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gnupg/g10/keyid.c
Werner Koch 3627123dc8 Use inline functions to convert buffer data to scalars.
* include/host2net.h (buf16_to_ulong, buf16_to_uint): New.
(buf16_to_ushort, buf16_to_u16): New.
(buf32_to_size_t, buf32_to_ulong, buf32_to_uint, buf32_to_u32): New.
--

This fixes sign extension on shift problems.  Hanno Böck found a case
with an invalid read due to this problem.  To fix that almost all uses
of "<< 24" and "<< 8" are changed by this patch to use an inline
function from host2net.h.

(back ported from commit 2183683bd633818dd031b090b5530951de76f392)

Signed-off-by: Werner Koch <wk@gnupg.org>
2015-02-12 20:34:44 +01:00

826 lines
18 KiB
C

/* keyid.c - key ID and fingerprint handling
* Copyright (C) 1998, 1999, 2000, 2001, 2003,
* 2004, 2006 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 <time.h>
#include <assert.h>
#include "gpg.h"
#include "util.h"
#include "main.h"
#include "packet.h"
#include "options.h"
#include "keydb.h"
#include "i18n.h"
#include "rmd160.h"
#include "host2net.h"
int
pubkey_letter( int algo )
{
switch( algo ) {
case PUBKEY_ALGO_RSA: return 'R' ;
case PUBKEY_ALGO_RSA_E: return 'r' ;
case PUBKEY_ALGO_RSA_S: return 's' ;
case PUBKEY_ALGO_ELGAMAL_E: return 'g';
case PUBKEY_ALGO_ELGAMAL: return 'G' ;
case PUBKEY_ALGO_DSA: return 'D' ;
case PUBKEY_ALGO_ECDSA: return 'E' ; /* ECC DSA (sign only) */
case PUBKEY_ALGO_ECDH: return 'e' ; /* ECC DH (encrypt only) */
default: return '?';
}
}
/* This function is useful for v4 fingerprints and v3 or v4 key
signing. */
void
hash_public_key( gcry_md_hd_t md, PKT_public_key *pk )
{
unsigned int n = 6;
unsigned int nn[PUBKEY_MAX_NPKEY];
byte *pp[PUBKEY_MAX_NPKEY];
int i;
unsigned int nbits;
size_t nbytes;
int npkey = pubkey_get_npkey (pk->pubkey_algo);
/* Two extra bytes for the expiration date in v3 */
if(pk->version<4)
n+=2;
if (npkey==0 && pk->pkey[0]
&& gcry_mpi_get_flag (pk->pkey[0], GCRYMPI_FLAG_OPAQUE))
{
pp[0] = gcry_mpi_get_opaque (pk->pkey[0], &nbits);
nn[0] = (nbits+7)/8;
n+=nn[0];
}
else
for(i=0; i < npkey; i++ )
{
if (gcry_mpi_print (GCRYMPI_FMT_PGP, NULL, 0, &nbytes, pk->pkey[i]))
BUG ();
pp[i] = xmalloc (nbytes);
if (gcry_mpi_print (GCRYMPI_FMT_PGP, pp[i], nbytes,
&nbytes, pk->pkey[i]))
BUG ();
nn[i] = nbytes;
n += nn[i];
}
gcry_md_putc ( md, 0x99 ); /* ctb */
/* What does it mean if n is greater than than 0xFFFF ? */
gcry_md_putc ( md, n >> 8 ); /* 2 byte length header */
gcry_md_putc ( md, n );
gcry_md_putc ( md, pk->version );
gcry_md_putc ( md, pk->timestamp >> 24 );
gcry_md_putc ( md, pk->timestamp >> 16 );
gcry_md_putc ( md, pk->timestamp >> 8 );
gcry_md_putc ( md, pk->timestamp );
if(pk->version<4)
{
u16 days=0;
if(pk->expiredate)
days=(u16)((pk->expiredate - pk->timestamp) / 86400L);
gcry_md_putc ( md, days >> 8 );
