connections.c 29.3 KB
Newer Older
Linus Tolke Y's avatar
Linus Tolke Y committed
1
/*
2
 * $Id: connections.c,v 0.125 2003/08/20 17:40:36 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
 *
 * 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.
 *
Per Cederqvist's avatar
Per Cederqvist committed
23
 * Please report bugs at http://bugzilla.lysator.liu.se/. 
Linus Tolke Y's avatar
Linus Tolke Y committed
24
 */
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>
46
#include "timewrap.h"
47
#include <sys/socket.h>
48
#include <signal.h>
49
#include <assert.h>
50
#include <netdb.h>
Per Cederqvist's avatar
Per Cederqvist committed
51
#include <stdlib.h>
Per Cederqvist's avatar
Per Cederqvist committed
52

53
#include "adns.h"
54 55 56
#include "oop.h"

#include "unused.h"
57
#include "ldifftime.h"
Per Cederqvist's avatar
Per Cederqvist committed
58
#include "misc-types.h"
59
#include "s-string.h"
Per Cederqvist's avatar
Per Cederqvist committed
60
#include "kom-types.h"
61
#include "kom-memory.h"
Per Cederqvist's avatar
Per Cederqvist committed
62
#include "debug.h"
63
#include "isc-interface.h"
Per Cederqvist's avatar
Per Cederqvist committed
64
#include "com.h"
65
#include "async.h"
Per Cederqvist's avatar
Per Cederqvist committed
66
#include "connections.h"
Per Cederqvist's avatar
Per Cederqvist committed
67
#include "internal-connections.h"
Per Cederqvist's avatar
Per Cederqvist committed
68
#include "prot-a-parse-arg.h"
Per Cederqvist's avatar
Per Cederqvist committed
69 70 71 72 73
#include "log.h"
#include "lyskomd.h"
#include "services.h"
#include "isc-parse.h"
#include "prot-a.h"
74
#include "prot-a-parse.h"
Per Cederqvist's avatar
Per Cederqvist committed
75 76 77 78
#include "server/smalloc.h"
#include "end-of-atomic.h"
#include "send-async.h"
#include "cache.h"
79
#include "rfc931.h"
80
#include "param.h"
David Byers's avatar
David Byers committed
81
#include "kom-config.h"
82
#include "kom-errno.h"
Per Cederqvist's avatar
Per Cederqvist committed
83
#include "sigflags.h"
Per Cederqvist's avatar
Per Cederqvist committed
84
#include "server-time.h"
85
#include "aux-items.h"
86
#include "eintr.h"
87
#include "text-garb.h"
88
#include "timeval-util.h"
89
#include "stats.h"
90
#include "string-malloc.h"
91
#include "manipulate.h"
Per Cederqvist's avatar
Per Cederqvist committed
92

93 94
oop_source_sys * kom_server_oop_src = NULL;
struct isc_mcb * kom_server_mcb    = NULL;
Per Cederqvist's avatar
Per Cederqvist committed
95 96
Connection     * active_connection = NULL;

Per Cederqvist's avatar
Per Cederqvist committed
97 98 99
/*
 * 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
100
 * privileges issues a `shutdown', or of lyskomd receives a SIGTERM.
Per Cederqvist's avatar
Per Cederqvist committed
101 102
 * This not an abort: all data is saved before we exit.
 */
103
Bool go_and_die = FALSE;
Per Cederqvist's avatar
Per Cederqvist committed
104 105

/*
106 107 108 109 110 111 112 113 114
 * The number of times that the session penalties has been averaged.
 * Beware: this number will wrap around.
 */
static unsigned int penalty_generation = 0;

/*
 * These state variables are used to find out if we are busy or not.
 * When a packet arrives, data_available_callback() will set work_done
 * to TRUE and is_idle to FALSE.
Per Cederqvist's avatar
Per Cederqvist committed
115
 */
116 117
static Bool work_done = FALSE;
static Bool is_idle = FALSE;
Per Cederqvist's avatar
Per Cederqvist committed
118 119 120 121 122 123 124 125

jmp_buf 	 parse_env;


