freebsd-skq/contrib/wpa_supplicant/crypto_internal.c
2007-07-11 15:48:36 +00:00

671 lines
14 KiB
C

/*
* WPA Supplicant / Crypto wrapper for internal crypto implementation
* Copyright (c) 2006, Jouni Malinen <j@w1.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 "includes.h"
#include "common.h"
#include "crypto.h"
#include "md5.h"
#include "sha1.h"
#include "rc4.h"
#include "aes.h"
#include "rsa.h"
#include "bignum.h"
#ifdef EAP_TLS_FUNCS
#ifdef CONFIG_TLS_INTERNAL
/* from des.c */
struct des3_key_s {
u32 ek[3][32];
u32 dk[3][32];
};
void des3_key_setup(const u8 *key, struct des3_key_s *dkey);
void des3_encrypt(const u8 *plain, const struct des3_key_s *key, u8 *crypt);
void des3_decrypt(const u8 *crypt, const struct des3_key_s *key, u8 *plain);
struct MD5Context {
u32 buf[4];
u32 bits[2];
u8 in[64];
};
struct SHA1Context {
u32 state[5];
u32 count[2];
unsigned char buffer[64];
};
struct crypto_hash {
enum crypto_hash_alg alg;
union {
struct MD5Context md5;
struct SHA1Context sha1;
} u;
u8 key[64];
size_t key_len;
};
struct crypto_hash * crypto_hash_init(enum crypto_hash_alg alg, const u8 *key,
size_t key_len)
{
struct crypto_hash *ctx;
u8 k_pad[64];
u8 tk[20];
size_t i;
ctx = os_zalloc(sizeof(*ctx));
if (ctx == NULL)
return NULL;
ctx->alg = alg;
switch (alg) {
case CRYPTO_HASH_ALG_MD5:
MD5Init(&ctx->u.md5);
break;
case CRYPTO_HASH_ALG_SHA1:
SHA1Init(&ctx->u.sha1);
break;
case CRYPTO_HASH_ALG_HMAC_MD5:
if (key_len > sizeof(k_pad)) {
MD5Init(&ctx->u.md5);
MD5Update(&ctx->u.md5, key, key_len);
MD5Final(tk, &ctx->u.md5);
key = tk;
key_len = 16;
}
os_memcpy(ctx->key, key, key_len);
ctx->key_len = key_len;
os_memcpy(k_pad, key, key_len);
os_memset(k_pad + key_len, 0, sizeof(k_pad) - key_len);
for (i = 0; i < sizeof(k_pad); i++)
k_pad[i] ^= 0x36;
MD5Init(&ctx->u.md5);
MD5Update(&ctx->u.md5, k_pad, sizeof(k_pad));
break;
case CRYPTO_HASH_ALG_HMAC_SHA1:
if (key_len > sizeof(k_pad)) {
SHA1Init(&ctx->u.sha1);
SHA1Update(&ctx->u.sha1, key, key_len);
SHA1Final(tk, &ctx->u.sha1);
key = tk;
key_len = 20;
}
os_memcpy(ctx->key, key, key_len);
ctx->key_len = key_len;
os_memcpy(k_pad, key, key_len);
os_memset(k_pad + key_len, 0, sizeof(k_pad) - key_len);
for (i = 0; i < sizeof(k_pad); i++)
k_pad[i] ^= 0x36;
SHA1Init(&ctx->u.sha1);
SHA1Update(&ctx->u.sha1, k_pad, sizeof(k_pad));
break;
default:
os_free(ctx);
return NULL;
}
return ctx;
}
void crypto_hash_update(struct crypto_hash *ctx, const u8 *data, size_t len)
{
if (ctx == NULL)
return;
switch (ctx->alg) {
case CRYPTO_HASH_ALG_MD5:
case CRYPTO_HASH_ALG_HMAC_MD5:
MD5Update(&ctx->u.md5, data, len);
break;
case CRYPTO_HASH_ALG_SHA1:
case CRYPTO_HASH_ALG_HMAC_SHA1:
SHA1Update(&ctx->u.sha1, data, len);
break;
}
}
int crypto_hash_finish(struct crypto_hash *ctx, u8 *mac, size_t *len)
{
u8 k_pad[64];
size_t i;
if (ctx == NULL)
return -2;
if (mac == NULL || len == NULL) {
os_free(ctx);
return 0;
}
switch (ctx->alg) {
case CRYPTO_HASH_ALG_MD5:
if (*len < 16) {
*len = 16;
os_free(ctx);
return -1;
}
*len = 16;
MD5Final(mac, &ctx->u.md5);
break;
case CRYPTO_HASH_ALG_SHA1:
if (*len < 20) {
*len = 20;
os_free(ctx);
return -1;
}
*len = 20;
SHA1Final(mac, &ctx->u.sha1);
break;
case CRYPTO_HASH_ALG_HMAC_MD5:
if (*len < 16) {
*len = 16;
os_free(ctx);
