/ duct-tape / xnu / bsd / sys / kern_event.h
kern_event.h
  1  /*
  2   * Copyright (c) 2000-2014 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  /* Copyright (c) 1998, 1999 Apple Computer, Inc. All Rights Reserved */
 29  /*!
 30   *       @header kern_event.h
 31   *       This header defines in-kernel functions for generating kernel events as
 32   *       well as functions for receiving kernel events using a kernel event
 33   *       socket.
 34   */
 35  
 36  #ifndef SYS_KERN_EVENT_H
 37  #define SYS_KERN_EVENT_H
 38  
 39  #include <sys/appleapiopts.h>
 40  #include <sys/ioccom.h>
 41  #include <sys/sys_domain.h>
 42  
 43  #define KEV_SNDSPACE    (4 * 1024)
 44  #define KEV_RECVSPACE   (32 * 1024)
 45  
 46  #define KEV_ANY_VENDOR          0
 47  #define KEV_ANY_CLASS           0
 48  #define KEV_ANY_SUBCLASS        0
 49  
 50  /*
 51   * Vendor Code
 52   */
 53  
 54  /*!
 55   *       @defined KEV_VENDOR_APPLE
 56   *       @discussion Apple generated kernel events use the hard coded vendor code
 57   *       value of 1. Third party kernel events use a dynamically allocated vendor
 58   *       code. The vendor code can be found using the SIOCGKEVVENDOR ioctl.
 59   */
 60  #define KEV_VENDOR_APPLE        1
 61  
 62  /*
 63   * Definition of top-level classifications for KEV_VENDOR_APPLE
 64   */
 65  
 66  /*!
 67   *       @defined KEV_NETWORK_CLASS
 68   *       @discussion Network kernel event class.
 69   */
 70  #define KEV_NETWORK_CLASS       1
 71  
 72  /*!
 73   *       @defined KEV_IOKIT_CLASS
 74   *       @discussion IOKit kernel event class.
 75   */
 76  #define KEV_IOKIT_CLASS         2
 77  
 78  /*!
 79   *       @defined KEV_SYSTEM_CLASS
 80   *       @discussion System kernel event class.
 81   */
 82  #define KEV_SYSTEM_CLASS        3
 83  
 84  /*!
 85   *       @defined KEV_APPLESHARE_CLASS
 86   *       @discussion AppleShare kernel event class.
 87   */
 88  #define KEV_APPLESHARE_CLASS    4
 89  
 90  /*!
 91   *       @defined KEV_FIREWALL_CLASS
 92   *       @discussion Firewall kernel event class.
 93   */
 94  #define KEV_FIREWALL_CLASS      5
 95  
 96  /*!
 97   *       @defined KEV_IEEE80211_CLASS
 98   *       @discussion IEEE 802.11 kernel event class.
 99   */
100  #define KEV_IEEE80211_CLASS     6
101  
102  /*
103   * The following struct is KPI, but it was originally defined with a trailing
104   * array member of size one, intended to be used as a Variable-Length Array.
105   * That's problematic because the compiler doesn't know that the array is
106   * accessed out-of-bounds and can assume it isn't. This makes
107   * -Warray-bounds-pointer-arithmetic sad. We can't just change the code because
108   * it requires users to also change their uses of the class, at a minimum
109   * because kern_event_msg's size changes when making the last member a VLA. This
110   * macro allows users of this KPI to opt-in to the new behavior.
111   */
112  #if defined(XNU_KERN_EVENT_DATA_IS_VLA)
113  #define XNU_KERN_EVENT_DATA_SIZE /* nothing, it's a VLA */
114  #else
115  #define XNU_KERN_EVENT_DATA_SIZE 1
116  #endif
117  
118  /*!
119   *       @struct kern_event_msg
120   *       @discussion This structure is prepended to all kernel events. This
121   *               structure is used to determine the format of the remainder of
122   *               the kernel event. This structure will appear on all messages
123   *               received on a kernel event socket. To post a kernel event, a
124   *               slightly different structure is used.
125   *       @field total_size Total size of the kernel event message including the
126   *               header.
127   *       @field vendor_code The vendor code indicates which vendor generated the
128   *               kernel event. This gives every vendor a unique set of classes
129   *               and subclasses to use. Use the SIOCGKEVVENDOR ioctl to look up
130   *               vendor codes for vendors other than Apple. Apple uses
131   *               KEV_VENDOR_APPLE.
132   *       @field kev_class The class of the kernel event.
133   *       @field kev_subclass The subclass of the kernel event.
134   *       @field id Monotonically increasing value.
135   *       @field event_code The event code.
