puttygen.c

   1 /*
   2  * PuTTY key generation front end.
   3  */
   4
   5 #include <windows.h>
   6 #include <commctrl.h>
   7 #include <time.h>
   8 #include <stdio.h>
   9 #include <stdlib.h>
  10
  11 #define PUTTY_DO_GLOBALS
  12
  13 #include "putty.h"
  14 #include "ssh.h"
  15 #include "winstuff.h"
  16
  17 #define WM_DONEKEY (WM_XUSER + 1)
  18
  19 #define DEFAULT_KEYSIZE 1024
  20
  21 /* ----------------------------------------------------------------------
  22  * Progress report code. This is really horrible :-)
  23  */
  24 #define PHASE1TOTAL 0x10000
  25 #define PHASE2TOTAL 0x10000
  26 #define PHASE3TOTAL 0x04000
  27 #define PHASE1START 0
  28 #define PHASE2START (PHASE1TOTAL)
  29 #define PHASE3START (PHASE1TOTAL + PHASE2TOTAL)
  30 #define TOTALTOTAL  (PHASE1TOTAL + PHASE2TOTAL + PHASE3TOTAL)
  31 #define PROGRESSBIGRANGE 65535
  32 #define DIVISOR     ((TOTALTOTAL + PROGRESSBIGRANGE - 1) / PROGRESSBIGRANGE)
  33 #define PROGRESSRANGE (TOTALTOTAL / DIVISOR)
  34 struct progress {
  35     unsigned phase1param, phase1current, phase1n;
  36     unsigned phase2param, phase2current, phase2n;
  37     unsigned phase3mult;
  38     HWND progbar;
  39 };
  40
  41 static void progress_update(void *param, int phase, int iprogress) {
  42     struct progress *p = (struct progress *)param;
  43     unsigned progress = iprogress;
  44     int position;
  45
  46     switch (phase) {
  47       case -1:
  48         p->phase1param = 0x10000 + progress;
  49         p->phase1current = 0x10000; p->phase1n = 0;
  50         return;
  51       case -2:
  52         p->phase2param = 0x10000 + progress;
  53         p->phase2current = 0x10000; p->phase2n = 0;
  54         return;
  55       case -3:
  56         p->phase3mult = PHASE3TOTAL / progress;
  57         return;
  58       case 1:
  59         while (p->phase1n < progress) {
  60             p->phase1n++;
  61             p->phase1current *= p->phase1param;
  62             p->phase1current /= 0x10000;
  63         }
  64         position = PHASE1START + 0x10000 - p->phase1current;
  65         break;
  66       case 2:
  67         while (p->phase2n < progress) {
  68             p->phase2n++;
  69             p->phase2current *= p->phase2param;
  70             p->phase2current /= 0x10000;
  71         }
  72         position = PHASE2START + 0x10000 - p->phase2current;
  73         break;
  74       case 3:
  75         position = PHASE3START + progress * p->phase3mult;
  76         break;
  77     }
  78
  79     SendMessage(p->progbar, PBM_SETPOS, position / DIVISOR, 0);
  80 }
  81
  82 extern char ver[];
  83
  84 #define PASSPHRASE_MAXLEN 512
  85
  86 struct PassphraseProcStruct {
  87     char *passphrase;
  88     char *comment;
  89 };
  90
  91 /*
  92  * Dialog-box function for the passphrase box.
  93  */
  94 static int CALLBACK PassphraseProc(HWND hwnd, UINT msg,
  95                                    WPARAM wParam, LPARAM lParam) {
  96     static char *passphrase;
  97     struct PassphraseProcStruct *p;
  98
  99     switch (msg) {
 100       case WM_INITDIALOG:
 101         SetForegroundWindow(hwnd);
 102         SetWindowPos (hwnd, HWND_TOP, 0, 0, 0, 0,
 103                       SWP_NOMOVE | SWP_NOSIZE | SWP_SHOWWINDOW);
 104
 105         /*
 106          * Centre the window.
