connections.c 20 KB
Newer Older
Linus Tolke Y's avatar
Linus Tolke Y committed
1
/*
2
 * $Id: connections.c,v 0.90 2002/11/25 16:27:37 ceder Exp $
Per Cederqvist's avatar
Per Cederqvist committed
3
 * Copyright (C) 1991-2002  Lysator Academic Computer Association.
Linus Tolke Y's avatar
Linus Tolke Y committed
4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
 *
 * This file is part of the LysKOM server.
 * 
 * LysKOM is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by 
 * the Free Software Foundation; either version 1, or (at your option) 
 * any later version.
 * 
 * LysKOM is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with LysKOM; see the file COPYING.  If not, write to
 * Lysator, c/o ISY, Linkoping University, S-581 83 Linkoping, SWEDEN,
 * or the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, 
 * MA 02139, USA.
 *
 * Please mail bug reports to bug-lyskom@lysator.liu.se. 
 */
Per Cederqvist's avatar
Per Cederqvist committed
25 26 27 28 29 30 31 32
/*
 * connections.c
 *
 * Denna fil inneh}ller niv}n ovanf|r isc.
 *
 * Created by Willf|r 31/3-90. Mostly written by ceder.
 */

David Byers's avatar
David Byers committed
33 34 35 36 37

#ifdef HAVE_CONFIG_H
#  include <config.h>
#endif

Per Cederqvist's avatar
Per Cederqvist committed
38
#include <errno.h>
Per Cederqvist's avatar
Per Cederqvist committed
39
#include <stdio.h>
Per Cederqvist's avatar
Per Cederqvist committed
40
#include <setjmp.h>
Per Cederqvist's avatar
Per Cederqvist committed
41 42 43
#ifdef HAVE_STRING_H
#  include <string.h>
#endif
Per Cederqvist's avatar
Per Cederqvist committed
44
#include <sys/types.h>
Per Cederqvist's avatar
Per Cederqvist committed
45
#include <sys/stat.h>
Per Cederqvist's avatar
Per Cederqvist committed
46
#ifdef TIME_WITH_SYS_TIME
47 48
#  include <sys/time.h>
#  include <time.h>
Per Cederqvist's avatar
Per Cederqvist committed
49
#else
50 51 52 53 54
#  ifdef HAVE_SYS_TIME_H
#    include <sys/time.h>
#  else
#    include <time.h>
#  endif
Per Cederqvist's avatar
Per Cederqvist committed
55
#endif
56
#include <sys/socket.h>
57
#include <signal.h>
Per Cederqvist's avatar
Per Cederqvist committed
58

59
#include "ldifftime.h"
Per Cederqvist's avatar
Per Cederqvist committed
60
#include "misc-types.h"
61
#include "s-string.h"
Per Cederqvist's avatar
Per Cederqvist committed
62
#include "kom-types.h"
63
#include "kom-memory.h"
Per Cederqvist's avatar
Per Cederqvist committed
64
#include "debug.h"
65
#include "isc-interface.h"
Per Cederqvist's avatar
Per Cederqvist committed
66
#include "com.h"
67
#include "async.h"
Per Cederqvist's avatar
Per Cederqvist committed
68
#include "connections.h"
Per Cederqvist's avatar
Per Cederqvist committed
69
#include "internal-connections.h"
Per Cederqvist's avatar
Per Cederqvist committed
70
#include "prot-a-parse-arg.h"
Per Cederqvist's avatar
Per Cederqvist committed
71 72 73 74 75
#include "log.h"
#include "lyskomd.h"
#include "services.h"
#include "isc-parse.h"
#include "prot-a.h"
76
#include "prot-a-parse.h"
Per Cederqvist's avatar
Per Cederqvist committed
77 78 79 80
#include "server/smalloc.h"
#include "end-of-atomic.h"
#include "send-async.h"
#include "cache.h"
81
#include "rfc931.h"
82
#include "param.h"
David Byers's avatar
David Byers committed
83
#include "kom-config.h"
84
#include "kom-errno.h"
Per Cederqvist's avatar
Per Cederqvist committed
85
#include "sigflags.h"
Per Cederqvist's avatar
Per Cederqvist committed
86
#include "server-time.h"
87
#include "aux-items.h"
88
#include "eintr.h"
Per Cederqvist's avatar
Per Cederqvist committed
89

