/*
* AES Key Wrap Algorithm (128-bit KEK) (RFC3394)
* One-Key CBC MAC (OMAC1) hash with AES-128
* AES-128 CTR mode encryption
* AES-128 EAX mode encryption/decryption
* AES-128 CBC
* Copyright (c) 2003-2004, Jouni Malinen <jkmaline@cc.hut.fi>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* Alternatively, this software may be distributed under the terms of BSD
* license.
*
* See README and COPYING for more details.
*/
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include "common.h"
#include "aes_wrap.h"
#ifdef EAP_TLS_FUNCS
#include <openssl/aes.h>
#else /* EAP_TLS_FUNCS */
#include "aes.c"
struct aes_key_st {
u32 rk[44];
};
typedef struct aes_key_st AES_KEY;
#define AES_set_encrypt_key(userKey, bits, key) \
rijndaelKeySetupEnc((key)->rk, (userKey))
#define AES_set_decrypt_key(userKey, bits, key) \
rijndaelKeySetupDec((key)->rk, (userKey))
#define AES_encrypt(in, out, key) \
rijndaelEncrypt((key)->rk, in, out)
#define AES_decrypt(in, out, key) \
rijndaelDecrypt((key)->rk, in, out)
#endif /* EAP_TLS_FUNCS */
/*
* @kek: key encryption key (KEK)
* @n: length of the wrapped key in 64-bit units; e.g., 2 = 128-bit = 16 bytes
* @plain: plaintext key to be wrapped, n * 64 bit
* @cipher: wrapped key, (n + 1) * 64 bit
*/
void aes_wrap(u8 *kek, int n, u8 *plain, u8 *cipher)
{
u8 *a, *r, b[16];
int i, j;
AES_KEY key;
a = cipher;
r = cipher + 8;
/* 1) Initialize variables. */
memset(a, 0xa6, 8);
memcpy(r, plain, 8 * n);
AES_set_encrypt_key(kek, 128, &key);
/* 2) Calculate intermediate values.
* For j = 0 to 5
* For i=1 to n
* B = AES(K, A | R[i])
* A = MSB(64, B) ^ t where t = (n*j)+i
* R[i] = LSB(64, B)
*/
for (j = 0; j <= 5; j++) {
r = cipher + 8;
for (i = 1; i <= n; i++) {
memcpy(b, a, 8);
memcpy(b + 8, r, 8);
AES_encrypt(b, b, &key);
memcpy(a, b, 8);
a[7] ^= n * j + i;
memcpy(r, b + 8, 8);
r += 8;
}
}
/* 3) Output the results.
*
* These are already in @cipher due to the location of temporary
* variables.
*/
}
/*
* @kek: key encryption key (KEK)
* @n: length of the wrapped key in 64-bit units; e.g., 2 = 128-bit = 16 bytes
* @cipher: wrapped key to be unwrapped, (n + 1) * 64 bit
* @plain: plaintext key, n * 64 bit
*/
int aes_unwrap(u8 *kek, int n, u8 *cipher, u8 *plain)
{
u8 a[8], *r, b[16];
int i, j;
AES_KEY key;
/* 1) Initialize variables. */
memcpy(a, cipher, 8);
r = plain;
memcpy(r, cipher + 8, 8 * n);
AES_set_decrypt_key(kek, 128, &key);
/* 2) Compute intermediate values.
* For j = 5 to 0
* For i = n to 1
* B = AES-1(K, (A ^ t) | R[i]) where t = n*j+i
* A = MSB(64, B)
* R[i] = LSB(64, B)
*/
for (j = 5; j >= 0; j--) {
r = plain + (n - 1) * 8;
for (i = n; i >= 1; i--) {
memcpy(b, a, 8);
b[7] ^= n * j + i;
memcpy(b + 8, r, 8);
AES_decrypt(b, b, &key);
memcpy(a, b, 8);
memcpy(r, b + 8, 8);
r -= 8;
}
}
/* 3) Output results.
*
* These are already in @plain due to the location of temporary
* variables. Just verify that the IV matches with the expected value.
