boolean_t
set_start_timer(dhcp_smach_t *dsmp)
{
if (dsmp->dsm_start_timer != -1)
return (B_TRUE);
dsmp->dsm_start_timer = iu_schedule_timer_ms(tq,
lrand48() % DHCP_SELECT_WAIT, dhcp_start, dsmp);
if (dsmp->dsm_start_timer == -1)
return (B_FALSE);
hold_smach(dsmp);
return (B_TRUE);
}
/* ARGSUSED */
static void
ipc_event(iu_eh_t *ehp, int fd, short events, iu_event_id_t id, void *arg)
{
dhcp_ipc_request_t *request;
struct ifslist *ifsp, *primary_ifsp;
int error, is_priv = (int)arg;
PKT_LIST *plp[2];
dhcp_ipc_type_t cmd;
(void) iu_unregister_event(eh, id, NULL);
if (dhcp_ipc_recv_request(fd, &request, DHCP_IPC_REQUEST_WAIT) != 0) {
dhcpmsg(MSG_ERROR, "ipc_event: dhcp_ipc_recv_request failed");
(void) dhcp_ipc_close(fd);
return;
}
cmd = DHCP_IPC_CMD(request->message_type);
if (cmd >= DHCP_NIPC) {
send_error_reply(request, DHCP_IPC_E_CMD_UNKNOWN, &fd);
return;
}
/* return EPERM for any of the privileged actions */
if (!is_priv) {
switch (cmd) {
case DHCP_STATUS:
case DHCP_PING:
case DHCP_GET_TAG:
break;
default:
dhcpmsg(MSG_WARNING, "ipc_event: privileged ipc "
"command (%i) attempted on %s", cmd,
request->ifname);
send_error_reply(request, DHCP_IPC_E_PERM, &fd);
return;
}
}
/*
* try to locate the ifs associated with this command. if the
* command is DHCP_START or DHCP_INFORM, then if there isn't
* an ifs already, make one (there may already be one from a
* previous failed attempt to START or INFORM). otherwise,
* verify the interface is still valid.
*/
ifsp = lookup_ifs(request->ifname);
switch (cmd) {
case DHCP_START: /* FALLTHRU */
case DHCP_INFORM:
/*
* it's possible that the interface already exists, but
* has been abandoned. usually in those cases we should
* return DHCP_IPC_E_UNKIF, but that makes little sense
* in the case of "start" or "inform", so just ignore
* the abandoned interface and start over anew.
*/
if (ifsp != NULL && verify_ifs(ifsp) == 0)
ifsp = NULL;
/*
* as part of initializing the ifs, insert_ifs()
* creates a DLPI stream at ifsp->if_dlpi_fd.
*/
if (ifsp == NULL) {
ifsp = insert_ifs(request->ifname, B_FALSE, &error);
if (ifsp == NULL) {
send_error_reply(request, error, &fd);
return;
}
}
break;
default:
if (ifsp == NULL) {
if (request->ifname[0] == '\0')
error = DHCP_IPC_E_NOPRIMARY;
else
error = DHCP_IPC_E_UNKIF;
send_error_reply(request, error, &fd);
return;
}
break;
}
if (verify_ifs(ifsp) == 0) {
send_error_reply(request, DHCP_IPC_E_UNKIF, &fd);
return;
}
if (ifsp->if_dflags & DHCP_IF_BOOTP) {
switch (cmd) {
case DHCP_EXTEND:
case DHCP_RELEASE:
case DHCP_INFORM:
send_error_reply(request, DHCP_IPC_E_BOOTP, &fd);
return;
default:
break;
}
}
/*
* verify that the interface is in a state which will allow the
* command. we do this up front so that we can return an error
* *before* needlessly cancelling an in-progress transaction.
*/
if (!ipc_cmd_allowed[ifsp->if_state][cmd]) {
send_error_reply(request, DHCP_IPC_E_OUTSTATE, &fd);
return;
}
if ((request->message_type & DHCP_PRIMARY) && is_priv) {
if ((primary_ifsp = lookup_ifs("")) != NULL)
primary_ifsp->if_dflags &= ~DHCP_IF_PRIMARY;
ifsp->if_dflags |= DHCP_IF_PRIMARY;
}
/*
* current design dictates that there can be only one
* outstanding transaction per interface -- this simplifies
* the code considerably and also fits well with RFC2131.
* it is worth classifying the different DHCP commands into
* synchronous (those which we will handle now and be done
* with) and asynchronous (those which require transactions
* and will be completed at an indeterminate time in the
* future):
*
* DROP: removes the agent's management of an interface.
* asynchronous as the script program may be invoked.
*
* PING: checks to see if the agent controls an interface.
* synchronous, since no packets need to be sent
* to the DHCP server.
*
* STATUS: returns information about the an interface.
* synchronous, since no packets need to be sent
* to the DHCP server.
*
* RELEASE: releases the agent's management of an interface
* and brings the interface down. asynchronous as
* the script program may be invoked.
