(show_key_with_all_names): Print the card S/N.
[gnupg.git] / g10 / seckey-cert.c
index 6bffb78..7356cb2 100644 (file)
@@ -1,14 +1,15 @@
-/* seckey-cert.c -  secret key certifucate packet handling
- *     Copyright (C) 1998 Free Software Foundation, Inc.
+/* seckey-cert.c -  secret key certificate packet handling
+ * Copyright (C) 1998, 1999, 2000, 2001, 2002,
+ *               2003 Free Software Foundation, Inc.
  *
- * This file is part of GNUPG.
+ * This file is part of GnuPG.
  *
- * GNUPG is free software; you can redistribute it and/or modify
+ * GnuPG is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation; either version 2 of the License, or
  * (at your option) any later version.
  *
- * GNUPG is distributed in the hope that it will be useful,
+ * GnuPG is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
@@ -23,6 +24,8 @@
 #include <stdlib.h>
 #include <string.h>
 #include <assert.h>
+
+#include "gpg.h"
 #include "util.h"
 #include "memory.h"
 #include "packet.h"
 #include "main.h"
 #include "options.h"
 #include "i18n.h"
-
+#include "status.h"
+#include "pkglue.h"
 
 static int
-do_check( PKT_secret_key *sk )
+do_check( PKT_secret_key *sk, const char *tryagain_text, int mode,
+          int *canceled )
 {
     byte *buffer;
     u16 csum=0;
     int i, res;
     unsigned nbytes;
+    gpg_error_t rc;
 
     if( sk->is_protected ) { /* remove the protection */
        DEK *dek = NULL;
-       u32 keyid[2];
+       u32 keyid[4]; /* 4! because we need two of them */
        CIPHER_HANDLE cipher_hd=NULL;
        PKT_secret_key *save_sk;
-       char save_iv[8];
 
+       if( sk->protect.s2k.mode == 1001 ) {
+           log_info(_("secret key parts are not available\n"));
+           return GPG_ERR_GENERAL;
+       }
        if( sk->protect.algo == CIPHER_ALGO_NONE )
            BUG();
-       if( check_cipher_algo( sk->protect.algo ) )
-           return G10ERR_CIPHER_ALGO; /* unsupported protection algorithm */
-       if( cipher_get_blocksize( sk->protect.algo ) != 8 )
-           return G10ERR_CIPHER_ALGO; /* unsupported protection algorithm */
+       if( openpgp_cipher_test_algo( sk->protect.algo ) ) {
+           log_info(_("protection algorithm %d%s is not supported\n"),
+                       sk->protect.algo,sk->protect.algo==1?" (IDEA)":"" );
+           if (sk->protect.algo==CIPHER_ALGO_IDEA)
+              {
+                write_status (STATUS_RSA_OR_IDEA);
+                idea_cipher_warn (0);
+              }
+           return GPG_ERR_CIPHER_ALGO;
+       }
        keyid_from_sk( sk, keyid );
-       dek = passphrase_to_dek( keyid, sk->protect.algo,
-                                &sk->protect.s2k, 0 );
-       cipher_hd = cipher_open( sk->protect.algo,
-                                CIPHER_MODE_AUTO_CFB, 1);
-       cipher_setkey( cipher_hd, dek->key, dek->keylen );
-       cipher_setiv( cipher_hd, NULL );
-       m_free(dek);
+       keyid[2] = keyid[3] = 0;
+       if( !sk->is_primary ) {
+            keyid[2] = sk->main_keyid[0];
+            keyid[3] = sk->main_keyid[1];
+       }
+       dek = passphrase_to_dek( keyid, sk->pubkey_algo, sk->protect.algo,
+                                &sk->protect.s2k, mode,
+                                 tryagain_text, canceled );
+        if (!dek && canceled && *canceled)
+           return GPG_ERR_GENERAL;
+
+       rc = gcry_cipher_open (&cipher_hd, sk->protect.algo,
+                               GCRY_CIPHER_MODE_CFB,
+                               GCRY_CIPHER_SECURE
+                               | (sk->protect.algo >= 100 ?