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

126
const int num_fnc_defs = sizeof (fnc_defs) / sizeof (Fnc_descriptor);
127

Per Cederqvist's avatar
Per Cederqvist committed
128
unsigned long service_statistics[sizeof (fnc_defs) / sizeof (Fnc_descriptor)];
Per Cederqvist's avatar
Per Cederqvist committed
129 130 131

BUGDECL;

132 133 134
static oop_call_fd data_available_callback;
static oop_call_time check_kill_flg;
static oop_call_time check_idle_callback;
135 136 137
static isc_write_error_cb write_err_cb;
static isc_stale_output_cb stale_cb;
static isc_stale_output_cb idle_cb;
138 139 140 141

static Connection *queue_first = NULL;
static Connection *queue_last = NULL;

142 143 144
static void busy(void);


145 146 147 148 149 150 151 152 153 154 155 156 157 158 159
static void
queue_add(Connection *c)
{
    assert(c->on_queue == FALSE);
    c->on_queue = TRUE;

    c->queue_prev = queue_last;
    c->queue_next = NULL;

    if (queue_first == NULL)
	queue_first = c;
    else
	queue_last->queue_next = c;

    queue_last = c;
160
    update_stat(STAT_RUN_QUEUE, 1);
161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176
}

static void
queue_remove(Connection *c)
{
    assert(c->on_queue == TRUE);
    c->on_queue = FALSE;

    if (c->queue_next != NULL)
	c->queue_next->queue_prev = c->queue_prev;
    else
	queue_last = c->queue_prev;
    
    if (c->queue_prev != NULL)
	c->queue_prev->queue_next = c->queue_next;
    else
177
	queue_first = c->queue_next;
Per Cederqvist's avatar
Per Cederqvist committed
178

179 180
    c->queue_prev = NULL;
    c->queue_next = NULL;
181
    update_stat(STAT_RUN_QUEUE, -1);
182 183
}

Per Cederqvist's avatar
Per Cederqvist committed
184
void
185 186
set_time(void)
{
187 188
    struct timeval last_time;
    static int limiter = 0;
189 190

    last_time = current_time;
191 192 193 194 195 196 197 198 199 200 201
    if (gettimeofday(&current_time, NULL) < 0)
    {
	if (limiter < 50)
	{
	    kom_log("WARNING: gettimeofday failed: %s\n", strerror(errno));
	    if (++limiter == 50)
		kom_log("WARNING: will not log the above message again.\n");
	}
    }

    if (timeval_less(current_time, last_time))
202
    {
203 204
	kom_log("WARNING: Time moved backward at least %g seconds.",
		timeval_diff_d(last_time, current_time));
205 206 207
	/* FIXME (bug 62): Should we take more decisive action here? */
    }
}
Per Cederqvist's avatar
Per Cederqvist committed
208

Per Cederqvist's avatar
Per Cederqvist committed
209
static void
Per Cederqvist's avatar
Per Cederqvist committed
210 211 212
logout_client(Connection *cp)
{
    Connection *real_active_connection;
213
    int ret;
Per Cederqvist's avatar
Per Cederqvist committed
214 215 216

    if ( active_connection != NULL )
    {
David Byers's avatar
David Byers committed
217
	kom_log("BUGCHK: logout_client(%ld): connection %ld is active.\n",
Per Cederqvist's avatar
Per Cederqvist committed
218 219 220 221 222
	    cp->session_no, active_connection->session_no);
    }
    
    if ( cp->pers_no != 0 )
    {
223 224 225 226 227 228 229 230 231 232 233 234
	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
235 236 237 238
	active_connection = cp;
	logout();
	active_connection = real_active_connection;
    }
239 240
    else
    {
241
#if 0
242
	/* FIXME (bug 908): send a new async here instead.  This causes the
243 244
	   elisp client to say that a secret (or unknown) person has
	   left the system.  */
245
        async_logout( 0, cp->session_no );
246
#endif
247
    }
Per Cederqvist's avatar
Per Cederqvist committed
248 249 250 251 252 253 254 255 256 257 258 259 260 261