Per Cederqvist's avatar
Per Cederqvist committed
90
IscMaster      * kom_server_mcb    = NULL;
Per Cederqvist's avatar
Per Cederqvist committed
91 92
Connection     * active_connection = NULL;

Per Cederqvist's avatar
Per Cederqvist committed
93 94 95 96 97 98
/*
 * This is set TRUE when the server should be closed. It is checked
 * each time around the main loop. It is set if someone with enough
 * privileges issues a `shutdown', or of lyskomd receives a SIGHUP.
 * This not an abort: all data is saved before we exit.
 */
99
volatile sig_atomic_t go_and_die = 0;
Per Cederqvist's avatar
Per Cederqvist committed
100 101

/*
102 103
 * The lyskomd server will dump some statistics when it receives a
 * SIGUSR1 signal.  The signal handler sets the do_statistics flag.
Per Cederqvist's avatar
Per Cederqvist committed
104
 */
105
volatile sig_atomic_t do_statistics = 0;
Per Cederqvist's avatar
Per Cederqvist committed
106 107 108 109 110 111 112 113

jmp_buf 	 parse_env;


const Fnc_descriptor fnc_defs[]={
#include "fnc-def-init.incl"
};

114
const int num_fnc_defs = sizeof (fnc_defs) / sizeof (Fnc_descriptor);
115

Per Cederqvist's avatar
Per Cederqvist committed
116
unsigned long service_statistics[sizeof (fnc_defs) / sizeof (Fnc_descriptor)];
Per Cederqvist's avatar
Per Cederqvist committed
117 118 119 120 121

BUGDECL;



Per Cederqvist's avatar
Per Cederqvist committed
122
static void
Per Cederqvist's avatar
Per Cederqvist committed
123 124 125
logout_client(Connection *cp)
{
    Connection *real_active_connection;
126
    int ret;
Per Cederqvist's avatar
Per Cederqvist committed
127 128 129

    if ( active_connection != NULL )
    {
David Byers's avatar
David Byers committed
130
	kom_log("BUGCHK: logout_client(%ld): connection %ld is active.\n",
Per Cederqvist's avatar
Per Cederqvist committed
131 132 133 134 135 136 137 138 139
	    cp->session_no, active_connection->session_no);
    }
    
    switch (cp->magic)
    {
    case CONN_MAGIC_ALLOC:
        break;

    case CONN_MAGIC_FREE:
David Byers's avatar
David Byers committed
140
	kom_log("LOGOUT_CLIENT: Trying to free freed Connection - ignored!\n");
Per Cederqvist's avatar
Per Cederqvist committed
141 142 143 144 145 146 147 148
	return;

    default:
	restart_kom("LOGOUT_CLIENT: Bad magic number\n");
    }

    if ( cp->pers_no != 0 )
    {
149 150 151 152 153 154 155 156 157 158 159 160
	int ctr = 0;

	if (active_connection != NULL)
	{
	    kom_log("WNG: logout_client(): active_connection != NULL\n");
	    if (ctr < 100)
		ctr++;
	    else
		kom_log("WNG: won't log the above message more\n");
	}

	real_active_connection = active_connection;
Per Cederqvist's avatar
Per Cederqvist committed
161 162 163 164
	active_connection = cp;
	logout();
	active_connection = real_active_connection;
    }
165 166
    else
    {
167
#if 0
168
	/* FIXME (bug 908): send a new async here instead.  This causes the
169 170
	   elisp client to say that a secret (or unknown) person has
	   left the system.  */
171
        async_logout( 0, cp->session_no );
172
#endif
173
    }
Per Cederqvist's avatar
Per Cederqvist committed
174 175 176 177 178 179 180 181 182 183 184 185 186 187

    switch(cp->protocol)
    {
    case 0:			/* Hasn't yet allocated any protocol. */
	break;
	
    case 'A':
	prot_a_destruct(cp);
	break;
	
    default:
	restart_kom("logout_client(): Bad protocol.\n");
    }

188 189
    ret = isc_destroy(kom_server_mcb, cp->isc_session);
    if (ret < 0)
David Byers's avatar
David Byers committed
190
	kom_log("logout_client(): isc_destroyed returned %d\n", ret);
191
    cp->isc_session = NULL;
Per Cederqvist's avatar
Per Cederqvist committed
192 193 194 195

