From: Stephan Bosch <stephan.bosch@dovecot.fi>
Date: Sun, 7 Oct 2018 19:37:00 +0000 (+0200)
Subject: lib-smtp: server: Create the definitive recipient object right at the reception of... 
X-Git-Tag: 2.3.9~1215
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=ccff7a5301383dd7280022fb51d70637c4295aee;p=thirdparty%2Fdovecot%2Fcore.git

lib-smtp: server: Create the definitive recipient object right at the reception of the RCPT command.

Before, it first allocated stuff on the command pool, which gets freed when the RCPT
command finishes. Allocating the recipient data on its own pool from the start
considerably simplifies the code and prevents very nasty bugs.
---

diff --git a/src/lib-smtp/smtp-server-cmd-rcpt.c b/src/lib-smtp/smtp-server-cmd-rcpt.c
index c383bd08b0..21afee42d5 100644
--- a/src/lib-smtp/smtp-server-cmd-rcpt.c
+++ b/src/lib-smtp/smtp-server-cmd-rcpt.c
@@ -12,6 +12,17 @@
 
 /* RCPT command */
 
+struct smtp_server_cmd_rcpt {
+	struct smtp_server_recipient *rcpt;
+};
+
+static void
+cmd_rcpt_destroy(struct smtp_server_cmd_ctx *cmd ATTR_UNUSED,
+		 struct smtp_server_cmd_rcpt *data)
+{
+	smtp_server_recipient_destroy(&data->rcpt);
+}
+
 static bool
 cmd_rcpt_check_state(struct smtp_server_cmd_ctx *cmd)
 {
@@ -40,8 +51,7 @@ cmd_rcpt_completed(struct smtp_server_cmd_ctx *cmd,
 {
 	struct smtp_server_connection *conn = cmd->conn;
 	struct smtp_server_command *command = cmd->cmd;
-	struct smtp_server_transaction *trans = conn->state.trans;
-	struct smtp_server_recipient *rcpt;
+	struct smtp_server_recipient *rcpt = data->rcpt;
 
 	i_assert(conn->state.pending_rcpt_cmds > 0);
 	conn->state.pending_rcpt_cmds--;
@@ -55,17 +65,8 @@ cmd_rcpt_completed(struct smtp_server_cmd_ctx *cmd,
 	}
 
 	/* success */
-	rcpt = smtp_server_recipient_create(conn, data->path);
-	smtp_params_rcpt_copy(rcpt->pool, &rcpt->params, &data->params);
-	rcpt->context = data->trans_context;
-
+	data->rcpt = NULL; /* clear to prevent destruction */
 	smtp_server_recipient_approved(rcpt);
-
-	if (data->hook_finished != NULL) {
-		data->hook_finished(cmd, trans, rcpt,
-				    array_count(&trans->rcpt_to) - 1);
-		data->hook_finished = NULL;
-	}
 }
 
 static void
@@ -96,6 +97,7 @@ void smtp_server_cmd_rcpt(struct smtp_server_cmd_ctx *cmd,
 	const struct smtp_server_callbacks *callbacks = conn->callbacks;
 	struct smtp_server_command *command = cmd->cmd;
 	struct smtp_server_cmd_rcpt *rcpt_data;
+	struct smtp_server_recipient *rcpt;
 	enum smtp_address_parse_flags path_parse_flags;
 	const char *const *param_extensions = NULL;
 	struct smtp_address *path;
@@ -155,13 +157,16 @@ void smtp_server_cmd_rcpt(struct smtp_server_cmd_ctx *cmd,
 		return;
 	}
 
+	rcpt = smtp_server_recipient_create(conn, path);
+
 	rcpt_data = p_new(cmd->pool, struct smtp_server_cmd_rcpt, 1);
+	rcpt_data->rcpt = rcpt;
 
 	/* [SP Rcpt-parameters] */
 	if (array_is_created(&conn->rcpt_param_extensions))
 		param_extensions = array_idx(&conn->rcpt_param_extensions, 0);
-	if (smtp_params_rcpt_parse(cmd->pool, params, caps, param_extensions,
-				   &rcpt_data->params, &pperror, &error) < 0) {
+	if (smtp_params_rcpt_parse(rcpt->pool, params, caps, param_extensions,
+				   &rcpt->params, &pperror, &error) < 0) {
 		switch (pperror) {
 		case SMTP_PARAM_PARSE_ERROR_BAD_SYNTAX:
 			smtp_server_reply(cmd,
@@ -177,19 +182,18 @@ void smtp_server_cmd_rcpt(struct smtp_server_cmd_ctx *cmd,
 		return;
 	}
 
