1
0
mirror of git://git.gnupg.org/gnupg.git synced 2024-12-25 10:49:57 +01:00
gnupg/g10/misc.c
David Shaw bd5517b9e2 Move idea_cipher_warn to misc.c so gpgv.c doesn't need a stub
Remove get_temp_dir (it's in exec.c now)
Allow --delete-key (now --delete-keys, though --delete-key still works) to
delete multiple keys in one go.  This applies to
--delete-secret-key(s) and --delete-secret-and-public-key(s) as well
2002-01-09 19:59:26 +00:00

441 lines
9.7 KiB
C

/* misc.c - miscellaneous functions
* Copyright (C) 1998, 1999, 2000, 2001 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 2 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, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
*/
#include <config.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>
#ifdef HAVE_STAT
#include <sys/stat.h>
#endif
#if defined(__linux__) && defined(__alpha__) && __GLIBC__ < 2
#include <asm/sysinfo.h>
#include <asm/unistd.h>
#endif
#ifdef HAVE_SETRLIMIT
#include <time.h>
#include <sys/time.h>
#include <sys/resource.h>
#endif
#include "util.h"
#include "main.h"
#include "options.h"
#include "i18n.h"
const char *g10m_revision_string(int);
const char *g10c_revision_string(int);
const char *g10u_revision_string(int);
#ifdef __GNUC__
volatile
#endif
void
pull_in_libs(void)
{
g10m_revision_string(0);
g10c_revision_string(0);
g10u_revision_string(0);
}
#if defined(__linux__) && defined(__alpha__) && __GLIBC__ < 2
#warning using trap_unaligned
static int
setsysinfo(unsigned long op, void *buffer, unsigned long size,
int *start, void *arg, unsigned long flag)
{
return syscall(__NR_osf_setsysinfo, op, buffer, size, start, arg, flag);
}
void
trap_unaligned(void)
{
unsigned int buf[2];
buf[0] = SSIN_UACPROC;
buf[1] = UAC_SIGBUS | UAC_NOPRINT;
setsysinfo(SSI_NVPAIRS, buf, 1, 0, 0, 0);
}
#else
void
trap_unaligned(void)
{ /* dummy */
}
#endif
int
disable_core_dumps()
{
#ifdef HAVE_DOSISH_SYSTEM
return 0;
#else
#ifdef HAVE_SETRLIMIT
struct rlimit limit;
limit.rlim_cur = 0;
limit.rlim_max = 0;
if( !setrlimit( RLIMIT_CORE, &limit ) )
return 0;
if( errno != EINVAL && errno != ENOSYS )
log_fatal(_("can't disable core dumps: %s\n"), strerror(errno) );
#endif
return 1;
#endif
}
u16
checksum_u16( unsigned n )
{
u16 a;
a = (n >> 8) & 0xff;
if( opt.emulate_bugs & EMUBUG_GPGCHKSUM ) {
a |= n & 0xff;
log_debug("csum_u16 emulated for n=%u\n", n);
}
else
a += n & 0xff;
return a;
}
static u16
checksum_u16_nobug( unsigned n )
{
u16 a;
a = (n >> 8) & 0xff;
a += n & 0xff;
return a;
}
u16
checksum( byte *p, unsigned n )
{
u16 a;
for(a=0; n; n-- )
a += *p++;
return a;
}
u16
checksum_mpi( MPI a )
{
u16 csum;
byte *buffer;
unsigned nbytes;
unsigned nbits;
buffer = mpi_get_buffer( a, &nbytes, NULL );
/* some versions of gpg encode wrong values for the length of an mpi
* so that mpi_get_nbits() which counts the mpi yields another (shorter)
* value than the one store with the mpi. mpi_get_nbit_info() returns
* this stored value if it is still available.
*/
if( opt.emulate_bugs & EMUBUG_GPGCHKSUM )
nbits = 0;
else
nbits = mpi_get_nbit_info(a);
if( !nbits )
nbits = mpi_get_nbits(a);
csum = checksum_u16( nbits );
csum += checksum( buffer, nbytes );
m_free( buffer );
return csum;
}
/****************
* This is the correct function
*/
u16
checksum_mpi_counted_nbits( MPI a )
{
u16 csum;
byte *buffer;
unsigned nbytes;
unsigned nbits;
buffer = mpi_get_buffer( a, &nbytes, NULL );
nbits = mpi_get_nbits(a);
mpi_set_nbit_info(a,nbits);
csum = checksum_u16_nobug( nbits );
csum += checksum( buffer, nbytes );
m_free( buffer );
return csum;
}
u32
buffer_to_u32( const byte *buffer )
{
unsigned long a;
a = *buffer << 24;
a |= buffer[1] << 16;
a |= buffer[2] << 8;
a |= buffer[3];
return a;
}
static void
no_exp_algo(void)
{
static int did_note = 0;
if( !did_note ) {
did_note = 1;
log_info(_("Experimental algorithms should not be used!\n"));
}
}
void
print_pubkey_algo_note( int algo )
{
if( algo >= 100 && algo <= 110 )
no_exp_algo();
}
void
print_cipher_algo_note( int algo )
{
if( algo >= 100 && algo <= 110 )
no_exp_algo();
else if( algo == CIPHER_ALGO_3DES
|| algo == CIPHER_ALGO_CAST5
|| algo == CIPHER_ALGO_BLOWFISH
|| algo == CIPHER_ALGO_TWOFISH
|| algo == CIPHER_ALGO_RIJNDAEL
|| algo == CIPHER_ALGO_RIJNDAEL192
|| algo == CIPHER_ALGO_RIJNDAEL256
)
;
else {
static int did_note = 0;
if( !did_note ) {
did_note = 1;
log_info(_("this cipher algorithm is deprecated; "
"please use a more standard one!\n"));
}
}
}
void
print_digest_algo_note( int algo )
{
if( algo >= 100 && algo <= 110 )
no_exp_algo();
}
/* Return a string which is used as a kind of process ID */
const byte *
get_session_marker( size_t *rlen )
{
static byte marker[SIZEOF_UNSIGNED_LONG*2];
static int initialized;
if ( !initialized ) {
volatile ulong aa, bb; /* we really want the uninitialized value */
ulong a, b;
initialized = 1;
/* also this marker is guessable it is not easy to use this
* for a faked control packet because an attacker does not
* have enough control about the time the verification does
* take place. Of course, we can add just more random but
* than we need the random generator even for verification
* tasks - which does not make sense. */
a = aa ^ (ulong)getpid();
b = bb ^ (ulong)time(NULL);
memcpy( marker, &a, SIZEOF_UNSIGNED_LONG );
memcpy( marker+SIZEOF_UNSIGNED_LONG, &b, SIZEOF_UNSIGNED_LONG );
}
*rlen = sizeof(marker);
return marker;
}
/****************
* Wrapper around the libgcrypt function with addional checks on
* openPGP contraints for the algo ID.
