1 /*
2 * Copyright (c) 2021-2023 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,
22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23 * Please see the License for the specific language governing rights and
24 * limitations under the License.
25 *
26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27 */
28
29 #include <stdbool.h>
30
31 #include <sys/systm.h>
32 #include <sys/sysctl.h>
33 #include <sys/sbuf.h>
34 #include <sys/types.h>
35 #include <sys/mcache.h>
36 #include <sys/malloc.h>
37
38 #include <os/log.h>
39
40 #include <net/nwk_wq.h>
41 #include <skywalk/lib/net_filter_event.h>
42
43 static uint32_t net_filter_event_state;
44 static bool net_filter_event_initialized;
45 static struct eventhandler_lists_ctxt net_filter_evhdlr_ctxt;
46
47 EVENTHANDLER_DECLARE(net_filter_event, net_filter_event_callback_t);
48
49 static struct sbuf *
net_filter_event_description(uint32_t state)50 net_filter_event_description(uint32_t state)
51 {
52 struct sbuf *sbuf;
53
54 sbuf = sbuf_new(NULL, NULL, 128, SBUF_AUTOEXTEND);
55 if (state & NET_FILTER_EVENT_PF) {
56 sbuf_cat(sbuf, "pf ");
57 }
58 if (state & NET_FILTER_EVENT_SOCKET) {
59 sbuf_cat(sbuf, "socket ");
60 }
61 if (state & NET_FILTER_EVENT_INTERFACE) {
62 sbuf_cat(sbuf, "interface ");
63 }
64 if (state & NET_FILTER_EVENT_IP) {
65 sbuf_cat(sbuf, "ip ");
66 }
67 if (state & NET_FILTER_EVENT_ALF) {
68 sbuf_cat(sbuf, "application-firewall ");
69 }
70 if (state & NET_FILTER_EVENT_PARENTAL_CONTROLS) {
71 sbuf_cat(sbuf, "parental-controls ");
72 }
73 sbuf_trim(sbuf);
74 sbuf_finish(sbuf);
75
76 return sbuf;
77 }
78
79 static void
net_filter_event_callback(struct eventhandler_entry_arg arg0 __unused,enum net_filter_event_subsystems state)80 net_filter_event_callback(struct eventhandler_entry_arg arg0 __unused,
81 enum net_filter_event_subsystems state)
82 {
83 struct sbuf *sbuf = net_filter_event_description(state);
84
85 os_log(OS_LOG_DEFAULT, "net_filter_event: new state (0x%x) %s",
86 state, sbuf_data(sbuf));
87 evhlog(debug, "%s: eventhandler saw event type=net_filter_event_state event_code=%s",
88 __func__, sbuf_data(sbuf));
89 sbuf_delete(sbuf);
90 }
91
92 static void
net_filter_event_init(void)93 net_filter_event_init(void)
94 {
95 if (net_filter_event_initialized) {
96 return;
97 }
98 net_filter_event_initialized = true;
99 eventhandler_lists_ctxt_init(&net_filter_evhdlr_ctxt);
100 net_filter_event_register(net_filter_event_callback);
101 }
102
103 static void
net_filter_event_enqueue_callback(struct nwk_wq_entry * nwk_kwqe)104 net_filter_event_enqueue_callback(struct nwk_wq_entry *nwk_kwqe)
105 {
106 EVENTHANDLER_INVOKE(&net_filter_evhdlr_ctxt, net_filter_event,
107 net_filter_event_state);
108 kfree_type(struct nwk_wq_entry, nwk_kwqe);
109 }
110
111 static void
net_filter_event_enqueue(void)112 net_filter_event_enqueue(void)
113 {
114 struct nwk_wq_entry *__single nwk_wqe;
115
116 struct sbuf *sbuf = net_filter_event_description(net_filter_event_state);
117 evhlog(debug, "%s: eventhandler enqueuing event of type=net_filter_event_state event_code=%s",
118 __func__, sbuf_data(sbuf));
119 sbuf_delete(sbuf);
120
121 nwk_wqe = kalloc_type(struct nwk_wq_entry, Z_WAITOK | Z_ZERO | Z_NOFAIL);
122 nwk_wqe->func = net_filter_event_enqueue_callback;
123 nwk_wq_enqueue(nwk_wqe);
124 }
125
126 void
net_filter_event_mark(enum net_filter_event_subsystems subsystem,bool compatible)127 net_filter_event_mark(enum net_filter_event_subsystems subsystem, bool compatible)
128 {
129 uint32_t old_state = net_filter_event_state;
130
131 net_filter_event_init();
132 if (!compatible) {
133 os_atomic_or(&net_filter_event_state, subsystem, relaxed);
134 } else {
135 os_atomic_andnot(&net_filter_event_state, subsystem, relaxed);
136 }
137 if (old_state != net_filter_event_state) {
138 net_filter_event_enqueue();
139 }
140 }
141
142 enum net_filter_event_subsystems
net_filter_event_get_state(void)143 net_filter_event_get_state(void)
144 {
145 return net_filter_event_state;
146 }
147
148 void
net_filter_event_register(net_filter_event_callback_t callback)149 net_filter_event_register(net_filter_event_callback_t callback)
150 {
151 net_filter_event_init();
152 (void)EVENTHANDLER_REGISTER(&net_filter_evhdlr_ctxt,
153 net_filter_event, callback,
154 eventhandler_entry_dummy_arg,
155 EVENTHANDLER_PRI_ANY);
156 }
157
158 static int
net_filter_event_sysctl(struct sysctl_oid * oidp,void * arg1,int arg2,struct sysctl_req * req)159 net_filter_event_sysctl(struct sysctl_oid *oidp, void *arg1, int arg2,
160 struct sysctl_req *req)
161 {
162 #pragma unused(oidp, arg1, arg2)
163 struct sbuf *sbuf = net_filter_event_description(net_filter_event_state);
164
165 int error = sysctl_io_string(req, sbuf_data(sbuf), 0, 0, NULL);
166 sbuf_delete(sbuf);
167
168 return error;
169 }
170
171 SYSCTL_PROC(_net, OID_AUTO, filter_state,
172 CTLTYPE_STRING | CTLFLAG_LOCKED, NULL, 0,
173 net_filter_event_sysctl, "A", "State of the network filters");
174