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 (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21 /*
  22  * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
  23  * Use is subject to license terms.
  24  * Copyright (c) 2016, Chris Fraire <cfraire@me.com>.
  25  */
  26 
  27 #ifndef _PACKET_H
  28 #define _PACKET_H
  29 
  30 #pragma ident   "%Z%%M% %I%     %E% SMI"
  31 
  32 #include <sys/types.h>
  33 #include <netinet/in.h>
  34 #include <netinet/dhcp.h>
  35 #include <netinet/dhcp6.h>
  36 #include <dhcp_impl.h>
  37 
  38 #include "common.h"
  39 
  40 /*
  41  * packet.[ch] contain routines for manipulating, setting, and
  42  * transmitting DHCP/BOOTP packets.  see packet.c for descriptions on
  43  * how to use the exported functions.
  44  */
  45 
  46 #ifdef  __cplusplus
  47 extern "C" {
  48 #endif
  49 
  50 /*
  51  * data type for recv_pkt().  needed because we may want to wait for
  52  * several kinds of packets at once, and the existing enumeration of
  53  * DHCP packet types does not provide a way to do that easily.  here,
  54  * we light a different bit in the enumeration for each type of packet
  55  * we want to receive.
  56  *
  57  * Note that for DHCPv6, types 4 (CONFIRM), 5 (RENEW), 6 (REBIND), 12
  58  * (RELAY-FORW, and 13 (RELAY-REPL) are not in the table.  They're never
  59  * received by a client, so there's no reason to process them.  (SOLICIT,
  60  * REQUEST, DECLINE, RELEASE, and INFORMATION-REQUEST are also never seen by
  61  * clients, but are included for consistency.)
  62  *
  63  * Note also that the symbols are named for the DHCPv4 message types, and that
  64  * DHCPv6 has analogous message types.
  65  */
  66 
  67 typedef enum {
  68 
  69         DHCP_PUNTYPED   = 0x001,        /* untyped (BOOTP) message */
  70         DHCP_PDISCOVER  = 0x002,        /* in v6: SOLICIT (1) */
  71         DHCP_POFFER     = 0x004,        /* in v6: ADVERTISE (2) */
  72         DHCP_PREQUEST   = 0x008,        /* in v6: REQUEST (3) */
  73         DHCP_PDECLINE   = 0x010,        /* in v6: DECLINE (9) */
  74         DHCP_PACK       = 0x020,        /* in v6: REPLY (7), status == 0 */
  75         DHCP_PNAK       = 0x040,        /* in v6: REPLY (7), status != 0 */
  76         DHCP_PRELEASE   = 0x080,        /* in v6: RELEASE (8) */
  77         DHCP_PINFORM    = 0x100,        /* in v6: INFORMATION-REQUEST (11) */
  78         DHCP_PRECONFIG  = 0x200         /* v6 only: RECONFIGURE (10) */
  79 
  80 } dhcp_message_type_t;
  81 
  82 /*
  83  * A dhcp_pkt_t is used by the output-side packet manipulation functions.
  84  * While the structure is not strictly necessary, it allows a better separation
  85  * of functionality since metadata about the packet (such as its current
  86  * length) is stored along with the packet.
  87  *
  88  * Note that 'pkt' points to a dhcpv6_message_t if the packet is IPv6.
  89  */
  90 
  91 typedef struct dhcp_pkt_s {
  92         PKT             *pkt;           /* the real underlying packet */
  93         unsigned int    pkt_max_len;    /* its maximum length */
  94         unsigned int    pkt_cur_len;    /* its current length */
  95         boolean_t       pkt_isv6;
  96 } dhcp_pkt_t;
  97 
  98 /*
  99  * a `stop_func_t' is used by parts of dhcpagent that use the
 100  * retransmission capability of send_pkt().  this makes it so the
 101  * callers of send_pkt() decide when to stop retransmitting, which
 102  * makes more sense than hardcoding their instance-specific cases into
 103  * packet.c
 104  */
 105 
 106 typedef boolean_t stop_func_t(dhcp_smach_t *, unsigned int);
 107 
 108 /*
 109  * Default I/O and interface control sockets.
 110  */
 111 extern int v6_sock_fd;
 112 extern int v4_sock_fd;
 113 
 114 extern const in6_addr_t ipv6_all_dhcp_relay_and_servers;
 115 extern const in6_addr_t my_in6addr_any;
 116 
 117 PKT_LIST        *alloc_pkt_entry(size_t, boolean_t);
 118 void            free_pkt_entry(PKT_LIST *);
 119 void            free_pkt_list(PKT_LIST **);
 120 uchar_t         pkt_recv_type(const PKT_LIST *);
 121 uint_t          pkt_get_xid(const PKT *, boolean_t);
 122 dhcp_pkt_t      *init_pkt(dhcp_smach_t *, uchar_t);
 123 boolean_t       remove_pkt_opt(dhcp_pkt_t *, uint_t);
 124 boolean_t       update_v6opt_len(dhcpv6_option_t *, int);
 125 void            *add_pkt_opt(dhcp_pkt_t *, uint_t, const void *, uint_t);
 126 size_t          encode_dhcp_opt(void *, boolean_t, uint_t, const void *,
 127                         uint_t);
 128 void            *add_pkt_subopt(dhcp_pkt_t *, dhcpv6_option_t *, uint_t,
 129                     const void *, uint_t);
 130 void            *add_pkt_opt16(dhcp_pkt_t *, uint_t, uint16_t);
 131 void            *add_pkt_opt32(dhcp_pkt_t *, uint_t, uint32_t);
 132 void            *add_pkt_prl(dhcp_pkt_t *, dhcp_smach_t *);
 133 boolean_t       add_pkt_lif(dhcp_pkt_t *, dhcp_lif_t *, int, const char *);
 134 void            stop_pkt_retransmission(dhcp_smach_t *);
 135 void            retransmit_now(dhcp_smach_t *);
 136 PKT_LIST        *recv_pkt(int, int, boolean_t);
 137 boolean_t       pkt_v4_match(uchar_t, dhcp_message_type_t);
 138 void            pkt_smach_enqueue(dhcp_smach_t *, PKT_LIST *);
 139 boolean_t       send_pkt(dhcp_smach_t *, dhcp_pkt_t *, in_addr_t,
 140                     stop_func_t *);
 141 boolean_t       send_pkt_v6(dhcp_smach_t *, dhcp_pkt_t *, in6_addr_t,
 142                     stop_func_t *, uint_t, uint_t);
 143 boolean_t       dhcp_ip_default(void);
 144 
 145 #ifdef  __cplusplus
 146 }
 147 #endif
 148 
 149 #endif  /* _PACKET_H */