1/*
2 * Copyright (c) 2017 Thomas Pornin <pornin@bolet.org>
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining
5 * a copy of this software and associated documentation files (the
6 * "Software"), to deal in the Software without restriction, including
7 * without limitation the rights to use, copy, modify, merge, publish,
8 * distribute, sublicense, and/or sell copies of the Software, and to
9 * permit persons to whom the Software is furnished to do so, subject to
10 * the following conditions:
11 *
12 * The above copyright notice and this permission notice shall be
13 * included in all copies or substantial portions of the Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
16 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
17 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
18 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
19 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
20 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
21 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
22 * SOFTWARE.
23 */
24
25#include <stdio.h>
26#include <stdlib.h>
27#include <string.h>
28#include <stdint.h>
29#include <errno.h>
30
31#ifdef _WIN32
32#include <windows.h>
33#else
34#include <signal.h>
35#include <sys/types.h>
36#include <unistd.h>
37#endif
38
39#include "brssl.h"
40
41static int verbose = 0;
42
43static void
44usage_twrch(void)
45{
46	fprintf(stderr,
47"usage: brssl twrch [ options ]\n");
48	fprintf(stderr,
49"options:\n");
50	fprintf(stderr,
51"   -trace          dump all packets on stderr\n");
52	fprintf(stderr,
53"   -v              verbose error messages on stderr\n");
54	fprintf(stderr,
55"   -server         act as an SSL server\n");
56	fprintf(stderr,
57"   -client         act as an SSL client\n");
58	fprintf(stderr,
59"   -sni name       use specified name for SNI\n");
60	fprintf(stderr,
61"   -mono           use monodirectional buffering\n");
62	fprintf(stderr,
63"   -buf length     set the I/O buffer length (in bytes)\n");
64	fprintf(stderr,
65"   -cache length   set the session cache storage length (in bytes)\n");
66	fprintf(stderr,
67"   -cert fname     read certificate chain from file 'fname'\n");
68	fprintf(stderr,
69"   -key fname      read private key from file 'fname'\n");
70	fprintf(stderr,
71"   -CA file        add trust anchors from 'file' (for peer auth)\n");
72	fprintf(stderr,
73"   -anon_ok        request but do not require a client certificate\n");
74	fprintf(stderr,
75"   -nostaticecdh   prohibit full-static ECDH (client only)\n");
76	fprintf(stderr,
77"   -list           list supported names (protocols, algorithms...)\n");
78	fprintf(stderr,
79"   -vmin name      set minimum supported version (default: TLS-1.0)\n");
80	fprintf(stderr,
81"   -vmax name      set maximum supported version (default: TLS-1.2)\n");
82	fprintf(stderr,
83"   -cs names       set list of supported cipher suites (comma-separated)\n");
84	fprintf(stderr,
85"   -hf names       add support for some hash functions (comma-separated)\n");
86	fprintf(stderr,
87"   -minhello len   set minimum ClientHello length (in bytes)\n");
88	fprintf(stderr,
89"   -serverpref     enforce server's preferences for cipher suites\n");
90	fprintf(stderr,
91"   -noreneg        prohibit renegotiations\n");
92	fprintf(stderr,
93"   -alpn name      add protocol name to list of protocols (ALPN extension)\n");
94	fprintf(stderr,
95"   -strictalpn     fail on ALPN mismatch\n");
96}
97
98static void
99free_alpn(void *alpn)
100{
101	xfree(*(char **)alpn);
102}
103
104static void
105dump_blob(const char *name, const void *data, size_t len)
106{
107	const unsigned char *buf;
108	size_t u;
109
110	buf = data;
111	fprintf(stderr, "%s (len = %lu)", name, (unsigned long)len);
112	for (u = 0; u < len; u ++) {
113		if ((u & 15) == 0) {
114			fprintf(stderr, "\n%08lX  ", (unsigned long)u);
115		} else if ((u & 7) == 0) {
116			fprintf(stderr, " ");
117		}
118		fprintf(stderr, " %02x", buf[u]);
119	}
120	fprintf(stderr, "\n");
121}
122
123/*
124 * Callback for reading bytes from standard input.
