github.com/k1rill-fedoseev/go-ethereum@v1.9.7/crypto/secp256k1/libsecp256k1/include/secp256k1_recovery.h (about) 1 #ifndef _SECP256K1_RECOVERY_ 2 # define _SECP256K1_RECOVERY_ 3 4 # include "secp256k1.h" 5 6 # ifdef __cplusplus 7 extern "C" { 8 # endif 9 10 /** Opaque data structured that holds a parsed ECDSA signature, 11 * supporting pubkey recovery. 12 * 13 * The exact representation of data inside is implementation defined and not 14 * guaranteed to be portable between different platforms or versions. It is 15 * however guaranteed to be 65 bytes in size, and can be safely copied/moved. 16 * If you need to convert to a format suitable for storage or transmission, use 17 * the secp256k1_ecdsa_signature_serialize_* and 18 * secp256k1_ecdsa_signature_parse_* functions. 19 * 20 * Furthermore, it is guaranteed that identical signatures (including their 21 * recoverability) will have identical representation, so they can be 22 * memcmp'ed. 23 */ 24 typedef struct { 25 unsigned char data[65]; 26 } secp256k1_ecdsa_recoverable_signature; 27 28 /** Parse a compact ECDSA signature (64 bytes + recovery id). 29 * 30 * Returns: 1 when the signature could be parsed, 0 otherwise 31 * Args: ctx: a secp256k1 context object 32 * Out: sig: a pointer to a signature object 33 * In: input64: a pointer to a 64-byte compact signature 34 * recid: the recovery id (0, 1, 2 or 3) 35 */ 36 SECP256K1_API int secp256k1_ecdsa_recoverable_signature_parse_compact( 37 const secp256k1_context* ctx, 38 secp256k1_ecdsa_recoverable_signature* sig, 39 const unsigned char *input64, 40 int recid 41 ) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3); 42 43 /** Convert a recoverable signature into a normal signature. 44 * 45 * Returns: 1 46 * Out: sig: a pointer to a normal signature (cannot be NULL). 47 * In: sigin: a pointer to a recoverable signature (cannot be NULL). 48 */ 49 SECP256K1_API int secp256k1_ecdsa_recoverable_signature_convert( 50 const secp256k1_context* ctx, 51 secp256k1_ecdsa_signature* sig, 52 const secp256k1_ecdsa_recoverable_signature* sigin 53 ) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3); 54 55 /** Serialize an ECDSA signature in compact format (64 bytes + recovery id). 56 * 57 * Returns: 1 58 * Args: ctx: a secp256k1 context object 59 * Out: output64: a pointer to a 64-byte array of the compact signature (cannot be NULL) 60 * recid: a pointer to an integer to hold the recovery id (can be NULL). 61 * In: sig: a pointer to an initialized signature object (cannot be NULL) 62 */ 63 SECP256K1_API int secp256k1_ecdsa_recoverable_signature_serialize_compact( 64 const secp256k1_context* ctx, 65 unsigned char *output64, 66 int *recid, 67 const secp256k1_ecdsa_recoverable_signature* sig 68 ) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3) SECP256K1_ARG_NONNULL(4); 69 70 /** Create a recoverable ECDSA signature. 71 * 72 * Returns: 1: signature created 73 * 0: the nonce generation function failed, or the private key was invalid. 74 * Args: ctx: pointer to a context object, initialized for signing (cannot be NULL) 75 * Out: sig: pointer to an array where the signature will be placed (cannot be NULL) 76 * In: msg32: the 32-byte message hash being signed (cannot be NULL) 77 * seckey: pointer to a 32-byte secret key (cannot be NULL) 78 * noncefp:pointer to a nonce generation function. If NULL, secp256k1_nonce_function_default is used 79 * ndata: pointer to arbitrary data used by the nonce generation function (can be NULL) 80 */ 81 SECP256K1_API int secp256k1_ecdsa_sign_recoverable( 82 const secp256k1_context* ctx, 83 secp256k1_ecdsa_recoverable_signature *sig, 84 const unsigned char *msg32, 85 const unsigned char *seckey, 86 secp256k1_nonce_function noncefp, 87 const void *ndata 88 ) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3) SECP256K1_ARG_NONNULL(4); 89 90 /** Recover an ECDSA public key from a signature. 91 * 92 * Returns: 1: public key successfully recovered (which guarantees a correct signature). 93 * 0: otherwise. 94 * Args: ctx: pointer to a context object, initialized for verification (cannot be NULL) 95 * Out: pubkey: pointer to the recovered public key (cannot be NULL) 96 * In: sig: pointer to initialized signature that supports pubkey recovery (cannot be NULL) 97 * msg32: the 32-byte message hash assumed to be signed (cannot be NULL) 98 */ 99 SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_ecdsa_recover( 100 const secp256k1_context* ctx, 101 secp256k1_pubkey *pubkey, 102 const secp256k1_ecdsa_recoverable_signature *sig, 103 const unsigned char *msg32 104 ) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3) SECP256K1_ARG_NONNULL(4); 105 106 # ifdef __cplusplus 107 } 108 # endif 109 110 #endif