agent/protect-tool.c

   1 /* protect-tool.c - A tool to test the secret key protection
   2  * Copyright (C) 2002, 2003, 2004, 2006 Free Software Foundation, Inc.
   3  *
   4  * This file is part of GnuPG.
   5  *
   6  * GnuPG is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 3 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * GnuPG is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #include <config.h>
  21
  22 #include <stdio.h>
  23 #include <stdlib.h>
  24 #include <stddef.h>
  25 #include <stdarg.h>
  26 #include <string.h>
  27 #include <errno.h>
  28 #include <assert.h>
  29 #include <sys/stat.h>
  30 #include <unistd.h>
  31 #ifdef HAVE_LOCALE_H
  32 #include <locale.h>
  33 #endif
  34 #ifdef HAVE_LANGINFO_CODESET
  35 #include <langinfo.h>
  36 #endif
  37 #ifdef HAVE_DOSISH_SYSTEM
  38 #include <fcntl.h> /* for setmode() */
  39 #endif
  40
  41 #define JNLIB_NEED_LOG_LOGV
  42 #include "agent.h"
  43 #include "minip12.h"
  44 #include "simple-pwquery.h"
  45 #include "i18n.h"
  46 #include "sysutils.h"
  47
  48
  49 enum cmd_and_opt_values
  50 { aNull = 0,
  51   oVerbose        = 'v',
  52   oArmor          = 'a',
  53   oPassphrase     = 'P',
  54
  55   oProtect        = 'p',
  56   oUnprotect      = 'u',
  57
  58   oNoVerbose = 500,
  59   oShadow,
  60   oShowShadowInfo,
  61   oShowKeygrip,
  62   oCanonical,
  63
  64   oP12Import,
  65   oP12Export,
  66   oP12Charset,
  67   oStore,
  68   oForce,
  69   oHaveCert,
  70   oNoFailOnExist,
  71   oHomedir,
  72   oPrompt,
  73   oStatusMsg,
  74
  75 aTest };
  76
  77 struct rsa_secret_key_s
  78   {
  79     gcry_mpi_t n;           /* public modulus */
  80     gcry_mpi_t e;           /* public exponent */
  81     gcry_mpi_t d;           /* exponent */
  82     gcry_mpi_t p;           /* prime  p. */
  83     gcry_mpi_t q;           /* prime  q. */
  84     gcry_mpi_t u;           /* inverse of p mod q. */
  85   };
  86
  87
  88 static const char *opt_homedir;
  89 static int opt_armor;
  90 static int opt_canonical;
  91 static int opt_store;
  92 static int opt_force;
  93 static int opt_no_fail_on_exist;
  94 static int opt_have_cert;
  95 static const char *opt_passphrase;
  96 static char *opt_prompt;
  97 static int opt_status_msg;
  98 static const char *opt_p12_charset;
  99
 100 static char *get_passphrase (int promptno, int opt_check);
 101 static char *get_new_passphrase (int promptno);
 102 static void release_passphrase (char *pw);
 103 static int store_private_key (const unsigned char *grip,
 104                               const void *buffer, size_t length, int force);
 105
 106
 107 static ARGPARSE_OPTS opts[] = {
 108
 109   { 301, NULL, 0, N_("@Options:\n ") },
 110
 111   { oVerbose, "verbose",   0, "verbose" },
 112   { oArmor,   "armor",     0, "write output in advanced format" },
 113   { oCanonical, "canonical", 0, "write output in canonical format" },
 114   { oPassphrase, "passphrase", 2, "|STRING|use passphrase STRING" },
 115   { oProtect, "protect",     256, "protect a private key"},
 116   { oUnprotect, "unprotect", 256, "unprotect a private key"},
 117   { oShadow,  "shadow", 256, "create a shadow entry for a public key"},
 118   { oShowShadowInfo,  "show-shadow-info", 256, "return the shadow info"},
 119   { oShowKeygrip, "show-keygrip", 256, "show the \"keygrip\""},
 120
 121   { oP12Import, "p12-import", 256, "import a pkcs#12 encoded private key"},
 122   { oP12Export, "p12-export", 256, "export a private key pkcs#12 encoded"},
 123   { oP12Charset,"p12-charset", 2,
 124     "|NAME|set charset for a new PKCS#12 passphrase to NAME" },
 125   { oHaveCert, "have-cert", 0,  "certificate to export provided on STDIN"},
 126   { oStore,     "store", 0, "store the created key in the appropriate place"},
 127   { oForce,     "force", 0, "force overwriting"},
 128   { oNoFailOnExist, "no-fail-on-exist", 0, "@" },
 129   { oHomedir, "homedir", 2, "@" },
 130   { oPrompt,  "prompt", 2, "|ESCSTRING|use ESCSTRING as prompt in pinentry"},
 131   { oStatusMsg, "enable-status-msg", 0, "@"},
 132
 133   {0}
 134 };
 135
 136 static const char *
 137 my_strusage (int level)
 138 {
 139   const char *p;
 140   switch (level)
 141     {
 142     case 11: p = "gpg-protect-tool (GnuPG)";
 143       break;
 144     case 13: p = VERSION; break;
 145     case 17: p = PRINTABLE_OS_NAME; break;
 146     case 19: p = _("Please report bugs to <" PACKAGE_BUGREPORT ">.\n");
 147       break;
 148     case 1:
