1 /* test/heartbeat_test.c */
2 /*-
3 * Unit test for TLS heartbeats.
4 *
5 * Acts as a regression test against the Heartbleed bug (CVE-2014-0160).
6 *
7 * Author: Mike Bland (mbland@acm.org, http://mike-bland.com/)
8 * Date: 2014-04-12
9 * License: Creative Commons Attribution 4.0 International (CC By 4.0)
10 * http://creativecommons.org/licenses/by/4.0/deed.en_US
11 *
12 * OUTPUT
13 * ------
14 * The program returns zero on success. It will print a message with a count
15 * of the number of failed tests and return nonzero if any tests fail.
16 *
17 * It will print the contents of the request and response buffers for each
18 * failing test. In a "fixed" version, all the tests should pass and there
19 * should be no output.
20 *
21 * In a "bleeding" version, you'll see:
22 *
23 * test_dtls1_heartbleed failed:
24 * expected payload len: 0
25 * received: 1024
26 * sent 26 characters
27 * "HEARTBLEED "
28 * received 1024 characters
29 * "HEARTBLEED \xde\xad\xbe\xef..."
30 * ** test_dtls1_heartbleed failed **
31 *
32 * The contents of the returned buffer in the failing test will depend on the
33 * contents of memory on your machine.
34 *
35 * MORE INFORMATION
36 * ----------------
37 * http://mike-bland.com/2014/04/12/heartbleed.html
38 * http://mike-bland.com/tags/heartbleed.html
39 */
40
41 #define OPENSSL_UNIT_TEST
42
43 #include "../test/testutil.h"
44
45 #include "../ssl/ssl_locl.h"
46 #include <ctype.h>
47 #include <stdio.h>
48 #include <stdlib.h>
49 #include <string.h>
50
51 #if !defined(OPENSSL_NO_HEARTBEATS) && !defined(OPENSSL_NO_UNIT_TEST)
52
53 /* As per https://tools.ietf.org/html/rfc6520#section-4 */
54 # define MIN_PADDING_SIZE 16
55
56 /* Maximum number of payload characters to print as test output */
57 # define MAX_PRINTABLE_CHARACTERS 1024
58
59 typedef struct heartbeat_test_fixture {
60 SSL_CTX *ctx;
61 SSL *s;
62 const char *test_case_name;
63 int (*process_heartbeat) (SSL *s);
64 unsigned char *payload;
65 int sent_payload_len;
66 int expected_return_value;
67 int return_payload_offset;
68 int expected_payload_len;
69 const char *expected_return_payload;
70 } HEARTBEAT_TEST_FIXTURE;
71
set_up(const char * const test_case_name,const SSL_METHOD * meth)72 static HEARTBEAT_TEST_FIXTURE set_up(const char *const test_case_name,
73 const SSL_METHOD *meth)
74 {
75 HEARTBEAT_TEST_FIXTURE fixture;
76 int setup_ok = 1;
77 memset(&fixture, 0, sizeof(fixture));
78 fixture.test_case_name = test_case_name;
79
80 fixture.ctx = SSL_CTX_new(meth);
81 if (!fixture.ctx) {
82 fprintf(stderr, "Failed to allocate SSL_CTX for test: %s\n",
83 test_case_name);
84 setup_ok = 0;
85 goto fail;
86 }
87
88 fixture.s = SSL_new(fixture.ctx);
89 if (!fixture.s) {
90 fprintf(stderr, "Failed to allocate SSL for test: %s\n",
91 test_case_name);
92 setup_ok = 0;
93 goto fail;
94 }
95
96 if (!ssl_init_wbio_buffer(fixture.s, 1)) {
97 fprintf(stderr, "Failed to set up wbio buffer for test: %s\n",
98 test_case_name);
99 setup_ok = 0;
100 goto fail;
101 }
102
103 if (!ssl3_setup_buffers(fixture.s)) {
104 fprintf(stderr, "Failed to setup buffers for test: %s\n",
105 test_case_name);
106 setup_ok = 0;
107 goto fail;
108 }
109
110 /*
111 * Clear the memory for the return buffer, since this isn't automatically
112 * zeroed in opt mode and will cause spurious test failures that will
113 * change with each execution.
