1 /* ssl/d1_enc.c */
2 /*
3 * DTLS implementation written by Nagendra Modadugu
4 * (nagendra@cs.stanford.edu) for the OpenSSL project 2005.
5 */
6 /* ====================================================================
7 * Copyright (c) 1998-2005 The OpenSSL Project. All rights reserved.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 *
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 *
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in
18 * the documentation and/or other materials provided with the
19 * distribution.
20 *
21 * 3. All advertising materials mentioning features or use of this
22 * software must display the following acknowledgment:
23 * "This product includes software developed by the OpenSSL Project
24 * for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
25 *
26 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
27 * endorse or promote products derived from this software without
28 * prior written permission. For written permission, please contact
29 * openssl-core@openssl.org.
30 *
31 * 5. Products derived from this software may not be called "OpenSSL"
32 * nor may "OpenSSL" appear in their names without prior written
33 * permission of the OpenSSL Project.
34 *
35 * 6. Redistributions of any form whatsoever must retain the following
36 * acknowledgment:
37 * "This product includes software developed by the OpenSSL Project
38 * for use in the OpenSSL Toolkit (http://www.openssl.org/)"
39 *
40 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
41 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
42 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
43 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
44 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
45 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
46 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
47 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
49 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
50 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
51 * OF THE POSSIBILITY OF SUCH DAMAGE.
52 * ====================================================================
53 *
54 * This product includes cryptographic software written by Eric Young
55 * (eay@cryptsoft.com). This product includes software written by Tim
56 * Hudson (tjh@cryptsoft.com).
57 *
58 */
59 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
60 * All rights reserved.
61 *
62 * This package is an SSL implementation written
63 * by Eric Young (eay@cryptsoft.com).
64 * The implementation was written so as to conform with Netscapes SSL.
65 *
66 * This library is free for commercial and non-commercial use as long as
67 * the following conditions are aheared to. The following conditions
68 * apply to all code found in this distribution, be it the RC4, RSA,
69 * lhash, DES, etc., code; not just the SSL code. The SSL documentation
70 * included with this distribution is covered by the same copyright terms
71 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
72 *
73 * Copyright remains Eric Young's, and as such any Copyright notices in
74 * the code are not to be removed.
75 * If this package is used in a product, Eric Young should be given attribution
76 * as the author of the parts of the library used.
77 * This can be in the form of a textual message at program startup or
78 * in documentation (online or textual) provided with the package.
79 *
80 * Redistribution and use in source and binary forms, with or without
81 * modification, are permitted provided that the following conditions
82 * are met:
83 * 1. Redistributions of source code must retain the copyright
84 * notice, this list of conditions and the following disclaimer.
85 * 2. Redistributions in binary form must reproduce the above copyright
86 * notice, this list of conditions and the following disclaimer in the
87 * documentation and/or other materials provided with the distribution.
88 * 3. All advertising materials mentioning features or use of this software
89 * must display the following acknowledgement:
90 * "This product includes cryptographic software written by
91 * Eric Young (eay@cryptsoft.com)"
92 * The word 'cryptographic' can be left out if the rouines from the library
93 * being used are not cryptographic related :-).
94 * 4. If you include any Windows specific code (or a derivative thereof) from
95 * the apps directory (application code) you must include an acknowledgement:
96 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
97 *
98 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
99 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
100 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
101 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
102 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
103 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
104 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
105 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
106 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
107 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
108 * SUCH DAMAGE.
109 *
110 * The licence and distribution terms for any publically available version or
111 * derivative of this code cannot be changed. i.e. this code cannot simply be
112 * copied and put under another distribution licence
113 * [including the GNU Public Licence.]
