1/*
2 * WPA Supplicant / wrapper functions for libcrypto
3 * Copyright (c) 2004-2005, Jouni Malinen <j@w1.fi>
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License version 2 as
7 * published by the Free Software Foundation.
8 *
9 * Alternatively, this software may be distributed under the terms of BSD
10 * license.
11 *
12 * See README and COPYING for more details.
13 */
14
15#include "includes.h"
16#include <openssl/opensslv.h>
17#include <openssl/md4.h>
18#include <openssl/md5.h>
19#include <openssl/sha.h>
20#include <openssl/des.h>
21#include <openssl/aes.h>
22#include <openssl/bn.h>
23#include <openssl/evp.h>
24
25#include "common.h"
26#include "crypto.h"
27
28#if OPENSSL_VERSION_NUMBER < 0x00907000
29#define DES_key_schedule des_key_schedule
30#define DES_cblock des_cblock
31#define DES_set_key(key, schedule) des_set_key((key), *(schedule))
32#define DES_ecb_encrypt(input, output, ks, enc) \
33	des_ecb_encrypt((input), (output), *(ks), (enc))
34#endif /* openssl < 0.9.7 */
35
36
37void md4_vector(size_t num_elem, const u8 *addr[], const size_t *len, u8 *mac)
38{
39	MD4_CTX ctx;
40	size_t i;
41
42	MD4_Init(&ctx);
43	for (i = 0; i < num_elem; i++)
44		MD4_Update(&ctx, addr[i], len[i]);
45	MD4_Final(mac, &ctx);
46}
47
48
49void des_encrypt(const u8 *clear, const u8 *key, u8 *cypher)
50{
51	u8 pkey[8], next, tmp;
52	int i;
53	DES_key_schedule ks;
54
55	/* Add parity bits to the key */
56	next = 0;
57	for (i = 0; i < 7; i++) {
58		tmp = key[i];
59		pkey[i] = (tmp >> i) | next | 1;
60		next = tmp << (7 - i);
61	}
62	pkey[i] = next | 1;
63
64	DES_set_key(&pkey, &ks);
65	DES_ecb_encrypt((DES_cblock *) clear, (DES_cblock *) cypher, &ks,
66			DES_ENCRYPT);
67}
68
69
70void md5_vector(size_t num_elem, const u8 *addr[], const size_t *len, u8 *mac)
71{
72	MD5_CTX ctx;
73	size_t i;
74
75	MD5_Init(&ctx);
76	for (i = 0; i < num_elem; i++)
77		MD5_Update(&ctx, addr[i], len[i]);
78	MD5_Final(mac, &ctx);
79}
80
81
82void sha1_vector(size_t num_elem, const u8 *addr[], const size_t *len, u8 *mac)
83{
84	SHA_CTX ctx;
85	size_t i;
86
87	SHA1_Init(&ctx);
88	for (i = 0; i < num_elem; i++)
89		SHA1_Update(&ctx, addr[i], len[i]);
90	SHA1_Final(mac, &ctx);
91}
92
93
94#ifndef CONFIG_NO_FIPS186_2_PRF
95static void sha1_transform(u8 *state, const u8 data[64])
96{
97	SHA_CTX context;
98	os_memset(&context, 0, sizeof(context));
99	os_memcpy(&context.h0, state, 5 * 4);
100	SHA1_Transform(&context, data);
101	os_memcpy(state, &context.h0, 5 * 4);
102}
103
104
105int fips186_2_prf(const u8 *seed, size_t seed_len, u8 *x, size_t xlen)
106{
107	u8 xkey[64];
108	u32 t[5], _t[5];
109	int i, j, m, k;
110	u8 *xpos = x;
111	u32 carry;
112
113	if (seed_len > sizeof(xkey))
114		seed_len = sizeof(xkey);
115
116	/* FIPS 186-2 + change notice 1 */
117
