puttygen.c

   1 /*
   2  * PuTTY key generation front end.
   3  */
   4
   5 #include <windows.h>
   6 #include <commctrl.h>
   7 #include <time.h>
   8 #ifndef NO_SECURITY
   9 #include <aclapi.h>
  10 #endif
  11 #include <stdio.h>
  12
  13 #define PUTTY_DO_GLOBALS
  14
  15 #include "putty.h"
  16 #include "ssh.h"
  17 #include "winstuff.h"
  18
  19 #define WM_DONEKEY (WM_XUSER + 1)
  20
  21 #define KEYSIZE 1024
  22
  23 /*
  24  * TODO:
  25  *  - have some means of verifying passphrase changes against typos
  26  *  - prompt before overwriting an existing file
  27  *  - check the return value from saversakey()
  28  *  - test the generated keys for actual working-RSA-key-hood
  29  *  - variable key size
  30  */
  31
  32 /* ----------------------------------------------------------------------
  33  * Progress report code. This is really horrible :-)
  34  */
  35 #define PHASE1TOTAL 0x10000
  36 #define PHASE2TOTAL 0x10000
  37 #define PHASE3TOTAL 0x04000
  38 #define PHASE1START 0
  39 #define PHASE2START (PHASE1TOTAL)
  40 #define PHASE3START (PHASE1TOTAL + PHASE2TOTAL)
  41 #define TOTALTOTAL  (PHASE1TOTAL + PHASE2TOTAL + PHASE3TOTAL)
  42 #define PROGRESSBIGRANGE 65535
  43 #define DIVISOR     ((TOTALTOTAL + PROGRESSBIGRANGE - 1) / PROGRESSBIGRANGE)
  44 #define PROGRESSRANGE (TOTALTOTAL / DIVISOR)
  45 struct progress {
  46     unsigned phase1param, phase1current, phase1n;
  47     unsigned phase2param, phase2current, phase2n;
  48     unsigned phase3mult;
  49     HWND progbar;
  50 };
  51
  52 static void progress_update(void *param, int phase, int iprogress) {
  53     struct progress *p = (struct progress *)param;
  54     unsigned progress = iprogress;
  55     int position;
  56
  57     switch (phase) {
  58       case -1:
  59         p->phase1param = 0x10000 + progress;
  60         p->phase1current = 0x10000; p->phase1n = 0;
  61         return;
  62       case -2:
  63         p->phase2param = 0x10000 + progress;
  64         p->phase2current = 0x10000; p->phase2n = 0;
  65         return;
  66       case -3:
  67         p->phase3mult = PHASE3TOTAL / progress;
  68         return;
  69       case 1:
  70         while (p->phase1n < progress) {
  71             p->phase1n++;
  72             p->phase1current *= p->phase1param;
  73             p->phase1current /= 0x10000;
  74         }
  75         position = PHASE1START + 0x10000 - p->phase1current;
  76         break;
  77       case 2:
  78         while (p->phase2n < progress) {
  79             p->phase2n++;
  80             p->phase2current *= p->phase2param;
  81             p->phase2current /= 0x10000;
  82         }
  83         position = PHASE2START + 0x10000 - p->phase2current;
  84         break;
  85       case 3:
  86         position = PHASE3START + progress * p->phase3mult;
  87         break;
  88     }
  89
  90     SendMessage(p->progbar, PBM_SETPOS, position / DIVISOR, 0);
  91 }
  92
  93 extern char ver[];
  94
  95 #define PASSPHRASE_MAXLEN 512
  96
  97 struct PassphraseProcStruct {
  98     char *passphrase;
  99     char *comment;
 100 };
 101
 102 /*
 103  * Dialog-box function for the passphrase box.
