xref: /openbsd/lib/libcrypto/ui/ui_openssl.c (revision cedac418)
1 /* $OpenBSD: ui_openssl.c,v 1.28 2023/02/16 08:38:17 tb Exp $ */
2 /* Written by Richard Levitte (richard@levitte.org) and others
3  * for the OpenSSL project 2001.
4  */
5 /* ====================================================================
6  * Copyright (c) 2001 The OpenSSL Project.  All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  *
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  *
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in
17  *    the documentation and/or other materials provided with the
18  *    distribution.
19  *
20  * 3. All advertising materials mentioning features or use of this
21  *    software must display the following acknowledgment:
22  *    "This product includes software developed by the OpenSSL Project
23  *    for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
24  *
25  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
26  *    endorse or promote products derived from this software without
27  *    prior written permission. For written permission, please contact
28  *    openssl-core@openssl.org.
29  *
30  * 5. Products derived from this software may not be called "OpenSSL"
31  *    nor may "OpenSSL" appear in their names without prior written
32  *    permission of the OpenSSL Project.
33  *
34  * 6. Redistributions of any form whatsoever must retain the following
35  *    acknowledgment:
36  *    "This product includes software developed by the OpenSSL Project
37  *    for use in the OpenSSL Toolkit (http://www.openssl.org/)"
38  *
39  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
40  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
41  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
42  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
43  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
44  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
45  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
46  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
47  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
48  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
49  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
50  * OF THE POSSIBILITY OF SUCH DAMAGE.
51  * ====================================================================
52  *
53  * This product includes cryptographic software written by Eric Young
54  * (eay@cryptsoft.com).  This product includes software written by Tim
55  * Hudson (tjh@cryptsoft.com).
56  *
57  */
58 
59 /* The lowest level part of this file was previously in crypto/des/read_pwd.c,
60  * Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
61  * All rights reserved.
62  *
63  * This package is an SSL implementation written
64  * by Eric Young (eay@cryptsoft.com).
65  * The implementation was written so as to conform with Netscapes SSL.
66  *
67  * This library is free for commercial and non-commercial use as long as
68  * the following conditions are aheared to.  The following conditions
69  * apply to all code found in this distribution, be it the RC4, RSA,
70  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
71  * included with this distribution is covered by the same copyright terms
72  * except that the holder is Tim Hudson (tjh@cryptsoft.com).
73  *
74  * Copyright remains Eric Young's, and as such any Copyright notices in
75  * the code are not to be removed.
76  * If this package is used in a product, Eric Young should be given attribution
77  * as the author of the parts of the library used.
78  * This can be in the form of a textual message at program startup or
79  * in documentation (online or textual) provided with the package.
80  *
81  * Redistribution and use in source and binary forms, with or without
82  * modification, are permitted provided that the following conditions
83  * are met:
84  * 1. Redistributions of source code must retain the copyright
85  *    notice, this list of conditions and the following disclaimer.
86  * 2. Redistributions in binary form must reproduce the above copyright
87  *    notice, this list of conditions and the following disclaimer in the
88  *    documentation and/or other materials provided with the distribution.
89  * 3. All advertising materials mentioning features or use of this software
90  *    must display the following acknowledgement:
91  *    "This product includes cryptographic software written by
92  *     Eric Young (eay@cryptsoft.com)"
93  *    The word 'cryptographic' can be left out if the rouines from the library
94  *    being used are not cryptographic related :-).
95  * 4. If you include any Windows specific code (or a derivative thereof) from
96  *    the apps directory (application code) you must include an acknowledgement:
97  *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
98  *
99  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
100  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
101  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
102  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
103  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
104  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
105  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
106  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
107  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
108  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
109  * SUCH DAMAGE.
110  *
111  * The licence and distribution terms for any publically available version or
112  * derivative of this code cannot be changed.  i.e. this code cannot simply be
113  * copied and put under another distribution licence
114  * [including the GNU Public Licence.]
