src/lib-smtp/smtp-client-transaction.c

/* Copyright (c) 2009-2018 Dovecot authors, see the included COPYING file */

#include "lib.h"
#include "llist.h"
#include "ioloop.h"
#include "net.h"
#include "istream.h"
#include "istream-crlf.h"
#include "ostream.h"
#include "str.h"
#include "str-sanitize.h"
#include "dns-lookup.h"

#include "smtp-common.h"
#include "smtp-address.h"
#include "smtp-params.h"
#include "smtp-client-private.h"
#include "smtp-client-command.h"
#include "smtp-client-transaction.h"

#include <ctype.h>

const char *const smtp_client_transaction_state_names[] = {
	"new",
	"mail_from",
	"rcpt_to",
	"data",
	"reset",
	"finished",
	"aborted"
};

static void
smtp_client_transaction_submit_more(struct smtp_client_transaction *trans);
static void
smtp_client_transaction_submit(struct smtp_client_transaction *trans,
			       bool start);

static void
smtp_client_transaction_try_complete(struct smtp_client_transaction *trans);

static void
smtp_client_transaction_send_data(struct smtp_client_transaction *trans);
static void
smtp_client_transaction_send_reset(struct smtp_client_transaction *trans);

/*
 * Sender
 */

static struct smtp_client_transaction_mail *
smtp_client_transaction_mail_new(struct smtp_client_transaction *trans,
				 const struct smtp_address *mail_from,
				 const struct smtp_params_mail *mail_params)
{
	struct smtp_client_transaction_mail *mail;
	pool_t pool;

	pool = pool_alloconly_create("smtp transaction mail", 512);
	mail = p_new(pool, struct smtp_client_transaction_mail, 1);
	mail->pool = pool;
	mail->trans = trans;
	mail->mail_from = smtp_address_clone(pool, mail_from);
	smtp_params_mail_copy(pool, &mail->mail_params, mail_params);

	DLLIST2_APPEND(&trans->mail_head, &trans->mail_tail, mail);
	if (trans->mail_send == NULL)
		trans->mail_send = mail;

	return mail;
}

static void
smtp_client_transaction_mail_free(struct smtp_client_transaction_mail **_mail)
{
	struct smtp_client_transaction_mail *mail = *_mail;
	struct smtp_client_transaction *trans = mail->trans;

	*_mail = NULL;

	if (mail->cmd_mail_from != NULL)
		smtp_client_command_abort(&mail->cmd_mail_from);
	DLLIST2_REMOVE(&trans->mail_head, &trans->mail_tail, mail);
	pool_unref(&mail->pool);
}

static void
smtp_client_transaction_mail_replied(
	struct smtp_client_transaction_mail **_mail,
	const struct smtp_reply *reply)
{
	struct smtp_client_transaction_mail *mail = *_mail;
	smtp_client_command_callback_t *mail_callback = mail->mail_callback;
	void *context = mail->context;

	mail->mail_callback = NULL;

	/* call the callback */
	if (mail_callback != NULL)
		mail_callback(reply, context);

	smtp_client_transaction_mail_free(_mail);
}

void smtp_client_transaction_mail_abort(
	struct smtp_client_transaction_mail **_mail)
{
	struct smtp_client_transaction_mail *mail = *_mail;
	struct smtp_client_transaction *trans = mail->trans;

	i_assert(trans->state <= SMTP_CLIENT_TRANSACTION_STATE_MAIL_FROM ||
		 trans->state == SMTP_CLIENT_TRANSACTION_STATE_ABORTED);

	smtp_client_transaction_mail_free(_mail);
}

static void
smtp_client_transaction_mail_fail_reply(
	struct smtp_client_transaction_mail **_mail,
	const struct smtp_reply *reply)
{
	struct smtp_client_transaction_mail *mail = *_mail;
	smtp_client_command_callback_t *callback = mail->mail_callback;
	void *context = mail->context;

	mail->mail_callback = NULL;

	if (callback != NULL)
		callback(reply, context);

	smtp_client_transaction_mail_free(_mail);
}

/*
 * Recipient
 */

static void
smtp_client_transaction_rcpt_update_event(
	struct smtp_client_transaction_rcpt *rcpt)
{
	const char *to = smtp_address_encode(rcpt->rcpt_to);

	event_set_append_log_prefix(rcpt->event,
		t_strdup_printf("rcpt <%s>: ", str_sanitize(to, 128)));
	event_add_str(rcpt->event, "rcpt_to", to);
	smtp_params_rcpt_add_to_event(&rcpt->rcpt_params, rcpt->event);
}

static struct smtp_client_transaction_rcpt *
smtp_client_transaction_rcpt_new(
	struct smtp_client_transaction *trans, pool_t pool,
	const struct smtp_address *rcpt_to,
	const struct smtp_params_rcpt *rcpt_params)
{
	struct smtp_client_transaction_rcpt *rcpt;

	pool_ref(pool);

	rcpt = p_new(pool, struct smtp_client_transaction_rcpt, 1);
	rcpt->pool = pool;
	rcpt->trans = trans;
	rcpt->rcpt_to = smtp_address_clone(pool, rcpt_to);
	smtp_params_rcpt_copy(pool, &rcpt->rcpt_params, rcpt_params);

	DLLIST2_APPEND(&trans->rcpts_queue_head, &trans->rcpts_queue_tail,
		       rcpt);
	trans->rcpts_queue_count++;
	rcpt->queued = TRUE;
	if (trans->rcpts_send == NULL)
		trans->rcpts_send = rcpt;

	rcpt->event = event_create(trans->event);
	smtp_client_transaction_rcpt_update_event(rcpt);

	trans->rcpts_total++;

	return rcpt;
}

static void
smtp_client_transaction_rcpt_free(
	struct smtp_client_transaction_rcpt **_rcpt)
{
	struct smtp_client_transaction_rcpt *rcpt = *_rcpt;
	struct smtp_client_transaction *trans = rcpt->trans;

