commit 021cc96a8f6d3173b789abbedc83fb58b2c14cbb
Author: Christian Grothoff <christian@grothoff.org>
Date: Wed, 26 Nov 2025 14:12:58 +0100
initial import, based on twister
Diffstat:
8 files changed, 2787 insertions(+), 0 deletions(-)
diff --git a/AUTHORS b/AUTHORS
@@ -0,0 +1 @@
+Christian Grothoff
diff --git a/COPYING b/COPYING
@@ -0,0 +1,661 @@
+ GNU AFFERO GENERAL PUBLIC LICENSE
+ Version 3, 19 November 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
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+SUCH DAMAGES.
+
+ 17. Interpretation of Sections 15 and 16.
+
+ If the disclaimer of warranty and limitation of liability provided
+above cannot be given local legal effect according to their terms,
+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+ END OF TERMS AND CONDITIONS
+
+ How to Apply These Terms to Your New Programs
+
+ If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+ To do so, attach the following notices to the program. It is safest
+to attach them to the start of each source file to most effectively
+state the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+ <one line to give the program's name and a brief idea of what it does.>
+ Copyright (C) <year> <name of author>
+
+ This program 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 of the License, or
+ (at your option) any later version.
+
+ This program 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 this program. If not, see <http://www.gnu.org/licenses/>.
+
+Also add information on how to contact you by electronic and paper mail.
+
+ If your software can interact with users remotely through a computer
+network, you should also make sure that it provides a way for users to
+get its source. For example, if your program is a web application, its
+interface could display a "Source" link that leads users to an archive
+of the code. There are many ways you could offer source, and different
+solutions will be better for different programs; see section 13 for the
+specific requirements.
+
+ You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary.
+For more information on this, and how to apply and follow the GNU AGPL, see
+<http://www.gnu.org/licenses/>.
diff --git a/ChangeLog b/ChangeLog
diff --git a/Makefile.am b/Makefile.am
@@ -0,0 +1,8 @@
+# This Makefile.am is in the public domain
+AM_CPPFLAGS = -I$(top_srcdir)/src/include
+
+SUBDIRS = . src doc
+
+ACLOCAL_AMFLAGS = -I m4
+EXTRA_DIST = \
+ AUTHORS
diff --git a/configure.ac b/configure.ac
@@ -0,0 +1,339 @@
+# -*- Autoconf -*-
+# Process this file with autoconf to produce a configure script.
+#
+# This file is part of TALER
+# Copyright (C) 2025 Taler Systems SA
+#
+# TALER 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.
+#
+# 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 General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License along with
+# TALER; see the file COPYING. If not, If not, see <http://www.gnu.org/license>
+#
+#
+AC_PREREQ([2.71])
+AC_INIT([paivana],[0.0.0],[taler-bug@gnunet.org])
+AC_CONFIG_SRCDIR([src/backend/paivana-httpd.c])
+AC_CONFIG_HEADERS([paivana_config.h])
+# support for non-recursive builds
+AM_INIT_AUTOMAKE([subdir-objects 1.9 tar-pax])
+
+# pretty build rules
+AM_SILENT_RULES([yes])
+
+AC_CONFIG_MACRO_DIR([m4])
+
+LT_INIT
+
+# Checks for programs.
+
+AC_PROG_CC
+
+CFLAGS="-Wall $CFLAGS"
+
+# Checks for header files.
+AC_CHECK_HEADERS([stdint.h stdlib.h string.h unistd.h])
+
+
+# Require minimum libgcrypt version
+need_libgcrypt_version=1.6.1
+AC_DEFINE_UNQUOTED([NEED_LIBGCRYPT_VERSION], ["$need_libgcrypt_version"],
+ [minimum version of libgcrypt required])
+AM_PATH_LIBGCRYPT([$need_libgcrypt_version])
+
+
+# Check for GNUnet's libgnunetutil.
+libgnunetutil=0
+AC_MSG_CHECKING([for libgnunetutil])
+AC_ARG_WITH(gnunet,
+ [AS_HELP_STRING([--with-gnunet=PFX], [base of GNUnet installation])],
+ [AC_MSG_RESULT([given as $with_gnunet])],
+ [AC_MSG_RESULT(not given)
+ with_gnunet=yes])
+AS_CASE([$with_gnunet],
+ [yes], [],
+ [no], [AC_MSG_ERROR([--with-gnunet is required])],
+ [LDFLAGS="-L$with_gnunet/lib $LDFLAGS"
+ CPPFLAGS="-I$with_gnunet/include $CPPFLAGS"])
+AC_CHECK_HEADERS([gnunet/gnunet_util_lib.h],
+ [AC_CHECK_LIB([gnunetutil], [GNUNET_SCHEDULER_run], libgnunetutil=1)])
+AS_IF([test $libgnunetutil != 1],
+ [AC_MSG_ERROR([[
+***
+*** You need libgnunetutil to build this program.
+*** This library is part of GNUnet, available at
+*** https://gnunet.org
+*** ]])])
+
+# Check for GNUnet's libgnunetjson.
+libgnunetjson=0
+AC_MSG_CHECKING([for libgnunetjson])
+AC_ARG_WITH(gnunet,
+ [AS_HELP_STRING([--with-gnunet=PFX], [base of GNUnet installation])],
+ [AC_MSG_RESULT([given as $with_gnunet])],
+ [AC_MSG_RESULT(not given)
+ with_gnunet=yes])
+AS_CASE([$with_gnunet],
+ [yes], [],
+ [no], [AC_MSG_ERROR([--with-gnunet is required])],
+ [LDFLAGS="-L$with_gnunet/lib $LDFLAGS"
+ CPPFLAGS="-I$with_gnunet/include $CPPFLAGS"])
+AC_CHECK_HEADERS([gnunet/gnunet_json_lib.h],
+ [AC_CHECK_LIB([gnunetjson], [GNUNET_JSON_parse], libgnunetjson=1)])
+AS_IF([test $libgnunetjson != 1],
+ [AC_MSG_ERROR([[
+***
+*** You need libgnunetjson to build this program.
+*** Make sure you have libjansson installed while
+*** building GNUnet.
+*** ]])])
+
+
+# Save before checking libcurl
+CFLAGS_SAVE=$CFLAGS
+LDFLAGS_SAVE=$LDFLAGS
+LIBS_SAVE=$LIBS
+
+# check for libcurl
+LIBCURL_CHECK_CONFIG(,7.34.0,[curl=1],[curl=0])
+
+# cURL must support CURLINFO_TLS_SESSION, version >= 7.34
+AS_IF([test "x$curl" = x1],[
+ AC_CHECK_HEADER([curl/curl.h],
+ [AC_CHECK_DECLS(CURLINFO_TLS_SESSION,[curl=1],[curl=0],[[#include <curl/curl.h>]])],
+ [curl=0])
+])
+
+# libcurl should be mutually exclusive
+AS_IF([test "$curl" = 1],
+ AM_CONDITIONAL(HAVE_LIBCURL, true)
+ AC_DEFINE([HAVE_LIBCURL],[1],[Have libcurl])
+ [LIBCURL_LIBS="-lcurl"],
+ [AC_MSG_ERROR([FATAL: No libcurl])])
+
+AC_SUBST([LIBCURL_LIBS])
+
+
+# Check for GNUnet's libgnunetcurl.
+libgnunetcurl=0
+AC_MSG_CHECKING([for libgnunetcurl])
+AC_ARG_WITH(gnunet,
+ [AS_HELP_STRING([--with-gnunet=PFX], [base of GNUnet installation])],
+ [AC_MSG_RESULT([given as $with_gnunet])],
+ [AC_MSG_RESULT(not given)
+ with_gnunet=yes])
+AS_CASE([$with_gnunet],
+ [yes], [],
+ [no], [AC_MSG_ERROR([--with-gnunet is required])],
+ [LDFLAGS="-L$with_gnunet/lib $LDFLAGS"
+ CPPFLAGS="-I$with_gnunet/include $CPPFLAGS"])
+AC_CHECK_HEADERS([gnunet/gnunet_curl_lib.h],
+ [AC_CHECK_LIB([gnunetcurl], [GNUNET_CURL_get_select_info], libgnunetcurl=1)])
+AS_IF([test $libgnunetcurl != 1],
+ [AC_MSG_ERROR([[
+***
+*** You need libgnunetcurl to build this program.
+*** Make sure you have libcurl installed while
+*** building GNUnet.
