Illegal request

/* This file is part of GNUnet. (C) 2012 Christian Grothoff (and other contributing authors) GNUnet is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3, or (at your option) any later version. GNUnet is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with GNUnet; see the file COPYING. If not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ /** * @file gnunet-gns-fcfsd.c * @brief HTTP daemon that offers first-come-first-serve GNS domain registration * @author Christian Grothoff * * TODO: * - the code currently contains a 'race' between checking that the * domain name is available and allocating it to the new public key * (should this race be solved by namestore or by fcfsd?) * - nicer error reporting to browser * - figure out where this binary should go (is gns the right directory!?) */ #include "platform.h" #include #include #include /** * Invalid method page. */ #define METHOD_ERROR "Illegal requestGo away." /** * Front page. (/) */ #define MAIN_PAGE "GNUnet FCFS Authority Name Registration Service

What is your desired domain name?

What is your public key? " /** * Second page (/S) */ #define SUBMIT_PAGE "%s%s" /** * Mime type for HTML pages. */ #define MIME_HTML "text/html" /** * Name of our cookie. */ #define COOKIE_NAME "gns-fcfs" /** * Phases a request goes through. */ enum Phase { /** * Start phase (parsing POST, checking). */ RP_START = 0, /** * Lookup to see if the domain name is taken. */ RP_LOOKUP, /** * Storing of the record. */ RP_PUT, /** * We're done with success. */ RP_SUCCESS, /** * Send failure message. */ RP_FAIL }; /** * Data kept per request. */ struct Request { /** * Associated session. */ struct Session *session; /** * Post processor handling form data (IF this is * a POST request). */ struct MHD_PostProcessor *pp; /** * URL to serve in response to this POST (if this request * was a 'POST') */ const char *post_url; /** * Active request with the namestore. */ struct GNUNET_NAMESTORE_QueueEntry *qe; /** * Current processing phase. */ enum Phase phase; /** * Domain name submitted via form. */ char domain_name[64]; /** * Public key submitted via form. */ char public_key[64]; }; /** * MHD deamon reference. */ static struct MHD_Daemon *httpd; /** * Main HTTP task. */ static GNUNET_SCHEDULER_TaskIdentifier httpd_task; /** * Handle to the namestore. */ static struct GNUNET_NAMESTORE_Handle *ns; /** * Hash of the public key of the fcfsd zone. */ static struct GNUNET_CRYPTO_ShortHashCode fcfsd_zone; /** * Private key for the fcfsd zone. */ static struct GNUNET_CRYPTO_RsaPrivateKey *fcfs_zone_pkey; /** * Handler that returns a simple static HTTP page. * * @param connection connection to use * @return MHD_YES on success */ static int serve_main_page (struct MHD_Connection *connection) { int ret; struct MHD_Response *response; /* return static form */ response = MHD_create_response_from_buffer (strlen (MAIN_PAGE), (void *) MAIN_PAGE, MHD_RESPMEM_PERSISTENT); MHD_add_response_header (response, MHD_HTTP_HEADER_CONTENT_TYPE, MIME_HTML); ret = MHD_queue_response (connection, MHD_HTTP_OK, response); MHD_destroy_response (response); return ret; } /** * Send the 'SUBMIT_PAGE'. * * @param info information string to send to the user * @param request request information * @param connection connection to use */ static int fill_s_reply (const char *info, struct Request *request, struct MHD_Connection *connection) { int ret; char *reply; struct MHD_Response *response; GNUNET_asprintf (&reply, SUBMIT_PAGE, info, info); /* return static form */ response = MHD_create_response_from_buffer (strlen (reply), (void *) reply, MHD_RESPMEM_MUST_FREE); MHD_add_response_header (response, MHD_HTTP_HEADER_CONTENT_TYPE, MIME_HTML); ret = MHD_queue_response (connection, MHD_HTTP_OK, response); MHD_destroy_response (response); return ret; } /** * Iterator over key-value pairs where the value * maybe made available in increments and/or may * not be zero-terminated. Used for processing * POST data. * * @param cls user-specified closure * @param kind type of the value * @param key 0-terminated key for the value * @param filename name of the uploaded file, NULL if not known * @param content_type mime-type of the data, NULL if not known * @param transfer_encoding encoding of the data, NULL if not known * @param data pointer to size bytes of data at the * specified offset * @param off offset of data in the overall value * @param size number of bytes in data available * @return MHD_YES to continue iterating, * MHD_NO to abort the iteration */ static int post_iterator (void *cls, enum MHD_ValueKind kind, const char *key, const char *filename, const char *content_type, const char *transfer_encoding, const char *data, uint64_t off, size_t size) { struct Request *request = cls; if (0 == strcmp ("domain", key)) { if (size + off >= sizeof(request->domain_name)) size = sizeof (request->domain_name) - off - 1; memcpy (&request->domain_name[off], data, size); request->domain_name[size+off] = '\0'; return MHD_YES; } if (0 == strcmp ("pkey", key)) { if (size + off >= sizeof(request->public_key)) size = sizeof (request->public_key) - off - 1; memcpy (&request->public_key[off], data, size); request->public_key[size+off] = '\0'; return MHD_YES; } GNUNET_log (GNUNET_ERROR_TYPE_ERROR, _("Unsupported form value `%s'\n"), key); return MHD_YES; } /** * Task run whenever HTTP server operations are pending. * * @param cls unused * @param tc scheduler context */ static void do_httpd (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc); /** * Schedule task to run MHD server now. */ static void run_httpd_now () { if (GNUNET_SCHEDULER_NO_TASK != httpd_task) { GNUNET_SCHEDULER_cancel (httpd_task); httpd_task = GNUNET_SCHEDULER_NO_TASK; } httpd_task = GNUNET_SCHEDULER_add_now (&do_httpd, NULL); } /** * Continuation called to notify client about result of the * operation. * * @param cls closure * @param success GNUNET_SYSERR on failure (including timeout/queue drop/failure to validate) * GNUNET_NO if content was already there * GNUNET_YES (or other positive value) on success * @param emsg NULL on success, otherwise an error message */ static void put_continuation (void *cls, int32_t success, const char *emsg) { struct Request *request = cls; request->qe = NULL; if (0 >= success) { GNUNET_log (GNUNET_ERROR_TYPE_WARNING, _("Failed to create record for domain `%s': %s\n"), request->domain_name, emsg); request->phase = RP_FAIL; } else request->phase = RP_SUCCESS; run_httpd_now (); } /** * Test if a name mapping was found, if so, refuse. If not, initiate storing of the record. * * @param cls closure * @param zone_key public key of the zone * @param expire when does the corresponding block in the DHT expire (until * when should we never do a DHT lookup for the same name again)?; * GNUNET_TIME_UNIT_ZERO_ABS if there are no records of any type in the namestore, * or the expiration time of the block in the namestore (even if there are zero * records matching the desired record type) * @param name name that is being mapped (at most 255 characters long) * @param rd_count number of entries in 'rd' array * @param rd array of records with data to store * @param signature signature of the record block, NULL if signature is unavailable (i.e. * because the user queried for a particular record type only) */ static void zone_to_name_cb (void *cls, const struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded *zone_key, struct GNUNET_TIME_Absolute expire, const char *name, unsigned int rd_count, const struct GNUNET_NAMESTORE_RecordData *rd, const struct GNUNET_CRYPTO_RsaSignature *signature) { struct Request *request = cls; struct GNUNET_NAMESTORE_RecordData r; struct GNUNET_CRYPTO_ShortHashCode pub; request->qe = NULL; if (NULL != name) { GNUNET_log (GNUNET_ERROR_TYPE_INFO, _("Found existing name `%s' for the given key\n"), name); request->phase = RP_FAIL; run_httpd_now (); return; } GNUNET_assert (GNUNET_OK == GNUNET_CRYPTO_short_hash_from_string2 (request->public_key, strlen (request->public_key), &pub)); r.data = &pub; r.data_size = sizeof (pub); r.expiration = GNUNET_TIME_UNIT_FOREVER_ABS; r.record_type = GNUNET_NAMESTORE_TYPE_PKEY; r.flags = GNUNET_NAMESTORE_RF_AUTHORITY; request->qe = GNUNET_NAMESTORE_record_create (ns, fcfs_zone_pkey, request->domain_name, &r, &put_continuation, request); } /** * Process a record that was stored in the namestore. Used to check if * the requested name already exists in the namestore. If not, * proceed to check if the requested key already exists. * * @param cls closure * @param zone_key public key of the zone * @param expire when does the corresponding block in the DHT expire (until * when should we never do a DHT lookup for the same name again)?; * GNUNET_TIME_UNIT_ZERO_ABS if there are no records of any type in the namestore, * or the expiration time of the block in the namestore (even if there are zero * records matching the desired record type) * @param name name that is being mapped (at most 255 characters long) * @param rd_count number of entries in 'rd' array * @param rd array of records with data to store * @param signature signature of the record block, NULL if signature is unavailable (i.e. * because the user queried for a particular record type only) */ static void lookup_result_processor (void *cls, const struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded *zone_key, struct GNUNET_TIME_Absolute expire, const char *name, unsigned int rd_count, const struct GNUNET_NAMESTORE_RecordData *rd, const struct GNUNET_CRYPTO_RsaSignature *signature) { struct Request *request = cls; struct GNUNET_CRYPTO_ShortHashCode pub; request->qe = NULL; GNUNET_assert (GNUNET_OK == GNUNET_CRYPTO_short_hash_from_string2 (request->public_key, strlen (request->public_key), &pub)); if (0 != rd_count) { GNUNET_log (GNUNET_ERROR_TYPE_INFO, _("Found %u existing records for domain `%s'\n"), rd_count, request->domain_name); request->phase = RP_FAIL; run_httpd_now (); return; } request->qe = GNUNET_NAMESTORE_zone_to_name (ns, &fcfsd_zone, &pub, &zone_to_name_cb, request); } /** * Main MHD callback for handling requests. * * @param cls unused * @param connection MHD connection handle * @param url the requested url * @param method the HTTP method used ("GET", "PUT", etc.) * @param version the HTTP version string (i.e. "HTTP/1.1") * @param upload_data the data being uploaded (excluding HEADERS, * for a POST that fits into memory and that is encoded * with a supported encoding, the POST data will NOT be * given in upload_data and is instead available as * part of MHD_get_connection_values; very large POST * data *will* be made available incrementally in * upload_data) * @param upload_data_size set initially to the size of the * upload_data provided; the method must update this * value to the number of bytes NOT processed; * @param ptr pointer to location where we store the 'struct Request' * @return MHS_YES if the connection was handled successfully, * MHS_NO if the socket must be closed due to a