    kill_client(cp);		/* Free the Connection */
}

Per Cederqvist's avatar
Per Cederqvist committed
196 197 198 199 200 201 202 203 204 205 206 207 208 209
/*
 * This function is part of the shutdown tidy-up sequence.
 */
void
logout_all_clients(void)
{
    Session_no sess = 0;
    Connection *conn;
    
    while ( (sess = traverse_connections (sess)) != 0)
    {
	conn = get_conn_by_number (sess);

	if ( conn == NULL )
210
	    restart_kom("logout_all_clients(): cant get session %ld.\n",
Per Cederqvist's avatar
Per Cederqvist committed
211 212 213 214 215 216
			sess);
	else
	    logout_client (conn);
    }

    if ( traverse_connections (0) != 0)
217
	restart_kom("logout_all_clients(): traverse_connections(0) == %ld.\n",
Per Cederqvist's avatar
Per Cederqvist committed
218 219 220 221
		    traverse_connections(0));
}

    
Per Cederqvist's avatar
Per Cederqvist committed
222 223 224 225 226 227 228 229
    

    
/*
 * Call a function in services.c. A pointer to the result is returned.
 * The pointer points to static data which is overwritten on each call.
 */
static Success
230 231
call_function(Connection *client,
	      union result_holder *res)
Per Cederqvist's avatar
Per Cederqvist committed
232 233 234 235 236
{
    Success	status=FAILURE;	/* OK if the call was successful. */

    if ( active_connection != NULL )
    {
237
	kom_log("call_function(%ld): active_connection = %ld\n",
Per Cederqvist's avatar
Per Cederqvist committed
238 239
	    client->session_no, active_connection->session_no);
    }
240 241 242

    if (client->function == illegal_fnc) 
    {
243
        err_stat = 0;
244 245 246 247
	kom_errno = KOM_NOT_IMPL;
	return FAILURE;
    }

Per Cederqvist's avatar
Per Cederqvist committed
248 249
    active_connection = client;

250
    service_statistics[client->function_index]++;
Per Cederqvist's avatar
Per Cederqvist committed
251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273

#include "call-switch.incl"

    active_connection = NULL;

    return status;
}


static void
parse_packet(Connection *client)
{
    if ( client->protocol == '\0' ) /* Not known yet. */
    {
	client->protocol = parse_char(client);
	switch(client->protocol)
	{
	case 'A':
	    prot_a_init(client);
	    break;

	default:
	    client->protocol = '\0';
274 275
	    isc_puts("%%LysKOM unsupported protocol.\n", client->isc_session);
	    isc_flush(client->isc_session);
Per Cederqvist's avatar
Per Cederqvist committed
276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306
	    BUG(("%%%%Unsupported protocol.\n"));
	    longjmp(parse_env, ISC_LOGOUT);
	}
    }

    switch(client->protocol)
    {
    case 'A':
	prot_a_parse_packet(client);
	break;

    default:
	restart_kom("parse_packet(): Bad protocol.\n");
	break;
    }
}

/*
 * Free all parsed areas which are no longer needed. Re-initialize all
 * parse_pos fields so that the parse will expect a new function.
 *
 * This function is called
 *	when a parse error occurs
 *	when a parse is complete and the function has executed.
 */
static void
free_parsed(Connection *client)
{
    s_clear(&client->c_string0);
    s_clear(&client->c_string1);
    client->string0 = EMPTY_STRING; /* So that no one frees it. */
David Byers's avatar
David Byers committed
307 308 309
    sfree(client->misc_info_list.misc);
    client->misc_info_list.misc = 0;
    client->misc_info_list.no_of_misc = 0;
310
    s_clear(&client->aux_item.data);
311
    s_clear(&client->dummy_aux_item.data);
Per Cederqvist's avatar
Per Cederqvist committed
312 313
    sfree( client->c_local_text_no_p);
    client->c_local_text_no_p = NULL;
314 315 316
    sfree(client->read_range_list.ranges);
    client->read_range_list.ranges = NULL;
    client->read_range_list.length = 0;
Per Cederqvist's avatar
Per Cederqvist committed
317 318
    client->parse_pos = 0;
    client->fnc_parse_pos = 0;
319
    client->array_parse_index = 0;
David Byers's avatar
David Byers committed
320
    client->array_parse_parsed_length = 0;
Per Cederqvist's avatar
Per Cederqvist committed
321 322 323
    client->array_parse_pos = 0;
    client->struct_parse_pos = 0;
    client->string_parse_pos = 0;
David Byers's avatar
David Byers committed
324 325 326
    client->hunt_parse_pos = 0;
    client->array_hunt_num = 0;
    client->array_hunt_depth = 0;
327 328 329
    sfree(client->num_list.data);
    client->num_list.data = NULL;
    client->num_list.length = 0;
330 331
    free_aux_item_list(&client->aux_item_list);
    client->info.highest_aux_no = 0;
Per Cederqvist's avatar
Per Cederqvist committed
332 333 334 335 336 337 338
}

