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 "i18n.h"
  45 #include "get-passphrase.h"
  46 #include "sysutils.h"
  47 #include "estream.h"
  48
  49
  50 enum cmd_and_opt_values
  51 {
  52   aNull = 0,
  53   oVerbose        = 'v',
  54   oArmor          = 'a',
  55   oPassphrase     = 'P',
  56
  57   oProtect        = 'p',
  58   oUnprotect      = 'u',
  59
  60   oNoVerbose = 500,
  61   oShadow,
  62   oShowShadowInfo,
  63   oShowKeygrip,
  64   oCanonical,
  65
  66   oP12Import,
  67   oP12Export,
  68   oP12Charset,
  69   oStore,
  70   oForce,
  71   oHaveCert,
  72   oNoFailOnExist,
  73   oHomedir,
  74   oPrompt,
  75   oStatusMsg,
  76
  77   oAgentProgram
  78 };
  79
  80
  81 struct rsa_secret_key_s
  82 {
  83   gcry_mpi_t n;     /* public modulus */
  84   gcry_mpi_t e;     /* public exponent */
  85   gcry_mpi_t d;     /* exponent */
  86   gcry_mpi_t p;     /* prime  p. */
  87   gcry_mpi_t q;     /* prime  q. */
  88   gcry_mpi_t u;     /* inverse of p mod q. */
  89 };
  90
  91
  92 static const char *opt_homedir;
  93 static int opt_armor;
  94 static int opt_canonical;
  95 static int opt_store;
  96 static int opt_force;
  97 static int opt_no_fail_on_exist;
  98 static int opt_have_cert;
  99 static const char *opt_passphrase;
 100 static char *opt_prompt;
 101 static int opt_status_msg;
 102 static const char *opt_p12_charset;
 103 static const char *opt_agent_program;
 104
 105 static char *get_passphrase (int promptno);
 106 static void release_passphrase (char *pw);
 107 static int store_private_key (const unsigned char *grip,
 108                               const void *buffer, size_t length, int force);
 109
 110
 111 static ARGPARSE_OPTS opts[] = {
 112   ARGPARSE_group (300, N_("@Commands:\n ")),
 113
 114   ARGPARSE_c (oProtect,   "protect",   "protect a private key"),
 115   ARGPARSE_c (oUnprotect, "unprotect", "unprotect a private key"),
 116   ARGPARSE_c (oShadow,    "shadow", "create a shadow entry for a public key"),
 117   ARGPARSE_c (oShowShadowInfo,  "show-shadow-info", "return the shadow info"),
 118   ARGPARSE_c (oShowKeygrip, "show-keygrip", "show the \"keygrip\""),
 119   ARGPARSE_c (oP12Import, "p12-import",
 120               "import a pkcs#12 encoded private key"),
 121   ARGPARSE_c (oP12Export, "p12-export",
 122               "export a private key pkcs#12 encoded"),
 123
 124   ARGPARSE_group (301, N_("@\nOptions:\n ")),
 125
 126   ARGPARSE_s_n (oVerbose, "verbose", "verbose"),
 127   ARGPARSE_s_n (oArmor, "armor", "write output in advanced format"),
 128   ARGPARSE_s_n (oCanonical, "canonical", "write output in canonical format"),
 129
 130   ARGPARSE_s_s (oPassphrase, "passphrase", "|STRING|use passphrase STRING"),
 131   ARGPARSE_s_s (oP12Charset,"p12-charset",
 132                 "|NAME|set charset for a new PKCS#12 passphrase to NAME"),
 133   ARGPARSE_s_n (oHaveCert, "have-cert",
 134                 "certificate to export provided on STDIN"),
 135   ARGPARSE_s_n (oStore,    "store",
 136                 "store the created key in the appropriate place"),
 137   ARGPARSE_s_n (oForce,    "force",
 138                 "force overwriting"),
 139   ARGPARSE_s_n (oNoFailOnExist, "no-fail-on-exist", "@"),
 140   ARGPARSE_s_s (oHomedir, "homedir", "@"),
 141   ARGPARSE_s_s (oPrompt,  "prompt",
 142                 "|ESCSTRING|use ESCSTRING as prompt in pinentry"),
 143   ARGPARSE_s_n (oStatusMsg, "enable-status-msg", "@"),
 144
 145   ARGPARSE_s_s (oAgentProgram, "agent-program", "@"),
 146
 147   ARGPARSE_end ()
 148 };
 149
 150 static const char *
 151 my_strusage (int level)
 152 {
 153   const char *p;
 154   switch (level)
 155     {
 156     case 11: p = "gpg-protect-tool (GnuPG)";
 157       break;
 158     case 13: p = VERSION; break;
 159     case 17: p = PRINTABLE_OS_NAME; break;
 160     case 19: p = _("Please report bugs to <@EMAIL@>.\n"); break;
 161
 162     case 1:
 163     case 40: p =  _("Usage: gpg-protect-tool [options] (-h for help)\n");
 164       break;
 165     case 41: p =  _("Syntax: gpg-protect-tool [options] [args]\n"
 166                     "Secret key maintenance tool\n");
 167     break;
 168
 169     default: p = NULL;
 170     }
 171   return p;
 172 }
 173
 174
 175 /*  static void */
 176 /*  print_mpi (const char *text, gcry_mpi_t a) */
 177 /*  { */