 104  */
 105 static int CALLBACK PassphraseProc(HWND hwnd, UINT msg,
 106                                    WPARAM wParam, LPARAM lParam) {
 107     static char *passphrase;
 108     struct PassphraseProcStruct *p;
 109
 110     switch (msg) {
 111       case WM_INITDIALOG:
 112         SetForegroundWindow(hwnd);
 113         SetWindowPos (hwnd, HWND_TOP, 0, 0, 0, 0,
 114                       SWP_NOMOVE | SWP_NOSIZE | SWP_SHOWWINDOW);
 115         p = (struct PassphraseProcStruct *)lParam;
 116         passphrase = p->passphrase;
 117         if (p->comment)
 118             SetDlgItemText(hwnd, 101, p->comment);
 119         *passphrase = 0;
 120         return 0;
 121       case WM_COMMAND:
 122         switch (LOWORD(wParam)) {
 123           case IDOK:
 124             if (*passphrase)
 125                 EndDialog (hwnd, 1);
 126             else
 127                 MessageBeep (0);
 128             return 0;
 129           case IDCANCEL:
 130             EndDialog (hwnd, 0);
 131             return 0;
 132           case 102:                    /* edit box */
 133             if (HIWORD(wParam) == EN_CHANGE) {
 134                 GetDlgItemText (hwnd, 102, passphrase, PASSPHRASE_MAXLEN-1);
 135                 passphrase[PASSPHRASE_MAXLEN-1] = '\0';
 136             }
 137             return 0;
 138         }
 139         return 0;
 140       case WM_CLOSE:
 141         EndDialog (hwnd, 0);
 142         return 0;
 143     }
 144     return 0;
 145 }
 146
 147 /*
 148  * Prompt for a key file. Assumes the filename buffer is of size
 149  * FILENAME_MAX.
 150  */
 151 static int prompt_keyfile(HWND hwnd, char *dlgtitle,
 152                           char *filename, int save) {
 153     OPENFILENAME of;
 154     memset(&of, 0, sizeof(of));
 155 #ifdef OPENFILENAME_SIZE_VERSION_400
 156     of.lStructSize = OPENFILENAME_SIZE_VERSION_400;
 157 #else
 158     of.lStructSize = sizeof(of);
 159 #endif
 160     of.hwndOwner = hwnd;
 161     of.lpstrFilter = "All Files\0*\0\0\0";
 162     of.lpstrCustomFilter = NULL;
 163     of.nFilterIndex = 1;
 164     of.lpstrFile = filename; *filename = '\0';
 165     of.nMaxFile = FILENAME_MAX;
 166     of.lpstrFileTitle = NULL;
 167     of.lpstrInitialDir = NULL;
 168     of.lpstrTitle = dlgtitle;
 169     of.Flags = 0;
 170     if (save)
 171         return GetSaveFileName(&of);
 172     else
 173         return GetOpenFileName(&of);
 174 }
 175
 176 /*
 177  * This function is needed to link with the DES code. We need not
 178  * have it do anything at all.
 179  */
 180 void logevent(char *msg) {
 181 }
 182
 183 /*
 184  * Dialog-box function for the Licence box.
 185  */
 186 static int CALLBACK LicenceProc (HWND hwnd, UINT msg,
 187                                  WPARAM wParam, LPARAM lParam) {
 188     switch (msg) {
 189       case WM_INITDIALOG:
 190         return 1;
 191       case WM_COMMAND:
 192         switch (LOWORD(wParam)) {
 193           case IDOK:
 194             EndDialog(hwnd, 1);
 195             return 0;
 196         }
 197         return 0;
 198       case WM_CLOSE:
 199         EndDialog(hwnd, 1);
 200         return 0;
 201     }
 202     return 0;
 203 }
 204
 205 /*
 206  * Dialog-box function for the About box.
 207  */
 208 static int CALLBACK AboutProc (HWND hwnd, UINT msg,
 209                                WPARAM wParam, LPARAM lParam) {
 210     switch (msg) {
 211       case WM_INITDIALOG:
 212         SetDlgItemText (hwnd, 100, ver);
 213         return 1;
 214       case WM_COMMAND:
 215         switch (LOWORD(wParam)) {
 216           case IDOK:
 217             EndDialog(hwnd, 1);
 218             return 0;
 219           case 101:
 220             EnableWindow(hwnd, 0);
 221             DialogBox (hinst, MAKEINTRESOURCE(214), NULL, LicenceProc);
 222             EnableWindow(hwnd, 1);
 223             SetActiveWindow(hwnd);
 224             return 0;
 225         }
 226         return 0;
 227       case WM_CLOSE:
 228         EndDialog(hwnd, 1);
 229         return 0;
 230     }
 231     return 0;
 232 }
 233
 234 /*
 235  * Thread to generate a key.
