xref: /illumos-gate/usr/src/uts/common/inet/iptun/iptun_dev.c (revision 22028508fd28d36ff74dc02c5774a8ba1f0db045)
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  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 /*
27  * IP Tunneling Driver
28  *
29  * As viewed from the top, this module is a GLDv3 driver that consumes the
30  * mac driver interfaces.  It implements the logic for various forms of IP
31  * (IPv4 or IPv6) encapsulation within IP (IPv4 or IPv6).
32  */
33 
34 #include <sys/file.h>
35 #include <sys/list.h>
36 #include "iptun_impl.h"
37 
38 #define	IPTUN_LINKINFO		"IP tunneling driver"
39 #define	IPTUN_HASHSZ		67
40 
41 dev_info_t	*iptun_dip;
42 ldi_ident_t	iptun_ldi_ident;
43 
44 static int	iptun_attach(dev_info_t *, ddi_attach_cmd_t);
45 static int	iptun_detach(dev_info_t *, ddi_detach_cmd_t);
46 static int	iptun_getinfo(dev_info_t *, ddi_info_cmd_t, void *, void **);
47 static int	iptun_constructor(void *, void *, int);
48 static void	iptun_destructor(void *, void *);
49 
50 DDI_DEFINE_STREAM_OPS(iptun_dev_ops, nulldev, nulldev, iptun_attach,
51     iptun_detach, nodev, iptun_getinfo, D_MP, NULL, ddi_quiesce_not_supported);
52 
53 static struct modldrv iptun_modldrv = {
54 	&mod_driverops,
55 	IPTUN_LINKINFO,
56 	&iptun_dev_ops
57 };
58 
59 static struct modlinkage iptun_modlinkage = {
60 	MODREV_1,
61 	&iptun_modldrv,
62 	NULL
63 };
64 
65 /*
66  * Initialize the tunnel stack instance.
67  */
68 /* ARGSUSED */
69 static void *
70 iptun_stack_init(netstackid_t stackid, netstack_t *ns)
71 {
72 	iptun_stack_t	*iptuns;
73 
74 	iptuns = kmem_zalloc(sizeof (*iptuns), KM_SLEEP);
75 	iptuns->iptuns_netstack = ns;
76 	mutex_init(&iptuns->iptuns_lock, NULL, MUTEX_DEFAULT, NULL);
77 	list_create(&iptuns->iptuns_iptunlist, sizeof (iptun_t),
78 	    offsetof(iptun_t, iptun_link));
79 
80 	return (iptuns);
81 }
82 
83 /* ARGSUSED */
84 static void
85 iptun_stack_shutdown(netstackid_t stackid, void *arg)
86 {
87 	iptun_stack_t	*iptuns = arg;
88 	iptun_t		*iptun;
89 	datalink_id_t	linkid;
90 
91 	/* note that iptun_delete() removes iptun from the list */
92 	while ((iptun = list_head(&iptuns->iptuns_iptunlist)) != NULL) {
93 		linkid = iptun->iptun_linkid;
94 		(void) iptun_delete(linkid, iptun->iptun_connp->conn_cred);
95 		(void) dls_mgmt_destroy(linkid, B_FALSE);
96 	}
97 }
98 
99 /*
100  * Free the tunnel stack instance.