 178 /*    char *buf; */
 179 /*    void *bufaddr = &buf; */
 180 /*    int rc; */
 181
 182 /*    rc = gcry_mpi_aprint (GCRYMPI_FMT_HEX, bufaddr, NULL, a); */
 183 /*    if (rc) */
 184 /*      log_info ("%s: [error printing number: %s]\n", text, gpg_strerror (rc)); */
 185 /*    else */
 186 /*      { */
 187 /*        log_info ("%s: %s\n", text, buf); */
 188 /*        gcry_free (buf); */
 189 /*      } */
 190 /*  } */
 191
 192
 193 \f
 194 static unsigned char *
 195 make_canonical (const char *fname, const char *buf, size_t buflen)
 196 {
 197   int rc;
 198   size_t erroff, len;
 199   gcry_sexp_t sexp;
 200   unsigned char *result;
 201
 202   rc = gcry_sexp_sscan (&sexp, &erroff, buf, buflen);
 203   if (rc)
 204     {
 205       log_error ("invalid S-Expression in `%s' (off=%u): %s\n",
 206                  fname, (unsigned int)erroff, gpg_strerror (rc));
 207       return NULL;
 208     }
 209   len = gcry_sexp_sprint (sexp, GCRYSEXP_FMT_CANON, NULL, 0);
 210   assert (len);
 211   result = xmalloc (len);
 212   len = gcry_sexp_sprint (sexp, GCRYSEXP_FMT_CANON, result, len);
 213   assert (len);
 214   gcry_sexp_release (sexp);
 215   return result;
 216 }
 217
 218 static char *
 219 make_advanced (const unsigned char *buf, size_t buflen)
 220 {
 221   int rc;
 222   size_t erroff, len;
 223   gcry_sexp_t sexp;
 224   char *result;
 225
 226   rc = gcry_sexp_sscan (&sexp, &erroff, (const char*)buf, buflen);
 227   if (rc)
 228     {
 229       log_error ("invalid canonical S-Expression (off=%u): %s\n",
 230                  (unsigned int)erroff, gpg_strerror (rc));
 231       return NULL;
 232     }
 233   len = gcry_sexp_sprint (sexp, GCRYSEXP_FMT_ADVANCED, NULL, 0);
 234   assert (len);
 235   result = xmalloc (len);
 236   len = gcry_sexp_sprint (sexp, GCRYSEXP_FMT_ADVANCED, result, len);
 237   assert (len);
 238   gcry_sexp_release (sexp);
 239   return result;
 240 }
 241
 242
 243 static char *
 244 read_file (const char *fname, size_t *r_length)
 245 {
 246   FILE *fp;
 247   char *buf;
 248   size_t buflen;
 249
 250   if (!strcmp (fname, "-"))
 251     {
 252       size_t nread, bufsize = 0;
 253
 254       fp = stdin;
 255 #ifdef HAVE_DOSISH_SYSTEM
 256       setmode ( fileno(fp) , O_BINARY );
 257 #endif
 258       buf = NULL;
 259       buflen = 0;
 260 #define NCHUNK 8192
 261       do
 262         {
 263           bufsize += NCHUNK;
 264           if (!buf)
 265             buf = xmalloc (bufsize);
 266           else
 267             buf = xrealloc (buf, bufsize);
 268
 269           nread = fread (buf+buflen, 1, NCHUNK, fp);
 270           if (nread < NCHUNK && ferror (fp))
 271             {
 272               log_error ("error reading `[stdin]': %s\n", strerror (errno));
 273               xfree (buf);
 274               return NULL;
 275             }
 276           buflen += nread;
 277         }
 278       while (nread == NCHUNK);
 279 #undef NCHUNK
 280
 281     }
 282   else
 283     {
 284       struct stat st;
 285
 286       fp = fopen (fname, "rb");
 287       if (!fp)
 288         {
 289           log_error ("can't open `%s': %s\n", fname, strerror (errno));
 290           return NULL;
 291         }
 292
 293       if (fstat (fileno(fp), &st))
 294         {
 295           log_error ("can't stat `%s': %s\n", fname, strerror (errno));
 296           fclose (fp);
 297           return NULL;
 298         }
 299
 300       buflen = st.st_size;
 301       buf = xmalloc (buflen+1);
 302       if (fread (buf, buflen, 1, fp) != 1)
 303         {
 304           log_error ("error reading `%s': %s\n", fname, strerror (errno));
 305           fclose (fp);
 306           xfree (buf);
 307           return NULL;
 308         }
 309       fclose (fp);
 310     }
 311
 312   *r_length = buflen;
 313   return buf;
 314 }
 315
 316
 317 static unsigned char *
 318 read_key (const char *fname)
 319 {
 320   char *buf;
 321   size_t buflen;
 322   unsigned char *key;
 323
 324   buf = read_file (fname, &buflen);
 325   if (!buf)
 326     return NULL;
 327   key = make_canonical (fname, buf, buflen);
 328   xfree (buf);
 329   return key;
 330 }
 331
 332
 333 \f
 334 static void
 335 read_and_protect (const char *fname)
 336 {
 337   int  rc;
 338   unsigned char *key;
 339   unsigned char *result;
 340   size_t resultlen;
 341   char *pw;
 342