-	rcpt_data->path = smtp_address_clone(cmd->pool, path);
-
 	smtp_server_command_add_hook(command, SMTP_SERVER_COMMAND_HOOK_NEXT,
 				     cmd_rcpt_recheck, rcpt_data);
 	smtp_server_command_add_hook(command, SMTP_SERVER_COMMAND_HOOK_COMPLETED,
 				     cmd_rcpt_completed, rcpt_data);
-
+	smtp_server_command_add_hook(command, SMTP_SERVER_COMMAND_HOOK_DESTROY,
+				     cmd_rcpt_destroy, rcpt_data);
+	
 	conn->state.pending_rcpt_cmds++;
 
 	smtp_server_command_ref(command);
 	i_assert(callbacks != NULL && callbacks->conn_cmd_rcpt != NULL);
-	if ((ret=callbacks->conn_cmd_rcpt(conn->context,
-		cmd, rcpt_data)) <= 0) {
+	if ((ret=callbacks->conn_cmd_rcpt(conn->context, cmd, rcpt)) <= 0) {
 		i_assert(ret == 0 || smtp_server_command_is_replied(command));
 		/* command is waiting for external event or it failed */
 		smtp_server_command_unref(&command);
diff --git a/src/lib-smtp/smtp-server.h b/src/lib-smtp/smtp-server.h
index ac8c60d8c2..32abb883d1 100644
--- a/src/lib-smtp/smtp-server.h
+++ b/src/lib-smtp/smtp-server.h
@@ -145,19 +145,6 @@ struct smtp_server_cmd_mail {
 	struct timeval timestamp;
 };
 
-struct smtp_server_cmd_rcpt {
-	struct smtp_address *path;
-	struct smtp_params_rcpt params;
-
-	/* called once the recipient is definitively added to the transaction */
-	void (*hook_finished)(struct smtp_server_cmd_ctx *cmd,
-			      struct smtp_server_transaction *trans,
-			      struct smtp_server_recipient *rcpt,
-			      unsigned int index);
-
-	void *trans_context;
-};
-
 struct smtp_server_cmd_auth {
 	const char *sasl_mech;
 	const char *initial_response;
@@ -208,7 +195,7 @@ struct smtp_server_callbacks {
 	/* RCPT */
 	int (*conn_cmd_rcpt)(void *conn_ctx,
 		struct smtp_server_cmd_ctx *cmd,
-		struct smtp_server_cmd_rcpt *data);
+		struct smtp_server_recipient *rcpt);
 	/* RSET */
 	int (*conn_cmd_rset)(void *conn_ctx,
 		struct smtp_server_cmd_ctx *cmd);
diff --git a/src/lib-smtp/test-smtp-payload.c b/src/lib-smtp/test-smtp-payload.c
index 1579b79e3e..a3fe0137ca 100644
--- a/src/lib-smtp/test-smtp-payload.c
+++ b/src/lib-smtp/test-smtp-payload.c
@@ -327,11 +327,11 @@ test_server_conn_trans_free(void *context ATTR_UNUSED,
 static int
 test_server_conn_cmd_rcpt(void *conn_ctx ATTR_UNUSED,
 	struct smtp_server_cmd_ctx *cmd ATTR_UNUSED,
-	struct smtp_server_cmd_rcpt *data)
+	struct smtp_server_recipient *rcpt)
 {
 	if (debug) {
 		i_debug("test server: RCPT TO:%s",
-			smtp_address_encode(data->path));
+			smtp_address_encode(rcpt->path));
 	}
 
 	return 1;
diff --git a/src/lib-smtp/test-smtp-server-errors.c b/src/lib-smtp/test-smtp-server-errors.c
index 309022e972..afd900244e 100644
--- a/src/lib-smtp/test-smtp-server-errors.c
+++ b/src/lib-smtp/test-smtp-server-errors.c
@@ -382,11 +382,11 @@ test_server_hanging_command_payload_trans_free(void *conn_ctx  ATTR_UNUSED,
 static int
 test_server_hanging_command_payload_rcpt(void *conn_ctx ATTR_UNUSED,
 	struct smtp_server_cmd_ctx *cmd ATTR_UNUSED,
-	struct smtp_server_cmd_rcpt *data)
+	struct smtp_server_recipient *rcpt)
 {
 	if (debug) {
 		i_debug("RCPT TO:%s",
-			smtp_address_encode(data->path));
+			smtp_address_encode(rcpt->path));
 	}
 
