g10/keyid.c

   1 /* keyid.c - key ID and fingerprint handling
   2  * Copyright (C) 1998, 1999, 2000, 2001, 2003,
   3  *               2004, 2006 Free Software Foundation, Inc.
   4  *
   5  * This file is part of GnuPG.
   6  *
   7  * GnuPG is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 3 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * GnuPG is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  19  */
  20
  21 #include <config.h>
  22 #include <stdio.h>
  23 #include <stdlib.h>
  24 #include <string.h>
  25 #include <errno.h>
  26 #include <time.h>
  27 #include <assert.h>
  28
  29 #include "gpg.h"
  30 #include "util.h"
  31 #include "main.h"
  32 #include "packet.h"
  33 #include "options.h"
  34 #include "keydb.h"
  35 #include "i18n.h"
  36
  37 int
  38 pubkey_letter( int algo )
  39 {
  40     switch( algo ) {
  41       case PUBKEY_ALGO_RSA:     return 'R' ;
  42       case PUBKEY_ALGO_RSA_E:   return 'r' ;
  43       case PUBKEY_ALGO_RSA_S:   return 's' ;
  44       case PUBKEY_ALGO_ELGAMAL_E: return 'g';
  45       case PUBKEY_ALGO_ELGAMAL: return 'G' ;
  46       case PUBKEY_ALGO_DSA:     return 'D' ;
  47       default: return '?';
  48     }
  49 }
  50
  51 /* This function is useful for v4 fingerprints and v3 or v4 key
  52    signing. */
  53 void
  54 hash_public_key( gcry_md_hd_t md, PKT_public_key *pk )
  55 {
  56   unsigned int n = 6;
  57   unsigned int nn[PUBKEY_MAX_NPKEY];
  58   byte *pp[PUBKEY_MAX_NPKEY];
  59   int i;
  60   unsigned int nbits;
  61   size_t nbytes;
  62   int npkey = pubkey_get_npkey (pk->pubkey_algo);
  63
  64   /* Two extra bytes for the expiration date in v3 */
  65   if(pk->version<4)
  66     n+=2;
  67
  68   if (npkey==0 && pk->pkey[0]
  69       && gcry_mpi_get_flag (pk->pkey[0], GCRYMPI_FLAG_OPAQUE))
  70     {
  71       pp[0] = gcry_mpi_get_opaque (pk->pkey[0], &nbits);
  72       nn[0] = (nbits+7)/8;
  73       n+=nn[0];
  74     }
  75   else
  76     for(i=0; i < npkey; i++ )
  77       {
  78         if (gcry_mpi_print (GCRYMPI_FMT_PGP, NULL, 0, &nbytes, pk->pkey[i]))
  79           BUG ();
  80         pp[i] = xmalloc (nbytes);
  81         if (gcry_mpi_print (GCRYMPI_FMT_PGP, pp[i], nbytes,
  82                             &nbytes, pk->pkey[i]))
  83           BUG ();
  84         nn[i] = nbytes;
  85         n += nn[i];
  86       }
  87
  88   gcry_md_putc ( md, 0x99 );     /* ctb */
  89   /* What does it mean if n is greater than than 0xFFFF ? */
  90   gcry_md_putc ( md, n >> 8 );   /* 2 byte length header */
  91   gcry_md_putc ( md, n );
  92   gcry_md_putc ( md, pk->version );
  93
  94   gcry_md_putc ( md, pk->timestamp >> 24 );
  95   gcry_md_putc ( md, pk->timestamp >> 16 );
  96   gcry_md_putc ( md, pk->timestamp >>  8 );
  97   gcry_md_putc ( md, pk->timestamp       );
  98
  99   if(pk->version<4)
 100     {
 101       u16 days=0;
 102       if(pk->expiredate)
 103         days=(u16)((pk->expiredate - pk->timestamp) / 86400L);
 104
 105       gcry_md_putc ( md, days >> 8 );
 106       gcry_md_putc ( md, days );
 107     }
 108
 109   gcry_md_putc ( md, pk->pubkey_algo );
