.libs/

autom4te.cache/

.deps/

src/libsecp256k1-config.h

src/libsecp256k1-config.h.in

src/ecmult_static_context.h

build-aux/config.guess

build-aux/config.sub

build-aux/depcomp

build-aux/install-sh

build-aux/ltmain.sh

build-aux/m4/libtool.m4

build-aux/m4/lt~obsolete.m4

build-aux/m4/ltoptions.m4

build-aux/m4/ltsugar.m4

build-aux/m4/ltversion.m4

build-aux/missing

build-aux/compile

build-aux/test-driver

src/stamp-h1

language: c

sudo: false

addons:

apt:

packages: libgmp-dev

compiler:

- clang

- gcc

cache:

directories:

- src/java/guava/

env:

global:

- FIELD=auto BIGNUM=auto SCALAR=auto ENDOMORPHISM=no STATICPRECOMPUTATION=yes ASM=no BUILD=check EXTRAFLAGS= HOST= ECDH=no RECOVERY=no EXPERIMENTAL=no JNI=no

- GUAVA_URL=https://search.maven.org/remotecontent?filepath=com/google/guava/guava/18.0/guava-18.0.jar GUAVA_JAR=src/java/guava/guava-18.0.jar

matrix:

- SCALAR=32bit RECOVERY=yes

- SCALAR=32bit FIELD=32bit ECDH=yes EXPERIMENTAL=yes

- SCALAR=64bit

- FIELD=64bit RECOVERY=yes

- FIELD=64bit ENDOMORPHISM=yes

- FIELD=64bit ENDOMORPHISM=yes ECDH=yes EXPERIMENTAL=yes

- FIELD=64bit ASM=x86_64

- FIELD=64bit ENDOMORPHISM=yes ASM=x86_64

- FIELD=32bit ENDOMORPHISM=yes

- BIGNUM=no

- BIGNUM=no ENDOMORPHISM=yes RECOVERY=yes EXPERIMENTAL=yes

- BIGNUM=no STATICPRECOMPUTATION=no

- BUILD=distcheck

- EXTRAFLAGS=CPPFLAGS=-DDETERMINISTIC

- EXTRAFLAGS=CFLAGS=-O0

- BUILD=check-java JNI=yes ECDH=yes EXPERIMENTAL=yes

matrix:

fast_finish: true

include:

- compiler: clang

env: HOST=i686-linux-gnu ENDOMORPHISM=yes

addons:

apt:

packages:

- gcc-multilib

- libgmp-dev:i386

- compiler: clang

env: HOST=i686-linux-gnu

addons:

apt:

packages:

- gcc-multilib

- compiler: gcc

env: HOST=i686-linux-gnu ENDOMORPHISM=yes

addons:

apt:

packages:

- gcc-multilib

- compiler: gcc

env: HOST=i686-linux-gnu

addons:

apt:

packages:

- gcc-multilib

- libgmp-dev:i386

before_install: mkdir -p `dirname $GUAVA_JAR`

install: if [ ! -f $GUAVA_JAR ]; then wget $GUAVA_URL -O $GUAVA_JAR; fi

before_script: ./autogen.sh

script:

- if [ -n "$HOST" ]; then export USE_HOST="--host=$HOST"; fi

- if [ "x$HOST" = "xi686-linux-gnu" ]; then export CC="$CC -m32"; fi

- ./configure --enable-experimental=$EXPERIMENTAL --enable-endomorphism=$ENDOMORPHISM --with-field=$FIELD --with-bignum=$BIGNUM --with-scalar=$SCALAR --enable-ecmult-static-precomputation=$STATICPRECOMPUTATION --enable-module-ecdh=$ECDH --enable-module-recovery=$RECOVERY --enable-jni=$JNI $EXTRAFLAGS $USE_HOST && make -j2 $BUILD

os: linux

Copyright (c) 2013 Pieter Wuille

Permission is hereby granted, free of charge, to any person obtaining a copy

of this software and associated documentation files (the "Software"), to deal

in the Software without restriction, including without limitation the rights

to use, copy, modify, merge, publish, distribute, sublicense, and/or sell

copies of the Software, and to permit persons to whom the Software is

furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in

all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE

AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,

OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN

THE SOFTWARE.

