1 | /* |
2 | * Copyright (c) 2003,2008,2017 Apple Computer, 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 | * @header kpi_interfacefilter.h |
30 | * This header defines an API to attach interface filters. Interface |
31 | * filters may be attached to a specific interface. The filters can |
32 | * intercept all packets in to and out of the specific interface. In |
33 | * addition, the filters may intercept interface specific events and |
34 | * ioctls. |
35 | */ |
36 | |
37 | #ifndef __KPI_INTERFACEFILTER__ |
38 | #define __KPI_INTERFACEFILTER__ |
39 | #include <sys/kernel_types.h> |
40 | #include <net/kpi_interface.h> |
41 | |
42 | #ifndef PRIVATE |
43 | #include <Availability.h> |
44 | #define __NKE_API_DEPRECATED __API_DEPRECATED("Network Kernel Extension KPI is deprecated", macos(10.4, 10.15.4)) |
45 | #else |
46 | #define __NKE_API_DEPRECATED |
47 | #endif /* PRIVATE */ |
48 | |
49 | struct kev_msg; |
50 | |
51 | __BEGIN_DECLS |
52 | |
53 | /*! |
54 | * @typedef iff_input_func |
55 | * |
56 | * @discussion iff_input_func is used to filter incoming packets. The |
57 | * interface is only valid for the duration of the filter call. If |
58 | * you need to keep a reference to the interface, be sure to call |
59 | * ifnet_reference and ifnet_release. The packets passed to the |
60 | * inbound filter are different from those passed to the outbound |
61 | * filter. Packets to the inbound filter have the frame header |
62 | * passed in separately from the rest of the packet. The outbound |
63 | * data filters is passed the whole packet including the frame |
64 | * header. |
65 | * |
66 | * The frame header usually preceeds the data in the mbuf. This |
67 | * ensures that the frame header will be a valid pointer as long as |
68 | * the mbuf is not freed. If you need to change the frame header to |
69 | * point somewhere else, the recommended method is to prepend a new |
70 | * frame header to the mbuf chain (mbuf_prepend), set the header to |
71 | * point to that data, then call mbuf_adj to move the mbuf data |
72 | * pointer back to the start of the packet payload. |
73 | * @param cookie The cookie specified when this filter was attached. |
74 | * @param interface The interface the packet was recieved on. |
75 | * @param protocol The protocol of this packet. If you specified a |
76 | * protocol when attaching your filter, the protocol will only ever |
77 | * be the protocol you specified. |
78 | * @param data The inbound packet, after the frame header as determined |
79 | * by the interface. |
80 | * @param frame_ptr A pointer to the pointer to the frame header. The |
81 | * frame header length can be found by inspecting the interface's |
82 | * frame header length (ifnet_hdrlen). |
83 | * @result Return: |
84 | * 0 - The caller will continue with normal processing of the |
85 | * packet. |
86 | * EJUSTRETURN - The caller will stop processing the packet, |
87 | * the packet will not be freed. |
88 | * Anything Else - The caller will free the packet and stop |
89 | * processing. |
90 | */ |
91 | typedef errno_t (*iff_input_func)(void *cookie, ifnet_t interface, |
92 | protocol_family_t protocol, mbuf_t *data, char **frame_ptr); |
93 | |
94 | /*! |
95 | * @typedef iff_output_func |
96 | * |
97 | * @discussion iff_output_func is used to filter fully formed outbound |
98 | * packets. The interface is only valid for the duration of the |
99 | * filter call. If you need to keep a reference to the interface, |
100 | * be sure to call ifnet_reference and ifnet_release. |
101 | * @param cookie The cookie specified when this filter was attached. |
102 | * @param interface The interface the packet is being transmitted on. |
103 | * @param data The fully formed outbound packet in a chain of mbufs. |
104 | * The frame header is already included. The filter function may |
105 | * modify the packet or return a different mbuf chain. |
106 | * @result Return: |
107 | * 0 - The caller will continue with normal processing of the |
108 | * packet. |
109 | * EJUSTRETURN - The caller will stop processing the packet, |
110 | * the packet will not be freed. |
111 | * Anything Else - The caller will free the packet and stop |
112 | * processing. |
113 | */ |
114 | typedef errno_t (*iff_output_func)(void *cookie, ifnet_t interface, |
115 | protocol_family_t protocol, mbuf_t *data); |
116 | |
117 | /*! |
118 | * @typedef iff_event_func |
119 | * |
120 | * @discussion iff_event_func is used to filter interface specific |
121 | * events. The interface is only valid for the duration of the |
122 | * filter call. If you need to keep a reference to the interface, |
123 | * be sure to call ifnet_reference and ifnet_release. |
124 | * @param cookie The cookie specified when this filter was attached. |
125 | * @param interface The interface the packet is being transmitted on. |
126 | * @param event_msg The kernel event, may not be changed. |
127 | */ |
