xref: /minix/crypto/external/bsd/openssl/dist/ssl/s2_enc.c (revision ebfedea0)
1 /* ssl/s2_enc.c */
2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
3  * All rights reserved.
4  *
5  * This package is an SSL implementation written
6  * by Eric Young (eay@cryptsoft.com).
7  * The implementation was written so as to conform with Netscapes SSL.
8  *
9  * This library is free for commercial and non-commercial use as long as
10  * the following conditions are aheared to.  The following conditions
11  * apply to all code found in this distribution, be it the RC4, RSA,
12  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
13  * included with this distribution is covered by the same copyright terms
14  * except that the holder is Tim Hudson (tjh@cryptsoft.com).
15  *
16  * Copyright remains Eric Young's, and as such any Copyright notices in
17  * the code are not to be removed.
18  * If this package is used in a product, Eric Young should be given attribution
19  * as the author of the parts of the library used.
20  * This can be in the form of a textual message at program startup or
21  * in documentation (online or textual) provided with the package.
22  *
23  * Redistribution and use in source and binary forms, with or without
24  * modification, are permitted provided that the following conditions
25  * are met:
26  * 1. Redistributions of source code must retain the copyright
27  *    notice, this list of conditions and the following disclaimer.
28  * 2. Redistributions in binary form must reproduce the above copyright
29  *    notice, this list of conditions and the following disclaimer in the
30  *    documentation and/or other materials provided with the distribution.
31  * 3. All advertising materials mentioning features or use of this software
32  *    must display the following acknowledgement:
33  *    "This product includes cryptographic software written by
34  *     Eric Young (eay@cryptsoft.com)"
35  *    The word 'cryptographic' can be left out if the rouines from the library
36  *    being used are not cryptographic related :-).
37  * 4. If you include any Windows specific code (or a derivative thereof) from
38  *    the apps directory (application code) you must include an acknowledgement:
39  *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
40  *
41  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
42  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
44  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
45  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
46  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
47  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
49  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
50  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
51  * SUCH DAMAGE.
52  *
53  * The licence and distribution terms for any publically available version or
54  * derivative of this code cannot be changed.  i.e. this code cannot simply be
55  * copied and put under another distribution licence
56  * [including the GNU Public Licence.]
57  */
58 
59 #include "ssl_locl.h"
60 #ifndef OPENSSL_NO_SSL2
61 #include <stdio.h>
62 
63 int ssl2_enc_init(SSL *s, int client)
64 	{
65 	/* Max number of bytes needed */
66 	EVP_CIPHER_CTX *rs,*ws;
67 	const EVP_CIPHER *c;
68 	const EVP_MD *md;
69 	int num;
70 
71 	if (!ssl_cipher_get_evp(s->session,&c,&md,NULL,NULL,NULL))
72 		{
73 		ssl2_return_error(s,SSL2_PE_NO_CIPHER);
74 		SSLerr(SSL_F_SSL2_ENC_INIT,SSL_R_PROBLEMS_MAPPING_CIPHER_FUNCTIONS);
75 		return(0);
76 		}
77 	ssl_replace_hash(&s->read_hash,md);
78 	ssl_replace_hash(&s->write_hash,md);
79 
80 	if ((s->enc_read_ctx == NULL) &&
81 		((s->enc_read_ctx=(EVP_CIPHER_CTX *)
82 		OPENSSL_malloc(sizeof(EVP_CIPHER_CTX))) == NULL))
83 		goto err;
84 
85 	/* make sure it's intialized in case the malloc for enc_write_ctx fails
86 	 * and we exit with an error */
87 	rs= s->enc_read_ctx;
88 	EVP_CIPHER_CTX_init(rs);
89 
90 	if ((s->enc_write_ctx == NULL) &&
91 		((s->enc_write_ctx=(EVP_CIPHER_CTX *)
92 		OPENSSL_malloc(sizeof(EVP_CIPHER_CTX))) == NULL))
93 		goto err;
94 
95 	ws= s->enc_write_ctx;
96 	EVP_CIPHER_CTX_init(ws);
97 
98 	num=c->key_len;
99 	s->s2->key_material_length=num*2;
100 	OPENSSL_assert(s->s2->key_material_length <= sizeof s->s2->key_material);
101 
102 	if (ssl2_generate_key_material(s) <= 0)
103 		return 0;
104 
105 	OPENSSL_assert(c->iv_len <= (int)sizeof(s->session->key_arg));
106 	EVP_EncryptInit_ex(ws,c,NULL,&(s->s2->key_material[(client)?num:0]),
107 		s->session->key_arg);
108 	EVP_DecryptInit_ex(rs,c,NULL,&(s->s2->key_material[(client)?0:num]),
109 		s->session->key_arg);
110 	s->s2->read_key=  &(s->s2->key_material[(client)?0:num]);
111 	s->s2->write_key= &(s->s2->key_material[(client)?num:0]);
112 	return(1);
113 err:
114 	SSLerr(SSL_F_SSL2_ENC_INIT,ERR_R_MALLOC_FAILURE);
115 	return(0);
116 	}
117 
118 /* read/writes from s->s2->mac_data using length for encrypt and
119  * decrypt.  It sets s->s2->padding and s->[rw]length
120  * if we are encrypting */
121 void ssl2_enc(SSL *s, int send)
122 	{
123 	EVP_CIPHER_CTX *ds;
124 	unsigned long l;
125 	int bs;
126 
127 	if (send)
128 		{
129 		ds=s->enc_write_ctx;
130 		l=s->s2->wlength;
131 		}
132 	else
133 		{
134 		ds=s->enc_read_ctx;
135 		l=s->s2->rlength;
136 		}
137 
138 	/* check for NULL cipher */
139 	if (ds == NULL) return;
140 
141 
142 	bs=ds->cipher->block_size;
143 	/* This should be using (bs-1) and bs instead of 7 and 8, but
144 	 * what the hell. */
145 	if (bs == 8)
146 		l=(l+7)/8*8;
147 
148 	EVP_Cipher(ds,s->s2->mac_data,s->s2->mac_data,l);
149 	}
150 
151 void ssl2_mac(SSL *s, unsigned char *md, int send)
152 	{
153 	EVP_MD_CTX c;
154 	unsigned char sequence[4],*p,*sec,*act;
155 	unsigned long seq;
156 	unsigned int len;
157 
158 	if (send)
159 		{
160 		seq=s->s2->write_sequence;
161 		sec=s->s2->write_key;
162 		len=s->s2->wact_data_length;
163 		act=s->s2->wact_data;
164 		}
165 	else
166 		{
167 		seq=s->s2->read_sequence;
168 		sec=s->s2->read_key;
169 		len=s->s2->ract_data_length;
170 		act=s->s2->ract_data;
171 		}
172 
173 	p= &(sequence[0]);
174 	l2n(seq,p);
175 
176 	/* There has to be a MAC algorithm. */
177 	EVP_MD_CTX_init(&c);
178 	EVP_MD_CTX_copy(&c, s->read_hash);
179 	EVP_DigestUpdate(&c,sec,
180 		EVP_CIPHER_CTX_key_length(s->enc_read_ctx));
181 	EVP_DigestUpdate(&c,act,len);
182 	/* the above line also does the pad data */
183 	EVP_DigestUpdate(&c,sequence,4);
184 	EVP_DigestFinal_ex(&c,md,NULL);
185 	EVP_MD_CTX_cleanup(&c);
186 	}
187 #else /* !OPENSSL_NO_SSL2 */
188 
189 # if PEDANTIC
190 static void *dummy=&dummy;
191 # endif
192 
193 #endif
194