 149     case 40: p =  _("Usage: gpg-protect-tool [options] (-h for help)\n");
 150       break;
 151     case 41: p =  _("Syntax: gpg-protect-tool [options] [args]\n"
 152                     "Secret key maintenance tool\n");
 153     break;
 154
 155     default: p = NULL;
 156     }
 157   return p;
 158 }
 159
 160
 161 /* Include the implementation of map_spwq_error.  */
 162 MAP_SPWQ_ERROR_IMPL
 163
 164 /*  static void */
 165 /*  print_mpi (const char *text, gcry_mpi_t a) */
 166 /*  { */
 167 /*    char *buf; */
 168 /*    void *bufaddr = &buf; */
 169 /*    int rc; */
 170
 171 /*    rc = gcry_mpi_aprint (GCRYMPI_FMT_HEX, bufaddr, NULL, a); */
 172 /*    if (rc) */
 173 /*      log_info ("%s: [error printing number: %s]\n", text, gpg_strerror (rc)); */
 174 /*    else */
 175 /*      { */
 176 /*        log_info ("%s: %s\n", text, buf); */
 177 /*        gcry_free (buf); */
 178 /*      } */
 179 /*  } */
 180
 181
 182 \f
 183 static unsigned char *
 184 make_canonical (const char *fname, const char *buf, size_t buflen)
 185 {
 186   int rc;
 187   size_t erroff, len;
 188   gcry_sexp_t sexp;
 189   unsigned char *result;
 190
 191   rc = gcry_sexp_sscan (&sexp, &erroff, buf, buflen);
 192   if (rc)
 193     {
 194       log_error ("invalid S-Expression in `%s' (off=%u): %s\n",
 195                  fname, (unsigned int)erroff, gpg_strerror (rc));
 196       return NULL;
 197     }
 198   len = gcry_sexp_sprint (sexp, GCRYSEXP_FMT_CANON, NULL, 0);
 199   assert (len);
 200   result = xmalloc (len);
 201   len = gcry_sexp_sprint (sexp, GCRYSEXP_FMT_CANON, result, len);
 202   assert (len);
 203   gcry_sexp_release (sexp);
 204   return result;
 205 }
 206
 207 static char *
 208 make_advanced (const unsigned char *buf, size_t buflen)
 209 {
 210   int rc;
 211   size_t erroff, len;
 212   gcry_sexp_t sexp;
 213   char *result;
 214
 215   rc = gcry_sexp_sscan (&sexp, &erroff, (const char*)buf, buflen);
 216   if (rc)
 217     {
 218       log_error ("invalid canonical S-Expression (off=%u): %s\n",
 219                  (unsigned int)erroff, gpg_strerror (rc));
 220       return NULL;
 221     }
 222   len = gcry_sexp_sprint (sexp, GCRYSEXP_FMT_ADVANCED, NULL, 0);
 223   assert (len);
 224   result = xmalloc (len);
 225   len = gcry_sexp_sprint (sexp, GCRYSEXP_FMT_ADVANCED, result, len);
 226   assert (len);
 227   gcry_sexp_release (sexp);
 228   return result;
 229 }
 230
 231
 232 static char *
 233 read_file (const char *fname, size_t *r_length)
 234 {
 235   FILE *fp;
 236   char *buf;
 237   size_t buflen;
 238
 239   if (!strcmp (fname, "-"))
 240     {
 241       size_t nread, bufsize = 0;
 242
 243       fp = stdin;
 244 #ifdef HAVE_DOSISH_SYSTEM
 245       setmode ( fileno(fp) , O_BINARY );
 246 #endif
 247       buf = NULL;
 248       buflen = 0;
 249 #define NCHUNK 8192
 250       do
 251         {
 252           bufsize += NCHUNK;
 253           if (!buf)
 254             buf = xmalloc (bufsize);
 255           else
 256             buf = xrealloc (buf, bufsize);
 257
 258           nread = fread (buf+buflen, 1, NCHUNK, fp);
 259           if (nread < NCHUNK && ferror (fp))
 260             {
 261               log_error ("error reading `[stdin]': %s\n", strerror (errno));
 262               xfree (buf);
 263               return NULL;
 264             }
 265           buflen += nread;
 266         }
 267       while (nread == NCHUNK);
 268 #undef NCHUNK
 269
 270     }
 271   else
 272     {
 273       struct stat st;
 274
 275       fp = fopen (fname, "rb");
 276       if (!fp)
 277         {
 278           log_error ("can't open `%s': %s\n", fname, strerror (errno));
 279           return NULL;
 280         }
 281
 282       if (fstat (fileno(fp), &st))
 283         {
 284           log_error ("can't stat `%s': %s\n", fname, strerror (errno));
 285           fclose (fp);
 286           return NULL;
 287         }
 288
 289       buflen = st.st_size;
 290       buf = xmalloc (buflen+1);
 291       if (fread (buf, buflen, 1, fp) != 1)
 292         {
 293           log_error ("error reading `%s': %s\n", fname, strerror (errno));
 294           fclose (fp);
 295           xfree (buf);
 296           return NULL;
 297         }
 298       fclose (fp);
 299     }
 300
 301   *r_length = buflen;
 302   return buf;
 303 }
 304
 305
 306 static unsigned char *
 307 read_key (const char *fname)
 308 {
 309   char *buf;
 310   size_t buflen;
 311   unsigned char *key;
 312
 313   buf = read_file (fname, &buflen);
