Merge bitcoin/bitcoin#26691: Update secp256k1 subtree to libsecp256k1 version 0.2.0

202291722300b86f36e97de7960d40a32544c2d1 Add secp256k1_selftest call (Pieter Wuille)
3bfca788b0dae879bfc745cc52c2cb6edc49fd70 Remove explicit enabling of default modules (Pieter Wuille)
4462cb04986d77eddcfc6e8f75e04dc278a8147a Adapt to libsecp256k1 API changes (Pieter Wuille)
9d47e7b71b2805430e8c7b43816efd225a6ccd8c Squashed 'src/secp256k1/' changes from 44c2452fd3..21ffe4b22a (Pieter Wuille)

Pull request description:

  Now that libsecp256k1 has a release (https://lists.linuxfoundation.org/pipermail/bitcoin-dev/2022-December/021271.html), update the subtree to match it.

  The changes themselves are not very impactful for Bitcoin Core, but include:
  * It's no longer needed to specify whether contexts are for signing or verification or both (all contexts support everything), so make use of that in this PR.
  * Verification operations can use the static context now, removing the need for some infrastructure in pubkey.cpp to make sure a context exists.
  * Most modules are now enabled by default, so we can drop explicit enabling for them.
  * CI improvements (in particular, MSVC and more recent MacOS)
  * Introduction of an internal int128 type, which has no effect for GCC/Clang builds, but enables 128-bit multiplication in MSVC, giving a ~20% speedup there (but still slower than GCC/Clang).
  * Release process changes (process documentation, changelog, ...).

ACKs for top commit:
  Sjors:
    ACK 202291722300b86f36e97de7960d40a32544c2d1, but 4462cb04986d77eddcfc6e8f75e04dc278a8147a could use more eyes on it.
  achow101:
    ACK 202291722300b86f36e97de7960d40a32544c2d1
  jonasnick:
    utACK 202291722300b86f36e97de7960d40a32544c2d1

Tree-SHA512: 8a9fe28852abe74abd6f96fef16a94d5a427b1d99bff4caab1699014d24698aab9b966a5364a46ed1001c07a7c1d825154ed4e6557c7decce952b77330a8616b

1 files changed, 7 insertions, 7 deletions

diff --git a/src/key.cpp b/src/key.cpp
index 0cb51cb9be..33913ed461 100644
--- a/src/key.cpp
+++ b/src/key.cpp
@@ -233,7 +233,7 @@ bool CKey::Sign(const uint256 &hash, std::vector<unsigned char>& vchSig, bool gr
     secp256k1_pubkey pk;
     ret = secp256k1_ec_pubkey_create(secp256k1_context_sign, &pk, begin());
     assert(ret);
-    ret = secp256k1_ecdsa_verify(GetVerifyContext(), &sig, hash.begin(), &pk);
+    ret = secp256k1_ecdsa_verify(secp256k1_context_static, &sig, hash.begin(), &pk);
     assert(ret);
     return true;
 }
@@ -268,9 +268,9 @@ bool CKey::SignCompact(const uint256 &hash, std::vector<unsigned char>& vchSig)
     secp256k1_pubkey epk, rpk;
     ret = secp256k1_ec_pubkey_create(secp256k1_context_sign, &epk, begin());
     assert(ret);
-    ret = secp256k1_ecdsa_recover(GetVerifyContext(), &rpk, &rsig, hash.begin());
+    ret = secp256k1_ecdsa_recover(secp256k1_context_static, &rpk, &rsig, hash.begin());
     assert(ret);
-    ret = secp256k1_ec_pubkey_cmp(GetVerifyContext(), &epk, &rpk);
+    ret = secp256k1_ec_pubkey_cmp(secp256k1_context_static, &epk, &rpk);
     assert(ret == 0);
     return true;
 }
@@ -286,14 +286,14 @@ bool CKey::SignSchnorr(const uint256& hash, Span<unsigned char> sig, const uint2
         unsigned char pubkey_bytes[32];
         if (!secp256k1_xonly_pubkey_serialize(secp256k1_context_sign, pubkey_bytes, &pubkey)) return false;
         uint256 tweak = XOnlyPubKey(pubkey_bytes).ComputeTapTweakHash(merkle_root->IsNull() ? nullptr : merkle_root);
-        if (!secp256k1_keypair_xonly_tweak_add(GetVerifyContext(), &keypair, tweak.data())) return false;
+        if (!secp256k1_keypair_xonly_tweak_add(secp256k1_context_static, &keypair, tweak.data())) return false;
     }
     bool ret = secp256k1_schnorrsig_sign32(secp256k1_context_sign, sig.data(), hash.data(), &keypair, aux.data());
     if (ret) {
         // Additional verification step to prevent using a potentially corrupted signature
         secp256k1_xonly_pubkey pubkey_verify;
-        ret = secp256k1_keypair_xonly_pub(GetVerifyContext(), &pubkey_verify, nullptr, &keypair);
-        ret &= secp256k1_schnorrsig_verify(GetVerifyContext(), sig.data(), hash.begin(), 32, &pubkey_verify);
+        ret = secp256k1_keypair_xonly_pub(secp256k1_context_static, &pubkey_verify, nullptr, &keypair);
+        ret &= secp256k1_schnorrsig_verify(secp256k1_context_static, sig.data(), hash.begin(), 32, &pubkey_verify);
     }
     if (!ret) memory_cleanse(sig.data(), sig.size());
     memory_cleanse(&keypair, sizeof(keypair));
@@ -392,7 +392,7 @@ bool ECC_InitSanityCheck() {
 void ECC_Start() {
     assert(secp256k1_context_sign == nullptr);
 
-    secp256k1_context *ctx = secp256k1_context_create(SECP256K1_CONTEXT_SIGN);
+    secp256k1_context *ctx = secp256k1_context_create(SECP256K1_CONTEXT_NONE);
     assert(ctx != nullptr);
 
     {