tests/unit_tests/openvpn/test_crypto.c

   1 /*
   2  *  OpenVPN -- An application to securely tunnel IP networks
   3  *             over a single UDP port, with support for SSL/TLS-based
   4  *             session authentication and key exchange,
   5  *             packet encryption, packet authentication, and
   6  *             packet compression.
   7  *
   8  *  Copyright (C) 2016-2021 Fox Crypto B.V. <openvpn@foxcrypto.com>
   9  *
  10  *  This program is free software; you can redistribute it and/or modify
  11  *  it under the terms of the GNU General Public License version 2
  12  *  as published by the Free Software Foundation.
  13  *
  14  *  This program is distributed in the hope that it will be useful,
  15  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  *  GNU General Public License for more details.
  18  *
  19  *  You should have received a copy of the GNU General Public License along
  20  *  with this program; if not, write to the Free Software Foundation, Inc.,
  21  *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  22  */
  23
  24 #ifdef HAVE_CONFIG_H
  25 #include "config.h"
  26 #elif defined(_MSC_VER)
  27 #include "config-msvc.h"
  28 #endif
  29
  30 #include "syshead.h"
  31
  32 #include <stdio.h>
  33 #include <stdlib.h>
  34 #include <stdarg.h>
  35 #include <string.h>
  36 #include <setjmp.h>
  37 #include <cmocka.h>
  38
  39 #include "crypto.h"
  40 #include "options.h"
  41 #include "ssl_backend.h"
  42
  43 #include "mock_msg.h"
  44
  45 static const char testtext[] = "Dummy text to test PEM encoding";
  46
  47 static void
  48 crypto_pem_encode_decode_loopback(void **state)
  49 {
  50     struct gc_arena gc = gc_new();
  51     struct buffer src_buf;
  52     buf_set_read(&src_buf, (void *)testtext, sizeof(testtext));
  53
  54     uint8_t dec[sizeof(testtext)];
  55     struct buffer dec_buf;
  56     buf_set_write(&dec_buf, dec, sizeof(dec));
  57
  58     struct buffer pem_buf;
  59
  60     assert_true(crypto_pem_encode("TESTKEYNAME", &pem_buf, &src_buf, &gc));
  61     assert_true(BLEN(&src_buf) < BLEN(&pem_buf));
  62
  63     /* Wrong key name */
  64     assert_false(crypto_pem_decode("WRONGNAME", &dec_buf, &pem_buf));
  65
  66     assert_true(crypto_pem_decode("TESTKEYNAME", &dec_buf, &pem_buf));
  67     assert_int_equal(BLEN(&src_buf), BLEN(&dec_buf));
  68     assert_memory_equal(BPTR(&src_buf), BPTR(&dec_buf), BLEN(&src_buf));
  69
  70     gc_free(&gc);
  71 }
  72
  73 static void
  74 test_translate_cipher(const char *ciphername, const char *openvpn_name)
  75 {
  76     bool cipher = cipher_valid(ciphername);
  77
  78     /* Empty cipher is fine */
  79     if (!cipher)
  80     {
  81         return;
  82     }
  83
  84     const char *kt_name = cipher_kt_name(ciphername);
  85
  86     assert_string_equal(kt_name, openvpn_name);
  87 }
  88
  89 static void
  90 test_cipher_names(const char *ciphername, const char *openvpn_name)
  91 {
  92     struct gc_arena gc = gc_new();
  93     /* Go through some variants, if the cipher library accepts these, they
  94      * should be normalised to the openvpn name */
  95     char *upper = string_alloc(ciphername, &gc);
  96     char *lower = string_alloc(ciphername, &gc);
  97     char *random_case = string_alloc(ciphername, &gc);
  98
