New Experimental Module: Incremental Half-Aggregation for Schnorr Sig…

…natures
BlockstreamResearch · Nov 26, 2023 · 959b070 · 959b070
1 parent eb4fb6d
commit 959b070
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diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
@@ -32,6 +32,7 @@ env:
   ECDH: 'no'
   RECOVERY: 'no'
   SCHNORRSIG: 'no'
+  SCHNORRSIG_HALFAGG: 'no'
   ELLSWIFT: 'no'
   ECDSA_S2C: 'no'
   GENERATOR: 'no'
@@ -78,14 +79,14 @@ jobs:
       matrix:
         configuration:
           - env_vars: { WIDEMUL: 'int64',  RECOVERY: 'yes' }
-          - env_vars: { WIDEMUL: 'int64',                   ECDH: 'yes', SCHNORRSIG: 'yes', ELLSWIFT: 'yes', EXPERIMENTAL: 'yes', ECDSA_S2C: 'yes',  RANGEPROOF: 'yes', WHITELIST: 'yes', GENERATOR: 'yes', MUSIG: 'yes', ECDSAADAPTOR: 'yes', BPPP: 'yes' }
+          - env_vars: { WIDEMUL: 'int64',                   ECDH: 'yes', SCHNORRSIG: 'yes', SCHNORRSIG_HALFAGG: 'yes', ELLSWIFT: 'yes', EXPERIMENTAL: 'yes', ECDSA_S2C: 'yes',  RANGEPROOF: 'yes', WHITELIST: 'yes', GENERATOR: 'yes', MUSIG: 'yes', ECDSAADAPTOR: 'yes', BPPP: 'yes' }
           - env_vars: { WIDEMUL: 'int128' }
           - env_vars: { WIDEMUL: 'int128_struct',                                           ELLSWIFT: 'yes' }
           - env_vars: { WIDEMUL: 'int128', RECOVERY: 'yes',              SCHNORRSIG: 'yes', ELLSWIFT: 'yes' }
-          - env_vars: { WIDEMUL: 'int128',                  ECDH: 'yes', SCHNORRSIG: 'yes', EXPERIMENTAL: 'yes', ECDSA_S2C: 'yes', RANGEPROOF: 'yes', WHITELIST: 'yes', GENERATOR: 'yes', MUSIG: 'yes', ECDSAADAPTOR: 'yes', BPPP: 'yes'}
+          - env_vars: { WIDEMUL: 'int128',                  ECDH: 'yes', SCHNORRSIG: 'yes', SCHNORRSIG_HALFAGG: 'yes', EXPERIMENTAL: 'yes', ECDSA_S2C: 'yes', RANGEPROOF: 'yes', WHITELIST: 'yes', GENERATOR: 'yes', MUSIG: 'yes', ECDSAADAPTOR: 'yes', BPPP: 'yes'}
           - env_vars: { WIDEMUL: 'int128', ASM: 'x86_64',                                   ELLSWIFT: 'yes' }
-          - env_vars: {                    RECOVERY: 'yes',              SCHNORRSIG: 'yes', EXPERIMENTAL: 'yes', ECDSA_S2C: 'yes', RANGEPROOF: 'yes', WHITELIST: 'yes', GENERATOR: 'yes', MUSIG: 'yes', ECDSAADAPTOR: 'yes', BPPP: 'yes'}
-          - env_vars: { CTIMETESTS: 'no',  RECOVERY: 'yes', ECDH: 'yes', SCHNORRSIG: 'yes', EXPERIMENTAL: 'yes', ECDSA_S2C: 'yes', RANGEPROOF: 'yes', WHITELIST: 'yes', GENERATOR: 'yes', MUSIG: 'yes', ECDSAADAPTOR: 'yes', BPPP: 'yes', CPPFLAGS: '-DVERIFY' }
