bsd/net/kpi_protocol.h

   1 /*
   2  * Copyright (c) 2008 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_protocol.h
  30         This header defines an API to interact with protocols in the kernel.
  31         The KPIs in this header file can be used to interact with protocols
  32         that already exist in the stack. These KPIs can be used to support
  33         existing protocols over media types that are not natively supported
  34         in the kernel, such as ATM.
  35  */
  36
  37 #ifndef __KPI_PROTOCOL__
  38 #define __KPI_PROTOCOL__
  39 #include <sys/kernel_types.h>
  40 #include <net/kpi_interface.h>
  41
  42
  43 __BEGIN_DECLS
  44
  45 /******************************************************************************/
  46 /* Protocol input/inject                                                      */
  47 /******************************************************************************/
  48
  49 #ifdef KERNEL_PRIVATE
  50 /*!
  51         @typedef protocol_input_handler
  52         @discussion protocol_input_handler is called to input a packet. If
  53                 your protocol has specified a global lock, the lock will be held
  54                 when this funciton is called.
  55         @pararm protocol The protocol this packet is intended for.
  56         @param packet The packet that should be input.
  57  */
  58 typedef void (*proto_input_handler)(protocol_family_t protocol, mbuf_t packet);
  59
  60 /*!
  61         @typedef proto_input_detached_handler
  62         @discussion proto_input_detached_handler is called to notify the
  63                 protocol that it has been detached. When this function is
  64                 called, the proto_input_handler will not be called again, making
  65                 it safe to unload.
  66         @pararm protocol The protocol detached.
  67  */
  68 typedef void (*proto_input_detached_handler)(protocol_family_t protocol);
  69
  70 /*!
  71         @function proto_register_input
  72         @discussion Allows the caller to specify the functions called when a
  73                 packet for a protocol is received.
  74         @param protocol The protocol family these functions will receive
  75                 packets for.
  76         @param input The function called when a packet is input.
  77         @param chains Input function supports packet chains.
  78         @result A errno error on failure.
  79  */
  80 extern errno_t proto_register_input(protocol_family_t protocol,
  81     proto_input_handler input, proto_input_detached_handler detached,
  82     int chains);
  83
  84 /*!
  85         @function proto_unregister_input
  86         @discussion Allows the caller to unregister the input and inject
  87                 functions for a protocol. The input/inject functions may not be
  88                 unregistered immediately if there is a chance they are in use.
  89                 To notify the owner when the functions are no longer in use, the
  90                 proto_detached_handler function will be called. It is not safe
  91                 to unload until the proto_detached_handler is called.
  92         @param protocol The protocol family these functions will receive
  93                 packets for.
  94         @param input The function called when a packet is input.
  95         @param inject The function to called when a packet is injected (not
  96                 on the normal input path).
  97         @result A errno error on failure.
  98  */
  99 extern void proto_unregister_input(protocol_family_t protocol);
 100 #endif /* KERNEL_PRIVATE */
 101
 102 /*!
 103         @function proto_input
 104         @discussion Inputs a packet on the specified protocol from the input
 105                 path.
 106         @param protocol The protocol of the packet.
 107         @param packet The first packet in a chain of packets to be input.
 108         @result A errno error on failure. Unless proto_input returns zero,
 109                 the caller is responsible for freeing the mbuf.
 110  */
 111 extern errno_t proto_input(protocol_family_t protocol, mbuf_t packet);
 112
 113 /*!
 114         @function proto_inject
 115         @discussion Injects a packet on the specified protocol from
 116                 anywhere. To avoid recursion, the protocol may need to queue the
 117                 packet to be handled later.
 118         @param protocol The protocol of the packet.
 119         @param packet The first packet in a chain of packets to be injected.
 120         @result A errno error on failure. Unless proto_inject returns zero,
 121                 the caller is responsible for freeing the mbuf.
 122  */
 123 extern errno_t proto_inject(protocol_family_t protocol, mbuf_t packet);
 124
 125
 126 /******************************************************************************/
 127 /* Protocol plumbing                                                          */
 128 /******************************************************************************/
 129
 130 /*!
