1 /* $OpenBSD: ssl_asn1.c,v 1.69 2024/07/22 14:47:15 jsing Exp $ */
2 /*
3 * Copyright (c) 2016 Joel Sing <jsing@openbsd.org>
4 *
5 * Permission to use, copy, modify, and distribute this software for any
6 * purpose with or without fee is hereby granted, provided that the above
7 * copyright notice and this permission notice appear in all copies.
8 *
9 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16 */
17
18 #include <limits.h>
19
20 #include <openssl/ssl.h>
21 #include <openssl/x509.h>
22
23 #include "bytestring.h"
24 #include "ssl_local.h"
25
26 #define SSLASN1_TAG (CBS_ASN1_CONSTRUCTED | CBS_ASN1_CONTEXT_SPECIFIC)
27 #define SSLASN1_TIME_TAG (SSLASN1_TAG | 1)
28 #define SSLASN1_TIMEOUT_TAG (SSLASN1_TAG | 2)
29 #define SSLASN1_PEER_CERT_TAG (SSLASN1_TAG | 3)
30 #define SSLASN1_SESSION_ID_CTX_TAG (SSLASN1_TAG | 4)
31 #define SSLASN1_VERIFY_RESULT_TAG (SSLASN1_TAG | 5)
32 #define SSLASN1_HOSTNAME_TAG (SSLASN1_TAG | 6)
33 #define SSLASN1_LIFETIME_TAG (SSLASN1_TAG | 9)
34 #define SSLASN1_TICKET_TAG (SSLASN1_TAG | 10)
35
36 static uint64_t
time_max(void)37 time_max(void)
38 {
39 if (sizeof(time_t) == sizeof(int32_t))
40 return INT32_MAX;
41 if (sizeof(time_t) == sizeof(int64_t))
42 return INT64_MAX;
43 return 0;
44 }
45
46 static int
SSL_SESSION_encode(SSL_SESSION * s,unsigned char ** out,size_t * out_len,int ticket_encoding)47 SSL_SESSION_encode(SSL_SESSION *s, unsigned char **out, size_t *out_len,
48 int ticket_encoding)
49 {
50 CBB cbb, session, cipher_suite, session_id, master_key, time, timeout;
51 CBB peer_cert, sidctx, verify_result, hostname, lifetime, ticket, value;
52 unsigned char *peer_cert_bytes = NULL;
53 int len, rv = 0;
54
55 if (!CBB_init(&cbb, 0))
56 goto err;
57
58 if (!CBB_add_asn1(&cbb, &session, CBS_ASN1_SEQUENCE))
59 goto err;
60
61 /* Session ASN1 version. */
62 if (!CBB_add_asn1_uint64(&session, SSL_SESSION_ASN1_VERSION))
63 goto err;
64
65 /* TLS/SSL protocol version. */
66 if (s->ssl_version < 0)
67 goto err;
68 if (!CBB_add_asn1_uint64(&session, s->ssl_version))
69 goto err;
70
71 /* Cipher suite value. */
72 if (!CBB_add_asn1(&session, &cipher_suite, CBS_ASN1_OCTETSTRING))
73 goto err;
74 if (!CBB_add_u16(&cipher_suite, s->cipher_value))
75 goto err;
76
77 /* Session ID - zero length for a ticket. */
78 if (!CBB_add_asn1(&session, &session_id, CBS_ASN1_OCTETSTRING))
79 goto err;
80 if (!CBB_add_bytes(&session_id, s->session_id,
81 ticket_encoding ? 0 : s->session_id_length))
82 goto err;
83
84 /* Master key. */
85 if (!CBB_add_asn1(&session, &master_key, CBS_ASN1_OCTETSTRING))
86 goto err;
87 if (!CBB_add_bytes(&master_key, s->master_key, s->master_key_length))
88 goto err;
89
90 /* Time [1]. */
91 if (s->time != 0) {
92 if (s->time < 0)
93 goto err;
