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0819797911
Return the default algorithm by trying --cipher-algo/--compress-algo, then the first item in the pref list, then s2k-cipher-algo or ZIP. * sign.c (sign_file, sign_symencrypt_file), encode.c (encode_simple, encode_crypt): Call default_cipher_algo and default_compress_algo to get algorithms. * g10.c (main): Allow pref selection for compress algo with --openpgp.
809 lines
23 KiB
C
809 lines
23 KiB
C
/* encode.c - encode data
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* Copyright (C) 1998, 1999, 2000, 2001, 2002 Free Software Foundation, Inc.
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*
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* This file is part of GnuPG.
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*
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* GnuPG is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* GnuPG is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
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*/
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#include <config.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <errno.h>
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#include <assert.h>
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#include "options.h"
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#include "packet.h"
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#include "errors.h"
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#include "iobuf.h"
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#include "keydb.h"
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#include "memory.h"
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#include "util.h"
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#include "main.h"
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#include "filter.h"
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#include "trustdb.h"
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#include "i18n.h"
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#include "status.h"
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static int encode_simple( const char *filename, int mode, int compat );
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static int write_pubkey_enc_from_list( PK_LIST pk_list, DEK *dek, IOBUF out );
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/****************
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* Encode FILENAME with only the symmetric cipher. Take input from
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* stdin if FILENAME is NULL.
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*/
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int
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encode_symmetric( const char *filename )
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{
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int compat = 1;
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#if 0
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/* We don't want to use it because older gnupg version can't
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handle it and we can presume that a lot of scripts are running
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with the expert mode set. Some time in the future we might
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want to allow for it. */
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if ( opt.expert )
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compat = 0; /* PGP knows how to handle this mode. */
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#endif
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return encode_simple( filename, 1, compat );
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}
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/****************
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* Encode FILENAME as a literal data packet only. Take input from
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* stdin if FILENAME is NULL.
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*/
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int
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encode_store( const char *filename )
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{
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return encode_simple( filename, 0, 1 );
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}
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static void
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encode_sesskey( DEK *dek, DEK **ret_dek, byte *enckey )
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{
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CIPHER_HANDLE hd;
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DEK *c;
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byte buf[33];
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assert ( dek->keylen < 32 );
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c = m_alloc_clear( sizeof *c );
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c->keylen = dek->keylen;
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c->algo = dek->algo;
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make_session_key( c );
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/*log_hexdump( "thekey", c->key, c->keylen );*/
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buf[0] = c->algo;
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memcpy( buf + 1, c->key, c->keylen );
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hd = cipher_open( dek->algo, CIPHER_MODE_CFB, 1 );
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cipher_setkey( hd, dek->key, dek->keylen );
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cipher_setiv( hd, NULL, 0 );
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cipher_encrypt( hd, buf, buf, c->keylen + 1 );
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cipher_close( hd );
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memcpy( enckey, buf, c->keylen + 1 );
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wipememory( buf, sizeof buf ); /* burn key */
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*ret_dek = c;
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}
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/* We try very hard to use a MDC */
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static int
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use_mdc(PK_LIST pk_list,int algo)
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{
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/* --force-mdc overrides --disable-mdc */
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if(opt.force_mdc)
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return 1;
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if(opt.disable_mdc)
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return 0;
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/* Do the keys really support MDC? */
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if(select_mdc_from_pklist(pk_list))
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return 1;
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/* The keys don't support MDC, so now we do a bit of a hack - if any
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of the AESes or TWOFISH are in the prefs, we assume that the user
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can handle a MDC. This is valid for PGP 7, which can handle MDCs
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though it will not generate them. 2440bis allows this, by the
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way. */
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if(select_algo_from_prefs(pk_list,PREFTYPE_SYM,
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CIPHER_ALGO_AES,NULL)==CIPHER_ALGO_AES)
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return 1;
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if(select_algo_from_prefs(pk_list,PREFTYPE_SYM,
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CIPHER_ALGO_AES192,NULL)==CIPHER_ALGO_AES192)
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return 1;
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if(select_algo_from_prefs(pk_list,PREFTYPE_SYM,
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CIPHER_ALGO_AES256,NULL)==CIPHER_ALGO_AES256)
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return 1;
