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-rw-r--r--include/secp256k1.h150
1 files changed, 101 insertions, 49 deletions
diff --git a/include/secp256k1.h b/include/secp256k1.h
index a6e39d13db..06afd4c65b 100644
--- a/include/secp256k1.h
+++ b/include/secp256k1.h
@@ -40,42 +40,60 @@ extern "C" {
# define SECP256K1_ARG_NONNULL(_x)
# endif
+/** Opaque data structure that holds context information (precomputed tables etc.).
+ * Only functions that take a pointer to a non-const context require exclusive
+ * access to it. Multiple functions that take a pointer to a const context may
+ * run simultaneously.
+ */
+typedef struct secp256k1_context_struct secp256k1_context_t;
+
+/** Flags to pass to secp256k1_context_create. */
+# define SECP256K1_CONTEXT_VERIFY (1 << 0)
+# define SECP256K1_CONTEXT_SIGN (1 << 1)
-/** Flags to pass to secp256k1_start. */
-# define SECP256K1_START_VERIFY (1 << 0)
-# define SECP256K1_START_SIGN (1 << 1)
+/** Create a secp256k1 context object.
+ * Returns: a newly created context object.
+ * In: flags: which parts of the context to initialize.
+ */
+secp256k1_context_t* secp256k1_context_create(
+ int flags
+) SECP256K1_WARN_UNUSED_RESULT;
-/** Initialize the library. This may take some time (10-100 ms).
- * You need to call this before calling any other function.
- * It cannot run in parallel with any other functions, but once
- * secp256k1_start() returns, all other functions are thread-safe.
+/** Copies a secp256k1 context object.
+ * Returns: a newly created context object.
+ * In: ctx: an existing context to copy
*/
-void secp256k1_start(unsigned int flags);
+secp256k1_context_t* secp256k1_context_clone(
+ const secp256k1_context_t* ctx
+) SECP256K1_WARN_UNUSED_RESULT;
-/** Free all memory associated with this library. After this, no
- * functions can be called anymore, except secp256k1_start()
+/** Destroy a secp256k1 context object.
+ * The context pointer may not be used afterwards.
*/
-void secp256k1_stop(void);
+void secp256k1_context_destroy(
+ secp256k1_context_t* ctx
+) SECP256K1_ARG_NONNULL(1);
/** Verify an ECDSA signature.
* Returns: 1: correct signature
* 0: incorrect signature
* -1: invalid public key
* -2: invalid signature
- * In: msg32: the 32-byte message hash being verified (cannot be NULL)
+ * In: ctx: a secp256k1 context object, initialized for verification.
+ * msg32: the 32-byte message hash being verified (cannot be NULL)
* sig: the signature being verified (cannot be NULL)
* siglen: the length of the signature
* pubkey: the public key to verify with (cannot be NULL)
* pubkeylen: the length of pubkey
- * Requires starting using SECP256K1_START_VERIFY.
*/
SECP256K1_WARN_UNUSED_RESULT int secp256k1_ecdsa_verify(
+ const secp256k1_context_t* ctx,
const unsigned char *msg32,
const unsigned char *sig,
int siglen,
const unsigned char *pubkey,
int pubkeylen
-) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(4);
+) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3) SECP256K1_ARG_NONNULL(5);
/** A pointer to a function to deterministically generate a nonce.
* Returns: 1 if a nonce was successfully generated. 0 will cause signing to fail.
@@ -111,15 +129,14 @@ extern const secp256k1_nonce_function_t secp256k1_nonce_function_default;
* Returns: 1: signature created
* 0: the nonce generation function failed, the private key was invalid, or there is not
* enough space in the signature (as indicated by siglen).
- * In: msg32: the 32-byte message hash being signed (cannot be NULL)
+ * In: ctx: pointer to a context object, initialized for signing (cannot be NULL)
+ * msg32: the 32-byte message hash being signed (cannot be NULL)
* seckey: pointer to a 32-byte secret key (cannot be NULL)
* noncefp:pointer to a nonce generation function. If NULL, secp256k1_nonce_function_default is used
* ndata: pointer to arbitrary data used by the nonce generation function (can be NULL)
* Out: sig: pointer to an array where the signature will be placed (cannot be NULL)
* In/Out: siglen: pointer to an int with the length of sig, which will be updated
- * to contain the actual signature length (<=72). If 0 is returned, this will be
- * set to zero.
- * Requires starting using SECP256K1_START_SIGN.
+ * to contain the actual signature length (<=72).