ACLOCAL_AMFLAGS = -I build-aux/m4

lib_LTLIBRARIES = libsecp256k1.la

if USE_JNI

JNI_LIB = libsecp256k1_jni.la

noinst_LTLIBRARIES = $(JNI_LIB)

else

JNI_LIB =

endif

include_HEADERS = include/secp256k1.h

noinst_HEADERS =

noinst_HEADERS += src/scalar.h

noinst_HEADERS += src/scalar_4x64.h

noinst_HEADERS += src/scalar_8x32.h

noinst_HEADERS += src/scalar_low.h

noinst_HEADERS += src/scalar_impl.h

noinst_HEADERS += src/scalar_4x64_impl.h

noinst_HEADERS += src/scalar_8x32_impl.h

noinst_HEADERS += src/scalar_low_impl.h

noinst_HEADERS += src/group.h

noinst_HEADERS += src/group_impl.h

noinst_HEADERS += src/num_gmp.h

noinst_HEADERS += src/num_gmp_impl.h

noinst_HEADERS += src/ecdsa.h

noinst_HEADERS += src/ecdsa_impl.h

noinst_HEADERS += src/eckey.h

noinst_HEADERS += src/eckey_impl.h

noinst_HEADERS += src/ecmult.h

noinst_HEADERS += src/ecmult_impl.h

noinst_HEADERS += src/ecmult_const.h

noinst_HEADERS += src/ecmult_const_impl.h

noinst_HEADERS += src/ecmult_gen.h

noinst_HEADERS += src/ecmult_gen_impl.h

noinst_HEADERS += src/num.h

noinst_HEADERS += src/num_impl.h

noinst_HEADERS += src/field_10x26.h

noinst_HEADERS += src/field_10x26_impl.h

noinst_HEADERS += src/field_5x52.h

noinst_HEADERS += src/field_5x52_impl.h

noinst_HEADERS += src/field_5x52_int128_impl.h

noinst_HEADERS += src/field_5x52_asm_impl.h

noinst_HEADERS += src/java/org_bitcoin_NativeSecp256k1.h

noinst_HEADERS += src/java/org_bitcoin_Secp256k1Context.h

noinst_HEADERS += src/util.h

noinst_HEADERS += src/scratch.h

noinst_HEADERS += src/scratch_impl.h

noinst_HEADERS += src/testrand.h

noinst_HEADERS += src/testrand_impl.h

noinst_HEADERS += src/hash.h

noinst_HEADERS += src/hash_impl.h

noinst_HEADERS += src/field.h

noinst_HEADERS += src/field_impl.h

noinst_HEADERS += src/bench.h

noinst_HEADERS += contrib/lax_der_parsing.h

noinst_HEADERS += contrib/lax_der_parsing.c

noinst_HEADERS += contrib/lax_der_privatekey_parsing.h

noinst_HEADERS += contrib/lax_der_privatekey_parsing.c

if USE_EXTERNAL_ASM

COMMON_LIB = libsecp256k1_common.la

noinst_LTLIBRARIES = $(COMMON_LIB)

else

COMMON_LIB =

endif

pkgconfigdir = $(libdir)/pkgconfig

pkgconfig_DATA = libsecp256k1.pc

if USE_EXTERNAL_ASM

if USE_ASM_ARM

libsecp256k1_common_la_SOURCES = src/asm/field_10x26_arm.s

endif

endif

libsecp256k1_la_SOURCES = src/secp256k1.c

libsecp256k1_la_CPPFLAGS = -DSECP256K1_BUILD -I$(top_srcdir)/include -I$(top_srcdir)/src $(SECP_INCLUDES)

libsecp256k1_la_LIBADD = $(JNI_LIB) $(SECP_LIBS) $(COMMON_LIB)

libsecp256k1_jni_la_SOURCES = src/java/org_bitcoin_NativeSecp256k1.c src/java/org_bitcoin_Secp256k1Context.c