    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");
    }

262 263
    ret = isc_destroy(kom_server_mcb, cp->isc_session);
    if (ret < 0)
David Byers's avatar
David Byers committed
264
	kom_log("logout_client(): isc_destroyed returned %d\n", ret);
265
    cp->isc_session = NULL;
266 267
    if (cp->on_queue)
	queue_remove(cp);
Per Cederqvist's avatar
Per Cederqvist committed
268 269

    kill_client(cp);		/* Free the Connection */
270
    update_stat(STAT_CLIENTS, -1);
Per Cederqvist's avatar
Per Cederqvist committed
271 272
}

Per Cederqvist's avatar
Per Cederqvist committed
273 274 275 276 277 278 279 280 281 282 283 284 285 286
/*
 * 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 )
287
	    restart_kom("logout_all_clients(): cant get session %ld.\n",
Per Cederqvist's avatar
Per Cederqvist committed
288 289 290 291 292 293
			sess);
	else
	    logout_client (conn);
    }

    if ( traverse_connections (0) != 0)
294
	restart_kom("logout_all_clients(): traverse_connections(0) == %ld.\n",
Per Cederqvist's avatar
Per Cederqvist committed
295 296 297 298
		    traverse_connections(0));
}

    
Per Cederqvist's avatar
Per Cederqvist committed
299 300 301 302 303 304 305 306
    

    
/*
 * 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
307 308
call_function(Connection *client,
	      union result_holder *res)
Per Cederqvist's avatar
Per Cederqvist committed
309 310 311 312 313
{
    Success	status=FAILURE;	/* OK if the call was successful. */

    if ( active_connection != NULL )
    {
314
	kom_log("call_function(%ld): active_connection = %ld\n",
Per Cederqvist's avatar
Per Cederqvist committed
315 316
	    client->session_no, active_connection->session_no);
    }
317 318 319

    if (client->function == illegal_fnc) 
    {
320
        err_stat = 0;
321 322 323 324
	kom_errno = KOM_NOT_IMPL;
	return FAILURE;
    }

Per Cederqvist's avatar
Per Cederqvist committed
325 326
    active_connection = client;

327
    service_statistics[client->function_index]++;
Per Cederqvist's avatar
Per Cederqvist committed
328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350

#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';
351 352
	    isc_puts("%%LysKOM unsupported protocol.\n", client->isc_session);
	    isc_flush(client->isc_session);
Per Cederqvist's avatar
Per Cederqvist committed
353
	    BUG(("%%%%Unsupported protocol.\n"));
354
	    longjmp(parse_env, KOM_LOGOUT);
Per Cederqvist's avatar
Per Cederqvist committed
355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383
	}
    }

    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
384 385 386
    sfree(client->misc_info_list.misc);
    client->misc_info_list.misc = 0;
    client->misc_info_list.no_of_misc = 0;
387
    s_clear(&client->aux_item.data);
388
    s_clear(&client->dummy_aux_item.data);
389 390 391
    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
392 393
    client->parse_pos = 0;
    client->fnc_parse_pos = 0;
394
    client->array_parse_index = 0;
David Byers's avatar
David Byers committed
395
    client->array_parse_parsed_length = 0;
Per Cederqvist's avatar
Per Cederqvist committed
396 397 398
    client->array_parse_pos = 0;
    client->struct_parse_pos = 0;
    client->string_parse_pos = 0;
David Byers's avatar
David Byers committed
399 400 401
    client->hunt_parse_pos = 0;
    client->array_hunt_num = 0;
    client->array_hunt_depth = 0;
402 403 404
    sfree(client->num_list.data);
    client->num_list.data = NULL;
    client->num_list.length = 0;
405 406
    free_aux_item_list(&client->aux_item_list);
    client->info.highest_aux_no = 0;
Per Cederqvist's avatar
Per Cederqvist committed
407 408 409 410 411 412 413
}