*/
for (i = 0; i < 8; i++) {
if (a[i] != 0xa6)
return -1;
}
return 0;
}
#define BLOCK_SIZE 16
static void gf_mulx(u8 *pad)
{
int i, carry;
carry = pad[0] & 0x80;
for (i = 0; i < BLOCK_SIZE - 1; i++)
pad[i] = (pad[i] << 1) | (pad[i + 1] >> 7);
pad[BLOCK_SIZE - 1] <<= 1;
if (carry)
pad[BLOCK_SIZE - 1] ^= 0x87;
}
void omac1_aes_128(const u8 *key, const u8 *data, size_t data_len, u8 *mac)
{
AES_KEY akey;
u8 cbc[BLOCK_SIZE], pad[BLOCK_SIZE];
const u8 *pos = data;
int i;
size_t left = data_len;
AES_set_encrypt_key(key, 128, &akey);
memset(cbc, 0, BLOCK_SIZE);
while (left >= BLOCK_SIZE) {
for (i = 0; i < BLOCK_SIZE; i++)
cbc[i] ^= *pos++;
if (left > BLOCK_SIZE)
AES_encrypt(cbc, cbc, &akey);
left -= BLOCK_SIZE;
}
memset(pad, 0, BLOCK_SIZE);
AES_encrypt(pad, pad, &akey);
gf_mulx(pad);
if (left || data_len == 0) {
for (i = 0; i < left; i++)
cbc[i] ^= *pos++;
cbc[left] ^= 0x80;
gf_mulx(pad);
}
for (i = 0; i < BLOCK_SIZE; i++)
pad[i] ^= cbc[i];
AES_encrypt(pad, mac, &akey);
}
void aes_128_encrypt_block(const u8 *key, const u8 *in, u8 *out)
{
AES_KEY akey;
AES_set_encrypt_key(key, 128, &akey);
AES_encrypt(in, out, &akey);
}
void aes_128_ctr_encrypt(const u8 *key, const u8 *nonce,
u8 *data, size_t data_len)
{
AES_KEY akey;
size_t len, left = data_len;
int i;
u8 *pos = data;
u8 counter[BLOCK_SIZE], buf[BLOCK_SIZE];
AES_set_encrypt_key(key, 128, &akey);
memcpy(counter, nonce, BLOCK_SIZE);
while (left > 0) {
AES_encrypt(counter, buf, &akey);
len = (left < BLOCK_SIZE) ? left : BLOCK_SIZE;
for (i = 0; i < len; i++)
pos[i] ^= buf[i];
pos += len;
left -= len;
for (i = BLOCK_SIZE - 1; i >= 0; i--) {
counter[i]++;
if (counter[i])
break;
}
}
}
int aes_128_eax_encrypt(const u8 *key, const u8 *nonce, size_t nonce_len,
const u8 *hdr, size_t hdr_len,
u8 *data, size_t data_len, u8 *tag)
{
u8 *buf;
size_t buf_len;
u8 nonce_mac[BLOCK_SIZE], hdr_mac[BLOCK_SIZE], data_mac[BLOCK_SIZE];
int i;
if (nonce_len > data_len)
buf_len = nonce_len;
else
buf_len = data_len;
if (hdr_len > buf_len)
buf_len = hdr_len;
buf_len += 16;
buf = malloc(buf_len);
if (buf == NULL)
return -1;
memset(buf, 0, 15);
buf[15] = 0;
memcpy(buf + 16, nonce, nonce_len);
omac1_aes_128(key, buf, 16 + nonce_len, nonce_mac);
buf[15] = 1;
memcpy(buf + 16, hdr, hdr_len);
omac1_aes_128(key, buf, 16 + hdr_len, hdr_mac);
aes_128_ctr_encrypt(key, nonce_mac, data, data_len);
buf[15] = 2;
memcpy(buf + 16, data, data_len);
omac1_aes_128(key, buf, 16 + data_len, data_mac);
free(buf);
for (i = 0; i < BLOCK_SIZE; i++)
tag[i] = nonce_mac[i] ^ data_mac[i] ^ hdr_mac[i];
return 0;
}
int aes_128_eax_decrypt(const u8 *key, const u8 *nonce, size_t nonce_len,
const u8 *hdr, size_t hdr_len,
u8 *data, size_t data_len, const u8 *tag)