 107          */
 108         {                              /* centre the window */
 109             RECT rs, rd;
 110             HWND hw;
 111
 112             hw = GetDesktopWindow();
 113             if (GetWindowRect (hw, &rs) && GetWindowRect (hwnd, &rd))
 114                 MoveWindow (hwnd, (rs.right + rs.left + rd.left - rd.right)/2,
 115                             (rs.bottom + rs.top + rd.top - rd.bottom)/2,
 116                             rd.right-rd.left, rd.bottom-rd.top, TRUE);
 117         }
 118
 119         p = (struct PassphraseProcStruct *)lParam;
 120         passphrase = p->passphrase;
 121         if (p->comment)
 122             SetDlgItemText(hwnd, 101, p->comment);
 123         *passphrase = 0;
 124         return 0;
 125       case WM_COMMAND:
 126         switch (LOWORD(wParam)) {
 127           case IDOK:
 128             if (*passphrase)
 129                 EndDialog (hwnd, 1);
 130             else
 131                 MessageBeep (0);
 132             return 0;
 133           case IDCANCEL:
 134             EndDialog (hwnd, 0);
 135             return 0;
 136           case 102:                    /* edit box */
 137             if (HIWORD(wParam) == EN_CHANGE) {
 138                 GetDlgItemText (hwnd, 102, passphrase, PASSPHRASE_MAXLEN-1);
 139                 passphrase[PASSPHRASE_MAXLEN-1] = '\0';
 140             }
 141             return 0;
 142         }
 143         return 0;
 144       case WM_CLOSE:
 145         EndDialog (hwnd, 0);
 146         return 0;
 147     }
 148     return 0;
 149 }
 150
 151 /*
 152  * Prompt for a key file. Assumes the filename buffer is of size
 153  * FILENAME_MAX.
 154  */
 155 static int prompt_keyfile(HWND hwnd, char *dlgtitle,
 156                           char *filename, int save) {
 157     OPENFILENAME of;
 158     memset(&of, 0, sizeof(of));
 159 #ifdef OPENFILENAME_SIZE_VERSION_400
 160     of.lStructSize = OPENFILENAME_SIZE_VERSION_400;
 161 #else
 162     of.lStructSize = sizeof(of);
 163 #endif
 164     of.hwndOwner = hwnd;
 165     of.lpstrFilter = "All Files\0*\0\0\0";
 166     of.lpstrCustomFilter = NULL;
 167     of.nFilterIndex = 1;
 168     of.lpstrFile = filename; *filename = '\0';
 169     of.nMaxFile = FILENAME_MAX;
 170     of.lpstrFileTitle = NULL;
 171     of.lpstrInitialDir = NULL;
 172     of.lpstrTitle = dlgtitle;
 173     of.Flags = 0;
 174     if (save)
 175         return GetSaveFileName(&of);
 176     else
 177         return GetOpenFileName(&of);
 178 }
 179
 180 /*
 181  * This function is needed to link with the DES code. We need not
 182  * have it do anything at all.
 183  */
 184 void logevent(char *msg) {
 185 }
 186
 187 /*
 188  * Dialog-box function for the Licence box.
 189  */
 190 static int CALLBACK LicenceProc (HWND hwnd, UINT msg,
 191                                  WPARAM wParam, LPARAM lParam) {
 192     switch (msg) {
 193       case WM_INITDIALOG:
 194         /*
 195          * Centre the window.
 196          */
 197         {                              /* centre the window */
 198             RECT rs, rd;
 199             HWND hw;
 200
 201             hw = GetDesktopWindow();
 202             if (GetWindowRect (hw, &rs) && GetWindowRect (hwnd, &rd))
 203                 MoveWindow (hwnd, (rs.right + rs.left + rd.left - rd.right)/2,
 204                             (rs.bottom + rs.top + rd.top - rd.bottom)/2,
 205                             rd.right-rd.left, rd.bottom-rd.top, TRUE);
 206         }
 207
 208         return 1;
 209       case WM_COMMAND:
 210         switch (LOWORD(wParam)) {
 211           case IDOK:
 212             EndDialog(hwnd, 1);
 213             return 0;
 214         }
 215         return 0;
 216       case WM_CLOSE:
 217         EndDialog(hwnd, 1);
 218         return 0;
 219     }
 220     return 0;
 221 }
 222
 223 /*
 224  * Dialog-box function for the About box.
 225  */
 226 static int CALLBACK AboutProc (HWND hwnd, UINT msg,
 227                                WPARAM wParam, LPARAM lParam) {
 228     switch (msg) {
 229       case WM_INITDIALOG:
 230         /*
 231          * Centre the window.
 232          */
 233         {                              /* centre the window */
 234             RECT rs, rd;
 235             HWND hw;
 236
 237             hw = GetDesktopWindow();
 238             if (GetWindowRect (hw, &rs) && GetWindowRect (hwnd, &rd))
 239                 MoveWindow (hwnd, (rs.right + rs.left + rd.left - rd.right)/2,
 240                             (rs.bottom + rs.top + rd.top - rd.bottom)/2,
 241                             rd.right-rd.left, rd.bottom-rd.top, TRUE);
 242         }
 243
 244         SetDlgItemText (hwnd, 100, ver);
 245         return 1;
 246       case WM_COMMAND:
 247         switch (LOWORD(wParam)) {
 248           case IDOK:
 249             EndDialog(hwnd, 1);
 250             return 0;
 251           case 101:
 252             EnableWindow(hwnd, 0);
 253             DialogBox (hinst, MAKEINTRESOURCE(214), NULL, LicenceProc);
 254             EnableWindow(hwnd, 1);
 255             SetActiveWindow(hwnd);
 256             return 0;
 257         }
 258         return 0;
 259       case WM_CLOSE:
 260         EndDialog(hwnd, 1);
 261         return 0;
 262     }
 263     return 0;
 264 }
 265
 266 /*
 267  * Thread to generate a key.
