#23432 bip324-ellsq

build_msvc/libsecp256k1/libsecp256k1.vcxproj

@@ -14,7 +14,7 @@
   </ItemGroup>
   <ItemDefinitionGroup>
     <ClCompile>
-      <PreprocessorDefinitions>ENABLE_MODULE_RECOVERY;ENABLE_MODULE_EXTRAKEYS;ENABLE_MODULE_SCHNORRSIG;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>ENABLE_MODULE_RECOVERY;ENABLE_MODULE_EXTRAKEYS;ENABLE_MODULE_SCHNORRSIG;ENABLE_MODULE_ELLSWIFT;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <AdditionalIncludeDirectories>..\..\src\secp256k1;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
       <DisableSpecificWarnings>4146;4244;4267;4334</DisableSpecificWarnings>
     </ClCompile>

configure.ac

@@ -1989,7 +1989,7 @@ CPPFLAGS_TEMP="$CPPFLAGS"
 unset CPPFLAGS
 CPPFLAGS="$CPPFLAGS_TEMP"
 
-ac_configure_args="${ac_configure_args} --disable-shared --with-pic --enable-benchmark=no --enable-module-recovery --disable-module-ecdh"
+ac_configure_args="${ac_configure_args} --disable-shared --with-pic --enable-benchmark=no --enable-module-recovery --disable-module-ecdh --enable-experimental --enable-module-ellswift"
 AC_CONFIG_SUBDIRS([src/secp256k1])
 
 AC_OUTPUT

src/Makefile.bench.include

@@ -29,6 +29,7 @@ bench_bench_bitcoin_SOURCES = \
   bench/data.h \
   bench/descriptors.cpp \
   bench/duplicate_inputs.cpp \
+  bench/ellswift.cpp \
   bench/examples.cpp \
   bench/gcs_filter.cpp \
   bench/hashpadding.cpp \

src/bench/ellswift.cpp

@@ -0,0 +1,28 @@
+// Copyright (c) 2016-2020 The Bitcoin Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#include <bench/bench.h>
+
+#include <key.h>
+#include <random.h>
+
+#include <array>
+#include <cstddef>
+
+static void EllSwiftEncode(benchmark::Bench& bench)
+{
+    ECC_Start();
+
+    CKey key;
+    key.MakeNewKey(true);
+
+    bench.batch(1).unit("pubkey").run([&] {
+        std::array<std::byte, 32> rnd32;
+        GetRandBytes({reinterpret_cast<unsigned char*>(rnd32.data()), 32});
+        key.EllSwiftEncode(rnd32);
+    });
+    ECC_Stop();
+}
+
+BENCHMARK(EllSwiftEncode, benchmark::PriorityLevel::HIGH);

src/key.cpp

@@ -9,8 +9,10 @@
 #include <crypto/hmac_sha512.h>
 #include <hash.h>
 #include <random.h>
+#include <span.h>
 
 #include <secp256k1.h>
+#include <secp256k1_ellswift.h>
 #include <secp256k1_extrakeys.h>
 #include <secp256k1_recovery.h>
 #include <secp256k1_schnorrsig.h>
@@ -331,6 +333,21 @@ bool CKey::Derive(CKey& keyChild, ChainCode &ccChild, unsigned int nChild, const
     return ret;
 }
 
+EllSwiftPubKey CKey::EllSwiftEncode(const std::array<std::byte, 32>& rnd32) const
+{
+    assert(fValid);
+    EllSwiftPubKey encoded_pubkey;
+
+    auto success = secp256k1_ellswift_create(secp256k1_context_sign,
+                                             reinterpret_cast<unsigned char*>(encoded_pubkey.data()),
+                                             keydata.data(),
+                                             UCharCast(rnd32.data()));
+
+    // Should always succeed for valid keys (asserted above)
+    assert(success);
+    return encoded_pubkey;
+}
+
 bool CExtKey::Derive(CExtKey &out, unsigned int _nChild) const {
     if (nDepth == std::numeric_limits<unsigned char>::max()) return false;
     out.nDepth = nDepth + 1;

src/key.h

@@ -12,6 +12,8 @@
 #include <support/allocators/secure.h>
 #include <uint256.h>
 
+#include <array>
+#include <cstddef>
 #include <stdexcept>
 #include <vector>
 
@@ -156,6 +158,8 @@ class CKey
 
     //! Load private key and check that public key matches.
     bool Load(const CPrivKey& privkey, const CPubKey& vchPubKey, bool fSkipCheck);
+
+    EllSwiftPubKey EllSwiftEncode(const std::array<std::byte, 32>& rnd32) const;
 };
 
 struct CExtKey {

src/pubkey.h

@@ -12,6 +12,8 @@
 #include <span.h>
 #include <uint256.h>
 
+#include <array>
+#include <cstddef>
 #include <cstring>
 #include <optional>
 #include <vector>
@@ -29,6 +31,9 @@ class CKeyID : public uint160
 
 typedef uint256 ChainCode;
 
