mirror of
https://github.com/openssl/openssl.git
synced 2024-12-27 06:21:43 +08:00
81cae8ce09
[skip ci] Reviewed-by: Matt Caswell <matt@openssl.org> (Merged from https://github.com/openssl/openssl/pull/7803)
332 lines
12 KiB
C
332 lines
12 KiB
C
/*
|
|
* Copyright 2013-2018 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
|
|
*/
|
|
|
|
/** Beware!
|
|
*
|
|
* Following wrapping modes were designed for AES but this implementation
|
|
* allows you to use them for any 128 bit block cipher.
|
|
*/
|
|
|
|
#include "internal/cryptlib.h"
|
|
#include <openssl/modes.h>
|
|
|
|
/** RFC 3394 section 2.2.3.1 Default Initial Value */
|
|
static const unsigned char default_iv[] = {
|
|
0xA6, 0xA6, 0xA6, 0xA6, 0xA6, 0xA6, 0xA6, 0xA6,
|
|
};
|
|
|
|
/** RFC 5649 section 3 Alternative Initial Value 32-bit constant */
|
|
static const unsigned char default_aiv[] = {
|
|
0xA6, 0x59, 0x59, 0xA6
|
|
};
|
|
|
|
/** Input size limit: lower than maximum of standards but far larger than
|
|
* anything that will be used in practice.
|
|
*/
|
|
#define CRYPTO128_WRAP_MAX (1UL << 31)
|
|
|
|
/** Wrapping according to RFC 3394 section 2.2.1.
|
|
*
|
|
* @param[in] key Key value.
|
|
* @param[in] iv IV value. Length = 8 bytes. NULL = use default_iv.
|
|
* @param[in] in Plaintext as n 64-bit blocks, n >= 2.
|
|
* @param[in] inlen Length of in.
|
|
* @param[out] out Ciphertext. Minimal buffer length = (inlen + 8) bytes.
|
|
* Input and output buffers can overlap if block function
|
|
* supports that.
|
|
* @param[in] block Block processing function.
|
|
* @return 0 if inlen does not consist of n 64-bit blocks, n >= 2.
|
|
* or if inlen > CRYPTO128_WRAP_MAX.
|
|
* Output length if wrapping succeeded.
|
|
*/
|
|
size_t CRYPTO_128_wrap(void *key, const unsigned char *iv,
|
|
unsigned char *out,
|
|
const unsigned char *in, size_t inlen,
|
|
block128_f block)
|
|
{
|
|
unsigned char *A, B[16], *R;
|
|
size_t i, j, t;
|
|
if ((inlen & 0x7) || (inlen < 16) || (inlen > CRYPTO128_WRAP_MAX))
|
|
return 0;
|
|
A = B;
|
|
t = 1;
|
|
memmove(out + 8, in, inlen);
|
|
if (!iv)
|
|
iv = default_iv;
|
|
|
|
memcpy(A, iv, 8);
|
|
|
|
for (j = 0; j < 6; j++) {
|
|
R = out + 8;
|
|
for (i = 0; i < inlen; i += 8, t++, R += 8) {
|
|
memcpy(B + 8, R, 8);
|
|
block(B, B, key);
|
|
A[7] ^= (unsigned char)(t & 0xff);
|
|
if (t > 0xff) {
|
|
A[6] ^= (unsigned char)((t >> 8) & 0xff);
|
|
A[5] ^= (unsigned char)((t >> 16) & 0xff);
|
|
A[4] ^= (unsigned char)((t >> 24) & 0xff);
|
|
}
|
|
memcpy(R, B + 8, 8);
|
|
}
|
|
}
|
|
memcpy(out, A, 8);
|
|
return inlen + 8;
|
|
}
|
|
|
|
/** Unwrapping according to RFC 3394 section 2.2.2 steps 1-2.
|
|
* The IV check (step 3) is responsibility of the caller.
|
|
*
|
|
* @param[in] key Key value.
|
|
* @param[out] iv Unchecked IV value. Minimal buffer length = 8 bytes.
|
|
* @param[out] out Plaintext without IV.
|
|
* Minimal buffer length = (inlen - 8) bytes.
|
|
* Input and output buffers can overlap if block function
|
|
* supports that.
|
|
* @param[in] in Ciphertext as n 64-bit blocks.
|
|
* @param[in] inlen Length of in.
|
|
* @param[in] block Block processing function.
|
|
* @return 0 if inlen is out of range [24, CRYPTO128_WRAP_MAX]
|
|
* or if inlen is not a multiple of 8.
|
|
* Output length otherwise.
