Merge bitcoin-core/secp256k1#1209: build: Add SECP256K1_API_VAR to fix importing variables from DLLs

e4330341bd ci: Shutdown wineserver whenever CI script exits (Tim Ruffing)
9a5a611a21 build: Suppress stupid MSVC linker warning (Tim Ruffing)
739c53b19a examples: Extend sig examples by call that uses static context (Tim Ruffing)
914276e4d2 build: Add SECP256K1_API_VAR to fix importing variables from DLLs (Tim Ruffing)

Pull request description:

  ... and more Windows fixes, please see the individual commits.

  The fixed issues were discovered in https://github.com/bitcoin-core/secp256k1/pull/1198.

ACKs for top commit:
  sipa:
    utACK e4330341bd
  hebasto:
    ACK e4330341bd, tested on Windows using [CMake](https://github.com/bitcoin-core/secp256k1/pull/1113) (which means that the 3rd commit is reviewed only, but not tested). FWIW, `LNK4217` warnings have been indeed observed.

Tree-SHA512: ce7845b106190cdc517988c30aaf2cc9f1d6da22904dfc5cb6bf4ee05f063929dc8b3038479e703b6cebac79d1c21d0c84560344d2478cb1c1740087383f40e3
This commit is contained in:
Tim Ruffing 2023-02-22 00:34:01 +01:00
commit cbd2555934
No known key found for this signature in database
GPG Key ID: 8C461CCD293F6011
8 changed files with 55 additions and 26 deletions

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@ -258,7 +258,7 @@ task:
# Set non-essential options that affect the CLI messages here.
# (They depend on the user's taste, so we don't want to set them automatically in configure.ac.)
CFLAGS: -nologo -diagnostics:caret
LDFLAGS: -XCClinker -nologo -XCClinker -diagnostics:caret
LDFLAGS: -Xlinker -Xlinker -Xlinker -nologo
matrix:
- name: "x86_64 (MSVC): Windows (Debian stable, Wine)"
- name: "x86_64 (MSVC): Windows (Debian stable, Wine, int128_struct)"

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@ -34,6 +34,8 @@ print_environment
# This speeds up jobs with many invocations of wine (e.g., ./configure with MSVC) tremendously.
case "$WRAPPER_CMD" in
*wine*)
# Make sure to shutdown wineserver whenever we exit.
trap "wineserver -k || true" EXIT INT HUP
# This is apparently only reliable when we run a dummy command such as "hh.exe" afterwards.
wineserver -p && wine hh.exe
;;
@ -111,9 +113,6 @@ then
make precomp
fi
# Shutdown wineserver again
wineserver -k || true
# Check that no repo files have been modified by the build.
# (This fails for example if the precomp files need to be updated in the repo.)
git diff --exit-code

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@ -115,6 +115,12 @@ AC_DEFUN([SECP_TRY_APPEND_DEFAULT_CFLAGS], [
if test x"$GCC" != x"yes" && test x"$build_windows" = x"yes"; then
SECP_TRY_APPEND_CFLAGS([-W2 -wd4146], $1) # Moderate warning level, disable warning C4146 "unary minus operator applied to unsigned type, result still unsigned"
SECP_TRY_APPEND_CFLAGS([-external:anglebrackets -external:W0], $1) # Suppress warnings from #include <...> files
# We pass -ignore:4217 to the MSVC linker to suppress warning 4217 when
# importing variables from a statically linked secp256k1.
# (See the libtool manual, section "Windows DLLs" for background.)
# Unfortunately, libtool tries to be too clever and strips "-Xlinker arg"
# into "arg", so this will be " -Xlinker -ignore:4217" after stripping.
LDFLAGS="-Xlinker -Xlinker -Xlinker -ignore:4217 $LDFLAGS"
fi
])
SECP_TRY_APPEND_DEFAULT_CFLAGS(SECP_CFLAGS)

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@ -34,7 +34,7 @@ int main(void) {
unsigned char compressed_pubkey[33];
unsigned char serialized_signature[64];
size_t len;
int is_signature_valid;
int is_signature_valid, is_signature_valid2;
int return_val;
secp256k1_pubkey pubkey;
secp256k1_ecdsa_signature sig;
@ -116,10 +116,18 @@ int main(void) {
printf("Signature: ");
print_hex(serialized_signature, sizeof(serialized_signature));
/* This will clear everything from the context and free the memory */
secp256k1_context_destroy(ctx);
/* Bonus example: if all we need is signature verification (and no key
generation or signing), we don't need to use a context created via
secp256k1_context_create(). We can simply use the static (i.e., global)
context secp256k1_context_static. See its description in
include/secp256k1.h for details. */
is_signature_valid2 = secp256k1_ecdsa_verify(secp256k1_context_static,
&sig, msg_hash, &pubkey);
assert(is_signature_valid2 == is_signature_valid);
/* It's best practice to try to clear secrets from memory after using them.
* This is done because some bugs can allow an attacker to leak memory, for
* example through "out of bounds" array access (see Heartbleed), Or the OS