	*_rcpt = NULL;

	if (trans->rcpts_send == rcpt)
		trans->rcpts_send = rcpt->next;
	if (trans->rcpts_data == rcpt)
		trans->rcpts_data = rcpt->next;
	if (rcpt->queued) {
		DLLIST2_REMOVE(&trans->rcpts_queue_head,
			       &trans->rcpts_queue_tail, rcpt);
		trans->rcpts_queue_count--;
	} else {
		DLLIST2_REMOVE(&trans->rcpts_head,
			       &trans->rcpts_tail, rcpt);
		trans->rcpts_count--;
	}

	if (!rcpt->finished) {
		struct smtp_reply failure;

		trans->rcpts_aborted++;

		smtp_reply_init(&failure,
				SMTP_CLIENT_COMMAND_ERROR_ABORTED,
				"Aborted");
		failure.enhanced_code = SMTP_REPLY_ENH_CODE(9, 0, 0);

		struct event_passthrough *e =
			event_create_passthrough(rcpt->event)->
			set_name("smtp_client_transaction_rcpt_finished");
		smtp_reply_add_to_event(&failure, e);
		e_debug(e->event(), "Aborted");
	}

	event_unref(&rcpt->event);

	if (rcpt->queued || rcpt->external_pool) {
		i_assert(rcpt->pool != NULL);
		pool_unref(&rcpt->pool);
	}
}

static void
smtp_client_transaction_rcpt_approved(
	struct smtp_client_transaction_rcpt **_rcpt)
{
	struct smtp_client_transaction_rcpt *prcpt = *_rcpt;
	struct smtp_client_transaction *trans = prcpt->trans;
	struct smtp_client_transaction_rcpt *rcpt;
	pool_t pool;

	i_assert(prcpt->queued);

	if (prcpt->external_pool) {
		/* allocated externally; just remove it from the queue */
		prcpt->queued = FALSE;
		if (trans->rcpts_send == prcpt)
			trans->rcpts_send = prcpt->next;
		DLLIST2_REMOVE(&trans->rcpts_queue_head,
			       &trans->rcpts_queue_tail, prcpt);
		trans->rcpts_queue_count--;

		rcpt = prcpt;
	} else {
		/* move to transaction pool */
		pool = trans->pool;
		rcpt = p_new(pool, struct smtp_client_transaction_rcpt, 1);
		rcpt->trans = trans;
		rcpt->rcpt_to = smtp_address_clone(pool, prcpt->rcpt_to);
		smtp_params_rcpt_copy(pool, &rcpt->rcpt_params,
				      &prcpt->rcpt_params);
		rcpt->data_callback = prcpt->data_callback;
		rcpt->data_context = prcpt->data_context;

		rcpt->event = prcpt->event;
		event_ref(rcpt->event);

		/* free the old object, thereby removing it from the queue */
		smtp_client_transaction_rcpt_free(&prcpt);
	}

	/* recipient is approved */
	DLLIST2_APPEND(&trans->rcpts_head, &trans->rcpts_tail, rcpt);
	trans->rcpts_count++;
	if (trans->rcpts_data == NULL)
		trans->rcpts_data = trans->rcpts_head;

	*_rcpt = rcpt;
}

static void
smtp_client_transaction_rcpt_denied(
	struct smtp_client_transaction_rcpt **_rcpt,
	const struct smtp_reply *reply)
{
	struct smtp_client_transaction_rcpt *prcpt = *_rcpt;
	struct smtp_client_transaction *trans = prcpt->trans;

	*_rcpt = NULL;

	trans->rcpts_denied++;
	trans->rcpts_failed++;

	struct event_passthrough *e =
		event_create_passthrough(prcpt->event)->
		set_name("smtp_client_transaction_rcpt_finished");
	smtp_reply_add_to_event(reply, e);
	e_debug(e->event(), "Denied");

	/* not pending anymore */
	smtp_client_transaction_rcpt_free(&prcpt);
}

static void
smtp_client_transaction_rcpt_replied(
	struct smtp_client_transaction_rcpt **_rcpt,
	const struct smtp_reply *reply)
{
	struct smtp_client_transaction_rcpt *rcpt = *_rcpt;
	bool success = smtp_reply_is_success(reply);
	smtp_client_command_callback_t *rcpt_callback = rcpt->rcpt_callback;
	void *context = rcpt->context;

	rcpt->rcpt_callback = NULL;

	if (rcpt->finished)
		return;
	rcpt->finished = !success;

	if (success)
		smtp_client_transaction_rcpt_approved(_rcpt);
	else
		smtp_client_transaction_rcpt_denied(_rcpt, reply);

	/* call the callback */
	if (rcpt_callback != NULL)
		rcpt_callback(reply, context);
}

void smtp_client_transaction_rcpt_abort(
	struct smtp_client_transaction_rcpt **_rcpt)
{
	struct smtp_client_transaction_rcpt *rcpt = *_rcpt;
	struct smtp_client_transaction *trans = rcpt->trans;

	i_assert(rcpt->queued || rcpt->external_pool);

	i_assert(trans->state <= SMTP_CLIENT_TRANSACTION_STATE_RCPT_TO ||
		 trans->state == SMTP_CLIENT_TRANSACTION_STATE_ABORTED);

	smtp_client_transaction_rcpt_free(_rcpt);
}

static void
smtp_client_transaction_rcpt_fail_reply(
	struct smtp_client_transaction_rcpt **_rcpt,
	const struct smtp_reply *reply)
{
	struct smtp_client_transaction_rcpt *rcpt = *_rcpt;
	struct smtp_client_transaction *trans = rcpt->trans;
	smtp_client_command_callback_t *callback;
	void *context;

	if (rcpt->finished)
		return;
	rcpt->finished = TRUE;

	trans->rcpts_failed++;

	if (rcpt->queued) {
		callback = rcpt->rcpt_callback;
		context = rcpt->context;
	} else {
		callback = rcpt->data_callback;
		context = rcpt->data_context;
	}
	rcpt->rcpt_callback = NULL;
	rcpt->data_callback = NULL;

	struct event_passthrough *e =
		event_create_passthrough(rcpt->event)->
		set_name("smtp_client_transaction_rcpt_finished");
	smtp_reply_add_to_event(reply, e);
	e_debug(e->event(), "Failed");

	if (callback != NULL)
		callback(reply, context);

	smtp_client_transaction_rcpt_free(_rcpt);
}

static void
smtp_client_transaction_rcpt_finished(struct smtp_client_transaction_rcpt *rcpt,
				      const struct smtp_reply *reply)
{
	struct smtp_client_transaction *trans = rcpt->trans;

	i_assert(!rcpt->finished);
	rcpt->finished = TRUE;

	if (smtp_reply_is_success(reply))
		trans->rcpts_succeeded++;
	else
		trans->rcpts_failed++;

	struct event_passthrough *e =
		event_create_passthrough(rcpt->event)->
		set_name("smtp_client_transaction_rcpt_finished");
	smtp_reply_add_to_event(reply, e);
	e_debug(e->event(), "Finished");

	if (rcpt->data_callback != NULL)
		rcpt->data_callback(reply, rcpt->data_context);
	rcpt->data_callback = NULL;
}

