xref: /freebsd/crypto/openssl/ssl/s3_enc.c (revision e7be843b4a162e68651d3911f0357ed464915629)
1 /*
2  * Copyright 1995-2025 The OpenSSL Project Authors. All Rights Reserved.
3  * Copyright 2005 Nokia. All rights reserved.
4  *
5  * Licensed under the Apache License 2.0 (the "License").  You may not use
6  * this file except in compliance with the License.  You can obtain a copy
7  * in the file LICENSE in the source distribution or at
8  * https://www.openssl.org/source/license.html
9  */
10 
11 #include <stdio.h>
12 #include "ssl_local.h"
13 #include <openssl/evp.h>
14 #include <openssl/md5.h>
15 #include <openssl/core_names.h>
16 #include "internal/cryptlib.h"
17 #include "internal/ssl_unwrap.h"
18 
ssl3_generate_key_block(SSL_CONNECTION * s,unsigned char * km,int num)19 static int ssl3_generate_key_block(SSL_CONNECTION *s, unsigned char *km, int num)
20 {
21     const EVP_MD *md5 = NULL, *sha1 = NULL;
22     EVP_MD_CTX *m5;
23     EVP_MD_CTX *s1;
24     unsigned char buf[16], smd[SHA_DIGEST_LENGTH];
25     unsigned char c = 'A';
26     unsigned int i, k;
27     int ret = 0;
28     SSL_CTX *sctx = SSL_CONNECTION_GET_CTX(s);
29 
30 #ifdef CHARSET_EBCDIC
31     c = os_toascii[c];          /* 'A' in ASCII */
32 #endif
33     k = 0;
34     md5 = ssl_evp_md_fetch(sctx->libctx, NID_md5, sctx->propq);
35     sha1 = ssl_evp_md_fetch(sctx->libctx, NID_sha1, sctx->propq);
36     m5 = EVP_MD_CTX_new();
37     s1 = EVP_MD_CTX_new();
38     if (md5 == NULL || sha1 == NULL || m5 == NULL || s1 == NULL) {
39         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB);
40         goto err;
41     }
42     for (i = 0; (int)i < num; i += MD5_DIGEST_LENGTH) {
43         k++;
44         if (k > sizeof(buf)) {
45             /* bug: 'buf' is too small for this ciphersuite */
46             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
47             goto err;
48         }
49 
50         memset(buf, c, k);
51         c++;
52         if (!EVP_DigestInit_ex(s1, sha1, NULL)
53             || !EVP_DigestUpdate(s1, buf, k)
54             || !EVP_DigestUpdate(s1, s->session->master_key,
55                                  s->session->master_key_length)
56             || !EVP_DigestUpdate(s1, s->s3.server_random, SSL3_RANDOM_SIZE)
57             || !EVP_DigestUpdate(s1, s->s3.client_random, SSL3_RANDOM_SIZE)
58             || !EVP_DigestFinal_ex(s1, smd, NULL)
59             || !EVP_DigestInit_ex(m5, md5, NULL)
60             || !EVP_DigestUpdate(m5, s->session->master_key,
61                                  s->session->master_key_length)
62             || !EVP_DigestUpdate(m5, smd, SHA_DIGEST_LENGTH)) {
63             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
64             goto err;
65         }
66         if ((int)(i + MD5_DIGEST_LENGTH) > num) {
67             if (!EVP_DigestFinal_ex(m5, smd, NULL)) {
68                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
69                 goto err;
70             }
71             memcpy(km, smd, (num - i));
72         } else {
73             if (!EVP_DigestFinal_ex(m5, km, NULL)) {
74                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
75                 goto err;
76             }
77         }
78 
79         km += MD5_DIGEST_LENGTH;
80     }
81     OPENSSL_cleanse(smd, sizeof(smd));
82     ret = 1;
83  err:
84     EVP_MD_CTX_free(m5);
85     EVP_MD_CTX_free(s1);
86     ssl_evp_md_free(md5);
87     ssl_evp_md_free(sha1);
88     return ret;
89 }
90 
ssl3_change_cipher_state(SSL_CONNECTION * s,int which)91 int ssl3_change_cipher_state(SSL_CONNECTION *s, int which)
92 {
93     unsigned char *p, *mac_secret;
94     size_t md_len;
95     unsigned char *key, *iv;
96     const EVP_CIPHER *ciph;
97     const SSL_COMP *comp = NULL;
98     const EVP_MD *md;
99     int mdi;
100     size_t n, iv_len, key_len;
101     int direction = (which & SSL3_CC_READ) != 0 ? OSSL_RECORD_DIRECTION_READ
102                                                 : OSSL_RECORD_DIRECTION_WRITE;
103 
104     ciph = s->s3.tmp.new_sym_enc;
105     md = s->s3.tmp.new_hash;
