xref: /freebsd/crypto/openssl/crypto/ui/ui_openssl.c (revision f25b8c9fb4f58cf61adb47d7570abe7caa6d385d)
1 /*
2  * Copyright 2001-2022 The OpenSSL Project Authors. All Rights Reserved.
3  *
4  * Licensed under the Apache License 2.0 (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
8  */
9 
10 #include "internal/e_os.h"
11 #include <openssl/e_os2.h>
12 #include <openssl/err.h>
13 #include <openssl/ui.h>
14 
15 #ifndef OPENSSL_NO_UI_CONSOLE
16 /*
17  * need for #define _POSIX_C_SOURCE arises whenever you pass -ansi to gcc
18  * [maybe others?], because it masks interfaces not discussed in standard,
19  * sigaction and fileno included. -pedantic would be more appropriate for the
20  * intended purposes, but we can't prevent users from adding -ansi.
21  */
22 #if defined(OPENSSL_SYS_VXWORKS)
23 #include <sys/types.h>
24 #endif
25 
26 #if !defined(_POSIX_C_SOURCE) && defined(OPENSSL_SYS_VMS)
27 #ifndef _POSIX_C_SOURCE
28 #define _POSIX_C_SOURCE 2
29 #endif
30 #endif
31 #include <signal.h>
32 #include <stdio.h>
33 #include <string.h>
34 #include <errno.h>
35 
36 #if !defined(OPENSSL_SYS_MSDOS) && !defined(OPENSSL_SYS_VMS)
37 #include <unistd.h>
38 /*
39  * If unistd.h defines _POSIX_VERSION, we conclude that we are on a POSIX
40  * system and have sigaction and termios.
41  */
42 #if defined(_POSIX_VERSION) && _POSIX_VERSION >= 199309L
43 
44 #define SIGACTION
45 #if !defined(TERMIOS) && !defined(TERMIO) && !defined(SGTTY)
46 #define TERMIOS
47 #endif
48 
49 #endif
50 #endif
51 
52 #include "ui_local.h"
53 #include "internal/cryptlib.h"
54 
55 #ifdef OPENSSL_SYS_VMS /* prototypes for sys$whatever */
56 #include <starlet.h>
57 #ifdef __DECC
58 #pragma message disable DOLLARID
59 #endif
60 #endif
61 
62 #ifdef WIN_CONSOLE_BUG
63 #include <windows.h>
64 #ifndef OPENSSL_SYS_WINCE
65 #include <wincon.h>
66 #endif
67 #endif
68 
69 /*
70  * There are 6 types of terminal interface supported, TERMIO, TERMIOS, VMS,
71  * MSDOS, WIN32 Console and SGTTY.
72  *
73  * If someone defines one of the macros TERMIO, TERMIOS or SGTTY, it will
74  * remain respected.  Otherwise, we default to TERMIOS except for a few
75  * systems that require something different.
76  *
77  * Note: we do not use SGTTY unless it's defined by the configuration.  We
78  * may eventually opt to remove its use entirely.
79  */
80 
81 #if !defined(TERMIOS) && !defined(TERMIO) && !defined(SGTTY)
82 
83 #if defined(_LIBC)
84 #undef TERMIOS
85 #define TERMIO
86 #undef SGTTY
87 /*
88  * We know that VMS, MSDOS, VXWORKS, use entirely other mechanisms.
