*/
/**
+ *
+ * TODO:
+ * - Write xquery and block plugin
+ * - The smaller FIXME issues all around
+ *
* @file gns/gnunet-service-gns.c
* @brief GNUnet GNS service
* @author Martin Schanzenbach
#include "gnunet_util_lib.h"
#include "gnunet_transport_service.h"
#include "gnunet_dns_service.h"
+#include "gnunet_dnsparser_lib.h"
+#include "gnunet_dht_service.h"
+#include "gnunet_namestore_service.h"
#include "gnunet_gns_service.h"
-#include "gnunet-service-gns.h"
+#include "block_gns.h"
+#include "gns.h"
+
+#define DHT_OPERATION_TIMEOUT GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_SECONDS, 5)
+#define DHT_LOOKUP_TIMEOUT DHT_OPERATION_TIMEOUT
+#define DHT_GNS_REPLICATION_LEVEL 5
+
+/* Ignore for now not used anyway and probably never will */
+#define GNUNET_MESSAGE_TYPE_GNS_CLIENT_LOOKUP 23
+#define GNUNET_MESSAGE_TYPE_GNS_CLIENT_RESULT 24
+
+/**
+ * Handle to a currenty pending resolution
+ */
+struct GNUNET_GNS_ResolverHandle
+{
+ /* The name to resolve */
+ char *name;
+
+ /* the request handle to reply to */
+ struct GNUNET_DNS_RequestHandle *request_handle;
+
+ /* the dns parser packet received */
+ struct GNUNET_DNSPARSER_Packet *packet;
+
+ /* the query parsed from the packet */
+
+ struct GNUNET_DNSPARSER_Query *query;
+
+ /* has this query been answered? how many matches */
+ int answered;
+
+ /* the authoritative zone to query */
+ GNUNET_HashCode authority;
+
+ /* the name of the authoritative zone to query */
+ char *authority_name;
+
+ /**
+ * we have an authority in namestore that
+ * may be able to resolve
+ */
+ int authority_found;
+
+ /* a handle for dht lookups. should be NULL if no lookups are in progress */
+ struct GNUNET_DHT_GetHandle *get_handle;
+
+ /* timeout task for dht lookups */
+ GNUNET_SCHEDULER_TaskIdentifier dht_timeout_task;
+
+};
/**
* Our handle to the DNS handler library
*/
-struct GNUNET_DNS_Handle *dns_handler;
+struct GNUNET_DNS_Handle *dns_handle;
+
+/**
+ * Our handle to the DHT
+ */
+struct GNUNET_DHT_Handle *dht_handle;
+
+/**
+ * Our zone's private key
+ */
+struct GNUNET_CRYPTO_RsaPrivateKey *zone_key;
+
+/**
+ * Our handle to the namestore service
+ * FIXME maybe need a second handle for iteration
+ */
+struct GNUNET_NAMESTORE_Handle *namestore_handle;
+
+/**
+ * Handle to iterate over our authoritative zone in namestore
+ */
+struct GNUNET_NAMESTORE_ZoneIterator *namestore_iter;
/**
* The configuration the GNS service is running with
*/
-const struct GNUNET_CONFIGURATION_Handle *GDS_cfg;
+const struct GNUNET_CONFIGURATION_Handle *GNS_cfg;
+
+/**
+ * Our notification context.
+ */
+static struct GNUNET_SERVER_NotificationContext *nc;
+
+/**
+ * Our zone hash
+ */
+GNUNET_HashCode zone_hash;
+
+/**
+ * Our tld. Maybe get from config file
+ */
+const char* gnunet_tld = ".gnunet";
+
+/**
+ * Useful for zone update for DHT put
+ */
+static int num_public_records = 3600;
+struct GNUNET_TIME_Relative dht_update_interval;
+GNUNET_SCHEDULER_TaskIdentifier zone_update_taskid = GNUNET_SCHEDULER_NO_TASK;
+
+/* Prototypes */
+static void reply_to_dns(struct GNUNET_GNS_ResolverHandle *answer,
+ uint32_t rd_count,
+ const struct GNUNET_NAMESTORE_RecordData *rd);
+static void resolve_name(struct GNUNET_GNS_ResolverHandle *rh);
/**
* Task run during shutdown.
