GO NewGCM用法及代碼示例

GO語言"crypto/cipher"包中"NewGCM"函數的用法及代碼示例。

用法:

func NewGCM(cipher Block)(AEAD, error)

NewGCM 返回給定的 128 位分組密碼，以標準隨機數長度包裝在伽羅瓦計數器模式中。

一般來說，這種 GCM 實現執行的 GHASH 操作不是constant-time。一個例外是當底層塊由 aes NewCipher 在硬件支持 AES 的係統上創建時。有關詳細信息，請參閱 crypto/aes 包文檔。

示例(解密)：

package main

import (
	"crypto/aes"
	"crypto/cipher"
	"encoding/hex"
	"fmt"
)

func main() {
	// Load your secret key from a safe place and reuse it across multiple
	// Seal/Open calls. (Obviously don't use this example key for anything
	// real.) If you want to convert a passphrase to a key, use a suitable
	// package like bcrypt or scrypt.
	// When decoded the key should be 16 bytes (AES-128) or 32 (AES-256).
	key, _ := hex.DecodeString("6368616e676520746869732070617373776f726420746f206120736563726574")
	ciphertext, _ := hex.DecodeString("c3aaa29f002ca75870806e44086700f62ce4d43e902b3888e23ceff797a7a471")
	nonce, _ := hex.DecodeString("64a9433eae7ccceee2fc0eda")

	block, err := aes.NewCipher(key)
	if err != nil {
		panic(err.Error())
	}

	aesgcm, err := cipher.NewGCM(block)
	if err != nil {
		panic(err.Error())
	}

	plaintext, err := aesgcm.Open(nil, nonce, ciphertext, nil)
	if err != nil {
		panic(err.Error())
	}

	fmt.Printf("%s\n", plaintext)
}

輸出：

exampleplaintext

示例(加密)：

package main

import (
	"crypto/aes"
	"crypto/cipher"
	"crypto/rand"
	"encoding/hex"
	"fmt"
	"io"
)

func main() {
	// Load your secret key from a safe place and reuse it across multiple
	// Seal/Open calls. (Obviously don't use this example key for anything
	// real.) If you want to convert a passphrase to a key, use a suitable
	// package like bcrypt or scrypt.
	// When decoded the key should be 16 bytes (AES-128) or 32 (AES-256).
	key, _ := hex.DecodeString("6368616e676520746869732070617373776f726420746f206120736563726574")
	plaintext := []byte("exampleplaintext")

	block, err := aes.NewCipher(key)
	if err != nil {
		panic(err.Error())
	}

	// Never use more than 2^32 random nonces with a given key because of the risk of a repeat.
	nonce := make([]byte, 12)
	if _, err := io.ReadFull(rand.Reader, nonce); err != nil {
		panic(err.Error())
	}

	aesgcm, err := cipher.NewGCM(block)
	if err != nil {
		panic(err.Error())
	}

	ciphertext := aesgcm.Seal(nil, nonce, plaintext, nil)
	fmt.Printf("%x\n", ciphertext)
}

相關用法

注：本文由純淨天空篩選整理自golang.google.cn大神的英文原創作品 NewGCM。非經特殊聲明，原始代碼版權歸原作者所有，本譯文未經允許或授權，請勿轉載或複製。