FIX GCM counter bug, change inc128 to inc32

This commit is contained in:
Zhi Guan
2024-04-21 23:58:01 +08:00
parent 252c9e1765
commit b2e334bfb9
2 changed files with 125 additions and 19 deletions

View File

@@ -121,6 +121,32 @@ void aes_ctr_encrypt(const AES_KEY *key, uint8_t ctr[16], const uint8_t *in, siz
}
}
static void ctr32_incr(uint8_t a[16])
{
int i;
for (i = 15; i >= 12; i--) {
a[i]++;
if (a[i]) break;
}
}
static void aes_ctr32_encrypt(const AES_KEY *key, uint8_t ctr[16], const uint8_t *in, size_t inlen, uint8_t *out)
{
uint8_t block[16];
size_t len;
while (inlen) {
len = inlen < 16 ? inlen : 16;
aes_encrypt(key, ctr, block);
gmssl_memxor(out, in, block, len);
ctr32_incr(ctr);
in += len;
out += len;
inlen -= len;
}
}
int aes_gcm_encrypt(const AES_KEY *key, const uint8_t *iv, size_t ivlen,
const uint8_t *aad, size_t aadlen, const uint8_t *in, size_t inlen,
uint8_t *out, size_t taglen, uint8_t *tag)
@@ -149,8 +175,8 @@ int aes_gcm_encrypt(const AES_KEY *key, const uint8_t *iv, size_t ivlen,
aes_encrypt(key, Y, T);
ctr_incr(Y);
aes_ctr_encrypt(key, Y, in, inlen, out);
ctr32_incr(Y);
aes_ctr32_encrypt(key, Y, in, inlen, out);
ghash(H, aad, aadlen, out, inlen, H);
gmssl_memxor(tag, T, H, taglen);
@@ -186,8 +212,8 @@ int aes_gcm_decrypt(const AES_KEY *key, const uint8_t *iv, size_t ivlen,
return -1;
}
ctr_incr(Y);
aes_ctr_encrypt(key, Y, in, inlen, out);
ctr32_incr(Y);
aes_ctr32_encrypt(key, Y, in, inlen, out);
return 1;
}