#undef smtp_client_transaction_rcpt_set_data_callback
void smtp_client_transaction_rcpt_set_data_callback(
	struct smtp_client_transaction_rcpt *rcpt,
	smtp_client_command_callback_t *callback, void *context)
{
	i_assert(!rcpt->finished);

	rcpt->data_callback = callback;
	rcpt->data_context = context;
}

/*
 * Transaction
 */

static void
smtp_client_transaction_update_event(struct smtp_client_transaction *trans)
{
	event_set_append_log_prefix(trans->event, "transaction: ");
}

static struct event_passthrough *
smtp_client_transaction_result_event(struct smtp_client_transaction *trans,
				     const struct smtp_reply *reply)
{
	struct event_passthrough *e;
	unsigned int rcpts_aborted = trans->rcpts_aborted +
				     trans->rcpts_queue_count;

	e = event_create_passthrough(trans->event)->
		set_name("smtp_client_transaction_finished")->
		add_int("recipients", trans->rcpts_total)->
		add_int("recipients_aborted", rcpts_aborted)->
		add_int("recipients_denied", trans->rcpts_denied)->
		add_int("recipients_failed", trans->rcpts_failed)->
		add_int("recipients_succeeded", trans->rcpts_succeeded);

	smtp_reply_add_to_event(reply, e);
	if (trans->reset)
		e->add_str("is_reset", "yes");
	return e;
}

#undef smtp_client_transaction_create_empty
struct smtp_client_transaction *
smtp_client_transaction_create_empty(
	struct smtp_client_connection *conn,
	enum smtp_client_transaction_flags flags,
	smtp_client_transaction_callback_t *callback, void *context)
{
	struct smtp_client_transaction *trans;
	pool_t pool;

	if (conn->protocol == SMTP_PROTOCOL_LMTP)
		flags |= SMTP_CLIENT_TRANSACTION_FLAG_REPLY_PER_RCPT;

	pool = pool_alloconly_create("smtp transaction", 4096);
	trans = p_new(pool, struct smtp_client_transaction, 1);
	trans->refcount = 1;
	trans->pool = pool;
	trans->flags = flags;
	trans->callback = callback;
	trans->context = context;

	trans->event = event_create(conn->event);
	smtp_client_transaction_update_event(trans);

	trans->conn = conn;
	smtp_client_connection_ref(conn);

	e_debug(trans->event, "Created");

	return trans;
}

#undef smtp_client_transaction_create
struct smtp_client_transaction *
smtp_client_transaction_create(struct smtp_client_connection *conn,
	const struct smtp_address *mail_from,
	const struct smtp_params_mail *mail_params,
	enum smtp_client_transaction_flags flags,
	smtp_client_transaction_callback_t *callback, void *context)
{
	struct smtp_client_transaction *trans;

	trans = smtp_client_transaction_create_empty(conn, flags,
						     callback, context);
	(void)smtp_client_transaction_mail_new(trans, mail_from, mail_params);
	return trans;
}

static void
smtp_client_transaction_finish(struct smtp_client_transaction *trans,
			       const struct smtp_reply *final_reply)
{
	struct smtp_client_connection *conn = trans->conn;

	if (trans->state >= SMTP_CLIENT_TRANSACTION_STATE_FINISHED)
		return;

	timeout_remove(&trans->to_finish);

	struct event_passthrough *e =
		smtp_client_transaction_result_event(trans, final_reply);
	e_debug(e->event(), "Finished");

	io_loop_time_refresh();
	trans->times.finished = ioloop_timeval;

	i_assert(trans->to_send == NULL);

	trans->state = SMTP_CLIENT_TRANSACTION_STATE_FINISHED;
	i_assert(trans->callback != NULL);
	trans->callback(trans->context);

	if (!trans->submitted_data)
		smtp_client_connection_abort_transaction(conn, trans);

	smtp_client_transaction_unref(&trans);
}

void smtp_client_transaction_abort(struct smtp_client_transaction *trans)
{
	struct smtp_client_connection *conn = trans->conn;

	if (trans->failing) {
		e_debug(trans->event, "Abort (already failing)");
		return;
	}

	e_debug(trans->event, "Abort");

	/* clean up */
	i_stream_unref(&trans->data_input);
	timeout_remove(&trans->to_send);
	timeout_remove(&trans->to_finish);

	trans->cmd_last = NULL;

	/* abort any pending commands */
	while (trans->mail_head != NULL) {
		struct smtp_client_transaction_mail *mail = trans->mail_head;

		if (mail->cmd_mail_from != NULL)
			smtp_client_command_abort(&mail->cmd_mail_from);
		smtp_client_transaction_mail_free(&mail);
	}
	while (trans->rcpts_queue_count > 0) {
		struct smtp_client_transaction_rcpt *rcpt =
			trans->rcpts_queue_head;

		if (rcpt->cmd_rcpt_to != NULL)
			smtp_client_command_abort(&rcpt->cmd_rcpt_to);
		smtp_client_transaction_rcpt_free(&rcpt);
	}
	if (trans->cmd_data != NULL)
		smtp_client_command_abort(&trans->cmd_data);
	if (trans->cmd_rset != NULL)
		smtp_client_command_abort(&trans->cmd_rset);
	if (trans->cmd_plug != NULL)
		smtp_client_command_abort(&trans->cmd_plug);
	trans->cmd_data = NULL;
	trans->cmd_rset = NULL;
	trans->cmd_plug = NULL;

	smtp_client_connection_abort_transaction(conn, trans);

	/* abort if not finished */
	if (trans->state < SMTP_CLIENT_TRANSACTION_STATE_FINISHED) {
		struct event_passthrough *e;

		if (trans->failure != NULL) {
			e = smtp_client_transaction_result_event(
				trans, trans->failure);
			e_debug(e->event(), "Failed");
		} else {
			struct smtp_reply failure;

			smtp_reply_init(&failure,
					SMTP_CLIENT_COMMAND_ERROR_ABORTED,
					"Aborted");
			failure.enhanced_code = SMTP_REPLY_ENH_CODE(9, 0, 0);

			e = smtp_client_transaction_result_event(
				trans, &failure);
			e_debug(e->event(), "Aborted");
		}

		trans->state = SMTP_CLIENT_TRANSACTION_STATE_ABORTED;
		i_assert(trans->callback != NULL);
		trans->callback(trans->context);

		smtp_client_transaction_unref(&trans);
	}
}

void smtp_client_transaction_ref(struct smtp_client_transaction *trans)
{
	trans->refcount++;
}

void smtp_client_transaction_unref(struct smtp_client_transaction **_trans)
{
	struct smtp_client_transaction *trans = *_trans;
	struct smtp_client_connection *conn;

