*/
#include "platform.h"
#include <gnunet_util_lib.h>
-#include <gnunet_namestore_service.h>
+#include <gnunet_dnsparser_lib.h>
+#include <gnunet_gns_service.h>
+
+/**
+ * Timeout for DNS requests.
+ */
+#define TIMEOUT GNUNET_TIME_UNIT_MINUTES
/**
* Data kept per request.
*/
struct Request
{
+ /**
+ * Socket to use for sending the reply.
+ */
+ struct GNUNET_NETWORK_Handle *lsock;
+
+ /**
+ * Destination address to use.
+ */
+ const void *addr;
+
+ /**
+ * Initially, this is the DNS request, it will then be
+ * converted to the DNS response.
+ */
+ struct GNUNET_DNSPARSER_Packet *packet;
+
+ /**
+ * Our GNS request handle.
+ */
+ struct GNUNET_GNS_LookupRequest *lookup;
+
+ /**
+ * Task run on timeout or shutdown to clean up without
+ * response.
+ */
+ GNUNET_SCHEDULER_TaskIdentifier timeout_task;
+
+ /**
+ * Number of bytes in 'addr'.
+ */
+ size_t addr_len;
};
/**
- * Listen socket.
+ * Handle to GNS resolver.
+ */
+struct GNUNET_GNS_Handle *gns;
+
+/**
+ * Listen socket for IPv4.
+ */
+static struct GNUNET_NETWORK_Handle *listen_socket4;
+
+/**
+ * Listen socket for IPv6.
+ */
+static struct GNUNET_NETWORK_Handle *listen_socket6;
+
+/**
+ * Task for IPv4 socket.
+ */
+static GNUNET_SCHEDULER_TaskIdentifier t4;
+
+/**
+ * Task for IPv6 socket.
*/
-static struct GNUNET_NETWORK_Handle *listen_socket;
+static GNUNET_SCHEDULER_TaskIdentifier t6;
/**
do_shutdown (void *cls,
const struct GNUNET_SCHEDULER_TaskContext *tc)
{
+ if (GNUNET_SCHEDULER_NO_TASK != t4)
+ GNUNET_SCHEDULER_cancel (t4);
+ if (GNUNET_SCHEDULER_NO_TASK != t6)
+ GNUNET_SCHEDULER_cancel (t6);
+ if (NULL != listen_socket4)
+ {
+ GNUNET_NETWORK_socket_close (listen_socket4);
+ listen_socket4 = NULL;
+ }
+ if (NULL != listen_socket6)
+ {
+ GNUNET_NETWORK_socket_close (listen_socket6);
+ listen_socket6 = NULL;
+ }
+ GNUNET_GNS_disconnect (gns);
+ gns = NULL;
+}
+
+
+/**
+ * Send the response for the given request and clean up.
+ *
+ * @param request context for the request.
+ */
+static void
+send_response (struct Request *request)
+{
+ char *buf;
+ size_t size;
+
+ if (GNUNET_SYSERR ==
+ GNUNET_DNSPARSER_pack (request->packet,
+ UINT16_MAX /* is this not too much? */,
+ &buf,
+ &size))
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
+ _("Failed to pack DNS response into UDP packet!\n"));
+ }
+ else
+ {
+ if (size !=
+ GNUNET_NETWORK_socket_sendto (request->lsock,
+ buf, size,
+ request->addr,
+ request->addr_len))
+ GNUNET_log_strerror (GNUNET_ERROR_TYPE_WARNING, "sendto");
+ GNUNET_free (buf);
+ }
+ GNUNET_SCHEDULER_cancel (request->timeout_task);
+ GNUNET_DNSPARSER_free_packet (request->packet);
+ GNUNET_free (request);
+}
+
+
+/**
+ * Task run on timeout. Cleans up request.
