nettle: import from packages, update to 3.0

Signed-off-by: Steven Barth <steven@midlink.org>

SVN-Revision: 41248
This commit is contained in:
Steven Barth 2014-06-18 10:04:43 +00:00
parent 335529e207
commit a0e19ec2f9
6 changed files with 1843 additions and 0 deletions

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@ -0,0 +1,9 @@
# nettle avanced configuration
menu "Configuration"
depends on PACKAGE_libnettle
config LIBNETTLE_MINI
bool "use mini-gmp instead of gmp; the library will be much smaller at a 10x performance penalty. Note that this option may have side effects to programs that link to both nettle and gmp."
endmenu

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@ -0,0 +1,85 @@
#
# Copyright (C) 2014 OpenWrt.org
#
# This is free software, licensed under the GNU General Public License v2.
# See /LICENSE for more information.
#
include $(TOPDIR)/rules.mk
PKG_NAME:=nettle
PKG_VERSION:=3.0
PKG_RELEASE:=1
PKG_SOURCE:=$(PKG_NAME)-$(PKG_VERSION).tar.gz
PKG_SOURCE_URL:=@GNU/nettle
PKG_MD5SUM:=f64b1bf1e774b7ae6e507318e340250e
PKG_MAINTAINER:=Nikos Mavrogiannopoulos <nmav@gnutls.org>
PKG_LICENSE:=LGPLv2
PKG_LICENSE_FILES:=COPYING
PKG_FIXUP:=autoreconf
PKG_BUILD_PARALLEL:=0
include $(INCLUDE_DIR)/package.mk
define Package/libnettle
SECTION:=libs
CATEGORY:=Libraries
TITLE:=GNU crypto library
URL:=http://www.lysator.liu.se/~nisse/nettle/
DEPENDS+= +!LIBNETTLE_MINI:libgmp
endef
define Package/libnettle/config
source "$(SOURCE)/Config.in"
endef
TARGET_CFLAGS += $(FPIC)
CONFIGURE_ARGS += \
--enable-shared \
--disable-openssl \
--disable-documentation \
--enable-static
ifeq ($(CONFIG_LIBNETTLE_MINI),y)
CONFIGURE_ARGS += --enable-mini-gmp
endif
ifeq ($(CONFIG_CPU_SUBTYPE),neon)
CONFIGURE_ARGS += \
--enable-arm-neon
endif
define Build/Compile
$(call Build/Compile/Default, \
DESTDIR="$(PKG_INSTALL_DIR)" \
CC="$(TARGET_CC)" \
libnettle.so libhogweed.so
+$(MAKE) -i $(PKG_JOBS) -C $(PKG_BUILD_DIR) \
DESTDIR="$(PKG_INSTALL_DIR)" \
install)
endef
define Build/InstallDev
$(INSTALL_DIR) $(1)/usr/include/nettle
$(CP) $(PKG_INSTALL_DIR)/usr/include/nettle/*.h $(1)/usr/include/nettle/
$(INSTALL_DIR) $(1)/usr/lib
$(CP) $(PKG_INSTALL_DIR)/usr/lib/libnettle.{a,so*} $(1)/usr/lib/
$(CP) $(PKG_INSTALL_DIR)/usr/lib/libhogweed.{a,so*} $(1)/usr/lib/
$(INSTALL_DIR) $(1)/usr/lib/pkgconfig
$(CP) \
$(PKG_INSTALL_DIR)/usr/lib/pkgconfig/nettle.pc \
$(PKG_INSTALL_DIR)/usr/lib/pkgconfig/hogweed.pc \
$(1)/usr/lib/pkgconfig/
endef
define Package/libnettle/install
$(INSTALL_DIR) $(1)/usr/lib
$(CP) $(PKG_INSTALL_DIR)/usr/lib/libnettle.so.* $(1)/usr/lib/
$(CP) $(PKG_INSTALL_DIR)/usr/lib/libhogweed.so.* $(1)/usr/lib/
endef
$(eval $(call BuildPackage,libnettle))

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@ -0,0 +1,403 @@
From 8d5360e3e5eea3c9dbfd44f9b981f18a41605e45 Mon Sep 17 00:00:00 2001
From: Nikos Mavrogiannopoulos <nmav@gnutls.org>
Date: Sun, 9 Mar 2014 11:30:25 +0100
Subject: [PATCH 2/5] Added option to use mini-gmp in hogweed.