libsecp256k1_jni_la_CPPFLAGS = -DSECP256K1_BUILD $(JNI_INCLUDES)

noinst_PROGRAMS =

if USE_BENCHMARK

noinst_PROGRAMS += bench_verify bench_sign bench_internal bench_ecmult

bench_verify_SOURCES = src/bench_verify.c

bench_verify_LDADD = libsecp256k1.la $(SECP_LIBS) $(SECP_TEST_LIBS) $(COMMON_LIB)

bench_sign_SOURCES = src/bench_sign.c

bench_sign_LDADD = libsecp256k1.la $(SECP_LIBS) $(SECP_TEST_LIBS) $(COMMON_LIB)

bench_internal_SOURCES = src/bench_internal.c

bench_internal_LDADD = $(SECP_LIBS) $(COMMON_LIB)

bench_internal_CPPFLAGS = -DSECP256K1_BUILD $(SECP_INCLUDES)

bench_ecmult_SOURCES = src/bench_ecmult.c

bench_ecmult_LDADD = $(SECP_LIBS) $(COMMON_LIB)

bench_ecmult_CPPFLAGS = -DSECP256K1_BUILD $(SECP_INCLUDES)

endif

TESTS =

if USE_TESTS

noinst_PROGRAMS += tests

tests_SOURCES = src/tests.c

tests_CPPFLAGS = -DSECP256K1_BUILD -I$(top_srcdir)/src -I$(top_srcdir)/include $(SECP_INCLUDES) $(SECP_TEST_INCLUDES)

if !ENABLE_COVERAGE

tests_CPPFLAGS += -DVERIFY

endif

tests_LDADD = $(SECP_LIBS) $(SECP_TEST_LIBS) $(COMMON_LIB)

tests_LDFLAGS = -static

TESTS += tests

endif

if USE_EXHAUSTIVE_TESTS

noinst_PROGRAMS += exhaustive_tests

exhaustive_tests_SOURCES = src/tests_exhaustive.c

exhaustive_tests_CPPFLAGS = -DSECP256K1_BUILD -I$(top_srcdir)/src $(SECP_INCLUDES)

if !ENABLE_COVERAGE

exhaustive_tests_CPPFLAGS += -DVERIFY

endif

exhaustive_tests_LDADD = $(SECP_LIBS)

exhaustive_tests_LDFLAGS = -static

TESTS += exhaustive_tests

endif

JAVAROOT=src/java

JAVAORG=org/bitcoin

JAVA_GUAVA=$(srcdir)/$(JAVAROOT)/guava/guava-18.0.jar

CLASSPATH_ENV=CLASSPATH=$(JAVA_GUAVA)

JAVA_FILES= \

$(JAVAROOT)/$(JAVAORG)/NativeSecp256k1.java \

$(JAVAROOT)/$(JAVAORG)/NativeSecp256k1Test.java \

$(JAVAROOT)/$(JAVAORG)/NativeSecp256k1Util.java \

$(JAVAROOT)/$(JAVAORG)/Secp256k1Context.java

if USE_JNI

$(JAVA_GUAVA):

@echo Guava is missing. Fetch it via: \

wget https://search.maven.org/remotecontent?filepath=com/google/guava/guava/18.0/guava-18.0.jar -O $(@)

@false

.stamp-java: $(JAVA_FILES)

@echo Compiling $^

$(AM_V_at)$(CLASSPATH_ENV) javac $^

@touch $@

if USE_TESTS

check-java: libsecp256k1.la $(JAVA_GUAVA) .stamp-java

$(AM_V_at)java -Djava.library.path="./:./src:./src/.libs:.libs/" -cp "$(JAVA_GUAVA):$(JAVAROOT)" $(JAVAORG)/NativeSecp256k1Test

endif

endif

if USE_ECMULT_STATIC_PRECOMPUTATION

CPPFLAGS_FOR_BUILD +=-I$(top_srcdir)