114 */
115 memset(fixture.s->s3->wbuf.buf, 0, fixture.s->s3->wbuf.len);
116
117 fail:
118 if (!setup_ok) {
119 ERR_print_errors_fp(stderr);
120 exit(EXIT_FAILURE);
121 }
122 return fixture;
123 }
124
set_up_dtls(const char * const test_case_name)125 static HEARTBEAT_TEST_FIXTURE set_up_dtls(const char *const test_case_name)
126 {
127 HEARTBEAT_TEST_FIXTURE fixture = set_up(test_case_name,
128 DTLSv1_server_method());
129 fixture.process_heartbeat = dtls1_process_heartbeat;
130
131 /*
132 * As per dtls1_get_record(), skipping the following from the beginning
133 * of the returned heartbeat message: type-1 byte; version-2 bytes;
134 * sequence number-8 bytes; length-2 bytes And then skipping the 1-byte
135 * type encoded by process_heartbeat for a total of 14 bytes, at which
136 * point we can grab the length and the payload we seek.
137 */
138 fixture.return_payload_offset = 14;
139 return fixture;
140 }
141
142 /* Needed by ssl3_write_bytes() */
dummy_handshake(SSL * s)143 static int dummy_handshake(SSL *s)
144 {
145 return 1;
146 }
147
set_up_tls(const char * const test_case_name)148 static HEARTBEAT_TEST_FIXTURE set_up_tls(const char *const test_case_name)
149 {
150 HEARTBEAT_TEST_FIXTURE fixture = set_up(test_case_name,
151 TLSv1_server_method());
152 fixture.process_heartbeat = tls1_process_heartbeat;
153 fixture.s->handshake_func = dummy_handshake;
154
155 /*
156 * As per do_ssl3_write(), skipping the following from the beginning of
157 * the returned heartbeat message: type-1 byte; version-2 bytes; length-2
158 * bytes And then skipping the 1-byte type encoded by process_heartbeat
159 * for a total of 6 bytes, at which point we can grab the length and the
160 * payload we seek.
161 */
162 fixture.return_payload_offset = 6;
163 return fixture;
164 }
165
tear_down(HEARTBEAT_TEST_FIXTURE fixture)166 static void tear_down(HEARTBEAT_TEST_FIXTURE fixture)
167 {
168 ERR_print_errors_fp(stderr);
169 SSL_free(fixture.s);
170 SSL_CTX_free(fixture.ctx);
171 }
172
print_payload(const char * const prefix,const unsigned char * payload,const int n)173 static void print_payload(const char *const prefix,
174 const unsigned char *payload, const int n)
175 {
176 const int end = n < MAX_PRINTABLE_CHARACTERS ? n
177 : MAX_PRINTABLE_CHARACTERS;
178 int i = 0;
179
180 printf("%s %d character%s", prefix, n, n == 1 ? "" : "s");
181 if (end != n)
182 printf(" (first %d shown)", end);
183 printf("\n \"");
184
185 for (; i != end; ++i) {
186 const unsigned char c = payload[i];
187 if (isprint(c))
188 fputc(c, stdout);
189 else
190 printf("\\x%02x", c);
191 }
192 printf("\"\n");
193 }
194
execute_heartbeat(HEARTBEAT_TEST_FIXTURE fixture)195 static int execute_heartbeat(HEARTBEAT_TEST_FIXTURE fixture)
196 {
197 int result = 0;
198 SSL *s = fixture.s;
199 unsigned char *payload = fixture.payload;
200 unsigned char sent_buf[MAX_PRINTABLE_CHARACTERS + 1];
201 int return_value;
202 unsigned const char *p;
203 int actual_payload_len;
204
205 s->s3->rrec.data = payload;
206 s->s3->rrec.length = strlen((const char *)payload);
207 *payload++ = TLS1_HB_REQUEST;
208 s2n(fixture.sent_payload_len, payload);
209
210 /*
211 * Make a local copy of the request, since it gets overwritten at some
212 * point
213 */
214 memcpy((char *)sent_buf, (const char *)payload, sizeof(sent_buf));
215
216 return_value = fixture.process_heartbeat(s);
217
218 if (return_value != fixture.expected_return_value) {
219 printf("%s failed: expected return value %d, received %d\n",
220 fixture.test_case_name, fixture.expected_return_value,
221 return_value);
222 result = 1;
223 }
224
225 /*
226 * If there is any byte alignment, it will be stored in wbuf.offset.