/*
 * Send a reply to a call.
 */
static void
reply(Connection *client,
339 340
      Success status,
      union result_holder *result)
Per Cederqvist's avatar
Per Cederqvist committed
341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363
{
    switch(client->protocol)
    {
    case 'A':
	prot_a_reply(client, status, result);
	break;

    default:
	restart_kom("reply(): Bad protocol.\n");
	break;
    }
}


/*
 * Try to parse enough data from client->unparsed to call a function.
 * If more data is needed set client->more_to_parse to FALSE.
 */
static void
parse_unparsed(Connection *client)
{
    String        tmp_str = EMPTY_STRING;
    Success       status;
364
    union result_holder result;
Per Cederqvist's avatar
Per Cederqvist committed
365 366 367 368 369 370 371 372 373 374 375 376 377 378 379
        
    switch ( setjmp(parse_env) )
    {
    case 0 :
	/* Parse message. If message is complete call function and reply. */
	parse_packet(client);
	status = call_function(client, &result);
	reply(client, status, &result);
	free_parsed(client);
	end_of_atomic(FALSE);
	break;

    case ISC_PROTOCOL_ERR:
	s_clear(&client->string0);
	free_parsed(client);
380 381
	isc_puts("%% LysKOM protocol error.\n", client->isc_session);
	isc_flush(client->isc_session);
Per Cederqvist's avatar
Per Cederqvist committed
382 383 384 385 386 387 388 389 390 391 392 393
	BUG(("%%%% Protocol error.\n"));
	s_clear(&client->unparsed);
	client->first_to_parse = 0;
	client->more_to_parse = FALSE;
	end_of_atomic(FALSE);
	break;

    case ISC_MSG_INCOMPLETE:
	client->more_to_parse = FALSE;
	break;

    case ISC_LOGOUT:
394
	add_to_kill_list(client);
Per Cederqvist's avatar
Per Cederqvist committed
395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433
	break;
    }
    
    /* Delete the parsed part of 'unparsed' */
    
    if ( s_substr(&tmp_str, client->unparsed,
		  client->first_to_parse, END_OF_STRING) != OK )
	restart_kom("parse_unparsed: s_substr\n");

    s_clear(&client->unparsed);
    client->unparsed = tmp_str;
    client->first_to_parse = 0;
}


/*
 * There is a message in the event. Parse it.
 */
static void
parse_message(Connection *cp, String tmp_str)
{
    VBUGSTR(tmp_str);

    cp->more_to_parse = TRUE;
    
    if ( s_strcat(&cp->unparsed, tmp_str) != OK )
	restart_kom("parse_message(): s_strcat\n");

    tmp_str = EMPTY_STRING;
    
    /* Parse this packet, but leave the last token if it isn't complete. */

    parse_unparsed(cp);

    return;
}


/*
434
 * parse data in client->unparsed if there
Per Cederqvist's avatar
Per Cederqvist committed
435 436 437
 * is data that has not yet been taken care of. Return TRUE
 * if there was no data to take care of.
 */
Per Cederqvist's avatar
Per Cederqvist committed
438 439
static Bool
parse_forgotten(void)
Per Cederqvist's avatar
Per Cederqvist committed
440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458
{
    Bool flg = FALSE;			/* Was there anything? */
    Connection *ci;
    Session_no session_no = 0;

    if ( traverse_connections(0) == 0 )
	return TRUE;

    while ( ( session_no = traverse_connections( session_no ) ) != 0 )
    {
	ci = get_conn_by_number (session_no);

	if ( ci->more_to_parse )
	{
	    parse_unparsed(ci);
	    flg = TRUE;
	}
    }

459
    return flg ? FALSE : TRUE;
Per Cederqvist's avatar
Per Cederqvist committed
460 461 462 463 464
}