94 if (!CBB_add_asn1(&session, &time, SSLASN1_TIME_TAG))
95 goto err;
96 if (!CBB_add_asn1_uint64(&time, s->time))
97 goto err;
98 }
99
100 /* Timeout [2]. */
101 if (s->timeout != 0) {
102 if (s->timeout < 0)
103 goto err;
104 if (!CBB_add_asn1(&session, &timeout, SSLASN1_TIMEOUT_TAG))
105 goto err;
106 if (!CBB_add_asn1_uint64(&timeout, s->timeout))
107 goto err;
108 }
109
110 /* Peer certificate [3]. */
111 if (s->peer_cert != NULL) {
112 if ((len = i2d_X509(s->peer_cert, &peer_cert_bytes)) <= 0)
113 goto err;
114 if (!CBB_add_asn1(&session, &peer_cert, SSLASN1_PEER_CERT_TAG))
115 goto err;
116 if (!CBB_add_bytes(&peer_cert, peer_cert_bytes, len))
117 goto err;
118 }
119
120 /* Session ID context [4]. */
121 /* XXX - Actually handle this as optional? */
122 if (!CBB_add_asn1(&session, &sidctx, SSLASN1_SESSION_ID_CTX_TAG))
123 goto err;
124 if (!CBB_add_asn1(&sidctx, &value, CBS_ASN1_OCTETSTRING))
125 goto err;
126 if (!CBB_add_bytes(&value, s->sid_ctx, s->sid_ctx_length))
127 goto err;
128
129 /* Verify result [5]. */
130 if (s->verify_result != X509_V_OK) {
131 if (s->verify_result < 0)
132 goto err;
133 if (!CBB_add_asn1(&session, &verify_result,
134 SSLASN1_VERIFY_RESULT_TAG))
135 goto err;
136 if (!CBB_add_asn1_uint64(&verify_result, s->verify_result))
137 goto err;
138 }
139
140 /* Hostname [6]. */
141 if (s->tlsext_hostname != NULL) {
142 if (!CBB_add_asn1(&session, &hostname, SSLASN1_HOSTNAME_TAG))
143 goto err;
144 if (!CBB_add_asn1(&hostname, &value, CBS_ASN1_OCTETSTRING))
145 goto err;
146 if (!CBB_add_bytes(&value, (const uint8_t *)s->tlsext_hostname,
147 strlen(s->tlsext_hostname)))
148 goto err;
149 }
150
151 /* PSK identity hint [7]. */
152 /* PSK identity [8]. */
153
154 /* Ticket lifetime hint [9]. */
155 if (s->tlsext_tick_lifetime_hint > 0) {
156 if (!CBB_add_asn1(&session, &lifetime, SSLASN1_LIFETIME_TAG))
157 goto err;
158 if (!CBB_add_asn1_uint64(&lifetime,
159 s->tlsext_tick_lifetime_hint))
160 goto err;
161 }
162
163 /* Ticket [10]. */
164 if (s->tlsext_tick != NULL) {
165 if (!CBB_add_asn1(&session, &ticket, SSLASN1_TICKET_TAG))
166 goto err;
167 if (!CBB_add_asn1(&ticket, &value, CBS_ASN1_OCTETSTRING))
168 goto err;
169 if (!CBB_add_bytes(&value, s->tlsext_tick, s->tlsext_ticklen))
170 goto err;
171 }
172
173 /* Compression method [11]. */
174 /* SRP username [12]. */
175
176 if (!CBB_finish(&cbb, out, out_len))
177 goto err;
178
179 rv = 1;
180
181 err:
182 CBB_cleanup(&cbb);
183 free(peer_cert_bytes);
184
185 return rv;
186 }
187
188 int
SSL_SESSION_ticket(SSL_SESSION * ss,unsigned char ** out,size_t * out_len)189 SSL_SESSION_ticket(SSL_SESSION *ss, unsigned char **out, size_t *out_len)
190 {
191 if (ss == NULL)
192 return 0;
193
194 if (ss->cipher_value == 0)
