1/*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21
22/*
23 * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
24 * Use is subject to license terms.
25 */
26
27#include <sys/types.h>
28#include <inet/ip.h>
29#include <inet/ip_impl.h>
30#include <inet/ipclassifier.h>
31#include <inet/proto_set.h>
32#include <sys/stream.h>
33#include <sys/strsubr.h>
34#include <sys/strsun.h>
35#include <sys/cmn_err.h>
36#include <sys/t_kuser.h>
37#include <sys/tihdr.h>
38#include <sys/pathname.h>
39#include <sys/sockio.h>
40#include <sys/vmem.h>
41#include <sys/disp.h>
42
43void ip_helper_wput(queue_t *q, mblk_t *mp);
44
45static int ip_helper_stream_close(queue_t *, int);
46
47static struct module_info ip_helper_stream_info =  {
48	0, "iphelper", IP_MOD_MINPSZ, IP_MOD_MAXPSZ, IP_MOD_HIWAT, IP_MOD_LOWAT
49};
50
51static struct qinit ip_helper_stream_rinit = {
52	NULL, NULL, NULL, ip_helper_stream_close, NULL,
53	&ip_helper_stream_info, NULL
54};
55
56static struct qinit ip_helper_stream_winit = {
57	(pfi_t)ip_helper_wput, (pfi_t)ip_wsrv, NULL, NULL, NULL,
58	&ip_helper_stream_info, NULL, NULL, NULL, STRUIOT_NONE
59};
60
61/*
62 * set the q_ptr of the 'q' to the conn_t pointer passed in
63 */
64static void
65ip_helper_share_conn(queue_t *q, mblk_t *mp, cred_t *crp)
66{
67	conn_t *connp = *((conn_t **)mp->b_cont->b_rptr);
68
69	/*
70	 * This operation is allowed only on helper streams with kcred
71	 */
72
73	if (kcred != crp || msgdsize(mp->b_cont) != sizeof (void *)) {
74		miocnak(q, mp, 0, EINVAL);
75		return;
76	}
77
78	connp->conn_helper_info->iphs_minfo = q->q_ptr;
79	connp->conn_helper_info->iphs_rq = RD(q);
80	connp->conn_helper_info->iphs_wq = WR(q);
81	WR(q)->q_ptr = RD(q)->q_ptr = (void *)connp;
82	connp->conn_rq = RD(q);
83	connp->conn_wq = WR(q);
84	miocack(q, mp, 0, 0);
85}
86
87void
88ip_helper_wput(queue_t *q, mblk_t *mp)
89{
90	struct iocblk *iocp = (struct iocblk *)mp->b_rptr;
91	if (DB_TYPE(mp) == M_IOCTL &&
92	    iocp->ioc_cmd == SIOCSQPTR) {
93		ip_helper_share_conn(q, mp, iocp->ioc_cr);
94	} else {
95		/* We only handle ioctl related messages here */
96		ASSERT(DB_TYPE(mp) != M_DATA);
97		ip_wput_nondata(q, mp);
98	}
99}
100
101/* ARGSUSED3 */
102int
103ip_helper_stream_setup(queue_t *q, dev_t *devp, int flag, int sflag,
104    cred_t *credp, boolean_t isv6)
105{
106	major_t			maj;
107	ip_helper_minfo_t	*ip_minfop;
108
109	ASSERT((flag & ~(FKLYR)) == IP_HELPER_STR);
110
111	ASSERT(RD(q) == q);
112
113	ip_minfop = kmem_alloc(sizeof (ip_helper_minfo_t), KM_SLEEP);
114	ASSERT(ip_minfop != NULL);
115
116	ip_minfop->ip_minfo_dev = 0;
117	ip_minfop->ip_minfo_arena = NULL;
118
119	/*
120	 * Clone the device, allocate minor device number
121	 */
122	if (ip_minor_arena_la != NULL)
123		ip_minfop->ip_minfo_dev = inet_minor_alloc(ip_minor_arena_la);
124
125	if (ip_minfop->ip_minfo_dev == 0) {
126		/*
127		 * numbers in the large arena are exhausted
128		 * Try small arena.
