| 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 |
| 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(port_store: sessionport, |
| 62 | kobject: aia_p, type: IKOT_AU_SESSIONPORT, alloc_opts: 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 * |
| 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, type: 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 |
| 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, type: 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 |
| 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, mscount: 0, type: 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 | |