195 return 0;
196
197 return SSL_SESSION_encode(ss, out, out_len, 1);
198 }
199
200 int
i2d_SSL_SESSION(SSL_SESSION * ss,unsigned char ** pp)201 i2d_SSL_SESSION(SSL_SESSION *ss, unsigned char **pp)
202 {
203 unsigned char *data = NULL;
204 size_t data_len = 0;
205 int rv = -1;
206
207 if (ss == NULL)
208 return 0;
209
210 if (ss->cipher_value == 0)
211 return 0;
212
213 if (!SSL_SESSION_encode(ss, &data, &data_len, 0))
214 goto err;
215
216 if (data_len > INT_MAX)
217 goto err;
218
219 if (pp != NULL) {
220 if (*pp == NULL) {
221 *pp = data;
222 data = NULL;
223 } else {
224 memcpy(*pp, data, data_len);
225 *pp += data_len;
226 }
227 }
228
229 rv = (int)data_len;
230
231 err:
232 freezero(data, data_len);
233
234 return rv;
235 }
236 LSSL_ALIAS(i2d_SSL_SESSION);
237
238 SSL_SESSION *
d2i_SSL_SESSION(SSL_SESSION ** a,const unsigned char ** pp,long length)239 d2i_SSL_SESSION(SSL_SESSION **a, const unsigned char **pp, long length)
240 {
241 CBS cbs, session, cipher_suite, session_id, master_key, peer_cert;
242 CBS hostname, ticket;
243 uint64_t version, tls_version, stime, timeout, verify_result, lifetime;
244 const unsigned char *peer_cert_bytes;
245 SSL_SESSION *s = NULL;
246 size_t data_len;
247 int present;
248
249 if (a != NULL)
250 s = *a;
251
252 if (s == NULL) {
253 if ((s = SSL_SESSION_new()) == NULL) {
254 SSLerrorx(ERR_R_MALLOC_FAILURE);
255 return (NULL);
256 }
257 }
258
259 CBS_init(&cbs, *pp, length);
260
261 if (!CBS_get_asn1(&cbs, &session, CBS_ASN1_SEQUENCE))
262 goto err;
263
264 /* Session ASN1 version. */
265 if (!CBS_get_asn1_uint64(&session, &version))
266 goto err;
267 if (version != SSL_SESSION_ASN1_VERSION)
268 goto err;
269
270 /* TLS/SSL Protocol Version. */
271 if (!CBS_get_asn1_uint64(&session, &tls_version))
272 goto err;
273 if (tls_version > INT_MAX)
274 goto err;
275 s->ssl_version = (int)tls_version;
276
277 /* Cipher suite value. */
278 if (!CBS_get_asn1(&session, &cipher_suite, CBS_ASN1_OCTETSTRING))
279 goto err;
280 if (!CBS_get_u16(&cipher_suite, &s->cipher_value))
281 goto err;
282 if (CBS_len(&cipher_suite) != 0)
283 goto err;
284
285 /* Session ID. */
286 if (!CBS_get_asn1(&session, &session_id, CBS_ASN1_OCTETSTRING))
287 goto err;
288 if (!CBS_write_bytes(&session_id, s->session_id, sizeof(s->session_id),
289 &s->session_id_length))
290 goto err;
291
292 /* Master key. */
293 if (!CBS_get_asn1(&session, &master_key, CBS_ASN1_OCTETSTRING))
294 goto err;
295 if (!CBS_write_bytes(&master_key, s->master_key, sizeof(s->master_key),
296 &s->master_key_length))
297 goto err;
298
299 /* Time [1]. */
300 s->time = time(NULL);
301 if (!CBS_get_optional_asn1_uint64(&session, &stime, SSLASN1_TIME_TAG,
302 0))
303 goto err;
304 if (stime > time_max())
305 goto err;