89  */
90 #elif !defined(OPENSSL_SYS_VMS)    \
91     && !defined(OPENSSL_SYS_MSDOS) \
92     && !defined(OPENSSL_SYS_VXWORKS)
93 #define TERMIOS
94 #undef TERMIO
95 #undef SGTTY
96 #endif
97 
98 #endif
99 
100 #if defined(OPENSSL_SYS_VXWORKS)
101 #undef TERMIOS
102 #undef TERMIO
103 #undef SGTTY
104 #endif
105 
106 #ifdef TERMIOS
107 #include <termios.h>
108 #define TTY_STRUCT struct termios
109 #define TTY_FLAGS c_lflag
110 #define TTY_get(tty, data) tcgetattr(tty, data)
111 #define TTY_set(tty, data) tcsetattr(tty, TCSANOW, data)
112 #endif
113 
114 #ifdef TERMIO
115 #include <termio.h>
116 #define TTY_STRUCT struct termio
117 #define TTY_FLAGS c_lflag
118 #define TTY_get(tty, data) ioctl(tty, TCGETA, data)
119 #define TTY_set(tty, data) ioctl(tty, TCSETA, data)
120 #endif
121 
122 #ifdef SGTTY
123 #include <sgtty.h>
124 #define TTY_STRUCT struct sgttyb
125 #define TTY_FLAGS sg_flags
126 #define TTY_get(tty, data) ioctl(tty, TIOCGETP, data)
127 #define TTY_set(tty, data) ioctl(tty, TIOCSETP, data)
128 #endif
129 
130 #if !defined(_LIBC) && !defined(OPENSSL_SYS_MSDOS) && !defined(OPENSSL_SYS_VMS) && !(defined(OPENSSL_SYS_TANDEM) && defined(_SPT_MODEL_))
131 #include <sys/ioctl.h>
132 #endif
133 
134 #ifdef OPENSSL_SYS_MSDOS
135 #include <conio.h>
136 #endif
137 
138 #ifdef OPENSSL_SYS_VMS
139 #include <ssdef.h>
140 #include <iodef.h>
141 #include <ttdef.h>
142 #include <descrip.h>
143 struct IOSB {
144     short iosb$w_value;
145     short iosb$w_count;
146     long iosb$l_info;
147 };
148 #endif
149 
150 #ifndef NX509_SIG
151 #define NX509_SIG 32
152 #endif
153 
154 /* Define globals.  They are protected by a lock */
155 #ifdef SIGACTION
156 static struct sigaction savsig[NX509_SIG];
157 #else
158 static void (*savsig[NX509_SIG])(int);
159 #endif
160 
161 #ifdef OPENSSL_SYS_VMS
162 static struct IOSB iosb;
163 static $DESCRIPTOR(terminal, "TT");
164 static long tty_orig[3], tty_new[3]; /* XXX Is there any guarantee that this
165                                       * will always suffice for the actual
166                                       * structures? */
167 static long status;
168 static unsigned short channel = 0;
169 #elif defined(_WIN32) && !defined(_WIN32_WCE)
170 static DWORD tty_orig, tty_new;
171 #else
172 #if !defined(OPENSSL_SYS_MSDOS) || defined(__DJGPP__)
173 static TTY_STRUCT tty_orig, tty_new;
174 #endif
175 #endif
176 static FILE *tty_in, *tty_out;
177 static int is_a_tty;
178 
179 /* Declare static functions */
180 #if !defined(OPENSSL_SYS_WINCE)
181 static int read_till_nl(FILE *);
182 static void recsig(int);
183 static void pushsig(void);
184 static void popsig(void);
185 #endif
186 #if defined(OPENSSL_SYS_MSDOS) && !defined(_WIN32)
187 static int noecho_fgets(char *buf, int size, FILE *tty);
188 #endif
189 static int read_string_inner(UI *ui, UI_STRING *uis, int echo, int strip_nl);
190 
191 static int read_string(UI *ui, UI_STRING *uis);
192 static int write_string(UI *ui, UI_STRING *uis);
193 
194 static int open_console(UI *ui);
195 static int echo_console(UI *ui);
196 static int noecho_console(UI *ui);
197 static int close_console(UI *ui);
198 
199 /*
200  * The following function makes sure that info and error strings are printed
201  * before any prompt.
