mirror of
git://git.gnupg.org/gnupg.git
synced 2024-09-06 12:46:22 +02:00
326 lines
9.4 KiB
C
326 lines
9.4 KiB
C
/* create.c - Create a new crypto container
|
|
* Copyright (C) 2009 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 <http://www.gnu.org/licenses/>.
|
|
*/
|
|
|
|
#include <config.h>
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <errno.h>
|
|
#include <unistd.h>
|
|
#include <sys/stat.h>
|
|
#include <assert.h>
|
|
|
|
#include "g13.h"
|
|
#include "i18n.h"
|
|
#include "create.h"
|
|
|
|
#include "keyblob.h"
|
|
#include "backend.h"
|
|
#include "utils.h"
|
|
#include "call-gpg.h"
|
|
#include "estream.h"
|
|
|
|
/* Create a new blob with all the session keys and other meta
|
|
information which are to be stored encrypted in the crypto
|
|
container header. On success the malloced blob is stored at R_BLOB
|
|
and its length at R_BLOBLEN. On error an error code is returned
|
|
and (R_BLOB,R_BLOBLEN) are set to (NULL,0).
|
|
|
|
The format of this blob is a sequence of tag-length-value tuples.
|
|
All tuples have this format:
|
|
|
|
2 byte TAG Big endian unsigned integer (0..65535)
|
|
described by the KEYBLOB_TAG_ constants.
|
|
2 byte LENGTH Big endian unsigned integer (0..65535)
|
|
giving the length of the value.
|
|
length bytes VALUE The value described by the tag.
|
|
|
|
The first tag in a keyblob must be a BLOBVERSION. The other tags
|
|
depend on the type of the container as described by the CONTTYPE
|
|
tag. See keyblob.h for details. */
|
|
static gpg_error_t
|
|
create_new_keyblob (ctrl_t ctrl, int is_detached,
|
|
void **r_blob, size_t *r_bloblen)
|
|
{
|
|
gpg_error_t err;
|
|
unsigned char twobyte[2];
|
|
membuf_t mb;
|
|
|
|
*r_blob = NULL;
|
|
*r_bloblen = 0;
|
|
|
|
init_membuf_secure (&mb, 512);
|
|
|
|
append_tuple (&mb, KEYBLOB_TAG_BLOBVERSION, "\x01", 1);
|
|
|
|
twobyte[0] = (ctrl->conttype >> 8);
|
|
twobyte[1] = (ctrl->conttype);
|
|
append_tuple (&mb, KEYBLOB_TAG_CONTTYPE, twobyte, 2);
|
|
if (is_detached)
|
|
append_tuple (&mb, KEYBLOB_TAG_DETACHED, NULL, 0);
|
|
|
|
err = be_create_new_keys (ctrl->conttype, &mb);
|
|
if (err)
|
|
goto leave;
|
|
|
|
/* Just for testing. */
|
|
append_tuple (&mb, KEYBLOB_TAG_FILLER, "filler", 6);
|
|
|
|
*r_blob = get_membuf (&mb, r_bloblen);
|
|
if (!*r_blob)
|
|
{
|
|
err = gpg_error_from_syserror ();
|
|
*r_bloblen = 0;
|
|
}
|
|
else
|
|
log_debug ("used keyblob size is %zu\n", *r_bloblen);
|
|
|
|
leave:
|
|
xfree (get_membuf (&mb, NULL));
|
|
return err;
|
|
}
|
|
|
|
|
|
|
|
/* Encrypt the keyblob (KEYBLOB,KEYBLOBLEN) and store the result at
|
|
(R_ENCBLOB, R_ENCBLOBLEN). Returns 0 on success or an error code.
