1 /*
2 * Copyright 2018-2022 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 #include "ssl_local.h"
11 #include "internal/ktls.h"
12
13 #ifndef OPENSSL_NO_KTLS_RX
14 /*
15 * Count the number of records that were not processed yet from record boundary.
16 *
17 * This function assumes that there are only fully formed records read in the
18 * record layer. If read_ahead is enabled, then this might be false and this
19 * function will fail.
20 */
count_unprocessed_records(SSL * s)21 static int count_unprocessed_records(SSL *s)
22 {
23 SSL3_BUFFER *rbuf = RECORD_LAYER_get_rbuf(&s->rlayer);
24 PACKET pkt, subpkt;
25 int count = 0;
26
27 if (!PACKET_buf_init(&pkt, rbuf->buf + rbuf->offset, rbuf->left))
28 return -1;
29
30 while (PACKET_remaining(&pkt) > 0) {
31 /* Skip record type and version */
32 if (!PACKET_forward(&pkt, 3))
33 return -1;
34
35 /* Read until next record */
36 if (!PACKET_get_length_prefixed_2(&pkt, &subpkt))
37 return -1;
38
39 count += 1;
40 }
41
42 return count;
43 }
44
45 /*
46 * The kernel cannot offload receive if a partial TLS record has been read.
47 * Check the read buffer for unprocessed records. If the buffer contains a
48 * partial record, fail and return 0. Otherwise, update the sequence
49 * number at *rec_seq for the count of unprocessed records and return 1.
50 */
check_rx_read_ahead(SSL * s,unsigned char * rec_seq)51 static int check_rx_read_ahead(SSL *s, unsigned char *rec_seq)
52 {
53 int bit, count_unprocessed;
54
55 count_unprocessed = count_unprocessed_records(s);
56 if (count_unprocessed < 0)
57 return 0;
58
59 /* increment the crypto_info record sequence */
60 while (count_unprocessed) {
61 for (bit = 7; bit >= 0; bit--) { /* increment */
62 ++rec_seq[bit];
63 if (rec_seq[bit] != 0)
64 break;
65 }
66 count_unprocessed--;
67
68 }
69
70 return 1;
71 }
72 #endif
73
74 #if defined(__FreeBSD__)
75 # include "crypto/cryptodev.h"
76
77 /*-
78 * Check if a given cipher is supported by the KTLS interface.
79 * The kernel might still fail the setsockopt() if no suitable
80 * provider is found, but this checks if the socket option
81 * supports the cipher suite used at all.
82 */
ktls_check_supported_cipher(const SSL * s,const EVP_CIPHER * c,const EVP_CIPHER_CTX * dd)83 int ktls_check_supported_cipher(const SSL *s, const EVP_CIPHER *c,
84 const EVP_CIPHER_CTX *dd)
85 {
86
87 switch (s->version) {
88 case TLS1_VERSION:
89 case TLS1_1_VERSION:
90 case TLS1_2_VERSION:
91 case TLS1_3_VERSION:
92 break;
93 default:
94 return 0;
95 }
96
97 switch (s->s3.tmp.new_cipher->algorithm_enc) {
98 case SSL_AES128GCM:
99 case SSL_AES256GCM:
100 return 1;
101 # ifdef OPENSSL_KTLS_CHACHA20_POLY1305
102 case SSL_CHACHA20POLY1305:
103 return 1;
104 # endif
105 case SSL_AES128:
106 case SSL_AES256:
107 if (s->ext.use_etm)
108 return 0;
109 switch (s->s3.tmp.new_cipher->algorithm_mac) {
110 case SSL_SHA1:
111 case SSL_SHA256:
112 case SSL_SHA384:
113 return 1;
114 default:
115 return 0;
116 }
117 default:
118 return 0;
119 }
120 }
121
122 /* Function to configure kernel TLS structure */
ktls_configure_crypto(SSL * s,const EVP_CIPHER * c,EVP_CIPHER_CTX * dd,void * rl_sequence,ktls_crypto_info_t * crypto_info,int is_tx,unsigned char * iv,unsigned char * key,unsigned char * mac_key,size_t mac_secret_size)123 int ktls_configure_crypto(SSL *s, const EVP_CIPHER *c, EVP_CIPHER_CTX *dd,
124 void *rl_sequence, ktls_crypto_info_t *crypto_info,
125 int is_tx, unsigned char *iv,
