diff options
Diffstat (limited to 'src/secp256k1/include/secp256k1.h')
-rw-r--r-- | src/secp256k1/include/secp256k1.h | 61 |
1 files changed, 34 insertions, 27 deletions
diff --git a/src/secp256k1/include/secp256k1.h b/src/secp256k1/include/secp256k1.h index 826ab75850..325f35eb04 100644 --- a/src/secp256k1/include/secp256k1.h +++ b/src/secp256k1/include/secp256k1.h @@ -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) @@ -291,8 +298,11 @@ SECP256K1_API secp256k1_context* secp256k1_context_create( * called at most once for every call of this function. If you need to avoid dynamic * memory allocation entirely, see the functions in secp256k1_preallocated.h. * + * Cloning secp256k1_context_static is not possible, and should not be emulated by + * the caller (e.g., using memcpy). Create a new context instead. + * * Returns: a newly created context object. - * Args: ctx: an existing context to copy + * Args: ctx: an existing context to copy (not secp256k1_context_static) */ SECP256K1_API secp256k1_context* secp256k1_context_clone( const secp256k1_context* ctx @@ -310,6 +320,7 @@ SECP256K1_API secp256k1_context* secp256k1_context_clone( * * Args: ctx: an existing context to destroy, constructed using * secp256k1_context_create or secp256k1_context_clone + * (i.e., not secp256k1_context_static). */ SECP256K1_API void secp256k1_context_destroy( secp256k1_context* ctx @@ -627,10 +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. * @@ -820,10 +831,10 @@ SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_pubkey_tweak_mul( /** Randomizes the context to provide enhanced protection against side-channel leakage. * - * Returns: 1: randomization successful (or called on copy of secp256k1_context_static) + * Returns: 1: randomization successful * 0: error - * Args: ctx: pointer to a context object. - * In: seed32: pointer to a 32-byte random seed (NULL resets to initial state) + * Args: ctx: pointer to a context object (not secp256k1_context_static). + * In: seed32: pointer to a 32-byte random seed (NULL resets to initial state). * * While secp256k1 code is written and tested to be constant-time no matter what * secret values are, it is possible that a compiler may output code which is not, @@ -838,21 +849,17 @@ SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_pubkey_tweak_mul( * functions that perform computations involving secret keys, e.g., signing and * public key generation. It is possible to call this function more than once on * the same context, and doing so before every few computations involving secret - * keys is recommended as a defense-in-depth measure. + * keys is recommended as a defense-in-depth measure. Randomization of the static + * context secp256k1_context_static is not supported. * * Currently, the random seed is mainly used for blinding multiplications of a * secret scalar with the elliptic curve base point. Multiplications of this * kind are performed by exactly those API functions which are documented to - * require a context that is not the secp256k1_context_static. As a rule of thumb, + * require a context that is not secp256k1_context_static. As a rule of thumb, * these are all functions which take a secret key (or a keypair) as an input. * A notable exception to that rule is the ECDH module, which relies on a different * kind of elliptic curve point multiplication and thus does not benefit from * enhanced protection against side-channel leakage currently. - * - * It is safe call this function on a copy of secp256k1_context_static in writable - * memory (e.g., obtained via secp256k1_context_clone). In that case, this - * function is guaranteed to return 1, but the call will have no effect because - * the static context (or a copy thereof) is not meant to be randomized. */ SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_context_randomize( secp256k1_context* ctx, |