|
|
On error R_EKYBLOB is set to NULL. Depending on the keys set in
|
|
CTRL the result is a single OpenPGP binary message, a single
|
|
special OpenPGP packet encapsulating a CMS message or a
|
|
concatenation of both with the CMS packet being the last. */
|
|
static gpg_error_t
|
|
encrypt_keyblob (ctrl_t ctrl, void *keyblob, size_t keybloblen,
|
|
strlist_t keys,
|
|
void **r_encblob, size_t *r_encbloblen)
|
|
{
|
|
gpg_error_t err;
|
|
|
|
/* FIXME: For now we only implement OpenPGP. */
|
|
err = gpg_encrypt_blob (ctrl, keyblob, keybloblen, keys,
|
|
r_encblob, r_encbloblen);
|
|
|
|
return err;
|
|
}
|
|
|
|
|
|
/* Write a new file under the name FILENAME with the keyblob and an
|
|
appropriate header. This fucntion is called with a lock file in
|
|
place and after checking that the filename does not exists. */
|
|
static gpg_error_t
|
|
write_keyblob (const char *filename,
|
|
const void *keyblob, size_t keybloblen)
|
|
{
|
|
gpg_error_t err;
|
|
estream_t fp;
|
|
unsigned char packet[32];
|
|
size_t headerlen, paddinglen;
|
|
|
|
fp = es_fopen (filename, "wbx");
|
|
if (!fp)
|
|
{
|
|
err = gpg_error_from_syserror ();
|
|
log_error ("error creating new container `%s': %s\n",
|
|
filename, gpg_strerror (err));
|
|
return err;
|
|
}
|
|
|
|
/* Allow for an least 8 times larger keyblob to accommodate for
|
|
future key changes. Round it up to 4096 byte. */
|
|
headerlen = ((32 + 8 * keybloblen + 16) + 4095) / 4096 * 4096;
|
|
paddinglen = headerlen - 32 - keybloblen;
|
|
assert (paddinglen >= 16);
|
|
|
|
packet[0] = (0xc0|61); /* CTB for the private packet type 0x61. */
|
|
packet[1] = 0xff; /* 5 byte length packet, value 20. */
|
|
packet[2] = 0;
|
|
packet[3] = 0;
|
|
packet[4] = 0;
|
|
packet[5] = 26;
|
|
memcpy (packet+6, "GnuPG/G13", 10); /* Packet subtype. */
|
|
packet[16] = 1; /* G13 packet format version. */
|
|
packet[17] = 0; /* Reserved. */
|
|
packet[18] = 0; /* Reserved. */
|
|
packet[19] = 0; /* OS Flag. */
|
|
packet[20] = (headerlen >> 24); /* Total length of header. */
|
|
packet[21] = (headerlen >> 16);
|
|
packet[22] = (headerlen >> 8);
|
|
packet[23] = (headerlen);
|
|
packet[24] = 1; /* Number of header copies. */
|
|
packet[25] = 0; /* Number of header copies at the end. */
|
|
packet[26] = 0; /* Reserved. */
|
|
packet[27] = 0; /* Reserved. */
|
|
packet[28] = 0; /* Reserved. */
|
|
packet[29] = 0; /* Reserved. */
|
|
packet[30] = 0; /* Reserved. */
|
|
packet[31] = 0; /* Reserved. */
|
|
|
|
if (es_fwrite (packet, 32, 1, fp) != 1)
|
|
goto writeerr;
|
|
|
|
if (es_fwrite (keyblob, keybloblen, 1, fp) != 1)
|
|
goto writeerr;
|
|
|
|
/* Write the padding. */
|
|
packet[0] = (0xc0|61); /* CTB for Private packet type 0x61. */
|
|
packet[1] = 0xff; /* 5 byte length packet, value 20. */
|
|
packet[2] = (paddinglen-6) >> 24;
|
|
packet[3] = (paddinglen-6) >> 16;
|
|
packet[4] = (paddinglen-6) >> 8;
|
|
packet[5] = (paddinglen-6);
|
|
memcpy (packet+6, "GnuPG/PAD", 10); /* Packet subtype. */
|
|
if (es_fwrite (packet, 16, 1, fp) != 1)
|
|
goto writeerr;
|
|
memset (packet, 0, 32);
|
|
for (paddinglen-=16; paddinglen >= 32; paddinglen -= 32)
|
|
if (es_fwrite (packet, 32, 1, fp) != 1)
|
|
goto writeerr;
|
|
if (paddinglen)
|
|
if (es_fwrite (packet, paddinglen, 1, fp) != 1)
|
|
goto writeerr;
|
|
|
|
if (es_fclose (fp))
|
|