 314   if (!buf)
 315     return NULL;
 316   key = make_canonical (fname, buf, buflen);
 317   xfree (buf);
 318   return key;
 319 }
 320
 321
 322 \f
 323 static void
 324 read_and_protect (const char *fname)
 325 {
 326   int  rc;
 327   unsigned char *key;
 328   unsigned char *result;
 329   size_t resultlen;
 330   char *pw;
 331
 332   key = read_key (fname);
 333   if (!key)
 334     return;
 335
 336   pw = get_passphrase (1, 0);
 337   rc = agent_protect (key, pw, &result, &resultlen);
 338   release_passphrase (pw);
 339   xfree (key);
 340   if (rc)
 341     {
 342       log_error ("protecting the key failed: %s\n", gpg_strerror (rc));
 343       return;
 344     }
 345
 346   if (opt_armor)
 347     {
 348       char *p = make_advanced (result, resultlen);
 349       xfree (result);
 350       if (!p)
 351         return;
 352       result = (unsigned char*)p;
 353       resultlen = strlen (p);
 354     }
 355
 356   fwrite (result, resultlen, 1, stdout);
 357   xfree (result);
 358 }
 359
 360
 361 static void
 362 read_and_unprotect (const char *fname)
 363 {
 364   int  rc;
 365   unsigned char *key;
 366   unsigned char *result;
 367   size_t resultlen;
 368   char *pw;
 369   gnupg_isotime_t protected_at;
 370
 371   key = read_key (fname);
 372   if (!key)
 373     return;
 374
 375   rc = agent_unprotect (key, (pw=get_passphrase (1, 0)),
 376                         protected_at, &result, &resultlen);
 377   release_passphrase (pw);
 378   xfree (key);
 379   if (rc)
 380     {
 381       if (opt_status_msg)
 382         log_info ("[PROTECT-TOOL:] bad-passphrase\n");
 383       log_error ("unprotecting the key failed: %s\n", gpg_strerror (rc));
 384       return;
 385     }
 386   if (opt.verbose)
 387     log_info ("key protection done at %.4s-%.2s-%.2s %.2s:%.2s:%s\n",
 388               protected_at, protected_at+4, protected_at+6,
 389               protected_at+9, protected_at+11, protected_at+13);
 390
 391
 392   if (opt_armor)
 393     {
 394       char *p = make_advanced (result, resultlen);
 395       xfree (result);
 396       if (!p)
 397         return;
 398       result = (unsigned char*)p;
 399       resultlen = strlen (p);
 400     }
 401
 402   fwrite (result, resultlen, 1, stdout);
 403   xfree (result);
 404 }
 405
 406
 407 \f
 408 static void
 409 read_and_shadow (const char *fname)
 410 {
 411   int  rc;
 412   unsigned char *key;
 413   unsigned char *result;
 414   size_t resultlen;
 415   unsigned char dummy_info[] = "(8:313233342:43)";
 416
 417   key = read_key (fname);
 418   if (!key)
 419     return;
 420
 421   rc = agent_shadow_key (key, dummy_info, &result);
 422   xfree (key);
 423   if (rc)
 424     {
 425       log_error ("shadowing the key failed: %s\n", gpg_strerror (rc));
 426       return;
 427     }
 428   resultlen = gcry_sexp_canon_len (result, 0, NULL,NULL);
 429   assert (resultlen);
 430
 431   if (opt_armor)
 432     {
 433       char *p = make_advanced (result, resultlen);
 434       xfree (result);
 435       if (!p)
 436         return;
 437       result = (unsigned char*)p;
 438       resultlen = strlen (p);
 439     }
 440
 441   fwrite (result, resultlen, 1, stdout);
 442   xfree (result);
 443 }
 444
 445 static void
 446 show_shadow_info (const char *fname)
 447 {
 448   int  rc;
 449   unsigned char *key;
 450   const unsigned char *info;
 451   size_t infolen;
 452
 453   key = read_key (fname);
 454   if (!key)
 455     return;
 456
 457   rc = agent_get_shadow_info (key, &info);
 458   xfree (key);
 459   if (rc)
 460     {
 461       log_error ("get_shadow_info failed: %s\n", gpg_strerror (rc));
 462       return;
 463     }
 464   infolen = gcry_sexp_canon_len (info, 0, NULL,NULL);
 465   assert (infolen);
 466
 467   if (opt_armor)
 468     {
 469       char *p = make_advanced (info, infolen);
 470       if (!p)
 471         return;
 472       fwrite (p, strlen (p), 1, stdout);
 473       xfree (p);
 474     }
 475   else
 476     fwrite (info, infolen, 1, stdout);
 477 }
 478
 479
 480 static void
 481 show_file (const char *fname)
 482 {
 483   unsigned char *key;
 484   size_t keylen;
 485   char *p;
 486
 487   key = read_key (fname);
 488   if (!key)
 489     return;
 490
 491   keylen = gcry_sexp_canon_len (key, 0, NULL,NULL);
 492   assert (keylen);
 493
 494   if (opt_canonical)
 495     {
 496       fwrite (key, keylen, 1, stdout);
 497     }
 498   else
 499     {
 500       p = make_advanced (key, keylen);
 501       if (p)
