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|
/*
This file is part of TALER
Copyright (C) 2014-2020 Taler Systems SA
TALER is free software; you can redistribute it and/or modify it under the
terms of the GNU Affero General Public License as published by the Free Software
Foundation; either version 3, or (at your option) any later version.
TALER 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 Affero General Public License for more details.
You should have received a copy of the GNU Affero General Public License along with
TALER; see the file COPYING. If not, see <http://www.gnu.org/licenses/>
*/
/**
* @file taler-exchange-httpd.c
* @brief Serve the HTTP interface of the exchange
* @author Florian Dold
* @author Benedikt Mueller
* @author Christian Grothoff
*/
#include "platform.h"
#include <gnunet/gnunet_util_lib.h>
#include <jansson.h>
#include <microhttpd.h>
#include <pthread.h>
#include <sys/resource.h>
#include "taler_mhd_lib.h"
#include "taler-exchange-httpd_mhd.h"
#include "taler-exchange-httpd_deposit.h"
#include "taler-exchange-httpd_refund.h"
#include "taler-exchange-httpd_reserves_get.h"
#include "taler-exchange-httpd_withdraw.h"
#include "taler-exchange-httpd_recoup.h"
#include "taler-exchange-httpd_link.h"
#include "taler-exchange-httpd_melt.h"
#include "taler-exchange-httpd_refreshes_reveal.h"
#include "taler-exchange-httpd_terms.h"
#include "taler-exchange-httpd_transfers_get.h"
#include "taler-exchange-httpd_deposits_get.h"
#include "taler-exchange-httpd_keystate.h"
#include "taler-exchange-httpd_wire.h"
#include "taler_exchangedb_plugin.h"
#include <gnunet/gnunet_mhd_compat.h>
/**
* Backlog for listen operation on unix domain sockets.
*/
#define UNIX_BACKLOG 500
/**
* Type of the closure associated with each HTTP request to the exchange.
*/
struct ExchangeHttpRequestClosure
{
/**
* Async Scope ID associated with this request.
*/
struct GNUNET_AsyncScopeId async_scope_id;
/**
* Opaque parsing context.
*/
void *opaque_post_parsing_context;
/**
* Cached request handler for this request (once we have found one).
*/
struct TEH_RequestHandler *rh;
};
/**
* Base directory of the exchange (global)
*/
char *TEH_exchange_directory;
/**
* Directory where revocations are stored (global)
*/
char *TEH_revocation_directory;
/**
* Are clients allowed to request /keys for times other than the
* current time? Allowing this could be abused in a DoS-attack
* as building new /keys responses is expensive. Should only be
* enabled for testcases, development and test systems.
*/
int TEH_allow_keys_timetravel;
/**
* The exchange's configuration (global)
*/
struct GNUNET_CONFIGURATION_Handle *TEH_cfg;
/**
* How long is caching /keys allowed at most? (global)
*/
struct GNUNET_TIME_Relative TEH_max_keys_caching;
/**
* Master public key (according to the
* configuration in the exchange directory). (global)
*/
struct TALER_MasterPublicKeyP TEH_master_public_key;
/**
* Our DB plugin. (global)
*/
struct TALER_EXCHANGEDB_Plugin *TEH_plugin;
/**
* Default timeout in seconds for HTTP requests.
*/
static unsigned int connection_timeout = 30;
/**
* The HTTP Daemon.
*/
static struct MHD_Daemon *mhd;
/**
* Port to run the daemon on.
*/
static uint16_t serve_port;
/**
* Path for the unix domain-socket
* to run the daemon on.
*/
static char *serve_unixpath;
/**
* File mode for unix-domain socket.
*/
static mode_t unixpath_mode;
/**
* Counter for the number of requests this HTTP has processed so far.
*/
static unsigned long long req_count;
/**
* Limit for the number of requests this HTTP may process before restarting.
* (This was added as one way of dealing with unavoidable memory fragmentation
* happening slowly over time.)
*/
static unsigned long long req_max;
/**
* Signature of functions that handle operations on coins.
*
* @param connection the MHD connection to handle
* @param coin_pub the public key of the coin
* @param root uploaded JSON data
* @return MHD result code
*/
typedef MHD_RESULT
(*CoinOpHandler)(struct MHD_Connection *connection,
const struct TALER_CoinSpendPublicKeyP *coin_pub,
const json_t *root);
/**
* Handle a "/coins/$COIN_PUB/$OP" POST request. Parses the "coin_pub"
* EdDSA key of the coin and demultiplexes based on $OP.
*
* @param rh context of the handler
* @param connection the MHD connection to handle
* @param root uploaded JSON data
* @param args array of additional options (first must be the
* reserve public key, the second one should be "withdraw")
* @return MHD result code
*/
static MHD_RESULT
handle_post_coins (const struct TEH_RequestHandler *rh,
struct MHD_Connection *connection,
const json_t *root,
const char *const args[2])
{
struct TALER_CoinSpendPublicKeyP coin_pub;
static const struct
{
/**
* Name of the operation (args[1])
*/
const char *op;
/**
* Function to call to perform the operation.