  99     for (int i = 0; i < strlen(ciphername); i++)
 100     {
 101         upper[i] = toupper(ciphername[i]);
 102         lower[i] = tolower(ciphername[i]);
 103         if (rand() & 0x1)
 104         {
 105             random_case[i] = upper[i];
 106         }
 107         else
 108         {
 109             random_case[i] = lower[i];
 110         }
 111     }
 112
 113     if (!openvpn_name)
 114     {
 115         openvpn_name = upper;
 116     }
 117
 118     test_translate_cipher(upper, openvpn_name);
 119     test_translate_cipher(lower, openvpn_name);
 120     test_translate_cipher(random_case, openvpn_name);
 121     test_translate_cipher(ciphername, openvpn_name);
 122
 123
 124     gc_free(&gc);
 125 }
 126
 127 static void
 128 crypto_translate_cipher_names(void **state)
 129 {
 130     /* Test that a number of ciphers to see that they turn out correctly */
 131     test_cipher_names("BF-CBC", NULL);
 132     test_cipher_names("BLOWFISH-CBC", "BF-CBC");
 133     test_cipher_names("Chacha20-Poly1305", NULL);
 134     test_cipher_names("AES-128-GCM", NULL);
 135     test_cipher_names("AES-128-CBC", NULL);
 136     test_cipher_names("CAMELLIA-128-CFB128", "CAMELLIA-128-CFB");
 137     test_cipher_names("id-aes256-GCM", "AES-256-GCM");
 138 }
 139
 140
 141 static uint8_t good_prf[32] = {0xd9, 0x8c, 0x85, 0x18, 0xc8, 0x5e, 0x94, 0x69,
 142                                0x27, 0x91, 0x6a, 0xcf, 0xc2, 0xd5, 0x92, 0xfb,
 143                                0xb1, 0x56, 0x7e, 0x4b, 0x4b, 0x14, 0x59, 0xe6,
 144                                0xa9, 0x04, 0xac, 0x2d, 0xda, 0xb7, 0x2d, 0x67};
 145
 146 static const char* ipsumlorem = "Lorem ipsum dolor sit amet, consectetur "
 147                                 "adipisici elit, sed eiusmod tempor incidunt "
 148                                 "ut labore et dolore magna aliqua.";
 149
 150 static void
 151 crypto_test_tls_prf(void **state)
 152 {
 153     const char *seedstr = "Quis aute iure reprehenderit in voluptate "
 154                           "velit esse cillum dolore";
 155     const unsigned char *seed = (const unsigned char *)seedstr;
 156     const size_t seed_len = strlen(seedstr);
 157
 158
 159     const unsigned char *secret = (const unsigned char *) ipsumlorem;
 160     size_t secret_len = strlen((const char *)secret);
 161
 162
 163     uint8_t out[32];
 164     ssl_tls1_PRF(seed, seed_len, secret, secret_len, out, sizeof(out));
 165
 166     assert_memory_equal(good_prf, out, sizeof(out));
 167 }
 168
 169 static uint8_t testkey[20] = {0x0b, 0x00};
 170 static uint8_t goodhash[20] = {0x58, 0xea, 0x5a, 0xf0, 0x42, 0x94, 0xe9, 0x17,
 171                                0xed, 0x84, 0xb9, 0xf0, 0x83, 0x30, 0x23, 0xae,
 172                                0x8b, 0xa7, 0x7e, 0xb8};
 173
 174 static void
 175 crypto_test_hmac(void **state)
 176 {
 177     hmac_ctx_t *hmac = hmac_ctx_new();
 178
 179     assert_int_equal(md_kt_size("SHA1"), 20);
 180
 181     uint8_t key[20];
 182     memcpy(key, testkey, sizeof(key));
 183
 184     hmac_ctx_init(hmac, key, "SHA1");
 185     hmac_ctx_update(hmac, (const uint8_t *)ipsumlorem, (int) strlen(ipsumlorem));
 186     hmac_ctx_update(hmac, (const uint8_t *)ipsumlorem, (int) strlen(ipsumlorem));
 187
 188     uint8_t hash[20];
 189     hmac_ctx_final(hmac, hash);
 190
