openssl/providers/implementations/ciphers/cipher_aes_wrp.c
Matt Caswell 4b9c750be8 Make sure we handle input NULL with length 0
If we call EVP_EncryptUpdate/EVP_DecryptUpdate with length 0 we should
be able to handle it. Most importantly we shouldn't get different
results if we do this compared to if we don't!

An exception is made for CCM mode which has special handling for this in
the low level cipher function.

Fixes #8675

Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/10530)
2019-11-29 10:41:06 +00:00

247 lines
9.1 KiB
C

/*
* Copyright 2019 The OpenSSL Project Authors. All Rights Reserved.
*
* Licensed under the Apache License 2.0 (the "License"). You may not use
* this file except in compliance with the License. You can obtain a copy
* in the file LICENSE in the source distribution or at
* https://www.openssl.org/source/license.html
*/
#include "cipher_aes.h"
#include "prov/providercommonerr.h"
#include "prov/implementations.h"
/* AES wrap with padding has IV length of 4, without padding 8 */
#define AES_WRAP_PAD_IVLEN 4
#define AES_WRAP_NOPAD_IVLEN 8
/* TODO(3.0) Figure out what flags need to be passed */
#define WRAP_FLAGS (EVP_CIPH_WRAP_MODE | EVP_CIPH_CUSTOM_IV \
| EVP_CIPH_ALWAYS_CALL_INIT)
typedef size_t (*aeswrap_fn)(void *key, const unsigned char *iv,
unsigned char *out, const unsigned char *in,
size_t inlen, block128_f block);
static OSSL_OP_cipher_encrypt_init_fn aes_wrap_einit;
static OSSL_OP_cipher_decrypt_init_fn aes_wrap_dinit;
static OSSL_OP_cipher_update_fn aes_wrap_cipher;
static OSSL_OP_cipher_final_fn aes_wrap_final;
static OSSL_OP_cipher_freectx_fn aes_wrap_freectx;
typedef struct prov_aes_wrap_ctx_st {
PROV_CIPHER_CTX base;
union {
OSSL_UNION_ALIGN;
AES_KEY ks;
} ks;
aeswrap_fn wrapfn;
} PROV_AES_WRAP_CTX;
static void *aes_wrap_newctx(size_t kbits, size_t blkbits,
size_t ivbits, unsigned int mode, uint64_t flags)
{
PROV_AES_WRAP_CTX *wctx = OPENSSL_zalloc(sizeof(*wctx));
PROV_CIPHER_CTX *ctx = (PROV_CIPHER_CTX *)wctx;
if (ctx != NULL) {
cipher_generic_initkey(ctx, kbits, blkbits, ivbits, mode, flags,
NULL, NULL);
ctx->pad = (ctx->ivlen == AES_WRAP_PAD_IVLEN);
}
return wctx;
}
static void aes_wrap_freectx(void *vctx)
{
PROV_AES_WRAP_CTX *wctx = (PROV_AES_WRAP_CTX *)vctx;
OPENSSL_clear_free(wctx, sizeof(*wctx));
}
static int aes_wrap_init(void *vctx, const unsigned char *key,
size_t keylen, const unsigned char *iv,
size_t ivlen, int enc)
{
PROV_CIPHER_CTX *ctx = (PROV_CIPHER_CTX *)vctx;
PROV_AES_WRAP_CTX *wctx = (PROV_AES_WRAP_CTX *)vctx;
ctx->enc = enc;
ctx->block = enc ? (block128_f)AES_encrypt : (block128_f)AES_decrypt;
if (ctx->pad)
wctx->wrapfn = enc ? CRYPTO_128_wrap_pad : CRYPTO_128_unwrap_pad;
else
wctx->wrapfn = enc ? CRYPTO_128_wrap : CRYPTO_128_unwrap;
if (iv != NULL) {
if (!cipher_generic_initiv(ctx, iv, ivlen))
return 0;
}
if (key != NULL) {
if (keylen != ctx->keylen) {
ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_KEY_LENGTH);
return 0;
}
if (ctx->enc)
AES_set_encrypt_key(key, keylen * 8, &wctx->ks.ks);
else
AES_set_decrypt_key(key, keylen * 8, &wctx->ks.ks);
}
return 1;
}
static int aes_wrap_einit(void *ctx, const unsigned char *key, size_t keylen,
const unsigned char *iv, size_t ivlen)
{
return aes_wrap_init(ctx, key, keylen, iv, ivlen, 1);
}
static int aes_wrap_dinit(void *ctx, const unsigned char *key, size_t keylen,
const unsigned char *iv, size_t ivlen)
{
return aes_wrap_init(ctx, key, keylen, iv, ivlen, 0);
}
static int aes_wrap_cipher_internal(void *vctx, unsigned char *out,
const unsigned char *in, size_t inlen)
{
PROV_CIPHER_CTX *ctx = (PROV_CIPHER_CTX *)vctx;
PROV_AES_WRAP_CTX *wctx = (PROV_AES_WRAP_CTX *)vctx;
size_t rv;
int pad = ctx->pad;
/* No final operation so always return zero length */
if (in == NULL)
return 0;
/* Input length must always be non-zero */