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if(select_algo_from_prefs(pk_list,PREFTYPE_SYM,
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CIPHER_ALGO_TWOFISH,NULL)==CIPHER_ALGO_TWOFISH)
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return 1;
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/* Last try. Use MDC for the modern ciphers. */
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if(cipher_get_blocksize(algo)!=8)
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return 1;
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return 0; /* No MDC */
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}
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static int
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encode_simple( const char *filename, int mode, int compat )
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{
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IOBUF inp, out;
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PACKET pkt;
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DEK *dek = NULL;
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PKT_plaintext *pt = NULL;
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STRING2KEY *s2k = NULL;
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byte enckey[33];
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int rc = 0;
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int seskeylen = 0;
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u32 filesize;
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cipher_filter_context_t cfx;
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armor_filter_context_t afx;
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compress_filter_context_t zfx;
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text_filter_context_t tfx;
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int do_compress = opt.compress && !opt.rfc1991;
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memset( &cfx, 0, sizeof cfx);
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memset( &afx, 0, sizeof afx);
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memset( &zfx, 0, sizeof zfx);
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memset( &tfx, 0, sizeof tfx);
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init_packet(&pkt);
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/* prepare iobufs */
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if( !(inp = iobuf_open(filename)) ) {
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log_error(_("%s: can't open: %s\n"), filename? filename: "[stdin]",
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strerror(errno) );
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return G10ERR_OPEN_FILE;
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}
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if( opt.textmode )
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iobuf_push_filter( inp, text_filter, &tfx );
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/* Due the the fact that we use don't use an IV to encrypt the
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session key we can't use the new mode with RFC1991 because
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it has no S2K salt. RFC1991 always uses simple S2K. */
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if ( opt.rfc1991 && !compat )
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compat = 1;
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cfx.dek = NULL;
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if( mode ) {
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s2k = m_alloc_clear( sizeof *s2k );
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s2k->mode = opt.rfc1991? 0:opt.s2k_mode;
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s2k->hash_algo = opt.s2k_digest_algo;
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cfx.dek = passphrase_to_dek( NULL, 0,
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default_cipher_algo(), s2k, 2, NULL );
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if( !cfx.dek || !cfx.dek->keylen ) {
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rc = G10ERR_PASSPHRASE;
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m_free(cfx.dek);
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m_free(s2k);
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iobuf_close(inp);
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log_error(_("error creating passphrase: %s\n"), g10_errstr(rc) );
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return rc;
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}
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if (!compat && s2k->mode != 1 && s2k->mode != 3) {
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compat = 1;
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log_info (_("can't use a symmetric ESK packet "
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"due to the S2K mode\n"));
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}
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if ( !compat ) {
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seskeylen = cipher_get_keylen( default_cipher_algo() ) / 8;
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encode_sesskey( cfx.dek, &dek, enckey );
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m_free( cfx.dek ); cfx.dek = dek;
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}
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cfx.dek->use_mdc=use_mdc(NULL,cfx.dek->algo);
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}
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if (opt.compress == -1 && cfx.dek && cfx.dek->use_mdc &&
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is_file_compressed(filename, &rc))
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{
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if (opt.verbose)
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log_info(_("`%s' already compressed\n"), filename);
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do_compress = 0;
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}
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if( rc || (rc = open_outfile( filename, opt.armor? 1:0, &out )) ) {
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iobuf_cancel(inp);
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m_free(cfx.dek);
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m_free(s2k);
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return rc;
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}
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if( opt.armor )
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iobuf_push_filter( out, armor_filter, &afx );
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#ifdef ENABLE_COMMENT_PACKETS
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else {
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write_comment( out, "#created by GNUPG v" VERSION " ("
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PRINTABLE_OS_NAME ")");
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if( opt.comment_string )
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write_comment( out, opt.comment_string );
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}
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#endif
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if( s2k && !opt.rfc1991 ) {
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PKT_symkey_enc *enc = m_alloc_clear( sizeof *enc + seskeylen + 1 );
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enc->version = 4;
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enc->cipher_algo = cfx.dek->algo;
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enc->s2k = *s2k;
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if ( !compat && seskeylen ) {
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enc->seskeylen = seskeylen + 1; /* algo id */
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memcpy( enc->seskey, enckey, seskeylen + 1 );
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}
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pkt.pkttype = PKT_SYMKEY_ENC;
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pkt.pkt.symkey_enc = enc;
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if( (rc = build_packet( out, &pkt )) )
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log_error("build symkey packet failed: %s\n", g10_errstr(rc) );
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m_free(enc);
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}