 191     assert_memory_equal(hash, goodhash, sizeof(hash));
 192     memset(hash, 0x00, sizeof(hash));
 193
 194     /* try again */
 195     hmac_ctx_reset(hmac);
 196     hmac_ctx_update(hmac, (const uint8_t *)ipsumlorem, (int) strlen(ipsumlorem));
 197     hmac_ctx_update(hmac, (const uint8_t *)ipsumlorem, (int) strlen(ipsumlorem));
 198     hmac_ctx_final(hmac, hash);
 199
 200     assert_memory_equal(hash, goodhash, sizeof(hash));
 201
 202     /* Fill our key with random data to ensure it is not used by hmac anymore */
 203     memset(key, 0x55, sizeof(key));
 204
 205     hmac_ctx_reset(hmac);
 206     hmac_ctx_update(hmac, (const uint8_t *)ipsumlorem, (int) strlen(ipsumlorem));
 207     hmac_ctx_update(hmac, (const uint8_t *)ipsumlorem, (int) strlen(ipsumlorem));
 208     hmac_ctx_final(hmac, hash);
 209
 210     assert_memory_equal(hash, goodhash, sizeof(hash));
 211     hmac_ctx_cleanup(hmac);
 212     hmac_ctx_free(hmac);
 213 }
 214
 215 void
 216 test_des_encrypt(void **state)
 217 {
 218     /* We have a small des encrypt method that is only for NTLMv1. This unit
 219      * test ensures that it is not accidentally broken */
 220
 221     const unsigned char des_key[DES_KEY_LENGTH] = {0x42, 0x23};
 222
 223     const char *src = "MoinWelt";
 224
 225     /* cipher_des_encrypt_ecb wants a non const */
 226     unsigned char *src2 = (unsigned char *) strdup(src);
 227
 228     unsigned char dst[DES_KEY_LENGTH];
 229     cipher_des_encrypt_ecb(des_key, src2, dst);
 230
 231     const unsigned char dst_good[DES_KEY_LENGTH] = {0xd3, 0x8f, 0x61, 0xf7, 0xbe, 0x27, 0xb6, 0xa2};
 232
 233     assert_memory_equal(dst, dst_good, DES_KEY_LENGTH);
 234
 235     free(src2);
 236 }
 237
 238 /* This test is in test_crypto as it calls into the functions that calculate
 239  * the crypto overhead */
 240 static void
 241 test_occ_mtu_calculation(void **state)
 242 {
 243     struct gc_arena gc = gc_new();
 244
 245     struct frame f = { 0 };
 246     struct options o = { 0 };
 247     size_t linkmtu;
 248
 249     /* common defaults */
 250     o.ce.tun_mtu = 1400;
 251     o.replay = true;
 252     o.ce.proto = PROTO_UDP;
 253
 254     /* No crypto at all */
 255     o.ciphername = "none";
 256     o.authname = "none";
 257     linkmtu = calc_options_string_link_mtu(&o, &f);
 258     assert_int_equal(linkmtu, 1400);
 259
 260     /* Static key OCC examples */
 261     o.shared_secret_file = "not null";
 262
 263     /* secret, auth none, cipher none */
 264     o.ciphername = "none";
 265     o.authname = "none";
 266     linkmtu = calc_options_string_link_mtu(&o, &f);
 267     assert_int_equal(linkmtu, 1408);
 268
 269     /* secret, cipher AES-128-CBC, auth none */
 270     o.ciphername = "AES-128-CBC";
 271     o.authname = "none";
 272     linkmtu = calc_options_string_link_mtu(&o, &f);
 273     assert_int_equal(linkmtu, 1440);
 274
 275     /* secret, cipher none, auth SHA256 */
 276     o.ciphername = "none";
 277     o.authname = "SHA256";
 278     linkmtu = calc_options_string_link_mtu(&o, &f);
 279     assert_int_equal(linkmtu, 1440);
 280
 281     /* secret, cipher BF-CBC, auth SHA1 */
 282     o.ciphername = "BF-CBC";
 283     o.authname = "SHA1";
 284     linkmtu = calc_options_string_link_mtu(&o, &f);
 285     assert_int_equal(linkmtu, 1444);
 286
