xref: /freebsd/crypto/openssl/demos/bio/server-cmod.c (revision 88b8b7f0c4e9948667a2279e78e975a784049cba)
1 /*
2  * Copyright 2015-2025 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 /*
11  * A minimal TLS server it ses SSL_CTX_config and a configuration file to
12  * set most server parameters.
13  */
14 
15 #include <stdio.h>
16 #include <signal.h>
17 #include <stdlib.h>
18 #include <openssl/err.h>
19 #include <openssl/ssl.h>
20 #include <openssl/conf.h>
21 
main(int argc,char * argv[])22 int main(int argc, char *argv[])
23 {
24     unsigned char buf[512];
25     char *port = "*:4433";
26     BIO *in = NULL;
27     BIO *ssl_bio = NULL;
28     BIO *tmp;
29     SSL_CTX *ctx;
30     int ret = EXIT_FAILURE, i;
31 
32     ctx = SSL_CTX_new(TLS_server_method());
33 
34     if (CONF_modules_load_file("cmod.cnf", "testapp", 0) <= 0) {
35         fprintf(stderr, "Error processing config file\n");
36         goto err;
37     }
38 
39     if (SSL_CTX_config(ctx, "server") == 0) {
40         fprintf(stderr, "Error configuring server.\n");
41         goto err;
42     }
43 
44     /* Setup server side SSL bio */
45     ssl_bio = BIO_new_ssl(ctx, 0);
46 
47     if ((in = BIO_new_accept(port)) == NULL)
48         goto err;
49 
50     /*
51      * This means that when a new connection is accepted on 'in', The ssl_bio
52      * will be 'duplicated' and have the new socket BIO push into it.
53      * Basically it means the SSL BIO will be automatically setup
54      */
55     BIO_set_accept_bios(in, ssl_bio);
56     ssl_bio = NULL;
57 
58  again:
59     /*
60      * The first call will setup the accept socket, and the second will get a
61      * socket.  In this loop, the first actual accept will occur in the
62      * BIO_read() function.
63      */
64 
65     if (BIO_do_accept(in) <= 0)
66         goto err;
67 
68     for (;;) {
69         i = BIO_read(in, buf, sizeof(buf));
70         if (i == 0) {
71             /*
72              * If we have finished, remove the underlying BIO stack so the
73              * next time we call any function for this BIO, it will attempt
74              * to do an accept
75              */
76             printf("Done\n");
77             tmp = BIO_pop(in);
78             BIO_free_all(tmp);
79             goto again;
80         }
81         if (i < 0) {
82             if (BIO_should_retry(in))
83                 continue;
84             goto err;
85         }
86         fwrite(buf, 1, i, stdout);
87         fflush(stdout);
88     }
89 
90     ret = EXIT_SUCCESS;
91  err:
92     if (ret != EXIT_SUCCESS)
93         ERR_print_errors_fp(stderr);
94     BIO_free(in);
95     BIO_free_all(ssl_bio);
96     return ret;
97 }
98