1 /* $OpenBSD: client.c,v 1.8 2019/03/21 17:52:26 bluhm Exp $ */ 2 /* 3 * Copyright (c) 2018-2019 Alexander Bluhm <bluhm@openbsd.org> 4 * 5 * Permission to use, copy, modify, and distribute this software for any 6 * purpose with or without fee is hereby granted, provided that the above 7 * copyright notice and this permission notice appear in all copies. 8 * 9 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 11 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 15 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 16 */ 17 18 #include <sys/types.h> 19 #include <sys/socket.h> 20 21 #include <err.h> 22 #include <netdb.h> 23 #include <stdio.h> 24 #include <string.h> 25 #include <unistd.h> 26 27 #include <openssl/err.h> 28 #include <openssl/ssl.h> 29 30 #include "util.h" 31 32 void __dead usage(void); 33 34 void __dead 35 usage(void) 36 { 37 fprintf(stderr, "usage: client [-Lsv] [-C CA] [-c crt -k key] " 38 "[-l ciphers] host port\n"); 39 exit(2); 40 } 41 42 int 43 main(int argc, char *argv[]) 44 { 45 const SSL_METHOD *method; 46 SSL_CTX *ctx; 47 SSL *ssl; 48 BIO *bio; 49 SSL_SESSION *session = NULL; 50 int ch, error, listciphers = 0, sessionreuse = 0, verify = 0; 51 char buf[256]; 52 char *ca = NULL, *crt = NULL, *key = NULL, *ciphers = NULL; 53 char *host_port, *host = "127.0.0.1", *port = "0"; 54 55 56 while ((ch = getopt(argc, argv, "C:c:k:Ll:sv")) != -1) { 57 switch (ch) { 58 case 'C': 59 ca = optarg; 60 break; 61 case 'c': 62 crt = optarg; 63 break; 64 case 'k': 65 key = optarg; 66 break; 67 case 'L': 68 listciphers = 1; 69 break; 70 case 'l': 71 ciphers = optarg; 72 break; 73 case 's': 74 /* multiple reueses are possible */ 75 sessionreuse++; 76 break; 77 case 'v': 78 verify = 1; 79 break; 80 default: 81 usage(); 82 } 83 } 84 argc -= optind; 85 argv += optind; 86 if (argc == 2) { 87 host = argv[0]; 88 port = argv[1]; 89 } else if (!listciphers) { 90 usage(); 91 } 92 if (asprintf(&host_port, strchr(host, ':') ? "[%s]:%s" : "%s:%s", 93 host, port) == -1) 94 err(1, "asprintf host port"); 95 if ((crt == NULL && key != NULL) || (crt != NULL && key == NULL)) 96 errx(1, "certificate and private key must be used together"); 97 98 SSL_library_init(); 99 SSL_load_error_strings(); 100 print_version(); 101 102 /* setup method and context */ 103 #if OPENSSL_VERSION_NUMBER >= 0x1010000f 104 method = TLS_client_method(); 105 if (method == NULL) 106 err_ssl(1, "TLS_client_method"); 107 #else 108 method = SSLv23_client_method(); 109 if (method == NULL) 110 err_ssl(1, "SSLv23_client_method"); 111 #endif 112 ctx = SSL_CTX_new(method); 113 if (ctx == NULL) 114 err_ssl(1, "SSL_CTX_new"); 115 116 /* load client certificate */ 117 if (crt != NULL) { 118 if (SSL_CTX_use_certificate_file(ctx, crt, 119 SSL_FILETYPE_PEM) <= 0) 120 err_ssl(1, "SSL_CTX_use_certificate_file"); 121 if (SSL_CTX_use_PrivateKey_file(ctx, key, 122 SSL_FILETYPE_PEM) <= 0) 123 err_ssl(1, "SSL_CTX_use_PrivateKey_file"); 124 if (SSL_CTX_check_private_key(ctx) <= 