{
u8 *buf;
size_t buf_len;
u8 nonce_mac[BLOCK_SIZE], hdr_mac[BLOCK_SIZE], data_mac[BLOCK_SIZE];
int i;
if (nonce_len > data_len)
buf_len = nonce_len;
else
buf_len = data_len;
if (hdr_len > buf_len)
buf_len = hdr_len;
buf_len += 16;
buf = malloc(buf_len);
if (buf == NULL)
return -1;
memset(buf, 0, 15);
buf[15] = 0;
memcpy(buf + 16, nonce, nonce_len);
omac1_aes_128(key, buf, 16 + nonce_len, nonce_mac);
buf[15] = 1;
memcpy(buf + 16, hdr, hdr_len);
omac1_aes_128(key, buf, 16 + hdr_len, hdr_mac);
buf[15] = 2;
memcpy(buf + 16, data, data_len);
omac1_aes_128(key, buf, 16 + data_len, data_mac);
free(buf);
for (i = 0; i < BLOCK_SIZE; i++) {
if (tag[i] != (nonce_mac[i] ^ data_mac[i] ^ hdr_mac[i]))
return -2;
}
aes_128_ctr_encrypt(key, nonce_mac, data, data_len);
return 0;
}
void aes_128_cbc_encrypt(const u8 *key, const u8 *iv, u8 *data,
size_t data_len)
{
AES_KEY akey;
u8 cbc[BLOCK_SIZE];
u8 *pos = data;
int i, j, blocks;
AES_set_encrypt_key(key, 128, &akey);
memcpy(cbc, iv, BLOCK_SIZE);
blocks = data_len / BLOCK_SIZE;
for (i = 0; i < blocks; i++) {
for (j = 0; j < BLOCK_SIZE; j++)
cbc[j] ^= pos[j];
AES_encrypt(cbc, cbc, &akey);
memcpy(pos, cbc, BLOCK_SIZE);
pos += BLOCK_SIZE;
}
}
void aes_128_cbc_decrypt(const u8 *key, const u8 *iv, u8 *data,
size_t data_len)
{
AES_KEY akey;
u8 cbc[BLOCK_SIZE], tmp[BLOCK_SIZE];
u8 *pos = data;
int i, j, blocks;
AES_set_decrypt_key(key, 128, &akey);
memcpy(cbc, iv, BLOCK_SIZE);
blocks = data_len / BLOCK_SIZE;
for (i = 0; i < blocks; i++) {
memcpy(tmp, pos, BLOCK_SIZE);
AES_decrypt(pos, pos, &akey);
for (j = 0; j < BLOCK_SIZE; j++)
pos[j] ^= cbc[j];
memcpy(cbc, tmp, BLOCK_SIZE);
pos += BLOCK_SIZE;
}
}
#ifdef TEST_MAIN
#ifdef __i386__
#define rdtscll(val) \
__asm__ __volatile__("rdtsc" : "=A" (val))
static void test_aes_perf(void)
{
const int num_iters = 10;
int i;
unsigned int start, end;
AES_KEY akey;
u8 key[16], pt[16], ct[16];
printf("keySetupEnc:");
for (i = 0; i < num_iters; i++) {
rdtscll(start);
AES_set_encrypt_key(key, 128, &akey);
rdtscll(end);
printf(" %d", end - start);
}
printf("\n");
printf("Encrypt:");
for (i = 0; i < num_iters; i++) {
rdtscll(start);
AES_encrypt(pt, ct, &akey);
rdtscll(end);
printf(" %d", end - start);
}
printf("\n");
}
#endif /* __i386__ */
static int test_eax(void)
{
u8 msg[] = { 0xF7, 0xFB };
u8 key[] = { 0x91, 0x94, 0x5D, 0x3F, 0x4D, 0xCB, 0xEE, 0x0B,
0xF4, 0x5E, 0xF5, 0x22, 0x55, 0xF0, 0x95, 0xA4 };
u8 nonce[] = { 0xBE, 0xCA, 0xF0, 0x43, 0xB0, 0xA2, 0x3D, 0x84,
0x31, 0x94, 0xBA, 0x97, 0x2C, 0x66, 0xDE, 0xBD };
u8 hdr[] = { 0xFA, 0x3B, 0xFD, 0x48, 0x06, 0xEB, 0x53, 0xFA };
u8 cipher[] = { 0x19, 0xDD, 0x5C, 0x4C, 0x93, 0x31, 0x04, 0x9D,
0x0B, 0xDA, 0xB0, 0x27, 0x74, 0x08, 0xF6, 0x79,
