mirror of https://github.com/certusone/dc4bc.git
69 lines
1.2 KiB
Go
69 lines
1.2 KiB
Go
package airgapped
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import (
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"crypto/aes"
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"crypto/cipher"
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"crypto/rand"
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"fmt"
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"io"
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"math"
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"golang.org/x/crypto/scrypt"
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)
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var N = int(math.Pow(2, 16))
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func encrypt(key, salt, data []byte) ([]byte, error) {
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derivedKey, err := scrypt.Key(key, salt, N, 8, 1, 32)
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if err != nil {
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return nil, err
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}
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c, err := aes.NewCipher(derivedKey)
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if err != nil {
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return nil, err
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}
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gcm, err := cipher.NewGCM(c)
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if err != nil {
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return nil, err
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}
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nonce := make([]byte, gcm.NonceSize())
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if _, err = io.ReadFull(rand.Reader, nonce); err != nil {
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return nil, err
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}
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return gcm.Seal(nonce, nonce, data, nil), nil
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}
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func decrypt(key, salt, data []byte) ([]byte, error) {
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derivedKey, err := scrypt.Key(key, salt, N, 8, 1, 32)
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if err != nil {
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return nil, err
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}
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c, err := aes.NewCipher(derivedKey)
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if err != nil {
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return nil, err
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}
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gcm, err := cipher.NewGCM(c)
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if err != nil {
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return nil, err
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}
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nonceSize := gcm.NonceSize()
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if len(data) < nonceSize {
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return nil, fmt.Errorf("invalid data length")
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}
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nonce, ciphertext := data[:nonceSize], data[nonceSize:]
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decryptedData, err := gcm.Open(nil, nonce, ciphertext, nil)
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if err != nil {
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return nil, err
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}
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return decryptedData, nil
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}
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