106     /* m == NULL will lead to a crash later */
107     if (!ossl_assert(md != NULL)) {
108         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
109         goto err;
110     }
111 #ifndef OPENSSL_NO_COMP
112     comp = s->s3.tmp.new_compression;
113 #endif
114 
115     p = s->s3.tmp.key_block;
116     mdi = EVP_MD_get_size(md);
117     if (mdi <= 0) {
118         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
119         goto err;
120     }
121     md_len = (size_t)mdi;
122     key_len = EVP_CIPHER_get_key_length(ciph);
123     iv_len = EVP_CIPHER_get_iv_length(ciph);
124 
125     if ((which == SSL3_CHANGE_CIPHER_CLIENT_WRITE) ||
126         (which == SSL3_CHANGE_CIPHER_SERVER_READ)) {
127         mac_secret = &(p[0]);
128         n = md_len + md_len;
129         key = &(p[n]);
130         n += key_len + key_len;
131         iv = &(p[n]);
132         n += iv_len + iv_len;
133     } else {
134         n = md_len;
135         mac_secret = &(p[n]);
136         n += md_len + key_len;
137         key = &(p[n]);
138         n += key_len + iv_len;
139         iv = &(p[n]);
140         n += iv_len;
141     }
142 
143     if (n > s->s3.tmp.key_block_length) {
144         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
145         goto err;
146     }
147 
148     if (!ssl_set_new_record_layer(s, SSL3_VERSION,
149                                   direction,
150                                   OSSL_RECORD_PROTECTION_LEVEL_APPLICATION,
151                                   NULL, 0, key, key_len, iv, iv_len, mac_secret,
152                                   md_len, ciph, 0, NID_undef, md, comp, NULL)) {
153         /* SSLfatal already called */
154         goto err;
155     }
156 
157     return 1;
158  err:
159     return 0;
160 }
161 
ssl3_setup_key_block(SSL_CONNECTION * s)162 int ssl3_setup_key_block(SSL_CONNECTION *s)
163 {
164     unsigned char *p;
165     const EVP_CIPHER *c;
166     const EVP_MD *hash;
167     int num;
168     int ret = 0;
169     SSL_COMP *comp;
170 
171     if (s->s3.tmp.key_block_length != 0)
172         return 1;
173 
174     if (!ssl_cipher_get_evp(SSL_CONNECTION_GET_CTX(s), s->session, &c, &hash,
175                             NULL, NULL, &comp, 0)) {
176         /* Error is already recorded */
177         SSLfatal_alert(s, SSL_AD_INTERNAL_ERROR);
178         return 0;
179     }
180 
181     ssl_evp_cipher_free(s->s3.tmp.new_sym_enc);
182     s->s3.tmp.new_sym_enc = c;
183     ssl_evp_md_free(s->s3.tmp.new_hash);
184     s->s3.tmp.new_hash = hash;
185 #ifdef OPENSSL_NO_COMP
186     s->s3.tmp.new_compression = NULL;
187 #else
188     s->s3.tmp.new_compression = comp;
189 #endif
190 
191     num = EVP_MD_get_size(hash);
192     if (num <= 0)
193         return 0;
194 
195     num = EVP_CIPHER_get_key_length(c) + num + EVP_CIPHER_get_iv_length(c);
196     num *= 2;
197 
198     ssl3_cleanup_key_block(s);
199 
200     if ((p = OPENSSL_malloc(num)) == NULL) {
201         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_CRYPTO_LIB);
202         return 0;
203     }
204 
205     s->s3.tmp.key_block_length = num;
206     s->s3.tmp.key_block = p;
207 
208     /* Calls SSLfatal() as required */
209     ret = ssl3_generate_key_block(s, p, num);
210 
211     return ret;
212 }
213 
ssl3_cleanup_key_block(SSL_CONNECTION * s)214 void ssl3_cleanup_key_block(SSL_CONNECTION *s)
215 {
216     OPENSSL_clear_free(s->s3.tmp.key_block, s->s3.tmp.key_block_length);
217     s->s3.tmp.key_block = NULL;
218     s->s3.tmp.key_block_length = 0;
219 }
220 
ssl3_init_finished_mac(SSL_CONNECTION * s)221 int ssl3_init_finished_mac(SSL_CONNECTION *s)
222 {
223     BIO *buf = BIO_new(BIO_s_mem());
224 
225     if (buf == NULL) {
226         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_BIO_LIB);
227         return 0;
228     }
229     ssl3_free_digest_list(s);
230     s->s3.handshake_buffer = buf;
231     (void)BIO_set_close(s->s3.handshake_buffer, BIO_CLOSE);
232     return 1;
233 }
234 
235 /*
236  * Free digest list. Also frees handshake buffer since they are always freed
237  * together.
