xref: /freebsd/crypto/openssl/ssl/s3_msg.c (revision e7be843b4a162e68651d3911f0357ed464915629)
1 /*
2  * Copyright 1995-2025 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/ssl_unwrap.h"
12 
ssl3_do_change_cipher_spec(SSL_CONNECTION * s)13 int ssl3_do_change_cipher_spec(SSL_CONNECTION *s)
14 {
15     int i;
16     SSL *ssl = SSL_CONNECTION_GET_SSL(s);
17 
18     if (s->server)
19         i = SSL3_CHANGE_CIPHER_SERVER_READ;
20     else
21         i = SSL3_CHANGE_CIPHER_CLIENT_READ;
22 
23     if (s->s3.tmp.key_block == NULL) {
24         if (s->session == NULL || s->session->master_key_length == 0) {
25             /* might happen if dtls1_read_bytes() calls this */
26             ERR_raise(ERR_LIB_SSL, SSL_R_CCS_RECEIVED_EARLY);
27             return 0;
28         }
29 
30         s->session->cipher = s->s3.tmp.new_cipher;
31         if (!ssl->method->ssl3_enc->setup_key_block(s)) {
32             /* SSLfatal() already called */
33             return 0;
34         }
35     }
36 
37     if (!ssl->method->ssl3_enc->change_cipher_state(s, i)) {
38         /* SSLfatal() already called */
39         return 0;
40     }
41 
42     return 1;
43 }
44 
ssl3_send_alert(SSL_CONNECTION * s,int level,int desc)45 int ssl3_send_alert(SSL_CONNECTION *s, int level, int desc)
46 {
47     SSL *ssl = SSL_CONNECTION_GET_SSL(s);
48 
49     /* Map tls/ssl alert value to correct one */
50     if (SSL_CONNECTION_TREAT_AS_TLS13(s))
51         desc = tls13_alert_code(desc);
52     else
53         desc = ssl->method->ssl3_enc->alert_value(desc);
54     if (s->version == SSL3_VERSION && desc == SSL_AD_PROTOCOL_VERSION)
55         desc = SSL_AD_HANDSHAKE_FAILURE; /* SSL 3.0 does not have
56                                           * protocol_version alerts */
57     if (desc < 0)
58         return -1;
59     if (s->shutdown & SSL_SENT_SHUTDOWN && desc != SSL_AD_CLOSE_NOTIFY)
60         return -1;
61     /* If a fatal one, remove from cache */
62     if ((level == SSL3_AL_FATAL) && (s->session != NULL))
63         SSL_CTX_remove_session(s->session_ctx, s->session);
64 
65     s->s3.alert_dispatch = SSL_ALERT_DISPATCH_PENDING;
66     s->s3.send_alert[0] = level;
67     s->s3.send_alert[1] = desc;
68     if (!RECORD_LAYER_write_pending(&s->rlayer)) {
69         /* data still being written out? */
70         return ssl->method->ssl_dispatch_alert(ssl);
71     }
72     /*
73      * else data is still being written out, we will get written some time in
74      * the future
75      */
76     return -1;
77 }
78 
ssl3_dispatch_alert(SSL * s)79 int ssl3_dispatch_alert(SSL *s)
80 {
81     int i, j;
82     void (*cb) (const SSL *ssl, int type, int val) = NULL;
83     SSL_CONNECTION *sc = SSL_CONNECTION_FROM_SSL(s);
84     OSSL_RECORD_TEMPLATE templ;
85 
86     if (sc == NULL)
87         return -1;
88 
89     if (sc->rlayer.wrlmethod == NULL) {
90         /* No write record layer so we can't sent and alert. We just ignore it */
91         sc->s3.alert_dispatch = SSL_ALERT_DISPATCH_NONE;
92         return 1;
93     }
94 
95     templ.type = SSL3_RT_ALERT;
96     templ.version = (sc->version == TLS1_3_VERSION) ? TLS1_2_VERSION
97                                                     : sc->version;
98     if (SSL_get_state(s) == TLS_ST_CW_CLNT_HELLO
99             && !sc->renegotiate
100             && TLS1_get_version(s) > TLS1_VERSION
101             && sc->hello_retry_request == SSL_HRR_NONE) {
102         templ.version = TLS1_VERSION;
103     }
104     templ.buf = &sc->s3.send_alert[0];
105     templ.buflen = 2;
106 
107     if (RECORD_LAYER_write_pending(&sc->rlayer)) {
108         if (sc->s3.alert_dispatch != SSL_ALERT_DISPATCH_RETRY) {
109             /*
110              * We have a write pending but it wasn't from a previous call to
111              * this function! Can we ever get here? Maybe via API misuse??
112              * Give up.
113              */
114             sc->s3.alert_dispatch = SSL_ALERT_DISPATCH_NONE;
115             return -1;
116         }
117         /* Retry what we've already got pending */
118         i = HANDLE_RLAYER_WRITE_RETURN(sc,
119                 sc->rlayer.wrlmethod->retry_write_records(sc->rlayer.wrl));
120         if (i <= 0) {
121             /* Could be NBIO. Keep alert_dispatch as SSL_ALERT_DISPATCH_RETRY */
122             return -1;
123         }
124         sc->rlayer.wpend_tot = 0;
125         sc->s3.alert_dispatch = SSL_ALERT_DISPATCH_NONE;
126         return 1;
127     }
128 
129     i = HANDLE_RLAYER_WRITE_RETURN(sc,
130             sc->rlayer.wrlmethod->write_records(sc->rlayer.wrl, &templ, 1));
131 
132     if (i <= 0) {
133         sc->s3.alert_dispatch = SSL_ALERT_DISPATCH_RETRY;
134         sc->rlayer.wpend_tot = templ.buflen;
135         sc->rlayer.wpend_type = templ.type;
136         sc->rlayer.wpend_buf = templ.buf;
137     } else {
138         /*
139          * Alert sent to BIO - now flush. If the message does not get sent due
140          * to non-blocking IO, we will not worry too much.
141          */
142         (void)BIO_flush(sc->wbio);
143         sc->s3.alert_dispatch = SSL_ALERT_DISPATCH_NONE;
144 
145         if (sc->msg_callback)
146             sc->msg_callback(1, sc->version, SSL3_RT_ALERT, sc->s3.send_alert,
147                              2, s, sc->msg_callback_arg);
148 
149         if (sc->info_callback != NULL)
150             cb = sc->info_callback;
151         else if (s->ctx->info_callback != NULL)
152             cb = s->ctx->info_callback;
153 
154         if (cb != NULL) {
155             j = (sc->s3.send_alert[0] << 8) | sc->s3.send_alert[1];
156             cb(s, SSL_CB_WRITE_ALERT, j);
157         }
158     }
159     return i;
160 }
161