202  */
203 static int write_string(UI *ui, UI_STRING *uis)
204 {
205     switch (UI_get_string_type(uis)) {
206     case UIT_ERROR:
207     case UIT_INFO:
208         fputs(UI_get0_output_string(uis), tty_out);
209         fflush(tty_out);
210         break;
211     case UIT_NONE:
212     case UIT_PROMPT:
213     case UIT_VERIFY:
214     case UIT_BOOLEAN:
215         break;
216     }
217     return 1;
218 }
219 
220 static int read_string(UI *ui, UI_STRING *uis)
221 {
222     int ok = 0;
223 
224     switch (UI_get_string_type(uis)) {
225     case UIT_BOOLEAN:
226         fputs(UI_get0_output_string(uis), tty_out);
227         fputs(UI_get0_action_string(uis), tty_out);
228         fflush(tty_out);
229         return read_string_inner(ui, uis,
230             UI_get_input_flags(uis) & UI_INPUT_FLAG_ECHO,
231             0);
232     case UIT_PROMPT:
233         fputs(UI_get0_output_string(uis), tty_out);
234         fflush(tty_out);
235         return read_string_inner(ui, uis,
236             UI_get_input_flags(uis) & UI_INPUT_FLAG_ECHO,
237             1);
238     case UIT_VERIFY:
239         fprintf(tty_out, "Verifying - %s", UI_get0_output_string(uis));
240         fflush(tty_out);
241         if ((ok = read_string_inner(ui, uis,
242                  UI_get_input_flags(uis) & UI_INPUT_FLAG_ECHO, 1))
243             <= 0)
244             return ok;
245         if (strcmp(UI_get0_result_string(uis), UI_get0_test_string(uis)) != 0) {
246             fprintf(tty_out, "Verify failure\n");
247             fflush(tty_out);
248             return 0;
249         }
250         break;
251     case UIT_NONE:
252     case UIT_INFO:
253     case UIT_ERROR:
254         break;
255     }
256     return 1;
257 }
258 
259 #if !defined(OPENSSL_SYS_WINCE)
260 /* Internal functions to read a string without echoing */
261 static int read_till_nl(FILE *in)
262 {
263 #define SIZE 4
264     char buf[SIZE + 1];
265 
266     do {
267         if (!fgets(buf, SIZE, in))
268             return 0;
269     } while (strchr(buf, '\n') == NULL);
270     return 1;
271 }
272 
273 static volatile sig_atomic_t intr_signal;
274 #endif
275 
276 static int read_string_inner(UI *ui, UI_STRING *uis, int echo, int strip_nl)
277 {
278     static int ps;
279     int ok;
280     char result[BUFSIZ];
281     int maxsize = BUFSIZ - 1;
282 #if !defined(OPENSSL_SYS_WINCE)
283     char *p = NULL;
284     int echo_eol = !echo;
285 
286     intr_signal = 0;
287     ok = 0;
288     ps = 0;
289 
290     pushsig();
291     ps = 1;
292 
293     if (!echo && !noecho_console(ui))
294         goto error;
295     ps = 2;
296 
297     result[0] = '\0';
298 #if defined(_WIN32)
299     if (is_a_tty) {
300         DWORD numread;
301 #if defined(CP_UTF8)
302         if (GetEnvironmentVariableW(L"OPENSSL_WIN32_UTF8", NULL, 0) != 0) {
303             WCHAR wresult[BUFSIZ];
304 
305             if (ReadConsoleW(GetStdHandle(STD_INPUT_HANDLE),
306                     wresult, maxsize, &numread, NULL)) {
307                 if (numread >= 2 && wresult[numread - 2] == L'\r' && wresult[numread - 1] == L'\n') {
308                     wresult[numread - 2] = L'\n';
309                     numread--;
310                 }
311                 wresult[numread] = '\0';
312                 if (WideCharToMultiByte(CP_UTF8, 0, wresult, -1,
313                         result, sizeof(result), NULL, 0)
314                     > 0)
315                     p = result;
316 
317                 OPENSSL_cleanse(wresult, sizeof(wresult));
318             }
319         } else
320 #endif
321             if (ReadConsoleA(GetStdHandle(STD_INPUT_HANDLE),
322                     result, maxsize, &numread, NULL)) {
323             if (numread >= 2 && result[numread - 2] == '\r' && result[numread - 1] == '\n') {
324                 result[numread - 2] = '\n';