+                                  0 : GCRY_CIPHER_ENABLE_SYNC));
+        if (rc)
+          log_fatal ("cipher open failed: %s\n", gpg_strerror (rc) );
+
+       rc = gcry_cipher_setkey (cipher_hd, dek->key, dek->keylen);
+        if (rc)
+          log_fatal ("set key failed: %s\n", gpg_strerror (rc) );
+
+       xfree (dek);
        save_sk = copy_secret_key( NULL, sk );
-       memcpy(save_iv, sk->protect.iv, 8 );
-       cipher_decrypt( cipher_hd, sk->protect.iv, sk->protect.iv, 8 );
+       gcry_cipher_setiv (cipher_hd, sk->protect.iv, sk->protect.ivlen);
        csum = 0;
-       for(i=pubkey_get_npkey(sk->pubkey_algo);
-               i < pubkey_get_nskey(sk->pubkey_algo); i++ ) {
-           buffer = mpi_get_secure_buffer( sk->skey[i], &nbytes, NULL );
-           cipher_sync( cipher_hd );
-           assert( mpi_is_protected(sk->skey[i]) );
-           cipher_decrypt( cipher_hd, buffer, buffer, nbytes );
-           mpi_set_buffer( sk->skey[i], buffer, nbytes, 0 );
-           mpi_clear_protect_flag( sk->skey[i] );
-           csum += checksum_mpi( sk->skey[i] );
-           m_free( buffer );
+       if( sk->version >= 4 ) {
+           int ndata;
+            unsigned int ndatabits;
+           byte *p, *data;
+            u16 csumc = 0;
+
+           i = pubkey_get_npkey(sk->pubkey_algo);
+            assert( gcry_mpi_get_flag (sk->skey[i], GCRYMPI_FLAG_OPAQUE ));
+            p = gcry_mpi_get_opaque( sk->skey[i], &ndatabits );
+            ndata = (ndatabits+7)/8;
+            if ( ndata > 1 )
+                csumc = p[ndata-2] << 8 | p[ndata-1];
+           data = gcry_xmalloc_secure ( ndata );
+           gcry_cipher_decrypt( cipher_hd, data, ndata, p, ndata );
+           gcry_mpi_release ( sk->skey[i] ); sk->skey[i] = NULL ;
+           p = data;
+            if (sk->protect.sha1chk) {
+                /* This is the new SHA1 checksum method to detect
+                   tampering with the key as used by the Klima/Rosa
+                   attack */
+                sk->csum = 0;
+                csum = 1;
+                if( ndata < 20 ) 
+                    log_error("not enough bytes for SHA-1 checksum\n");
+                else {
+                    gcry_md_hd_t h;
+
+                    if ( gcry_md_open (&h, DIGEST_ALGO_SHA1, 1))
+                        BUG(); /* algo not available */
+                    gcry_md_write (h, data, ndata - 20);
+                    gcry_md_final (h);
+                    if (!memcmp (gcry_md_read (h, DIGEST_ALGO_SHA1),
+                                 data + ndata - 20, 20) ) {
+                        /* digest does match.  We have to keep the old
+                           style checksum in sk->csum, so that the
+                           test used for unprotected keys does work.