*/
CoinOpHandler handler;
} h[] = {
{
.op = "deposit",
.handler = &TEH_handler_deposit
},
{
.op = "melt",
.handler = &TEH_handler_melt
},
{
.op = "recoup",
.handler = &TEH_handler_recoup
},
{
.op = "refund",
.handler = &TEH_handler_refund
},
{
.op = NULL,
.handler = NULL
},
};
(void) rh;
if (GNUNET_OK !=
GNUNET_STRINGS_string_to_data (args[0],
strlen (args[0]),
&coin_pub,
sizeof (coin_pub)))
{
GNUNET_break_op (0);
return TALER_MHD_reply_with_error (connection,
MHD_HTTP_BAD_REQUEST,
TALER_EC_COINS_INVALID_COIN_PUB,
"coin public key malformed");
}
for (unsigned int i = 0; NULL != h[i].op; i++)
if (0 == strcmp (h[i].op,
args[1]))
return h[i].handler (connection,
&coin_pub,
root);
return TALER_MHD_reply_with_error (connection,
MHD_HTTP_NOT_FOUND,
TALER_EC_OPERATION_INVALID,
"requested operation on coin unknown");
}
/**
* Function called whenever MHD is done with a request. If the
* request was a POST, we may have stored a `struct Buffer *` in the
* @a con_cls that might still need to be cleaned up. Call the
* respective function to free the memory.
*
* @param cls client-defined closure
* @param connection connection handle
* @param con_cls value as set by the last call to
* the #MHD_AccessHandlerCallback
* @param toe reason for request termination
* @see #MHD_OPTION_NOTIFY_COMPLETED
* @ingroup request
*/
static void
handle_mhd_completion_callback (void *cls,
struct MHD_Connection *connection,
void **con_cls,
enum MHD_RequestTerminationCode toe)
{
struct ExchangeHttpRequestClosure *ecls = *con_cls;
(void) cls;
(void) connection;
(void) toe;
GNUNET_log (GNUNET_ERROR_TYPE_INFO,
"Request completed\n");
if (NULL == ecls)
return;
TALER_MHD_parse_post_cleanup_callback (ecls->opaque_post_parsing_context);
GNUNET_free (ecls);
*con_cls = NULL;
/* Sanity-check that we didn't leave any transactions hanging */
/* NOTE: In high-performance production, we could consider
removing this as it should not be needed and might be costly
(to be benchmarked). */
TEH_plugin->preflight (TEH_plugin->cls,
TEH_plugin->get_session (TEH_plugin->cls));
}
/**
* We found @a rh responsible for handling a request. Parse the
* @a upload_data (if applicable) and the @a url and call the
* handler.
*
* @param rh request handler to call
* @param connection connection being handled
* @param url rest of the URL to parse
* @param inner_cls closure for the handler, if needed
* @param upload_data upload data to parse (if available)
* @param[in,out] upload_data_size number of bytes in @a upload_data
* @return MHD result code
*/
static MHD_RESULT
proceed_with_handler (const struct TEH_RequestHandler *rh,
struct MHD_Connection *connection,
const char *url,
void **inner_cls,
const char *upload_data,
size_t *upload_data_size)
{
const char *args[rh->nargs + 1];
size_t ulen = strlen (url) + 1;
json_t *root = NULL;
MHD_RESULT ret;
/* We do check for "ulen" here, because we'll later stack-allocate a buffer
of that size and don't want to enable malicious clients to cause us
huge stack allocations. */
if (ulen > 512)
{
/* 512 is simply "big enough", as it is bigger than "6 * 54",
which is the longest URL format we ever get (for
/deposits/). The value should be adjusted if we ever define protocol
endpoints with plausibly longer inputs. */
GNUNET_break_op (0);
return TALER_MHD_reply_with_error (connection,
MHD_HTTP_URI_TOO_LONG,
TALER_EC_URI_TOO_LONG,
"The URI given is too long");
}
/* All POST endpoints come with a body in JSON format. So we parse
the JSON here. */
if (0 == strcasecmp (rh->method,
MHD_HTTP_METHOD_POST))
{
enum GNUNET_GenericReturnValue res;
res = TALER_MHD_parse_post_json (connection,
inner_cls,
upload_data,
upload_data_size,
&root);
if (GNUNET_SYSERR == res)
{
GNUNET_assert (NULL == root);
return MHD_NO; /* bad upload, could not even generate error */
}
if ( (GNUNET_NO == res) || (NULL == root) )
{
GNUNET_assert (NULL == root);
