worker.c 53.7 KB
Newer Older
1
/*  Copyright (C) 2014-2017 CZ.NIC, z.s.p.o. <knot-dns@labs.nic.cz>
Marek Vavruša's avatar
Marek Vavruša committed
2 3 4 5 6 7 8 9 10 11 12 13

    This program 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 3 of the License, or
    (at your option) any later version.

    This program 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
14
    along with this program.  If not, see <https://www.gnu.org/licenses/>.
Marek Vavruša's avatar
Marek Vavruša committed
15 16
 */

17
#include <uv.h>
18
#include <lua.h>
19
#include <libknot/packet/pkt.h>
20
#include <libknot/descriptor.h>
21 22
#include <contrib/ucw/lib.h>
#include <contrib/ucw/mempool.h>
23
#include <contrib/wire.h>
Marek Vavruša's avatar
Marek Vavruša committed
24 25 26
#if defined(__GLIBC__) && defined(_GNU_SOURCE)
#include <malloc.h>
#endif
27
#include <assert.h>
28 29
#include <sys/types.h>
#include <unistd.h>
30
#include <gnutls/gnutls.h>
31
#include "lib/utils.h"
32
#include "lib/layer.h"
33
#include "daemon/worker.h"
34
#include "daemon/bindings.h"
35
#include "daemon/engine.h"
36
#include "daemon/io.h"
37
#include "daemon/tls.h"
38
#include "daemon/zimport.h"
39
#include "daemon/session.h"
40

41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56

/* Magic defaults for the worker. */
#ifndef MP_FREELIST_SIZE
# ifdef __clang_analyzer__
#  define MP_FREELIST_SIZE 0
# else
#  define MP_FREELIST_SIZE 64 /**< Maximum length of the worker mempool freelist */
# endif
#endif
#ifndef QUERY_RATE_THRESHOLD
#define QUERY_RATE_THRESHOLD (2 * MP_FREELIST_SIZE) /**< Nr of parallel queries considered as high rate */
#endif
#ifndef MAX_PIPELINED
#define MAX_PIPELINED 100
#endif

57
#define VERBOSE_MSG(qry, ...) QRVERBOSE(qry, "wrkr", __VA_ARGS__)
58

59 60 61 62 63 64 65 66 67 68 69 70 71
/** Client request state. */
struct request_ctx
{
	struct kr_request req;
	struct {
		union inaddr addr;
		union inaddr dst_addr;
		/* uv_handle_t *handle; */

		/** NULL if the request didn't come over network. */
		struct session *session;
	} source;
	struct worker_ctx *worker;
72
	struct qr_task *task;
73 74 75 76 77 78 79 80
};

/** Query resolution task. */
struct qr_task
{
	struct request_ctx *ctx;
	knot_pkt_t *pktbuf;
	qr_tasklist_t waiting;
81
	struct session *pending[MAX_PENDING];
82 83 84 85 86 87 88 89 90
	uint16_t pending_count;
	uint16_t addrlist_count;
	uint16_t addrlist_turn;
	uint16_t timeouts;
	uint16_t iter_count;
	struct sockaddr *addrlist;
	uint32_t refs;
	bool finished : 1;
	bool leading  : 1;
91
	uint64_t creation_time;
92 93
};

94

95 96 97 98
/* Convenience macros */
#define qr_task_ref(task) \
	do { ++(task)->refs; } while(0)
#define qr_task_unref(task) \
99
	do { if (task && --(task)->refs == 0) { qr_task_free(task); } } while (0)
100 101 102 103 104

/** @internal get key for tcp session
 *  @note kr_straddr() return pointer to static string
 */
#define tcpsess_key(addr) kr_straddr(addr)
105 106

/* Forward decls */
107
static void qr_task_free(struct qr_task *task);
108 109 110
static int qr_task_step(struct qr_task *task,
			const struct sockaddr *packet_source,
			knot_pkt_t *packet);
111
static int qr_task_send(struct qr_task *task, struct session *session,
112 113 114 115
			struct sockaddr *addr, knot_pkt_t *pkt);
static int qr_task_finalize(struct qr_task *task, int state);
static void qr_task_complete(struct qr_task *task);
static struct session* worker_find_tcp_connected(struct worker_ctx *worker,
116
						 const struct sockaddr *addr);
117 118 119 120 121 122
static int worker_add_tcp_waiting(struct worker_ctx *worker,
				  const struct sockaddr *addr,
				  struct session *session);
static int worker_del_tcp_waiting(struct worker_ctx *worker,
				  const struct sockaddr *addr);
static struct session* worker_find_tcp_waiting(struct worker_ctx *worker,
123
					       const struct sockaddr *addr);
124
static void on_tcp_connect_timeout(uv_timer_t *timer);
125 126 127 128 129 130 131

/** @internal Get singleton worker. */
static inline struct worker_ctx *get_worker(void)
{
	return uv_default_loop()->data;
}

132 133
/*! @internal Create a UDP/TCP handle for an outgoing AF_INET* connection.
 *  socktype is SOCK_* */
134 135
static uv_handle_t *ioreq_spawn(struct worker_ctx *worker,
				int socktype, sa_family_t family, bool has_tls)
136
{
137 138 139
	bool precond = (socktype == SOCK_DGRAM || socktype == SOCK_STREAM)
			&& (family == AF_INET  || family == AF_INET6);
	if (!precond) {
140 141
		/* assert(false); see #245 */
		kr_log_verbose("[work] ioreq_spawn: pre-condition failed\n");
142 143 144
		return NULL;
	}

145
	/* Create connection for iterative query */
146 147
	uv_handle_t *handle = malloc(socktype == SOCK_DGRAM
					? sizeof(uv_udp_t) : sizeof(uv_tcp_t));
148 149 150
	if (!handle) {
		return NULL;
	}
151
	int ret = io_create(worker->loop, handle, socktype, family, has_tls);
152 153 154 155 156
	if (ret) {
		if (ret == UV_EMFILE) {
			worker->too_many_open = true;
			worker->rconcurrent_highwatermark = worker->stats.rconcurrent;
		}
157
		free(handle);
158 159
		return NULL;
	}
160 161 162 163