return -1;
}
*len = 16;
MD5Final(mac, &ctx->u.md5);
os_memcpy(k_pad, ctx->key, ctx->key_len);
os_memset(k_pad + ctx->key_len, 0,
sizeof(k_pad) - ctx->key_len);
for (i = 0; i < sizeof(k_pad); i++)
k_pad[i] ^= 0x5c;
MD5Init(&ctx->u.md5);
MD5Update(&ctx->u.md5, k_pad, sizeof(k_pad));
MD5Update(&ctx->u.md5, mac, 16);
MD5Final(mac, &ctx->u.md5);
break;
case CRYPTO_HASH_ALG_HMAC_SHA1:
if (*len < 20) {
*len = 20;
os_free(ctx);
return -1;
}
*len = 20;
SHA1Final(mac, &ctx->u.sha1);
os_memcpy(k_pad, ctx->key, ctx->key_len);
os_memset(k_pad + ctx->key_len, 0,
sizeof(k_pad) - ctx->key_len);
for (i = 0; i < sizeof(k_pad); i++)
k_pad[i] ^= 0x5c;
SHA1Init(&ctx->u.sha1);
SHA1Update(&ctx->u.sha1, k_pad, sizeof(k_pad));
SHA1Update(&ctx->u.sha1, mac, 20);
SHA1Final(mac, &ctx->u.sha1);
break;
}
os_free(ctx);
return 0;
}
struct crypto_cipher {
enum crypto_cipher_alg alg;
union {
struct {
size_t used_bytes;
u8 key[16];
size_t keylen;
} rc4;
struct {
u8 cbc[32];
size_t block_size;
void *ctx_enc;
void *ctx_dec;
} aes;
struct {
struct des3_key_s key;
u8 cbc[8];
} des3;
} u;
};
struct crypto_cipher * crypto_cipher_init(enum crypto_cipher_alg alg,
const u8 *iv, const u8 *key,
size_t key_len)
{
struct crypto_cipher *ctx;
ctx = os_zalloc(sizeof(*ctx));
if (ctx == NULL)
return NULL;
ctx->alg = alg;
switch (alg) {
case CRYPTO_CIPHER_ALG_RC4:
if (key_len > sizeof(ctx->u.rc4.key)) {
os_free(ctx);
return NULL;
}
ctx->u.rc4.keylen = key_len;
os_memcpy(ctx->u.rc4.key, key, key_len);
break;
case CRYPTO_CIPHER_ALG_AES:
if (key_len > sizeof(ctx->u.aes.cbc)) {
os_free(ctx);
return NULL;
}
ctx->u.aes.ctx_enc = aes_encrypt_init(key, key_len);
if (ctx->u.aes.ctx_enc == NULL) {
os_free(ctx);
return NULL;
}
ctx->u.aes.ctx_dec = aes_decrypt_init(key, key_len);
if (ctx->u.aes.ctx_dec == NULL) {
aes_encrypt_deinit(ctx->u.aes.ctx_enc);
os_free(ctx);
return NULL;
}
ctx->u.aes.block_size = key_len;
os_memcpy(ctx->u.aes.cbc, iv, ctx->u.aes.block_size);
break;
case CRYPTO_CIPHER_ALG_3DES:
if (key_len != 24) {
os_free(ctx);
return NULL;
}
des3_key_setup(key, &ctx->u.des3.key);
os_memcpy(ctx->u.des3.cbc, iv, 8);
break;
default:
os_free(ctx);
return NULL;
}
return ctx;
}
int crypto_cipher_encrypt(struct crypto_cipher *ctx, const u8 *plain,
u8 *crypt, size_t len)
{
size_t i, j, blocks;
switch (ctx->alg) {
case CRYPTO_CIPHER_ALG_RC4:
if (plain != crypt)
os_memcpy(crypt, plain, len);
rc4_skip(ctx->u.rc4.key, ctx->u.rc4.keylen,
ctx->u.rc4.used_bytes, crypt, len);
ctx->u.rc4.used_bytes += len;
break;
case CRYPTO_CIPHER_ALG_AES:
if (len % ctx->u.aes.block_size)
return -1;
blocks = len / ctx->u.aes.block_size;
for (i = 0; i < blocks; i++) {
for (j = 0; j < ctx->u.aes.block_size; j++)
ctx->u.aes.cbc[j] ^= plain[j];
aes_encrypt(ctx->u.aes.ctx_enc, ctx->u.aes.cbc,
ctx->u.aes.cbc);
os_memcpy(crypt, ctx->u.aes.cbc,
ctx->u.aes.block_size);
plain += ctx->u.aes.block_size;
crypt += ctx->u.aes.block_size;
}
break;
case CRYPTO_CIPHER_ALG_3DES:
if (len % 8)
return -1;
blocks = len / 8;
for (i = 0; i < blocks; i++) {
for (j = 0; j < 8; j++)
ctx->u.des3.cbc[j] ^= plain[j];
des3_encrypt(ctx->u.des3.cbc, &ctx->u.des3.key,
ctx->u.des3.cbc);
os_memcpy(crypt, ctx->u.des3.cbc, 8);
plain += 8;
crypt += 8;
}
break;
default:
return -1;
}
return 0;
}