 131         @typedef proto_plumb_handler
 132         @discussion proto_plumb_handler is called to attach a protocol to an
 133                 interface. A typical protocol plumb function would fill out an
 134                 ifnet_attach_proto_param and call ifnet_attach_protocol.
 135         @param ifp The interface the protocol should be attached to.
 136         @param protocol_family The protocol that should be attached to the
 137                 interface.
 138         @result
 139                 A non-zero value of the attach failed.
 140  */
 141 typedef errno_t (*proto_plumb_handler)(ifnet_t ifp, protocol_family_t protocol);
 142
 143 /*!
 144         @typedef proto_unplumb_handler
 145         @discussion proto_unplumb_handler is called to detach a protocol
 146                 from an interface. A typical unplumb function would call
 147                 ifnet_detach_protocol and perform any necessary cleanup.
 148         @param ifp The interface the protocol should be detached from.
 149         @param protocol_family The protocol that should be detached from the
 150                 interface.
 151  */
 152 typedef void (*proto_unplumb_handler)(ifnet_t ifp, protocol_family_t protocol);
 153
 154 /*!
 155         @function proto_register_plumber
 156         @discussion Allows the caller to specify the functions called when a
 157                 protocol is attached to an interface belonging to the specified
 158                 family and when that protocol is detached.
 159         @param proto_fam The protocol family these plumbing functions will
 160                 handle.
 161         @param if_fam The interface family these plumbing functions will
 162                 handle.
 163         @param plumb The function to call to attach the protocol to an
 164                 interface.
 165         @param unplumb The function to call to detach the protocol to an
 166                 interface, may be NULL in which case ifnet_detach_protocol will
 167                 be used to detach the protocol.
 168         @result A non-zero value of the attach failed.
 169  */
 170 extern errno_t proto_register_plumber(protocol_family_t proto_fam,
 171     ifnet_family_t if_fam, proto_plumb_handler plumb,
 172     proto_unplumb_handler unplumb);
 173
 174 /*!
 175         @function proto_unregister_plumber
 176         @discussion Unregisters a previously registered plumbing function.
 177         @param proto_fam The protocol family these plumbing functions
 178                 handle.
 179         @param if_fam The interface family these plumbing functions handle.
 180  */
 181 extern void proto_unregister_plumber(protocol_family_t proto_fam,
 182     ifnet_family_t if_fam);
 183
 184 #ifdef KERNEL_PRIVATE
 185 /*
 186         @function proto_plumb
 187         @discussion Plumbs a protocol to an actual interface.  This will find
 188                 a registered protocol module and call its attach function.
 189                 The module will typically call dlil_attach_protocol() with the
 190                 appropriate parameters.
 191         @param protocol_family The protocol family.
 192         @param ifp The interface to plumb the protocol to.
 193         @result 0: No error.
 194                 ENOENT: No module was registered.
 195                 Other: Error returned by the attach_proto function
 196 */
 197 extern errno_t proto_plumb(protocol_family_t protocol_family, ifnet_t ifp);
 198
 199 /*
 200         @function proto_unplumb
 201         @discussion Unplumbs a protocol from an interface.  This will find
 202                 a registered protocol module and call its detach function.
 203                 The module will typically call dlil_detach_protocol() with
 204                 the appropriate parameters.  If no module is found, this
 205                 function will call dlil_detach_protocol directly().
 206         @param protocol_family The protocol family.
 207         @param ifp The interface to unplumb the protocol from.
 208         @result 0: No error.
 209                 ENOENT: No module was registered.
 210                 Other: Error returned by the attach_proto function
 211 */
 212 extern errno_t proto_unplumb(protocol_family_t protocol_family, ifnet_t ifp);
 213
 214 __private_extern__ void
 215 proto_kpi_init(void) __attribute__((section("__TEXT, initcode")));
 216
 217 #endif /* KERNEL_PRIVATE */
 218 __END_DECLS
 219
 220 #endif /* __KPI_PROTOCOL__ */