/*
This file is part of TALER
Copyright (C) 2014, 2015, 2016, 2018 Inria and GNUnet e.V.
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
*/
/**
* @file taler-auditor-httpd.c
* @brief Serve the HTTP interface of the auditor
* @author Florian Dold
* @author Benedikt Mueller
* @author Christian Grothoff
*/
#include "platform.h"
#include
#include
#include
#include
#include
#include "taler_auditordb_lib.h"
#include "taler-auditor-httpd_deposit-confirmation.h"
#include "taler-auditor-httpd_exchanges.h"
#include "taler-auditor-httpd_parsing.h"
#include "taler-auditor-httpd_mhd.h"
#include "taler-auditor-httpd.h"
/**
* Backlog for listen operation on unix domain sockets.
*/
#define UNIX_BACKLOG 500
/**
* Should we return "Connection: close" in each response?
*/
int TAH_auditor_connection_close;
/**
* The auditor's configuration (global)
*/
struct GNUNET_CONFIGURATION_Handle *cfg;
/**
* Our DB plugin.
*/
struct TALER_AUDITORDB_Plugin *TAH_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;
/**
* Pipe used for signaling reloading of our key state.
*/
static int reload_pipe[2];
/**
* Handle a signal, writing relevant signal numbers to the pipe.
*
* @param signal_number the signal number
*/
static void
handle_signal (int signal_number)
{
ssize_t res;
char c = signal_number;
res = write (reload_pipe[1],
&c,
1);
if ( (res < 0) &&
(EINTR != errno) )
{
GNUNET_break (0);
return;
}
if (0 == res)
{
GNUNET_break (0);
return;
}
}
/**
* Call #handle_signal() to pass the received signal via
* the control pipe.
*/
static void
handle_sigint ()
{
handle_signal (SIGINT);
}
/**
* Call #handle_signal() to pass the received signal via
* the control pipe.
*/
static void
handle_sigterm ()
{
handle_signal (SIGTERM);
}
/**
* Call #handle_signal() to pass the received signal via
* the control pipe.
*/
static void
handle_sighup ()
{
handle_signal (SIGHUP);
}
/**
* Call #handle_signal() to pass the received signal via
* the control pipe.
*/
static void
handle_sigchld ()
{
handle_signal (SIGCHLD);
}
/**
* Read signals from a pipe in a loop, and reload keys from disk if
* SIGUSR1 is received, terminate if SIGTERM/SIGINT is received, and
* restart if SIGHUP is received.
*
* @return #GNUNET_SYSERR on errors,
* #GNUNET_OK to terminate normally
* #GNUNET_NO to restart an update version of the binary
*/
static int
signal_loop (void)
{
struct GNUNET_SIGNAL_Context *sigterm;
struct GNUNET_SIGNAL_Context *sigint;
struct GNUNET_SIGNAL_Context *sighup;
struct GNUNET_SIGNAL_Context *sigchld;
int ret;
char c;
ssize_t res;
if (0 != pipe (reload_pipe))
{
GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR,
"pipe");
return GNUNET_SYSERR;
}
sigterm = GNUNET_SIGNAL_handler_install (SIGTERM,
&handle_sigterm);
sigint = GNUNET_SIGNAL_handler_install (SIGINT,
&handle_sigint);
sighup = GNUNET_SIGNAL_handler_install (SIGHUP,
&handle_sighup);
sigchld = GNUNET_SIGNAL_handler_install (SIGCHLD,
&handle_sigchld);
ret = 2;
while (2 == ret)
{
errno = 0;
