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Update head to match stable 1.0

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This commit is contained in:
David Shaw 2002-06-29 13:46:34 +00:00
parent 151ee2f47b
commit 3f51f7db3d
155 changed files with 83872 additions and 37585 deletions
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109
g10/cipher.c
View file

@ -1,5 +1,5 @@
/* cipher.c - En-/De-ciphering filter
* Copyright (C) 1998, 1999, 2000 Free Software Foundation, Inc.
* Copyright (C) 1998, 1999, 2000, 2001 Free Software Foundation, Inc.
*
* This file is part of GnuPG.
*
@ -25,9 +25,9 @@
#include <errno.h>
#include <assert.h>
#include <gcrypt.h>
#include "errors.h"
#include "iobuf.h"
#include "memory.h"
#include "util.h"
#include "filter.h"
#include "packet.h"
@ -45,69 +45,69 @@ write_header( cipher_filter_context_t *cfx, IOBUF a )
PACKET pkt;
PKT_encrypted ed;
byte temp[18];
unsigned int blocksize;
unsigned int nprefix;
int rc;
int use_mdc = opt.force_mdc;
unsigned blocksize;
unsigned nprefix;
int use_mdc;
blocksize = gcry_cipher_get_algo_blklen( cfx->dek->algo );
blocksize = cipher_get_blocksize( cfx->dek->algo );
if( blocksize < 8 || blocksize > 16 )
log_fatal("unsupported blocksize %u\n", blocksize );
use_mdc = cfx->dek->use_mdc;
if( blocksize != 8 )
use_mdc = 1; /* enable it for all modern ciphers */
if( opt.rfc2440 )
use_mdc = 1; /* Hack: enable it for all modern ciphers */
/* Note: We should remove this hack as soon as a reasonable number of keys
are carrying the MDC flag. But always keep the hack for conventional
encryption */
if (opt.force_mdc)
use_mdc = 1;
if( opt.rfc2440 || opt.rfc1991 || opt.disable_mdc )
use_mdc = 0; /* override - rfc2440 does not know about MDC */
memset( &ed, 0, sizeof ed );
ed.len = cfx->datalen;
ed.extralen = blocksize+2;
ed.new_ctb = !ed.len && !opt.rfc1991;
if( use_mdc ) {
ed.mdc_method = GCRY_MD_SHA1;
cfx->mdc_hash = gcry_md_open( GCRY_MD_SHA1, 0 );
if( !cfx->mdc_hash )
BUG();
ed.mdc_method = DIGEST_ALGO_SHA1;
cfx->mdc_hash = md_open( DIGEST_ALGO_SHA1, 0 );
if ( DBG_HASHING )
gcry_md_start_debug( cfx->mdc_hash, "creatmdc" );
md_start_debug( cfx->mdc_hash, "creatmdc" );
}
{
char buf[20];
sprintf (buf, "%d %d", ed.mdc_method, cfx->dek->algo);
write_status_text (STATUS_BEGIN_ENCRYPTION, buf);
}
init_packet( &pkt );
pkt.pkttype = use_mdc? PKT_ENCRYPTED_MDC : PKT_ENCRYPTED;
pkt.pkt.encrypted = &ed;
if( build_packet( a, &pkt ))
log_bug("build_packet(ENCR_DATA) failed\n");
nprefix = blocksize;
gcry_randomize( temp, nprefix, GCRY_STRONG_RANDOM );
randomize_buffer( temp, nprefix, 1 );
temp[nprefix] = temp[nprefix-2];
temp[nprefix+1] = temp[nprefix-1];
print_cipher_algo_note( cfx->dek->algo );
if( !(cfx->cipher_hd = gcry_cipher_open( cfx->dek->algo,
GCRY_CIPHER_MODE_CFB,
GCRY_CIPHER_SECURE
| ((use_mdc || cfx->dek->algo >= 100) ?