118	os_memcpy(xkey, seed, seed_len);
119	os_memset(xkey + seed_len, 0, 64 - seed_len);
120	t[0] = 0x67452301;
121	t[1] = 0xEFCDAB89;
122	t[2] = 0x98BADCFE;
123	t[3] = 0x10325476;
124	t[4] = 0xC3D2E1F0;
125
126	m = xlen / 40;
127	for (j = 0; j < m; j++) {
128		/* XSEED_j = 0 */
129		for (i = 0; i < 2; i++) {
130			/* XVAL = (XKEY + XSEED_j) mod 2^b */
131
132			/* w_i = G(t, XVAL) */
133			os_memcpy(_t, t, 20);
134			sha1_transform((u8 *) _t, xkey);
135			_t[0] = host_to_be32(_t[0]);
136			_t[1] = host_to_be32(_t[1]);
137			_t[2] = host_to_be32(_t[2]);
138			_t[3] = host_to_be32(_t[3]);
139			_t[4] = host_to_be32(_t[4]);
140			os_memcpy(xpos, _t, 20);
141
142			/* XKEY = (1 + XKEY + w_i) mod 2^b */
143			carry = 1;
144			for (k = 19; k >= 0; k--) {
145				carry += xkey[k] + xpos[k];
146				xkey[k] = carry & 0xff;
147				carry >>= 8;
148			}
149
150			xpos += 20;
151		}
152		/* x_j = w_0|w_1 */
153	}
154
155	return 0;
156}
157#endif /* CONFIG_NO_FIPS186_2_PRF */
158
159
160void * aes_encrypt_init(const u8 *key, size_t len)
161{
162	AES_KEY *ak;
163	ak = os_malloc(sizeof(*ak));
164	if (ak == NULL)
165		return NULL;
166	if (AES_set_encrypt_key(key, 8 * len, ak) < 0) {
167		os_free(ak);
168		return NULL;
169	}
170	return ak;
171}
172
173
174void aes_encrypt(void *ctx, const u8 *plain, u8 *crypt)
175{
176	AES_encrypt(plain, crypt, ctx);
177}
178
179
180void aes_encrypt_deinit(void *ctx)
181{
182	os_free(ctx);
183}
184
185
186void * aes_decrypt_init(const u8 *key, size_t len)
187{
188	AES_KEY *ak;
189	ak = os_malloc(sizeof(*ak));
190	if (ak == NULL)
191		return NULL;
192	if (AES_set_decrypt_key(key, 8 * len, ak) < 0) {
193		os_free(ak);
194		return NULL;
195	}
196	return ak;
197}
198
199
200void aes_decrypt(void *ctx, const u8 *crypt, u8 *plain)
201{
202	AES_decrypt(crypt, plain, ctx);
203}
204
205
206void aes_decrypt_deinit(void *ctx)
207{
208	os_free(ctx);
209}
210
211
212int crypto_mod_exp(const u8 *base, size_t base_len,
213		   const u8 *power, size_t power_len,
214		   const u8 *modulus, size_t modulus_len,
215		   u8 *result, size_t *result_len)
216{
217	BIGNUM *bn_base, *bn_exp, *bn_modulus, *bn_result;
218	int ret = -1;
219	BN_CTX *ctx;
220
221	ctx = BN_CTX_new();
222	if (ctx == NULL)
223		return -1;
224
225	bn_base = BN_bin2bn(base, base_len, NULL);
226	bn_exp = BN_bin2bn(power, power_len, NULL);
227	bn_modulus = BN_bin2bn(modulus, modulus_len, NULL);
228	bn_result = BN_new();
229
230	if (bn_base == NULL || bn_exp == NULL || bn_modulus == NULL ||
231	    bn_result == NULL)
232		goto error;
233
234	if (BN_mod_exp(bn_result, bn_base, bn_exp, bn_modulus, ctx) != 1)
235		goto error;
236
237	*result_len = BN_bn2bin(bn_result, result);
238	ret = 0;
239
240error:
241	BN_free(bn_base);
242	BN_free(bn_exp);
243	BN_free(bn_modulus);
244	BN_free(bn_result);
