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 (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
23 */
24
25 #include <sys/sysmacros.h>
26 #include <sys/atomic.h>
27 #include <sys/strsubr.h>
28 #include <sys/socket.h>
29 #include <sys/socketvar.h>
30 #include <sys/cmn_err.h>
31 #include <sys/modctl.h>
32 #include <sys/sdt.h>
33
34 list_t smod_list;
35 kmutex_t smod_list_lock;
36
37 so_create_func_t sock_comm_create_function;
38 so_destroy_func_t sock_comm_destroy_function;
39
40 static smod_info_t *smod_create(const char *);
41 static void smod_destroy(smod_info_t *);
42
43 extern void smod_add(smod_info_t *);
44
45 void
smod_init(void)46 smod_init(void)
47 {
48 list_create(&smod_list, sizeof (smod_info_t),
49 offsetof(smod_info_t, smod_node));
50 mutex_init(&smod_list_lock, NULL, MUTEX_DEFAULT, NULL);
51 }
52
53 static smod_info_t *
smod_find(const char * modname)54 smod_find(const char *modname)
55 {
56 smod_info_t *smodp;
57
58 ASSERT(MUTEX_HELD(&smod_list_lock));
59
60 for (smodp = list_head(&smod_list); smodp != NULL;
61 smodp = list_next(&smod_list, smodp))
62 if (strcmp(smodp->smod_name, modname) == 0)
63 return (smodp);
64 return (NULL);
65 }
66
67 /*
68 * Register the socket module.
69 */
70 int
smod_register(const smod_reg_t * reg)71 smod_register(const smod_reg_t *reg)
72 {
73 smod_info_t *smodp;
74
75 /*
76 * Make sure the socket module does not depend on capabilities
77 * not available on the system.
78 */
79 if (reg->smod_version != SOCKMOD_VERSION ||
80 reg->smod_dc_version != SOCK_DC_VERSION ||
81 reg->smod_uc_version != SOCK_UC_VERSION) {
82 cmn_err(CE_WARN,
83 "Failed to register socket module %s: version mismatch",
84 reg->smod_name);
85 return (EINVAL);
86 }
87
88 #ifdef DEBUG
89 mutex_enter(&smod_list_lock);
90 if ((smodp = smod_find(reg->smod_name)) != NULL) {
91 mutex_exit(&smod_list_lock);
92 return (EEXIST);
93 }
94 mutex_exit(&smod_list_lock);
95 #endif
96
97 smodp = smod_create(reg->smod_name);
98 smodp->smod_version = reg->smod_version;
99 if (strcmp(smodp->smod_name, SOTPI_SMOD_NAME) == 0 ||
100 strcmp(smodp->smod_name, "socksctp") == 0 ||
101 strcmp(smodp->smod_name, "socksdp") == 0) {
102 ASSERT(smodp->smod_proto_create_func == NULL);
103 ASSERT(reg->__smod_priv != NULL);
104 smodp->smod_sock_create_func =
105 reg->__smod_priv->smodp_sock_create_func;
106 smodp->smod_sock_destroy_func =
107 reg->__smod_priv->smodp_sock_destroy_func;
108 smodp->smod_proto_create_func = NULL;
109 } else {
110 if (reg->smod_proto_create_func == NULL ||
111 (reg->__smod_priv != NULL &&
112 (reg->__smod_priv->smodp_sock_create_func != NULL ||
113 reg->__smod_priv->smodp_sock_destroy_func != NULL))) {
114 #ifdef DEBUG
115 cmn_err(CE_CONT, "smod_register of %s failed",
116 smodp->smod_name);
117 #endif
118 smod_destroy(smodp);
119 return (EINVAL);
120 }
121 smodp->smod_proto_create_func = reg->smod_proto_create_func;
122 smodp->smod_sock_create_func = sock_comm_create_function;
123 smodp->smod_sock_destroy_func = sock_comm_destroy_function;
124 smodp->smod_uc_version = reg->smod_uc_version;
125 smodp->smod_dc_version = reg->smod_dc_version;
126 if (reg->__smod_priv != NULL) {
127 smodp->smod_proto_fallback_func =
128 reg->__smod_priv->smodp_proto_fallback_func;
129 smodp->smod_fallback_devpath_v4 =
130 reg->__smod_priv->smodp_fallback_devpath_v4;
131 smodp->smod_fallback_devpath_v6 =
132 reg->__smod_priv->smodp_fallback_devpath_v6;
133 }
134 }
135 smod_add(smodp);
136 return (0);
137 }
138
139 /*
140 * Unregister the socket module
141 */
142 int
smod_unregister(const char * mod_name)143 smod_unregister(const char *mod_name)
144 {
145 smod_info_t *smodp;
146
147 mutex_enter(&smod_list_lock);
148 if ((smodp = smod_find(mod_name)) != NULL) {
149 if (smodp->smod_refcnt != 0) {
150 mutex_exit(&smod_list_lock);
151 return (EBUSY);
152 } else {
153 /*
154 * Delete the entry from the socket module list.