gcry_md_putc ( md, days );
}
gcry_md_putc ( md, pk->pubkey_algo );
if(npkey==0 && pk->pkey[0]
&& gcry_mpi_get_flag (pk->pkey[0], GCRYMPI_FLAG_OPAQUE))
{
gcry_md_write (md, pp[0], nn[0]);
}
else
for(i=0; i < npkey; i++ )
{
gcry_md_write ( md, pp[i], nn[i] );
xfree(pp[i]);
}
}
static gcry_md_hd_t
do_fingerprint_md( PKT_public_key *pk )
{
gcry_md_hd_t md;
if (gcry_md_open (&md, DIGEST_ALGO_SHA1, 0))
BUG ();
hash_public_key(md,pk);
gcry_md_final( md );
return md;
}
static gcry_md_hd_t
do_fingerprint_md_sk( PKT_secret_key *sk )
{
PKT_public_key pk;
int npkey = pubkey_get_npkey( sk->pubkey_algo ); /* npkey is correct! */
int i;
if(npkey==0)
return NULL;
pk.pubkey_algo = sk->pubkey_algo;
pk.version = sk->version;
pk.timestamp = sk->timestamp;
pk.expiredate = sk->expiredate;
pk.pubkey_algo = sk->pubkey_algo;
for( i=0; i < npkey; i++ )
pk.pkey[i] = sk->skey[i];
return do_fingerprint_md( &pk );
}
u32
v3_keyid (gcry_mpi_t a, u32 *ki)
{
byte *buffer, *p;
size_t nbytes;
if (gcry_mpi_print (GCRYMPI_FMT_USG, NULL, 0, &nbytes, a ))
BUG ();
/* fixme: allocate it on the stack */
buffer = xmalloc (nbytes);
if (gcry_mpi_print( GCRYMPI_FMT_USG, buffer, nbytes, NULL, a ))
BUG ();
if (nbytes < 8) /* oops */
ki[0] = ki[1] = 0;
else
{
p = buffer + nbytes - 8;
ki[0] = buf32_to_u32 (p);
p += 4;
ki[1] = buf32_to_u32 (p);
}
xfree (buffer);
return ki[1];
}
size_t
keystrlen(void)
{
switch(opt.keyid_format)
{
case KF_SHORT:
return 8;
case KF_LONG:
return 16;
case KF_0xSHORT:
return 10;
case KF_0xLONG:
return 18;
default:
BUG();
}
}
const char *
keystr(u32 *keyid)
{
static char keyid_str[19];
switch(opt.keyid_format)
{
case KF_SHORT:
sprintf(keyid_str,"%08lX",(ulong)keyid[1]);
break;
case KF_LONG:
if(keyid[0])
sprintf(keyid_str,"%08lX%08lX",(ulong)keyid[0],(ulong)keyid[1]);
else
sprintf(keyid_str,"%08lX",(ulong)keyid[1]);
break;
case KF_0xSHORT:
sprintf(keyid_str,"0x%08lX",(ulong)keyid[1]);
break;
case KF_0xLONG:
if(keyid[0])
sprintf(keyid_str,"0x%08lX%08lX",(ulong)keyid[0],(ulong)keyid[1]);
else
sprintf(keyid_str,"0x%08lX",(ulong)keyid[1]);
break;
default:
BUG();
}
return keyid_str;
}
const char *
keystr_from_pk(PKT_public_key *pk)
{
keyid_from_pk(pk,NULL);
return keystr(pk->keyid);
}
const char *
keystr_from_sk(PKT_secret_key *sk)
{
keyid_from_sk(sk,NULL);
return keystr(sk->keyid);
}
const char *
keystr_from_desc(KEYDB_SEARCH_DESC *desc)
{
switch(desc->mode)
{
case KEYDB_SEARCH_MODE_LONG_KID:
case KEYDB_SEARCH_MODE_SHORT_KID:
return keystr(desc->u.kid);
case KEYDB_SEARCH_MODE_FPR20:
{
u32 keyid[2];
keyid[0] = buf32_to_u32 (desc->u.fpr+12);
keyid[1] = buf32_to_u32 (desc->u.fpr+16);
return keystr(keyid);
}
case KEYDB_SEARCH_MODE_FPR16:
return "?v3 fpr?";
default:
BUG();
}
}
/****************
* Get the keyid from the secret key and put it into keyid
* if this is not NULL. Return the 32 low bits of the keyid.