227 */
228 p = &(s->s3->
229 wbuf.buf[fixture.return_payload_offset + s->s3->wbuf.offset]);
230 actual_payload_len = 0;
231 n2s(p, actual_payload_len);
232
233 if (actual_payload_len != fixture.expected_payload_len) {
234 printf("%s failed:\n expected payload len: %d\n received: %d\n",
235 fixture.test_case_name, fixture.expected_payload_len,
236 actual_payload_len);
237 print_payload("sent", sent_buf, strlen((const char *)sent_buf));
238 print_payload("received", p, actual_payload_len);
239 result = 1;
240 } else {
241 char *actual_payload =
242 BUF_strndup((const char *)p, actual_payload_len);
243 if (strcmp(actual_payload, fixture.expected_return_payload) != 0) {
244 printf
245 ("%s failed:\n expected payload: \"%s\"\n received: \"%s\"\n",
246 fixture.test_case_name, fixture.expected_return_payload,
247 actual_payload);
248 result = 1;
249 }
250 OPENSSL_free(actual_payload);
251 }
252
253 if (result != 0) {
254 printf("** %s failed **\n--------\n", fixture.test_case_name);
255 }
256 return result;
257 }
258
honest_payload_size(unsigned char payload_buf[])259 static int honest_payload_size(unsigned char payload_buf[])
260 {
261 /* Omit three-byte pad at the beginning for type and payload length */
262 return strlen((const char *)&payload_buf[3]) - MIN_PADDING_SIZE;
263 }
264
265 # define SETUP_HEARTBEAT_TEST_FIXTURE(type)\
266 SETUP_TEST_FIXTURE(HEARTBEAT_TEST_FIXTURE, set_up_##type)
267
268 # define EXECUTE_HEARTBEAT_TEST()\
269 EXECUTE_TEST(execute_heartbeat, tear_down)
270
test_dtls1_not_bleeding()271 static int test_dtls1_not_bleeding()
272 {
273 SETUP_HEARTBEAT_TEST_FIXTURE(dtls);
274 /* Three-byte pad at the beginning for type and payload length */
275 unsigned char payload_buf[] = " Not bleeding, sixteen spaces of padding"
276 " ";
277 const int payload_buf_len = honest_payload_size(payload_buf);
278
279 fixture.payload = &payload_buf[0];
280 fixture.sent_payload_len = payload_buf_len;
281 fixture.expected_return_value = 0;
282 fixture.expected_payload_len = payload_buf_len;
283 fixture.expected_return_payload =
284 "Not bleeding, sixteen spaces of padding";
285 EXECUTE_HEARTBEAT_TEST();
286 }
287
test_dtls1_not_bleeding_empty_payload()288 static int test_dtls1_not_bleeding_empty_payload()
289 {
290 int payload_buf_len;
291
292 SETUP_HEARTBEAT_TEST_FIXTURE(dtls);
293 /*
294 * Three-byte pad at the beginning for type and payload length, plus a
295 * NUL at the end
296 */
297 unsigned char payload_buf[4 + MIN_PADDING_SIZE];
298 memset(payload_buf, ' ', sizeof(payload_buf));
299 payload_buf[sizeof(payload_buf) - 1] = '\0';
300 payload_buf_len = honest_payload_size(payload_buf);
301
302 fixture.payload = &payload_buf[0];
303 fixture.sent_payload_len = payload_buf_len;
304 fixture.expected_return_value = 0;
305 fixture.expected_payload_len = payload_buf_len;