 110
 111   if(npkey==0 && pk->pkey[0]
 112      && gcry_mpi_get_flag (pk->pkey[0], GCRYMPI_FLAG_OPAQUE))
 113     {
 114       gcry_md_write (md, pp[0], nn[0]);
 115     }
 116   else
 117     for(i=0; i < npkey; i++ )
 118       {
 119         gcry_md_write ( md, pp[i], nn[i] );
 120         xfree(pp[i]);
 121       }
 122 }
 123
 124 static gcry_md_hd_t
 125 do_fingerprint_md( PKT_public_key *pk )
 126 {
 127   gcry_md_hd_t md;
 128
 129   if (gcry_md_open (&md, DIGEST_ALGO_SHA1, 0))
 130     BUG ();
 131   hash_public_key(md,pk);
 132   gcry_md_final( md );
 133
 134   return md;
 135 }
 136
 137 static gcry_md_hd_t
 138 do_fingerprint_md_sk( PKT_secret_key *sk )
 139 {
 140     PKT_public_key pk;
 141     int npkey = pubkey_get_npkey( sk->pubkey_algo ); /* npkey is correct! */
 142     int i;
 143
 144     if(npkey==0)
 145       return NULL;
 146
 147     pk.pubkey_algo = sk->pubkey_algo;
 148     pk.version     = sk->version;
 149     pk.timestamp = sk->timestamp;
 150     pk.expiredate = sk->expiredate;
 151     pk.pubkey_algo = sk->pubkey_algo;
 152     for( i=0; i < npkey; i++ )
 153       pk.pkey[i] = sk->skey[i];
 154     return do_fingerprint_md( &pk );
 155 }
 156
 157
 158 u32
 159 v3_keyid (gcry_mpi_t a, u32 *ki)
 160 {
 161   byte *buffer, *p;
 162   size_t nbytes;
 163
 164   if (gcry_mpi_print (GCRYMPI_FMT_USG, NULL, 0, &nbytes, a ))
 165     BUG ();
 166   /* fixme: allocate it on the stack */
 167   buffer = xmalloc (nbytes);
 168   if (gcry_mpi_print( GCRYMPI_FMT_USG, buffer, nbytes, NULL, a ))
 169     BUG ();
 170   if (nbytes < 8) /* oops */
 171     ki[0] = ki[1] = 0;
 172   else
 173     {
 174       p = buffer + nbytes - 8;
 175       ki[0] = (p[0] << 24) | (p[1] <<16) | (p[2] << 8) | p[3];
 176       p += 4;
 177       ki[1] = (p[0] << 24) | (p[1] <<16) | (p[2] << 8) | p[3];
 178     }
 179   xfree (buffer);
 180   return ki[1];
 181 }
 182
 183
 184 size_t
 185 keystrlen(void)
 186 {
 187   switch(opt.keyid_format)
 188     {
 189     case KF_SHORT:
 190       return 8;
 191
 192     case KF_LONG:
 193       return 16;
 194
 195     case KF_0xSHORT:
 196       return 10;
 197
 198     case KF_0xLONG:
 199       return 18;
 200
 201     default:
 202       BUG();
 203     }
 204 }
 205
 206 const char *
 207 keystr(u32 *keyid)
 208 {
 209   static char keyid_str[19];
 210
 211   switch(opt.keyid_format)
 212     {
 213     case KF_SHORT:
 214       sprintf(keyid_str,"%08lX",(ulong)keyid[1]);
 215       break;
 216
 217     case KF_LONG:
 218       if(keyid[0])
 219         sprintf(keyid_str,"%08lX%08lX",(ulong)keyid[0],(ulong)keyid[1]);
 220       else
 221         sprintf(keyid_str,"%08lX",(ulong)keyid[1]);
 222       break;
 223
 224     case KF_0xSHORT:
 225       sprintf(keyid_str,"0x%08lX",(ulong)keyid[1]);
 226       break;
 227
 228     case KF_0xLONG:
 229       if(keyid[0])
 230         sprintf(keyid_str,"0x%08lX%08lX",(ulong)keyid[0],(ulong)keyid[1]);
 231       else
 232         sprintf(keyid_str,"0x%08lX",(ulong)keyid[1]);
 233       break;
 234
 235     default:
 236       BUG();
 237     }