/*
 * Send a reply to a call.
 */
static void
reply(Connection *client,
414 415
      Success status,
      union result_holder *result)
Per Cederqvist's avatar
Per Cederqvist committed
416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431
{
    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.
432 433
 * If more data is needed set client->more_to_parse to FALSE.  Returns
 * TRUE if anything was (or might have been) written to the client.
Per Cederqvist's avatar
Per Cederqvist committed
434
 */
435
static Bool
Per Cederqvist's avatar
Per Cederqvist committed
436 437 438
parse_unparsed(Connection *client)
{
    Success       status;
439
    union result_holder result;
Per Cederqvist's avatar
Per Cederqvist committed
440 441 442 443 444 445
        
    switch ( setjmp(parse_env) )
    {
    case 0 :
	/* Parse message. If message is complete call function and reply. */
	parse_packet(client);
446 447
	if (client->blocked_by_dns)
	    return TRUE;
448
	update_stat(STAT_REQUESTS, 1);
Per Cederqvist's avatar
Per Cederqvist committed
449
	status = call_function(client, &result);
450
	update_stat(STAT_REQUESTS, -1);
Per Cederqvist's avatar
Per Cederqvist committed
451
	reply(client, status, &result);
452
	client->penalty += param.penalty_per_call;
Per Cederqvist's avatar
Per Cederqvist committed
453
	free_parsed(client);
454
	end_of_atomic();
455
	return TRUE;
Per Cederqvist's avatar
Per Cederqvist committed
456

457
    case KOM_PROTOCOL_ERR:
Per Cederqvist's avatar
Per Cederqvist committed
458 459
	s_clear(&client->string0);
	free_parsed(client);
460
	isc_puts("%% LysKOM protocol error.\n", client->isc_session);
Per Cederqvist's avatar
Per Cederqvist committed
461
	BUG(("%%%% Protocol error.\n"));
462
	client->penalty += param.max_penalty;
Per Cederqvist's avatar
Per Cederqvist committed
463 464 465
	s_clear(&client->unparsed);
	client->first_to_parse = 0;
	client->more_to_parse = FALSE;
466
	end_of_atomic();
467
	return TRUE;
Per Cederqvist's avatar
Per Cederqvist committed
468

469
    case KOM_MSG_INCOMPLETE:
Per Cederqvist's avatar
Per Cederqvist committed
470
	client->more_to_parse = FALSE;
471
	return FALSE;
Per Cederqvist's avatar
Per Cederqvist committed
472

473
    case KOM_LOGOUT:
474
	add_to_kill_list(client);
475
	client->more_to_parse = FALSE;
476 477 478
	return TRUE;
    default:
	restart_kom("Bad longjmp return value.\n");
Per Cederqvist's avatar
Per Cederqvist committed
479
    }
480
    /*NOTREACHED*/
Per Cederqvist's avatar
Per Cederqvist committed
481 482 483 484 485
}


/* Return 1 if the named file exists, 0 otherwise */
static int
Per Cederqvist's avatar
Per Cederqvist committed
486
fexists(const char *filename)
Per Cederqvist's avatar
Per Cederqvist committed
487 488 489 490 491 492 493 494 495 496 497 498 499 500
{
    struct stat buf;
    int code;
  
    code = !stat(filename, &buf);
    errno = 0;

    return code;
}


void
dump_statistics(void)
{
501
    static struct timeval last_dump = {0, 0};
Per Cederqvist's avatar
Per Cederqvist committed
502 503 504
    int i;
    FILE *fp;