	*_trans = NULL;

	if (trans == NULL)
		return;
	conn = trans->conn;

	i_assert(trans->refcount > 0);
	if (--trans->refcount > 0)
		return;

	e_debug(trans->event, "Destroy");

	i_stream_unref(&trans->data_input);
	smtp_client_transaction_abort(trans);

	while (trans->rcpts_count > 0) {
		struct smtp_client_transaction_rcpt *rcpt =
			trans->rcpts_head;
		smtp_client_transaction_rcpt_free(&rcpt);
	}

	i_assert(trans->state >= SMTP_CLIENT_TRANSACTION_STATE_FINISHED);
	event_unref(&trans->event);
	pool_unref(&trans->pool);

	smtp_client_connection_unref(&conn);
}

void smtp_client_transaction_destroy(struct smtp_client_transaction **_trans)
{
	struct smtp_client_transaction *trans = *_trans;
	struct smtp_client_transaction_mail *mail;
	struct smtp_client_transaction_rcpt *rcpt;

	*_trans = NULL;

	if (trans == NULL)
		return;

	smtp_client_transaction_ref(trans);
	smtp_client_transaction_abort(trans);

	/* Make sure this transaction doesn't produce any more callbacks.
	   We cannot fully abort (destroy) these commands, as this may be
	   called from a callback. */
	for (mail = trans->mail_head; mail != NULL; mail = mail->next) {
		if (mail->cmd_mail_from != NULL)
			smtp_client_command_drop_callback(mail->cmd_mail_from);
	}
	for (rcpt = trans->rcpts_queue_head; rcpt != NULL; rcpt = rcpt->next) {
		if (rcpt->cmd_rcpt_to != NULL)
			smtp_client_command_drop_callback(rcpt->cmd_rcpt_to);
	}
	if (trans->cmd_data != NULL)
		smtp_client_command_drop_callback(trans->cmd_data);
	if (trans->cmd_rset != NULL)
		smtp_client_command_drop_callback(trans->cmd_rset);
	if (trans->cmd_plug != NULL)
		smtp_client_command_abort(&trans->cmd_plug);

	/* Free any approved recipients early */
	while (trans->rcpts_count > 0) {
		struct smtp_client_transaction_rcpt *rcpt =
			trans->rcpts_head;
		smtp_client_transaction_rcpt_free(&rcpt);
	}

	if (trans->state < SMTP_CLIENT_TRANSACTION_STATE_FINISHED) {
		struct smtp_client_transaction *trans_tmp = trans;

		trans->state = SMTP_CLIENT_TRANSACTION_STATE_ABORTED;
		smtp_client_transaction_unref(&trans_tmp);
	}

	smtp_client_transaction_unref(&trans);
}

void smtp_client_transaction_fail_reply(struct smtp_client_transaction *trans,
	const struct smtp_reply *reply)
{
	struct smtp_client_transaction_rcpt *rcpt, *rcpt_next;

	if (reply == NULL)
		reply = trans->failure;
	i_assert(reply != NULL);

	trans->failing = TRUE;

	e_debug(trans->event, "Returning failure: %s", smtp_reply_log(reply));

	/* hold a reference to prevent early destruction in a callback */
	smtp_client_transaction_ref(trans);

	trans->cmd_last = NULL;

	timeout_remove(&trans->to_send);

	/* MAIL */
	while (trans->mail_head != NULL) {
		struct smtp_client_transaction_mail *mail = trans->mail_head;

		if (mail->cmd_mail_from != NULL)
			smtp_client_command_abort(&mail->cmd_mail_from);
		smtp_client_transaction_mail_fail_reply(&mail, reply);
	}

	/* RCPT */
	rcpt = trans->rcpts_queue_head;
	while (rcpt != NULL) {
		struct smtp_client_command *cmd = rcpt->cmd_rcpt_to;

		rcpt_next = rcpt->next;

		rcpt->cmd_rcpt_to = NULL;
		if (cmd != NULL)
			smtp_client_command_fail_reply(&cmd, reply);
		else
			smtp_client_transaction_rcpt_fail_reply(&rcpt, reply);

		rcpt = rcpt_next;
	}

	/* DATA / RSET */
	if (!trans->data_provided && !trans->reset) {
		/* none of smtp_client_transaction_send() and
		   smtp_client_transaction_reset() was called so far
		 */
	} else if (trans->cmd_data != NULL) {
		/* the DATA command is still pending; handle the failure by
		   failing the DATA command. */
		smtp_client_command_fail_reply(&trans->cmd_data, reply);
	} else if (trans->cmd_rset != NULL) {
		/* the RSET command is still pending; handle the failure by
		   failing the RSET command. */
		smtp_client_command_fail_reply(&trans->cmd_rset, reply);
	} else {
		i_assert(!trans->reset);

		/* the DATA command was not sent yet; call all DATA callbacks
		   for the recipients that were previously accepted. */
		rcpt = trans->rcpts_data;
		while (rcpt != NULL) {
			rcpt_next = rcpt->next;
			smtp_client_transaction_rcpt_fail_reply(&rcpt, reply);
			rcpt = rcpt_next;
		}
		if (trans->data_callback != NULL)
			trans->data_callback(reply, trans->data_context);
		trans->data_callback = NULL;
	}

	/* plug */
	if (trans->failure == NULL)
		trans->failure = smtp_reply_clone(trans->pool, reply);
	if (trans->cmd_plug != NULL)
		smtp_client_command_abort(&trans->cmd_plug);
	trans->cmd_plug = NULL;

	trans->failing = FALSE;

	if (trans->data_provided || trans->reset) {
		/* abort the transaction only if smtp_client_transaction_send()
		   or  smtp_client_transaction_reset() was called (and if it is
		   not aborted already) */
		smtp_client_transaction_abort(trans);
	}

	/* drop reference held earlier in this function */
	smtp_client_transaction_unref(&trans);
}

void smtp_client_transaction_fail(struct smtp_client_transaction *trans,
	unsigned int status, const char *error)
{
	struct smtp_reply reply;

	smtp_reply_init(&reply, status, error);
	smtp_client_transaction_fail_reply(trans, &reply);
}

void smtp_client_transaction_set_event(struct smtp_client_transaction *trans,
				       struct event *event)
{
	i_assert(trans->conn != NULL);
	event_unref(&trans->event);
	trans->event = event_create(event);
	event_set_forced_debug(trans->event, trans->conn->set.debug);
	smtp_client_transaction_update_event(trans);
}

static void
smtp_client_transaction_timeout(struct smtp_client_transaction *trans)
{
	struct smtp_reply reply;

	smtp_reply_printf(&reply, 451,
		"Remote server not answering "
		"(transaction timed out while %s)",
		smtp_client_transaction_get_state_destription(trans));
	reply.enhanced_code = SMTP_REPLY_ENH_CODE(4, 4, 0);

	smtp_client_transaction_fail_reply(trans, &reply);
}

void smtp_client_transaction_set_timeout(struct smtp_client_transaction *trans,
	unsigned int timeout_msecs)
{
	i_assert(trans->state < SMTP_CLIENT_TRANSACTION_STATE_FINISHED);

	trans->finish_timeout_msecs = timeout_msecs;