238  */
239 
ssl3_free_digest_list(SSL_CONNECTION * s)240 void ssl3_free_digest_list(SSL_CONNECTION *s)
241 {
242     BIO_free(s->s3.handshake_buffer);
243     s->s3.handshake_buffer = NULL;
244     EVP_MD_CTX_free(s->s3.handshake_dgst);
245     s->s3.handshake_dgst = NULL;
246 }
247 
ssl3_finish_mac(SSL_CONNECTION * s,const unsigned char * buf,size_t len)248 int ssl3_finish_mac(SSL_CONNECTION *s, const unsigned char *buf, size_t len)
249 {
250     int ret;
251 
252     if (s->s3.handshake_dgst == NULL) {
253         /* Note: this writes to a memory BIO so a failure is a fatal error */
254         if (len > INT_MAX) {
255             SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_OVERFLOW_ERROR);
256             return 0;
257         }
258         ret = BIO_write(s->s3.handshake_buffer, (void *)buf, (int)len);
259         if (ret <= 0 || ret != (int)len) {
260             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
261             return 0;
262         }
263     } else {
264         ret = EVP_DigestUpdate(s->s3.handshake_dgst, buf, len);
265         if (!ret) {
266             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
267             return 0;
268         }
269     }
270     return 1;
271 }
272 
ssl3_digest_cached_records(SSL_CONNECTION * s,int keep)273 int ssl3_digest_cached_records(SSL_CONNECTION *s, int keep)
274 {
275     const EVP_MD *md;
276     long hdatalen;
277     void *hdata;
278 
279     if (s->s3.handshake_dgst == NULL) {
280         hdatalen = BIO_get_mem_data(s->s3.handshake_buffer, &hdata);
281         if (hdatalen <= 0) {
282             SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_BAD_HANDSHAKE_LENGTH);
283             return 0;
284         }
285 
286         s->s3.handshake_dgst = EVP_MD_CTX_new();
287         if (s->s3.handshake_dgst == NULL) {
288             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB);
289             return 0;
290         }
291 
292         md = ssl_handshake_md(s);
293         if (md == NULL) {
294             SSLfatal(s, SSL_AD_INTERNAL_ERROR,
295                      SSL_R_NO_SUITABLE_DIGEST_ALGORITHM);
296             return 0;
297         }
298         if (!EVP_DigestInit_ex(s->s3.handshake_dgst, md, NULL)
299             || !EVP_DigestUpdate(s->s3.handshake_dgst, hdata, hdatalen)) {
300             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
301             return 0;
302         }
303     }
304     if (keep == 0) {
305         BIO_free(s->s3.handshake_buffer);
306         s->s3.handshake_buffer = NULL;
307     }
308 
309     return 1;
310 }
311 
ssl3_digest_master_key_set_params(const SSL_SESSION * session,OSSL_PARAM params[])312 void ssl3_digest_master_key_set_params(const SSL_SESSION *session,
313                                        OSSL_PARAM params[])
314 {
315     int n = 0;
316     params[n++] = OSSL_PARAM_construct_octet_string(OSSL_DIGEST_PARAM_SSL3_MS,
317                                                     (void *)session->master_key,
318                                                     session->master_key_length);
319     params[n++] = OSSL_PARAM_construct_end();
320 }
321 
ssl3_final_finish_mac(SSL_CONNECTION * s,const char * sender,size_t len,unsigned char * p)322 size_t ssl3_final_finish_mac(SSL_CONNECTION *s, const char *sender, size_t len,
323                              unsigned char *p)
324 {