int crypto_cipher_decrypt(struct crypto_cipher *ctx, const u8 *crypt,
u8 *plain, size_t len)
{
size_t i, j, blocks;
u8 tmp[32];
switch (ctx->alg) {
case CRYPTO_CIPHER_ALG_RC4:
if (plain != crypt)
os_memcpy(plain, crypt, len);
rc4_skip(ctx->u.rc4.key, ctx->u.rc4.keylen,
ctx->u.rc4.used_bytes, plain, len);
ctx->u.rc4.used_bytes += len;
break;
case CRYPTO_CIPHER_ALG_AES:
if (len % ctx->u.aes.block_size)
return -1;
blocks = len / ctx->u.aes.block_size;
for (i = 0; i < blocks; i++) {
os_memcpy(tmp, crypt, ctx->u.aes.block_size);
aes_decrypt(ctx->u.aes.ctx_dec, crypt, plain);
for (j = 0; j < ctx->u.aes.block_size; j++)
plain[j] ^= ctx->u.aes.cbc[j];
os_memcpy(ctx->u.aes.cbc, tmp, ctx->u.aes.block_size);
plain += ctx->u.aes.block_size;
crypt += ctx->u.aes.block_size;
}
break;
case CRYPTO_CIPHER_ALG_3DES:
if (len % 8)
return -1;
blocks = len / 8;
for (i = 0; i < blocks; i++) {
os_memcpy(tmp, crypt, 8);
des3_decrypt(crypt, &ctx->u.des3.key, plain);
for (j = 0; j < 8; j++)
plain[j] ^= ctx->u.des3.cbc[j];
os_memcpy(ctx->u.des3.cbc, tmp, 8);
plain += 8;
crypt += 8;
}
break;
default:
return -1;
}
return 0;
}
void crypto_cipher_deinit(struct crypto_cipher *ctx)
{
switch (ctx->alg) {
case CRYPTO_CIPHER_ALG_AES:
aes_encrypt_deinit(ctx->u.aes.ctx_enc);
aes_decrypt_deinit(ctx->u.aes.ctx_dec);
break;
case CRYPTO_CIPHER_ALG_3DES:
break;
default:
break;
}
os_free(ctx);
}
/* Dummy structures; these are just typecast to struct crypto_rsa_key */
struct crypto_public_key;
struct crypto_private_key;
struct crypto_public_key * crypto_public_key_import(const u8 *key, size_t len)
{
return (struct crypto_public_key *)
crypto_rsa_import_public_key(key, len);
}
struct crypto_private_key * crypto_private_key_import(const u8 *key,
size_t len)
{
return (struct crypto_private_key *)
crypto_rsa_import_private_key(key, len);
}
struct crypto_public_key * crypto_public_key_from_cert(const u8 *buf,
size_t len)
{
/* No X.509 support in crypto_internal.c */
return NULL;
}
static int pkcs1_generate_encryption_block(u8 block_type, size_t modlen,
const u8 *in, size_t inlen,
u8 *out, size_t *outlen)
{
size_t ps_len;
u8 *pos;
/*
* PKCS #1 v1.5, 8.1:
*
* EB = 00 || BT || PS || 00 || D
* BT = 00 or 01 for private-key operation; 02 for public-key operation
* PS = k-3-||D||; at least eight octets
* (BT=0: PS=0x00, BT=1: PS=0xff, BT=2: PS=pseudorandom non-zero)
* k = length of modulus in octets (modlen)
*/
if (modlen < 12 || modlen > *outlen || inlen > modlen - 11) {
wpa_printf(MSG_DEBUG, "PKCS #1: %s - Invalid buffer "
"lengths (modlen=%lu outlen=%lu inlen=%lu)",
__func__, (unsigned long) modlen,
(unsigned long) *outlen,
(unsigned long) inlen);
return -1;
}
pos = out;
*pos++ = 0x00;
*pos++ = block_type; /* BT */
ps_len = modlen - inlen - 3;
switch (block_type) {
case 0:
os_memset(pos, 0x00, ps_len);
pos += ps_len;
break;
case 1:
os_memset(pos, 0xff, ps_len);
pos += ps_len;
break;
case 2:
if (os_get_random(pos, ps_len) < 0) {
wpa_printf(MSG_DEBUG, "PKCS #1: %s - Failed to get "
"random data for PS", __func__);
return -1;
}
while (ps_len--) {
if (*pos == 0x00)
*pos = 0x01;
pos++;
}
break;
default:
wpa_printf(MSG_DEBUG, "PKCS #1: %s - Unsupported block type "
"%d", __func__, block_type);
return -1;
}
*pos++ = 0x00;
