initial addition of essential crypto, encoders, workflows and LLM instructions

pkg/crypto/ec/secp256k1/error.go

@@ -0,0 +1,56 @@
+// Copyright (c) 2020 The Decred developers
+// Use of this source code is governed by an ISC
+// license that can be found in the LICENSE file.
+
+package secp256k1
+
+// ErrorKind identifies a kind of error.  It has full support for errors.Is and
+// errors.As, so the caller can directly check against an error kind when
+// determining the reason for an error.
+type ErrorKind string
+
+// These constants are used to identify a specific RuleError.
+const (
+	// ErrPubKeyInvalidLen indicates that the length of a serialized public
+	// key is not one of the allowed lengths.
+	ErrPubKeyInvalidLen = ErrorKind("ErrPubKeyInvalidLen")
+	// ErrPubKeyInvalidFormat indicates an attempt was made to parse a public
+	// key that does not specify one of the supported formats.
+	ErrPubKeyInvalidFormat = ErrorKind("ErrPubKeyInvalidFormat")
+	// ErrPubKeyXTooBig indicates that the x coordinate for a public key
+	// is greater than or equal to the prime of the field underlying the group.
+	ErrPubKeyXTooBig = ErrorKind("ErrPubKeyXTooBig")
+	// ErrPubKeyYTooBig indicates that the y coordinate for a public key is
+	// greater than or equal to the prime of the field underlying the group.
+	ErrPubKeyYTooBig = ErrorKind("ErrPubKeyYTooBig")
+	// ErrPubKeyNotOnCurve indicates that a public key is not a point on the
+	// secp256k1 curve.
+	ErrPubKeyNotOnCurve = ErrorKind("ErrPubKeyNotOnCurve")
+	// ErrPubKeyMismatchedOddness indicates that a hybrid public key specified
+	// an oddness of the y coordinate that does not match the actual oddness of
+	// the provided y coordinate.
+	ErrPubKeyMismatchedOddness = ErrorKind("ErrPubKeyMismatchedOddness")
+)
+
+// Error satisfies the error interface and prints human-readable errors.
+func (err ErrorKind) Error() string { return string(err) }
+
+// Error identifies an error related to public key cryptography using a
+// sec256k1 curve. It has full support for errors.Is and errors.As, so the
+// caller can  ascertain the specific reason for the error by checking
+// the underlying error.
+type Error struct {
+	Err         error
+	Description string
+}
+
+// Error satisfies the error interface and prints human-readable errors.
+func (err Error) Error() string { return err.Description }
+
+// Unwrap returns the underlying wrapped error.
+func (err Error) Unwrap() (ee error) { return err.Err }
+
+// makeError creates an Error given a set of arguments.
+func makeError(kind ErrorKind, desc string) (err error) {
+	return Error{Err: kind, Description: desc}
+}