325     int ret;
326     EVP_MD_CTX *ctx = NULL;
327 
328     if (!ssl3_digest_cached_records(s, 0)) {
329         /* SSLfatal() already called */
330         return 0;
331     }
332 
333     if (EVP_MD_CTX_get_type(s->s3.handshake_dgst) != NID_md5_sha1) {
334         SSLfatal(s, SSL_AD_INTERNAL_ERROR, SSL_R_NO_REQUIRED_DIGEST);
335         return 0;
336     }
337 
338     ctx = EVP_MD_CTX_new();
339     if (ctx == NULL) {
340         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB);
341         return 0;
342     }
343     if (!EVP_MD_CTX_copy_ex(ctx, s->s3.handshake_dgst)) {
344         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
345         ret = 0;
346         goto err;
347     }
348 
349     ret = EVP_MD_CTX_get_size(ctx);
350     if (ret < 0) {
351         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
352         ret = 0;
353         goto err;
354     }
355 
356     if (sender != NULL) {
357         OSSL_PARAM digest_cmd_params[3];
358 
359         ssl3_digest_master_key_set_params(s->session, digest_cmd_params);
360 
361         if (EVP_DigestUpdate(ctx, sender, len) <= 0
362             || EVP_MD_CTX_set_params(ctx, digest_cmd_params) <= 0
363             || EVP_DigestFinal_ex(ctx, p, NULL) <= 0) {
364                 SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
365                 ret = 0;
366         }
367     }
368 
369  err:
370     EVP_MD_CTX_free(ctx);
371 
372     return ret;
373 }
374 
ssl3_generate_master_secret(SSL_CONNECTION * s,unsigned char * out,unsigned char * p,size_t len,size_t * secret_size)375 int ssl3_generate_master_secret(SSL_CONNECTION *s, unsigned char *out,
376                                 unsigned char *p,
377                                 size_t len, size_t *secret_size)
378 {
379     static const unsigned char *const salt[3] = {
380 #ifndef CHARSET_EBCDIC
381         (const unsigned char *)"A",
382         (const unsigned char *)"BB",
383         (const unsigned char *)"CCC",
384 #else
385         (const unsigned char *)"\x41",
386         (const unsigned char *)"\x42\x42",
387         (const unsigned char *)"\x43\x43\x43",
388 #endif
389     };
390     unsigned char buf[EVP_MAX_MD_SIZE];
391     EVP_MD_CTX *ctx = EVP_MD_CTX_new();
392     int i, ret = 1;
393     unsigned int n;
394     size_t ret_secret_size = 0;
395 
396     if (ctx == NULL) {
397         SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_EVP_LIB);
398         return 0;
399     }
400     for (i = 0; i < 3; i++) {
401         if (EVP_DigestInit_ex(ctx, SSL_CONNECTION_GET_CTX(s)->sha1, NULL) <= 0
402             || EVP_DigestUpdate(ctx, salt[i],
403                                 strlen((const char *)salt[i])) <= 0
404             || EVP_DigestUpdate(ctx, p, len) <= 0
405             || EVP_DigestUpdate(ctx, &(s->s3.client_random[0]),
406                                 SSL3_RANDOM_SIZE) <= 0
407             || EVP_DigestUpdate(ctx, &(s->s3.server_random[0]),
408                                 SSL3_RANDOM_SIZE) <= 0
409             || EVP_DigestFinal_ex(ctx, buf, &n) <= 0
410             || EVP_DigestInit_ex(ctx, SSL_CONNECTION_GET_CTX(s)->md5, NULL) <= 0
411             || EVP_DigestUpdate(ctx, p, len) <= 0
412             || EVP_DigestUpdate(ctx, buf, n) <= 0
413             || EVP_DigestFinal_ex(ctx, out, &n) <= 0) {
414             SSLfatal(s, SSL_AD_INTERNAL_ERROR, ERR_R_INTERNAL_ERROR);