125 */
126static int
127stdin_read(void *ctx, unsigned char *buf, size_t len)
128{
129	for (;;) {
130#ifdef _WIN32
131		DWORD rlen;
132#else
133		ssize_t rlen;
134#endif
135		int eof;
136
137#ifdef _WIN32
138		eof = !ReadFile(GetStdHandle(STD_INPUT_HANDLE),
139			buf, len, &rlen, NULL) || rlen == 0;
140#else
141		rlen = read(0, buf, len);
142		if (rlen <= 0) {
143			if (rlen < 0 && errno == EINTR) {
144				continue;
145			}
146			eof = 1;
147		} else {
148			eof = 0;
149		}
150#endif
151		if (eof) {
152			if (*(int *)ctx) {
153				if (verbose) {
154					fprintf(stderr, "recv: EOF\n");
155				}
156			}
157			return -1;
158		}
159		if (*(int *)ctx) {
160			dump_blob("recv", buf, (size_t)rlen);
161		}
162		return (int)rlen;
163	}
164}
165
166/*
167 * Callback for writing bytes on standard output.
168 */
169static int
170stdout_write(void *ctx, const unsigned char *buf, size_t len)
171{
172	for (;;) {
173#ifdef _WIN32
174		DWORD wlen;
175#else
176		ssize_t wlen;
177#endif
178		int eof;
179
180#ifdef _WIN32
181		eof = !WriteFile(GetStdHandle(STD_OUTPUT_HANDLE),
182			buf, len, &wlen, NULL);
183#else
184		wlen = write(1, buf, len);
185		if (wlen <= 0) {
186			if (wlen < 0 && errno == EINTR) {
187				continue;
188			}
189			eof = 1;
190		} else {
191			eof = 0;
192		}
193#endif
194		if (eof) {
195			if (*(int *)ctx) {
196				if (verbose) {
197					fprintf(stderr, "send: EOF\n");
198				}
199			}
200			return -1;
201		}
202		if (*(int *)ctx) {
203			dump_blob("send", buf, (size_t)wlen);
204		}
205		return (int)wlen;
206	}
207}
208
209static void
210print_error(int err)
211{
212	const char *name, *comment;
213
214	name = find_error_name(err, &comment);
215	if (name != NULL) {
216		fprintf(stderr, "ERR %d: %s\n   %s\n", err, name, comment);
217		return;
218	}
219	if (err >= BR_ERR_RECV_FATAL_ALERT
220		&& err < BR_ERR_RECV_FATAL_ALERT + 256)
221	{
222		fprintf(stderr, "ERR %d: received fatal alert %d\n",
223			err, err - BR_ERR_RECV_FATAL_ALERT);
224		return;
225	}
226	if (err >= BR_ERR_SEND_FATAL_ALERT
227		&& err < BR_ERR_SEND_FATAL_ALERT + 256)
228	{
229		fprintf(stderr, "ERR %d: sent fatal alert %d\n",
230			err, err - BR_ERR_SEND_FATAL_ALERT);
231		return;
232	}
233	fprintf(stderr, "ERR %d: UNKNOWN\n", err);
234}
235
236/* see brssl.h */
237int
238do_twrch(int argc, char *argv[])
239{
240	int retcode;
241	int trace;
242	int is_client;
243	int is_server;
244	const char *sni;
245	int i, bidi;
246	unsigned vmin, vmax;
247	cipher_suite *suites;
248	size_t num_suites;
249	uint16_t *suite_ids;
250	unsigned hfuns;
251	br_x509_certificate *chain;
252	size_t chain_len;
253	int cert_signer_algo;
254	private_key *sk;
255	int nostaticecdh;
256	anchor_list anchors = VEC_INIT;
257	VECTOR(char *) alpn_names = VEC_INIT;
258	br_x509_minimal_context xc;
259	x509_noanchor_context xwc;
260	const br_hash_class *dnhash;
261	size_t u;
262	union {
263		br_ssl_engine_context eng;
264		br_ssl_server_context srv;
265		br_ssl_client_context cnt;
266	} cc;
267	br_ssl_session_cache_lru lru;
268	unsigned char *iobuf, *cache;
269	size_t iobuf_len, cache_len, minhello_len;
270	br_sslio_context ioc;
271	uint32_t flags;
272	int reconnect;
273
274	retcode = 0;
275	trace = 0;
276	is_client = 0;
277	is_server = 0;
278	sni = NULL;
279	bidi = 1;
280	vmin = 0;
281	vmax = 0;
282	suites = NULL;
283	num_suites = 0;
284	suite_ids = NULL;
285	hfuns = 0;
286	chain = NULL;
287	chain_len = 0;
288	cert_signer_algo = 0;
289	sk = NULL;
290	nostaticecdh = 0;