+ *
+ * @param cls 'struct Request' of the request to clean up
+ * @param tc scheduler context
+ */
+static void
+do_timeout (void *cls,
+ const struct GNUNET_SCHEDULER_TaskContext *tc)
+{
+ struct Request *request = cls;
+
+ GNUNET_DNSPARSER_free_packet (request->packet);
+ GNUNET_GNS_cancel_lookup_request (request->lookup);
+ GNUNET_free (request);
+}
+
+
+/**
+ * Iterator called on obtained result for a GNS
+ * lookup
+ *
+ * @param cls closure
+ * @param name "name" of the original lookup
+ * @param rd_count number of records
+ * @param rd the records in reply
+ */
+static void
+result_processor (void *cls,
+ uint32_t rd_count,
+ const struct GNUNET_NAMESTORE_RecordData *rd)
+{
+ struct Request *request = cls;
+
+ // FIXME: is 'processor' called only once or
+ // possibly more than once?
+ request->lookup = NULL;
+ GNUNET_break (0);
+ // FIXME: convert 'rd' to response here...
+ send_response (request);
+}
+
+
+/**
+ * Handle DNS request.
+ *
+ * @param lsock socket to use for sending the reply
+ * @param addr address to use for sending the reply
+ * @param addr_len number of bytes in addr
+ * @param udp_msg DNS request payload
+ * @param udp_msg_size number of bytes in udp_msg
+ */
+static void
+handle_request (struct GNUNET_NETWORK_Handle *lsock,
+ const void *addr,
+ size_t addr_len,
+ const char *udp_msg,
+ size_t udp_msg_size)
+{
+ struct Request *request;
+ struct GNUNET_DNSPARSER_Packet *packet;
+
+ packet = GNUNET_DNSPARSER_parse (udp_msg, udp_msg_size);
+ if (NULL == packet)
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
+ _("Received malformed DNS request from %s\n"),
+ GNUNET_a2s (addr, addr_len));
+ return;
+ }
+ request = GNUNET_malloc (sizeof (struct Request) + addr_len);
+ request->lsock = lsock;
+ request->packet = packet;
+ request->addr = &request[1];
+ request->addr_len = addr_len;
+ memcpy (&request[1], addr, addr_len);
+ request->timeout_task = GNUNET_SCHEDULER_add_delayed (TIMEOUT,
+ &do_timeout,
+ request);
+ // FIXME: extract name and type from 'request->packet'
+ const char *name = "foo";
+ enum GNUNET_GNS_RecordType type = GNUNET_GNS_RECORD_A;
+ request->lookup = GNUNET_GNS_lookup (gns,
+ name,
+ type,
+ GNUNET_NO,
+ NULL,
+ &result_processor,
+ request);
+}
+
+
+/**
+ * Task to read IPv4 DNS packets.
+ *
+ * @param cls the 'listen_socket4'
+ * @param tc scheduler context
+ */
+static void
+read_dns4 (void *cls,
+ const struct GNUNET_SCHEDULER_TaskContext *tc)
+{
+ struct sockaddr_in v4;
+ socklen_t addrlen;
+ ssize_t size;
+
+ GNUNET_assert (listen_socket4 == cls);
+ t4 = GNUNET_SCHEDULER_add_read_net (GNUNET_TIME_UNIT_FOREVER_REL,
+ listen_socket4,
+ &read_dns4,
+ listen_socket4);
+ if (0 == (GNUNET_SCHEDULER_REASON_READ_READY & tc->reason))
+ return; /* shutdown? */
+ size = GNUNET_NETWORK_socket_recvfrom_amount (listen_socket4);
+ if (0 > size)
+ {
+ GNUNET_break (0);
+ return; /* read error!? */
+ }
+ {
+ char buf[size];
+
+ addrlen = sizeof (v4);
+ GNUNET_break (size ==
+ GNUNET_NETWORK_socket_recvfrom (listen_socket4,
+ buf,
+ size,
+ (struct sockaddr *) &v4,
+ &addrlen));
+ handle_request (listen_socket4, &v4, addrlen,
+ buf, size);
+ }
+}
+
+
+/**
+ * Task to read IPv6 DNS packets.