115  */
116 
117 #include <sys/ioctl.h>
118 
119 #include <openssl/opensslconf.h>
120 
121 #include <errno.h>
122 #include <signal.h>
123 #include <stdio.h>
124 #include <string.h>
125 #include <termios.h>
126 #include <unistd.h>
127 
128 #include "ui_local.h"
129 
130 #ifndef NX509_SIG
131 #define NX509_SIG 32
132 #endif
133 
134 /* Define globals.  They are protected by a lock */
135 static struct sigaction savsig[NX509_SIG];
136 
137 static struct termios tty_orig;
138 static FILE *tty_in, *tty_out;
139 static int is_a_tty;
140 
141 /* Declare static functions */
142 static int read_till_nl(FILE *);
143 static void recsig(int);
144 static void pushsig(void);
145 static void popsig(void);
146 static int read_string_inner(UI *ui, UI_STRING *uis, int echo, int strip_nl);
147 
148 static int read_string(UI *ui, UI_STRING *uis);
149 static int write_string(UI *ui, UI_STRING *uis);
150 
151 static int open_console(UI *ui);
152 static int echo_console(UI *ui);
153 static int noecho_console(UI *ui);
154 static int close_console(UI *ui);
155 
156 static UI_METHOD ui_openssl = {
157 	.name = "OpenSSL default user interface",
158 	.ui_open_session = open_console,
159 	.ui_write_string = write_string,
160 	.ui_read_string = read_string,
161 	.ui_close_session = close_console,
162 };
163 
164 /* The method with all the built-in thingies */
165 UI_METHOD *
UI_OpenSSL(void)166 UI_OpenSSL(void)
167 {
168 	return &ui_openssl;
169 }
170 LCRYPTO_ALIAS(UI_OpenSSL);
171 
172 /* The following function makes sure that info and error strings are printed
173    before any prompt. */
174 static int
write_string(UI * ui,UI_STRING * uis)175 write_string(UI *ui, UI_STRING *uis)
176 {
177 	switch (UI_get_string_type(uis)) {
178 	case UIT_ERROR:
179 	case UIT_INFO:
180 		fputs(UI_get0_output_string(uis), tty_out);
181 		fflush(tty_out);
182 		break;
183 	default:
184 		break;
185 	}
186 	return 1;
187 }
188 
189 static int
read_string(UI * ui,UI_STRING * uis)190 read_string(UI *ui, UI_STRING *uis)
191 {
192 	int ok = 0;
193 
194 	switch (UI_get_string_type(uis)) {
195 	case UIT_BOOLEAN:
196 		fputs(UI_get0_output_string(uis), tty_out);
197 		fputs(UI_get0_action_string(uis), tty_out);
198 		fflush(tty_out);
199 		return read_string_inner(ui, uis,
200 		    UI_get_input_flags(uis) & UI_INPUT_FLAG_ECHO, 0);
201 	case UIT_PROMPT:
202 		fputs(UI_get0_output_string(uis), tty_out);
203 		fflush(tty_out);
204 		return read_string_inner(ui, uis,
205 		    UI_get_input_flags(uis) & UI_INPUT_FLAG_ECHO, 1);
206 	case UIT_VERIFY:
207 		fprintf(tty_out, "Verifying - %s",
208 		    UI_get0_output_string(uis));
209 		fflush(tty_out);
210 		if ((ok = read_string_inner(ui, uis, UI_get_input_flags(uis) &
211 		    UI_INPUT_FLAG_ECHO, 1)) <= 0)
212 			return ok;
213 		if (strcmp(UI_get0_result_string(uis),
214 		    UI_get0_test_string(uis)) != 0) {
215 			fprintf(tty_out, "Verify failure\n");
216 			fflush(tty_out);
217 			return 0;
218 		}
219 		break;
220 	default:
221 		break;
222 	}
223 	return 1;
224 }
225 
226 
227 /* Internal functions to read a string without echoing */
228 static int
read_till_nl(FILE * in)229 read_till_nl(FILE *in)
230 {
231 #define SIZE 4
232 	char buf[SIZE + 1];
233 
234 	do {
235 		if (!fgets(buf, SIZE, in))
236 			return 0;
237 	} while (strchr(buf, '\n') == NULL);
238 	return 1;
239 }
240 
241 static volatile sig_atomic_t intr_signal;
242 
