Add ecdsa c_bind.

cpp/src/barretenberg/crypto/ecdsa/c_bind.cpp

@@ -0,0 +1,70 @@
+#include "ecdsa.hpp"
+#include <ecc/curves/secp256k1/secp256k1.hpp>
+
+#define WASM_EXPORT __attribute__((visibility("default")))
+
+extern "C" {
+
+WASM_EXPORT void ecdsa__compute_public_key(uint8_t const* private_key, uint8_t* public_key_buf)
+{
+    auto priv_key = from_buffer<secp256k1::fr>(private_key);
+    secp256k1::g1::affine_element pub_key = secp256k1::g1::one * priv_key;
+    write(public_key_buf, pub_key);
+}
+
+WASM_EXPORT void ecdsa__construct_signature(uint8_t const* message,
+                                            size_t msg_len,
+                                            uint8_t const* private_key,
+                                            uint8_t* output_sig_r,
+                                            uint8_t* output_sig_s,
+                                            uint8_t* output_sig_v)
+{
+    using serialize::write;
+    auto priv_key = from_buffer<secp256k1::fr>(private_key);
+    secp256k1::g1::affine_element pub_key = secp256k1::g1::one * priv_key;
+    crypto::ecdsa::key_pair<secp256k1::fr, secp256k1::g1> key_pair = { priv_key, pub_key };
+
+    auto sig = crypto::ecdsa::construct_signature<Sha256Hasher, secp256k1::fq, secp256k1::fr, secp256k1::g1>(
+        std::string((char*)message, msg_len), key_pair);
+    write(output_sig_r, sig.r);
+    write(output_sig_s, sig.s);
+    write(output_sig_v, sig.v);
+}
+
+WASM_EXPORT void ecdsa__recover_public_key_from_signature(uint8_t const* message,
+                                                          size_t msg_len,
+                                                          uint8_t const* sig_r,
+                                                          uint8_t const* sig_s,
+                                                          uint8_t* sig_v,
+                                                          uint8_t* output_pub_key)
+{
+    std::array<uint8_t, 32> r, s;
+    std::copy(sig_r, sig_r + 32, r.begin());
+    std::copy(sig_s, sig_s + 32, s.begin());
+    const uint8_t v = *sig_v;
+
+    crypto::ecdsa::signature sig = { r, s, v };
+    auto recovered_pub_key =
+        crypto::ecdsa::recover_public_key<Sha256Hasher, secp256k1::fq, secp256k1::fr, secp256k1::g1>(
+            std::string((char*)message, msg_len), sig);
+    write(output_pub_key, recovered_pub_key);
+}
+
+WASM_EXPORT bool ecdsa__verify_signature(uint8_t const* message,
+                                         size_t msg_len,
+                                         uint8_t const* pub_key,
+                                         uint8_t const* sig_r,
+                                         uint8_t const* sig_s,
+                                         uint8_t const* sig_v)
+{
+    auto pubk = from_buffer<secp256k1::g1::affine_element>(pub_key);
+    std::array<uint8_t, 32> r, s;
+    std::copy(sig_r, sig_r + 32, r.begin());
+    std::copy(sig_s, sig_s + 32, s.begin());
+    const uint8_t v = *sig_v;
+
+    crypto::ecdsa::signature sig = { r, s, v };
+    return crypto::ecdsa::verify_signature<Sha256Hasher, secp256k1::fq, secp256k1::fr, secp256k1::g1>(
+        std::string((char*)message, msg_len), pubk, sig);
+}
+}