View File

@@ -12,17 +12,35 @@
#include <gmssl/mem.h>
#include <gmssl/ghash.h>
#include <gmssl/error.h>
#include <gmssl/endian.h>
static void ctr_incr(uint8_t a[16])
// inc32() in nist-sp800-38d
static void ctr32_incr(uint8_t a[16])
{
int i;
for (i = 15; i >= 0; i--) {
for (i = 15; i >= 12; i--) {
a[i]++;
if (a[i]) break;
}
}
static void sm4_ctr32_encrypt(const SM4_KEY *key, uint8_t ctr[16], const uint8_t *in, size_t inlen, uint8_t *out)
{
uint8_t block[16];
size_t len;
while (inlen) {
len = inlen < 16 ? inlen : 16;
sm4_encrypt(key, ctr, block);
gmssl_memxor(out, in, block, len);
ctr32_incr(ctr);
in += len;
out += len;
inlen -= len;
}
}
int sm4_gcm_encrypt(const SM4_KEY *key, const uint8_t *iv, size_t ivlen,
const uint8_t *aad, size_t aadlen, const uint8_t *in, size_t inlen,
uint8_t *out, size_t taglen, uint8_t *tag)
@@ -48,8 +66,8 @@ int sm4_gcm_encrypt(const SM4_KEY *key, const uint8_t *iv, size_t ivlen,
sm4_encrypt(key, Y, T);
ctr_incr(Y);
sm4_ctr_encrypt(key, Y, in, inlen, out);
ctr32_incr(Y);
sm4_ctr32_encrypt(key, Y, in, inlen, out);
ghash(H, aad, aadlen, out, inlen, H);
gmssl_memxor(tag, T, H, taglen);
@@ -84,12 +102,75 @@ int sm4_gcm_decrypt(const SM4_KEY *key, const uint8_t *iv, size_t ivlen,
return -1;
}
ctr_incr(Y);
sm4_ctr_encrypt(key, Y, in, inlen, out);
ctr32_incr(Y);
sm4_ctr32_encrypt(key, Y, in, inlen, out);
return 1;
}
static int sm4_ctr32_encrypt_init(SM4_CTR_CTX *ctx,
const uint8_t key[SM4_BLOCK_SIZE], const uint8_t ctr[SM4_BLOCK_SIZE])
{
sm4_set_encrypt_key(&ctx->sm4_key, key);
memcpy(ctx->ctr, ctr, SM4_BLOCK_SIZE);
memset(ctx->block, 0, SM4_BLOCK_SIZE);
ctx->block_nbytes = 0;
return 1;
}
static int sm4_ctr32_encrypt_update(SM4_CTR_CTX *ctx,
const uint8_t *in, size_t inlen, uint8_t *out, size_t *outlen)
{
size_t left;
size_t nblocks;
size_t len;
if (ctx->block_nbytes >= SM4_BLOCK_SIZE) {
error_print();
return -1;
}
*outlen = 0;
if (ctx->block_nbytes) {
left = SM4_BLOCK_SIZE - ctx->block_nbytes;
if (inlen < left) {
memcpy(ctx->block + ctx->block_nbytes, in, inlen);
ctx->block_nbytes += inlen;
return 1;
}
memcpy(ctx->block + ctx->block_nbytes, in, left);
sm4_ctr32_encrypt(&ctx->sm4_key, ctx->ctr, ctx->block, SM4_BLOCK_SIZE, out);
in += left;
inlen -= left;
out += SM4_BLOCK_SIZE;
*outlen += SM4_BLOCK_SIZE;
}
if (inlen >= SM4_BLOCK_SIZE) {
nblocks = inlen / SM4_BLOCK_SIZE;
len = nblocks * SM4_BLOCK_SIZE;
sm4_ctr32_encrypt(&ctx->sm4_key, ctx->ctr, in, len, out);
in += len;
inlen -= len;
out += len;
*outlen += len;
}
if (inlen) {
memcpy(ctx->block, in, inlen);
}
ctx->block_nbytes = inlen;
return 1;
}
static int sm4_ctr32_encrypt_finish(SM4_CTR_CTX *ctx, uint8_t *out, size_t *outlen)
{
if (ctx->block_nbytes >= SM4_BLOCK_SIZE) {
error_print();
return -1;
}
sm4_ctr32_encrypt(&ctx->sm4_key, ctx->ctr, ctx->block, ctx->block_nbytes, out);
*outlen = ctx->block_nbytes;
return 1;
}
int sm4_gcm_encrypt_init(SM4_GCM_CTX *ctx,
const uint8_t *key, size_t keylen, const uint8_t *iv, size_t ivlen,
const uint8_t *aad, size_t aadlen, size_t taglen)
@@ -117,7 +198,7 @@ int sm4_gcm_encrypt_init(SM4_GCM_CTX *ctx,
memset(ctx, 0, sizeof(*ctx));
ctx->taglen = taglen;
if (sm4_ctr_encrypt_init(&ctx->enc_ctx, key, H) != 1) {
if (sm4_ctr32_encrypt_init(&ctx->enc_ctx, key, H) != 1) {
error_print();
return -1;
}
@@ -136,7 +217,7 @@ int sm4_gcm_encrypt_init(SM4_GCM_CTX *ctx,
sm4_encrypt(&ctx->enc_ctx.sm4_key, Y, ctx->Y);
ctr_incr(Y);
ctr32_incr(Y);
memcpy(ctx->enc_ctx.ctr, Y, 16);
gmssl_secure_clear(H, sizeof(H));
@@ -150,7 +231,7 @@ int sm4_gcm_encrypt_update(SM4_GCM_CTX *ctx, const uint8_t *in, size_t inlen, ui
error_print();
return -1;
}
if (sm4_ctr_encrypt_update(&ctx->enc_ctx, in, inlen, out, outlen) != 1) {
if (sm4_ctr32_encrypt_update(&ctx->enc_ctx, in, inlen, out, outlen) != 1) {
error_print();
return -1;
}
@@ -166,7 +247,7 @@ int sm4_gcm_encrypt_finish(SM4_GCM_CTX *ctx, uint8_t *out, size_t *outlen)
error_print();
return -1;
}
if (sm4_ctr_encrypt_finish(&ctx->enc_ctx, out, outlen) != 1) {
if (sm4_ctr32_encrypt_finish(&ctx->enc_ctx, out, outlen) != 1) {
error_print();
return -1;
}
@@ -217,7 +298,7 @@ int sm4_gcm_decrypt_update(SM4_GCM_CTX *ctx, const uint8_t *in, size_t inlen, ui
if (inlen <= ctx->taglen) {
uint8_t tmp[GHASH_SIZE];
ghash_update(&ctx->mac_ctx, ctx->mac, inlen);
if (sm4_ctr_encrypt_update(&ctx->enc_ctx, ctx->mac, inlen, out, outlen) != 1) {
if (sm4_ctr32_encrypt_update(&ctx->enc_ctx, ctx->mac, inlen, out, outlen) != 1) {
error_print();
return -1;
}
@@ -227,7 +308,7 @@ int sm4_gcm_decrypt_update(SM4_GCM_CTX *ctx, const uint8_t *in, size_t inlen, ui
memcpy(ctx->mac, tmp, GHASH_SIZE);
} else {
ghash_update(&ctx->mac_ctx, ctx->mac, ctx->taglen);
if (sm4_ctr_encrypt_update(&ctx->enc_ctx, ctx->mac, ctx->taglen, out, outlen) != 1) {
if (sm4_ctr32_encrypt_update(&ctx->enc_ctx, ctx->mac, ctx->taglen, out, outlen) != 1) {
error_print();
return -1;
}
@@ -235,7 +316,7 @@ int sm4_gcm_decrypt_update(SM4_GCM_CTX *ctx, const uint8_t *in, size_t inlen, ui
inlen -= ctx->taglen;
ghash_update(&ctx->mac_ctx, in, inlen);
if (sm4_ctr_encrypt_update(&ctx->enc_ctx, in, inlen, out, &len) != 1) {
if (sm4_ctr32_encrypt_update(&ctx->enc_ctx, in, inlen, out, &len) != 1) {
error_print();
return -1;
}
@@ -258,7 +339,7 @@ int sm4_gcm_decrypt_finish(SM4_GCM_CTX *ctx, uint8_t *out, size_t *outlen)
return -1;
}
ghash_finish(&ctx->mac_ctx, mac);
if (sm4_ctr_encrypt_finish(&ctx->enc_ctx, out, outlen) != 1) {
if (sm4_ctr32_encrypt_finish(&ctx->enc_ctx, out, outlen) != 1) {
error_print();
return -1;
}
@@ -272,4 +353,3 @@ int sm4_gcm_decrypt_finish(SM4_GCM_CTX *ctx, uint8_t *out, size_t *outlen)
ctx->maclen = 0;
return 1;
}