 	return 1;
@@ -526,7 +526,7 @@ test_server_bad_command_helo(void *conn_ctx ATTR_UNUSED,
 static int
 test_server_bad_command_rcpt(void *conn_ctx ATTR_UNUSED,
 	struct smtp_server_cmd_ctx *cmd ATTR_UNUSED,
-	struct smtp_server_cmd_rcpt *data ATTR_UNUSED)
+	struct smtp_server_recipient *rcpt ATTR_UNUSED)
 {
 	return 1;
 }
@@ -620,7 +620,7 @@ test_server_long_command_helo(void *conn_ctx ATTR_UNUSED,
 static int
 test_server_long_command_rcpt(void *conn_ctx ATTR_UNUSED,
 	struct smtp_server_cmd_ctx *cmd ATTR_UNUSED,
-	struct smtp_server_cmd_rcpt *data ATTR_UNUSED)
+	struct smtp_server_recipient *rcpt ATTR_UNUSED)
 {
 	return 1;
 }
@@ -718,11 +718,11 @@ test_server_big_data_trans_free(void *conn_ctx  ATTR_UNUSED,
 static int
 test_server_big_data_rcpt(void *conn_ctx ATTR_UNUSED,
 	struct smtp_server_cmd_ctx *cmd ATTR_UNUSED,
-	struct smtp_server_cmd_rcpt *data)
+	struct smtp_server_recipient *rcpt)
 {
 	if (debug) {
 		i_debug("RCPT TO:%s",
-			smtp_address_encode(data->path));
+			smtp_address_encode(rcpt->path));
 	}
 	return 1;
 }
@@ -869,7 +869,7 @@ test_server_bad_ehlo_helo(void *conn_ctx ATTR_UNUSED,
 static int
 test_server_bad_ehlo_rcpt(void *conn_ctx ATTR_UNUSED,
 	struct smtp_server_cmd_ctx *cmd ATTR_UNUSED,
-	struct smtp_server_cmd_rcpt *data ATTR_UNUSED)
+	struct smtp_server_recipient *rcpt ATTR_UNUSED)
 {
 	return 1;
 }
@@ -1048,7 +1048,7 @@ test_server_bad_mail_disconnect(void *context ATTR_UNUSED, const char *reason)
 static int
 test_server_bad_mail_rcpt(void *conn_ctx ATTR_UNUSED,
 	struct smtp_server_cmd_ctx *cmd ATTR_UNUSED,
-	struct smtp_server_cmd_rcpt *data ATTR_UNUSED)
+	struct smtp_server_recipient *rcpt ATTR_UNUSED)
 {
 	test_assert(FALSE);
 	return 1;
@@ -1228,7 +1228,7 @@ test_server_bad_rcpt_disconnect(void *context ATTR_UNUSED, const char *reason)
 static int
 test_server_bad_rcpt_rcpt(void *conn_ctx ATTR_UNUSED,
 	struct smtp_server_cmd_ctx *cmd ATTR_UNUSED,
-	struct smtp_server_cmd_rcpt *data ATTR_UNUSED)
+	struct smtp_server_recipient *rcpt ATTR_UNUSED)
 {
 	return 1;
 }
@@ -1415,7 +1415,7 @@ test_server_mail_workarounds_disconnect(void *context ATTR_UNUSED,
 static int
 test_server_mail_workarounds_rcpt(void *conn_ctx ATTR_UNUSED,
 	struct smtp_server_cmd_ctx *cmd ATTR_UNUSED,
-	struct smtp_server_cmd_rcpt *data ATTR_UNUSED)
+	struct smtp_server_recipient *rcpt ATTR_UNUSED)
 {
 	test_assert(FALSE);
 	return 1;
@@ -1609,7 +1609,7 @@ test_server_rcpt_workarounds_disconnect(void *context ATTR_UNUSED,
 static int
 test_server_rcpt_workarounds_rcpt(void *conn_ctx ATTR_UNUSED,
 	struct smtp_server_cmd_ctx *cmd ATTR_UNUSED,
-	struct smtp_server_cmd_rcpt *data ATTR_UNUSED)
+	struct smtp_server_recipient *rcpt ATTR_UNUSED)
 {
 	return 1;
 }
@@ -1708,11 +1708,11 @@ test_server_too_many_recipients_trans_free(void *conn_ctx  ATTR_UNUSED,
 static int
 test_server_too_many_recipients_rcpt(void *conn_ctx ATTR_UNUSED,
 	struct smtp_server_cmd_ctx *cmd ATTR_UNUSED,
-	struct smtp_server_cmd_rcpt *data)
+	struct smtp_server_recipient *rcpt)
 {
 	if (debug) {
 		i_debug("RCPT TO:%s",
-			smtp_address_encode(data->path));
+			smtp_address_encode(rcpt->path));
 	}
 	return 1;
 }
@@ -1785,7 +1785,7 @@ static void test_client_data_no_mail(unsigned int index)
 static int
 test_server_data_no_mail_rcpt(void *conn_ctx ATTR_UNUSED,
 	struct smtp_server_cmd_ctx *cmd ATTR_UNUSED,
-	struct smtp_server_cmd_rcpt *data ATTR_UNUSED)
+	struct smtp_server_recipient *rcpt ATTR_UNUSED)
 {
 	/* not supposed to get here */
 	i_assert(FALSE);
@@ -1877,7 +1877,7 @@ test_server_data_no_rcpt_trans_free(void *conn_ctx  ATTR_UNUSED,
 static int
 test_server_data_no_rcpt_rcpt(void *conn_ctx ATTR_UNUSED,
 	struct smtp_server_cmd_ctx *cmd ATTR_UNUSED,
-	struct smtp_server_cmd_rcpt *data ATTR_UNUSED)
+	struct smtp_server_recipient *rcpt ATTR_UNUSED)
 {
 	/* not supposed to get here */
 	i_assert(FALSE);
@@ -1962,11 +1962,11 @@ test_server_data_binarymime_trans_free(void *conn_ctx  ATTR_UNUSED,
 static int
 test_server_data_binarymime_rcpt(void *conn_ctx ATTR_UNUSED,
 	struct smtp_server_cmd_ctx *cmd ATTR_UNUSED,
-	struct smtp_server_cmd_rcpt *data)
+	struct smtp_server_recipient *rcpt)
 {
 	if (debug) {
 		i_debug("RCPT TO:%s",
-			smtp_address_encode(data->path));
+			smtp_address_encode(rcpt->path));
 	}
 	return 1;
 }
diff --git a/src/lmtp/commands.c b/src/lmtp/commands.c
index 51625a6d9c..95c4145067 100644
--- a/src/lmtp/commands.c
+++ b/src/lmtp/commands.c
@@ -44,7 +44,7 @@ int cmd_mail(void *conn_ctx,
  */
 
