Partial merge bitcoin#22448: Update libsecp256k1 subtree to latest upstream

c020cba Squashed 'src/secp256k1/' changes from efad350..be8d9c2 (Pieter Wuille)

Pull request description:

  This updates our src/secp256k1 subtree to the lastest upstream master. Notable changes:
  * New schnorrsig API (bitcoin-core/secp256k1#844), which adds support for variable-length messages (not used in BIP341/342 transaction signing, so not relevant for us, but it changes the API, and makes some other simplifications). Some of our call sites had to be adapted.
  * Don't use asm optimizations for `gen_context` (bitcoin-core/secp256k1#965). This fixes bitcoin#22441.
  * Various testing/CI improvements

ACKs for top commit:
  hebasto:
    ACK e4ffb44
  jonatack:
    Light ACK e4ffb44 debug built (debian clang 13.0), ran bitcoind node/tests/git-subtree-check.sh, lightly reviewed the diff and API changes
  fanquake:
    ACK e4ffb44

Tree-SHA512: 89a5c3019ec010d578e84bcef756d2c679420c5c768bcdece673405c4e10955179c5a1339aafc68b8b74b1e3912e147bf2f392f44f15af73791d93f6537960b3

Author: fanquake

src/secp256k1/.cirrus.yml

@@ -1,21 +1,28 @@
 env:
-  WIDEMUL: auto
+  ### compiler options
+  HOST:
+  # Specific warnings can be disabled with -Wno-error=foo.
+  # -pedantic-errors is not equivalent to -Werror=pedantic and thus not implied by -Werror according to the GCC manual.
+  WERROR_CFLAGS: -Werror -pedantic-errors
+  MAKEFLAGS: -j2
+  BUILD: check
+  ### secp256k1 config
   STATICPRECOMPUTATION: yes
   ECMULTGENPRECISION: auto
   ASM: no
-  BUILD: check
+  WIDEMUL: auto
   WITH_VALGRIND: yes
-  RUN_VALGRIND: no
   EXTRAFLAGS:
-  HOST:
+  ### secp256k1 modules
+  EXPERIMENTAL: no
   ECDH: no
   RECOVERY: no
   SCHNORRSIG: no
-  EXPERIMENTAL: no
-  CTIMETEST: yes
+  ### test options
+  TEST_ITERS:
   BENCH: yes
-  ITERS: 2
-  MAKEFLAGS: -j2
+  BENCH_ITERS: 2
+  CTIMETEST: yes
 
