx_convert_spin(&mp_timeout_lock);
136 		mp_timeout_run = TRUE;
137 		timeout(mp_timeout, NULL, hz);
138 	}
139 }
140 
141 void
mp_gc_sched(void)142 mp_gc_sched(void)
143 {
144 	lck_mtx_lock_spin(&mp_timeout_lock);
145 	mp_garbage_collecting = TRUE;
146 	mp_sched_timeout();
147 	lck_mtx_unlock(&mp_timeout_lock);
148 }
149 
150 void
mptcp_timer_sched(void)151 mptcp_timer_sched(void)
152 {
153 	lck_mtx_lock_spin(&mp_timeout_lock);
154 	mp_ticking = TRUE;
155 	mp_sched_timeout();
156 	lck_mtx_unlock(&mp_timeout_lock);
157 }
158 
159 void
mp_pcbinfo_attach(struct mppcbinfo * mppi)160 mp_pcbinfo_attach(struct mppcbinfo *mppi)
161 {
162 	struct mppcbinfo *mppi0;
163 
164 	lck_mtx_lock(&mp_lock);
165 	TAILQ_FOREACH(mppi0, &mppi_head, mppi_entry) {
166 		if (mppi0 == mppi) {
167 			panic("%s: mppi %p already in the list",
168 			    __func__, mppi);
169 			/* NOTREACHED */
170 		}
171 	}
172 	TAILQ_INSERT_TAIL(&mppi_head, mppi, mppi_entry);
173 	lck_mtx_unlock(&mp_lock);
174 }
175 
176 int
mp_pcbinfo_detach(struct mppcbinfo * mppi)177 mp_pcbinfo_detach(struct mppcbinfo *mppi)
178 {
179 	struct mppcbinfo *mppi0;
180 	int error = 0;
181 
182 	lck_mtx_lock(&mp_lock);
183 	TAILQ_FOREACH(mppi0, &mppi_head, mppi_entry) {
184 		if (mppi0 == mppi) {
185 			break;
186 		}
187 	}
188 	if (mppi0 != NULL) {
189 		TAILQ_REMOVE(&mppi_head, mppi0, mppi_entry);
190 	} else {
191 		error = ENXIO;
192 	}
193 	lck_mtx_unlock(&mp_lock);
194 
195 	return error;
196 }
197 
198 int
mp_pcballoc(struct socket * so,struct mppcbinfo * mppi)199 mp_pcballoc(struct socket *so, struct mppcbinfo *mppi)
200 {
201 	struct mppcb *mpp = NULL;
202 	int error;
203 
204 	VERIFY(mpsotomppcb(so) == NULL);
205 
206 	mpp = mppi->mppi_alloc();
207 	lck_mtx_init(&mpp->mpp_lock, mppi->mppi_lock_grp, &mppi->mppi_lock_attr);
208 	mpp->mpp_pcbinfo = mppi;
209 	mpp->mpp_state = MPPCB_STATE_INUSE;
210 	mpp->mpp_socket = so;
211 	so->so_pcb = mpp;
212 
213 	error = mptcp_session_create(mpp);
214 	if (error) {
215 		lck_mtx_destroy(&mpp->mpp_lock, mppi->mppi_lock_grp);
216 		mppi->mppi_free(mpp);
217 		return error;
218 	}
219 
220 	lck_mtx_lock(&mppi->mppi_lock);
221 	mpp->mpp_flags |= MPP_ATTACHED;
222 	TAILQ_INSERT_TAIL(&mppi->mppi_pcbs, mpp, mpp_entry);
223 	mppi->mppi_count++;
224 
225 	lck_mtx_unlock(&mppi->mppi_lock);
226 
227 	return 0;
228 }
229 
230 void
mp_pcbdetach(struct socket * mp_so)231 mp_pcbdetach(struct socket *mp_so)
232 {
233 	struct mppcb *mpp = mpsotomppcb(mp_so);
234 
235 	mpp->mpp_state = MPPCB_STATE_DEAD;
236 
237 	mp_gc_sched();
238 }
239 
240 void
mptcp_pcbdispose(struct mppcb * mpp)241 mptcp_pcbdispose(struct mppcb *mpp)
242 {
243 	struct mppcbinfo *mppi = mpp->mpp_pcbinfo;
244 	struct socket *mp_so = mpp->mpp_socket;
245 
246 	VERIFY(mppi != NULL);
247 
248 	LCK_MTX_ASSERT(&mppi->mppi_lock, LCK_MTX_ASSERT_OWNED);
249 	mpp_lock_assert_held(mpp);
250 
251 	VERIFY(mpp->mpp_state == MPPCB_STATE_DEAD);
252 	VERIFY(mpp->mpp_flags & MPP_ATTACHED);
253 
254 	mpp->mpp_flags &= ~MPP_ATTACHED;
255 	TAILQ_REMOVE(&mppi->mppi_pcbs, mpp, mpp_entry);
256 	VERIFY(mppi->mppi_count != 0);
257 	mppi->mppi_count--;
258 
259 	if (mppi->mppi_count == 0) {
260 		if (mptcp_cellicon_refcount) {
261 			os_log_error(mptcp_log_handle, "%s: No more MPTCP-flows, but cell icon counter is %u\n",
262 			    __func__, mptcp_cellicon_refcount);
263 			mptcp_clear_cellicon();
264 			mptcp_cellicon_refcount = 0;
265 		}
266 	}
267 
268 	VERIFY(mpp->mpp_inside == 0);
269 	mpp_unlock(mpp);
270 
271 #if NECP
272 	necp_mppcb_dispose(mpp);
273 #endif /* NECP */
274 
275 	sofreelastref(mp_so, 0);
276 	if (mp_so->so_rcv.sb_cc > 0 || mp_so->so_snd.sb_cc > 0) {
277 		/*
278 		 * selthreadclear() already called
279 		 * during sofreelastref() above.
