From 007b8443b0cb0d67bf8b176a1a175ad4bc37f1f3 Mon Sep 17 00:00:00 2001 From: Christian Grothoff Date: Thu, 16 Jun 2011 10:09:47 +0000 Subject: [PATCH] resolver API change --- src/include/gnunet_connection_lib.h | 4 +- src/include/gnunet_resolver_service.h | 31 +- src/transport/plugin_transport_tcp.c | 10 +- src/transport/plugin_transport_udp.c | 7 +- src/transport/plugin_transport_unix.c | 4 +- src/util/client.c | 6 +- src/util/connection.c | 3 +- src/util/gnunet-resolver.c | 3 +- src/util/program.c | 5 +- src/util/resolver_api.c | 630 +++++++++++++++++--------- 10 files changed, 445 insertions(+), 258 deletions(-) diff --git a/src/include/gnunet_connection_lib.h b/src/include/gnunet_connection_lib.h index 8d2dbb611..700fef3db 100644 --- a/src/include/gnunet_connection_lib.h +++ b/src/include/gnunet_connection_lib.h @@ -81,8 +81,8 @@ struct GNUNET_CONNECTION_Credentials */ typedef int (*GNUNET_CONNECTION_AccessCheck) (void *cls, const struct GNUNET_CONNECTION_Credentials *ucred, - const struct sockaddr * addr, - socklen_t addrlen); + const struct sockaddr * addr, + socklen_t addrlen); /** diff --git a/src/include/gnunet_resolver_service.h b/src/include/gnunet_resolver_service.h index 6ffcc9455..86269d9dd 100644 --- a/src/include/gnunet_resolver_service.h +++ b/src/include/gnunet_resolver_service.h @@ -58,11 +58,25 @@ typedef void (*GNUNET_RESOLVER_AddressCallback) (void *cls, */ struct GNUNET_RESOLVER_RequestHandle; +/** + * Create the connection to the resolver service. + * + * @param cfg configuration to use + */ +void +GNUNET_RESOLVER_connect (const struct GNUNET_CONFIGURATION_Handle *c); + + +/** + * Destroy the connection to the resolver service. + */ +void +GNUNET_RESOLVER_disconnect (void); + /** * Convert a string to one or more IP addresses. * - * @param cfg configuration to use * @param hostname the hostname to resolve * @param domain AF_INET or AF_INET6; use AF_UNSPEC for "any" * @param callback function to call with addresses @@ -71,8 +85,7 @@ struct GNUNET_RESOLVER_RequestHandle; * @return handle that can be used to cancel the request, NULL on error */ struct GNUNET_RESOLVER_RequestHandle * -GNUNET_RESOLVER_ip_get (const struct GNUNET_CONFIGURATION_Handle *cfg, - const char *hostname, +GNUNET_RESOLVER_ip_get (const char *hostname, int domain, struct GNUNET_TIME_Relative timeout, GNUNET_RESOLVER_AddressCallback callback, @@ -90,8 +103,7 @@ GNUNET_RESOLVER_ip_get (const struct GNUNET_CONFIGURATION_Handle *cfg, * @return handle that can be used to cancel the request, NULL on error */ struct GNUNET_RESOLVER_RequestHandle * -GNUNET_RESOLVER_hostname_resolve (const struct GNUNET_CONFIGURATION_Handle *cfg, - int domain, +GNUNET_RESOLVER_hostname_resolve (int domain, struct GNUNET_TIME_Relative timeout, GNUNET_RESOLVER_AddressCallback callback, void *cls); @@ -113,7 +125,7 @@ typedef void (*GNUNET_RESOLVER_HostnameCallback) (void *cls, * @return local hostname, caller must free */ char * -GNUNET_RESOLVER_local_fqdn_get ( void ); +GNUNET_RESOLVER_local_fqdn_get (void); /** @@ -129,8 +141,7 @@ GNUNET_RESOLVER_local_fqdn_get ( void ); * @return handle that can be used to cancel the request, NULL on error */ struct GNUNET_RESOLVER_RequestHandle * -GNUNET_RESOLVER_hostname_get (const struct GNUNET_CONFIGURATION_Handle *cfg, - const struct sockaddr *sa, +GNUNET_RESOLVER_hostname_get (const struct sockaddr *sa, socklen_t salen, int do_resolve, struct GNUNET_TIME_Relative timeout, @@ -144,10 +155,10 @@ GNUNET_RESOLVER_hostname_get (const struct GNUNET_CONFIGURATION_Handle *cfg, * been completed (i.e, the callback has been called to * signal timeout or the final result). * - * @param h handle of request to cancel + * @param rh handle of request to cancel */ void -GNUNET_RESOLVER_request_cancel (struct GNUNET_RESOLVER_RequestHandle *h); +GNUNET_RESOLVER_request_cancel (struct GNUNET_RESOLVER_RequestHandle *rh); #if 0 /* keep Emacsens' auto-indent happy */ diff --git a/src/transport/plugin_transport_tcp.c b/src/transport/plugin_transport_tcp.c index 11b7bc3f1..42eaeb9b2 100644 --- a/src/transport/plugin_transport_tcp.c +++ b/src/transport/plugin_transport_tcp.c @@ -1670,7 +1670,6 @@ tcp_plugin_address_pretty_printer (void *cls, GNUNET_TRANSPORT_AddressStringCallback asc, void *asc_cls) { - struct Plugin *plugin = cls; struct PrettyPrinterContext *ppc; const void *sb; size_t sbs; @@ -1715,8 +1714,7 @@ tcp_plugin_address_pretty_printer (void *cls, ppc->asc = asc; ppc->asc_cls = asc_cls; ppc->port = port; - GNUNET_RESOLVER_hostname_get (plugin->env->cfg, - sb, + GNUNET_RESOLVER_hostname_get (sb, sbs, !numeric, timeout, &append_port, ppc); } @@ -3167,16 +3165,14 @@ libgnunet_plugin_transport_tcp_init (void *cls) _("TCP transport advertises itself as being on port %llu\n"), aport); - plugin->hostname_dns = GNUNET_RESOLVER_hostname_resolve (env->cfg, - AF_UNSPEC, + plugin->hostname_dns = GNUNET_RESOLVER_hostname_resolve (AF_UNSPEC, HOSTNAME_RESOLVE_TIMEOUT, &process_hostname_ips, plugin); if (plugin->external_address != NULL) { - plugin->ext_dns = GNUNET_RESOLVER_ip_get (env->cfg, - plugin->external_address, + plugin->ext_dns = GNUNET_RESOLVER_ip_get (plugin->external_address, AF_INET, GNUNET_TIME_UNIT_MINUTES, &process_external_ip, diff --git a/src/transport/plugin_transport_udp.c b/src/transport/plugin_transport_udp.c index 8f95b9ee6..2366a2e16 100644 --- a/src/transport/plugin_transport_udp.c +++ b/src/transport/plugin_transport_udp.c @@ -2001,7 +2001,6 @@ udp_plugin_address_pretty_printer (void *cls, GNUNET_TRANSPORT_AddressStringCallback asc, void *asc_cls) { - struct Plugin *plugin = cls; struct PrettyPrinterContext *ppc; const void *sb; size_t sbs; @@ -2046,8 +2045,7 @@ udp_plugin_address_pretty_printer (void *cls, ppc->asc = asc; ppc->asc_cls = asc_cls; ppc->port = port; - GNUNET_RESOLVER_hostname_get (plugin->env->cfg, - sb, + GNUNET_RESOLVER_hostname_get (sb, sbs, !numeric, timeout, &append_port, ppc); } @@ -2358,8 +2356,7 @@ libgnunet_plugin_transport_udp_init (void *cls) GNUNET_OS_network_interfaces_list (&process_interfaces, plugin); } - plugin->hostname_dns = GNUNET_RESOLVER_hostname_resolve (env->cfg, - AF_UNSPEC, + plugin->hostname_dns = GNUNET_RESOLVER_hostname_resolve (AF_UNSPEC, HOSTNAME_RESOLVE_TIMEOUT, &process_hostname_ips, plugin); diff --git a/src/transport/plugin_transport_unix.c b/src/transport/plugin_transport_unix.c index c72de6ca6..835f01611 100644 --- a/src/transport/plugin_transport_unix.c +++ b/src/transport/plugin_transport_unix.c @@ -1062,7 +1062,6 @@ unix_plugin_address_pretty_printer (void *cls, GNUNET_TRANSPORT_AddressStringCallback asc, void *asc_cls) { - struct Plugin *plugin = cls; struct PrettyPrinterContext *ppc; const void *sb; size_t sbs; @@ -1107,8 +1106,7 @@ unix_plugin_address_pretty_printer (void *cls, ppc->asc = asc; ppc->asc_cls = asc_cls; ppc->port = port; - GNUNET_RESOLVER_hostname_get (plugin->env->cfg, - sb, + GNUNET_RESOLVER_hostname_get (sb, sbs, !numeric, timeout, &append_port, ppc); } diff --git a/src/util/client.c b/src/util/client.c index 9458cc94b..7461a0fe2 100644 --- a/src/util/client.c +++ b/src/util/client.c @@ -151,9 +151,8 @@ struct GNUNET_CLIENT_Connection /** * Our configuration. - * FIXME: why do we DUP the configuration? Avoid this! */ - struct GNUNET_CONFIGURATION_Handle *cfg; + const struct GNUNET_CONFIGURATION_Handle *cfg; /** * Name of the service we interact with. @@ -377,7 +376,7 @@ GNUNET_CLIENT_connect (const char *service_name, ret->attempts = 1; ret->sock = sock; ret->service_name = GNUNET_strdup (service_name); - ret->cfg = GNUNET_CONFIGURATION_dup (cfg); + ret->cfg = cfg; ret->back_off = GNUNET_TIME_UNIT_MILLISECONDS; return ret; } @@ -447,7 +446,6 @@ GNUNET_CLIENT_disconnect (struct GNUNET_CLIENT_Connection *sock, } GNUNET_array_grow (sock->received_buf, sock->received_size, 0); GNUNET_free (sock->service_name); - GNUNET_CONFIGURATION_destroy (sock->cfg); GNUNET_free (sock); } diff --git a/src/util/connection.c b/src/util/connection.c index dae049eeb..b28c7c3e6 100644 --- a/src/util/connection.c +++ b/src/util/connection.c @@ -901,8 +901,7 @@ GNUNET_CONNECTION_create_from_connect (const struct ret->write_buffer = GNUNET_malloc(ret->write_buffer_size); ret->port = port; ret->hostname = GNUNET_strdup (hostname); - ret->dns_active = GNUNET_RESOLVER_ip_get (cfg, - ret->hostname, + ret->dns_active = GNUNET_RESOLVER_ip_get (ret->hostname, AF_UNSPEC, GNUNET_CONNECTION_CONNECT_RETRY_TIMEOUT, &try_connect_using_address, ret); diff --git a/src/util/gnunet-resolver.c b/src/util/gnunet-resolver.c index 18ce232f2..85aedcacf 100644 --- a/src/util/gnunet-resolver.c +++ b/src/util/gnunet-resolver.c @@ -61,8 +61,7 @@ run (void *cls, { if (args[0] == NULL) return; - GNUNET_RESOLVER_ip_get (cfg, - args[0], + GNUNET_RESOLVER_ip_get (args[0], AF_UNSPEC, GET_TIMEOUT, &printer, diff --git a/src/util/program.c b/src/util/program.c index 6f8467837..8fd77637f 100644 --- a/src/util/program.c +++ b/src/util/program.c @@ -32,6 +32,7 @@ #include "gnunet_getopt_lib.h" #include "gnunet_os_lib.h" #include "gnunet_program_lib.h" +#include "gnunet_resolver_service.h" #include "gnunet_scheduler_lib.h" #include @@ -77,6 +78,7 @@ program_main (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc) { struct CommandContext *cc = cls; + GNUNET_RESOLVER_connect (cc->cfg); cc->task (cc->task_cls, cc->args, cc->cfgfile, cc->cfg); } @@ -212,7 +214,6 @@ GNUNET_PROGRAM_run (int argc, loglev, logfile)) || (GNUNET_OK != GNUNET_CONFIGURATION_load (cfg, cc.cfgfile)))) - { GNUNET_CONFIGURATION_destroy (cfg); GNUNET_free_non_null (cc.cfgfile); @@ -221,7 +222,7 @@ GNUNET_PROGRAM_run (int argc, return GNUNET_SYSERR; } GNUNET_free (allopts); - + /* run */ cc.args = &argv[ret]; GNUNET_SCHEDULER_run (&program_main, &cc); diff --git a/src/util/resolver_api.c b/src/util/resolver_api.c index 7daaaf1cc..5c0973f86 100644 --- a/src/util/resolver_api.c +++ b/src/util/resolver_api.c @@ -27,6 +27,7 @@ #include "gnunet_getopt_lib.h" #include "gnunet_os_lib.h" #include "gnunet_client_lib.h" +#include "gnunet_container_lib.h" #include "gnunet_protocols.h" #include "gnunet_resolver_service.h" #include "gnunet_server_lib.h" @@ -49,6 +50,44 @@ static const char *loopback[] = { }; +/** + * Configuration. + */ +static const struct GNUNET_CONFIGURATION_Handle *cfg; + +/** + * Our connection to the resolver service, created on-demand, but then + * persists until error or shutdown. + */ +static struct GNUNET_CLIENT_Connection *client; + +/** + * Head of DLL of requests. + */ +static struct GNUNET_RESOLVER_RequestHandle *req_head; + +/** + * Tail of DLL of requests. + */ +static struct GNUNET_RESOLVER_RequestHandle *req_tail; + +/** + * How long should we wait to reconnect? + */ +static struct GNUNET_TIME_Relative backoff; + +/** + * Task for reconnecting. + */ +static GNUNET_SCHEDULER_TaskIdentifier r_task; + +/** + * Task ID of shutdown task; only present while we have a + * connection to the resolver service. + */ +static GNUNET_SCHEDULER_TaskIdentifier s_task; + + /** * Handle to a request given to the resolver. Can be used to cancel * the request prior to the timeout or successful execution. Also @@ -57,6 +96,16 @@ static const char *loopback[] = { struct GNUNET_RESOLVER_RequestHandle { + /** + * Next entry in DLL of requests. + */ + struct GNUNET_RESOLVER_RequestHandle *next; + + /** + * Previous entry in DLL of requests. + */ + struct GNUNET_RESOLVER_RequestHandle *prev; + /** * Callback if this is an name resolution request, * otherwise NULL. @@ -74,16 +123,6 @@ struct GNUNET_RESOLVER_RequestHandle */ void *cls; - /** - * Our connection to the resolver service. - */ - struct GNUNET_CLIENT_Connection *client; - - /** - * Name of the host that we are resolving. - */ - const char *hostname; - /** * When should this request time out? */ @@ -100,10 +139,24 @@ struct GNUNET_RESOLVER_RequestHandle int domain; /** - * Length of the "struct sockaddr" that follows this - * struct (only for reverse lookup). + * Has this request been transmitted to the service? */ - socklen_t salen; + int was_transmitted; + + /** + * Did we add this request to the queue? + */ + int was_queued; + + /** + * Desired direction (IP to name or name to IP) + */ + int direction; + + /** + * Length of the data that follows this struct. + */ + size_t data_len; }; @@ -163,6 +216,45 @@ check_config (const struct GNUNET_CONFIGURATION_Handle *cfg) } +/** + * Create the connection to the resolver service. + * + * @param c configuration to use + */ +void +GNUNET_RESOLVER_connect (const struct GNUNET_CONFIGURATION_Handle *c) +{ + check_config (c); + cfg = c; +} + + +/** + * Destroy the connection to