291	iobuf = NULL;
292	iobuf_len = 0;
293	cache = NULL;
294	cache_len = (size_t)-1;
295	minhello_len = (size_t)-1;
296	flags = 0;
297	reconnect = 0;
298	for (i = 0; i < argc; i ++) {
299		const char *arg;
300
301		arg = argv[i];
302		if (arg[0] != '-') {
303			usage_twrch();
304			goto twrch_exit_error;
305		}
306		if (eqstr(arg, "-trace")) {
307			trace = 1;
308		} else if (eqstr(arg, "-v")) {
309			verbose = 1;
310		} else if (eqstr(arg, "-server")) {
311			is_server = 1;
312		} else if (eqstr(arg, "-client")) {
313			is_client = 1;
314		} else if (eqstr(arg, "-sni")) {
315			if (++ i >= argc) {
316				fprintf(stderr,
317					"ERROR: no argument for '-sni'\n");
318				usage_twrch();
319				goto twrch_exit_error;
320			}
321			arg = argv[i];
322			if (sni != NULL) {
323				fprintf(stderr, "ERROR: duplicate SNI\n");
324				usage_twrch();
325				goto twrch_exit_error;
326			}
327			sni = arg;
328		} else if (eqstr(arg, "-mono")) {
329			bidi = 0;
330		} else if (eqstr(arg, "-buf")) {
331			if (++ i >= argc) {
332				fprintf(stderr,
333					"ERROR: no argument for '-buf'\n");
334				usage_twrch();
335				goto twrch_exit_error;
336			}
337			arg = argv[i];
338			if (iobuf_len != 0) {
339				fprintf(stderr,
340					"ERROR: duplicate I/O buffer length\n");
341				usage_twrch();
342				goto twrch_exit_error;
343			}
344			iobuf_len = parse_size(arg);
345			if (iobuf_len == (size_t)-1) {
346				usage_twrch();
347				goto twrch_exit_error;
348			}
349		} else if (eqstr(arg, "-cache")) {
350			if (++ i >= argc) {
351				fprintf(stderr,
352					"ERROR: no argument for '-cache'\n");
353				usage_twrch();
354				goto twrch_exit_error;
355			}
356			arg = argv[i];
357			if (cache_len != (size_t)-1) {
358				fprintf(stderr, "ERROR: duplicate session"
359					" cache length\n");
360				usage_twrch();
361				goto twrch_exit_error;
362			}
363			cache_len = parse_size(arg);
364			if (cache_len == (size_t)-1) {
365				usage_twrch();
366				goto twrch_exit_error;
367			}
368		} else if (eqstr(arg, "-cert")) {
369			if (++ i >= argc) {
370				fprintf(stderr,
371					"ERROR: no argument for '-cert'\n");
372				usage_twrch();
373				goto twrch_exit_error;
374			}
375			if (chain != NULL) {
376				fprintf(stderr,
377					"ERROR: duplicate certificate chain\n");
378				usage_twrch();
379				goto twrch_exit_error;
380			}
381			arg = argv[i];
382			chain = read_certificates(arg, &chain_len);
383			if (chain == NULL || chain_len == 0) {
384				goto twrch_exit_error;
385			}
386		} else if (eqstr(arg, "-key")) {
387			if (++ i >= argc) {
388				fprintf(stderr,
389					"ERROR: no argument for '-key'\n");
390				usage_twrch();
391				goto twrch_exit_error;
392			}
393			if (sk != NULL) {
394				fprintf(stderr,
395					"ERROR: duplicate private key\n");
396				usage_twrch();
397				goto twrch_exit_error;
398			}
399			arg = argv[i];
400			sk = read_private_key(arg);
401			if (sk == NULL) {
402				goto twrch_exit_error;
403			}
404		} else if (eqstr(arg, "-CA")) {
405			if (++ i >= argc) {
406				fprintf(stderr,
407					"ERROR: no argument for '-CA'\n");
408				usage_twrch();
409				goto twrch_exit_error;
410			}
411			arg = argv[i];
412			if (read_trust_anchors(&anchors, arg) == 0) {
413				usage_twrch();
414				goto twrch_exit_error;
415			}
416		} else if (eqstr(arg, "-anon_ok")) {
417			flags |= BR_OPT_TOLERATE_NO_CLIENT_AUTH;
418		} else if (eqstr(arg, "-nostaticecdh")) {
419			nostaticecdh = 1;
420		} else if (eqstr(arg, "-list")) {