return MHD_YES; /* so far incomplete upload or parser error */
}
}
{
char d[ulen];
/* Parse command-line arguments, if applicable */
if (rh->nargs > 0)
{
unsigned int i;
const char *fin;
char *sp;
/* make a copy of 'url' because 'strtok_r()' will modify */
memcpy (d,
url,
ulen);
i = 0;
args[i++] = strtok_r (d, "/", &sp);
while ( (NULL != args[i - 1]) &&
(i < rh->nargs) )
args[i++] = strtok_r (NULL, "/", &sp);
/* make sure above loop ran nicely until completion, and also
that there is no excess data in 'd' afterwards */
if ( (i != rh->nargs) ||
(NULL == args[i - 1]) ||
(NULL != (fin = strtok_r (NULL, "/", &sp))) )
{
char emsg[128 + 512];
GNUNET_snprintf (emsg,
sizeof (emsg),
"Got %u/%u segments for %s request ('%s')",
(NULL == args[i - 1])
? i - 1
: i + ((NULL != fin) ? 1 : 0),
rh->nargs,
rh->url,
url);
GNUNET_break_op (0);
if (NULL != root)
json_decref (root);
return TALER_MHD_reply_with_error (connection,
MHD_HTTP_NOT_FOUND,
TALER_EC_WRONG_NUMBER_OF_SEGMENTS,
emsg);
}
}
/* just to be safe(r), we always terminate the array with a NULL
(which handlers should not read, but at least if they do, they'll
crash pretty reliably...) */
args[rh->nargs] = NULL;
/* Above logic ensures that 'root' is exactly non-NULL for POST operations,
so we test for 'root' to decide which handler to invoke. */
if (NULL != root)
ret = rh->handler.post (rh,
connection,
root,
args);
else /* We also only have "POST" or "GET" in the API for at this point
(OPTIONS/HEAD are taken care of earlier) */
ret = rh->handler.get (rh,
connection,
args);
}
if (NULL != root)
json_decref (root);
return ret;
}
/**
* Handle a "/seed" request.
*
* @param rh context of the handler
* @param connection the MHD connection to handle
* @param args array of additional options (must be empty for this function)
* @return MHD result code
*/
static MHD_RESULT
handler_seed (const struct TEH_RequestHandler *rh,
struct MHD_Connection *connection,
const char *const args[])
{
#define SEED_SIZE 32
char *body;
MHD_RESULT ret;
struct MHD_Response *resp;
(void) rh;
body = malloc (SEED_SIZE); /* must use malloc(), because MHD will use free() */
if (NULL == body)
return MHD_NO;
GNUNET_CRYPTO_random_block (GNUNET_CRYPTO_QUALITY_NONCE,
body,
SEED_SIZE);
resp = MHD_create_response_from_buffer (SEED_SIZE,
body,
MHD_RESPMEM_MUST_FREE);
TALER_MHD_add_global_headers (resp);
ret = MHD_queue_response (connection,
MHD_HTTP_OK,
resp);
GNUNET_break (MHD_YES == ret);
MHD_destroy_response (resp);
return ret;
#undef SEED_SIZE
}
/**
* Handle incoming HTTP request.
*
* @param cls closure for MHD daemon (unused)
* @param connection the connection
* @param url the requested url
* @param method the method (POST, GET, ...)
* @param version HTTP version (ignored)
* @param upload_data request data
* @param upload_data_size size of @a upload_data in bytes
* @param con_cls closure for request (a `struct Buffer *`)
* @return MHD result code
*/
static MHD_RESULT
handle_mhd_request (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 **con_cls)
{
static struct TEH_RequestHandler handlers[] = {
/* /robots.txt: disallow everything */
{
.url = "robots.txt",
.method = MHD_HTTP_METHOD_GET,
.handler.get = &TEH_handler_static_response,
.mime_type = "text/plain",
.data = "User-agent: *\nDisallow: /\n",
.response_code = MHD_HTTP_OK
},
/* Landing page, tell humans to go away. */
{
.url = "",
.method = MHD_HTTP_METHOD_GET,
.handler.get = TEH_handler_static_response,
.mime_type = "text/plain",
.data =
"Hello, I'm the Taler exchange. This HTTP server is not for humans.\n",
.response_code = MHD_HTTP_OK
},
/* AGPL licensing page, redirect to source. As per the AGPL-license, every
deployment is required to offer the user a download of the source of
the actual deployment. We make this easy by including a redirect to the
source here. */
{
.url = "agpl",
.method = MHD_HTTP_METHOD_GET,
