boringssl/crypto/aes/key_wrap.c
David Benjamin 97227dc52d Replace keywrap AEADs with upstream's APIs.
This finally removes the last Android hack. Both Chromium and Android
end up needing this thing (Chromium needs it for WebCrypto but currently
uses the EVP_AEAD version and Android needs it by way of
wpa_supplicant).

On the Android side, the alternative is we finish upstream's
NEED_INTERNAL_AES_WRAP patch, but then it just uses its own key-wrap
implementation. This seems a little silly, considering we have a version
of key-wrap under a different API anyway.

It also doesn't make much sense to leave the EVP_AEAD API around if we
don't want people to use it and Chromium's the only consumer. Remove it
and I'll switch Chromium to the new---er, old--- APIs next roll.

Change-Id: I23a89cda25bddb6ac1033e4cd408165f393d1e6c
Reviewed-on: https://boringssl-review.googlesource.com/11410
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: Adam Langley <agl@google.com>
2016-10-04 01:37:31 +00:00

135 lines
4.3 KiB
C

/* ====================================================================
* Copyright (c) 2001-2011 The OpenSSL Project. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. All advertising materials mentioning features or use of this
* software must display the following acknowledgment:
* "This product includes software developed by the OpenSSL Project
* for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
*
* 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
* endorse or promote products derived from this software without
* prior written permission. For written permission, please contact
* openssl-core@openssl.org.
*
* 5. Products derived from this software may not be called "OpenSSL"
* nor may "OpenSSL" appear in their names without prior written
* permission of the OpenSSL Project.
*
* 6. Redistributions of any form whatsoever must retain the following
* acknowledgment:
* "This product includes software developed by the OpenSSL Project
* for use in the OpenSSL Toolkit (http://www.openssl.org/)"
*
* THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
* EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
* OF THE POSSIBILITY OF SUCH DAMAGE.
* ==================================================================== */
#include <openssl/aes.h>
#include <limits.h>
#include <string.h>
#include <openssl/mem.h>
/* kDefaultIV is the default IV value given in RFC 3394, 2.2.3.1. */
static const uint8_t kDefaultIV[] = {
0xa6, 0xa6, 0xa6, 0xa6, 0xa6, 0xa6, 0xa6, 0xa6,
};
int AES_wrap_key(const AES_KEY *key, const uint8_t *iv, uint8_t *out,
const uint8_t *in, size_t in_len) {
/* See RFC 3394, section 2.2.1. */
if (in_len > INT_MAX - 8 || in_len < 8 || in_len % 8 != 0) {
return -1;
}
if (iv == NULL) {
iv = kDefaultIV;
}
memmove(out + 8, in, in_len);
uint8_t A[AES_BLOCK_SIZE];
memcpy(A, iv, 8);
size_t n = in_len / 8;
for (unsigned j = 0; j < 6; j++) {
for (size_t i = 1; i <= n; i++) {
memcpy(A + 8, out + 8 * i, 8);
AES_encrypt(A, A, key);
uint32_t t = (uint32_t)(n * j + i);
A[7] ^= t & 0xff;
A[6] ^= (t >> 8) & 0xff;
A[5] ^= (t >> 16) & 0xff;
A[4] ^= (t >> 24) & 0xff;
memcpy(out + 8 * i, A + 8, 8);
}
}
memcpy(out, A, 8);
return (int)in_len + 8;
}
int AES_unwrap_key(const AES_KEY *key, const uint8_t *iv, uint8_t *out,
const uint8_t *in, size_t in_len) {
/* See RFC 3394, section 2.2.2. */
if (in_len > INT_MAX || in_len < 16 || in_len % 8 != 0) {
return -1;
}
if (iv == NULL) {
iv = kDefaultIV;
}
uint8_t A[AES_BLOCK_SIZE];
memcpy(A, in, 8);
memmove(out, in + 8, in_len - 8);
size_t n = (in_len / 8) - 1;
for (unsigned j = 5; j < 6; j--) {
for (size_t i = n; i > 0; i--) {
uint32_t t = (uint32_t)(n * j + i);
A[7] ^= t & 0xff;
A[6] ^= (t >> 8) & 0xff;
A[5] ^= (t >> 16) & 0xff;
A[4] ^= (t >> 24) & 0xff;
memcpy(A + 8, out + 8 * (i - 1), 8);
AES_decrypt(A, A, key);
memcpy(out + 8 * (i - 1), A + 8, 8);
}
}
if (CRYPTO_memcmp(A, iv, 8) != 0) {
return -1;
}
return (int)in_len - 8;
}