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authorBenjamin Barenblat <bbaren@mit.edu>2015-06-23 15:42:22 -0400
committerBenjamin Barenblat <bbaren@mit.edu>2015-06-23 15:42:22 -0400
commit67aa9d138c9f8b966015d480fc77351c6fd77b68 (patch)
tree5b1b9bab3c6fcc2328941a56245f9da69dacf4a2
Initial commitv1.0.0
-rw-r--r--.gitignore46
-rw-r--r--LICENSE202
-rw-r--r--Makefile.am55
-rw-r--r--configure.ac46
-rw-r--r--m4/ax_cxx_compile_stdcxx_11.m4142
-rw-r--r--src/lib.urp5
-rw-r--r--src/random.cc91
-rw-r--r--src/random.h32
-rw-r--r--src/random.urs21
9 files changed, 640 insertions, 0 deletions
diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..ac66a6c
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,46 @@
+# -*- conf -*-
+
+# Editor backup files
+*~
+\#*
+.\#*
+
+# aclocal
+aclocal.m4
+autom4te.cache/
+
+# libtoolize
+ltmain.sh
+m4/libtool.m4
+m4/ltoptions.m4
+m4/ltsugar.m4
+m4/ltversion.m4
+m4/lt~obsolete.m4
+
+# autoconf
+configure
+
+# automake
+Makefile.in
+compile
+config.guess
+config.sub
+depcomp
+install-sh
+missing
+
+# configure
+.deps/
+Makefile
+config.log
+config.status
+config.urp
+libtool
+
+# make
+.dirstamp
+*.la
+*.lo
+*.o
+
+.libs/
diff --git a/LICENSE b/LICENSE
new file mode 100644
index 0000000..d645695
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,202 @@
+
+ Apache License
+ Version 2.0, January 2004
+ http://www.apache.org/licenses/
+
+ TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+ 1. Definitions.
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+ "License" shall mean the terms and conditions for use, reproduction,
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+ "Legal Entity" shall mean the union of the acting entity and all
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+ "You" (or "Your") shall mean an individual or Legal Entity
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+ 5. Submission of Contributions. Unless You explicitly state otherwise,
+ any Contribution intentionally submitted for inclusion in the Work
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+ 6. Trademarks. This License does not grant permission to use the trade
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+ 7. Disclaimer of Warranty. Unless required by applicable law or
+ agreed to in writing, Licensor provides the Work (and each
+ Contributor provides its Contributions) on an "AS IS" BASIS,
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+ 8. Limitation of Liability. In no event and under no legal theory,
+ whether in tort (including negligence), contract, or otherwise,
+ unless required by applicable law (such as deliberate and grossly
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+ on Your own behalf and on Your sole responsibility, not on behalf
+ of any other Contributor, and only if You agree to indemnify,
+ defend, and hold each Contributor harmless for any liability
+ incurred by, or claims asserted against, such Contributor by reason
+ of your accepting any such warranty or additional liability.
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+ To apply the Apache License to your work, attach the following
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+ Licensed under the Apache License, Version 2.0 (the "License");
+ you may not use this file except in compliance with the License.
+ You may obtain a copy of the License at
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+ http://www.apache.org/licenses/LICENSE-2.0
+
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
diff --git a/Makefile.am b/Makefile.am
new file mode 100644
index 0000000..26bb36b
--- /dev/null
+++ b/Makefile.am
@@ -0,0 +1,55 @@
+# Copyright 2015 the Massachusetts Institute of Technology
+#
+# Licensed under the Apache License, Version 2.0 (the "License"); you may not
+# use this file except in compliance with the License. You may obtain a copy of
+# the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations under
+# the License.
+
+ACLOCAL_AMFLAGS = -I m4
+
+CPPFLAGS = \
+ -Wall \
+ -D_FORTIFY_SOURCE=2 \
+ @OpenSSL_CFLAGS@
+
+CXXFLAGS = \
+ -std=c++11 \
+ -ftrapv \
+ -fstack-protector-strong --param=ssp-buffer-size=4 \
+ -fPIE \
+ -O2 \
+ @OpenSSL_CFLAGS@
+
+CXXFLAGS += \
+ -Weverything \
+ -Wno-c++98-compat
+
+LDFLAGS = \
+ -Wl,-Bsymbolic-functions \
+ -Wl,-z,relro \
+ -pie
+
+lib_LTLIBRARIES = liburweb_crypto_random_openssl.la
+
+liburweb_crypto_random_openssl_la_SOURCES = src/random.cc
+liburweb_crypto_random_openssl_la_DATA = \
+ src/lib.urp \
+ src/random.h \
+ src/random.urs
+
+liburweb_crypto_random_openssl_la_LIBADD = @OpenSSL_LIBS@ -lurweb
+liburweb_crypto_random_openssl_la_LDFLAGS = \
+ -export-symbols-regex '^uw_Random_'
+
+liburweb_crypto_random_openssl_ladir = $(datadir)/urweb/ur/crypto-random-openssl
+
+EXTRA_DIST = \
+ LICENSE \
+ $(liburweb_crypto_random_openssl_la_DATA)
diff --git a/configure.ac b/configure.ac
new file mode 100644
index 0000000..38a9f52
--- /dev/null
+++ b/configure.ac
@@ -0,0 +1,46 @@
+# Copyright 2015 the Massachusetts Institute of Technology
+#
+# Licensed under the Apache License, Version 2.0 (the "License"); you may not
+# use this file except in compliance with the License. You may obtain a copy of
+# the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations under
+# the License.