*
* EXTEND: renews a lease. asynchronous, since the agent
* needs to wait for an ACK, etc.
*
* START: starts DHCP on an interface. asynchronous since
* the agent needs to wait for OFFERs, ACKs, etc.
*
* INFORM: obtains configuration parameters for an externally
* configured interface. asynchronous, since the
* agent needs to wait for an ACK.
*
* notice that EXTEND, INFORM, START, DROP and RELEASE are
* asynchronous. notice also that asynchronous commands may
* occur from within the agent -- for instance, the agent
* will need to do implicit EXTENDs to extend the lease. in
* order to make the code simpler, the following rules apply
* for asynchronous commands:
*
* there can only be one asynchronous command at a time per
* interface. the current asynchronous command is managed by
* the async_* api: async_start(), async_finish(),
* async_timeout(), async_cancel(), and async_pending().
* async_start() starts management of a new asynchronous
* command on an interface, which should only be done after
* async_pending() is called to check that there are no
* pending asynchronous commands on that interface. when the
* command is completed, async_finish() should be called. all
* asynchronous commands have an associated timer, which calls
* async_timeout() when it times out. if async_timeout()
* decides that the asynchronous command should be cancelled
* (see below), it calls async_cancel() to attempt
* cancellation.
*
* asynchronous commands started by a user command have an
* associated ipc_action which provides the agent with
* information for how to get in touch with the user command
* when the action completes. these ipc_action records also
* have an associated timeout which may be infinite.
* ipc_action_start() should be called when starting an
* asynchronous command requested by a user, which sets up the
* timer and keeps track of the ipc information (file
* descriptor, request type). when the asynchronous command
* completes, ipc_action_finish() should be called to return a
* command status code to the user and close the ipc
* connection). if the command does not complete before the
* timer fires, ipc_action_timeout() is called which closes
* the ipc connection and returns DHCP_IPC_E_TIMEOUT to the
* user. note that independent of ipc_action_timeout(),
* ipc_action_finish() should be called.
*
* on a case-by-case basis, here is what happens (per interface):
*
* o when an asynchronous command is requested, then
* async_pending() is called to see if there is already
* an asynchronous event. if so, the command does not
* proceed, and if there is an associated ipc_action,
* the user command is sent DHCP_IPC_E_PEND.
*
* o otherwise, the the transaction is started with
* async_start(). if the transaction is on behalf
* of a user, ipc_action_start() is called to keep
* track of the ipc information and set up the
* ipc_action timer.
*
* o if the command completes normally and before a
* timeout fires, then async_finish() is called.
* if there was an associated ipc_action,
* ipc_action_finish() is called to complete it.
*
* o if the command fails before a timeout fires, then
* async_finish() is called, and the interface is
* is returned to a known state based on the command.
* if there was an associated ipc_action,
* ipc_action_finish() is called to complete it.
*
* o if the ipc_action timer fires before command
* completion, then DHCP_IPC_E_TIMEOUT is returned to
* the user. however, the transaction continues to
* be carried out asynchronously.
*
* o if async_timeout() fires before command completion,
* then if the command was internal to the agent, it
* is cancelled. otherwise, if it was a user command,
* then if the user is still waiting for the command
* to complete, the command continues and async_timeout()
* is rescheduled.
*/
switch (cmd) {
case DHCP_DROP: /* FALLTHRU */
case DHCP_RELEASE: /* FALLTHRU */
case DHCP_EXTEND: /* FALLTHRU */
case DHCP_INFORM: /* FALLTHRU */
case DHCP_START:
/*
* if shutdown request has been received, send back an error.
*/
if (shutdown_started) {
send_error_reply(request, DHCP_IPC_E_OUTSTATE, &fd);
return;
}
if (async_pending(ifsp)) {
send_error_reply(request, DHCP_IPC_E_PEND, &fd);
return;
}
if (ipc_action_start(ifsp, request, fd) == 0) {
dhcpmsg(MSG_WARNING, "ipc_event: ipc_action_start "
"failed for %s", ifsp->if_name);
send_error_reply(request, DHCP_IPC_E_MEMORY, &fd);
return;
}
if (async_start(ifsp, cmd, B_TRUE) == 0) {
ipc_action_finish(ifsp, DHCP_IPC_E_MEMORY);
return;
}
break;
default:
break;
}
switch (cmd) {
case DHCP_DROP:
(void) script_start(ifsp, EVENT_DROP, dhcp_drop, NULL, NULL);
return;
case DHCP_EXTEND:
(void) dhcp_extending(ifsp);
break;
case DHCP_GET_TAG: {
dhcp_optnum_t optnum;
DHCP_OPT *opt = NULL;
boolean_t did_alloc = B_FALSE;
PKT_LIST *ack = ifsp->if_ack;
/*
* verify the request makes sense.