 236  */
 237 struct rsa_key_thread_params {
 238     HWND progressbar;                  /* notify this with progress */
 239     HWND dialog;                       /* notify this on completion */
 240     struct RSAKey *key;
 241     struct RSAAux *aux;
 242 };
 243 static DWORD WINAPI generate_rsa_key_thread(void *param) {
 244     struct rsa_key_thread_params *params =
 245         (struct rsa_key_thread_params *)param;
 246     struct progress prog;
 247     prog.progbar = params->progressbar;
 248
 249     rsa_generate(params->key, params->aux, KEYSIZE, progress_update, &prog);
 250
 251     PostMessage(params->dialog, WM_DONEKEY, 0, 0);
 252
 253     free(params);
 254     return 0;
 255 }
 256
 257 struct MainDlgState {
 258     int collecting_entropy;
 259     int generation_thread_exists;
 260     int key_exists;
 261     int entropy_got, entropy_required, entropy_size;
 262     unsigned *entropy;
 263     struct RSAKey key;
 264     struct RSAAux aux;
 265 };
 266
 267 static void hidemany(HWND hwnd, const int *ids, int hideit) {
 268     while (*ids) {
 269         ShowWindow(GetDlgItem(hwnd, *ids++), (hideit ? SW_HIDE : SW_SHOW));
 270     }
 271 }
 272
 273 static void setupbigedit(HWND hwnd, int id, struct RSAKey *key) {
 274     char *buffer;
 275     char *dec1, *dec2;
 276
 277     dec1 = bignum_decimal(key->exponent);
 278     dec2 = bignum_decimal(key->modulus);
 279     buffer = malloc(strlen(dec1)+strlen(dec2)+
 280                     strlen(key->comment)+30);
 281     sprintf(buffer, "%d %s %s %s",
 282             ssh1_bignum_bitcount(key->modulus),
 283             dec1, dec2, key->comment);
 284     SetDlgItemText(hwnd, id, buffer);
 285     free(dec1);
 286     free(dec2);
 287     free(buffer);
 288 }
 289
 290 /*
 291  * Dialog-box function for the main PuTTYgen dialog box.
 292  */
 293 static int CALLBACK MainDlgProc (HWND hwnd, UINT msg,
 294                                  WPARAM wParam, LPARAM lParam) {
 295     enum {
 296         controlidstart = 100,
 297         IDC_TITLE,
 298         IDC_BOX_KEY, IDC_BOXT_KEY,
 299         IDC_NOKEY,
 300         IDC_GENERATING,
 301         IDC_PROGRESS,
 302         IDC_PKSTATIC, IDC_KEYDISPLAY,
 303         IDC_FPSTATIC, IDC_FINGERPRINT,
 304         IDC_COMMENTSTATIC, IDC_COMMENTEDIT,
 305         IDC_PASSPHRASESTATIC, IDC_PASSPHRASEEDIT,
 306         IDC_BOX_ACTIONS, IDC_BOXT_ACTIONS,
 307         IDC_GENSTATIC, IDC_GENERATE,
 308         IDC_LOADSTATIC, IDC_LOAD,
 309         IDC_SAVESTATIC, IDC_SAVE,
 310         IDC_ABOUT,
 311     };
 312     static const int nokey_ids[] = { IDC_NOKEY, 0 };
 313     static const int generating_ids[] = { IDC_GENERATING, IDC_PROGRESS, 0 };
 314     static const int gotkey_ids[] = {
 315         IDC_PKSTATIC, IDC_KEYDISPLAY,