the resolver service. + */ +void +GNUNET_RESOLVER_disconnect () +{ + GNUNET_assert (NULL == req_head); + GNUNET_assert (NULL == req_tail); + if (NULL != client) + { + GNUNET_CLIENT_disconnect (client, GNUNET_NO); + client = NULL; + } + if (r_task != GNUNET_SCHEDULER_NO_TASK) + { + GNUNET_SCHEDULER_cancel (r_task); + r_task = GNUNET_SCHEDULER_NO_TASK; + } + if (s_task != GNUNET_SCHEDULER_NO_TASK) + { + GNUNET_SCHEDULER_cancel (s_task); + s_task = GNUNET_SCHEDULER_NO_TASK; + } +} + + /** * Convert IP address to string without DNS resolution. * @@ -216,76 +308,146 @@ no_resolve (const struct sockaddr *sa, socklen_t salen) /** - * Process the reply from the resolver (which is presumably - * the numeric IP address for a name resolution request). + * Adjust exponential back-off and reconnect to the service. + */ +static void +reconnect (); + + +/** + * Process pending requests to the resolver. * - * @param cls the "GNUNET_RESOLVER_RequestHandle" for which this is a reply - * @param msg reply from the resolver or NULL on error + * @param h handle to the resolver + */ +static void +process_requests (); + + +/** + * Process response with a hostname for a DNS lookup. + * + * @param cls our "struct GNUNET_RESOLVER_RequestHandle" context + * @param msg message with the hostname, NULL on error */ static void -handle_address_response (void *cls, const struct GNUNET_MessageHeader *msg) +handle_response (void *cls, + const struct GNUNET_MessageHeader *msg) { struct GNUNET_RESOLVER_RequestHandle *rh = cls; uint16_t size; + const char *hostname; const struct sockaddr *sa; socklen_t salen; if (msg == NULL) { GNUNET_log (GNUNET_ERROR_TYPE_INFO, - _("Timeout trying to resolve hostname `%s'.\n"), - rh->hostname); - rh->addr_callback (rh->cls, NULL, 0); - GNUNET_CLIENT_disconnect (rh->client, GNUNET_NO); + _("Timeout trying to resolve IP address `%s'.\n"), + GNUNET_a2s ((const void*) &rh[1], rh->data_len)); + if (rh->was_transmitted != GNUNET_SYSERR) + { + if (NULL != rh->name_callback) + rh->name_callback (rh->cls, NULL); + if (NULL != rh->addr_callback) + rh->addr_callback (rh->cls, NULL, 0); + } + GNUNET_CONTAINER_DLL_remove (req_head, + req_tail, + rh); GNUNET_free (rh); + GNUNET_CLIENT_disconnect (client, GNUNET_NO); + client = NULL; + reconnect (); return; } if (GNUNET_MESSAGE_TYPE_RESOLVER_RESPONSE != ntohs (msg->type)) { GNUNET_break (0); - rh->addr_callback (rh->cls, NULL, 0); - GNUNET_CLIENT_disconnect (rh->client, GNUNET_NO); - GNUNET_free (rh); + GNUNET_CLIENT_disconnect (client, GNUNET_NO); + client = NULL; + reconnect (); return; } - size = ntohs (msg->size); if (size == sizeof (struct GNUNET_MessageHeader)) { -#if DEBUG_RESOLVER - GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, - _("Received end message resolving hostname `%s'.\n"), - rh->hostname); -#endif - rh->addr_callback (rh->cls, NULL, 0); - GNUNET_CLIENT_disconnect (rh->client, GNUNET_NO); + if (rh->was_transmitted != GNUNET_SYSERR) + { + if (NULL != rh->name_callback) + rh->name_callback (rh->cls, NULL); + if (NULL != rh->addr_callback) + rh->addr_callback (rh->cls, NULL, 0); + } + GNUNET_CONTAINER_DLL_remove (req_head, + req_tail, + rh); GNUNET_free (rh); + process_requests (); return; } - sa = (const struct sockaddr *) &msg[1]; - salen = size - sizeof (struct GNUNET_MessageHeader); - if (salen < sizeof (struct sockaddr)) + if (NULL != rh->name_callback) { - GNUNET_break (0); - rh->addr_callback (rh->cls, NULL, 0); - GNUNET_CLIENT_disconnect (rh->client, GNUNET_NO); - GNUNET_free (rh); - return; + hostname = (const char *) &msg[1]; + if (hostname[size - sizeof (struct GNUNET_MessageHeader) - 1] != '\0') + { + GNUNET_break (0); + if (rh->was_transmitted != GNUNET_SYSERR) + rh->name_callback (rh->cls, NULL); + GNUNET_CONTAINER_DLL_remove (req_head, + req_tail, + rh); + GNUNET_free (rh); + GNUNET_CLIENT_disconnect (client, GNUNET_NO); + client = NULL; + reconnect (); + return; + } +#if DEBUG_RESOLVER + GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, + _("Resolver returns `%s' for IP `%s'.