 502         {
 503           fwrite (p, strlen (p), 1, stdout);
 504           xfree (p);
 505         }
 506     }
 507   xfree (key);
 508 }
 509
 510 static void
 511 show_keygrip (const char *fname)
 512 {
 513   unsigned char *key;
 514   gcry_sexp_t private;
 515   unsigned char grip[20];
 516   int i;
 517
 518   key = read_key (fname);
 519   if (!key)
 520     return;
 521
 522   if (gcry_sexp_new (&private, key, 0, 0))
 523     {
 524       log_error ("gcry_sexp_new failed\n");
 525       return;
 526     }
 527   xfree (key);
 528
 529   if (!gcry_pk_get_keygrip (private, grip))
 530     {
 531       log_error ("can't calculate keygrip\n");
 532       return;
 533     }
 534   gcry_sexp_release (private);
 535
 536   for (i=0; i < 20; i++)
 537     printf ("%02X", grip[i]);
 538   putchar ('\n');
 539 }
 540
 541 \f
 542 static int
 543 rsa_key_check (struct rsa_secret_key_s *skey)
 544 {
 545   int err = 0;
 546   gcry_mpi_t t = gcry_mpi_snew (0);
 547   gcry_mpi_t t1 = gcry_mpi_snew (0);
 548   gcry_mpi_t t2 = gcry_mpi_snew (0);
 549   gcry_mpi_t phi = gcry_mpi_snew (0);
 550
 551   /* check that n == p * q */
 552   gcry_mpi_mul (t, skey->p, skey->q);
 553   if (gcry_mpi_cmp( t, skey->n) )
 554     {
 555       log_error ("RSA oops: n != p * q\n");
 556       err++;
 557     }
 558
 559   /* check that p is less than q */
 560   if (gcry_mpi_cmp (skey->p, skey->q) > 0)
 561     {
 562       gcry_mpi_t tmp;
 563
 564       log_info ("swapping secret primes\n");
 565       tmp = gcry_mpi_copy (skey->p);
 566       gcry_mpi_set (skey->p, skey->q);
 567       gcry_mpi_set (skey->q, tmp);
 568       gcry_mpi_release (tmp);
 569       /* and must recompute u of course */
 570       gcry_mpi_invm (skey->u, skey->p, skey->q);
 571     }
 572
 573   /* check that e divides neither p-1 nor q-1 */
 574   gcry_mpi_sub_ui (t, skey->p, 1 );
 575   gcry_mpi_div (NULL, t, t, skey->e, 0);
 576   if (!gcry_mpi_cmp_ui( t, 0) )
 577     {
 578       log_error ("RSA oops: e divides p-1\n");
 579       err++;
 580     }
 581   gcry_mpi_sub_ui (t, skey->q, 1);
 582   gcry_mpi_div (NULL, t, t, skey->e, 0);
 583   if (!gcry_mpi_cmp_ui( t, 0))
 584     {
 585       log_info ( "RSA oops: e divides q-1\n" );
 586       err++;
 587     }
 588
 589   /* check that d is correct. */
 590   gcry_mpi_sub_ui (t1, skey->p, 1);
 591   gcry_mpi_sub_ui (t2, skey->q, 1);
 592   gcry_mpi_mul (phi, t1, t2);
 593   gcry_mpi_invm (t, skey->e, phi);
 594   if (gcry_mpi_cmp (t, skey->d))
 595     { /* no: try universal exponent. */
 596       gcry_mpi_gcd (t, t1, t2);
 597       gcry_mpi_div (t, NULL, phi, t, 0);
 598       gcry_mpi_invm (t, skey->e, t);
 599       if (gcry_mpi_cmp (t, skey->d))
 600         {
 601           log_error ("RSA oops: bad secret exponent\n");
 602           err++;
 603         }
 604     }
 605
 606   /* check for correctness of u */
 607   gcry_mpi_invm (t, skey->p, skey->q);
 608   if (gcry_mpi_cmp (t, skey->u))
 609     {
 610       log_info ( "RSA oops: bad u parameter\n");
 611       err++;
 612     }
 613
 614   if (err)
 615     log_info ("RSA secret key check failed\n");
 616
 617   gcry_mpi_release (t);
 618   gcry_mpi_release (t1);
 619   gcry_mpi_release (t2);
 620   gcry_mpi_release (phi);
 621
 622   return err? -1:0;
 623 }
 624
 625
 626 /* A callback used by p12_parse to return a certificate.  */
 627 static void
 628 import_p12_cert_cb (void *opaque, const unsigned char *cert, size_t certlen)
 629 {
 630   struct b64state state;
 631   gpg_error_t err, err2;
 632
 633   err = b64enc_start (&state, stdout, "CERTIFICATE");
 634   if (!err)
 635     err = b64enc_write (&state, cert, certlen);
 636   err2 = b64enc_finish (&state);
 637   if (!err)
 638     err = err2;
 639   if (err)
 640     log_error ("error writing armored certificate: %s\n", gpg_strerror (err));
 641 }
 642
 643 static void
 644 import_p12_file (const char *fname)
 645 {
 646   char *buf;
 647   unsigned char *result;
 648   size_t buflen, resultlen, buf_off;
 649   int i;
 650   int rc;
 651   gcry_mpi_t *kparms;
 652   struct rsa_secret_key_s sk;
 653   gcry_sexp_t s_key;
 654   unsigned char *key;
 655   unsigned char grip[20];
 656   char *pw;
 657
 658   /* fixme: we should release some stuff on error */
 659
 660   buf = read_file (fname, &buflen);
 661   if (!buf)
 662     return;
 663
 664   /* GnuPG 2.0.4 accidently created binary P12 files with the string
 665      "The passphrase is %s encoded.\n\n" prepended to the ASN.1 data.