 316         IDC_FPSTATIC, IDC_FINGERPRINT,
 317         IDC_COMMENTSTATIC, IDC_COMMENTEDIT,
 318         IDC_PASSPHRASESTATIC, IDC_PASSPHRASEEDIT, 0 };
 319     static const char generating_msg[] =
 320         "Please wait while a key is generated...";
 321     static const char entropy_msg[] =
 322         "Please move the mouse in this window to generate randomness";
 323     struct MainDlgState *state;
 324
 325     switch (msg) {
 326       case WM_INITDIALOG:
 327         state = malloc(sizeof(*state));
 328         state->generation_thread_exists = FALSE;
 329         state->key_exists = FALSE;
 330         SetWindowLong(hwnd, GWL_USERDATA, (LONG)state);
 331         {
 332             struct ctlpos cp, cp2;
 333
 334             ctlposinit(&cp, hwnd, 10, 10, 10);
 335             bartitle(&cp, "Public and private key generation for PuTTY",
 336                     IDC_TITLE);
 337             beginbox(&cp, "Key",
 338                      IDC_BOX_KEY, IDC_BOXT_KEY);
 339             cp2 = cp;
 340             statictext(&cp2, "No key.", IDC_NOKEY);
 341             cp2 = cp;
 342             statictext(&cp2, "",
 343                        IDC_GENERATING);
 344             progressbar(&cp2, IDC_PROGRESS);
 345             bigeditctrl(&cp,
 346                         "&Public key for pasting into authorized_keys file:",
 347                         IDC_PKSTATIC, IDC_KEYDISPLAY, 7);
 348             SendDlgItemMessage(hwnd, IDC_KEYDISPLAY, EM_SETREADONLY, 1, 0);
 349             staticedit(&cp, "Key fingerprint:", IDC_FPSTATIC,
 350                        IDC_FINGERPRINT, 70);
 351             SendDlgItemMessage(hwnd, IDC_FINGERPRINT, EM_SETREADONLY, 1, 0);
 352             staticedit(&cp, "Key &comment:", IDC_COMMENTSTATIC,
 353                        IDC_COMMENTEDIT, 70);
 354             staticpassedit(&cp, "Key p&assphrase:", IDC_PASSPHRASESTATIC,
 355                            IDC_PASSPHRASEEDIT, 70);
 356             endbox(&cp);
 357             beginbox(&cp, "Actions",
 358                      IDC_BOX_ACTIONS, IDC_BOXT_ACTIONS);
 359             staticbtn(&cp, "Generate a public/private key pair",
 360                       IDC_GENSTATIC, "&Generate", IDC_GENERATE);
 361             staticbtn(&cp, "Load an existing private key file",
 362                       IDC_LOADSTATIC, "&Load", IDC_LOAD);
 363             staticbtn(&cp, "Save the generated key to a new file",
 364                       IDC_SAVESTATIC, "&Save", IDC_SAVE);
 365             endbox(&cp);
 366         }
 367         /*
 368          * Initially, hide the progress bar and the key display,
 369          * and show the no-key display. Also disable the Save
 370          * button, because with no key we obviously can't save
 371          * anything.
