crypto/ui/ui_openssl.c

   1 /*
   2  * Copyright 2001-2020 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 "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) &
 243                                     UI_INPUT_FLAG_ECHO, 1)) <= 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 &&
 308                     wresult[numread-2] == L'\r' &&
 309                     wresult[numread-1] == L'\n') {
 310                     wresult[numread-2] = L'\n';
 311                     numread--;
 312                 }
 313                 wresult[numread] = '\0';
 314                 if (WideCharToMultiByte(CP_UTF8, 0, wresult, -1,
 315                                         result, sizeof(result), NULL, 0) > 0)
 316                     p = result;
 317
 318                 OPENSSL_cleanse(wresult, sizeof(wresult));
 319             }
 320         } else
 321 #   endif
 322         if (ReadConsoleA(GetStdHandle(STD_INPUT_HANDLE),
 323                          result, maxsize, &numread, NULL)) {
 324             if (numread >= 2 &&
 325                 result[numread-2] == '\r' && result[numread-1] == '\n') {
 326                 result[numread-2] = '\n';
 327                 numread--;
 328             }
 329             result[numread] = '\0';
 330             p = result;
 331         }
 332     } else
 333 #  elif defined(OPENSSL_SYS_MSDOS)
 334     if (!echo) {
 335         noecho_fgets(result, maxsize, tty_in);
 336         p = result;             /* FIXME: noecho_fgets doesn't return errors */
 337     } else
 338 #  endif
 339     p = fgets(result, maxsize, tty_in);
 340     if (p == NULL)
 341         goto error;
 342     if (feof(tty_in))
 343         goto error;
 344     if (ferror(tty_in))
 345         goto error;
 346     if ((p = (char *)strchr(result, '\n')) != NULL) {
 347         if (strip_nl)
 348             *p = '\0';
 349     } else if (!read_till_nl(tty_in))
 350         goto error;
 351     if (UI_set_result(ui, uis, result) >= 0)
 352         ok = 1;
 353
 354  error:
 355     if (intr_signal == SIGINT)
 356         ok = -1;
 357     if (echo_eol)
 358         fprintf(tty_out, "\n");
 359     if (ps >= 2 && !echo && !echo_console(ui))
 360         ok = 0;
 361
 362     if (ps >= 1)
 363         popsig();
 364 # else
 365     ok = 1;
 366 # endif
 367
 368     OPENSSL_cleanse(result, BUFSIZ);
 369     return ok;
 370 }
 371
 372 /* Internal functions to open, handle and close a channel to the console.  */
 373 static int open_console(UI *ui)
 374 {
 375     if (!CRYPTO_THREAD_write_lock(ui->lock))
 376         return 0;
 377     is_a_tty = 1;
 378
 379 # if defined(OPENSSL_SYS_VXWORKS)
 380     tty_in = stdin;
 381     tty_out = stderr;
 382 # elif defined(_WIN32) && !defined(_WIN32_WCE)
 383     if ((tty_out = fopen("conout$", "w")) == NULL)
 384         tty_out = stderr;
 385
 386     if (GetConsoleMode(GetStdHandle(STD_INPUT_HANDLE), &tty_orig)) {
 387         tty_in = stdin;
 388     } else {
 389         is_a_tty = 0;
 390         if ((tty_in = fopen("conin$", "r")) == NULL)
 391             tty_in = stdin;
 392     }
 393 # else
 394 #  ifdef OPENSSL_SYS_MSDOS
 395 #   define DEV_TTY "con"
 396 #  else
 397 #   define DEV_TTY "/dev/tty"
 398 #  endif
 399     if ((tty_in = fopen(DEV_TTY, "r")) == NULL)
 400         tty_in = stdin;
 401     if ((tty_out = fopen(DEV_TTY, "w")) == NULL)
 402         tty_out = stderr;
 403 # endif
 404
 405 # if defined(TTY_get) && !defined(OPENSSL_SYS_VMS)
 406     if (TTY_get(fileno(tty_in), &tty_orig) == -1) {
 407 #  ifdef ENOTTY
 408         if (errno == ENOTTY)
 409             is_a_tty = 0;
 410         else
 411 #  endif
 412 #  ifdef EINVAL
 413             /*
 414              * Ariel Glenn reports that solaris can return EINVAL instead.
 415              * This should be ok
 416              */
 417         if (errno == EINVAL)
 418             is_a_tty = 0;
 419         else
 420 #  endif
 421 #  ifdef ENXIO
 422             /*
 423              * Solaris can return ENXIO.
 424              * This should be ok
 425              */
 426         if (errno == ENXIO)
 427             is_a_tty = 0;
 428         else
 429 #  endif
 430 #  ifdef EIO
 431             /*
 432              * Linux can return EIO.