+constexpr size_t ELLSWIFT_ENCODED_SIZE = 64;
+using EllSwiftPubKey = std::array<std::byte, ELLSWIFT_ENCODED_SIZE>;
+
 /** An encapsulated public key. */
 class CPubKey
 {

src/secp256k1/.cirrus.yml

@@ -21,6 +21,7 @@ env:
   ECDH: no
   RECOVERY: no
   SCHNORRSIG: no
+  ELLSWIFT: no
   ### test options
   SECP256K1_TEST_ITERS:
   BENCH: yes
@@ -74,12 +75,12 @@ task:
   << : *LINUX_CONTAINER
   matrix: &ENV_MATRIX
     - env: {WIDEMUL:  int64,  RECOVERY: yes}
-    - env: {WIDEMUL:  int64,                 ECDH: yes, SCHNORRSIG: yes}
+    - env: {WIDEMUL:  int64,                 ECDH: yes, SCHNORRSIG: yes, ELLSWIFT: yes}
     - env: {WIDEMUL: int128}
-    - env: {WIDEMUL: int128_struct}
-    - env: {WIDEMUL: int128,  RECOVERY: yes,            SCHNORRSIG: yes}
+    - env: {WIDEMUL: int128_struct,                                      ELLSWIFT: yes}
+    - env: {WIDEMUL: int128,  RECOVERY: yes,            SCHNORRSIG: yes, ELLSWIFT: yes}
     - env: {WIDEMUL: int128,                 ECDH: yes, SCHNORRSIG: yes}
-    - env: {WIDEMUL: int128,  ASM: x86_64}
+    - env: {WIDEMUL: int128,  ASM: x86_64                              , ELLSWIFT: yes}
     - env: {                  RECOVERY: yes,            SCHNORRSIG: yes}
     - env: {CTIMETESTS: no,    RECOVERY: yes, ECDH: yes, SCHNORRSIG: yes, CPPFLAGS: -DVERIFY}
     - env: {BUILD: distcheck, WITH_VALGRIND: no, CTIMETESTS: no, BENCH: no}
@@ -154,6 +155,7 @@ task:
     ECDH: yes
     RECOVERY: yes
     SCHNORRSIG: yes
+    ELLSWIFT: yes
     CTIMETESTS: no
   << : *MERGE_BASE
   test_script:
@@ -173,6 +175,7 @@ task:
     ECDH: yes
     RECOVERY: yes
     SCHNORRSIG: yes
+    ELLSWIFT: yes
     CTIMETESTS: no
   matrix:
     - env: {}
@@ -193,6 +196,7 @@ task:
     ECDH: yes
     RECOVERY: yes
     SCHNORRSIG: yes
+    ELLSWIFT: yes
     CTIMETESTS: no
   << : *MERGE_BASE
   test_script:
@@ -210,6 +214,7 @@ task:
     ECDH: yes
     RECOVERY: yes
     SCHNORRSIG: yes
+    ELLSWIFT: yes
     CTIMETESTS: no
   << : *MERGE_BASE
   test_script:
@@ -247,6 +252,7 @@ task:
     RECOVERY: yes
     EXPERIMENTAL: yes
     SCHNORRSIG: yes
+    ELLSWIFT: yes
     CTIMETESTS: no
     # Use a MinGW-w64 host to tell ./configure we're building for Windows.
     # This will detect some MinGW-w64 tools but then make will need only
@@ -286,6 +292,7 @@ task:
     ECDH: yes
     RECOVERY: yes
     SCHNORRSIG: yes
+    ELLSWIFT: yes
     CTIMETESTS: no
   matrix:
     - name: "Valgrind (memcheck)"
@@ -361,6 +368,7 @@ task:
     ECDH: yes
     RECOVERY: yes
     SCHNORRSIG: yes
+    ELLSWIFT: yes
   << : *MERGE_BASE
   test_script:
     - ./ci/cirrus.sh

src/secp256k1/CMakeLists.txt

@@ -10,15 +10,15 @@ endif()
 # The package (a.k.a. release) version is based on semantic versioning 2.0.0 of
 # the API. All changes in experimental modules are treated as
 # backwards-compatible and therefore at most increase the minor version.
-project(libsecp256k1 VERSION 0.3.0 LANGUAGES C)
+project(libsecp256k1 VERSION 0.3.1 LANGUAGES C)
 
 # The library version is based on libtool versioning of the ABI. The set of
 # rules for updating the version can be found here:
 # https://www.gnu.org/software/libtool/manual/html_node/Updating-version-info.html
 # All changes in experimental modules are treated as if they don't affect the
 # interface and therefore only increase the revision.
 set(${PROJECT_NAME}_LIB_VERSION_CURRENT 2)
-set(${PROJECT_NAME}_LIB_VERSION_REVISION 0)
+set(${PROJECT_NAME}_LIB_VERSION_REVISION 1)
 set(${PROJECT_NAME}_LIB_VERSION_AGE 0)
 
 set(CMAKE_C_STANDARD 90)

src/secp256k1/Makefile.am

@@ -247,3 +247,7 @@ endif
 if ENABLE_MODULE_SCHNORRSIG
 include src/modules/schnorrsig/Makefile.am.include
 endif
+
+if ENABLE_MODULE_ELLSWIFT
+include src/modules/ellswift/Makefile.am.include
+endif