325                 numread--;
326             }
327             result[numread] = '\0';
328             p = result;
329         }
330     } else
331 #elif defined(OPENSSL_SYS_MSDOS)
332     if (!echo) {
333         noecho_fgets(result, maxsize, tty_in);
334         p = result; /* FIXME: noecho_fgets doesn't return errors */
335     } else
336 #endif
337         p = fgets(result, maxsize, tty_in);
338     if (p == NULL)
339         goto error;
340     if (feof(tty_in))
341         goto error;
342     if (ferror(tty_in))
343         goto error;
344     if ((p = (char *)strchr(result, '\n')) != NULL) {
345         if (strip_nl)
346             *p = '\0';
347     } else if (!read_till_nl(tty_in))
348         goto error;
349     if (UI_set_result(ui, uis, result) >= 0)
350         ok = 1;
351 
352 error:
353     if (intr_signal == SIGINT)
354         ok = -1;
355     if (echo_eol)
356         fprintf(tty_out, "\n");
357     if (ps >= 2 && !echo && !echo_console(ui))
358         ok = 0;
359 
360     if (ps >= 1)
361         popsig();
362 #else
363     ok = 1;
364 #endif
365 
366     OPENSSL_cleanse(result, BUFSIZ);
367     return ok;
368 }
369 
370 /* Internal functions to open, handle and close a channel to the console.  */
371 static int open_console(UI *ui)
372 {
373     if (!CRYPTO_THREAD_write_lock(ui->lock))
374         return 0;
375     is_a_tty = 1;
376 
377 #if defined(OPENSSL_SYS_VXWORKS)
378     tty_in = stdin;
379     tty_out = stderr;
380 #elif defined(_WIN32) && !defined(_WIN32_WCE)
381     if ((tty_out = fopen("conout$", "w")) == NULL)
382         tty_out = stderr;
383 
384     if (GetConsoleMode(GetStdHandle(STD_INPUT_HANDLE), &tty_orig)) {
385         tty_in = stdin;
386     } else {
387         is_a_tty = 0;
388         if ((tty_in = fopen("conin$", "r")) == NULL)
389             tty_in = stdin;
390     }
391 #else
392 #ifdef OPENSSL_SYS_MSDOS
393 #define DEV_TTY "con"
394 #else
395 #define DEV_TTY "/dev/tty"
396 #endif
397     if ((tty_in = fopen(DEV_TTY, "r")) == NULL)
398         tty_in = stdin;
399     if ((tty_out = fopen(DEV_TTY, "w")) == NULL)
400         tty_out = stderr;
401 #endif
402 
403 #if defined(TTY_get) && !defined(OPENSSL_SYS_VMS)
404     if (TTY_get(fileno(tty_in), &tty_orig) == -1) {
405 #ifdef ENOTTY
406         if (errno == ENOTTY)
407             is_a_tty = 0;
408         else
409 #endif
410 #ifdef EINVAL
411             /*
412              * Ariel Glenn reports that solaris can return EINVAL instead.
413              * This should be ok
414              */
415             if (errno == EINVAL)
416                 is_a_tty = 0;
417             else
418 #endif
419 #ifdef ENXIO
420                 /*
421                  * Solaris can return ENXIO.
422                  * This should be ok
423                  */
424                 if (errno == ENXIO)
425                     is_a_tty = 0;
426                 else
427 #endif
428 #ifdef EIO
429                     /*
430                      * Linux can return EIO.
431                      * This should be ok
432                      */
433                     if (errno == EIO)
434                         is_a_tty = 0;
435                     else
436 #endif
437 #ifdef EPERM
438                         /*
439                          * Linux can return EPERM (Operation not permitted),
440                          * e.g. if a daemon executes openssl via fork()+execve()
441                          * This should be ok
442                          */
443                         if (errno == EPERM)
444                             is_a_tty = 0;
445                         else
446 #endif
447 #ifdef ENODEV
448                             /*
449                              * MacOS X returns ENODEV (Operation not supported by device),
450                              * which seems appropriate.