.handler.get = &TEH_handler_agpl_redirect
},
{
.url = "seed",
.method = MHD_HTTP_METHOD_GET,
.handler.get = &handler_seed
},
/* Terms of service */
{
.url = "terms",
.method = MHD_HTTP_METHOD_GET,
.handler.get = &TEH_handler_terms
},
/* Privacy policy */
{
.url = "privacy",
.method = MHD_HTTP_METHOD_GET,
.handler.get = &TEH_handler_privacy
},
/* Return key material and fundamental properties for this exchange */
{
.url = "keys",
.method = MHD_HTTP_METHOD_GET,
.handler.get = &TEH_handler_keys,
},
/* Requests for wiring information */
{
.url = "wire",
.method = MHD_HTTP_METHOD_GET,
.handler.get = &TEH_handler_wire
},
/* Withdrawing coins / interaction with reserves */
{
.url = "reserves",
.method = MHD_HTTP_METHOD_GET,
.handler.get = &TEH_handler_reserves_get,
.nargs = 1
},
{
.url = "reserves",
.method = MHD_HTTP_METHOD_POST,
.handler.post = &TEH_handler_withdraw,
.nargs = 2
},
/* coins */
{
.url = "coins",
.method = MHD_HTTP_METHOD_POST,
.handler.post = &handle_post_coins,
.nargs = 2
},
{
.url = "coins",
.method = MHD_HTTP_METHOD_GET,
.handler.get = TEH_handler_link,
.nargs = 2,
},
/* refreshes/$RCH/reveal */
{
.url = "refreshes",
.method = MHD_HTTP_METHOD_POST,
.handler.post = &TEH_handler_reveal,
.nargs = 2
},
/* tracking transfers */
{
.url = "transfers",
.method = MHD_HTTP_METHOD_GET,
.handler.get = &TEH_handler_transfers_get,
.nargs = 1
},
/* tracking deposits */
{
.url = "deposits",
.method = MHD_HTTP_METHOD_GET,
.handler.get = &TEH_handler_deposits_get,
.nargs = 4
},
/* mark end of list */
{
.url = NULL
}
};
struct ExchangeHttpRequestClosure *ecls = *con_cls;
void **inner_cls;
struct GNUNET_AsyncScopeSave old_scope;
const char *correlation_id = NULL;
(void) cls;
(void) version;
if (NULL == ecls)
{
unsigned long long cnt;
GNUNET_log (GNUNET_ERROR_TYPE_INFO,
"Handling new request\n");
/* Atomic operation, no need for a lock ;-) */
cnt = __sync_add_and_fetch (&req_count,
1LLU);
if (req_max == cnt)
{
GNUNET_log (GNUNET_ERROR_TYPE_INFO,
"Restarting exchange service after %llu requests\n",
cnt);
(void) kill (getpid (),
SIGHUP);
}
/* We're in a new async scope! */
ecls = *con_cls = GNUNET_new (struct ExchangeHttpRequestClosure);
GNUNET_async_scope_fresh (&ecls->async_scope_id);
/* We only read the correlation ID on the first callback for every client */
correlation_id = MHD_lookup_connection_value (connection,
MHD_HEADER_KIND,
"Taler-Correlation-Id");
if ((NULL != correlation_id) &&
(GNUNET_YES != GNUNET_CURL_is_valid_scope_id (correlation_id)))
{
GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
"illegal incoming correlation ID\n");
correlation_id = NULL;
}
}
inner_cls = &ecls->opaque_post_parsing_context;
GNUNET_async_scope_enter (&ecls->async_scope_id,
&old_scope);
if (NULL != correlation_id)
GNUNET_log (GNUNET_ERROR_TYPE_INFO,
"Handling request (%s) for URL '%s', correlation_id=%s\n",
method,
url,
correlation_id);
else
GNUNET_log (GNUNET_ERROR_TYPE_INFO,
"Handling request (%s) for URL '%s'\n",
method,
url);
/* on repeated requests, check our cache first */
if (NULL != ecls->rh)
{
MHD_RESULT ret;
const char *start;
if ('\0' == url[0])
/* strange, should start with '/', treat as just "/" */
url = "/";
start = strchr (url + 1, '/');
if (NULL == start)
start = "";
ret = proceed_with_handler (ecls->rh,
connection,
start,
inner_cls,
upload_data,
upload_data_size);
GNUNET_async_scope_restore (&old_scope);
return ret;
}
if (0 == strcasecmp (method,
MHD_HTTP_METHOD_HEAD))
method = MHD_HTTP_METHOD_GET; /* treat HEAD as GET here, MHD will do the rest */
/* parse first part of URL */
{
int found = GNUNET_NO;
size_t tok_size;
const char *tok;
const char *rest;
if ('\0' == url[0])
/* strange, should start with '/', treat as just "/" */
url = "/";
tok = url + 1;
rest = strchr (tok, '/');
if (NULL == rest)
{
tok_size = strlen (tok);
}
else
{
tok_size = rest - tok;
rest++; /* skip over '/' */