306 fixture.expected_return_payload = "";
307 EXECUTE_HEARTBEAT_TEST();
308 }
309
test_dtls1_heartbleed()310 static int test_dtls1_heartbleed()
311 {
312 SETUP_HEARTBEAT_TEST_FIXTURE(dtls);
313 /* Three-byte pad at the beginning for type and payload length */
314 unsigned char payload_buf[] = " HEARTBLEED ";
315
316 fixture.payload = &payload_buf[0];
317 fixture.sent_payload_len = MAX_PRINTABLE_CHARACTERS;
318 fixture.expected_return_value = 0;
319 fixture.expected_payload_len = 0;
320 fixture.expected_return_payload = "";
321 EXECUTE_HEARTBEAT_TEST();
322 }
323
test_dtls1_heartbleed_empty_payload()324 static int test_dtls1_heartbleed_empty_payload()
325 {
326 SETUP_HEARTBEAT_TEST_FIXTURE(dtls);
327 /*
328 * Excluding the NUL at the end, one byte short of type + payload length
329 * + minimum padding
330 */
331 unsigned char payload_buf[MIN_PADDING_SIZE + 3];
332 memset(payload_buf, ' ', sizeof(payload_buf));
333 payload_buf[sizeof(payload_buf) - 1] = '\0';
334
335 fixture.payload = &payload_buf[0];
336 fixture.sent_payload_len = MAX_PRINTABLE_CHARACTERS;
337 fixture.expected_return_value = 0;
338 fixture.expected_payload_len = 0;
339 fixture.expected_return_payload = "";
340 EXECUTE_HEARTBEAT_TEST();
341 }
342
test_dtls1_heartbleed_excessive_plaintext_length()343 static int test_dtls1_heartbleed_excessive_plaintext_length()
344 {
345 SETUP_HEARTBEAT_TEST_FIXTURE(dtls);
346 /*
347 * Excluding the NUL at the end, one byte in excess of maximum allowed
348 * heartbeat message length
349 */
350 unsigned char payload_buf[SSL3_RT_MAX_PLAIN_LENGTH + 2];
351 memset(payload_buf, ' ', sizeof(payload_buf));
352 payload_buf[sizeof(payload_buf) - 1] = '\0';
353
354 fixture.payload = &payload_buf[0];
355 fixture.sent_payload_len = honest_payload_size(payload_buf);
356 fixture.expected_return_value = 0;
357 fixture.expected_payload_len = 0;
358 fixture.expected_return_payload = "";
359 EXECUTE_HEARTBEAT_TEST();
360 }
361
test_tls1_not_bleeding()362 static int test_tls1_not_bleeding()
363 {
364 SETUP_HEARTBEAT_TEST_FIXTURE(tls);
365 /* Three-byte pad at the beginning for type and payload length */
366 unsigned char payload_buf[] = " Not bleeding, sixteen spaces of padding"
367 " ";
368 const int payload_buf_len = honest_payload_size(payload_buf);
369
370 fixture.payload = &payload_buf[0];
371 fixture.sent_payload_len = payload_buf_len;
372 fixture.expected_return_value = 0;
373 fixture.expected_payload_len = payload_buf_len;
374 fixture.expected_return_payload =
375 "Not bleeding, sixteen spaces of padding";
376 EXECUTE_HEARTBEAT_TEST();
377 }
378
test_tls1_not_bleeding_empty_payload()379 static int test_tls1_not_bleeding_empty_payload()
380 {
381 int payload_buf_len;
382
383 SETUP_HEARTBEAT_TEST_FIXTURE(tls);
384 /*
385 * Three-byte pad at the beginning for type and payload length, plus a