	/* Bind to outgoing address, according to IP v4/v6. */
	union inaddr *addr;
	if (family == AF_INET) {
164
		addr = (union inaddr *)&worker->out_addr4;
165
	} else {
166
		addr = (union inaddr *)&worker->out_addr6;
167 168 169 170
	}
	if (addr->ip.sa_family != AF_UNSPEC) {
		assert(addr->ip.sa_family == family);
		if (socktype == SOCK_DGRAM) {
171 172 173 174 175
			uv_udp_t *udp = (uv_udp_t *)handle;
			ret = uv_udp_bind(udp, &addr->ip, 0);
		} else if (socktype == SOCK_STREAM){
			uv_tcp_t *tcp = (uv_tcp_t *)handle;
			ret = uv_tcp_bind(tcp, &addr->ip, 0);
176 177 178
		}
	}

179
	if (ret != 0) {
180
		io_deinit(handle);
181
		free(handle);
182 183
		return NULL;
	}
184 185 186 187

	/* Set current handle as a subrequest type. */
	struct session *session = handle->data;
	session_flags(session)->outgoing = true;
188
	/* Connect or issue query datagram */
189
	return handle;
190 191
}

192
static void ioreq_kill_pending(struct qr_task *task)
193
{
194
	for (uint16_t i = 0; i < task->pending_count; ++i) {
195
		session_kill_ioreq(task->pending[i], task);
196 197 198 199
	}
	task->pending_count = 0;
}

200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223
/** @cond This memory layout is internal to mempool.c, use only for debugging. */
#if defined(__SANITIZE_ADDRESS__)
struct mempool_chunk {
  struct mempool_chunk *next;
  size_t size;
};
static void mp_poison(struct mempool *mp, bool poison)
{
	if (!poison) { /* @note mempool is part of the first chunk, unpoison it first */
		kr_asan_unpoison(mp, sizeof(*mp));
	}
	struct mempool_chunk *chunk = mp->state.last[0];
	void *chunk_off = (void *)chunk - chunk->size;
	if (poison) {
		kr_asan_poison(chunk_off, chunk->size);
	} else {
		kr_asan_unpoison(chunk_off, chunk->size);
	}
}
#else
#define mp_poison(mp, enable)
#endif
/** @endcond */

224
/** Get a mempool.  (Recycle if possible.)  */
225
static inline struct mempool *pool_borrow(struct worker_ctx *worker)
226 227
{
	struct mempool *mp = NULL;
228 229 230 231
	if (worker->pool_mp.len > 0) {
		mp = array_tail(worker->pool_mp);
		array_pop(worker->pool_mp);
		mp_poison(mp, 0);
232 233 234 235 236 237
	} else { /* No mempool on the freelist, create new one */
		mp = mp_new (4 * CPU_PAGE_SIZE);
	}
	return mp;
}

238
/** Return a mempool.  (Cache them up to some count.) */
239 240
static inline void pool_release(struct worker_ctx *worker, struct mempool *mp)
{
241
	if (worker->pool_mp.len < MP_FREELIST_SIZE) {
242
		mp_flush(mp);
243
		array_push(worker->pool_mp, mp);
244
		mp_poison(mp, 1);
245 246 247 248 249
	} else {
		mp_delete(mp);
	}
}

250 251 252 253 254 255 256 257 258 259 260 261
/** Create a key for an outgoing subrequest: qname, qclass, qtype.
 * @param key Destination buffer for key size, MUST be SUBREQ_KEY_LEN or larger.
 * @return key length if successful or an error
 */
static const size_t SUBREQ_KEY_LEN = KR_RRKEY_LEN;
static int subreq_key(char *dst, knot_pkt_t *pkt)
{
	assert(pkt);
	return kr_rrkey(dst, knot_pkt_qclass(pkt), knot_pkt_qname(pkt),
			knot_pkt_qtype(pkt), knot_pkt_qtype(pkt));
}

262 263 264 265 266 267 268
/** Create and initialize a request_ctx (on a fresh mempool).
 *
 * handle and addr point to the source of the request, and they are NULL
 * in case the request didn't come from network.
 */
static struct request_ctx *request_create(struct worker_ctx *worker,
					  uv_handle_t *handle,
269 270
					  const struct sockaddr *addr,
					  uint32_t uid)
271
{
272
	knot_mm_t pool = {
273
		.ctx = pool_borrow(worker),
274
		.alloc = (knot_mm_alloc_t) mp_alloc
275
	};
276

277 278 279 280
	/* Create request context */
	struct request_ctx *ctx = mm_alloc(&pool, sizeof(*ctx));
	if (!ctx) {
		pool_release(worker, pool.ctx);
281 282
		return NULL;
	}
283

284 285 286 287
	memset(ctx, 0, sizeof(*ctx));

	/* TODO Relocate pool to struct request */
	ctx->worker = worker;
288 289
	struct session *s = handle ? handle->data : NULL;
	if (s) {
290
		assert(session_flags(s)->outgoing == false);
291
	}
292
	ctx->source.session = s;
293 294 295

	struct kr_request *req = &ctx->req;
	req->pool = pool;
296
	req->vars_ref = LUA_NOREF;
297
	req->uid = uid;
298
	req->daemon_context = worker;
299

300
	/* Remember query source addr */
301 302 303
	if (!addr || (addr->sa_family != AF_INET && addr->sa_family != AF_INET6)) {
		ctx->source.addr.ip.sa_family = AF_UNSPEC;
	} else {
304
		memcpy(&ctx->source.addr, addr, kr_sockaddr_len(addr));
305
		ctx->req.qsource.addr = &ctx->source.addr.ip;
306
	}
307 308 309 310 311

	worker->stats.rconcurrent += 1;

	if (!handle) {
		return ctx;
312
	}
313

314
	/* Remember the destination address. */
315 316 317 318 319 320
	int addr_len = sizeof(ctx->source.dst_addr);
	struct sockaddr *dst_addr = &ctx->source.dst_addr.ip;
	ctx->source.dst_addr.ip.sa_family = AF_UNSPEC;
	if (handle->type == UV_UDP) {
		if (uv_udp_getsockname((uv_udp_t *)handle, dst_addr, &addr_len) == 0) {
			req->qsource.dst_addr = dst_addr;
321
		}
322
		req->qsource.flags.tcp = false;
323
		req->qsource.flags.tls = false;
324 325 326
	} else if (handle->type == UV_TCP) {
		if (uv_tcp_getsockname((uv_tcp_t *)handle, dst_addr, &addr_len) == 0) {
			req->qsource.dst_addr = dst_addr;
327
		}
328
		req->qsource.flags.tcp = true;
329
		req->qsource.flags.tls = s && session_flags(s)->has_tls;
330
	}
331 332

	return ctx;
333 334
}

335 336
/** More initialization, related to the particular incoming query/packet. */
static int request_start(struct request_ctx *ctx, knot_pkt_t *query)
337
{
338 339 340 341 342
	assert(query && ctx);
	size_t answer_max = KNOT_WIRE_MIN_PKTSIZE;
	struct kr_request *req = &ctx->req;