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if (!opt.no_literal) {
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/* setup the inner packet */
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if( filename || opt.set_filename ) {
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char *s = make_basename( opt.set_filename ? opt.set_filename
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: filename,
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iobuf_get_real_fname( inp ) );
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pt = m_alloc( sizeof *pt + strlen(s) - 1 );
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pt->namelen = strlen(s);
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memcpy(pt->name, s, pt->namelen );
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m_free(s);
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}
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else { /* no filename */
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pt = m_alloc( sizeof *pt - 1 );
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pt->namelen = 0;
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}
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}
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/* Note that PGP 5 has problems decrypting symmetrically encrypted
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data if the file length is in the inner packet. It works when
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only partial length headers are use. In the past, we always
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used partial body length here, but since PGP 2, PGP 6, and PGP
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7 need the file length, and nobody should be using PGP 5
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nowadays anyway, this is now set to the file length. Note also
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that this only applies to the RFC-1991 style symmetric
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messages, and not the RFC-2440 style. PGP 6 and 7 work with
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either partial length or fixed length with the new style
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messages. */
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if( filename && !opt.textmode ) {
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off_t tmpsize;
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if ( !(tmpsize = iobuf_get_filelength(inp)) )
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log_info(_("%s: WARNING: empty file\n"), filename );
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/* We can't encode the length of very large files because
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OpenPGP uses only 32 bit for file sizes. So if the the
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size of a file is larger than 2^32 minus some bytes for
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packet headers, we switch to partial length encoding. */
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if ( tmpsize < (IOBUF_FILELENGTH_LIMIT - 65536) )
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filesize = tmpsize;
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else
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filesize = 0;
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}
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else
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filesize = opt.set_filesize ? opt.set_filesize : 0; /* stdin */
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if (!opt.no_literal) {
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pt->timestamp = make_timestamp();
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pt->mode = opt.textmode? 't' : 'b';
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pt->len = filesize;
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pt->new_ctb = !pt->len && !opt.rfc1991;
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pt->buf = inp;
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pkt.pkttype = PKT_PLAINTEXT;
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pkt.pkt.plaintext = pt;
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cfx.datalen = filesize && !do_compress ? calc_packet_length( &pkt ) : 0;
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}
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else
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{
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cfx.datalen = filesize && !do_compress ? filesize : 0;
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pkt.pkttype = 0;
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pkt.pkt.generic = NULL;
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}
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/* register the cipher filter */
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if( mode )
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iobuf_push_filter( out, cipher_filter, &cfx );
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/* register the compress filter */
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if( do_compress )
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{
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if (cfx.dek && cfx.dek->use_mdc)
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zfx.new_ctb = 1;
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zfx.algo=default_compress_algo();
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iobuf_push_filter( out, compress_filter, &zfx );
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}
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/* do the work */
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if (!opt.no_literal) {
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if( (rc = build_packet( out, &pkt )) )
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log_error("build_packet failed: %s\n", g10_errstr(rc) );
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}
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else {
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/* user requested not to create a literal packet,
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* so we copy the plain data */
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byte copy_buffer[4096];
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int bytes_copied;
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while ((bytes_copied = iobuf_read(inp, copy_buffer, 4096)) != -1)
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if (iobuf_write(out, copy_buffer, bytes_copied) == -1) {
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rc = G10ERR_WRITE_FILE;
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log_error("copying input to output failed: %s\n", g10_errstr(rc) );
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break;
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}
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wipememory(copy_buffer, 4096); /* burn buffer */
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}
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/* finish the stuff */
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iobuf_close(inp);
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if (rc)
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iobuf_cancel(out);
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else {
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iobuf_close(out); /* fixme: check returncode */
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if (mode)
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write_status( STATUS_END_ENCRYPTION );
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}
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if (pt)
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pt->buf = NULL;
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free_packet(&pkt);
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m_free(cfx.dek);
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m_free(s2k);
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return rc;
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}
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/****************
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* Encrypt the file with the given userids (or ask if none
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* is supplied).