\n"), + hostname, + GNUNET_a2s ((const void*) &rh[1], rh->data_len)); +#endif + if (rh->was_transmitted != GNUNET_SYSERR) + rh->name_callback (rh->cls, hostname); + GNUNET_CLIENT_receive (client, + &handle_response, + rh, + GNUNET_TIME_absolute_get_remaining (rh->timeout)); } + if (NULL != rh->addr_callback) + { + sa = (const struct sockaddr *) &msg[1]; + salen = size - sizeof (struct GNUNET_MessageHeader); + if (salen < sizeof (struct sockaddr)) + { + GNUNET_break (0); + if (rh->was_transmitted != GNUNET_SYSERR) + rh->addr_callback (rh->cls, NULL, 0); + GNUNET_CONTAINER_DLL_remove (req_head, + req_tail, + rh); + GNUNET_free (rh); + GNUNET_CLIENT_disconnect (client, GNUNET_NO); + client = NULL; + reconnect (); + return; + } #if DEBUG_RESOLVER - { - char *ips = no_resolve (sa, salen); - GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, - "Resolver returns `%s' for `%s'.\n", ips, - rh->hostname); - GNUNET_free (ips); - } + { + char *ips = no_resolve (sa, salen); + GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, + "Resolver returns `%s' for `%s'.\n", ips, + rh->hostname); + GNUNET_free (ips); + } #endif - rh->addr_callback (rh->cls, sa, salen); - GNUNET_CLIENT_receive (rh->client, - &handle_address_response, - rh, - GNUNET_TIME_absolute_get_remaining (rh->timeout)); + rh->addr_callback (rh->cls, sa, salen); + GNUNET_CLIENT_receive (client, + &handle_response, + rh, + GNUNET_TIME_absolute_get_remaining (rh->timeout)); + } } @@ -303,6 +465,7 @@ numeric_resolution (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc) struct GNUNET_RESOLVER_RequestHandle *rh = cls; struct sockaddr_in v4; struct sockaddr_in6 v6; + const char *hostname; memset (&v4, 0, sizeof (v4)); v4.sin_family = AF_INET; @@ -314,13 +477,13 @@ numeric_resolution (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc) #if HAVE_SOCKADDR_IN_SIN_LEN v6.sin6_len = sizeof (v6); #endif - + hostname = (const char*) &rh[1]; if (((rh->domain == AF_UNSPEC) || (rh->domain == AF_INET)) && - (1 == inet_pton (AF_INET, rh->hostname, &v4.sin_addr))) + (1 == inet_pton (AF_INET, hostname, &v4.sin_addr))) { rh->addr_callback (rh->cls, (const struct sockaddr *) &v4, sizeof (v4)); if ((rh->domain == AF_UNSPEC) && - (1 == inet_pton (AF_INET6, rh->hostname, &v6.sin6_addr))) + (1 == inet_pton (AF_INET6, hostname, &v6.sin6_addr))) { /* this can happen on some systems IF "hostname" is "localhost" */ rh->addr_callback (rh->cls, @@ -331,7 +494,7 @@ numeric_resolution (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc) return; } if (((rh->domain == AF_UNSPEC) || (rh->domain == AF_INET6)) && - (1 == inet_pton (AF_INET6, rh->hostname, &v6.sin6_addr))) + (1 == inet_pton (AF_INET6, hostname, &v6.sin6_addr))) { rh->addr_callback (rh->cls, (const struct sockaddr *) &v6, sizeof (v6)); rh->addr_callback (rh->cls, NULL, 0); @@ -344,7 +507,6 @@ numeric_resolution (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc) } - /** * We've been asked to lookup the address for a hostname and were * given a variant of "loopback". Perform the callbacks for the @@ -393,10 +555,139 @@ loopback_resolution (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc) } +/** + * Task executed on system shutdown. + */ +static void +shutdown_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc) +{ + s_task = GNUNET_SCHEDULER_NO_TASK; + GNUNET_RESOLVER_disconnect (); +} + + +/** + * Process pending requests to the resolver. + * + * @param h handle to the resolver + */ +static void +process_requests () +{ + struct GNUNET_RESOLVER_GetMessage *msg; + char buf[GNUNET_SERVER_MAX_MESSAGE_SIZE - 1]; + struct GNUNET_RESOLVER_RequestHandle *rh; + + if (NULL == client) + { + reconnect (); + return; + } + rh = req_head; + if (NULL == rh) + { + /* nothing to do, release socket really soon if there is nothing + else happening... */ + s_task = GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_MILLISECONDS, + &shutdown_task, NULL); + return; + } + if (GNUNET_YES == rh->was_transmitted) + return; /* waiting for reply */ + msg = (struct GNUNET_RESOLVER_GetMessage *) buf; + msg->header.size = + htons (sizeof (struct GNUNET_RESOLVER_GetMessage) + rh->data_len); + msg->header.type = htons (GNUNET_MESSAGE_TYPE_RESOLVER_REQUEST); + msg->direction = htonl (rh->direction); + msg->domain = htonl (rh->domain); + memcpy (&msg[1], &rh[1], rh->data_len); + + if (GNUNET_OK != + GNUNET_CLIENT_transmit_and_get_response (client, + &msg->header, + GNUNET_TIME_absolute_get_remaining (rh->timeout), + GNUNET_YES, + &handle_response, rh)) + { + GNUNET_CLIENT_disconnect (client, GNUNET_NO); + client = NULL; + reconnect (); + return; + } + rh->was_transmitted = GNUNET_YES; +} + + +/** + * Now try to reconnect to the resolver service. + * + * @param cls NULL + * @param tc scheduler context + */ +static void +reconnect_task (void *cls, + const struct GNUNET_SCHEDULER_TaskContext *tc) +{ + r_task = GNUNET_SCHEDULER_NO_TASK; + if (NULL == req_head) + return; /* no work pending */ + if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN)) + return; + client = GNUNET_CLIENT_connect ("resolver", cfg); + if (NULL == client) + { + reconnect (); + return; + } + process_requests (); +} + + +/** + * Adjust exponential back-off and reconnect to the service. + */ +static void +reconnect () +{ + struct GNUNET_RESOLVER_RequestHandle *rh; + + if (GNUNET_SCHEDULER_NO_TASK != r_task) + return; + GNUNET_assert (NULL == client); + if (NULL != (rh = req_head)) + { + switch (rh->was_transmitted) + { + case GNUNET_NO: + /* nothing more to do */ + break; + case GNUNET_YES: + /* disconnected, transmit again! */ + rh->was_transmitted = GNUNET_NO; + break; + case GNUNET_SYSERR: + /* request was cancelled, remove entirely */ + GNUNET_CONTAINER_DLL_remove (req_head, + req_tail, + rh); + GNUNET_free (rh); + break; + default: + GNUNET_assert (0); + break; + } + } + r_task = GNUNET_SCHEDULER_add_delayed (backoff, + &reconnect_task, + NULL); + backoff = GNUNET_TIME_relative_max (GNUNET_TIME_UNIT_SECONDS, + GNUNET_TIME_relative_multiply (backoff, 2)); +} + + /** * Convert a string to one or more IP addresses. * - * @param cfg configuration to use * @param hostname the hostname to resolve * @param domain AF_INET or AF_INET6; use AF_UNSPEC for "any" * @param callback function to call with addresses @@ -405,23 +696,18 @@ loopback_resolution (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc) * @return handle that can be used to cancel the request, NULL on error */ struct GNUNET_RESOLVER_RequestHandle * -GNUNET_RESOLVER_ip_get (const struct GNUNET_CONFIGURATION_Handle *cfg, - const char *hostname, +GNUNET_RESOLVER_ip_get (const char *hostname, int domain, struct GNUNET_TIME_Relative timeout, GNUNET_RESOLVER_AddressCallback callback, void *callback_cls) { - struct GNUNET_CLIENT_Connection *client; - struct GNUNET_RESOLVER_GetMessage *msg; struct GNUNET_RESOLVER_RequestHandle *rh; size_t slen; unsigned int i; struct in_addr v4; struct in6_addr v6; - char buf[GNUNET_SERVER_MAX_MESSAGE_SIZE - 1]; - check_config (cfg); slen = strlen (hostname) + 1; if (slen + sizeof (struct GNUNET_RESOLVER_GetMessage) >= GNUNET_SERVER_MAX_MESSAGE_SIZE) { @@ -433,9 +719,9 @@ GNUNET_RESOLVER_ip_get (const struct GNUNET_CONFIGURATION_Handle *cfg, rh->addr_callback = callback; rh->cls = callback_cls; memcpy (&rh[1], hostname, slen); - rh->hostname = (const char *) &rh[1]; + rh->data_len = slen; rh->timeout = GNUNET_TIME_relative_to_absolute (timeout); - + rh->direction = GNUNET_NO; /* first, check if this is a numeric address */ if (((1 == inet_pton (AF_INET, hostname, @@ -457,103 +743,20 @@ GNUNET_RESOLVER_ip_get (const struct GNUNET_CONFIGURATION_Handle *cfg, rh->task = GNUNET_SCHEDULER_add_now (&loopback_resolution, rh); return rh; } - - client = GNUNET_CLIENT_connect ("resolver", cfg); - if (client == NULL) - { - GNUNET_free (rh); - return NULL; - } - rh->client = client; - - msg = (struct GNUNET_RESOLVER_GetMessage *) buf; - msg->header.size = - htons (sizeof (struct GNUNET_RESOLVER_GetMessage) + slen); - msg->header.type = htons (GNUNET_MESSAGE_TYPE_RESOLVER_REQUEST); - msg->direction = htonl (GNUNET_NO); - msg->domain = htonl (domain); - memcpy (&msg[1], hostname, slen); - -#if DEBUG_RESOLVER - GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, - _("Resolver requests DNS resolution of hostname `%s'.