static void
shutdown_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
{
- GNUNET_DNS_disconnect(dns_handle);
+ /* Kill zone task for it may make the scheduler hang */
+ if (zone_update_taskid)
+ GNUNET_SCHEDULER_cancel(zone_update_taskid);
+
+ GNUNET_DNS_disconnect(dns_handle);
+ GNUNET_NAMESTORE_disconnect(namestore_handle, 1);
+ GNUNET_DHT_disconnect(dht_handle);
+}
+
+/**
+ * Callback when record data is put into namestore
+ *
+ * @param cls the closure
+ * @param success GNUNET_OK on success
+ * @param emsg the error message. NULL if SUCCESS==GNUNET_OK
+ */
+void
+on_namestore_record_put_result(void *cls,
+ int32_t success,
+ const char *emsg)
+{
+ if (GNUNET_NO == success)
+ {
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "records already in namestore\n");
+ return;
+ }
+ else if (GNUNET_YES == success)
+ {
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
+ "records successfully put in namestore\n");
+ return;
+ }
+
+ GNUNET_log(GNUNET_ERROR_TYPE_ERROR,
+ "Error putting records into namestore: %s\n", emsg);
+}
+
+/**
+ * Handle timeout for DHT requests
+ *
+ * @param cls the request handle as closure
+ * @param tc the task context
+ */
+static void
+dht_lookup_timeout(void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
+{
+ struct GNUNET_GNS_ResolverHandle *rh = cls;
+
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
+ "dht lookup for query %s (type=%d) timed out.\n",
+ rh->name, rh->query->type);
+
+ GNUNET_DHT_get_stop (rh->get_handle);
+ reply_to_dns(rh, 0, NULL);
+}
+
+/**
+ * Function called when we get a result from the dht
+ * for our query
+ *
+ * @param cls the request handle
+ * @param exp lifetime
+ * @param key the key the record was stored under
+ * @param get_path get path
+ * @param get_path_length get path length
+ * @param put_path put path
+ * @param put_path_length put path length
+ * @param type the block type
+ * @param size the size of the record
+ * @param data the record data
+ */
+static void
+process_authority_dht_result(void* cls,
+ struct GNUNET_TIME_Absolute exp,
+ const GNUNET_HashCode * key,
+ const struct GNUNET_PeerIdentity *get_path,
+ unsigned int get_path_length,
+ const struct GNUNET_PeerIdentity *put_path,
+ unsigned int put_path_length,
+ enum GNUNET_BLOCK_Type type,
+ size_t size, const void *data)
+{
+ struct GNUNET_GNS_ResolverHandle *rh;
+ struct GNSNameRecordBlock *nrb;
+ uint32_t num_records;
+ char* name = NULL;
+ char* rd_data = (char*) data;
+ int i;
+ int rd_size;
+ GNUNET_HashCode zone, name_hash;
+
+ if (data == NULL)
+ return;
+
+ //FIXME check expiration?
+
+ rh = (struct GNUNET_GNS_ResolverHandle *)cls;
+ nrb = (struct GNSNameRecordBlock*)data;
+
+ /* stop dht lookup and timeout task */
+ GNUNET_DHT_get_stop (rh->get_handle);
+ GNUNET_SCHEDULER_cancel(rh->dht_timeout_task);
+
+ rh->get_handle = NULL;
+ num_records = ntohl(nrb->rd_count);
+ name = (char*)&nrb[1];
+ {
+ struct GNUNET_NAMESTORE_RecordData rd[num_records];
+
+ rd_data += strlen(name) + 1 + sizeof(struct GNSNameRecordBlock);
+ rd_size = size - strlen(name) - 1 - sizeof(struct GNSNameRecordBlock);
+
+ if (GNUNET_SYSERR == GNUNET_NAMESTORE_records_deserialize (rd_size,
+ rd_data,
+ num_records,
+ rd))
+ {
+ GNUNET_log(GNUNET_ERROR_TYPE_ERROR, "Error deserializing data!\n");
+ return;
+ }
+
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
+ "Got name: %s (wanted %s)\n", name, rh->authority_name);
+ for (i=0; i<num_records; i++)
+ {
+
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
+ "Got name: %s (wanted %s)\n", name, rh->authority_name);
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
+ "Got type: %d (wanted %d)\n",
+ rd[i].record_type, GNUNET_GNS_RECORD_PKEY);
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
+ "Got data length: %d\n", rd[i].data_size);
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
+ "Got flag %d\n", rd[i].flags);
+
+ if ((strcmp(name, rh->authority_name) == 0) &&
+ (rd[i].record_type == GNUNET_GNS_RECORD_PKEY))
+ {
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Authority found in DHT\n");
+ rh->answered = 1;
+ GNUNET_CRYPTO_hash(
+ (struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded *)rd[i].data,
+ rd[i].data_size,
+ &rh->authority);
+ }
+
+ }
+
+
+ GNUNET_CRYPTO_hash(name, strlen(name), &name_hash);
+ GNUNET_CRYPTO_hash_xor(key, &name_hash, &zone);
+
+ /* Save to namestore */
+ if (0 == GNUNET_CRYPTO_hash_cmp(&zone_hash, &zone))
+ {
+ GNUNET_NAMESTORE_record_put (namestore_handle,
+ &nrb->public_key,
+ name,
+ exp,
+ num_records,
+ rd,
+ &nrb->signature,
+ &on_namestore_record_put_result, //cont
+ NULL); //cls
+ }
+ }
+
+ if (rh->answered)
+ {
+ rh->answered = 0;
+ resolve_name(rh);
+ return;
+ }
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "No authority in records\n");
+ reply_to_dns(rh, 0, NULL);
+}
+
+/**
+ * Start DHT lookup for a name -> PKEY (compare NS) record in
+ * query->authority's zone
+ *
+ * @param rh the pending gns query
+ * @param name the name of the PKEY record
+ */
+static void
+resolve_authority_dht(struct GNUNET_GNS_ResolverHandle *rh)
+{
+ uint32_t xquery;
+ GNUNET_HashCode name_hash;
+ GNUNET_HashCode lookup_key;
+
+ GNUNET_CRYPTO_hash(rh->authority_name,
+ strlen(rh->authority_name),
+ &name_hash);
+ GNUNET_CRYPTO_hash_xor(&name_hash, &rh->authority, &lookup_key);
+
+ rh->dht_timeout_task = GNUNET_SCHEDULER_add_delayed (DHT_LOOKUP_TIMEOUT,
+ &dht_lookup_timeout, rh);
+
+ xquery = htonl(GNUNET_GNS_RECORD_PKEY);
+ //FIXME how long to wait for results?