0x67, 0xE5 };
u8 data[sizeof(msg)], tag[BLOCK_SIZE];
memcpy(data, msg, sizeof(msg));
if (aes_128_eax_encrypt(key, nonce, sizeof(nonce), hdr, sizeof(hdr),
data, sizeof(data), tag)) {
printf("AES-128 EAX mode encryption failed\n");
return 1;
}
if (memcmp(data, cipher, sizeof(data)) != 0) {
printf("AES-128 EAX mode encryption returned invalid cipher "
"text\n");
return 1;
}
if (memcmp(tag, cipher + sizeof(data), BLOCK_SIZE) != 0) {
printf("AES-128 EAX mode encryption returned invalid tag\n");
return 1;
}
if (aes_128_eax_decrypt(key, nonce, sizeof(nonce), hdr, sizeof(hdr),
data, sizeof(data), tag)) {
printf("AES-128 EAX mode decryption failed\n");
return 1;
}
if (memcmp(data, msg, sizeof(data)) != 0) {
printf("AES-128 EAX mode decryption returned invalid plain "
"text\n");
return 1;
}
return 0;
}
static int test_cbc(void)
{
struct cbc_test_vector {
u8 key[16];
u8 iv[16];
u8 plain[32];
u8 cipher[32];
size_t len;
} vectors[] = {
{
{ 0x06, 0xa9, 0x21, 0x40, 0x36, 0xb8, 0xa1, 0x5b,
0x51, 0x2e, 0x03, 0xd5, 0x34, 0x12, 0x00, 0x06 },
{ 0x3d, 0xaf, 0xba, 0x42, 0x9d, 0x9e, 0xb4, 0x30,
0xb4, 0x22, 0xda, 0x80, 0x2c, 0x9f, 0xac, 0x41 },
"Single block msg",
{ 0xe3, 0x53, 0x77, 0x9c, 0x10, 0x79, 0xae, 0xb8,
0x27, 0x08, 0x94, 0x2d, 0xbe, 0x77, 0x18, 0x1a },
16
},
{
{ 0xc2, 0x86, 0x69, 0x6d, 0x88, 0x7c, 0x9a, 0xa0,
0x61, 0x1b, 0xbb, 0x3e, 0x20, 0x25, 0xa4, 0x5a },
{ 0x56, 0x2e, 0x17, 0x99, 0x6d, 0x09, 0x3d, 0x28,
0xdd, 0xb3, 0xba, 0x69, 0x5a, 0x2e, 0x6f, 0x58 },
{ 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f },
{ 0xd2, 0x96, 0xcd, 0x94, 0xc2, 0xcc, 0xcf, 0x8a,
0x3a, 0x86, 0x30, 0x28, 0xb5, 0xe1, 0xdc, 0x0a,
0x75, 0x86, 0x60, 0x2d, 0x25, 0x3c, 0xff, 0xf9,
0x1b, 0x82, 0x66, 0xbe, 0xa6, 0xd6, 0x1a, 0xb1 },
32
}
};
int i, ret = 0;
u8 *buf;
for (i = 0; i < sizeof(vectors) / sizeof(vectors[0]); i++) {
struct cbc_test_vector *tv = &vectors[i];
buf = malloc(tv->len);
if (buf == NULL) {
ret++;
break;
}
memcpy(buf, tv->plain, tv->len);
aes_128_cbc_encrypt(tv->key, tv->iv, buf, tv->len);
if (memcmp(buf, tv->cipher, tv->len) != 0) {
printf("AES-CBC encrypt %d failed\n", i);
ret++;
}
memcpy(buf, tv->cipher, tv->len);
aes_128_cbc_decrypt(tv->key, tv->iv, buf, tv->len);
if (memcmp(buf, tv->plain, tv->len) != 0) {
printf("AES-CBC decrypt %d failed\n", i);
ret++;
}
free(buf);
}
return ret;
}
/* OMAC1 AES-128 test vectors from
* http://csrc.nist.gov/CryptoToolkit/modes/proposedmodes/omac/omac-ad.pdf
*/
struct omac1_test_vector {
u8 k[16];
u8 msg[64];
int msg_len;
u8 tag[16];
};
static struct omac1_test_vector test_vectors[] =
{
{
{ 0x2b, 0x7e, 0x15, 0x16, 0x28, 0xae, 0xd2, 0xa6,
0xab, 0xf7, 0x15, 0x88, 0x09, 0xcf, 0x4f, 0x3c },
{ },
0,