 433              * This should be ok
 434              */
 435         if (errno == EIO)
 436             is_a_tty = 0;
 437         else
 438 #  endif
 439 #  ifdef EPERM
 440             /*
 441              * Linux can return EPERM (Operation not permitted),
 442              * e.g. if a daemon executes openssl via fork()+execve()
 443              * This should be ok
 444              */
 445         if (errno == EPERM)
 446             is_a_tty = 0;
 447         else
 448 #  endif
 449 #  ifdef ENODEV
 450             /*
 451              * MacOS X returns ENODEV (Operation not supported by device),
 452              * which seems appropriate.
 453              */
 454         if (errno == ENODEV)
 455                 is_a_tty = 0;
 456         else
 457 #  endif
 458             {
 459                 ERR_raise_data(ERR_LIB_UI, UI_R_UNKNOWN_TTYGET_ERRNO_VALUE,
 460                                "errno=%d", errno);
 461                 return 0;
 462             }
 463     }
 464 # endif
 465 # ifdef OPENSSL_SYS_VMS
 466     status = sys$assign(&terminal, &channel, 0, 0);
 467
 468     /* if there isn't a TT device, something is very wrong */
 469     if (status != SS$_NORMAL) {
 470         ERR_raise_data(ERR_LIB_UI, UI_R_SYSASSIGN_ERROR,
 471                        "status=%%X%08X", status);
 472         return 0;
 473     }
 474
 475     status = sys$qiow(0, channel, IO$_SENSEMODE, &iosb, 0, 0, tty_orig, 12,
 476                       0, 0, 0, 0);
 477
 478     /* If IO$_SENSEMODE doesn't work, this is not a terminal device */
 479     if ((status != SS$_NORMAL) || (iosb.iosb$w_value != SS$_NORMAL))
 480         is_a_tty = 0;
 481 # endif
 482     return 1;
 483 }
 484
 485 static int noecho_console(UI *ui)
 486 {
 487 # ifdef TTY_FLAGS
 488     memcpy(&(tty_new), &(tty_orig), sizeof(tty_orig));
 489     tty_new.TTY_FLAGS &= ~ECHO;
 490 # endif
 491
 492 # if defined(TTY_set) && !defined(OPENSSL_SYS_VMS)
 493     if (is_a_tty && (TTY_set(fileno(tty_in), &tty_new) == -1))
 494         return 0;
 495 # endif
 496 # ifdef OPENSSL_SYS_VMS
 497     if (is_a_tty) {
 498         tty_new[0] = tty_orig[0];
 499         tty_new[1] = tty_orig[1] | TT$M_NOECHO;
 500         tty_new[2] = tty_orig[2];
 501         status = sys$qiow(0, channel, IO$_SETMODE, &iosb, 0, 0, tty_new, 12,
 502                           0, 0, 0, 0);
 503         if ((status != SS$_NORMAL) || (iosb.iosb$w_value != SS$_NORMAL)) {
 504             ERR_raise_data(ERR_LIB_UI, UI_R_SYSQIOW_ERROR,
 505                            "status=%%X%08X, iosb.iosb$w_value=%%X%08X",
 506                            status, iosb.iosb$w_value);
 507             return 0;
 508         }
 509     }
 510 # endif
 511 # if defined(_WIN32) && !defined(_WIN32_WCE)
 512     if (is_a_tty) {
 513         tty_new = tty_orig;
 514         tty_new &= ~ENABLE_ECHO_INPUT;
 515         SetConsoleMode(GetStdHandle(STD_INPUT_HANDLE), tty_new);
 516     }
 517 # endif
 518     return 1;
 519 }
 520
 521 static int echo_console(UI *ui)
 522 {
 523 # if defined(TTY_set) && !defined(OPENSSL_SYS_VMS)
 524     memcpy(&(tty_new), &(tty_orig), sizeof(tty_orig));
 525     if (is_a_tty && (TTY_set(fileno(tty_in), &tty_new) == -1))
 526         return 0;
 527 # endif
 528 # ifdef OPENSSL_SYS_VMS
 529     if (is_a_tty) {
 530         tty_new[0] = tty_orig[0];
 531         tty_new[1] = tty_orig[1];
 532         tty_new[2] = tty_orig[2];
 533         status = sys$qiow(0, channel, IO$_SETMODE, &iosb, 0, 0, tty_new, 12,
 534                           0, 0, 0, 0);
 535         if ((status != SS$_NORMAL) || (iosb.iosb$w_value != SS$_NORMAL)) {
 536             ERR_raise_data(ERR_LIB_UI, UI_R_SYSQIOW_ERROR,
 537                            "status=%%X%08X, iosb.iosb$w_value=%%X%08X",
 538                            status, iosb.iosb$w_value);
 539             return 0;
 540         }
 541     }
 542 # endif
 543 # if defined(_WIN32) && !defined(_WIN32_WCE)
 544     if (is_a_tty) {
 545         tty_new = tty_orig;
 546         SetConsoleMode(GetStdHandle(STD_INPUT_HANDLE), tty_new);
 547     }
 548 # endif
 549     return 1;
 550 }
 551
 552 static int close_console(UI *ui)
 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         return 0;
 564     }
 565 # endif
 566     CRYPTO_THREAD_unlock(ui->lock);
 567
 568     return 1;
 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 }