421			list_names();
422			goto twrch_exit;
423		} else if (eqstr(arg, "-vmin")) {
424			if (++ i >= argc) {
425				fprintf(stderr,
426					"ERROR: no argument for '-vmin'\n");
427				usage_twrch();
428				goto twrch_exit_error;
429			}
430			arg = argv[i];
431			if (vmin != 0) {
432				fprintf(stderr,
433					"ERROR: duplicate minimum version\n");
434				usage_twrch();
435				goto twrch_exit_error;
436			}
437			vmin = parse_version(arg, strlen(arg));
438			if (vmin == 0) {
439				fprintf(stderr,
440					"ERROR: unrecognised version '%s'\n",
441					arg);
442				usage_twrch();
443				goto twrch_exit_error;
444			}
445		} else if (eqstr(arg, "-vmax")) {
446			if (++ i >= argc) {
447				fprintf(stderr,
448					"ERROR: no argument for '-vmax'\n");
449				usage_twrch();
450				goto twrch_exit_error;
451			}
452			arg = argv[i];
453			if (vmax != 0) {
454				fprintf(stderr,
455					"ERROR: duplicate maximum version\n");
456				usage_twrch();
457				goto twrch_exit_error;
458			}
459			vmax = parse_version(arg, strlen(arg));
460			if (vmax == 0) {
461				fprintf(stderr,
462					"ERROR: unrecognised version '%s'\n",
463					arg);
464				usage_twrch();
465				goto twrch_exit_error;
466			}
467		} else if (eqstr(arg, "-cs")) {
468			if (++ i >= argc) {
469				fprintf(stderr,
470					"ERROR: no argument for '-cs'\n");
471				usage_twrch();
472				goto twrch_exit_error;
473			}
474			arg = argv[i];
475			if (suites != NULL) {
476				fprintf(stderr, "ERROR: duplicate list"
477					" of cipher suites\n");
478				usage_twrch();
479				goto twrch_exit_error;
480			}
481			suites = parse_suites(arg, &num_suites);
482			if (suites == NULL) {
483				usage_twrch();
484				goto twrch_exit_error;
485			}
486		} else if (eqstr(arg, "-hf")) {
487			unsigned x;
488
489			if (++ i >= argc) {
490				fprintf(stderr,
491					"ERROR: no argument for '-hf'\n");
492				usage_twrch();
493				goto twrch_exit_error;
494			}
495			arg = argv[i];
496			x = parse_hash_functions(arg);
497			if (x == 0) {
498				usage_twrch();
499				goto twrch_exit_error;
500			}
501			hfuns |= x;
502		} else if (eqstr(arg, "-minhello")) {
503			if (++ i >= argc) {
504				fprintf(stderr,
505					"ERROR: no argument for '-minhello'\n");
506				usage_twrch();
507				goto twrch_exit_error;
508			}
509			arg = argv[i];
510			if (minhello_len != (size_t)-1) {
511				fprintf(stderr, "ERROR: duplicate minimum"
512					" ClientHello length\n");
513				usage_twrch();
514				goto twrch_exit_error;
515			}
516			minhello_len = parse_size(arg);
517			/*
518			 * Minimum ClientHello length must fit on 16 bits.
519			 */
520			if (minhello_len == (size_t)-1
521				|| (((minhello_len >> 12) >> 4) != 0))
522			{
523				usage_twrch();
524				goto twrch_exit_error;
525			}
526		} else if (eqstr(arg, "-serverpref")) {
527			flags |= BR_OPT_ENFORCE_SERVER_PREFERENCES;
528		} else if (eqstr(arg, "-noreneg")) {
529			flags |= BR_OPT_NO_RENEGOTIATION;
530		} else if (eqstr(arg, "-alpn")) {
531			if (++ i >= argc) {
532				fprintf(stderr,
533					"ERROR: no argument for '-alpn'\n");
534				usage_twrch();
535				goto twrch_exit_error;
536			}
537			VEC_ADD(alpn_names, xstrdup(argv[i]));
538		} else if (eqstr(arg, "-strictalpn")) {
539			flags |= BR_OPT_FAIL_ON_ALPN_MISMATCH;
540		} else {
541			fprintf(stderr, "ERROR: unknown option: '%s'\n", arg);
542			usage_twrch();
543			goto twrch_exit_error;
544		}
545	}
546
547	/*
548	 * Verify consistency of options.
