gnupg/g10/keygen.c

357 lines
9.1 KiB
C

/* keygen.c - generate a key pair
* Copyright (c) 1997 by Werner Koch (dd9jn)
*
* This file is part of G10.
*
* G10 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.
*
* G10 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 <assert.h>
#include "util.h"
#include "main.h"
#include "packet.h"
#include "cipher.h"
#include "ttyio.h"
#include "options.h"
#if 0
#define TEST_ALGO 1
#define TEST_NBITS 256
#define TEST_UID "Karl Test"
#endif
static int
answer_is_yes( const char *s )
{
if( !stricmp(s, "yes") )
return 1;
if( *s == 'y' && !s[1] )
return 1;
if( *s == 'Y' && !s[1] )
return 1;
return 0;
}
static void
write_uid( IOBUF out, const char *s )
{
PACKET pkt;
size_t n = strlen(s);
int rc;
pkt.pkttype = PKT_USER_ID;
pkt.pkt.user_id = m_alloc( sizeof *pkt.pkt.user_id + n - 1 );
pkt.pkt.user_id->len = n;
strcpy(pkt.pkt.user_id->name, s);
if( (rc = build_packet( out, &pkt )) )
log_error("build_packet(user_id) failed: %s\n", g10_errstr(rc) );
free_packet( &pkt );
}
#ifdef HAVE_RSA_CIPHER
static int
gen_rsa(unsigned nbits, IOBUF pub_io, IOBUF sec_io)
{
int rc;
PACKET pkt1, pkt2;
PKT_secret_cert *skc;
PKT_public_cert *pkc;
RSA_public_key pk;
RSA_secret_key sk;
rsa_generate( &pk, &sk, nbits );
skc = m_alloc( sizeof *skc );
pkc = m_alloc( sizeof *pkc );
skc->timestamp = pkc->timestamp = make_timestamp();
skc->valid_days = pkc->valid_days = 0; /* fixme: make it configurable*/
skc->pubkey_algo = pkc->pubkey_algo = PUBKEY_ALGO_RSA;
memset(&pkc->mfx, 0, sizeof pkc->mfx);
pkc->d.rsa.rsa_n = pk.n;
pkc->d.rsa.rsa_e = pk.e;
skc->d.rsa.rsa_n = sk.n;
skc->d.rsa.rsa_e = sk.e;
skc->d.rsa.rsa_d = sk.d;
skc->d.rsa.rsa_p = sk.p;
skc->d.rsa.rsa_q = sk.q;
skc->d.rsa.rsa_u = sk.u;
skc->d.rsa.calc_csum = 0;
skc->d.rsa.is_protected = 0; /* FIXME!!! */
skc->d.rsa.protect_algo = 0; /* should be blowfish */
/*memcpy(skc->d.rsa.protect.blowfish.iv,"12345678", 8);*/
init_packet(&pkt1);
pkt1.pkttype = PKT_PUBLIC_CERT;
pkt1.pkt.public_cert = pkc;
init_packet(&pkt2);
pkt2.pkttype = PKT_SECRET_CERT;
pkt2.pkt.secret_cert = skc;
if( (rc = build_packet( pub_io, &pkt1 )) ) {
log_error("build public_cert packet failed: %s\n", g10_errstr(rc) );
goto leave;
}
if( (rc = build_packet( sec_io, &pkt2 )) ) {
log_error("build secret_cert packet failed: %s\n", g10_errstr(rc) );
goto leave;
}
leave:
free_packet(&pkt1);
free_packet(&pkt2);
return rc;
}
#endif /*HAVE_RSA_CIPHER*/
static int
gen_elg(unsigned nbits, IOBUF pub_io, IOBUF sec_io)
{
int rc;
PACKET pkt1, pkt2;
PKT_secret_cert *skc;
PKT_public_cert *pkc;
ELG_public_key pk;
ELG_secret_key sk;
elg_generate( &pk, &sk, nbits );
skc = m_alloc( sizeof *skc );
pkc = m_alloc( sizeof *pkc );
skc->timestamp = pkc->timestamp = make_timestamp();
skc->valid_days = pkc->valid_days = 0; /* fixme: make it configurable*/
skc->pubkey_algo = pkc->pubkey_algo = PUBKEY_ALGO_ELGAMAL;
memset(&pkc->mfx, 0, sizeof pkc->mfx);
pkc->d.elg.p = pk.p;
pkc->d.elg.g = pk.g;
pkc->d.elg.y = pk.y;
skc->d.elg.p = sk.p;
skc->d.elg.g = sk.g;
skc->d.elg.y = sk.y;
skc->d.elg.x = sk.x;
skc->d.elg.calc_csum = 0;
skc->d.elg.is_protected = 0; /* FIXME!!! */
skc->d.elg.protect_algo = 0; /* should be blowfish */
/*memcpy(skc->d.elg.protect.blowfish.iv,"12345678", 8);*/
init_packet(&pkt1);
pkt1.pkttype = PKT_PUBLIC_CERT;
pkt1.pkt.public_cert = pkc;
init_packet(&pkt2);
pkt2.pkttype = PKT_SECRET_CERT;
pkt2.pkt.secret_cert = skc;
if( (rc = build_packet( pub_io, &pkt1 )) ) {
log_error("build public_cert packet failed: %s\n", g10_errstr(rc) );
goto leave;
}
if( (rc = build_packet( sec_io, &pkt2 )) ) {
log_error("build secret_cert packet failed: %s\n", g10_errstr(rc) );
goto leave;
}
leave:
free_packet(&pkt1);
free_packet(&pkt2);
return rc;
}
/****************
* Generate a keypair
*/
void
generate_keypair()
{
char *answer;
unsigned nbits;
char *pub_fname = "./pubring.g10";