	/* source.session can be empty if request was generated by kresd itself */
343 344
	struct session *s = ctx->source.session;
	if (!s || session_get_handle(s)->type == UV_TCP) {
345 346 347 348
		answer_max = KNOT_WIRE_MAX_PKTSIZE;
	} else if (knot_pkt_has_edns(query)) { /* EDNS */
		answer_max = MAX(knot_edns_get_payload(query->opt_rr),
				 KNOT_WIRE_MIN_PKTSIZE);
349
	}
350
	req->qsource.size = query->size;
351 352 353
	if (knot_pkt_has_tsig(query)) {
		req->qsource.size += query->tsig_wire.len;
	}
354

355 356
	knot_pkt_t *answer = knot_pkt_new(NULL, answer_max, &req->pool);
	if (!answer) { /* Failed to allocate answer */
357 358 359
		return kr_error(ENOMEM);
	}

360 361 362
	knot_pkt_t *pkt = knot_pkt_new(NULL, req->qsource.size, &req->pool);
	if (!pkt) {
		return kr_error(ENOMEM);
363
	}
364 365 366

	int ret = knot_pkt_copy(pkt, query);
	if (ret != KNOT_EOK && ret != KNOT_ETRAIL) {
367
		return kr_error(ENOMEM);
368
	}
369 370
	req->qsource.packet = pkt;

371 372 373
	/* Start resolution */
	struct worker_ctx *worker = ctx->worker;
	struct engine *engine = worker->engine;
374
	kr_resolve_begin(req, &engine->resolver, answer);
375 376 377 378 379 380 381 382 383 384 385
	worker->stats.queries += 1;
	/* Throttle outbound queries only when high pressure */
	if (worker->stats.concurrent < QUERY_RATE_THRESHOLD) {
		req->options.NO_THROTTLE = true;
	}
	return kr_ok();
}

static void request_free(struct request_ctx *ctx)
{
	struct worker_ctx *worker = ctx->worker;
386 387 388 389 390 391 392 393 394 395 396 397 398 399
	/* Dereference any Lua vars table if exists */
	if (ctx->req.vars_ref != LUA_NOREF) {
		lua_State *L = worker->engine->L;
		/* Get worker variables table */
		lua_rawgeti(L, LUA_REGISTRYINDEX, worker->vars_table_ref);
		/* Get next free element (position 0) and store it under current reference (forming a list) */
		lua_rawgeti(L, -1, 0);
		lua_rawseti(L, -2, ctx->req.vars_ref);
		/* Set current reference as the next free element */
		lua_pushinteger(L, ctx->req.vars_ref);
		lua_rawseti(L, -2, 0);
		lua_pop(L, 1);
		ctx->req.vars_ref = LUA_NOREF;
	}
400
	/* Return mempool to ring or free it if it's full */
401
	pool_release(worker, ctx->req.pool.ctx);
402
	/* @note The 'task' is invalidated from now on. */
Marek Vavruša's avatar
Marek Vavruša committed
403
	/* Decommit memory every once in a while */
404
	static int mp_delete_count = 0;
405 406 407
	if (++mp_delete_count == 100000) {
		lua_gc(worker->engine->L, LUA_GCCOLLECT, 0);
#if defined(__GLIBC__) && defined(_GNU_SOURCE)
Marek Vavruša's avatar
Marek Vavruša committed
408
		malloc_trim(0);
409
#endif
Marek Vavruša's avatar
Marek Vavruša committed
410
		mp_delete_count = 0;
411
	}
412
	worker->stats.rconcurrent -= 1;
413
}
414

415 416 417 418 419 420 421 422
static struct qr_task *qr_task_create(struct request_ctx *ctx)
{
	/* How much can client handle? */
	struct engine *engine = ctx->worker->engine;
	size_t pktbuf_max = KR_EDNS_PAYLOAD;
	if (engine->resolver.opt_rr) {
		pktbuf_max = MAX(knot_edns_get_payload(engine->resolver.opt_rr),
				 pktbuf_max);
423 424
	}

425 426 427 428
	/* Create resolution task */
	struct qr_task *task = mm_alloc(&ctx->req.pool, sizeof(*task));
	if (!task) {
		return NULL;
429
	}
430
	memset(task, 0, sizeof(*task)); /* avoid accidentally unintialized fields */
431

432 433 434 435 436
	/* Create packet buffers for answer and subrequests */
	knot_pkt_t *pktbuf = knot_pkt_new(NULL, pktbuf_max, &ctx->req.pool);
	if (!pktbuf) {
		mm_free(&ctx->req.pool, task);
		return NULL;
437
	}
438
	pktbuf->size = 0;
439

440 441 442 443
	task->ctx = ctx;
	task->pktbuf = pktbuf;
	array_init(task->waiting);
	task->refs = 0;
444 445 446 447
	assert(ctx->task == NULL);
	ctx->task = task;
	/* Make the primary reference to task. */
	qr_task_ref(task);
448
	task->creation_time = kr_now();
449 450
	ctx->worker->stats.concurrent += 1;
	return task;
451 452
}

453 454 455 456 457 458 459 460 461
/* This is called when the task refcount is zero, free memory. */
static void qr_task_free(struct qr_task *task)
{
	struct request_ctx *ctx = task->ctx;

	assert(ctx);

	struct worker_ctx *worker = ctx->worker;

