usr/src/lib/libdhcpagent/common/dhcpagent_ipc.h

   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 2009 Sun Microsystems, Inc.  All rights reserved.
  23  * Use is subject to license terms.
  24  */
  25 /*
  26  * Copyright (c) 2013, 2015 by Delphix. All rights reserved.
  27  */
  28
  29 #ifndef _DHCPAGENT_IPC_H
  30 #define _DHCPAGENT_IPC_H
  31
  32 #include <sys/socket.h>
  33 #include <net/if.h>             /* LIFNAMSIZ */
  34 #include <stddef.h>
  35 #include <sys/types.h>
  36 #include <sys/time.h>
  37 #include <netinet/dhcp.h>
  38 #include <dhcp_impl.h>
  39
  40 /*
  41  * dhcpagent_ipc.[ch] comprise the interface used to perform
  42  * interprocess communication with the agent.  see dhcpagent_ipc.c for
  43  * documentation on how to use the exported functions.
  44  */
  45
  46 #ifdef  __cplusplus
  47 extern "C" {
  48 #endif
  49
  50 #define DHCP_AGENT_PATH         "/sbin/dhcpagent"
  51 #define DHCP_IPC_LISTEN_BACKLOG 30
  52 #define IPPORT_DHCPAGENT        4999
  53 #define DHCP_IPC_MAX_WAIT       15      /* max seconds to wait to start agent */
  54
  55 /*
  56  * return values which should be used by programs which talk to the
  57  * agent (for uniformity).
  58  */
  59
  60 #define DHCP_EXIT_SUCCESS       0
  61 #define DHCP_EXIT_FAILURE       2
  62 #define DHCP_EXIT_BADARGS       3
  63 #define DHCP_EXIT_TIMEOUT       4
  64 #define DHCP_EXIT_SYSTEM        6
  65
  66 /*
  67  * opaque types for requests and replies.  users of this api do not
  68  * need to understand their contents.
  69  */
  70
  71 typedef struct dhcp_ipc_request dhcp_ipc_request_t;
  72 typedef struct dhcp_ipc_reply   dhcp_ipc_reply_t;
  73
  74 /* payloads that can be passed in a request or reply */
  75
  76 typedef enum {
  77         DHCP_TYPE_OPTION,
  78         DHCP_TYPE_STATUS,
  79         DHCP_TYPE_OPTNUM,
  80         DHCP_TYPE_NONE
  81 } dhcp_data_type_t;
  82
  83 /*
  84  * requests that can be sent to the agent
  85  *
  86  * code in dhcpagent relies on the numeric values of these
  87  * requests -- but there's no sane reason to change them anyway.
  88  *
  89  * If any commands are changed, added, or removed, see the ipc_typestr[]
  90  * array in dhcpagent_ipc.c.
  91  */
  92
  93 typedef enum {
  94         DHCP_DROP,      DHCP_EXTEND,  DHCP_PING,    DHCP_RELEASE,
  95         DHCP_START,     DHCP_STATUS,  DHCP_INFORM,  DHCP_GET_TAG,
  96         DHCP_NIPC,      /* number of supported requests */
  97         DHCP_PRIMARY = 0x100,
  98         DHCP_V6 = 0x200
  99 } dhcp_ipc_type_t;
 100
 101 /* structure passed with the DHCP_GET_TAG request */
 102
 103 typedef struct {
 104         uint_t          category;
 105         uint_t          code;
 106         uint_t          size;
 107 } dhcp_optnum_t;
 108
 109 #define DHCP_IPC_CMD(type)      ((type) & 0x00ff)
 110 #define DHCP_IPC_FLAGS(type)    ((type) & 0xff00)
 111
 112 /* special timeout values for dhcp_ipc_make_request() */
 113
 114 #define DHCP_IPC_WAIT_FOREVER   (-1)
 115 #define DHCP_IPC_WAIT_DEFAULT   (-2)
 116
 117 /*
 118  * errors that can be returned from the provided functions.