549	 */
550	if (!is_client && !is_server) {
551		fprintf(stderr, "ERROR:"
552			" one of -server and -client must be specified\n");
553		usage_twrch();
554		goto twrch_exit_error;
555	}
556	if (is_client && is_server) {
557		fprintf(stderr, "ERROR:"
558			" -server and -client may not be both specified\n");
559		usage_twrch();
560		goto twrch_exit_error;
561	}
562
563	if (vmin == 0) {
564		vmin = BR_TLS10;
565	}
566	if (vmax == 0) {
567		vmax = BR_TLS12;
568	}
569	if (vmax < vmin) {
570		fprintf(stderr, "ERROR: impossible minimum/maximum protocol"
571			" version combination\n");
572		usage_twrch();
573		goto twrch_exit_error;
574	}
575	if (is_server) {
576		if (chain == NULL) {
577			fprintf(stderr, "ERROR: no certificate specified"
578				" for server (-cert)\n");
579			usage_twrch();
580			goto twrch_exit_error;
581		}
582		if (sk == NULL) {
583			fprintf(stderr, "ERROR: no private key specified"
584				" for server (-key)\n");
585			usage_twrch();
586			goto twrch_exit_error;
587		}
588	} else {
589		if (chain == NULL && sk != NULL) {
590			fprintf(stderr, "ERROR: private key (-key)"
591				" but no certificate (-cert)");
592			usage_twrch();
593			goto twrch_exit_error;
594		}
595		if (chain != NULL && sk == NULL) {
596			fprintf(stderr, "ERROR: certificate (-cert)"
597				" but no private key (-key)");
598			usage_twrch();
599			goto twrch_exit_error;
600		}
601	}
602	if (suites == NULL) {
603		num_suites = 0;
604
605		for (u = 0; cipher_suites[u].name; u ++) {
606			if ((cipher_suites[u].req & REQ_TLS12) == 0
607				|| vmax >= BR_TLS12)
608			{
609				num_suites ++;
610			}
611		}
612		suites = xmalloc(num_suites * sizeof *suites);
613		num_suites = 0;
614		for (u = 0; cipher_suites[u].name; u ++) {
615			if ((cipher_suites[u].req & REQ_TLS12) == 0
616				|| vmax >= BR_TLS12)
617			{
618				suites[num_suites ++] = cipher_suites[u];
619			}
620		}
621	}
622	if (hfuns == 0) {
623		hfuns = (unsigned)-1;
624	}
625	if (sk != NULL) {
626		switch (sk->key_type) {
627			int curve;
628			uint32_t supp;
629
630		case BR_KEYTYPE_RSA:
631			break;
632		case BR_KEYTYPE_EC:
633			curve = sk->key.ec.curve;
634			supp = br_ec_get_default()->supported_curves;
635			if (curve > 31 || !((supp >> curve) & 1)) {
636				fprintf(stderr, "ERROR: private key curve (%d)"
637					" is not supported\n", curve);
638				goto twrch_exit_error;
639			}
640			break;
641		default:
642			fprintf(stderr, "ERROR: unsupported"
643				" private key type (%d)\n", sk->key_type);
644			goto twrch_exit_error;
645		}
646	}
647	if (chain != NULL) {
648		cert_signer_algo = get_cert_signer_algo(chain);
649		if (cert_signer_algo == 0) {
650			goto twrch_exit_error;
651		}
652	}
653	if (iobuf_len == 0) {
654		if (bidi) {
655			iobuf_len = BR_SSL_BUFSIZE_BIDI;
656		} else {
657			iobuf_len = BR_SSL_BUFSIZE_MONO;
658		}
659	}
660	iobuf = xmalloc(iobuf_len);
661	if (is_server) {
662		if (cache_len == (size_t)-1) {
663			cache_len = 5000;
664		}
665		cache = xmalloc(cache_len);
666	}
667
668	/*
669	 * Initialise the relevant context.
670	 */
671	if (is_client) {
672		br_ssl_client_zero(&cc.cnt);
673	} else {
674		br_ssl_server_zero(&cc.srv);
675	}
676
677	/*
678	 * Compute implementation requirements and inject implementations.