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@ -26,7 +26,7 @@ int main(void) {
unsigned char auxiliary_rand[32];
unsigned char serialized_pubkey[32];
unsigned char signature[64];
int is_signature_valid;
int is_signature_valid, is_signature_valid2;
int return_val;
secp256k1_xonly_pubkey pubkey;
secp256k1_keypair keypair;
@ -135,6 +135,15 @@ int main(void) {
/* This will clear everything from the context and free the memory */
secp256k1_context_destroy(ctx);
/* Bonus example: if all we need is signature verification (and no key
generation or signing), we don't need to use a context created via
secp256k1_context_create(). We can simply use the static (i.e., global)
context secp256k1_context_static. See its description in
include/secp256k1.h for details. */
is_signature_valid2 = secp256k1_schnorrsig_verify(secp256k1_context_static,
signature, msg_hash, 32, &pubkey);
assert(is_signature_valid2 == is_signature_valid);
/* It's best practice to try to clear secrets from memory after using them.
* This is done because some bugs can allow an attacker to leak memory, for
* example through "out of bounds" array access (see Heartbleed), Or the OS

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@ -145,21 +145,28 @@ typedef int (*secp256k1_nonce_function)(
# define SECP256K1_NO_BUILD
#endif
/** At secp256k1 build-time DLL_EXPORT is defined when building objects destined
* for a shared library, but not for those intended for static libraries.
*/
#ifndef SECP256K1_API
# if defined(_WIN32)
# if defined(SECP256K1_BUILD) && defined(DLL_EXPORT)
# define SECP256K1_API __declspec(dllexport)
# else
# define SECP256K1_API
/* Symbol visibility. See libtool manual, section "Windows DLLs". */
#if defined(_WIN32) && !defined(__GNUC__)
# ifdef SECP256K1_BUILD
# ifdef DLL_EXPORT
# define SECP256K1_API __declspec (dllexport)
# define SECP256K1_API_VAR extern __declspec (dllexport)
# endif
# elif defined(__GNUC__) && (__GNUC__ >= 4) && defined(SECP256K1_BUILD)
# define SECP256K1_API __attribute__ ((visibility ("default")))
# elif defined _MSC_VER
# define SECP256K1_API
# define SECP256K1_API_VAR extern __declspec (dllimport)
# elif defined DLL_EXPORT
# define SECP256K1_API __declspec (dllimport)
# define SECP256K1_API_VAR extern __declspec (dllimport)
# endif
#endif
#ifndef SECP256K1_API
# if defined(__GNUC__) && (__GNUC__ >= 4) && defined(SECP256K1_BUILD)
# define SECP256K1_API __attribute__ ((visibility ("default")))
# define SECP256K1_API_VAR extern __attribute__ ((visibility ("default")))
# else
# define SECP256K1_API
# define SECP256K1_API_VAR extern
# endif
#endif
@ -231,10 +238,10 @@ typedef int (*secp256k1_nonce_function)(
*
* It is highly recommended to call secp256k1_selftest before using this context.
*/
SECP256K1_API extern const secp256k1_context *secp256k1_context_static;
SECP256K1_API_VAR const secp256k1_context *secp256k1_context_static;
/** Deprecated alias for secp256k1_context_static. */
SECP256K1_API extern const secp256k1_context *secp256k1_context_no_precomp
SECP256K1_API_VAR const secp256k1_context *secp256k1_context_no_precomp
SECP256K1_DEPRECATED("Use secp256k1_context_static instead");
/** Perform basic self tests (to be used in conjunction with secp256k1_context_static)
@ -631,10 +638,10 @@ SECP256K1_API int secp256k1_ecdsa_signature_normalize(
* If a data pointer is passed, it is assumed to be a pointer to 32 bytes of
* extra entropy.
*/
SECP256K1_API extern const secp256k1_nonce_function secp256k1_nonce_function_rfc6979;
SECP256K1_API_VAR const secp256k1_nonce_function secp256k1_nonce_function_rfc6979;
/** A default safe nonce generation function (currently equal to secp256k1_nonce_function_rfc6979). */
SECP256K1_API extern const secp256k1_nonce_function secp256k1_nonce_function_default;
SECP256K1_API_VAR const secp256k1_nonce_function secp256k1_nonce_function_default;
/** Create an ECDSA signature.
*

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@ -27,11 +27,11 @@ typedef int (*secp256k1_ecdh_hash_function)(
/** An implementation of SHA256 hash function that applies to compressed public key.
* Populates the output parameter with 32 bytes. */
SECP256K1_API extern const secp256k1_ecdh_hash_function secp256k1_ecdh_hash_function_sha256;
SECP256K1_API_VAR const secp256k1_ecdh_hash_function secp256k1_ecdh_hash_function_sha256;
/** A default ECDH hash function (currently equal to secp256k1_ecdh_hash_function_sha256).
* Populates the output parameter with 32 bytes. */
SECP256K1_API extern const secp256k1_ecdh_hash_function secp256k1_ecdh_hash_function_default;
SECP256K1_API_VAR const secp256k1_ecdh_hash_function secp256k1_ecdh_hash_function_default;
/** Compute an EC Diffie-Hellman secret in constant time
*

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@ -61,7 +61,7 @@ typedef int (*secp256k1_nonce_function_hardened)(
* Therefore, to create BIP-340 compliant signatures, algo must be set to
* "BIP0340/nonce" and algolen to 13.
*/
SECP256K1_API extern const secp256k1_nonce_function_hardened secp256k1_nonce_function_bip340;
SECP256K1_API_VAR const secp256k1_nonce_function_hardened secp256k1_nonce_function_bip340;
/** Data structure that contains additional arguments for schnorrsig_sign_custom.
*