*
* The sig always has an s value in the lower half of the range (From 0x1
* to 0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0,
@@ -148,145 +165,180 @@ extern const secp256k1_nonce_function_t secp256k1_nonce_function_default;
* be taken when this property is required for an application.
*/
int secp256k1_ecdsa_sign(
+ const secp256k1_context_t* ctx,
const unsigned char *msg32,
unsigned char *sig,
int *siglen,
const unsigned char *seckey,
secp256k1_nonce_function_t noncefp,
const void *ndata
-) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3) SECP256K1_ARG_NONNULL(4);
+) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3) SECP256K1_ARG_NONNULL(4) SECP256K1_ARG_NONNULL(5);
/** Create a compact ECDSA signature (64 byte + recovery id).
* Returns: 1: signature created
* 0: the nonce generation function failed, or the secret key was invalid.
- * In: msg32: the 32-byte message hash being signed (cannot be NULL)
+ * In: ctx: pointer to a context object, initialized for signing (cannot be NULL)
+ * msg32: the 32-byte message hash being signed (cannot be NULL)
* seckey: pointer to a 32-byte secret key (cannot be NULL)
* noncefp:pointer to a nonce generation function. If NULL, secp256k1_nonce_function_default is used
* ndata: pointer to arbitrary data used by the nonce generation function (can be NULL)
* Out: sig: pointer to a 64-byte array where the signature will be placed (cannot be NULL)
* In case 0 is returned, the returned signature length will be zero.
* recid: pointer to an int, which will be updated to contain the recovery id (can be NULL)
- * Requires starting using SECP256K1_START_SIGN.
*/
int secp256k1_ecdsa_sign_compact(
+ const secp256k1_context_t* ctx,
const unsigned char *msg32,
unsigned char *sig64,
const unsigned char *seckey,
secp256k1_nonce_function_t noncefp,
const void *ndata,
int *recid
-) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
+) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3) SECP256K1_ARG_NONNULL(4);
/** Recover an ECDSA public key from a compact signature.
* Returns: 1: public key successfully recovered (which guarantees a correct signature).
* 0: otherwise.
- * In: msg32: the 32-byte message hash assumed to be signed (cannot be NULL)
+ * In: ctx: pointer to a context object, initialized for verification (cannot be NULL)
+ * msg32: the 32-byte message hash assumed to be signed (cannot be NULL)
* sig64: signature as 64 byte array (cannot be NULL)
* compressed: whether to recover a compressed or uncompressed pubkey
* recid: the recovery id (0-3, as returned by ecdsa_sign_compact)
* Out: pubkey: pointer to a 33 or 65 byte array to put the pubkey (cannot be NULL)
* pubkeylen: pointer to an int that will contain the pubkey length (cannot be NULL)
- * Requires starting using SECP256K1_START_VERIFY.
*/
SECP256K1_WARN_UNUSED_RESULT int secp256k1_ecdsa_recover_compact(
+ const secp256k1_context_t* ctx,
const unsigned char *msg32,
const unsigned char *sig64,
unsigned char *pubkey,
int *pubkeylen,
int compressed,
int recid
-) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3) SECP256K1_ARG_NONNULL(4);
+) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3) SECP256K1_ARG_NONNULL(4) SECP256K1_ARG_NONNULL(5);
/** Verify an ECDSA secret key.
* Returns: 1: secret key is valid
* 0: secret key is invalid
- * In: seckey: pointer to a 32-byte secret key (cannot be NULL)
+ * In: ctx: pointer to a context object (cannot be NULL)
+ * seckey: pointer to a 32-byte secret key (cannot be NULL)
*/
-SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_seckey_verify(const unsigned char *seckey) SECP256K1_ARG_NONNULL(1);
+SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_seckey_verify(
+ const secp256k1_context_t* ctx,
+ const unsigned char *seckey
+) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2);
/** Just validate a public key.
- * Returns: 1: valid public key
- * 0: invalid public key
- * In: pubkey: pointer to a 33-byte or 65-byte public key (cannot be NULL).
+ * Returns: 1: public key is valid
+ * 0: public key is invalid
+ * In: ctx: pointer to a context object (cannot be NULL)
+ * pubkey: pointer to a 33-byte or 65-byte public key (cannot be NULL).
* pubkeylen: length of pubkey
*/
-SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_pubkey_verify(const unsigned char *pubkey, int pubkeylen) SECP256K1_ARG_NONNULL(1);
+SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_pubkey_verify(
+ const secp256k1_context_t* ctx,
+ const unsigned char *pubkey,
+ int pubkeylen
+) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2);
/** Compute the public key for a secret key.