/* Return 1 if the named file exists, 0 otherwise */
static int
Per Cederqvist's avatar
Per Cederqvist committed
465
fexists(const char *filename)
Per Cederqvist's avatar
Per Cederqvist committed
466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483
{
    struct stat buf;
    int code;
  
    code = !stat(filename, &buf);
    errno = 0;

    return code;
}


void
dump_statistics(void)
{
    static time_t last_dump = NO_TIME;
    int i;
    FILE *fp;

484
    if ((fp = i_fopen(param.statistic_name, "a")) == NULL)
Per Cederqvist's avatar
Per Cederqvist committed
485
    {
486 487
	kom_log("dump_statistics(): can't open file %s\n",
		param.statistic_name);
Per Cederqvist's avatar
Per Cederqvist committed
488 489 490 491 492 493
	return;
    }

    if (last_dump == NO_TIME)
    {
	fprintf(fp, "RESTART\n");
Per Cederqvist's avatar
Per Cederqvist committed
494
	last_dump = current_time;
Per Cederqvist's avatar
Per Cederqvist committed
495 496
    }
    
Per Cederqvist's avatar
Per Cederqvist committed
497 498
    fprintf(fp, "TIME: %s", ctime(&current_time));
    fprintf(fp, "SECONDS: %d\n", (int)ldifftime(current_time, last_dump));
Per Cederqvist's avatar
Per Cederqvist committed
499
    fprintf(fp, "STATISTICS:");
500 501 502 503 504

    /* The last entry corresponds to the dummy entry that is used to
       skip arguments to unimplemented requests.  Skip that, since it
       contains no useful statistics.  */
    for (i = 0; i < num_fnc_defs - 1; i++)
Per Cederqvist's avatar
Per Cederqvist committed
505
    {
506
	fprintf(fp, " %d:%lu", fnc_defs[i].function, service_statistics[i]);
Per Cederqvist's avatar
Per Cederqvist committed
507 508 509 510
	service_statistics[i]=0;
    }

    fprintf(fp, "\n");
511
    i_fclose(fp);
Per Cederqvist's avatar
Per Cederqvist committed
512

Per Cederqvist's avatar
Per Cederqvist committed
513
    last_dump = current_time;
Per Cederqvist's avatar
Per Cederqvist committed
514 515
}

516 517 518 519 520 521 522 523 524
/* List of connections to kill. */

Session_no *kill_list = NULL;
int kill_list_size = 0;

/* Schedule this client for termination. */
void
add_to_kill_list(Connection *conn)
{
Per Cederqvist's avatar
Per Cederqvist committed
525 526 527
    int i;

    for (i = 0; i < kill_list_size; i++)
528
	if (kill_list[i] == conn->session_no)
Per Cederqvist's avatar
Per Cederqvist committed
529
	{
David Byers's avatar
David Byers committed
530
	    kom_log("add_to_kill_list(%ld): already present as %d of %d.\n",
Per Cederqvist's avatar
Per Cederqvist committed
531 532 533 534
		conn->session_no, i, kill_list_size);
	    return;
	}

535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550
    if (kill_list == NULL)
    {
	if (kill_list_size != 0)
	    restart_kom("add_to_kill_list(): size = %d\n", kill_list_size);

	kill_list_size = 1;
	kill_list = smalloc(sizeof(Session_no));
    }
    else
    {
	kill_list_size++;
	kill_list = srealloc(kill_list, kill_list_size * sizeof(Session_no));
    }

    kill_list[kill_list_size-1] = conn->session_no;
}
Per Cederqvist's avatar
Per Cederqvist committed
551

552 553 554 555 556 557 558 559

void
dump_connections(void)
{
    Session_no s;
    Connection *conn;
    FILE *fp;

560
    if ((fp = i_fopen(param.connection_status_file_tmp, "w")) == NULL)
561
    {
562 563
	kom_log("dump_connections(): can't open file %s: %s\n",
		param.connection_status_file_tmp, strerror(errno));
564 565 566 567 568 569 570 571 572 573
	return;
    }

    for (s = 0; (s = traverse_connections(s)) != 0;)
    {
	conn = get_conn_by_number(s);
	fprintf(fp, "%d %lu %s\n", conn->isc_session->fd, conn->session_no,
		conn->peer);
    }