 343   key = read_key (fname);
 344   if (!key)
 345     return;
 346
 347   pw = get_passphrase (1);
 348   rc = agent_protect (key, pw, &result, &resultlen);
 349   release_passphrase (pw);
 350   xfree (key);
 351   if (rc)
 352     {
 353       log_error ("protecting the key failed: %s\n", gpg_strerror (rc));
 354       return;
 355     }
 356
 357   if (opt_armor)
 358     {
 359       char *p = make_advanced (result, resultlen);
 360       xfree (result);
 361       if (!p)
 362         return;
 363       result = (unsigned char*)p;
 364       resultlen = strlen (p);
 365     }
 366
 367   fwrite (result, resultlen, 1, stdout);
 368   xfree (result);
 369 }
 370
 371
 372 static void
 373 read_and_unprotect (const char *fname)
 374 {
 375   int  rc;
 376   unsigned char *key;
 377   unsigned char *result;
 378   size_t resultlen;
 379   char *pw;
 380   gnupg_isotime_t protected_at;
 381
 382   key = read_key (fname);
 383   if (!key)
 384     return;
 385
 386   rc = agent_unprotect (key, (pw=get_passphrase (1)),
 387                         protected_at, &result, &resultlen);
 388   release_passphrase (pw);
 389   xfree (key);
 390   if (rc)
 391     {
 392       if (opt_status_msg)
 393         log_info ("[PROTECT-TOOL:] bad-passphrase\n");
 394       log_error ("unprotecting the key failed: %s\n", gpg_strerror (rc));
 395       return;
 396     }
 397   if (opt.verbose)
 398     log_info ("key protection done at %.4s-%.2s-%.2s %.2s:%.2s:%s\n",
 399               protected_at, protected_at+4, protected_at+6,
 400               protected_at+9, protected_at+11, protected_at+13);
 401
 402
 403   if (opt_armor)
 404     {
 405       char *p = make_advanced (result, resultlen);
 406       xfree (result);
 407       if (!p)
 408         return;
 409       result = (unsigned char*)p;
 410       resultlen = strlen (p);
 411     }
 412
 413   fwrite (result, resultlen, 1, stdout);
 414   xfree (result);
 415 }
 416
 417
 418 \f
 419 static void
 420 read_and_shadow (const char *fname)
 421 {
 422   int  rc;
 423   unsigned char *key;
 424   unsigned char *result;
 425   size_t resultlen;
 426   unsigned char dummy_info[] = "(8:313233342:43)";
 427
 428   key = read_key (fname);
 429   if (!key)
 430     return;
 431
 432   rc = agent_shadow_key (key, dummy_info, &result);
 433   xfree (key);
 434   if (rc)
 435     {
 436       log_error ("shadowing the key failed: %s\n", gpg_strerror (rc));
 437       return;
 438     }
 439   resultlen = gcry_sexp_canon_len (result, 0, NULL,NULL);
 440   assert (resultlen);
 441
 442   if (opt_armor)
 443     {
 444       char *p = make_advanced (result, resultlen);
 445       xfree (result);
 446       if (!p)
 447         return;
 448       result = (unsigned char*)p;
 449       resultlen = strlen (p);
 450     }
 451
 452   fwrite (result, resultlen, 1, stdout);
 453   xfree (result);
 454 }
 455
 456 static void
 457 show_shadow_info (const char *fname)
 458 {
 459   int  rc;
 460   unsigned char *key;
 461   const unsigned char *info;
 462   size_t infolen;
 463
 464   key = read_key (fname);
 465   if (!key)
 466     return;
 467
 468   rc = agent_get_shadow_info (key, &info);
 469   xfree (key);
 470   if (rc)
 471     {
 472       log_error ("get_shadow_info failed: %s\n", gpg_strerror (rc));
 473       return;
 474     }
 475   infolen = gcry_sexp_canon_len (info, 0, NULL,NULL);
 476   assert (infolen);
 477
 478   if (opt_armor)
 479     {
 480       char *p = make_advanced (info, infolen);
 481       if (!p)
 482         return;
 483       fwrite (p, strlen (p), 1, stdout);
 484       xfree (p);
 485     }
 486   else
 487     fwrite (info, infolen, 1, stdout);
 488 }
 489
 490
 491 static void
 492 show_file (const char *fname)
 493 {
 494   unsigned char *key;
 495   size_t keylen;
 496   char *p;
 497
 498   key = read_key (fname);
 499   if (!key)
 500     return;
 501
 502   keylen = gcry_sexp_canon_len (key, 0, NULL,NULL);
 503   assert (keylen);
 504
 505   if (opt_canonical)
 506     {
 507       fwrite (key, keylen, 1, stdout);
 508     }
 509   else
 510     {
 511       p = make_advanced (key, keylen);
 512       if (p)
 513         {
 514           fwrite (p, strlen (p), 1, stdout);
 515           xfree (p);
 516         }
 517     }
 518   xfree (key);
 519 }
 520
 521 static void
 522 show_keygrip (const char *fname)
