Fix warnings building secp256k1 tests with openssl 3.0

[andypost]

Is your feature request related to a problem? Please describe.

Building package 22.0 for Alpinelinux using OpenSSL 3.0 getting warnings that tests using deprecated in 3.0 functions (only tests affected)

log of `make check`

make[4]: Entering directory '/home/skilld/aports/community/bitcoin/src/bitcoin-22.0/src/secp256k1'
  CC       src/exhaustive_tests-tests_exhaustive.o
  CC       src/tests-tests.o
src/tests.c: In function 'get_openssl_key':
src/tests.c:6161:5: warning: 'EC_KEY_new_by_curve_name' is deprecated: Since OpenSSL 3.0 [-Wdeprecated-declarations]
 6161 |     EC_KEY *ec_key = EC_KEY_new_by_curve_name(NID_secp256k1);
      |     ^~~~~~
In file included from src/tests.c:25:
/usr/include/openssl/ec.h:996:31: note: declared here
  996 | OSSL_DEPRECATEDIN_3_0 EC_KEY *EC_KEY_new_by_curve_name(int nid);
      |                               ^~~~~~~~~~~~~~~~~~~~~~~~
src/tests.c:6163:5: warning: 'd2i_ECPrivateKey' is deprecated: Since OpenSSL 3.0 [-Wdeprecated-declarations]
 6163 |     CHECK(d2i_ECPrivateKey(&ec_key, &pbegin, privkeylen));
      |     ^~~~~
In file included from src/tests.c:25:
/usr/include/openssl/ec.h:1185:31: note: declared here
 1185 | OSSL_DEPRECATEDIN_3_0 EC_KEY *d2i_ECPrivateKey(EC_KEY **key,
      |                               ^~~~~~~~~~~~~~~~
src/tests.c:6164:5: warning: 'EC_KEY_check_key' is deprecated: Since OpenSSL 3.0 [-Wdeprecated-declarations]
 6164 |     CHECK(EC_KEY_check_key(ec_key));
      |     ^~~~~
In file included from src/tests.c:25:
/usr/include/openssl/ec.h:1105:27: note: declared here
 1105 | OSSL_DEPRECATEDIN_3_0 int EC_KEY_check_key(const EC_KEY *key);
      |                           ^~~~~~~~~~~~~~~~
src/tests.c: In function 'test_ecdsa_openssl':
src/tests.c:6189:5: warning: 'ECDSA_sign' is deprecated: Since OpenSSL 3.0 [-Wdeprecated-declarations]
 6189 |     CHECK(ECDSA_sign(0, message, sizeof(message), signature, &sigsize, ec_key));
      |     ^~~~~
In file included from src/tests.c:25:
/usr/include/openssl/ec.h:1412:27: note: declared here
 1412 | OSSL_DEPRECATEDIN_3_0 int ECDSA_sign(int type, const unsigned char *dgst,
      |                           ^~~~~~~~~~
src/tests.c:6198:5: warning: 'ECDSA_verify' is deprecated: Since OpenSSL 3.0 [-Wdeprecated-declarations]
 6198 |     CHECK(ECDSA_verify(0, message, sizeof(message), signature, secp_sigsize, ec_key) == 1);
      |     ^~~~~
In file included from src/tests.c:25:
/usr/include/openssl/ec.h:1445:27: note: declared here
 1445 | OSSL_DEPRECATEDIN_3_0 int ECDSA_verify(int type, const unsigned char *dgst,
      |                           ^~~~~~~~~~~~
src/tests.c:6200:5: warning: 'EC_KEY_free' is deprecated: Since OpenSSL 3.0 [-Wdeprecated-declarations]
 6200 |     EC_KEY_free(ec_key);
      |     ^~~~~~~~~~~
In file included from src/tests.c:25:
/usr/include/openssl/ec.h:1001:28: note: declared here
 1001 | OSSL_DEPRECATEDIN_3_0 void EC_KEY_free(EC_KEY *key);
      |                            ^~~~~~~~~~~
  CCLD     exhaustive_tests
  CCLD     tests
make  check-TESTS
make[5]: Entering directory '/home/skilld/aports/community/bitcoin/src/bitcoin-22.0/src/secp256k1'
make[6]: Entering directory '/home/skilld/aports/community/bitcoin/src/bitcoin-22.0/src/secp256k1'
PASS: exhaustive_tests
FAIL: tests
============================================================================
Testsuite summary for libsecp256k1 0.1
============================================================================
# TOTAL: 2
# PASS:  1
# SKIP:  0
# XFAIL: 0
# FAIL:  1
# XPASS: 0
# ERROR: 0

Describe the solution you'd like

According to man it needs replacement

Describe alternatives you've considered

Used to configure with --disable-openssl-tests

Additional context

Alpinelinux started OpenSSL 3.0 adoption

[fanquake]

If you'd like these "fixed" you should open an issue in the upstream secp256k1 repo: https://github.com/bitcoin-core/secp256k1.

[andypost]

Thank you, will do

[hebasto]

Could be closed here?

[fanquake]

Yes. Looks like the OpenSSL related code may even be removed shortly upstream.