+
+AC_INIT([urweb-crypto-random-openssl], [1.0.0], [bbaren@mit.edu])
+AM_INIT_AUTOMAKE([no-dist-gzip dist-xz foreign subdir-objects])
+LT_INIT
+
+AC_CONFIG_MACRO_DIR([m4])
+
+AC_PROG_CXX([clang++])
+AX_CXX_COMPILE_STDCXX_11([noext], [mandatory])
+
+AC_CHECK_HEADERS([openssl/rand.h],
+ [],
+ [AC_MSG_FAILURE([OpenSSL headers are required])])
+PKG_CHECK_MODULES([OpenSSL], [openssl])
+
+AC_CHECK_HEADERS([urweb/urweb_cpp.h],
+ [],
+ [AC_MSG_FAILURE([Ur/Web headers are required])])
+save_LIBS=$LIBS
+LIBS="$LIBS -lurweb"
+AC_LINK_IFELSE([AC_LANG_CALL(
+ [int uw_init_client_data;
+ int uw_copy_client_data;
+ int uw_global_custom;
+ int uw_do_expunge;
+ int uw_post_expunge;
+ int uw_free_client_data;],
+ [uw_error])],
+ [],
+ [AC_MSG_FAILURE([could not link with -lurweb])])
+LIBS=$save_LIBS
+
+AC_OUTPUT([Makefile])
diff --git a/m4/ax_cxx_compile_stdcxx_11.m4 b/m4/ax_cxx_compile_stdcxx_11.m4
new file mode 100644
index 0000000..163a4c6
--- /dev/null
+++ b/m4/ax_cxx_compile_stdcxx_11.m4
@@ -0,0 +1,142 @@
+# ============================================================================
+# http://www.gnu.org/software/autoconf-archive/ax_cxx_compile_stdcxx_11.html
+# ============================================================================
+#
+# SYNOPSIS
+#
+# AX_CXX_COMPILE_STDCXX_11([ext|noext],[mandatory|optional])
+#
+# DESCRIPTION
+#
+# Check for baseline language coverage in the compiler for the C++11
+# standard; if necessary, add switches to CXXFLAGS to enable support.
+#
+# The first argument, if specified, indicates whether you insist on an
+# extended mode (e.g. -std=gnu++11) or a strict conformance mode (e.g.
+# -std=c++11). If neither is specified, you get whatever works, with
+# preference for an extended mode.
+#
+# The second argument, if specified 'mandatory' or if left unspecified,
+# indicates that baseline C++11 support is required and that the macro
+# should error out if no mode with that support is found. If specified
+# 'optional', then configuration proceeds regardless, after defining
+# HAVE_CXX11 if and only if a supporting mode is found.
+#
+# LICENSE
+#
+# Copyright (c) 2008 Benjamin Kosnik <bkoz@redhat.com>
+# Copyright (c) 2012 Zack Weinberg <zackw@panix.com>
+# Copyright (c) 2013 Roy Stogner <roystgnr@ices.utexas.edu>
+# Copyright (c) 2014 Alexey Sokolov <sokolov@google.com>
+#
+# Copying and distribution of this file, with or without modification, are
+# permitted in any medium without royalty provided the copyright notice
+# and this notice are preserved. This file is offered as-is, without any
+# warranty.