0 : GCRY_CIPHER_ENABLE_SYNC)))
) {
/* we should never get an error here cause we already checked, that
* the algorithm is available. */
BUG();
}
cfx->cipher_hd = cipher_open( cfx->dek->algo,
use_mdc? CIPHER_MODE_CFB
: CIPHER_MODE_AUTO_CFB, 1 );
/* log_hexdump( "thekey", cfx->dek->key, cfx->dek->keylen );*/
rc = gcry_cipher_setkey( cfx->cipher_hd, cfx->dek->key, cfx->dek->keylen );
if( !rc )
rc = gcry_cipher_setiv( cfx->cipher_hd, NULL, 0 );
if( rc )
log_fatal("set key or IV failed: %s\n", gcry_strerror(rc) );
cipher_setkey( cfx->cipher_hd, cfx->dek->key, cfx->dek->keylen );
cipher_setiv( cfx->cipher_hd, NULL, 0 );
/* log_hexdump( "prefix", temp, nprefix+2 ); */
if( cfx->mdc_hash )
gcry_md_write( cfx->mdc_hash, temp, nprefix+2 );
rc = gcry_cipher_encrypt( cfx->cipher_hd, temp, nprefix+2, NULL, 0 );
if( !rc )
rc = gcry_cipher_sync( cfx->cipher_hd );
if( rc )
log_fatal("encrypt failed: %s\n", gcry_strerror(rc) );
if( cfx->mdc_hash ) /* hash the "IV" */
md_write( cfx->mdc_hash, temp, nprefix+2 );
cipher_encrypt( cfx->cipher_hd, temp, temp, nprefix+2);
cipher_sync( cfx->cipher_hd );
iobuf_write(a, temp, nprefix+2);
cfx->header=1;
}
@ -129,46 +129,39 @@ cipher_filter( void *opaque, int control,
else if( control == IOBUFCTRL_FLUSH ) { /* encrypt */
assert(a);
if( !cfx->header ) {
write_status( STATUS_BEGIN_ENCRYPTION );
write_header( cfx, a );
}
if( cfx->mdc_hash )
gcry_md_write( cfx->mdc_hash, buf, size );
rc = gcry_cipher_encrypt( cfx->cipher_hd, buf, size, NULL, 0);
if( rc )
log_fatal("encrypt failed: %s\n", gcry_strerror(rc) );
md_write( cfx->mdc_hash, buf, size );
cipher_encrypt( cfx->cipher_hd, buf, buf, size);
if( iobuf_write( a, buf, size ) )
rc = GPGERR_WRITE_FILE;
rc = G10ERR_WRITE_FILE;
}
else if( control == IOBUFCTRL_FREE ) {
if( cfx->mdc_hash ) {
byte *hash;
int hashlen = gcry_md_get_algo_dlen( gcry_md_get_algo( cfx->mdc_hash ) );
int hashlen = md_digest_length( md_get_algo( cfx->mdc_hash ) );
byte temp[22];
assert( hashlen == 20 );
/* we must hash the prefix of the MDC packet here */
temp[0] = 0xd3;
temp[1] = 0x14;
gcry_md_putc( cfx->mdc_hash, temp[0] );
gcry_md_putc( cfx->mdc_hash, temp[1] );
md_putc( cfx->mdc_hash, temp[0] );
md_putc( cfx->mdc_hash, temp[1] );
hash = gcry_md_read( cfx->mdc_hash, 0 );
md_final( cfx->mdc_hash );
hash = md_read( cfx->mdc_hash, 0 );
memcpy(temp+2, hash, 20);
rc = gcry_cipher_encrypt( cfx->cipher_hd, temp, 22, NULL, 0 );
if( rc )
log_fatal("encrypt failed: %s\n", gcry_strerror(rc) );
gcry_md_close( cfx->mdc_hash ); cfx->mdc_hash = NULL;
cipher_encrypt( cfx->cipher_hd, temp, temp, 22 );
md_close( cfx->mdc_hash ); cfx->mdc_hash = NULL;
if( iobuf_write( a, temp, 22 ) )
log_error("writing MDC packet failed\n" );
}
gcry_cipher_close(cfx->cipher_hd);
write_status( STATUS_END_ENCRYPTION );
cipher_close(cfx->cipher_hd);
}
else if( control == IOBUFCTRL_DESC ) {
*(char**)buf = "cipher_filter";
}
return rc;
}