136   *       @field event_data Any additional data about this event. Format will
137   *               depend on the vendor_code, kev_class, kev_subclass, and
138   *               event_code. The length of the event_data can be determined
139   *               using total_size - KEV_MSG_HEADER_SIZE.
140   */
141  struct kern_event_msg {
142  	u_int32_t       total_size;     /* Size of entire event msg */
143  	u_int32_t       vendor_code;    /* For non-Apple extensibility */
144  	u_int32_t       kev_class;      /* Layer of event source */
145  	u_int32_t       kev_subclass;   /* Component within layer */
146  	u_int32_t       id;             /* Monotonically increasing value */
147  	u_int32_t       event_code;     /* unique code */
148  	u_int32_t       event_data[XNU_KERN_EVENT_DATA_SIZE];   /* One or more data words */
149  };
150  
151  /*!
152   *       @defined KEV_MSG_HEADER_SIZE
153   *       @discussion Size of the header portion of the kern_event_msg structure.
154   *               This accounts for everything right up to event_data. The size
155   *               of the data can be found by subtracting KEV_MSG_HEADER_SIZE
156   *               from the total size from the kern_event_msg.
157   */
158  #define KEV_MSG_HEADER_SIZE (offsetof(struct kern_event_msg, event_data[0]))
159  
160  /*!
161   *       @struct kev_request
162   *       @discussion This structure is used with the SIOCSKEVFILT and
163   *               SIOCGKEVFILT to set and get the control filter setting for a
164   *               kernel control socket.
165   *       @field total_size Total size of the kernel event message including the
166   *               header.
167   *       @field vendor_code All kernel events that don't match this vendor code
168   *               will be ignored. KEV_ANY_VENDOR can be used to receive kernel
169   *               events with any vendor code.
170   *       @field kev_class All kernel events that don't match this class will be
171   *               ignored. KEV_ANY_CLASS can be used to receive kernel events with
172   *               any class.
173   *       @field kev_subclass All kernel events that don't match this subclass
174   *               will be ignored. KEV_ANY_SUBCLASS can be used to receive kernel
175   *               events with any subclass.
176   */
177  struct kev_request {
178  	u_int32_t       vendor_code;
179  	u_int32_t       kev_class;
180  	u_int32_t       kev_subclass;
181  };
182  
183  /*!
184   *       @defined KEV_VENDOR_CODE_MAX_STR_LEN
185   *       @discussion This define sets the maximum length of a string that can be
186   *               used to identify a vendor or kext when looking up a vendor code.
187   */
188  #define KEV_VENDOR_CODE_MAX_STR_LEN     200
189  
190  /*!
191   *       @struct kev_vendor_code
192   *       @discussion This structure is used with the SIOCGKEVVENDOR ioctl to
193   *               convert from a string identifying a kext or vendor, in the
194   *               form of a bundle identifier, to a vendor code.
195   *       @field vendor_code After making the SIOCGKEVVENDOR ioctl call, this will
196   *               be filled in with the vendor code if there is one.
197   *       @field vendor_string A bundle style identifier.
198   */
199  #pragma pack(4)
200  struct kev_vendor_code {
201  	u_int32_t       vendor_code;
202  	char            vendor_string[KEV_VENDOR_CODE_MAX_STR_LEN];
203  };
204  #pragma pack()
205  
206  /*!
207   *       @defined SIOCGKEVID
208   *       @discussion Retrieve the current event id. Each event generated will
209   *               have a new id. The next event to be generated will have an id
210   *               of id+1.
211   */
212  #define SIOCGKEVID      _IOR('e', 1, u_int32_t)
213  
214  /*!
215   *       @defined SIOCSKEVFILT
216   *       @discussion Set the kernel event filter for this socket. Kernel events
217   *               not matching this filter will not be received on this socket.
218   */
219  #define SIOCSKEVFILT    _IOW('e', 2, struct kev_request)
220  
221  /*!
222   *       @defined SIOCGKEVFILT
223   *       @discussion Retrieve the kernel event filter for this socket. Kernel
224   *               events not matching this filter will not be received on this
225   *               socket.
226   */
227  #define SIOCGKEVFILT    _IOR('e', 3, struct kev_request)
228  
229  /*!
230   *       @defined SIOCGKEVVENDOR
231   *       @discussion Lookup the vendor code for the specified vendor. ENOENT will
232   *               be returned if a vendor code for that vendor string does not
233   *               exist.