+          - env_vars: {                    RECOVERY: 'yes',              SCHNORRSIG: 'yes', SCHNORRSIG_HALFAGG: 'yes', EXPERIMENTAL: 'yes', ECDSA_S2C: 'yes', RANGEPROOF: 'yes', WHITELIST: 'yes', GENERATOR: 'yes', MUSIG: 'yes', ECDSAADAPTOR: 'yes', BPPP: 'yes'}
+          - env_vars: { CTIMETESTS: 'no',  RECOVERY: 'yes', ECDH: 'yes', SCHNORRSIG: 'yes', SCHNORRSIG_HALFAGG: 'yes', EXPERIMENTAL: 'yes', ECDSA_S2C: 'yes', RANGEPROOF: 'yes', WHITELIST: 'yes', GENERATOR: 'yes', MUSIG: 'yes', ECDSAADAPTOR: 'yes', BPPP: 'yes', CPPFLAGS: '-DVERIFY' }
           - env_vars: { BUILD: 'distcheck', WITH_VALGRIND: 'no', CTIMETESTS: 'no', BENCH: 'no' }
           - env_vars: { CPPFLAGS: '-DDETERMINISTIC' }
           - env_vars: { CFLAGS: '-O0', CTIMETESTS: 'no' }
@@ -147,6 +148,7 @@ jobs:
       ECDH: 'yes'
       RECOVERY: 'yes'
       SCHNORRSIG: 'yes'
+      SCHNORRSIG_HALFAGG: 'yes'
       ELLSWIFT: 'yes'
       EXPERIMENTAL: 'yes'
       ECDSA_S2C: 'yes'
@@ -199,6 +201,7 @@ jobs:
       ECDH: 'yes'
       RECOVERY: 'yes'
       SCHNORRSIG: 'yes'
+      SCHNORRSIG_HALFAGG: 'yes'
       ELLSWIFT: 'yes'
       EXPERIMENTAL: 'yes'
       ECDSA_S2C: 'yes'
@@ -258,6 +261,7 @@ jobs:
       ECDH: 'yes'
       RECOVERY: 'yes'
       SCHNORRSIG: 'yes'
+      SCHNORRSIG_HALFAGG: 'yes'
       ELLSWIFT: 'yes'
       EXPERIMENTAL: 'yes'
       ECDSA_S2C: 'yes'
@@ -311,6 +315,7 @@ jobs:
       ECDH: 'yes'
       RECOVERY: 'yes'
       SCHNORRSIG: 'yes'
+      SCHNORRSIG_HALFAGG: 'yes'
       ELLSWIFT: 'yes'
       EXPERIMENTAL: 'yes'
       ECDSA_S2C: 'yes'
@@ -374,6 +379,7 @@ jobs:
       ECDH: 'yes'
       RECOVERY: 'yes'
       SCHNORRSIG: 'yes'
+      SCHNORRSIG_HALFAGG: 'yes'
       ELLSWIFT: 'yes'
       EXPERIMENTAL: 'yes'
       ECDSA_S2C: 'yes'
@@ -434,6 +440,7 @@ jobs:
       ECDH: 'yes'
       RECOVERY: 'yes'
       SCHNORRSIG: 'yes'
+      SCHNORRSIG_HALFAGG: 'yes'
       ELLSWIFT: 'yes'
       EXPERIMENTAL: 'yes'
       ECDSA_S2C: 'yes'
@@ -493,6 +500,7 @@ jobs:
       ECDH: 'yes'
       RECOVERY: 'yes'
       SCHNORRSIG: 'yes'
+      SCHNORRSIG_HALFAGG: 'yes'
       ELLSWIFT: 'yes'
       EXPERIMENTAL: 'yes'
       ECDSA_S2C: 'yes'
@@ -558,6 +566,7 @@ jobs:
       ECDH: 'yes'
       RECOVERY: 'yes'
       SCHNORRSIG: 'yes'
+      SCHNORRSIG_HALFAGG: 'yes'
       ELLSWIFT: 'yes'
       EXPERIMENTAL: 'yes'
       ECDSA_S2C: 'yes'
@@ -613,6 +622,7 @@ jobs:
       ECDH: 'yes'
       RECOVERY: 'yes'
       SCHNORRSIG: 'yes'
