1
0
mirror of git://git.gnupg.org/gnupg.git synced 2024-11-09 21:28:51 +01:00
gnupg/g10/keyid.c
David Shaw 4830eb7cae * keyid.c (do_fingerprint_md): Properly handle hashing of keys that we
don't know the structure of by using the opaque MPI.
(do_fingerprint_md_sk): We cannot calculate the fingerprint from a secret
key unless we know the structure (since we can't leave off the secret key
parts), so fail early..... (keyid_from_sk, fingerprint_from_sk): .... and
return all zeroes.
2003-12-10 01:27:55 +00:00

546 lines
12 KiB
C

/* keyid.c - key ID and fingerprint handling
* Copyright (C) 1998, 1999, 2000, 2001, 2003 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 <errno.h>
#include <time.h>
#include <assert.h>
#include "util.h"
#include "main.h"
#include "packet.h"
#include "options.h"
#include "mpi.h"
#include "keydb.h"
#include "i18n.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' ;
default: return '?';
}
}
static MD_HANDLE
do_fingerprint_md( PKT_public_key *pk )
{
MD_HANDLE md;
unsigned n;
unsigned nb[PUBKEY_MAX_NPKEY];
unsigned nn[PUBKEY_MAX_NPKEY];
byte *pp[PUBKEY_MAX_NPKEY];
int i;
int npkey = pubkey_get_npkey( pk->pubkey_algo );
md = md_open( pk->version < 4 ? DIGEST_ALGO_RMD160 : DIGEST_ALGO_SHA1, 0);
n = pk->version < 4 ? 8 : 6;
if(npkey==0 && pk->pkey[0] && mpi_is_opaque(pk->pkey[0]))
{
pp[0]=mpi_get_opaque(pk->pkey[0],&nn[0]);
n+=nn[0];
}
else
for(i=0; i < npkey; i++ )
{
nb[i] = mpi_get_nbits(pk->pkey[i]);
pp[i] = mpi_get_buffer( pk->pkey[i], nn+i, NULL );
n += 2 + nn[i];
}
md_putc( md, 0x99 ); /* ctb */
md_putc( md, n >> 8 ); /* 2 byte length header */
md_putc( md, n );
if( pk->version < 4 )
md_putc( md, 3 );
else
md_putc( md, 4 );
{ u32 a = pk->timestamp;
md_putc( md, a >> 24 );
md_putc( md, a >> 16 );
md_putc( md, a >> 8 );
md_putc( md, a );
}
if( pk->version < 4 ) {
u16 a;
if( pk->expiredate )
a = (u16)((pk->expiredate - pk->timestamp) / 86400L);
else
a = 0;
md_putc( md, a >> 8 );
md_putc( md, a );
}
md_putc( md, pk->pubkey_algo );
if(npkey==0 && pk->pkey[0] && mpi_is_opaque(pk->pkey[0]))
md_write(md,pp[0],nn[0]);
else
for(i=0; i < npkey; i++ )
{
md_putc( md, nb[i]>>8);
md_putc( md, nb[i] );
md_write( md, pp[i], nn[i] );
m_free(pp[i]);
}
md_final( md );
return md;
}
static MD_HANDLE
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 );
}
/****************
* 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->version < 4 && is_RSA(sk->pubkey_algo) ) {
lowbits = pubkey_get_npkey(sk->pubkey_algo) ?
mpi_get_keyid( sk->skey[0], keyid ) : 0; /* take n */
}
else {
const byte *dp;
MD_HANDLE md;
md = do_fingerprint_md_sk(sk);
if(md)
{
dp = md_read( md, 0 );
keyid[0] = dp[12] << 24 | dp[13] << 16 | dp[14] << 8 | dp[15] ;
keyid[1] = dp[16] << 24 | dp[17] << 16 | dp[18] << 8 | dp[19] ;
lowbits = keyid[1];
md_close(md);
}
else
keyid[0]=keyid[1]=0;
}
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 && is_RSA(pk->pubkey_algo) ) {
lowbits = pubkey_get_npkey(pk->pubkey_algo) ?