 cat_logs_snippet: &CAT_LOGS
   always:
@@ -63,27 +70,8 @@ task:
     - env: {BUILD: distcheck, WITH_VALGRIND: no, CTIMETEST: no, BENCH: no}
     - env: {CPPFLAGS: -DDETERMINISTIC}
     - env: {CFLAGS: -O0, CTIMETEST: no}
-    - env:
-        CFLAGS:  "-fsanitize=undefined -fno-omit-frame-pointer"
-        LDFLAGS: "-fsanitize=undefined -fno-omit-frame-pointer"
-        UBSAN_OPTIONS: "print_stacktrace=1:halt_on_error=1"
-        ASM: x86_64
-        ECDH: yes
-        RECOVERY: yes
-        EXPERIMENTAL: yes
-        SCHNORRSIG: yes
-        CTIMETEST: no
     - env: { ECMULTGENPRECISION: 2 }
     - env: { ECMULTGENPRECISION: 8 }
-    - env:
-        RUN_VALGRIND: yes
-        ASM: x86_64
-        ECDH: yes
-        RECOVERY: yes
-        EXPERIMENTAL: yes
-        SCHNORRSIG: yes
-        EXTRAFLAGS: "--disable-openssl-tests"
-        BUILD:
   matrix:
     - env:
         CC: gcc
@@ -111,6 +99,7 @@ task:
         CC: i686-linux-gnu-gcc
     - env:
         CC: clang --target=i686-pc-linux-gnu -isystem /usr/i686-linux-gnu/include
+  << : *MERGE_BASE
   test_script:
     - ./ci/cirrus.sh
   << : *CAT_LOGS
@@ -181,9 +170,9 @@ task:
     cpu: 1
     memory: 1G
   env:
-    QEMU_CMD: qemu-s390x
+    WRAPPER_CMD: qemu-s390x
+    TEST_ITERS: 16
     HOST: s390x-linux-gnu
-    BUILD:
     WITH_VALGRIND: no
     ECDH: yes
     RECOVERY: yes
@@ -196,3 +185,158 @@ task:
     - rm /etc/ld.so.cache
     - ./ci/cirrus.sh
   << : *CAT_LOGS
+
+task:
+  name: "ARM32: Linux (Debian stable, QEMU)"
+  container:
+    dockerfile: ci/linux-debian.Dockerfile
+    cpu: 1
+    memory: 1G
+  env:
+    WRAPPER_CMD: qemu-arm
+    TEST_ITERS: 16
+    HOST: arm-linux-gnueabihf
+    WITH_VALGRIND: no
+    ECDH: yes
+    RECOVERY: yes
+    EXPERIMENTAL: yes
+    SCHNORRSIG: yes
+    CTIMETEST: no
+  matrix:
+    - env: {}
+    - env: {ASM: arm}
+  << : *MERGE_BASE
+  test_script:
+    - ./ci/cirrus.sh
+  << : *CAT_LOGS
+
+task:
+  name: "ARM64: Linux (Debian stable, QEMU)"
+  container:
+    dockerfile: ci/linux-debian.Dockerfile
+    cpu: 1
+    memory: 1G
+  env:
+    WRAPPER_CMD: qemu-aarch64
+    TEST_ITERS: 16
+    HOST: aarch64-linux-gnu
+    WITH_VALGRIND: no
+    ECDH: yes
+    RECOVERY: yes
+    EXPERIMENTAL: yes
+    SCHNORRSIG: yes
+    CTIMETEST: no
+  << : *MERGE_BASE
+  test_script:
+    - ./ci/cirrus.sh
+  << : *CAT_LOGS
+
+task:
+  name: "ppc64le: Linux (Debian stable, QEMU)"
+  container:
+    dockerfile: ci/linux-debian.Dockerfile
+    cpu: 1
+    memory: 1G
+  env:
+    WRAPPER_CMD: qemu-ppc64le
+    TEST_ITERS: 16
+    HOST: powerpc64le-linux-gnu
+    WITH_VALGRIND: no
+    ECDH: yes
+    RECOVERY: yes
+    EXPERIMENTAL: yes
+    SCHNORRSIG: yes
+    CTIMETEST: no
+  << : *MERGE_BASE
+  test_script:
+    - ./ci/cirrus.sh
+  << : *CAT_LOGS
+
+task:
+  name: "x86_64 (mingw32-w64): Windows (Debian stable, Wine)"
+  container:
+    dockerfile: ci/linux-debian.Dockerfile
+    cpu: 1
+    memory: 1G
+  env:
+    WRAPPER_CMD: wine64-stable
+    TEST_ITERS: 16
+    HOST: x86_64-w64-mingw32
+    WITH_VALGRIND: no
+    ECDH: yes
+    RECOVERY: yes
+    EXPERIMENTAL: yes
+    SCHNORRSIG: yes
+    CTIMETEST: no
+  << : *MERGE_BASE
+  test_script:
+    - ./ci/cirrus.sh
+  << : *CAT_LOGS
+
+# Sanitizers
+task:
+  container:
+    dockerfile: ci/linux-debian.Dockerfile
+    cpu: 1
+    memory: 1G
+  env:
+    ECDH: yes
+    RECOVERY: yes
+    EXPERIMENTAL: yes
+    SCHNORRSIG: yes
+    CTIMETEST: no
+    EXTRAFLAGS: "--disable-openssl-tests"
+  matrix:
+    - name: "Valgrind (memcheck)"
+      env:
+        # The `--error-exitcode` is required to make the test fail if valgrind found errors, otherwise it'll return 0 (https://www.valgrind.org/docs/manual/manual-core.html)
+        WRAPPER_CMD: "valgrind --error-exitcode=42"
+        TEST_ITERS: 16
+    - name: "UBSan, ASan, LSan"
+      env:
+        CFLAGS: "-fsanitize=undefined,address"
+        CFLAGS_FOR_BUILD: "-fsanitize=undefined,address"
+        UBSAN_OPTIONS: "print_stacktrace=1:halt_on_error=1"
+        ASAN_OPTIONS: "strict_string_checks=1:detect_stack_use_after_return=1:detect_leaks=1"
+        LSAN_OPTIONS: "use_unaligned=1"
+        TEST_ITERS: 32
+  # Try to cover many configurations with just a tiny matrix.
+  matrix:
+    - env:
+        ASM: auto
+        STATICPRECOMPUTATION: yes
+    - env:
+        ASM: no
+        STATICPRECOMPUTATION: no
+        ECMULTGENPRECISION: 2
+  matrix:
+    - env:
+        CC: clang
+    - env:
+        HOST: i686-linux-gnu
+        CC: i686-linux-gnu-gcc
+  << : *MERGE_BASE
+  test_script:
+    - ./ci/cirrus.sh
+  << : *CAT_LOGS
+
+task:
+  name: "C++ -fpermissive"
+  container:
+    dockerfile: ci/linux-debian.Dockerfile
+    cpu: 1
+    memory: 1G
+  env:
+    # ./configure correctly errors out when given CC=g++.
+    # We hack around this by passing CC=g++ only to make.
+    CC: gcc
+    MAKEFLAGS: -j2 CC=g++ CFLAGS=-fpermissive
+    WERROR_CFLAGS:
+    EXPERIMENTAL: yes
+    ECDH: yes
+    RECOVERY: yes
+    SCHNORRSIG: yes
+  << : *MERGE_BASE
+  test_script:
+    - ./ci/cirrus.sh
+  << : *CAT_LOGS