245	BN_CTX_free(ctx);
246	return ret;
247}
248
249
250struct crypto_cipher {
251	EVP_CIPHER_CTX enc;
252	EVP_CIPHER_CTX dec;
253};
254
255
256struct crypto_cipher * crypto_cipher_init(enum crypto_cipher_alg alg,
257					  const u8 *iv, const u8 *key,
258					  size_t key_len)
259{
260	struct crypto_cipher *ctx;
261	const EVP_CIPHER *cipher;
262
263	ctx = os_zalloc(sizeof(*ctx));
264	if (ctx == NULL)
265		return NULL;
266
267	switch (alg) {
268#ifndef OPENSSL_NO_RC4
269	case CRYPTO_CIPHER_ALG_RC4:
270		cipher = EVP_rc4();
271		break;
272#endif /* OPENSSL_NO_RC4 */
273#ifndef OPENSSL_NO_AES
274	case CRYPTO_CIPHER_ALG_AES:
275		switch (key_len) {
276		case 16:
277			cipher = EVP_aes_128_cbc();
278			break;
279		case 24:
280			cipher = EVP_aes_192_cbc();
281			break;
282		case 32:
283			cipher = EVP_aes_256_cbc();
284			break;
285		default:
286			os_free(ctx);
287			return NULL;
288		}
289		break;
290#endif /* OPENSSL_NO_AES */
291#ifndef OPENSSL_NO_DES
292	case CRYPTO_CIPHER_ALG_3DES:
293		cipher = EVP_des_ede3_cbc();
294		break;
295	case CRYPTO_CIPHER_ALG_DES:
296		cipher = EVP_des_cbc();
297		break;
298#endif /* OPENSSL_NO_DES */
299#ifndef OPENSSL_NO_RC2
300	case CRYPTO_CIPHER_ALG_RC2:
301		cipher = EVP_rc2_ecb();
302		break;
303#endif /* OPENSSL_NO_RC2 */
304	default:
305		os_free(ctx);
306		return NULL;
307	}
308
309	EVP_CIPHER_CTX_init(&ctx->enc);
310	EVP_CIPHER_CTX_set_padding(&ctx->enc, 0);
311	if (!EVP_EncryptInit_ex(&ctx->enc, cipher, NULL, NULL, NULL) ||
312	    !EVP_CIPHER_CTX_set_key_length(&ctx->enc, key_len) ||
313	    !EVP_EncryptInit_ex(&ctx->enc, cipher, NULL, key, iv)) {
314		EVP_CIPHER_CTX_cleanup(&ctx->enc);
315		os_free(ctx);
316		return NULL;
317	}
318
319	EVP_CIPHER_CTX_init(&ctx->dec);
320	EVP_CIPHER_CTX_set_padding(&ctx->dec, 0);
321	if (!EVP_DecryptInit_ex(&ctx->dec, cipher, NULL, NULL, NULL) ||
322	    !EVP_CIPHER_CTX_set_key_length(&ctx->dec, key_len) ||
323	    !EVP_DecryptInit_ex(&ctx->dec, cipher, NULL, key, iv)) {
324		EVP_CIPHER_CTX_cleanup(&ctx->enc);
325		EVP_CIPHER_CTX_cleanup(&ctx->dec);
326		os_free(ctx);
327		return NULL;
328	}
329
330	return ctx;
331}
332
333
334int crypto_cipher_encrypt(struct crypto_cipher *ctx, const u8 *plain,
335			  u8 *crypt, size_t len)
336{
337	int outl;
338	if (!EVP_EncryptUpdate(&ctx->enc, crypt, &outl, plain, len))
339		return -1;
340	return 0;
341}
342
343
344int crypto_cipher_decrypt(struct crypto_cipher *ctx, const u8 *crypt,
345			  u8 *plain, size_t len)
346{
347	int outl;
348	outl = len;
349	if (!EVP_DecryptUpdate(&ctx->dec, plain, &outl, crypt, len))
350		return -1;
351	return 0;
352}
353
354
355void crypto_cipher_deinit(struct crypto_cipher *ctx)
356{
357	EVP_CIPHER_CTX_cleanup(&ctx->enc);
358	EVP_CIPHER_CTX_cleanup(&ctx->dec);
359	os_free(ctx);
360}
361