---
Makefile.in | 8 +++--
bignum.h | 6 +++-
configure.ac | 76 +++++++++++++++++++++++++++++++++++-------------
dsa.h | 2 +-
ecc-internal.h | 2 +-
ecc.h | 2 +-
eccdata.c | 12 +++++++-
examples/Makefile.in | 2 +-
examples/ecc-benchmark.c | 2 ++
gmp-glue.c | 1 +
gmp-glue.h | 2 +-
hogweed.pc.in | 2 +-
mini-gmp.c | 2 +-
mini-gmp.h | 9 ++++++
pkcs1.h | 2 +-
rsa.h | 2 +-
testsuite/Makefile.in | 4 +--
testsuite/testutils.h | 5 ++--
18 files changed, 102 insertions(+), 39 deletions(-)
--- a/Makefile.in
+++ b/Makefile.in
@@ -15,6 +15,10 @@ MKDIR_P = @MKDIR_P@
OPT_ASM_NETTLE_SOURCES = @OPT_ASM_NETTLE_SOURCES@
OPT_ASM_HOGWEED_SOURCES = @OPT_ASM_HOGWEED_SOURCES@
+OPT_HOGWEED_SOURCES = @OPT_HOGWEED_SOURCES@
+
+OPT_HOGWEED_HEADERS = @OPT_HOGWEED_HEADERS@
+
SUBDIRS = tools testsuite examples
include config.make
@@ -132,7 +136,7 @@ nettle_SOURCES = aes-decrypt-internal.c
write-be32.c write-le32.c write-le64.c \
yarrow256.c yarrow_key_event.c
-hogweed_SOURCES = sexp.c sexp-format.c \
+hogweed_SOURCES = $(OPT_HOGWEED_SOURCES) sexp.c sexp-format.c \
sexp-transport.c sexp-transport-format.c \
bignum.c bignum-random.c bignum-random-prime.c \
sexp2bignum.c \
@@ -183,7 +187,7 @@ HEADERS = aes.h arcfour.h arctwo.h asn1.
pgp.h pkcs1.h realloc.h ripemd160.h rsa.h \
salsa20.h sexp.h \
serpent.h sha.h sha1.h sha2.h sha3.h twofish.h \
- umac.h yarrow.h poly1305.h
+ umac.h yarrow.h poly1305.h $(OPT_HOGWEED_HEADERS)
INSTALL_HEADERS = $(HEADERS) nettle-stdint.h
--- a/bignum.h
+++ b/bignum.h
@@ -36,7 +36,11 @@
#include "nettle-meta.h"
-#include <gmp.h>
+#ifdef USE_MINI_GMP
+# include "mini-gmp.h"
+#else
+# include <gmp.h>
+#endif
#include "nettle-types.h"
#ifdef __cplusplus
--- a/configure.ac
+++ b/configure.ac
@@ -72,6 +72,16 @@ AC_ARG_ENABLE(arm-neon,
AC_HELP_STRING([--enable-arm-neon], [Enable ARM Neon assembly. (default=auto)]),,
[enable_arm_neon=auto])
+AC_ARG_ENABLE(mini-gmp,
+ AC_HELP_STRING([--enable-mini-gmp], [Disable gmp support and enable mini-gmp. (default=disabled)]),,
+ [enable_mini_gmp=no])
+
+if test "x$enable_mini_gmp" = xyes ; then
+GMP_LIBS=""
+else
+GMP_LIBS="-lgmp"
+fi
+
LSH_RPATH_INIT([`echo $with_lib_path | sed 's/:/ /g'` \
`echo $exec_prefix | sed "s@^NONE@$prefix/lib@g" | sed "s@^NONE@$ac_default_prefix/lib@g"` \
/usr/local/lib /sw/local/lib /sw/lib \
@@ -441,7 +451,7 @@ case "$host_os" in
LIBHOGWEED_SONAME='libhogweed.$(LIBHOGWEED_MAJOR).dylib'
LIBHOGWEED_FILE='libhogweed.$(LIBHOGWEED_MAJOR).$(LIBHOGWEED_MINOR).dylib'
LIBHOGWEED_LINK='$(CC) $(CFLAGS) -dynamiclib -L. $(LDFLAGS) -install_name ${libdir}/$(LIBHOGWEED_SONAME) -compatibility_version $(LIBHOGWEED_MAJOR) -current_version $(LIBHOGWEED_MAJOR).$(LIBHOGWEED_MINOR)'
