1 files changed, 439 insertions, 0 deletions

diff --git a/src/lmtp/lmtp-client.c b/src/lmtp/lmtp-client.c
new file mode 100644
index 0000000..2757c80
--- /dev/null
+++ b/src/lmtp/lmtp-client.c
@@ -0,0 +1,439 @@
+/* Copyright (c) 2009-2018 Dovecot authors, see the included COPYING file */
+
+#include "lmtp-common.h"
+#include "base64.h"
+#include "str.h"
+#include "llist.h"
+#include "iostream.h"
+#include "istream.h"
+#include "ostream.h"
+#include "hostpid.h"
+#include "process-title.h"
+#include "var-expand.h"
+#include "module-dir.h"
+#include "master-service-ssl.h"
+#include "master-service-settings.h"
+#include "iostream-ssl.h"
+#include "mail-namespace.h"
+#include "mail-storage.h"
+#include "mail-storage-service.h"
+#include "raw-storage.h"
+#include "lda-settings.h"
+#include "lmtp-local.h"
+#include "lmtp-proxy.h"
+#include "lmtp-commands.h"
+
+#include <unistd.h>
+
+#define CLIENT_IDLE_TIMEOUT_MSECS (1000*60*5)
+
+static const struct smtp_server_callbacks lmtp_callbacks;
+static const struct lmtp_client_vfuncs lmtp_client_vfuncs;
+
+struct lmtp_module_register lmtp_module_register = { 0 };
+
+static struct client *clients = NULL;
+static unsigned int clients_count = 0;
+
+static bool verbose_proctitle = FALSE;
+
+static const char *client_remote_id(struct client *client)
+{
+	const char *addr;
+
+	addr = net_ip2addr(&client->remote_ip);
+	if (addr[0] == '\0')
+		addr = "local";
+	return addr;
+}
+
+static void refresh_proctitle(void)
+{
+	struct client *client;
+	string_t *title;
+
+	if (!verbose_proctitle)
+		return;
+
+	title = t_str_new(128);
+	str_append_c(title, '[');
+	switch (clients_count) {
+	case 0:
+		str_append(title, "idling");
+		break;
+	case 1:
+		client = clients;
+		str_append(title, client_remote_id(client));
+		str_append_c(title, ' ');
+		str_append(title, smtp_server_state_names[client->state.state]);
+		if (client->state.args != NULL && *client->state.args != '\0') {
+			str_append_c(title, ' ');
+			str_append(title, client->state.args);
+		}
+		break;
+	default:
+		str_printfa(title, "%u connections", clients_count);
+		break;
+	}
+	str_append_c(title, ']');
+	process_title_set(str_c(title));
+}
+
+static void client_load_modules(struct client *client)
+{
+        struct module_dir_load_settings mod_set;
+
+        i_zero(&mod_set);
+        mod_set.abi_version = DOVECOT_ABI_VERSION;
+        mod_set.require_init_funcs = TRUE;
+        mod_set.binary_name = "lmtp";
+
+        /* pre-load all configured mail plugins */
+        mail_storage_service_modules =
+                module_dir_load_missing(mail_storage_service_modules,
+                                        client->lmtp_set->mail_plugin_dir,
+                                        client->lmtp_set->mail_plugins,
+                                        &mod_set);
+	module_dir_init(mail_storage_service_modules);
+}
+
+static void client_raw_user_create(struct client *client)
+{
+	void **sets;
+
+	sets = master_service_settings_get_others(master_service);
+	client->raw_mail_user =
+		raw_storage_create_from_set(client->user_set_info, sets[0]);
+}
+
+static void client_read_settings(struct client *client, bool ssl)
+{
+	struct mail_storage_service_input input;
+	const struct setting_parser_context *set_parser;
+	struct mail_user_settings *user_set;
+	struct lmtp_settings *lmtp_set;
+	struct lda_settings *lda_set;
+	const char *error;
+
+	i_zero(&input);
+	input.module = input.service = "lmtp";
+	input.local_ip = client->local_ip;
+	input.remote_ip = client->remote_ip;
+	input.local_port = client->local_port;
+	input.remote_port = client->remote_port;
+	input.conn_secured = ssl;
+	input.conn_ssl_secured = ssl;
+	input.username = "";
+
+	if (mail_storage_service_read_settings(storage_service, &input,
+					       client->pool,
+					       &client->user_set_info,
+					       &set_parser, &error) < 0)
+		i_fatal("%s", error);
+
+	lmtp_settings_dup(set_parser, client->pool,
+			  &user_set, &lmtp_set, &lda_set);
+	const struct var_expand_table *tab =
+		mail_storage_service_get_var_expand_table(storage_service, &input);
+	if (settings_var_expand(&lmtp_setting_parser_info, lmtp_set,
+				client->pool, tab, &error) <= 0)
