e_rc4_hmac_md5.c revision 284295 
1/* ====================================================================
2 * Copyright (c) 2011 The OpenSSL Project.  All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 *
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 *
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in
13 *    the documentation and/or other materials provided with the
14 *    distribution.
15 *
16 * 3. All advertising materials mentioning features or use of this
17 *    software must display the following acknowledgment:
18 *    "This product includes software developed by the OpenSSL Project
19 *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
20 *
21 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
22 *    endorse or promote products derived from this software without
23 *    prior written permission. For written permission, please contact
24 *    licensing@OpenSSL.org.
25 *
26 * 5. Products derived from this software may not be called "OpenSSL"
27 *    nor may "OpenSSL" appear in their names without prior written
28 *    permission of the OpenSSL Project.
29 *
30 * 6. Redistributions of any form whatsoever must retain the following
31 *    acknowledgment:
32 *    "This product includes software developed by the OpenSSL Project
33 *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
34 *
35 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
36 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
37 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
38 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
39 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
40 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
41 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
42 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
43 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
44 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
45 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
46 * OF THE POSSIBILITY OF SUCH DAMAGE.
47 * ====================================================================
48 */
49
50#include <openssl/opensslconf.h>
51
52#include <stdio.h>
53#include <string.h>
54
55#if !defined(OPENSSL_NO_RC4) && !defined(OPENSSL_NO_MD5)
56
57#include <openssl/crypto.h>
58#include <openssl/evp.h>
59#include <openssl/objects.h>
60#include <openssl/rc4.h>
61#include <openssl/md5.h>
62
63#ifndef EVP_CIPH_FLAG_AEAD_CIPHER
64#define EVP_CIPH_FLAG_AEAD_CIPHER	0x200000
65#define EVP_CTRL_AEAD_TLS1_AAD		0x16
66#define EVP_CTRL_AEAD_SET_MAC_KEY	0x17
67#endif
68
69/* FIXME: surely this is available elsewhere? */
70#define EVP_RC4_KEY_SIZE		16
71
72typedef struct
73    {
74    RC4_KEY		ks;
75    MD5_CTX		head,tail,md;
76    size_t		payload_length;
77    } EVP_RC4_HMAC_MD5;
78
79#define NO_PAYLOAD_LENGTH	((size_t)-1)
80
81void rc4_md5_enc (RC4_KEY *key, const void *in0, void *out,
82		MD5_CTX *ctx,const void *inp,size_t blocks);
83
84#define data(ctx) ((EVP_RC4_HMAC_MD5 *)(ctx)->cipher_data)
85
86static int rc4_hmac_md5_init_key(EVP_CIPHER_CTX *ctx,
87			const unsigned char *inkey,
88			const unsigned char *iv, int enc)
89	{
90	EVP_RC4_HMAC_MD5 *key = data(ctx);
91
92	RC4_set_key(&key->ks,EVP_CIPHER_CTX_key_length(ctx),
93		    inkey);
94
95	MD5_Init(&key->head);	/* handy when benchmarking */
96	key->tail = key->head;
97	key->md   = key->head;
98
99	key->payload_length = NO_PAYLOAD_LENGTH;
100
101	return 1;
102	}
103
104#if	!defined(OPENSSL_NO_ASM) &&	( \
105	defined(__x86_64)	|| defined(__x86_64__)	|| \
106	defined(_M_AMD64)	|| defined(_M_X64)	|| \
107	defined(__INTEL__)		) && \
108	!(defined(__APPLE__) && defined(__MACH__))
109#define	STITCHED_CALL
110#endif
111
112#if !defined(STITCHED_CALL)
113#define	rc4_off 0
114#define	md5_off 0
115#endif
116
117static int rc4_hmac_md5_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out,
118		      const unsigned char *in, size_t len)
119	{
120	EVP_RC4_HMAC_MD5 *key = data(ctx);
121#if defined(STITCHED_CALL)
122	size_t	rc4_off = 32-1-(key->ks.x&(32-1)),	/* 32 is $MOD from rc4_md5-x86_64.pl */
123		md5_off = MD5_CBLOCK-key->md.num,
124		blocks;
125	unsigned int l;
126	extern unsigned int OPENSSL_ia32cap_P[];
127#endif
128	size_t	plen = key->payload_length;
129
130	if (plen!=NO_PAYLOAD_LENGTH && len!=(plen+MD5_DIGEST_LENGTH)) return 0;
131
132	if (ctx->encrypt) {
133		if (plen==NO_PAYLOAD_LENGTH) plen = len;
