Merge commit 'd48555b36ac512161b81f9b6bca7bea16a0cd806' as 'src/secp256k1'

1 files changed, 252 insertions, 0 deletions

diff --git a/src/secp256k1/include/secp256k1.h b/src/secp256k1/include/secp256k1.h
new file mode 100644
index 0000000000..932bf0279f
--- /dev/null
+++ b/src/secp256k1/include/secp256k1.h
@@ -0,0 +1,252 @@
+#ifndef _SECP256K1_
+# define _SECP256K1_
+
+# ifdef __cplusplus
+extern "C" {
+# endif
+
+# if !defined(SECP256K1_GNUC_PREREQ)
+#  if defined(__GNUC__)&&defined(__GNUC_MINOR__)
+#   define SECP256K1_GNUC_PREREQ(_maj,_min) \
+ ((__GNUC__<<16)+__GNUC_MINOR__>=((_maj)<<16)+(_min))
+#  else
+#   define SECP256K1_GNUC_PREREQ(_maj,_min) 0
+#  endif
+# endif
+
+# if (!defined(__STDC_VERSION__) || (__STDC_VERSION__ < 199901L) )
+#  if SECP256K1_GNUC_PREREQ(3,0)
+#   define SECP256K1_RESTRICT __restrict__
+#  elif (defined(_MSC_VER) && _MSC_VER >= 1400)
+#   define SECP256K1_RESTRICT __restrict
+#  else
+#   define SECP256K1_RESTRICT
+#  endif
+# else
+#  define SECP256K1_RESTRICT restrict
+# endif
+
+# if (!defined(__STDC_VERSION__) || (__STDC_VERSION__ < 199901L) )
+#  if SECP256K1_GNUC_PREREQ(2,7)
+#   define SECP256K1_INLINE __inline__
+#  elif (defined(_MSC_VER))
+#   define SECP256K1_INLINE __inline
+#  else
+#   define SECP256K1_INLINE
+#  endif
+# else
+#  define SECP256K1_INLINE inline
+# endif
+
+/**Warning attributes
+  * NONNULL is not used if SECP256K1_BUILD is set to avoid the compiler optimizing out
+  * some paranoid null checks. */
+# if defined(__GNUC__) && SECP256K1_GNUC_PREREQ(3, 4)
+#  define SECP256K1_WARN_UNUSED_RESULT __attribute__ ((__warn_unused_result__))
+# else
+#  define SECP256K1_WARN_UNUSED_RESULT
+# endif
+# if !defined(SECP256K1_BUILD) && defined(__GNUC__) && SECP256K1_GNUC_PREREQ(3, 4)
+#  define SECP256K1_ARG_NONNULL(_x)  __attribute__ ((__nonnull__(_x)))
+# else
+#  define SECP256K1_ARG_NONNULL(_x)
+# endif
+
+
+/** Flags to pass to secp256k1_start. */
+# define SECP256K1_START_VERIFY (1 << 0)
+# define SECP256K1_START_SIGN   (1 << 1)
+
+/** 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.
+ */
+void secp256k1_start(unsigned int flags);
+
+/** Free all memory associated with this library. After this, no
+ *  functions can be called anymore, except secp256k1_start()
+ */
+void secp256k1_stop(void);
+
+/** Verify an ECDSA signature.
+ *  Returns: 1: correct signature
+ *           0: incorrect signature
+ *          -1: invalid public key
+ *          -2: invalid signature
+ * In:       msg:       the message being verified (cannot be NULL)
+ *           msglen:    the length of the message (at most 32)
+ *           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 unsigned char *msg,
+  int msglen,
+  const unsigned char *sig,
+  int siglen,
+  const unsigned char *pubkey,
+  int pubkeylen
+) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(3) SECP256K1_ARG_NONNULL(5);
+
+/** Create an ECDSA signature.
+ *  Returns: 1: signature created
+ *           0: nonce invalid, try another one
+ *  In:      msg:    the message being signed (cannot be NULL)
+ *           msglen: the length of the message being signed (at most 32)
+ *           seckey: pointer to a 32-byte secret key (cannot be NULL, assumed to be valid)
+ *           nonce:  pointer to a 32-byte nonce (cannot be NULL, generated with a cryptographic PRNG)
+ *  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).
+ * Requires starting using SECP256K1_START_SIGN.