 int cmd_rcpt(void *conn_ctx, struct smtp_server_cmd_ctx *cmd,
-	     struct smtp_server_cmd_rcpt *data)
+	     struct smtp_server_recipient *rcpt)
 {
 	struct client *client = (struct client *)conn_ctx;
 	const char *username, *detail;
@@ -53,17 +53,17 @@ int cmd_rcpt(void *conn_ctx, struct smtp_server_cmd_ctx *cmd,
 
 	smtp_address_detail_parse_temp(
 		client->unexpanded_lda_set->recipient_delimiter,
-		data->path, &username, &delim, &detail);
+		rcpt->path, &username, &delim, &detail);
 	if (client->lmtp_set->lmtp_proxy) {
 		/* proxied? */
-		if ((ret=lmtp_proxy_rcpt(client, cmd, data,
+		if ((ret=lmtp_proxy_rcpt(client, cmd, rcpt,
 					 username, detail, delim)) != 0)
 			return (ret < 0 ? -1 : 0);
 		/* no */
 	}
 
 	/* local delivery */
-	return lmtp_local_rcpt(client, cmd, data, username, detail);
+	return lmtp_local_rcpt(client, cmd, rcpt, username, detail);
 }
 
 /*
diff --git a/src/lmtp/commands.h b/src/lmtp/commands.h
index f7a2aa8ad4..4aaa51c811 100644
--- a/src/lmtp/commands.h
+++ b/src/lmtp/commands.h
@@ -8,7 +8,7 @@ struct smtp_server_cmd_helo;
 int cmd_mail(void *conn_ctx, struct smtp_server_cmd_ctx *cmd,
 	     struct smtp_server_cmd_mail *data);
 int cmd_rcpt(void *conn_ctx, struct smtp_server_cmd_ctx *cmd,
-	     struct smtp_server_cmd_rcpt *data);
+	     struct smtp_server_recipient *rcpt);
 int cmd_data_continue(void *conn_ctx, struct smtp_server_cmd_ctx *cmd,
 		      struct smtp_server_transaction *trans);
 int cmd_data_begin(void *conn_ctx, struct smtp_server_cmd_ctx *cmd ATTR_UNUSED,
diff --git a/src/lmtp/lmtp-common.c b/src/lmtp/lmtp-common.c
index f740600a24..58678e56c6 100644
--- a/src/lmtp/lmtp-common.c
+++ b/src/lmtp/lmtp-common.c
@@ -8,23 +8,18 @@ void lmtp_recipient_init(struct lmtp_recipient *lrcpt,
 			 struct client *client,
 			 enum lmtp_recipient_type type,
 			 struct smtp_server_cmd_ctx *cmd,
-			 struct smtp_server_cmd_rcpt *data)
+			 struct smtp_server_recipient *rcpt)
 {
 	lrcpt->client = client;
 	lrcpt->type = type;
 	lrcpt->rcpt_cmd = cmd;
-	lrcpt->path = data->path;
+	lrcpt->rcpt = rcpt;
+	lrcpt->path = rcpt->path;
 }
 
-void lmtp_recipient_finish(struct lmtp_recipient *lrcpt,
-			   struct smtp_server_recipient *rcpt,
-			   unsigned int index)
+void lmtp_recipient_finish(struct lmtp_recipient *lrcpt)
 {
-	rcpt->context = lrcpt;
-
-	lrcpt->path = rcpt->path;
-	lrcpt->rcpt = rcpt;
-	lrcpt->index = index;
+	lrcpt->index = lrcpt->rcpt->index;
 	lrcpt->rcpt_cmd = NULL;
 }
 
diff --git a/src/lmtp/lmtp-common.h b/src/lmtp/lmtp-common.h
index a2dc1f8628..d81f3dc121 100644
--- a/src/lmtp/lmtp-common.h
+++ b/src/lmtp/lmtp-common.h
@@ -26,11 +26,9 @@ void lmtp_recipient_init(struct lmtp_recipient *lrcpt,
 			 struct client *client,
 			 enum lmtp_recipient_type type,
 			 struct smtp_server_cmd_ctx *cmd,
-			 struct smtp_server_cmd_rcpt *data);
+			 struct smtp_server_recipient *rcpt);
 