res = read (reload_pipe[0],
&c,
1);
if ((res < 0) && (EINTR != errno))
{
GNUNET_break (0);
ret = GNUNET_SYSERR;
break;
}
if (EINTR == errno)
{
ret = 2;
continue;
}
switch (c)
{
case SIGTERM:
case SIGINT:
/* terminate */
ret = GNUNET_OK;
break;
case SIGHUP:
/* restart updated binary */
ret = GNUNET_NO;
break;
#if HAVE_DEVELOPER
case SIGCHLD:
/* running in test-mode, test finished, terminate */
ret = GNUNET_OK;
break;
#endif
default:
/* unexpected character */
GNUNET_break (0);
break;
}
}
GNUNET_SIGNAL_handler_uninstall (sigterm);
GNUNET_SIGNAL_handler_uninstall (sigint);
GNUNET_SIGNAL_handler_uninstall (sighup);
GNUNET_SIGNAL_handler_uninstall (sigchld);
GNUNET_break (0 == close (reload_pipe[0]));
GNUNET_break (0 == close (reload_pipe[1]));
return ret;
}
/**
* 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)
{
if (NULL == *con_cls)
return;
TAH_PARSE_post_cleanup_callback (*con_cls);
*con_cls = NULL;
}
/**
* 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 int
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 TAH_RequestHandler handlers[] =
{
/* Our most popular handler (thus first!), used by merchants to
probabilistically report us their deposit confirmations. */
{ "/deposit-confirmation", MHD_HTTP_METHOD_PUT, "text/plain",
NULL, 0,
&TAH_DEPOSIT_CONFIRMATION_handler, MHD_HTTP_OK },
{ "/exchanges", MHD_HTTP_METHOD_GET, "text/plain",
NULL, 0,
&TAH_EXCHANGES_handler, MHD_HTTP_OK },
/* Landing page, for now tells humans to go away (FIXME: replace
with auditor's welcome page!) */
{ "/", MHD_HTTP_METHOD_GET, "text/plain",
"Hello, I'm the Taler auditor. This HTTP server is not for humans.\n", 0,
&TAH_MHD_handler_static_response, MHD_HTTP_OK },
/* /robots.txt: disallow everything */
{ "/robots.txt", MHD_HTTP_METHOD_GET, "text/plain",
"User-agent: *\nDisallow: /\n", 0,
&TAH_MHD_handler_static_response, 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. We make this easy by including a redirect to the source
here. */
{ "/agpl", MHD_HTTP_METHOD_GET, "text/plain",
NULL, 0,
&TAH_MHD_handler_agpl_redirect, MHD_HTTP_FOUND },
{ NULL, NULL, NULL, NULL, 0, 0 }
};
static struct TAH_RequestHandler h404 =
{
"", NULL, "text/html",
"404: not found", 0,
&TAH_MHD_handler_static_response, MHD_HTTP_NOT_FOUND
};
struct TAH_RequestHandler *rh;
GNUNET_log (GNUNET_ERROR_TYPE_INFO,
"Handling request for URL '%s'\n",
url);
if (0 == strcasecmp (method,
MHD_HTTP_METHOD_HEAD))
method = MHD_HTTP_METHOD_GET; /* treat HEAD as GET here, MHD will do the rest */
for (unsigned int i=0;NULL != handlers[i].url;i++)
{
rh = &handlers[i];
if ( (0 == strcasecmp (url,
rh->url)) &&
( (NULL == rh->method) ||
(0 == strcasecmp (method,
rh->method)) ) )
return rh->handler (rh,
connection,
con_cls,
upload_data,
upload_data_size);
}
return TAH_MHD_handler_static_response (&h404,
connection,
con_cls,
upload_data,
upload_data_size);
}
/**
* Parse the configuration to determine on which port
* or UNIX domain path we should run an HTTP service.