 523 {
 524   unsigned char *key;
 525   gcry_sexp_t private;
 526   unsigned char grip[20];
 527   int i;
 528
 529   key = read_key (fname);
 530   if (!key)
 531     return;
 532
 533   if (gcry_sexp_new (&private, key, 0, 0))
 534     {
 535       log_error ("gcry_sexp_new failed\n");
 536       return;
 537     }
 538   xfree (key);
 539
 540   if (!gcry_pk_get_keygrip (private, grip))
 541     {
 542       log_error ("can't calculate keygrip\n");
 543       return;
 544     }
 545   gcry_sexp_release (private);
 546
 547   for (i=0; i < 20; i++)
 548     printf ("%02X", grip[i]);
 549   putchar ('\n');
 550 }
 551
 552 \f
 553 static int
 554 rsa_key_check (struct rsa_secret_key_s *skey)
 555 {
 556   int err = 0;
 557   gcry_mpi_t t = gcry_mpi_snew (0);
 558   gcry_mpi_t t1 = gcry_mpi_snew (0);
 559   gcry_mpi_t t2 = gcry_mpi_snew (0);
 560   gcry_mpi_t phi = gcry_mpi_snew (0);
 561
 562   /* check that n == p * q */
 563   gcry_mpi_mul (t, skey->p, skey->q);
 564   if (gcry_mpi_cmp( t, skey->n) )
 565     {
 566       log_error ("RSA oops: n != p * q\n");
 567       err++;
 568     }
 569
 570   /* check that p is less than q */
 571   if (gcry_mpi_cmp (skey->p, skey->q) > 0)
 572     {
 573       gcry_mpi_t tmp;
 574
 575       log_info ("swapping secret primes\n");
 576       tmp = gcry_mpi_copy (skey->p);
 577       gcry_mpi_set (skey->p, skey->q);
 578       gcry_mpi_set (skey->q, tmp);
 579       gcry_mpi_release (tmp);
 580       /* and must recompute u of course */
 581       gcry_mpi_invm (skey->u, skey->p, skey->q);
 582     }
 583
 584   /* check that e divides neither p-1 nor q-1 */
 585   gcry_mpi_sub_ui (t, skey->p, 1 );
 586   gcry_mpi_div (NULL, t, t, skey->e, 0);
 587   if (!gcry_mpi_cmp_ui( t, 0) )
 588     {
 589       log_error ("RSA oops: e divides p-1\n");
 590       err++;
 591     }
 592   gcry_mpi_sub_ui (t, skey->q, 1);
 593   gcry_mpi_div (NULL, t, t, skey->e, 0);
 594   if (!gcry_mpi_cmp_ui( t, 0))
 595     {
 596       log_info ( "RSA oops: e divides q-1\n" );
 597       err++;
 598     }
 599
 600   /* check that d is correct. */
 601   gcry_mpi_sub_ui (t1, skey->p, 1);
 602   gcry_mpi_sub_ui (t2, skey->q, 1);
 603   gcry_mpi_mul (phi, t1, t2);
 604   gcry_mpi_invm (t, skey->e, phi);
 605   if (gcry_mpi_cmp (t, skey->d))
 606     { /* no: try universal exponent. */
 607       gcry_mpi_gcd (t, t1, t2);
 608       gcry_mpi_div (t, NULL, phi, t, 0);
 609       gcry_mpi_invm (t, skey->e, t);
 610       if (gcry_mpi_cmp (t, skey->d))
 611         {
 612           log_error ("RSA oops: bad secret exponent\n");
 613           err++;
 614         }
 615     }
 616
 617   /* check for correctness of u */
 618   gcry_mpi_invm (t, skey->p, skey->q);
 619   if (gcry_mpi_cmp (t, skey->u))
 620     {
 621       log_info ( "RSA oops: bad u parameter\n");
 622       err++;
 623     }
 624
 625   if (err)
 626     log_info ("RSA secret key check failed\n");
 627
 628   gcry_mpi_release (t);
 629   gcry_mpi_release (t1);
 630   gcry_mpi_release (t2);
 631   gcry_mpi_release (phi);
 632
 633   return err? -1:0;
 634 }
 635
 636
 637 /* A callback used by p12_parse to return a certificate.  */
 638 static void
 639 import_p12_cert_cb (void *opaque, const unsigned char *cert, size_t certlen)
 640 {
 641   struct b64state state;
 642   gpg_error_t err, err2;
 643
 644   (void)opaque;
 645
 646   err = b64enc_start (&state, stdout, "CERTIFICATE");
 647   if (!err)
 648     err = b64enc_write (&state, cert, certlen);
 649   err2 = b64enc_finish (&state);
 650   if (!err)
 651     err = err2;
 652   if (err)
 653     log_error ("error writing armored certificate: %s\n", gpg_strerror (err));
 654 }
 655
 656 static void
 657 import_p12_file (const char *fname)
 658 {
 659   char *buf;
 660   unsigned char *result;
 661   size_t buflen, resultlen, buf_off;
 662   int i;
 663   int rc;
 664   gcry_mpi_t *kparms;
 665   struct rsa_secret_key_s sk;
 666   gcry_sexp_t s_key;
 667   unsigned char *key;
 668   unsigned char grip[20];
 669   char *pw;
 670
 671   /* fixme: we should release some stuff on error */
 672
 673   buf = read_file (fname, &buflen);
 674   if (!buf)
 675     return;
 676
 677   /* GnuPG 2.0.4 accidently created binary P12 files with the string
 678      "The passphrase is %s encoded.\n\n" prepended to the ASN.1 data.