*/
u32
keyid_from_sk( PKT_secret_key *sk, u32 *keyid )
{
u32 lowbits;
u32 dummy_keyid[2];
if( !keyid )
keyid = dummy_keyid;
if( sk->keyid[0] || sk->keyid[1] )
{
keyid[0] = sk->keyid[0];
keyid[1] = sk->keyid[1];
lowbits = keyid[1];
}
else if( sk->version < 4 )
{
if( is_RSA(sk->pubkey_algo) )
{
lowbits = (pubkey_get_npkey (sk->pubkey_algo) ?
v3_keyid( sk->skey[0], keyid ) : 0); /* Take n. */
sk->keyid[0]=keyid[0];
sk->keyid[1]=keyid[1];
}
else
sk->keyid[0]=sk->keyid[1]=keyid[0]=keyid[1]=lowbits=0xFFFFFFFF;
}
else
{
const byte *dp;
gcry_md_hd_t md;
md = do_fingerprint_md_sk(sk);
if(md)
{
dp = gcry_md_read (md, 0);
keyid[0] = buf32_to_u32 (dp+12);
keyid[1] = buf32_to_u32 (dp+16);
lowbits = keyid[1];
gcry_md_close (md);
sk->keyid[0] = keyid[0];
sk->keyid[1] = keyid[1];
}
else
sk->keyid[0]=sk->keyid[1]=keyid[0]=keyid[1]=lowbits=0xFFFFFFFF;
}
return lowbits;
}
/****************
* Get the keyid from the public key and put it into keyid
* if this is not NULL. Return the 32 low bits of the keyid.
*/
u32
keyid_from_pk( PKT_public_key *pk, u32 *keyid )
{
u32 lowbits;
u32 dummy_keyid[2];
if( !keyid )
keyid = dummy_keyid;
if( pk->keyid[0] || pk->keyid[1] )
{
keyid[0] = pk->keyid[0];
keyid[1] = pk->keyid[1];
lowbits = keyid[1];
}
else if( pk->version < 4 )
{
if( is_RSA(pk->pubkey_algo) )
{
lowbits = (pubkey_get_npkey (pk->pubkey_algo) ?
v3_keyid ( pk->pkey[0], keyid ) : 0); /* From n. */
pk->keyid[0] = keyid[0];
pk->keyid[1] = keyid[1];
}
else
pk->keyid[0]=pk->keyid[1]=keyid[0]=keyid[1]=lowbits=0xFFFFFFFF;
}
else
{
const byte *dp;
gcry_md_hd_t md;
md = do_fingerprint_md(pk);
if(md)
{
dp = gcry_md_read ( md, 0 );
keyid[0] = buf32_to_u32 (dp+12);
keyid[1] = buf32_to_u32 (dp+16);
lowbits = keyid[1];
gcry_md_close (md);
pk->keyid[0] = keyid[0];
pk->keyid[1] = keyid[1];
}
else
pk->keyid[0]=pk->keyid[1]=keyid[0]=keyid[1]=lowbits=0xFFFFFFFF;
}
return lowbits;
}
/****************
* Get the keyid from the fingerprint. This function is simple for most
* keys, but has to do a keylookup for old stayle keys.
*/
u32
keyid_from_fingerprint( const byte *fprint, size_t fprint_len, u32 *keyid )
{
u32 dummy_keyid[2];
if( !keyid )
keyid = dummy_keyid;
if( fprint_len != 20 ) {
/* This is special as we have to lookup the key first */
PKT_public_key pk;
int rc;
memset( &pk, 0, sizeof pk );
rc = get_pubkey_byfprint( &pk, fprint, fprint_len );
if( rc ) {
log_error("Oops: keyid_from_fingerprint: no pubkey\n");
keyid[0] = 0;
keyid[1] = 0;
}
else
keyid_from_pk( &pk, keyid );
}
else {
const byte *dp = fprint;
keyid[0] = buf32_to_u32 (dp+12);
keyid[1] = buf32_to_u32 (dp+16);
}
return keyid[1];
}
u32
keyid_from_sig( PKT_signature *sig, u32 *keyid )
{
if( keyid ) {
keyid[0] = sig->keyid[0];
keyid[1] = sig->keyid[1];
}
return sig->keyid[1];
}
byte *
namehash_from_uid(PKT_user_id *uid)
{
if (!uid->namehash)
{
uid->namehash = xmalloc (20);
if(uid->attrib_data)
rmd160_hash_buffer (uid->namehash, uid->attrib_data, uid->attrib_len);
else
rmd160_hash_buffer (uid->namehash, uid->name, uid->len);
}
return uid->namehash;
}
/****************
* return the number of bits used in the pk
*/
unsigned
nbits_from_pk( PKT_public_key *pk )
{
return pubkey_nbits( pk->pubkey_algo, pk->pkey );
}
/****************
* return the number of bits used in the sk
*/
unsigned
nbits_from_sk( PKT_secret_key *sk )
{
return pubkey_nbits( sk->pubkey_algo, sk->skey );
}
static const char *
mk_datestr (char *buffer, time_t atime)
{
struct tm *tp;
if ( atime < 0 ) /* 32 bit time_t and after 2038-01-19 */
strcpy (buffer, "????" "-??" "-??"); /* mark this as invalid */
else {
tp = gmtime (&atime);
sprintf (buffer,"%04d-%02d-%02d",
1900+tp->tm_year, tp->tm_mon+1, tp->tm_mday );
}
return buffer;
}
/****************
* return a string with the creation date of the pk
* Note: this is alloced in a static buffer.