	if (trans->data_input != NULL && timeout_msecs > 0) {
		/* adjust timeout if it is already started */
		timeout_remove(&trans->to_finish);
		trans->to_finish = timeout_add(trans->finish_timeout_msecs,
			smtp_client_transaction_timeout, trans);
	}
}

static void
smtp_client_transaction_mail_cb(const struct smtp_reply *reply,
				struct smtp_client_transaction *trans)
{
	struct smtp_client_transaction_mail *mail = trans->mail_head;
	bool success = smtp_reply_is_success(reply);

	e_debug(trans->event, "Got MAIL reply: %s", smtp_reply_log(reply));

	i_assert(mail != NULL);
	i_assert(trans->conn != NULL);

	if (success) {
		if (trans->sender_accepted) {
			smtp_client_transaction_fail(
				trans, SMTP_CLIENT_COMMAND_ERROR_BAD_REPLY,
				"Server accepted more than a single MAIL command.");
			return;
		}
		trans->mail_failure = NULL;
		trans->sender_accepted = TRUE;
	}

	/* plug command line pipeline if no RCPT commands are yet issued */
	if (!trans->immediate && mail->next == NULL &&
	    mail->cmd_mail_from == trans->cmd_last) {
		trans->cmd_plug = trans->cmd_last =
			smtp_client_command_plug(trans->conn, trans->cmd_last);
	}
	mail->cmd_mail_from = NULL;

	if (trans->rcpts_queue_count > 0)
		trans->state = SMTP_CLIENT_TRANSACTION_STATE_RCPT_TO;
	else if (trans->reset)
		trans->state = SMTP_CLIENT_TRANSACTION_STATE_RESET;

	{
		enum smtp_client_transaction_state state;
		struct smtp_client_transaction *tmp_trans = trans;

		smtp_client_transaction_ref(tmp_trans);

		smtp_client_transaction_mail_replied(&mail, reply);

		state = trans->state;
		smtp_client_transaction_unref(&tmp_trans);
		if (state >= SMTP_CLIENT_TRANSACTION_STATE_FINISHED)
			return;
	}

	if (!trans->sender_accepted && trans->mail_head != NULL) {
		/* Update transaction with next MAIL command candidate */
		mail = trans->mail_head;
		event_add_str(trans->event, "mail_from",
			      smtp_address_encode(mail->mail_from));
		smtp_params_mail_add_to_event(&mail->mail_params,
					      trans->event);
	}

	if (!success && !trans->sender_accepted) {
		if (trans->state > SMTP_CLIENT_TRANSACTION_STATE_MAIL_FROM)
			smtp_client_transaction_fail_reply(trans, reply);
		else if (trans->mail_failure == NULL)
			trans->mail_failure = smtp_reply_clone(trans->pool, reply);
	}
}

#undef smtp_client_transaction_add_mail
struct smtp_client_transaction_mail *
smtp_client_transaction_add_mail(struct smtp_client_transaction *trans,
				 const struct smtp_address *mail_from,
				 const struct smtp_params_mail *mail_params,
				 smtp_client_command_callback_t *mail_callback,
				 void *context)
{
	struct smtp_client_transaction_mail *mail;

	e_debug(trans->event, "Add MAIL command");

	i_assert(!trans->data_provided);
	i_assert(!trans->reset);

	i_assert(trans->state < SMTP_CLIENT_TRANSACTION_STATE_RCPT_TO);

	mail = smtp_client_transaction_mail_new(trans, mail_from, mail_params);
	mail->mail_callback = mail_callback;
	mail->context = context;

	smtp_client_transaction_submit(trans, FALSE);

	return mail;
}

static void smtp_client_transaction_connection_ready(
	struct smtp_client_transaction *trans)
{
	if (trans->state != SMTP_CLIENT_TRANSACTION_STATE_PENDING)
		return;

	e_debug(trans->event, "Connecton is ready for transaction");

	trans->state = SMTP_CLIENT_TRANSACTION_STATE_MAIL_FROM;

	smtp_client_transaction_submit_more(trans);
}

#undef smtp_client_transaction_start
void smtp_client_transaction_start(
	struct smtp_client_transaction *trans,
	smtp_client_command_callback_t *mail_callback, void *context)
{
	struct smtp_client_connection *conn = trans->conn;
	struct smtp_client_transaction_mail *mail = trans->mail_head;

	i_assert(trans->state == SMTP_CLIENT_TRANSACTION_STATE_NEW);
	i_assert(trans->conn != NULL);

	i_assert(mail != NULL);
	event_add_str(trans->event, "mail_from",
		      smtp_address_encode(mail->mail_from));
	event_add_str(trans->event, "mail_from_raw",
		      smtp_address_encode_raw(mail->mail_from));
	smtp_params_mail_add_to_event(&mail->mail_params,
				      trans->event);

	struct event_passthrough *e =
		event_create_passthrough(trans->event)->
		set_name("smtp_client_transaction_started");
	e_debug(e->event(), "Start");

	io_loop_time_refresh();
	trans->times.started = ioloop_timeval;

	i_assert(mail->mail_callback == NULL);

	mail->mail_callback = mail_callback;
	mail->context = context;

	trans->state = SMTP_CLIENT_TRANSACTION_STATE_PENDING;

	smtp_client_connection_add_transaction(conn, trans);

	if (trans->immediate &&
	    conn->state == SMTP_CLIENT_CONNECTION_STATE_READY) {
		trans->state = SMTP_CLIENT_TRANSACTION_STATE_MAIL_FROM;

		if (!trans->submitting)
			smtp_client_transaction_submit_more(trans);
	}
}

#undef smtp_client_transaction_start_empty
void smtp_client_transaction_start_empty(
	struct smtp_client_transaction *trans,
	const struct smtp_address *mail_from,
	const struct smtp_params_mail *mail_params,
	smtp_client_command_callback_t *mail_callback, void *context)
{
	i_assert(trans->mail_head == NULL);

	(void)smtp_client_transaction_mail_new(trans, mail_from, mail_params);

	smtp_client_transaction_start(trans, mail_callback, context);
}

static void
smtp_client_transaction_rcpt_cb(const struct smtp_reply *reply,
				struct smtp_client_transaction_rcpt *rcpt)
{
	struct smtp_client_transaction *trans = rcpt->trans;

	i_assert(trans->conn != NULL);

	e_debug(trans->event, "Got RCPT reply: %s", smtp_reply_log(reply));

	/* plug command line pipeline if DATA command is not yet issued */
	if (!trans->immediate && !trans->reset &&
	    rcpt->cmd_rcpt_to == trans->cmd_last && trans->cmd_data == NULL) {
		trans->cmd_plug = trans->cmd_last =
			smtp_client_command_plug(trans->conn, trans->cmd_last);
	}
	rcpt->cmd_rcpt_to = NULL;