+ */
+SECP256K1_WARN_UNUSED_RESULT int secp256k1_ecdsa_sign(
+  const unsigned char *msg,
+  int msglen,
+  unsigned char *sig,
+  int *siglen,
+  const unsigned char *seckey,
+  const unsigned char *nonce
+) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(3) SECP256K1_ARG_NONNULL(4) SECP256K1_ARG_NONNULL(5) SECP256K1_ARG_NONNULL(6);
+
+/** Create a compact ECDSA signature (64 byte + recovery id).
+ *  Returns: 1: signature created
+ *           0: nonce invalid, try another one
+ *  In:      msg:    the message being signed (cannot be NULL)
+ *           msglen: the length of the message being signed (at most 32)
+ *           seckey: pointer to a 32-byte secret key (cannot be NULL, assumed to be valid)
+ *           nonce:  pointer to a 32-byte nonce (cannot be NULL, generated with a cryptographic PRNG)
+ *  Out:     sig:    pointer to a 64-byte array where the signature will be placed (cannot be NULL)
+ *           recid:  pointer to an int, which will be updated to contain the recovery id (can be NULL)
+ * Requires starting using SECP256K1_START_SIGN.
+ */
+SECP256K1_WARN_UNUSED_RESULT int secp256k1_ecdsa_sign_compact(
+  const unsigned char *msg,
+  int msglen,
+  unsigned char *sig64,
+  const unsigned char *seckey,
+  const unsigned char *nonce,
+  int *recid
+) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(3) SECP256K1_ARG_NONNULL(4) SECP256K1_ARG_NONNULL(5);
+
+/** Recover an ECDSA public key from a compact signature.
+ *  Returns: 1: public key successfully recovered (which guarantees a correct signature).
+ *           0: otherwise.
+ *  In:      msg:        the message assumed to be signed (cannot be NULL)
+ *           msglen:     the length of the message (at most 32)
+ *           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 unsigned char *msg,
+  int msglen,
+  const unsigned char *sig64,
+  unsigned char *pubkey,
+  int *pubkeylen,
+  int compressed,
+  int recid
+) SECP256K1_ARG_NONNULL(1) 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)
+ */
+SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_seckey_verify(const unsigned char *seckey) SECP256K1_ARG_NONNULL(1);
+
+/** 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).
+ *           pubkeylen: length of pubkey
+ */
+SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_pubkey_verify(const unsigned char *pubkey, int pubkeylen) SECP256K1_ARG_NONNULL(1);
+
+/** Compute the public key for a secret key.
+ *  In:     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.
+ */
+SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_pubkey_create(
+  unsigned char *pubkey,
+  int *pubkeylen,
+  const unsigned char *seckey,
+  int compressed
+) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
+
+/** Decompress a public key.
+ * 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)
+ *         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.
+ */
+SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_pubkey_decompress(
+  unsigned char *pubkey,
+  int *pubkeylen
+) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2);
+
+/** Export a private key in DER format. */
+SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_privkey_export(
+  const unsigned char *seckey,
+  unsigned char *privkey,
+  int *privkeylen,
+  int compressed
+) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
+
+/** Import a private key in DER format. */
+SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_privkey_import(
+  unsigned char *seckey,
+  const unsigned char *privkey,
+  int privkeylen
+) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2);
+
+/** Tweak a private key by adding tweak to it. */
+SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_privkey_tweak_add(
+  unsigned char *seckey,
+  const unsigned char *tweak
+) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2);
+
+/** Tweak a public key by adding tweak times the generator to it.
+ * Requires starting with SECP256K1_START_VERIFY.
+ */
+SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_pubkey_tweak_add(
+  unsigned char *pubkey,
+  int pubkeylen,
+  const unsigned char *tweak
+) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(3);
+
+/** Tweak a private key by multiplying it with tweak. */
+SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_privkey_tweak_mul(
+  unsigned char *seckey,
+  const unsigned char *tweak
+) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2);
+
+/** Tweak a public key by multiplying it with tweak.
+ * Requires starting with SECP256K1_START_VERIFY.
+ */
+SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_pubkey_tweak_mul(
+  unsigned char *pubkey,
+  int pubkeylen,
+  const unsigned char *tweak
+) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(3);
+
+# ifdef __cplusplus
+}
+# endif
+
+#endif