415             ret = 0;
416             break;
417         }
418         out += n;
419         ret_secret_size += n;
420     }
421     EVP_MD_CTX_free(ctx);
422 
423     OPENSSL_cleanse(buf, sizeof(buf));
424     if (ret)
425         *secret_size = ret_secret_size;
426     return ret;
427 }
428 
ssl3_alert_code(int code)429 int ssl3_alert_code(int code)
430 {
431     switch (code) {
432     case SSL_AD_CLOSE_NOTIFY:
433         return SSL3_AD_CLOSE_NOTIFY;
434     case SSL_AD_UNEXPECTED_MESSAGE:
435         return SSL3_AD_UNEXPECTED_MESSAGE;
436     case SSL_AD_BAD_RECORD_MAC:
437         return SSL3_AD_BAD_RECORD_MAC;
438     case SSL_AD_DECRYPTION_FAILED:
439         return SSL3_AD_BAD_RECORD_MAC;
440     case SSL_AD_RECORD_OVERFLOW:
441         return SSL3_AD_BAD_RECORD_MAC;
442     case SSL_AD_DECOMPRESSION_FAILURE:
443         return SSL3_AD_DECOMPRESSION_FAILURE;
444     case SSL_AD_HANDSHAKE_FAILURE:
445         return SSL3_AD_HANDSHAKE_FAILURE;
446     case SSL_AD_NO_CERTIFICATE:
447         return SSL3_AD_NO_CERTIFICATE;
448     case SSL_AD_BAD_CERTIFICATE:
449         return SSL3_AD_BAD_CERTIFICATE;
450     case SSL_AD_UNSUPPORTED_CERTIFICATE:
451         return SSL3_AD_UNSUPPORTED_CERTIFICATE;
452     case SSL_AD_CERTIFICATE_REVOKED:
453         return SSL3_AD_CERTIFICATE_REVOKED;
454     case SSL_AD_CERTIFICATE_EXPIRED:
455         return SSL3_AD_CERTIFICATE_EXPIRED;
456     case SSL_AD_CERTIFICATE_UNKNOWN:
457         return SSL3_AD_CERTIFICATE_UNKNOWN;
458     case SSL_AD_ILLEGAL_PARAMETER:
459         return SSL3_AD_ILLEGAL_PARAMETER;
460     case SSL_AD_UNKNOWN_CA:
461         return SSL3_AD_BAD_CERTIFICATE;
462     case SSL_AD_ACCESS_DENIED:
463         return SSL3_AD_HANDSHAKE_FAILURE;
464     case SSL_AD_DECODE_ERROR:
465         return SSL3_AD_HANDSHAKE_FAILURE;
466     case SSL_AD_DECRYPT_ERROR:
467         return SSL3_AD_HANDSHAKE_FAILURE;
468     case SSL_AD_EXPORT_RESTRICTION:
469         return SSL3_AD_HANDSHAKE_FAILURE;
470     case SSL_AD_PROTOCOL_VERSION:
471         return SSL3_AD_HANDSHAKE_FAILURE;
472     case SSL_AD_INSUFFICIENT_SECURITY:
473         return SSL3_AD_HANDSHAKE_FAILURE;
474     case SSL_AD_INTERNAL_ERROR:
475         return SSL3_AD_HANDSHAKE_FAILURE;
476     case SSL_AD_USER_CANCELLED:
477         return SSL3_AD_HANDSHAKE_FAILURE;
478     case SSL_AD_NO_RENEGOTIATION:
479         return -1;            /* Don't send it :-) */
480     case SSL_AD_UNSUPPORTED_EXTENSION:
481         return SSL3_AD_HANDSHAKE_FAILURE;
482     case SSL_AD_CERTIFICATE_UNOBTAINABLE:
483         return SSL3_AD_HANDSHAKE_FAILURE;
484     case SSL_AD_UNRECOGNIZED_NAME:
485         return SSL3_AD_HANDSHAKE_FAILURE;
486     case SSL_AD_BAD_CERTIFICATE_STATUS_RESPONSE:
487         return SSL3_AD_HANDSHAKE_FAILURE;
488     case SSL_AD_BAD_CERTIFICATE_HASH_VALUE:
489         return SSL3_AD_HANDSHAKE_FAILURE;
490     case SSL_AD_UNKNOWN_PSK_IDENTITY:
491         return TLS1_AD_UNKNOWN_PSK_IDENTITY;
492     case SSL_AD_INAPPROPRIATE_FALLBACK:
493         return TLS1_AD_INAPPROPRIATE_FALLBACK;
494     case SSL_AD_NO_APPLICATION_PROTOCOL:
495         return TLS1_AD_NO_APPLICATION_PROTOCOL;
496     case SSL_AD_CERTIFICATE_REQUIRED:
497         return SSL_AD_HANDSHAKE_FAILURE;
498     case TLS13_AD_MISSING_EXTENSION:
499         return SSL_AD_HANDSHAKE_FAILURE;
500     default:
501         return -1;
502     }
503 }
504