+*** ]])])
+
+
+# check for libmicrohttpd
+microhttpd=0
+AC_MSG_CHECKING([for microhttpd])
+AC_ARG_WITH([microhttpd],
+ [AS_HELP_STRING([--with-microhttpd=PFX], [base of microhttpd installation])],
+ [AC_MSG_RESULT([given as $with_microhttpd])],
+ [AC_MSG_RESULT([not given])
+ with_microhttpd=yes])
+AS_CASE([$with_microhttpd],
+ [yes], [],
+ [no], [AC_MSG_ERROR([--with-microhttpd is required])],
+ [LDFLAGS="-L$with_microhttpd/lib $LDFLAGS"
+ CPPFLAGS="-I$with_microhttpd/include $CPPFLAGS"])
+AC_CHECK_LIB(microhttpd,MHD_start_daemon,
+ [AC_CHECK_HEADER([microhttpd.h],[microhttpd=1])])
+AC_CHECK_DECL([MHD_DAEMON_INFO_CURRENT_CONNECTIONS],,[microhttpd=0],[[#include <microhttpd.h>]])
+AS_IF([test $microhttpd = 0],
+ [AC_MSG_ERROR([[
+***
+*** You need libmicrohttpd >= 0.9.39 to build this program.
+*** ]])])
+
+
+# check for libjansson (Jansson JSON library)
+jansson=0
+AC_MSG_CHECKING([for jansson])
+AC_ARG_WITH([jansson],
+ [AS_HELP_STRING([--with-jansson=PFX], [base of jansson installation])],
+ [AC_MSG_RESULT([given as $with_jansson])],
+ [AC_MSG_RESULT([not given])
+ with_jansson=yes])
+AS_CASE([$with_jansson],
+ [yes], [],
+ [no], [AC_MSG_ERROR([--with-jansson is required])],
+ [LDFLAGS="-L$with_jansson/lib $LDFLAGS"
+ CPPFLAGS="-I$with_jansson/include $CPPFLAGS"])
+AC_CHECK_LIB(jansson,json_pack,
+ [AC_CHECK_HEADER([jansson.h],[jansson=1])])
+AS_IF([test $jansson = 0],
+ [AC_MSG_ERROR([[
+***
+*** You need libjansson to build this program.
+*** ]])])
+
+
+TALER_LIB_LDFLAGS="-export-dynamic -no-undefined"
+TALER_PLUGIN_LDFLAGS="-export-dynamic -avoid-version -module -no-undefined"
+
+AC_SUBST(TALER_LIB_LDFLAGS)
+AC_SUBST(TALER_PLUGIN_LDFLAGS)
+
+CFLAGS_SAVE=$CFLAGS
+LDFLAGS_SAVE=$LDFLAGS
+LIBS_SAVE="$LIBS"
+
+
+# test for zlib
+SAVE_LDFLAGS=$LDFLAGS
+SAVE_CPPFLAGS=$CPPFLAGS
+AC_ARG_WITH(zlib,
+ [ --with-zlib[[=DIR]] use libz in DIR],
+ [AS_IF([test "$withval" = "no"],
+ [AC_MSG_ERROR([Twister requires zlib])],
+ [test "$withval" != "yes"],
+ [
+ Z_DIR=$withval
+ CPPFLAGS="${CPPFLAGS} -I$withval/include"
+ LDFLAGS="${LDFLAGS} -L$withval/lib"
+ ])
+ ])
+AC_CHECK_HEADER(zlib.h,
+ [],
+ [AC_MSG_ERROR([GNUnet requires zlib])])
+AC_CHECK_LIB(z, compress2,
+ [
+ AC_DEFINE([HAVE_ZLIB], [], [Have compression library])
+ if test "x${Z_DIR}" != "x"; then
+ Z_CFLAGS="-I${Z_DIR}/include"
+ Z_LIBS="-L${Z_DIR}/lib -lz"
+ else
+ Z_LIBS="-lz"
+ fi],
+ [AC_MSG_ERROR([Twister requires zlib])])
+AC_SUBST(Z_CFLAGS)
+AC_SUBST(Z_LIBS)
+
+
+# should developer logic be compiled (not-for-production code)?
+AC_MSG_CHECKING(whether to compile developer logic)
+AC_ARG_ENABLE([developer-mode],
+ [AS_HELP_STRING([--enable-developer-mode], [enable compiling developer code])],
+ [enable_developer=${enableval}],
+ [enable_developer=yes])
+AC_MSG_RESULT($enable_developer)
+AM_CONDITIONAL([HAVE_DEVELOPER], [test "x$enable_developer" = "xyes"])
+enable_dev=1
+AS_IF([test "x$enableval" = "xno"], [enable_dev=0])
+# developer-logic requires a more recent MHD than usual.
+AC_CHECK_DECL([MHD_OPTION_NOTIFY_CONNECTION],,[enable_dev=0],[[#include <microhttpd.h>]])
+AC_DEFINE_UNQUOTED([HAVE_DEVELOPER],[$enable_dev],[1 if developer logic is enabled, 0 otherwise])
+
+
+
+# Adam shostack suggests the following for Windows:
+# -D_FORTIFY_SOURCE=2 -fstack-protector-all
+AC_ARG_ENABLE(gcc-hardening,
+ AS_HELP_STRING(--enable-gcc-hardening, enable compiler security checks),
+[if test x$enableval = xyes; then
+ CFLAGS="$CFLAGS -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=2 -fstack-protector-all"
+ CFLAGS="$CFLAGS -fwrapv -fPIE -Wstack-protector"
+ CFLAGS="$CFLAGS --param ssp-buffer-size=1"
+ LDFLAGS="$LDFLAGS -pie"
+fi])
+
+
+# Linker hardening options
+# Currently these options are ELF specific - you can't use this with MacOSX
+AC_ARG_ENABLE(linker-hardening,
+ AS_HELP_STRING(--enable-linker-hardening, enable linker security fixups),
+[if test x$enableval = xyes; then
+ LDFLAGS="$LDFLAGS -z relro -z now"
+fi])
+
+
+# logging
+extra_logging=0
+AC_ARG_ENABLE([logging],
+ AS_HELP_STRING([--enable-logging@<:@=value@:>@],[Enable logging calls. Possible values: yes,no,verbose ('yes' is the default)]),
+ [AS_IF([test "x$enableval" = "xyes"], [],
+ [test "x$enableval" = "xno"], [AC_DEFINE([GNUNET_CULL_LOGGING],[],[Define to cull all logging calls])],
+ [test "x$enableval" = "xverbose"], [extra_logging=1]
+ [test "x$enableval" = "xveryverbose"], [extra_logging=2])
+ ], [])
+AC_DEFINE_UNQUOTED([GNUNET_EXTRA_LOGGING],[$extra_logging],[1 if extra logging is enabled, 2 for very verbose extra logging, 0 otherwise])
+
+# gcov compilation
+AC_MSG_CHECKING(whether to compile with support for code coverage analysis)
+AC_ARG_ENABLE([coverage],
+ AS_HELP_STRING([--enable-coverage],
+ [compile the library with code coverage support]),
+ [use_gcov=${enableval}],
+ [use_gcov=no])
+AC_MSG_RESULT($use_gcov)
+AM_CONDITIONAL([USE_COVERAGE], [test "x$use_gcov" = "xyes"])
+
+# version info
+AC_PATH_PROG(gitcommand, git)
+AC_MSG_CHECKING(for source being under a VCS)
+git_version=
+AS_IF([test ! "X$gitcommand" = "X"],
+[
+ git_version=$(cd $srcdir ; git rev-list --full-history --all --abbrev-commit | head -n 1 2>/dev/null)
+])
+AS_IF([test "X$git_version" = "X"],
+ [
+ vcs_name="no"
+ vcs_version="\"release\""
+ ],
+ [
+ vcs_name="yes, git-svn"
+ vcs_version="\"git-$git_version\""
+ ])
+AC_MSG_RESULT($vcs_name)
+
+AC_MSG_CHECKING(VCS version)
+AC_MSG_RESULT($vcs_version)
+AC_DEFINE_UNQUOTED(VCS_VERSION, [$vcs_version], [VCS revision/hash or tarball version])
+
+
+# Checks for typedefs, structures, and compiler characteristics.
+AC_TYPE_PID_T
+AC_TYPE_SIZE_T
+AC_TYPE_UINT16_T
+AC_TYPE_UINT32_T
+AC_TYPE_UINT64_T
+AC_TYPE_INTMAX_T
+AC_TYPE_UINTMAX_T
+
+# Checks for library functions.
