1 /*
2 * Copyright 2011-2021 The OpenSSL Project Authors. All Rights Reserved.
3 *
4 * Licensed under the Apache License 2.0 (the "License"). You may not use
5 * this file except in compliance with the License. You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
8 */
9
10 /*
11 * MD5 and RC4 low level APIs are deprecated for public use, but still ok for
12 * internal use.
13 */
14 #include "internal/deprecated.h"
15
16 #include "internal/cryptlib.h"
17 #include <openssl/opensslconf.h>
18
19 #include <stdio.h>
20 #include <string.h>
21
22 #if !defined(OPENSSL_NO_RC4) && !defined(OPENSSL_NO_MD5)
23
24 # include <openssl/crypto.h>
25 # include <openssl/evp.h>
26 # include <openssl/objects.h>
27 # include <openssl/rc4.h>
28 # include <openssl/md5.h>
29 # include "crypto/evp.h"
30
31 typedef struct {
32 RC4_KEY ks;
33 MD5_CTX head, tail, md;
34 size_t payload_length;
35 } EVP_RC4_HMAC_MD5;
36
37 # define NO_PAYLOAD_LENGTH ((size_t)-1)
38
39 void rc4_md5_enc(RC4_KEY *key, const void *in0, void *out,
40 MD5_CTX *ctx, const void *inp, size_t blocks);
41
42 # define data(ctx) ((EVP_RC4_HMAC_MD5 *)EVP_CIPHER_CTX_get_cipher_data(ctx))
43
rc4_hmac_md5_init_key(EVP_CIPHER_CTX * ctx,const unsigned char * inkey,const unsigned char * iv,int enc)44 static int rc4_hmac_md5_init_key(EVP_CIPHER_CTX *ctx,
45 const unsigned char *inkey,
46 const unsigned char *iv, int enc)
47 {
48 EVP_RC4_HMAC_MD5 *key = data(ctx);
49 const int keylen = EVP_CIPHER_CTX_get_key_length(ctx);
50
51 if (keylen <= 0)
52 return 0;
53
54 RC4_set_key(&key->ks, keylen, inkey);
55
56 MD5_Init(&key->head); /* handy when benchmarking */
57 key->tail = key->head;
58 key->md = key->head;
59
60 key->payload_length = NO_PAYLOAD_LENGTH;
61
62 return 1;
63 }
64
65 # if defined(RC4_ASM) && defined(MD5_ASM) && ( \
66 defined(__x86_64) || defined(__x86_64__) || \
67 defined(_M_AMD64) || defined(_M_X64) )
68 # define STITCHED_CALL
69 # endif
70
71 # if !defined(STITCHED_CALL)
72 # define rc4_off 0
73 # define md5_off 0
74 # endif
75
rc4_hmac_md5_cipher(EVP_CIPHER_CTX * ctx,unsigned char * out,const unsigned char * in,size_t len)76 static int rc4_hmac_md5_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out,
77 const unsigned char *in, size_t len)
78 {
79 EVP_RC4_HMAC_MD5 *key = data(ctx);
80 # if defined(STITCHED_CALL)
81 size_t rc4_off = 32 - 1 - (key->ks.x & (32 - 1)), /* 32 is $MOD from
82 * rc4_md5-x86_64.pl */
83 md5_off = MD5_CBLOCK - key->md.num, blocks;
84 unsigned int l;
85 # endif
86 size_t plen = key->payload_length;
87
88 if (plen != NO_PAYLOAD_LENGTH && len != (plen + MD5_DIGEST_LENGTH))
89 return 0;
90
91 if (EVP_CIPHER_CTX_is_encrypting(ctx)) {
92 if (plen == NO_PAYLOAD_LENGTH)
93 plen = len;
94 # if defined(STITCHED_CALL)
95 /* cipher has to "fall behind" */
96 if (rc4_off > md5_off)
97 md5_off += MD5_CBLOCK;
98
99 if (plen > md5_off && (blocks = (plen - md5_off) / MD5_CBLOCK) &&
100 (OPENSSL_ia32cap_P[0] & (1 << 20)) == 0) {
101 MD5_Update(&key->md, in, md5_off);
102 RC4(&key->ks, rc4_off, in, out);
103
104 rc4_md5_enc(&key->ks, in + rc4_off, out + rc4_off,
105 &key->md, in + md5_off, blocks);
106 blocks *= MD5_CBLOCK;
107 rc4_off += blocks;
108 md5_off += blocks;
109 key->md.Nh += blocks >> 29;
110 key->md.Nl += blocks <<= 3;
111 if (key->md.Nl < (unsigned int)blocks)
112 key->md.Nh++;
113 } else {
114 rc4_off = 0;
115 md5_off = 0;
116 }
117 # endif
118 MD5_Update(&key->md, in + md5_off, plen - md5_off);
119
120 if (plen != len) { /* "TLS" mode of operation */
121 if (in != out)
122 memcpy(out + rc4_off, in + rc4_off, plen - rc4_off);
123
124 /* calculate HMAC and append it to payload */
125 MD5_Final(out + plen, &key->md);
126 key->md = key->tail;
127 MD5_Update(&key->md, out + plen, MD5_DIGEST_LENGTH);