505
    if ((fp = i_fopen(param.statistic_name, "a")) == NULL)
Per Cederqvist's avatar
Per Cederqvist committed
506
    {
507 508
	kom_log("dump_statistics(): can't open file %s\n",
		param.statistic_name);
Per Cederqvist's avatar
Per Cederqvist committed
509 510 511
	return;
    }

512
    if (timeval_zero(last_dump))
Per Cederqvist's avatar
Per Cederqvist committed
513 514
    {
	fprintf(fp, "RESTART\n");
Per Cederqvist's avatar
Per Cederqvist committed
515
	last_dump = current_time;
Per Cederqvist's avatar
Per Cederqvist committed
516 517
    }
    
518 519
    fprintf(fp, "TIME: %s", ctime(&current_time.tv_sec));
    fprintf(fp, "SECONDS: %ld\n", timeval_diff_sec(current_time, last_dump));
Per Cederqvist's avatar
Per Cederqvist committed
520
    fprintf(fp, "STATISTICS:");
521 522 523 524 525

    /* 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
526
    {
527
	fprintf(fp, " %d:%lu", fnc_defs[i].function, service_statistics[i]);
Per Cederqvist's avatar
Per Cederqvist committed
528 529 530 531
	service_statistics[i]=0;
    }

    fprintf(fp, "\n");
532
    i_fclose(fp);
Per Cederqvist's avatar
Per Cederqvist committed
533

Per Cederqvist's avatar
Per Cederqvist committed
534
    last_dump = current_time;
Per Cederqvist's avatar
Per Cederqvist committed
535 536
}

537 538
/* List of connections to kill. */

Per Cederqvist's avatar
Per Cederqvist committed
539 540
static Session_no *kill_list = NULL;
static int kill_list_size = 0;
541
static int kill_pending = 0;
542 543 544 545 546

/* Schedule this client for termination. */
void
add_to_kill_list(Connection *conn)
{
547
    oop_source *source;
Per Cederqvist's avatar
Per Cederqvist committed
548 549
    int i;

550 551 552 553 554 555 556 557
    if (conn->kill_pending)
    {
	for (i = 0; i < kill_list_size; i++)
	    if (kill_list[i] == conn->session_no)
		return;
	restart_kom("add_to_kill_list(): kill_pending set but not on list.\n");
    }

Per Cederqvist's avatar
Per Cederqvist committed
558
    for (i = 0; i < kill_list_size; i++)
559
	if (kill_list[i] == conn->session_no)
560
	    restart_kom("add_to_kill_list(): on list but not kill_pending.\n");
Per Cederqvist's avatar
Per Cederqvist committed
561

562 563 564 565 566 567 568 569 570 571 572 573 574 575 576
    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;
577
    conn->kill_pending = TRUE;
578 579 580

    if (!kill_pending)
    {
581
	source = isc_getoopsource(conn->isc_session);
582 583 584
	source->on_time(source, OOP_TIME_NOW, check_kill_flg, NULL);
	kill_pending = 1;
    }
585
}
Per Cederqvist's avatar
Per Cederqvist committed
586

587 588 589 590 591 592 593 594

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

595
    if ((fp = i_fopen(param.connection_status_file_tmp, "w")) == NULL)
596
    {
597 598
	kom_log("dump_connections(): can't open file %s: %s\n",
		param.connection_status_file_tmp, strerror(errno));
599 600 601 602 603 604
	return;
    }

    for (s = 0; (s = traverse_connections(s)) != 0;)
    {
	conn = get_conn_by_number(s);
605 606
	fprintf(fp, "%d %lu %d %s\n", conn->isc_session->fd, conn->session_no,
		handshake_ok(conn, 0),
607 608 609
		conn->peer);
    }

610 611 612 613 614 615
    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");

616
    if (i_fclose(fp) < 0)
617 618 619 620 621
    {
	kom_log("dump_connections(): fclose failed: %s (ignored)\n",
		strerror(errno));
    }

