Merge pull request #562 from padelsbach/aes256-gcm-minimal
Add minimal buffer encrypt and decrypt example for AES-GCMpull/563/head
tmael
GitHub
commit
498d78e6d3
|
|
@ -136,6 +136,7 @@ crypto/aes/aescfb-file-encrypt
|
|||
crypto/aes/aesctr-file-encrypt
|
||||
crypto/aes/aesgcm-file-encrypt
|
||||
crypto/aes/aesgcm-oneshot
|
||||
crypto/aes/aesgcm-minimal
|
||||
crypto/camellia/camellia-encrypt
|
||||
crypto/pkcs12/pkcs12-create-example
|
||||
crypto/pkcs12/pkcs12-example
|
||||
|
|
|
|||
|
|
@ -3,7 +3,7 @@ CFLAGS=-Wall
|
|||
WOLFSSL_INSTALL_DIR=/usr/local
|
||||
LIBS=-L$(WOLFSSL_INSTALL_DIR)/lib -lwolfssl -lm
|
||||
|
||||
all: aes-file-encrypt aescfb-file-encrypt aesctr-file-encrypt aesgcm-file-encrypt aesgcm-oneshot
|
||||
all: aes-file-encrypt aescfb-file-encrypt aesctr-file-encrypt aesgcm-file-encrypt aesgcm-oneshot aesgcm-minimal
|
||||
|
||||
aes-file-encrypt: aes-file-encrypt.o
|
||||
$(CC) -o $@ $^ $(CFLAGS) $(LIBS)
|
||||
|
|
@ -20,7 +20,10 @@ aesgcm-file-encrypt: aesgcm-file-encrypt.o
|
|||
aesgcm-oneshot: aesgcm-oneshot.o
|
||||
$(CC) -o $@ $^ $(CFLAGS) $(LIBS)
|
||||
|
||||
aesgcm-minimal: aesgcm-minimal.o
|
||||
$(CC) -o $@ $^ $(CFLAGS) $(LIBS)
|
||||
|
||||
.PHONY: clean
|
||||
|
||||
clean:
|
||||
rm -f *.o aes-file-encrypt aescfb-file-encrypt aesctr-file-encrypt aesgcm-file-encrypt text* aesgcm-oneshot
|
||||
rm -f *.o aes-file-encrypt aescfb-file-encrypt aesctr-file-encrypt aesgcm-file-encrypt text* aesgcm-oneshot aesgcm-minimal
|
||||
|
|
|
|||
|
|
@ -0,0 +1,193 @@
|
|||
/* aesgcm-minimal.c
|
||||
*
|
||||
* Copyright (C) 2006-2026 wolfSSL Inc.
|
||||
*
|
||||
* This file is part of wolfSSL.
|
||||
*
|
||||
* wolfSSL is free software; you can redistribute it and/or modify
|
||||
* it under the terms of the GNU General Public License as published by
|
||||
* the Free Software Foundation; either version 2 of the License, or
|
||||
* (at your option) any later version.
|
||||
*
|
||||
* wolfSSL is distributed in the hope that it will be useful,
|
||||
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||||
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||||
* GNU General Public License for more details.
|
||||
*
|
||||
* You should have received a copy of the GNU General Public License
|
||||
* along with this program; if not, write to the Free Software
|
||||
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1335, USA
|
||||
*/
|
||||
|
||||
#ifndef WOLFSSL_USER_SETTINGS
|
||||
#include <wolfssl/options.h>
|
||||
#endif
|
||||
#include <wolfssl/wolfcrypt/aes.h>
|
||||
#include <wolfssl/wolfcrypt/error-crypt.h>
|
||||
#include <wolfssl/wolfcrypt/random.h>
|
||||
|
||||
#include <stdio.h>
|
||||
#include <string.h>
|
||||
|
||||
#define KEY_SZ AES_256_KEY_SIZE
|
||||
#define NONCE_SZ GCM_NONCE_MID_SZ
|
||||
#define TAG_SZ AES_BLOCK_SIZE
|
||||
|
||||
/* Optional setup path: seed wolfSSL RNG via RDSEED when available. */
|
||||
#if defined(__x86_64__)
|
||||
#define RDSEED_ENABLED 1
|
||||
#endif
|
||||
|
||||
#if defined(WC_RNG_SEED_CB) && defined(RDSEED_ENABLED)
|
||||
#include <immintrin.h>
|
||||
|
||||
/* wc_RngSeed_Cb: feed wolfSSL DRBG seed using RDSEED. */
|
||||
__attribute__((target("rdseed")))
|
||||
static int RdseedSeedCb(OS_Seed* os, byte* seed, word32 sz)
|
||||
{
|
||||
word32 i = 0;
|
||||
(void)os;
|
||||
|
||||
while (i < sz) {
|
||||
unsigned long long v = 0;
|
||||
int ok = 0;
|
||||
int tries;
|
||||
word32 n;
|
||||
|
||||
for (tries = 0; tries < 16; tries++) {
|
||||
if (_rdseed64_step(&v)) {
|
||||
ok = 1;
|
||||
break;
|
||||
}
|
||||
}
|
||||
if (!ok) {
|
||||
return RNG_FAILURE_E;
|
||||
}
|
||||
|
||||
n = (sz - i < (word32)sizeof(v)) ? (sz - i) : (word32)sizeof(v);
|
||||
memcpy(seed + i, &v, n);