 119  * note: keep in sync with dhcp_ipc_strerror()
 120  */
 121
 122 enum {
 123         /* System call errors must be kept contiguous */
 124         DHCP_IPC_SUCCESS,       DHCP_IPC_E_SOCKET,      DHCP_IPC_E_FCNTL,
 125         DHCP_IPC_E_READ,        DHCP_IPC_E_ACCEPT,      DHCP_IPC_E_CLOSE,
 126         DHCP_IPC_E_BIND,        DHCP_IPC_E_LISTEN,      DHCP_IPC_E_MEMORY,
 127         DHCP_IPC_E_CONNECT,     DHCP_IPC_E_WRITEV,      DHCP_IPC_E_POLL,
 128
 129         /* All others follow */
 130         DHCP_IPC_E_TIMEOUT,     DHCP_IPC_E_SRVFAILED,   DHCP_IPC_E_EOF,
 131         DHCP_IPC_E_INVIF,       DHCP_IPC_E_INT,         DHCP_IPC_E_PERM,
 132         DHCP_IPC_E_OUTSTATE,    DHCP_IPC_E_PEND,        DHCP_IPC_E_BOOTP,
 133         DHCP_IPC_E_CMD_UNKNOWN, DHCP_IPC_E_UNKIF,       DHCP_IPC_E_PROTO,
 134         DHCP_IPC_E_FAILEDIF,    DHCP_IPC_E_NOPRIMARY,   DHCP_IPC_E_DOWNIF,
 135         DHCP_IPC_E_NOIPIF,      DHCP_IPC_E_NOVALUE,     DHCP_IPC_E_RUNNING
 136 };
 137
 138 /*
 139  * low-level public dhcpagent ipc functions -- these are for use by
 140  * programs that need to communicate with the dhcpagent.  these will
 141  * remain relatively stable.
 142  */
 143
 144 extern const char       *dhcp_ipc_strerror(int);
 145 extern dhcp_ipc_request_t *dhcp_ipc_alloc_request(dhcp_ipc_type_t, const char *,
 146                             const void *, uint32_t, dhcp_data_type_t);
 147 extern void             *dhcp_ipc_get_data(dhcp_ipc_reply_t *, size_t *,
 148                             dhcp_data_type_t *);
 149 extern int              dhcp_ipc_make_request(dhcp_ipc_request_t *,
 150                             dhcp_ipc_reply_t **, int32_t);
 151 extern const char       *dhcp_ipc_type_to_string(dhcp_ipc_type_t);
 152
 153 /*
 154  * high-level public dhcpagent ipc functions
 155  */
 156
 157 extern int              dhcp_ipc_getinfo(dhcp_optnum_t *, DHCP_OPT **, int32_t);
 158
 159 /*
 160  * private dhcpagent ipc "server side" functions -- these are only for
 161  * use by dhcpagent(1M) and are subject to change.
 162  */
 163
 164 extern int              dhcp_ipc_init(int *);
 165 extern int              dhcp_ipc_accept(int, int *, int *);
 166 extern int              dhcp_ipc_recv_request(int, dhcp_ipc_request_t **, int);
 167 extern dhcp_ipc_reply_t *dhcp_ipc_alloc_reply(dhcp_ipc_request_t *, int,
 168                             const void *, uint32_t, dhcp_data_type_t);
 169 extern int              dhcp_ipc_send_reply(int, dhcp_ipc_reply_t *);
 170 extern int              dhcp_ipc_close(int);
 171
 172 /*
 173  * values for if_state in the dhcp_status_t
 174  *
 175  * code in this library and dhcpagent rely on the numeric values of these
 176  * requests -- but there's no sane reason to change them anyway.
 177  */
 178
 179 typedef enum {
 180         INIT,                           /* nothing done yet */
 181         SELECTING,                      /* sent DISCOVER, waiting for OFFERs */
 182         REQUESTING,                     /* sent REQUEST, waiting for ACK/NAK */
 183         PRE_BOUND,                      /* have ACK, setting up interface */
 184         BOUND,                          /* have a valid lease */
 185         RENEWING,                       /* have lease, but trying to renew */
 186         REBINDING,                      /* have lease, but trying to rebind */
 187         INFORMATION,                    /* sent INFORM, received ACK */
 188         INIT_REBOOT,                    /* attempt to use cached ACK/Reply */
 189         ADOPTING,                       /* attempting to adopt */
 190         INFORM_SENT,                    /* sent INFORM, awaiting ACK */
 191         DECLINING,                      /* sent v6 Decline, awaiting Reply */
 192         RELEASING,                      /* sent v6 Release, awaiting Reply */
 193         DHCP_NSTATES                    /* total number of states */
 194 } DHCPSTATE;
 195
 196 /* values for if_dflags in the dhcp_status_t */
 197
 198 #define DHCP_IF_PRIMARY         0x0100  /* interface is primary interface */
 199 #define DHCP_IF_BUSY            0x0200  /* asynchronous command pending */
 200 #define DHCP_IF_BOOTP           0x0400  /* interface is using bootp */
 201 #define DHCP_IF_REMOVED         0x0800  /* interface is going away */
 202 #define DHCP_IF_FAILED          0x1000  /* interface configuration problem */
 203 #define DHCP_IF_V6              0x2000  /* DHCPv6 interface */
 204
 205 /*
 206  * structure passed with the DHCP_STATUS replies
 207  *
 208  * when parsing a dhcp_status_t, `version' should always be checked
 209  * if there is a need to access any fields which were not defined in
 210  * version 1 of this structure.