+		i_fatal("Failed to expand settings: %s", error);
+	client->service_set = master_service_settings_get(master_service);
+	client->user_set = user_set;
+	client->lmtp_set = lmtp_set;
+	client->unexpanded_lda_set = lda_set;
+}
+
+struct client *client_create(int fd_in, int fd_out,
+			     const struct master_service_connection *conn)
+{
+	static const char *rcpt_param_extensions[] = {
+		LMTP_RCPT_FORWARD_PARAMETER, NULL };
+	static const struct smtp_capability_extra cap_rcpt_forward = {
+		.name = LMTP_RCPT_FORWARD_CAPABILITY };
+	enum lmtp_client_workarounds workarounds;
+	struct smtp_server_settings lmtp_set;
+	struct client *client;
+	pool_t pool;
+
+	pool = pool_alloconly_create("lmtp client", 2048);
+	client = p_new(pool, struct client, 1);
+	client->pool = pool;
+	client->v = lmtp_client_vfuncs;
+	client->remote_ip = conn->remote_ip;
+	client->remote_port = conn->remote_port;
+	client->local_ip = conn->local_ip;
+	client->local_port = conn->local_port;
+	client->real_local_ip = conn->real_local_ip;
+	client->real_local_port = conn->real_local_port;
+	client->real_remote_ip = conn->real_remote_ip;
+	client->real_remote_port = conn->real_remote_port;
+	client->state_pool = pool_alloconly_create("client state", 4096);
+
+	client->event = event_create(NULL);
+	event_add_category(client->event, &event_category_lmtp);
+
+	client_read_settings(client, conn->ssl);
+	client_raw_user_create(client);
+	client_load_modules(client);
+	client->my_domain = client->unexpanded_lda_set->hostname;
+
+	if (client->service_set->verbose_proctitle)
+		verbose_proctitle = TRUE;
+
+	p_array_init(&client->module_contexts, client->pool, 5);
+
+	i_zero(&lmtp_set);
+	lmtp_set.capabilities =
+		SMTP_CAPABILITY_PIPELINING |
+		SMTP_CAPABILITY_ENHANCEDSTATUSCODES |
+		SMTP_CAPABILITY_8BITMIME |
+		SMTP_CAPABILITY_CHUNKING |
+		SMTP_CAPABILITY_XCLIENT |
+		SMTP_CAPABILITY__ORCPT;
+	if (!conn->ssl && master_service_ssl_is_enabled(master_service))
+		lmtp_set.capabilities |= SMTP_CAPABILITY_STARTTLS;
+	lmtp_set.hostname = client->unexpanded_lda_set->hostname;
+	lmtp_set.login_greeting = client->lmtp_set->login_greeting;
+	lmtp_set.max_message_size = UOFF_T_MAX;
+	lmtp_set.rcpt_param_extensions = rcpt_param_extensions;
+	lmtp_set.rcpt_domain_optional = TRUE;
+	lmtp_set.max_client_idle_time_msecs = CLIENT_IDLE_TIMEOUT_MSECS;
+	lmtp_set.rawlog_dir = client->lmtp_set->lmtp_rawlog_dir;
+	lmtp_set.event_parent = client->event;
+
+	workarounds = client->lmtp_set->parsed_workarounds;
+	if ((workarounds & LMTP_WORKAROUND_WHITESPACE_BEFORE_PATH) != 0) {
+		lmtp_set.workarounds |=
+			SMTP_SERVER_WORKAROUND_WHITESPACE_BEFORE_PATH;
+	}
+	if ((workarounds & LMTP_WORKAROUND_MAILBOX_FOR_PATH) != 0) {
+		lmtp_set.workarounds |=
+			SMTP_SERVER_WORKAROUND_MAILBOX_FOR_PATH;
+	}
+
+	client->conn = smtp_server_connection_create(
+		lmtp_server, fd_in, fd_out,
+		&conn->remote_ip, conn->remote_port, conn->ssl,
+		&lmtp_set, &lmtp_callbacks, client);
+	if (smtp_server_connection_is_trusted(client->conn)) {
+		smtp_server_connection_add_extra_capability(
+			client->conn, &cap_rcpt_forward);
+	}
+
+	DLLIST_PREPEND(&clients, client);
+	clients_count++;
+
+	e_info(client->event, "Connect from %s", client_remote_id(client));
+
+	if (hook_client_created != NULL)
+		hook_client_created(&client);
+
+	smtp_server_connection_start(client->conn);
+
+	refresh_proctitle();
+	return client;
+}
+
+void client_state_reset(struct client *client)
+{
+	i_free(client->state.args);
+
+	if (client->local != NULL)
+		lmtp_local_deinit(&client->local);
+	if (client->proxy != NULL)
+		lmtp_proxy_deinit(&client->proxy);
+
+	o_stream_unref(&client->state.mail_data_output);
+
+	i_zero(&client->state);
+	p_clear(client->state_pool);
+}
+
+void client_destroy(struct client **_client, const char *enh_code,
+		    const char *reason)
+{
+	struct client *client = *_client;
+
+	*_client = NULL;
+
+	smtp_server_connection_terminate(&client->conn,
+		(enh_code == NULL ? "4.0.0" : enh_code), reason);
+}
+
+static void
+client_default_destroy(struct client *client)
+{
+	if (client->destroyed)
+		return;
+	client->destroyed = TRUE;
+
+	clients_count--;
+	DLLIST_REMOVE(&clients, client);