+AC_CHECK_FUNCS([strdup])
+
+
+AC_ARG_ENABLE([[doc]],
+ [AS_HELP_STRING([[--disable-doc]], [do not build any documentation])], ,
+ [enable_doc=yes])
+test "x$enable_doc" = "xno" || enable_doc=yes
+AM_CONDITIONAL([ENABLE_DOC], [test "x$enable_doc" = "xyes"])
+
+
+AC_CONFIG_FILES([Makefile
+ src/Makefile
+ src/backend/Makefile
+ ])
+AC_OUTPUT
diff --git a/src/Makefile.am b/src/Makefile.am
@@ -0,0 +1,4 @@
+# This Makefile.am is in the public domain
+AM_CPPFLAGS = -I$(top_srcdir)/src/include
+
+SUBDIRS = backend
diff --git a/src/backend/Makefile.am b/src/backend/Makefile.am
@@ -0,0 +1,21 @@
+# This Makefile.am is in the public domain
+AM_CPPFLAGS = -I$(top_srcdir)/src/include
+
+if USE_COVERAGE
+ AM_CFLAGS = --coverage -O0
+ XLIB = -lgcov
+endif
+
+bin_PROGRAMS = \
+ paivana-httpd
+
+paivana_httpd_SOURCES = \
+ paivana-httpd.c
+paivana_httpd_LDADD = \
+ $(LIBGCRYPT_LIBS) \
+ -lmicrohttpd \
+ -lcurl \
+ -ljansson \
+ -lgnunetutil \
+ -lgnunetjson \
+ -lz
diff --git a/src/backend/paivana-httpd.c b/src/backend/paivana-httpd.c
@@ -0,0 +1,1753 @@
+/*
+ This file is part of GNU Taler
+ Copyright (C) 2012-2014 GNUnet e.V.
+ Copyright (C) 2018, 2025 Taler Systems SA
+
+ GNU Taler 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.
+
+ GNU 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 General Public License for more details.
+
+ You should have received a copy of the GNU General Public
+ License along with GNU Taler; see the file COPYING. If not,
+ write to the Free Software Foundation, Inc., 51 Franklin
+ Street, Fifth Floor, Boston, MA 02110-1301, USA.
+*/
+
+/**
+ * @author Martin Schanzenbach
+ * @author Christian Grothoff
+ * @author Marcello Stanisci
+ * @file src/backend/paivana-httpd.c
+ * @brief HTTP proxy that acts as a GNU Taler paywall
+ */
+#include "platform.h"
+#include <microhttpd2.h>
+#include <curl/curl.h>
+#include <gnunet/gnunet_util_lib.h>
+#include <microhttpd.h>
+
+
+#define PAIVANA_LOG_INFO(...) \
+ GNUNET_log (GNUNET_ERROR_TYPE_INFO, __VA_ARGS__)
+#define PAIVANA_LOG_DEBUG(...) \
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, __VA_ARGS__)
+#define PAIVANA_LOG_WARNING(...) \
+ GNUNET_log (GNUNET_ERROR_TYPE_WARNING, __VA_ARGS__)
+#define PAIVANA_LOG_ERROR(...) \
+ GNUNET_log (GNUNET_ERROR_TYPE_ERROR, __VA_ARGS__)
+
+#define REQUEST_BUFFER_MAX (1024 * 1024)
+#define UNIX_BACKLOG 500
+
+/**
+ * Log curl error.
+ *
+ * @param level log level
+ * @param fun name of curl_easy-function that gave the error
+ * @param rc return code from curl
+ */
+#define LOG_CURL_EASY(level,fun,rc) \
+ GNUNET_log (level, _ ("%s failed at %s:%d: `%s'\n"), fun, __FILE__, \
+ __LINE__, \
+ curl_easy_strerror (rc))
+
+/* ******** Datastructures for HTTP handling ********** */
+
+
+/**
+ * State machine for HTTP requests (per request).
+ */
+enum RequestState
+{
+ /**
+ * Starting state.
+ */
+ REQUEST_STATE_WITH_MHD = 0,
+
+ /**
+ * We've started receiving upload data from MHD.
+ */
+ REQUEST_STATE_CLIENT_UPLOAD_STARTED,
+
+ /**
+ * Wa have started uploading data to the proxied service.
+ */
+ REQUEST_STATE_PROXY_UPLOAD_STARTED,
+
+ /**
+ * We're done with the upload from MHD.
+ */
+ REQUEST_STATE_CLIENT_UPLOAD_DONE,
+
+ /**
+ * We're done uploading data to the proxied service.
+ */
+ REQUEST_STATE_PROXY_UPLOAD_DONE,
+
+ /**
+ * We've finished uploading data via CURL and can now download.
+ */
+ REQUEST_STATE_PROXY_DOWNLOAD_STARTED,
+
+ /**
+ * We've finished receiving download data from cURL.
+ */
+ REQUEST_STATE_PROXY_DOWNLOAD_DONE
+};
+
+
+/**
+ * A header list
+ */
+struct HttpResponseHeader
+{
+ /**
+ * DLL
+ */
+ struct HttpResponseHeader *next;
+
+ /**
+ * DLL
+ */
+ struct HttpResponseHeader *prev;
+
+ /**
+ * Header type
+ */
+ char *type;
+
+ /**
+ * Header value
+ */
+ char *value;
+};
+
+
+/**
+ * A structure for socks requests
+ */
+struct HttpRequest
+{
+
+ /**
+ * Kept in DLL.
+ */
+ struct HttpRequest *prev;
+
+ /**
+ * Kept in DLL.
+ */
+ struct HttpRequest *next;
+
+ /**
+ * MHD request that triggered us.
+ */
+ struct MHD_Connection *con;
+
+ /**
+ * Client socket read task
+ */
+ struct GNUNET_SCHEDULER_Task *rtask;
+
+ /**
+ * Client socket write task
+ */
+ struct GNUNET_SCHEDULER_Task *wtask;
+
+ /**
+ * Hold the response obtained by modifying the original one.
+ */
+ struct MHD_Response *mod_response;
+
+ /**
+ * MHD response object for this request.
+ */
+ struct MHD_Response *response;
+
+ /**
+ * The URL to fetch
+ */
+ char *url;
+
+ /**
+ * JSON we use to parse payloads (in both directions).
+ */
+ json_t *json;
+
+ /**
+ * Handle to cURL
+ */
+ CURL *curl;
+
+ /**
+ * HTTP request headers for the curl request.
+ */
+ struct curl_slist *headers;
+
+ /**
+ * Headers from response
+ */
+ struct HttpResponseHeader *header_head;
+
+ /**
+ * Headers from response
+ */
+ struct HttpResponseHeader *header_tail;
+
+ /**
+ * Buffer we use for moving data between MHD and
+ * curl (in both directions).
+ */
+ char *io_buf;
+
+ /**
+ * Number of bytes already in the IO buffer.
+ */
+ size_t io_len;
+
+ /**
+ * Number of bytes allocated for the IO buffer.
+ */
+ unsigned int io_size;
+
+ /**
+ * HTTP response code to give to MHD for the response.
+ */
+ unsigned int response_code;
+
+ /**
+ * Request processing state machine.
+ */
+ enum RequestState state;
+
+ /**
+ * Did we suspend MHD processing?
+ */
+ enum GNUNET_GenericReturnValue suspended;
+
+ /**
+ * Did we pause CURL processing?
+ */
+ int curl_paused;
+};
+
+
+/* *********************** Globals **************************** */
+
+/**
+ * The cURL download task (curl multi API).
+ */
+static struct GNUNET_SCHEDULER_Task *curl_download_task;
+
+/**
+ * DLL of active HTTP requests.
+ */
+static struct HttpRequest *hr_head;
+
+/**
+ * DLL of active HTTP requests.
+ */
+static struct HttpRequest *hr_tail;
+
+/**
+ * The cURL multi handle
+ */
+static CURLM *curl_multi;
+
+/**
+ * The daemon handle
+ */
+static struct MHD_Daemon *mhd_daemon;
+
+/**
+ * The task ID
+ */
+static struct GNUNET_SCHEDULER_Task *httpd_task;
+
+/**
+ * Response we return on cURL failures.
+ */
+static struct MHD_Response *curl_failure_response;
+
+/**
+ * Our configuration.
