dhcp.h

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/*  $OpenBSD: dhcp.h,v 1.5 2004/05/04 15:49:49 deraadt Exp $    */

/* Protocol structures... */

/*
 * Copyright (c) 1995, 1996 The Internet Software Consortium.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of The Internet Software Consortium nor the names
 *    of its contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE INTERNET SOFTWARE CONSORTIUM AND
 * CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE INTERNET SOFTWARE CONSORTIUM OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * This software has been written for the Internet Software Consortium
 * by Ted Lemon <mellon@fugue.com> in cooperation with Vixie
 * Enterprises.  To learn more about the Internet Software Consortium,
 * see ``http://www.vix.com/isc''.  To learn more about Vixie
 * Enterprises, see ``http://www.vix.com''.
 */

#define DHCP_UDP_OVERHEAD   (14 + /* Ethernet header */ \
                 20 + /* IP header */       \
                 8)   /* UDP header */
#define DHCP_SNAME_LEN      64
#define DHCP_FILE_LEN       128
#define DHCP_FIXED_NON_UDP  236
#define DHCP_FIXED_LEN      (DHCP_FIXED_NON_UDP + DHCP_UDP_OVERHEAD)
                        /* Everything but options. */
#define DHCP_MTU_MAX        1500
#define DHCP_OPTION_LEN     (DHCP_MTU_MAX - DHCP_FIXED_LEN)

#define BOOTP_MIN_LEN       300
#define DHCP_MIN_LEN        548

struct dhcp_packet {
    u_int8_t  op;       /* Message opcode/type */
    u_int8_t  htype;    /* Hardware addr type (see net/if_types.h) */
    u_int8_t  hlen;     /* Hardware addr length */
    u_int8_t  hops;     /* Number of relay agent hops from client */
    u_int32_t xid;      /* Transaction ID */
    u_int16_t secs;     /* Seconds since client started looking */
    u_int16_t flags;    /* Flag bits */
    struct in_addr ciaddr;  /* Client IP address (if already in use) */
    struct in_addr yiaddr;  /* Client IP address */
    struct in_addr siaddr;  /* IP address of next server to talk to */
    struct in_addr giaddr;  /* DHCP relay agent IP address */
    unsigned char chaddr[16];   /* Client hardware address */
    char sname[DHCP_SNAME_LEN]; /* Server name */
    char file[DHCP_FILE_LEN];   /* Boot filename */
    unsigned char options[DHCP_OPTION_LEN];
                /* Optional parameters
                   (actual length dependent on MTU). */
};

/* BOOTP (rfc951) message types */
#define BOOTREQUEST 1
#define BOOTREPLY   2

/* Possible values for flags field... */
#define BOOTP_BROADCAST 32768L

/* Possible values for hardware type (htype) field... */
#define HTYPE_ETHER 1       /* Ethernet         */
#define HTYPE_IEEE802   6       /* IEEE 802.2 Token Ring... */
#define HTYPE_FDDI  8       /* FDDI...          */

/* Magic cookie validating dhcp options field (and bootp vendor
   extensions field). */
#define DHCP_OPTIONS_COOKIE "\143\202\123\143"


/* DHCP Option codes: */

#define DHO_PAD             0
#define DHO_SUBNET_MASK         1
#define DHO_TIME_OFFSET         2
#define DHO_ROUTERS         3
#define DHO_TIME_SERVERS        4
#define DHO_NAME_SERVERS        5
#define DHO_DOMAIN_NAME_SERVERS     6
#define DHO_LOG_SERVERS         7
#define DHO_COOKIE_SERVERS      8
#define DHO_LPR_SERVERS         9
#define DHO_IMPRESS_SERVERS     10
#define DHO_RESOURCE_LOCATION_SERVERS   11
#define DHO_HOST_NAME           12
#define DHO_BOOT_SIZE           13
#define DHO_MERIT_DUMP          14
#define DHO_DOMAIN_NAME         15
#define DHO_SWAP_SERVER         16
#define DHO_ROOT_PATH           17
#define DHO_EXTENSIONS_PATH     18
#define DHO_IP_FORWARDING       19
#define DHO_NON_LOCAL_SOURCE_ROUTING    20
#define DHO_POLICY_FILTER       21
#define DHO_MAX_DGRAM_REASSEMBLY    22
#define DHO_DEFAULT_IP_TTL      23
#define DHO_PATH_MTU_AGING_TIMEOUT  24
#define DHO_PATH_MTU_PLATEAU_TABLE  25
#define DHO_INTERFACE_MTU       26
#define DHO_ALL_SUBNETS_LOCAL       27
#define DHO_BROADCAST_ADDRESS       28
#define DHO_PERFORM_MASK_DISCOVERY  29
#define DHO_MASK_SUPPLIER       30
#define DHO_ROUTER_DISCOVERY        31
#define DHO_ROUTER_SOLICITATION_ADDRESS 32
#define DHO_STATIC_ROUTES       33
#define DHO_TRAILER_ENCAPSULATION   34
#define DHO_ARP_CACHE_TIMEOUT       35
#define DHO_IEEE802_3_ENCAPSULATION 36
#define DHO_DEFAULT_TCP_TTL     37
#define DHO_TCP_KEEPALIVE_INTERVAL  38
#define DHO_TCP_KEEPALIVE_GARBAGE   39
#define DHO_NIS_DOMAIN          40
#define DHO_NIS_SERVERS         41
#define DHO_NTP_SERVERS         42
#define DHO_VENDOR_ENCAPSULATED_OPTIONS 43
#define DHO_NETBIOS_NAME_SERVERS    44
#define DHO_NETBIOS_DD_SERVER       45
#define DHO_NETBIOS_NODE_TYPE       46
#define DHO_NETBIOS_SCOPE       47
#define DHO_FONT_SERVERS        48
#define DHO_X_DISPLAY_MANAGER       49
#define DHO_DHCP_REQUESTED_ADDRESS  50
#define DHO_DHCP_LEASE_TIME     51
#define DHO_DHCP_OPTION_OVERLOAD    52
#define DHO_DHCP_MESSAGE_TYPE       53
#define DHO_DHCP_SERVER_IDENTIFIER  54
#define DHO_DHCP_PARAMETER_REQUEST_LIST 55
#define DHO_DHCP_MESSAGE        56
#define DHO_DHCP_MAX_MESSAGE_SIZE   57
#define DHO_DHCP_RENEWAL_TIME       58
#define DHO_DHCP_REBINDING_TIME     59
#define DHO_DHCP_CLASS_IDENTIFIER   60
#define DHO_DHCP_CLIENT_IDENTIFIER  61
#define DHO_DHCP_USER_CLASS_ID      77
#define DHO_END             255

/* DHCP message types. */
#define DHCPDISCOVER    1
#define DHCPOFFER   2
#define DHCPREQUEST 3
#define DHCPDECLINE 4
#define DHCPACK     5
#define DHCPNAK     6
#define DHCPRELEASE 7
#define DHCPINFORM  8