add common setup logic to libtalermhd

src/include/taler_mhd_lib.h

@@ -13,7 +13,6 @@
   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_mhd_lib.h
  * @brief API for generating MHD replies
@@ -154,6 +153,39 @@ int
 TALER_MHD_reply_request_too_large (struct MHD_Connection *connection);
 
 
+/**
+ * Function to call to handle the request by sending
+ * back a redirect to the AGPL source code.
+ *
+ * @param connection the MHD connection to handle
+ * @param url where to redirect for the sources
+ * @return MHD result code
+ */
+int
+TALER_MHD_reply_agpl (struct MHD_Connection *connection,
+                      const char *url);
+
+
+/**
+ * Function to call to handle the request by sending
+ * back static data.
+ *
+ * @param rh context of the handler
+ * @param connection the MHD connection to handle
+ * @param http_status status code to return
+ * @param mime_type content-type to use
+ * @param body response payload
+ * @param body_size number of bytes in @a body
+ * @return MHD result code
+ */
+int
+TALER_MHD_reply_static (struct MHD_Connection *connection,
+                        unsigned int http_status,
+                        const char *mime_type,
+                        const char *body,
+                        size_t *body_size);
+
+
 /**
  * Process a POST request containing a JSON object.  This
  * function realizes an MHD POST processor that will
@@ -261,4 +293,49 @@ TALER_MHD_parse_request_arg_data (struct MHD_Connection *connection,
                                   size_t out_size);
 
 
+/**
+ * Parse the configuration to determine on which port
+ * or UNIX domain path we should run an HTTP service.
+ *
+ * @param cfg configuration to parse
+ * @param section section of the configuration to parse (usually "exchange")
+ * @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
+ */
+int
+TALER_MHD_parse_config (const struct GNUNET_CONFIGURATION_Handle *cfg,
+                        const char *section,
+                        uint16_t *rport,
+                        char **unix_path,
+                        mode_t *unix_mode);
+
+
+/**
+ * Function called for logging by MHD.
+ *
+ * @param cls closure, NULL
+ * @param fm format string (`printf()`-style)
+ * @param ap arguments to @a fm
+ */
+void
+TALER_MHD_handle_logs (void *cls,
+                       const char *fm,
+                       va_list ap);
+
+
+/**
+ * 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
+ */
+int
+TALER_MHD_open_unix_path (const char *unix_path,
+                          mode_t unix_mode);
+
+
 #endif

src/mhd/Makefile.am

@@ -10,6 +10,7 @@ lib_LTLIBRARIES = \
   libtalermhd.la
 
 libtalermhd_la_SOURCES = \
+  mhd_config.c \
   mhd_parsing.c \
   mhd_responses.c 
 libtalermhd_la_LDFLAGS = \

src/mhd/mhd_config.c

@@ -0,0 +1,287 @@
+/*
+  This file is part of TALER
+  Copyright (C) 2014--2019 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 mhd_config.c
+ * @brief functions to configure and setup MHD
+ * @author Florian Dold
+ * @author Benedikt Mueller
+ * @author Christian Grothoff
+ */
+#include "platform.h"
+#include <gnunet/gnunet_util_lib.h>
+#include "taler_mhd_lib.h"
+
+
+/**
+ * Backlog for listen operation on UNIX domain sockets.
+ */
+#define UNIX_BACKLOG 500
+
+
+/**
+ * Parse the configuration to determine on which port
+ * or UNIX domain path we should run an HTTP service.
+ *
+ * @param cfg configuration to parse
+ * @param section section of the configuration to parse (usually "exchange")
+ * @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
+ */
+int
+TALER_MHD_parse_config (const struct GNUNET_CONFIGURATION_Handle *cfg,
+                        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 == strcasecmp (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) )
+    {
+      GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
+                                 section,
+                                 "port",
+                                 "value not in [1,65535]");
+      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))
+    {
+      GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                  "unixpath `%s' is too long\n",
+                  *unix_path);
+      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;
+}
+
+
+/**
+ * Function called for logging by MHD.
+ *
+ * @param cls closure, NULL
+ * @param fm format string (`printf()`-style)
+ * @param ap arguments to @a fm
+ */
+void
+TALER_MHD_handle_logs (void *cls,
+                       const char *fm,
+                       va_list ap)
+{
+  static int cache;
+  char buf[2048];
+
+  (void) cls;
+  if (-1 == cache)
+    return;
+  if (0 == cache)
+  {
+    if (0 ==
+        GNUNET_get_log_call_status (GNUNET_ERROR_TYPE_INFO,
+                                    "libmicrohttpd",
+                                    __FILE__,
+                                    __FUNCTION__,
+                                    __LINE__))
+    {
+      cache = -1;
+      return;
+    }
+  }
+  cache = 1;
+  vsnprintf (buf,
+             sizeof (buf),
+             fm,
+             ap);
+  GNUNET_log_from_nocheck (GNUNET_ERROR_TYPE_INFO,
+                           "libmicrohttpd",
+                           "%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
+ */
+int
+TALER_MHD_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))
+  {
+    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                "unixpath `%s' is too long\n",
+                unix_path);
+    return -1;
+  }
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "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)))
+  {
+    GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR,
+                         "socket");
+    GNUNET_free (un);
+    return -1;
+  }
+  if (GNUNET_OK !=
+      GNUNET_NETWORK_socket_bind (nh,
+                                  (void *) un,
+                                  sizeof (struct sockaddr_un)))
+  {
+    GNUNET_log_strerror_file (GNUNET_ERROR_TYPE_ERROR,
+                              "bind",
+                              unix_path);
+    GNUNET_free (un);
+    GNUNET_NETWORK_socket_close (nh);
+    return -1;
+  }
+  GNUNET_free (un);
+  if (GNUNET_OK !=
+      GNUNET_NETWORK_socket_listen (nh,
+                                    UNIX_BACKLOG))
+  {
+    GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR,
+                         "listen");
+    GNUNET_NETWORK_socket_close (nh);
+    return -1;
+  }
+
+  if (0 != chmod (unix_path,
+                  unix_mode))
+  {
+    GNUNET_log_strerror (GNUNET_ERROR_TYPE_ERROR,
+                         "chmod");
+    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;
+}