{
|
|
err = gpg_error_from_syserror ();
|
|
log_error ("error closing `%s': %s\n",
|
|
filename, gpg_strerror (err));
|
|
remove (filename);
|
|
return err;
|
|
}
|
|
|
|
return 0;
|
|
|
|
|
|
writeerr:
|
|
err = gpg_error_from_syserror ();
|
|
log_error ("error writing header to `%s': %s\n",
|
|
filename, gpg_strerror (err));
|
|
es_fclose (fp);
|
|
remove (filename);
|
|
return err;
|
|
}
|
|
|
|
|
|
|
|
/* Create a new container under the name FILENAME and intialize it
|
|
using the current settings. KEYS is a list of public keys to which
|
|
the container will be encrypted. If the file already exists an
|
|
error is returned. */
|
|
gpg_error_t
|
|
g13_create_container (ctrl_t ctrl, const char *filename, strlist_t keys)
|
|
{
|
|
gpg_error_t err;
|
|
dotlock_t lock;
|
|
void *keyblob = NULL;
|
|
size_t keybloblen;
|
|
void *enckeyblob = NULL;
|
|
size_t enckeybloblen;
|
|
char *detachedname = NULL;
|
|
int detachedisdir;
|
|
tupledesc_t tuples = NULL;
|
|
unsigned int dummy_rid;
|
|
|
|
if (!keys)
|
|
return gpg_error (GPG_ERR_NO_PUBKEY);
|
|
|
|
/* A quick check to see that no container with that name already
|
|
exists. */
|
|
if (!access (filename, F_OK))
|
|
return gpg_error (GPG_ERR_EEXIST);
|
|
|
|
/* Take a lock and proceed with the creation. If there is a lock we
|
|
immediately return an error because for creation it does not make
|
|
sense to wait. */
|
|
lock = dotlock_create (filename, 0);
|
|
if (!lock)
|
|
return gpg_error_from_syserror ();
|
|
if (dotlock_take (lock, 0))
|
|
{
|
|
err = gpg_error_from_syserror ();
|
|
goto leave;
|
|
}
|
|
else
|
|
err = 0;
|
|
|
|
/* Check again that the file does not exist. */
|
|
{
|
|
struct stat sb;
|
|
|
|
if (!stat (filename, &sb))
|
|
{
|
|
err = gpg_error (GPG_ERR_EEXIST);
|
|
goto leave;
|
|
}
|
|
}
|
|
/* And a possible detached file or directory may not exist either. */
|
|
err = be_get_detached_name (ctrl->conttype, filename,
|
|
&detachedname, &detachedisdir);
|
|
if (err)
|
|
goto leave;
|
|
if (detachedname)
|
|
{
|
|
struct stat sb;
|
|
|
|
if (!stat (detachedname, &sb))
|
|
{
|
|
err = gpg_error (GPG_ERR_EEXIST);
|
|
goto leave;
|
|
}
|
|
}
|
|
|
|
/* Create a new keyblob. */
|
|
err = create_new_keyblob (ctrl, !!detachedname, &keyblob, &keybloblen);
|
|
if (err)
|
|
goto leave;
|
|
|
|
/* Encrypt that keyblob. */
|
|
err = encrypt_keyblob (ctrl, keyblob, keybloblen, keys,
|
|
&enckeyblob, &enckeybloblen);
|
|
if (err)
|
|
goto leave;
|
|
|
|
/* Put a copy of the keyblob into a tuple structure. */
|
|
err = create_tupledesc (&tuples, keyblob, keybloblen);
|
|
if (err)
|
|
goto leave;
|
|
keyblob = NULL;
|
|
/* if (opt.verbose) */
|
|
/* dump_keyblob (tuples); */
|
|
|
|
/* Write out the header, the encrypted keyblob and some padding. */
|
|
err = write_keyblob (filename, enckeyblob, enckeybloblen);
|
|
if (err)
|
|
goto leave;
|
|
|
|
/* Create and append the container. FIXME: We should pass the
|
|
estream object in addition to the filename, so that the backend
|
|
can append the container to the g13 file. */
|
|
err = be_create_container (ctrl, ctrl->conttype, filename, -1, tuples,
|
|
&dummy_rid);
|
|
|
|
|
|
leave:
|
|
destroy_tupledesc (tuples);
|
|
xfree (detachedname);
|
|
xfree (enckeyblob);
|
|
xfree (keyblob);
|
|
dotlock_destroy (lock);
|
|
|
|
return err;
|
|
}
|