*
* @param section section of the configuration to parse ("auditor" or "auditor-admin")
* @param[out] rport set to the port number, or 0 for none
* @param[out] unix_path set to the UNIX path, or NULL for none
* @param[out] unix_mode set to the mode to be used for @a unix_path
* @return #GNUNET_OK on success
*/
static int
parse_port_config (const char *section,
uint16_t *rport,
char **unix_path,
mode_t *unix_mode)
{
const char *choices[] = {"tcp", "unix"};
const char *serve_type;
unsigned long long port;
if (GNUNET_OK !=
GNUNET_CONFIGURATION_get_value_choice (cfg,
section,
"serve",
choices,
&serve_type))
{
GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
section,
"serve",
"serve type required");
return GNUNET_SYSERR;
}
if (0 == strcmp (serve_type, "tcp"))
{
if (GNUNET_OK !=
GNUNET_CONFIGURATION_get_value_number (cfg,
section,
"port",
&port))
{
GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
section,
"port",
"port number required");
return GNUNET_SYSERR;
}
if ( (0 == port) ||
(port > UINT16_MAX) )
{
fprintf (stderr,
"Invalid configuration (value out of range): %llu is not a valid port\n",
port);
return GNUNET_SYSERR;
}
*rport = (uint16_t) port;
*unix_path = NULL;
return GNUNET_OK;
}
if (0 == strcmp (serve_type, "unix"))
{
struct sockaddr_un s_un;
char *modestring;
if (GNUNET_OK !=
GNUNET_CONFIGURATION_get_value_filename (cfg,
section,
"unixpath",
unix_path))
{
GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
section,
"unixpath",
"unixpath required");
return GNUNET_SYSERR;
}
if (strlen (*unix_path) >= sizeof (s_un.sun_path))
{
fprintf (stderr,
"Invalid configuration: unix path too long\n");
return GNUNET_SYSERR;
}
if (GNUNET_OK !=
GNUNET_CONFIGURATION_get_value_string (cfg,
section,
"UNIXPATH_MODE",
&modestring))
{
GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR,
section,
"UNIXPATH_MODE");
return GNUNET_SYSERR;
}
errno = 0;
*unix_mode = (mode_t) strtoul (modestring, NULL, 8);
if (0 != errno)
{
GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
section,
"UNIXPATH_MODE",
"must be octal number");
GNUNET_free (modestring);
return GNUNET_SYSERR;
}
GNUNET_free (modestring);
return GNUNET_OK;
}
/* not reached */
GNUNET_assert (0);
return GNUNET_SYSERR;
}
/**
* Load configuration parameters for the auditor
* server into the corresponding global variables.
*
* @return #GNUNET_OK on success
*/
static int
auditor_serve_process_config ()
{
if (NULL ==
(TAH_plugin = TALER_AUDITORDB_plugin_load (cfg)))
{
fprintf (stderr,
"Failed to initialize DB subsystem\n");
return GNUNET_SYSERR;
}
if (GNUNET_OK !=
parse_port_config ("auditor",
&serve_port,
&serve_unixpath,
&unixpath_mode))
{
return GNUNET_SYSERR;
}
return GNUNET_OK;
}
/**
* Function called for logging by MHD.
*
* @param cls closure, NULL
* @param fm format string (`printf()`-style)
* @param ap arguments to @a fm
*/
static void
handle_mhd_logs (void *cls,
const char *fm,
va_list ap)
{
static int cache;
char buf[2048];
if (-1 == cache)
return;
if (0 == cache)
{
if (0 ==
GNUNET_get_log_call_status (GNUNET_ERROR_TYPE_INFO,
"auditor-httpd",
__FILE__,
__FUNCTION__,
__LINE__))
{
cache = -1;
return;
}
}
cache = 1;
vsnprintf (buf,
sizeof (buf),
fm,
ap);
GNUNET_log_from_nocheck (GNUNET_ERROR_TYPE_INFO,
"auditor-httpd",
"%s",
buf);
}
/**
* Open UNIX domain socket for listining at @a unix_path with
* permissions @a unix_mode.