 666      We fix that here.  */
 667   if (buflen > 29 && !memcmp (buf, "The passphrase is ", 18))
 668     {
 669       for (buf_off=18; buf_off < buflen && buf[buf_off] != '\n'; buf_off++)
 670         ;
 671       buf_off++;
 672       if (buf_off < buflen && buf[buf_off] == '\n')
 673         buf_off++;
 674     }
 675   else
 676     buf_off = 0;
 677
 678   kparms = p12_parse ((unsigned char*)buf+buf_off, buflen-buf_off,
 679                       (pw=get_passphrase (2, 0)),
 680                       import_p12_cert_cb, NULL);
 681   release_passphrase (pw);
 682   xfree (buf);
 683   if (!kparms)
 684     {
 685       log_error ("error parsing or decrypting the PKCS-12 file\n");
 686       return;
 687     }
 688   for (i=0; kparms[i]; i++)
 689     ;
 690   if (i != 8)
 691     {
 692       log_error ("invalid structure of private key\n");
 693       return;
 694     }
 695
 696
 697 /*    print_mpi ("   n", kparms[0]); */
 698 /*    print_mpi ("   e", kparms[1]); */
 699 /*    print_mpi ("   d", kparms[2]); */
 700 /*    print_mpi ("   p", kparms[3]); */
 701 /*    print_mpi ("   q", kparms[4]); */
 702 /*    print_mpi ("dmp1", kparms[5]); */
 703 /*    print_mpi ("dmq1", kparms[6]); */
 704 /*    print_mpi ("   u", kparms[7]); */
 705
 706   sk.n = kparms[0];
 707   sk.e = kparms[1];
 708   sk.d = kparms[2];
 709   sk.q = kparms[3];
 710   sk.p = kparms[4];
 711   sk.u = kparms[7];
 712   if (rsa_key_check (&sk))
 713     return;
 714 /*    print_mpi ("   n", sk.n); */
 715 /*    print_mpi ("   e", sk.e); */
 716 /*    print_mpi ("   d", sk.d); */
 717 /*    print_mpi ("   p", sk.p); */
 718 /*    print_mpi ("   q", sk.q); */
 719 /*    print_mpi ("   u", sk.u); */
 720
 721   /* Create an S-expresion from the parameters. */
 722   rc = gcry_sexp_build (&s_key, NULL,
 723                         "(private-key(rsa(n%m)(e%m)(d%m)(p%m)(q%m)(u%m)))",
 724                         sk.n, sk.e, sk.d, sk.p, sk.q, sk.u, NULL);
 725   for (i=0; i < 8; i++)
 726     gcry_mpi_release (kparms[i]);
 727   gcry_free (kparms);
 728   if (rc)
 729     {
 730       log_error ("failed to created S-expression from key: %s\n",
 731                  gpg_strerror (rc));
 732       return;
 733     }
 734
 735   /* Compute the keygrip. */
 736   if (!gcry_pk_get_keygrip (s_key, grip))
 737     {
 738       log_error ("can't calculate keygrip\n");
 739       return;
 740     }
 741   log_info ("keygrip: ");
 742   for (i=0; i < 20; i++)
 743     log_printf ("%02X", grip[i]);
 744   log_printf ("\n");
 745
 746   /* Convert to canonical encoding. */
 747   buflen = gcry_sexp_sprint (s_key, GCRYSEXP_FMT_CANON, NULL, 0);
 748   assert (buflen);
 749   key = gcry_xmalloc_secure (buflen);
 750   buflen = gcry_sexp_sprint (s_key, GCRYSEXP_FMT_CANON, key, buflen);
 751   assert (buflen);
 752   gcry_sexp_release (s_key);
 753
 754
 755   rc = agent_protect (key, (pw=get_new_passphrase (4)), &result, &resultlen);
 756   release_passphrase (pw);
 757   xfree (key);
 758   if (rc)
 759     {
 760       log_error ("protecting the key failed: %s\n", gpg_strerror (rc));
 761       return;
 762     }
 763
 764   if (opt_armor)
 765     {
 766       char *p = make_advanced (result, resultlen);
 767       xfree (result);
 768       if (!p)
 769         return;
 770       result = (unsigned char*)p;
 771       resultlen = strlen (p);
 772     }
 773
 774   if (opt_store)
 775     store_private_key (grip, result, resultlen, opt_force);
 776   else
 777     fwrite (result, resultlen, 1, stdout);
 778
 779   xfree (result);
 780 }
 781
 782 \f
 783
 784 static gcry_mpi_t *
 785 sexp_to_kparms (gcry_sexp_t sexp)
 786 {
 787   gcry_sexp_t list, l2;
 788   const char *name;
 789   const char *s;
 790   size_t n;
 791   int i, idx;
 792   const char *elems;
 793   gcry_mpi_t *array;
 794
 795   list = gcry_sexp_find_token (sexp, "private-key", 0 );
 796   if(!list)
 797     return NULL;
 798   l2 = gcry_sexp_cadr (list);
 799   gcry_sexp_release (list);
 800   list = l2;
 801   name = gcry_sexp_nth_data (list, 0, &n);
 802   if(!name || n != 3 || memcmp (name, "rsa", 3))
 803     {
 804       gcry_sexp_release (list);
 805       return NULL;
 806     }
 807
 808   /* Parameter names used with RSA. */
 809   elems = "nedpqu";
 810   array = xcalloc (strlen(elems) + 1, sizeof *array);
 811   for (idx=0, s=elems; *s; s++, idx++ )
 812     {
 813       l2 = gcry_sexp_find_token (list, s, 1);
 814       if (!l2)
 815         {
 816           for (i=0; i<idx; i++)
 817             gcry_mpi_release (array[i]);
 818           xfree (array);
 819           gcry_sexp_release (list);
 820           return NULL; /* required parameter not found */
 821         }
 822       array[idx] = gcry_sexp_nth_mpi (l2, 1, GCRYMPI_FMT_USG);
 823       gcry_sexp_release (l2);
 824       if (!array[idx])
 825         {
 826           for (i=0; i<idx; i++)