622
    errno = 0;
623 624
    if (i_rename(param.connection_status_file_tmp,
		 param.connection_status_file) < 0)
625
    {
626
	kom_log("dump_connections(): can't rename %s to %s: %s\n",
627
		param.connection_status_file_tmp,
628 629
		param.connection_status_file,
		strerror(errno));
630 631 632 633
    }
}


Per Cederqvist's avatar
Per Cederqvist committed
634 635 636
/*
 * check_kill_flg must NEVER be called inside an atomic call!
 */
637 638 639 640
static void *
check_kill_flg(oop_source *UNUSED(source),
	       struct timeval UNUSED(tv),
	       void *UNUSED(user))
Per Cederqvist's avatar
Per Cederqvist committed
641 642
{
    Connection *conn;
643
    Bool changed = FALSE;
Per Cederqvist's avatar
Per Cederqvist committed
644

645 646
    kill_pending = 0;

Per Cederqvist's avatar
Per Cederqvist committed
647 648
    if ( active_connection != NULL )
    {
649
	restart_kom("check_kill_flg: active_connection == %ld",
Per Cederqvist's avatar
Per Cederqvist committed
650 651 652
		    active_connection->session_no);
    }

653
    while (kill_list_size > 0)
Per Cederqvist's avatar
Per Cederqvist committed
654
    {
655 656 657
	--kill_list_size;
	conn = get_conn_by_number (kill_list[kill_list_size]);
	if (conn == NULL)
Per Cederqvist's avatar
Per Cederqvist committed
658
	{
David Byers's avatar
David Byers committed
659
	    kom_log("check_kill_flg(): Connection %ld doesn't exist.\n",
660 661 662 663
		kill_list[kill_list_size]);
	}
	else
	{
664 665
	    assert(conn->kill_pending);
	    conn->kill_pending = FALSE;
666 667
	    logout_client(conn);
	    end_of_atomic();
668
	    changed = TRUE;
Per Cederqvist's avatar
Per Cederqvist committed
669 670
	}
    }
671

672 673 674 675 676
    if (kill_list != NULL)
    {
	sfree (kill_list);
	kill_list = NULL;
    }
677 678 679

    if (changed == TRUE)
	dump_connections();
680 681

    return OOP_CONTINUE;
Per Cederqvist's avatar
Per Cederqvist committed
682 683
}

684 685 686 687
static void *
dns_resolution(struct isc_scb *scb,
	       enum isc_resolve_status res,
	       long errcode)
688 689 690
{
    struct timeval after;
    double diff = -1.0;
691 692
    Connection *conn;
    char *hostname = NULL;
693

694
    update_stat(STAT_DNS_QUEUE, -1);
695

696
    conn = scb->udg;
697

698 699 700 701
    conn->dns_done = TRUE;
    if (conn->blocked_by_dns)
    {
	conn->blocked_by_dns = FALSE;
702 703
	if (!conn->on_queue)
	    queue_add(conn);
704 705
    }

706 707 708 709 710 711 712
    if (res == isc_resolve_aborted)
	return OOP_CONTINUE;

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

    diff = timeval_diff_d(after, conn->connect_time);
713

714 715 716
    busy();

    switch (res)
717
    {
718
    case isc_resolve_h_errno:
719
	if (hostname == NULL)
720 721 722 723 724 725 726 727 728 729
	    hostname = s_crea_c_str(scb->remote);

	if (errcode == HOST_NOT_FOUND)
	    kom_log("No hostname found for %s.\n", hostname);
	else if (errcode == TRY_AGAIN)
	    kom_log("Lookup of %s timed out.\n", hostname);
	else if (errcode == NO_RECOVERY)
	    kom_log("Non-recoverable error looking up %s.\n", hostname);
	else if (errcode == NO_ADDRESS)
	    kom_log("Got NO_ADDRESS error looking up %s.\n", hostname);
730
	else
731 732
	    kom_log("Unknown resolver error %ld looking up %s.\n",
		    errcode, hostname);
733
	break;
734