 268  */
 269 struct rsa_key_thread_params {
 270     HWND progressbar;                  /* notify this with progress */
 271     HWND dialog;                       /* notify this on completion */
 272     int keysize;                       /* bits in key */
 273     struct RSAKey *key;
 274 };
 275 static DWORD WINAPI generate_rsa_key_thread(void *param) {
 276     struct rsa_key_thread_params *params =
 277         (struct rsa_key_thread_params *)param;
 278     struct progress prog;
 279     prog.progbar = params->progressbar;
 280
 281     rsa_generate(params->key, params->keysize, progress_update, &prog);
 282
 283     PostMessage(params->dialog, WM_DONEKEY, 0, 0);
 284
 285     sfree(params);
 286     return 0;
 287 }
 288
 289 struct MainDlgState {
 290     int collecting_entropy;
 291     int generation_thread_exists;
 292     int key_exists;
 293     int entropy_got, entropy_required, entropy_size;
 294     int keysize;
 295     int ssh2;
 296     char **commentptr;                 /* points to key.comment or ssh2key.comment */
 297     struct ssh2_userkey ssh2key;
 298     unsigned *entropy;
 299     struct RSAKey key;
 300 };
 301
 302 static void hidemany(HWND hwnd, const int *ids, int hideit) {
 303     while (*ids) {
 304         ShowWindow(GetDlgItem(hwnd, *ids++), (hideit ? SW_HIDE : SW_SHOW));
 305     }
 306 }
 307
 308 static void setupbigedit1(HWND hwnd, int id, struct RSAKey *key) {
 309     char *buffer;
 310     char *dec1, *dec2;
 311
 312     dec1 = bignum_decimal(key->exponent);
 313     dec2 = bignum_decimal(key->modulus);
 314     buffer = smalloc(strlen(dec1)+strlen(dec2)+
 315                      strlen(key->comment)+30);
 316     sprintf(buffer, "%d %s %s %s",
 317             bignum_bitcount(key->modulus),
 318             dec1, dec2, key->comment);
 319     SetDlgItemText(hwnd, id, buffer);
 320     sfree(dec1);
 321     sfree(dec2);
 322     sfree(buffer);
 323 }
 324
 325 static void setupbigedit2(HWND hwnd, int id, struct ssh2_userkey *key) {
 326     unsigned char *pub_blob;
 327     char *buffer, *p;
 328     int pub_len;
 329     int i;
 330
 331     pub_blob = key->alg->public_blob(key->data, &pub_len);
 332     buffer = smalloc(strlen(key->alg->name) + 4*((pub_len+2)/3) +
 333                      strlen(key->comment) + 3);
 334     strcpy(buffer, key->alg->name);
 335     p = buffer + strlen(buffer);
 336     *p++ = ' ';
 337     i = 0;
 338     while (i < pub_len) {
 339         int n = (pub_len-i < 3 ? pub_len-i : 3);
 340         base64_encode_atom(pub_blob+i, n, p);
 341         i += n;
 342         p += 4;
 343     }
 344     *p++ = ' ';
 345     strcpy(p, key->comment);
 346     SetDlgItemText(hwnd, id, buffer);
 347     sfree(pub_blob);
 348     sfree(buffer);
 349 }
 350
 351 /*
 352  * Dialog-box function for the main PuTTYgen dialog box.
 353  */
 354 static int CALLBACK MainDlgProc (HWND hwnd, UINT msg,
 355                                  WPARAM wParam, LPARAM lParam) {
 356     enum {
 357         controlidstart = 100,
 358         IDC_TITLE,
 359         IDC_BOX_KEY,
 360         IDC_NOKEY,
 361         IDC_GENERATING,
 362         IDC_PROGRESS,
 363         IDC_PKSTATIC, IDC_KEYDISPLAY,
 364         IDC_FPSTATIC, IDC_FINGERPRINT,
 365         IDC_COMMENTSTATIC, IDC_COMMENTEDIT,
 366         IDC_PASSPHRASE1STATIC, IDC_PASSPHRASE1EDIT,
 367         IDC_PASSPHRASE2STATIC, IDC_PASSPHRASE2EDIT,
 368         IDC_BOX_ACTIONS,
 369         IDC_GENSTATIC, IDC_GENERATE,
 370         IDC_LOADSTATIC, IDC_LOAD,
 371         IDC_SAVESTATIC, IDC_SAVE,
 372         IDC_BOX_PARAMS,
 373         IDC_TYPESTATIC, IDC_KEYSSH1, IDC_KEYSSH2RSA,
 374         IDC_BITSSTATIC, IDC_BITS,
 375         IDC_ABOUT,
 376     };
 377     static const int nokey_ids[] = { IDC_NOKEY, 0 };
 378     static const int generating_ids[] = { IDC_GENERATING, IDC_PROGRESS, 0 };
 379     static const int gotkey_ids[] = {
 380         IDC_PKSTATIC, IDC_KEYDISPLAY,
 381         IDC_FPSTATIC, IDC_FINGERPRINT,
 382         IDC_COMMENTSTATIC, IDC_COMMENTEDIT,
 383         IDC_PASSPHRASE1STATIC, IDC_PASSPHRASE1EDIT,
 384         IDC_PASSPHRASE2STATIC, IDC_PASSPHRASE2EDIT, 0 };
 385     static const char generating_msg[] =
 386         "Please wait while a key is generated...";
 387     static const char entropy_msg[] =
 388         "Please generate some randomness by moving the mouse over the blank area.";
 389     struct MainDlgState *state;
 390
 391     switch (msg) {
 392       case WM_INITDIALOG:
 393         /*
 394          * Centre the window.