 827             gcry_mpi_release (array[i]);
 828           xfree (array);
 829           gcry_sexp_release (list);
 830           return NULL; /* required parameter is invalid */
 831         }
 832     }
 833
 834   gcry_sexp_release (list);
 835   return array;
 836 }
 837
 838
 839 /* Check whether STRING is a KEYGRIP, i.e has the correct length and
 840    does only consist of uppercase hex characters. */
 841 static int
 842 is_keygrip (const char *string)
 843 {
 844   int i;
 845
 846   for(i=0; string[i] && i < 41; i++)
 847     if (!strchr("01234567890ABCDEF", string[i]))
 848       return 0;
 849   return i == 40;
 850 }
 851
 852
 853 static void
 854 export_p12_file (const char *fname)
 855 {
 856   int rc;
 857   gcry_mpi_t kparms[9], *kp;
 858   unsigned char *key;
 859   size_t keylen;
 860   gcry_sexp_t private;
 861   struct rsa_secret_key_s sk;
 862   int i;
 863   unsigned char *cert = NULL;
 864   size_t certlen = 0;
 865   int keytype;
 866   size_t keylen_for_wipe = 0;
 867   char *pw;
 868
 869   if ( is_keygrip (fname) )
 870     {
 871       char hexgrip[40+4+1];
 872       char *p;
 873
 874       assert (strlen(fname) == 40);
 875       strcpy (stpcpy (hexgrip, fname), ".key");
 876
 877       p = make_filename (opt_homedir, GNUPG_PRIVATE_KEYS_DIR, hexgrip, NULL);
 878       key = read_key (p);
 879       xfree (p);
 880     }
 881   else
 882     key = read_key (fname);
 883
 884   if (!key)
 885     return;
 886
 887   keytype = agent_private_key_type (key);
 888   if (keytype == PRIVATE_KEY_PROTECTED)
 889     {
 890       unsigned char *tmpkey;
 891       size_t tmplen;
 892
 893       rc = agent_unprotect (key, (pw=get_passphrase (1, 0)),
 894                             NULL, &tmpkey, &tmplen);
 895       release_passphrase (pw);
 896       if (rc)
 897         {
 898           if (opt_status_msg && gpg_err_code (rc) == GPG_ERR_BAD_PASSPHRASE )
 899             log_info ("[PROTECT-TOOL:] bad-passphrase\n");
 900           log_error ("unprotecting key `%s' failed: %s\n",
 901                      fname, gpg_strerror (rc));
 902           xfree (key);
 903           return;
 904         }
 905       xfree (key);
 906       key = tmpkey;
 907       keylen_for_wipe = tmplen;
 908
 909       keytype = agent_private_key_type (key);
 910     }
 911
 912   if (keytype == PRIVATE_KEY_SHADOWED)
 913     {
 914       log_error ("`%s' is a shadowed private key - can't export it\n", fname);
 915       wipememory (key, keylen_for_wipe);
 916       xfree (key);
 917       return;
 918     }
 919   else if (keytype != PRIVATE_KEY_CLEAR)
 920     {
 921       log_error ("\%s' is not a private key\n", fname);
 922       wipememory (key, keylen_for_wipe);
 923       xfree (key);
 924       return;
 925     }
 926
 927
 928   if (opt_have_cert)
 929     {
 930       cert = (unsigned char*)read_file ("-", &certlen);
 931       if (!cert)
 932         {
 933           wipememory (key, keylen_for_wipe);
 934           xfree (key);
 935           return;
 936         }
 937     }
 938
 939
 940   if (gcry_sexp_new (&private, key, 0, 0))
 941     {
 942       log_error ("gcry_sexp_new failed\n");
 943       wipememory (key, keylen_for_wipe);
 944       xfree (key);
 945       xfree (cert);
 946       return;
 947     }
 948   wipememory (key, keylen_for_wipe);
 949   xfree (key);
 950
 951   kp = sexp_to_kparms (private);
 952   gcry_sexp_release (private);
 953   if (!kp)
 954     {
 955       log_error ("error converting key parameters\n");
 956       xfree (cert);
 957       return;
 958     }
 959   sk.n = kp[0];
 960   sk.e = kp[1];
 961   sk.d = kp[2];
 962   sk.p = kp[3];
 963   sk.q = kp[4];
 964   sk.u = kp[5];
 965   xfree (kp);
 966
 967
 968   kparms[0] = sk.n;
 969   kparms[1] = sk.e;
 970   kparms[2] = sk.d;
 971   kparms[3] = sk.q;
 972   kparms[4] = sk.p;
 973   kparms[5] = gcry_mpi_snew (0);  /* compute d mod (p-1) */
 974   gcry_mpi_sub_ui (kparms[5], kparms[3], 1);
 975   gcry_mpi_mod (kparms[5], sk.d, kparms[5]);
 976   kparms[6] = gcry_mpi_snew (0);  /* compute d mod (q-1) */
 977   gcry_mpi_sub_ui (kparms[6], kparms[4], 1);
 978   gcry_mpi_mod (kparms[6], sk.d, kparms[6]);
 979   kparms[7] = sk.u;
 980   kparms[8] = NULL;
 981
 982   key = p12_build (kparms, cert, certlen,
 983                    (pw=get_new_passphrase (3)), opt_p12_charset, &keylen);
 984   release_passphrase (pw);
 985   xfree (cert);
 986   for (i=0; i < 8; i++)
 987     gcry_mpi_release (kparms[i]);
 988   if (!key)
 989     return;
 990
 991 #ifdef HAVE_DOSISH_SYSTEM
 992   setmode ( fileno (stdout) , O_BINARY );
 993 #endif
 994   fwrite (key, keylen, 1, stdout);
 995   xfree (key);
 996 }
 997
 998
 999
1000 /* Do the percent and plus/space unescaping in place and return the
1001    length of the valid buffer. */
1002 static size_t
1003 percent_plus_unescape (unsigned char *string)