+
+#serial 4
+
+m4_define([_AX_CXX_COMPILE_STDCXX_11_testbody], [[
+ template <typename T>
+ struct check
+ {
+ static_assert(sizeof(int) <= sizeof(T), "not big enough");
+ };
+
+ struct Base {
+ virtual void f() {}
+ };
+ struct Child : public Base {
+ virtual void f() override {}
+ };
+
+ typedef check<check<bool>> right_angle_brackets;
+
+ int a;
+ decltype(a) b;
+
+ typedef check<int> check_type;
+ check_type c;
+ check_type&& cr = static_cast<check_type&&>(c);
+
+ auto d = a;
+ auto l = [](){};
+]])
+
+AC_DEFUN([AX_CXX_COMPILE_STDCXX_11], [dnl
+ m4_if([$1], [], [],
+ [$1], [ext], [],
+ [$1], [noext], [],
+ [m4_fatal([invalid argument `$1' to AX_CXX_COMPILE_STDCXX_11])])dnl
+ m4_if([$2], [], [ax_cxx_compile_cxx11_required=true],
+ [$2], [mandatory], [ax_cxx_compile_cxx11_required=true],
+ [$2], [optional], [ax_cxx_compile_cxx11_required=false],
+ [m4_fatal([invalid second argument `$2' to AX_CXX_COMPILE_STDCXX_11])])
+ AC_LANG_PUSH([C++])dnl
+ ac_success=no
+ AC_CACHE_CHECK(whether $CXX supports C++11 features by default,
+ ax_cv_cxx_compile_cxx11,
+ [AC_COMPILE_IFELSE([AC_LANG_SOURCE([_AX_CXX_COMPILE_STDCXX_11_testbody])],
+ [ax_cv_cxx_compile_cxx11=yes],
+ [ax_cv_cxx_compile_cxx11=no])])
+ if test x$ax_cv_cxx_compile_cxx11 = xyes; then
+ ac_success=yes
+ fi
+
+ m4_if([$1], [noext], [], [dnl
+ if test x$ac_success = xno; then
+ for switch in -std=gnu++11 -std=gnu++0x; do
+ cachevar=AS_TR_SH([ax_cv_cxx_compile_cxx11_$switch])
+ AC_CACHE_CHECK(whether $CXX supports C++11 features with $switch,
+ $cachevar,
+ [ac_save_CXXFLAGS="$CXXFLAGS"
+ CXXFLAGS="$CXXFLAGS $switch"
+ AC_COMPILE_IFELSE([AC_LANG_SOURCE([_AX_CXX_COMPILE_STDCXX_11_testbody])],
+ [eval $cachevar=yes],
+ [eval $cachevar=no])
+ CXXFLAGS="$ac_save_CXXFLAGS"])
+ if eval test x\$$cachevar = xyes; then
+ CXXFLAGS="$CXXFLAGS $switch"
+ ac_success=yes
+ break
+ fi
+ done
+ fi])
+
+ m4_if([$1], [ext], [], [dnl
+ if test x$ac_success = xno; then
+ for switch in -std=c++11 -std=c++0x; do
+ cachevar=AS_TR_SH([ax_cv_cxx_compile_cxx11_$switch])
+ AC_CACHE_CHECK(whether $CXX supports C++11 features with $switch,
+ $cachevar,
+ [ac_save_CXXFLAGS="$CXXFLAGS"
+ CXXFLAGS="$CXXFLAGS $switch"
+ AC_COMPILE_IFELSE([AC_LANG_SOURCE([_AX_CXX_COMPILE_STDCXX_11_testbody])],
+ [eval $cachevar=yes],
+ [eval $cachevar=no])
+ CXXFLAGS="$ac_save_CXXFLAGS"])
+ if eval test x\$$cachevar = xyes; then
+ CXXFLAGS="$CXXFLAGS $switch"
+ ac_success=yes
+ break
+ fi
+ done
+ fi])
+ AC_LANG_POP([C++])
+ if test x$ax_cxx_compile_cxx11_required = xtrue; then
+ if test x$ac_success = xno; then
+ AC_MSG_ERROR([*** A compiler with support for C++11 language features is required.])
+ fi
+ else
+ if test x$ac_success = xno; then
+ HAVE_CXX11=0
+ AC_MSG_NOTICE([No compiler with C++11 support was found])
+ else
+ HAVE_CXX11=1
+ AC_DEFINE(HAVE_CXX11,1,
+ [define if the compiler supports basic C++11 syntax])
+ fi
+
+ AC_SUBST(HAVE_CXX11)
+ fi
+])
diff --git a/src/lib.urp b/src/lib.urp
new file mode 100644
index 0000000..62b02ba
--- /dev/null
+++ b/src/lib.urp
@@ -0,0 +1,5 @@
+ffi random
+benignEffectful Random.bytes
+benignEffectful Random.int
+include random.h
+link -lurweb_crypto_random_openssl -lcrypto
diff --git a/src/random.cc b/src/random.cc
new file mode 100644
index 0000000..12deaf0
--- /dev/null
+++ b/src/random.cc
@@ -0,0 +1,91 @@
+// Copyright (C) 2015 the Massachusetts Institute of Technology
+//
+// Licensed under the Apache License, Version 2.0 (the "License"); you may not
+// use this file except in compliance with the License. You may obtain a copy
+// of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+// WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+// License for the specific language governing permissions and limitations under
+// the License.