+ */
+static const struct GNUNET_CONFIGURATION_Handle *cfg;
+
+/**
+ * Destination to which HTTP server we forward requests to.
+ * Of the format "http://servername:PORT"
+ */
+static char *target_server_base_url;
+
+
+/* ********************* Global helpers ****************** */
+
+/**
+ * Run MHD now, we have extra data ready for the callback.
+ */
+static void
+run_mhd_now (void);
+
+
+/* *************** HTTP handling with cURL ***************** */
+
+
+/**
+ * Transform _one_ CURL header (gotten from the request) into
+ * MHD format and put it into the response headers list; mostly
+ * copies the headers, but makes special adjustments based on
+ * control requests.
+ *
+ * @param buffer curl buffer with a single
+ * line of header data; not 0-terminated!
+ * @param size curl blocksize
+ * @param nmemb curl blocknumber
+ * @param cls our `struct HttpRequest *`
+ * @return size of processed bytes
+ */
+static size_t
+curl_check_hdr (void *buffer,
+ size_t size,
+ size_t nmemb,
+ void *cls)
+{
+ struct HttpRequest *hr = cls;
+ struct HttpResponseHeader *header;
+ size_t bytes = size * nmemb;
+ char *ndup;
+ const char *hdr_type;
+ char *hdr_val;
+ char *tok;
+
+ /* Raw line is not guaranteed to be null-terminated. */
+ ndup = GNUNET_malloc (bytes + 1);
+ memcpy (ndup,
+ buffer,
+ bytes);
+ ndup[bytes] = '\0';
+
+ hdr_type = strtok (ndup, ":");
+
+ if (NULL == hdr_type)
+ {
+ GNUNET_free (ndup);
+ return bytes;
+ }
+ hdr_val = strtok (NULL, "");
+ if (NULL == hdr_val)
+ {
+ GNUNET_free (ndup);
+ return bytes;
+ }
+ if (' ' == *hdr_val)
+ hdr_val++;
+
+ /* MHD does not allow certain characters in values,
+ * remove those, plus those could alter strings matching. */
+ if (NULL != (tok = strchr (hdr_val, '\n')))
+ *tok = '\0';
+ if (NULL != (tok = strchr (hdr_val, '\r')))
+ *tok = '\0';
+ if (NULL != (tok = strchr (hdr_val, '\t')))
+ *tok = '\0';
+
+ PAIVANA_LOG_DEBUG ("Parsed line: '%s: %s'\n",
+ hdr_type,
+ hdr_val);
+
+ /* Skip "Content-length:" header as it will be wrong, given
+ that we are man-in-the-middling the connection */
+ if (0 == strcasecmp (hdr_type,
+ MHD_HTTP_HEADER_CONTENT_LENGTH))
+ {
+ GNUNET_free (ndup);
+ return bytes;
+ }
+ /* Skip "Connection: Keep-Alive" header, it will be
+ done by MHD if possible */
+ if ( (0 == strcasecmp (hdr_type,
+ MHD_HTTP_HEADER_CONNECTION)) &&
+ (0 == strcasecmp (hdr_val,
+ "Keep-Alive")) )
+ {
+ GNUNET_free (ndup);
+ return bytes;
+ }
+ if (0 != strlen (hdr_val)) /* Rely in MHD to set those */
+ {
+ header = GNUNET_new (struct HttpResponseHeader);
+ header->type = GNUNET_strdup (hdr_type);
+ header->value = GNUNET_strdup (hdr_val);
+ GNUNET_CONTAINER_DLL_insert (hr->header_head,
+ hr->header_tail,
+ header);
+ }
+ GNUNET_free (ndup);
+ return bytes;
+}
+
+
+/**
+ * Create the MHD response with CURL's as starting base;
+ * mainly set the response code and parses the response into
+ * JSON, if it is such.
+ *
+ * @param hr pointer to where to store the new data. Despite
+ * its name, the struct contains response data as well.
+ * @return #GNUNET_OK if it succeeds.
+ */
+static enum GNUNET_GenericReturnValue
+create_mhd_response_from_hr (struct HttpRequest *hr)
+{
+ long resp_code;
+ json_error_t error;
+
+ if (NULL != hr->response)
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+ "Response already set!\n");
+ return GNUNET_SYSERR;
+ }
+ GNUNET_break (CURLE_OK ==
+ curl_easy_getinfo (hr->curl,
+ CURLINFO_RESPONSE_CODE,
+ &resp_code));
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Creating MHD response with code %u\n",
+ (unsigned int) resp_code);
+ hr->response_code = resp_code;
+ /* Note, will be NULL if io_buf does not represent
+ * a JSON value. */
+ hr->json = json_loadb (hr->io_buf,
+ hr->io_len,
+ JSON_DECODE_ANY,
+ &error);
+ if (GNUNET_YES == hr->suspended)
+ {
+ MHD_resume_connection (hr->con);
+ hr->suspended = GNUNET_NO;
+ }
+ run_mhd_now ();
+ return GNUNET_OK;
+}
+
+
+/**
+ * Handle response payload data from cURL.
+ * Copies it into our `io_buf` to make it available to MHD.
+ *
+ * @param ptr pointer to the data
+ * @param size number of blocks of data
+ * @param nmemb blocksize
+ * @param ctx our `struct HttpRequest *`
+ * @return number of bytes handled
+ */
+static size_t
+curl_download_cb (void *ptr,
+ size_t size,
+ size_t nmemb,
+ void *ctx)
+{
+ struct HttpRequest *hr = ctx;
+ size_t total = size * nmemb;
+
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Curl download proceeding\n");
+
+ if (REQUEST_STATE_PROXY_UPLOAD_STARTED == hr->state)
+ {
+ /* Web server started with response before we finished
+ the upload. In this case, current libcurl decides
+ to NOT complete the upload, so we should jump in the
+ state machine to process the download, dropping the
+ rest of the upload. This should only really happen
+ with uploads without "Expect: 100 Continue" and
+ Web servers responding with an error (i.e. upload
+ not allowed) */hr->state = REQUEST_STATE_PROXY_DOWNLOAD_STARTED;
+ GNUNET_log
+ (GNUNET_ERROR_TYPE_INFO,
+ "Stopping %u byte upload: we are already downloading...\n",
+ (unsigned int) hr->io_len);
+ hr->io_len = 0;
+ }
+
+ if (REQUEST_STATE_PROXY_DOWNLOAD_STARTED != hr->state)
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Download callback goes to sleep\n");
+ hr->curl_paused = GNUNET_YES;
+ return CURL_WRITEFUNC_PAUSE;
+ }
+ GNUNET_assert (REQUEST_STATE_PROXY_DOWNLOAD_STARTED ==
+ hr->state);
+ if (hr->io_size - hr->io_len < total)
+ {
+ GNUNET_assert (total + hr->io_size >= total);
+ GNUNET_assert (hr->io_size * 2 + 1024 > hr->io_size);
+ GNUNET_array_grow (hr->io_buf,
+ hr->io_size,
+ GNUNET_MAX (total + hr->io_len,
+ hr->io_size * 2 + 1024));
+ }
+ GNUNET_memcpy (&hr->io_buf[hr->io_len],
+ ptr,
+ total);
+ hr->io_len += total;
+ return total;
+}
+
+
+/**
+ * Ask cURL for the select() sets and schedule cURL operations.
+ */
+static void
+curl_download_prepare (void);
+
+
+/**
+ * cURL callback for uploaded (PUT/POST) data.
+ * Copies from our `io_buf` to make it available to cURL.
+ *
+ * @param buf where to write the data
+ * @param size number of bytes per member
+ * @param nmemb number of members available in @a buf
+ * @param cls our `struct HttpRequest` that generated the data
+ * @return number of bytes copied to @a buf
+ */
+static size_t
+curl_upload_cb (void *buf,
+ size_t size,
+ size_t nmemb,
+ void *cls)
+{
+ struct HttpRequest *hr = cls;
+ size_t len = size * nmemb;
+ size_t to_copy;
+
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Upload cb is working...\n");
+
+ if ( (REQUEST_STATE_PROXY_DOWNLOAD_STARTED == hr->state) ||
+ (REQUEST_STATE_PROXY_DOWNLOAD_DONE == hr->state) )
+ {
+ GNUNET_log
+ (GNUNET_ERROR_TYPE_INFO,
+ "Upload cb aborts: we are already downloading...\n");
+ return CURL_READFUNC_ABORT;
+ }
+
+ if ( (0 == hr->io_len) &&
+ (REQUEST_STATE_PROXY_UPLOAD_STARTED == hr->state) )
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Pausing CURL UPLOAD, need more data\n");
+ return CURL_READFUNC_PAUSE;
+ }
+
+ /**
+ * We got rescheduled because the download callback was asleep.