280 		 */
281 		sbrelease(&mp_so->so_rcv);
282 		sbrelease(&mp_so->so_snd);
283 	}
284 
285 	lck_mtx_destroy(&mpp->mpp_lock, mppi->mppi_lock_grp);
286 
287 	VERIFY(mpp->mpp_socket != NULL);
288 	VERIFY(mpp->mpp_socket->so_usecount == 0);
289 	mpp->mpp_socket->so_pcb = NULL;
290 	mpp->mpp_socket = NULL;
291 	mppi->mppi_free(mpp);
292 }
293 
294 static int
mp_getaddr_v4(struct socket * mp_so,struct sockaddr ** nam,boolean_t peer)295 mp_getaddr_v4(struct socket *mp_so, struct sockaddr **nam, boolean_t peer)
296 {
297 	struct mptses *mpte = mpsotompte(mp_so);
298 	struct sockaddr_in *sin;
299 
300 	/*
301 	 * Do the malloc first in case it blocks.
302 	 */
303 	sin = (struct sockaddr_in *)alloc_sockaddr(sizeof(*sin),
304 	    Z_WAITOK | Z_NOFAIL);
305 
306 	sin->sin_family = AF_INET;
307 
308 	if (!peer) {
309 		sin->sin_port = mpte->__mpte_src_v4.sin_port;
310 		sin->sin_addr = mpte->__mpte_src_v4.sin_addr;
311 	} else {
312 		sin->sin_port = mpte->__mpte_dst_v4.sin_port;
313 		sin->sin_addr = mpte->__mpte_dst_v4.sin_addr;
314 	}
315 
316 	*nam = (struct sockaddr *)sin;
317 	return 0;
318 }
319 
320 static int
mp_getaddr_v6(struct socket * mp_so,struct sockaddr ** nam,boolean_t peer)321 mp_getaddr_v6(struct socket *mp_so, struct sockaddr **nam, boolean_t peer)
322 {
323 	struct mptses *mpte = mpsotompte(mp_so);
324 	struct in6_addr addr;
325 	in_port_t port;
326 	uint32_t ifscope;
327 
328 	if (!peer) {
329 		port = mpte->__mpte_src_v6.sin6_port;
330 		addr = mpte->__mpte_src_v6.sin6_addr;
331 		ifscope = mpte->__mpte_src_v6.sin6_scope_id;
332 	} else {
333 		port = mpte->__mpte_dst_v6.sin6_port;
334 		addr = mpte->__mpte_dst_v6.sin6_addr;
335 		ifscope = mpte->__mpte_dst_v6.sin6_scope_id;
336 	}
337 
338 	*nam = in6_sockaddr(port, &addr, ifscope);
339 	if (*nam == NULL) {
340 		return ENOBUFS;
341 	}
342 
343 	return 0;
344 }
345 
346 int
mp_getsockaddr(struct socket * mp_so,struct sockaddr ** nam)347 mp_getsockaddr(struct socket *mp_so, struct sockaddr **nam)
348 {
349 	struct mptses *mpte = mpsotompte(mp_so);
350 
351 	if (mpte->mpte_src.sa_family == AF_INET || mpte->mpte_src.sa_family == 0) {
352 		return mp_getaddr_v4(mp_so, nam, false);
353 	} else if (mpte->mpte_src.sa_family == AF_INET6) {
354 		return mp_getaddr_v6(mp_so, nam, false);
355 	} else {
356 		return EINVAL;
357 	}
358 }
359 
360 int
mp_getpeeraddr(struct socket * mp_so,struct sockaddr ** nam)361 mp_getpeeraddr(struct socket *mp_so, struct sockaddr **nam)
362 {
363 	struct mptses *mpte = mpsotompte(mp_so);
364 
365 	if (mpte->mpte_src.sa_family == AF_INET || mpte->mpte_src.sa_family == 0) {
366 		return mp_getaddr_v4(mp_so, nam, true);
367 	} else if (mpte->mpte_src.sa_family == AF_INET6) {
368 		return mp_getaddr_v6(mp_so, nam, true);
369 	} else {
370 		return EINVAL;
371 	}
372 }
373