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@cannium
Last active September 19, 2024 21:06
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golang aes-256-gcm
package main
import (
"crypto/aes"
"crypto/cipher"
"crypto/rand"
"encoding/hex"
"fmt"
"io"
)
func ExampleNewGCMEncrypter() {
// The key argument should be the AES key, either 16 or 32 bytes
// to select AES-128 or AES-256.
key := []byte("AES256Key-32Characters1234567890")
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())
}
fmt.Printf("%x\n", nonce)
aesgcm, err := cipher.NewGCM(block)
if err != nil {
panic(err.Error())
}
ciphertext := aesgcm.Seal(nil, nonce, plaintext, nil)
fmt.Printf("%x\n", ciphertext)
}
func ExampleNewGCMDecrypter() {
// The key argument should be the AES key, either 16 or 32 bytes
// to select AES-128 or AES-256.
key := []byte("AES256Key-32Characters1234567890")
ciphertext, _ := hex.DecodeString("2df87baf86b5073ef1f03e3cc738de75b511400f5465bb0ddeacf47ae4dc267d")
nonce, _ := hex.DecodeString("afb8a7579bf971db9f8ceeed")
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)
// Output: exampleplaintext
}
func main() {
ExampleNewGCMEncrypter()
ExampleNewGCMDecrypter()
}
@Iptihar
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Iptihar commented Nov 10, 2017

cool stuff, like it, thanks for sharing !

@xeoncross
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xeoncross commented Mar 30, 2018

@tinti
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tinti commented May 23, 2018

@jrwren
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jrwren commented Feb 28, 2019

What is the magic string afb8a7579bf971db9f8ceeed on line 45?

@Codefor
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Codefor commented Apr 18, 2019

afb8a7579bf971db9f8ceeed should be the nonce outputed on line 28

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