 372          */
 373         hidemany(hwnd, nokey_ids, FALSE);
 374         hidemany(hwnd, generating_ids, TRUE);
 375         hidemany(hwnd, gotkey_ids, TRUE);
 376         EnableWindow(GetDlgItem(hwnd, IDC_SAVE), 0);
 377
 378         return 1;
 379       case WM_MOUSEMOVE:
 380         state = (struct MainDlgState *)GetWindowLong(hwnd, GWL_USERDATA);
 381         if (state->collecting_entropy) {
 382             state->entropy[state->entropy_got++] = lParam;
 383             state->entropy[state->entropy_got++] = GetMessageTime();
 384             SendDlgItemMessage(hwnd, IDC_PROGRESS, PBM_SETPOS,
 385                                state->entropy_got, 0);
 386             if (state->entropy_got >= state->entropy_required) {
 387                 struct rsa_key_thread_params *params;
 388                 DWORD threadid;
 389
 390                 /*
 391                  * Seed the entropy pool
 392                  */
 393                 random_add_heavynoise(state->entropy, state->entropy_size);
 394                 memset(state->entropy, 0, state->entropy_size);
 395                 free(state->entropy);
 396
 397                 SetDlgItemText(hwnd, IDC_GENERATING, generating_msg);
 398                 SendDlgItemMessage(hwnd, IDC_PROGRESS, PBM_SETRANGE, 0,
 399                                    MAKELPARAM(0, PROGRESSRANGE));
 400                 SendDlgItemMessage(hwnd, IDC_PROGRESS, PBM_SETPOS, 0, 0);
 401
 402                 params = malloc(sizeof(*params));
 403                 params->progressbar = GetDlgItem(hwnd, IDC_PROGRESS);
 404                 params->dialog = hwnd;
 405                 params->key = &state->key;
 406                 params->aux = &state->aux;
 407
 408                 if (!CreateThread(NULL, 0, generate_rsa_key_thread,
 409                                   params, 0, &threadid)) {
 410                     MessageBox(hwnd, "Out of thread resources",
 411                                "Key generation error",
 412                                MB_OK | MB_ICONERROR);
 413                     free(params);
 414                 } else {
 415                     state->generation_thread_exists = TRUE;
 416                     state->collecting_entropy = FALSE;
 417                 }
 418             }
 419         }
 420         break;
 421       case WM_COMMAND:
 422         switch (LOWORD(wParam)) {
 423           case IDC_COMMENTEDIT:
 424             if (HIWORD(wParam) == EN_CHANGE) {
 425                 state = (struct MainDlgState *)
 426                     GetWindowLong(hwnd, GWL_USERDATA);
 427                 if (state->key_exists) {
 428                     HWND editctl = GetDlgItem(hwnd, IDC_COMMENTEDIT);
 429                     int len = GetWindowTextLength(editctl);
 430                     if (state->key.comment)
 431                         free(state->key.comment);
 432                     state->key.comment = malloc(len+1);
 433                     GetWindowText(editctl, state->key.comment, len+1);
 434                 }
 435             }
 436             break;
 437           case IDC_ABOUT:
 438             EnableWindow(hwnd, 0);
 439             DialogBox (hinst, MAKEINTRESOURCE(213), NULL, AboutProc);
 440             EnableWindow(hwnd, 1);
 441             SetActiveWindow(hwnd);
 442             return 0;
 443           case IDC_GENERATE:
 444             state = (struct MainDlgState *)GetWindowLong(hwnd, GWL_USERDATA);
 445             if (!state->generation_thread_exists) {
 446                 hidemany(hwnd, nokey_ids, TRUE);
 447                 hidemany(hwnd, generating_ids, FALSE);
 448                 hidemany(hwnd, gotkey_ids, TRUE);
 449                 EnableWindow(GetDlgItem(hwnd, IDC_GENERATE), 0);
 450                 EnableWindow(GetDlgItem(hwnd, IDC_LOAD), 0);
 451                 EnableWindow(GetDlgItem(hwnd, IDC_SAVE), 0);
 452                 state->key_exists = FALSE;
 453                 SetDlgItemText(hwnd, IDC_GENERATING, entropy_msg);
 454                 state->collecting_entropy = TRUE;
 455
 456                 /*
 457                  * My brief statistical tests on mouse movements
 458                  * suggest that there are about 5 bits of
 459                  * randomness in the x position, 5 in the y
 460                  * position, and 1.7 in the message time, making
 461                  * 11.7 bits of unpredictability per mouse
 462                  * movement. However, other people have told me
 463                  * it's far less than that, so I'm going to be
 464                  * stupidly cautious and knock that down to a nice
 465                  * round 4.