 679      We fix that here.  */
 680   if (buflen > 29 && !memcmp (buf, "The passphrase is ", 18))
 681     {
 682       for (buf_off=18; buf_off < buflen && buf[buf_off] != '\n'; buf_off++)
 683         ;
 684       buf_off++;
 685       if (buf_off < buflen && buf[buf_off] == '\n')
 686         buf_off++;
 687     }
 688   else
 689     buf_off = 0;
 690
 691   kparms = p12_parse ((unsigned char*)buf+buf_off, buflen-buf_off,
 692                       (pw=get_passphrase (2)),
 693                       import_p12_cert_cb, NULL);
 694   release_passphrase (pw);
 695   xfree (buf);
 696   if (!kparms)
 697     {
 698       log_error ("error parsing or decrypting the PKCS-12 file\n");
 699       return;
 700     }
 701   for (i=0; kparms[i]; i++)
 702     ;
 703   if (i != 8)
 704     {
 705       log_error ("invalid structure of private key\n");
 706       return;
 707     }
 708
 709
 710 /*    print_mpi ("   n", kparms[0]); */
 711 /*    print_mpi ("   e", kparms[1]); */
 712 /*    print_mpi ("   d", kparms[2]); */
 713 /*    print_mpi ("   p", kparms[3]); */
 714 /*    print_mpi ("   q", kparms[4]); */
 715 /*    print_mpi ("dmp1", kparms[5]); */
 716 /*    print_mpi ("dmq1", kparms[6]); */
 717 /*    print_mpi ("   u", kparms[7]); */
 718
 719   sk.n = kparms[0];
 720   sk.e = kparms[1];
 721   sk.d = kparms[2];
 722   sk.q = kparms[3];
 723   sk.p = kparms[4];
 724   sk.u = kparms[7];
 725   if (rsa_key_check (&sk))
 726     return;
 727 /*    print_mpi ("   n", sk.n); */
 728 /*    print_mpi ("   e", sk.e); */
 729 /*    print_mpi ("   d", sk.d); */
 730 /*    print_mpi ("   p", sk.p); */
 731 /*    print_mpi ("   q", sk.q); */
 732 /*    print_mpi ("   u", sk.u); */
 733
 734   /* Create an S-expresion from the parameters. */
 735   rc = gcry_sexp_build (&s_key, NULL,
 736                         "(private-key(rsa(n%m)(e%m)(d%m)(p%m)(q%m)(u%m)))",
 737                         sk.n, sk.e, sk.d, sk.p, sk.q, sk.u, NULL);
 738   for (i=0; i < 8; i++)
 739     gcry_mpi_release (kparms[i]);
 740   gcry_free (kparms);
 741   if (rc)
 742     {
 743       log_error ("failed to created S-expression from key: %s\n",
 744                  gpg_strerror (rc));
 745       return;
 746     }
 747
 748   /* Compute the keygrip. */
 749   if (!gcry_pk_get_keygrip (s_key, grip))
 750     {
 751       log_error ("can't calculate keygrip\n");
 752       return;
 753     }
 754   log_info ("keygrip: ");
 755   for (i=0; i < 20; i++)
 756     log_printf ("%02X", grip[i]);
 757   log_printf ("\n");
 758
 759   /* Convert to canonical encoding. */
 760   buflen = gcry_sexp_sprint (s_key, GCRYSEXP_FMT_CANON, NULL, 0);
 761   assert (buflen);
 762   key = gcry_xmalloc_secure (buflen);
 763   buflen = gcry_sexp_sprint (s_key, GCRYSEXP_FMT_CANON, key, buflen);
 764   assert (buflen);
 765   gcry_sexp_release (s_key);
 766
 767   pw = get_passphrase (4);
 768   rc = agent_protect (key, pw, &result, &resultlen);
 769   release_passphrase (pw);
 770   xfree (key);
 771   if (rc)
 772     {
 773       log_error ("protecting the key failed: %s\n", gpg_strerror (rc));
 774       return;
 775     }
 776
 777   if (opt_armor)
 778     {
 779       char *p = make_advanced (result, resultlen);
 780       xfree (result);
 781       if (!p)
 782         return;
 783       result = (unsigned char*)p;
 784       resultlen = strlen (p);
 785     }
 786
 787   if (opt_store)
 788     store_private_key (grip, result, resultlen, opt_force);
 789   else
 790     fwrite (result, resultlen, 1, stdout);
 791
 792   xfree (result);
 793 }
 794
 795 \f
 796
 797 static gcry_mpi_t *
 798 sexp_to_kparms (gcry_sexp_t sexp)
 799 {
 800   gcry_sexp_t list, l2;
 801   const char *name;
 802   const char *s;
 803   size_t n;
 804   int i, idx;
 805   const char *elems;
 806   gcry_mpi_t *array;
 807
 808   list = gcry_sexp_find_token (sexp, "private-key", 0 );
 809   if(!list)
 810     return NULL;
 811   l2 = gcry_sexp_cadr (list);
 812   gcry_sexp_release (list);
 813   list = l2;
 814   name = gcry_sexp_nth_data (list, 0, &n);
 815   if(!name || n != 3 || memcmp (name, "rsa", 3))
 816     {
 817       gcry_sexp_release (list);
 818       return NULL;
 819     }
 820
 821   /* Parameter names used with RSA. */
 822   elems = "nedpqu";
 823   array = xcalloc (strlen(elems) + 1, sizeof *array);