-void lmtp_recipient_finish(struct lmtp_recipient *lrcpt,
-			   struct smtp_server_recipient *rcpt,
-			   unsigned int index);
+void lmtp_recipient_finish(struct lmtp_recipient *lrcpt);
 
 struct lmtp_recipient *
 lmtp_recipient_find_duplicate(struct lmtp_recipient *lrcpt,
diff --git a/src/lmtp/lmtp-local.c b/src/lmtp/lmtp-local.c
index 87bcd43f1b..27168ffc7d 100644
--- a/src/lmtp/lmtp-local.c
+++ b/src/lmtp/lmtp-local.c
@@ -252,13 +252,10 @@ lmtp_local_rcpt_check_quota(struct lmtp_local_recipient *llrcpt)
 	return ret;
 }
 
-static void lmtp_local_rcpt_finished(
-	struct smtp_server_cmd_ctx *cmd,
-	struct smtp_server_transaction *trans,
-	struct smtp_server_recipient *rcpt,
-	unsigned int index)
+static void
+lmtp_local_rcpt_approved(struct smtp_server_recipient *rcpt,
+			 struct lmtp_local_recipient *llrcpt)
 {
-	struct lmtp_local_recipient *llrcpt = rcpt->context;
 	struct client *client = llrcpt->rcpt.client;
 
 	smtp_server_command_remove_hook(
@@ -266,17 +263,11 @@ static void lmtp_local_rcpt_finished(
 		SMTP_SERVER_COMMAND_HOOK_DESTROY,
 		lmtp_local_rcpt_cmd_destroy);
 
-	if (!smtp_server_command_replied_success(cmd->cmd)) {
-		/* failed in RCPT command; clean up early */
-		lmtp_local_rcpt_deinit(llrcpt);
-		return;
-	}
-
-	lmtp_recipient_finish(&llrcpt->rcpt, rcpt, index);
+	lmtp_recipient_finish(&llrcpt->rcpt);
 
 	/* resolve duplicate recipient */
 	llrcpt->duplicate = (struct lmtp_local_recipient *)
-		lmtp_recipient_find_duplicate(&llrcpt->rcpt, trans);
+		lmtp_recipient_find_duplicate(&llrcpt->rcpt, rcpt->trans);
 	i_assert(llrcpt->duplicate == NULL ||
 		 llrcpt->duplicate->duplicate == NULL);
 
@@ -332,11 +323,11 @@ lmtp_local_rcpt_anvil_cb(const char *reply, void *context)
 
 int lmtp_local_rcpt(struct client *client,
 	struct smtp_server_cmd_ctx *cmd,
-	struct smtp_server_cmd_rcpt *data,
+	struct smtp_server_recipient *rcpt,
 	const char *username, const char *detail)
 {
 	struct smtp_server_connection *conn = cmd->conn;
-	const struct smtp_address *address = data->path;
+	const struct smtp_address *address = rcpt->path;
 	struct smtp_server_transaction *trans;
 	struct lmtp_local_recipient *llrcpt;
 	struct mail_storage_service_input input;
@@ -391,7 +382,7 @@ int lmtp_local_rcpt(struct client *client,
 
 	llrcpt = i_new(struct lmtp_local_recipient, 1);
 	lmtp_recipient_init(&llrcpt->rcpt, client,
-			    LMTP_RECIPIENT_TYPE_LOCAL, cmd, data);
+			    LMTP_RECIPIENT_TYPE_LOCAL, cmd, rcpt);
 
 	llrcpt->detail = i_strdup(detail);
 	llrcpt->service_user = service_user;
@@ -400,8 +391,10 @@ int lmtp_local_rcpt(struct client *client,
 	smtp_server_command_add_hook(cmd->cmd, SMTP_SERVER_COMMAND_HOOK_DESTROY,
 				     lmtp_local_rcpt_cmd_destroy, llrcpt);
 
-	data->trans_context = llrcpt;
-	data->hook_finished = lmtp_local_rcpt_finished;
+	smtp_server_recipient_add_hook(
+		rcpt, SMTP_SERVER_RECIPIENT_HOOK_APPROVED,
+		lmtp_local_rcpt_approved, llrcpt);
+	rcpt->context = llrcpt;
 
 	if (client->lmtp_set->lmtp_user_concurrency_limit == 0) {
 		(void)lmtp_local_rcpt_anvil_finish(llrcpt);
diff --git a/src/lmtp/lmtp-local.h b/src/lmtp/lmtp-local.h
index edd6156f7f..11331f9511 100644
--- a/src/lmtp/lmtp-local.h
+++ b/src/lmtp/lmtp-local.h
@@ -13,7 +13,7 @@ void lmtp_local_deinit(struct lmtp_local **_local);
 
 int lmtp_local_rcpt(struct client *client,
 		    struct smtp_server_cmd_ctx *cmd,
-		    struct smtp_server_cmd_rcpt *data,
+		    struct smtp_server_recipient *rcpt,
 		    const char *username, const char *detail);
 
