[Feature] Allow to quarantine rejected messages using milter interface

src/libserver/milter.c

@@ -50,6 +50,7 @@ struct rspamd_milter_context {
 	gchar *spam_header;
 	void *sessions_cache;
 	gboolean discard_on_reject;
+	gboolean quarantine_on_reject;
 };
 
 static struct rspamd_milter_context *milter_ctx = NULL;
@@ -1072,6 +1073,7 @@ rspamd_milter_handle_socket (gint fd, const struct timeval *tv,
 	priv->state = RSPAMD_MILTER_READ_MORE;
 	priv->pool = rspamd_mempool_new (rspamd_mempool_suggest_size (), "milter");
 	priv->discard_on_reject = milter_ctx->discard_on_reject;
+	priv->quarantine_on_reject = milter_ctx->quarantine_on_reject;
 
 	if (pool) {
 		/* Copy tag */
@@ -1567,8 +1569,13 @@ rspamd_milter_process_milter_block (struct rspamd_milter_session *session,
 				priv->discard_on_reject = TRUE;
 				msg_info_milter ("discard message instead of rejection");
 			}
+			else if (strcmp (ucl_object_tostring (elt), "quarantine") == 0) {
+				priv->quarantine_on_reject = TRUE;
+				msg_info_milter ("quarantine message instead of rejection");
+			}
 			else {
 				priv->discard_on_reject = FALSE;
+				priv->quarantine_on_reject = FALSE;
 			}
 		}
 
@@ -1713,6 +1720,10 @@ rspamd_milter_send_task_results (struct rspamd_milter_session *session,
 		if (priv->discard_on_reject) {
 			rspamd_milter_send_action (session, RSPAMD_MILTER_DISCARD);
 		}
+		else if (priv->quarantine_on_reject) {
+			/* TODO: need to add quarantine message */
+			rspamd_milter_send_action (session, RSPAMD_MILTER_QUARANTINE);
+		}
 		else {
 			rcode = rspamd_fstring_new_init (RSPAMD_MILTER_RCODE_REJECT,
 					sizeof (RSPAMD_MILTER_RCODE_REJECT) - 1);
@@ -1789,7 +1800,7 @@ cleanup:
 
 void
 rspamd_milter_init_library (const gchar *spam_header, void *sessions_cache,
-		gboolean discard_on_reject)
+		gboolean discard_on_reject, gboolean quarantine_on_reject)
 {
 	if (milter_ctx) {
 		g_free (milter_ctx->spam_header);
@@ -1807,6 +1818,7 @@ rspamd_milter_init_library (const gchar *spam_header, void *sessions_cache,
 
 	milter_ctx->sessions_cache = sessions_cache;
 	milter_ctx->discard_on_reject = discard_on_reject;
+	milter_ctx->quarantine_on_reject = quarantine_on_reject;
 }
 
 rspamd_mempool_t *

src/libserver/milter.h

@@ -36,7 +36,8 @@ enum rspamd_milter_reply {
 	RSPAMD_MILTER_TEMPFAIL = 't',
 	RSPAMD_MILTER_REPLYCODE = 'y',
 	RSPAMD_MILTER_OPTNEG = 'O',
-	RSPAMD_MILTER_PROGRESS = 'p'
+	RSPAMD_MILTER_PROGRESS = 'p',
+	RSPAMD_MILTER_QUARANTINE = 'q',
 };
 
 struct rspamd_email_address;
@@ -151,7 +152,8 @@ void rspamd_milter_send_task_results (struct rspamd_milter_session *session,
  * @param spam_header spam header name (must NOT be NULL)
  */
 void rspamd_milter_init_library (const gchar *spam_header,
-		void *sessions_cache, gboolean discard_on_reject);
+		void *sessions_cache, gboolean discard_on_reject,
+		gboolean quarantine_on_reject);
 
 /**
  * Returns pool for a session

src/libserver/milter_internal.h

@@ -67,6 +67,7 @@ struct rspamd_milter_private {
 	enum rspamd_milter_io_state state;
 	int fd;
 	gboolean discard_on_reject;
+	gboolean quarantine_on_reject;
 	gboolean no_action;
 };
 
@@ -124,10 +125,12 @@ enum rspamd_milter_io_cmd {
 #define RSPAMD_MILTER_FLAG_ADDRCPT	(1L<<2)	/* filter may add recipients */
 #define RSPAMD_MILTER_FLAG_DELRCPT	(1L<<3)	/* filter may delete recipients */
 #define RSPAMD_MILTER_FLAG_CHGHDRS	(1L<<4)	/* filter may change/delete headers */
+#define RSPAMD_MILTER_FLAG_QUARANTINE	(1L<<5)	/* filter may request quarantine */
 
 #define RSPAMD_MILTER_ACTIONS_MASK \
 	(RSPAMD_MILTER_FLAG_ADDHDRS | RSPAMD_MILTER_FLAG_ADDRCPT | \
-	RSPAMD_MILTER_FLAG_DELRCPT | RSPAMD_MILTER_FLAG_CHGHDRS)
+	RSPAMD_MILTER_FLAG_DELRCPT | RSPAMD_MILTER_FLAG_CHGHDRS | \
+	RSPAMD_MILTER_FLAG_QUARANTINE)
 
 enum rspamd_milter_connect_proto {
 	RSPAMD_MILTER_CONN_UNKNOWN = 'U',

src/rspamd_proxy.c

@@ -138,6 +138,8 @@ struct rspamd_proxy_ctx {
 	gboolean milter;
 	/* Discard messages instead of rejecting them */
 	gboolean discard_on_reject;
+	/* Quarantine messages instead of rejecting them */
+	gboolean quarantine_on_reject;
 	/* Milter spam header */
 	gchar *spam_header;
 	/* Sessions cache */
@@ -810,6 +812,14 @@ init_rspamd_proxy (struct rspamd_config *cfg)
 			G_STRUCT_OFFSET (struct rspamd_proxy_ctx, discard_on_reject),
 			0,
 			"Tell MTA to discard rejected messages silently");
+	rspamd_rcl_register_worker_option (cfg,
+			type,
+			"quarantine_on_reject",
+			rspamd_rcl_parse_struct_boolean,
+			ctx,
+			G_STRUCT_OFFSET (struct rspamd_proxy_ctx, quarantine_on_reject),
+			0,
+			"Tell MTA to quarantine rejected messages");
 	rspamd_rcl_register_worker_option (cfg,
 			type,
 			"spam_header",
@@ -2115,7 +2125,7 @@ start_rspamd_proxy (struct rspamd_worker *worker) {
 	}
 
 	rspamd_milter_init_library (ctx->spam_header, ctx->sessions_cache,
-			ctx->discard_on_reject);
+			ctx->discard_on_reject, ctx->quarantine_on_reject);
 	rspamd_lua_run_postloads (ctx->cfg->lua_state, ctx->cfg, ctx->ev_base,
 			worker);