 824   for (idx=0, s=elems; *s; s++, idx++ )
 825     {
 826       l2 = gcry_sexp_find_token (list, s, 1);
 827       if (!l2)
 828         {
 829           for (i=0; i<idx; i++)
 830             gcry_mpi_release (array[i]);
 831           xfree (array);
 832           gcry_sexp_release (list);
 833           return NULL; /* required parameter not found */
 834         }
 835       array[idx] = gcry_sexp_nth_mpi (l2, 1, GCRYMPI_FMT_USG);
 836       gcry_sexp_release (l2);
 837       if (!array[idx])
 838         {
 839           for (i=0; i<idx; i++)
 840             gcry_mpi_release (array[i]);
 841           xfree (array);
 842           gcry_sexp_release (list);
 843           return NULL; /* required parameter is invalid */
 844         }
 845     }
 846
 847   gcry_sexp_release (list);
 848   return array;
 849 }
 850
 851
 852 /* Check whether STRING is a KEYGRIP, i.e has the correct length and
 853    does only consist of uppercase hex characters. */
 854 static int
 855 is_keygrip (const char *string)
 856 {
 857   int i;
 858
 859   for(i=0; string[i] && i < 41; i++)
 860     if (!strchr("01234567890ABCDEF", string[i]))
 861       return 0;
 862   return i == 40;
 863 }
 864
 865
 866 static void
 867 export_p12_file (const char *fname)
 868 {
 869   int rc;
 870   gcry_mpi_t kparms[9], *kp;
 871   unsigned char *key;
 872   size_t keylen;
 873   gcry_sexp_t private;
 874   struct rsa_secret_key_s sk;
 875   int i;
 876   unsigned char *cert = NULL;
 877   size_t certlen = 0;
 878   int keytype;
 879   size_t keylen_for_wipe = 0;
 880   char *pw;
 881
 882   if ( is_keygrip (fname) )
 883     {
 884       char hexgrip[40+4+1];
 885       char *p;
 886
 887       assert (strlen(fname) == 40);
 888       strcpy (stpcpy (hexgrip, fname), ".key");
 889
 890       p = make_filename (opt_homedir, GNUPG_PRIVATE_KEYS_DIR, hexgrip, NULL);
 891       key = read_key (p);
 892       xfree (p);
 893     }
 894   else
 895     key = read_key (fname);
 896
 897   if (!key)
 898     return;
 899
 900   keytype = agent_private_key_type (key);
 901   if (keytype == PRIVATE_KEY_PROTECTED)
 902     {
 903       unsigned char *tmpkey;
 904       size_t tmplen;
 905
 906       rc = agent_unprotect (key, (pw=get_passphrase (1)),
 907                             NULL, &tmpkey, &tmplen);
 908       release_passphrase (pw);
 909       if (rc)
 910         {
 911           if (opt_status_msg && gpg_err_code (rc) == GPG_ERR_BAD_PASSPHRASE )
 912             log_info ("[PROTECT-TOOL:] bad-passphrase\n");
 913           log_error ("unprotecting key `%s' failed: %s\n",
 914                      fname, gpg_strerror (rc));
 915           xfree (key);
 916           return;
 917         }
 918       xfree (key);
 919       key = tmpkey;
 920       keylen_for_wipe = tmplen;
 921
 922       keytype = agent_private_key_type (key);
 923     }
 924
 925   if (keytype == PRIVATE_KEY_SHADOWED)
 926     {
 927       log_error ("`%s' is a shadowed private key - can't export it\n", fname);
 928       wipememory (key, keylen_for_wipe);
 929       xfree (key);
 930       return;
 931     }
 932   else if (keytype != PRIVATE_KEY_CLEAR)
 933     {
 934       log_error ("\%s' is not a private key\n", fname);
 935       wipememory (key, keylen_for_wipe);
 936       xfree (key);
 937       return;
 938     }
 939
 940
 941   if (opt_have_cert)
 942     {
 943       cert = (unsigned char*)read_file ("-", &certlen);
 944       if (!cert)
 945         {
 946           wipememory (key, keylen_for_wipe);
 947           xfree (key);
 948           return;
 949         }
 950     }
 951
 952
 953   if (gcry_sexp_new (&private, key, 0, 0))
 954     {
 955       log_error ("gcry_sexp_new failed\n");
 956       wipememory (key, keylen_for_wipe);
 957       xfree (key);
 958       xfree (cert);
 959       return;
 960     }
 961   wipememory (key, keylen_for_wipe);
 962   xfree (key);
 963
 964   kp = sexp_to_kparms (private);
 965   gcry_sexp_release (private);
 966   if (!kp)
 967     {
 968       log_error ("error converting key parameters\n");
 969       xfree (cert);
 970       return;
 971     }
 972   sk.n = kp[0];
 973   sk.e = kp[1];
 974   sk.d = kp[2];
 975   sk.p = kp[3];
 976   sk.q = kp[4];
 977   sk.u = kp[5];
 978   xfree (kp);
 979
 980