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*/
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int
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encode_crypt( const char *filename, STRLIST remusr )
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{
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IOBUF inp = NULL, out = NULL;
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PACKET pkt;
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PKT_plaintext *pt = NULL;
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int rc = 0, rc2 = 0;
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u32 filesize;
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cipher_filter_context_t cfx;
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armor_filter_context_t afx;
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compress_filter_context_t zfx;
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text_filter_context_t tfx;
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PK_LIST pk_list,work_list;
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int do_compress = opt.compress && !opt.rfc1991;
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memset( &cfx, 0, sizeof cfx);
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memset( &afx, 0, sizeof afx);
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memset( &zfx, 0, sizeof zfx);
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memset( &tfx, 0, sizeof tfx);
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init_packet(&pkt);
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if( (rc=build_pk_list( remusr, &pk_list, PUBKEY_USAGE_ENC)) )
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return rc;
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if(opt.pgp2) {
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for(work_list=pk_list; work_list; work_list=work_list->next)
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if(!(is_RSA(work_list->pk->pubkey_algo) &&
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nbits_from_pk(work_list->pk)<=2048))
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{
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log_info(_("you can only encrypt to RSA keys of 2048 bits or "
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"less in --pgp2 mode\n"));
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log_info(_("this message may not be usable by %s\n"),"PGP 2.x");
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opt.pgp2=0;
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break;
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}
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}
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/* prepare iobufs */
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if( !(inp = iobuf_open(filename)) ) {
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log_error(_("can't open %s: %s\n"), filename? filename: "[stdin]",
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strerror(errno) );
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rc = G10ERR_OPEN_FILE;
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goto leave;
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}
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else if( opt.verbose )
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log_info(_("reading from `%s'\n"), filename? filename: "[stdin]");
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if( opt.textmode )
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iobuf_push_filter( inp, text_filter, &tfx );
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if( (rc = open_outfile( filename, opt.armor? 1:0, &out )) )
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goto leave;
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if( opt.armor )
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iobuf_push_filter( out, armor_filter, &afx );
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#ifdef ENABLE_COMMENT_PACKETS
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else {
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write_comment( out, "#created by GNUPG v" VERSION " ("
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PRINTABLE_OS_NAME ")");
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if( opt.comment_string )
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write_comment( out, opt.comment_string );
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}
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#endif
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/* create a session key */
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cfx.dek = m_alloc_secure_clear (sizeof *cfx.dek);
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if( !opt.def_cipher_algo ) { /* try to get it from the prefs */
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cfx.dek->algo = select_algo_from_prefs(pk_list,PREFTYPE_SYM,-1,NULL);
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/* The only way select_algo_from_prefs can fail here is when
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mixing v3 and v4 keys, as v4 keys have an implicit
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preference entry for 3DES, and the pk_list cannot be empty.
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In this case, use 3DES anyway as it's the safest choice -
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perhaps the v3 key is being used in an OpenPGP
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implementation and we know that the implementation behind
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any v4 key can handle 3DES. */
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if( cfx.dek->algo == -1 ) {