src/mhd/mhd_responses.c

@@ -316,4 +316,95 @@ TALER_MHD_reply_request_too_large (struct MHD_Connection *connection)
 }
 
 
+/**
+ * Function to call to handle the request by sending
+ * back a redirect to the AGPL source code.
+ *
+ * @param connection the MHD connection to handle
+ * @param url where to redirect for the sources
+ * @return MHD result code
+ */
+int
+TALER_MHD_reply_agpl (struct MHD_Connection *connection,
+                      const char *url)
+{
+  const char *agpl =
+    "This server is licensed under the Affero GPL. You will now be redirected to the source code.";
+  struct MHD_Response *response;
+  int ret;
+
+  response = MHD_create_response_from_buffer (strlen (agpl),
+                                              (void *) agpl,
+                                              MHD_RESPMEM_PERSISTENT);
+  if (NULL == response)
+  {
+    GNUNET_break (0);
+    return MHD_NO;
+  }
+  TALER_MHD_add_global_headers (response);
+  GNUNET_break (MHD_YES ==
+                MHD_add_response_header (response,
+                                         MHD_HTTP_HEADER_CONTENT_TYPE,
+                                         "text/plain"));
+  if (MHD_NO ==
+      MHD_add_response_header (response,
+                               MHD_HTTP_HEADER_LOCATION,
+                               url))
+  {
+    GNUNET_break (0);
+    MHD_destroy_response (response);
+    return MHD_NO;
+  }
+  ret = MHD_queue_response (connection,
+                            MHD_HTTP_FOUND,
+                            response);
+  MHD_destroy_response (response);
+  return ret;
+}
+
+
+/**
+ * Function to call to handle the request by sending
+ * back static data.
+ *
+ * @param rh context of the handler
+ * @param connection the MHD connection to handle
+ * @param http_status status code to return
+ * @param mime_type content-type to use
+ * @param body response payload
+ * @param body_size number of bytes in @a body
+ * @return MHD result code
+ */
+int
+TALER_MHD_reply_static (struct MHD_Connection *connection,
+                        unsigned int http_status,
+                        const char *mime_type,
+                        const char *body,
+                        size_t *body_size)
+{
+  struct MHD_Response *response;
+  int ret;
+
+  response = MHD_create_response_from_buffer (body_size,
+                                              (void *) body,
+                                              MHD_RESPMEM_PERSISTENT);
+  if (NULL == response)
+  {
+    GNUNET_break (0);
+    return MHD_NO;
+  }
+  TEH_RESPONSE_add_global_headers (response);
+  if (NULL != mime_type)
+    GNUNET_break (MHD_YES ==
+                  MHD_add_response_header (response,
+                                           MHD_HTTP_HEADER_CONTENT_TYPE,
+                                           mime_type));
+  ret = MHD_queue_response (connection,
+                            http_status,
+                            response);
+  MHD_destroy_response (response);
+  return ret;
+}
+
+
 /* end of mhd_responses.c */