462
	if (ctx->task == NULL) {
463 464 465 466 467 468 469
		request_free(ctx);
	}

	/* Update stats */
	worker->stats.concurrent -= 1;
}

470 471 472
/*@ Register new qr_task within session. */
static int qr_task_register(struct qr_task *task, struct session *session)
{
473
	assert(!session_flags(session)->outgoing && session_get_handle(session)->type == UV_TCP);
474 475 476 477 478 479 480 481 482 483 484

	session_tasklist_add(session, task);

	struct request_ctx *ctx = task->ctx;
	assert(ctx && (ctx->source.session == NULL || ctx->source.session == session));
	ctx->source.session = session;
	/* Soft-limit on parallel queries, there is no "slow down" RCODE
	 * that we could use to signalize to client, but we can stop reading,
	 * an in effect shrink TCP window size. To get more precise throttling,
	 * we would need to copy remainder of the unread buffer and reassemble
	 * when resuming reading. This is NYI.  */
485 486 487 488
	if (session_tasklist_get_len(session) >= task->ctx->worker->tcp_pipeline_max &&
	    !session_flags(session)->throttled && !session_flags(session)->closing) {
		session_stop_read(session);
		session_flags(session)->throttled = true;
489 490 491 492 493
	}

	return 0;
}

494
static void qr_task_complete(struct qr_task *task)
495
{
496
	struct request_ctx *ctx = task->ctx;
497

498
	/* Kill pending I/O requests */
499
	ioreq_kill_pending(task);
500 501
	assert(task->waiting.len == 0);
	assert(task->leading == false);
502

503 504
	struct session *s = ctx->source.session;
	if (s) {
505
		assert(!session_flags(s)->outgoing && session_waitinglist_is_empty(s));
506
		ctx->source.session = NULL;
507
		session_tasklist_del(s, task);
Grigorii Demidov's avatar
Grigorii Demidov committed
508
	}
509

510
	/* Release primary reference to task. */
511 512 513 514
	if (ctx->task == task) {
		ctx->task = NULL;
		qr_task_unref(task);
	}
515 516
}

517
/* This is called when we send subrequest / answer */
518
static int qr_task_on_send(struct qr_task *task, uv_handle_t *handle, int status)
519
{
520

521 522 523 524 525
	if (task->finished) {
		assert(task->leading == false);
		qr_task_complete(task);
	}

526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546
	if (!handle || handle->type != UV_TCP) {
		return status;
	}

	struct session* s = handle->data;
	assert(s);
	if (status != 0) {
		session_tasklist_del(s, task);
	}

	if (session_flags(s)->outgoing || session_flags(s)->closing) {
		return status;
	}

	struct worker_ctx *worker = task->ctx->worker;
	if (session_flags(s)->throttled &&
	    session_tasklist_get_len(s) < worker->tcp_pipeline_max/2) {
	   /* Start reading again if the session is throttled and
	    * the number of outgoing requests is below watermark. */
		session_start_read(s);
		session_flags(s)->throttled = false;
547
	}
548

549
	return status;
550 551
}

552 553 554
static void on_send(uv_udp_send_t *req, int status)
{
	struct qr_task *task = req->data;
555 556
	uv_handle_t *h = (uv_handle_t *)req->handle;
	qr_task_on_send(task, h, status);
557
	qr_task_unref(task);
558
	free(req);
559
}
560 561

static void on_write(uv_write_t *req, int status)
562 563
{
	struct qr_task *task = req->data;
564 565
	uv_handle_t *h = (uv_handle_t *)req->handle;
	qr_task_on_send(task, h, status);
566
	qr_task_unref(task);
567
	free(req);
568 569
}

570
static int qr_task_send(struct qr_task *task, struct session *session,
571
			struct sockaddr *addr, knot_pkt_t *pkt)
572
{
573 574
	if (!session) {
		return qr_task_on_send(task, NULL, kr_error(EIO));
575
	}
576

577
	int ret = 0;
578
	struct request_ctx *ctx = task->ctx;
579

580 581
	uv_handle_t *handle = session_get_handle(session);
	assert(handle && handle->data == session);
582 583 584
	const bool is_stream = handle->type == UV_TCP;
	if (!is_stream && handle->type != UV_UDP) abort();

585 586 587 588 589 590 591 592
	if (addr == NULL) {
		addr = session_get_peer(session);
	}

	if (pkt == NULL) {
		pkt = worker_task_get_pktbuf(task);
	}

593
	if (session_flags(session)->outgoing && handle->type == UV_TCP) {
594 595
		size_t try_limit = session_tasklist_get_len(session) + 1;
		uint16_t msg_id = knot_wire_get_id(pkt->wire);
596
		size_t try_count = 0;
597 598 599 600 601 602
		while (session_tasklist_find_msgid(session, msg_id) &&
		       try_count <= try_limit) {
			++msg_id;
			++try_count;
		}
		if (try_count > try_limit) {
603
			return kr_error(ENOENT);
604 605 606 607
		}
		worker_task_pkt_set_msgid(task, msg_id);
	}

608 609 610 611 612
	uv_handle_t *ioreq = malloc(is_stream ? sizeof(uv_write_t) : sizeof(uv_udp_send_t));
	if (!ioreq) {
		return qr_task_on_send(task, handle, kr_error(ENOMEM));
	}

613 614 615
	/* Pending ioreq on current task */
	qr_task_ref(task);

616
	struct worker_ctx *worker = ctx->worker;
617
	/* Send using given protocol */
618 619
	assert(!session_flags(session)->closing);
	if (session_flags(session)->has_tls) {
620 621
		uv_write_t *write_req = (uv_write_t *)ioreq;
		write_req->data = task;
622
		ret = tls_write(write_req, handle, pkt, &on_write);
623
	} else if (handle->type == UV_UDP) {
624
		uv_udp_send_t *send_req = (uv_udp_send_t *)ioreq;
625
		uv_buf_t buf = { (char *)pkt->wire, pkt->size };
626 627 628 629
		send_req->data = task;
		ret = uv_udp_send(send_req, (uv_udp_t *)handle, &buf, 1, addr, &on_send);
	} else if (handle->type == UV_TCP) {
		uv_write_t *write_req = (uv_write_t *)ioreq;
630 631 632 633 634
		uint16_t pkt_size = htons(pkt->size);
		uv_buf_t buf[2] = {
			{ (char *)&pkt_size, sizeof(pkt_size) },
			{ (char *)pkt->wire, pkt->size }
		};
635
		write_req->data = task;
636
		ret = uv_write(write_req, (uv_stream_t *)handle, buf, 2, &on_write);
637 638
	} else {
		assert(false);
639
	}
640