 395          */
 396         {                              /* centre the window */
 397             RECT rs, rd;
 398             HWND hw;
 399
 400             hw = GetDesktopWindow();
 401             if (GetWindowRect (hw, &rs) && GetWindowRect (hwnd, &rd))
 402                 MoveWindow (hwnd, (rs.right + rs.left + rd.left - rd.right)/2,
 403                             (rs.bottom + rs.top + rd.top - rd.bottom)/2,
 404                             rd.right-rd.left, rd.bottom-rd.top, TRUE);
 405         }
 406
 407         state = smalloc(sizeof(*state));
 408         state->generation_thread_exists = FALSE;
 409         state->collecting_entropy = FALSE;
 410         state->entropy = NULL;
 411         state->key_exists = FALSE;
 412         SetWindowLong(hwnd, GWL_USERDATA, (LONG)state);
 413         {
 414             struct ctlpos cp, cp2;
 415
 416             /* Accelerators used: acglops */
 417
 418             ctlposinit(&cp, hwnd, 10, 10, 10);
 419             bartitle(&cp, "Public and private key generation for PuTTY",
 420                     IDC_TITLE);
 421             beginbox(&cp, "Key",
 422                      IDC_BOX_KEY);
 423             cp2 = cp;
 424             statictext(&cp2, "No key.", IDC_NOKEY);
 425             cp2 = cp;
 426             statictext(&cp2, "",
 427                        IDC_GENERATING);
 428             progressbar(&cp2, IDC_PROGRESS);
 429             bigeditctrl(&cp,
 430                         "&Public key for pasting into authorized_keys file:",
 431                         IDC_PKSTATIC, IDC_KEYDISPLAY, 7);
 432             SendDlgItemMessage(hwnd, IDC_KEYDISPLAY, EM_SETREADONLY, 1, 0);
 433             staticedit(&cp, "Key fingerprint:", IDC_FPSTATIC,
 434                        IDC_FINGERPRINT, 75);
 435             SendDlgItemMessage(hwnd, IDC_FINGERPRINT, EM_SETREADONLY, 1, 0);
 436             staticedit(&cp, "Key &comment:", IDC_COMMENTSTATIC,
 437                        IDC_COMMENTEDIT, 75);
 438             staticpassedit(&cp, "Key p&assphrase:", IDC_PASSPHRASE1STATIC,
 439                            IDC_PASSPHRASE1EDIT, 75);
 440             staticpassedit(&cp, "C&onfirm passphrase:", IDC_PASSPHRASE2STATIC,
 441                            IDC_PASSPHRASE2EDIT, 75);
 442             endbox(&cp);
 443             beginbox(&cp, "Actions",
 444                      IDC_BOX_ACTIONS);
 445             staticbtn(&cp, "Generate a public/private key pair",
 446                       IDC_GENSTATIC, "&Generate", IDC_GENERATE);
 447             staticbtn(&cp, "Load an existing private key file",
 448                       IDC_LOADSTATIC, "&Load", IDC_LOAD);
 449             staticbtn(&cp, "Save the generated key to a new file",
 450                       IDC_SAVESTATIC, "&Save", IDC_SAVE);
 451             endbox(&cp);
 452             beginbox(&cp, "Parameters",
 453                      IDC_BOX_PARAMS);
 454             radioline(&cp, "Type of key to generate:", IDC_TYPESTATIC, 2,
 455                           "SSH&1 (RSA)", IDC_KEYSSH1,
 456                           "SSH2 &RSA", IDC_KEYSSH2RSA, NULL);
 457             staticedit(&cp, "Number of &bits in a generated key:",
 458                        IDC_BITSSTATIC, IDC_BITS, 20);
 459             endbox(&cp);
 460         }
 461         CheckRadioButton(hwnd, IDC_KEYSSH1, IDC_KEYSSH2RSA, IDC_KEYSSH1);
 462         SetDlgItemInt(hwnd, IDC_BITS, DEFAULT_KEYSIZE, FALSE);
 463
 464         /*
 465          * Initially, hide the progress bar and the key display,
 466          * and show the no-key display. Also disable the Save
 467          * button, because with no key we obviously can't save
 468          * anything.