735
    case isc_resolve_adns_error:
736 737 738
	if (hostname == NULL)
	    hostname = s_crea_c_str(scb->remote);

739 740 741 742 743 744
	/* Misconfigurations of localhost are common and harmless.
	   Don't bother logging them, since that makes the test cases fail. */
	if ((errcode != adns_s_inconsistent && errcode != adns_s_nxdomain)
	    || strcmp(hostname, "127.0.0.1") != 0)
	    kom_log("Error looking up %s: %s\n",
		    hostname, adns_strerror(errcode));
745 746 747 748 749 750 751
	break;

    case isc_resolve_aborted:
	abort();

    case isc_resolve_ok:
	break;
752 753
    }

754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769
    if (diff > param.dns_log_threshold)
    {
	if (hostname == NULL)
	    hostname = s_crea_c_str(scb->remote);

	if (res == isc_resolve_ok)
	    kom_log("Slow DNS: got %s after %f seconds\n", hostname, diff);
	else
	    kom_log("Slow bad DNS: %s failed after %f seconds\n",
		    hostname, diff);
   }

    if (hostname != NULL)
	string_free(hostname); 

    return OOP_CONTINUE;
770 771
}

772
    
773
static void
774 775
write_err_cb(struct isc_scb *cb_session,
	     int saved_errno)
776
{
777
    Connection  * cp = cb_session->udg;
778
    if (saved_errno != ECONNRESET && saved_errno != EPIPE)
779 780
	kom_log("Failed to write to client %lu from %s: %s\n",
		cp->session_no, cp->peer, strerror(saved_errno));
781
    cp->penalty += param.max_penalty;
782 783 784 785
    add_to_kill_list(cp);
}


786
static void
787
stale_cb(struct isc_scb *cb_session)
788
{
789
    Connection *cp = cb_session->udg;
790 791 792 793 794 795
    kom_log("Client %lu from %s has stalled.  Killing it.\n",
	    cp->session_no, cp->peer);
    cp->penalty += param.max_penalty;
    add_to_kill_list(cp);
}
    
796

797
static void
798
idle_cb(struct isc_scb *cb_session)
799
{
800
    Connection *cp = cb_session->udg;
801 802 803 804 805 806 807
    kom_log("Client %lu from %s has been idle too long.  Killing it.\n",
	    cp->session_no, cp->peer);
    cp->penalty += param.max_penalty;
    add_to_kill_list(cp);
}


Per Cederqvist's avatar
Per Cederqvist committed
808
static void
809
login_request(struct isc_scb *session)
Per Cederqvist's avatar
Per Cederqvist committed
810 811
{
    Connection  * cp;
812
    const char *realuser;
813 814
    char portbuf[1+2+3*sizeof(long)];
    size_t portlen;
815
    char *remote_ip = NULL;
Per Cederqvist's avatar
Per Cederqvist committed
816 817

    /* Supress logins if /etc/nologin exists */
David Byers's avatar
David Byers committed
818
    if (fexists(param.nologin_file))
Per Cederqvist's avatar
Per Cederqvist committed
819
    {
820 821 822
	isc_puts("%% No logins allowed.\n", session);
	isc_flush(session);
 	isc_destroy(kom_server_mcb, session);
Per Cederqvist's avatar
Per Cederqvist committed
823 824 825
	return;
    }

826 827
    /* Create a Connection, and link the Connection and the
       isc_session together. */
828

829
    cp = new_client();
830 831
    cp->isc_session = session;
    session->udg = cp;
832
    update_stat(STAT_CLIENTS, 1);
833

834 835 836
    /* Store the IP address in readable form. */
    s_crea_str(&cp->remote_ip, isc_getipnum(session->raddr, NULL, 0));
    remote_ip = s_crea_c_str(cp->remote_ip);
837