if (inlen == 0)
return -1;
/* If decrypting need at least 16 bytes and multiple of 8 */
if (!ctx->enc && (inlen < 16 || inlen & 0x7))
return -1;
/* If not padding input must be multiple of 8 */
if (!pad && inlen & 0x7)
return -1;
if (out == NULL) {
if (ctx->enc) {
/* If padding round up to multiple of 8 */
if (pad)
inlen = (inlen + 7) / 8 * 8;
/* 8 byte prefix */
return inlen + 8;
} else {
/*
* If not padding output will be exactly 8 bytes smaller than
* input. If padding it will be at least 8 bytes smaller but we
* don't know how much.
*/
return inlen - 8;
}
}
rv = wctx->wrapfn(&wctx->ks.ks, ctx->iv_set ? ctx->iv : NULL, out, in,
inlen, ctx->block);
return rv ? (int)rv : -1;
}
static int aes_wrap_final(void *vctx, unsigned char *out, size_t *outl,
size_t outsize)
{
*outl = 0;
return 1;
}
static int aes_wrap_cipher(void *vctx,
unsigned char *out, size_t *outl, size_t outsize,
const unsigned char *in, size_t inl)
{
PROV_AES_WRAP_CTX *ctx = (PROV_AES_WRAP_CTX *)vctx;
size_t len;
if (inl == 0) {
*outl = 0;
return 1;
}
if (outsize < inl) {
ERR_raise(ERR_LIB_PROV, PROV_R_OUTPUT_BUFFER_TOO_SMALL);
return -1;
}
len = aes_wrap_cipher_internal(ctx, out, in, inl);
if (len == 0)
return -1;
*outl = len;
return 1;
}
static int aes_wrap_set_ctx_params(void *vctx, const OSSL_PARAM params[])
{
PROV_CIPHER_CTX *ctx = (PROV_CIPHER_CTX *)vctx;
const OSSL_PARAM *p;
size_t keylen = 0;
p = OSSL_PARAM_locate_const(params, OSSL_CIPHER_PARAM_KEYLEN);
if (p != NULL) {
if (!OSSL_PARAM_get_size_t(p, &keylen)) {
ERR_raise(ERR_LIB_PROV, PROV_R_FAILED_TO_GET_PARAMETER);
return 0;
}
if (ctx->keylen != keylen) {
ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_KEY_LENGTH);
return 0;
}
}
return 1;
}
#define IMPLEMENT_cipher(mode, fname, UCMODE, flags, kbits, blkbits, ivbits) \
static OSSL_OP_cipher_get_params_fn aes_##kbits##_##fname##_get_params; \
static int aes_##kbits##_##fname##_get_params(OSSL_PARAM params[]) \
{ \
return cipher_generic_get_params(params, EVP_CIPH_##UCMODE##_MODE, \
flags, kbits, blkbits, ivbits); \
} \
static OSSL_OP_cipher_newctx_fn aes_##kbits##fname##_newctx; \
static void *aes_##kbits##fname##_newctx(void *provctx) \
{ \
return aes_##mode##_newctx(kbits, blkbits, ivbits, \
EVP_CIPH_##UCMODE##_MODE, flags); \
} \
const OSSL_DISPATCH aes##kbits##fname##_functions[] = { \
{ OSSL_FUNC_CIPHER_NEWCTX, \
(void (*)(void))aes_##kbits##fname##_newctx }, \
{ OSSL_FUNC_CIPHER_ENCRYPT_INIT, (void (*)(void))aes_##mode##_einit }, \
{ OSSL_FUNC_CIPHER_DECRYPT_INIT, (void (*)(void))aes_##mode##_dinit }, \
{ OSSL_FUNC_CIPHER_UPDATE, (void (*)(void))aes_##mode##_cipher }, \
{ OSSL_FUNC_CIPHER_FINAL, (void (*)(void))aes_##mode##_final }, \
{ OSSL_FUNC_CIPHER_FREECTX, (void (*)(void))aes_##mode##_freectx }, \
{ OSSL_FUNC_CIPHER_GET_PARAMS, \
(void (*)(void))aes_##kbits##_##fname##_get_params }, \
{ OSSL_FUNC_CIPHER_GETTABLE_PARAMS, \
(void (*)(void))cipher_generic_gettable_params }, \
{ OSSL_FUNC_CIPHER_GET_CTX_PARAMS, \
(void (*)(void))cipher_generic_get_ctx_params }, \
{ OSSL_FUNC_CIPHER_SET_CTX_PARAMS, \
(void (*)(void))aes_wrap_set_ctx_params }, \
{ OSSL_FUNC_CIPHER_GETTABLE_CTX_PARAMS, \
(void (*)(void))cipher_generic_gettable_ctx_params }, \
{ OSSL_FUNC_CIPHER_SETTABLE_CTX_PARAMS, \
(void (*)(void))cipher_generic_settable_ctx_params }, \
{ 0, NULL } \
}
IMPLEMENT_cipher(wrap, wrap, WRAP, WRAP_FLAGS, 256, 64, AES_WRAP_NOPAD_IVLEN * 8);
IMPLEMENT_cipher(wrap, wrap, WRAP, WRAP_FLAGS, 192, 64, AES_WRAP_NOPAD_IVLEN * 8);
IMPLEMENT_cipher(wrap, wrap, WRAP, WRAP_FLAGS, 128, 64, AES_WRAP_NOPAD_IVLEN * 8);
IMPLEMENT_cipher(wrap, wrappad, WRAP, WRAP_FLAGS, 256, 64, AES_WRAP_PAD_IVLEN * 8);
IMPLEMENT_cipher(wrap, wrappad, WRAP, WRAP_FLAGS, 192, 64, AES_WRAP_PAD_IVLEN * 8);
IMPLEMENT_cipher(wrap, wrappad, WRAP, WRAP_FLAGS, 128, 64, AES_WRAP_PAD_IVLEN * 8);