}
for (unsigned int i = 0; NULL != handlers[i].url; i++)
{
struct TEH_RequestHandler *rh = &handlers[i];
if ( (0 != strncmp (tok,
rh->url,
tok_size)) ||
(tok_size != strlen (rh->url) ) )
continue;
found = GNUNET_YES;
/* The URL is a match! What we now do depends on the method. */
if (0 == strcasecmp (method, MHD_HTTP_METHOD_OPTIONS))
{
GNUNET_async_scope_restore (&old_scope);
return TALER_MHD_reply_cors_preflight (connection);
}
GNUNET_assert (NULL != rh->method);
if (0 == strcasecmp (method,
rh->method))
{
MHD_RESULT ret;
/* cache to avoid the loop next time */
ecls->rh = rh;
/* run handler */
ret = proceed_with_handler (rh,
connection,
url + tok_size + 1,
inner_cls,
upload_data,
upload_data_size);
GNUNET_async_scope_restore (&old_scope);
return ret;
}
}
if (GNUNET_YES == found)
{
/* we found a matching address, but the method is wrong */
GNUNET_break_op (0);
return TALER_MHD_reply_with_error (connection,
MHD_HTTP_METHOD_NOT_ALLOWED,
TALER_EC_METHOD_INVALID,
"The HTTP method used is invalid for this URL");
}
}
/* No handler matches, generate not found */
{
MHD_RESULT ret;
ret = TALER_MHD_reply_with_error (connection,
MHD_HTTP_NOT_FOUND,
TALER_EC_ENDPOINT_UNKNOWN,
"No handler found for the given URL");
GNUNET_async_scope_restore (&old_scope);
return ret;
}
}
/**
* Load configuration parameters for the exchange
* server into the corresponding global variables.
*
* @return #GNUNET_OK on success
*/
static enum GNUNET_GenericReturnValue
exchange_serve_process_config (void)
{
if (GNUNET_OK !=
GNUNET_CONFIGURATION_get_value_number (TEH_cfg,
"exchange",
"MAX_REQUESTS",
&req_max))
{
req_max = ULONG_LONG_MAX;
}
if (GNUNET_OK !=
GNUNET_CONFIGURATION_get_value_time (TEH_cfg,
"exchange",
"MAX_KEYS_CACHING",
&TEH_max_keys_caching))
{
GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
"exchange",
"MAX_KEYS_CACHING",
"valid relative time expected");
return GNUNET_SYSERR;
}
if (GNUNET_OK !=
GNUNET_CONFIGURATION_get_value_filename (TEH_cfg,
"exchange",
"KEYDIR",
&TEH_exchange_directory))
{
GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR,
"exchange",
"KEYDIR");
return GNUNET_SYSERR;
}
if (GNUNET_OK !=
GNUNET_CONFIGURATION_get_value_filename (TEH_cfg,
"exchange",
"REVOCATION_DIR",
&TEH_revocation_directory))
{
GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR,
"exchange",
"REVOCATION_DIR");
return GNUNET_SYSERR;
}
{
char *master_public_key_str;
if (GNUNET_OK !=
GNUNET_CONFIGURATION_get_value_string (TEH_cfg,
"exchange",
"MASTER_PUBLIC_KEY",
&master_public_key_str))
{
GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR,
"exchange",
"master_public_key");
return GNUNET_SYSERR;
}
if (GNUNET_OK !=
GNUNET_CRYPTO_eddsa_public_key_from_string (master_public_key_str,
strlen (
master_public_key_str),
&TEH_master_public_key.
eddsa_pub))
{
GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
"Invalid master public key given in exchange configuration.");
GNUNET_free (master_public_key_str);
return GNUNET_SYSERR;
}
GNUNET_free (master_public_key_str);
}
GNUNET_log (GNUNET_ERROR_TYPE_INFO,
"Launching exchange with public key `%s'...\n",
GNUNET_p2s (&TEH_master_public_key.eddsa_pub));
if (GNUNET_OK !=
TEH_WIRE_init (TEH_cfg))
{
GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
"Failed to setup wire subsystem\n");
return GNUNET_SYSERR;
}
if (NULL ==
(TEH_plugin = TALER_EXCHANGEDB_plugin_load (TEH_cfg)))
{
GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
"Failed to initialize DB subsystem\n");
TEH_WIRE_done ();
return GNUNET_SYSERR;
}
if (GNUNET_OK !=
TALER_MHD_parse_config (TEH_cfg,
"exchange",
&serve_port,
&serve_unixpath,
&unixpath_mode))
{
GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
"Failed to setup HTTPd subsystem\n");
TEH_WIRE_done ();
return GNUNET_SYSERR;
}
return GNUNET_OK;
}
/**
* Called when the main thread exits, writes out performance
* stats if requested.