114 */
115
116 #include <stdio.h>
117 #include "ssl_locl.h"
118 #ifndef OPENSSL_NO_COMP
119 #include <openssl/comp.h>
120 #endif
121 #include <openssl/evp.h>
122 #include <openssl/hmac.h>
123 #include <openssl/md5.h>
124 #include <openssl/rand.h>
125 #ifdef KSSL_DEBUG
126 #include <openssl/des.h>
127 #endif
128
dtls1_enc(SSL * s,int send)129 int dtls1_enc(SSL *s, int send)
130 {
131 SSL3_RECORD *rec;
132 EVP_CIPHER_CTX *ds;
133 unsigned long l;
134 int bs,i,ii,j,k,n=0;
135 const EVP_CIPHER *enc;
136
137 if (send)
138 {
139 if (EVP_MD_CTX_md(s->write_hash))
140 {
141 n=EVP_MD_CTX_size(s->write_hash);
142 if (n < 0)
143 return -1;
144 }
145 ds=s->enc_write_ctx;
146 rec= &(s->s3->wrec);
147 if (s->enc_write_ctx == NULL)
148 enc=NULL;
149 else
150 {
151 enc=EVP_CIPHER_CTX_cipher(s->enc_write_ctx);
152 if ( rec->data != rec->input)
153 /* we can't write into the input stream */
154 fprintf(stderr, "%s:%d: rec->data != rec->input\n",
155 __FILE__, __LINE__);
156 else if ( EVP_CIPHER_block_size(ds->cipher) > 1)
157 {
158 if (RAND_bytes(rec->input, EVP_CIPHER_block_size(ds->cipher)) <= 0)
159 return -1;
160 }
161 }
162 }
163 else
164 {
165 if (EVP_MD_CTX_md(s->read_hash))
166 {
167 n=EVP_MD_CTX_size(s->read_hash);
168 if (n < 0)
169 return -1;
170 }
171 ds=s->enc_read_ctx;
172 rec= &(s->s3->rrec);
173 if (s->enc_read_ctx == NULL)
174 enc=NULL;
175 else
176 enc=EVP_CIPHER_CTX_cipher(s->enc_read_ctx);
177 }
178
179 #ifdef KSSL_DEBUG
180 printf("dtls1_enc(%d)\n", send);
181 #endif /* KSSL_DEBUG */
182
183 if ((s->session == NULL) || (ds == NULL) ||
184 (enc == NULL))
185 {
186 memmove(rec->data,rec->input,rec->length);
187 rec->input=rec->data;
188 }
189 else
190 {
191 l=rec->length;
192 bs=EVP_CIPHER_block_size(ds->cipher);
193
194 if ((bs != 1) && send)
195 {
196 i=bs-((int)l%bs);
197
198 /* Add weird padding of upto 256 bytes */
199
200 /* we need to add 'i' padding bytes of value j */
201 j=i-1;
202 if (s->options & SSL_OP_TLS_BLOCK_PADDING_BUG)
203 {
204 if (s->s3->flags & TLS1_FLAGS_TLS_PADDING_BUG)
205 j++;
206 }
207 for (k=(int)l; k<(int)(l+i); k++)
208 rec->input[k]=j;
209 l+=i;
210 rec->length+=i;
211 }
212
213 #ifdef KSSL_DEBUG
214 {
215 unsigned long ui;
216 printf("EVP_Cipher(ds=%p,rec->data=%p,rec->input=%p,l=%ld) ==>\n",
217 ds,rec->data,rec->input,l);
218 printf("\tEVP_CIPHER_CTX: %d buf_len, %d key_len [%d %d], %d iv_len\n",
219 ds->buf_len, ds->cipher->key_len,
220 DES_KEY_SZ, DES_SCHEDULE_SZ,
221 ds->cipher->iv_len);
222 printf("\t\tIV: ");
223 for (i=0; i<ds->cipher->iv_len; i++) printf("%02X", ds->iv[i]);
224 printf("\n");
225 printf("\trec->input=");
226 for (ui=0; ui<l; ui++) printf(" %02x", rec->input[ui]);
227 printf("\n");
228 }
229 #endif /* KSSL_DEBUG */
230
231 if (!send)
232 {
233 if (l == 0 || l%bs != 0)
234 {
235 SSLerr(SSL_F_DTLS1_ENC,SSL_R_BLOCK_CIPHER_PAD_IS_WRONG);
236 ssl3_send_alert(s,SSL3_AL_FATAL,SSL_AD_DECRYPTION_FAILED);
237 return 0;
238 }
239 }
240
241 EVP_Cipher(ds,rec->data,rec->input,l);
242
243 #ifdef KSSL_DEBUG
244 {
245 unsigned long i;
246 printf("\trec->data=");
247 for (i=0; i<l; i++)
248 printf(" %02x", rec->data[i]); printf("\n");
249 }
250 #endif /* KSSL_DEBUG */
251
252 if ((bs != 1) && !send)
253 {
254 ii=i=rec->data[l-1]; /* padding_length */
255 i++;
256 if (s->options&SSL_OP_TLS_BLOCK_PADDING_BUG)
257 {
258 /* First packet is even in size, so check */
259 if ((memcmp(s->s3->read_sequence,
260 "\0\0\0\0\0\0\0\0",8) == 0) && !(ii & 1))
261 s->s3->flags|=TLS1_FLAGS_TLS_PADDING_BUG;
262 if (s->s3->flags & TLS1_FLAGS_TLS_PADDING_BUG)
263 i--;
264 }
265 /* TLS 1.0 does not bound the number of padding bytes by the block size.
266 * All of them must have value 'padding_length'. */
267 if (i > (int)rec->length)
268 {
269 /* Incorrect padding. SSLerr() and ssl3_alert are done
270 * by caller: we don't want to reveal whether this is
271 * a decryption error or a MAC verification failure
272 * (see http://www.openssl.org/~bodo/tls-cbc.txt)
273 */
274 return -1;
275 }
276 for (j=(int)(l-i); j<(int)l; j++)
277 {
278 if (rec->data[j] != ii)
279 {
280 /* Incorrect padding */
281 return -1;
282 }
283 }
284 rec->length-=i;
285
286 rec->data += bs; /* skip the implicit IV */
287 rec->input += bs;
288 rec->length -= bs;
289 }
290 }
291 return(1);
292 }
293
294