diff --git a/g10/cipher.c b/g10/cipher.c
index 409d0adef..b950d0c3f 100644
--- a/g10/cipher.c
+++ b/g10/cipher.c
@@ -1,164 +1,184 @@
/* cipher.c - En-/De-ciphering filter
* Copyright (C) 1998-2003, 2006, 2009 Free Software Foundation, Inc.
* Copyright (C) 1998-2003, 2006, 2009, 2017 Werner koch
*
* This file is part of GnuPG.
*
* 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 3 of the License, or
* (at your option) any later version.
*
* 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.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, see .
* SPDX-License-Identifier: GPL-3.0+
*/
#include
#include
#include
#include
#include
#include "gpg.h"
#include "../common/status.h"
#include "../common/iobuf.h"
#include "../common/util.h"
#include "filter.h"
#include "packet.h"
#include "options.h"
#include "main.h"
#include "../common/status.h"
#define MIN_PARTIAL_SIZE 512
static void
write_header (cipher_filter_context_t *cfx, iobuf_t a)
{
gcry_error_t err;
PACKET pkt;
PKT_encrypted ed;
byte temp[18];
unsigned int blocksize;
unsigned int nprefix;
blocksize = openpgp_cipher_get_algo_blklen (cfx->dek->algo);
if ( blocksize < 8 || blocksize > 16 )
log_fatal ("unsupported blocksize %u\n", blocksize);
memset (&ed, 0, sizeof ed);
ed.len = cfx->datalen;
ed.extralen = blocksize + 2;
ed.new_ctb = !ed.len;
if (cfx->dek->use_mdc)
{
ed.mdc_method = DIGEST_ALGO_SHA1;
gcry_md_open (&cfx->mdc_hash, DIGEST_ALGO_SHA1, 0);
if (DBG_HASHING)
gcry_md_debug (cfx->mdc_hash, "creatmdc");
}
+ else if (!opt.no_mdc_warn)
+ {
+ log_info ("WARNING: "
+ "encrypting without integrity protection is dangerous\n");
+ }
write_status_printf (STATUS_BEGIN_ENCRYPTION, "%d %d",
ed.mdc_method, cfx->dek->algo);
init_packet (&pkt);
pkt.pkttype = cfx->dek->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 );
temp[nprefix] = temp[nprefix-2];
temp[nprefix+1] = temp[nprefix-1];
print_cipher_algo_note (cfx->dek->algo);
err = openpgp_cipher_open (&cfx->cipher_hd,
cfx->dek->algo,
GCRY_CIPHER_MODE_CFB,
(GCRY_CIPHER_SECURE
| ((cfx->dek->use_mdc || cfx->dek->algo >= 100)?
0 : GCRY_CIPHER_ENABLE_SYNC)));
if (err)
{
/* We should never get an error here cause we already checked,
* that the algorithm is available. */
BUG();
}
-
/* log_hexdump ("thekey", cfx->dek->key, cfx->dek->keylen); */
gcry_cipher_setkey (cfx->cipher_hd, cfx->dek->key, cfx->dek->keylen);
gcry_cipher_setiv (cfx->cipher_hd, NULL, 0);
/* log_hexdump ("prefix", temp, nprefix+2); */
if (cfx->mdc_hash) /* Hash the "IV". */
gcry_md_write (cfx->mdc_hash, temp, nprefix+2 );
gcry_cipher_encrypt (cfx->cipher_hd, temp, nprefix+2, NULL, 0);
gcry_cipher_sync (cfx->cipher_hd);
iobuf_write (a, temp, nprefix+2);
- cfx->header = 1;
+
+ cfx->short_blklen_warn = (blocksize < 16);
+ cfx->short_blklen_count = nprefix+2;
+
+ cfx->wrote_header = 1;
}
/*
* This filter is used to en/de-cipher data with a symmetric algorithm
*/
int
cipher_filter (void *opaque, int control, iobuf_t a, byte *buf, size_t *ret_len)
{
cipher_filter_context_t *cfx = opaque;
size_t size = *ret_len;
int rc = 0;
if (control == IOBUFCTRL_UNDERFLOW) /* decrypt */
{
rc = -1; /* not yet used */
}
else if (control == IOBUFCTRL_FLUSH) /* encrypt */
{
log_assert (a);
- if (!cfx->header)
+ if (!cfx->wrote_header)
write_header (cfx, a);
if (cfx->mdc_hash)
gcry_md_write (cfx->mdc_hash, buf, size);
gcry_cipher_encrypt (cfx->cipher_hd, buf, size, NULL, 0);
+ if (cfx->short_blklen_warn)
+ {
+ cfx->short_blklen_count += size;
+ if (cfx->short_blklen_count > (150 * 1024 * 1024))
+ {
+ log_info ("WARNING: encrypting more than %d MiB with algorithm "
+ "%s should be avoided\n", 150,
+ openpgp_cipher_algo_name (cfx->dek->algo));
+ cfx->short_blklen_warn = 0; /* Don't show again. */
+ }
+ }
+
rc = iobuf_write (a, buf, size);
}
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));
byte temp[22];
log_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]);
gcry_md_final (cfx->mdc_hash);
hash = gcry_md_read (cfx->mdc_hash, 0);
memcpy(temp+2, hash, 20);
gcry_cipher_encrypt (cfx->cipher_hd, temp, 22, NULL, 0);
gcry_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);
}
else if (control == IOBUFCTRL_DESC)
{
mem2str (buf, "cipher_filter", *ret_len);
}
return rc;
}
diff --git a/g10/filter.h b/g10/filter.h
index 275608d4a..9e4b1e538 100644
--- a/g10/filter.h
+++ b/g10/filter.h
@@ -1,162 +1,163 @@
/* filter.h
* Copyright (C) 1998, 1999, 2000, 2001, 2003,
* 2005 Free Software Foundation, Inc.