os_memcpy(pos, in, inlen); /* D */
return 0;
}
static int crypto_rsa_encrypt_pkcs1(int block_type, struct crypto_rsa_key *key,
int use_private,
const u8 *in, size_t inlen,
u8 *out, size_t *outlen)
{
size_t modlen;
modlen = crypto_rsa_get_modulus_len(key);
if (pkcs1_generate_encryption_block(block_type, modlen, in, inlen,
out, outlen) < 0)
return -1;
return crypto_rsa_exptmod(out, modlen, out, outlen, key, use_private);
}
int crypto_public_key_encrypt_pkcs1_v15(struct crypto_public_key *key,
const u8 *in, size_t inlen,
u8 *out, size_t *outlen)
{
return crypto_rsa_encrypt_pkcs1(2, (struct crypto_rsa_key *) key,
0, in, inlen, out, outlen);
}
int crypto_private_key_sign_pkcs1(struct crypto_private_key *key,
const u8 *in, size_t inlen,
u8 *out, size_t *outlen)
{
return crypto_rsa_encrypt_pkcs1(1, (struct crypto_rsa_key *) key,
1, in, inlen, out, outlen);
}
void crypto_public_key_free(struct crypto_public_key *key)
{
crypto_rsa_free((struct crypto_rsa_key *) key);
}
void crypto_private_key_free(struct crypto_private_key *key)
{
crypto_rsa_free((struct crypto_rsa_key *) key);
}
int crypto_public_key_decrypt_pkcs1(struct crypto_public_key *key,
const u8 *crypt, size_t crypt_len,
u8 *plain, size_t *plain_len)
{
size_t len;
u8 *pos;
len = *plain_len;
if (crypto_rsa_exptmod(crypt, crypt_len, plain, &len,
(struct crypto_rsa_key *) key, 0) < 0)
return -1;
/*
* PKCS #1 v1.5, 8.1:
*
* EB = 00 || BT || PS || 00 || D
* BT = 01
* PS = k-3-||D|| times FF
* k = length of modulus in octets
*/
if (len < 3 + 8 + 16 /* min hash len */ ||
plain[0] != 0x00 || plain[1] != 0x01 || plain[2] != 0xff) {
wpa_printf(MSG_INFO, "LibTomCrypt: Invalid signature EB "
"structure");
return -1;
}
pos = plain + 3;
while (pos < plain + len && *pos == 0xff)
pos++;
if (pos - plain - 2 < 8) {
/* PKCS #1 v1.5, 8.1: At least eight octets long PS */
wpa_printf(MSG_INFO, "LibTomCrypt: Too short signature "
"padding");
return -1;
}
if (pos + 16 /* min hash len */ >= plain + len || *pos != 0x00) {
wpa_printf(MSG_INFO, "LibTomCrypt: Invalid signature EB "
"structure (2)");
return -1;
}
pos++;
len -= pos - plain;
/* Strip PKCS #1 header */
os_memmove(plain, pos, len);
*plain_len = len;
return 0;
}
int crypto_global_init(void)
{
return 0;
}
void crypto_global_deinit(void)
{
}
#ifdef EAP_FAST
int crypto_mod_exp(const u8 *base, size_t base_len,
const u8 *power, size_t power_len,
const u8 *modulus, size_t modulus_len,
u8 *result, size_t *result_len)
{
struct bignum *bn_base, *bn_exp, *bn_modulus, *bn_result;
int ret = 0;
bn_base = bignum_init();
bn_exp = bignum_init();
bn_modulus = bignum_init();
bn_result = bignum_init();
if (bn_base == NULL || bn_exp == NULL || bn_modulus == NULL ||
bn_result == NULL)
goto error;
if (bignum_set_unsigned_bin(bn_base, base, base_len) < 0 ||
bignum_set_unsigned_bin(bn_exp, power, power_len) < 0 ||
bignum_set_unsigned_bin(bn_modulus, modulus, modulus_len) < 0)
goto error;
if (bignum_exptmod(bn_base, bn_exp, bn_modulus, bn_result) < 0)
goto error;
ret = bignum_get_unsigned_bin(bn_result, result, result_len);
error:
bignum_deinit(bn_base);
bignum_deinit(bn_exp);
bignum_deinit(bn_modulus);
bignum_deinit(bn_result);
return ret;
}
#endif /* EAP_FAST */
#endif /* CONFIG_TLS_INTERNAL */
#endif /* EAP_TLS_FUNCS */