38 lines
1.0 KiB
Go
38 lines
1.0 KiB
Go
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// Copyright 2020 the Pinniped contributors. All Rights Reserved.
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// SPDX-License-Identifier: Apache-2.0
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package state
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import (
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"crypto/rand"
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"crypto/subtle"
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"encoding/hex"
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"io"
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"github.com/pkg/errors"
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)
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// Generate generates a new random state parameter of an appropriate size.
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func Generate() (State, error) { return generate(rand.Reader) }
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func generate(rand io.Reader) (State, error) {
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var buf [16]byte
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if _, err := io.ReadFull(rand, buf[:]); err != nil {
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return "", errors.WithMessage(err, "could not generate random state")
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}
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return State(hex.EncodeToString(buf[:])), nil
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}
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// State implements some utilities for working with OAuth2 state parameters.
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type State string
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// String returns the string encoding of this state value.
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func (s *State) String() string {
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return string(*s)
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}
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// Validate the returned state (from a callback parameter). Returns true iff the state is valid.
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func (s *State) Valid(returnedState string) bool {
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return subtle.ConstantTimeCompare([]byte(returnedState), []byte(*s)) == 1
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}
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