*
* This file is part of GnuPG.
*
* 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 3 of the License, or
* (at your option) any later version.
*
* 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.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, see .
*/
#ifndef G10_FILTER_H
#define G10_FILTER_H
#include "../common/types.h"
#include "dek.h"
typedef struct {
gcry_md_hd_t md; /* catch all */
gcry_md_hd_t md2; /* if we want to calculate an alternate hash */
size_t maxbuf_size;
} md_filter_context_t;
typedef struct {
int refcount; /* Initialized to 1. */
/* these fields may be initialized */
int what; /* what kind of armor headers to write */
int only_keyblocks; /* skip all headers but ".... key block" */
const char *hdrlines; /* write these headerlines */
/* these fields must be initialized to zero */
int no_openpgp_data; /* output flag: "No valid OpenPGP data found" */
/* the following fields must be initialized to zero */
int inp_checked; /* set if the input has been checked */
int inp_bypass; /* set if the input is not armored */
int in_cleartext; /* clear text message */
int not_dash_escaped; /* clear text is not dash escaped */
int hashes; /* detected hash algorithms */
int faked; /* we are faking a literal data packet */
int truncated; /* number of truncated lines */
int qp_detected;
byte eol[3]; /* The end of line characters as a
zero-terminated string. Defaults
(eol[0]=='\0') to whatever the local
platform uses. */
byte *buffer; /* malloced buffer */
unsigned buffer_size; /* and size of this buffer */
unsigned buffer_len; /* used length of the buffer */
unsigned buffer_pos; /* read position */
byte radbuf[4];
int idx, idx2;
u32 crc;
int status; /* an internal state flag */
int cancel;
int any_data; /* any valid armored data seen */
int pending_lf; /* used together with faked */
} armor_filter_context_t;
struct unarmor_pump_s;
typedef struct unarmor_pump_s *UnarmorPump;
struct compress_filter_context_s {
int status;
void *opaque; /* (used for z_stream) */
byte *inbuf;
unsigned inbufsize;
byte *outbuf;
unsigned outbufsize;
int algo; /* compress algo */
int algo1hack;
int new_ctb;
void (*release)(struct compress_filter_context_s*);
};
typedef struct compress_filter_context_s compress_filter_context_t;
typedef struct {
DEK *dek;
u32 datalen;
gcry_cipher_hd_t cipher_hd;
- int header;
+ unsigned int wrote_header : 1;
+ unsigned int short_blklen_warn : 1;
+ unsigned long short_blklen_count;
gcry_md_hd_t mdc_hash;
byte enchash[20];
- int create_mdc; /* flag will be set by the cipher filter */
} cipher_filter_context_t;
typedef struct {
byte *buffer; /* malloced buffer */
unsigned buffer_size; /* and size of this buffer */
unsigned buffer_len; /* used length of the buffer */
unsigned buffer_pos; /* read position */
int truncated; /* number of truncated lines */
int not_dash_escaped;
int escape_from;
gcry_md_hd_t md;
int pending_lf;
int pending_esc;
} text_filter_context_t;
typedef struct {
char *what; /* description */
u32 last_time; /* last time reported */
unsigned long last; /* last amount reported */
unsigned long offset; /* current amount */
unsigned long total; /* total amount */
int refcount;
} progress_filter_context_t;
/* encrypt_filter_context_t defined in main.h */
/*-- mdfilter.c --*/
int md_filter( void *opaque, int control, iobuf_t a, byte *buf, size_t *ret_len);
void free_md_filter_context( md_filter_context_t *mfx );
/*-- armor.c --*/
armor_filter_context_t *new_armor_context (void);
void release_armor_context (armor_filter_context_t *afx);
int push_armor_filter (armor_filter_context_t *afx, iobuf_t iobuf);
int use_armor_filter( iobuf_t a );
UnarmorPump unarmor_pump_new (void);
void unarmor_pump_release (UnarmorPump x);
int unarmor_pump (UnarmorPump x, int c);
/*-- compress.c --*/
void push_compress_filter(iobuf_t out,compress_filter_context_t *zfx,int algo);
void push_compress_filter2(iobuf_t out,compress_filter_context_t *zfx,
int algo,int rel);
/*-- cipher.c --*/
int cipher_filter( void *opaque, int control,
iobuf_t chain, byte *buf, size_t *ret_len);
/*-- textfilter.c --*/
int text_filter( void *opaque, int control,
iobuf_t chain, byte *buf, size_t *ret_len);
int copy_clearsig_text (iobuf_t out, iobuf_t inp, gcry_md_hd_t md,
int escape_dash, int escape_from);
/*-- progress.c --*/
progress_filter_context_t *new_progress_context (void);
void release_progress_context (progress_filter_context_t *pfx);
void handle_progress (progress_filter_context_t *pfx,
iobuf_t inp, const char *name);
#endif /*G10_FILTER_H*/