451                              */
452                             if (errno == ENODEV)
453                                 is_a_tty = 0;
454                             else
455 #endif
456                             {
457                                 ERR_raise_data(ERR_LIB_UI, UI_R_UNKNOWN_TTYGET_ERRNO_VALUE,
458                                     "errno=%d", errno);
459                                 return 0;
460                             }
461     }
462 #endif
463 #ifdef OPENSSL_SYS_VMS
464     status = sys$assign(&terminal, &channel, 0, 0);
465 
466     /* if there isn't a TT device, something is very wrong */
467     if (status != SS$_NORMAL) {
468         ERR_raise_data(ERR_LIB_UI, UI_R_SYSASSIGN_ERROR,
469             "status=%%X%08X", status);
470         return 0;
471     }
472 
473     status = sys$qiow(0, channel, IO$_SENSEMODE, &iosb, 0, 0, tty_orig, 12,
474         0, 0, 0, 0);
475 
476     /* If IO$_SENSEMODE doesn't work, this is not a terminal device */
477     if ((status != SS$_NORMAL) || (iosb.iosb$w_value != SS$_NORMAL))
478         is_a_tty = 0;
479 #endif
480     return 1;
481 }
482 
483 static int noecho_console(UI *ui)
484 {
485 #ifdef TTY_FLAGS
486     memcpy(&(tty_new), &(tty_orig), sizeof(tty_orig));
487     tty_new.TTY_FLAGS &= ~ECHO;
488 #endif
489 
490 #if defined(TTY_set) && !defined(OPENSSL_SYS_VMS)
491     if (is_a_tty && (TTY_set(fileno(tty_in), &tty_new) == -1))
492         return 0;
493 #endif
494 #ifdef OPENSSL_SYS_VMS
495     if (is_a_tty) {
496         tty_new[0] = tty_orig[0];
497         tty_new[1] = tty_orig[1] | TT$M_NOECHO;
498         tty_new[2] = tty_orig[2];
499         status = sys$qiow(0, channel, IO$_SETMODE, &iosb, 0, 0, tty_new, 12,
500             0, 0, 0, 0);
501         if ((status != SS$_NORMAL) || (iosb.iosb$w_value != SS$_NORMAL)) {
502             ERR_raise_data(ERR_LIB_UI, UI_R_SYSQIOW_ERROR,
503                 "status=%%X%08X, iosb.iosb$w_value=%%X%08X",
504                 status, iosb.iosb$w_value);
505             return 0;
506         }
507     }
508 #endif
509 #if defined(_WIN32) && !defined(_WIN32_WCE)
510     if (is_a_tty) {
511         tty_new = tty_orig;
512         tty_new &= ~ENABLE_ECHO_INPUT;
513         SetConsoleMode(GetStdHandle(STD_INPUT_HANDLE), tty_new);
514     }
515 #endif
516     return 1;
517 }
518 
519 static int echo_console(UI *ui)
520 {
521 #if defined(TTY_set) && !defined(OPENSSL_SYS_VMS)
522     memcpy(&(tty_new), &(tty_orig), sizeof(tty_orig));
523     if (is_a_tty && (TTY_set(fileno(tty_in), &tty_new) == -1))
524         return 0;
525 #endif
526 #ifdef OPENSSL_SYS_VMS
527     if (is_a_tty) {
528         tty_new[0] = tty_orig[0];
529         tty_new[1] = tty_orig[1];
530         tty_new[2] = tty_orig[2];
531         status = sys$qiow(0, channel, IO$_SETMODE, &iosb, 0, 0, tty_new, 12,
532             0, 0, 0, 0);
533         if ((status != SS$_NORMAL) || (iosb.iosb$w_value != SS$_NORMAL)) {
534             ERR_raise_data(ERR_LIB_UI, UI_R_SYSQIOW_ERROR,
535                 "status=%%X%08X, iosb.iosb$w_value=%%X%08X",
536                 status, iosb.iosb$w_value);
537             return 0;
538         }
539     }
540 #endif
541 #if defined(_WIN32) && !defined(_WIN32_WCE)
542     if (is_a_tty) {
543         tty_new = tty_orig;
544         SetConsoleMode(GetStdHandle(STD_INPUT_HANDLE), tty_new);
545     }
546 #endif
547     return 1;
548 }
549 
550 static int close_console(UI *ui)
551 {
552     int ret = 1;
553 
554     if (tty_in != stdin)
555         fclose(tty_in);
556     if (tty_out != stderr)
557         fclose(tty_out);
558 #ifdef OPENSSL_SYS_VMS
559     status = sys$dassgn(channel);
560     if (status != SS$_NORMAL) {
561         ERR_raise_data(ERR_LIB_UI, UI_R_SYSDASSGN_ERROR,
562             "status=%%X%08X", status);
563         ret = 0;
564     }
565 #endif
566     CRYPTO_THREAD_unlock(ui->lock);
567 
568     return ret;
569 }
570 