char *sec_fname = "./secring.g10";
char *uid = NULL;
IOBUF pub_io = NULL;
IOBUF sec_io = NULL;
int rc;
int algo;
const char *algo_name;
#ifndef TEST_ALGO
if( opt.batch || opt.answer_yes || opt.answer_no )
log_fatal("Key generation can only be used in interactive mode\n");
tty_printf("Please select the algorithm to use:\n"
" (1) ElGamal is the suggested one.\n"
#ifdef HAVE_RSA_CIPHER
" (2) RSA cannot be used inthe U.S.\n"
#endif
);
#endif
for(;;) {
#ifdef TEST_ALGO
algo = TEST_ALGO;
#else
answer = tty_get("Your selection? (1,2) ");
tty_kill_prompt();
algo = *answer? atoi(answer): 1;
m_free(answer);
#endif
if( algo == 1 ) {
algo = PUBKEY_ALGO_ELGAMAL;
algo_name = "ElGamal";
break;
}
#ifdef HAVE_RSA_CIPHER
else if( algo == 2 ) {
algo = PUBKEY_ALGO_RSA;
algo_name = "RSA";
break;
}
#endif
}
tty_printf("About to generate a new %s keypair.\n"
#ifndef TEST_NBITS
" minimum keysize is 768 bits\n"
" default keysize is 1024 bits\n"
" highest suggested keysize is 2048 bits\n"
#endif
, algo_name );
for(;;) {
#ifdef TEST_NBITS
nbits = TEST_NBITS;
#else
answer = tty_get("What keysize do you want? (1024) ");
tty_kill_prompt();
nbits = *answer? atoi(answer): 1024;
m_free(answer);
#endif
if( nbits < 128 ) /* FIXME: change this to 768 */
tty_printf("keysize too small; please select a larger one\n");
else if( nbits > 2048 ) {
tty_printf("Keysizes larger than 2048 are not suggested, because "
"computations take REALLY long!\n");
answer = tty_get("Are you sure, that you want this keysize? ");
tty_kill_prompt();
if( answer_is_yes(answer) ) {
m_free(answer);
tty_printf("Okay, but keep in mind that your monitor "
"and keyboard radiation is also very vulnerable "
"to attacks!\n");
break;
}
m_free(answer);
}
else
break;
}
tty_printf("Requested keysize is %u bits\n", nbits );
if( (nbits % 32) ) {
nbits = ((nbits + 31) / 32) * 32;
tty_printf("rounded up to %u bits\n", nbits );
}
#ifdef TEST_UID
uid = m_alloc(strlen(TEST_UID)+1);
strcpy(uid, TEST_UID);
#else
tty_printf( "\nYou need a User-ID to identify your key; please use your name and your\n"
"email address in this suggested format:\n"
" \"Heinrich Heine <heinrichh@uni-duesseldorf.de>\n" );
uid = NULL;
for(;;) {
m_free(uid);
tty_printf("\n");
uid = tty_get("Your User-ID: ");
tty_kill_prompt();
if( strlen(uid) < 5 )
tty_printf("Please enter a string of at least 5 characters\n");
else {
tty_printf("You selected this USER-ID:\n \"%s\"\n\n", uid);
answer = tty_get("Is this correct? ");
tty_kill_prompt();
if( answer_is_yes(answer) ) {
m_free(answer);
break;
}
m_free(answer);
}
}
#endif
/* now check wether we a are allowed to write the keyrings */
if( !(rc=overwrite_filep( pub_fname )) ) {
if( !(pub_io = iobuf_create( pub_fname )) )
log_error("can't create %s: %s\n", pub_fname, strerror(errno) );
else if( opt.verbose )
log_info("writing to '%s'\n", pub_fname );
}
else if( rc != -1 ) {
log_error("Oops: overwrite_filep(%s): %s\n", pub_fname, g10_errstr(rc) );
m_free(uid);
return;
}
else {
m_free(uid);
return;
}
if( !(rc=overwrite_filep( sec_fname )) ) {
if( !(sec_io = iobuf_create( sec_fname )) )
log_error("can't create %s: %s\n", sec_fname, strerror(errno) );
else if( opt.verbose )
log_info("writing to '%s'\n", sec_fname );
}
else if( rc != -1 ) {
log_error("Oops: overwrite_filep(%s): %s\n", sec_fname, g10_errstr(rc) );
m_free(uid);
return;
}
else {
iobuf_cancel(pub_io);
m_free(uid);
return;
}
write_comment( pub_io, "#public key created by G10 pre-release " VERSION );
write_comment( sec_io, "#secret key created by G10 pre-release " VERSION );
if( algo == PUBKEY_ALGO_ELGAMAL )
gen_elg(nbits, pub_io, sec_io);
#ifdef HAVE_RSA_CIPHER
else if( algo == PUBKEY_ALGO_RSA )
gen_rsa(nbits, pub_io, sec_io);
#endif
else
log_bug(NULL);
write_uid(pub_io, uid );
write_uid(sec_io, uid );
m_free(uid);
iobuf_close(pub_io);
iobuf_close(sec_io);
}