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cfx.dek->algo = CIPHER_ALGO_3DES;
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if( opt.pgp2 ) {
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log_info(_("unable to use the IDEA cipher for all of the keys "
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"you are encrypting to.\n"));
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log_info(_("this message may not be usable by %s\n"),"PGP 2.x");
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opt.pgp2=0;
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}
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}
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}
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else {
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if(!opt.expert &&
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select_algo_from_prefs(pk_list,PREFTYPE_SYM,
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opt.def_cipher_algo,NULL)!=opt.def_cipher_algo)
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log_info(_("forcing symmetric cipher %s (%d) "
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"violates recipient preferences\n"),
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cipher_algo_to_string(opt.def_cipher_algo),
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opt.def_cipher_algo);
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cfx.dek->algo = opt.def_cipher_algo;
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}
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|
|
cfx.dek->use_mdc=use_mdc(pk_list,cfx.dek->algo);
|
|
|
|
/* Only do the is-file-already-compressed check if we are using a
|
|
MDC. This forces compressed files to be re-compressed if we do
|
|
not have a MDC to give some protection against chosen
|
|
ciphertext attacks. */
|
|
|
|
if (opt.compress == -1 && cfx.dek->use_mdc &&
|
|
is_file_compressed(filename, &rc2) )
|
|
{
|
|
if (opt.verbose)
|
|
log_info(_("`%s' already compressed\n"), filename);
|
|
do_compress = 0;
|
|
}
|
|
if (rc2)
|
|
{
|
|
rc = rc2;
|
|
goto leave;
|
|
}
|
|
|
|
make_session_key( cfx.dek );
|
|
if( DBG_CIPHER )
|
|
log_hexdump("DEK is: ", cfx.dek->key, cfx.dek->keylen );
|
|
|
|
rc = write_pubkey_enc_from_list( pk_list, cfx.dek, out );
|
|
if( rc )
|
|
goto leave;
|
|
|
|
if (!opt.no_literal) {
|
|
/* setup the inner packet */
|
|
if( filename || opt.set_filename ) {
|
|
char *s = make_basename( opt.set_filename ? opt.set_filename
|
|
: filename,
|
|
iobuf_get_real_fname( inp ) );
|
|
pt = m_alloc( sizeof *pt + strlen(s) - 1 );
|
|
pt->namelen = strlen(s);
|
|
memcpy(pt->name, s, pt->namelen );
|
|
m_free(s);
|
|
}
|
|
else { /* no filename */
|
|
pt = m_alloc( sizeof *pt - 1 );
|
|
pt->namelen = 0;
|
|
}
|
|
}
|
|
|
|
if( filename && !opt.textmode ) {
|
|
off_t tmpsize;
|
|
|
|
if ( !(tmpsize = iobuf_get_filelength(inp)) )
|
|
log_info(_("%s: WARNING: empty file\n"), filename );
|
|
/* We can't encode the length of very large files because
|
|
OpenPGP uses only 32 bit for file sizes. So if the the
|
|
size of a file is larger than 2^32 minus some bytes for
|
|
packet headers, we switch to partial length encoding. */
|
|
if ( tmpsize < (IOBUF_FILELENGTH_LIMIT - 65536) )
|
|
filesize = tmpsize;
|
|
else
|
|
filesize = 0;
|
|
}
|
|
else
|
|
filesize = opt.set_filesize ? opt.set_filesize : 0; /* stdin */
|
|
|
|
if (!opt.no_literal) {
|
|
pt->timestamp = make_timestamp();
|
|
pt->mode = opt.textmode ? 't' : 'b';
|
|
pt->len = filesize;
|
|
pt->new_ctb = !pt->len && !opt.rfc1991;
|
|
pt->buf = inp;
|
|
pkt.pkttype = PKT_PLAINTEXT;
|
|
pkt.pkt.plaintext = pt;
|
|
cfx.datalen = filesize && !do_compress? calc_packet_length( &pkt ) : 0;
|
|
}
|
|
else
|
|
cfx.datalen = filesize && !do_compress ? filesize : 0;
|
|
|
|
/* register the cipher filter */
|
|
iobuf_push_filter( out, cipher_filter, &cfx );
|
|
|
|
/* register the compress filter */
|
|
if( do_compress ) {
|
|
int compr_algo = opt.def_compress_algo;
|
|
|
|
if(compr_algo==-1)
|
|
{
|
|
if((compr_algo=
|
|
select_algo_from_prefs(pk_list,PREFTYPE_ZIP,-1,NULL))==-1)
|
|
compr_algo=DEFAULT_COMPRESS_ALGO;
|
|
/* Theoretically impossible to get here since uncompressed
|
|
is implicit. */
|
|
}
|
|
else if(!opt.expert &&
|
|
select_algo_from_prefs(pk_list,PREFTYPE_ZIP,
|
|
compr_algo,NULL)!=compr_algo)
|
|
log_info(_("forcing compression algorithm %s (%d) "
|
|
"violates recipient preferences\n"),
|
|
compress_algo_to_string(compr_algo),compr_algo);
|
|
|
|
/* algo 0 means no compression */
|
|
if( compr_algo )
|
|
{
|
|
if (cfx.dek && cfx.dek->use_mdc)
|
|
zfx.new_ctb = 1;
|
|
zfx.algo = compr_algo;
|
|
iobuf_push_filter( out, compress_filter, &zfx );
|
|
}
|
|
}
|
|
|
|
/* do the work */
|
|
if (!opt.no_literal) {
|
|
if( (rc = build_packet( out, &pkt )) )
|
|
log_error("build_packet failed: %s\n", g10_errstr(rc) );
|
|
}
|
|
else {
|
|
/* user requested not to create a literal packet, so we copy
|
|
the plain data */
|
|
byte copy_buffer[4096];
|
|
int bytes_copied;
|
|
while ((bytes_copied = iobuf_read(inp, copy_buffer, 4096)) != -1)
|
|
if (iobuf_write(out, copy_buffer, bytes_copied) == -1) {
|
|
rc = G10ERR_WRITE_FILE;
|
|
log_error("copying input to output failed: %s\n",
|
|
g10_errstr(rc) );
|
|
break;
|
|
}
|
|
wipememory(copy_buffer, 4096); /* burn buffer */
|
|
}
|
|
|
|
/* finish the stuff */
|
|
leave:
|
|
iobuf_close(inp);
|
|
if( rc )
|
|
iobuf_cancel(out);
|
|
else {
|
|
iobuf_close(out); /* fixme: check returncode */
|
|
write_status( STATUS_END_ENCRYPTION );
|
|
}
|
|
if( pt )
|
|
pt->buf = NULL;
|
|
free_packet(&pkt);
|
|
m_free(cfx.dek);
|
|
release_pk_list( pk_list );
|
|
return rc;
|
|
}
|
|
|
|
|
|
|
|
|
|
/****************
|
|
* Filter to do a complete public key encryption.