571 #if !defined(OPENSSL_SYS_WINCE)
572 /* Internal functions to handle signals and act on them */
573 static void pushsig(void)
574 {
575 #ifndef OPENSSL_SYS_WIN32
576     int i;
577 #endif
578 #ifdef SIGACTION
579     struct sigaction sa;
580 
581     memset(&sa, 0, sizeof(sa));
582     sa.sa_handler = recsig;
583 #endif
584 
585 #ifdef OPENSSL_SYS_WIN32
586     savsig[SIGABRT] = signal(SIGABRT, recsig);
587     savsig[SIGFPE] = signal(SIGFPE, recsig);
588     savsig[SIGILL] = signal(SIGILL, recsig);
589     savsig[SIGINT] = signal(SIGINT, recsig);
590     savsig[SIGSEGV] = signal(SIGSEGV, recsig);
591     savsig[SIGTERM] = signal(SIGTERM, recsig);
592 #else
593     for (i = 1; i < NX509_SIG; i++) {
594 #ifdef SIGUSR1
595         if (i == SIGUSR1)
596             continue;
597 #endif
598 #ifdef SIGUSR2
599         if (i == SIGUSR2)
600             continue;
601 #endif
602 #ifdef SIGKILL
603         if (i == SIGKILL) /* We can't make any action on that. */
604             continue;
605 #endif
606 #ifdef SIGACTION
607         sigaction(i, &sa, &savsig[i]);
608 #else
609         savsig[i] = signal(i, recsig);
610 #endif
611     }
612 #endif
613 
614 #ifdef SIGWINCH
615     signal(SIGWINCH, SIG_DFL);
616 #endif
617 }
618 
619 static void popsig(void)
620 {
621 #ifdef OPENSSL_SYS_WIN32
622     signal(SIGABRT, savsig[SIGABRT]);
623     signal(SIGFPE, savsig[SIGFPE]);
624     signal(SIGILL, savsig[SIGILL]);
625     signal(SIGINT, savsig[SIGINT]);
626     signal(SIGSEGV, savsig[SIGSEGV]);
627     signal(SIGTERM, savsig[SIGTERM]);
628 #else
629     int i;
630     for (i = 1; i < NX509_SIG; i++) {
631 #ifdef SIGUSR1
632         if (i == SIGUSR1)
633             continue;
634 #endif
635 #ifdef SIGUSR2
636         if (i == SIGUSR2)
637             continue;
638 #endif
639 #ifdef SIGACTION
640         sigaction(i, &savsig[i], NULL);
641 #else
642         signal(i, savsig[i]);
643 #endif
644     }
645 #endif
646 }
647 
648 static void recsig(int i)
649 {
650     intr_signal = i;
651 }
652 #endif
653 
654 /* Internal functions specific for Windows */
655 #if defined(OPENSSL_SYS_MSDOS) && !defined(_WIN32)
656 static int noecho_fgets(char *buf, int size, FILE *tty)
657 {
658     int i;
659     char *p;
660 
661     p = buf;
662     for (;;) {
663         if (size == 0) {
664             *p = '\0';
665             break;
666         }
667         size--;
668 #if defined(_WIN32)
669         i = _getch();
670 #else
671         i = getch();
672 #endif
673         if (i == '\r')
674             i = '\n';
675         *(p++) = i;
676         if (i == '\n') {
677             *p = '\0';
678             break;
679         }
680     }
681 #ifdef WIN_CONSOLE_BUG
682     /*
683      * Win95 has several evil console bugs: one of these is that the last
684      * character read using getch() is passed to the next read: this is
685      * usually a CR so this can be trouble. No STDIO fix seems to work but
686      * flushing the console appears to do the trick.
687      */
688     {
689         HANDLE inh;
690         inh = GetStdHandle(STD_INPUT_HANDLE);
691         FlushConsoleInputBuffer(inh);
692     }
693 #endif
694     return strlen(buf);
695 }
696 #endif
697 
698 static UI_METHOD ui_openssl = {
699     "OpenSSL default user interface",
700     open_console,
701     write_string,
702     NULL, /* No flusher is needed for command lines */
703     read_string,
704     close_console,
705     NULL
706 };
707 
708 /* The method with all the built-in console thingies */
709 UI_METHOD *UI_OpenSSL(void)
710 {
711     return &ui_openssl;
712 }
713 
714 static const UI_METHOD *default_UI_meth = &ui_openssl;
715 
716 #else
717 
718 static const UI_METHOD *default_UI_meth = NULL;
719 
720 #endif
721 
722 void UI_set_default_method(const UI_METHOD *meth)
723 {
724     default_UI_meth = meth;
725 }
726 
727 const UI_METHOD *UI_get_default_method(void)
728 {
729     return default_UI_meth;
730 }
731