155 */
156 list_remove(&smod_list, smodp);
157 mutex_exit(&smod_list_lock);
158
159 smod_destroy(smodp);
160 return (0);
161 }
162 }
163 mutex_exit(&smod_list_lock);
164
165 return (ENXIO);
166 }
167
168 /*
169 * Initialize the socket module entry.
170 */
171 static smod_info_t *
smod_create(const char * modname)172 smod_create(const char *modname)
173 {
174 smod_info_t *smodp;
175 int len;
176
177 smodp = kmem_zalloc(sizeof (*smodp), KM_SLEEP);
178 len = strlen(modname) + 1;
179 smodp->smod_name = kmem_alloc(len, KM_SLEEP);
180 bcopy(modname, smodp->smod_name, len);
181 smodp->smod_name[len - 1] = '\0';
182 return (smodp);
183 }
184
185 /*
186 * Clean up the socket module part of the sockparams entry.
187 */
188 static void
smod_destroy(smod_info_t * smodp)189 smod_destroy(smod_info_t *smodp)
190 {
191 ASSERT(smodp->smod_name != NULL);
192 ASSERT(smodp->smod_refcnt == 0);
193 ASSERT(!list_link_active(&smodp->smod_node));
194 ASSERT(strcmp(smodp->smod_name, "socktpi") != 0);
195
196 kmem_free(smodp->smod_name, strlen(smodp->smod_name) + 1);
197 smodp->smod_name = NULL;
198 smodp->smod_proto_create_func = NULL;
199 smodp->smod_sock_create_func = NULL;
200 smodp->smod_sock_destroy_func = NULL;
201 kmem_free(smodp, sizeof (*smodp));
202 }
203
204 /*
205 * Add an entry at the front of the socket module list.
206 */
207 void
smod_add(smod_info_t * smodp)208 smod_add(smod_info_t *smodp)
209 {
210 ASSERT(smodp != NULL);
211 mutex_enter(&smod_list_lock);
212 list_insert_head(&smod_list, smodp);
213 mutex_exit(&smod_list_lock);
214 }
215
216 /*
217 * Lookup the socket module table by the socket module name.
218 * If there is an existing entry, then increase the reference count.
219 * Otherwise we load the module and in the module register function create
220 * a new entry and add it to the end of the socket module table.
221 */
222 smod_info_t *
smod_lookup_byname(const char * modname)223 smod_lookup_byname(const char *modname)
224 {
225 smod_info_t *smodp;
226 int error;
227
228 again:
229 /*
230 * If find an entry, increase the reference count and
231 * return the entry pointer.
232 */
233 mutex_enter(&smod_list_lock);
234 if ((smodp = smod_find(modname)) != NULL) {
235 SMOD_INC_REF(smodp);
236 mutex_exit(&smod_list_lock);
237 return (smodp);
238 }
239 mutex_exit(&smod_list_lock);
240
241 /*
242 * We have a sockmod, and it is not loaded.
243 * Load the module into the kernel, modload() will
244 * take care of the multiple threads.
245 */
246 DTRACE_PROBE1(load__socket__module, char *, modname);
247 error = modload(SOCKMOD_PATH, modname);
248 if (error == -1) {
249 cmn_err(CE_CONT, "modload of %s/%s failed",
250 SOCKMOD_PATH, modname);
251 return (NULL);
252 }
253 goto again;
254 }
255