+ * FIXME: can this block be eliminated and the unpausing being
+ * moved in the last block where we return zero as well?
+ */
+ if ( (0 == hr->io_len) &&
+ (REQUEST_STATE_PROXY_DOWNLOAD_STARTED == hr->state) )
+ {
+ if (GNUNET_YES == hr->curl_paused)
+ {
+ hr->curl_paused = GNUNET_NO;
+ curl_easy_pause (hr->curl,
+ CURLPAUSE_CONT);
+ }
+ curl_download_prepare ();
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Completed CURL UPLOAD\n");
+ return 0; /* upload finished, can now download */
+ }
+ to_copy = GNUNET_MIN (hr->io_len,
+ len);
+ GNUNET_memcpy (buf,
+ hr->io_buf,
+ to_copy);
+ /* shift remaining data back to the beginning of the buffer. */
+ memmove (hr->io_buf,
+ &hr->io_buf[to_copy],
+ hr->io_len - to_copy);
+ hr->io_len -= to_copy;
+ if (0 == hr->io_len)
+ {
+ hr->state = REQUEST_STATE_PROXY_DOWNLOAD_STARTED;
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Completed CURL UPLOAD\n");
+ }
+ return to_copy;
+}
+
+
+/* ************** helper functions ************* */
+
+/**
+ * Extract the hostname from a complete URL.
+ *
+ * @param url full fledged URL
+ *
+ * @return pointer to the 0-terminated hostname, to be freed
+ * by the caller.
+ */
+static char *
+build_host_header (const char *url)
+{
+ #define MARKER "://"
+
+ char *header;
+ char *end;
+ char *hostname;
+ char *dup = GNUNET_strdup (url);
+
+ hostname = strstr (dup, MARKER);
+ hostname += 3;
+
+ end = strchrnul (hostname, '/');
+ *end = '\0';
+
+ GNUNET_asprintf (&header,
+ "Host: %s",
+ hostname);
+
+ GNUNET_free (dup);
+ return header;
+}
+
+
+/* ************** main loop of cURL interaction ************* */
+
+
+/**
+ * Task that is run when we are ready to receive more data
+ * from curl
+ *
+ * @param cls closure
+ */
+static void
+curl_task_download (void *cls);
+
+
+/**
+ * Ask cURL for the select() sets and schedule cURL operations.
+ */
+static void
+curl_download_prepare ()
+{
+ CURLMcode mret;
+ fd_set rs;
+ fd_set ws;
+ fd_set es;
+ int max;
+ struct GNUNET_NETWORK_FDSet *grs;
+ struct GNUNET_NETWORK_FDSet *gws;
+ long to;
+ struct GNUNET_TIME_Relative rtime;
+
+ if (NULL != curl_download_task)
+ {
+ GNUNET_SCHEDULER_cancel (curl_download_task);
+ curl_download_task = NULL;
+ }
+ max = -1;
+ FD_ZERO (&rs);
+ FD_ZERO (&ws);
+ FD_ZERO (&es);
+ if (CURLM_OK != (mret = curl_multi_fdset (curl_multi,
+ &rs,
+ &ws,
+ &es,
+ &max)))
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+ "%s failed at %s:%d: `%s'\n",
+ "curl_multi_fdset",
+ __FILE__,
+ __LINE__,
+ curl_multi_strerror (mret));
+ return;
+ }
+ to = -1;
+ GNUNET_break (CURLM_OK ==
+ curl_multi_timeout (curl_multi,
+ &to));
+ if (-1 == to)
+ rtime = GNUNET_TIME_UNIT_FOREVER_REL;
+ else
+ rtime = GNUNET_TIME_relative_multiply
+ (GNUNET_TIME_UNIT_MILLISECONDS, to);
+ if (-1 != max)
+ {
+ grs = GNUNET_NETWORK_fdset_create ();
+ gws = GNUNET_NETWORK_fdset_create ();
+ GNUNET_NETWORK_fdset_copy_native (grs,
+ &rs,
+ max + 1);
+ GNUNET_NETWORK_fdset_copy_native (gws,
+ &ws,
+ max + 1);
+ curl_download_task
+ = GNUNET_SCHEDULER_add_select (
+ GNUNET_SCHEDULER_PRIORITY_DEFAULT,
+ rtime,
+ grs, gws,
+ &curl_task_download,
+ curl_multi);
+ GNUNET_NETWORK_fdset_destroy (gws);
+ GNUNET_NETWORK_fdset_destroy (grs);
+ }
+ else
+ {
+ curl_download_task = GNUNET_SCHEDULER_add_delayed
+ (rtime,
+ &curl_task_download,
+ curl_multi);
+ }
+}
+
+
+/**
+ * Task that is run when we are ready to receive
+ * more data from curl.
+ *
+ * @param cls closure, usually NULL.
+ */
+static void
+curl_task_download (void *cls)
+{
+ int running;
+ int msgnum;
+ struct CURLMsg *msg;
+ CURLMcode mret;
+ struct HttpRequest *hr;
+
+ (void) cls;
+ curl_download_task = NULL;
+ do
+ {
+ running = 0;
+ mret = curl_multi_perform (curl_multi,
+ &running);
+ while (NULL != (msg = curl_multi_info_read (curl_multi,
+ &msgnum)))
+ {
+ GNUNET_break
+ (CURLE_OK == curl_easy_getinfo
+ (msg->easy_handle,
+ CURLINFO_PRIVATE,
+ (char **) &hr));
+
+ if (NULL == hr)
+ {
+ GNUNET_break (0);
+ continue;
+ }
+ switch (msg->msg)
+ {
+ case CURLMSG_NONE:
+ /* documentation says this is not used */
+ GNUNET_break (0);
+ break;
+ case CURLMSG_DONE:
+ switch (msg->data.result)
+ {
+ case CURLE_OK:
+ case CURLE_GOT_NOTHING:
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "CURL download completed.\n");
+ hr->state = REQUEST_STATE_PROXY_DOWNLOAD_DONE;
+ if (NULL == hr->response)
+ GNUNET_assert (GNUNET_OK ==
+ create_mhd_response_from_hr (hr));
+ break;
+ default:
+ GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
+ "Download curl failed: %s\n",
+ curl_easy_strerror (msg->data.result));
+ /* FIXME: indicate error somehow?
+ * close MHD connection badly as well? */
+ hr->state = REQUEST_STATE_PROXY_DOWNLOAD_DONE;
+ if (GNUNET_YES == hr->suspended)
+ {
+ MHD_resume_connection (hr->con);
+ hr->suspended = GNUNET_NO;
+ }
+ run_mhd_now ();
+ break;
+ }
+ if (NULL == hr->response)
+ hr->response = curl_failure_response;
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Curl request for `%s' finished (got the response)\n",
+ hr->url);
+ run_mhd_now ();
+ break;
+ case CURLMSG_LAST:
+ /* documentation says this is not used */
+ GNUNET_break (0);
+ break;
+ default:
+ /* unexpected status code */
+ GNUNET_break (0);
+ break;
+ }
+ }
+ ;
+ } while (mret == CURLM_CALL_MULTI_PERFORM);
+ if (CURLM_OK != mret)
+ GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+ "%s failed at %s:%d: `%s'\n",
+ "curl_multi_perform",
+ __FILE__,
+ __LINE__,
+ curl_multi_strerror (mret));
+ if (0 == running)
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Suspending cURL multi loop,"
+ " no more events pending\n");
+ return; /* nothing more in progress */
+ }
+ curl_download_prepare ();
+}
+
+
+/* *************** MHD response generation ***************** */
+
+
+/**
+ * Main MHD callback for handling requests.
+ *
+ * @param cls unused
+ * @param con MHD connection handle
+ * @param url the url in the request
+ * @param meth the HTTP method used ("GET", "PUT", etc.)
