92 lines
2.5 KiB
Go
92 lines
2.5 KiB
Go
// Copyright 2012 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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package packet
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import (
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"crypto"
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"crypto/rand"
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"io"
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"time"
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)
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// Config collects a number of parameters along with sensible defaults.
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// A nil *Config is valid and results in all default values.
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type Config struct {
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// Rand provides the source of entropy.
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// If nil, the crypto/rand Reader is used.
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Rand io.Reader
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// DefaultHash is the default hash function to be used.
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// If zero, SHA-256 is used.
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DefaultHash crypto.Hash
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// DefaultCipher is the cipher to be used.
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// If zero, AES-128 is used.
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DefaultCipher CipherFunction
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// Time returns the current time as the number of seconds since the
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// epoch. If Time is nil, time.Now is used.
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Time func() time.Time
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// DefaultCompressionAlgo is the compression algorithm to be
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// applied to the plaintext before encryption. If zero, no
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// compression is done.
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DefaultCompressionAlgo CompressionAlgo
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// CompressionConfig configures the compression settings.
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CompressionConfig *CompressionConfig
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// S2KCount is only used for symmetric encryption. It
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// determines the strength of the passphrase stretching when
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// the said passphrase is hashed to produce a key. S2KCount
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// should be between 1024 and 65011712, inclusive. If Config
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// is nil or S2KCount is 0, the value 65536 used. Not all
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// values in the above range can be represented. S2KCount will
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// be rounded up to the next representable value if it cannot
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// be encoded exactly. When set, it is strongly encrouraged to
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// use a value that is at least 65536. See RFC 4880 Section
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// 3.7.1.3.
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S2KCount int
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// RSABits is the number of bits in new RSA keys made with NewEntity.
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// If zero, then 2048 bit keys are created.
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RSABits int
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}
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func (c *Config) Random() io.Reader {
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if c == nil || c.Rand == nil {
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return rand.Reader
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}
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return c.Rand
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}
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func (c *Config) Hash() crypto.Hash {
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if c == nil || uint(c.DefaultHash) == 0 {
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return crypto.SHA256
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}
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return c.DefaultHash
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}
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func (c *Config) Cipher() CipherFunction {
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if c == nil || uint8(c.DefaultCipher) == 0 {
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return CipherAES128
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}
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return c.DefaultCipher
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}
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func (c *Config) Now() time.Time {
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if c == nil || c.Time == nil {
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return time.Now()
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}
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return c.Time()
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}
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func (c *Config) Compression() CompressionAlgo {
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if c == nil {
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return CompressionNone
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}
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return c.DefaultCompressionAlgo
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}
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func (c *Config) PasswordHashIterations() int {
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if c == nil || c.S2KCount == 0 {
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return 0
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}
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return c.S2KCount
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}
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