243 static int
read_string_inner(UI * ui,UI_STRING * uis,int echo,int strip_nl)244 read_string_inner(UI *ui, UI_STRING *uis, int echo, int strip_nl)
245 {
246 	static int ps;
247 	int ok;
248 	char result[BUFSIZ];
249 	int maxsize = BUFSIZ - 1;
250 	char *p;
251 
252 	intr_signal = 0;
253 	ok = 0;
254 	ps = 0;
255 
256 	pushsig();
257 	ps = 1;
258 
259 	if (!echo && !noecho_console(ui))
260 		goto error;
261 	ps = 2;
262 
263 	result[0] = '\0';
264 	p = fgets(result, maxsize, tty_in);
265 	if (!p)
266 		goto error;
267 	if (feof(tty_in))
268 		goto error;
269 	if (ferror(tty_in))
270 		goto error;
271 	if ((p = strchr(result, '\n')) != NULL) {
272 		if (strip_nl)
273 			*p = '\0';
274 	} else if (!read_till_nl(tty_in))
275 		goto error;
276 	if (UI_set_result(ui, uis, result) >= 0)
277 		ok = 1;
278 
279 error:
280 	if (intr_signal == SIGINT)
281 		ok = -1;
282 	if (!echo)
283 		fprintf(tty_out, "\n");
284 	if (ps >= 2 && !echo && !echo_console(ui))
285 		ok = 0;
286 
287 	if (ps >= 1)
288 		popsig();
289 
290 	explicit_bzero(result, BUFSIZ);
291 	return ok;
292 }
293 
294 
295 /* Internal functions to open, handle and close a channel to the console.  */
296 static int
open_console(UI * ui)297 open_console(UI *ui)
298 {
299 	CRYPTO_w_lock(CRYPTO_LOCK_UI);
300 	is_a_tty = 1;
301 
302 #define DEV_TTY "/dev/tty"
303 	if ((tty_in = fopen(DEV_TTY, "r")) == NULL)
304 		tty_in = stdin;
305 	if ((tty_out = fopen(DEV_TTY, "w")) == NULL)
306 		tty_out = stderr;
307 
308 	if (tcgetattr(fileno(tty_in), &tty_orig) == -1) {
309 		if (errno == ENOTTY)
310 			is_a_tty = 0;
311 		else
312 			/*
313 			 * Ariel Glenn ariel@columbia.edu reports that
314 			 * solaris can return EINVAL instead.  This should be
315 			 * ok
316 			 */
317 			if (errno == EINVAL)
318 				is_a_tty = 0;
319 		else
320 			return 0;
321 	}
322 
323 	return 1;
324 }
325 
326 static int
noecho_console(UI * ui)327 noecho_console(UI *ui)
328 {
329 	struct termios tty_new = tty_orig;
330 
331 	tty_new.c_lflag &= ~ECHO;
332 	if (is_a_tty && (tcsetattr(fileno(tty_in), TCSANOW, &tty_new) == -1))
333 		return 0;
334 	return 1;
335 }
336 
337 static int
echo_console(UI * ui)338 echo_console(UI *ui)
339 {
340 	if (is_a_tty && (tcsetattr(fileno(tty_in), TCSANOW, &tty_orig) == -1))
341 		return 0;
342 	return 1;
343 }
344 
345 static int
close_console(UI * ui)346 close_console(UI *ui)
347 {
348 	if (tty_in != stdin)
349 		fclose(tty_in);
350 	if (tty_out != stderr)
351 		fclose(tty_out);
352 	CRYPTO_w_unlock(CRYPTO_LOCK_UI);
353 
354 	return 1;
355 }
356 
357 
358 /* Internal functions to handle signals and act on them */
359 static void
pushsig(void)360 pushsig(void)
361 {
362 	int i;
363 	struct sigaction sa;
364 
365 	memset(&sa, 0, sizeof sa);
366 	sa.sa_handler = recsig;
367 
368 	for (i = 1; i < NX509_SIG; i++) {
369 		if (i == SIGUSR1)
370 			continue;
371 		if (i == SIGUSR2)
372 			continue;
373 		if (i == SIGKILL)	/* We can't make any action on that. */
374 			continue;
375 		sigaction(i, &sa, &savsig[i]);
376 	}
377 
378 	signal(SIGWINCH, SIG_DFL);
379 }
380 
381 static void
popsig(void)382 popsig(void)
383 {
384 	int i;
385 	for (i = 1; i < NX509_SIG; i++) {
386 		if (i == SIGUSR1)
387 			continue;
388 		if (i == SIGUSR2)
389 			continue;
390 		sigaction(i, &savsig[i], NULL);
391 	}
392 }
393 
394 static void
recsig(int i)395 recsig(int i)
396 {
397 	intr_signal = i;
398 }
399