2 * Copyright 2016 The OpenSSL Project Authors. All Rights Reserved.
4 * Licensed under the OpenSSL license (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
13 #include <openssl/dtls1.h>
14 #include <openssl/ssl.h>
15 #include <openssl/err.h>
17 #include "ssltestlib.h"
19 /* for SSL_READ_ETM() */
20 #include "../ssl/ssl_locl.h"
24 static unsigned int clnt_psk_callback(SSL *ssl, const char *hint,
25 char *ident, unsigned int max_ident_len,
27 unsigned int max_psk_len)
29 BIO_snprintf(ident, max_ident_len, "psk");
33 memset(psk, 0x5a, max_psk_len);
38 static unsigned int srvr_psk_callback(SSL *ssl, const char *identity,
40 unsigned int max_psk_len)
44 memset(psk, 0x5a, max_psk_len);
48 static int mtu_test(SSL_CTX *ctx, const char *cs, int no_etm)
50 SSL *srvr_ssl = NULL, *clnt_ssl = NULL;
55 unsigned char buf[600];
58 memset(buf, 0x5a, sizeof(buf));
60 if (create_ssl_objects(ctx, ctx, &srvr_ssl, &clnt_ssl, NULL, NULL) != 1)
64 SSL_set_options(srvr_ssl, SSL_OP_NO_ENCRYPT_THEN_MAC);
66 if (SSL_set_cipher_list(srvr_ssl, cs) != 1 ||
67 SSL_set_cipher_list(clnt_ssl, cs) != 1) {
68 ERR_print_errors_fp(stdout);
71 sc_bio = SSL_get_rbio(srvr_ssl);
73 if (create_ssl_connection(clnt_ssl, srvr_ssl, SSL_ERROR_NONE) != 1)
77 printf("Channel established\n");
79 /* For record MTU values between 500 and 539, call DTLS_get_data_mtu()
80 * to query the payload MTU which will fit. */
81 for (i = 0; i < 30; i++) {
82 SSL_set_mtu(clnt_ssl, 500 + i);
83 mtus[i] = DTLS_get_data_mtu(clnt_ssl);
85 printf("%s%s payload MTU for record mtu %d = %"OSSLzu"\n",
86 cs, no_etm ? "-noEtM":"", 500 + i, mtus[i]);
89 "payload MTU failed with record MTU %d for %s\n",
95 /* Now get out of the way */
96 SSL_set_mtu(clnt_ssl, 1000);
98 /* Now for all values in the range of payload MTUs, send
99 * a payload of that size and see what actual record size
101 for (s = mtus[0]; s <= mtus[29]; s++) {
103 if (SSL_write(clnt_ssl, buf, s) != (int)s) {
104 ERR_print_errors_fp(stdout);
107 reclen = BIO_read(sc_bio, buf, sizeof(buf));
109 printf("record %"OSSLzu" for payload %"OSSLzu"\n", reclen, s);
111 for (i = 0; i < 30; i++) {
112 /* DTLS_get_data_mtu() with record MTU 500+i returned mtus[i] ... */
114 if (s <= mtus[i] && reclen > (size_t)(500 + i)) {
115 /* We sent a packet smaller than or equal to mtus[j] and
116 * that made a record *larger* than the record MTU 500+j! */
118 "%s: Payload MTU %"OSSLzu" reported for record MTU %d\n"
119 "but sending a payload of %"OSSLzu" made a record of %"OSSLzu"(too large)\n",
120 cs, mtus[i], 500 + i, s, reclen);
123 if (s > mtus[i] && reclen <= (size_t)(500 + i)) {
124 /* We sent a *larger* packet than mtus[i] and that *still*
125 * fits within the record MTU 500+i, so DTLS_get_data_mtu()
126 * was overly pessimistic. */
128 "%s: Payload MTU %"OSSLzu" reported for record MTU %d\n"
129 "but sending a payload of %"OSSLzu" made a record of %"OSSLzu" (too small)\n",
130 cs, mtus[i], 500 + i, s, reclen);
136 if (SSL_READ_ETM(clnt_ssl))
146 SSL_CTX *ctx = SSL_CTX_new(DTLS_method());
147 STACK_OF(SSL_CIPHER) *ciphers;
150 SSL_CTX_set_psk_server_callback(ctx, srvr_psk_callback);
151 SSL_CTX_set_psk_client_callback(ctx, clnt_psk_callback);
152 SSL_CTX_set_security_level(ctx, 0);
154 /* We only care about iterating over each enc/mac; we don't
155 * want to repeat the test for each auth/kx variant.
156 * So keep life simple and only do (non-DH) PSK. */
157 if (!SSL_CTX_set_cipher_list(ctx, "PSK")) {
158 fprintf(stderr, "Failed to set PSK cipher list\n");
162 ciphers = SSL_CTX_get_ciphers(ctx);
163 for (i = 0; i < sk_SSL_CIPHER_num(ciphers); i++) {
164 const SSL_CIPHER *cipher = sk_SSL_CIPHER_value(ciphers, i);
165 const char *cipher_name = SSL_CIPHER_get_name(cipher);
167 /* As noted above, only one test for each enc/mac variant. */
168 if (strncmp(cipher_name, "PSK-", 4))
171 rv = mtu_test(ctx, cipher_name, 0);
175 printf("DTLS MTU test OK for %s\n", cipher_name);
179 /* mtu_test() returns 2 if it used Encrypt-then-MAC */
180 rv = mtu_test(ctx, cipher_name, 1);
184 printf("DTLS MTU test OK for %s without Encrypt-then-MAC\n", cipher_name);