574 575 576 577 578 579
    if (fflush(fp) != 0)
	kom_log("dump_connections(): fflush() says an error has occured.\n");
	
    if (ferror(fp))
	kom_log("dump_connections(): ferror() says an error has occured.\n");

580
    if (i_fclose(fp) < 0)
581 582 583 584 585
    {
	kom_log("dump_connections(): fclose failed: %s (ignored)\n",
		strerror(errno));
    }

586
    errno = 0;
587 588
    if (i_rename(param.connection_status_file_tmp,
		 param.connection_status_file) < 0)
589
    {
590
	kom_log("dump_connections(): can't rename %s to %s: %s\n",
591
		param.connection_status_file_tmp,
592 593
		param.connection_status_file,
		strerror(errno));
594 595 596 597
    }
}


Per Cederqvist's avatar
Per Cederqvist committed
598 599 600 601 602 603 604
/*
 * check_kill_flg must NEVER be called inside an atomic call!
 */
static void
check_kill_flg(void)
{
    Connection *conn;
605
    Bool changed = FALSE;
Per Cederqvist's avatar
Per Cederqvist committed
606 607 608

    if ( active_connection != NULL )
    {
609
	restart_kom("check_kill_flg: active_connection == %ld",
Per Cederqvist's avatar
Per Cederqvist committed
610 611 612
		    active_connection->session_no);
    }

613
    while (kill_list_size > 0)
Per Cederqvist's avatar
Per Cederqvist committed
614
    {
615 616 617
	--kill_list_size;
	conn = get_conn_by_number (kill_list[kill_list_size]);
	if (conn == NULL)
Per Cederqvist's avatar
Per Cederqvist committed
618
	{
David Byers's avatar
David Byers committed
619
	    kom_log("check_kill_flg(): Connection %ld doesn't exist.\n",
620 621 622 623 624 625
		kill_list[kill_list_size]);
	}
	else
	{
	    logout_client (conn);
	    end_of_atomic (FALSE);
626
	    changed = TRUE;
Per Cederqvist's avatar
Per Cederqvist committed
627 628
	}
    }
629

630 631 632 633 634
    if (kill_list != NULL)
    {
	sfree (kill_list);
	kill_list = NULL;
    }
635 636 637

    if (changed == TRUE)
	dump_connections();
Per Cederqvist's avatar
Per Cederqvist committed
638 639
}

640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678

static char *
get_host_name(IscAddress *addr)
{
    char *res = NULL;
    char *hostname = NULL;
    struct timeval before;
    struct timeval after;
    double diff = -1.0;

    if (param.use_dns)
    {
	if (gettimeofday(&before, NULL) < 0)
	    kom_log("gettimeofday failed: %s\n", strerror(errno));

	res = hostname = isc_gethostname(addr, NULL, 0);

	if (gettimeofday(&after, NULL) < 0)
	    kom_log("gettimeofday failed: %s\n", strerror(errno));

	diff = (after.tv_sec - before.tv_sec
		+ 1e-6 * (after.tv_usec - before.tv_usec));
    }

    if (res == NULL)
	res = isc_getipnum(addr, NULL, 0);

    if (param.use_dns && diff > param.dns_log_threshold)
    {
	if (hostname == NULL)
	    kom_log("Slow bad DNS: %s failed after %f seconds\n", res, diff);
	else
	    kom_log("Slow DNS: got %s after %f seconds\n", res, diff);
    }

    return res;
}


Per Cederqvist's avatar
Per Cederqvist committed
679
static void
Per Cederqvist's avatar
Per Cederqvist committed
680
login_request(IscEvent  *event)
Per Cederqvist's avatar
Per Cederqvist committed
681 682
{
    Connection  * cp;
683
    const char *realuser;
684
    char *hostname = NULL;
685
    char peername[256];
686 687 688
    char portbuf[1+2+3*sizeof(long)];
    size_t hostlen;
    size_t portlen;
Per Cederqvist's avatar
Per Cederqvist committed
689 690

    /* Supress logins if /etc/nologin exists */
David Byers's avatar
David Byers committed
691
    if (fexists(param.nologin_file))
Per Cederqvist's avatar
Per Cederqvist committed
692
    {
693
	isc_puts("%% No logins allowed.\n", event->session);
Per Cederqvist's avatar
Per Cederqvist committed
694
	isc_flush(event->session);
Per Cederqvist's avatar
Per Cederqvist committed
695
 	isc_destroy(kom_server_mcb, event->session);
Per Cederqvist's avatar
Per Cederqvist committed
696 697 698
	return;
    }