+ * @param ver 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
+ * @a upload_data provided; the method must update this
+ * value to the number of bytes NOT processed;
+ * @param con_cls pointer to location where we store the
+ * 'struct Request'
+ * @return #MHD_YES if the connection was handled successfully,
+ * #MHD_NO if the socket must be closed due to a serious
+ * error while handling the request
+ */
+static MHD_RESULT
+create_response (void *cls,
+ struct MHD_Connection *con,
+ const char *url,
+ const char *meth,
+ const char *ver,
+ const char *upload_data,
+ size_t *upload_data_size,
+ void **con_cls)
+{
+ struct HttpRequest *hr = *con_cls;
+
+ (void) cls;
+ (void) url;
+
+ if (NULL == hr)
+ {
+ GNUNET_break (0);
+ return MHD_NO;
+ }
+
+ if (REQUEST_STATE_WITH_MHD == hr->state)
+ {
+ hr->state = REQUEST_STATE_CLIENT_UPLOAD_STARTED;
+ /* TODO: hacks for 100 continue suppression would go here! */
+ return MHD_YES;
+ }
+
+ /* continuing to process request */
+ if (0 != *upload_data_size)
+ {
+ GNUNET_assert
+ (REQUEST_STATE_CLIENT_UPLOAD_STARTED == hr->state);
+
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Processing %u bytes UPLOAD\n",
+ (unsigned int) *upload_data_size);
+
+ /* Grow the buffer if remaining space isn't enough. */
+ if (hr->io_size - hr->io_len < *upload_data_size)
+ {
+ /* How can this assertion be false? */
+ GNUNET_assert (hr->io_size * 2 + 1024 > hr->io_size);
+ /* This asserts that upload_data_size > 0, ? */
+ GNUNET_assert (*upload_data_size + hr->io_len > hr->io_len);
+
+ GNUNET_array_grow (hr->io_buf,
+ hr->io_size,
+ GNUNET_MAX
+ (hr->io_size * 2 + 1024,
+ *upload_data_size + hr->io_len));
+ }
+
+ /* Finally copy upload data. */
+ GNUNET_memcpy (&hr->io_buf[hr->io_len],
+ upload_data,
+ *upload_data_size);
+
+ hr->io_len += *upload_data_size;
+ *upload_data_size = 0;
+
+ return MHD_YES;
+ }
+
+ /* Upload (*from the client*) finished or just a without-body
+ * request. */
+ if (REQUEST_STATE_CLIENT_UPLOAD_STARTED == hr->state)
+ {
+ hr->state = REQUEST_STATE_CLIENT_UPLOAD_DONE;
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Finished processing UPLOAD\n");
+ }
+
+ /* generate curl request to the proxied service. */
+ if (NULL == hr->curl)
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Generating curl request\n");
+ hr->curl = curl_easy_init ();
+ if (NULL == hr->curl)
+ {
+ PAIVANA_LOG_ERROR ("Could not init the curl handle\n");
+ return MHD_queue_response (con,
+ MHD_HTTP_INTERNAL_SERVER_ERROR,
+ curl_failure_response);
+ }
+
+ /* No need to check whether we're POSTing or PUTting.
+ * If not needed, one of the following values will be
+ * ignored.*/
+ curl_easy_setopt (hr->curl,
+ CURLOPT_POSTFIELDSIZE,
+ hr->io_len);
+ curl_easy_setopt (hr->curl,
+ CURLOPT_INFILESIZE,
+ hr->io_len);
+ curl_easy_setopt (hr->curl,
+ CURLOPT_HEADERFUNCTION,
+ &curl_check_hdr);
+ curl_easy_setopt (hr->curl,
+ CURLOPT_HEADERDATA,
+ hr);
+ curl_easy_setopt (hr->curl,
+ CURLOPT_FOLLOWLOCATION,
+ 0);
+ curl_easy_setopt (hr->curl,
+ CURLOPT_CONNECTTIMEOUT,
+ 600L);
+ curl_easy_setopt (hr->curl,
+ CURLOPT_TIMEOUT,
+ 600L);
+ curl_easy_setopt (hr->curl,
+ CURLOPT_NOSIGNAL,
+ 1L);
+ curl_easy_setopt (hr->curl,
+ CURLOPT_PRIVATE,
+ hr);
+ curl_easy_setopt (hr->curl,
+ CURLOPT_VERBOSE,
+ 0);
+
+ curl_easy_setopt (hr->curl,
+ CURLOPT_READFUNCTION,
+ &curl_upload_cb);
+
+ curl_easy_setopt (hr->curl,
+ CURLOPT_READDATA,
+ hr);
+
+ curl_easy_setopt (hr->curl,
+ CURLOPT_WRITEFUNCTION,
+ &curl_download_cb);
+
+ curl_easy_setopt (hr->curl,
+ CURLOPT_WRITEDATA,
+ hr);
+ {
+ char *curlurl;
+ char *host_hdr;
+
+ GNUNET_asprintf (&curlurl,
+ "%s%s",
+ target_server_base_url,
+ hr->url);
+ curl_easy_setopt (hr->curl,
+ CURLOPT_URL,
+ curlurl);
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Forwarding request to: %s\n",
+ curlurl);
+ GNUNET_free (curlurl);
+
+ host_hdr = build_host_header (target_server_base_url);
+ PAIVANA_LOG_DEBUG ("Faking the host header, %s\n",
+ host_hdr);
+ hr->headers = curl_slist_append (hr->headers,
+ host_hdr);
+ GNUNET_free (host_hdr);
+ }
+
+ if (0 == strcasecmp (meth,
+ MHD_HTTP_METHOD_PUT))
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Crafting a CURL PUT request\n");
+
+ curl_easy_setopt (hr->curl,
+ CURLOPT_UPLOAD,
+ 1L);
+ hr->state = REQUEST_STATE_PROXY_UPLOAD_STARTED;
+
+ }
+ else if (0 == strcasecmp (meth,
+ MHD_HTTP_METHOD_POST))
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Crafting a CURL POST request\n");
+ curl_easy_setopt (hr->curl,
+ CURLOPT_POST,
+ 1L);
+ curl_easy_setopt (hr->curl,
+ CURLOPT_VERBOSE,
+ 1L);
+ hr->state = REQUEST_STATE_PROXY_UPLOAD_STARTED;
+
+ }
+ else if (0 == strcasecmp (meth,
+ MHD_HTTP_METHOD_HEAD))
+ {
+ hr->state = REQUEST_STATE_PROXY_DOWNLOAD_STARTED;
+ curl_easy_setopt (hr->curl,
+ CURLOPT_NOBODY,
+ 1L);
+ }
+ else if (0 == strcasecmp (meth,
+ MHD_HTTP_METHOD_OPTIONS))
+ {
+ hr->state = REQUEST_STATE_PROXY_DOWNLOAD_STARTED;
+ curl_easy_setopt (hr->curl,
+ CURLOPT_CUSTOMREQUEST,
+ "OPTIONS");
+ }
+ else if (0 == strcasecmp (meth,
+ MHD_HTTP_METHOD_GET))
+ {
+ hr->state = REQUEST_STATE_PROXY_DOWNLOAD_STARTED;
+ curl_easy_setopt (hr->curl,
+ CURLOPT_HTTPGET,
+ 1L);
+ }
+ else
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
+ "Unsupported HTTP method `%s'\n",
+ meth);
+ curl_easy_cleanup (hr->curl);
+ hr->curl = NULL;
+ return MHD_NO;
+ }
+
+ if (0 == strcasecmp (ver,
+ MHD_HTTP_VERSION_1_0))
+ {
+ curl_easy_setopt (hr->curl,
+ CURLOPT_HTTP_VERSION,
+ CURL_HTTP_VERSION_1_0);
+ }
+ else if (0 == strcasecmp (ver,
+ MHD_HTTP_VERSION_1_1))
+ {
+ curl_easy_setopt (hr->curl,
+ CURLOPT_HTTP_VERSION,
+ CURL_HTTP_VERSION_1_1);
+ }
+ else
+ {
+ curl_easy_setopt (hr->curl,
+ CURLOPT_HTTP_VERSION,
+ CURL_HTTP_VERSION_NONE);
+ }
+
+ if (CURLM_OK != curl_multi_add_handle (curl_multi,
+ hr->curl))
+ {
+ GNUNET_break (0);
+ curl_easy_cleanup (hr->curl);
+ hr->curl = NULL;
+ return MHD_NO;
+ }
+
+ MHD_get_connection_values (con,
+ MHD_HEADER_KIND,
+ &con_val_iter,
+ hr);
+
+ curl_easy_setopt (hr->curl,
+ CURLOPT_HTTPHEADER,
+ hr->headers);
+ curl_download_prepare ();
+
+ return MHD_YES;
+ }
+
+ if (REQUEST_STATE_PROXY_DOWNLOAD_DONE != hr->state)
+ {
+ GNUNET_assert (GNUNET_NO == hr->suspended);
+ MHD_suspend_connection (con);
+ hr->suspended = GNUNET_YES;
+ return MHD_YES; /* wait for curl */
+ }
+
+ GNUNET_assert (REQUEST_STATE_PROXY_DOWNLOAD_DONE == hr->state);
+ if (0 != hack_response_code)
+ {
+ hr->response_code = hack_response_code;
+ hack_response_code = 0; /* reset for next request */
+ }
+
+ for (struct HttpResponseHeader *header = hr->header_head;
+ NULL != header;
+ header = header->next)
+ {
+ const char *value = header->value;
+
+ if ((NULL != modify_header_dl) &&
+ (0 == strcmp (header->type,
+ modify_header_dl)))
+ {
+ value = modify_value;
+ }
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Adding MHD response header %s->%s\n",
+ header->type,
+ value);
+ GNUNET_break (MHD_YES ==
+ MHD_add_response_header (hr->response,
+ header->type,
+ value));
+ }
+ run_mhd_now ();
+
+ return MHD_queue_response (con,
+ hr->response_code,
+ hr->response);
+}
+
+
+/* ************ MHD HTTP setup and event loop *************** */
+
+
+/**
+ * Function called when MHD decides that we
+ * are done with a request.