641
	if (ret == 0) {
642
		session_touch(session);
643 644 645
		if (session_flags(session)->outgoing) {
			session_tasklist_add(session, task);
		}
646 647
		if (worker->too_many_open &&
		    worker->stats.rconcurrent <
648
			worker->rconcurrent_highwatermark - 10) {
649 650
			worker->too_many_open = false;
		}
651
	} else {
652
		free(ioreq);
653
		qr_task_unref(task);
654 655 656
		if (ret == UV_EMFILE) {
			worker->too_many_open = true;
			worker->rconcurrent_highwatermark = worker->stats.rconcurrent;
657
			ret = kr_error(UV_EMFILE);
658
		}
659
	}
660

661
	/* Update statistics */
662 663
	if (session_flags(session)->outgoing && addr) {
		if (session_flags(session)->has_tls)
664 665
			worker->stats.tls += 1;
		else if (handle->type == UV_UDP)
666
			worker->stats.udp += 1;
667
		else
668
			worker->stats.tcp += 1;
669

670
		if (addr->sa_family == AF_INET6)
671
			worker->stats.ipv6 += 1;
672
		else if (addr->sa_family == AF_INET)
673
			worker->stats.ipv4 += 1;
674
	}
675
	return ret;
676 677
}

678 679
static int session_tls_hs_cb(struct session *session, int status)
{
680
	assert(session_flags(session)->outgoing);
681 682 683 684 685
	uv_handle_t *handle = session_get_handle(session);
	uv_loop_t *loop = handle->loop;
	struct worker_ctx *worker = loop->data;
	struct sockaddr *peer = session_get_peer(session);
	int deletion_res = worker_del_tcp_waiting(worker, peer);
686
	int ret = kr_ok();
687

688
	if (status) {
689
		kr_nsrep_update_rtt(NULL, peer, KR_NS_DEAD,
690 691
				    worker->engine->resolver.cache_rtt,
				    KR_NS_UPDATE_NORESET);
692 693 694 695
		return ret;
	}

	/* handshake was completed successfully */
696
	struct tls_client_ctx_t *tls_client_ctx = session_tls_get_client_ctx(session);
697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714
	struct tls_client_paramlist_entry *tls_params = tls_client_ctx->params;
	gnutls_session_t tls_session = tls_client_ctx->c.tls_session;
	if (gnutls_session_is_resumed(tls_session) != 0) {
		kr_log_verbose("[tls_client] TLS session has resumed\n");
	} else {
		kr_log_verbose("[tls_client] TLS session has not resumed\n");
		/* session wasn't resumed, delete old session data ... */
		if (tls_params->session_data.data != NULL) {
			gnutls_free(tls_params->session_data.data);
			tls_params->session_data.data = NULL;
			tls_params->session_data.size = 0;
		}
		/* ... and get the new session data */
		gnutls_datum_t tls_session_data = { NULL, 0 };
		ret = gnutls_session_get_data2(tls_session, &tls_session_data);
		if (ret == 0) {
			tls_params->session_data = tls_session_data;
		}
715
	}
716

717 718 719 720 721 722 723 724 725 726 727 728 729
	ret = kr_ok();
	if (deletion_res == kr_ok()) {
		/* peer was in the waiting list, add to the connected list. */
		ret = worker_add_tcp_connected(worker, peer, session);
	} else {
		/* peer wasn't in the waiting list.
		 * In this case it must be successful rehandshake.
		 * Peer must be already in the connected list. */
		const char *key = tcpsess_key(peer);
		assert(key);
		assert(map_contains(&worker->tcp_connected, key) != 0);
	}
	if (ret == kr_ok()) {
730 731 732 733 734 735 736 737
		while (!session_waitinglist_is_empty(session)) {
			struct qr_task *t = session_waitinglist_get(session);
			ret = qr_task_send(t, session, NULL, NULL);
			if (ret != 0) {
				break;
			}
			session_waitinglist_pop(session, true);
		}
738 739 740 741 742 743 744 745 746
	} else {
		ret = kr_error(EINVAL);
	}

	if (ret != kr_ok()) {
		/* Something went wrong.
		 * Session isn't in the list of waiting sessions,
		 * or addition to the list of connected sessions failed,
		 * or write to upstream failed. */
747
		worker_del_tcp_connected(worker, peer);
748
		session_waitinglist_finalize(session, KR_STATE_FAIL);
749
		assert(session_tasklist_is_empty(session));
750
		session_close(session);
751
	} else {
752
		session_timer_stop(session);
753
		session_timer_start(session, tcp_timeout_trigger,
754
				    MAX_TCP_INACTIVITY, MAX_TCP_INACTIVITY);
755 756 757 758
	}
	return kr_ok();
}

759

760 761 762
static struct kr_query *task_get_last_pending_query(struct qr_task *task)
{
	if (!task || task->ctx->req.rplan.pending.len == 0) {
763 764 765 766 767 768
		return NULL;
	}

	return array_tail(task->ctx->req.rplan.pending);
}

769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784
static int send_waiting(struct session *session)
{
	int ret = 0;
	while (!session_waitinglist_is_empty(session)) {
		struct qr_task *t = session_waitinglist_get(session);
		ret = qr_task_send(t, session, NULL, NULL);
		if (ret != 0) {
			session_waitinglist_finalize(session, KR_STATE_FAIL);
			session_tasklist_finalize(session, KR_STATE_FAIL);
			session_close(session);
			break;
		}
		session_waitinglist_pop(session, true);
	}
	return ret;
}
785