1004 {
1005   unsigned char *p = string;
1006   size_t n = 0;
1007
1008   while (*string)
1009     {
1010       if (*string == '%' && string[1] && string[2])
1011         {
1012           string++;
1013           *p++ = xtoi_2 (string);
1014           n++;
1015           string+= 2;
1016         }
1017       else if (*string == '+')
1018         {
1019           *p++ = ' ';
1020           n++;
1021           string++;
1022         }
1023       else
1024         {
1025           *p++ = *string++;
1026           n++;
1027         }
1028     }
1029
1030   return n;
1031 }
1032
1033 /* Remove percent and plus escaping and make sure that the reuslt is a
1034    string.  This is done in place. Returns STRING. */
1035 static char *
1036 percent_plus_unescape_string (char *string)
1037 {
1038   unsigned char *p = (unsigned char*)string;
1039   size_t n;
1040
1041   n = percent_plus_unescape (p);
1042   p[n] = 0;
1043
1044   return string;
1045 }
1046
1047 \f
1048 int
1049 main (int argc, char **argv )
1050 {
1051   ARGPARSE_ARGS pargs;
1052   int cmd = 0;
1053   const char *fname;
1054
1055   set_strusage (my_strusage);
1056   gcry_control (GCRYCTL_SUSPEND_SECMEM_WARN);
1057   log_set_prefix ("gpg-protect-tool", 1);
1058
1059   /* Make sure that our subsystems are ready.  */
1060   init_common_subsystems ();
1061
1062   i18n_init ();
1063
1064   if (!gcry_check_version (NEED_LIBGCRYPT_VERSION) )
1065     {
1066       log_fatal( _("%s is too old (need %s, have %s)\n"), "libgcrypt",
1067                  NEED_LIBGCRYPT_VERSION, gcry_check_version (NULL) );
1068     }
1069
1070   setup_libgcrypt_logging ();
1071   gcry_control (GCRYCTL_INIT_SECMEM, 16384, 0);
1072
1073
1074   opt_homedir = default_homedir ();
1075
1076
1077   pargs.argc = &argc;
1078   pargs.argv = &argv;
1079   pargs.flags=  1;  /* (do not remove the args) */
1080   while (arg_parse (&pargs, opts) )
1081     {
1082       switch (pargs.r_opt)
1083         {
1084         case oVerbose: opt.verbose++; break;
1085         case oArmor:   opt_armor=1; break;
1086         case oCanonical: opt_canonical=1; break;
1087         case oHomedir: opt_homedir = pargs.r.ret_str; break;
1088
1089         case oProtect: cmd = oProtect; break;
1090         case oUnprotect: cmd = oUnprotect; break;
1091         case oShadow: cmd = oShadow; break;
1092         case oShowShadowInfo: cmd = oShowShadowInfo; break;
1093         case oShowKeygrip: cmd = oShowKeygrip; break;
1094         case oP12Import: cmd = oP12Import; break;
1095         case oP12Export: cmd = oP12Export; break;
1096         case oP12Charset: opt_p12_charset = pargs.r.ret_str; break;
1097
1098         case oPassphrase: opt_passphrase = pargs.r.ret_str; break;
1099         case oStore: opt_store = 1; break;
1100         case oForce: opt_force = 1; break;
1101         case oNoFailOnExist: opt_no_fail_on_exist = 1; break;
1102         case oHaveCert: opt_have_cert = 1; break;
1103         case oPrompt: opt_prompt = pargs.r.ret_str; break;
1104         case oStatusMsg: opt_status_msg = 1; break;
1105
1106         default : pargs.err = 2; break;
1107         }
1108     }
1109   if (log_get_errorcount(0))
1110     exit(2);
1111
1112   fname = "-";
1113   if (argc == 1)
1114     fname = *argv;
1115   else if (argc > 1)
1116     usage (1);
1117
1118   /* Tell simple-pwquery about the the standard socket name.  */
1119   {
1120     char *tmp = make_filename (opt_homedir, "S.gpg-agent", NULL);
1121     simple_pw_set_socket (tmp);
1122     xfree (tmp);
1123   }
1124
1125   if (opt_prompt)
1126     opt_prompt = percent_plus_unescape_string (xstrdup (opt_prompt));
1127
1128   if (cmd == oProtect)
1129     read_and_protect (fname);
1130   else if (cmd == oUnprotect)
1131     read_and_unprotect (fname);
1132   else if (cmd == oShadow)
1133     read_and_shadow (fname);
1134   else if (cmd == oShowShadowInfo)
1135     show_shadow_info (fname);
1136   else if (cmd == oShowKeygrip)
1137     show_keygrip (fname);
1138   else if (cmd == oP12Import)
1139     import_p12_file (fname);
1140   else if (cmd == oP12Export)
1141     export_p12_file (fname);
1142   else
1143     show_file (fname);
1144
1145   agent_exit (0);
1146   return 8; /*NOTREACHED*/
1147 }
1148
1149 void
1150 agent_exit (int rc)
1151 {
1152   rc = rc? rc : log_get_errorcount(0)? 2 : 0;
1153   exit (rc);
1154 }
1155
1156
1157 /* Return the passphrase string and ask the agent if it has not been
1158    set from the command line  PROMPTNO select the prompt to display:
1159      0 = default
1160      1 = taken from the option --prompt
1161      2 = for unprotecting a pkcs#12 object
1162      3 = for protecting a new pkcs#12 object
1163      4 = for protecting an imported pkcs#12 in our system
1164      5 = reenter the passphrase
1165    When adding 100 to the values, a "does not match - try again" error
1166    message is shown.