+ *
+ * @param cls NULL
+ * @param connection connection handle
+ * @param con_cls value as set by the last call to
+ * the MHD_AccessHandlerCallback, should be
+ * our `struct HttpRequest *` (set by `create_response()`)
+ * @param toe reason for request termination (ignored)
+ */
+static void
+mhd_completed_cb (void *cls,
+ struct MHD_Connection *connection,
+ void **con_cls,
+ enum MHD_RequestTerminationCode toe)
+{
+ struct HttpRequest *hr = *con_cls;
+ struct HttpResponseHeader *header;
+
+ (void) cls;
+ (void) connection;
+ if (NULL == hr)
+ return;
+ if (MHD_REQUEST_TERMINATED_COMPLETED_OK != toe)
+ GNUNET_log (GNUNET_ERROR_TYPE_INFO,
+ "MHD encountered error handling request: %d\n",
+ toe);
+ if (NULL != hr->curl)
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Resetting cURL handle\n");
+ curl_multi_remove_handle (curl_multi,
+ hr->curl);
+ curl_easy_cleanup (hr->curl);
+ hr->curl = NULL;
+ hr->io_len = 0;
+ }
+ if (NULL != hr->headers)
+ {
+ curl_slist_free_all (hr->headers);
+ hr->headers = NULL;
+ }
+ if ( (NULL != hr->response) &&
+ (curl_failure_response != hr->response) )
+ /* Destroy non-error responses... (?) */
+ MHD_destroy_response (hr->response);
+
+ for (header = hr->header_head;
+ header != NULL;
+ header = hr->header_head)
+ {
+ GNUNET_CONTAINER_DLL_remove (hr->header_head,
+ hr->header_tail,
+ header);
+ GNUNET_free (header->type);
+ GNUNET_free (header->value);
+ GNUNET_free (header);
+ }
+
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Proxying of '%s' completely done\n",
+ hr->url);
+
+ GNUNET_free (hr->url);
+ GNUNET_free (hr->io_buf);
+ GNUNET_CONTAINER_DLL_remove (hr_head,
+ hr_tail,
+ hr);
+ GNUNET_free (hr);
+ *con_cls = NULL;
+}
+
+
+/**
+ * Function called when MHD first processes an incoming connection.
+ * Gives us the respective URI information.
+ *
+ * We use this to associate the `struct MHD_Connection` with our
+ * internal `struct HttpRequest` data structure (by checking
+ * for matching sockets).
+ *
+ * @param cls the HTTP server handle (a `struct MhdHttpList`)
+ * @param url the URL that is being requested
+ * @param connection MHD connection object for the request
+ * @return the `struct HttpRequest` that this @a connection is for
+ */
+static void *
+mhd_log_callback (void *cls,
+ const char *url,
+ struct MHD_Connection *connection)
+{
+ struct HttpRequest *hr;
+ const union MHD_ConnectionInfo *ci;
+
+ (void) cls;
+ ci = MHD_get_connection_info (connection,
+ MHD_CONNECTION_INFO_SOCKET_CONTEXT);
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Processing %s\n",
+ url);
+ if (NULL == ci)
+ {
+ GNUNET_break (0);
+ return NULL;
+ }
+
+ hr = GNUNET_new (struct HttpRequest);
+ hr->con = connection;
+ hr->url = GNUNET_strdup (url);
+ GNUNET_CONTAINER_DLL_insert (hr_head,
+ hr_tail,
+ hr);
+ return hr;
+}
+
+
+/**
+ * Kill the MHD daemon.
+ */
+static void
+kill_httpd (void)
+{
+ MHD_stop_daemon (mhd_daemon);
+ mhd_daemon = NULL;
+ if (NULL != httpd_task)
+ {
+ GNUNET_SCHEDULER_cancel (httpd_task);
+ httpd_task = NULL;
+ }
+}
+
+
+/**
+ * Task run whenever HTTP server operations are pending.
+ *
+ * @param cls the `struct MhdHttpList *`
+ * of the daemon that is being run
+ */
+static void
+do_httpd (void *cls);
+
+
+/**
+ * Schedule MHD. This function should be called initially when an
+ * MHD is first getting its client socket, and will then
+ * automatically always be called later whenever there is work to
+ * be done.
+ */
+static void
+schedule_httpd (void)
+{
+ fd_set rs;
+ fd_set ws;
+ fd_set es;
+ struct GNUNET_NETWORK_FDSet *wrs;
+ struct GNUNET_NETWORK_FDSet *wws;
+ int max;
+ int haveto;
+ MHD_UNSIGNED_LONG_LONG timeout;
+ struct GNUNET_TIME_Relative tv;
+
+ FD_ZERO (&rs);
+ FD_ZERO (&ws);
+ FD_ZERO (&es);
+ max = -1;
+ if (MHD_YES !=
+ MHD_get_fdset (mhd_daemon,
+ &rs,
+ &ws,
+ &es,
+ &max))
+ {
+ kill_httpd ();
+ return;
+ }
+ haveto = MHD_get_timeout (mhd_daemon,
+ &timeout);
+ if (MHD_YES == haveto)
+ tv.rel_value_us = (uint64_t) timeout * 1000LL;
+ else
+ tv = GNUNET_TIME_UNIT_FOREVER_REL;
+ if (-1 != max)
+ {
+ wrs = GNUNET_NETWORK_fdset_create ();
+ wws = GNUNET_NETWORK_fdset_create ();
+ GNUNET_NETWORK_fdset_copy_native (wrs,
+ &rs,
+ max + 1);
+ GNUNET_NETWORK_fdset_copy_native (wws,
+ &ws,
+ max + 1);
+ }
+ else
+ {
+ wrs = NULL;
+ wws = NULL;
+ }
+ if (NULL != httpd_task)
+ {
+ GNUNET_SCHEDULER_cancel (httpd_task);
+ httpd_task = NULL;
+ }
+ httpd_task =
+ GNUNET_SCHEDULER_add_select (GNUNET_SCHEDULER_PRIORITY_DEFAULT,
+ tv,
+ wrs,
+ wws,
+ &do_httpd,
+ NULL);
+ if (NULL != wrs)
+ GNUNET_NETWORK_fdset_destroy (wrs);
+ if (NULL != wws)
+ GNUNET_NETWORK_fdset_destroy (wws);
+}
+
+
+/**
+ * Task run whenever HTTP server operations are pending.
+ *
+ * @param cls NULL
+ */
+static void
+do_httpd (void *cls)
+{
+ (void) cls;
+ httpd_task = NULL;
+ MHD_run (mhd_daemon);
+ schedule_httpd ();
+}
+
+
+/**
+ * Run MHD now, we have extra data ready for the callback.