679	 */
680	suite_ids = xmalloc(num_suites * sizeof *suite_ids);
681	br_ssl_engine_set_versions(&cc.eng, vmin, vmax);
682	br_ssl_engine_set_all_flags(&cc.eng, flags);
683	if (vmin <= BR_TLS11) {
684		if (!(hfuns & (1 << br_md5_ID))) {
685			fprintf(stderr, "ERROR: TLS 1.0 and 1.1 need MD5\n");
686			goto twrch_exit_error;
687		}
688		if (!(hfuns & (1 << br_sha1_ID))) {
689			fprintf(stderr, "ERROR: TLS 1.0 and 1.1 need SHA-1\n");
690			goto twrch_exit_error;
691		}
692	}
693	for (u = 0; u < num_suites; u ++) {
694		unsigned req;
695
696		req = suites[u].req;
697		suite_ids[u] = suites[u].suite;
698		if ((req & REQ_TLS12) != 0 && vmax < BR_TLS12) {
699			fprintf(stderr,
700				"ERROR: cipher suite %s requires TLS 1.2\n",
701				suites[u].name);
702			goto twrch_exit_error;
703		}
704		if ((req & REQ_SHA1) != 0 && !(hfuns & (1 << br_sha1_ID))) {
705			fprintf(stderr,
706				"ERROR: cipher suite %s requires SHA-1\n",
707				suites[u].name);
708			goto twrch_exit_error;
709		}
710		if ((req & REQ_SHA256) != 0 && !(hfuns & (1 << br_sha256_ID))) {
711			fprintf(stderr,
712				"ERROR: cipher suite %s requires SHA-256\n",
713				suites[u].name);
714			goto twrch_exit_error;
715		}
716		if ((req & REQ_SHA384) != 0 && !(hfuns & (1 << br_sha384_ID))) {
717			fprintf(stderr,
718				"ERROR: cipher suite %s requires SHA-384\n",
719				suites[u].name);
720			goto twrch_exit_error;
721		}
722		/* TODO: algorithm implementation selection */
723		if ((req & REQ_AESCBC) != 0) {
724			br_ssl_engine_set_default_aes_cbc(&cc.eng);
725		}
726		if ((req & REQ_AESCCM) != 0) {
727			br_ssl_engine_set_default_aes_ccm(&cc.eng);
728		}
729		if ((req & REQ_AESGCM) != 0) {
730			br_ssl_engine_set_default_aes_gcm(&cc.eng);
731		}
732		if ((req & REQ_CHAPOL) != 0) {
733			br_ssl_engine_set_default_chapol(&cc.eng);
734		}
735		if ((req & REQ_3DESCBC) != 0) {
736			br_ssl_engine_set_default_des_cbc(&cc.eng);
737		}
738		if (is_client && (req & REQ_RSAKEYX) != 0) {
739			br_ssl_client_set_default_rsapub(&cc.cnt);
740		}
741		if (is_client && (req & REQ_ECDHE_RSA) != 0) {
742			br_ssl_engine_set_default_rsavrfy(&cc.eng);
743		}
744		if (is_client && (req & REQ_ECDH) != 0) {
745			br_ssl_engine_set_default_ec(&cc.eng);
746		}
747		if ((req & (REQ_ECDHE_RSA | REQ_ECDHE_ECDSA)) != 0) {
748			br_ssl_engine_set_default_ec(&cc.eng);
749		}
750	}
751	br_ssl_engine_set_suites(&cc.eng, suite_ids, num_suites);
752
753	dnhash = NULL;
754	for (u = 0; hash_functions[u].name; u ++) {
755		const br_hash_class *hc;
756		int id;
757
758		hc = hash_functions[u].hclass;
759		id = (hc->desc >> BR_HASHDESC_ID_OFF) & BR_HASHDESC_ID_MASK;
760		if ((hfuns & ((unsigned)1 << id)) != 0) {
761			dnhash = hc;
762			br_ssl_engine_set_hash(&cc.eng, id, hc);
763		}
764	}
765	if (vmin <= BR_TLS11) {
766		br_ssl_engine_set_prf10(&cc.eng, &br_tls10_prf);
767	}
768	if (vmax >= BR_TLS12) {
769		if ((hfuns & ((unsigned)1 << br_sha256_ID)) != 0) {
770			br_ssl_engine_set_prf_sha256(&cc.eng,
771				&br_tls12_sha256_prf);
772		}
773		if ((hfuns & ((unsigned)1 << br_sha384_ID)) != 0) {
774			br_ssl_engine_set_prf_sha384(&cc.eng,
775				&br_tls12_sha384_prf);
776		}
777	}
778	if (VEC_LEN(alpn_names) != 0) {
779		br_ssl_engine_set_protocol_names(&cc.eng,
780			(const char **)&VEC_ELT(alpn_names, 0),
781			VEC_LEN(alpn_names));
782	}
783
784	/*
785	 * In server role, we use a session cache (size can be
786	 * specified; if size is zero, then no cache is set).
787	 */
788	if (is_server && cache != NULL) {
789		br_ssl_session_cache_lru_init(&lru, cache, cache_len);
790		br_ssl_server_set_cache(&cc.srv, &lru.vtable);
791	}
792
793	/*
794	 * For a server, set the policy handler.