src/secp256k1/.gitignore

@@ -23,6 +23,7 @@ aclocal.m4
 autom4te.cache/
 config.log
 config.status
+conftest*
 *.tar.gz
 *.la
 libtool
@@ -33,6 +34,14 @@ libtool
 *~
 *.log
 *.trs
+
+coverage/
+coverage.html
+coverage.*.html
+*.gcda
+*.gcno
+*.gcov
+
 src/libsecp256k1-config.h
 src/libsecp256k1-config.h.in
 src/ecmult_static_context.h

src/secp256k1/Makefile.am

@@ -1,5 +1,9 @@
 ACLOCAL_AMFLAGS = -I build-aux/m4
 
+# AM_CFLAGS will be automatically prepended to CFLAGS by Automake when compiling some foo
+# which does not have an explicit foo_CFLAGS variable set.
+AM_CFLAGS = $(SECP_CFLAGS)
+
 lib_LTLIBRARIES = libsecp256k1.la
 include_HEADERS = include/secp256k1.h
 include_HEADERS += include/secp256k1_preallocated.h
@@ -68,7 +72,7 @@ endif
 endif
 
 libsecp256k1_la_SOURCES = src/secp256k1.c
-libsecp256k1_la_CPPFLAGS = -DSECP256K1_BUILD -I$(top_srcdir)/include -I$(top_srcdir)/src $(SECP_INCLUDES)
+libsecp256k1_la_CPPFLAGS = -I$(top_srcdir)/include -I$(top_srcdir)/src $(SECP_INCLUDES)
 libsecp256k1_la_LIBADD = $(SECP_LIBS) $(COMMON_LIB)
 