699
    hostname = get_host_name(event->session->info.tcp.raddr);
700
    if (hostname == NULL)
David Byers's avatar
David Byers committed
701
	kom_log("WNG: login_request(): unknown hostid.\n");
702

703 704 705
    /* Get the real user name, as returned by the Ident protocol (rfc 931). */
    realuser = get_real_username(event->session, hostname);
    if (realuser == NULL && param.authentication_level == 2)
Per Cederqvist's avatar
Per Cederqvist committed
706
    {
David Byers's avatar
David Byers committed
707
	kom_log("Connection from %s rejected - no IDENT available.\n", 
708
	     hostname);
Per Cederqvist's avatar
Per Cederqvist committed
709

710 711 712 713 714
	isc_puts("%% No IDENT server reachable at your site.\n",
		 event->session);
	isc_flush(event->session);
	isc_destroy(kom_server_mcb, event->session);
	return;
Per Cederqvist's avatar
Per Cederqvist committed
715
    }
716

717 718
    /* Create a Connection, and link the Connection and the
       isc_session together. */
719

720 721 722
    cp = new_client();
    cp->isc_session = event->session;
    event->session->udg = cp;
723

724 725
    if (hostname == NULL)
	s_crea_str(&cp->hostname, "unknown");
726
    else
727 728 729 730 731 732
	s_crea_str(&cp->hostname, hostname);

    if (realuser != NULL)
	s_crea_str(&cp->ident_user, realuser);

    BUG(("\n[Client %lu from %s is connecting]\n", cp->session_no, hostname));
733 734


735 736 737
    isc_getipnum(event->session->info.tcp.raddr, peername, sizeof(peername));
    hostlen = strlen(peername);
    if (hostlen >= sizeof(peername)-1)
738 739 740 741
    {
	kom_log("login_request(): truncated remote peer address %s.\n",
		peername);
    }
742 743 744
    sprintf(portbuf, " %d", isc_getportnum(event->session->info.tcp.raddr));
    portlen = strlen(portbuf);
    cp->peer = smalloc(hostlen + portlen + 1);
745
    strcpy(cp->peer, peername);
746
    strcpy(cp->peer + hostlen, portbuf);
747 748

    dump_connections();
Per Cederqvist's avatar
Per Cederqvist committed
749 750 751
}

static void
Per Cederqvist's avatar
Per Cederqvist committed
752
logout_request(IscEvent *event)
Per Cederqvist's avatar
Per Cederqvist committed
753 754 755
{
    Connection  * cp;
    
756
    cp = event->session->udg;
Per Cederqvist's avatar
Per Cederqvist committed
757
	      
758
    BUG(("\n[Client %lu from %s", cp->session_no,
759
	 get_host_name(event->session->info.tcp.raddr)));
760 761 762
    BUG((" is logging out]\n"));

    add_to_kill_list(cp);
Per Cederqvist's avatar
Per Cederqvist committed
763 764 765 766
}


static void
Per Cederqvist's avatar
Per Cederqvist committed
767
message_request(IscEvent *event)
Per Cederqvist's avatar
Per Cederqvist committed
768 769 770 771
{
    Connection *cp;
    String      tmp_str;

772 773 774 775 776 777 778
    cp = event->session->udg;
    VBUG(("\n[Message from client %lu]\n", cp->session_no));

    /* Pass the message on to the parser */
    tmp_str.string = (unsigned char *)event->msg->buffer;
    tmp_str.len    = event->msg->length;
    parse_message(cp, tmp_str);
Per Cederqvist's avatar
Per Cederqvist committed
779 780 781 782 783
}

void
toploop(void)
{
David Byers's avatar
David Byers committed
784
    time_t      last_time;
785
    IscEvent  * event;
Per Cederqvist's avatar
Per Cederqvist committed
786 787 788 789
    Bool	pending_input = TRUE; /* Should be TRUE whenever there
				         is or might be pending input
					 from any client in the unparsed
					 buffer. */
790 791 792
    long	timeout = 0;        /* In milliseconds. Start with a
				       small value since we should
				       start garbing right away. */
Per Cederqvist's avatar
Per Cederqvist committed
793 794
    while ( !go_and_die )
    {
795
        if (do_statistics)
Per Cederqvist's avatar
Per Cederqvist committed
796 797
	{
	    dump_statistics();
798
	    do_statistics = 0;
Per Cederqvist's avatar
Per Cederqvist committed
799 800
	}