795	 */
796	if (is_server) {
797		switch (sk->key_type) {
798		case BR_KEYTYPE_RSA:
799			br_ssl_server_set_single_rsa(&cc.srv,
800				chain, chain_len, &sk->key.rsa,
801				BR_KEYTYPE_KEYX | BR_KEYTYPE_SIGN,
802				br_rsa_private_get_default(),
803				br_rsa_pkcs1_sign_get_default());
804			break;
805		case BR_KEYTYPE_EC:
806			br_ssl_server_set_single_ec(&cc.srv,
807				chain, chain_len, &sk->key.ec,
808				BR_KEYTYPE_KEYX | BR_KEYTYPE_SIGN,
809				cert_signer_algo,
810				br_ec_get_default(),
811				br_ecdsa_sign_asn1_get_default());
812			break;
813		default:
814			fprintf(stderr, "ERROR: unsupported"
815				" private key type (%d)\n", sk->key_type);
816			goto twrch_exit_error;
817		}
818	}
819
820	/*
821	 * For a client, if a certificate was specified, use it.
822	 */
823	if (is_client && chain != NULL) {
824		switch (sk->key_type) {
825			unsigned usages;
826
827		case BR_KEYTYPE_RSA:
828			br_ssl_client_set_single_rsa(&cc.cnt,
829				chain, chain_len, &sk->key.rsa,
830				br_rsa_pkcs1_sign_get_default());
831			break;
832		case BR_KEYTYPE_EC:
833			if (nostaticecdh) {
834				cert_signer_algo = 0;
835				usages = BR_KEYTYPE_SIGN;
836			} else {
837				usages = BR_KEYTYPE_KEYX | BR_KEYTYPE_SIGN;
838			}
839			br_ssl_client_set_single_ec(&cc.cnt,
840				chain, chain_len, &sk->key.ec,
841				usages, cert_signer_algo,
842				br_ec_get_default(),
843				br_ecdsa_sign_asn1_get_default());
844			break;
845		default:
846			fprintf(stderr, "ERROR: unsupported"
847				" private key type (%d)\n", sk->key_type);
848			goto twrch_exit_error;
849		}
850	}
851
852	/*
853	 * On a client, or if trust anchors have been configured, then
854	 * set an X.509 validation engine. If there are no trust anchors
855	 * (client only), then a "no anchor" wrapper will be applied.
856	 */
857	if (is_client || VEC_LEN(anchors) != 0) {
858		br_x509_minimal_init(&xc, dnhash,
859			&VEC_ELT(anchors, 0), VEC_LEN(anchors));
860		for (u = 0; hash_functions[u].name; u ++) {
861			const br_hash_class *hc;
862			int id;
863
864			hc = hash_functions[u].hclass;
865			id = (hc->desc >> BR_HASHDESC_ID_OFF)
866				& BR_HASHDESC_ID_MASK;
867			if ((hfuns & ((unsigned)1 << id)) != 0) {
868				br_x509_minimal_set_hash(&xc, id, hc);
869			}
870		}
871		br_ssl_engine_set_default_rsavrfy(&cc.eng);
872		br_ssl_engine_set_default_ecdsa(&cc.eng);
873		br_x509_minimal_set_rsa(&xc, br_rsa_pkcs1_vrfy_get_default());
874		br_x509_minimal_set_ecdsa(&xc,
875			br_ec_get_default(), br_ecdsa_vrfy_asn1_get_default());
876		br_ssl_engine_set_x509(&cc.eng, &xc.vtable);
877
878		if (VEC_LEN(anchors) == 0) {
879			x509_noanchor_init(&xwc, &xc.vtable);
880			br_ssl_engine_set_x509(&cc.eng, &xwc.vtable);
881		} else {
882			br_ssl_engine_set_x509(&cc.eng, &xc.vtable);
883		}
884		if (is_server) {
885			br_ssl_server_set_trust_anchor_names_alt(&cc.srv,
886				&VEC_ELT(anchors, 0), VEC_LEN(anchors));
887		}
888	}
889
890	/*
891	 * Set I/O buffer.
892	 */
893	br_ssl_engine_set_buffer(&cc.eng, iobuf, iobuf_len, bidi);
894
895	/*
896	 * Start the engine.
897	 */
898	if (is_client) {
899		br_ssl_client_reset(&cc.cnt, sni, 0);
900	}
901	if (is_server) {
902		br_ssl_server_reset(&cc.srv);
903	}
904
905	/*
906	 * On Unix systems, we want to ignore SIGPIPE: if the peer
907	 * closes the connection abruptly, then we want to report it
908	 * as a "normal" error (exit code = 1).
909	 */
910#ifndef _WIN32
911	signal(SIGPIPE, SIG_IGN);
912#endif
913
914	/*
915	 * Initialize the callbacks for exchanging data over stdin and
916	 * stdout.
917	 */
918	br_sslio_init(&ioc, &cc.eng, stdin_read, &trace, stdout_write, &trace);
919
920	/*
921	 * Run the Twrch protocol.