 211  *
 212  * as new fields are added to the dhcp_status_t, they should be
 213  * appended to the structure and the version number incremented.
 214  */
 215
 216 typedef struct dhcp_status {
 217         uint8_t         version;        /* version of this structure */
 218
 219         char            if_name[LIFNAMSIZ];
 220         DHCPSTATE       if_state;       /* state of interface; see above */
 221
 222         time_t          if_began;       /* time lease began (absolute) */
 223         time_t          if_t1;          /* renewing time (absolute) */
 224         time_t          if_t2;          /* rebinding time (absolute) */
 225         time_t          if_lease;       /* lease expiration time (absolute) */
 226
 227         uint16_t        if_dflags;      /* DHCP flags on this if; see above */
 228
 229         /*
 230          * these three fields are initially zero, and get incremented
 231          * as if_state goes from INIT -> BOUND (or INIT ->
 232          * INFORMATION).  if and when the interface moves to the
 233          * RENEWING state, these fields are reset, so they always
 234          * either indicate the number of packets sent, received, and
 235          * declined while obtaining the current lease (if BOUND), or
 236          * the number of packets sent, received, and declined while
 237          * attempting to obtain a future lease (if any other state).
 238          */
 239
 240         uint32_t        if_sent;
 241         uint32_t        if_recv;
 242         uint32_t        if_bad_offers;
 243 } dhcp_status_t;
 244
 245 #define DHCP_STATUS_VER         1       /* current version of dhcp_status_t */
 246 #define DHCP_STATUS_VER1_SIZE   (offsetof(dhcp_status_t, if_bad_offers) + \
 247                                     sizeof (uint32_t))
 248
 249 /*
 250  * the remainder of this file contains implementation-specific
 251  * artifacts which may change. note that a `dhcp_ipc_request_t' and a
 252  * `dhcp_ipc_reply_t' are incomplete types as far as consumers of this
 253  * api are concerned.  use these details at your own risk.
 254  */
 255
 256 typedef hrtime_t dhcp_ipc_id_t;
 257
 258 /*
 259  * note: the first 4 fields of the dhcp_ipc_request_t and dhcp_ipc_reply_t
 260  *       are intentionally identical; code in dhcpagent_ipc.c counts on it!
 261  *
 262  * we pack these structs to ensure that their lengths will be identical between
 263  * 32-bit and 64-bit executables.
 264  */
 265
 266 #pragma pack(4)
 267
 268 struct  dhcp_ipc_request {
 269         dhcp_ipc_type_t  message_type;  /* type of request */
 270         dhcp_ipc_id_t    ipc_id;        /* per-socket unique request id */
 271         dhcp_data_type_t data_type;     /* type of payload */
 272         uint32_t         data_length;   /* size of actual data in the buffer */
 273         char             ifname[LIFNAMSIZ];
 274         int32_t          timeout;       /* timeout in seconds */
 275         uchar_t          buffer[1];     /* dynamically extended */
 276 };
 277
 278 struct  dhcp_ipc_reply {
 279         dhcp_ipc_type_t  message_type;  /* same message type as request */
 280         dhcp_ipc_id_t    ipc_id;        /* same id as request */
 281         dhcp_data_type_t data_type;     /* type of payload */
 282         uint32_t         data_length;   /* size of actual data in the buffer */
 283         uint32_t         return_code;   /* did the request succeed? */
 284         uchar_t          buffer[1];     /* dynamically extended */
 285 };
 286
 287 #pragma pack()
 288
 289 #define DHCP_IPC_REPLY_SIZE     offsetof(dhcp_ipc_reply_t, buffer)
 290 #define DHCP_IPC_REQUEST_SIZE   offsetof(dhcp_ipc_request_t, buffer)
 291
 292 #define DHCP_IPC_DEFAULT_WAIT   120     /* seconds */
 293
 294 #ifdef  __cplusplus
 295 }
 296 #endif
 297
 298 #endif  /* _DHCPAGENT_IPC_H */