+ rh->get_handle = GNUNET_DHT_get_start(dht_handle,
+ DHT_OPERATION_TIMEOUT,
+ GNUNET_BLOCK_TYPE_GNS_NAMERECORD,
+ &lookup_key,
+ DHT_GNS_REPLICATION_LEVEL,
+ GNUNET_DHT_RO_NONE,
+ &xquery,
+ sizeof(xquery),
+ &process_authority_dht_result,
+ rh);
+
+}
+
+/**
+ * Function called when we get a result from the dht
+ * for our query
+ *
+ * @param cls the request handle
+ * @param exp lifetime
+ * @param key the key the record was stored under
+ * @param get_path get path
+ * @param get_path_length get path length
+ * @param put_path put path
+ * @param put_path_length put path length
+ * @param type the block type
+ * @param size the size of the record
+ * @param data the record data
+ */
+static void
+process_name_dht_result(void* cls,
+ struct GNUNET_TIME_Absolute exp,
+ const GNUNET_HashCode * key,
+ const struct GNUNET_PeerIdentity *get_path,
+ unsigned int get_path_length,
+ const struct GNUNET_PeerIdentity *put_path,
+ unsigned int put_path_length,
+ enum GNUNET_BLOCK_Type type,
+ size_t size, const void *data)
+{
+ struct GNUNET_GNS_ResolverHandle *rh;
+ struct GNSNameRecordBlock *nrb;
+ uint32_t num_records;
+ char* name = NULL;
+ char* rd_data = (char*)data;
+ int i;
+ int rd_size;
+
+ GNUNET_HashCode zone, name_hash;
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "got dht result (size=%d)\n", size);
+
+ if (data == NULL)
+ return;
+
+ //FIXME maybe check expiration here, check block type
+
+ rh = (struct GNUNET_GNS_ResolverHandle *)cls;
+ nrb = (struct GNSNameRecordBlock*)data;
+
+ /* stop lookup and timeout task */
+ GNUNET_DHT_get_stop (rh->get_handle);
+ GNUNET_SCHEDULER_cancel(rh->dht_timeout_task);
+
+ rh->get_handle = NULL;
+ name = (char*)&nrb[1];
+ num_records = ntohl(nrb->rd_count);
+ {
+ struct GNUNET_NAMESTORE_RecordData rd[num_records];
+
+ rd_data += strlen(name) + 1 + sizeof(struct GNSNameRecordBlock);
+ rd_size = size - strlen(name) - 1 - sizeof(struct GNSNameRecordBlock);
+
+ if (GNUNET_SYSERR == GNUNET_NAMESTORE_records_deserialize (rd_size,
+ rd_data,
+ num_records,
+ rd))
+ {
+ GNUNET_log(GNUNET_ERROR_TYPE_ERROR, "Error deserializing data!\n");
+ return;
+ }
+
+ for (i=0; i<num_records; i++)
+ {
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
+ "Got name: %s (wanted %s)\n", name, rh->name);
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
+ "Got type: %d (wanted %d)\n",
+ rd[i].record_type, rh->query->type);
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
+ "Got data length: %d\n", rd[i].data_size);
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
+ "Got flag %d\n", rd[i].flags);
+
+ if ((strcmp(name, rh->name) == 0) &&
+ (rd[i].record_type == rh->query->type))
+ {
+ rh->answered++;
+ }
+
+ }
+
+ GNUNET_CRYPTO_hash(name, strlen(name), &name_hash);
+ GNUNET_CRYPTO_hash_xor(key, &name_hash, &zone);
+
+ /**
+ * FIXME check pubkey against existing key in namestore?
+ * https://gnunet.org/bugs/view.php?id=2179
+ */
+
+ /* Save to namestore */
+ GNUNET_NAMESTORE_record_put (namestore_handle,
+ &nrb->public_key,
+ name,
+ exp,
+ num_records,
+ rd,
+ &nrb->signature,
+ &on_namestore_record_put_result, //cont
+ NULL); //cls
+
+ if (rh->answered)
+ reply_to_dns(rh, num_records, rd);
+ else
+ reply_to_dns(rh, 0, NULL);
+ }
+
+}
+
+
+
+
+/**
+ * Start DHT lookup for a (name -> query->record_type) record in
+ * query->authority's zone
+ *
+ * @param rh the pending gns query context
+ * @param name the name to query record
+ */
+static void
+resolve_name_dht(struct GNUNET_GNS_ResolverHandle *rh, const char* name)
+{
+ uint32_t xquery;
+ GNUNET_HashCode name_hash;
+ GNUNET_HashCode lookup_key;
+ struct GNUNET_CRYPTO_HashAsciiEncoded lookup_key_string;
+
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
+ "A\n");
+
+ GNUNET_CRYPTO_hash(name, strlen(name), &name_hash);
+ GNUNET_CRYPTO_hash_xor(&name_hash, &rh->authority, &lookup_key);
+ GNUNET_CRYPTO_hash_to_enc (&lookup_key, &lookup_key_string);
+
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
+ "starting dht lookup for %s with key: %s\n",
+ name, (char*)&lookup_key_string);
+
+ rh->dht_timeout_task = GNUNET_SCHEDULER_add_delayed(DHT_LOOKUP_TIMEOUT,
+ &dht_lookup_timeout, rh);
+
+ xquery = htonl(rh->query->type);
+ //FIXME how long to wait for results?