|
||||
i += n;
|
||||
}
|
||||
return 0;
|
||||
}
|
||||
#endif
|
||||
|
||||
static int GenerateKeyAndIv(byte* key, byte* iv)
|
||||
{
|
||||
WC_RNG rng;
|
||||
int ret;
|
||||
|
||||
/* Setup: initialize RNG and (optionally) override seed source. */
|
||||
#if defined(WC_RNG_SEED_CB) && defined(RDSEED_ENABLED)
|
||||
wc_SetSeed_Cb(RdseedSeedCb);
|
||||
ret = wc_InitRng(&rng);
|
||||
wc_SetSeed_Cb(NULL);
|
||||
#else
|
||||
ret = wc_InitRng(&rng);
|
||||
#endif
|
||||
if (ret != 0) {
|
||||
return ret;
|
||||
}
|
||||
|
||||
ret = wc_RNG_GenerateBlock(&rng, key, KEY_SZ);
|
||||
if (ret == 0) {
|
||||
ret = wc_RNG_GenerateBlock(&rng, iv, NONCE_SZ);
|
||||
}
|
||||
wc_FreeRng(&rng);
|
||||
return ret;
|
||||
}
|
||||
|
||||
static int Encrypt(const byte* key, const byte* iv, const byte* plaintext,
|
||||
word32 plaintextSz, byte* ciphertext, byte* tag, const byte* aad,
|
||||
word32 aadSz)
|
||||
{
|
||||
int ret;
|
||||
Aes aes;
|
||||
|
||||
ret = wc_AesInit(&aes, NULL, INVALID_DEVID);
|
||||
if (ret == 0) {
|
||||
ret = wc_AesGcmSetKey(&aes, key, KEY_SZ);
|
||||
}
|
||||
if (ret == 0) {
|
||||
ret = wc_AesGcmEncrypt(&aes, ciphertext, plaintext, plaintextSz, iv,
|
||||
NONCE_SZ, tag, TAG_SZ, aad, aadSz);
|
||||
}
|
||||
wc_AesFree(&aes);
|
||||
return ret;
|
||||
}
|
||||
|
||||
static int Decrypt(const byte* key, const byte* iv, const byte* ciphertext,
|
||||
word32 ciphertextSz, byte* plaintext, const byte* tag, const byte* aad,
|
||||
word32 aadSz)
|
||||
{
|
||||
int ret;
|
||||
Aes aes;
|
||||
|
||||
ret = wc_AesInit(&aes, NULL, INVALID_DEVID);
|
||||
if (ret == 0) {
|
||||
ret = wc_AesGcmSetKey(&aes, key, KEY_SZ);
|
||||
}
|
||||
if (ret == 0) {
|
||||
ret = wc_AesGcmDecrypt(&aes, plaintext, ciphertext, ciphertextSz, iv,
|
||||
NONCE_SZ, tag, TAG_SZ, aad, aadSz);
|
||||
}
|
||||
wc_AesFree(&aes);
|
||||
return ret;
|
||||
}
|
||||
|
||||
void print_hex(const char* label, const byte* data, word32 sz)
|
||||
{
|
||||
printf("%s: ", label);
|
||||
for (word32 i = 0; i < sz; i++) {
|
||||
printf("%02x", data[i]);
|
||||
}
|
||||
printf("\n");
|
||||
}
|
||||
|
||||
int main(void)
|
||||
{
|
||||
/* Setup/example data and buffers. */
|
||||
byte key[KEY_SZ];
|
||||
const byte aad[] = "example-aad";
|
||||
const byte plaintext[] = "single block msg";
|
||||
byte decrypted[sizeof(plaintext)];
|
||||
byte iv[NONCE_SZ];
|
||||
byte ciphertext[sizeof(plaintext)];
|
||||
byte tag[TAG_SZ];
|
||||
int ret;
|
||||
|
||||
ret = GenerateKeyAndIv(key, iv);
|
||||
if (ret != 0) {
|
||||
printf("Key/IV generation failed: %d\n", ret);
|
||||
return 1;
|
||||
}
|
||||
print_hex("Plaintext", plaintext, sizeof(plaintext));
|
||||
print_hex(" Key", key, sizeof(key));
|
||||
print_hex(" IV", iv, sizeof(iv));
|
||||
|
||||
/* Encrypt with key + IV (+ optional AAD) to get tag. */
|
||||
ret = Encrypt(key, iv, plaintext, sizeof(plaintext), ciphertext, tag, aad,
|
||||
(word32)(sizeof(aad) - 1));
|
||||
if (ret != 0) {
|
||||
printf("Encryption failed: %d\n", ret);
|
||||
return 1;
|
||||
}
|
||||
print_hex("Ciphertext", ciphertext, sizeof(ciphertext));
|
||||
print_hex(" Auth Tag", tag, sizeof(tag));
|
||||
|
||||
/* Decrypt with the same key/IV/AAD and received tag. */
|
||||
ret = Decrypt(key, iv, ciphertext, sizeof(ciphertext), decrypted, tag, aad,
|
||||
(word32)(sizeof(aad) - 1));
|
||||
if (ret != 0) {
|
||||
printf("Decryption failed: %d\n", ret);
|
||||
return 1;
|
||||
}
|
||||
|
||||
if (memcmp(plaintext, decrypted, sizeof(plaintext)) != 0) {
|
||||
printf("Round-trip mismatch\n");
|
||||
return 1;
|
||||
}
|
||||
print_hex("Decrypted", decrypted, sizeof(decrypted));
|
||||
|
||||
return 0;
|
||||
}
|
||||
Loading…
Reference in New Issue