 469          */
 470         hidemany(hwnd, nokey_ids, FALSE);
 471         hidemany(hwnd, generating_ids, TRUE);
 472         hidemany(hwnd, gotkey_ids, TRUE);
 473         EnableWindow(GetDlgItem(hwnd, IDC_SAVE), 0);
 474
 475         return 1;
 476       case WM_MOUSEMOVE:
 477         state = (struct MainDlgState *)GetWindowLong(hwnd, GWL_USERDATA);
 478         if (state->collecting_entropy &&
 479             state->entropy &&
 480             state->entropy_got < state->entropy_required) {
 481             state->entropy[state->entropy_got++] = lParam;
 482             state->entropy[state->entropy_got++] = GetMessageTime();
 483             SendDlgItemMessage(hwnd, IDC_PROGRESS, PBM_SETPOS,
 484                                state->entropy_got, 0);
 485             if (state->entropy_got >= state->entropy_required) {
 486                 struct rsa_key_thread_params *params;
 487                 DWORD threadid;
 488
 489                 /*
 490                  * Seed the entropy pool
 491                  */
 492                 random_add_heavynoise(state->entropy, state->entropy_size);
 493                 memset(state->entropy, 0, state->entropy_size);
 494                 sfree(state->entropy);
 495                 state->collecting_entropy = FALSE;
 496
 497                 SetDlgItemText(hwnd, IDC_GENERATING, generating_msg);
 498                 SendDlgItemMessage(hwnd, IDC_PROGRESS, PBM_SETRANGE, 0,
 499                                    MAKELPARAM(0, PROGRESSRANGE));
 500                 SendDlgItemMessage(hwnd, IDC_PROGRESS, PBM_SETPOS, 0, 0);
 501
 502                 params = smalloc(sizeof(*params));
 503                 params->progressbar = GetDlgItem(hwnd, IDC_PROGRESS);
 504                 params->dialog = hwnd;
 505                 params->keysize = state->keysize;
 506                 params->key = &state->key;
 507
 508                 if (!CreateThread(NULL, 0, generate_rsa_key_thread,
 509                                   params, 0, &threadid)) {
 510                     MessageBox(hwnd, "Out of thread resources",
 511                                "Key generation error",
 512                                MB_OK | MB_ICONERROR);
 513                     sfree(params);
 514                 } else {
 515                     state->generation_thread_exists = TRUE;
 516                 }
 517             }
 518         }
 519         break;
 520       case WM_COMMAND:
 521         switch (LOWORD(wParam)) {
 522           case IDC_COMMENTEDIT:
 523             if (HIWORD(wParam) == EN_CHANGE) {
 524                 state = (struct MainDlgState *)
 525                     GetWindowLong(hwnd, GWL_USERDATA);
 526                 if (state->key_exists) {
 527                     HWND editctl = GetDlgItem(hwnd, IDC_COMMENTEDIT);
 528                     int len = GetWindowTextLength(editctl);
 529                     if (*state->commentptr)
 530                         sfree(*state->commentptr);
 531                     *state->commentptr = smalloc(len+1);
 532                     GetWindowText(editctl, *state->commentptr, len+1);
 533                     if (state->ssh2) {
 534                         setupbigedit2(hwnd, IDC_KEYDISPLAY, &state->ssh2key);
 535                     } else {
 536                         setupbigedit1(hwnd, IDC_KEYDISPLAY, &state->key);
 537                     }
 538                 }
 539             }
 540             break;
 541           case IDC_ABOUT:
 542             EnableWindow(hwnd, 0);
 543             DialogBox (hinst, MAKEINTRESOURCE(213), NULL, AboutProc);
 544             EnableWindow(hwnd, 1);
 545             SetActiveWindow(hwnd);
 546             return 0;
 547           case IDC_GENERATE:
 548             state = (struct MainDlgState *)GetWindowLong(hwnd, GWL_USERDATA);
 549             if (!state->generation_thread_exists) {
 550                 BOOL ok;
 551                 state->keysize = GetDlgItemInt(hwnd, IDC_BITS,
 552                                                &ok, FALSE);
 553                 if (!ok) state->keysize = DEFAULT_KEYSIZE;
 554                 /* If we ever introduce a new key type, check it here! */
 555                 state->ssh2 = !IsDlgButtonChecked(hwnd, IDC_KEYSSH1);
 556                 if (state->keysize < 256) {
 557                     int ret = MessageBox(hwnd,
 558                                          "PuTTYgen will not generate a key"
 559                                          " smaller than 256 bits.\n"
 560                                          "Key length reset to 256. Continue?",
 561                                          "PuTTYgen Warning",
 562                                          MB_ICONWARNING | MB_OKCANCEL);
 563                     if (ret != IDOK)
 564                         break;
 565                     state->keysize = 256;
 566                     SetDlgItemInt(hwnd, IDC_BITS, 256, FALSE);
 567                 }
 568                 hidemany(hwnd, nokey_ids, TRUE);
 569                 hidemany(hwnd, generating_ids, FALSE);
 570                 hidemany(hwnd, gotkey_ids, TRUE);
 571                 EnableWindow(GetDlgItem(hwnd, IDC_GENERATE), 0);
 572                 EnableWindow(GetDlgItem(hwnd, IDC_LOAD), 0);
 573                 EnableWindow(GetDlgItem(hwnd, IDC_SAVE), 0);
 574                 state->key_exists = FALSE;
 575                 SetDlgItemText(hwnd, IDC_GENERATING, entropy_msg);