1167 */
1168 static char *
1169 get_passphrase (int promptno, int opt_check)
1170 {
1171   char *pw;
1172   int err;
1173   const char *desc;
1174   char *orig_codeset;
1175   int error_msgno;
1176
1177   if (opt_passphrase)
1178     return xstrdup (opt_passphrase);
1179
1180   error_msgno = promptno / 100;
1181   promptno %= 100;
1182
1183   orig_codeset = i18n_switchto_utf8 ();
1184
1185   if (promptno == 1 && opt_prompt)
1186     desc = opt_prompt;
1187   else if (promptno == 2)
1188     desc = _("Please enter the passphrase to unprotect the "
1189              "PKCS#12 object.");
1190   else if (promptno == 3)
1191     desc = _("Please enter the passphrase to protect the "
1192              "new PKCS#12 object.");
1193   else if (promptno == 4)
1194     desc = _("Please enter the passphrase to protect the "
1195              "imported object within the GnuPG system.");
1196   else if (promptno == 5)
1197     desc = _("Please re-enter this passphrase");
1198   else
1199     desc = _("Please enter the passphrase or the PIN\n"
1200              "needed to complete this operation.");
1201
1202   pw = simple_pwquery (NULL,
1203                        error_msgno == 1? _("does not match - try again"):NULL,
1204                        _("Passphrase:"), desc, opt_check, &err);
1205   err = map_spwq_error (err);
1206
1207   i18n_switchback (orig_codeset);
1208
1209   if (!pw)
1210     {
1211       if (err)
1212         log_error (_("error while asking for the passphrase: %s\n"),
1213                    gpg_strerror (err));
1214       else
1215         log_info (_("cancelled\n"));
1216       agent_exit (0);
1217     }
1218
1219   return pw;
1220 }
1221
1222
1223 /* Same as get_passphrase but requests it a second time and compares
1224    it to the one entered the first time. */
1225 static char *
1226 get_new_passphrase (int promptno)
1227 {
1228   char *pw;
1229   int i, secondpromptno;
1230
1231   pw = get_passphrase (promptno, 1);
1232   if (!pw)
1233     return NULL; /* Canceled. */
1234   if (!*pw)
1235     return pw;   /* Empty passphrase - no need to ask for repeating it. */
1236
1237   secondpromptno = 5;
1238   for (i=0; i < 3; i++)
1239     {
1240       char *pw2 = get_passphrase (secondpromptno, 0);
1241       if (!pw2)
1242         {
1243           xfree (pw);
1244           return NULL; /* Canceled.  */
1245         }
1246       if (!strcmp (pw, pw2))
1247         {
1248           xfree (pw2);
1249           return pw; /* Okay. */
1250         }
1251       secondpromptno = 105;
1252       xfree (pw2);
1253     }
1254   xfree (pw);
1255   return NULL; /* 3 times repeated wrong - cancel.  */
1256 }
1257
1258
1259
1260 static void
1261 release_passphrase (char *pw)
1262 {
1263   if (pw)
1264     {
1265       wipememory (pw, strlen (pw));
1266       xfree (pw);
1267     }
1268 }
1269
1270 static int
1271 store_private_key (const unsigned char *grip,
1272                    const void *buffer, size_t length, int force)
1273 {
1274   int i;
1275   char *fname;
1276   FILE *fp;
1277   char hexgrip[40+4+1];
1278
1279   for (i=0; i < 20; i++)
1280     sprintf (hexgrip+2*i, "%02X", grip[i]);
1281   strcpy (hexgrip+40, ".key");
1282
1283   fname = make_filename (opt_homedir, GNUPG_PRIVATE_KEYS_DIR, hexgrip, NULL);
1284   if (force)
1285     fp = fopen (fname, "wb");
1286   else
1287     {
1288       if (!access (fname, F_OK))
1289       {
1290         if (opt_status_msg)
1291           log_info ("[PROTECT-TOOL:] secretkey-exists\n");
1292         if (opt_no_fail_on_exist)
1293           log_info ("secret key file `%s' already exists\n", fname);
1294         else
1295           log_error ("secret key file `%s' already exists\n", fname);
1296         xfree (fname);
1297         return opt_no_fail_on_exist? 0 : -1;
1298       }
1299       fp = fopen (fname, "wbx");  /* FIXME: the x is a GNU extension - let
1300                                      configure check whether this actually
1301                                      works */
1302     }
1303
1304   if (!fp)
1305     {
1306       log_error ("can't create `%s': %s\n", fname, strerror (errno));
1307       xfree (fname);
1308       return -1;
1309     }
1310
1311   if (fwrite (buffer, length, 1, fp) != 1)
1312     {
1313       log_error ("error writing `%s': %s\n", fname, strerror (errno));
1314       fclose (fp);
1315       remove (fname);
1316       xfree (fname);
1317       return -1;
1318     }
1319   if ( fclose (fp) )
1320     {
1321       log_error ("error closing `%s': %s\n", fname, strerror (errno));
1322       remove (fname);
1323       xfree (fname);
1324       return -1;
1325     }
1326   log_info ("secret key stored as `%s'\n", fname);
1327
1328   if (opt_status_msg)
1329     log_info ("[PROTECT-TOOL:] secretkey-stored\n");
1330
1331   xfree (fname);
1332   return 0;
1333 }