 238
 239   return keyid_str;
 240 }
 241
 242 const char *
 243 keystr_from_pk(PKT_public_key *pk)
 244 {
 245   keyid_from_pk(pk,NULL);
 246
 247   return keystr(pk->keyid);
 248 }
 249
 250 const char *
 251 keystr_from_sk(PKT_secret_key *sk)
 252 {
 253   keyid_from_sk(sk,NULL);
 254
 255   return keystr(sk->keyid);
 256 }
 257
 258 const char *
 259 keystr_from_desc(KEYDB_SEARCH_DESC *desc)
 260 {
 261   switch(desc->mode)
 262     {
 263     case KEYDB_SEARCH_MODE_LONG_KID:
 264     case KEYDB_SEARCH_MODE_SHORT_KID:
 265       return keystr(desc->u.kid);
 266
 267     case KEYDB_SEARCH_MODE_FPR20:
 268       {
 269         u32 keyid[2];
 270
 271         keyid[0] = ((unsigned char)desc->u.fpr[12] << 24
 272                     | (unsigned char)desc->u.fpr[13] << 16
 273                     | (unsigned char)desc->u.fpr[14] << 8
 274                     | (unsigned char)desc->u.fpr[15]);
 275         keyid[1] = ((unsigned char)desc->u.fpr[16] << 24
 276                     | (unsigned char)desc->u.fpr[17] << 16
 277                     | (unsigned char)desc->u.fpr[18] << 8
 278                     | (unsigned char)desc->u.fpr[19]);
 279
 280         return keystr(keyid);
 281       }
 282
 283     case KEYDB_SEARCH_MODE_FPR16:
 284       return "?v3 fpr?";
 285
 286     default:
 287       BUG();
 288     }
 289 }
 290
 291 /****************
 292  * Get the keyid from the secret key and put it into keyid
 293  * if this is not NULL. Return the 32 low bits of the keyid.
 294  */
 295 u32
 296 keyid_from_sk( PKT_secret_key *sk, u32 *keyid )
 297 {
 298   u32 lowbits;
 299   u32 dummy_keyid[2];
 300
 301   if( !keyid )
 302     keyid = dummy_keyid;
 303
 304   if( sk->keyid[0] || sk->keyid[1] )
 305     {
 306       keyid[0] = sk->keyid[0];
 307       keyid[1] = sk->keyid[1];
 308       lowbits = keyid[1];
 309     }
 310   else if( sk->version < 4 )
 311     {
 312       if( is_RSA(sk->pubkey_algo) )
 313         {
 314           lowbits = (pubkey_get_npkey (sk->pubkey_algo) ?
 315                      v3_keyid( sk->skey[0], keyid ) : 0); /* Take n. */
 316           sk->keyid[0]=keyid[0];
 317           sk->keyid[1]=keyid[1];
 318         }
 319       else
 320         sk->keyid[0]=sk->keyid[1]=keyid[0]=keyid[1]=lowbits=0xFFFFFFFF;
 321     }
 322   else
 323     {
 324       const byte *dp;
 325       gcry_md_hd_t md;
 326
 327       md = do_fingerprint_md_sk(sk);
 328       if(md)
 329         {
 330           dp = gcry_md_read (md, 0);
 331           keyid[0] = dp[12] << 24 | dp[13] << 16 | dp[14] << 8 | dp[15] ;
 332           keyid[1] = dp[16] << 24 | dp[17] << 16 | dp[18] << 8 | dp[19] ;
 333           lowbits = keyid[1];
 334           gcry_md_close (md);
 335           sk->keyid[0] = keyid[0];
 336           sk->keyid[1] = keyid[1];
 337         }
 338       else
 339         sk->keyid[0]=sk->keyid[1]=keyid[0]=keyid[1]=lowbits=0xFFFFFFFF;
 340     }
 341
 342   return lowbits;
 343 }
 344
 345
 346 /****************
 347  * Get the keyid from the public key and put it into keyid
 348  * if this is not NULL. Return the 32 low bits of the keyid.