|
|
*/
|
|
static size_t crypto_128_unwrap_raw(void *key, unsigned char *iv,
|
|
unsigned char *out,
|
|
const unsigned char *in, size_t inlen,
|
|
block128_f block)
|
|
{
|
|
unsigned char *A, B[16], *R;
|
|
size_t i, j, t;
|
|
inlen -= 8;
|
|
if ((inlen & 0x7) || (inlen < 16) || (inlen > CRYPTO128_WRAP_MAX))
|
|
return 0;
|
|
A = B;
|
|
t = 6 * (inlen >> 3);
|
|
memcpy(A, in, 8);
|
|
memmove(out, in + 8, inlen);
|
|
for (j = 0; j < 6; j++) {
|
|
R = out + inlen - 8;
|
|
for (i = 0; i < inlen; i += 8, t--, R -= 8) {
|
|
A[7] ^= (unsigned char)(t & 0xff);
|
|
if (t > 0xff) {
|
|
A[6] ^= (unsigned char)((t >> 8) & 0xff);
|
|
A[5] ^= (unsigned char)((t >> 16) & 0xff);
|
|
A[4] ^= (unsigned char)((t >> 24) & 0xff);
|
|
}
|
|
memcpy(B + 8, R, 8);
|
|
block(B, B, key);
|
|
memcpy(R, B + 8, 8);
|
|
}
|
|
}
|
|
memcpy(iv, A, 8);
|
|
return inlen;
|
|
}
|
|
|
|
/** Unwrapping according to RFC 3394 section 2.2.2, including the IV check.
|
|
* The first block of plaintext has to match the supplied IV, otherwise an
|
|
* error is returned.
|
|
*
|
|
* @param[in] key Key value.
|
|
* @param[out] iv IV value to match against. Length = 8 bytes.
|
|
* NULL = use default_iv.
|
|
* @param[out] out Plaintext without IV.
|
|
* Minimal buffer length = (inlen - 8) bytes.
|
|
* Input and output buffers can overlap if block function
|
|
* supports that.
|
|
* @param[in] in Ciphertext as n 64-bit blocks.
|
|
* @param[in] inlen Length of in.
|
|
* @param[in] block Block processing function.
|
|
* @return 0 if inlen is out of range [24, CRYPTO128_WRAP_MAX]
|
|
* or if inlen is not a multiple of 8
|
|
* or if IV doesn't match expected value.
|
|
* Output length otherwise.
|
|
*/
|
|
size_t CRYPTO_128_unwrap(void *key, const unsigned char *iv,
|
|
unsigned char *out, const unsigned char *in,
|
|
size_t inlen, block128_f block)
|
|
{
|
|
size_t ret;
|
|
unsigned char got_iv[8];
|
|
|
|
ret = crypto_128_unwrap_raw(key, got_iv, out, in, inlen, block);
|
|
if (ret == 0)
|
|
return 0;
|
|
|
|
if (!iv)
|
|
iv = default_iv;
|
|
if (CRYPTO_memcmp(got_iv, iv, 8)) {
|
|
OPENSSL_cleanse(out, ret);
|
|
return 0;
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
/** Wrapping according to RFC 5649 section 4.1.
|
|
*
|
|
* @param[in] key Key value.
|
|
* @param[in] icv (Non-standard) IV, 4 bytes. NULL = use default_aiv.
|
|
* @param[out] out Ciphertext. Minimal buffer length = (inlen + 15) bytes.
|
|
* Input and output buffers can overlap if block function
|
|
* supports that.
|
|
* @param[in] in Plaintext as n 64-bit blocks, n >= 2.
|
|
* @param[in] inlen Length of in.
|
|
* @param[in] block Block processing function.
|
|
* @return 0 if inlen is out of range [1, CRYPTO128_WRAP_MAX].
|
|
* Output length if wrapping succeeded.
|
|
*/
|
|
size_t CRYPTO_128_wrap_pad(void *key, const unsigned char *icv,
|
|
unsigned char *out,
|
|
const unsigned char *in, size_t inlen,
|
|
block128_f block)
|
|
{
|
|
/* n: number of 64-bit blocks in the padded key data
|
|
*
|
|
* If length of plain text is not a multiple of 8, pad the plain text octet
|
|
* string on the right with octets of zeros, where final length is the
|
|
* smallest multiple of 8 that is greater than length of plain text.
|
|
* If length of plain text is a multiple of 8, then there is no padding. */
|
|
const size_t blocks_padded = (inlen + 7) / 8; /* CEILING(m/8) */
|
|
const size_t padded_len = blocks_padded * 8;
|
|
const size_t padding_len = padded_len - inlen;
|
|
/* RFC 5649 section 3: Alternative Initial Value */
|
|
unsigned char aiv[8];
|
|
int ret;
|
|
|
|
/* Section 1: use 32-bit fixed field for plaintext octet length */
|
|
if (inlen == 0 || inlen >= CRYPTO128_WRAP_MAX)
|
|
return 0;
|
|
|
|
/* Section 3: Alternative Initial Value */
|
|
if (!icv)
|
|
memcpy(aiv, default_aiv, 4);
|
|
else
|
|
memcpy(aiv, icv, 4); /* Standard doesn't mention this. */
|
|
|
|
aiv[4] = (inlen >> 24) & 0xFF;
|
|
aiv[5] = (inlen >> 16) & 0xFF;
|
|
aiv[6] = (inlen >> 8) & 0xFF;
|
|
aiv[7] = inlen & 0xFF;
|
|
|
|
if (padded_len == 8) {
|
|
/*
|
|
* Section 4.1 - special case in step 2: If the padded plaintext
|
|
* contains exactly eight octets, then prepend the AIV and encrypt
|
|
* the resulting 128-bit block using AES in ECB mode.