*
* @param unix_path where to listen
* @param unix_mode access permissions to set
* @return -1 on error, otherwise the listen socket
*/
static int
open_unix_path (const char *unix_path,
mode_t unix_mode)
{
struct GNUNET_NETWORK_Handle *nh;
struct sockaddr_un *un;
int fd;
if (sizeof (un->sun_path) <= strlen (unix_path))
{
fprintf (stderr,
"unixpath `%s' too long\n",
unix_path);
return -1;
}
GNUNET_log (GNUNET_ERROR_TYPE_INFO,
"Creating listen socket '%s' with mode %o\n",
unix_path,
unix_mode);
if (GNUNET_OK !=
GNUNET_DISK_directory_create_for_file (unix_path))
{
GNUNET_log_strerror_file (GNUNET_ERROR_TYPE_ERROR,
"mkdir",
unix_path);
}
un = GNUNET_new (struct sockaddr_un);
un->sun_family = AF_UNIX;
strncpy (un->sun_path,
unix_path,
sizeof (un->sun_path) - 1);
GNUNET_NETWORK_unix_precheck (un);
if (NULL == (nh = GNUNET_NETWORK_socket_create (AF_UNIX,
SOCK_STREAM,
0)))
{
fprintf (stderr,
"create failed for AF_UNIX\n");
GNUNET_free (un);
return -1;
}
if (GNUNET_OK !=
GNUNET_NETWORK_socket_bind (nh,
(void *) un,
sizeof (struct sockaddr_un)))
{
fprintf (stderr,
"bind failed for AF_UNIX\n");
GNUNET_free (un);
GNUNET_NETWORK_socket_close (nh);
return -1;
}
GNUNET_free (un);
if (GNUNET_OK !=
GNUNET_NETWORK_socket_listen (nh,
UNIX_BACKLOG))
{
fprintf (stderr,
"listen failed for AF_UNIX\n");
GNUNET_NETWORK_socket_close (nh);
return -1;
}
if (0 != chmod (unix_path,
unix_mode))
{
fprintf (stderr,
"chmod failed: %s\n",
strerror (errno));
GNUNET_NETWORK_socket_close (nh);
return -1;
}
GNUNET_log (GNUNET_ERROR_TYPE_INFO,
"set socket '%s' to mode %o\n",
unix_path,
unix_mode);
fd = GNUNET_NETWORK_get_fd (nh);
GNUNET_NETWORK_socket_free_memory_only_ (nh);
return fd;
}
/**
* The main function of the taler-auditor-httpd server ("the auditor").
*
* @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;
const struct GNUNET_GETOPT_CommandLineOption options[] = {
GNUNET_GETOPT_option_flag ('C',
"connection-close",
"force HTTP connections to be closed after each request",
&TAH_auditor_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_help ("HTTP server providing a RESTful API to access a Taler auditor"),
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;
if (0 >=
GNUNET_GETOPT_run ("taler-auditor-httpd",
options,
argc, argv))
return 1;
GNUNET_assert (GNUNET_OK ==
GNUNET_log_setup ("taler-auditor-httpd",
(NULL == loglev) ? "INFO" : loglev,
logfile));
if (NULL == cfgfile)
cfgfile = GNUNET_strdup (GNUNET_OS_project_data_get ()->user_config_file);
cfg = GNUNET_CONFIGURATION_create ();
if (GNUNET_SYSERR ==
GNUNET_CONFIGURATION_load (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 !=
auditor_serve_process_config ())
return 1;
/* 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");
}
/* consider unix path */
if ( (-1 == fh) &&
(NULL != serve_unixpath) )
{
fh = open_unix_path (serve_unixpath,
unixpath_mode);
if (-1 == fh)
return 1;
}
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, &handle_mhd_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 1;
}
/* normal behavior */
ret = signal_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-auditor-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 auditor binary */
execvp ("taler-auditor-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;
}
TALER_AUDITORDB_plugin_unload (TAH_plugin);
return (GNUNET_SYSERR == ret) ? 1 : 0;
}
/* end of taler-auditor-httpd.c */