101  */
102 /* ARGSUSED */
103 static void
104 iptun_stack_fini(netstackid_t stackid, void *arg)
105 {
106 	iptun_stack_t *iptuns = arg;
107 
108 	list_destroy(&iptuns->iptuns_iptunlist);
109 	mutex_destroy(&iptuns->iptuns_lock);
110 	kmem_free(iptuns, sizeof (*iptuns));
111 }
112 
113 static void
114 iptun_fini(void)
115 {
116 	ddi_taskq_destroy(iptun_taskq);
117 	mac_fini_ops(&iptun_dev_ops);
118 	ldi_ident_release(iptun_ldi_ident);
119 	mod_hash_destroy_idhash(iptun_hash);
120 	kmem_cache_destroy(iptun_cache);
121 }
122 
123 int
124 _init(void)
125 {
126 	int rc;
127 
128 	rc = ldi_ident_from_mod(&iptun_modlinkage, &iptun_ldi_ident);
129 	if (rc != 0)
130 		return (rc);
131 
132 	iptun_cache = kmem_cache_create("iptun_cache", sizeof (iptun_t), 0,
133 	    iptun_constructor, iptun_destructor, NULL, NULL, NULL, 0);
134 	if (iptun_cache == NULL) {
135 		ldi_ident_release(iptun_ldi_ident);
136 		return (ENOMEM);
137 	}
138 
139 	iptun_taskq = ddi_taskq_create(NULL, "iptun_taskq", 1,
140 	    TASKQ_DEFAULTPRI, 0);
141 	if (iptun_taskq == NULL) {
142 		ldi_ident_release(iptun_ldi_ident);
143 		kmem_cache_destroy(iptun_cache);
144 		return (ENOMEM);
145 	}
146 
147 	iptun_hash = mod_hash_create_idhash("iptun_hash", IPTUN_HASHSZ,
148 	    mod_hash_null_valdtor);
149 
150 	mac_init_ops(&iptun_dev_ops, IPTUN_DRIVER_NAME);
151 
152 	if ((rc = mod_install(&iptun_modlinkage)) != 0)
153 		iptun_fini();
154 	return (rc);
155 }
156 
157 int
158 _fini(void)
159 {
160 	int rc;
161 
162 	if ((rc = mod_remove(&iptun_modlinkage)) == 0)
163 		iptun_fini();
164 	return (rc);
165 }
166 
167 int
168 _info(struct modinfo *modinfop)
169 {
170 	return (mod_info(&iptun_modlinkage, modinfop));
171 }
172 
173 static int
174 iptun_attach(dev_info_t *dip, ddi_attach_cmd_t cmd)
175 {
176 	switch (cmd) {
177 	case DDI_ATTACH:
178 		if (ddi_get_instance(dip) != 0 || iptun_ioc_init() != 0)
179 			return (DDI_FAILURE);
180 		iptun_dip = dip;
181 		netstack_register(NS_IPTUN, iptun_stack_init,
182 		    iptun_stack_shutdown, iptun_stack_fini);
183 		return (DDI_SUCCESS);
184 
185 	default:
186 		return (DDI_FAILURE);
187 	}
188 }
189 
190 /* ARGSUSED */
191 static int
192 iptun_detach(dev_info_t *dip, ddi_detach_cmd_t cmd)
193 {
194 	switch (cmd) {
195 	case DDI_DETACH:
196 		/*
197 		 * We prevent the pseudo device from detaching (and thus the
198 		 * driver from unloading) when there are tunnels configured by
199 		 * consulting iptun_count().  We don't need to hold a lock
200 		 * here because the tunnel count is only changed when a tunnel
201 		 * is created or deleted, which can't happen while the detach
202 		 * routine is running (the ioctl path calls
203 		 * ddi_hold_devi_by_instance() in dld's drv_ioctl(), and the
204 		 * /dev/net implicit path has the device open).
205 		 */
206 		if (iptun_count() > 0)
207 			return (DDI_FAILURE);
208 		netstack_unregister(NS_IPTUN);
209 		iptun_dip = NULL;
210 		iptun_ioc_fini();
211 		return (DDI_SUCCESS);
212 
213 	default:
214 		return (DDI_FAILURE);
215 	}
216 }
217 
218 /* ARGSUSED */
219 static int
220 iptun_getinfo(dev_info_t *dip, ddi_info_cmd_t infocmd, void *arg, void **result)
221 {
222 	switch (infocmd) {
223 	case DDI_INFO_DEVT2DEVINFO:
224 		*result = iptun_dip;
225 		return (DDI_SUCCESS);
226 	case DDI_INFO_DEVT2INSTANCE:
227 		*result = NULL;
228 		return (DDI_SUCCESS);
229 	}
230 	return (DDI_FAILURE);
231 }
232 
233 /* ARGSUSED */
234 static int
235 iptun_constructor(void *buf, void *cdrarg, int kmflags)
236 {
237 	iptun_t	*iptun = buf;
238 
239 	bzero(iptun, sizeof (*iptun));
240 	mutex_init(&iptun->iptun_lock, NULL, MUTEX_DEFAULT, NULL);
241 	cv_init(&iptun->iptun_upcall_cv, NULL, CV_DRIVER, NULL);
242 	cv_init(&iptun->iptun_enter_cv, NULL, CV_DRIVER, NULL);
243 
244 	return (0);
245 }
246 
247 /* ARGSUSED */
248 static void
249 iptun_destructor(void *buf, void *cdrarg)
250 {
251 	iptun_t *iptun = buf;
252 
253 	/* This iptun_t must not still be in use. */
254 	ASSERT(!(iptun->iptun_flags & (IPTUN_BOUND|IPTUN_MAC_REGISTERED|
255 	    IPTUN_MAC_STARTED|IPTUN_HASH_INSERTED|IPTUN_UPCALL_PENDING)));
256 
257 	mutex_destroy(&iptun->iptun_lock);
258 	cv_destroy(&iptun->iptun_upcall_cv);
259 }
260