129		 * Or this is a 32 bit system, 32 bit systems do not have
130		 * ip_minor_arena_la
131		 */
132		ip_minfop->ip_minfo_dev = inet_minor_alloc(ip_minor_arena_sa);
133		if (ip_minfop->ip_minfo_dev == 0) {
134			return (EBUSY);
135		}
136		ip_minfop->ip_minfo_arena = ip_minor_arena_sa;
137	} else {
138		ip_minfop->ip_minfo_arena = ip_minor_arena_la;
139	}
140
141
142	ASSERT(ip_minfop->ip_minfo_dev != 0);
143	ASSERT(ip_minfop->ip_minfo_arena != NULL);
144
145	RD(q)->q_ptr = WR(q)->q_ptr = ip_minfop;
146
147	maj = getemajor(*devp);
148	*devp = makedevice(maj, (ulong_t)(ip_minfop->ip_minfo_dev));
149
150	q->q_qinfo = &ip_helper_stream_rinit;
151	WR(q)->q_qinfo = &ip_helper_stream_winit;
152	qprocson(q);
153	return (0);
154}
155
156/* ARGSUSED1 */
157static int
158ip_helper_stream_close(queue_t *q, int flag)
159{
160	ip_helper_minfo_t *ip_minfop;
161
162	qprocsoff(q);
163	ip_minfop = (q)->q_ptr;
164	inet_minor_free(ip_minfop->ip_minfo_arena,
165	    ip_minfop->ip_minfo_dev);
166	kmem_free(ip_minfop, sizeof (ip_helper_minfo_t));
167	RD(q)->q_ptr = NULL;
168	WR(q)->q_ptr = NULL;
169	return (0);
170}
171
172/*
173 * Public interface for creating an IP stream with shared conn_t
174 * Handles multiple callers in parallel by using conn_lock.
175 * Note that we allocate the helper stream without any locks, which means
176 * we might need to free it if we had two threads doing this concurrently
177 * for the conn_t.
178 */
179int
180ip_create_helper_stream(conn_t *connp, ldi_ident_t li)
181{
182	ip_helper_stream_info_t *helper;
183	int	error;
184	int	ret;
185
186	ASSERT(!servicing_interrupt());
187
188	if (connp->conn_helper_info != NULL) {
189		/* Already allocated */
190		return (0);
191	}
192
193	error = 0;
194	helper = kmem_alloc(sizeof (ip_helper_stream_info_t), KM_SLEEP);
195
196	/*
197	 * open ip device via the layered interface.
198	 * pass in kcred as some threads do not have the
199	 * priviledge to open /dev/ip and the check in
200	 * secpolicy_spec_open() will fail the open
201	 */
202	error = ldi_open_by_name((connp->conn_family == AF_INET6 ? DEV_IP6 :
203	    DEV_IP), IP_HELPER_STR, kcred, &helper->iphs_handle, li);
204
205	if (error != 0) {
206		kmem_free(helper, sizeof (ip_helper_stream_info_t));
207		return (error);
208	}
209	/* Make sure we are the only one */
210	mutex_enter(&connp->conn_lock);
211	if (connp->conn_helper_info != NULL) {
212		/* Some other thread won - discard this stream */
213		mutex_exit(&connp->conn_lock);
214		(void) ldi_close(helper->iphs_handle, 0, kcred);
215		kmem_free(helper, sizeof (ip_helper_stream_info_t));
216		return (0);
217	}
218	connp->conn_helper_info = helper;
219	/*
220	 * Share connp with the helper stream. We hold conn_lock across this
221	 * operation.
222	 */
223	error = ldi_ioctl(helper->iphs_handle, SIOCSQPTR, (intptr_t)connp,
224	    FKIOCTL, kcred, &ret);
225
226	if (error != 0) {
227		/*
228		 * Passing in a zero flag indicates that an error
229		 * occured and stream was not shared
230		 */
231		(void) ldi_close(helper->iphs_handle, 0, kcred);
232		kmem_free(helper, sizeof (ip_helper_stream_info_t));
233		connp->conn_helper_info = NULL;
234	}
235	mutex_exit(&connp->conn_lock);
236	return (error);
237}
238
239/*
240 * Public interface for freeing IP helper stream
241 * Caller must ensure no concurrent use of the conn_t, which is normally
242 * done by calling this from the close routine when the conn_t is quiesced.
243 */
244void
245ip_free_helper_stream(conn_t *connp)
246{
247	ASSERT(!servicing_interrupt());
248
249	if (connp->conn_helper_info == NULL)
250		return;
251
252	ASSERT(connp->conn_helper_info->iphs_handle != NULL);
253
254	connp->conn_helper_info->iphs_rq->q_ptr =
255	    connp->conn_helper_info->iphs_wq->q_ptr =
256	    connp->conn_helper_info->iphs_minfo;
257	(void) ldi_close(connp->conn_helper_info->iphs_handle,
258	    IP_HELPER_STR, kcred);
259	kmem_free(connp->conn_helper_info, sizeof (ip_helper_stream_info_t));
260	connp->conn_helper_info = NULL;
261}
262