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 (s->write_hash != NULL)
140 n=EVP_MD_size(s->write_hash);
141 ds=s->enc_write_ctx;
142 rec= &(s->s3->wrec);
143 if (s->enc_write_ctx == NULL)
144 enc=NULL;
145 else
146 {
147 enc=EVP_CIPHER_CTX_cipher(s->enc_write_ctx);
148 if ( rec->data != rec->input)
149 /* we can't write into the input stream */
150 fprintf(stderr, "%s:%d: rec->data != rec->input\n",
151 __FILE__, __LINE__);
152 else if ( EVP_CIPHER_block_size(ds->cipher) > 1)
153 {
154 if (!RAND_bytes(rec->input, EVP_CIPHER_block_size(ds->cipher)))
155 return -1;
156 }
157 }
158 }
159 else
160 {
161 if (s->read_hash != NULL)
162 n=EVP_MD_size(s->read_hash);
163 ds=s->enc_read_ctx;
164 rec= &(s->s3->rrec);
165 if (s->enc_read_ctx == NULL)
166 enc=NULL;
167 else
168 enc=EVP_CIPHER_CTX_cipher(s->enc_read_ctx);
169 }
170
171 #ifdef KSSL_DEBUG
172 printf("dtls1_enc(%d)\n", send);
173 #endif /* KSSL_DEBUG */
174
175 if ((s->session == NULL) || (ds == NULL) ||
176 (enc == NULL))
177 {
178 memmove(rec->data,rec->input,rec->length);
179 rec->input=rec->data;
180 }
181 else
182 {
183 l=rec->length;
184 bs=EVP_CIPHER_block_size(ds->cipher);
185
186 if ((bs != 1) && send)
187 {
188 i=bs-((int)l%bs);
189
190 /* Add weird padding of upto 256 bytes */
191
192 /* we need to add 'i' padding bytes of value j */
193 j=i-1;
194 if (s->options & SSL_OP_TLS_BLOCK_PADDING_BUG)
195 {
196 if (s->s3->flags & TLS1_FLAGS_TLS_PADDING_BUG)
197 j++;
198 }
199 for (k=(int)l; k<(int)(l+i); k++)
200 rec->input[k]=j;
201 l+=i;
202 rec->length+=i;
203 }
204
205 #ifdef KSSL_DEBUG
206 {
207 unsigned long ui;
208 printf("EVP_Cipher(ds=%p,rec->data=%p,rec->input=%p,l=%ld) ==>\n",
209 (void *)ds,rec->data,rec->input,l);
210 printf("\tEVP_CIPHER_CTX: %d buf_len, %d key_len [%ld %ld], %d iv_len\n",
211 ds->buf_len, ds->cipher->key_len,
212 (unsigned long)DES_KEY_SZ,
213 (unsigned long)DES_SCHEDULE_SZ,
214 ds->cipher->iv_len);
215 printf("\t\tIV: ");
216 for (i=0; i<ds->cipher->iv_len; i++) printf("%02X", ds->iv[i]);
217 printf("\n");
218 printf("\trec->input=");
219 for (ui=0; ui<l; ui++) printf(" %02x", rec->input[ui]);
220 printf("\n");
221 }
222 #endif /* KSSL_DEBUG */
223
224 if (!send)
225 {
226 if (l == 0 || l%bs != 0)
227 {
228 SSLerr(SSL_F_DTLS1_ENC,SSL_R_BLOCK_CIPHER_PAD_IS_WRONG);
229 ssl3_send_alert(s,SSL3_AL_FATAL,SSL_AD_DECRYPTION_FAILED);
230 return 0;
231 }
232 }
233
234 EVP_Cipher(ds,rec->data,rec->input,l);
235
236 #ifdef KSSL_DEBUG
237 {
238 unsigned long ki;
239 printf("\trec->data=");
240 for (ki=0; ki<l; ki++)
241 printf(" %02x", rec->data[ki]); printf("\n");
242 }
243 #endif /* KSSL_DEBUG */
244
245 if ((bs != 1) && !send)
246 {
247 ii=i=rec->data[l-1]; /* padding_length */
248 i++;
249 if (s->options&SSL_OP_TLS_BLOCK_PADDING_BUG)
250 {
251 /* First packet is even in size, so check */
252 if ((memcmp(s->s3->read_sequence,
253 "\0\0\0\0\0\0\0\0",8) == 0) && !(ii & 1))
254 s->s3->flags|=TLS1_FLAGS_TLS_PADDING_BUG;
255 if (s->s3->flags & TLS1_FLAGS_TLS_PADDING_BUG)
256 i--;
257 }
258 /* TLS 1.0 does not bound the number of padding bytes by the block size.
259 * All of them must have value 'padding_length'. */
260 if (i > (int)rec->length)
261 {
262 /* Incorrect padding. SSLerr() and ssl3_alert are done
263 * by caller: we don't want to reveal whether this is
264 * a decryption error or a MAC verification failure
265 * (see http://www.openssl.org/~bodo/tls-cbc.txt)
266 */
267 return -1;
268 }
269 for (j=(int)(l-i); j<(int)l; j++)
270 {
271 if (rec->data[j] != ii)
272 {
273 /* Incorrect padding */
274 return -1;
275 }
276 }
277 rec->length-=i;
278
279 rec->data += bs; /* skip the implicit IV */
280 rec->input += bs;
281 rec->length -= bs;
282 }
283 }
284 return(1);
285 }
286
287