1 // Copyright (c) 2013-2014 The btcsuite developers
2 // Copyright (c) 2015-2022 The Decred developers
3 // Use of this source code is governed by an ISC
4 // license that can be found in the LICENSE file.
5 6 /*
7 Package secp256k1 implements optimized secp256k1 elliptic curve operations in
8 pure Go.
9 10 This package provides an optimized pure Go implementation of elliptic curve
11 cryptography operations over the secp256k1 curve as well as data structures and
12 functions for working with public and private secp256k1 keys. See
13 https://www.secg.org/sec2-v2.pdf for details on the standard.
14 15 In addition, sub packages are provided to produce, verify, parse, and serialize
16 ECDSA signatures and EC-Schnorr-DCRv0 (a custom Schnorr-based signature scheme
17 specific to Decred) signatures. See the README.md files in the relevant sub
18 packages for more details about those aspects.
19 20 An overview of the features provided by this package are as follows:
21 22 - Private key generation, serialization, and parsing
23 - Public key generation, serialization and parsing per ANSI X9.62-1998
24 - Parses uncompressed, compressed, and hybrid public keys
25 - Serializes uncompressed and compressed public keys
26 - Specialized types for performing optimized and constant time field operations
27 - FieldVal type for working modulo the secp256k1 field prime
28 - ModNScalar type for working modulo the secp256k1 group order
29 - Elliptic curve operations in Jacobian projective coordinates
30 - Point addition
31 - Point doubling
32 - Scalar multiplication with an arbitrary point
33 - Scalar multiplication with the base point (group generator)
34 - Point decompression from a given x coordinate
35 - Nonce generation via RFC6979 with support for extra data and version
36 information that can be used to prevent nonce reuse between signing
37 algorithms
38 39 It also provides an implementation of the Go standard library crypto/elliptic
40 Curve interface via the S256 function so that it may be used with other packages
41 in the standard library such as crypto/tls, crypto/x509, and crypto/ecdsa.
42 However, in the case of ECDSA, it is highly recommended to use the ecdsa sub
43 package of this package instead since it is optimized specifically for secp256k1
44 and is significantly faster as a result.
45 46 Although this package was primarily written for dcrd, it has intentionally been
47 designed so it can be used as a standalone package for any projects needing to
48 use optimized secp256k1 elliptic curve cryptography.
49 50 Finally, a comprehensive suite of tests is provided to provide a high level of
51 quality assurance.
52 53 # Use of secp256k1 in Decred
54 55 At the time of this writing, the primary public key cryptography in widespread
56 use on the Decred network used to secure coins is based on elliptic curves
57 defined by the secp256k1 domain parameters.
58 */
59 package secp256k1
60