- * In: compressed: whether the computed public key should be compressed
+ * In: ctx: pointer to a context object, initialized for signing (cannot be NULL)
+ * compressed: whether the computed public key should be compressed
* seckey: pointer to a 32-byte private key (cannot be NULL)
* Out: pubkey: pointer to a 33-byte (if compressed) or 65-byte (if uncompressed)
* area to store the public key (cannot be NULL)
* pubkeylen: pointer to int that will be updated to contains the pubkey's
* length (cannot be NULL)
* Returns: 1: secret was valid, public key stores
- * 0: secret was invalid, try again.
- * Requires starting using SECP256K1_START_SIGN.
+ * 0: secret was invalid, try again
*/
SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_pubkey_create(
+ const secp256k1_context_t* ctx,
unsigned char *pubkey,
int *pubkeylen,
const unsigned char *seckey,
int compressed
-) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
+) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3) SECP256K1_ARG_NONNULL(4);
/** Decompress a public key.
+ * In: ctx: pointer to a context object (cannot be NULL)
* In/Out: pubkey: pointer to a 65-byte array to put the decompressed public key.
- It must contain a 33-byte or 65-byte public key already (cannot be NULL)
+ * It must contain a 33-byte or 65-byte public key already (cannot be NULL)
* pubkeylen: pointer to the size of the public key pointed to by pubkey (cannot be NULL)
- It will be updated to reflect the new size.
- * Returns: 0 if the passed public key was invalid, 1 otherwise. If 1 is returned, the
- pubkey is replaced with its decompressed version.
+ * It will be updated to reflect the new size.
+ * Returns: 0: pubkey was invalid
+ * 1: pubkey was valid, and was replaced with its decompressed version
*/
SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_pubkey_decompress(
+ const secp256k1_context_t* ctx,
unsigned char *pubkey,
int *pubkeylen
-) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2);
+) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
-/** Export a private key in DER format. */
+/** Export a private key in DER format.
+ * In: ctx: pointer to a context object, initialized for signing (cannot be NULL)
+ */
SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_privkey_export(
+ const secp256k1_context_t* ctx,
const unsigned char *seckey,
unsigned char *privkey,
int *privkeylen,
int compressed
-) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
+) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3) SECP256K1_ARG_NONNULL(4);
/** Import a private key in DER format. */
SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_privkey_import(
+ const secp256k1_context_t* ctx,
unsigned char *seckey,
const unsigned char *privkey,
int privkeylen
-) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2);
+) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
/** Tweak a private key by adding tweak to it. */
SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_privkey_tweak_add(
+ const secp256k1_context_t* ctx,
unsigned char *seckey,
const unsigned char *tweak
-) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2);
+) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
/** Tweak a public key by adding tweak times the generator to it.
- * Requires starting with SECP256K1_START_VERIFY.
+ * In: ctx: pointer to a context object, initialized for verification (cannot be NULL)
*/
SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_pubkey_tweak_add(
+ const secp256k1_context_t* ctx,
unsigned char *pubkey,
int pubkeylen,
const unsigned char *tweak
-) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(3);
+) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(4);
/** Tweak a private key by multiplying it with tweak. */
SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_privkey_tweak_mul(
+ const secp256k1_context_t* ctx,
unsigned char *seckey,
const unsigned char *tweak
-) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2);
+) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
/** Tweak a public key by multiplying it with tweak.
- * Requires starting with SECP256K1_START_VERIFY.
+ * In: ctx: pointer to a context object, initialized for verification (cannot be NULL)
*/
SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_pubkey_tweak_mul(
+ const secp256k1_context_t* ctx,
unsigned char *pubkey,
int pubkeylen,
const unsigned char *tweak
-) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(3);
+) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(4);
+
+/** Updates the context randomization.
+ * Returns: 1: randomization successfully updated
+ * 0: error
+ * In: ctx: pointer to a context object (cannot be NULL)
+ * seed32: pointer to a 32-byte random seed (NULL resets to initial state)
+ */
+SECP256K1_WARN_UNUSED_RESULT int secp256k1_context_randomize(
+ secp256k1_context_t* ctx,
+ const unsigned char *seed32
+) SECP256K1_ARG_NONNULL(1);
+
# ifdef __cplusplus
}
generated by cgit v1.2.3 (git 2.26.2) at 2024-10-30 11:39:17 +0000