 576                 state->collecting_entropy = TRUE;
 577
 578                 /*
 579                  * My brief statistical tests on mouse movements
 580                  * suggest that there are about 2.5 bits of
 581                  * randomness in the x position, 2.5 in the y
 582                  * position, and 1.7 in the message time, making
 583                  * 5.7 bits of unpredictability per mouse movement.
 584                  * However, other people have told me it's far less
 585                  * than that, so I'm going to be stupidly cautious
 586                  * and knock that down to a nice round 2. With this
 587                  * method, we require two words per mouse movement,
 588                  * so with 2 bits per mouse movement we expect 2
 589                  * bits every 2 words.
 590                  */
 591                 state->entropy_required = (state->keysize/2) * 2;
 592                 state->entropy_got = 0;
 593                 state->entropy_size = (state->entropy_required *
 594                                        sizeof(*state->entropy));
 595                 state->entropy = smalloc(state->entropy_size);
 596
 597                 SendDlgItemMessage(hwnd, IDC_PROGRESS, PBM_SETRANGE, 0,
 598                                    MAKELPARAM(0, state->entropy_required));
 599                 SendDlgItemMessage(hwnd, IDC_PROGRESS, PBM_SETPOS, 0, 0);
 600             }
 601             break;
 602           case IDC_SAVE:
 603             state = (struct MainDlgState *)GetWindowLong(hwnd, GWL_USERDATA);
 604             if (state->key_exists) {
 605                 char filename[FILENAME_MAX];
 606                 char passphrase[PASSPHRASE_MAXLEN];
 607                 char passphrase2[PASSPHRASE_MAXLEN];
 608                 GetDlgItemText(hwnd, IDC_PASSPHRASE1EDIT,
 609                                passphrase, sizeof(passphrase));
 610                 GetDlgItemText(hwnd, IDC_PASSPHRASE2EDIT,
 611                                passphrase2, sizeof(passphrase2));
 612                 if (strcmp(passphrase, passphrase2)) {
 613                     MessageBox(hwnd,
 614                                "The two passphrases given do not match.",
 615                                "PuTTYgen Error",
 616                                MB_OK | MB_ICONERROR);
 617                     break;
 618                 }
 619                 if (!*passphrase) {
 620                     int ret;
 621                     ret = MessageBox(hwnd,
 622                                      "Are you sure you want to save this key\n"
 623                                      "without a passphrase to protect it?",
 624                                      "PuTTYgen Warning",
 625                                      MB_YESNO | MB_ICONWARNING);
 626                     if (ret != IDYES)
 627                         break;
 628                 }
 629                 if (prompt_keyfile(hwnd, "Save private key as:",
 630                                    filename, 1)) {
 631                     int ret;
 632                     FILE *fp = fopen(filename, "r");
 633                     if (fp) {
 634                         char buffer[FILENAME_MAX+80];
 635                         fclose(fp);
 636                         sprintf(buffer, "Overwrite existing file\n%.*s?",
 637                                 FILENAME_MAX, filename);
 638                         ret = MessageBox(hwnd, buffer, "PuTTYgen Warning",
 639                                          MB_YESNO | MB_ICONWARNING);
 640                         if (ret != IDYES)
 641                             break;
 642                     }
 643                     if (state->ssh2) {
 644                         ret = ssh2_save_userkey(filename, &state->ssh2key,
 645                                                 *passphrase ? passphrase : NULL);
 646                     } else {
 647                         ret = saversakey(filename, &state->key,
 648                                          *passphrase ? passphrase : NULL);
 649                     }
 650                     if (ret <= 0) {
 651                         MessageBox(hwnd, "Unable to save key file",
 652                                    "PuTTYgen Error",
 653                                    MB_OK | MB_ICONERROR);
 654                     }
 655                 }
 656             }
 657             break;
 658           case IDC_LOAD:
 659             state = (struct MainDlgState *)GetWindowLong(hwnd, GWL_USERDATA);
 660             if (!state->generation_thread_exists) {
 661                 char filename[FILENAME_MAX];
 662                 if (prompt_keyfile(hwnd, "Load private key:",
 663                                    filename, 0)) {
 664                     char passphrase[PASSPHRASE_MAXLEN];
 665                     int needs_pass;
 666                     int ver;
 667                     int ret;
 668                     char *comment;
 669                     struct PassphraseProcStruct pps;
 670                     struct RSAKey newkey1;
 671                     struct ssh2_userkey *newkey2;
 672
 673                     ver = keyfile_version(filename);
 674                     if (ver == 0) {
 675                         MessageBox(NULL, "Couldn't load private key.",
 676                                    "PuTTYgen Error", MB_OK | MB_ICONERROR);
