int _goboringcrypto_ECDSA_sign(int, const uint8_t*, size_t, uint8_t*, unsigned int*, const GO_EC_KEY*);
size_t _goboringcrypto_ECDSA_size(const GO_EC_KEY*);
int _goboringcrypto_ECDSA_verify(int, const uint8_t*, size_t, const uint8_t*, size_t, const GO_EC_KEY*);

// #include <openssl/rsa.h>

// Note: order of struct fields here is unchecked.