\n"), - hostname); -#endif - if (GNUNET_OK != - GNUNET_CLIENT_transmit_and_get_response (client, - &msg->header, - timeout, - GNUNET_YES, - &handle_address_response, rh)) + GNUNET_CONTAINER_DLL_insert_tail (req_head, + req_tail, + rh); + rh->was_queued = GNUNET_YES; + if (s_task != GNUNET_SCHEDULER_NO_TASK) { - GNUNET_free (rh); - GNUNET_CLIENT_disconnect (client, GNUNET_NO); - return NULL; + GNUNET_SCHEDULER_cancel (s_task); + s_task = GNUNET_SCHEDULER_NO_TASK; } + process_requests (); return rh; } -/** - * Process response with a hostname for a reverse DNS lookup. - * - * @param cls our "struct GNUNET_RESOLVER_RequestHandle" context - * @param msg message with the hostname, NULL on error - */ -static void -handle_hostname_response (void *cls, const struct GNUNET_MessageHeader *msg) -{ - struct GNUNET_RESOLVER_RequestHandle *rh = cls; - uint16_t size; - const char *hostname; - - if (msg == NULL) - { - GNUNET_log (GNUNET_ERROR_TYPE_INFO, - _("Timeout trying to resolve IP address `%s'.\n"), - GNUNET_a2s ((const void*) &rh[1], rh->salen)); - rh->name_callback (rh->cls, NULL); - GNUNET_CLIENT_disconnect (rh->client, GNUNET_NO); - GNUNET_free (rh); - return; - } - size = ntohs (msg->size); - if (size == sizeof (struct GNUNET_MessageHeader)) - { -#if DEBUG_RESOLVER - GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, - _("Received end message resolving IP address `%s'.\n"), - GNUNET_a2s ((const void*) &rh[1], rh->salen)); -#endif - rh->name_callback (rh->cls, NULL); - GNUNET_CLIENT_disconnect (rh->client, GNUNET_NO); - GNUNET_free (rh); - return; - } - hostname = (const char *) &msg[1]; - if (hostname[size - sizeof (struct GNUNET_MessageHeader) - 1] != '\0') - { - GNUNET_break (0); - rh->name_callback (rh->cls, NULL); - GNUNET_CLIENT_disconnect (rh->client, GNUNET_NO); - GNUNET_free (rh); - return; - } -#if DEBUG_RESOLVER - GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, - _("Resolver returns `%s' for IP `%s'.\n"), - hostname, - GNUNET_a2s ((const void*) &rh[1], rh->salen)); -#endif - rh->name_callback (rh->cls, hostname); - GNUNET_CLIENT_receive (rh->client, - &handle_hostname_response, - rh, - GNUNET_TIME_absolute_get_remaining (rh->timeout)); -} - - - /** * We've been asked to convert an address to a string without * a reverse lookup. Do it. @@ -562,12 +765,13 @@ handle_hostname_response (void *cls, const struct GNUNET_MessageHeader *msg) * @param tc unused scheduler context */ static void -numeric_reverse (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc) +numeric_reverse (void *cls, + const struct GNUNET_SCHEDULER_TaskContext *tc) { struct GNUNET_RESOLVER_RequestHandle *rh = cls; char *result; - result = no_resolve ((const struct sockaddr *) &rh[1], rh->salen); + result = no_resolve ((const struct sockaddr *) &rh[1], rh->data_len); #if DEBUG_RESOLVER GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, _("Resolver returns `%s'.\n"), result); #endif @@ -581,11 +785,9 @@ numeric_reverse (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc) } - /** * Get an IP address as a string. * - * @param cfg configuration to use * @param sa host address * @param salen length of host address * @param do_resolve use GNUNET_NO to return numeric hostname @@ -595,27 +797,23 @@ numeric_reverse (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc) * @return handle that can be used to cancel the request */ struct GNUNET_RESOLVER_RequestHandle * -GNUNET_RESOLVER_hostname_get (const struct GNUNET_CONFIGURATION_Handle *cfg, - const struct sockaddr *sa, +GNUNET_RESOLVER_hostname_get (const struct sockaddr *sa, socklen_t salen, int do_resolve, struct GNUNET_TIME_Relative timeout, GNUNET_RESOLVER_HostnameCallback callback, void *cls) { - struct GNUNET_CLIENT_Connection *client; - struct GNUNET_RESOLVER_GetMessage *msg; struct GNUNET_RESOLVER_RequestHandle *rh; - char buf[GNUNET_SERVER_MAX_MESSAGE_SIZE - 1]; check_config (cfg); rh = GNUNET_malloc (sizeof (struct GNUNET_RESOLVER_RequestHandle) + salen); rh->name_callback = callback; rh->cls = cls; rh->timeout = GNUNET_TIME_relative_to_absolute (timeout); - rh->salen = salen; memcpy (&rh[1], sa, salen); - + rh->data_len = salen; + rh->direction = GNUNET_YES; if (GNUNET_NO == do_resolve) { rh->task = GNUNET_SCHEDULER_add_now (&numeric_reverse, rh); @@ -627,51 +825,31 @@ GNUNET_RESOLVER_hostname_get (const struct GNUNET_CONFIGURATION_Handle *cfg, GNUNET_free (rh); return NULL; } - client = GNUNET_CLIENT_connect ("resolver", cfg); - if (client == NULL) + GNUNET_CONTAINER_DLL_insert_tail (req_head, + req_tail, + rh); + rh->was_queued = GNUNET_YES; + if (s_task != GNUNET_SCHEDULER_NO_TASK) { - GNUNET_free (rh); - return NULL; - } - rh->client = client; - - msg = (struct GNUNET_RESOLVER_GetMessage *) buf; - msg->header.size = - htons (sizeof (struct GNUNET_RESOLVER_GetMessage) + salen); - msg->header.type = htons (GNUNET_MESSAGE_TYPE_RESOLVER_REQUEST); - msg->direction = htonl (GNUNET_YES); - msg->domain = htonl (sa->sa_family); - memcpy (&msg[1], sa, salen); -#if DEBUG_RESOLVER - GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, - _("Resolver requests DNS resolution of IP address.\n")); -#endif - if (GNUNET_OK != - GNUNET_CLIENT_transmit_and_get_response (client, - &msg->header, - timeout, - GNUNET_YES, - &handle_hostname_response, rh)) - { - GNUNET_CLIENT_disconnect (client, GNUNET_NO); - GNUNET_free (rh); - return NULL; + GNUNET_SCHEDULER_cancel (s_task); + s_task = GNUNET_SCHEDULER_NO_TASK; } + process_requests (); return rh; } /** * Get local fully qualified domain name + * * @return fqdn */ char * -GNUNET_RESOLVER_local_fqdn_get ( void ) +GNUNET_RESOLVER_local_fqdn_get () { struct hostent *host; char hostname[GNUNET_OS_get_hostname_max_length() + 1]; - if (0 != gethostname (hostname, sizeof (hostname) - 1)) { GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR | @@ -682,21 +860,21 @@ GNUNET_RESOLVER_local_fqdn_get ( void ) GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, _("Resolving our FQDN `%s'\n"), hostname); #endif - host = gethostbyname ( hostname ); - if ( NULL == host) - { - GNUNET_log (GNUNET_ERROR_TYPE_ERROR, - _("Could not resolve our FQDN : %s\n"), - hstrerror (h_errno)); - return NULL; - } + host = gethostbyname (hostname); + if (NULL == host) + { + GNUNET_log (GNUNET_ERROR_TYPE_ERROR, + _("Could not resolve our FQDN : %s\n"), + hstrerror (h_errno)); + return NULL; + } return GNUNET_strdup (host->h_name); } + /** * Looking our own hostname. * - * @param cfg configuration to use * @param domain AF_INET or AF_INET6; use AF_UNSPEC for "any" * @param callback function to call with addresses * @param cls closure for callback @@ -704,15 +882,13 @@ GNUNET_RESOLVER_local_fqdn_get ( void ) * @return handle that can be used to cancel the request, NULL on error */ struct GNUNET_RESOLVER_RequestHandle * -GNUNET_RESOLVER_hostname_resolve (const struct GNUNET_CONFIGURATION_Handle - *cfg, int domain, +GNUNET_RESOLVER_hostname_resolve (int domain, struct GNUNET_TIME_Relative timeout, GNUNET_RESOLVER_AddressCallback callback, void *cls) { char hostname[GNUNET_OS_get_hostname_max_length() + 1]; - check_config (cfg); if (0 != gethostname (hostname, sizeof (hostname) - 1)) { GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR | @@ -723,8 +899,10 @@ GNUNET_RESOLVER_hostname_resolve (const struct GNUNET_CONFIGURATION_Handle GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, _("Resolving our hostname `%s'\n"), hostname); #endif - return GNUNET_RESOLVER_ip_get (cfg, hostname, domain, timeout, callback, - cls); + return GNUNET_RESOLVER_ip_get (hostname, + domain, + timeout, + callback, cls); } @@ -734,18 +912,28 @@ GNUNET_RESOLVER_hostname_resolve (const struct GNUNET_CONFIGURATION_Handle * been completed (i.e, the callback has been called to * signal timeout or the final result). * - * @param h handle of request to cancel + * @param rh handle of request to cancel */ void -GNUNET_RESOLVER_request_cancel (struct GNUNET_RESOLVER_RequestHandle *h) +GNUNET_RESOLVER_request_cancel (struct GNUNET_RESOLVER_RequestHandle *rh) { - if (h->client != NULL) - GNUNET_CLIENT_disconnect (h->client, GNUNET_NO); - if (h->task != GNUNET_SCHEDULER_NO_TASK) - GNUNET_SCHEDULER_cancel (h->task); - GNUNET_free (h); + if (rh->task != GNUNET_SCHEDULER_NO_TASK) + { + GNUNET_SCHEDULER_cancel (rh->task); + rh->task = GNUNET_SCHEDULER_NO_TASK; + } + if (rh->was_transmitted == GNUNET_NO) + { + if (rh->was_queued == GNUNET_YES) + GNUNET_CONTAINER_DLL_remove (req_head, + req_tail, + rh); + GNUNET_free (rh); + return; + } + GNUNET_assert (rh->was_transmitted == GNUNET_YES); + rh->was_transmitted = GNUNET_SYSERR; /* mark as cancelled */ } - /* end of resolver_api.c */ -- 2.25.1