*/
static void
write_stats (void)
{
struct GNUNET_DISK_FileHandle *fh;
pid_t pid = getpid ();
char *benchmark_dir;
char *s;
struct rusage usage;
benchmark_dir = getenv ("GNUNET_BENCHMARK_DIR");
if (NULL == benchmark_dir)
return;
GNUNET_asprintf (&s,
"%s/taler-exchange-%llu-%llu.txt",
benchmark_dir,
(unsigned long long) pid);
fh = GNUNET_DISK_file_open (s,
(GNUNET_DISK_OPEN_WRITE
| GNUNET_DISK_OPEN_TRUNCATE
| GNUNET_DISK_OPEN_CREATE),
(GNUNET_DISK_PERM_USER_READ
| GNUNET_DISK_PERM_USER_WRITE));
GNUNET_free (s);
if (NULL == fh)
return; /* permission denied? */
/* Collect stats, summed up for all threads */
GNUNET_assert (0 ==
getrusage (RUSAGE_SELF,
&usage));
GNUNET_asprintf (&s,
"time_exchange sys %llu user %llu\n",
(unsigned long long) (usage.ru_stime.tv_sec * 1000 * 1000
+ usage.ru_stime.tv_usec),
(unsigned long long) (usage.ru_utime.tv_sec * 1000 * 1000
+ usage.ru_utime.tv_usec));
GNUNET_assert (GNUNET_SYSERR !=
GNUNET_DISK_file_write_blocking (fh,
s,
strlen (s)));
GNUNET_free (s);
GNUNET_assert (GNUNET_OK ==
GNUNET_DISK_file_close (fh));
}
/* Developer logic for supporting the `-f' option. */
#if HAVE_DEVELOPER
/**
* Option `-f' (specifies an input file to give to the HTTP server).
*/
static char *input_filename;
/**
* We finished handling the request and should now terminate.
*/
static int do_terminate;
/**
* Run 'nc' or 'ncat' as a fake HTTP client using #input_filename
* as the input for the request. If launching the client worked,
* run the #TEH_KS_loop() event loop as usual.
*
* @return child pid
*/
static pid_t
run_fake_client (void)
{
pid_t cld;
char ports[6];
int fd;
if (0 == strcmp (input_filename,
"-"))
fd = STDIN_FILENO;
else
fd = open (input_filename, O_RDONLY);
if (-1 == fd)
{
fprintf (stderr,
"Failed to open `%s': %s\n",
input_filename,
strerror (errno));
return -1;
}
/* Fake HTTP client request with #input_filename as input.
We do this using the nc tool. */
GNUNET_snprintf (ports,
sizeof (ports),
"%u",
serve_port);
if (0 == (cld = fork ()))
{
GNUNET_break (0 == close (0));
GNUNET_break (0 == dup2 (fd, 0));
GNUNET_break (0 == close (fd));
if ( (0 != execlp ("nc",
"nc",
"localhost",
ports,
"-w", "30",
NULL)) &&
(0 != execlp ("ncat",
"ncat",
"localhost",
ports,
"-i", "30",
NULL)) )
{
fprintf (stderr,
"Failed to run both `nc' and `ncat': %s\n",
strerror (errno));
}
_exit (1);
}
/* parent process */
if (0 != strcmp (input_filename,
"-"))
GNUNET_break (0 == close (fd));
return cld;
}
/**
* Signature of the callback used by MHD to notify the application
* about completed connections. If we are running in test-mode with
* an #input_filename, this function is used to terminate the HTTPD
* after the first request has been processed.
*
* @param cls client-defined closure, NULL
* @param connection connection handle (ignored)
* @param socket_context socket-specific pointer (ignored)
* @param toe reason for connection notification
*/
static void
connection_done (void *cls,
struct MHD_Connection *connection,
void **socket_context,
enum MHD_ConnectionNotificationCode toe)
{
(void) cls;
(void) connection;
(void) socket_context;
/* We only act if the connection is closed. */
if (MHD_CONNECTION_NOTIFY_CLOSED != toe)
return;
GNUNET_log (GNUNET_ERROR_TYPE_INFO,
"Connection done!\n");
do_terminate = GNUNET_YES;
}
/**
* Run the exchange to serve a single request only, without threads.