786
static void on_connect(uv_connect_t *req, int status)
787
{
788
	struct worker_ctx *worker = get_worker();
789
	uv_stream_t *handle = req->handle;
790
	struct session *session = handle->data;
791
	struct sockaddr *peer = session_get_peer(session);
792
	free(req);
793

794
	assert(session_flags(session)->outgoing);
795 796

	if (status == UV_ECANCELED) {
797
		worker_del_tcp_waiting(worker, peer);
798
		assert(session_is_empty(session) && session_flags(session)->closing);
799 800 801
		return;
	}

802
	if (session_flags(session)->closing) {
803 804
		worker_del_tcp_waiting(worker, peer);
		assert(session_is_empty(session));
805 806 807 808
		return;
	}

	if (status != 0) {
809 810
		worker_del_tcp_waiting(worker, peer);
		assert(session_tasklist_is_empty(session));
811
		session_waitinglist_retry(session, false);
812 813 814 815
		session_close(session);
		return;
	}

816
	if (!session_flags(session)->has_tls) {
817 818
		/* if there is a TLS, session still waiting for handshake,
		 * otherwise remove it from waiting list */
819
		if (worker_del_tcp_waiting(worker, peer) != 0) {
820 821
			/* session isn't in list of waiting queries, *
			 * something gone wrong */
822 823
			session_waitinglist_finalize(session, KR_STATE_FAIL);
			assert(session_tasklist_is_empty(session));
824 825 826 827 828
			session_close(session);
			return;
		}
	}

829
	struct qr_task *task = session_waitinglist_get(session);
830
	struct kr_query *qry = task_get_last_pending_query(task);
831
	WITH_VERBOSE (qry) {
832 833 834 835
		struct sockaddr *peer = session_get_peer(session);
		char peer_str[INET6_ADDRSTRLEN];
		inet_ntop(peer->sa_family, kr_inaddr(peer), peer_str, sizeof(peer_str));
		VERBOSE_MSG(qry, "=> connected to '%s'\n", peer_str);
836 837
	}

838
	session_flags(session)->connected = true;
839
	session_start_read(session);
840 841

	int ret = kr_ok();
842
	if (session_flags(session)->has_tls) {
843 844
		struct tls_client_ctx_t *tls_ctx = session_tls_get_client_ctx(session);
		ret = tls_client_connect_start(tls_ctx, session, session_tls_hs_cb);
845
		if (ret == kr_error(EAGAIN)) {
846 847
			session_timer_stop(session);
			session_timer_start(session, tcp_timeout_trigger,
848
					    MAX_TCP_INACTIVITY, MAX_TCP_INACTIVITY);
849 850
			return;
		}
851 852
	} else {
		worker_add_tcp_connected(worker, peer, session);
853
	}
854 855 856 857 858

	ret = send_waiting(session);
	if (ret != 0) {
		worker_del_tcp_connected(worker, peer);
		return;
859
	}
860

861 862
	session_timer_stop(session);
	session_timer_start(session, tcp_timeout_trigger,
863
			    MAX_TCP_INACTIVITY, MAX_TCP_INACTIVITY);
864 865
}

866
static void on_tcp_connect_timeout(uv_timer_t *timer)
867
{
868 869 870
	struct session *session = timer->data;

	uv_timer_stop(timer);
871
	struct worker_ctx *worker = get_worker();
872

873
	assert (session_tasklist_is_empty(session));
874

875 876
	struct sockaddr *peer = session_get_peer(session);
	worker_del_tcp_waiting(worker, peer);
877

878
	struct qr_task *task = session_waitinglist_get(session);
879
	struct kr_query *qry = task_get_last_pending_query(task);
880
	WITH_VERBOSE (qry) {
881 882 883
		char peer_str[INET6_ADDRSTRLEN];
		inet_ntop(peer->sa_family, kr_inaddr(peer), peer_str, sizeof(peer_str));
		VERBOSE_MSG(qry, "=> connection to '%s' failed\n", peer_str);
884
	}
885

886
	kr_nsrep_update_rtt(NULL, peer, KR_NS_DEAD,
887 888
			    worker->engine->resolver.cache_rtt,
			    KR_NS_UPDATE_NORESET);
889

890 891 892
	worker->stats.timeout += session_waitinglist_get_len(session);
	session_waitinglist_retry(session, true);
	assert (session_tasklist_is_empty(session));
893
	session_close(session);
894 895 896
}

/* This is called when I/O timeouts */
897
static void on_udp_timeout(uv_timer_t *timer)
898
{
899
	struct session *session = timer->data;
900 901 902
	assert(session_get_handle(session)->data == session);
	assert(session_tasklist_get_len(session) == 1);
	assert(session_waitinglist_is_empty(session));
903 904

	uv_timer_stop(timer);
905 906

	/* Penalize all tried nameservers with a timeout. */
907
	struct qr_task *task = session_tasklist_get_first(session);
908
	struct worker_ctx *worker = task->ctx->worker;
909
	if (task->leading && task->pending_count > 0) {
910
		struct kr_query *qry = array_tail(task->ctx->req.rplan.pending);
911 912 913
		struct sockaddr_in6 *addrlist = (struct sockaddr_in6 *)task->addrlist;
		for (uint16_t i = 0; i < MIN(task->pending_count, task->addrlist_count); ++i) {
			struct sockaddr *choice = (struct sockaddr *)(&addrlist[i]);
914
			WITH_VERBOSE(qry) {
915 916
				char addr_str[INET6_ADDRSTRLEN];
				inet_ntop(choice->sa_family, kr_inaddr(choice), addr_str, sizeof(addr_str));
917
				VERBOSE_MSG(qry, "=> server: '%s' flagged as 'bad'\n", addr_str);
918
			}
919
			kr_nsrep_update_rtt(&qry->ns, choice, KR_NS_DEAD,
920 921
					    worker->engine->resolver.cache_rtt,
					    KR_NS_UPDATE_NORESET);
922 923 924 925 926
		}
	}
	task->timeouts += 1;
	worker->stats.timeout += 1;
	qr_task_step(task, NULL, NULL);
927 928
}