+      SCHNORRSIG_HALFAGG: 'yes'
       ELLSWIFT: 'yes'
       EXPERIMENTAL: 'yes'
       ECDSA_S2C: 'yes'
@@ -678,15 +688,15 @@ jobs:
       fail-fast: false
       matrix:
         env_vars:
-          - { WIDEMUL: 'int64',  RECOVERY: 'yes', ECDH: 'yes', SCHNORRSIG: 'yes', ELLSWIFT: 'yes', EXPERIMENTAL: 'yes', ECDSA_S2C: 'yes', RANGEPROOF: 'yes', WHITELIST: 'yes', GENERATOR: 'yes', MUSIG: 'yes', ECDSAADAPTOR: 'yes', BPPP: 'yes' }
+          - { WIDEMUL: 'int64',  RECOVERY: 'yes', ECDH: 'yes', SCHNORRSIG: 'yes', SCHNORRSIG_HALFAGG: 'yes', ELLSWIFT: 'yes', EXPERIMENTAL: 'yes', ECDSA_S2C: 'yes', RANGEPROOF: 'yes', WHITELIST: 'yes', GENERATOR: 'yes', MUSIG: 'yes', ECDSAADAPTOR: 'yes', BPPP: 'yes' }
           - { WIDEMUL: 'int128_struct', ECMULTGENPRECISION: 2, ECMULTWINDOW: 4 }
-          - { WIDEMUL: 'int128',                  ECDH: 'yes', SCHNORRSIG: 'yes', ELLSWIFT: 'yes', EXPERIMENTAL: 'yes', ECDSA_S2C: 'yes', RANGEPROOF: 'yes', WHITELIST: 'yes', GENERATOR: 'yes', MUSIG: 'yes', ECDSAADAPTOR: 'yes', BPPP: 'yes' }
+          - { WIDEMUL: 'int128',                  ECDH: 'yes', SCHNORRSIG: 'yes', SCHNORRSIG_HALFAGG: 'yes', ELLSWIFT: 'yes', EXPERIMENTAL: 'yes', ECDSA_S2C: 'yes', RANGEPROOF: 'yes', WHITELIST: 'yes', GENERATOR: 'yes', MUSIG: 'yes', ECDSAADAPTOR: 'yes', BPPP: 'yes' }
           - { WIDEMUL: 'int128', RECOVERY: 'yes' }
-          - { WIDEMUL: 'int128', RECOVERY: 'yes', ECDH: 'yes', SCHNORRSIG: 'yes', ELLSWIFT: 'yes', EXPERIMENTAL: 'yes', ECDSA_S2C: 'yes', RANGEPROOF: 'yes', WHITELIST: 'yes', GENERATOR: 'yes', MUSIG: 'yes', ECDSAADAPTOR: 'yes', BPPP: 'yes' }
-          - { WIDEMUL: 'int128', RECOVERY: 'yes', ECDH: 'yes', SCHNORRSIG: 'yes', ELLSWIFT: 'yes', EXPERIMENTAL: 'yes', ECDSA_S2C: 'yes', RANGEPROOF: 'yes', WHITELIST: 'yes', GENERATOR: 'yes', MUSIG: 'yes', ECDSAADAPTOR: 'yes', BPPP: 'yes', CC: 'gcc' }
-          - { WIDEMUL: 'int128', RECOVERY: 'yes', ECDH: 'yes', SCHNORRSIG: 'yes', ELLSWIFT: 'yes', EXPERIMENTAL: 'yes', ECDSA_S2C: 'yes', RANGEPROOF: 'yes', WHITELIST: 'yes', GENERATOR: 'yes', MUSIG: 'yes', ECDSAADAPTOR: 'yes', BPPP: 'yes',            WRAPPER_CMD: 'valgrind --error-exitcode=42', SECP256K1_TEST_ITERS: 2 }
-          - { WIDEMUL: 'int128', RECOVERY: 'yes', ECDH: 'yes', SCHNORRSIG: 'yes', ELLSWIFT: 'yes', EXPERIMENTAL: 'yes', ECDSA_S2C: 'yes', RANGEPROOF: 'yes', WHITELIST: 'yes', GENERATOR: 'yes', MUSIG: 'yes', ECDSAADAPTOR: 'yes', BPPP: 'yes', CC: 'gcc', WRAPPER_CMD: 'valgrind --error-exitcode=42', SECP256K1_TEST_ITERS: 2 }