126 unsigned char *key, unsigned char *mac_key,
127 size_t mac_secret_size)
128 {
129 memset(crypto_info, 0, sizeof(*crypto_info));
130 switch (s->s3.tmp.new_cipher->algorithm_enc) {
131 case SSL_AES128GCM:
132 case SSL_AES256GCM:
133 crypto_info->cipher_algorithm = CRYPTO_AES_NIST_GCM_16;
134 if (s->version == TLS1_3_VERSION) {
135 crypto_info->iv_len = EVP_CIPHER_CTX_get_iv_length(dd);
136 if (crypto_info->iv_len < 0)
137 return 0;
138 }
139 else
140 crypto_info->iv_len = EVP_GCM_TLS_FIXED_IV_LEN;
141 break;
142 # ifdef OPENSSL_KTLS_CHACHA20_POLY1305
143 case SSL_CHACHA20POLY1305:
144 crypto_info->cipher_algorithm = CRYPTO_CHACHA20_POLY1305;
145 crypto_info->iv_len = EVP_CIPHER_CTX_get_iv_length(dd);
146 break;
147 # endif
148 case SSL_AES128:
149 case SSL_AES256:
150 switch (s->s3.tmp.new_cipher->algorithm_mac) {
151 case SSL_SHA1:
152 crypto_info->auth_algorithm = CRYPTO_SHA1_HMAC;
153 break;
154 case SSL_SHA256:
155 crypto_info->auth_algorithm = CRYPTO_SHA2_256_HMAC;
156 break;
157 case SSL_SHA384:
158 crypto_info->auth_algorithm = CRYPTO_SHA2_384_HMAC;
159 break;
160 default:
161 return 0;
162 }
163 crypto_info->cipher_algorithm = CRYPTO_AES_CBC;
164 crypto_info->iv_len = EVP_CIPHER_get_iv_length(c);
165 crypto_info->auth_key = mac_key;
166 crypto_info->auth_key_len = mac_secret_size;
167 break;
168 default:
169 return 0;
170 }
171 crypto_info->cipher_key = key;
172 crypto_info->cipher_key_len = EVP_CIPHER_get_key_length(c);
173 crypto_info->iv = iv;
174 crypto_info->tls_vmajor = (s->version >> 8) & 0x000000ff;
175 crypto_info->tls_vminor = (s->version & 0x000000ff);
176 # ifdef TCP_RXTLS_ENABLE
177 memcpy(crypto_info->rec_seq, rl_sequence, sizeof(crypto_info->rec_seq));
178 if (!is_tx && !check_rx_read_ahead(s, crypto_info->rec_seq))
179 return 0;
180 # else
181 if (!is_tx)
182 return 0;
183 # endif
184 return 1;
185 };
186
187 #endif /* __FreeBSD__ */
188
189 #if defined(OPENSSL_SYS_LINUX)
190
191 /* Function to check supported ciphers in Linux */
ktls_check_supported_cipher(const SSL * s,const EVP_CIPHER * c,const EVP_CIPHER_CTX * dd)192 int ktls_check_supported_cipher(const SSL *s, const EVP_CIPHER *c,
193 const EVP_CIPHER_CTX *dd)
194 {
195 switch (s->version) {
196 case TLS1_2_VERSION:
197 case TLS1_3_VERSION:
198 break;
199 default:
200 return 0;
201 }
202
203 /* check that cipher is AES_GCM_128, AES_GCM_256, AES_CCM_128
204 * or Chacha20-Poly1305
205 */
206 # ifdef OPENSSL_KTLS_AES_CCM_128
207 if (EVP_CIPHER_is_a(c, "AES-128-CCM")) {
208 if (s->version == TLS_1_3_VERSION /* broken on 5.x kernels */
209 || EVP_CIPHER_CTX_get_tag_length(dd) != EVP_CCM_TLS_TAG_LEN)
210 return 0;
211 return 1;
212 } else
213 # endif
214 if (0
215 # ifdef OPENSSL_KTLS_AES_GCM_128
216 || EVP_CIPHER_is_a(c, "AES-128-GCM")
217 # endif
218 # ifdef OPENSSL_KTLS_AES_GCM_256
219 || EVP_CIPHER_is_a(c, "AES-256-GCM")
220 # endif
221 # ifdef OPENSSL_KTLS_CHACHA20_POLY1305
222 || EVP_CIPHER_is_a(c, "ChaCha20-Poly1305")
223 # endif
224 ) {
225 return 1;
226 }
227 return 0;
228 }
229
230 /* Function to configure kernel TLS structure */
ktls_configure_crypto(SSL * s,const EVP_CIPHER * c,EVP_CIPHER_CTX * dd,void * rl_sequence,ktls_crypto_info_t * crypto_info,int is_tx,unsigned char * iv,unsigned char * key,unsigned char * mac_key,size_t mac_secret_size)231 int ktls_configure_crypto(SSL *s, const EVP_CIPHER *c, EVP_CIPHER_CTX *dd,
232 void *rl_sequence, ktls_crypto_info_t *crypto_info,
233 int is_tx, unsigned char *iv,
234 unsigned char *key, unsigned char *mac_key,
