* Add ability to set filters for smtp worker for each smtp stage

* Add very initial version of DNS resolver (many things to be done)

1 files changed, 206 insertions, 0 deletions

diff --git a/src/dns.h b/src/dns.h
new file mode 100644
index 000000000..955d01c8c
--- /dev/null
+++ b/src/dns.h
@@ -0,0 +1,206 @@
+#ifndef RSPAMD_DNS_H
+#define RSPAMD_DNS_H
+
+#include "config.h"
+#include "mem_pool.h"
+#include "events.h"
+#include "upstream.h"
+
+#define MAX_SERVERS 16
+
+#define DNS_D_MAXLABEL	63	/* + 1 '\0' */
+#define DNS_D_MAXNAME	255	/* + 1 '\0' */
+
+struct rspamd_dns_reply;
+
+typedef void (*dns_callback_type) (struct rspamd_dns_reply *reply, gpointer arg);
+/**
+ * Implements DNS server
+ */
+struct rspamd_dns_server {
+	struct upstream up;					/**< upstream structure						*/
+	struct in_addr addr;				/**< address of DNS server					*/
+	char *name;							/**< name of DNS server						*/
+	int sock;							/**< persistent socket						*/
+};
+
+#define DNS_K_TEA_KEY_SIZE	16
+
+struct dns_k_tea {
+	uint32_t key[DNS_K_TEA_KEY_SIZE / sizeof (uint32_t)];
+	unsigned cycles;
+}; /* struct dns_k_tea */
+
+struct dns_k_permutor {
+	unsigned stepi, length, limit;
+	unsigned shift, mask, rounds;
+
+	struct dns_k_tea tea;
+};
+
+struct rspamd_dns_resolver {
+	struct rspamd_dns_server servers[MAX_SERVERS];
+	gint servers_num;					/**< number of DNS servers registered		*/
+	GHashTable *requests;				/**< requests in flight						*/
+	struct dns_k_permutor *permutor;	/**< permutor for randomizing request id	*/
+	guint request_timeout;
+	guint max_retransmits;
+};
+
+struct dns_header;
+struct dns_query;
+
+struct rspamd_dns_request {
+	memory_pool_t *pool;				/**< pool associated with request			*/
+	struct rspamd_dns_resolver *resolver;
+	struct rspamd_dns_server *server;
+	dns_callback_type func;
+	gpointer arg;
+	struct event timer_event;
+	struct event io_event;
+	struct timeval tv;
+	guint retransmits;
+	guint16 id;
+	struct rspamd_async_session *session;
+	struct rspamd_dns_reply *reply;
+	guint8 *packet;
+	off_t pos;
+	guint packet_len;
+	int sock;
+};
+
+enum rspamd_request_type {
+	DNS_REQUEST_A = 0,
+	DNS_REQUEST_PTR,
+	DNS_REQUEST_MX,
+	DNS_REQUEST_TXT
+};
+
+union rspamd_reply_element {
+	struct {
+		struct in_addr addr;
+	} a;
+	struct {
+		char *name;
+	} ptr;
+	struct {
+		char *name;
+		guint32 priority;
+	} mx;
+	struct {
+		char *data;
+	} txt;
+};
+
+enum dns_rcode {
+	DNS_RC_NOERROR	= 0,
+	DNS_RC_FORMERR	= 1,
+	DNS_RC_SERVFAIL	= 2,
+	DNS_RC_NXDOMAIN	= 3,
+	DNS_RC_NOTIMP	= 4,
+	DNS_RC_REFUSED	= 5,
+	DNS_RC_YXDOMAIN	= 6,
+	DNS_RC_YXRRSET	= 7,
+	DNS_RC_NXRRSET	= 8,
+	DNS_RC_NOTAUTH	= 9,
+	DNS_RC_NOTZONE	= 10,
+};
+	
+struct rspamd_dns_reply {
+	enum rspamd_request_type type;
+	struct rspamd_dns_request *request;
+	GList *elements;
+};
+
+/* Internal DNS structs */
+
+struct dns_header {
+		unsigned qid:16;
+
+#if __BYTE_ORDER == BIG_ENDIAN
+		unsigned qr:1;
+		unsigned opcode:4;
+		unsigned aa:1;
+		unsigned tc:1;
+		unsigned rd:1;
+
+		unsigned ra:1;
+		unsigned unused:3;
+		unsigned rcode:4;
+#else
+		unsigned rd:1;
+		unsigned tc:1;
+		unsigned aa:1;
+		unsigned opcode:4;
+		unsigned qr:1;
+
+		unsigned rcode:4;
+		unsigned unused:3;
+		unsigned ra:1;
+#endif
+
+		unsigned qdcount:16;
+		unsigned ancount:16;
+		unsigned nscount:16;
+		unsigned arcount:16;
+};
+
+enum dns_section {
+	DNS_S_QD		= 0x01,
+#define DNS_S_QUESTION		DNS_S_QD
+
+	DNS_S_AN		= 0x02,
+#define DNS_S_ANSWER		DNS_S_AN
+
+	DNS_S_NS		= 0x04,
+#define DNS_S_AUTHORITY		DNS_S_NS
+
+	DNS_S_AR		= 0x08,
+#define DNS_S_ADDITIONAL	DNS_S_AR
+
+	DNS_S_ALL		= 0x0f
+}; /* enum dns_section */
+
+enum dns_opcode {
+	DNS_OP_QUERY	= 0,
+	DNS_OP_IQUERY	= 1,
+	DNS_OP_STATUS	= 2,
+	DNS_OP_NOTIFY	= 4,
+	DNS_OP_UPDATE	= 5,
+}; /* dns_opcode */
+
+enum dns_type {
+	DNS_T_A		= 1,
+	DNS_T_NS	= 2,
+	DNS_T_CNAME	= 5,
+	DNS_T_SOA	= 6,
+	DNS_T_PTR	= 12,
+	DNS_T_MX	= 15,
+	DNS_T_TXT	= 16,
+	DNS_T_AAAA	= 28,
+	DNS_T_SRV	= 33,
+	DNS_T_SSHFP	= 44,
+	DNS_T_SPF	= 99,
+
+	DNS_T_ALL	= 255
+}; /* enum dns_type */
+
+enum dns_class {
+	DNS_C_IN	= 1,
+
+	DNS_C_ANY	= 255
+}; /* enum dns_class */
+
+struct dns_query {
+	char *qname;
+	unsigned qtype:16;
+	unsigned qclass:16;
+};
+
+/* Rspamd DNS API */
+struct rspamd_dns_resolver *dns_resolver_init (void);
+gboolean make_dns_request (struct rspamd_dns_resolver *resolver, 
+		struct rspamd_async_session *session, memory_pool_t *pool, dns_callback_type cb, 
+		gpointer ud, enum rspamd_request_type type, ...);
+
+#endif