-          - { WIDEMUL: 'int128', RECOVERY: 'yes', ECDH: 'yes', SCHNORRSIG: 'yes', ELLSWIFT: 'yes', EXPERIMENTAL: 'yes', ECDSA_S2C: 'yes', RANGEPROOF: 'yes', WHITELIST: 'yes', GENERATOR: 'yes', MUSIG: 'yes', ECDSAADAPTOR: 'yes', BPPP: 'yes', CPPFLAGS: '-DVERIFY', CTIMETESTS: 'no' }
+          - { WIDEMUL: 'int128', RECOVERY: 'yes', ECDH: 'yes', SCHNORRSIG: 'yes', SCHNORRSIG_HALFAGG: 'yes', ELLSWIFT: 'yes', EXPERIMENTAL: 'yes', ECDSA_S2C: 'yes', RANGEPROOF: 'yes', WHITELIST: 'yes', GENERATOR: 'yes', MUSIG: 'yes', ECDSAADAPTOR: 'yes', BPPP: 'yes' }
+          - { WIDEMUL: 'int128', RECOVERY: 'yes', ECDH: 'yes', SCHNORRSIG: 'yes', SCHNORRSIG_HALFAGG: 'yes', ELLSWIFT: 'yes', EXPERIMENTAL: 'yes', ECDSA_S2C: 'yes', RANGEPROOF: 'yes', WHITELIST: 'yes', GENERATOR: 'yes', MUSIG: 'yes', ECDSAADAPTOR: 'yes', BPPP: 'yes', CC: 'gcc' }
+          - { WIDEMUL: 'int128', RECOVERY: 'yes', ECDH: 'yes', SCHNORRSIG: 'yes', SCHNORRSIG_HALFAGG: 'yes', ELLSWIFT: 'yes', EXPERIMENTAL: 'yes', ECDSA_S2C: 'yes', RANGEPROOF: 'yes', WHITELIST: 'yes', GENERATOR: 'yes', MUSIG: 'yes', ECDSAADAPTOR: 'yes', BPPP: 'yes',            WRAPPER_CMD: 'valgrind --error-exitcode=42', SECP256K1_TEST_ITERS: 2 }
+          - { WIDEMUL: 'int128', RECOVERY: 'yes', ECDH: 'yes', SCHNORRSIG: 'yes', SCHNORRSIG_HALFAGG: 'yes', ELLSWIFT: 'yes', EXPERIMENTAL: 'yes', ECDSA_S2C: 'yes', RANGEPROOF: 'yes', WHITELIST: 'yes', GENERATOR: 'yes', MUSIG: 'yes', ECDSAADAPTOR: 'yes', BPPP: 'yes', CC: 'gcc', WRAPPER_CMD: 'valgrind --error-exitcode=42', SECP256K1_TEST_ITERS: 2 }
+          - { WIDEMUL: 'int128', RECOVERY: 'yes', ECDH: 'yes', SCHNORRSIG: 'yes', SCHNORRSIG_HALFAGG: 'yes', ELLSWIFT: 'yes', EXPERIMENTAL: 'yes', ECDSA_S2C: 'yes', RANGEPROOF: 'yes', WHITELIST: 'yes', GENERATOR: 'yes', MUSIG: 'yes', ECDSAADAPTOR: 'yes', BPPP: 'yes', CPPFLAGS: '-DVERIFY', CTIMETESTS: 'no' }
           - BUILD: 'distcheck'
 
     steps:
@@ -796,6 +806,7 @@ jobs:
       ECDH: 'yes'
       RECOVERY: 'yes'
       SCHNORRSIG: 'yes'
+      SCHNORRSIG_HALFAGG: 'yes'
       ELLSWIFT: 'yes'
       EXPERIMENTAL: 'yes'
       ECDSA_S2C: 'yes'

diff --git a/Makefile.am b/Makefile.am
@@ -306,6 +306,10 @@ if ENABLE_MODULE_SCHNORRSIG
 include src/modules/schnorrsig/Makefile.am.include
 endif
 
+if ENABLE_MODULE_SCHNORRSIG_HALFAGG
+include src/modules/schnorrsig_halfagg/Makefile.am.include
+endif
+
 if ENABLE_MODULE_ELLSWIFT
 include src/modules/ellswift/Makefile.am.include
 endif