801 802 803 804 805
        if (reread_param)
        {
            free_aux_item_definitions();
            initialize_aux_items(param.aux_def_file);
            reread_param = FALSE;
806
            kom_log("Signal WINCH received. aux definitions reloaded.\n");
807 808
        }

809
	intr_syscalls_on_intr();
Per Cederqvist's avatar
Per Cederqvist committed
810 811
	event = isc_getnextevent(kom_server_mcb,
				 pending_input ? 0 : timeout );
812
	restart_syscalls_on_intr();
Per Cederqvist's avatar
Per Cederqvist committed
813

David Byers's avatar
David Byers committed
814
        last_time = current_time;
Per Cederqvist's avatar
Per Cederqvist committed
815
	current_time = time(NULL);
David Byers's avatar
David Byers committed
816 817
        if (current_time < last_time)
        {
818
            kom_log("WARNING: Time is moving in the wrong direction\n");
819
            /* FIXME (bug 62): Should we take more decisive action here? */
David Byers's avatar
David Byers committed
820 821
        }

Per Cederqvist's avatar
Per Cederqvist committed
822
	timeout = 0;
Per Cederqvist's avatar
Per Cederqvist committed
823 824 825 826

	if ( event == NULL )
	    restart_kom("toploop(): Got NULL event - shouldn't happen...\n");

827
#ifndef USING_RLIMIT_NOFILE
828 829 830
	if (event->event == ISC_EVENT_LOGIN
	    && event->session->fd >= fd_ceiling)
	{
831
	    event->event = ISC_EVENT_LOGIN_UNRELOCATED;
832
	}
833 834
#endif

Per Cederqvist's avatar
Per Cederqvist committed
835 836 837 838 839
	switch ( event->event )
	{
	case ISC_EVENT_ERROR:
	    if (errno != EINTR)
	    {
David Byers's avatar
David Byers committed
840
		kom_log("toploop: ISC_EVENT_ERROR (error = '%s'):\n   '%s'\n",
Per Cederqvist's avatar
Per Cederqvist committed
841 842 843 844 845 846 847
		    strerror(errno), event->msg ? event->msg->buffer
		    : "(unknown)");
	    }
	    break;
	    
	case ISC_EVENT_TIMEOUT:
	    BUG((">"));
848
#ifndef NDEBUG
849 850
	    if (buglevel > 0)
		fflush(stdout);
Per Cederqvist's avatar
Per Cederqvist committed
851 852 853 854
#endif
	    if ( pending_input == FALSE )
		timeout = end_of_atomic(TRUE); /* Idle. Do some cleaning up. */
	    else
855
		pending_input = (parse_forgotten() ? FALSE : TRUE);
Per Cederqvist's avatar
Per Cederqvist committed
856 857 858 859 860 861 862 863
	    	    
	    break;
	    
	case ISC_EVENT_LOGIN:
	    pending_input = TRUE;
	    login_request(event);
	    break;

864 865 866
	case ISC_EVENT_LOGIN_UNRELOCATED:
	    pending_input = TRUE;
	    BUG(("Connection attempt rejected.\n"));
867
	    isc_puts("%% No connections left.\n", event->session);
868 869 870 871 872 873
	    isc_flush(event->session);
	    isc_destroy(kom_server_mcb, event->session);

	    async_rejected_connection();
	    break;

Per Cederqvist's avatar
Per Cederqvist committed
874 875 876 877 878 879 880 881 882 883 884 885
	case ISC_EVENT_LOGOUT:
	    pending_input = TRUE;
	    logout_request(event);
	    break;

 	case ISC_EVENT_MESSAGE:
	    pending_input = TRUE;
	    message_request(event);
	    break;

	default:
	    pending_input = TRUE;
David Byers's avatar
David Byers committed
886
	    kom_log("ERROR: toploop(): Unknown ISC_EVENT\n");
Per Cederqvist's avatar
Per Cederqvist committed
887 888 889 890 891 892 893 894
	    break;
	}

        isc_dispose(event);

	check_kill_flg();
    }
}