*/
int
openpgp_cipher_test_algo( int algo )
{
if( algo < 0 || algo > 110 )
return G10ERR_CIPHER_ALGO;
return check_cipher_algo(algo);
}
int
openpgp_pk_test_algo( int algo, unsigned int usage_flags )
{
if( algo < 0 || algo > 110 )
return G10ERR_PUBKEY_ALGO;
return check_pubkey_algo2( algo, usage_flags );
}
int
openpgp_pk_algo_usage ( int algo )
{
int use = 0;
/* they are hardwired in gpg 1.0 */
switch ( algo ) {
case PUBKEY_ALGO_RSA:
use = PUBKEY_USAGE_SIG | PUBKEY_USAGE_ENC;
break;
case PUBKEY_ALGO_RSA_E:
use = PUBKEY_USAGE_ENC;
break;
case PUBKEY_ALGO_RSA_S:
use = PUBKEY_USAGE_SIG;
break;
case PUBKEY_ALGO_ELGAMAL_E:
use = PUBKEY_USAGE_ENC;
break;
case PUBKEY_ALGO_DSA:
use = PUBKEY_USAGE_SIG;
break;
case PUBKEY_ALGO_ELGAMAL:
use = PUBKEY_USAGE_SIG | PUBKEY_USAGE_ENC;
break;
default:
break;
}
return use;
}
int
openpgp_md_test_algo( int algo )
{
if( algo < 0 || algo > 110 )
return G10ERR_DIGEST_ALGO;
return check_digest_algo(algo);
}
int
check_permissions(const char *path,int extension,int checkonly)
{
#if defined(HAVE_STAT) && !defined(HAVE_DOSISH_SYSTEM)
char *tmppath;
struct stat statbuf;
int ret=1;
int isdir=0;
if(opt.no_perm_warn)
return 0;
if(extension && path[0]!=DIRSEP_C)
{
if(strchr(path,DIRSEP_C))
tmppath=make_filename(path,NULL);
else
tmppath=make_filename(GNUPG_LIBDIR,path,NULL);
}
else
tmppath=m_strdup(path);
/* It's okay if the file doesn't exist */
if(stat(tmppath,&statbuf)!=0)
{
ret=0;
goto end;
}
isdir=S_ISDIR(statbuf.st_mode);
/* Per-user files must be owned by the user. Extensions must be
owned by the user or root. */
if((!extension && statbuf.st_uid != getuid()) ||
(extension && statbuf.st_uid!=0 && statbuf.st_uid!=getuid()))
{
if(!checkonly)
log_info(_("Warning: unsafe ownership on %s \"%s\"\n"),
isdir?"directory":extension?"extension":"file",path);
goto end;
}
/* This works for both directories and files - basically, we don't
care what the owner permissions are, so long as the group and
other permissions are 0 for per-user files, and non-writable for
extensions. */
if((extension && (statbuf.st_mode & (S_IWGRP|S_IWOTH)) !=0) ||
(!extension && (statbuf.st_mode & (S_IRWXG|S_IRWXO)) != 0))
{
char *dir;
/* However, if the directory the directory/file is in is owned
by the user and is 700, then this is not a problem.
Theoretically, we could walk this test up to the root
directory /, but for the sake of sanity, I'm stopping at one
level down. */
dir=make_dirname(tmppath);
if(stat(dir,&statbuf)==0 && statbuf.st_uid==getuid() &&
S_ISDIR(statbuf.st_mode) && (statbuf.st_mode & (S_IRWXG|S_IRWXO))==0)
{
m_free(dir);
ret=0;
goto end;
}
m_free(dir);
if(!checkonly)
log_info(_("Warning: unsafe permissions on %s \"%s\"\n"),
isdir?"directory":extension?"extension":"file",path);
goto end;
}
ret=0;
end:
m_free(tmppath);
return ret;
#endif /* HAVE_STAT && !HAVE_DOSISH_SYSTEM */
return 0;
}
/* Special warning for the IDEA cipher */
void
idea_cipher_warn(int show)
{
static int warned=0;
if(!warned || show)
{
log_info(_("the IDEA cipher plugin is not present\n"));
log_info(_("please see http://www.gnupg.org/why-not-idea.html "
"for more information\n"));
warned=1;
}
}