+                           This test gets used when we are adding new
+                           keys. */
+                        sk->csum = csum = checksum (data, ndata-20);
+                    }
+                    gcry_md_close (h);
+                }
+            }
+            else {
+                if( ndata < 2 ) {
+                    log_error("not enough bytes for checksum\n");
+                    sk->csum = 0;
+                    csum = 1;
+                }
+                else {
+                    csum = checksum( data, ndata-2);
+                    sk->csum = data[ndata-2] << 8 | data[ndata-1];
+                    if ( sk->csum != csum ) {
+                        /* This is a PGP 7.0.0 workaround */
+                        sk->csum = csumc; /* take the encrypted one */
+                    }
+                }
+            }
+                
+            /* must check it here otherwise the mpi_read_xx would fail
+               because the length may have an arbitrary value */
+            if( sk->csum == csum ) {
+                for( ; i < pubkey_get_nskey(sk->pubkey_algo); i++ ) {
+                   assert( gcry_is_secure( p ) );
+                   res = gcry_mpi_scan( &sk->skey[i], GCRYMPI_FMT_PGP,
+                                         p, ndata, &nbytes);
+                   if( res )
+                       log_bug ("gcry_mpi_scan failed in do_check: %s\n",
+                                 gpg_strerror (res));
+                    ndata -= nbytes;
+                    p += nbytes;
+                }
+                /* Note: at this point ndata should be 2 for a simple
+                   checksum or 20 for the sha1 digest */
+            }
+           xfree (data);
        }
-       if( opt.emulate_bugs & EMUBUG_GPGCHKSUM ) {
-          csum = sk->csum;
+       else {
+           for(i=pubkey_get_npkey(sk->pubkey_algo);
+                   i < pubkey_get_nskey(sk->pubkey_algo); i++ ) {
+                byte *p;
+                int ndata;
+                unsigned int ndatabits;
+
+                assert( gcry_mpi_get_flag (sk->skey[i], GCRYMPI_FLAG_OPAQUE));
+                p = gcry_mpi_get_opaque( sk->skey[i], &ndatabits );
+                ndata = (ndatabits+7)/8;
+                assert (ndata >= 2);
+                assert (ndata == ((p[0] << 8 | p[1]) + 7)/8 + 2);
+                buffer = gcry_xmalloc_secure (ndata);
+               gcry_cipher_sync (cipher_hd);
+                buffer[0] = p[0];
+                buffer[1] = p[1];
+                gcry_cipher_decrypt (cipher_hd, buffer+2, ndata-2,
+                                     p+2, ndata-2);
+                csum += checksum (buffer, ndata);
+                gcry_mpi_release (sk->skey[i]);
+               res = gcry_mpi_scan( &sk->skey[i], GCRYMPI_FMT_USG,
+                                    buffer, ndata, &ndata );
+               if( res )
+                   log_bug ("gcry_mpi_scan failed in do_check: %s\n", 
+                             gpg_strerror (res));
+
+                assert (sk->skey[i]);
+               xfree (buffer);
+/*             csum += checksum_mpi (sk->skey[i]); */
+           }
        }
-       cipher_close( cipher_hd );
+       gcry_cipher_close (cipher_hd);
        /* now let's see whether we have used the right passphrase */
        if( csum != sk->csum ) {
            copy_secret_key( sk, save_sk );
+            passphrase_clear_cache ( keyid, sk->pubkey_algo );
            free_secret_key( save_sk );
-           memcpy( sk->protect.iv, save_iv, 8 );
-           return G10ERR_BAD_PASS;
+           return gpg_error (GPG_ERR_BAD_PASSPHRASE);
        }
        /* the checksum may fail, so we also check the key itself */
