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 30 static void interrupt(int sig) 31 { 32 done = 1; 33 } 34 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 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