134#if defined(STITCHED_CALL)
135		/* cipher has to "fall behind" */
136		if (rc4_off>md5_off) md5_off+=MD5_CBLOCK;
137
138		if (plen>md5_off && (blocks=(plen-md5_off)/MD5_CBLOCK) &&
139		    (OPENSSL_ia32cap_P[0]&(1<<20))==0) {
140			MD5_Update(&key->md,in,md5_off);
141			RC4(&key->ks,rc4_off,in,out);
142
143			rc4_md5_enc(&key->ks,in+rc4_off,out+rc4_off,
144				&key->md,in+md5_off,blocks);
145			blocks *= MD5_CBLOCK;
146			rc4_off += blocks;
147			md5_off += blocks;
148			key->md.Nh += blocks>>29;
149			key->md.Nl += blocks<<=3;
150			if (key->md.Nl<(unsigned int)blocks) key->md.Nh++;
151		} else {
152			rc4_off = 0;
153			md5_off = 0;
154		}
155#endif
156		MD5_Update(&key->md,in+md5_off,plen-md5_off);
157
158		if (plen!=len) {	/* "TLS" mode of operation */
159			if (in!=out)
160				memcpy(out+rc4_off,in+rc4_off,plen-rc4_off);
161
162			/* calculate HMAC and append it to payload */
163			MD5_Final(out+plen,&key->md);
164			key->md = key->tail;
165			MD5_Update(&key->md,out+plen,MD5_DIGEST_LENGTH);
166			MD5_Final(out+plen,&key->md);
167			/* encrypt HMAC at once */
168			RC4(&key->ks,len-rc4_off,out+rc4_off,out+rc4_off);
169		} else {
170			RC4(&key->ks,len-rc4_off,in+rc4_off,out+rc4_off);
171		}
172	} else {
173		unsigned char mac[MD5_DIGEST_LENGTH];
174#if defined(STITCHED_CALL)
175		/* digest has to "fall behind" */
176		if (md5_off>rc4_off)	rc4_off += 2*MD5_CBLOCK;
177		else			rc4_off += MD5_CBLOCK;
178
179		if (len>rc4_off && (blocks=(len-rc4_off)/MD5_CBLOCK) &&
180		    (OPENSSL_ia32cap_P[0]&(1<<20))==0) {
181			RC4(&key->ks,rc4_off,in,out);
182			MD5_Update(&key->md,out,md5_off);
183
184			rc4_md5_enc(&key->ks,in+rc4_off,out+rc4_off,
185				&key->md,out+md5_off,blocks);
186			blocks *= MD5_CBLOCK;
187			rc4_off += blocks;
188			md5_off += blocks;
189			l = (key->md.Nl+(blocks<<3))&0xffffffffU;
190			if (l<key->md.Nl) key->md.Nh++;
191			key->md.Nl  = l;
192			key->md.Nh += blocks>>29;
193		} else {
194			md5_off=0;
195			rc4_off=0;
196		}
197#endif
198		/* decrypt HMAC at once */
199		RC4(&key->ks,len-rc4_off,in+rc4_off,out+rc4_off);
200		if (plen!=NO_PAYLOAD_LENGTH) {	/* "TLS" mode of operation */
201			MD5_Update(&key->md,out+md5_off,plen-md5_off);
202
203			/* calculate HMAC and verify it */
204			MD5_Final(mac,&key->md);
205			key->md = key->tail;
206			MD5_Update(&key->md,mac,MD5_DIGEST_LENGTH);
207			MD5_Final(mac,&key->md);
208
209			if (CRYPTO_memcmp(out + plen, mac, MD5_DIGEST_LENGTH))
210				return 0;
211		} else {
212			MD5_Update(&key->md,out+md5_off,len-md5_off);
213		}
214	}
215
216	key->payload_length = NO_PAYLOAD_LENGTH;
217
218	return 1;
219	}
220
221static int rc4_hmac_md5_ctrl(EVP_CIPHER_CTX *ctx, int type, int arg, void *ptr)
222	{
223	EVP_RC4_HMAC_MD5 *key = data(ctx);
224
225	switch (type)
226		{
227	case EVP_CTRL_AEAD_SET_MAC_KEY:
228		{
229		unsigned int  i;
230		unsigned char hmac_key[64];
231
232		memset (hmac_key,0,sizeof(hmac_key));
233
234		if (arg > (int)sizeof(hmac_key)) {
235			MD5_Init(&key->head);
236			MD5_Update(&key->head,ptr,arg);
237			MD5_Final(hmac_key,&key->head);
238		} else {
239			memcpy(hmac_key,ptr,arg);
240		}
241
242		for (i=0;i<sizeof(hmac_key);i++)
243			hmac_key[i] ^= 0x36;		/* ipad */
244		MD5_Init(&key->head);
245		MD5_Update(&key->head,hmac_key,sizeof(hmac_key));
246
247		for (i=0;i<sizeof(hmac_key);i++)
248			hmac_key[i] ^= 0x36^0x5c;	/* opad */
249		MD5_Init(&key->tail);
250		MD5_Update(&key->tail,hmac_key,sizeof(hmac_key));
251
252		return 1;
253		}
254	case EVP_CTRL_AEAD_TLS1_AAD:
255		{
256		unsigned char *p=ptr;
257		unsigned int   len=p[arg-2]<<8|p[arg-1];
258
259		if (!ctx->encrypt)
260			{
261			len -= MD5_DIGEST_LENGTH;
262			p[arg-2] = len>>8;
263			p[arg-1] = len;
264			}
265		key->payload_length=len;
266		key->md = key->head;
267		MD5_Update(&key->md,p,arg);
268
269		return MD5_DIGEST_LENGTH;
270		}
271	default:
272		return -1;
273		}
274	}
275
276static EVP_CIPHER r4_hmac_md5_cipher=
277	{
278#ifdef NID_rc4_hmac_md5
279	NID_rc4_hmac_md5,
280#else
281	NID_undef,
282#endif
283	1,EVP_RC4_KEY_SIZE,0,
284	EVP_CIPH_STREAM_CIPHER|EVP_CIPH_VARIABLE_LENGTH|EVP_CIPH_FLAG_AEAD_CIPHER,
285	rc4_hmac_md5_init_key,
286	rc4_hmac_md5_cipher,
287	NULL,
288	sizeof(EVP_RC4_HMAC_MD5),
289	NULL,
290	NULL,
291	rc4_hmac_md5_ctrl,
292	NULL
293	};
294
295const EVP_CIPHER *EVP_rc4_hmac_md5(void)
296	{
297	return(&r4_hmac_md5_cipher);
298	}
299#endif
300