{ 0xbb, 0x1d, 0x69, 0x29, 0xe9, 0x59, 0x37, 0x28,
0x7f, 0xa3, 0x7d, 0x12, 0x9b, 0x75, 0x67, 0x46 }
},
{
{ 0x2b, 0x7e, 0x15, 0x16, 0x28, 0xae, 0xd2, 0xa6,
0xab, 0xf7, 0x15, 0x88, 0x09, 0xcf, 0x4f, 0x3c },
{ 0x6b, 0xc1, 0xbe, 0xe2, 0x2e, 0x40, 0x9f, 0x96,
0xe9, 0x3d, 0x7e, 0x11, 0x73, 0x93, 0x17, 0x2a},
16,
{ 0x07, 0x0a, 0x16, 0xb4, 0x6b, 0x4d, 0x41, 0x44,
0xf7, 0x9b, 0xdd, 0x9d, 0xd0, 0x4a, 0x28, 0x7c }
},
{
{ 0x2b, 0x7e, 0x15, 0x16, 0x28, 0xae, 0xd2, 0xa6,
0xab, 0xf7, 0x15, 0x88, 0x09, 0xcf, 0x4f, 0x3c },
{ 0x6b, 0xc1, 0xbe, 0xe2, 0x2e, 0x40, 0x9f, 0x96,
0xe9, 0x3d, 0x7e, 0x11, 0x73, 0x93, 0x17, 0x2a,
0xae, 0x2d, 0x8a, 0x57, 0x1e, 0x03, 0xac, 0x9c,
0x9e, 0xb7, 0x6f, 0xac, 0x45, 0xaf, 0x8e, 0x51,
0x30, 0xc8, 0x1c, 0x46, 0xa3, 0x5c, 0xe4, 0x11 },
40,
{ 0xdf, 0xa6, 0x67, 0x47, 0xde, 0x9a, 0xe6, 0x30,
0x30, 0xca, 0x32, 0x61, 0x14, 0x97, 0xc8, 0x27 }
},
{
{ 0x2b, 0x7e, 0x15, 0x16, 0x28, 0xae, 0xd2, 0xa6,
0xab, 0xf7, 0x15, 0x88, 0x09, 0xcf, 0x4f, 0x3c },
{ 0x6b, 0xc1, 0xbe, 0xe2, 0x2e, 0x40, 0x9f, 0x96,
0xe9, 0x3d, 0x7e, 0x11, 0x73, 0x93, 0x17, 0x2a,
0xae, 0x2d, 0x8a, 0x57, 0x1e, 0x03, 0xac, 0x9c,
0x9e, 0xb7, 0x6f, 0xac, 0x45, 0xaf, 0x8e, 0x51,
0x30, 0xc8, 0x1c, 0x46, 0xa3, 0x5c, 0xe4, 0x11,
0xe5, 0xfb, 0xc1, 0x19, 0x1a, 0x0a, 0x52, 0xef,
0xf6, 0x9f, 0x24, 0x45, 0xdf, 0x4f, 0x9b, 0x17,
0xad, 0x2b, 0x41, 0x7b, 0xe6, 0x6c, 0x37, 0x10 },
64,
{ 0x51, 0xf0, 0xbe, 0xbf, 0x7e, 0x3b, 0x9d, 0x92,
0xfc, 0x49, 0x74, 0x17, 0x79, 0x36, 0x3c, 0xfe }
},
};
int main(int argc, char *argv[])
{
u8 kek[] = {
0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f
};
u8 plain[] = {
0x00, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77,
0x88, 0x99, 0xaa, 0xbb, 0xcc, 0xdd, 0xee, 0xff
};
u8 crypt[] = {
0x1F, 0xA6, 0x8B, 0x0A, 0x81, 0x12, 0xB4, 0x47,
0xAE, 0xF3, 0x4B, 0xD8, 0xFB, 0x5A, 0x7B, 0x82,
0x9D, 0x3E, 0x86, 0x23, 0x71, 0xD2, 0xCF, 0xE5
};
u8 result[24];
int ret = 0, i;
struct omac1_test_vector *tv;
aes_wrap(kek, 2, plain, result);
if (memcmp(result, crypt, 24) != 0) {
printf("AES-WRAP-128-128 failed\n");
ret++;
}
if (aes_unwrap(kek, 2, crypt, result)) {
printf("AES-UNWRAP-128-128 reported failure\n");
ret++;
}
if (memcmp(result, plain, 16) != 0) {
int i;
printf("AES-UNWRAP-128-128 failed\n");
ret++;
for (i = 0; i < 16; i++)
printf(" %02x", result[i]);
printf("\n");
}
#ifdef __i386__
test_aes_perf();
#endif /* __i386__ */
for (i = 0; i < sizeof(test_vectors) / sizeof(test_vectors[0]); i++) {
tv = &test_vectors[i];
omac1_aes_128(tv->k, tv->msg, tv->msg_len, result);
if (memcmp(result, tv->tag, 16) != 0) {
printf("OMAC1-AES-128 test vector %d failed\n", i);
ret++;
}
}
ret += test_eax();
ret += test_cbc();
if (ret)
printf("FAILED!\n");
return ret;
}
#endif /* TEST_MAIN */