 466                  */
 467                 state->entropy_required = (KEYSIZE / 4) * 2;
 468                 state->entropy_got = 0;
 469                 state->entropy_size = (state->entropy_required *
 470                                        sizeof(*state->entropy));
 471                 state->entropy = malloc(state->entropy_size);
 472
 473                 SendDlgItemMessage(hwnd, IDC_PROGRESS, PBM_SETRANGE, 0,
 474                                    MAKELPARAM(0, state->entropy_required));
 475                 SendDlgItemMessage(hwnd, IDC_PROGRESS, PBM_SETPOS, 0, 0);
 476             }
 477             break;
 478           case IDC_SAVE:
 479             state = (struct MainDlgState *)GetWindowLong(hwnd, GWL_USERDATA);
 480             if (state->key_exists) {
 481                 char filename[FILENAME_MAX];
 482                 char passphrase[PASSPHRASE_MAXLEN];
 483                 GetDlgItemText(hwnd, IDC_PASSPHRASEEDIT,
 484                                passphrase, sizeof(passphrase)-1);
 485                 if (!*passphrase) {
 486                     int ret;
 487                     ret = MessageBox(hwnd,
 488                                      "Are you sure you want to save this key\n"
 489                                      "without a passphrase to protect it?",
 490                                      "PuTTYgen Warning",
 491                                      MB_YESNO | MB_ICONWARNING);
 492                     if (ret != IDYES)
 493                         break;
 494                 }
 495                 if (prompt_keyfile(hwnd, "Save private key as:",
 496                                    filename, 1)) {
 497                     /* FIXME: prompt before overwriting */
 498                     saversakey(filename, &state->key, &state->aux,
 499                                *passphrase ? passphrase : NULL);
 500                     /* FIXME: check return value */
 501                 }
 502             }
 503             break;
 504           case IDC_LOAD:
 505             state = (struct MainDlgState *)GetWindowLong(hwnd, GWL_USERDATA);
 506             if (!state->generation_thread_exists) {
 507                 char filename[FILENAME_MAX];
 508                 if (prompt_keyfile(hwnd, "Load private key:",
 509                                    filename, 0)) {
 510                     char passphrase[PASSPHRASE_MAXLEN];
 511                     int needs_pass;
 512                     int ret;
 513                     char *comment;
 514                     struct PassphraseProcStruct pps;
 515                     struct RSAKey newkey;
 516                     struct RSAAux newaux;
 517
 518                     needs_pass = rsakey_encrypted(filename, &comment);
 519                     pps.passphrase = passphrase;
 520                     pps.comment = comment;
 521                     do {
 522                         if (needs_pass) {
 523                             int dlgret;
 524                             dlgret = DialogBoxParam(hinst,
 525                                                     MAKEINTRESOURCE(210),
 526                                                     NULL, PassphraseProc,
 527                                                     (LPARAM)&pps);
 528                             if (!dlgret) {
 529                                 ret = -2;
 530                                 break;
 531                             }
 532                         } else
 533                             *passphrase = '\0';
 534                         ret = loadrsakey(filename, &newkey, &newaux,
 535                                          passphrase);
 536                     } while (ret == -1);
 537                     if (comment) free(comment);
 538                     if (ret == 0) {
 539                         MessageBox(NULL, "Couldn't load private key.",
 540                                    "PuTTYgen Error", MB_OK | MB_ICONERROR);
 541                     } else if (ret == 1) {
 542                         state->key = newkey;
 543                         state->aux = newaux;
 544
 545                         EnableWindow(GetDlgItem(hwnd, IDC_GENERATE), 1);
 546                         EnableWindow(GetDlgItem(hwnd, IDC_LOAD), 1);
 547                         EnableWindow(GetDlgItem(hwnd, IDC_SAVE), 1);
 548                         /*
 549                          * Now update the key controls with all the
 550                          * key data.
 551                          */
 552                         {
 553                             char buf[128];
 554                             SetDlgItemText(hwnd, IDC_PASSPHRASEEDIT,
 555                                            passphrase);
 556                             SetDlgItemText(hwnd, IDC_COMMENTEDIT,
 557                                            state->key.comment);
 558                             /*
 559                              * Set the key fingerprint.