diff --git a/ci/ci.sh b/ci/ci.sh
@@ -13,7 +13,7 @@ print_environment() {
     # does not rely on bash.
     for var in WERROR_CFLAGS MAKEFLAGS BUILD \
             ECMULTWINDOW ECMULTGENPRECISION ASM WIDEMUL WITH_VALGRIND EXTRAFLAGS \
-            EXPERIMENTAL ECDH RECOVERY SCHNORRSIG ELLSWIFT \
+            EXPERIMENTAL ECDH RECOVERY SCHNORRSIG SCHNORRSIG_HALFAGG ELLSWIFT \
             ECDSA_S2C GENERATOR RANGEPROOF WHITELIST MUSIG ECDSAADAPTOR BPPP \
             SECP256K1_TEST_ITERS BENCH SECP256K1_BENCH_ITERS CTIMETESTS\
             EXAMPLES \
@@ -82,6 +82,7 @@ esac
     --enable-module-rangeproof="$RANGEPROOF" --enable-module-whitelist="$WHITELIST" --enable-module-generator="$GENERATOR" \
     --enable-module-schnorrsig="$SCHNORRSIG"  --enable-module-musig="$MUSIG" --enable-module-ecdsa-adaptor="$ECDSAADAPTOR" \
     --enable-module-schnorrsig="$SCHNORRSIG" \
+    --enable-module-schnorrsig-halfagg="$SCHNORRSIG_HALFAGG" \
     --enable-examples="$EXAMPLES" \
     --enable-ctime-tests="$CTIMETESTS" \
     --with-valgrind="$WITH_VALGRIND" \

diff --git a/configure.ac b/configure.ac
@@ -209,6 +209,10 @@ 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_schnorrsig_halfagg,
+    AS_HELP_STRING([--enable-module-schnorrsig-halfagg],[enable schnorrsig half-aggregation module (experimental) [default=no]]), [],
+    [SECP_SET_DEFAULT([enable_module_schnorrsig_halfagg], [no], [yes])])
+
 AC_ARG_ENABLE(module_ellswift,
     AS_HELP_STRING([--enable-module-ellswift],[enable ElligatorSwift module [default=yes]]), [],
     [SECP_SET_DEFAULT([enable_module_ellswift], [yes], [yes])])
@@ -485,6 +489,11 @@ if test x"$enable_module_generator" = x"yes"; then
   SECP_CONFIG_DEFINES="$SECP_CONFIG_DEFINES -DENABLE_MODULE_GENERATOR=1"
 fi
 
+if test x"$enable_module_schnorrsig_halfagg" = x"yes"; then
+  SECP_CONFIG_DEFINES="$SECP_CONFIG_DEFINES -DENABLE_MODULE_SCHNORRSIG_HALFAGG=1"
+  enable_module_schnorrsig=yes
+fi
+
 if test x"$enable_module_schnorrsig" = x"yes"; then
   SECP_CONFIG_DEFINES="$SECP_CONFIG_DEFINES -DENABLE_MODULE_SCHNORRSIG=1"
   enable_module_extrakeys=yes
@@ -548,6 +557,9 @@ else
   if test x"$enable_module_musig" = x"yes"; then
     AC_MSG_ERROR([MuSig module is experimental. Use --enable-experimental to allow.])
   fi
+  if test x"$enable_module_schnorrsig_halfagg" = x"yes"; then
+    AC_MSG_ERROR([Schnorrsig Half-Aggregation module is experimental. Use --enable-experimental to allow.])