 677                         break;
 678                     }
 679
 680                     comment = NULL;
 681                     if (ver == 1)
 682                         needs_pass = rsakey_encrypted(filename, &comment);
 683                     else
 684                         needs_pass = ssh2_userkey_encrypted(filename, &comment);
 685                     pps.passphrase = passphrase;
 686                     pps.comment = comment;
 687                     do {
 688                         if (needs_pass) {
 689                             int dlgret;
 690                             dlgret = DialogBoxParam(hinst,
 691                                                     MAKEINTRESOURCE(210),
 692                                                     NULL, PassphraseProc,
 693                                                     (LPARAM)&pps);
 694                             if (!dlgret) {
 695                                 ret = -2;
 696                                 break;
 697                             }
 698                         } else
 699                             *passphrase = '\0';
 700                         if (ver == 1)
 701                             ret = loadrsakey(filename, &newkey1, passphrase);
 702                         else {
 703                             newkey2 = ssh2_load_userkey(filename, passphrase);
 704                             if (newkey2 == SSH2_WRONG_PASSPHRASE)
 705                                 ret = -1;
 706                             else if (!newkey2)
 707                                 ret = 0;
 708                             else
 709                                 ret = 1;
 710                         }
 711                     } while (ret == -1);
 712                     if (comment) sfree(comment);
 713                     if (ret == 0) {
 714                         MessageBox(NULL, "Couldn't load private key.",
 715                                    "PuTTYgen Error", MB_OK | MB_ICONERROR);
 716                     } else if (ret == 1) {
 717                         EnableWindow(GetDlgItem(hwnd, IDC_GENERATE), 1);
 718                         EnableWindow(GetDlgItem(hwnd, IDC_LOAD), 1);
 719                         EnableWindow(GetDlgItem(hwnd, IDC_SAVE), 1);
 720                         /*
 721                          * Now update the key controls with all the
 722                          * key data.
 723                          */
 724                         {
 725                             SetDlgItemText(hwnd, IDC_PASSPHRASE1EDIT,
 726                                            passphrase);
 727                             SetDlgItemText(hwnd, IDC_PASSPHRASE2EDIT,
 728                                            passphrase);
 729                             if (ver == 1) {
 730                                 char buf[128];
 731                                 char *savecomment;
 732
 733                                 state->ssh2 = FALSE;
 734                                 state->commentptr = &state->key.comment;
 735                                 state->key = newkey1;
 736
 737                                 /*
 738                                  * Set the key fingerprint.
 739                                  */
 740                                 savecomment = state->key.comment;
 741                                 state->key.comment = NULL;
 742                                 rsa_fingerprint(buf, sizeof(buf), &state->key);
 743                                 state->key.comment = savecomment;
 744
 745                                 SetDlgItemText(hwnd, IDC_FINGERPRINT, buf);
 746                                 /*
 747                                  * Construct a decimal representation
 748                                  * of the key, for pasting into
 749                                  * .ssh/authorized_keys on a Unix box.
 750                                  */
 751                                 setupbigedit1(hwnd, IDC_KEYDISPLAY, &state->key);
 752                             } else {
 753                                 char *fp;
 754                                 char *savecomment;
 755
 756                                 state->ssh2 = TRUE;
 757                                 state->commentptr = &state->ssh2key.comment;
 758                                 state->ssh2key = *newkey2;   /* structure copy */
 759                                 sfree(newkey2);
 760
 761                                 savecomment = state->ssh2key.comment;
 762                                 state->ssh2key.comment = NULL;
 763                                 fp = state->
 764                                     ssh2key.alg->fingerprint(state->ssh2key.data);
 765                                 state->ssh2key.comment = savecomment;
 766
 767                                 SetDlgItemText(hwnd, IDC_FINGERPRINT, fp);
 768                                 sfree(fp);
 769
 770                                 setupbigedit2(hwnd, IDC_KEYDISPLAY, &state->ssh2key);
 771                             }
 772                             SetDlgItemText(hwnd, IDC_COMMENTEDIT,
 773                                            *state->commentptr);
 774                         }
 775                         /*
 776                          * Finally, hide the progress bar and show
 777                          * the key data.