+ rh->get_handle = GNUNET_DHT_get_start(dht_handle,
+ DHT_OPERATION_TIMEOUT,
+ GNUNET_BLOCK_TYPE_GNS_NAMERECORD,
+ &lookup_key,
+ DHT_GNS_REPLICATION_LEVEL,
+ GNUNET_DHT_RO_NONE,
+ &xquery,
+ sizeof(xquery),
+ &process_name_dht_result,
+ rh);
+
+}
+
+//Prototype
+static void
+resolve_name(struct GNUNET_GNS_ResolverHandle *rh);
+
+/**
+ * This is a callback function that should give us only PKEY
+ * records. Used to query the namestore for the authority (PKEY)
+ * for 'name'
+ *
+ * @param cls the pending query
+ * @param key the key of the zone we did the lookup
+ * @param expiration expiration date of the record data set in the namestore
+ * @param name the name for which we need an authority
+ * @param rd_count the number of records with 'name'
+ * @param rd the record data
+ * @param signature the signature of the authority for the record data
+ */
+static void
+process_authority_lookup(void* cls,
+ const struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded *key,
+ struct GNUNET_TIME_Absolute expiration,
+ const char *name,
+ unsigned int rd_count,
+ const struct GNUNET_NAMESTORE_RecordData *rd,
+ const struct GNUNET_CRYPTO_RsaSignature *signature)
+{
+ struct GNUNET_GNS_ResolverHandle *rh;
+ struct GNUNET_TIME_Relative remaining_time;
+ GNUNET_HashCode zone;
+
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Got %d records from authority lookup\n",
+ rd_count);
+
+ rh = (struct GNUNET_GNS_ResolverHandle *)cls;
+ GNUNET_CRYPTO_hash(key,
+ sizeof(struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded),
+ &zone);
+ remaining_time = GNUNET_TIME_absolute_get_remaining (expiration);
+
+ /**
+ * No authority found in namestore.
+ */
+ if (rd_count == 0)
+ {
+ /**
+ * We did not find an authority in the namestore
+ * _IF_ the current authoritative zone is us we cannot resolve
+ * _ELSE_ we can still check the _expired_ dht
+ */
+ if ((0 != GNUNET_CRYPTO_hash_cmp(&rh->authority, &zone_hash)) &&
+ (remaining_time.rel_value == 0))
+ {
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
+ "Authority %s unknown in namestore, trying dht\n",
+ rh->authority_name);
+ resolve_authority_dht(rh);
+ return;
+ }
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Authority %s unknown\n",
+ rh->authority_name);
+ reply_to_dns(rh, 0, NULL);
+ return;
+ }
+
+ //Note only 1 pkey should have been returned.. anything else would be strange
+ /**
+ * We found an authority that may be able to help us
+ * move on with query
+ */
+ int i;
+ for (i=0; i<rd_count;i++)
+ {
+
+ if (rd[i].record_type != GNUNET_GNS_RECORD_PKEY)
+ continue;
+
+ if ((GNUNET_TIME_absolute_get_remaining (rd[i].expiration)).rel_value
+ == 0)
+ {
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "This pkey is expired.\n");
+ if (remaining_time.rel_value == 0)
+ {
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
+ "This dht entry is expired. Refreshing\n");
+ resolve_authority_dht(rh);
+ }
+
+ continue;
+ }
+
+ /**
+ * Resolve rest of query with new authority
+ */
+ GNUNET_assert(rd[i].record_type == GNUNET_GNS_RECORD_PKEY);
+ GNUNET_CRYPTO_hash(rd[i].data,
+ sizeof(struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded),
+ &rh->authority);
+ resolve_name(rh);
+ return;
+ }
+
+ /**
+ * no answers found
+ */
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
+ "Authority lookup successful but no PKEY... never get here\n");
+ reply_to_dns(rh, 0, NULL);
+}
+
+
+/**
+ * Reply to client with the result from our lookup.