306 if (stime != 0)
307 s->time = (time_t)stime;
308
309 /* Timeout [2]. */
310 s->timeout = 3;
311 if (!CBS_get_optional_asn1_uint64(&session, &timeout,
312 SSLASN1_TIMEOUT_TAG, 0))
313 goto err;
314 if (timeout > LONG_MAX)
315 goto err;
316 if (timeout != 0)
317 s->timeout = (long)timeout;
318
319 /* Peer certificate [3]. */
320 X509_free(s->peer_cert);
321 s->peer_cert = NULL;
322 if (!CBS_get_optional_asn1(&session, &peer_cert, &present,
323 SSLASN1_PEER_CERT_TAG))
324 goto err;
325 if (present) {
326 data_len = CBS_len(&peer_cert);
327 if (data_len > LONG_MAX)
328 goto err;
329 peer_cert_bytes = CBS_data(&peer_cert);
330 if (d2i_X509(&s->peer_cert, &peer_cert_bytes,
331 (long)data_len) == NULL)
332 goto err;
333 }
334
335 /* Session ID context [4]. */
336 s->sid_ctx_length = 0;
337 if (!CBS_get_optional_asn1_octet_string(&session, &session_id, &present,
338 SSLASN1_SESSION_ID_CTX_TAG))
339 goto err;
340 if (present) {
341 if (!CBS_write_bytes(&session_id, (uint8_t *)&s->sid_ctx,
342 sizeof(s->sid_ctx), &s->sid_ctx_length))
343 goto err;
344 }
345
346 /* Verify result [5]. */
347 s->verify_result = X509_V_OK;
348 if (!CBS_get_optional_asn1_uint64(&session, &verify_result,
349 SSLASN1_VERIFY_RESULT_TAG, X509_V_OK))
350 goto err;
351 if (verify_result > LONG_MAX)
352 goto err;
353 s->verify_result = (long)verify_result;
354
355 /* Hostname [6]. */
356 free(s->tlsext_hostname);
357 s->tlsext_hostname = NULL;
358 if (!CBS_get_optional_asn1_octet_string(&session, &hostname, &present,
359 SSLASN1_HOSTNAME_TAG))
360 goto err;
361 if (present) {
362 if (CBS_contains_zero_byte(&hostname))
363 goto err;
364 if (!CBS_strdup(&hostname, &s->tlsext_hostname))
365 goto err;
366 }
367
368 /* PSK identity hint [7]. */
369 /* PSK identity [8]. */
370
371 /* Ticket lifetime [9]. */
372 s->tlsext_tick_lifetime_hint = 0;
373 if (!CBS_get_optional_asn1_uint64(&session, &lifetime,
374 SSLASN1_LIFETIME_TAG, 0))
375 goto err;
376 if (lifetime > UINT32_MAX)
377 goto err;
378 if (lifetime > 0)
379 s->tlsext_tick_lifetime_hint = (uint32_t)lifetime;
380
381 /* Ticket [10]. */
382 free(s->tlsext_tick);
383 s->tlsext_tick = NULL;
384 if (!CBS_get_optional_asn1_octet_string(&session, &ticket, &present,
385 SSLASN1_TICKET_TAG))
386 goto err;
387 if (present) {
388 if (!CBS_stow(&ticket, &s->tlsext_tick, &s->tlsext_ticklen))
389 goto err;
390 }
391
392 /* Compression method [11]. */
393 /* SRP username [12]. */
394
395 *pp = CBS_data(&cbs);
396
397 if (a != NULL)
398 *a = s;
399
400 return (s);
401
402 err:
403 ERR_asprintf_error_data("offset=%d", (int)(CBS_data(&cbs) - *pp));
404
405 if (s != NULL && (a == NULL || *a != s))
406 SSL_SESSION_free(s);
407
408 return (NULL);
409 }
410 LSSL_ALIAS(d2i_SSL_SESSION);
411