-       res = pubkey_check_secret_key( sk->pubkey_algo, sk->skey );
-       if( res ) {
-           copy_secret_key( sk, save_sk );
-           free_secret_key( save_sk );
-           memcpy( sk->protect.iv, save_iv, 8 );
-           return G10ERR_BAD_PASS;
-       }
+       res = pk_check_secret_key (sk->pubkey_algo, sk->skey);
+       if (res) {
+            copy_secret_key( sk, save_sk );
+            passphrase_clear_cache ( keyid, sk->pubkey_algo );
+            free_secret_key( save_sk );
+           return gpg_error (GPG_ERR_BAD_PASSPHRASE);
+       }
        free_secret_key( save_sk );
        sk->is_protected = 0;
     }
@@ -107,7 +232,7 @@ do_check( PKT_secret_key *sk )
            csum += checksum_mpi( sk->skey[i] );
        }
        if( csum != sk->csum )
-           return G10ERR_CHECKSUM;
+           return GPG_ERR_CHECKSUM;
     }
 
     return 0;
@@ -117,48 +242,67 @@ do_check( PKT_secret_key *sk )
 
 /****************
  * Check the secret key
- * Ask up to 3 times for a correct passphrase
+ * Ask up to 3 (or n) times for a correct passphrase
+ * If n is negative, disable the key info prompt and make n=abs(n)
  */
 int
-check_secret_key( PKT_secret_key *sk )
+check_secret_key( PKT_secret_key *sk, int n )
 {
-    int rc = G10ERR_BAD_PASS;
-    int i;
-
-    for(i=0; i < 3 && rc == G10ERR_BAD_PASS; i++ ) {
-       if( i )
-           log_error(_("Invalid passphrase; please try again ...\n"));
-       rc = do_check( sk );
-      #if 0 /* set to 1 to enable the workaround */
-       if( rc == G10ERR_BAD_PASS && sk->is_protected
-           && sk->protect.algo == CIPHER_ALGO_BLOWFISH
-           && sk->pubkey_algo != PUBKEY_ALGO_ELGAMAL ) {
-           /* Workaround for a bug in 0.2.16 which still used
-            * a 160 bit key for BLOWFISH. */
-           log_info("trying workaround for 0.2.16 passphrase bug ...\n");
-           log_info("If you don't need this, uncomment it in g10/seckey-cert.c\n\n");
-           sk->protect.algo = CIPHER_ALGO_BLOWFISH160;
-           rc = do_check( sk );
-           if( rc )
-               rc = G10ERR_BAD_PASS;
-           sk->protect.algo = CIPHER_ALGO_BLOWFISH;
+    int rc = gpg_error (GPG_ERR_BAD_PASSPHRASE);
+    int i,mode;
+
+    if (sk && sk->is_protected && sk->protect.s2k.mode == 1002)
+      return 0; /* Let the scdaemon handle it. */
+
+    if(n<0)
+      {
+       n=abs(n);
+       mode=1;
+      }
+    else
+      mode=0;
+
+    if( n < 1 )
+       n = (opt.batch && !opt.use_agent)? 1 : 3; /* use the default value */
+
+    for(i=0; i < n && gpg_err_code (rc) == GPG_ERR_BAD_PASSPHRASE; i++ ) {
+        int canceled = 0;
+        const char *tryagain = NULL;
+       if (i) {
+            tryagain = N_("Invalid passphrase; please try again");
+            log_info (_("%s ...\n"), _(tryagain));
+        }
+       rc = do_check( sk, tryagain, mode, &canceled );
+       if( gpg_err_code (rc) == GPG_ERR_BAD_PASSPHRASE
+            && is_status_enabled() ) {
+           u32 kid[2];
+           char buf[50];
+
+           keyid_from_sk( sk, kid );
+           sprintf(buf, "%08lX%08lX", (ulong)kid[0], (ulong)kid[1]);
+           write_status_text( STATUS_BAD_PASSPHRASE, buf );
        }
-      #endif
-       if( get_passphrase_fd() != -1 )
+       if( have_static_passphrase() || canceled)
            break;
     }
 
+    if( !rc )
+       write_status( STATUS_GOOD_PASSPHRASE );
+
     return rc;
 }
 
 /****************
  * check whether the secret key is protected.
  * Returns: 0 not protected, -1 on error or the protection algorithm
+ *                           -2 indicates a card stub.
  */
 int
 is_secret_key_protected( PKT_secret_key *sk )
 {
-    return sk->is_protected? sk->protect.algo : 0;
+    return sk->is_protected?