*/
if (request->data_type != DHCP_TYPE_OPTNUM ||
request->data_length != sizeof (dhcp_optnum_t)) {
send_error_reply(request, DHCP_IPC_E_PROTO, &fd);
return;
}
(void) memcpy(&optnum, request->buffer, sizeof (dhcp_optnum_t));
load_option:
switch (optnum.category) {
case DSYM_SITE: /* FALLTHRU */
case DSYM_STANDARD:
if (optnum.code <= DHCP_LAST_OPT)
opt = ack->opts[optnum.code];
break;
case DSYM_VENDOR:
/*
* the test against VS_OPTION_START is broken up into
* two tests to avoid compiler warnings under intel.
*/
if ((optnum.code > VS_OPTION_START ||
optnum.code == VS_OPTION_START) &&
optnum.code <= VS_OPTION_END)
opt = ack->vs[optnum.code];
break;
case DSYM_FIELD:
if (optnum.code + optnum.size > sizeof (PKT))
break;
/* + 2 to account for option code and length byte */
opt = malloc(optnum.size + 2);
if (opt == NULL) {
send_error_reply(request, DHCP_IPC_E_MEMORY,
&fd);
return;
}
did_alloc = B_TRUE;
opt->len = optnum.size;
opt->code = optnum.code;
(void) memcpy(&opt->value, (caddr_t)ack->pkt +
opt->code, opt->len);
break;
default:
send_error_reply(request, DHCP_IPC_E_PROTO, &fd);
return;
}
/*
* return the option payload, if there was one. the "+ 2"
* accounts for the option code number and length byte.
*/
if (opt != NULL) {
send_data_reply(request, &fd, 0, DHCP_TYPE_OPTION, opt,
opt->len + 2);
if (did_alloc)
free(opt);
return;
} else if (ack != ifsp->if_orig_ack) {
/*
* There wasn't any definition for the option in the
* current ack, so now retry with the original ack if
* the original ack is not the current ack.
*/
ack = ifsp->if_orig_ack;
goto load_option;
}
/*
* note that an "okay" response is returned either in
* the case of an unknown option or a known option
* with no payload. this is okay (for now) since
* dhcpinfo checks whether an option is valid before
* ever performing ipc with the agent.
*/
send_ok_reply(request, &fd);
return;
}
case DHCP_INFORM:
dhcp_inform(ifsp);
/* next destination: dhcp_acknak() */
return;
case DHCP_PING:
if (ifsp->if_dflags & DHCP_IF_FAILED)
send_error_reply(request, DHCP_IPC_E_FAILEDIF, &fd);
else
send_ok_reply(request, &fd);
return;
case DHCP_RELEASE:
(void) script_start(ifsp, EVENT_RELEASE, dhcp_release,
"Finished with lease.", NULL);
return;
case DHCP_START:
(void) canonize_ifs(ifsp);
/*
* if we have a valid hostconf lying around, then jump
* into INIT_REBOOT. if it fails, we'll end up going
* through the whole selecting() procedure again.
*/
error = read_hostconf(ifsp->if_name, plp, 2);
if (error != -1) {
ifsp->if_orig_ack = ifsp->if_ack = plp[0];
if (error > 1) {
/*
* Return indicated we had more than one packet
* second one is the original ack. Older
* versions of the agent wrote only one ack
* to the file, we now keep both the first
* ack as well as the last one.
*/
ifsp->if_orig_ack = plp[1];
}
dhcp_init_reboot(ifsp);
/* next destination: dhcp_acknak() */
return;
}
/*
* if not debugging, wait for a few seconds before
* going into SELECTING.
*/
if (debug_level == 0) {
if (iu_schedule_timer_ms(tq,
lrand48() % DHCP_SELECT_WAIT, dhcp_start, ifsp)
!= -1) {
hold_ifs(ifsp);
/* next destination: dhcp_start() */
return;
}
}
dhcp_selecting(ifsp);
/* next destination: dhcp_requesting() */
return;
case DHCP_STATUS: {
dhcp_status_t status;
status.if_began = monosec_to_time(ifsp->if_curstart_monosec);
if (ifsp->if_lease == DHCP_PERM) {
status.if_t1 = DHCP_PERM;
status.if_t2 = DHCP_PERM;
status.if_lease = DHCP_PERM;
} else {
status.if_t1 = status.if_began + ifsp->if_t1;
status.if_t2 = status.if_began + ifsp->if_t2;
status.if_lease = status.if_began + ifsp->if_lease;
}
status.version = DHCP_STATUS_VER;
status.if_state = ifsp->if_state;
status.if_dflags = ifsp->if_dflags;
status.if_sent = ifsp->if_sent;
status.if_recv = ifsp->if_received;
status.if_bad_offers = ifsp->if_bad_offers;
(void) strlcpy(status.if_name, ifsp->if_name, IFNAMSIZ);
send_data_reply(request, &fd, 0, DHCP_TYPE_STATUS, &status,
sizeof (dhcp_status_t));
return;
}
default:
return;
}
}
iu_timer_id_t
iu_schedule_timer(iu_tq_t *tq, uint32_t sec, iu_tq_callback_t *callback,
void *arg)
{
return (iu_schedule_timer_ms(tq, sec * MILLISEC, callback, arg));
}