|
|
*/
|
|
int
|
|
encrypt_filter( void *opaque, int control,
|
|
IOBUF a, byte *buf, size_t *ret_len)
|
|
{
|
|
size_t size = *ret_len;
|
|
encrypt_filter_context_t *efx = opaque;
|
|
int rc=0;
|
|
|
|
if( control == IOBUFCTRL_UNDERFLOW ) { /* decrypt */
|
|
BUG(); /* not used */
|
|
}
|
|
else if( control == IOBUFCTRL_FLUSH ) { /* encrypt */
|
|
if( !efx->header_okay ) {
|
|
efx->cfx.dek = m_alloc_secure_clear( sizeof *efx->cfx.dek );
|
|
|
|
if( !opt.def_cipher_algo ) { /* try to get it from the prefs */
|
|
efx->cfx.dek->algo =
|
|
select_algo_from_prefs(efx->pk_list,PREFTYPE_SYM,-1,NULL);
|
|
if( efx->cfx.dek->algo == -1 ) {
|
|
/* because 3DES is implicitly in the prefs, this can only
|
|
* happen if we do not have any public keys in the list */
|
|
efx->cfx.dek->algo = DEFAULT_CIPHER_ALGO;
|
|
}
|
|
}
|
|
else {
|
|
if(!opt.expert &&
|
|
select_algo_from_prefs(efx->pk_list,PREFTYPE_SYM,
|
|
opt.def_cipher_algo,
|
|
NULL)!=opt.def_cipher_algo)
|
|
log_info(_("forcing symmetric cipher %s (%d) "
|
|
"violates recipient preferences\n"),
|
|
cipher_algo_to_string(opt.def_cipher_algo),
|
|
opt.def_cipher_algo);
|
|
|
|
efx->cfx.dek->algo = opt.def_cipher_algo;
|
|
}
|
|
|
|
efx->cfx.dek->use_mdc = use_mdc(efx->pk_list,efx->cfx.dek->algo);
|
|
|
|
make_session_key( efx->cfx.dek );
|
|
if( DBG_CIPHER )
|
|
log_hexdump("DEK is: ",
|
|
efx->cfx.dek->key, efx->cfx.dek->keylen );
|
|
|
|
rc = write_pubkey_enc_from_list( efx->pk_list, efx->cfx.dek, a );
|
|
if( rc )
|
|
return rc;
|
|
|
|
iobuf_push_filter( a, cipher_filter, &efx->cfx );
|
|
|
|
efx->header_okay = 1;
|
|
}
|
|
rc = iobuf_write( a, buf, size );
|
|
|
|
}
|
|
else if( control == IOBUFCTRL_FREE ) {
|
|
}
|
|
else if( control == IOBUFCTRL_DESC ) {
|
|
*(char**)buf = "encrypt_filter";
|
|
}
|
|
return rc;
|
|
}
|
|
|
|
|
|
/****************
|
|
* Write pubkey-enc packets from the list of PKs to OUT.