 981   kparms[0] = sk.n;
 982   kparms[1] = sk.e;
 983   kparms[2] = sk.d;
 984   kparms[3] = sk.q;
 985   kparms[4] = sk.p;
 986   kparms[5] = gcry_mpi_snew (0);  /* compute d mod (p-1) */
 987   gcry_mpi_sub_ui (kparms[5], kparms[3], 1);
 988   gcry_mpi_mod (kparms[5], sk.d, kparms[5]);
 989   kparms[6] = gcry_mpi_snew (0);  /* compute d mod (q-1) */
 990   gcry_mpi_sub_ui (kparms[6], kparms[4], 1);
 991   gcry_mpi_mod (kparms[6], sk.d, kparms[6]);
 992   kparms[7] = sk.u;
 993   kparms[8] = NULL;
 994
 995   pw = get_passphrase (3);
 996   key = p12_build (kparms, cert, certlen, pw, opt_p12_charset, &keylen);
 997   release_passphrase (pw);
 998   xfree (cert);
 999   for (i=0; i < 8; i++)
1000     gcry_mpi_release (kparms[i]);
1001   if (!key)
1002     return;
1003
1004 #ifdef HAVE_DOSISH_SYSTEM
1005   setmode ( fileno (stdout) , O_BINARY );
1006 #endif
1007   fwrite (key, keylen, 1, stdout);
1008   xfree (key);
1009 }
1010
1011
1012 \f
1013 int
1014 main (int argc, char **argv )
1015 {
1016   ARGPARSE_ARGS pargs;
1017   int cmd = 0;
1018   const char *fname;
1019
1020   set_strusage (my_strusage);
1021   gcry_control (GCRYCTL_SUSPEND_SECMEM_WARN);
1022   log_set_prefix ("gpg-protect-tool", 1);
1023
1024   /* Make sure that our subsystems are ready.  */
1025   i18n_init ();
1026   init_common_subsystems ();
1027
1028   if (!gcry_check_version (NEED_LIBGCRYPT_VERSION) )
1029     {
1030       log_fatal( _("%s is too old (need %s, have %s)\n"), "libgcrypt",
1031                  NEED_LIBGCRYPT_VERSION, gcry_check_version (NULL) );
1032     }
1033
1034   setup_libgcrypt_logging ();
1035   gcry_control (GCRYCTL_INIT_SECMEM, 16384, 0);
1036
1037
1038   opt_homedir = default_homedir ();
1039
1040
1041   pargs.argc = &argc;
1042   pargs.argv = &argv;
1043   pargs.flags=  1;  /* (do not remove the args) */
1044   while (arg_parse (&pargs, opts) )
1045     {
1046       switch (pargs.r_opt)
1047         {
1048         case oVerbose: opt.verbose++; break;
1049         case oArmor:   opt_armor=1; break;
1050         case oCanonical: opt_canonical=1; break;
1051         case oHomedir: opt_homedir = pargs.r.ret_str; break;
1052
1053         case oAgentProgram: opt_agent_program = pargs.r.ret_str; break;
1054
1055         case oProtect: cmd = oProtect; break;
1056         case oUnprotect: cmd = oUnprotect; break;
1057         case oShadow: cmd = oShadow; break;
1058         case oShowShadowInfo: cmd = oShowShadowInfo; break;
1059         case oShowKeygrip: cmd = oShowKeygrip; break;
1060         case oP12Import: cmd = oP12Import; break;
1061         case oP12Export: cmd = oP12Export; break;
1062         case oP12Charset: opt_p12_charset = pargs.r.ret_str; break;
1063
1064         case oPassphrase: opt_passphrase = pargs.r.ret_str; break;
1065         case oStore: opt_store = 1; break;
1066         case oForce: opt_force = 1; break;
1067         case oNoFailOnExist: opt_no_fail_on_exist = 1; break;
1068         case oHaveCert: opt_have_cert = 1; break;
1069         case oPrompt: opt_prompt = pargs.r.ret_str; break;
1070         case oStatusMsg: opt_status_msg = 1; break;
1071
1072         default: pargs.err = ARGPARSE_PRINT_ERROR; break;
1073         }
1074     }
1075   if (log_get_errorcount (0))
1076     exit (2);
1077
1078   fname = "-";
1079   if (argc == 1)
1080     fname = *argv;
1081   else if (argc > 1)
1082     usage (1);
1083
1084   /* Set the information which can't be taken from envvars.  */
1085   gnupg_prepare_get_passphrase (GPG_ERR_SOURCE_DEFAULT,
1086                                 opt.verbose,
1087                                 opt_homedir,
1088                                 opt_agent_program,
1089                                 NULL, NULL, NULL);
1090
1091   if (opt_prompt)
1092     opt_prompt = percent_plus_unescape (opt_prompt, 0);
1093
1094   if (cmd == oProtect)
1095     read_and_protect (fname);
1096   else if (cmd == oUnprotect)
1097     read_and_unprotect (fname);
1098   else if (cmd == oShadow)
1099     read_and_shadow (fname);
1100   else if (cmd == oShowShadowInfo)
1101     show_shadow_info (fname);
1102   else if (cmd == oShowKeygrip)
1103     show_keygrip (fname);
1104   else if (cmd == oP12Import)
1105     import_p12_file (fname);
1106   else if (cmd == oP12Export)
1107     export_p12_file (fname);
1108   else