838
    /* Initiate DNS lookup. */
839
    if (param.use_dns && isc_resolve_remote(session, dns_resolution) == 0)
840
	update_stat(STAT_DNS_QUEUE, 1);
841
    else
842
	s_strcpy(&session->remote, cp->remote_ip);
843

844 845 846 847 848 849
    /* Update the status file that contains all connection. */
    sprintf(portbuf, " %d", isc_getportnum(session->raddr));
    portlen = strlen(portbuf);
    cp->peer = smalloc(s_strlen(cp->remote_ip) + portlen + 1);
    strcpy(cp->peer, remote_ip);
    strcpy(cp->peer + s_strlen(cp->remote_ip), portbuf);
850

851
    dump_connections();
852

853 854 855 856
    /* Start with max penalty, so that it doesn't pay to make a lot of
       new connections.  */
    cp->penalty = param.max_penalty;
    cp->penalty_generation = penalty_generation;
857

858 859 860
    cp->schedule.priority = param.default_priority;
    cp->schedule.weight = param.default_weight;

861 862 863
    /* Get the real user name, as returned by the Ident protocol (rfc 931). */
    realuser = get_real_username(session, remote_ip);
    if (realuser == NULL && param.authentication_level == 2)
864
    {
865 866 867 868 869 870 871 872 873
	kom_log("Connection from %s rejected - no IDENT available.\n", 
		remote_ip);

	isc_puts("%% No IDENT server reachable at your site.\n",
		 session);
	isc_flush(session);
	logout_client(cp);
	string_free(remote_ip);
	return;
874 875
    }

876 877 878 879
    if (realuser != NULL)
	s_crea_str(&cp->ident_user, realuser);

    BUG(("\n[Client %lu from %s is connecting]\n", cp->session_no, remote_ip));
880

881
    isc_set_read_callback(session, data_available_callback, write_err_cb,
882
			  stale_cb, idle_cb);
883
    string_free(remote_ip);
Per Cederqvist's avatar
Per Cederqvist committed
884 885 886
}

static void
887
adjust_penalty(Connection *conn)
Per Cederqvist's avatar
Per Cederqvist committed
888
{
889 890
    unsigned int gens = penalty_generation - conn->penalty_generation;
    if (gens > 0)
891
    {
892 893 894 895 896 897
	/* The weight is in the range 1-0xffff (inclusive).
	   The penalty is in the range 0-0x10000 (inclusive).
	   This means that the multiplication can never overflow. */

	if (conn->penalty <= gens)
	    conn->penalty = 0;
898
	else
899 900 901 902 903 904 905 906 907
	{
	    unsigned int tmp = conn->penalty - gens * conn->schedule.weight;
	    if (tmp < conn->penalty)
		conn->penalty = tmp;
	    else
		conn->penalty = 0;
	}

	conn->penalty_generation = penalty_generation;
908
    }
Per Cederqvist's avatar
Per Cederqvist committed
909 910 911 912
}


static void
913
read_from_connection(Connection *conn)
Per Cederqvist's avatar
Per Cederqvist committed
914
{
915
    Bool would_block = FALSE;
916
    Bool need_flush = FALSE;
917
    String_size pre;
Per Cederqvist's avatar
Per Cederqvist committed
918

919 920
    adjust_penalty(conn);

921
    while (!would_block && !go_and_die && conn->penalty < param.max_penalty
922
	   && !conn->kill_pending && !conn->blocked_by_dns)
923
    {
924
	pre = s_strlen(conn->unparsed) - conn->first_to_parse;
925
	while (conn->more_to_parse
926
	       && !go_and_die && conn->penalty < param.max_penalty
927
	       && !conn->kill_pending && !conn->blocked_by_dns)
928
	    need_flush |= parse_unparsed(conn);
929 930
	update_stat(STAT_RECV_QUEUE,
		    s_strlen(conn->unparsed) - conn