 void lmtp_local_add_headers(struct lmtp_local *local,
diff --git a/src/lmtp/lmtp-proxy.c b/src/lmtp/lmtp-proxy.c
index fe9e1a019e..6550db1e48 100644
--- a/src/lmtp/lmtp-proxy.c
+++ b/src/lmtp/lmtp-proxy.c
@@ -444,12 +444,9 @@ lmtp_proxy_rcpt_cmd_destroy(struct smtp_server_cmd_ctx *cmd ATTR_UNUSED,
 }
 
 static void
-lmtp_proxy_rcpt_finished(struct smtp_server_cmd_ctx *cmd,
-			 struct smtp_server_transaction *trans ATTR_UNUSED,
-			 struct smtp_server_recipient *rcpt,
-			 unsigned int index)
+lmtp_proxy_rcpt_approved(struct smtp_server_recipient *rcpt ATTR_UNUSED,
+			 struct lmtp_proxy_recipient *lprcpt)
 {
-	struct lmtp_proxy_recipient *lprcpt = rcpt->context;
 	struct client *client = lprcpt->rcpt.client;
 
 	if (lprcpt->rcpt.rcpt_cmd != NULL) {
@@ -459,13 +456,7 @@ lmtp_proxy_rcpt_finished(struct smtp_server_cmd_ctx *cmd,
 			lmtp_proxy_rcpt_cmd_destroy);
 	}
 
-	if (!smtp_server_command_replied_success(cmd->cmd)) {
-		/* failed in RCPT command; clean up early */
-		lmtp_proxy_recipient_deinit(lprcpt);
-		return;
-	}
-
-	lmtp_recipient_finish(&lprcpt->rcpt, rcpt, index);
+	lmtp_recipient_finish(&lprcpt->rcpt);
 
 	/* add to local recipients */
 	array_append(&client->proxy->rcpt_to, &lprcpt, 1);
@@ -495,7 +486,7 @@ lmtp_proxy_rcpt_cb(const struct smtp_reply *proxy_reply,
 
 int lmtp_proxy_rcpt(struct client *client,
 		    struct smtp_server_cmd_ctx *cmd,
-		    struct smtp_server_cmd_rcpt *data,
+		    struct smtp_server_recipient *rcpt,
 		    const char *username, const char *detail,
 		    char delim)
 {
@@ -504,7 +495,7 @@ int lmtp_proxy_rcpt(struct client *client,
 	struct lmtp_proxy_connection *conn;
 	struct lmtp_proxy_recipient *lprcpt;
 	struct smtp_server_transaction *trans;
-	struct smtp_address *address = data->path;
+	struct smtp_address *address = rcpt->path;
 	struct auth_user_info info;
 	struct mail_storage_service_input input;
 	const char *const *fields, *errstr, *orig_username = username;
@@ -596,25 +587,25 @@ int lmtp_proxy_rcpt(struct client *client,
 	if (client->proxy == NULL)
 		client->proxy = lmtp_proxy_init(client, trans);
 
-	data->path = smtp_address_clone(cmd->pool, address);
-
 	conn = lmtp_proxy_get_connection(client->proxy, &set);
 	pool_unref(&auth_pool);
 
 	lprcpt = i_new(struct lmtp_proxy_recipient, 1);
 	lmtp_recipient_init(&lprcpt->rcpt, client,
-			    LMTP_RECIPIENT_TYPE_PROXY, cmd, data);
-
+			    LMTP_RECIPIENT_TYPE_PROXY, cmd, rcpt);
+	lprcpt->rcpt.path = smtp_address_clone(rcpt->pool, address);
 	lprcpt->conn = conn;
 
 	smtp_server_command_add_hook(cmd->cmd, SMTP_SERVER_COMMAND_HOOK_DESTROY,
 				     lmtp_proxy_rcpt_cmd_destroy, lprcpt);
 
-	data->trans_context = lprcpt;
-	data->hook_finished = lmtp_proxy_rcpt_finished;
+	smtp_server_recipient_add_hook(
+		rcpt, SMTP_SERVER_RECIPIENT_HOOK_APPROVED,
+		lmtp_proxy_rcpt_approved, lprcpt);
+	rcpt->context = lprcpt;
 
 	smtp_client_transaction_add_rcpt(conn->lmtp_trans,
-		address, &data->params,
+		address, &rcpt->params,
 		lmtp_proxy_rcpt_cb, lmtp_proxy_data_cb, lprcpt);
 	return 1;
 }
@@ -631,7 +622,7 @@ lmtp_proxy_data_cb(const struct smtp_reply *proxy_reply,
 	struct lmtp_proxy *proxy = conn->proxy;
 	struct smtp_server_cmd_ctx *cmd = proxy->pending_data_cmd;
 	struct smtp_server_transaction *trans = proxy->trans;
-	struct smtp_address *address = lprcpt->rcpt.rcpt->path;
+	struct smtp_address *address = lprcpt->rcpt.path;
 	const struct smtp_client_transaction_times *times =
 		smtp_client_transaction_get_times(conn->lmtp_trans);
 	unsigned int rcpt_index = lprcpt->rcpt.index;
diff --git a/src/lmtp/lmtp-proxy.h b/src/lmtp/lmtp-proxy.h
index ee6fc2e4a5..bd475eac93 100644
--- a/src/lmtp/lmtp-proxy.h
+++ b/src/lmtp/lmtp-proxy.h
@@ -18,7 +18,7 @@ void lmtp_proxy_deinit(struct lmtp_proxy **proxy);
 