1109     show_file (fname);
1110
1111   agent_exit (0);
1112   return 8; /*NOTREACHED*/
1113 }
1114
1115 void
1116 agent_exit (int rc)
1117 {
1118   rc = rc? rc : log_get_errorcount(0)? 2 : 0;
1119   exit (rc);
1120 }
1121
1122
1123 /* Return the passphrase string and ask the agent if it has not been
1124    set from the command line  PROMPTNO select the prompt to display:
1125      0 = default
1126      1 = taken from the option --prompt
1127      2 = for unprotecting a pkcs#12 object
1128      3 = for protecting a new pkcs#12 object
1129      4 = for protecting an imported pkcs#12 in our system
1130 */
1131 static char *
1132 get_passphrase (int promptno)
1133 {
1134   char *pw;
1135   int err;
1136   const char *desc;
1137   char *orig_codeset;
1138   int repeat = 0;
1139
1140   if (opt_passphrase)
1141     return xstrdup (opt_passphrase);
1142
1143   orig_codeset = i18n_switchto_utf8 ();
1144
1145   if (promptno == 1 && opt_prompt)
1146     {
1147       desc = opt_prompt;
1148     }
1149   else if (promptno == 2)
1150     {
1151       desc = _("Please enter the passphrase to unprotect the "
1152                "PKCS#12 object.");
1153     }
1154   else if (promptno == 3)
1155     {
1156       desc = _("Please enter the passphrase to protect the "
1157                "new PKCS#12 object.");
1158       repeat = 1;
1159     }
1160   else if (promptno == 4)
1161     {
1162       desc = _("Please enter the passphrase to protect the "
1163                "imported object within the GnuPG system.");
1164       repeat = 1;
1165     }
1166   else
1167     desc = _("Please enter the passphrase or the PIN\n"
1168              "needed to complete this operation.");
1169
1170   i18n_switchback (orig_codeset);
1171
1172   err = gnupg_get_passphrase (NULL, NULL, _("Passphrase:"), desc,
1173                               repeat, repeat, 1, &pw);
1174   if (err)
1175     {
1176       if (gpg_err_code (err) == GPG_ERR_CANCELED)
1177         log_info (_("cancelled\n"));
1178       else
1179         log_error (_("error while asking for the passphrase: %s\n"),
1180                    gpg_strerror (err));
1181       agent_exit (0);
1182     }
1183   assert (pw);
1184
1185   return pw;
1186 }
1187
1188
1189 static void
1190 release_passphrase (char *pw)
1191 {
1192   if (pw)
1193     {
1194       wipememory (pw, strlen (pw));
1195       xfree (pw);
1196     }
1197 }
1198
1199 static int
1200 store_private_key (const unsigned char *grip,
1201                    const void *buffer, size_t length, int force)
1202 {
1203   char *fname;
1204   estream_t fp;
1205   char hexgrip[40+4+1];
1206
1207   bin2hex (grip, 20, hexgrip);
1208   strcpy (hexgrip+40, ".key");
1209
1210   fname = make_filename (opt_homedir, GNUPG_PRIVATE_KEYS_DIR, hexgrip, NULL);
1211   if (force)
1212     fp = es_fopen (fname, "wb");
1213   else
1214     {
1215       if (!access (fname, F_OK))
1216       {
1217         if (opt_status_msg)
1218           log_info ("[PROTECT-TOOL:] secretkey-exists\n");
1219         if (opt_no_fail_on_exist)
1220           log_info ("secret key file `%s' already exists\n", fname);
1221         else
1222           log_error ("secret key file `%s' already exists\n", fname);
1223         xfree (fname);
1224         return opt_no_fail_on_exist? 0 : -1;
1225       }
1226       /* FWIW: Under Windows Vista the standard fopen in the msvcrt
1227          fails if the "x" GNU extension is used.  */
1228       fp = es_fopen (fname, "wbx");
1229     }
1230
1231   if (!fp)
1232     {
1233       log_error ("can't create `%s': %s\n", fname, strerror (errno));
1234       xfree (fname);
1235       return -1;
1236     }
1237
1238   if (es_fwrite (buffer, length, 1, fp) != 1)
1239     {
1240       log_error ("error writing `%s': %s\n", fname, strerror (errno));
1241       es_fclose (fp);
1242       remove (fname);
1243       xfree (fname);
1244       return -1;
1245     }
1246   if (es_fclose (fp))
1247     {
1248       log_error ("error closing `%s': %s\n", fname, strerror (errno));
1249       remove (fname);
1250       xfree (fname);
1251       return -1;
1252     }
1253   log_info ("secret key stored as `%s'\n", fname);
1254
1255   if (opt_status_msg)
1256     log_info ("[PROTECT-TOOL:] secretkey-stored\n");
1257
1258   xfree (fname);
1259   return 0;
1260 }