+               sk->protect.s2k.mode == 1002? -2
+                                           : sk->protect.algo : 0;
 }
 
 
@@ -169,7 +313,7 @@ is_secret_key_protected( PKT_secret_key *sk )
 int
 protect_secret_key( PKT_secret_key *sk, DEK *dek )
 {
-    int i, rc = 0;
+    int i,j, rc = 0;
     byte *buffer;
     unsigned nbytes;
     u16 csum;
@@ -178,37 +322,131 @@ protect_secret_key( PKT_secret_key *sk, DEK *dek )
        return 0;
 
     if( !sk->is_protected ) { /* okay, apply the protection */
-       CIPHER_HANDLE cipher_hd=NULL;
+       gcry_cipher_hd_t cipher_hd=NULL;
 
-       if( check_cipher_algo( sk->protect.algo ) )
-           rc = G10ERR_CIPHER_ALGO; /* unsupport protection algorithm */
-       else if( cipher_get_blocksize( sk->protect.algo ) != 8 )
-           rc = G10ERR_CIPHER_ALGO; /* unsupport protection algorithm */
+       if( openpgp_cipher_test_algo( sk->protect.algo ) )
+          {
+           rc = gpg_error (GPG_ERR_CIPHER_ALGO); /* unsupport
+                                                     protection
+                                                     algorithm */
+          }
        else {
-           cipher_hd = cipher_open( sk->protect.algo,
-                                    CIPHER_MODE_AUTO_CFB, 1 );
-           cipher_setkey( cipher_hd, dek->key, dek->keylen );
-           cipher_setiv( cipher_hd, NULL );
-           cipher_encrypt( cipher_hd, sk->protect.iv, sk->protect.iv, 8 );
-           /* NOTE: we always recalculate the checksum because there are some
-            * test releases which calculated it wrong */
-           csum = 0;
-           for(i=pubkey_get_npkey(sk->pubkey_algo);
-                   i < pubkey_get_nskey(sk->pubkey_algo); i++ ) {
-               csum += checksum_mpi_counted_nbits( sk->skey[i] );
-               buffer = mpi_get_buffer( sk->skey[i], &nbytes, NULL );
-               cipher_sync( cipher_hd );
-               assert( !mpi_is_protected(sk->skey[i]) );
-               cipher_encrypt( cipher_hd, buffer, buffer, nbytes );
-               mpi_set_buffer( sk->skey[i], buffer, nbytes, 0 );
-               mpi_set_protect_flag( sk->skey[i] );
-               m_free( buffer );
+           print_cipher_algo_note( sk->protect.algo );
+           rc = gcry_cipher_open (&cipher_hd, sk->protect.algo,
+                                   GCRY_CIPHER_MODE_CFB,
+                                   GCRY_CIPHER_SECURE
+                                   | (sk->protect.algo >= 100 ?
+                                      0 : GCRY_CIPHER_ENABLE_SYNC) );
+            if (rc)
+              BUG();
+           if( gcry_cipher_setkey( cipher_hd, dek->key, dek->keylen ) )
+               log_info(_("WARNING: Weak key detected"
+                          " - please change passphrase again.\n"));
+           sk->protect.ivlen = gcry_cipher_get_algo_blklen(sk->protect.algo);
+           assert( sk->protect.ivlen <= DIM(sk->protect.iv) );
+           if( sk->protect.ivlen != 8 && sk->protect.ivlen != 16 )
+               BUG(); /* yes, we are very careful */
+           gcry_create_nonce (sk->protect.iv, sk->protect.ivlen);
+           gcry_cipher_setiv( cipher_hd, sk->protect.iv, sk->protect.ivlen );
+           if( sk->version >= 4 ) {
+                unsigned char *bufarr[PUBKEY_MAX_NSKEY];
+               unsigned narr[PUBKEY_MAX_NSKEY];
+               unsigned nbits[PUBKEY_MAX_NSKEY];
+               int ndata=0;
+               byte *p, *data;
+
+               for(j=0, i = pubkey_get_npkey(sk->pubkey_algo);
+                       i < pubkey_get_nskey(sk->pubkey_algo); i++, j++ ) {
+                   assert( !gcry_mpi_get_flag( sk->skey[i],
+                                                GCRYMPI_FLAG_OPAQUE ));
+
+                   if( gcry_mpi_aprint( GCRYMPI_FMT_USG, bufarr+j,