	{
		enum smtp_client_transaction_state state;
		struct smtp_client_transaction *tmp_trans = trans;

		smtp_client_transaction_ref(tmp_trans);

		smtp_client_transaction_rcpt_replied(&rcpt, reply);

		state = trans->state;
		smtp_client_transaction_unref(&tmp_trans);
		if (state >= SMTP_CLIENT_TRANSACTION_STATE_FINISHED)
			return;
	}

	smtp_client_transaction_try_complete(trans);
}

#undef smtp_client_transaction_add_rcpt
struct smtp_client_transaction_rcpt *
smtp_client_transaction_add_rcpt(struct smtp_client_transaction *trans,
				 const struct smtp_address *rcpt_to,
				 const struct smtp_params_rcpt *rcpt_params,
				 smtp_client_command_callback_t *rcpt_callback,
				 smtp_client_command_callback_t *data_callback,
				 void *context)
{
	struct smtp_client_transaction_rcpt *rcpt;
	pool_t pool;

	e_debug(trans->event, "Add recipient");

	i_assert(!trans->data_provided);
	i_assert(!trans->reset);

	i_assert(trans->state < SMTP_CLIENT_TRANSACTION_STATE_FINISHED);

	if (trans->mail_head == NULL &&
		trans->state == SMTP_CLIENT_TRANSACTION_STATE_MAIL_FROM)
		trans->state = SMTP_CLIENT_TRANSACTION_STATE_RCPT_TO;

	pool = pool_alloconly_create("smtp transaction rcpt", 512);
	rcpt = smtp_client_transaction_rcpt_new(trans, pool,
						rcpt_to, rcpt_params);
	pool_unref(&pool);

	rcpt->rcpt_callback = rcpt_callback;
	rcpt->context = context;

	rcpt->data_callback = data_callback;
	rcpt->data_context = context;

	smtp_client_transaction_submit(trans, FALSE);

	return rcpt;
}

#undef smtp_client_transaction_add_pool_rcpt
struct smtp_client_transaction_rcpt *
smtp_client_transaction_add_pool_rcpt(
	struct smtp_client_transaction *trans, pool_t pool,
	const struct smtp_address *rcpt_to,
	const struct smtp_params_rcpt *rcpt_params,
	smtp_client_command_callback_t *rcpt_callback, void *context)
{
	struct smtp_client_transaction_rcpt *rcpt;

	e_debug(trans->event, "Add recipient (external pool)");

	i_assert(!trans->data_provided);
	i_assert(!trans->reset);

	i_assert(trans->state < SMTP_CLIENT_TRANSACTION_STATE_FINISHED);

	if (trans->mail_head == NULL &&
		trans->state == SMTP_CLIENT_TRANSACTION_STATE_MAIL_FROM)
		trans->state = SMTP_CLIENT_TRANSACTION_STATE_RCPT_TO;

	rcpt = smtp_client_transaction_rcpt_new(trans, pool,
						rcpt_to, rcpt_params);
	rcpt->rcpt_callback = rcpt_callback;
	rcpt->context = context;
	rcpt->external_pool = TRUE;

	smtp_client_transaction_submit(trans, FALSE);

	return rcpt;
}

static void
smtp_client_transaction_data_cb(const struct smtp_reply *reply,
				struct smtp_client_transaction *trans)
{
	bool reply_per_rcpt = HAS_ALL_BITS(
		trans->flags, SMTP_CLIENT_TRANSACTION_FLAG_REPLY_PER_RCPT);

	i_assert(!trans->reset);

	smtp_client_transaction_ref(trans);

	if (trans->data_input != NULL) {
		event_add_int(trans->event, "data_sent",
			      trans->data_input->v_offset);
		i_stream_unref(&trans->data_input);
	}

	if (reply_per_rcpt &&
	    trans->cmd_data != NULL && /* NULL when failed early */
	    trans->rcpts_data == NULL && trans->rcpts_count > 0) {
		smtp_client_command_set_replies(trans->cmd_data,
						trans->rcpts_count);
	}
	while (trans->rcpts_data != NULL) {
		struct smtp_client_transaction_rcpt *rcpt = trans->rcpts_data;

		trans->rcpts_data = trans->rcpts_data->next;
		smtp_client_transaction_rcpt_finished(rcpt, reply);
		if (HAS_ALL_BITS(trans->flags,
				 SMTP_CLIENT_TRANSACTION_FLAG_REPLY_PER_RCPT))
			break;
	}

	if (reply_per_rcpt && trans->rcpts_count > 1 &&
	    !smtp_reply_is_success(reply) && trans->data_failure == NULL)
		trans->data_failure = smtp_reply_clone(trans->pool, reply);
	if (trans->rcpts_data != NULL) {
		smtp_client_transaction_unref(&trans);
		return;
	}

	trans->cmd_data = NULL;

	if (trans->data_callback != NULL)
		trans->data_callback(reply, trans->data_context);
	trans->data_callback = NULL;

	/* finished */
	smtp_client_transaction_finish(
		trans, (trans->data_failure == NULL ? reply :
			trans->data_failure));

	smtp_client_transaction_unref(&trans);
}

static void
smtp_client_transaction_send_data(struct smtp_client_transaction *trans)
{
	struct smtp_reply failure;

	i_assert(!trans->reset);
	i_assert(trans->data_input != NULL);

	e_debug(trans->event, "Sending data");

	timeout_remove(&trans->to_send);

	i_zero(&failure);
	if (trans->failure != NULL) {
		smtp_client_transaction_fail_reply(trans, trans->failure);
		failure = *trans->failure;
		i_assert(failure.status != 0);
	} else if ((trans->rcpts_count + trans->rcpts_queue_count) == 0) {
		e_debug(trans->event, "No valid recipients");
		if (trans->failure != NULL)
			failure = *trans->failure;
		else {
			smtp_reply_init(&failure, 554, "No valid recipients");
			failure.enhanced_code = SMTP_REPLY_ENH_CODE(5, 5, 0);
		}
		i_assert(failure.status != 0);
	} else {
		i_assert(trans->conn != NULL);

		trans->cmd_data = smtp_client_command_data_submit_after(
			trans->conn, 0, trans->cmd_last, trans->data_input,
			smtp_client_transaction_data_cb, trans);
		trans->submitted_data = TRUE;

		if (trans->cmd_last != NULL)
			smtp_client_command_unlock(trans->cmd_last);

		smtp_client_transaction_try_complete(trans);
	}

	if (trans->cmd_plug != NULL)
		smtp_client_command_abort(&trans->cmd_plug);
	trans->cmd_last = NULL;