+ *
+ * @param rh the request handle of the lookup
+ * @param rd_count the number of records to return
+ * @param rd the record data
+ */
+static void
+reply_to_dns(struct GNUNET_GNS_ResolverHandle *rh, uint32_t rd_count,
+ const struct GNUNET_NAMESTORE_RecordData *rd)
+{
+ int i;
+ size_t len;
+ int ret;
+ char *buf;
+ struct GNUNET_DNSPARSER_Packet *packet = rh->packet;
+ struct GNUNET_DNSPARSER_Record answer_records[rh->answered];
+ struct GNUNET_DNSPARSER_Record additional_records[rd_count-(rh->answered)];
+ packet->answers = answer_records;
+ packet->additional_records = additional_records;
+
+ /**
+ * Put records in the DNS packet and modify it
+ * to a response
+ */
+ len = sizeof(struct GNUNET_DNSPARSER_Record*);
+ for (i=0; i < rd_count; i++)
+ {
+
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
+ "Adding type %d to DNS response\n", rd[i].record_type);
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Name: %s\n", rh->name);
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "QName: %s\n", rh->query->name);
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Record %d/%d\n", i+1, rd_count);
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Record len %d\n", rd[i].data_size);
+
+ if (rd[i].record_type == rh->query->type)
+ {
+ answer_records[i].name = rh->query->name;
+ answer_records[i].type = rd[i].record_type;
+ answer_records[i].data.raw.data_len = rd[i].data_size;
+ answer_records[i].data.raw.data = (char*)rd[i].data;
+ answer_records[i].expiration_time = rd[i].expiration;
+ answer_records[i].class = GNUNET_DNSPARSER_CLASS_INTERNET;//hmmn
+ }
+ else
+ {
+ additional_records[i].name = rh->query->name;
+ additional_records[i].type = rd[i].record_type;
+ additional_records[i].data.raw.data_len = rd[i].data_size;
+ additional_records[i].data.raw.data = (char*)rd[i].data;
+ additional_records[i].expiration_time = rd[i].expiration;
+ additional_records[i].class = GNUNET_DNSPARSER_CLASS_INTERNET;//hmmn
+ }
+ }
+
+ packet->num_answers = rh->answered;
+ packet->num_additional_records = rd_count-(rh->answered);
+
+ if (0 == GNUNET_CRYPTO_hash_cmp(&rh->authority, &zone_hash))
+ packet->flags.authoritative_answer = 1;
+ else
+ packet->flags.authoritative_answer = 0;
+
+ if (rd == NULL)
+ packet->flags.return_code = GNUNET_DNSPARSER_RETURN_CODE_NAME_ERROR;
+ else
+ packet->flags.return_code = GNUNET_DNSPARSER_RETURN_CODE_NO_ERROR;
+
+ packet->flags.query_or_response = 1;
+
+
+ /**
+ * Reply to DNS
+ */
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
+ "Building DNS response\n");
+ ret = GNUNET_DNSPARSER_pack (packet,
+ 1024, /* FIXME magic from dns redirector */
+ &buf,
+ &len);
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
+ "Built DNS response! (ret=%d,len=%d)\n", ret, len);
+ if (ret == GNUNET_OK)
+ {
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
+ "Answering DNS request\n");
+ GNUNET_DNS_request_answer(rh->request_handle,
+ len,
+ buf);
+ //GNUNET_free(answer);
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Answered DNS request\n");
+ }
+ else
+ {
+ GNUNET_log(GNUNET_ERROR_TYPE_ERROR,
+ "Error building DNS response! (ret=%d)", ret);
+ }
+
+ GNUNET_free(rh->name);
+ GNUNET_free(rh);
+}
+
+
+/**
+ * Namestore calls this function if we have record for this name.
+ * (or with rd_count=0 to indicate no matches)
+ *
+ * @param cls the pending query
+ * @param key the key of the zone we did the lookup
+ * @param expiration expiration date of the namestore entry
+ * @param name the name for which we need an authority
+ * @param rd_count the number of records with 'name'
+ * @param rd the record data
+ * @param signature the signature of the authority for the record data
+ */
+static void
+process_authoritative_result(void* cls,
+ const struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded *key,
+ struct GNUNET_TIME_Absolute expiration,
+ const char *name, unsigned int rd_count,
+ const struct GNUNET_NAMESTORE_RecordData *rd,
+ const struct GNUNET_CRYPTO_RsaSignature *signature)
+{
+ struct GNUNET_GNS_ResolverHandle *rh;
+ struct GNUNET_TIME_Relative remaining_time;
+ GNUNET_HashCode zone;
+
+ rh = (struct GNUNET_GNS_ResolverHandle *) cls;
+ GNUNET_CRYPTO_hash(key,
+ sizeof(struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded),
+ &zone);
+ remaining_time = GNUNET_TIME_absolute_get_remaining (expiration);
+
+ if (rd_count == 0)
+ {
+ /**
+ * Lookup terminated and no results
+ * -> DHT Phase unless data is recent
+ */
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
+ "Namestore lookup for %s terminated without results\n", name);
+
+ /**
+ * if this is not our zone we cannot rely on the namestore to be
+ * complete. -> Query DHT
+ */
+ if (GNUNET_CRYPTO_hash_cmp(&zone, &zone_hash))
+ {
+ if (remaining_time.rel_value == 0)
+ {
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
+ "trying dht...\n");
+ resolve_name_dht(rh, rh->name);
+ return;
+ }
+ else
+ {
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
+ "Record is still recent. No DHT lookup\n");
+ }
+ }
+
+ /**
+ * Our zone and no result? Cannot resolve TT
+ */
+ GNUNET_assert(rh->answered == 0);
+ reply_to_dns(rh, 0, NULL);
+ return;
+
+ }
+ else
+ {
+
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
+ "Processing additional result %s from namestore\n", name);
+ int i;
+ for (i=0; i<rd_count;i++)
+ {
+
+ if ((strcmp(name, rh->query->name) == 0)
+ && (rd[i].record_type != rh->query->type))
+ continue;
+
+ if ((GNUNET_TIME_absolute_get_remaining (rd[i].expiration)).rel_value
+ == 0)
+ {
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "This record is expired. Skipping\n");
+ continue;
+ }
+
+ rh->answered++;
+
+ }
+
+ /**
+ * no answers found
+ * consult dht if expired
+ */
+ if ((remaining_time.rel_value == 0) && (rh->answered == 0))
+ {
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
+ "This dht entry is old. Refreshing.\n");
+ resolve_name_dht(rh, name);
+ return;
+ }
+
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Found %d answer(s) to query!\n",
+ rh->answered);
+
+ reply_to_dns(rh, rd_count, rd);
+ }
+}
+
+/**
+ * Determine if this name is canonical.