*
* @return #GNUNET_OK on success
*/
static int
run_single_request (void)
{
pid_t cld;
int status;
/* run only the testfile input, then terminate */
mhd
= MHD_start_daemon (MHD_USE_PIPE_FOR_SHUTDOWN
| MHD_USE_DEBUG | MHD_USE_DUAL_STACK
| MHD_USE_TCP_FASTOPEN,
0, /* pick free port */
NULL, NULL,
&handle_mhd_request, NULL,
MHD_OPTION_LISTEN_BACKLOG_SIZE, (unsigned int) 10,
MHD_OPTION_EXTERNAL_LOGGER, &TALER_MHD_handle_logs,
NULL,
MHD_OPTION_NOTIFY_COMPLETED,
&handle_mhd_completion_callback, NULL,
MHD_OPTION_CONNECTION_TIMEOUT, connection_timeout,
MHD_OPTION_NOTIFY_CONNECTION, &connection_done, NULL,
MHD_OPTION_END);
if (NULL == mhd)
{
fprintf (stderr,
"Failed to start HTTP server.\n");
return GNUNET_SYSERR;
}
serve_port = MHD_get_daemon_info (mhd,
MHD_DAEMON_INFO_BIND_PORT)->port;
cld = run_fake_client ();
if (-1 == cld)
return GNUNET_SYSERR;
/* run the event loop until #connection_done() was called */
while (GNUNET_NO == do_terminate)
{
fd_set rs;
fd_set ws;
fd_set es;
struct timeval tv;
MHD_UNSIGNED_LONG_LONG timeout;
int maxsock = -1;
int have_tv;
FD_ZERO (&rs);
FD_ZERO (&ws);
FD_ZERO (&es);
if (MHD_YES !=
MHD_get_fdset (mhd,
&rs,
&ws,
&es,
&maxsock))
{
GNUNET_break (0);
return GNUNET_SYSERR;
}
have_tv = MHD_get_timeout (mhd,
&timeout);
tv.tv_sec = timeout / 1000;
tv.tv_usec = 1000 * (timeout % 1000);
if (-1 == select (maxsock + 1,
&rs,
&ws,
&es,
have_tv ? &tv : NULL))
{
GNUNET_break (0);
return GNUNET_SYSERR;
}
MHD_run (mhd);
}
MHD_stop_daemon (mhd);
mhd = NULL;
if (cld != waitpid (cld,
&status,
0))
fprintf (stderr,
"Waiting for `nc' child failed: %s\n",
strerror (errno));
return GNUNET_OK;
}
/* end of HAVE_DEVELOPER */
#endif
/**
* Run the ordinary multi-threaded main loop and the logic to
* wait for CTRL-C.
*
* @param fh listen socket
* @param argv command line arguments
* @return #GNUNET_OK on success
*/
static int
run_main_loop (int fh,
char *const *argv)
{
int ret;
mhd
= MHD_start_daemon (MHD_USE_SELECT_INTERNALLY | MHD_USE_PIPE_FOR_SHUTDOWN
| MHD_USE_DEBUG | MHD_USE_DUAL_STACK
| MHD_USE_INTERNAL_POLLING_THREAD
| MHD_USE_TCP_FASTOPEN,
(-1 == fh) ? serve_port : 0,
NULL, NULL,
&handle_mhd_request, NULL,
MHD_OPTION_THREAD_POOL_SIZE, (unsigned int) 32,
MHD_OPTION_LISTEN_BACKLOG_SIZE, (unsigned int) 1024,
MHD_OPTION_LISTEN_SOCKET, fh,
MHD_OPTION_EXTERNAL_LOGGER, &TALER_MHD_handle_logs,
NULL,
MHD_OPTION_NOTIFY_COMPLETED,
&handle_mhd_completion_callback, NULL,
MHD_OPTION_CONNECTION_TIMEOUT, connection_timeout,
MHD_OPTION_END);
if (NULL == mhd)
{
fprintf (stderr,
"Failed to start HTTP server.\n");
return GNUNET_SYSERR;
}
atexit (&write_stats);
ret = TEH_KS_loop ();
switch (ret)
{
case GNUNET_OK:
case GNUNET_SYSERR:
MHD_stop_daemon (mhd);
break;
case GNUNET_NO:
{
MHD_socket sock = MHD_quiesce_daemon (mhd);
pid_t chld;
int flags;
/* Set flags to make 'sock' inherited by child */
flags = fcntl (sock, F_GETFD);
GNUNET_assert (-1 != flags);
flags &= ~FD_CLOEXEC;
GNUNET_assert (-1 != fcntl (sock, F_SETFD, flags));
chld = fork ();
if (-1 == chld)
{
/* fork() failed, continue clean up, unhappily */
GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR,
"fork");
}
if (0 == chld)
{
char pids[12];
/* exec another taler-exchange-httpd, passing on the listen socket;
as in systemd it is expected to be on FD #3 */
if (3 != dup2 (sock, 3))
{
GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR,
"dup2");
_exit (1);
}
/* Tell the child that it is the desired recipient for FD #3 */
GNUNET_snprintf (pids,
sizeof (pids),
"%u",
getpid ());
setenv ("LISTEN_PID", pids, 1);
setenv ("LISTEN_FDS", "1", 1);
/* Finally, exec the (presumably) more recent exchange binary */
execvp ("taler-exchange-httpd",
argv);
GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR,
"execvp");
_exit (1);
}
/* we're the original process, handle remaining contextions
before exiting; as the listen socket is no longer used,
close it here */
GNUNET_break (0 == close (sock));
while (0 != MHD_get_daemon_info (mhd,
MHD_DAEMON_INFO_CURRENT_CONNECTIONS)->
num_connections)
sleep (1);
/* Now we're really done, practice clean shutdown */
MHD_stop_daemon (mhd);
}
break;
default:
GNUNET_break (0);
MHD_stop_daemon (mhd);
break;
}
return ret;
}
/**
* The main function of the taler-exchange-httpd server ("the exchange").