- LIBHOGWEED_LIBS='-lnettle -lgmp'
+ LIBHOGWEED_LIBS='-lnettle $(GMP_LIBS)'
;;
solaris*)
# Sun's ld uses -h to set the soname, and this option is passed
@@ -457,7 +467,7 @@ case "$host_os" in
LIBHOGWEED_SONAME='$(LIBHOGWEED_FORLINK).$(LIBHOGWEED_MAJOR)'
LIBHOGWEED_FILE='$(LIBHOGWEED_SONAME).$(LIBHOGWEED_MINOR)'
LIBHOGWEED_LINK='$(CC) $(CFLAGS) $(LDFLAGS) -G -h $(LIBHOGWEED_SONAME)'
- LIBHOGWEED_LIBS='libnettle.so -lgmp'
+ LIBHOGWEED_LIBS='libnettle.so $(GMP_LIBS)'
;;
*)
LIBNETTLE_FORLINK=libnettle.so
@@ -474,7 +484,7 @@ case "$host_os" in
# (does not work in general, e.g., with static linking all of
# -lhogweed -lgmp -lnettle are still required). Also makes dlopen
# of libhogweed.so work, without having to use RTLD_GLOBAL.
- LIBHOGWEED_LIBS='libnettle.so -lgmp'
+ LIBHOGWEED_LIBS='libnettle.so $(GMP_LIBS)'
;;
esac
@@ -692,7 +702,18 @@ if test "x$nettle_cv_fcntl_locking" = "x
fi
# Checks for libraries
+TESTSUITE_LIBS=""
+
+OPT_HOGWEED_SOURCES=""
+OPT_HOGWEED_HEADERS=""
if test "x$enable_public_key" = "xyes" ; then
+if test "x$enable_mini_gmp" = xyes ; then
+ OPT_HOGWEED_SOURCES="$OPT_HOGWEED_SOURCES mini-gmp.c"
+ OPT_HOGWEED_HEADERS="$OPT_HOGWEED_HEADERS mini-gmp.h"
+ AC_DEFINE([USE_MINI_GMP], 1, [Use mini-gmp instead of gmp])
+ IF_NOT_MINI_GMP='#'
+ GMP_NUMB_BITS="0"
+else
AC_CHECK_LIB(gmp, __gmpz_getlimbn,,
[AC_MSG_WARN(
[GNU MP not found, or not 3.1 or up, see http://gmplib.org/.
@@ -701,9 +722,7 @@ if test "x$enable_public_key" = "xyes" ;
# Add -R flags needed to run programs linked with gmp
LSH_RPATH_FIX
-fi
-if test "x$enable_public_key" = "xyes" ; then
# Check for gmp limb size
nettle_cv_gmp_numb_bits=0
if test "$enable_public_key" = yes; then
@@ -714,12 +733,23 @@ if test "x$enable_public_key" = "xyes" ;
AC_MSG_RESULT([$nettle_cv_gmp_numb_bits bits])
fi
+
GMP_NUMB_BITS="$nettle_cv_gmp_numb_bits"
AC_SUBST([GMP_NUMB_BITS])
AH_TEMPLATE([HAVE_MPZ_POWM_SEC], [Define if mpz_powm_sec is available (appeared in GMP-5)])
AC_CHECK_FUNC(__gmpz_powm_sec, [AC_DEFINE(HAVE_MPZ_POWM_SEC)])
+ IF_NOT_MINI_GMP=''
+ TESTSUITE_LIBS="-lgmp"
+fi
+ AC_SUBST([GMP_LIBS])
+dnl The testsuite requires gmp
+AC_SUBST([TESTSUITE_LIBS])
+AC_SUBST([GMP_NUMB_BITS])
+AC_SUBST([OPT_HOGWEED_SOURCES])
+AC_SUBST([OPT_HOGWEED_HEADERS])
+
fi
AH_TEMPLATE([WITH_HOGWEED], [Defined if public key features are enabled])
@@ -765,6 +795,7 @@ else
IF_DOCUMENTATION='#'
fi
+AC_SUBST(IF_NOT_MINI_GMP)
AC_SUBST(IF_HOGWEED)
AC_SUBST(IF_STATIC)
AC_SUBST(IF_SHARED)
--- a/dsa.h
+++ b/dsa.h
@@ -34,7 +34,7 @@
#ifndef NETTLE_DSA_H_INCLUDED
#define NETTLE_DSA_H_INCLUDED
-#include <gmp.h>
+#include "bignum.h"
#include "nettle-types.h"
--- a/ecc-internal.h