 349  */
 350 u32
 351 keyid_from_pk( PKT_public_key *pk, u32 *keyid )
 352 {
 353   u32 lowbits;
 354   u32 dummy_keyid[2];
 355
 356   if( !keyid )
 357     keyid = dummy_keyid;
 358
 359   if( pk->keyid[0] || pk->keyid[1] )
 360     {
 361       keyid[0] = pk->keyid[0];
 362       keyid[1] = pk->keyid[1];
 363       lowbits = keyid[1];
 364     }
 365   else if( pk->version < 4 )
 366     {
 367       if( is_RSA(pk->pubkey_algo) )
 368         {
 369           lowbits = (pubkey_get_npkey (pk->pubkey_algo) ?
 370                      v3_keyid ( pk->pkey[0], keyid ) : 0); /* From n. */
 371           pk->keyid[0] = keyid[0];
 372           pk->keyid[1] = keyid[1];
 373         }
 374       else
 375         pk->keyid[0]=pk->keyid[1]=keyid[0]=keyid[1]=lowbits=0xFFFFFFFF;
 376     }
 377   else
 378     {
 379       const byte *dp;
 380       gcry_md_hd_t md;
 381
 382       md = do_fingerprint_md(pk);
 383       if(md)
 384         {
 385           dp = gcry_md_read ( md, 0 );
 386           keyid[0] = dp[12] << 24 | dp[13] << 16 | dp[14] << 8 | dp[15] ;
 387           keyid[1] = dp[16] << 24 | dp[17] << 16 | dp[18] << 8 | dp[19] ;
 388           lowbits = keyid[1];
 389           gcry_md_close (md);
 390           pk->keyid[0] = keyid[0];
 391           pk->keyid[1] = keyid[1];
 392         }
 393       else
 394         pk->keyid[0]=pk->keyid[1]=keyid[0]=keyid[1]=lowbits=0xFFFFFFFF;
 395     }
 396
 397   return lowbits;
 398 }
 399
 400
 401 /****************
 402  * Get the keyid from the fingerprint.  This function is simple for most
 403  * keys, but has to do a keylookup for old stayle keys.
 404  */
 405 u32
 406 keyid_from_fingerprint( const byte *fprint, size_t fprint_len, u32 *keyid )
 407 {
 408     u32 dummy_keyid[2];
 409
 410     if( !keyid )
 411         keyid = dummy_keyid;
 412
 413     if( fprint_len != 20 ) {
 414         /* This is special as we have to lookup the key first */
 415         PKT_public_key pk;
 416         int rc;
 417
 418         memset( &pk, 0, sizeof pk );
 419         rc = get_pubkey_byfprint( &pk, fprint, fprint_len );
 420         if( rc ) {
 421             log_error("Oops: keyid_from_fingerprint: no pubkey\n");
 422             keyid[0] = 0;
 423             keyid[1] = 0;
 424         }
 425         else
 426             keyid_from_pk( &pk, keyid );
 427     }
 428     else {
 429         const byte *dp = fprint;
 430         keyid[0] = dp[12] << 24 | dp[13] << 16 | dp[14] << 8 | dp[15] ;
 431         keyid[1] = dp[16] << 24 | dp[17] << 16 | dp[18] << 8 | dp[19] ;
 432     }
 433
 434     return keyid[1];
 435 }
 436
 437
 438 u32
 439 keyid_from_sig( PKT_signature *sig, u32 *keyid )
 440 {
 441     if( keyid ) {
 442         keyid[0] = sig->keyid[0];
 443         keyid[1] = sig->keyid[1];
 444     }
 445     return sig->keyid[1];
 446 }
 447
 448 byte *
 449 namehash_from_uid(PKT_user_id *uid)
 450 {
 451   if(uid->namehash==NULL)
 452     {
 453       uid->namehash = xmalloc(20);
 454
 455       if(uid->attrib_data)
 456         gcry_md_hash_buffer (GCRY_MD_RMD160, uid->namehash,
 457                              uid->attrib_data, uid->attrib_len);
 458       else
 459         gcry_md_hash_buffer (GCRY_MD_RMD160, uid->namehash,
 460                              uid->name, uid->len);
 461     }
 462
 463   return uid->namehash;
 464 }
 465
 466 /****************
 467  * return the number of bits used in the pk
 468  */
 469 unsigned