	if (failure.status != 0)
		smtp_client_transaction_finish(trans, &failure);
}

#undef smtp_client_transaction_send
void smtp_client_transaction_send(
	struct smtp_client_transaction *trans, struct istream *data_input,
	smtp_client_command_callback_t *data_callback, void *data_context)
{
	i_assert(trans->state < SMTP_CLIENT_TRANSACTION_STATE_FINISHED);
	i_assert(!trans->data_provided);
	i_assert(!trans->reset);

	if (trans->rcpts_queue_count == 0)
		e_debug(trans->event, "Got all RCPT replies");

	e_debug(trans->event, "Send");

	trans->data_provided = TRUE;

	i_assert(trans->data_input == NULL);
	trans->data_input = i_stream_create_crlf(data_input);

	trans->data_callback = data_callback;
	trans->data_context = data_context;

	if (trans->finish_timeout_msecs > 0) {
		i_assert(trans->to_finish == NULL);
		trans->to_finish = timeout_add(trans->finish_timeout_msecs,
			smtp_client_transaction_timeout, trans);
	}

	smtp_client_transaction_submit(trans, TRUE);
}

static void
smtp_client_transaction_rset_cb(const struct smtp_reply *reply,
				struct smtp_client_transaction *trans)
{
	smtp_client_transaction_ref(trans);

	trans->cmd_rset = NULL;

	if (trans->reset_callback != NULL)
		trans->reset_callback(reply, trans->reset_context);
	trans->reset_callback = NULL;

	/* finished */
	smtp_client_transaction_finish(trans, reply);

	smtp_client_transaction_unref(&trans);
}

static void
smtp_client_transaction_send_reset(struct smtp_client_transaction *trans)
{
	struct smtp_reply failure;

	i_assert(trans->reset);

	e_debug(trans->event, "Sending reset");

	timeout_remove(&trans->to_send);

	i_zero(&failure);
	if (trans->failure != NULL) {
		smtp_client_transaction_fail_reply(trans, trans->failure);
		failure = *trans->failure;
		i_assert(failure.status != 0);
	} else {
		i_assert(trans->conn != NULL);

		trans->cmd_rset = smtp_client_command_rset_submit_after(
			trans->conn, 0, trans->cmd_last,
			smtp_client_transaction_rset_cb, trans);

		if (trans->cmd_last != NULL)
			smtp_client_command_unlock(trans->cmd_last);

		smtp_client_transaction_try_complete(trans);
	}

	if (trans->cmd_plug != NULL)
		smtp_client_command_abort(&trans->cmd_plug);
	trans->cmd_last = NULL;

	if (failure.status != 0)
		smtp_client_transaction_finish(trans, &failure);
}

#undef smtp_client_transaction_reset
void smtp_client_transaction_reset(
	struct smtp_client_transaction *trans,
	smtp_client_command_callback_t *reset_callback, void *reset_context)
{
	i_assert(trans->state < SMTP_CLIENT_TRANSACTION_STATE_FINISHED);
	i_assert(!trans->data_provided);
	i_assert(!trans->reset);

	e_debug(trans->event, "Reset");

	trans->reset = TRUE;

	trans->reset_callback = reset_callback;
	trans->reset_context = reset_context;

	if (trans->finish_timeout_msecs > 0) {
		i_assert(trans->to_finish == NULL);
		trans->to_finish = timeout_add(trans->finish_timeout_msecs,
			smtp_client_transaction_timeout, trans);
	}

	smtp_client_transaction_submit(trans, TRUE);
}

static void
smtp_client_transaction_do_submit_more(struct smtp_client_transaction *trans)
{
	timeout_remove(&trans->to_send);

	if (trans->immediate)
		trans->cmd_last = NULL;

	/* Check whether we already failed */
	if (trans->failure == NULL &&
	    trans->state > SMTP_CLIENT_TRANSACTION_STATE_MAIL_FROM)
		trans->failure = trans->mail_failure;
	if (trans->failure != NULL) {
		smtp_client_transaction_fail_reply(trans, trans->failure);
		return;
	}

	i_assert(trans->conn != NULL);

	/* Make sure transaction is started */
	if (trans->state == SMTP_CLIENT_TRANSACTION_STATE_NEW) {
		enum smtp_client_transaction_state state;
		struct smtp_client_transaction *tmp_trans = trans;

		smtp_client_transaction_ref(tmp_trans);
		smtp_client_transaction_start(tmp_trans, NULL, NULL);
		state = trans->state;
		smtp_client_transaction_unref(&tmp_trans);
		if (state >= SMTP_CLIENT_TRANSACTION_STATE_FINISHED)
			return;
	}

	if (trans->state <= SMTP_CLIENT_TRANSACTION_STATE_PENDING)
		return;

	/* MAIL */
	if (trans->mail_send != NULL) {
		e_debug(trans->event, "Sending MAIL command");

		i_assert(trans->state == SMTP_CLIENT_TRANSACTION_STATE_MAIL_FROM);

		if (trans->cmd_last != NULL)
			smtp_client_command_unlock(trans->cmd_last);

		while (trans->mail_send != NULL) {
			struct smtp_client_transaction_mail *mail =
				trans->mail_send;

			trans->mail_send = trans->mail_send->next;
			mail->cmd_mail_from = trans->cmd_last =
				smtp_client_command_mail_submit(trans->conn, 0,
					mail->mail_from, &mail->mail_params,
					smtp_client_transaction_mail_cb, trans);
		}

		if (!trans->immediate)
			smtp_client_command_lock(trans->cmd_last);
	}

	/* RCPT */
	if (trans->rcpts_send != NULL) {
		e_debug(trans->event, "Sending recipients");

		if (trans->cmd_last != NULL)
			smtp_client_command_unlock(trans->cmd_last);

		while (trans->rcpts_send != NULL) {
			struct smtp_client_transaction_rcpt *rcpt =
				trans->rcpts_send;

			trans->rcpts_send = trans->rcpts_send->next;
			rcpt->cmd_rcpt_to = trans->cmd_last =
				smtp_client_command_rcpt_submit_after(
					trans->conn, 0,	trans->cmd_last,
					rcpt->rcpt_to, &rcpt->rcpt_params,
					smtp_client_transaction_rcpt_cb, rcpt);
		}
		if (!trans->immediate)
			smtp_client_command_lock(trans->cmd_last);
	}

	if (trans->cmd_plug != NULL &&
	    (trans->immediate || trans->cmd_last != trans->cmd_plug))
		smtp_client_command_abort(&trans->cmd_plug);