serios * error while handling the request */ static int create_response (void *cls, struct MHD_Connection *connection, const char *url, const char *method, const char *version, const char *upload_data, size_t *upload_data_size, void **ptr) { struct MHD_Response *response; struct Request *request; int ret; struct GNUNET_CRYPTO_ShortHashCode pub; if ( (0 == strcmp (method, MHD_HTTP_METHOD_GET)) || (0 == strcmp (method, MHD_HTTP_METHOD_HEAD)) ) { ret = serve_main_page (connection); if (ret != MHD_YES) GNUNET_log (GNUNET_ERROR_TYPE_ERROR, _("Failed to create page for `%s'\n"), url); return ret; } if (0 == strcmp (method, MHD_HTTP_METHOD_POST)) { request = *ptr; if (NULL == request) { request = GNUNET_malloc (sizeof (struct Request)); *ptr = request; request->pp = MHD_create_post_processor (connection, 1024, &post_iterator, request); if (NULL == request->pp) { GNUNET_log (GNUNET_ERROR_TYPE_ERROR, _("Failed to setup post processor for `%s'\n"), url); return MHD_NO; /* internal error */ } return MHD_YES; } if (NULL != request->pp) { /* evaluate POST data */ MHD_post_process (request->pp, upload_data, *upload_data_size); if (0 != *upload_data_size) { *upload_data_size = 0; return MHD_YES; } /* done with POST data, serve response */ MHD_destroy_post_processor (request->pp); request->pp = NULL; } if (GNUNET_OK != GNUNET_CRYPTO_short_hash_from_string2 (request->public_key, strlen (request->public_key), &pub)) { /* parse error */ return fill_s_reply ("Failed to parse given public key", request, connection); } switch (request->phase) { case RP_START: request->phase = RP_LOOKUP; request->qe = GNUNET_NAMESTORE_lookup_record (ns, &fcfsd_zone, request->domain_name, GNUNET_NAMESTORE_TYPE_PKEY, &lookup_result_processor, request); break; case RP_LOOKUP: break; case RP_PUT: break; case RP_FAIL: return fill_s_reply ("Request failed, sorry.", request, connection); case RP_SUCCESS: return fill_s_reply ("Success.", request, connection); default: GNUNET_break (0); return MHD_NO; } return MHD_YES; /* will have a reply later... */ } /* unsupported HTTP method */ response = MHD_create_response_from_buffer (strlen (METHOD_ERROR), (void *) METHOD_ERROR, MHD_RESPMEM_PERSISTENT); ret = MHD_queue_response (connection, MHD_HTTP_METHOD_NOT_ACCEPTABLE, response); MHD_destroy_response (response); return ret; } /** * Callback called upon completion of a request. * Decrements session reference counter. * * @param cls not used * @param connection connection that completed * @param con_cls session handle * @param toe status code */ static void request_completed_callback (void *cls, struct MHD_Connection *connection, void **con_cls, enum MHD_RequestTerminationCode toe) { struct Request *request = *con_cls; if (NULL == request) return; if (NULL != request->pp) MHD_destroy_post_processor (request->pp); if (NULL != request->qe) GNUNET_NAMESTORE_cancel (request->qe); GNUNET_free (request); } /** * Schedule tasks to run MHD server. */ static void run_httpd () { fd_set rs; fd_set ws; fd_set es; struct GNUNET_NETWORK_FDSet *wrs; struct GNUNET_NETWORK_FDSet *wws; struct GNUNET_NETWORK_FDSet *wes; int max; int haveto; unsigned MHD_LONG_LONG timeout; struct GNUNET_TIME_Relative tv; FD_ZERO (&rs); FD_ZERO (&ws); FD_ZERO (&es); wrs = GNUNET_NETWORK_fdset_create (); wes = GNUNET_NETWORK_fdset_create (); wws = GNUNET_NETWORK_fdset_create (); max = -1; GNUNET_assert (MHD_YES == MHD_get_fdset (httpd, &rs, &ws, &es, &max)); haveto = MHD_get_timeout (httpd, &timeout); if (haveto == MHD_YES) tv.rel_value = (uint64_t) timeout; else tv = GNUNET_TIME_UNIT_FOREVER_REL; GNUNET_NETWORK_fdset_copy_native (wrs, &rs, max + 1); GNUNET_NETWORK_fdset_copy_native (wws, &ws, max + 1); GNUNET_NETWORK_fdset_copy_native (wes, &es, max + 1); httpd_task = GNUNET_SCHEDULER_add_select (GNUNET_SCHEDULER_PRIORITY_HIGH, tv, wrs, wws, &do_httpd, NULL); GNUNET_NETWORK_fdset_destroy (wrs); GNUNET_NETWORK_fdset_destroy (wws); GNUNET_NETWORK_fdset_destroy (wes); } /** * Task run whenever HTTP server operations are pending. * * @param cls unused * @param tc scheduler context */ static void do_httpd (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc) { httpd_task = GNUNET_SCHEDULER_NO_TASK; MHD_run (httpd); run_httpd (); } /** * Task run on shutdown. Cleans up everything. * * @param cls unused * @param tc scheduler context */ static void do_shutdown (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc) { if (GNUNET_SCHEDULER_NO_TASK != httpd_task) { GNUNET_SCHEDULER_cancel (httpd_task); httpd_task = GNUNET_SCHEDULER_NO_TASK; } if (NULL != ns) { GNUNET_NAMESTORE_disconnect (ns, GNUNET_NO); ns = NULL; } if (NULL != httpd) { MHD_stop_daemon (httpd); httpd = NULL; } if (NULL != fcfs_zone_pkey) { GNUNET_CRYPTO_rsa_key_free (fcfs_zone_pkey); fcfs_zone_pkey = NULL; } } /** * Main function that will be run. * * @param cls closure * @param args remaining command-line arguments * @param cfgfile name of the configuration file used (for saving, can be NULL!) * @param cfg configuration */ static void run (void *cls, char *const *args, const char *cfgfile, const struct GNUNET_CONFIGURATION_Handle *cfg) { char *keyfile; unsigned long long port; struct GNUNET_CRYPTO_RsaPublicKeyBinaryEncoded pub; if (GNUNET_OK != GNUNET_CONFIGURATION_get_value_number (cfg, "fcfsd", "HTTPPORT", &port)) { GNUNET_log (GNUNET_ERROR_TYPE_ERROR, _("Option `%s' not specified in configuration section `%s'\n"), "HTTPPORT", "fcfsd"); return; } if (GNUNET_OK != GNUNET_CONFIGURATION_get_value_filename (cfg, "fcfsd", "ZONEKEY", &keyfile)) { GNUNET_log (GNUNET_ERROR_TYPE_ERROR, _("Option `%s' not specified in configuration section `%s'\n"), "ZONEKEY", "fcfsd"); return; } fcfs_zone_pkey = GNUNET_CRYPTO_rsa_key_create_from_file (keyfile); GNUNET_free (keyfile); if (NULL == fcfs_zone_pkey) { GNUNET_log (GNUNET_ERROR_TYPE_ERROR, _("Failed to read or create private zone key\n")); return; } GNUNET_CRYPTO_rsa_key_get_public (fcfs_zone_pkey, &pub); GNUNET_CRYPTO_short_hash (&pub, sizeof (pub), &fcfsd_zone); ns = GNUNET_NAMESTORE_connect (cfg); if (NULL == ns) { GNUNET_log (GNUNET_ERROR_TYPE_ERROR, _("Failed to connect to namestore\n")); return; } httpd = MHD_start_daemon (MHD_USE_DEBUG, (uint16_t) port, NULL, NULL, &create_response, NULL, MHD_OPTION_CONNECTION_LIMIT, (unsigned int) 128, MHD_OPTION_PER_IP_CONNECTION_LIMIT, (unsigned int) 1, MHD_OPTION_CONNECTION_TIMEOUT, (unsigned int) 16, MHD_OPTION_CONNECTION_MEMORY_LIMIT, (size_t) (4 * 1024), MHD_OPTION_NOTIFY_COMPLETED, &request_completed_callback, NULL, MHD_OPTION_END); if (NULL == httpd) { GNUNET_log (GNUNET_ERROR_TYPE_ERROR, _("Failed to start HTTP server\n")); GNUNET_NAMESTORE_disconnect (ns, GNUNET_NO); ns = NULL; return; } run_httpd (); GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_FOREVER_REL, &do_shutdown, NULL); } /** * The main function for the fcfs daemon. * * @param argc number of arguments from the command line * @param argv command line arguments * @return 0 ok, 1 on error */ int main (int argc, char *const *argv) { static const struct GNUNET_GETOPT_CommandLineOption options[] = { GNUNET_GETOPT_OPTION_END }; int ret; GNUNET_log_setup ("fcfsd", "WARNING", NULL); ret = (GNUNET_OK == GNUNET_PROGRAM_run (argc, argv, "fcfsd", _("GNUnet GNS first come first serve registration service"), options, &run, NULL)) ? 0 : 1; return ret; } /* end of gnunet-gns-fcfsd.c */