CFLAGS_FOR_BUILD += -Wall -Wextra -Wno-unused-function

gen_context_OBJECTS = gen_context.o

gen_context_BIN = gen_context$(BUILD_EXEEXT)

gen_%.o: src/gen_%.c

$(CC_FOR_BUILD) $(CPPFLAGS_FOR_BUILD) $(CFLAGS_FOR_BUILD) -c $< -o $@

$(gen_context_BIN): $(gen_context_OBJECTS)

$(CC_FOR_BUILD) $^ -o $@

$(libsecp256k1_la_OBJECTS): src/ecmult_static_context.h

$(tests_OBJECTS): src/ecmult_static_context.h

$(bench_internal_OBJECTS): src/ecmult_static_context.h

$(bench_ecmult_OBJECTS): src/ecmult_static_context.h

src/ecmult_static_context.h: $(gen_context_BIN)

./$(gen_context_BIN)

CLEANFILES = $(gen_context_BIN) src/ecmult_static_context.h $(JAVAROOT)/$(JAVAORG)/*.class .stamp-java

endif

EXTRA_DIST = autogen.sh src/gen_context.c src/basic-config.h $(JAVA_FILES)

if ENABLE_MODULE_ECDH

include src/modules/ecdh/Makefile.am.include

endif

if ENABLE_MODULE_RECOVERY

include src/modules/recovery/Makefile.am.include

endif

libsecp256k1

[](https://travis-ci.org/bitcoin-core/secp256k1)

Optimized C library for EC operations on curve secp256k1.

This library is a work in progress and is being used to research best practices. Use at your own risk.

Features:

* secp256k1 ECDSA signing/verification and key generation.

* Adding/multiplying private/public keys.

* Serialization/parsing of private keys, public keys, signatures.

* Constant time, constant memory access signing and pubkey generation.

* Derandomized DSA (via RFC6979 or with a caller provided function.)

* Very efficient implementation.

Implementation details

* General

* No runtime heap allocation.

* Extensive testing infrastructure.

* Structured to facilitate review and analysis.

* Intended to be portable to any system with a C89 compiler and uint64_t support.

* Expose only higher level interfaces to minimize the API surface and improve application security. ("Be difficult to use insecurely.")

* Field operations

* Optimized implementation of arithmetic modulo the curve's field size (2^256 - 0x1000003D1).

* Using 5 52-bit limbs (including hand-optimized assembly for x86_64, by Diederik Huys).

* Using 10 26-bit limbs.

* Field inverses and square roots using a sliding window over blocks of 1s (by Peter Dettman).

* Scalar operations

* Optimized implementation without data-dependent branches of arithmetic modulo the curve's order.

* Using 4 64-bit limbs (relying on __int128 support in the compiler).

* Using 8 32-bit limbs.

* Group operations

* Point addition formula specifically simplified for the curve equation (y^2 = x^3 + 7).

* Use addition between points in Jacobian and affine coordinates where possible.

* Use a unified addition/doubling formula where necessary to avoid data-dependent branches.

* Point/x comparison without a field inversion by comparison in the Jacobian coordinate space.

* Point multiplication for verification (a*P + b*G).

* Use wNAF notation for point multiplicands.

* Use a much larger window for multiples of G, using precomputed multiples.

* Use Shamir's trick to do the multiplication with the public key and the generator simultaneously.

* Optionally (off by default) use secp256k1's efficiently-computable endomorphism to split the P multiplicand into 2 half-sized ones.

* Point multiplication for signing

* Use a precomputed table of multiples of powers of 16 multiplied with the generator, so general multiplication becomes a series of additions.

* Access the table with branch-free conditional moves so memory access is uniform.

* No data-dependent branches

* The precomputed tables add and eventually subtract points for which no known scalar (private key) is known, preventing even an attacker with control over the private key used to control the data internally.

Build steps

libsecp256k1 is built using autotools:

$ ./autogen.sh

$ ./configure

$ make

$ ./tests

$ sudo make install # optional

* Unit tests for fieldelem/groupelem, including ones intended to

trigger fieldelem's boundary cases.

* Complete constant-time operations for signing/keygen

set -e

autoreconf -if --warnings=all