 int lmtp_proxy_rcpt(struct client *client,
 		    struct smtp_server_cmd_ctx *cmd,
-		    struct smtp_server_cmd_rcpt *data,
+		    struct smtp_server_recipient *rcpt,
 		    const char *username, const char *detail, char delim);
 
 void lmtp_proxy_data(struct client *client,
diff --git a/src/submission/submission-backend-relay.c b/src/submission/submission-backend-relay.c
index 734df10e29..48a6d60e71 100644
--- a/src/submission/submission-backend-relay.c
+++ b/src/submission/submission-backend-relay.c
@@ -427,7 +427,7 @@ struct relay_cmd_rcpt_context {
 	struct submission_backend_relay *backend;
 
 	struct smtp_server_cmd_ctx *cmd;
-	struct smtp_server_cmd_rcpt *data;
+	struct smtp_server_recipient *rcpt;
 
 	struct smtp_client_transaction_rcpt *relay_rcpt;
 };
@@ -476,7 +476,7 @@ relay_cmd_rcpt_callback(const struct smtp_reply *relay_reply,
 static int
 backend_relay_cmd_rcpt(struct submission_backend *_backend,
 		       struct smtp_server_cmd_ctx *cmd,
-		       struct smtp_server_cmd_rcpt *data)
+		       struct smtp_server_recipient *rcpt)
 {
 	struct submission_backend_relay *backend =
 		(struct submission_backend_relay *)_backend;
@@ -486,7 +486,7 @@ backend_relay_cmd_rcpt(struct submission_backend *_backend,
 	rcpt_cmd = p_new(cmd->pool, struct relay_cmd_rcpt_context, 1);
 	rcpt_cmd->backend = backend;
 	rcpt_cmd->cmd = cmd;
-	rcpt_cmd->data = data;
+	rcpt_cmd->rcpt = rcpt;
 
 	smtp_server_command_add_hook(cmd->cmd, SMTP_SERVER_COMMAND_HOOK_REPLIED,
 				     relay_cmd_rcpt_replied, rcpt_cmd);
@@ -496,7 +496,7 @@ backend_relay_cmd_rcpt(struct submission_backend *_backend,
 			backend->conn, backend_relay_trans_finished, backend);
 	}
 	rcpt_cmd->relay_rcpt = smtp_client_transaction_add_rcpt(
-		backend->trans, data->path,  &data->params,
+		backend->trans, rcpt->path,  &rcpt->params,
 		relay_cmd_rcpt_callback, relay_cmd_rcpt_data_callback,
 		rcpt_cmd);
 	return 0;
diff --git a/src/submission/submission-backend.c b/src/submission/submission-backend.c
index 66dfc81ca0..0878428b51 100644
--- a/src/submission/submission-backend.c
+++ b/src/submission/submission-backend.c
@@ -177,14 +177,14 @@ int submission_backend_cmd_mail(struct submission_backend *backend,
 
 int submission_backend_cmd_rcpt(struct submission_backend *backend,
 				struct smtp_server_cmd_ctx *cmd,
-				struct smtp_server_cmd_rcpt *data)
+				struct smtp_server_recipient *rcpt)
 {
 	if (backend->v.cmd_rcpt == NULL) {
 		/* backend is not interested, respond right away */
 		return 1;
 	}
 
-	return backend->v.cmd_rcpt(backend, cmd, data);
+	return backend->v.cmd_rcpt(backend, cmd, rcpt);
 }
 
