1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License, Version 1.0 only 6 * (the "License"). You may not use this file except in compliance 7 * with the License. 8 * 9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 10 * or http://www.opensolaris.org/os/licensing. 11 * See the License for the specific language governing permissions 12 * and limitations under the License. 13 * 14 * When distributing Covered Code, include this CDDL HEADER in each 15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 16 * If applicable, add the following below this CDDL HEADER, with the 17 * fields enclosed by brackets "[]" replaced with your own identifying 18 * information: Portions Copyright [yyyy] [name of copyright owner] 19 * 20 * CDDL HEADER END 21 */ 22 /* 23 * Copyright (c) 2000 by Sun Microsystems, Inc. 24 * All rights reserved. 25 */ 26 27 #ifndef _DHCP_NETWORK_H 28 #define _DHCP_NETWORK_H 29 30 #pragma ident "%Z%%M% %I% %E% SMI" 31 32 /* 33 * Implementation-specific data structures and constants for the binary 34 * files dhcp_network container. These structures are subject to change at 35 * any time. 36 */ 37 38 #include <sys/types.h> 39 #include <dhcp_svc_public.h> 40 41 #ifdef __cplusplus 42 extern "C" { 43 #endif 44 45 /* 46 * The client id hash size is based on the idea that, given a perfect hash, 47 * the hash chain length shouldn't be more than the number of buckets. 48 * Given a worst case network with 2^24 addresses, that means we should 49 * have 4096 buckets; we shrink this by a bit to make the dn_header_t size 50 * be a power of two (32768 bytes). Note that we assert that a header is 51 * this size in open_dn(). 52 */ 53 #define DN_CIDHASHSZ 4056 54 #define DN_MAGIC 0x0d6c92e4 /* "dhcpnet" in hexadecimal world */ 55 #define DN_NOIMAGE 0x80 /* image field not in use */ 56 #define DN_NOREC 0x00000000 /* "no record" id value, must be zero */ 57 #define DN_TEMPREC 0xffffffff /* "temp record" id value */ 58 #define DN_HASHHEAD 0xfffffffe /* "hash chain head" id value */ 59 60 typedef uint32_t dn_recid_t; /* record id type */ 61 62 /* 63 * Macros to compute the record id for a record with address `addr' in a 64 * container with netmask `mask', and to convert a record id `recid' to its 65 * starting file offset within its container. Note that we reserve the 66 * record id value of 0 for DN_NOREC for reasons explained in open_dn(). 67 */ 68 #define RECID(addr, mask) ((dn_recid_t)(((addr) & ~(mask)) + 1)) 69 #define RECID2OFFSET(recid) \ 70 (((recid) == DN_TEMPREC) ? offsetof(dn_header_t, dnh_temp) : \ 71 (sizeof (dn_header_t) + ((off_t)sizeof (dn_filerec_t) * ((recid) - 1)))) 72 73 /* 74 * What each dn_rec_t looks like on-disk -- contains the dn_rec_t, pointers 75 * to the previous and next dn_rec_t's on its client id hash. See the big 76 * theory statement in dhcp_network.c for a discussion on the redundant 77 * dn_recid_t's. 78 */ 79 typedef struct dn_filerec { 80 dn_recid_t rec_next[2]; /* id of next record in cidhash */ 81 dn_recid_t rec_prev[2]; /* id of prev record in cidhash */ 82 dn_rec_t rec_dn; /* actual dn_rec_t */ 83 } dn_filerec_t; 84 85 /* 86 * Header atop each dhcp_network container -- contains some basic 87 * information about the container and an array of buckets to chain client 88 * id hashes from. See the big theory statement in dhcp_network.c for a 89 * discussion on the redundant dn_recid_t's and the concept of "images". 90 */ 91 typedef struct dn_header { 92 unsigned char dnh_version; /* container version */ 93 unsigned char dnh_dirty; /* container might be dirty */ 94 unsigned char dnh_image; /* container's active image */ 95 unsigned char dnh_tempimage; /* temporary record's image */ 96 uint32_t dnh_magic; /* container magic */ 97 ipaddr_t dnh_network; /* network number of table */ 98 ipaddr_t dnh_netmask; /* netmask of network number */ 99 dn_filerec_t dnh_temp; /* temporary record used in modify_dn */ 100 uint32_t dnh_checks; /* number of check_dn full runs */ 101 uint32_t dnh_errors; /* number of errors caught */ 102 uint32_t dnh_pad[4]; /* for future use */ 103 104 /* 105 * Note: read_header() assumes that dnh_cidhash is the last member. 106 */ 107 dn_recid_t dnh_cidhash[DN_CIDHASHSZ][2]; /* cid hash buckets */ 108 } dn_header_t; 109 110 /* 111 * Per-instance state for each handle returned from open_dn. 112 */ 113 typedef struct dn_handle { 114 int dh_fd; /* fd for open file pointer */ 115 unsigned int dh_oflags; /* flags passed into open_dn */ 116 ipaddr_t dh_netmask; /* cached netmask of container */ 117 } dn_handle_t; 118 119 #ifdef __cplusplus 120 } 121 #endif 122 123 #endif /* _DHCP_NETWORK_H */ 124