235 size_t mac_secret_size)
236 {
237 unsigned char geniv[12];
238 unsigned char *iiv = iv;
239
240 # ifdef OPENSSL_NO_KTLS_RX
241 if (!is_tx)
242 return 0;
243 # endif
244
245 if (s->version == TLS1_2_VERSION &&
246 EVP_CIPHER_get_mode(c) == EVP_CIPH_GCM_MODE) {
247 if (!EVP_CIPHER_CTX_get_updated_iv(dd, geniv,
248 EVP_GCM_TLS_FIXED_IV_LEN
249 + EVP_GCM_TLS_EXPLICIT_IV_LEN))
250 return 0;
251 iiv = geniv;
252 }
253
254 memset(crypto_info, 0, sizeof(*crypto_info));
255 switch (EVP_CIPHER_get_nid(c))
256 {
257 # ifdef OPENSSL_KTLS_AES_GCM_128
258 case NID_aes_128_gcm:
259 crypto_info->gcm128.info.cipher_type = TLS_CIPHER_AES_GCM_128;
260 crypto_info->gcm128.info.version = s->version;
261 crypto_info->tls_crypto_info_len = sizeof(crypto_info->gcm128);
262 memcpy(crypto_info->gcm128.iv, iiv + EVP_GCM_TLS_FIXED_IV_LEN,
263 TLS_CIPHER_AES_GCM_128_IV_SIZE);
264 memcpy(crypto_info->gcm128.salt, iiv, TLS_CIPHER_AES_GCM_128_SALT_SIZE);
265 memcpy(crypto_info->gcm128.key, key, EVP_CIPHER_get_key_length(c));
266 memcpy(crypto_info->gcm128.rec_seq, rl_sequence,
267 TLS_CIPHER_AES_GCM_128_REC_SEQ_SIZE);
268 if (!is_tx && !check_rx_read_ahead(s, crypto_info->gcm128.rec_seq))
269 return 0;
270 return 1;
271 # endif
272 # ifdef OPENSSL_KTLS_AES_GCM_256
273 case NID_aes_256_gcm:
274 crypto_info->gcm256.info.cipher_type = TLS_CIPHER_AES_GCM_256;
275 crypto_info->gcm256.info.version = s->version;
276 crypto_info->tls_crypto_info_len = sizeof(crypto_info->gcm256);
277 memcpy(crypto_info->gcm256.iv, iiv + EVP_GCM_TLS_FIXED_IV_LEN,
278 TLS_CIPHER_AES_GCM_256_IV_SIZE);
279 memcpy(crypto_info->gcm256.salt, iiv, TLS_CIPHER_AES_GCM_256_SALT_SIZE);
280 memcpy(crypto_info->gcm256.key, key, EVP_CIPHER_get_key_length(c));
281 memcpy(crypto_info->gcm256.rec_seq, rl_sequence,
282 TLS_CIPHER_AES_GCM_256_REC_SEQ_SIZE);
283 if (!is_tx && !check_rx_read_ahead(s, crypto_info->gcm256.rec_seq))
284 return 0;
285 return 1;
286 # endif
287 # ifdef OPENSSL_KTLS_AES_CCM_128
288 case NID_aes_128_ccm:
289 crypto_info->ccm128.info.cipher_type = TLS_CIPHER_AES_CCM_128;
290 crypto_info->ccm128.info.version = s->version;
291 crypto_info->tls_crypto_info_len = sizeof(crypto_info->ccm128);
292 memcpy(crypto_info->ccm128.iv, iiv + EVP_CCM_TLS_FIXED_IV_LEN,
293 TLS_CIPHER_AES_CCM_128_IV_SIZE);
294 memcpy(crypto_info->ccm128.salt, iiv, TLS_CIPHER_AES_CCM_128_SALT_SIZE);
295 memcpy(crypto_info->ccm128.key, key, EVP_CIPHER_get_key_length(c));
296 memcpy(crypto_info->ccm128.rec_seq, rl_sequence,
297 TLS_CIPHER_AES_CCM_128_REC_SEQ_SIZE);
298 if (!is_tx && !check_rx_read_ahead(s, crypto_info->ccm128.rec_seq))
299 return 0;
300 return 1;
301 # endif
302 # ifdef OPENSSL_KTLS_CHACHA20_POLY1305
303 case NID_chacha20_poly1305:
304 crypto_info->chacha20poly1305.info.cipher_type = TLS_CIPHER_CHACHA20_POLY1305;
305 crypto_info->chacha20poly1305.info.version = s->version;
306 crypto_info->tls_crypto_info_len = sizeof(crypto_info->chacha20poly1305);
307 memcpy(crypto_info->chacha20poly1305.iv, iiv,
308 TLS_CIPHER_CHACHA20_POLY1305_IV_SIZE);
309 memcpy(crypto_info->chacha20poly1305.key, key,
310 EVP_CIPHER_get_key_length(c));
311 memcpy(crypto_info->chacha20poly1305.rec_seq, rl_sequence,
312 TLS_CIPHER_CHACHA20_POLY1305_REC_SEQ_SIZE);
313 if (!is_tx
314 && !check_rx_read_ahead(s,
315 crypto_info->chacha20poly1305.rec_seq))
316 return 0;
317 return 1;
318 # endif
319 default:
320 return 0;
321 }
322
323 }
324
325 #endif /* OPENSSL_SYS_LINUX */
326