1 /*
2 * Copyright 1998-2025 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 program to serve an SSL connection.
12 * It uses blocking.
13 * saccept host:port
14 * host is the interface IP to use. If any interface, use *:port
15 * The default it *:4433
16 *
17 * cc -I../../include saccept.c -L../.. -lssl -lcrypto -ldl
18 */
19
20 #include <stdio.h>
21 #include <signal.h>
22 #include <stdlib.h>
23 #include <openssl/err.h>
24 #include <openssl/ssl.h>
25
26 #define CERT_FILE "server.pem"
27
28 static volatile int done = 0;
29
interrupt(int sig)30 static void interrupt(int sig)
31 {
32 done = 1;
33 }
34
sigsetup(void)35 static void sigsetup(void)
36 {
37 #if defined(OPENSSL_SYS_WINDOWS)
38 signal(SIGINT, interrupt);
39 #else
40 struct sigaction sa;
41
42 /*
43 * Catch at most once, and don't restart the accept system call.
44 */
45 sa.sa_flags = SA_RESETHAND;
46 sa.sa_handler = interrupt;
47 sigemptyset(&sa.sa_mask);
48 sigaction(SIGINT, &sa, NULL);
49 #endif
50 }
51
main(int argc,char * argv[])52 int main(int argc, char *argv[])
53 {
54 char *port = NULL;
55 BIO *in = NULL;
56 BIO *ssl_bio = NULL;
57 BIO *tmp;
58 SSL_CTX *ctx;
59 char buf[512];
60 int ret = EXIT_FAILURE, i;
61
62 if (argc <= 1)
63 port = "*:4433";
64 else
65 port = argv[1];
66
67 ctx = SSL_CTX_new(TLS_server_method());
68 if (!SSL_CTX_use_certificate_chain_file(ctx, CERT_FILE))
69 goto err;
70 if (!SSL_CTX_use_PrivateKey_file(ctx, CERT_FILE, SSL_FILETYPE_PEM))
71 goto err;
72 if (!SSL_CTX_check_private_key(ctx))
73 goto err;
74
75 /* Setup server side SSL bio */
76 ssl_bio = BIO_new_ssl(ctx, 0);
77
78 if ((in = BIO_new_accept(port)) == NULL)
79 goto err;
80
81 /*
82 * This means that when a new connection is accepted on 'in', The ssl_bio
83 * will be 'duplicated' and have the new socket BIO push into it.
84 * Basically it means the SSL BIO will be automatically setup
85 */
86 BIO_set_accept_bios(in, ssl_bio);
87 ssl_bio = NULL;
88
89 /* Arrange to leave server loop on interrupt */
90 sigsetup();
91
92 again:
93 /*
94 * The first call will setup the accept socket, and the second will get a
95 * socket. In this loop, the first actual accept will occur in the
96 * BIO_read() function.
97 */
98
99 if (BIO_do_accept(in) <= 0)
100 goto err;
101
102 while (!done) {
103 i = BIO_read(in, buf, 512);
104 if (i == 0) {
105 /*
106 * If we have finished, remove the underlying BIO stack so the
107 * next time we call any function for this BIO, it will attempt
108 * to do an accept
109 */
110 printf("Done\n");
111 tmp = BIO_pop(in);
112 BIO_free_all(tmp);
113 goto again;
114 }
115 if (i < 0)
116 goto err;
117 fwrite(buf, 1, i, stdout);
118 fflush(stdout);
119 }
120
121 ret = EXIT_SUCCESS;
122 err:
123 if (ret != EXIT_SUCCESS)
124 ERR_print_errors_fp(stderr);
125 BIO_free(in);
126 BIO_free_all(ssl_bio);
127 return ret;
128 }
129