Created
August 19, 2019 03:48
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encrypt decrypt
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package main | |
import ( | |
"crypto/aes" | |
"crypto/cipher" | |
"crypto/sha256" | |
"encoding/base64" | |
"encoding/hex" | |
"fmt" | |
) | |
var ( | |
KEY = []byte("rappier_simple_secret_key") | |
IV = []byte("rappier_simple_secret_iv") | |
) | |
func main() { | |
h := sha256.New() | |
h.Write(KEY) | |
KEY = h.Sum(nil) | |
h.Reset() | |
h.Write(IV) | |
IV = h.Sum(nil)[:16] | |
fmt.Println("Key", hex.EncodeToString(KEY)) | |
fmt.Println("IV", hex.EncodeToString(IV)) | |
// This ciphertext was generated by the PHP module | |
de := "rDAnykzTorR5/SgpdD7slA==" | |
q, err := decrypt(KEY, IV, de) | |
fmt.Println(string(q), err) | |
} | |
// Returns slice of the original data without padding. | |
func pkcs7Unpad(data []byte, blocklen int) ([]byte, error) { | |
if blocklen <= 0 { | |
return nil, fmt.Errorf("invalid blocklen %d", blocklen) | |
} | |
if len(data)%blocklen != 0 || len(data) == 0 { | |
return nil, fmt.Errorf("invalid data len %d", len(data)) | |
} | |
padlen := int(data[len(data)-1]) | |
if padlen > blocklen || padlen == 0 { | |
return nil, fmt.Errorf("invalid padding") | |
} | |
// check padding | |
pad := data[len(data)-padlen:] | |
for i := 0; i < padlen; i++ { | |
if pad[i] != byte(padlen) { | |
return nil, fmt.Errorf("invalid padding") | |
} | |
} | |
return data[:len(data)-padlen], nil | |
} | |
func decrypt(key []byte, iv []byte, encrypted string) ([]byte, error) { | |
data, err := base64.StdEncoding.DecodeString(encrypted) | |
if err != nil { | |
return nil, err | |
} | |
if len(data) == 0 || len(data)%aes.BlockSize != 0 { | |
return nil, fmt.Errorf("bad blocksize(%v), aes.BlockSize = %v\n", len(data), aes.BlockSize) | |
} | |
c, err := aes.NewCipher(key) | |
if err != nil { | |
return nil, err | |
} | |
cbc := cipher.NewCBCDecrypter(c, iv) | |
cbc.CryptBlocks(data, data) | |
out, err := pkcs7Unpad(data, aes.BlockSize) | |
if err != nil { | |
return out, err | |
} | |
return out, nil | |
} |
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