929
static uv_handle_t *retransmit(struct qr_task *task)
930
{
931
	uv_handle_t *ret = NULL;
932
	if (task && task->addrlist && task->addrlist_count > 0) {
933
		struct sockaddr_in6 *choice = &((struct sockaddr_in6 *)task->addrlist)[task->addrlist_turn];
Grigorii Demidov's avatar
Grigorii Demidov committed
934 935 936
		if (!choice) {
			return ret;
		}
937 938 939
		if (task->pending_count >= MAX_PENDING) {
			return ret;
		}
940 941 942 943 944
		/* Checkout answer before sending it */
		struct request_ctx *ctx = task->ctx;
		if (kr_resolve_checkout(&ctx->req, NULL, (struct sockaddr *)choice, SOCK_DGRAM, task->pktbuf) != 0) {
			return ret;
		}
945
		ret = ioreq_spawn(ctx->worker, SOCK_DGRAM, choice->sin6_family, false);
946 947 948 949 950
		if (!ret) {
			return ret;
		}
		struct sockaddr *addr = (struct sockaddr *)choice;
		struct session *session = ret->data;
951
		struct sockaddr *peer = session_get_peer(session);
952
		assert (peer->sa_family == AF_UNSPEC && session_flags(session)->outgoing);
953
		memcpy(peer, addr, kr_sockaddr_len(addr));
954 955 956 957 958
		if (qr_task_send(task, session, (struct sockaddr *)choice,
				 task->pktbuf) != 0) {
			session_close(session);
			ret = NULL;
		} else {
959
			task->pending[task->pending_count] = session;
960
			task->pending_count += 1;
961 962
			task->addrlist_turn = (task->addrlist_turn + 1) %
					      task->addrlist_count; /* Round robin */
963
			session_start_read(session); /* Start reading answer */
964 965
		}
	}
966
	return ret;
967 968 969 970
}

static void on_retransmit(uv_timer_t *req)
{
971
	struct session *session = req->data;
972
	assert(session_tasklist_get_len(session) == 1);
973 974

	uv_timer_stop(req);
975
	struct qr_task *task = session_tasklist_get_first(session);
976
	if (retransmit(task) == NULL) {
977 978
		/* Not possible to spawn request, start timeout timer with remaining deadline. */
		uint64_t timeout = KR_CONN_RTT_MAX - task->pending_count * KR_CONN_RETRY;
979
		uv_timer_start(req, on_udp_timeout, timeout, 0);
980 981
	} else {
		uv_timer_start(req, on_retransmit, KR_CONN_RETRY, 0);
982
	}
983 984
}

985
static void subreq_finalize(struct qr_task *task, const struct sockaddr *packet_source, knot_pkt_t *pkt)
986
{
987 988 989
	if (!task || task->finished) {
		return;
	}
990
	/* Close pending timer */
991
	ioreq_kill_pending(task);
992
	/* Clear from outgoing table. */
993 994
	if (!task->leading)
		return;
995 996 997 998 999
	char key[SUBREQ_KEY_LEN];
	const int klen = subreq_key(key, task->pktbuf);
	if (klen > 0) {
		void *val_deleted;
		int ret = trie_del(task->ctx->worker->subreq_out, key, klen, &val_deleted);
1000
		assert(ret == KNOT_EOK && val_deleted == task); (void)ret;
1001 1002
	}
	/* Notify waiting tasks. */
1003
	struct kr_query *leader_qry = array_tail(task->ctx->req.rplan.pending);
1004 1005
	for (size_t i = task->waiting.len; i > 0; i--) {
		struct qr_task *follower = task->waiting.at[i - 1];
1006
		/* Reuse MSGID and 0x20 secret */
1007 1008
		if (follower->ctx->req.rplan.pending.len > 0) {
			struct kr_query *qry = array_tail(follower->ctx->req.rplan.pending);
1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022
			qry->id = leader_qry->id;
			qry->secret = leader_qry->secret;
			leader_qry->secret = 0; /* Next will be already decoded */
		}
		qr_task_step(follower, packet_source, pkt);
		qr_task_unref(follower);
	}
	task->waiting.len = 0;
	task->leading = false;
}

static void subreq_lead(struct qr_task *task)
{
	assert(task);
1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033
	char key[SUBREQ_KEY_LEN];
	const int klen = subreq_key(key, task->pktbuf);
	if (klen < 0)
		return;
	struct qr_task **tvp = (struct qr_task **)
		trie_get_ins(task->ctx->worker->subreq_out, key, klen);
	if (unlikely(!tvp))
		return; /*ENOMEM*/
	if (unlikely(*tvp != NULL)) {
		assert(false);
		return;
1034
	}
1035 1036
	*tvp = task;
	task->leading = true;
1037 1038 1039 1040 1041
}

static bool subreq_enqueue(struct qr_task *task)
{
	assert(task);
1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056
	char key[SUBREQ_KEY_LEN];
	const int klen = subreq_key(key, task->pktbuf);
	if (klen < 0)
		return false;
	struct qr_task **leader = (struct qr_task **)
		trie_get_try(task->ctx->worker->subreq_out, key, klen);
	if (!leader /*ENOMEM*/ || !*leader)
		return false;
	/* Enqueue itself to leader for this subrequest. */
	int ret = array_push_mm((*leader)->waiting, task,
				kr_memreserve, &(*leader)->ctx->req.pool);
	if (unlikely(ret < 0)) /*ENOMEM*/
		return false;
	qr_task_ref(task);
	return true;
1057 1058 1059 1060 1061
}

static int qr_task_finalize(struct qr_task *task, int state)
{
	assert(task && task->leading == false);
1062 1063 1064
	if (task->finished) {
		return 0;
	}
1065
	struct request_ctx *ctx = task->ctx;
1066
	struct session *source_session = ctx->source.session;
1067
	kr_resolve_finish(&ctx->req, state);
1068

1069
	task->finished = true;
1070
	if (source_session == NULL) {
1071 1072 1073 1074
		(void) qr_task_on_send(task, NULL, kr_error(EIO));
		return state == KR_STATE_DONE ? 0 : kr_error(EIO);
	}

1075 1076 1077
	/* Reference task as the callback handler can close it */
	qr_task_ref(task);