 287     /* secret, cipher BF-CBC, auth SHA1, tcp-client */
 288     o.ce.proto = PROTO_TCP_CLIENT;
 289     linkmtu = calc_options_string_link_mtu(&o, &f);
 290     assert_int_equal(linkmtu, 1446);
 291
 292     o.ce.proto = PROTO_UDP;
 293
 294 #if defined(USE_COMP)
 295     o.comp.alg = COMP_ALG_LZO;
 296
 297     /* secret, comp-lzo yes, cipher BF-CBC, auth SHA1 */
 298     linkmtu = calc_options_string_link_mtu(&o, &f);
 299     assert_int_equal(linkmtu, 1445);
 300
 301     /* secret, comp-lzo yes, cipher BF-CBC, auth SHA1, fragment 1200 */
 302     o.ce.fragment = 1200;
 303     linkmtu = calc_options_string_link_mtu(&o, &f);
 304     assert_int_equal(linkmtu, 1449);
 305
 306     o.comp.alg = COMP_ALG_UNDEF;
 307     o.ce.fragment = 0;
 308 #endif
 309
 310     /* TLS mode */
 311     o.shared_secret_file = NULL;
 312     o.tls_client = true;
 313     o.pull = true;
 314
 315     /* tls client, cipher AES-128-CBC, auth SHA1, tls-auth */
 316     o.authname = "SHA1";
 317     o.ciphername = "AES-128-CBC";
 318     o.tls_auth_file = "dummy";
 319
 320     linkmtu = calc_options_string_link_mtu(&o, &f);
 321     assert_int_equal(linkmtu, 1457);
 322
 323     /* tls client, cipher AES-128-CBC, auth SHA1 */
 324     o.tls_auth_file = NULL;
 325
 326     linkmtu = calc_options_string_link_mtu(&o, &f);
 327     assert_int_equal(linkmtu, 1457);
 328
 329     /* tls client, cipher none, auth none */
 330     o.authname = "none";
 331     o.ciphername = "none";
 332
 333     linkmtu = calc_options_string_link_mtu(&o, &f);
 334     assert_int_equal(linkmtu, 1405);
 335
 336     /* tls client, auth none, cipher none, no-replay */
 337     o.replay = false;
 338
 339     linkmtu = calc_options_string_link_mtu(&o, &f);
 340     assert_int_equal(linkmtu, 1401);
 341
 342
 343     o.replay = true;
 344
 345     /* tls client, auth SHA1, cipher AES-256-GCM */
 346     o.authname = "SHA1";
 347     o.ciphername = "AES-256-GCM";
 348     linkmtu = calc_options_string_link_mtu(&o, &f);
 349     assert_int_equal(linkmtu, 1449);
 350
 351
 352 #if defined(USE_COMP)
 353     o.comp.alg = COMP_ALG_LZO;
 354
 355     /* tls client, auth SHA1, cipher AES-256-GCM, fragment, comp-lzo yes */
 356     o.ce.fragment = 1200;
 357     linkmtu = calc_options_string_link_mtu(&o, &f);
 358     assert_int_equal(linkmtu, 1454);
 359
 360     /* tls client, auth SHA1, cipher AES-256-GCM, fragment, comp-lzo yes, socks */
 361     o.ce.socks_proxy_server = "socks.example.com";
 362     linkmtu = calc_options_string_link_mtu(&o, &f);
 363     assert_int_equal(linkmtu, 1464);
 364 #endif
 365
 366     gc_free(&gc);
 367 }
 368
 369 int
 370 main(void)
 371 {
 372     const struct CMUnitTest tests[] = {
 373         cmocka_unit_test(crypto_pem_encode_decode_loopback),
 374         cmocka_unit_test(crypto_translate_cipher_names),
 375         cmocka_unit_test(crypto_test_tls_prf),
 376         cmocka_unit_test(crypto_test_hmac),
 377         cmocka_unit_test(test_des_encrypt),
 378         cmocka_unit_test(test_occ_mtu_calculation)
 379     };
 380
 381 #if defined(ENABLE_CRYPTO_OPENSSL)
 382     OpenSSL_add_all_algorithms();
 383 #endif
 384
 385     int ret = cmocka_run_group_tests_name("crypto tests", tests, NULL, NULL);
 386
 387 #if defined(ENABLE_CRYPTO_OPENSSL)
 388     EVP_cleanup();
 389 #endif
 390
 391     return ret;
 392 }