|
|
*/
|
|
static int
|
|
write_pubkey_enc_from_list( PK_LIST pk_list, DEK *dek, IOBUF out )
|
|
{
|
|
PACKET pkt;
|
|
PKT_public_key *pk;
|
|
PKT_pubkey_enc *enc;
|
|
int rc;
|
|
|
|
for( ; pk_list; pk_list = pk_list->next ) {
|
|
MPI frame;
|
|
|
|
pk = pk_list->pk;
|
|
|
|
print_pubkey_algo_note( pk->pubkey_algo );
|
|
enc = m_alloc_clear( sizeof *enc );
|
|
enc->pubkey_algo = pk->pubkey_algo;
|
|
keyid_from_pk( pk, enc->keyid );
|
|
enc->throw_keyid = (opt.throw_keyid || (pk_list->flags&1));
|
|
|
|
if(opt.throw_keyid && (opt.pgp2 || opt.pgp6 || opt.pgp7))
|
|
{
|
|
log_info(_("you may not use %s while in %s mode\n"),
|
|
"--throw-keyid",
|
|
opt.pgp2?"--pgp2":opt.pgp6?"--pgp6":"--pgp7");
|
|
|
|
log_info(_("this message may not be usable by %s\n"),
|
|
opt.pgp2?"PGP 2.x":opt.pgp6?"PGP 6.x":"PGP 7.x");
|
|
|
|
opt.pgp2=opt.pgp6=opt.pgp7=0;
|
|
}
|
|
|
|
/* Okay, what's going on: We have the session key somewhere in
|
|
* the structure DEK and want to encode this session key in
|
|
* an integer value of n bits. pubkey_nbits gives us the
|
|
* number of bits we have to use. We then encode the session
|
|
* key in some way and we get it back in the big intger value
|
|
* FRAME. Then we use FRAME, the public key PK->PKEY and the
|
|
* algorithm number PK->PUBKEY_ALGO and pass it to pubkey_encrypt
|
|
* which returns the encrypted value in the array ENC->DATA.
|
|
* This array has a size which depends on the used algorithm
|
|
* (e.g. 2 for ElGamal). We don't need frame anymore because we
|
|
* have everything now in enc->data which is the passed to
|
|
* build_packet()
|
|
*/
|
|
frame = encode_session_key( dek, pubkey_nbits( pk->pubkey_algo,
|
|
pk->pkey ) );
|
|
rc = pubkey_encrypt( pk->pubkey_algo, enc->data, frame, pk->pkey );
|
|
mpi_free( frame );
|
|
if( rc )
|
|
log_error("pubkey_encrypt failed: %s\n", g10_errstr(rc) );
|
|
else {
|
|
if( opt.verbose ) {
|
|
char *ustr = get_user_id_string_printable (enc->keyid);
|
|
log_info(_("%s/%s encrypted for: \"%s\"\n"),
|
|
pubkey_algo_to_string(enc->pubkey_algo),
|
|
cipher_algo_to_string(dek->algo), ustr );
|
|
m_free(ustr);
|
|
}
|
|
/* and write it */
|
|
init_packet(&pkt);
|
|
pkt.pkttype = PKT_PUBKEY_ENC;
|
|
pkt.pkt.pubkey_enc = enc;
|
|
rc = build_packet( out, &pkt );
|
|
if( rc )
|
|
log_error("build_packet(pubkey_enc) failed: %s\n", g10_errstr(rc));
|
|
}
|
|
free_pubkey_enc(enc);
|
|
if( rc )
|
|
return rc;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
void
|
|
encode_crypt_files(int nfiles, char **files, STRLIST remusr)
|
|
{
|
|
int rc = 0;
|
|
|
|
if (opt.outfile)
|
|
{
|
|
log_error(_("--output doesn't work for this command\n"));
|
|
return;
|
|
}
|
|
|
|
if (!nfiles)
|
|
{
|
|
char line[2048];
|
|
unsigned int lno = 0;
|
|
while ( fgets(line, DIM(line), stdin) )
|
|
{
|
|
lno++;
|
|
if (!*line || line[strlen(line)-1] != '\n')
|
|
{
|
|
log_error("input line %u too long or missing LF\n", lno);
|
|
return;
|
|
}
|
|
line[strlen(line)-1] = '\0';
|
|
print_file_status(STATUS_FILE_START, line, 2);
|
|
if ( (rc = encode_crypt(line, remusr)) )
|
|
log_error("%s: encryption failed: %s\n",
|
|
print_fname_stdin(line), g10_errstr(rc) );
|
|
write_status( STATUS_FILE_DONE );
|
|
}
|
|
}
|
|
else
|
|
{
|
|
while (nfiles--)
|
|
{
|
|
print_file_status(STATUS_FILE_START, *files, 2);
|
|
if ( (rc = encode_crypt(*files, remusr)) )
|
|
log_error("%s: encryption failed: %s\n",
|
|
print_fname_stdin(*files), g10_errstr(rc) );
|
|
write_status( STATUS_FILE_DONE );
|
|
files++;
|
|
}
|
|
}
|
|
}
|