 if VALGRIND_ENABLED
@@ -81,27 +85,27 @@ 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)
 # SECP_TEST_INCLUDES are only used here for CRYPTO_CPPFLAGS
-bench_verify_CPPFLAGS = -DSECP256K1_BUILD $(SECP_TEST_INCLUDES)
+bench_verify_CPPFLAGS = $(SECP_TEST_INCLUDES)
 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_internal_CPPFLAGS = $(SECP_INCLUDES)
 bench_ecmult_SOURCES = src/bench_ecmult.c
 bench_ecmult_LDADD = $(SECP_LIBS) $(COMMON_LIB)
-bench_ecmult_CPPFLAGS = -DSECP256K1_BUILD $(SECP_INCLUDES)
+bench_ecmult_CPPFLAGS = $(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) $(SECP_TEST_INCLUDES)
+tests_CPPFLAGS = -I$(top_srcdir)/src -I$(top_srcdir)/include $(SECP_INCLUDES) $(SECP_TEST_INCLUDES)
 if VALGRIND_ENABLED
 tests_CPPFLAGS += -DVALGRIND
 noinst_PROGRAMS += valgrind_ctime_test
 valgrind_ctime_test_SOURCES = src/valgrind_ctime_test.c
-valgrind_ctime_test_LDADD = libsecp256k1.la $(SECP_LIBS) $(SECP_LIBS) $(COMMON_LIB)
+valgrind_ctime_test_LDADD = libsecp256k1.la $(SECP_LIBS) $(COMMON_LIB)
 endif
 if !ENABLE_COVERAGE
 tests_CPPFLAGS += -DVERIFY
@@ -114,7 +118,7 @@ endif
 if USE_EXHAUSTIVE_TESTS
 noinst_PROGRAMS += exhaustive_tests
 exhaustive_tests_SOURCES = src/tests_exhaustive.c
-exhaustive_tests_CPPFLAGS = -DSECP256K1_BUILD -I$(top_srcdir)/src $(SECP_INCLUDES)
+exhaustive_tests_CPPFLAGS = -I$(top_srcdir)/src $(SECP_INCLUDES)
 if !ENABLE_COVERAGE
 exhaustive_tests_CPPFLAGS += -DVERIFY
 endif
@@ -129,10 +133,10 @@ CPPFLAGS_FOR_BUILD +=-I$(top_srcdir) -I$(builddir)/src
 gen_context_OBJECTS = gen_context.o
 gen_context_BIN = gen_context$(BUILD_EXEEXT)
 gen_%.o: src/gen_%.c src/libsecp256k1-config.h
-	$(CC_FOR_BUILD) $(CPPFLAGS_FOR_BUILD) $(CFLAGS_FOR_BUILD) -c $< -o $@
+	$(CC_FOR_BUILD) $(DEFS) $(CPPFLAGS_FOR_BUILD) $(SECP_CFLAGS_FOR_BUILD) $(CFLAGS_FOR_BUILD) -c $< -o $@
 
 $(gen_context_BIN): $(gen_context_OBJECTS)
-	$(CC_FOR_BUILD) $(CFLAGS_FOR_BUILD) $(LDFLAGS_FOR_BUILD) $^ -o $@
+	$(CC_FOR_BUILD) $(SECP_CFLAGS_FOR_BUILD) $(CFLAGS_FOR_BUILD) $(LDFLAGS_FOR_BUILD) $^ -o $@
 
 $(libsecp256k1_la_OBJECTS): src/ecmult_static_context.h
 $(tests_OBJECTS): src/ecmult_static_context.h

src/secp256k1/README.md

@@ -17,6 +17,7 @@ Features:
 * Suitable for embedded systems.
 * Optional module for public key recovery.
 * Optional module for ECDH key exchange.
+* Optional module for Schnorr signatures according to [BIP-340](https://github.com/bitcoin/bips/blob/master/bip-0340.mediawiki) (experimental).
 
 Experimental features have not received enough scrutiny to satisfy the standard of quality of this library but are made available for testing and review by the community. The APIs of these features should not be considered stable.
 
@@ -96,7 +97,8 @@ To create a report, `gcovr` is recommended, as it includes branch coverage repor
 
 To create a HTML report with coloured and annotated source code:
 
-    $ gcovr --exclude 'src/bench*' --html --html-details -o coverage.html
+    $ mkdir -p coverage
+    $ gcovr --exclude 'src/bench*' --html --html-details -o coverage/coverage.html
 
 Reporting a vulnerability
 ------------

src/secp256k1/build-aux/m4/bitcoin_secp.m4

@@ -82,3 +82,19 @@ if test x"$has_valgrind" != x"yes"; then
   AC_CHECK_HEADER([valgrind/memcheck.h], [has_valgrind=yes; AC_DEFINE(HAVE_VALGRIND,1,[Define this symbol if valgrind is installed])])
 fi
 ])
+
+dnl SECP_TRY_APPEND_CFLAGS(flags, VAR)
+dnl Append flags to VAR if CC accepts them.
+AC_DEFUN([SECP_TRY_APPEND_CFLAGS], [
+  AC_MSG_CHECKING([if ${CC} supports $1])
+  SECP_TRY_APPEND_CFLAGS_saved_CFLAGS="$CFLAGS"
+  CFLAGS="$1 $CFLAGS"
+  AC_COMPILE_IFELSE([AC_LANG_SOURCE([[char foo;]])], [flag_works=yes], [flag_works=no])
+  AC_MSG_RESULT($flag_works)
+  CFLAGS="$SECP_TRY_APPEND_CFLAGS_saved_CFLAGS"
+  if test x"$flag_works" = x"yes"; then
+    $2="$$2 $1"
+  fi
+  unset flag_works
+  AC_SUBST($2)
+])