 int submission_backend_cmd_rset(struct submission_backend *backend,
diff --git a/src/submission/submission-backend.h b/src/submission/submission-backend.h
index 92f58fa87c..8e2bc315eb 100644
--- a/src/submission/submission-backend.h
+++ b/src/submission/submission-backend.h
@@ -27,7 +27,7 @@ struct submission_backend_vfuncs {
 			struct smtp_server_cmd_mail *data);
 	int (*cmd_rcpt)(struct submission_backend *backend,
 			struct smtp_server_cmd_ctx *cmd,
-			struct smtp_server_cmd_rcpt *data);
+			struct smtp_server_recipient *rcpt);
 	int (*cmd_rset)(struct submission_backend *backend,
 			struct smtp_server_cmd_ctx *cmd);
 	int (*cmd_data)(struct submission_backend *backend,
@@ -92,7 +92,7 @@ int submission_backend_cmd_mail(struct submission_backend *backend,
 				struct smtp_server_cmd_mail *data);
 int submission_backend_cmd_rcpt(struct submission_backend *backend,
 				struct smtp_server_cmd_ctx *cmd,
-				struct smtp_server_cmd_rcpt *data);
+				struct smtp_server_recipient *rcpt);
 int submission_backend_cmd_rset(struct submission_backend *backend,
 				struct smtp_server_cmd_ctx *cmd);
 int submission_backends_cmd_data(struct client *client,
diff --git a/src/submission/submission-client.h b/src/submission/submission-client.h
index 4c7a81b2c1..2968043549 100644
--- a/src/submission/submission-client.h
+++ b/src/submission/submission-client.h
@@ -39,7 +39,7 @@ struct submission_client_vfuncs {
 	int (*cmd_rcpt)(struct client *client,
 			struct submission_recipient *srcpt,
 			struct smtp_server_cmd_ctx *cmd,
-			struct smtp_server_cmd_rcpt *data);
+			struct smtp_server_recipient *rcpt);
 	int (*cmd_rset)(struct client *client, struct smtp_server_cmd_ctx *cmd);
 	int (*cmd_data)(struct client *client,
 			struct smtp_server_cmd_ctx *cmd,
diff --git a/src/submission/submission-commands.c b/src/submission/submission-commands.c
index 11291cc89e..f44a99223c 100644
--- a/src/submission/submission-commands.c
+++ b/src/submission/submission-commands.c
@@ -152,41 +152,35 @@ cmd_rcpt_destroy(struct smtp_server_cmd_ctx *cmd ATTR_UNUSED,
 }
 
 static void
-submission_rcpt_finished(struct smtp_server_cmd_ctx *cmd,
-			 struct smtp_server_transaction *trans ATTR_UNUSED,
-			 struct smtp_server_recipient *rcpt,
-			 unsigned int index)
+cmd_rcpt_approved(struct smtp_server_recipient *rcpt,
+		  struct submission_recipient *srcpt)
 {
-	struct submission_recipient *srcpt = rcpt->context;
-
-	smtp_server_command_remove_hook(cmd->cmd,
-					SMTP_SERVER_COMMAND_HOOK_DESTROY,
-					cmd_rcpt_destroy);
-
-	submission_recipient_finished(srcpt, rcpt, index);
+	submission_recipient_finished(srcpt, rcpt, rcpt->index);
 }
 
 int cmd_rcpt(void *conn_ctx, struct smtp_server_cmd_ctx *cmd,
-	     struct smtp_server_cmd_rcpt *data)
+	     struct smtp_server_recipient *rcpt)
 {
 	struct client *client = conn_ctx;
 	struct submission_recipient *srcpt;
 
-	srcpt = submission_recipient_create(client, data->path);
+	srcpt = submission_recipient_create(client, rcpt->path);
 
 	smtp_server_command_add_hook(cmd->cmd, SMTP_SERVER_COMMAND_HOOK_DESTROY,
 				     cmd_rcpt_destroy, srcpt);
 
-	data->trans_context = srcpt;
-	data->hook_finished = submission_rcpt_finished;
+	smtp_server_recipient_add_hook(
+		rcpt, SMTP_SERVER_RECIPIENT_HOOK_APPROVED,
+		cmd_rcpt_approved, srcpt);
+	rcpt->context = srcpt;
 
-	return client->v.cmd_rcpt(client, srcpt, cmd, data);
+	return client->v.cmd_rcpt(client, srcpt, cmd, rcpt);
 }
 
 int client_default_cmd_rcpt(struct client *client ATTR_UNUSED,
 			    struct submission_recipient *srcpt,
 			    struct smtp_server_cmd_ctx *cmd,
-			    struct smtp_server_cmd_rcpt *data)
+			    struct smtp_server_recipient *rcpt)
 {
 	struct smtp_server_transaction *trans;
 
@@ -194,7 +188,7 @@ int client_default_cmd_rcpt(struct client *client ATTR_UNUSED,
 	if (trans != NULL)
 		submission_backend_trans_start(srcpt->backend, trans);
 
-	return submission_backend_cmd_rcpt(srcpt->backend, cmd, data);
+	return submission_backend_cmd_rcpt(srcpt->backend, cmd, rcpt);
 }
 
 /*
diff --git a/src/submission/submission-commands.h b/src/submission/submission-commands.h
index c89f572870..875ca3e2a9 100644
--- a/src/submission/submission-commands.h
+++ b/src/submission/submission-commands.h
@@ -31,12 +31,12 @@ int client_default_cmd_mail(struct client *client,
  */
 
 int cmd_rcpt(void *conn_ctx, struct smtp_server_cmd_ctx *cmd,
-	     struct smtp_server_cmd_rcpt *data);
+	     struct smtp_server_recipient *rcpt);
 
 int client_default_cmd_rcpt(struct client *client ATTR_UNUSED,
 			    struct submission_recipient *srcpt,
 			    struct smtp_server_cmd_ctx *cmd,
-			    struct smtp_server_cmd_rcpt *data);
+			    struct smtp_server_recipient *rcpt);
 
 /*
  * RSET command