+                                         narr+j, sk->skey[i]))
+                       BUG();
+
+                   nbits[j]  = gcry_mpi_get_nbits( sk->skey[i] );
+                   ndata += narr[j] + 2;
+               }
+               for( ; j < PUBKEY_MAX_NSKEY; j++ )
+                   bufarr[j] = NULL;
+               ndata += opt.simple_sk_checksum? 2 : 20; /* for checksum */
+
+               data = xmalloc_secure ( ndata );
+               p = data;
+               for(j=0; j < PUBKEY_MAX_NSKEY && bufarr[j]; j++ ) {
+                   p[0] = nbits[j] >> 8 ;
+                   p[1] = nbits[j];
+                   p += 2;
+                   memcpy(p, bufarr[j], narr[j] );
+                   p += narr[j];
+                   xfree (bufarr[j]);
+               }
+                
+                if (opt.simple_sk_checksum) {
+                    log_info (_("generating the deprecated 16-bit checksum"
+                              " for secret key protection\n")); 
+                    csum = checksum( data, ndata-2);
+                    sk->csum = csum;
+                    *p++ =     csum >> 8;
+                    *p++ =     csum;
+                    sk->protect.sha1chk = 0;
+                }
+                else {
+                    gcry_md_hd_t h;
+
+                    if (gcry_md_open (&h, GCRY_MD_SHA1, 1))
+                        BUG(); /* algo not available */
+                    gcry_md_write (h, data, ndata - 20);
+                    gcry_md_final (h);
+                    memcpy (p, gcry_md_read (h, GCRY_MD_SHA1), 20);
+                    p += 20;
+                    gcry_md_close (h);
+                    sk->csum = csum = 0;
+                    sk->protect.sha1chk = 1;
+                }
+                assert( p == data+ndata );
+
+               gcry_cipher_encrypt( cipher_hd, data, ndata, NULL, 0 );
+               for(i = pubkey_get_npkey(sk->pubkey_algo);
+                       i < pubkey_get_nskey(sk->pubkey_algo); i++ ) {
+                   gcry_mpi_release ( sk->skey[i] );
+                   sk->skey[i] = NULL;
+               }
+               i = pubkey_get_npkey(sk->pubkey_algo);
+               sk->skey[i] = gcry_mpi_set_opaque(NULL, data, ndata*8);
+           }
+           else {
+               csum = 0;
+               for(i=pubkey_get_npkey(sk->pubkey_algo);
+                       i < pubkey_get_nskey(sk->pubkey_algo); i++ ) {
+                    byte *data;
+                   unsigned int nbits;
+
+                   csum += checksum_mpi (sk->skey[i]);
+                   if( gcry_mpi_aprint( GCRYMPI_FMT_USG, &buffer,
+                                         &nbytes, sk->skey[i] ) )
+                       BUG();
+                   gcry_cipher_sync (cipher_hd);
+                   assert (!gcry_mpi_get_flag( sk->skey[i],
+                                                GCRYMPI_FLAG_OPAQUE ));
+                    data = xmalloc (nbytes+2);
+                    nbits  = gcry_mpi_get_nbits (sk->skey[i]);
+                    assert (nbytes == (nbits + 7)/8);
+                    data[0] = nbits >> 8;
+                    data[1] = nbits;
+                   gcry_cipher_encrypt (cipher_hd, data+2, nbytes,
+                                         buffer, nbytes);
+                   xfree ( buffer );
+                    
+                    gcry_mpi_release (sk->skey[i]);
+                    sk->skey[i] = gcry_mpi_set_opaque (NULL, data,
+                                                       (nbytes+2)*8);
+               }
+               sk->csum = csum;
            }
-           sk->csum = csum;
            sk->is_protected = 1;
-           cipher_close( cipher_hd );
+           gcry_cipher_close( cipher_hd );
        }
     }
     return rc;
 }
-