+++ b/ecc-internal.h
@@ -34,7 +34,7 @@
#ifndef NETTLE_ECC_INTERNAL_H_INCLUDED
#define NETTLE_ECC_INTERNAL_H_INCLUDED
-#include <gmp.h>
+#include "bignum.h"
#include "nettle-types.h"
#include "ecc-curve.h"
--- a/ecc.h
+++ b/ecc.h
@@ -34,7 +34,7 @@
#ifndef NETTLE_ECC_H_INCLUDED
#define NETTLE_ECC_H_INCLUDED
-#include <gmp.h>
+#include "bignum.h"
#include "nettle-types.h"
--- a/eccdata.c
+++ b/eccdata.c
@@ -33,11 +33,14 @@
/* Development of Nettle's ECC support was funded by the .SE Internet Fund. */
+#include "config.h"
+
#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
+#include "mini-gmp.h"
#include "mini-gmp.c"
/* Affine coordinates, for simplicity. Infinity point represented as x
@@ -904,6 +907,7 @@ int
main (int argc, char **argv)
{
struct ecc_curve ecc;
+ unsigned bits;
if (argc < 4)
{
@@ -911,6 +915,7 @@ main (int argc, char **argv)
return EXIT_FAILURE;
}
+ bits = atoi(argv[4]);
ecc_curve_init (&ecc, atoi(argv[1]));
ecc_pippenger_precompute (&ecc, atoi(argv[2]), atoi(argv[3]));
@@ -921,7 +926,12 @@ main (int argc, char **argv)
ecc_curve_check (&ecc);
if (argc > 4)
- output_curve (&ecc, atoi(argv[4]));
+ {
+ /* when using mini-gmp we cannot estimate it on configure */
+ if (bits == 0)
+ bits = GMP_NUMB_BITS;
+ output_curve (&ecc, bits);
+ }
return EXIT_SUCCESS;
}
--- a/examples/Makefile.in
+++ b/examples/Makefile.in
@@ -11,7 +11,7 @@ PRE_CPPFLAGS = -I.. -I$(top_srcdir)
PRE_LDFLAGS = -L..
OPENSSL_LIBFLAGS = @OPENSSL_LIBFLAGS@
-BENCH_LIBS = @BENCH_LIBS@ -lm
+BENCH_LIBS = @BENCH_LIBS@ $(TESTSUITE_LIBS) -lm
HOGWEED_TARGETS = rsa-keygen$(EXEEXT) rsa-sign$(EXEEXT) \
rsa-verify$(EXEEXT) rsa-encrypt$(EXEEXT) rsa-decrypt$(EXEEXT) \
--- a/examples/ecc-benchmark.c
+++ b/examples/ecc-benchmark.c
@@ -46,6 +46,8 @@
#include "timing.h"
+#undef USE_MINI_GMP
+#include <gmp.h>
#include "../ecc.h"
#include "../ecc-internal.h"
#include "../gmp-glue.h"
--- a/gmp-glue.c
+++ b/gmp-glue.c
@@ -271,3 +271,4 @@ gmp_free(void *p, size_t n)
free_func (p, (size_t) n);
}
+
--- a/gmp-glue.h
+++ b/gmp-glue.h
@@ -33,7 +33,7 @@
#ifndef NETTLE_GMP_GLUE_H_INCLUDED
#define NETTLE_GMP_GLUE_H_INCLUDED
-#include <gmp.h>
+#include "bignum.h"
#include "nettle-stdint.h"
--- a/hogweed.pc.in
+++ b/hogweed.pc.in
@@ -13,6 +13,6 @@ URL: http://www.lysator.liu.se/~nisse/ne
Version: @PACKAGE_VERSION@
Requires.private: nettle
Libs: -L${libdir} -lhogweed
-Libs.private: -lgmp
+Libs.private: @GMP_LIBS@
Cflags: -I${includedir}
--- a/mini-gmp.c
+++ b/mini-gmp.c
@@ -1388,7 +1388,7 @@ mpz_clear (mpz_t r)
gmp_free (r->_mp_d);
}
-static void *
+void *
mpz_realloc (mpz_t r, mp_size_t size)
{
size = GMP_MAX (size, 1);
--- a/mini-gmp.h
+++ b/mini-gmp.h