1078
	/* Send back answer */
1079
	assert(!session_flags(source_session)->closing);
1080
	assert(ctx->source.addr.ip.sa_family != AF_UNSPEC);
1081
	int res = qr_task_send(task, source_session,
1082 1083 1084
			       (struct sockaddr *)&ctx->source.addr,
			        ctx->req.answer);
	if (res != kr_ok()) {
1085
		(void) qr_task_on_send(task, NULL, kr_error(EIO));
1086
		/* Since source session is erroneous detach all tasks. */
1087
		while (!session_tasklist_is_empty(source_session)) {
1088
			struct qr_task *t = session_tasklist_del_first(source_session, false);
1089 1090 1091 1092 1093 1094
			struct request_ctx *c = t->ctx;
			assert(c->source.session == source_session);
			c->source.session = NULL;
			/* Don't finalize them as there can be other tasks
			 * waiting for answer to this particular task.
			 * (ie. task->leading is true) */
1095
			worker_task_unref(t);
1096 1097
		}
		session_close(source_session);
1098
	}
1099

1100 1101
	qr_task_unref(task);

1102
	return state == KR_STATE_DONE ? 0 : kr_error(EIO);
1103
}
1104

1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205
static int udp_task_step(struct qr_task *task,
			 const struct sockaddr *packet_source, knot_pkt_t *packet)
{
	struct request_ctx *ctx = task->ctx;
	struct kr_request *req = &ctx->req;

	/* If there is already outgoing query, enqueue to it. */
	if (subreq_enqueue(task)) {
		return kr_ok(); /* Will be notified when outgoing query finishes. */
	}
	/* Start transmitting */
	uv_handle_t *handle = retransmit(task);
	if (handle == NULL) {
		subreq_finalize(task, packet_source, packet);
		return qr_task_finalize(task, KR_STATE_FAIL);
	}
	/* Check current query NSLIST */
	struct kr_query *qry = array_tail(req->rplan.pending);
	assert(qry != NULL);
	/* Retransmit at default interval, or more frequently if the mean
	 * RTT of the server is better. If the server is glued, use default rate. */
	size_t timeout = qry->ns.score;
	if (timeout > KR_NS_GLUED) {
		/* We don't have information about variance in RTT, expect +10ms */
		timeout = MIN(qry->ns.score + 10, KR_CONN_RETRY);
	} else {
		timeout = KR_CONN_RETRY;
	}
	/* Announce and start subrequest.
	 * @note Only UDP can lead I/O as it doesn't touch 'task->pktbuf' for reassembly.
	 */
	subreq_lead(task);
	struct session *session = handle->data;
	assert(session_get_handle(session) == handle && (handle->type == UV_UDP));
	int ret = session_timer_start(session, on_retransmit, timeout, 0);
	/* Start next step with timeout, fatal if can't start a timer. */
	if (ret != 0) {
		subreq_finalize(task, packet_source, packet);
		return qr_task_finalize(task, KR_STATE_FAIL);
	}
	return kr_ok();
}

static int tcp_task_waiting_connection(struct session *session, struct qr_task *task)
{
	assert(session_flags(session)->outgoing);
	if (session_flags(session)->closing) {
		/* Something went wrong. Better answer with KR_STATE_FAIL.
		 * TODO: normally should not happen,
		 * consider possibility to transform this into
		 * assert(!session_flags(session)->closing). */
		return kr_error(EINVAL);
	}
	/* Add task to the end of list of waiting tasks.
	 * It will be notified in on_connect() or qr_task_on_send(). */
	int ret = session_waitinglist_push(session, task);
	if (ret < 0) {
		return kr_error(EINVAL);
	}
	return kr_ok();
}

static int tcp_task_existing_connection(struct session *session, struct qr_task *task)
{
	assert(session_flags(session)->outgoing);
	struct request_ctx *ctx = task->ctx;
	struct worker_ctx *worker = ctx->worker;

	if (session_flags(session)->closing) {
		/* Something went wrong. Better answer with KR_STATE_FAIL.
		 * TODO: normally should not happen,
		 * consider possibility to transform this into
		 * assert(!session_flags(session)->closing). */
		return kr_error(EINVAL);
	}

	/* If there are any unsent queries, send it first. */
	int ret = send_waiting(session);
	if (ret != 0) {
		return kr_error(EINVAL);
	}

	/* No unsent queries at that point. */
	if (session_tasklist_get_len(session) >= worker->tcp_pipeline_max) {
		/* Too many outstanding queries, answer with SERFVAIL, */
		return kr_error(EINVAL);
	}

	/* Send query to upstream. */
	ret = qr_task_send(task, session, NULL, NULL);
	if (ret != 0) {
		/* Error, finalize task with SERVFAIL and
		 * close connection to upstream. */
		session_tasklist_finalize(session, KR_STATE_FAIL);
		session_close(session);
		return kr_error(EINVAL);
	}

	return kr_ok();
}

1206
static int tcp_task_make_connection(struct qr_task *task, const struct sockaddr *addr)
1207 1208 1209 1210
{
	struct request_ctx *ctx = task->ctx;
	struct worker_ctx *worker = ctx->worker;

1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225
	/* Check if there must be TLS */
	struct engine *engine = worker->engine;
	struct network *net = &engine->net;
	const char *key = tcpsess_key(addr);
	struct tls_client_ctx_t *tls_ctx = NULL;
	struct tls_client_paramlist_entry *entry = map_get(&net->tls_client_params, key);
	if (entry) {
		/* Address is configured to be used with TLS.
		 * We need to allocate auxiliary data structure. */
		tls_ctx = tls_client_ctx_new(entry, worker);
		if (!tls_ctx) {
			return kr_error(EINVAL);
		}
	}

1226 1227
	uv_connect_t *conn = malloc(sizeof(uv_connect_t));
	if (!conn) {
1228
		tls_client_ctx_free(tls_ctx);
1229 1230
		return kr_error(EINVAL);
	}
1231 1232
	bool has_tls = (tls_ctx != NULL);
	uv_handle_t *client = ioreq_spawn(worker, SOCK_STREAM, addr->sa_family, has_tls);
1233
	if (!client) {
1234
		tls_client_ctx_free(tls_ctx);
1235 1236 1237
		free(conn);
		return kr_error(EINVAL);
	}
Grigorii Demidov's avatar