+ * i.e.
+ * a.b.gnunet = not canonical
+ * a = canonical
+ *
+ * @param name the name to test
+ * @return 1 if canonical
+ */
+static int
+is_canonical(char* name)
+{
+ uint32_t len = strlen(name);
+ int i;
+
+ for (i=0; i<len; i++)
+ {
+ if (*(name+i) == '.')
+ return 0;
+ }
+ return 1;
+}
+
+/**
+ * Move one level up in the domain hierarchy and return the
+ * passed top level domain.
+ *
+ * @param name the domain
+ * @return the tld
+ */
+static char*
+pop_tld(char* name)
+{
+ uint32_t len;
+
+ if (is_canonical(name))
+ return NULL;
+
+ for (len = strlen(name); len > 0; len--)
+ {
+ if (*(name+len) == '.')
+ break;
+ }
+
+ if (len == 0)
+ return NULL;
+
+ name[len] = '\0';
+
+ return (name+len+1);
+}
+
+
+/**
+ * The first phase of resolution.
+ * First check if the name is canonical.
+ * If it is then try to resolve directly.
+ * If not then we first have to resolve the authoritative entities.
+ *
+ * @param rh the pending lookup
+ */
+static void
+resolve_name(struct GNUNET_GNS_ResolverHandle *rh)
+{
+ if (is_canonical(rh->name))
+ {
+ /* We only need to check the current zone's ns */
+ GNUNET_NAMESTORE_lookup_record(namestore_handle,
+ &rh->authority,
+ rh->name,
+ rh->query->type,
+ &process_authoritative_result,
+ rh);
+ }
+ else
+ {
+ /* We have to resolve the authoritative entity first */
+ rh->authority_name = pop_tld(rh->name);
+ GNUNET_NAMESTORE_lookup_record(namestore_handle,
+ &rh->authority,
+ rh->authority_name,
+ GNUNET_GNS_RECORD_PKEY,
+ &process_authority_lookup,
+ rh);
+ }
+}
+
+/**
+ * Entry point for name resolution
+ * Setup a new query and try to resolve
+ *
+ * @param request the request handle of the DNS request from a client
+ * @param p the DNS query packet we received
+ * @param q the DNS query we received parsed from p
+ */
+static void
+start_resolution(struct GNUNET_DNS_RequestHandle *request,
+ struct GNUNET_DNSPARSER_Packet *p,
+ struct GNUNET_DNSPARSER_Query *q)
+{
+ struct GNUNET_GNS_ResolverHandle *rh;
+
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Starting resolution for %s (type=%d)!\n",
+ q->name, q->type);
+
+ rh = GNUNET_malloc(sizeof (struct GNUNET_GNS_ResolverHandle));
+ rh->packet = p;
+ rh->query = q;
+ rh->authority = zone_hash;
+
+ rh->name = GNUNET_malloc(strlen(q->name)
+ - strlen(gnunet_tld) + 1);
+ memset(rh->name, 0,
+ strlen(q->name)-strlen(gnunet_tld) + 1);
+ memcpy(rh->name, q->name,
+ strlen(q->name)-strlen(gnunet_tld));
+
+ rh->request_handle = request;
+
+ /* Start resolution in our zone */
+ resolve_name(rh);
}
/**
* The DNS request handler
+ * Called for every incoming DNS request.
*
* @param cls closure
* @param rh request handle to user for reply
* @param request_length number of bytes in request
* @param request udp payload of the DNS request
*/
-void
+static void
handle_dns_request(void *cls,
- struct GNUNET_DNS_RequestHandle *rh,
- size_t request_length,
- const char *request)
-{
- /**
- * TODO: parse request for tld
- * Queue rh and gns handle (or use cls)
- * How should lookup behave:
- * - sync and return result or "NX"
- * - async like dht with iter
- * Maybe provide both, useful for cli app
- **/
+ struct GNUNET_DNS_RequestHandle *rh,
+ size_t request_length,
+ const char *request)
+{
struct GNUNET_DNSPARSER_Packet *p;
- char buf[INET6_ADDRSTRLEN];
- int namelen;
-
- p = GNUNET_DNSPARSER_parse (request, request_length);
- if (NULL == p)
- {
- fprintf (stderr, "Received malformed DNS packet, leaving it untouched\n");
- GNUNET_DNS_request_forward (rh);
- return;
- }
- /* TODO factor out */
- for (i=0;i<p->num_queries;i++)
- {
- namelen = strlen(&p->queries[i]->name);
- if (namelen >= 7)
- {
- if (0 == strcmp(&p->queries[i]->name, ".gnunet"))
- {
- GNUNET_DNS_request_answer(rh, 0 /*length*/, NULL/*reply*/);
- }
- else
- {
- GNUNET_DNS_request_forward (rh);
- }
- }
- }
+ char *tldoffset;
+
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Hijacked a DNS request...processing\n");
+ p = GNUNET_DNSPARSER_parse (request, request_length);
+
+ if (NULL == p)
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
+ "Received malformed DNS packet, leaving it untouched\n");
+ GNUNET_DNS_request_forward (rh);
+ return;
+ }
+
+ /**
+ * Check tld and decide if we or
+ * legacy dns is responsible
+ *
+ * FIXME now in theory there could be more than 1 query in the request
+ * but if this is case we get into trouble:
+ * either we query the GNS or the DNS. We cannot do both!