922	 */
923	for (;;) {
924		br_sha1_context sc;
925		unsigned char hv[20], tmp[41];
926		uint64_t count;
927		int fb, i;
928
929		/*
930		 * Read line, byte by byte, hashing it on the fly.
931		 */
932		br_sha1_init(&sc);
933		count = 0;
934		fb = 0;
935		for (;;) {
936			unsigned char x;
937
938			if (br_sslio_read(&ioc, &x, 1) < 0) {
939				if (count == 0 && reconnect) {
940					reconnect = 0;
941					if (br_sslio_close(&ioc) < 0) {
942						goto twrch_loop_finished;
943					}
944					if (is_client) {
945						br_ssl_client_reset(
946							&cc.cnt, sni, 1);
947					}
948					if (is_server) {
949						br_ssl_server_reset(&cc.srv);
950					}
951					br_sslio_init(&ioc, &cc.eng,
952						stdin_read, &trace,
953						stdout_write, &trace);
954					continue;
955				}
956				goto twrch_loop_finished;
957			}
958			if (count == 0) {
959				fb = x;
960			}
961			if (x == 0x0A) {
962				break;
963			}
964			br_sha1_update(&sc, &x, 1);
965			count ++;
966		}
967		if (count == 1) {
968			switch (fb) {
969			case 'C':
970				br_sslio_close(&ioc);
971				goto twrch_loop_finished;
972			case 'T':
973				if (br_sslio_close(&ioc) < 0) {
974					goto twrch_loop_finished;
975				}
976				if (is_client) {
977					br_ssl_client_reset(&cc.cnt, sni, 1);
978				}
979				if (is_server) {
980					br_ssl_server_reset(&cc.srv);
981				}
982				br_sslio_init(&ioc, &cc.eng,
983					stdin_read, &trace,
984					stdout_write, &trace);
985				continue;
986			case 'G':
987				if (!br_ssl_engine_renegotiate(&cc.eng)) {
988					br_sslio_write_all(&ioc, "DENIED\n", 7);
989					br_sslio_flush(&ioc);
990				} else {
991					br_sslio_write_all(&ioc, "OK\n", 3);
992					br_sslio_flush(&ioc);
993				}
994				continue;
995			case 'R':
996				reconnect = 1;
997				br_sslio_write_all(&ioc, "OK\n", 3);
998				br_sslio_flush(&ioc);
999				continue;
1000			case 'U':
1001				if (is_client) {
1002					br_ssl_client_forget_session(&cc.cnt);
1003				}
1004				if (is_server && cache != NULL) {
1005					br_ssl_session_parameters pp;
1006
1007					br_ssl_engine_get_session_parameters(
1008						&cc.eng, &pp);
1009					if (pp.session_id_len == 32) {
1010						br_ssl_session_cache_lru_forget(
1011							&lru, pp.session_id);
1012					}
1013				}
1014				br_sslio_write_all(&ioc, "DONE\n", 5);
1015				br_sslio_flush(&ioc);
1016				continue;
1017			}
1018		}
1019		br_sha1_out(&sc, hv);
1020		for (i = 0; i < 20; i ++) {
1021			int x;
1022
1023			x = hv[i];
1024			tmp[(i << 1) + 0] = "0123456789abcdef"[x >> 4];
1025			tmp[(i << 1) + 1] = "0123456789abcdef"[x & 15];
1026		}
1027		tmp[40] = 0x0A;
1028		br_sslio_write_all(&ioc, tmp, 41);
1029		br_sslio_flush(&ioc);
1030	}
1031
1032twrch_loop_finished:
1033	if (br_ssl_engine_current_state(&cc.eng) == BR_SSL_CLOSED) {
1034		int err;
1035
1036		err = br_ssl_engine_last_error(&cc.eng);
1037		if (err == 0) {
1038			retcode = 0;
1039		} else {
1040			if (verbose) {
1041				print_error(err);
1042			}
1043			retcode = 1;
1044		}
1045	} else {
1046		if (verbose) {
1047			fprintf(stderr, "Engine not closed!\n");
1048		}
1049		retcode = 1;
1050	}
1051
1052	/*
1053	 * Release allocated structures.
1054	 */
1055twrch_exit:
1056	xfree(suites);
1057	xfree(suite_ids);
1058	free_certificates(chain, chain_len);
1059	free_private_key(sk);
1060	VEC_CLEAREXT(anchors, &free_ta_contents);
1061	VEC_CLEAREXT(alpn_names, &free_alpn);
1062	xfree(iobuf);
1063	xfree(cache);
1064	return retcode;
1065
1066twrch_exit_error:
1067	retcode = -1;
1068	goto twrch_exit;
1069}
1070