src/secp256k1/ci/cirrus.sh

@@ -62,6 +62,7 @@ fi
     --with-ecmult-window="$ECMULTWINDOW" \
     --with-ecmult-gen-precision="$ECMULTGENPRECISION" \
     --enable-module-ecdh="$ECDH" --enable-module-recovery="$RECOVERY" \
+    --enable-module-ellswift="$ELLSWIFT" \
     --enable-module-schnorrsig="$SCHNORRSIG" \
     --enable-examples="$EXAMPLES" \
     --enable-ctime-tests="$CTIMETESTS" \

src/secp256k1/configure.ac

@@ -5,16 +5,16 @@ AC_PREREQ([2.60])
 # backwards-compatible and therefore at most increase the minor version.
 define(_PKG_VERSION_MAJOR, 0)
 define(_PKG_VERSION_MINOR, 3)
-define(_PKG_VERSION_PATCH, 0)
-define(_PKG_VERSION_IS_RELEASE, true)
+define(_PKG_VERSION_PATCH, 1)
+define(_PKG_VERSION_IS_RELEASE, false)
 
 # The library version is based on libtool versioning of the ABI. The set of
 # rules for updating the version can be found here:
 # https://www.gnu.org/software/libtool/manual/html_node/Updating-version-info.html
 # All changes in experimental modules are treated as if they don't affect the
 # interface and therefore only increase the revision.
 define(_LIB_VERSION_CURRENT, 2)
-define(_LIB_VERSION_REVISION, 0)
+define(_LIB_VERSION_REVISION, 1)
 define(_LIB_VERSION_AGE, 0)
 
 AC_INIT([libsecp256k1],m4_join([.], _PKG_VERSION_MAJOR, _PKG_VERSION_MINOR, _PKG_VERSION_PATCH)m4_if(_PKG_VERSION_IS_RELEASE, [true], [], [-dev]),[https://github.com/bitcoin-core/secp256k1/issues],[libsecp256k1],[https://github.com/bitcoin-core/secp256k1])
@@ -178,6 +178,11 @@ AC_ARG_ENABLE(module_schnorrsig,
     AS_HELP_STRING([--enable-module-schnorrsig],[enable schnorrsig module [default=yes]]), [],
     [SECP_SET_DEFAULT([enable_module_schnorrsig], [yes], [yes])])
 
+AC_ARG_ENABLE(module_ellswift,
+    AS_HELP_STRING([--enable-module-ellswift],[enable ElligatorSwift module (experimental)]),
+    [enable_module_ellswift=$enableval],
+    [enable_module_ellswift=no])
+
 AC_ARG_ENABLE(external_default_callbacks,
     AS_HELP_STRING([--enable-external-default-callbacks],[enable external default callback functions [default=no]]), [],
     [SECP_SET_DEFAULT([enable_external_default_callbacks], [no], [no])])
@@ -380,6 +385,10 @@ if test x"$enable_module_schnorrsig" = x"yes"; then
   enable_module_extrakeys=yes
 fi
 
+if test x"$enable_module_ellswift" = x"yes"; then
+  AC_DEFINE(ENABLE_MODULE_ELLSWIFT, 1, [Define this symbol to enable the ElligatorSwift module])
+fi
+
 # Test if extrakeys is set after the schnorrsig module to allow the schnorrsig
 # module to set enable_module_extrakeys=yes
 if test x"$enable_module_extrakeys" = x"yes"; then
@@ -422,6 +431,7 @@ AM_CONDITIONAL([ENABLE_MODULE_ECDH], [test x"$enable_module_ecdh" = x"yes"])
 AM_CONDITIONAL([ENABLE_MODULE_RECOVERY], [test x"$enable_module_recovery" = x"yes"])
 AM_CONDITIONAL([ENABLE_MODULE_EXTRAKEYS], [test x"$enable_module_extrakeys" = x"yes"])
 AM_CONDITIONAL([ENABLE_MODULE_SCHNORRSIG], [test x"$enable_module_schnorrsig" = x"yes"])
+AM_CONDITIONAL([ENABLE_MODULE_ELLSWIFT], [test x"$enable_module_ellswift" = x"yes"])
 AM_CONDITIONAL([USE_EXTERNAL_ASM], [test x"$enable_external_asm" = x"yes"])
 AM_CONDITIONAL([USE_ASM_ARM], [test x"$set_asm" = x"arm"])
 AM_CONDITIONAL([BUILD_WINDOWS], [test "$build_windows" = "yes"])
@@ -443,6 +453,7 @@ echo "  module ecdh             = $enable_module_ecdh"
 echo "  module recovery         = $enable_module_recovery"
 echo "  module extrakeys        = $enable_module_extrakeys"
 echo "  module schnorrsig       = $enable_module_schnorrsig"
+echo "  module ellswift         = $enable_module_ellswift"
 echo
 echo "  asm                     = $set_asm"
 echo "  ecmult window size      = $set_ecmult_window"