+
+	if (client->raw_mail_user != NULL)
+		mail_user_deinit(&client->raw_mail_user);
+
+	client_state_reset(client);
+	event_unref(&client->event);
+	pool_unref(&client->state_pool);
+	pool_unref(&client->pool);
+
+	master_service_client_connection_destroyed(master_service);
+}
+
+static void
+client_connection_trans_start(void *context,
+			      struct smtp_server_transaction *trans)
+{
+	struct client *client = context;
+
+	client->v.trans_start(client, trans);
+}
+
+static void
+client_default_trans_start(struct client *client ATTR_UNUSED,
+			   struct smtp_server_transaction *trans ATTR_UNUSED)
+{
+	/* nothing */
+}
+
+static void
+client_connection_trans_free(void *context,
+			     struct smtp_server_transaction *trans)
+{
+	struct client *client = (struct client *)context;
+
+	client->v.trans_free(client, trans);
+}
+
+static void
+client_default_trans_free(struct client *client,
+			  struct smtp_server_transaction *trans ATTR_UNUSED)
+{
+	client_state_reset(client);
+}
+
+static void
+client_connection_state_changed(void *context,
+				enum smtp_server_state new_state,
+				const char *new_args)
+{
+	struct client *client = (struct client *)context;
+
+	i_free(client->state.args);
+
+	client->state.state = new_state;
+	client->state.args = i_strdup(new_args);
+
+	if (clients_count == 1)
+		refresh_proctitle();
+}
+
+void client_update_data_state(struct client *client, const char *new_args)
+{
+	i_assert(client->state.state == SMTP_SERVER_STATE_DATA);
+	i_free(client->state.args);
+	client->state.args = i_strdup(new_args);
+
+	if (clients_count == 1)
+		refresh_proctitle();
+}
+
+static void
+client_connection_proxy_data_updated(void *context,
+				     const struct smtp_proxy_data *data)
+{
+	struct client *client = (struct client *)context;
+
+	client->remote_ip = data->source_ip;
+	client->remote_port = data->source_port;
+
+	if (clients_count == 1)
+		refresh_proctitle();
+}
+
+static void client_connection_disconnect(void *context, const char *reason)
+{
+	struct client *client = (struct client *)context;
+
+	if (client->disconnected)
+		return;
+	client->disconnected = TRUE;
+
+	if (reason == NULL)
+		reason = "Connection closed";
+	e_info(client->event, "Disconnect from %s: %s",
+	       client_remote_id(client), reason);
+}
+
+static void client_connection_free(void *context)
+{
+	struct client *client = (struct client *)context;
+
+	client->v.destroy(client);
+}
+
+static bool client_connection_is_trusted(void *context)
+{
+	struct client *client = (struct client *)context;
+	const char *const *net;
+	struct ip_addr net_ip;
+	unsigned int bits;
+
+	if (client->lmtp_set->login_trusted_networks == NULL)
+		return FALSE;
+
+	net = t_strsplit_spaces(client->lmtp_set->login_trusted_networks, ", ");
+	for (; *net != NULL; net++) {
+		if (net_parse_range(*net, &net_ip, &bits) < 0) {
+			e_error(client->event, "login_trusted_networks: "
+				"Invalid network '%s'", *net);
+			break;
+		}
+
+		if (net_is_in_network(&client->real_remote_ip, &net_ip, bits))
+			return TRUE;
+	}
+	return FALSE;
+}
+
+void clients_destroy(void)
+{
+	while (clients != NULL) {
+		struct client *client = clients;
+		client_destroy(&client, "4.3.2", "Shutting down");
+	}
+}
+
+static const struct smtp_server_callbacks lmtp_callbacks = {
+	.conn_cmd_mail = cmd_mail,
+	.conn_cmd_rcpt = cmd_rcpt,
+	.conn_cmd_data_begin = cmd_data_begin,
+	.conn_cmd_data_continue = cmd_data_continue,
+
+	.conn_trans_start = client_connection_trans_start,
+	.conn_trans_free = client_connection_trans_free,
+
+	.conn_state_changed = client_connection_state_changed,
+
+	.conn_proxy_data_updated = client_connection_proxy_data_updated,
+
+	.conn_disconnect = client_connection_disconnect,
+	.conn_free = client_connection_free,
+
+	.conn_is_trusted = client_connection_is_trusted
+};
+
+static const struct lmtp_client_vfuncs lmtp_client_vfuncs = {
+	.destroy = client_default_destroy,
+
+	.trans_start = client_default_trans_start,
+	.trans_free = client_default_trans_free,
+
+	.cmd_mail = client_default_cmd_mail,
+	.cmd_rcpt = client_default_cmd_rcpt,
+	.cmd_data = client_default_cmd_data,
+
+	.local_deliver = lmtp_local_default_deliver,
+};