+  fi
   if test x"$enable_module_ecdsa_s2c" = x"yes"; then
     AC_MSG_ERROR([ECDSA sign-to-contract module module is experimental. Use --enable-experimental to allow.])
   fi
@@ -581,6 +593,7 @@ AM_CONDITIONAL([ENABLE_MODULE_RANGEPROOF], [test x"$enable_module_rangeproof" =
 AM_CONDITIONAL([ENABLE_MODULE_WHITELIST], [test x"$enable_module_whitelist" = x"yes"])
 AM_CONDITIONAL([ENABLE_MODULE_EXTRAKEYS], [test x"$enable_module_extrakeys" = x"yes"])
 AM_CONDITIONAL([ENABLE_MODULE_SCHNORRSIG], [test x"$enable_module_schnorrsig" = x"yes"])
+AM_CONDITIONAL([ENABLE_MODULE_SCHNORRSIG_HALFAGG], [test x"$enable_module_schnorrsig_halfagg" = x"yes"])
 AM_CONDITIONAL([ENABLE_MODULE_ELLSWIFT], [test x"$enable_module_ellswift" = x"yes"])
 AM_CONDITIONAL([ENABLE_MODULE_ECDSA_S2C], [test x"$enable_module_ecdsa_s2c" = x"yes"])
 AM_CONDITIONAL([ENABLE_MODULE_ECDSA_ADAPTOR], [test x"$enable_module_ecdsa_adaptor" = x"yes"])
@@ -597,37 +610,38 @@ AC_OUTPUT
 
 echo
 echo "Build Options:"
-echo "  with external callbacks = $enable_external_default_callbacks"
-echo "  with benchmarks         = $enable_benchmark"
-echo "  with tests              = $enable_tests"
-echo "  with ctime tests        = $enable_ctime_tests"
-echo "  with coverage           = $enable_coverage"
-echo "  with examples           = $enable_examples"
-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 "  module generator        = $enable_module_generator"
-echo "  module rangeproof       = $enable_module_rangeproof"
-echo "  module surjectionproof  = $enable_module_surjectionproof"
-echo "  module whitelist        = $enable_module_whitelist"
-echo "  module musig            = $enable_module_musig"
-echo "  module ecdsa-s2c        = $enable_module_ecdsa_s2c"
-echo "  module ecdsa-adaptor    = $enable_module_ecdsa_adaptor"
-echo "  module bppp             = $enable_module_bppp"
+echo "  with external callbacks   = $enable_external_default_callbacks"
+echo "  with benchmarks           = $enable_benchmark"
+echo "  with tests                = $enable_tests"
+echo "  with ctime tests          = $enable_ctime_tests"
+echo "  with coverage             = $enable_coverage"
+echo "  with examples             = $enable_examples"
+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 schnorrsig-halfagg = $enable_module_schnorrsig_halfagg"
+echo "  module ellswift           = $enable_module_ellswift"
+echo "  module generator          = $enable_module_generator"
+echo "  module rangeproof         = $enable_module_rangeproof"
+echo "  module surjectionproof    = $enable_module_surjectionproof"
+echo "  module whitelist          = $enable_module_whitelist"
+echo "  module musig              = $enable_module_musig"
+echo "  module ecdsa-s2c          = $enable_module_ecdsa_s2c"
+echo "  module ecdsa-adaptor      = $enable_module_ecdsa_adaptor"
+echo "  module bppp               = $enable_module_bppp"
 echo
-echo "  asm                     = $set_asm"
-echo "  ecmult window size      = $set_ecmult_window"
-echo "  ecmult gen prec. bits   = $set_ecmult_gen_precision"
+echo "  asm                       = $set_asm"
+echo "  ecmult window size        = $set_ecmult_window"
+echo "  ecmult gen prec. bits     = $set_ecmult_gen_precision"
 # Hide test-only options unless they're used.
 if test x"$set_widemul" != xauto; then
-echo "  wide multiplication     = $set_widemul"
+echo "  wide multiplication       = $set_widemul"
 fi
 echo
-echo "  valgrind                = $enable_valgrind"
-echo "  CC                      = $CC"
-echo "  CPPFLAGS                = $CPPFLAGS"
-echo "  SECP_CFLAGS             = $SECP_CFLAGS"
-echo "  CFLAGS                  = $CFLAGS"
-echo "  LDFLAGS                 = $LDFLAGS"
+echo "  valgrind                  = $enable_valgrind"
+echo "  CC                        = $CC"
+echo "  CPPFLAGS                  = $CPPFLAGS"
+echo "  SECP_CFLAGS               = $SECP_CFLAGS"
+echo "  CFLAGS                    = $CFLAGS"
+echo "  LDFLAGS                   = $LDFLAGS"