libsecurity_utilities/lib/fdmover.h

   1 /*
   2  * Copyright (c) 2000-2001,2003-2004 Apple Computer, Inc. All Rights Reserved.
   3  *
   4  * @APPLE_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. Please obtain a copy of the License at
  10  * http://www.opensource.apple.com/apsl/ and read it before using this
  11  * file.
  12  *
  13  * The Original Code and all software distributed under the License are
  14  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  15  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  16  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  18  * Please see the License for the specific language governing rights and
  19  * limitations under the License.
  20  *
  21  * @APPLE_LICENSE_HEADER_END@
  22  */
  23
  24
  25 //
  26 // fdmover - send/receive file descriptors over a UNIX domain socket connection
  27 //
  28 // An FdMover object is a very specialized Socket:
  29 // It must be bound to a UNIX domain address
  30 //
  31 #ifndef _H_FDMOVER
  32 #define _H_FDMOVER
  33
  34 #include "ip++.h"
  35 #include <vector>
  36
  37 using namespace UnixPlusPlus;
  38
  39
  40 namespace Security {
  41 namespace IPPlusPlus {
  42
  43
  44 // an ordered list of file descriptors
  45 typedef std::vector<FileDesc> FdVector;
  46
  47
  48 //
  49 // An FdMover - a specialized Socket for transferring file descriptors
  50 // across UNIX domain sockets.
  51 //
  52 class FdMover : public Socket {
  53 private:
  54         class Element : public cmsghdr {
  55         public:
  56                 void *operator new (size_t base, size_t more);
  57                 void operator delete (void *addr, size_t size);
  58
  59                 Element() { }
  60                 Element(int level, int type);
  61
  62                 template <class T> T &payload() { return *reinterpret_cast<T *>(CMSG_DATA(this)); }
  63                 size_t payloadSize() const              { return cmsg_len - ((caddr_t)CMSG_DATA(this) - (caddr_t)this); }
  64         };
  65
  66         class Message : public msghdr {
  67         public:
  68                 Message(const void *data, size_t length);
  69                 void set(Element *elem);
  70                 Element *element() const                        { return (Element *)msg_control; }
  71                 Element *next(Element *elem) const      { return (Element *)CMSG_NXTHDR(this, elem); }
  72
  73         public:
  74                 IOVec iovec;
  75         };
  76
  77 public:
  78         FdMover() { }
  79         FdMover(Socket s) : Socket(s) { }
  80
  81         size_t send(const void *data, size_t length, const FdVector &fds);
  82         size_t receive(void *data, size_t length, FdVector &fds);
  83
  84 private:
  85
  86 };
  87
  88
  89 }       // end namespace IPPlusPlus
  90 }       // end namespace Security
  91
  92
  93 #endif //_H_FDMOVER