* Format is: yyyy-mm-dd
*/
const char *
datestr_from_pk( PKT_public_key *pk )
{
static char buffer[11+5];
time_t atime = pk->timestamp;
return mk_datestr (buffer, atime);
}
const char *
datestr_from_sk( PKT_secret_key *sk )
{
static char buffer[11+5];
time_t atime = sk->timestamp;
return mk_datestr (buffer, atime);
}
const char *
datestr_from_sig( PKT_signature *sig )
{
static char buffer[11+5];
time_t atime = sig->timestamp;
return mk_datestr (buffer, atime);
}
const char *
expirestr_from_pk( PKT_public_key *pk )
{
static char buffer[11+5];
time_t atime;
if( !pk->expiredate )
return _("never ");
atime = pk->expiredate;
return mk_datestr (buffer, atime);
}
const char *
expirestr_from_sk( PKT_secret_key *sk )
{
static char buffer[11+5];
time_t atime;
if( !sk->expiredate )
return _("never ");
atime = sk->expiredate;
return mk_datestr (buffer, atime);
}
const char *
expirestr_from_sig( PKT_signature *sig )
{
static char buffer[11+5];
time_t atime;
if(!sig->expiredate)
return _("never ");
atime=sig->expiredate;
return mk_datestr (buffer, atime);
}
const char *
revokestr_from_pk( PKT_public_key *pk )
{
static char buffer[11+5];
time_t atime;
if(!pk->revoked.date)
return _("never ");
atime=pk->revoked.date;
return mk_datestr (buffer, atime);
}
const char *
usagestr_from_pk( PKT_public_key *pk )
{
static char buffer[10];
int i = 0;
unsigned int use = pk->pubkey_usage;
if ( use & PUBKEY_USAGE_SIG )
buffer[i++] = 'S';
if ( use & PUBKEY_USAGE_CERT )
buffer[i++] = 'C';
if ( use & PUBKEY_USAGE_ENC )
buffer[i++] = 'E';
if ( (use & PUBKEY_USAGE_AUTH) )
buffer[i++] = 'A';
while (i < 4)
buffer[i++] = ' ';
buffer[i] = 0;
return buffer;
}
const char *
colon_strtime (u32 t)
{
static char buf[20];
if (!t)
return "";
snprintf (buf, sizeof buf, "%lu", (ulong)t);
return buf;
}
const char *
colon_datestr_from_pk (PKT_public_key *pk)
{
static char buf[20];
snprintf (buf, sizeof buf, "%lu", (ulong)pk->timestamp);
return buf;
}
const char *
colon_datestr_from_sk (PKT_secret_key *sk)
{
static char buf[20];
snprintf (buf, sizeof buf, "%lu", (ulong)sk->timestamp);
return buf;
}
const char *
colon_datestr_from_sig (PKT_signature *sig)
{
static char buf[20];
snprintf (buf, sizeof buf, "%lu", (ulong)sig->timestamp);
return buf;
}
const char *
colon_expirestr_from_sig (PKT_signature *sig)
{
static char buf[20];
if (!sig->expiredate)
return "";
snprintf (buf, sizeof buf,"%lu", (ulong)sig->expiredate);
return buf;
}
/**************** .
* Return a byte array with the fingerprint for the given PK/SK
* The length of the array is returned in ret_len. Caller must free
* the array or provide an array of length MAX_FINGERPRINT_LEN.
