1 /*
2 * Copyright (c) 2008 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 #include <mach/mach_types.h>
29 #include <mach/notify.h>
30 #include <ipc/ipc_port.h>
31 #include <kern/ipc_kobject.h>
32 #include <kern/audit_sessionport.h>
33 #include <libkern/OSAtomic.h>
34
35 #if CONFIG_AUDIT
36 /*
37 * audit_session_mksend
38 *
39 * Description: Obtain a send right for given audit session.
40 *
41 * Parameters: *aia_p Audit session information to assosiate with
42 * the new port.
43 * *sessionport Pointer to the current session port. This may
44 * actually be set to IPC_PORT_NULL.
45 *
46 * Returns: !NULL Resulting send right.
47 * NULL Failed to allocate port (due to lack of memory
48 * resources).
49 *
50 * Assumptions: Caller holds a reference on the session during the call.
51 * If there were no outstanding send rights against the port,
52 * hold a reference on the session and arm a new no-senders
53 * notification to determine when to release that reference.
54 * Otherwise, by creating an additional send right, we share
55 * the port's reference until all send rights go away.
56 */
57 ipc_port_t
audit_session_mksend(struct auditinfo_addr * aia_p,ipc_port_t * sessionport)58 audit_session_mksend(struct auditinfo_addr *aia_p, ipc_port_t *sessionport)
59 {
60 audit_session_aiaref(aia_p);
61 if (!ipc_kobject_make_send_lazy_alloc_port(sessionport,
62 aia_p, IKOT_AU_SESSIONPORT, IPC_KOBJECT_ALLOC_NONE)) {
63 audit_session_aiaunref(aia_p);
64 }
65
66 return *sessionport;
67 }
68
69
70 /*
71 * audit_session_porttoaia
72 *
73 * Description: Obtain the audit session info associated with the given port.
74 *
75 * Parameters: port A Mach port.
76 *
77 * Returns: NULL The given Mach port did not reference audit
78 * session info.
79 * !NULL The audit session info that is associated with
80 * the Mach port.
81 *
82 * Notes: The caller must hold an outstanding send-right on the sessionport.
83 */
84 struct auditinfo_addr *
audit_session_porttoaia(ipc_port_t port)85 audit_session_porttoaia(ipc_port_t port)
86 {
87 struct auditinfo_addr *aia_p = NULL;
88
89 if (IP_VALID(port)) {
90 aia_p = ipc_kobject_get_stable(port, IKOT_AU_SESSIONPORT);
91 }
92
93 return aia_p;
94 }
95
96
97 /*
98 * audit_session_no_senders
99 *
100 * Description: Handle a no-senders notification for a sessionport.
101 *
102 * Notes: It is possible that new send rights are created after a
103 * no-senders notification has been sent, but they will be protected
104 * by another aia reference.
105 */
106 static void
audit_session_no_senders(ipc_port_t port,__unused mach_port_mscount_t mscount)107 audit_session_no_senders(ipc_port_t port, __unused mach_port_mscount_t mscount)
108 {
109 struct auditinfo_addr *aia_p = NULL;
110
111 aia_p = ipc_kobject_get_stable(port, IKOT_AU_SESSIONPORT);
112 assert(NULL != aia_p);
113
114 audit_session_aiaunref(aia_p);
115 }
116
117 /*
118 * audit_session_portdestroy
119 *
120 * Description: Destroy the kobject associated with the audit_session
121 *
122 * Notes: It is called when there is no outstanding references on the aia
123 * anymore (it also won't have any outstanding send rights)
124 */
125 void
audit_session_portdestroy(ipc_port_t * sessionport)126 audit_session_portdestroy(ipc_port_t *sessionport)
127 {
128 ipc_port_t port = *sessionport;
129
130 *sessionport = IP_NULL;
131 if (IP_VALID(port)) {
132 ipc_kobject_dealloc_port(port, 0, IKOT_AU_SESSIONPORT);
133 }
134 }
135
136 IPC_KOBJECT_DEFINE(IKOT_AU_SESSIONPORT,
137 .iko_op_stable = true,
138 .iko_op_no_senders = audit_session_no_senders);
139
140 #endif /* CONFIG_AUDIT */
141