| 1 | /* -*-c-*- |
| 2 | * |
| 3 | * $Id: unet.h,v 1.1 2001/01/25 22:03:39 mdw Exp $ |
| 4 | * |
| 5 | * User-space network device support. |
| 6 | * |
| 7 | * (c) 1998 Mark Wooding |
| 8 | */ |
| 9 | |
| 10 | /*----- Licensing notice --------------------------------------------------* |
| 11 | * |
| 12 | * This file is part of Usernet. |
| 13 | * |
| 14 | * Usernet is free software; you can redistribute it and/or modify |
| 15 | * it under the terms of the GNU General Public License as published by |
| 16 | * the Free Software Foundation; either version 2 of the License, or |
| 17 | * (at your option) any later version. |
| 18 | * |
| 19 | * Usernet is distributed in the hope that it will be useful, |
| 20 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 21 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 22 | * GNU General Public License for more details. |
| 23 | * |
| 24 | * You should have received a copy of the GNU General Public License |
| 25 | * along with Usernet; if not, write to the Free Software Foundation, |
| 26 | * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. |
| 27 | */ |
| 28 | |
| 29 | /*----- Revision history --------------------------------------------------* |
| 30 | * |
| 31 | * $Log: unet.h,v $ |
| 32 | * Revision 1.1 2001/01/25 22:03:39 mdw |
| 33 | * Initial check-in (somewhat belated). |
| 34 | * |
| 35 | */ |
| 36 | |
| 37 | #ifndef _LINUX_UNET_H |
| 38 | #define _LINUX_UNET_H |
| 39 | |
| 40 | #ifdef __cplusplus |
| 41 | extern "C" { |
| 42 | #endif |
| 43 | |
| 44 | /*----- What's the story? -------------------------------------------------* |
| 45 | * |
| 46 | * Based on a conversation with Clive Jones about FreeBSD's tunnel device, |
| 47 | * I've decided to try to write something similar. The basic idea is to |
| 48 | * tie together a character device and a network interface, so that anything |
| 49 | * written to one pops out the other. I create a device /dev/unet. |
| 50 | * Each open(2) of my device creates a network device, whose name can be |
| 51 | * read by calling ioctl(2). A read(2) on the device fetches the next |
| 52 | * packet received from the network interface; conversely, a write(2) sends |
| 53 | * a network packet through the interface. |
| 54 | * |
| 55 | * Permissions on /dev/unet ought to be fairly strict. Remember that |
| 56 | * anyone who can get access to it can inject arbitrary IP packets. |
| 57 | * |
| 58 | * This is my first stab at hacking Linux, so there'll be mistakes and |
| 59 | * infelicities. All I ask is that you tell me what they are. |
| 60 | * |
| 61 | * [mdw] |
| 62 | * mdw@excessus.demon.co.uk |
| 63 | */ |
| 64 | |
| 65 | /*----- @ioctl@(2) calls supported ----------------------------------------*/ |
| 66 | |
| 67 | /* --- @UNIOCGINFO@ --- * |
| 68 | * |
| 69 | * Reads useful information about a unet. The argument is a pointer to a |
| 70 | * @unet_info@ structure, which is filled in by the call. As a special case, |
| 71 | * the argument may be a null pointer, in which case the call does nothing |
| 72 | * and may be used to verify that a file descriptor refers to a Usernet |
| 73 | * attachment. |
| 74 | */ |
| 75 | |
| 76 | #define UNIOCGINFO _IOR('U', 0, sizeof(struct unet_info)) |
| 77 | |
| 78 | #define UNET_NAMEMAX 20 |
| 79 | |
| 80 | struct unet_info { |
| 81 | char uni_ifname[UNET_NAMEMAX]; /* Interface name string */ |
| 82 | unsigned short uni_mtu; /* Maximum transmission unit */ |
| 83 | unsigned short uni_family; /* My address family */ |
| 84 | unsigned short uni_proto; /* Protocol to stamp on packets */ |
| 85 | unsigned int uni_flags; /* Various useful flags */ |
| 86 | }; |
| 87 | |
| 88 | #define UNIF_TRANS 1 /* This device is transient */ |
| 89 | #define UNIF_OPEN 2 /* Not useful to users */ |
| 90 | #define UNIF_DEBUG 4 /* Debugging enable flag */ |
| 91 | |
| 92 | /* --- @UNIOCSDEBUG@ --- * |
| 93 | * |
| 94 | * Sets the debugging state for the attachment. When the debug flag is set, |
| 95 | * all packets sent and received by the device will be logged, as will other |
| 96 | * events. |
| 97 | */ |
| 98 | |
| 99 | #define UNIOCSDEBUG _IO('U', 1) |
| 100 | |
| 101 | /* --- @UNIOCGPROTO@ --- * |
| 102 | * |
| 103 | * Reads the protocol stamped on packets received through the character |
| 104 | * device interface. The default is @ETH_P_IP@; the various values are |
| 105 | * defined in @<linux/if_ether.h>@. |
| 106 | */ |
| 107 | |
| 108 | #define UNIOCGPROTO _IO('U', 2) |
| 109 | |
| 110 | /* --- @UNIOCSPROTO@ --- * |
| 111 | * |
| 112 | * Sets the protocol to be stamped on outgoing packets. |
| 113 | */ |
| 114 | |
| 115 | #define UNIOCSPROTO _IO('U', 3) |
| 116 | |
| 117 | /* --- @UNIOCGGDEBUG@ --- * |
| 118 | * |
| 119 | * Gets the global debugging flag. |
| 120 | */ |
| 121 | |
| 122 | #define UNIOCGGDEBUG _IO('U', 4) |
| 123 | |
| 124 | /* --- @UNIOCSGDEBUG@ --- * |
| 125 | * |
| 126 | * Sets the global debugging flag. This is only available when runtime |
| 127 | * debugging configuration is compiled in. |
| 128 | */ |
| 129 | |
| 130 | #define UNIOCSGDEBUG _IO('U', 5) |
| 131 | |
| 132 | /* --- @UNIOCDUMP@ --- * |
| 133 | * |
| 134 | * Dumps a unet block's information to the debug device. |
| 135 | */ |
| 136 | |
| 137 | #define UNIOCDUMP _IO('U', 6) |
| 138 | |
| 139 | /* --- @UNIOCGMAXIF@ --- * |
| 140 | * |
| 141 | * Returns the maximum number of interfaces allowed. |
| 142 | */ |
| 143 | |
| 144 | #define UNIOCGMAXIF _IO('U', 7) |
| 145 | |
| 146 | /* --- @UNIOCGMAXIF@ --- * |
| 147 | * |
| 148 | * Sets the maximum number of interfaces allowed. It's an error to lower |
| 149 | * this below the number of the highest currently-used interface. |
| 150 | */ |
| 151 | |
| 152 | #define UNIOCSMAXIF _IO('U', 8) |
| 153 | |
| 154 | /*----- That's all, folks -------------------------------------------------*/ |
| 155 | |
| 156 | #ifdef __cplusplus |
| 157 | } |
| 158 | #endif |
| 159 | |
| 160 | #endif |