+ */
+static void
+run_mhd_now (void)
+{
+ if (NULL != httpd_task)
+ GNUNET_SCHEDULER_cancel (httpd_task);
+ httpd_task = GNUNET_SCHEDULER_add_now (&do_httpd,
+ NULL);
+}
+
+
+/* *************** General / main code *************** */
+
+
+/**
+ * Task run on shutdown
+ *
+ * @param cls closure
+ */
+static void
+do_shutdown (void *cls)
+{
+ (void) cls;
+ GNUNET_log (GNUNET_ERROR_TYPE_INFO,
+ "Shutting down...\n");
+ /* MHD requires resuming before destroying the daemons */
+ for (struct HttpRequest *hr = hr_head;
+ NULL != hr;
+ hr = hr->next)
+ {
+ if (GNUNET_YES == hr->suspended)
+ {
+ hr->suspended = GNUNET_NO;
+ MHD_resume_connection (hr->con);
+ }
+ }
+ kill_httpd ();
+ if (NULL != curl_multi)
+ {
+ curl_multi_cleanup (curl_multi);
+ curl_multi = NULL;
+ }
+ if (NULL != curl_download_task)
+ {
+ GNUNET_SCHEDULER_cancel (curl_download_task);
+ curl_download_task = NULL;
+ }
+ GNUNET_free (target_server_base_url);
+}
+
+
+/**
+ * Connect to a unix domain socket.
+ *
+ * @param path the IPC path
+ * @param mode the IPC path mode
+ * @return the file descriptor of the connection.
+ */
+static int
+open_unix_path (const char *path,
+ mode_t mode)
+{
+
+ struct GNUNET_NETWORK_Handle *nh;
+ struct sockaddr_un *un;
+ int fd;
+
+ if (sizeof (un->sun_path) <= strlen (path))
+ {
+ fprintf (stderr,
+ "path `%s' too long\n",
+ path);
+ return -1;
+ }
+ GNUNET_log (GNUNET_ERROR_TYPE_INFO,
+ "Creating listen socket '%s' with mode %o\n",
+ path,
+ mode);
+
+ if (GNUNET_OK !=
+ GNUNET_DISK_directory_create_for_file (path))
+ {
+ GNUNET_log_strerror_file (GNUNET_ERROR_TYPE_ERROR,
+ "mkdir",
+ path);
+ }
+
+ un = GNUNET_new (struct sockaddr_un);
+ un->sun_family = AF_UNIX;
+
+ strncpy (un->sun_path,
+ 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 (path,
+ 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",
+ path,
+ mode);
+ fd = GNUNET_NETWORK_get_fd (nh);
+ GNUNET_NETWORK_socket_free_memory_only_ (nh);
+ return fd;
+}
+
+
+/**
+ * Crawl the configuration file and extracts the serving
+ * method, TCP vs IPC, and the respective details (port/path/mode)
+ *
+ * @param ccfg configuration handle.
+ * @param port[out] port number to use
+ * @param path[out] unix path for IPC.
+ * @param mode[out] mode string for @a path.
+ * @return #GNUNET_SYSERR if the parsing didn't succeed.
+ */
+static int
+parse_serving_mean (const struct GNUNET_CONFIGURATION_Handle *ccfg,
+ uint16_t *port,
+ char **path,
+ mode_t *mode)
+{
+
+ const char *serve;
+ const char *choices[] = {"tcp", "unix", NULL};
+ char *modestring;
+ unsigned long long port_ull;
+
+
+ if (GNUNET_OK !=
+ GNUNET_CONFIGURATION_get_value_choice (ccfg,
+ "paivana",
+ "SERVE",
+ choices,
+ &serve))
+ {
+ GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR,
+ "paivana",
+ "SERVE");
+ return GNUNET_SYSERR;
+ }
+
+ if (0 == strcmp ("tcp", serve))
+ {
+ *path = NULL;
+
+ if (GNUNET_OK !=
+ GNUNET_CONFIGURATION_get_value_number (ccfg,
+ "paivana",
+ "HTTP_PORT",
+ &port_ull))
+ {
+ GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR,
+ "paivana",
+ "HTTP_PORT");
+ return GNUNET_SYSERR;
+ }
+ *port = (uint16_t) port_ull;
+ return GNUNET_OK;
+ }
+
+ /* serving via unix */
+
+ if (GNUNET_OK !=
+ GNUNET_CONFIGURATION_get_value_filename (ccfg,
+ "paivana",
+ "SERVE_UNIXPATH",
+ path))
+ {
+ GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR,
+ "paivana",
+ "SERVE_UNIXPATH");
+ return GNUNET_SYSERR;
+ }
+
+ if (GNUNET_OK !=
+ GNUNET_CONFIGURATION_get_value_string (ccfg,
+ "paivana",
+ "SERVE_UNIXMODE",
+ &modestring))
+ {
+ GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR,
+ "paivana",
+ "SERVE_UNIXMODE");
+ return GNUNET_SYSERR;
+ }
+
+ errno = 0;
+ *mode = (mode_t) strtoul (modestring, NULL, 8);
+
+ if (0 != errno)
+ {
+ GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
+ "paivana",
+ "SERVE_UNIXMODE",
+ "must be octal number");
+ GNUNET_free (modestring);
+ return GNUNET_SYSERR;
+ }
+ GNUNET_free (modestring);
+ return GNUNET_OK;
+}
+
+
+/**
+ * Main function that will be run. Main tasks are (1) init. the
+ * curl infrastructure (curl_global_init() / curl_multi_init()),
+ * then fetch the HTTP port where its Web service should listen at,
+ * and finally start MHD on that port.
+ *
+ * @param cls closure
+ * @param c configuration
+ * @param service the initialized service
+*/
+static void
+run (void *cls,
+ const struct GNUNET_CONFIGURATION_Handle *c,
+ struct GNUNET_SERVICE_Handle *service)
+{
+ uint16_t port = 0;
+ int fh = -1;
+ char *serve_unixpath = NULL;
+ mode_t serve_unixmode = 0;
+
+ (void) cls;
+ (void) service;
+ cfg = c;
+
+ if (0 != curl_global_init (CURL_GLOBAL_WIN32))
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+ "cURL global init failed!\n");
+ GNUNET_SCHEDULER_shutdown ();
+ return;
+ }
+ if (NULL == (curl_multi = curl_multi_init ()))
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+ "Failed to create cURL multi handle!\n");
+ return;
+ }
+
+ /* No need to check return value. If given, we take,
+ * otherwise it stays zero. */
+ if (GNUNET_OK !=
+ GNUNET_CONFIGURATION_get_value_string
+ (c,
+ "paivana",
+ "DESTINATION_BASE_URL",
+ &target_server_base_url))
+ {
+ GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR,
+ "paivana",
+ "DESTINATION_BASE_URL");
+ GNUNET_SCHEDULER_shutdown ();
+ return;
+ }
+
+ if (GNUNET_SYSERR ==
+ parse_serving_mean (c,
+ &port,
+ &serve_unixpath,
+ &serve_unixmode))
+ {
+ GNUNET_break (0);
+ GNUNET_SCHEDULER_shutdown ();
+ return;
+ }
+
+ if (NULL != serve_unixpath)
+ {
+ /* Connect the 'fh' socket. */
+ fh = open_unix_path (serve_unixpath,
+ serve_unixmode);
+
+ GNUNET_assert (-1 != fh);
+ }
+
+ /* start MHD daemon for HTTP */
+ mhd_daemon = MHD_start_daemon
+ (MHD_USE_DEBUG | MHD_ALLOW_SUSPEND_RESUME | MHD_USE_DUAL_STACK,
+ (-1 == fh) ? (uint16_t) port : 0,
+ NULL, NULL,
+ &create_response, NULL,
+ MHD_OPTION_CONNECTION_TIMEOUT, (unsigned int) 16,
+ MHD_OPTION_NOTIFY_COMPLETED, &mhd_completed_cb, NULL,
+ MHD_OPTION_URI_LOG_CALLBACK, &mhd_log_callback, NULL,
+ MHD_OPTION_LISTEN_SOCKET, fh,
+ MHD_OPTION_END);
+
+ if (NULL == mhd_daemon)
+ {
+ GNUNET_break (0);
+ GNUNET_SCHEDULER_shutdown ();
+ return;
+ }
+ GNUNET_SCHEDULER_add_shutdown (&do_shutdown,
+ NULL);
+ run_mhd_now ();
+}
+
+
+/**
+ * Main function.
+ */
+int
+main (int argc,
+ char *const *argv)
+{
+ return GNUNET_PROGRAM_run_ (PAIVANA_project_data (),
+ argc,
+ argv,
+ "paivana-httpd",
+ &run,
+ NULL);
+}
+
+
+/* end of paivana-httpd.c */