 470 nbits_from_pk( PKT_public_key *pk )
 471 {
 472     return pubkey_nbits( pk->pubkey_algo, pk->pkey );
 473 }
 474
 475 /****************
 476  * return the number of bits used in the sk
 477  */
 478 unsigned
 479 nbits_from_sk( PKT_secret_key *sk )
 480 {
 481     return pubkey_nbits( sk->pubkey_algo, sk->skey );
 482 }
 483
 484 static const char *
 485 mk_datestr (char *buffer, time_t atime)
 486 {
 487     struct tm *tp;
 488
 489     if ( atime < 0 ) /* 32 bit time_t and after 2038-01-19 */
 490         strcpy (buffer, "????" "-??" "-??"); /* mark this as invalid */
 491     else {
 492         tp = gmtime (&atime);
 493         sprintf (buffer,"%04d-%02d-%02d",
 494                  1900+tp->tm_year, tp->tm_mon+1, tp->tm_mday );
 495     }
 496     return buffer;
 497 }
 498
 499 /****************
 500  * return a string with the creation date of the pk
 501  * Note: this is alloced in a static buffer.
 502  *    Format is: yyyy-mm-dd
 503  */
 504 const char *
 505 datestr_from_pk( PKT_public_key *pk )
 506 {
 507     static char buffer[11+5];
 508     time_t atime = pk->timestamp;
 509
 510     return mk_datestr (buffer, atime);
 511 }
 512
 513 const char *
 514 datestr_from_sk( PKT_secret_key *sk )
 515 {
 516     static char buffer[11+5];
 517     time_t atime = sk->timestamp;
 518
 519     return mk_datestr (buffer, atime);
 520 }
 521
 522 const char *
 523 datestr_from_sig( PKT_signature *sig )
 524 {
 525     static char buffer[11+5];
 526     time_t atime = sig->timestamp;
 527
 528     return mk_datestr (buffer, atime);
 529 }
 530
 531 const char *
 532 expirestr_from_pk( PKT_public_key *pk )
 533 {
 534     static char buffer[11+5];
 535     time_t atime;
 536
 537     if( !pk->expiredate )
 538         return _("never     ");
 539     atime = pk->expiredate;
 540     return mk_datestr (buffer, atime);
 541 }
 542
 543 const char *
 544 expirestr_from_sk( PKT_secret_key *sk )
 545 {
 546     static char buffer[11+5];
 547     time_t atime;
 548
 549     if( !sk->expiredate )
 550         return _("never     ");
 551     atime = sk->expiredate;
 552     return mk_datestr (buffer, atime);
 553 }
 554
 555 const char *
 556 expirestr_from_sig( PKT_signature *sig )
 557 {
 558     static char buffer[11+5];
 559     time_t atime;
 560
 561     if(!sig->expiredate)
 562       return _("never     ");
 563     atime=sig->expiredate;
 564     return mk_datestr (buffer, atime);
 565 }
 566
 567 const char *
 568 revokestr_from_pk( PKT_public_key *pk )
 569 {
 570     static char buffer[11+5];
 571     time_t atime;
 572
 573     if(!pk->revoked.date)
 574       return _("never     ");
 575     atime=pk->revoked.date;
 576     return mk_datestr (buffer, atime);
 577 }
 578
 579
 580 const char *
 581 usagestr_from_pk( PKT_public_key *pk )
 582 {
 583   static char buffer[10];
 584   int i = 0;
 585   unsigned int use = pk->pubkey_usage;
 586
 587   if ( use & PUBKEY_USAGE_SIG )
 588     buffer[i++] = 'S';
 589
 590   if ( use & PUBKEY_USAGE_CERT )
 591     buffer[i++] = 'C';
 592
 593   if ( use & PUBKEY_USAGE_ENC )
 594     buffer[i++] = 'E';
 595
 596   if ( (use & PUBKEY_USAGE_AUTH) )
 597     buffer[i++] = 'A';
 598
 599   while (i < 4)
 600     buffer[i++] = ' ';
 601
 602   buffer[i] = 0;
 603   return buffer;
 604 }
 605
 606
 607 const char *
 608 colon_strtime (u32 t)
 609 {
 610     if (!t)
 611         return "";
 612     if (opt.fixed_list_mode) {
 613         static char buf[15];