@@ -70,6 +70,11 @@ typedef struct
mp_limb_t *_mp_d; /* Pointer to the limbs. */
} __mpz_struct;
+typedef __mpz_struct MP_INT;
+
+#define GMP_NUMB_BITS (SIZEOF_LONG*8)
+#define GMP_NUMB_MASK (~0)
+
typedef __mpz_struct mpz_t[1];
typedef __mpz_struct *mpz_ptr;
@@ -119,6 +124,10 @@ void mpz_init (mpz_t);
void mpz_init2 (mpz_t, mp_bitcnt_t);
void mpz_clear (mpz_t);
+void *
+mpz_realloc (mpz_t r, mp_size_t size);
+#define _mpz_realloc mpz_realloc
+
#define mpz_odd_p(z) (((z)->_mp_size != 0) & (int) (z)->_mp_d[0])
#define mpz_even_p(z) (! mpz_odd_p (z))
--- a/pkcs1.h
+++ b/pkcs1.h
@@ -34,7 +34,7 @@
#ifndef NETTLE_PKCS1_H_INCLUDED
#define NETTLE_PKCS1_H_INCLUDED
-#include <gmp.h>
+#include "bignum.h"
#include "nettle-types.h"
#ifdef __cplusplus
--- a/rsa.h
+++ b/rsa.h
@@ -34,7 +34,7 @@
#ifndef NETTLE_RSA_H_INCLUDED
#define NETTLE_RSA_H_INCLUDED
-#include <gmp.h>
+#include "bignum.h"
#include "nettle-types.h"
#include "md5.h"
--- a/testsuite/Makefile.in
+++ b/testsuite/Makefile.in
@@ -50,7 +50,7 @@ TS_HOGWEED = $(TS_HOGWEED_SOURCES:.c=$(E
TS_C = $(TS_NETTLE) @IF_HOGWEED@ $(TS_HOGWEED)
TS_CXX = @IF_CXX@ $(CXX_SOURCES:.cxx=$(EXEEXT))
TARGETS = $(TS_C) $(TS_CXX)
-TS_SH = sexp-conv-test pkcs1-conv-test nettle-pbkdf2-test symbols-test
+TS_SH = sexp-conv-test pkcs1-conv-test nettle-pbkdf2-test symbols-test @IF_NOT_MINI_GMP@
TS_ALL = $(TARGETS) $(TS_SH)
EXTRA_SOURCES = sha1-huge-test.c
EXTRA_TARGETS = $(EXTRA_SOURCES:.c=$(EXEEXT))
@@ -78,7 +78,7 @@ all: $(EXTRA_TARGETS)
LIB_HOGWEED = @IF_HOGWEED@ -lhogweed
TEST_OBJS = testutils.$(OBJEXT) ../nettle-internal.$(OBJEXT) \
- $(LIB_HOGWEED) -lnettle $(LIBS)
+ $(LIB_HOGWEED) -lnettle $(LIBS) $(TESTSUITE_LIBS)
../nettle-internal.$(OBJEXT):
( cd .. && $(MAKE) nettle-internal.$(OBJEXT) )
--- a/testsuite/testutils.h
+++ b/testsuite/testutils.h
@@ -12,11 +12,10 @@
#include <stdio.h>
#include <string.h>
-#if HAVE_LIBGMP
-# include "bignum.h"
-#endif
#if WITH_HOGWEED
+# include <gmp.h>
+# undef USE_MINI_GMP
# include "rsa.h"
# include "dsa-compat.h"
# include "ecc-curve.h"

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@ -0,0 +1,84 @@
From 7508bb15de94b38402152757f75ff3e2094fdd86 Mon Sep 17 00:00:00 2001
From: Nikos Mavrogiannopoulos <nmav@gnutls.org>
Date: Sun, 9 Mar 2014 13:27:03 +0100
Subject: [PATCH 4/5] Added-auto-generated-nettle-config.h
---
Makefile.in | 4 ++--
bignum.h | 1 +
configure.ac | 1 +
examples/ecc-benchmark.c | 1 +
nettle-config.h.in | 6 ++++++
testsuite/testutils.h | 1 +
7 files changed, 13 insertions(+), 2 deletions(-)
create mode 100644 nettle-config.h.in
--- a/Makefile.in
+++ b/Makefile.in
@@ -178,7 +178,7 @@ HEADERS = aes.h arcfour.h arctwo.h asn1.