 778                          */
 779                         hidemany(hwnd, nokey_ids, TRUE);
 780                         hidemany(hwnd, generating_ids, TRUE);
 781                         hidemany(hwnd, gotkey_ids, FALSE);
 782                         state->key_exists = TRUE;
 783                     }
 784                 }
 785             }
 786             break;
 787         }
 788         return 0;
 789       case WM_DONEKEY:
 790         state = (struct MainDlgState *)GetWindowLong(hwnd, GWL_USERDATA);
 791         state->generation_thread_exists = FALSE;
 792         state->key_exists = TRUE;
 793         SendDlgItemMessage(hwnd, IDC_PROGRESS, PBM_SETPOS, PROGRESSRANGE, 0);
 794         EnableWindow(GetDlgItem(hwnd, IDC_GENERATE), 1);
 795         EnableWindow(GetDlgItem(hwnd, IDC_LOAD), 1);
 796         EnableWindow(GetDlgItem(hwnd, IDC_SAVE), 1);
 797         if (state->ssh2) {
 798             state->ssh2key.data = &state->key;
 799             state->ssh2key.alg = &ssh_rsa;
 800             state->commentptr = &state->ssh2key.comment;
 801         } else {
 802             state->commentptr = &state->key.comment;
 803         }
 804         /*
 805          * Invent a comment for the key. We'll do this by including
 806          * the date in it. This will be so horrifyingly ugly that
 807          * the user will immediately want to change it, which is
 808          * what we want :-)
 809          */
 810         *state->commentptr = smalloc(30);
 811         {
 812             time_t t;
 813             struct tm *tm;
 814             time(&t);
 815             tm = localtime(&t);
 816             strftime(*state->commentptr, 30, "rsa-key-%Y%m%d", tm);
 817         }
 818
 819         /*
 820          * Now update the key controls with all the key data.
 821          */
 822         {
 823             char *savecomment;
 824             /*
 825              * Blank passphrase, initially. This isn't dangerous,
 826              * because we will warn (Are You Sure?) before allowing
 827              * the user to save an unprotected private key.
 828              */
 829             SetDlgItemText(hwnd, IDC_PASSPHRASE1EDIT, "");
 830             SetDlgItemText(hwnd, IDC_PASSPHRASE2EDIT, "");
 831             /*
 832              * Set the comment.
 833              */
 834             SetDlgItemText(hwnd, IDC_COMMENTEDIT, *state->commentptr);
 835             /*
 836              * Set the key fingerprint.
 837              */
 838             savecomment = *state->commentptr;
 839             *state->commentptr = NULL;
 840             if (state->ssh2) {
 841                 char *fp;
 842                 fp = state->ssh2key.alg->fingerprint(state->ssh2key.data);
 843                 SetDlgItemText(hwnd, IDC_FINGERPRINT, fp);
 844                 sfree(fp);
 845             } else {
 846                 char buf[128];
 847                 rsa_fingerprint(buf, sizeof(buf), &state->key);
 848                 SetDlgItemText(hwnd, IDC_FINGERPRINT, buf);
 849             }
 850             *state->commentptr = savecomment;
 851             /*
 852              * Construct a decimal representation of the key, for
 853              * pasting into .ssh/authorized_keys on a Unix box.
 854              */
 855             if (state->ssh2) {
 856                 setupbigedit2(hwnd, IDC_KEYDISPLAY, &state->ssh2key);
 857             } else {
 858                 setupbigedit1(hwnd, IDC_KEYDISPLAY, &state->key);
 859             }
 860         }
 861         /*
 862          * Finally, hide the progress bar and show the key data.
 863          */
 864         hidemany(hwnd, nokey_ids, TRUE);
 865         hidemany(hwnd, generating_ids, TRUE);
 866         hidemany(hwnd, gotkey_ids, FALSE);
 867         break;
 868       case WM_CLOSE:
 869         state = (struct MainDlgState *)GetWindowLong(hwnd, GWL_USERDATA);
 870         sfree(state);
 871         EndDialog(hwnd, 1);
 872         return 0;
 873     }
 874     return 0;
 875 }
 876
 877 int WINAPI WinMain(HINSTANCE inst, HINSTANCE prev, LPSTR cmdline, int show) {
 878     InitCommonControls();
 879     hinst = inst;
 880     random_init();
 881     return DialogBox(hinst, MAKEINTRESOURCE(201), NULL, MainDlgProc) != IDOK;
 882 }