 614         sprintf (buf, "%lu", (ulong)t);
 615         return buf;
 616     }
 617     return strtimestamp(t);
 618 }
 619
 620 const char *
 621 colon_datestr_from_pk (PKT_public_key *pk)
 622 {
 623     if (opt.fixed_list_mode) {
 624         static char buf[15];
 625         sprintf (buf, "%lu", (ulong)pk->timestamp);
 626         return buf;
 627     }
 628     return datestr_from_pk (pk);
 629 }
 630
 631 const char *
 632 colon_datestr_from_sk (PKT_secret_key *sk)
 633 {
 634     if (opt.fixed_list_mode) {
 635         static char buf[15];
 636         sprintf (buf, "%lu", (ulong)sk->timestamp);
 637         return buf;
 638     }
 639     return datestr_from_sk (sk);
 640 }
 641
 642 const char *
 643 colon_datestr_from_sig (PKT_signature *sig)
 644 {
 645     if (opt.fixed_list_mode) {
 646         static char buf[15];
 647         sprintf (buf, "%lu", (ulong)sig->timestamp);
 648         return buf;
 649     }
 650     return datestr_from_sig (sig);
 651 }
 652
 653 const char *
 654 colon_expirestr_from_sig (PKT_signature *sig)
 655 {
 656     if(!sig->expiredate)
 657         return "";
 658     if (opt.fixed_list_mode) {
 659         static char buf[15];
 660         sprintf (buf, "%lu", (ulong)sig->expiredate);
 661         return buf;
 662     }
 663     return expirestr_from_sig (sig);
 664 }
 665
 666
 667 /**************** .
 668  * Return a byte array with the fingerprint for the given PK/SK
 669  * The length of the array is returned in ret_len. Caller must free
 670  * the array or provide an array of length MAX_FINGERPRINT_LEN.
 671  */
 672
 673 byte *
 674 fingerprint_from_pk( PKT_public_key *pk, byte *array, size_t *ret_len )
 675 {
 676   byte *buf;
 677   const byte *dp;
 678   size_t len, nbytes;
 679   int i;
 680
 681   if ( pk->version < 4 )
 682     {
 683       if ( is_RSA(pk->pubkey_algo) )
 684         {
 685           /* RSA in version 3 packets is special. */
 686           gcry_md_hd_t md;
 687
 688           if (gcry_md_open (&md, DIGEST_ALGO_MD5, 0))
 689             BUG ();
 690           if ( pubkey_get_npkey (pk->pubkey_algo) > 1 )
 691             {
 692               for (i=0; i < 2; i++)
 693                 {
 694                   if (gcry_mpi_print (GCRYMPI_FMT_USG, NULL, 0,
 695                                       &nbytes, pk->pkey[i]))
 696                     BUG ();
 697                   /* fixme: Better allocate BUF on the stack */
 698                   buf = xmalloc (nbytes);
 699                   if (gcry_mpi_print (GCRYMPI_FMT_USG, buf, nbytes,
 700                                       NULL, pk->pkey[i]))
 701                     BUG ();
 702                   gcry_md_write (md, buf, nbytes);
 703                   xfree (buf);
 704                 }
 705             }
 706           gcry_md_final (md);
 707           if (!array)
 708             array = xmalloc (16);
 709           len = 16;
 710           memcpy (array, gcry_md_read (md, DIGEST_ALGO_MD5), 16);
 711           gcry_md_close(md);
 712         }
 713       else
 714         {
 715           if (!array)
 716             array = xmalloc(16);
 717           len = 16;
 718           memset (array,0,16);
 719         }
 720     }
 721   else
 722     {
 723       gcry_md_hd_t md;
 724
 725       md = do_fingerprint_md(pk);
 726       dp = gcry_md_read( md, 0 );
 727       len = gcry_md_get_algo_dlen (gcry_md_get_algo (md));
 728       assert( len <= MAX_FINGERPRINT_LEN );