ecc-curve.h ecc.h ecdsa.h \
gcm.h gosthash94.h hmac.h \
knuth-lfib.h \
- macros.h \
+ macros.h nettle-config.h \
md2.h md4.h \
md5.h md5-compat.h \
memxor.h \
@@ -203,7 +203,7 @@ DISTFILES = $(SOURCES) $(HEADERS) getopt
config.h.in config.m4.in config.make.in Makefile.in \
README AUTHORS COPYING.LESSERv3 COPYINGv2 COPYINGv3 \
INSTALL NEWS TODO ChangeLog \
- nettle.pc.in hogweed.pc.in \
+ nettle.pc.in hogweed.pc.in nettle-config.h.in \
$(des_headers) descore.README \
aes-internal.h camellia-internal.h serpent-internal.h \
cast128_sboxes.h desinfo.h desCode.h \
--- a/bignum.h
+++ b/bignum.h
@@ -34,6 +34,7 @@
#ifndef NETTLE_BIGNUM_H_INCLUDED
#define NETTLE_BIGNUM_H_INCLUDED
+#include "nettle-config.h"
#include "nettle-meta.h"
#ifdef USE_MINI_GMP
--- a/configure.ac
+++ b/configure.ac
@@ -10,6 +10,7 @@ AC_CONFIG_AUX_DIR([.])
AC_CONFIG_MACRO_DIR([.])
AC_CONFIG_HEADER([config.h])
+AC_CONFIG_HEADER([nettle-config.h])
LIBNETTLE_MAJOR=5
LIBNETTLE_MINOR=0
--- a/examples/ecc-benchmark.c
+++ b/examples/ecc-benchmark.c
@@ -47,6 +47,7 @@
#include "timing.h"
#undef USE_MINI_GMP
+#define NETTLE_CONFIG_H_INCLUDED
#include <gmp.h>
#include "../ecc.h"
#include "../ecc-internal.h"
--- /dev/null
+++ b/nettle-config.h.in
@@ -0,0 +1,6 @@
+#ifndef NETTLE_CONFIG_H_INCLUDED
+#define NETTLE_CONFIG_H_INCLUDED
+
+#undef USE_MINI_GMP
+
+#endif
--- a/testsuite/testutils.h
+++ b/testsuite/testutils.h
@@ -15,6 +15,7 @@
#if WITH_HOGWEED
# include <gmp.h>
+# define NETTLE_CONFIG_H_INCLUDED
# undef USE_MINI_GMP
# include "rsa.h"
# include "dsa-compat.h"

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@ -0,0 +1,29 @@
From d71b3138cbdc3852c96a2639995f2d7f44b1c76c Mon Sep 17 00:00:00 2001
From: Nikos Mavrogiannopoulos <nmav@gnutls.org>
Date: Sat, 29 Mar 2014 09:12:41 +0100
Subject: [PATCH 5/5] allow der-iterator to be used with mini-gmp
---
der-iterator.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
--- a/der-iterator.c
+++ b/der-iterator.c
@@ -38,7 +38,7 @@
#include <assert.h>
#include <stdlib.h>
-#if HAVE_LIBGMP
+#if defined(HAVE_LIBGMP) || defined(USE_MINI_GMP)
#include "bignum.h"
#endif
@@ -254,7 +254,7 @@ asn1_der_get_uint32(struct asn1_der_iter
return 1;
}
-#if HAVE_LIBGMP
+#if defined(HAVE_LIBGMP) || defined(USE_MINI_GMP)
int
asn1_der_get_bignum(struct asn1_der_iterator *i,
mpz_t x, unsigned max_bits)