386 * NUL at the end
387 */
388 unsigned char payload_buf[4 + MIN_PADDING_SIZE];
389 memset(payload_buf, ' ', sizeof(payload_buf));
390 payload_buf[sizeof(payload_buf) - 1] = '\0';
391 payload_buf_len = honest_payload_size(payload_buf);
392
393 fixture.payload = &payload_buf[0];
394 fixture.sent_payload_len = payload_buf_len;
395 fixture.expected_return_value = 0;
396 fixture.expected_payload_len = payload_buf_len;
397 fixture.expected_return_payload = "";
398 EXECUTE_HEARTBEAT_TEST();
399 }
400
test_tls1_heartbleed()401 static int test_tls1_heartbleed()
402 {
403 SETUP_HEARTBEAT_TEST_FIXTURE(tls);
404 /* Three-byte pad at the beginning for type and payload length */
405 unsigned char payload_buf[] = " HEARTBLEED ";
406
407 fixture.payload = &payload_buf[0];
408 fixture.sent_payload_len = MAX_PRINTABLE_CHARACTERS;
409 fixture.expected_return_value = 0;
410 fixture.expected_payload_len = 0;
411 fixture.expected_return_payload = "";
412 EXECUTE_HEARTBEAT_TEST();
413 }
414
test_tls1_heartbleed_empty_payload()415 static int test_tls1_heartbleed_empty_payload()
416 {
417 SETUP_HEARTBEAT_TEST_FIXTURE(tls);
418 /*
419 * Excluding the NUL at the end, one byte short of type + payload length
420 * + minimum padding
421 */
422 unsigned char payload_buf[MIN_PADDING_SIZE + 3];
423 memset(payload_buf, ' ', sizeof(payload_buf));
424 payload_buf[sizeof(payload_buf) - 1] = '\0';
425
426 fixture.payload = &payload_buf[0];
427 fixture.sent_payload_len = MAX_PRINTABLE_CHARACTERS;
428 fixture.expected_return_value = 0;
429 fixture.expected_payload_len = 0;
430 fixture.expected_return_payload = "";
431 EXECUTE_HEARTBEAT_TEST();
432 }
433
434 # undef EXECUTE_HEARTBEAT_TEST
435 # undef SETUP_HEARTBEAT_TEST_FIXTURE
436
main(int argc,char * argv[])437 int main(int argc, char *argv[])
438 {
439 int num_failed;
440
441 SSL_library_init();
442 SSL_load_error_strings();
443
444 num_failed = test_dtls1_not_bleeding() +
445 test_dtls1_not_bleeding_empty_payload() +
446 test_dtls1_heartbleed() + test_dtls1_heartbleed_empty_payload() +
447 /*
448 * The following test causes an assertion failure at
449 * ssl/d1_pkt.c:dtls1_write_bytes() in versions prior to 1.0.1g:
450 */
451 (OPENSSL_VERSION_NUMBER >= 0x1000107fL ?
452 test_dtls1_heartbleed_excessive_plaintext_length() : 0) +
453 test_tls1_not_bleeding() +
454 test_tls1_not_bleeding_empty_payload() +
455 test_tls1_heartbleed() + test_tls1_heartbleed_empty_payload() + 0;
456
457 ERR_print_errors_fp(stderr);
458
459 if (num_failed != 0) {
460 printf("%d test%s failed\n", num_failed, num_failed != 1 ? "s" : "");
461 return EXIT_FAILURE;
462 }
463 return EXIT_SUCCESS;
464 }
465
466 #else /* OPENSSL_NO_HEARTBEATS */
467
main(int argc,char * argv[])468 int main(int argc, char *argv[])
469 {
470 return EXIT_SUCCESS;
471 }
472 #endif /* OPENSSL_NO_HEARTBEATS */
473