 729       if (!array)
 730         array = xmalloc ( len );
 731       memcpy (array, dp, len );
 732       pk->keyid[0] = dp[12] << 24 | dp[13] << 16 | dp[14] << 8 | dp[15] ;
 733       pk->keyid[1] = dp[16] << 24 | dp[17] << 16 | dp[18] << 8 | dp[19] ;
 734       gcry_md_close( md);
 735     }
 736
 737   *ret_len = len;
 738   return array;
 739 }
 740
 741 byte *
 742 fingerprint_from_sk( PKT_secret_key *sk, byte *array, size_t *ret_len )
 743 {
 744   byte *buf;
 745   const char *dp;
 746   size_t len, nbytes;
 747   int i;
 748
 749   if (sk->version < 4)
 750     {
 751       if ( is_RSA(sk->pubkey_algo) )
 752         {
 753           /* RSA in version 3 packets is special. */
 754           gcry_md_hd_t md;
 755
 756           if (gcry_md_open (&md, DIGEST_ALGO_MD5, 0))
 757             BUG ();
 758           if (pubkey_get_npkey( sk->pubkey_algo ) > 1)
 759             {
 760               for (i=0; i < 2; i++)
 761                 {
 762                   if (gcry_mpi_print (GCRYMPI_FMT_USG, NULL, 0,
 763                                       &nbytes, sk->skey[i]))
 764                     BUG ();
 765                   /* fixme: Better allocate BUF on the stack */
 766                   buf = xmalloc (nbytes);
 767                   if (gcry_mpi_print (GCRYMPI_FMT_USG, buf, nbytes,
 768                                       NULL, sk->skey[i]))
 769                     BUG ();
 770                   gcry_md_write (md, buf, nbytes);
 771                   xfree (buf);
 772                 }
 773             }
 774           gcry_md_final(md);
 775           if (!array)
 776             array = xmalloc (16);
 777           len = 16;
 778           memcpy (array, gcry_md_read (md, DIGEST_ALGO_MD5), 16);
 779           gcry_md_close (md);
 780         }
 781       else
 782         {
 783           if (!array)
 784             array = xmalloc (16);
 785           len=16;
 786           memset (array,0,16);
 787         }
 788     }
 789   else
 790     {
 791       gcry_md_hd_t md;
 792
 793       md = do_fingerprint_md_sk(sk);
 794       if (md)
 795         {
 796           dp = gcry_md_read ( md, 0 );
 797           len = gcry_md_get_algo_dlen ( gcry_md_get_algo (md) );
 798           assert ( len <= MAX_FINGERPRINT_LEN );
 799           if (!array)
 800             array = xmalloc( len );
 801           memcpy (array, dp, len);
 802           gcry_md_close (md);
 803         }
 804       else
 805         {
 806           len = MAX_FINGERPRINT_LEN;
 807           if (!array)
 808             array = xmalloc (len);
 809           memset (array, 0, len);
 810         }
 811     }
 812
 813   *ret_len = len;
 814   return array;
 815 }
 816
 817
 818 /* Create a serialno/fpr string from the serial number and the secret
 819    key.  Caller must free the returned string.  There is no error
 820    return.  */
 821 char *
 822 serialno_and_fpr_from_sk (const unsigned char *sn, size_t snlen,
 823                           PKT_secret_key *sk)
 824 {
 825   unsigned char fpr[MAX_FINGERPRINT_LEN];
 826   size_t fprlen;
 827   char *buffer, *p;
 828   int i;
 829
 830   fingerprint_from_sk (sk, fpr, &fprlen);
 831   buffer = p = xmalloc (snlen*2 + 1 + fprlen*2 + 1);
 832   for (i=0; i < snlen; i++, p+=2)
 833     sprintf (p, "%02X", sn[i]);
 834   *p++ = '/';
 835   for (i=0; i < fprlen; i++, p+=2)
 836     sprintf (p, "%02X", fpr[i]);
 837   *p = 0;
 838   return buffer;
 839 }
 840