|
|
*/
|
|
memmove(out + 8, in, inlen);
|
|
memcpy(out, aiv, 8);
|
|
memset(out + 8 + inlen, 0, padding_len);
|
|
block(out, out, key);
|
|
ret = 16; /* AIV + padded input */
|
|
} else {
|
|
memmove(out, in, inlen);
|
|
memset(out + inlen, 0, padding_len); /* Section 4.1 step 1 */
|
|
ret = CRYPTO_128_wrap(key, aiv, out, out, padded_len, block);
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
/** Unwrapping according to RFC 5649 section 4.2.
|
|
*
|
|
* @param[in] key Key value.
|
|
* @param[in] icv (Non-standard) IV, 4 bytes. NULL = use default_aiv.
|
|
* @param[out] out Plaintext. Minimal buffer length = (inlen - 8) bytes.
|
|
* Input and output buffers can overlap if block function
|
|
* supports that.
|
|
* @param[in] in Ciphertext as n 64-bit blocks.
|
|
* @param[in] inlen Length of in.
|
|
* @param[in] block Block processing function.
|
|
* @return 0 if inlen is out of range [16, CRYPTO128_WRAP_MAX],
|
|
* or if inlen is not a multiple of 8
|
|
* or if IV and message length indicator doesn't match.
|
|
* Output length if unwrapping succeeded and IV matches.
|
|
*/
|
|
size_t CRYPTO_128_unwrap_pad(void *key, const unsigned char *icv,
|
|
unsigned char *out,
|
|
const unsigned char *in, size_t inlen,
|
|
block128_f block)
|
|
{
|
|
/* n: number of 64-bit blocks in the padded key data */
|
|
size_t n = inlen / 8 - 1;
|
|
size_t padded_len;
|
|
size_t padding_len;
|
|
size_t ptext_len;
|
|
/* RFC 5649 section 3: Alternative Initial Value */
|
|
unsigned char aiv[8];
|
|
static unsigned char zeros[8] = { 0x0 };
|
|
size_t ret;
|
|
|
|
/* Section 4.2: Ciphertext length has to be (n+1) 64-bit blocks. */
|
|
if ((inlen & 0x7) != 0 || inlen < 16 || inlen >= CRYPTO128_WRAP_MAX)
|
|
return 0;
|
|
|
|
if (inlen == 16) {
|
|
/*
|
|
* Section 4.2 - special case in step 1: When n=1, the ciphertext
|
|
* contains exactly two 64-bit blocks and they are decrypted as a
|
|
* single AES block using AES in ECB mode: AIV | P[1] = DEC(K, C[0] |
|
|
* C[1])
|
|
*/
|
|
unsigned char buff[16];
|
|
|
|
block(in, buff, key);
|
|
memcpy(aiv, buff, 8);
|
|
/* Remove AIV */
|
|
memcpy(out, buff + 8, 8);
|
|
padded_len = 8;
|
|
OPENSSL_cleanse(buff, inlen);
|
|
} else {
|
|
padded_len = inlen - 8;
|
|
ret = crypto_128_unwrap_raw(key, aiv, out, in, inlen, block);
|
|
if (padded_len != ret) {
|
|
OPENSSL_cleanse(out, inlen);
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Section 3: AIV checks: Check that MSB(32,A) = A65959A6. Optionally a
|
|
* user-supplied value can be used (even if standard doesn't mention
|
|
* this).
|
|
*/
|
|
if ((!icv && CRYPTO_memcmp(aiv, default_aiv, 4))
|
|
|| (icv && CRYPTO_memcmp(aiv, icv, 4))) {
|
|
OPENSSL_cleanse(out, inlen);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Check that 8*(n-1) < LSB(32,AIV) <= 8*n. If so, let ptext_len =
|
|
* LSB(32,AIV).
|
|
*/
|
|
|
|
ptext_len = ((unsigned int)aiv[4] << 24)
|
|
| ((unsigned int)aiv[5] << 16)
|
|
| ((unsigned int)aiv[6] << 8)
|
|
| (unsigned int)aiv[7];
|
|
if (8 * (n - 1) >= ptext_len || ptext_len > 8 * n) {
|
|
OPENSSL_cleanse(out, inlen);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Check that the rightmost padding_len octets of the output data are
|
|
* zero.
|
|
*/
|
|
padding_len = padded_len - ptext_len;
|
|
if (CRYPTO_memcmp(out + ptext_len, zeros, padding_len) != 0) {
|
|
OPENSSL_cleanse(out, inlen);
|
|
return 0;
|
|
}
|
|
|
|
/* Section 4.2 step 3: Remove padding */
|
|
return ptext_len;
|
|
}
|