+
+#include "random.h"
+
+#include <cstddef>
+#include <limits>
+
+#include <openssl/rand.h>
+extern "C" {
+#include <urweb/urweb_cpp.h>
+}
+
+static_assert(sizeof(char) == 1, "char is not a single byte");
+static_assert(sizeof(unsigned char) == 1, "unsigned char is not a single byte");
+
+namespace {
+
+// Asserts a condition without crashing or releasing information about where the
+// error occurred. This function is essential for web programming, where an
+// attacker should not be able to bring down the app by causing an assertion
+// failure.
+void Assert(uw_context* const context, const bool condition,
+ const failure_kind action, const char* const message) {
+ if (!condition) {
+ uw_error(context, action, message);
+ }
+}
+
+void Assert(uw_context* const context,
+ const bool condition, const char* const message) {
+ Assert(context, condition, FATAL, message);
+}
+
+char* RandomBytes(struct uw_context* const context, const int n_bytes) {
+ Assert(context, 0 <= n_bytes,
+ "cannot produce a negative number of random bytes");
+ // Allocate for the result. Ensure that no precision gets lost when casting
+ // from int to std::size_t.
+ static_assert(std::numeric_limits<int>::max()
+ <= std::numeric_limits<std::size_t>::max(),
+ "int is larger than expected");
+ unsigned char* const result_bytes =
+ static_cast<unsigned char*>(uw_malloc(context,
+ static_cast<std::size_t>(n_bytes)));
+ // Fill it with random data.
+ Assert(context, RAND_bytes(result_bytes, n_bytes) == 1, BOUNDED_RETRY,
+ "cannot generate random data");
+ return reinterpret_cast<char*>(result_bytes);
+}
+
+} // namespace
+
+uw_Basis_int uw_Random_int(struct uw_context* const context) {
+ return *reinterpret_cast<uw_Basis_int*>(RandomBytes(context,
+ sizeof(uw_Basis_int)));
+}
+
+uw_Basis_blob uw_Random_bytes(struct uw_context* const context,
+ const uw_Basis_int ur_n_bytes) {
+ // We need to use ur_n_bytes as a number of different types in this function.
+ // The smallest one, however, is almost certainly int. Ensure that that's the
+ // case.
+ static_assert(std::numeric_limits<int>::max()
+ <= std::numeric_limits<std::size_t>::max(),
+ "int is larger than expected");
+ static_assert(std::numeric_limits<int>::max()
+ <= std::numeric_limits<uw_Basis_int>::max(),
+ "int is larger than expected");
+ // Ensure that we don't lose precision when converting ur_n_bytes to int, and
+ // do so.
+ Assert(context, 0 <= ur_n_bytes,
+ "cannot produce a negative number of random bytes");
+ Assert(context, ur_n_bytes < std::numeric_limits<int>::max(),
+ "requested number of bytes is larger than supported");
+ const int n_bytes = static_cast<int>(ur_n_bytes);
+ // Generate random data.
+ return uw_Basis_blob{static_cast<std::size_t>(n_bytes),
+ RandomBytes(context, n_bytes)};
+}
diff --git a/src/random.h b/src/random.h
new file mode 100644
index 0000000..4d05ac3
--- /dev/null
+++ b/src/random.h
@@ -0,0 +1,32 @@
+// Copyright (C) 2015 the Massachusetts Institute of Technology
+//
+// Licensed under the Apache License, Version 2.0 (the "License"); you may not
+// use this file except in compliance with the License. You may obtain a copy
+// of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+// WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+// License for the specific language governing permissions and limitations under
+// the License.
+
+#ifndef URWEB_CRYPTO_RANDOM_OPENSSL_RANDOM_H
+#define URWEB_CRYPTO_RANDOM_OPENSSL_RANDOM_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <urweb/urweb_cpp.h>
+
+uw_Basis_int uw_Random_int(struct uw_context*);
+
+uw_Basis_blob uw_Random_bytes(struct uw_context*, const uw_Basis_int);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif // URWEB_CRYPTO_RANDOM_OPENSSL_RANDOM_H
diff --git a/src/random.urs b/src/random.urs
new file mode 100644
index 0000000..284336b
--- /dev/null
+++ b/src/random.urs
@@ -0,0 +1,21 @@
+(* Copyright 2015 the Massachusetts Institute of Technology
+
+Licensed under the Apache License, Version 2.0 (the "License"); you may not use
+this file except in compliance with the License. You may obtain a copy of the
+License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software distributed
+under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
+CONDITIONS OF ANY KIND, either express or implied. See the License for the
+specific language governing permissions and limitations under the License. *)
+
+(* Generates a random int, chosen uniformly using a cryptographically secure
+entropy pool. *)
+val int : transaction int
+
+(* Returns a blob containing the specified number of cryptographically secure
+pseudorandom bytes. You must specify a nonnegative number equal or less than
+INT_MAX as defined by your platform. *)
+val bytes : int -> transaction blob