+ * So I suggest to either only allow a single query per request or
+ * only allow GNS or DNS requests.
+ * The way it is implemented here now is buggy and will lead to erratic
+ * behaviour (if multiple queries are present).
+ */
+ if (p->num_queries == 0)
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "No Queries in DNS packet... forwarding\n");
+ GNUNET_DNS_request_forward (rh);
+ }
+
+ if (p->num_queries > 1)
+ {
+ /* Note: We could also look for .gnunet */
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ ">1 queriy in DNS packet... odd. We only process #1\n");
+ }
+
+
+ /**
+ * Check for .gnunet
+ */
+ tldoffset = p->queries[0].name + strlen(p->queries[0].name);
+
+ while ((*tldoffset) != '.')
+ tldoffset--;
+
+ if (0 == strcmp(tldoffset, gnunet_tld))
+ {
+ start_resolution(rh, p, p->queries);
+ }
+ else
+ {
+ /**
+ * This request does not concern us. Forward to real DNS.
+ */
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
+ "Request for %s is forwarded to DNS\n", p->queries[0].name);
+ GNUNET_DNS_request_forward (rh);
+ }
+
+}
+
+/**
+ * Method called periodicattluy that triggers
+ * iteration over root zone
+ *
+ * @param cls closure
+ * @param tc task context
+ */
+static void
+update_zone_dht_next(void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
+{
+ GNUNET_NAMESTORE_zone_iterator_next(namestore_iter);
+}
+
+/**
+ * Continuation for DHT put
+ *
+ * @param cls closure
+ * @param tc task context
+ */
+static void
+record_dht_put(void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
+{
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "put request transmitted\n");
+}
+
+/* prototype */
+static void
+update_zone_dht_start(void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc);
+
+/**
+ * Function used to put all records successively into the DHT.
+ *
+ * @param cls the closure (NULL)
+ * @param key the public key of the authority (ours)
+ * @param expiration lifetime of the namestore entry
+ * @param name the name of the records
+ * @param rd_count the number of records in data
+ * @param rd the record data
+ * @param signature the signature for the record data
+ */
+static void
+put_gns_record(void *cls,
+ const struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded *key,
+ struct GNUNET_TIME_Absolute expiration,
+ const char *name,
+ unsigned int rd_count,
+ const struct GNUNET_NAMESTORE_RecordData *rd,
+ const struct GNUNET_CRYPTO_RsaSignature *signature)
+{
+
+ struct GNSNameRecordBlock *nrb;
+ GNUNET_HashCode name_hash;
+ GNUNET_HashCode xor_hash;
+ struct GNUNET_CRYPTO_HashAsciiEncoded xor_hash_string;
+ uint32_t rd_payload_length;
+ char* nrb_data = NULL;
+
+ /* we're done */
+ if (NULL == name)
+ {
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Zone iteration finished\n");
+ GNUNET_NAMESTORE_zone_iteration_stop (namestore_iter);
+ zone_update_taskid = GNUNET_SCHEDULER_add_now (&update_zone_dht_start,
+ NULL);
+ return;
+ }
+
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
+ "Putting records for %s into the DHT\n", name);
+
+ rd_payload_length = GNUNET_NAMESTORE_records_get_size (rd_count, rd);
+
+ nrb = GNUNET_malloc(rd_payload_length + strlen(name) + 1
+ + sizeof(struct GNSNameRecordBlock));
+
+ if (signature != NULL)
+ nrb->signature = *signature;
+
+ nrb->public_key = *key;
+
+ nrb->rd_count = htonl(rd_count);
+
+ memset(&nrb[1], 0, strlen(name) + 1);
+ memcpy(&nrb[1], name, strlen(name));
+
+ nrb_data = (char*)&nrb[1];
+ nrb_data += strlen(name) + 1;
+
+ rd_payload_length += sizeof(struct GNSNameRecordBlock) +
+ strlen(name) + 1;
+
+ if (-1 == GNUNET_NAMESTORE_records_serialize (rd_count,
+ rd,
+ rd_payload_length,
+ nrb_data))
+ {
+ GNUNET_log(GNUNET_ERROR_TYPE_ERROR, "Record serialization failed!\n");
+ return;
+ //FIXME what to do
+ }
+
+
+ /*
+ * calculate DHT key: H(name) xor H(pubkey)
+ */
+ GNUNET_CRYPTO_hash(name, strlen(name), &name_hash);
+ GNUNET_CRYPTO_hash_xor(&zone_hash, &name_hash, &xor_hash);
+ GNUNET_CRYPTO_hash_to_enc (&xor_hash, &xor_hash_string);
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
+ "putting records for %s under key: %s with size %d\n",
+ name, (char*)&xor_hash_string, rd_payload_length);
+
+ GNUNET_DHT_put (dht_handle, &xor_hash,
+ DHT_GNS_REPLICATION_LEVEL,
+ GNUNET_DHT_RO_NONE,
+ GNUNET_BLOCK_TYPE_GNS_NAMERECORD,
+ rd_payload_length,
+ (char*)nrb,
+ expiration,
+ DHT_OPERATION_TIMEOUT,
+ &record_dht_put,
+ NULL); //cls for cont
+
+ num_public_records++;
+
+ /**
+ * Reschedule periodic put
+ */
+ zone_update_taskid = GNUNET_SCHEDULER_add_delayed (dht_update_interval,
+ &update_zone_dht_next,
+ NULL);
+
}
+/**
+ * Periodically iterate over our zone and store everything in dht
+ *
+ * @param cls NULL
+ * @param tc task context
+ */
+static void
+update_zone_dht_start(void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
+{
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Starting DHT zone update!\n");
+ if (0 == num_public_records)
+ {
+ dht_update_interval = GNUNET_TIME_relative_multiply(
+ GNUNET_TIME_UNIT_SECONDS,
+ 1);
+ }
+ else
+ {
+ dht_update_interval = GNUNET_TIME_relative_multiply(
+ GNUNET_TIME_UNIT_SECONDS,
+ (3600/num_public_records));
+ }
+ num_public_records = 0; //start counting again
+ namestore_iter = GNUNET_NAMESTORE_zone_iteration_start (namestore_handle,
+ &zone_hash,
+ GNUNET_NAMESTORE_RF_AUTHORITY,
+ GNUNET_NAMESTORE_RF_PRIVATE,
+ &put_gns_record,
+ NULL);
+}
/**
* Process GNS requests.