 560                              */
 561                             {
 562                                 char *savecomment = state->key.comment;
 563                                 state->key.comment = NULL;
 564                                 rsa_fingerprint(buf, sizeof(buf), &state->key);
 565                                 state->key.comment = savecomment;
 566                             }
 567                             SetDlgItemText(hwnd, IDC_FINGERPRINT, buf);
 568                             /*
 569                              * Construct a decimal representation
 570                              * of the key, for pasting into
 571                              * .ssh/authorized_keys on a Unix box.
 572                              */
 573                             setupbigedit(hwnd, IDC_KEYDISPLAY, &state->key);
 574                         }
 575                         /*
 576                          * Finally, hide the progress bar and show
 577                          * the key data.
 578                          */
 579                         hidemany(hwnd, nokey_ids, TRUE);
 580                         hidemany(hwnd, generating_ids, TRUE);
 581                         hidemany(hwnd, gotkey_ids, FALSE);
 582                         state->key_exists = TRUE;
 583                     }
 584                 }
 585             }
 586             break;
 587         }
 588         return 0;
 589       case WM_DONEKEY:
 590         state = (struct MainDlgState *)GetWindowLong(hwnd, GWL_USERDATA);
 591         state->generation_thread_exists = FALSE;
 592         state->key_exists = TRUE;
 593         SendDlgItemMessage(hwnd, IDC_PROGRESS, PBM_SETPOS, PROGRESSRANGE, 0);
 594         EnableWindow(GetDlgItem(hwnd, IDC_GENERATE), 1);
 595         EnableWindow(GetDlgItem(hwnd, IDC_LOAD), 1);
 596         EnableWindow(GetDlgItem(hwnd, IDC_SAVE), 1);
 597         /*
 598          * Invent a comment for the key. We'll do this by including
 599          * the date in it. This will be so horrifyingly ugly that
 600          * the user will immediately want to change it, which is
 601          * what we want :-)
 602          */
 603         state->key.comment = malloc(30);
 604         {
 605             time_t t;
 606             struct tm *tm;
 607             time(&t);
 608             tm = localtime(&t);
 609             strftime(state->key.comment, 30, "rsa-key-%Y%m%d", tm);
 610         }
 611
 612         /*
 613          * Now update the key controls with all the key data.
 614          */
 615         {
 616             char buf[128];
 617             /*
 618              * Blank passphrase, initially. This isn't dangerous,
 619              * because we will warn (Are You Sure?) before allowing
 620              * the user to save an unprotected private key.
 621              */
 622             SetDlgItemText(hwnd, IDC_PASSPHRASEEDIT, "");
 623             /*
 624              * Set the comment.
 625              */
 626             SetDlgItemText(hwnd, IDC_COMMENTEDIT, state->key.comment);
 627             /*
 628              * Set the key fingerprint.
 629              */
 630             {
 631                 char *savecomment = state->key.comment;
 632                 state->key.comment = NULL;
 633                 rsa_fingerprint(buf, sizeof(buf), &state->key);
 634                 state->key.comment = savecomment;
 635             }
 636             SetDlgItemText(hwnd, IDC_FINGERPRINT, buf);
 637             /*
 638              * Construct a decimal representation of the key, for
 639              * pasting into .ssh/authorized_keys on a Unix box.
 640              */
 641             setupbigedit(hwnd, IDC_KEYDISPLAY, &state->key);
 642         }
 643         /*
 644          * Finally, hide the progress bar and show the key data.
 645          */
 646         hidemany(hwnd, nokey_ids, TRUE);
 647         hidemany(hwnd, generating_ids, TRUE);
 648         hidemany(hwnd, gotkey_ids, FALSE);
 649         break;
 650       case WM_CLOSE:
 651         state = (struct MainDlgState *)GetWindowLong(hwnd, GWL_USERDATA);
 652         free(state);
 653         EndDialog(hwnd, 1);
 654         return 0;
 655     }
 656     return 0;
 657 }
 658
 659 int WINAPI WinMain(HINSTANCE inst, HINSTANCE prev, LPSTR cmdline, int show) {
 660     InitCommonControls();
 661     hinst = inst;
 662     random_init();
 663     return DialogBox(hinst, MAKEINTRESOURCE(201), NULL, MainDlgProc) != IDOK;
 664 }