128 | typedef void (*iff_event_func)(void *cookie, ifnet_t interface, |
129 | protocol_family_t protocol, const struct kev_msg *event_msg); |
130 | |
131 | /*! |
132 | * @typedef iff_ioctl_func |
133 | * |
134 | * @discussion iff_ioctl_func is used to filter ioctls sent to an |
135 | * interface. The interface is only valid for the duration of the |
136 | * filter call. If you need to keep a reference to the interface, |
137 | * be sure to call ifnet_reference and ifnet_release. |
138 | * |
139 | * All undefined ioctls are reserved for future use by Apple. If |
140 | * you need to communicate with your kext using an ioctl, please |
141 | * use SIOCSIFKPI and SIOCGIFKPI. |
142 | * @param cookie The cookie specified when this filter was attached. |
143 | * @param interface The interface the packet is being transmitted on. |
144 | * @param ioctl_cmd The ioctl command. |
145 | * @param ioctl_arg A pointer to the ioctl argument. |
146 | * @result Return: |
147 | * 0 - This filter function handled the ioctl. |
148 | * EOPNOTSUPP - This filter function does not understand/did not |
149 | * handle this ioctl. |
150 | * EJUSTRETURN - This filter function handled the ioctl, |
151 | * processing should stop. |
152 | * Anything Else - Processing will stop, the error will be |
153 | * returned. |
154 | */ |
155 | typedef errno_t (*iff_ioctl_func)(void *cookie, ifnet_t interface, |
156 | protocol_family_t protocol, unsigned long ioctl_cmd, void *ioctl_arg); |
157 | |
158 | /*! |
159 | * @typedef iff_detached_func |
160 | * |
161 | * @discussion iff_detached_func is called to notify the filter that it |
162 | * has been detached from an interface. This is the last call to |
163 | * the filter that will be made. A filter may be detached if the |
164 | * interface is detached or the detach filter function is called. |
165 | * In the case that the interface is being detached, your filter's |
166 | * event function will be called with the interface detaching event |
167 | * before the your detached function will be called. |
168 | * @param cookie The cookie specified when this filter was attached. |
169 | * @param interface The interface this filter was detached from. |
170 | */ |
171 | typedef void (*iff_detached_func)(void *cookie, ifnet_t interface); |
172 | |
173 | /*! |
174 | * @struct iff_filter |
175 | * @discussion This structure is used to define an interface filter for |
176 | * use with the iflt_attach function. |
177 | * @field iff_cookie A kext defined cookie that will be passed to all |
178 | * filter functions. |
179 | * @field iff_name A filter name used for debugging purposes. |
180 | * @field iff_protocol The protocol of the packets this filter is |
181 | * interested in. If you specify zero, packets from all protocols |
182 | * will be passed to the filter. |
183 | * @field iff_input The filter function to handle inbound packets, may |
184 | * be NULL. |
185 | * @field iff_output The filter function to handle outbound packets, |
186 | * may be NULL. |
187 | * @field iff_event The filter function to handle interface events, may |
188 | * be null. |
189 | * @field iff_ioctl The filter function to handle interface ioctls, may |
190 | * be null. |
191 | * @field iff_detached The filter function used to notify the filter that |
192 | * it has been detached. |
193 | */ |
194 | |
195 | struct iff_filter { |
196 | void *iff_cookie; |
197 | const char *iff_name; |
198 | protocol_family_t iff_protocol; |
199 | iff_input_func iff_input; |
200 | iff_output_func iff_output; |
201 | iff_event_func iff_event; |
202 | iff_ioctl_func iff_ioctl; |
203 | iff_detached_func iff_detached; |
204 | }; |
205 | |
206 | /*! |
207 | * @function iflt_attach |
208 | * @discussion Attaches an interface filter to an interface. |
209 | * @param interface The interface the filter should be attached to. |
210 | * @param filter A structure defining the filter. |
211 | * @param filter_ref A reference to the filter used to detach. |
212 | * @result 0 on success otherwise the errno error. |
213 | */ |
214 | #ifdef KERNEL_PRIVATE |
215 | extern errno_t iflt_attach_internal(ifnet_t interface, const struct iff_filter *filter, |
216 | interface_filter_t *filter_ref); |
217 | |
218 | #define iflt_attach(interface, filter, filter_ref) \ |
219 | iflt_attach_internal((interface), (filter), (filter_ref)) |
220 | #else |
221 | extern errno_t iflt_attach(ifnet_t interface, const struct iff_filter *filter, |
222 | interface_filter_t *filter_ref) |
223 | __NKE_API_DEPRECATED; |
224 | #endif /* KERNEL_PRIVATE */ |
225 | |
226 | /*! |
227 | * @function iflt_detach |
228 | * @discussion Detaches an interface filter from an interface. |
229 | * @param filter_ref The reference to the filter from iflt_attach. |
230 | */ |
231 | extern void iflt_detach(interface_filter_t filter_ref) |
232 | __NKE_API_DEPRECATED; |
233 | |
234 | __END_DECLS |
235 | #undef __NKE_API_DEPRECATED |
236 | #endif /* __KPI_INTERFACEFILTER__ */ |
237 | |