run (void *cls, struct GNUNET_SERVER_Handle *server,
const struct GNUNET_CONFIGURATION_Handle *c)
{
- /* The IPC message types */
- static const struct GNUNET_SERVER_MessageHandler handlers[] = {
- /* callback, cls, type, size */
- {&handle_record_lookup, NULL, GNUNET_MESSAGE_TYPE_GNS_RECORD_LOOKUP,
- sizeof (struct GNUNET_GNS_Lookup)},
- {&handle_record_add, NULL, GNUNET_MESSAGE_TYPE_GNS_RECORD_ADD,
- sizeof (struct GNUNET_GNS_Record)},
- {NULL, NULL, 0, 0}
- };
-
- nc = GNUNET_SERVER_notification_context_create (server, 1);
-
- /* TODO do some config parsing */
-
- GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_FOREVER_REL, &shutdown_task,
+
+ GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Initializing GNS\n");
+
+ char* keyfile;
+ struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded pkey;
+
+ if (GNUNET_OK != GNUNET_CONFIGURATION_get_value_string (c, "gns",
+ "ZONEKEY", &keyfile))
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+ "No private key for root zone specified%s!\n", keyfile);
+ GNUNET_SCHEDULER_shutdown(0);
+ return;
+ }
+
+ zone_key = GNUNET_CRYPTO_rsa_key_create_from_file (keyfile);
+ GNUNET_CRYPTO_rsa_key_get_public (zone_key, &pkey);
+
+ GNUNET_CRYPTO_hash(&pkey, sizeof(struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded),
+ &zone_hash);
+
+ nc = GNUNET_SERVER_notification_context_create (server, 1);
+
+ GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_FOREVER_REL, &shutdown_task,
NULL);
- /**
- * Do gnunet dns init here
- * */
- dns_handle = GNUNET_DNS_connect(c,
- GNUNET_DNS_FLAG_PRE_RESOLUTION,
- &handle_dns_request, /* rh */
- NULL); /* Closure */
- GNUNET_SERVER_add_handlers (server, handlers);
- /**
- * Esp the lookup would require to keep track of the clients' context
- * See dht.
- * GNUNET_SERVER_disconnect_notify (server, &client_disconnect, NULL);
- * */
+
+ if (GNUNET_YES ==
+ GNUNET_CONFIGURATION_get_value_yesno (c, "gns",
+ "HIJACK_DNS"))
+ {
+ GNUNET_log(GNUNET_ERROR_TYPE_INFO,
+ "DNS hijacking enabled... connecting to service.\n");
+ /**
+ * Do gnunet dns init here
+ */
+ dns_handle = GNUNET_DNS_connect(c,
+ GNUNET_DNS_FLAG_PRE_RESOLUTION,
+ &handle_dns_request, /* rh */
+ NULL); /* Closure */
+ if (NULL == dns_handle)
+ {
+ GNUNET_log(GNUNET_ERROR_TYPE_ERROR,
+ "Failed to connect to the dnsservice!\n");
+ }
+ }
+
+
+
+ /**
+ * handle to our local namestore
+ */
+ namestore_handle = GNUNET_NAMESTORE_connect(c);
+
+ if (NULL == namestore_handle)
+ {
+ //FIXME do error handling;
+ GNUNET_log(GNUNET_ERROR_TYPE_ERROR,
+ "Failed to connect to the namestore!\n");
+ GNUNET_SCHEDULER_shutdown(0);
+ return;
+ }
+
+ /**
+ * handle to the dht
+ */
+ dht_handle = GNUNET_DHT_connect(c, 1); //FIXME get ht_len from cfg
+
+ if (NULL == dht_handle)
+ {
+ GNUNET_log(GNUNET_ERROR_TYPE_ERROR, "Could not connect to DHT!\n");
+ }
+
+ //put_some_records(); //FIXME for testing
+
+ /**
+ * Schedule periodic put
+ * for our records
+ * We have roughly an hour for all records;
+ */
+ dht_update_interval = GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_SECONDS,
+ 1);
+ //zone_update_taskid = GNUNET_SCHEDULER_add_now (&update_zone_dht_start, NULL);
+
}