*/
byte *
fingerprint_from_pk( PKT_public_key *pk, byte *array, size_t *ret_len )
{
byte *buf;
const byte *dp;
size_t len, nbytes;
int i;
if ( pk->version < 4 )
{
if ( is_RSA(pk->pubkey_algo) && opt.flags.allow_weak_digest_algos)
{
/* RSA in version 3 packets is special. */
gcry_md_hd_t md;
if (gcry_md_open (&md, DIGEST_ALGO_MD5, 0))
BUG ();
if ( pubkey_get_npkey (pk->pubkey_algo) > 1 )
{
for (i=0; i < 2; i++)
{
if (gcry_mpi_print (GCRYMPI_FMT_USG, NULL, 0,
&nbytes, pk->pkey[i]))
BUG ();
/* fixme: Better allocate BUF on the stack */
buf = xmalloc (nbytes);
if (gcry_mpi_print (GCRYMPI_FMT_USG, buf, nbytes,
NULL, pk->pkey[i]))
BUG ();
gcry_md_write (md, buf, nbytes);
xfree (buf);
}
}
gcry_md_final (md);
if (!array)
array = xmalloc (16);
len = 16;
memcpy (array, gcry_md_read (md, DIGEST_ALGO_MD5), 16);
gcry_md_close(md);
}
else
{
if (!array)
array = xmalloc(16);
len = 16;
memset (array,0,16);
}
}
else
{
gcry_md_hd_t md;
md = do_fingerprint_md(pk);
dp = gcry_md_read( md, 0 );
len = gcry_md_get_algo_dlen (gcry_md_get_algo (md));
assert( len <= MAX_FINGERPRINT_LEN );
if (!array)
array = xmalloc ( len );
memcpy (array, dp, len );
pk->keyid[0] = buf32_to_u32 (dp+12);
pk->keyid[1] = buf32_to_u32 (dp+16);
gcry_md_close( md);
}
*ret_len = len;
return array;
}
byte *
fingerprint_from_sk( PKT_secret_key *sk, byte *array, size_t *ret_len )
{
byte *buf;
const char *dp;
size_t len, nbytes;
int i;
if (sk->version < 4)
{
if ( is_RSA(sk->pubkey_algo) )
{
/* RSA in version 3 packets is special. */
gcry_md_hd_t md;
if (gcry_md_open (&md, DIGEST_ALGO_MD5, 0))
BUG ();
if (pubkey_get_npkey( sk->pubkey_algo ) > 1)
{
for (i=0; i < 2; i++)
{
if (gcry_mpi_print (GCRYMPI_FMT_USG, NULL, 0,
&nbytes, sk->skey[i]))
BUG ();
/* fixme: Better allocate BUF on the stack */
buf = xmalloc (nbytes);
if (gcry_mpi_print (GCRYMPI_FMT_USG, buf, nbytes,
NULL, sk->skey[i]))
BUG ();
gcry_md_write (md, buf, nbytes);
xfree (buf);
}
}
gcry_md_final(md);
if (!array)
array = xmalloc (16);
len = 16;
memcpy (array, gcry_md_read (md, DIGEST_ALGO_MD5), 16);
gcry_md_close (md);
}
else
{
if (!array)
array = xmalloc (16);
len=16;
memset (array,0,16);
}
}
else
{
gcry_md_hd_t md;
md = do_fingerprint_md_sk(sk);
if (md)
{
dp = gcry_md_read ( md, 0 );
len = gcry_md_get_algo_dlen ( gcry_md_get_algo (md) );
assert ( len <= MAX_FINGERPRINT_LEN );
if (!array)
array = xmalloc( len );
memcpy (array, dp, len);
gcry_md_close (md);
}
else
{
len = MAX_FINGERPRINT_LEN;
if (!array)
array = xmalloc (len);
memset (array, 0, len);
}
}
*ret_len = len;
return array;
}
/* Create a serialno/fpr string from the serial number and the secret
key. Caller must free the returned string. There is no error
return. */
char *
serialno_and_fpr_from_sk (const unsigned char *sn, size_t snlen,
PKT_secret_key *sk)
{
unsigned char fpr[MAX_FINGERPRINT_LEN];
size_t fprlen;
char *buffer, *p;
int i;
fingerprint_from_sk (sk, fpr, &fprlen);
buffer = p = xmalloc (snlen*2 + 1 + fprlen*2 + 1);
for (i=0; i < snlen; i++, p+=2)
sprintf (p, "%02X", sn[i]);
*p++ = '/';
for (i=0; i < fprlen; i++, p+=2)
sprintf (p, "%02X", fpr[i]);
*p = 0;
return buffer;
}