mpi_get_keyid( pk->pkey[0], keyid ) : 0 ; /* from n */
pk->keyid[0] = keyid[0];
pk->keyid[1] = keyid[1];
}
else {
const byte *dp;
MD_HANDLE md;
md = do_fingerprint_md(pk);
dp = md_read( md, 0 );
keyid[0] = dp[12] << 24 | dp[13] << 16 | dp[14] << 8 | dp[15] ;
keyid[1] = dp[16] << 24 | dp[17] << 16 | dp[18] << 8 | dp[19] ;
lowbits = keyid[1];
md_close(md);
pk->keyid[0] = keyid[0];
pk->keyid[1] = keyid[1];
}
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] = dp[12] << 24 | dp[13] << 16 | dp[14] << 8 | dp[15] ;
keyid[1] = dp[16] << 24 | dp[17] << 16 | dp[18] << 8 | dp[19] ;
}
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==NULL)
{
uid->namehash=m_alloc(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 *
colon_strtime (u32 t)
{
if (!t)
return "";
if (opt.fixed_list_mode) {
static char buf[15];
sprintf (buf, "%lu", (ulong)t);
return buf;
}
return strtimestamp(t);
}
const char *
colon_datestr_from_pk (PKT_public_key *pk)
{
if (opt.fixed_list_mode) {
static char buf[15];
sprintf (buf, "%lu", (ulong)pk->timestamp);
return buf;
}
return datestr_from_pk (pk);
}
const char *
colon_datestr_from_sk (PKT_secret_key *sk)
{
if (opt.fixed_list_mode) {
static char buf[15];
sprintf (buf, "%lu", (ulong)sk->timestamp);
return buf;
}
return datestr_from_sk (sk);
}
const char *
colon_datestr_from_sig (PKT_signature *sig)
{
if (opt.fixed_list_mode) {
static char buf[15];
sprintf (buf, "%lu", (ulong)sig->timestamp);
return buf;
}
return datestr_from_sig (sig);
}
const char *
colon_expirestr_from_sig (PKT_signature *sig)
{
if(!sig->expiredate)
return "";
if (opt.fixed_list_mode) {
static char buf[15];
sprintf (buf, "%lu", (ulong)sig->expiredate);
return buf;
}
return expirestr_from_sig (sig);
}
/**************** .
* 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 *p, *buf;
const byte *dp;
size_t len;
unsigned int n;
if( pk->version < 4 && is_RSA(pk->pubkey_algo) ) {
/* RSA in version 3 packets is special */
MD_HANDLE md;
md = md_open( DIGEST_ALGO_MD5, 0);
if( pubkey_get_npkey( pk->pubkey_algo ) > 1 ) {
p = buf = mpi_get_buffer( pk->pkey[0], &n, NULL );
md_write( md, p, n );
m_free(buf);
p = buf = mpi_get_buffer( pk->pkey[1], &n, NULL );
md_write( md, p, n );
m_free(buf);
}
md_final(md);
if( !array )
array = m_alloc( 16 );
len = 16;
memcpy(array, md_read(md, DIGEST_ALGO_MD5), 16 );
md_close(md);
}
else {
MD_HANDLE md;
md = do_fingerprint_md(pk);
dp = md_read( md, 0 );
len = md_digest_length( md_get_algo( md ) );
assert( len <= MAX_FINGERPRINT_LEN );
if( !array )
array = m_alloc( len );
memcpy(array, dp, len );
pk->keyid[0] = dp[12] << 24 | dp[13] << 16 | dp[14] << 8 | dp[15] ;
pk->keyid[1] = dp[16] << 24 | dp[17] << 16 | dp[18] << 8 | dp[19] ;
md_close(md);
}
*ret_len = len;
return array;
}
byte *
fingerprint_from_sk( PKT_secret_key *sk, byte *array, size_t *ret_len )
{
byte *p, *buf;
const char *dp;
size_t len;
unsigned n;
if( sk->version < 4 && is_RSA(sk->pubkey_algo) ) {
/* RSA in version 3 packets is special */
MD_HANDLE md;
md = md_open( DIGEST_ALGO_MD5, 0);
if( pubkey_get_npkey( sk->pubkey_algo ) > 1 ) {
p = buf = mpi_get_buffer( sk->skey[0], &n, NULL );
md_write( md, p, n );
m_free(buf);
p = buf = mpi_get_buffer( sk->skey[1], &n, NULL );
md_write( md, p, n );
m_free(buf);
}
md_final(md);
if( !array )
array = m_alloc( 16 );
len = 16;
memcpy(array, md_read(md, DIGEST_ALGO_MD5), 16 );
md_close(md);
}
else {
MD_HANDLE md;
md = do_fingerprint_md_sk(sk);
if(md)
{
dp = md_read( md, 0 );
len = md_digest_length( md_get_algo( md ) );
assert( len <= MAX_FINGERPRINT_LEN );
if( !array )
array = m_alloc( len );
memcpy(array, dp, len );
md_close(md);
}
else
{
len=MAX_FINGERPRINT_LEN;
if(!array)
array=m_alloc(len);
memset(array,0,len);
}
}
*ret_len = len;
return array;
}