	/* DATA / RSET */
	if (trans->reset) {
		smtp_client_transaction_send_reset(trans);
	} else if (trans->data_input != NULL) {
		smtp_client_transaction_send_data(trans);
	}
}

static void
smtp_client_transaction_submit_more(struct smtp_client_transaction *trans)
{
	smtp_client_transaction_ref(trans);
	trans->submitting = TRUE;
	smtp_client_transaction_do_submit_more(trans);
	trans->submitting = FALSE;
	smtp_client_transaction_unref(&trans);
}

static void
smtp_client_transaction_submit(struct smtp_client_transaction *trans,
			       bool start)
{
	if (trans->failure == NULL && !start &&
	    trans->state <= SMTP_CLIENT_TRANSACTION_STATE_PENDING) {
		/* Cannot submit commands at this time */
		return;
	}

	if (trans->immediate) {
		/* Submit immediately if not failed already: avoid calling
		   failure callbacks directly (which is the first thing
		   smtp_client_transaction_submit_more() would do). */
		if (trans->failure == NULL &&
		    trans->state > SMTP_CLIENT_TRANSACTION_STATE_MAIL_FROM)
			trans->failure = trans->mail_failure;
		if (trans->failure == NULL) {
			smtp_client_transaction_submit_more(trans);
			return;
		}
	}

	if (trans->to_send != NULL) {
		/* Already scheduled command submission */
		return;
	}

	trans->to_send = timeout_add_short(0,
		smtp_client_transaction_submit_more, trans);
}

static void
smtp_client_transaction_try_complete(struct smtp_client_transaction *trans)
{
	i_assert(trans->conn != NULL);

	if (trans->rcpts_queue_count > 0) {
		/* Not all RCPT replies have come in yet */
		e_debug(trans->event,  "RCPT replies are still pending (%u/%u)",
			trans->rcpts_queue_count,
			(trans->rcpts_queue_count + trans->rcpts_count));
		return;
	}
	if (!trans->data_provided && !trans->reset) {
		/* Still waiting for application to issue either
		   smtp_client_transaction_send() or
		   smtp_client_transaction_reset() */
		e_debug(trans->event, "Transaction is not yet complete");
		return;
	}

	if (trans->state == SMTP_CLIENT_TRANSACTION_STATE_RCPT_TO) {
		/* Completed at this instance */
		e_debug(trans->event,
			"Got all RCPT replies and transaction is complete");
	}

	if (trans->reset) {
		/* Entering reset state */
		trans->state = SMTP_CLIENT_TRANSACTION_STATE_RESET;

		if (trans->cmd_rset == NULL)
			return;
	} else {
		/* Entering data state */
		trans->state = SMTP_CLIENT_TRANSACTION_STATE_DATA;

		if (trans->rcpts_count == 0) {
			/* abort transaction if all recipients failed */
			smtp_client_transaction_abort(trans);
			return;
		}

		if (trans->cmd_data == NULL)
			return;

		if (HAS_ALL_BITS(trans->flags,
				 SMTP_CLIENT_TRANSACTION_FLAG_REPLY_PER_RCPT)) {
			smtp_client_command_set_replies(trans->cmd_data,
							trans->rcpts_count);
		}
	}

	/* Got replies for all recipients and submitted our last command;
	   the next transaction can submit its commands now. */
	smtp_client_connection_next_transaction(trans->conn, trans);
}

void smtp_client_transaction_set_immediate(
	struct smtp_client_transaction *trans, bool immediate)
{
	trans->immediate = immediate;
}

void smtp_client_transaction_connection_result(
	struct smtp_client_transaction *trans,
	const struct smtp_reply *reply)
{
	if (!smtp_reply_is_success(reply)) {
		if (trans->state <= SMTP_CLIENT_TRANSACTION_STATE_PENDING) {
			e_debug(trans->event, "Failed to connect: %s",
				smtp_reply_log(reply));
		} else {
			e_debug(trans->event, "Connection lost: %s",
				smtp_reply_log(reply));
		}
		smtp_client_transaction_fail_reply(trans, reply);
		return;
	}

	smtp_client_transaction_connection_ready(trans);
}

void smtp_client_transaction_connection_destroyed(
	struct smtp_client_transaction *trans)
{
	i_assert(trans->failure != NULL);
	smtp_client_connection_unref(&trans->conn);
}

const struct smtp_client_transaction_times *
smtp_client_transaction_get_times(struct smtp_client_transaction *trans)
{
	return &trans->times;
}

enum smtp_client_transaction_state
smtp_client_transaction_get_state(struct smtp_client_transaction *trans)
{
	return trans->state;
}

const char *
smtp_client_transaction_get_state_name(struct smtp_client_transaction *trans)
{
	i_assert(trans->state >= SMTP_CLIENT_TRANSACTION_STATE_NEW &&
		trans->state <= SMTP_CLIENT_TRANSACTION_STATE_ABORTED);
	return smtp_client_transaction_state_names[trans->state];
}

const char *
smtp_client_transaction_get_state_destription(
	struct smtp_client_transaction *trans)
{
	enum smtp_client_connection_state conn_state;

	switch (trans->state) {
	case SMTP_CLIENT_TRANSACTION_STATE_NEW:
		break;
	case SMTP_CLIENT_TRANSACTION_STATE_PENDING:
		i_assert(trans->conn != NULL);
		conn_state = smtp_client_connection_get_state(trans->conn);
		switch (conn_state) {
		case SMTP_CLIENT_CONNECTION_STATE_CONNECTING:
		case SMTP_CLIENT_CONNECTION_STATE_HANDSHAKING:
		case SMTP_CLIENT_CONNECTION_STATE_AUTHENTICATING:
			return smtp_client_connection_state_names[conn_state];
		case SMTP_CLIENT_CONNECTION_STATE_TRANSACTION:
			return "waiting for connection";
		case SMTP_CLIENT_CONNECTION_STATE_DISCONNECTED:
		case SMTP_CLIENT_CONNECTION_STATE_READY:
		default:
			break;
		}
		break;
	case SMTP_CLIENT_TRANSACTION_STATE_MAIL_FROM:
		return "waiting for reply to MAIL FROM";
	case SMTP_CLIENT_TRANSACTION_STATE_RCPT_TO:
		return "waiting for reply to RCPT TO";
	case SMTP_CLIENT_TRANSACTION_STATE_DATA:
		return "waiting for reply to DATA";
	case SMTP_CLIENT_TRANSACTION_STATE_RESET:
		return "waiting for reply to RESET";
	case SMTP_CLIENT_TRANSACTION_STATE_FINISHED:
		return "finished";
	case SMTP_CLIENT_TRANSACTION_STATE_ABORTED:
		return "aborted";
	}
	i_unreached();
}

void smtp_client_transaction_switch_ioloop(
	struct smtp_client_transaction *trans)
{
	if (trans->to_send != NULL)
		trans->to_send = io_loop_move_timeout(&trans->to_send);
	if (trans->to_finish != NULL)
		trans->to_finish = io_loop_move_timeout(&trans->to_finish);
}