234   */
235  #define SIOCGKEVVENDOR  _IOWR('e', 4, struct kev_vendor_code)
236  
237  #ifdef PRIVATE
238  struct xkevtpcb {
239  	u_int32_t       kep_len;
240  	u_int32_t       kep_kind;
241  	u_int64_t       kep_evtpcb;
242  	u_int32_t       kep_vendor_code_filter;
243  	u_int32_t       kep_class_filter;
244  	u_int32_t       kep_subclass_filter;
245  };
246  
247  struct kevtstat {
248  	u_int64_t       kes_pcbcount __attribute__((aligned(8)));
249  	u_int64_t       kes_gencnt __attribute__((aligned(8)));
250  	u_int64_t       kes_badvendor __attribute__((aligned(8)));
251  	u_int64_t       kes_toobig __attribute__((aligned(8)));
252  	u_int64_t       kes_nomem __attribute__((aligned(8)));
253  	u_int64_t       kes_fullsock __attribute__((aligned(8)));
254  	u_int64_t       kes_posted __attribute__((aligned(8)));
255  };
256  #endif /* PRIVATE */
257  
258  #ifdef KERNEL
259  /*!
260   *       @define N_KEV_VECTORS
261   *       @discussion The maximum number of kev_d_vectors for a kernel event.
262   */
263  #define N_KEV_VECTORS   5
264  
265  /*!
266   *       @struct kev_d_vectors
267   *       @discussion This structure is used to append some data to a kernel
268   *               event.
269   *       @field data_length The length of data.
270   *       @field data_ptr A pointer to data.
271   */
272  struct kev_d_vectors {
273  	u_int32_t       data_length;    /* Length of the event data */
274  	void            *data_ptr;      /* Pointer to event data */
275  };
276  
277  /*!
278   *       @struct kev_msg
279   *       @discussion This structure is used when posting a kernel event.
280   *       @field vendor_code The vendor code assigned by kev_vendor_code_find.
281   *       @field kev_class The event's class.
282   *       @field kev_class The event's subclass.
283   *       @field kev_class The event's code.
284   *       @field dv An array of vectors describing additional data to be appended
285   *               to the kernel event.
286   */
287  struct kev_msg {
288  	u_int32_t vendor_code;          /* For non-Apple extensibility */
289  	u_int32_t kev_class;            /* Layer of event source */
290  	u_int32_t kev_subclass;         /* Component within layer */
291  	u_int32_t event_code;           /* The event code */
292  	struct kev_d_vectors dv[N_KEV_VECTORS]; /* Up to n data vectors */
293  };
294  
295  /*!
296   *       @function kev_vendor_code_find
297   *       @discussion Lookup a vendor_code given a unique string. If the vendor
298   *               code has not been used since launch, a unique integer will be
299   *               assigned for that string. Vendor codes will remain the same
300   *               until the machine is rebooted.
301   *       @param vendor_string A bundle style vendor identifier(i.e. com.apple).
302   *       @param vendor_code Upon return, a unique vendor code for use when
303   *               posting kernel events.
304   *       @result May return ENOMEM if memory constraints prevent allocation of a
305   *               new vendor code.
306   */
307  errno_t kev_vendor_code_find(const char *vendor_string, u_int32_t *vendor_code);
308  
309  /*!
310   *       @function kev_msg_post
311   *       @discussion Post a kernel event message.
312   *       @param event_msg A structure defining the kernel event message to post.
313   *       @result Will return zero upon success. May return a number of errors
314   *               depending on the type of failure. EINVAL indicates that there
315   *               was something wrong with the kerne event. The vendor code of
316   *               the kernel event must be assigned using kev_vendor_code_find.
317   *               If the message is too large, EMSGSIZE will be returned.
318   */
319  errno_t kev_msg_post(struct kev_msg *event_msg);
320  
321  #ifdef PRIVATE
322  /*
323   * Internal version of kev_msg_post. Allows posting Apple vendor code kernel
324   * events.
325   */
326  int     kev_post_msg(struct kev_msg *event);
327  
328  LIST_HEAD(kern_event_head, kern_event_pcb);
329  
330  struct kern_event_pcb {
331  	decl_lck_mtx_data(, evp_mtx);   /* per-socket mutex */
332  	LIST_ENTRY(kern_event_pcb) evp_link;    /* glue on list of all PCBs */
333  	struct socket *evp_socket;              /* pointer back to socket */
334  	u_int32_t evp_vendor_code_filter;
335  	u_int32_t evp_class_filter;
336  	u_int32_t evp_subclass_filter;
337  };
338  
339  #define sotoevpcb(so)   ((struct kern_event_pcb *)((so)->so_pcb))
340  
341  #endif /* PRIVATE */
342  #endif /* KERNEL */
343  #endif /* SYS_KERN_EVENT_H */