128 MD5_Final(out + plen, &key->md);
129 /* encrypt HMAC at once */
130 RC4(&key->ks, len - rc4_off, out + rc4_off, out + rc4_off);
131 } else {
132 RC4(&key->ks, len - rc4_off, in + rc4_off, out + rc4_off);
133 }
134 } else {
135 unsigned char mac[MD5_DIGEST_LENGTH];
136 # if defined(STITCHED_CALL)
137 /* digest has to "fall behind" */
138 if (md5_off > rc4_off)
139 rc4_off += 2 * MD5_CBLOCK;
140 else
141 rc4_off += MD5_CBLOCK;
142
143 if (len > rc4_off && (blocks = (len - rc4_off) / MD5_CBLOCK) &&
144 (OPENSSL_ia32cap_P[0] & (1 << 20)) == 0) {
145 RC4(&key->ks, rc4_off, in, out);
146 MD5_Update(&key->md, out, md5_off);
147
148 rc4_md5_enc(&key->ks, in + rc4_off, out + rc4_off,
149 &key->md, out + md5_off, blocks);
150 blocks *= MD5_CBLOCK;
151 rc4_off += blocks;
152 md5_off += blocks;
153 l = (key->md.Nl + (blocks << 3)) & 0xffffffffU;
154 if (l < key->md.Nl)
155 key->md.Nh++;
156 key->md.Nl = l;
157 key->md.Nh += blocks >> 29;
158 } else {
159 md5_off = 0;
160 rc4_off = 0;
161 }
162 # endif
163 /* decrypt HMAC at once */
164 RC4(&key->ks, len - rc4_off, in + rc4_off, out + rc4_off);
165 if (plen != NO_PAYLOAD_LENGTH) { /* "TLS" mode of operation */
166 MD5_Update(&key->md, out + md5_off, plen - md5_off);
167
168 /* calculate HMAC and verify it */
169 MD5_Final(mac, &key->md);
170 key->md = key->tail;
171 MD5_Update(&key->md, mac, MD5_DIGEST_LENGTH);
172 MD5_Final(mac, &key->md);
173
174 if (CRYPTO_memcmp(out + plen, mac, MD5_DIGEST_LENGTH))
175 return 0;
176 } else {
177 MD5_Update(&key->md, out + md5_off, len - md5_off);
178 }
179 }
180
181 key->payload_length = NO_PAYLOAD_LENGTH;
182
183 return 1;
184 }
185
rc4_hmac_md5_ctrl(EVP_CIPHER_CTX * ctx,int type,int arg,void * ptr)186 static int rc4_hmac_md5_ctrl(EVP_CIPHER_CTX *ctx, int type, int arg,
187 void *ptr)
188 {
189 EVP_RC4_HMAC_MD5 *key = data(ctx);
190
191 switch (type) {
192 case EVP_CTRL_AEAD_SET_MAC_KEY:
193 {
194 unsigned int i;
195 unsigned char hmac_key[64];
196
197 memset(hmac_key, 0, sizeof(hmac_key));
198
199 if (arg > (int)sizeof(hmac_key)) {
200 MD5_Init(&key->head);
201 MD5_Update(&key->head, ptr, arg);
202 MD5_Final(hmac_key, &key->head);
203 } else {
204 memcpy(hmac_key, ptr, arg);
205 }
206
207 for (i = 0; i < sizeof(hmac_key); i++)
208 hmac_key[i] ^= 0x36; /* ipad */
209 MD5_Init(&key->head);
210 MD5_Update(&key->head, hmac_key, sizeof(hmac_key));
211
212 for (i = 0; i < sizeof(hmac_key); i++)
213 hmac_key[i] ^= 0x36 ^ 0x5c; /* opad */
214 MD5_Init(&key->tail);
215 MD5_Update(&key->tail, hmac_key, sizeof(hmac_key));
216
217 OPENSSL_cleanse(hmac_key, sizeof(hmac_key));
218
219 return 1;
220 }
221 case EVP_CTRL_AEAD_TLS1_AAD:
222 {
223 unsigned char *p = ptr;
224 unsigned int len;
225
226 if (arg != EVP_AEAD_TLS1_AAD_LEN)
227 return -1;
228
229 len = p[arg - 2] << 8 | p[arg - 1];
230
231 if (!EVP_CIPHER_CTX_is_encrypting(ctx)) {
232 if (len < MD5_DIGEST_LENGTH)
233 return -1;
234 len -= MD5_DIGEST_LENGTH;
235 p[arg - 2] = len >> 8;
236 p[arg - 1] = len;
237 }
238 key->payload_length = len;
239 key->md = key->head;
240 MD5_Update(&key->md, p, arg);
241
242 return MD5_DIGEST_LENGTH;
243 }
244 default:
245 return -1;
246 }
247 }
248
249 static EVP_CIPHER r4_hmac_md5_cipher = {
250 # ifdef NID_rc4_hmac_md5
251 NID_rc4_hmac_md5,
252 # else
253 NID_undef,
254 # endif
255 1, EVP_RC4_KEY_SIZE, 0,
256 EVP_CIPH_STREAM_CIPHER | EVP_CIPH_VARIABLE_LENGTH |
257 EVP_CIPH_FLAG_AEAD_CIPHER,
258 EVP_ORIG_GLOBAL,
259 rc4_hmac_md5_init_key,
260 rc4_hmac_md5_cipher,
261 NULL,
262 sizeof(EVP_RC4_HMAC_MD5),
263 NULL,
264 NULL,
265 rc4_hmac_md5_ctrl,
266 NULL
267 };
268
EVP_rc4_hmac_md5(void)269 const EVP_CIPHER *EVP_rc4_hmac_md5(void)
270 {
271 return &r4_hmac_md5_cipher;
272 }
273 #endif
274