*
* @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)
{
char *cfgfile = NULL;
char *loglev = NULL;
char *logfile = NULL;
int connection_close = GNUNET_NO;
const struct GNUNET_GETOPT_CommandLineOption options[] = {
GNUNET_GETOPT_option_flag ('a',
"allow-timetravel",
"allow clients to request /keys for arbitrary timestamps (for testing and development only)",
&TEH_allow_keys_timetravel),
GNUNET_GETOPT_option_flag ('C',
"connection-close",
"force HTTP connections to be closed after each request",
&connection_close),
GNUNET_GETOPT_option_cfgfile (&cfgfile),
GNUNET_GETOPT_option_uint ('t',
"timeout",
"SECONDS",
"after how long do connections timeout by default (in seconds)",
&connection_timeout),
GNUNET_GETOPT_option_timetravel ('T',
"timetravel"),
#if HAVE_DEVELOPER
GNUNET_GETOPT_option_filename ('f',
"file-input",
"FILENAME",
"run in test-mode using FILENAME as the HTTP request to process, use '-' to read from stdin",
&input_filename),
#endif
GNUNET_GETOPT_option_help (
"HTTP server providing a RESTful API to access a Taler exchange"),
GNUNET_GETOPT_option_loglevel (&loglev),
GNUNET_GETOPT_option_logfile (&logfile),
GNUNET_GETOPT_option_version (VERSION "-" VCS_VERSION),
GNUNET_GETOPT_OPTION_END
};
int ret;
const char *listen_pid;
const char *listen_fds;
int fh = -1;
enum TALER_MHD_GlobalOptions go;
if (0 >=
GNUNET_GETOPT_run ("taler-exchange-httpd",
options,
argc, argv))
return 1;
go = TALER_MHD_GO_NONE;
if (connection_close)
go |= TALER_MHD_GO_FORCE_CONNECTION_CLOSE;
TALER_MHD_setup (go);
GNUNET_assert (GNUNET_OK ==
GNUNET_log_setup ("taler-exchange-httpd",
(NULL == loglev) ? "INFO" : loglev,
logfile));
GNUNET_free_non_null (loglev);
GNUNET_free_non_null (logfile);
if (NULL == cfgfile)
cfgfile = GNUNET_strdup (GNUNET_OS_project_data_get ()->user_config_file);
TEH_cfg = GNUNET_CONFIGURATION_create ();
if (GNUNET_SYSERR ==
GNUNET_CONFIGURATION_load (TEH_cfg,
cfgfile))
{
GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
"Malformed configuration file `%s', exit ...\n",
cfgfile);
GNUNET_free_non_null (cfgfile);
return 1;
}
GNUNET_free_non_null (cfgfile);
if (GNUNET_OK !=
exchange_serve_process_config ())
return 1;
TEH_load_terms (TEH_cfg);
/* check for systemd-style FD passing */
listen_pid = getenv ("LISTEN_PID");
listen_fds = getenv ("LISTEN_FDS");
if ( (NULL != listen_pid) &&
(NULL != listen_fds) &&
(getpid () == strtol (listen_pid,
NULL,
10)) &&
(1 == strtoul (listen_fds,
NULL,
10)) )
{
int flags;
fh = 3;
flags = fcntl (fh,
F_GETFD);
if ( (-1 == flags) &&
(EBADF == errno) )
{
fprintf (stderr,
"Bad listen socket passed, ignored\n");
fh = -1;
}
flags |= FD_CLOEXEC;
if ( (-1 != fh) &&
(0 != fcntl (fh,
F_SETFD,
flags)) )
GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR,
"fcntl");
}
/* initialize #internal_key_state with an RC of 1 */
ret = TEH_KS_init ();
if (GNUNET_OK == ret)
{
#if HAVE_DEVELOPER
if (NULL != input_filename)
{
ret = run_single_request ();
}
else
#endif
{
/* consider unix path */
if ( (-1 == fh) &&
(NULL != serve_unixpath) )
{
fh = TALER_MHD_open_unix_path (serve_unixpath,
unixpath_mode);
if (-1 == fh)
return 1;
}
ret = run_main_loop (fh,
argv);
}
/* release #internal_key_state */
TEH_KS_free ();
}
TALER_EXCHANGEDB_plugin_unload (TEH_plugin);
TEH_WIRE_done ();
return (GNUNET_SYSERR == ret) ? 1 : 0;
}
/* end of taler-exchange-httpd.c */
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