0) 125 err_ssl(1, "SSL_CTX_check_private_key"); 126 } 127 128 /* verify server certificate */ 129 if (ca != NULL) { 130 if (SSL_CTX_load_verify_locations(ctx, ca, NULL) <= 0) 131 err_ssl(1, "SSL_CTX_load_verify_locations"); 132 } 133 SSL_CTX_set_verify(ctx, verify ? SSL_VERIFY_PEER : SSL_VERIFY_NONE, 134 verify_callback); 135 136 if (sessionreuse) { 137 SSL_CTX_set_session_cache_mode(ctx, SSL_SESS_CACHE_CLIENT); 138 } 139 140 if (ciphers) { 141 if (SSL_CTX_set_cipher_list(ctx, ciphers) <= 0) 142 err_ssl(1, "SSL_CTX_set_cipher_list"); 143 } 144 145 if (listciphers) { 146 ssl = SSL_new(ctx); 147 if (ssl == NULL) 148 err_ssl(1, "SSL_new"); 149 print_ciphers(SSL_get_ciphers(ssl)); 150 return 0; 151 } 152 153 do { 154 /* setup bio for socket operations */ 155 bio = BIO_new_connect(host_port); 156 if (bio == NULL) 157 err_ssl(1, "BIO_new_connect"); 158 159 /* connect */ 160 if (BIO_do_connect(bio) <= 0) 161 err_ssl(1, "BIO_do_connect"); 162 printf("connect "); 163 print_sockname(bio); 164 printf("connect "); 165 print_peername(bio); 166 167 /* do ssl client handshake */ 168 ssl = SSL_new(ctx); 169 if (ssl == NULL) 170 err_ssl(1, "SSL_new"); 171 SSL_set_bio(ssl, bio, bio); 172 /* resuse session if possible */ 173 if (session != NULL) { 174 if (SSL_set_session(ssl, session) <= 0) 175 err_ssl(1, "SSL_set_session"); 176 } 177 if ((error = SSL_connect(ssl)) <= 0) 178 err_ssl(1, "SSL_connect %d", error); 179 printf("session %d: %s\n", sessionreuse, 180 SSL_session_reused(ssl) ? "reuse" : "new"); 181 if (fflush(stdout) != 0) 182 err(1, "fflush stdout"); 183 184 /* print session statistics */ 185 if (sessionreuse) { 186 session = SSL_get1_session(ssl); 187 if (session == NULL) 188 err_ssl(1, "SSL1_get_session"); 189 } else { 190 session = SSL_get_session(ssl); 191 if (session == NULL) 192 err_ssl(1, "SSL_get_session"); 193 } 194 if (SSL_SESSION_print_fp(stdout, session) <= 0) 195 err_ssl(1, "SSL_SESSION_print_fp"); 196 197 /* read server greeting and write client hello over TLS */ 198 if ((error = SSL_read(ssl, buf, 9)) <= 0) 199 err_ssl(1, "SSL_read %d", error); 200 if (error != 9) 201 errx(1, "read not 9 bytes greeting: %d", error); 202 buf[9] = '\0'; 203 printf("<<< %s", buf); 204 if (fflush(stdout) != 0) 205 err(1, "fflush stdout"); 206 strlcpy(buf, "hello\n", sizeof(buf)); 207 printf(">>> %s", buf); 208 if (fflush(stdout) != 0) 209 err(1, "fflush stdout"); 210 if ((error = SSL_write(ssl, buf, 6)) <= 0) 211 err_ssl(1, "SSL_write %d", error); 212 if (error != 6) 213 errx(1, "write not 6 bytes hello: %d", error); 214 215 /* shutdown connection */ 216 if ((error = SSL_shutdown(ssl)) < 0) 217 err_ssl(1, "SSL_shutdown unidirectional %d", error); 218 if (error <= 0) { 219 if ((error = SSL_shutdown(ssl)) <= 0) 220 err_ssl(1, "SSL_shutdown bidirectional %d", 221 error); 222 } 223 224 SSL_free(ssl); 225 } while (sessionreuse--); 226 227 SSL_CTX_free(ctx); 228 229 printf("success\n"); 230 231 return 0; 232 } 233