+ *
+ * @param cls the 'listen_socket6'
+ * @param tc scheduler context
+ */
+static void
+read_dns6 (void *cls,
+ const struct GNUNET_SCHEDULER_TaskContext *tc)
+{
+ struct sockaddr_in6 v6;
+ socklen_t addrlen;
+ ssize_t size;
+
+ GNUNET_assert (listen_socket6 == cls);
+ t6 = GNUNET_SCHEDULER_add_read_net (GNUNET_TIME_UNIT_FOREVER_REL,
+ listen_socket6,
+ &read_dns6,
+ listen_socket6);
+ if (0 == (GNUNET_SCHEDULER_REASON_READ_READY & tc->reason))
+ return; /* shutdown? */
+ size = GNUNET_NETWORK_socket_recvfrom_amount (listen_socket6);
+ if (0 > size)
+ {
+ GNUNET_break (0);
+ return; /* read error!? */
+ }
+ {
+ char buf[size];
+
+ addrlen = sizeof (v6);
+ GNUNET_break (size ==
+ GNUNET_NETWORK_socket_recvfrom (listen_socket6,
+ buf,
+ size,
+ (struct sockaddr *) &v6,
+ &addrlen));
+ handle_request (listen_socket6, &v6, addrlen,
+ buf, size);
+ }
}
run (void *cls, char *const *args, const char *cfgfile,
const struct GNUNET_CONFIGURATION_Handle *cfg)
{
+ gns = GNUNET_GNS_connect (cfg);
+ if (NULL == gns)
+ return;
+ listen_socket4 = GNUNET_NETWORK_socket_create (PF_INET,
+ SOCK_DGRAM,
+ IPPROTO_UDP);
+ if (NULL != listen_socket4)
+ {
+ struct sockaddr_in v4;
+
+ memset (&v4, 0, sizeof (v4));
+ v4.sin_family = AF_INET;
+#if HAVE_SOCKADDR_IN_SIN_LEN
+ v4.sin_len = sizeof (v4);
+#endif
+ v4.sin_port = htons (53);
+ if (GNUNET_OK !=
+ GNUNET_NETWORK_socket_bind (listen_socket4,
+ (struct sockaddr *) &v4,
+ sizeof (v4)))
+ {
+ GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR, "bind");
+ GNUNET_NETWORK_socket_close (listen_socket4);
+ listen_socket4 = NULL;
+ }
+ }
+ listen_socket6 = GNUNET_NETWORK_socket_create (PF_INET6,
+ SOCK_DGRAM,
+ IPPROTO_UDP);
+ if (NULL != listen_socket6)
+ {
+ struct sockaddr_in6 v6;
+
+ memset (&v6, 0, sizeof (v6));
+ v6.sin6_family = AF_INET6;
+#if HAVE_SOCKADDR_IN_SIN_LEN
+ v6.sin6_len = sizeof (v6);
+#endif
+ v6.sin6_port = htons (53);
+ if (GNUNET_OK !=
+ GNUNET_NETWORK_socket_bind (listen_socket6,
+ (struct sockaddr *) &v6,
+ sizeof (v6)))
+ {
+ GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR, "bind");
+ GNUNET_NETWORK_socket_close (listen_socket6);
+ listen_socket6 = NULL;
+ }
+ }
+ if ( (NULL == listen_socket4) &&
+ (NULL == listen_socket6) )
+ return;
+ if (NULL != listen_socket4)
+ t4 = GNUNET_SCHEDULER_add_read_net (GNUNET_TIME_UNIT_FOREVER_REL,
+ listen_socket4,
+ &read_dns4,
+ listen_socket4);
+ if (NULL != listen_socket6)
+ t6 = GNUNET_SCHEDULER_add_read_net (GNUNET_TIME_UNIT_FOREVER_REL,
+ listen_socket6,
+ &read_dns6,
+ listen_socket6);
+
GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_FOREVER_REL,
&do_shutdown, NULL);
}
projects / oweals / gnunet.git / commitdiff